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Sample records for hydroponic solution bioavailability

  1. Reuse of hydroponic waste solution.

    PubMed

    Kumar, Ramasamy Rajesh; Cho, Jae Young

    2014-01-01

    Attaining sustainable agriculture is a key goal in many parts of the world. The increased environmental awareness and the ongoing attempts to execute agricultural practices that are economically feasible and environmentally safe promote the use of hydroponic cultivation. Hydroponics is a technology for growing plants in nutrient solutions with or without the use of artificial medium to provide mechanical support. Major problems for hydroponic cultivation are higher operational cost and the causing of pollution due to discharge of waste nutrient solution. The nutrient effluent released into the environment can have negative impacts on the surrounding ecosystems as well as the potential to contaminate the groundwater utilized by humans for drinking purposes. The reuse of non-recycled, nutrient-rich hydroponic waste solution for growing plants in greenhouses is the possible way to control environmental pollution. Many researchers have successfully grown several plant species in hydroponic waste solution with high yield. Hence, this review addresses the problems associated with the release of hydroponic waste solution into the environment and possible reuse of hydroponic waste solution as an alternative resource for agriculture development and to control environmental pollution. PMID:24838258

  2. Solution Culture Hydroponics: History and Inexpensive Equipment.

    ERIC Educational Resources Information Center

    Hershey, David R.

    1994-01-01

    Describes historical accounts dating back to as early as 604-562 BC of the various uses of hydroponics. Throughout the article, diagrams and simple instructions are provided to aid in classroom use of hydroponics. (ZWH)

  3. Laboratory Evaluation of Ion-Selective Electrodes for Simultaneous Analysis of Macronutrients in Hydroponic Solution

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Automated sensing of macronutrients in hydroponic solution would allow more efficient management of nutrients for crop growth in closed hydroponic systems. Ion-selective microelectrode technology requires an ion-selective membrane or a solid metal material that responds selectively to one analyte in...

  4. Sterilisation of Hydroponic Culture Solution Contaminated by Fungi using an Atmospheric Pressure Corona Discharge

    NASA Astrophysics Data System (ADS)

    Mizukami, Kohji; Satoh, Kohki; Kanayama, Hiroshi; Itoh, Hidenori; Tagashira, Hiroaki; Shimozuma, Mitsuo; Okamoto, Hiroyuki; Takasaki, Satoko; Kinoshita, Muneshige

    The hydroponic culture solution contaminated by fungi is sterilised by a DC corona discharge, and the sterilisation characteristics are investigated in this work. A DC streamer corona discharge is generated at atmospheric pressure in air between needle clusters and a water bath containing contaminated solution by fungus such as Fusarium oxysporum f. sp. spinaciae or Fusarium sp.. It is found that the fungi are killed by the exposure of the corona discharge, and that the death rates of the fungi chiefly depend on the concentration of the hydroponic culture solutions. It is also found that the number densities of the fungi decrease exponentially with the energy expenditure of the corona discharge, and that damping coefficients of the fungi densities depend on the concentration of the hydroponic culture solutions. This suggests that the fungi are chiefly inactivated by electroporation.

  5. The effects of nutrient solution sterilization on the growth and yield of hydroponically grown lettuce

    NASA Technical Reports Server (NTRS)

    Schwartzkopf, S. H.; Dudzinski, D.; Minners, R. S.

    1987-01-01

    Two methods of removing bacteria from hydroponic nutrient solution [ultraviolet (UV) radiation and submicronic filter] were evaluated for efficiency and for their effects on lettuce (Lactuca sativa L.) production. Both methods were effective in removing bacteria; but, at high intensity, the ultraviolet sterilizer significantly inhibited the production of plants grown in the treated solution. Bacterial removal by lower intensity UV or a submicronic filter seemed to promote plant growth slightly, but showed no consistent, statistically significant effect.

  6. Development of a vinasse nutritive solution for hydroponics.

    PubMed

    dos Santos, José Darcy; Lopes da Silva, André Luís; da Luz Costa, Jefferson; Scheidt, Gessiel Newton; Novak, Alessandra Cristine; Sydney, Eduardo Bittencourt; Soccol, Carlos Ricardo

    2013-01-15

    Vinasse is a residue that originates from the distillation of fuel alcohol. However, it contains a relative amount of nutrients. The aim of this work was to develop a nutritive solution using vinasse and to compare it with a commercial solution for the cultivation of lettuce, watercress and rocket. Vinasse obtained from juice must was decanted and filtered, followed by chemical analyses of the nutrients. A nutritive solution composed of 10% vinasse supplemented with nutrients was in agreement with the results of the chemical analyses (a similar amount of Furlani's solution). Experiments were then performed in an NFT (Nutrient film technique) system. The treatments used the vinasse solution and a commercial solution constituted from a Yara Fertilizantes(®) product. The height of the aerial part and the number of leaves of the crops were evaluated at 7, 14, 21, 28, 35 and 42 days. In most crops, the results were very similar. The vinasse solution promoted a larger number of leaves in lettuce and the highest aerial part in watercress. For the rocket, there were no significant differences between the two solutions. In conclusion, a nutritive solution was developed using vinasse, and this solution provided suitable growth, which was higher in some cases, for the crops studied herein. This study shows the great potential of this technology as a rational alternative to vinasse disposal. PMID:23201600

  7. Treatment of drainage solution from hydroponic greenhouse production with microalgae.

    PubMed

    Hultberg, Malin; Carlsson, Anders S; Gustafsson, Susanne

    2013-05-01

    This study investigated treatment of the drainage solution from greenhouse production with microalgae, through inoculation with Chlorella vulgaris or through growth of the indigenous microalgal community. A significant reduction in nitrogen, between 34.7 and 73.7 mg L(-1), and particularly in phosphorus concentration, between 15.4 and 15.9 mg L(-1), was observed in drainage solution collected from commercial greenhouse production. The large reduction in nutrients was achieved through growth of the indigenous microalgal community i.e., without pre-treatment of the drainage solution or inoculation with the fast growing green microalgae C. vulgaris. Analysis of the fatty acid composition of the algal biomass revealed that compared with a standard growth medium for green algae, the drainage solution was inferior for lipid production. Despite the biorefinery concept being less promising, microalgae-based treatment of drainage solution from greenhouse production is still of interest considering the urgent need for phosphorus recycling. PMID:23567708

  8. Excess nutrients in hydroponic solutions alter nutrient content of rice, wheat, and potato

    NASA Technical Reports Server (NTRS)

    McKeehen, J. D.; Mitchell, C. A.; Wheeler, R. M.; Bugbee, B.; Nielsen, S. S.

    1996-01-01

    Environment has significant effects on the nutrient content of field-grown crop plants. Little is known, however, about compositional changes caused by controlled environments in which plants receive only artificial radiation and soilless, hydroponic culture. This knowledge is essential for developing a safe, nutritious diet in a Controlled Ecological Life-Support System (CELSS). Three crops that are candidates for inclusion in a CELSS (rice, wheat, and white potato) were grown both in the field and in controlled environments where the hydroponic nutrient solution, photosynthetic photon flux (PPF), and CO2 level were manipulated to achieve rapid growth rates. Plants were harvested at maturity, separated into discrete parts, and dried prior to analysis. Plant materials were analyzed for proximate composition (protein, fat, ash, and carbohydrate), total nitrogen (N), nitrate, minerals, and amino-acid composition. The effect of environment on nutrient content varied by crop and plant part. Total N and nonprotein N (NPN) contents of plant biomass generally increased under controlled-environment conditions compared to field conditions, especially for leafy plant parts and roots. Nitrate levels were increased in hydroponically-grown vegetative tissues, but nitrate was excluded from grains and tubers. Mineral content changes in plant tissue included increased phosphorus and decreased levels of certain micronutrient elements under controlled-environment conditions. These findings suggest that cultivar selection, genetic manipulation, and environmental control could be important to obtain highly nutritious biomass in a CELSS.

  9. Excess nutrients in hydroponic solutions alter nutrient content of rice, wheat, and potato

    NASA Astrophysics Data System (ADS)

    McKeehen, J. D.; Mitchell, C. A.; Wheeler, R. M.; Bugbee, B.; Nielsen, S. S.

    Environment has significant effects on the nutrient content of field-grown crop plants. Little is known, however, about compositional changes caused by controlled environments in which plants receive only artificial radiation and soilless, hydroponic culture. This knowledge is essential for developing a safe, nutritious diet in a Controlled Ecological Life-Support System (CELSS). Three crops that are candidates for inclusion in a CELSS (rice, wheat, and white potato) were grown both in the field and in controlled environments where the hydroponic nutrient solution, photosynthetic photon flux (PPF), and CO_2 level were manipulated to achieve rapid growth rates. Plants were harvested at maturity, separated into discrete parts, and dried prior to analysis. Plant materials were analyzed for proximate composition (protein, fat, ash, and carbohydrate), total nitrogen (N), nitrate, minerals, and amino-acid composition. The effect of environment on nutrient content varied by crop and plant part. Total N and nonprotein N (NPN) contents of plant biomass generally increased under controlled-environment conditions compared to field conditions, especially for leafy plant parts and roots. Nitrate levels were increased in hydroponically-grown vegetative tissues, but nitrate was excluded from grains and tubers. Mineral content changes in plant tissue included increased phosphorus and decreased levels of certain micronutrient elements under controlled-environment conditions. These findings suggest that cultivar selection, genetic manipulation, and environmental control could be important to obtain highly nutritious biomass in a CELSS.

  10. Automated pH Control of Nutrient Solution in a Hydroponic Plant Growth System

    NASA Technical Reports Server (NTRS)

    Smith, B.; Dogan, N.; Aglan, H.; Mortley, D.; Loretan, P.

    1998-01-01

    Over, the years, NASA has played an important role in providing to and the development of automated nutrient delivery and monitoring, systems for growing crops hydroponically for long term space missions. One example are the systems used in the Biomass Production Chamber (BPC) at Kennedy Space Center (KSC). The current KSC monitoring system is based on an engineering workstation using standard analog/digital input/output hardware and custom written software. The monitoring system uses completely separate sensors to provide a check of control sensor accuracy and has the ability to graphically display and store data form past experiment so that they are available for data analysis [Fortson, 1992]. In many cases, growing systems have not been fitted with the kind of automated control systems as used at KSC. The Center for Food and Environmental Systems for Human Exploration of Space (CFESH) located on the campus of Tuskegee University, has effectively grown sweetpotatoes and peanuts hydroponically for the past five years. However they have adjusted the pH electrical conductivity and volume of the hydroponic nutrient solution only manually at times when the solution was to be replenished or changed out according to its protocol (e.g. one-week, two-week, or two-day cycle). But the pH of the nutrient solution flowing through the channel is neither known nor controlled between the update, change out, or replenishment period. Thus, the pH of the nutrient solution is not held at an optimum level over the span of the plant's growth cycle. To solve this dilemma, an automated system for the control and data logging of pH data relative to sweetpotato production using the nutrient film technique (NFT) has been developed, This paper discusses a microprocessor-based system, which was designed to monitor, control, and record the pH of a nutrient solution used for growing sweetpotatoes using NFT.

  11. Hydroponic Culture

    ERIC Educational Resources Information Center

    Steucek, G. L.; Yurkiewicz, W. J.

    1973-01-01

    Describes a hydroponic culture technique suitable for student exercises in biology. This technique of growing plants in nutrient solutions enhances plant growth, and is an excellent way to obtain intact plants with root systems free of soil or other particulate matter. (JR)

  12. Evidence of association of salmonellae with tomato plants grown hydroponically in inoculated nutrient solution.

    PubMed

    Guo, Xuan; van Iersel, Marc W; Chen, Jinru; Brackett, Robert E; Beuchat, Larry R

    2002-07-01

    The possibility of uptake of salmonellae by roots of hydroponically grown tomato plants was investigated. Within 1 day of exposure of plant roots to Hoagland nutrient solution containing 4.46 to 4.65 log(10) CFU of salmonellae/ml, the sizes of the pathogen populations were 3.01 CFU/g of hypocotyls and cotyledons and 3.40 log(10) CFU/g of stems for plants with intact root systems (control) and 2.55 log(10) CFU/g of hypocotyls and cotyledons for plants from which portions of the roots had been removed. A population of > or =3.38 log(10) CFU/g of hypocotyls-cotyledons, stems, and leaves of plants grown for 9 days was detected regardless of the root condition. Additional studies need to be done to unequivocally demonstrate that salmonellae can exist as endophytes in tomato plants grown under conditions that simulate commonly used agronomic practices. PMID:12089054

  13. Study of paracetamol 1-g oral solution bioavailability.

    PubMed

    Farre, M; Roset, P N; Abanades, S; Menoyo, E; Alvarez, Y; Rovira, M; Baena, A

    2008-01-01

    The aim of this work was to assess paracetamol bioavailability after administering 1 g in oral solution. Eighteen healthy volunteers were selected for this open-label study. A total of 15.4 ml of Gelocatil Oral Solution (Laboratorios Gelos, S.L.), corresponding to 1 g of paracetamol, were administered to fasting subjects. Blood samples were collected at 0 min, 10 min, 20 min, 30 min, 45 min, 1 h, 1.5 h, 2 h, 3 h, 4 h, 6 h, 8 h, 10 h and 12 h. Paracetamol plasma concentrations were determined by reverse-phase high-performance liquid chromatography. The study was conducted without deviations from protocol. Pharmacokinetic data from 18 subjects were allowed for estimating fast and high-paracetamol bioavailability: t(max) 20 min (10-45) [median (range)], C(max) 24. 3 mg/l (6.5) [mean (standard deviation)], AUC(0-t) 64.0 mg h/l (16.1) and AUC(0-00) 68.1 mg h/l (17.9). These results are comparable to those described for Gelocatil Oral Solution given at a 650 mg dose and for immediate release Gelocatil 650 mg tablets. Absorption speed was very fast, similar to that described for other oral-solution formulations, which provides an immediate onset of pain and fever relief. The results of this study show suitable bioavailability for 1 g Gelocatil Oral Solution, with fast-absorption speed that provides an immediate onset of pain and fever relief. PMID:18389096

  14. Uptake and translocation of p,p'-dichlorodiphenyldichloroethylene supplied in hydroponics solution to Cucurbita.

    PubMed

    Gent, Martin P N; White, Jason C; Parrish, Zakia D; Isleyen, Mehmet; Eitzer, Brian D; Mattina, MaryJane Incorvia

    2007-12-01

    Field studies show shoots of zucchini (Cucurbita pepo L.) accumulate various hydrophobic contaminants from soil, although many other plants do not, including cucumber (Cucumis sativus L.). To investigate the mechanism for this uptake, we presented p,p'-dichlorodiphenyldichloroethylene (DDE) to these two species in hydroponics solution. A mixture of DDE bound to Tenax beads stirred with a solution of water passing through a reservoir provided a flowing solution containing DDE at approximately 2 microg/L for many weeks duration. Approximately 90% of the DDE supplied in solution was adsorbed on the roots of both cucumber and zucchini. Less than 10% of the sorbed DDE was released subsequently when clean solution flowed past these contaminated roots for 9 d. The shoots of both species accumulated DDE, but the fraction that moved from the roots to the shoot in zucchini, ranging from 6 to 27% in various trials, was 10-fold greater than that in cucumber, 0.7 to 2%. The gradient in DDE concentration in zucchini tissues was in the order root more more than stem > petiole > leaf blade, indicating the movement was through the xylem in the transpiration stream. Some DDE in leaf blades might have been absorbed from the air, because the concentration in this tissue varied less with time, position in trough, or species, than did DDE in stems and petioles. The remarkable ability of zucchini to translocate DDE could not be attributed to differences in tissue composition, growth rate, distribution of weight among plant parts, or in the leaf area and rate of transpiration of water from leaves. Some other factor enables efficient translocation of hydrophobic organic contaminants in the xylem of zucchini. PMID:18020671

  15. Closed-Cycle Nutrient Supply For Hydroponics

    NASA Technical Reports Server (NTRS)

    Schwartzkopf, Steven H.

    1991-01-01

    Hydroponic system controls composition and feed rate of nutrient solution and recovers and recycles excess solution. Uses air pressure on bladders to transfer aqueous nutrient solution. Measures and adjusts composition of solution before it goes to hydroponic chamber. Eventually returns excess solution to one of tanks. Designed to operate in microgravity, also adaptable to hydroponic plant-growing systems on Earth.

  16. Measuring calcium, potassium, and nitrate in plant nutrient solutions using ion-selective electrodes in hydroponic greenhouse of some vegetables.

    PubMed

    Vardar, Gökay; Altıkatoğlu, Melda; Ortaç, Deniz; Cemek, Mustafa; Işıldak, İbrahim

    2015-01-01

    Generally, the life cycle of plants depends on the uptake of essential nutrients in a balanced manner and on toxic elements being under a certain concentration. Lack of control of nutrient levels in nutrient solution can result in reduced plant growth and undesired conditions such as blossom-end rot. In this study, sensitivity and selectivity tests for various polyvinylchloride (PVC)-based ion-selective membranes were conducted to identify those suitable for measuring typical concentration ranges of macronutrients, that is, NO(3-), K(+), and Ca(2+), in hydroponic solutions. The sensitivity and selectivity of PVC-membrane-based ion-selective sensors prepared with tetradodecylammoniumnitrate for NO(3-), valinomycin for K(+), and Ca ionophore IV for Ca(2+) were found to be satisfactory for measuring NO(3-), K(+), and Ca(2+) ions in nutrient solutions over typical ranges of hydroponic concentrations. Potassium, calcium, and nitrate levels that were utilized by cucumber and tomato seedlings in the greenhouse were different. The findings show that tomato plants consumed less amounts of nitrate than cucumber plants over the first 2 months of their growth. We also found that the potassium intake was higher than other nutritional elements tested for all plants. PMID:25388287

  17. Spectral Quantitation Of Hydroponic Nutrients

    NASA Technical Reports Server (NTRS)

    Schlager, Kenneth J.; Kahle, Scott J.; Wilson, Monica A.; Boehlen, Michelle

    1996-01-01

    Instrument continuously monitors hydroponic solution by use of absorption and emission spectrometry to determine concentrations of principal nutrients, including nitrate, iron, potassium, calcium, magnesium, phosphorus, sodium, and others. Does not depend on extraction and processing of samples, use of such surrograte parameters as pH or electrical conductivity for control, or addition of analytical reagents to solution. Solution not chemically altered by analysis and can be returned to hydroponic process stream after analysis.

  18. Hydroponic Gardening

    ERIC Educational Resources Information Center

    Julinor, Helmut

    1976-01-01

    In addition to being an actual source of foodstuffs in inhospitable climates and a potential source of a large portion of the world's food supply, hydroponic gardening is a useful technique in the classroom for illustrating the role of plant life in the world's food chain. (MB)

  19. Electrochemical control of pH in a hydroponic nutrient solution

    NASA Technical Reports Server (NTRS)

    Schwartzkopf, S. H.

    1986-01-01

    The electrochemical pH control system described was found to provide a feasible alternative method of controlling nutrient solution pH for CELSS applications. The plants grown in nutrient solution in which the pH was controlled electrochemically showed no adverse effects. Further research into the design of a larger capacity electrode bridge for better control is indicated by the results of this experiment, and is currently under way.

  20. Phytoextraction of cadmium by Ipomoea aquatica (water spinach) in hydroponic solution: effects of cadmium speciation.

    PubMed

    Wang, Kai-Sung; Huang, Lung-Chiu; Lee, Hong-Shen; Chen, Pai-Ye; Chang, Shih-Hsien

    2008-06-01

    Phytoextraction is a promising technique to remediate heavy metals from contaminated wastewater. However, the interactions of multi-contaminants are not fully clear. This study employed cadmium, Triton X-100 (TX-100), and EDTA to investigate their interactions on phytotoxicity and Cd phytoextraction of Ipomoea aquatica (water spinach) in simulated wastewater. The Cd speciation was estimated by a chemical equilibrium model and MINEQL+. Statistic regression was applied to evaluate Cd speciation on Cd uptake in shoots and stems of I. aquatica. Results indicated that the root length was a more sensitive parameter than root weight and shoot weight. Root elongation was affected by Cd in the Cd-EDTA solution and TX-100 in the Cd-TX-100 solution. Both the root length and the root biomass were negatively correlated with the total soluble Cd ions. In contrast, Cd phytoextraction of I. aquatic was correlated with the aqueous Cd ions in the free and complex forms rather than in the chelating form. Additionally, the high Cd bioconcentration factors of I. aquatica (375-2227 l kg(-1) for roots, 45-144 l kg(-1) for shoots) imply that I. aquatica is a potential aquatic plant to remediate Cd-contaminated wastewater. PMID:18471856

  1. Hydroponics in the Classroom.

    ERIC Educational Resources Information Center

    Sell, Merran

    1997-01-01

    Summarizes the benefits of using hydroponics in school for investigational work. Lists requirements and includes advice on suitable plant choices. Outlines the various growing systems and growing media and provides suggestions for science investigations using hydroponics. (DDR)

  2. Effect of different soil washing solutions on bioavailability of residual arsenic in soils and soil properties.

    PubMed

    Im, Jinwoo; Yang, Kyung; Jho, Eun Hea; Nam, Kyoungphile

    2015-11-01

    The effect of soil washing used for arsenic (As)-contaminated soil remediation on soil properties and bioavailability of residual As in soil is receiving increasing attention due to increasing interest in conserving soil qualities after remediation. This study investigates the effect of different washing solutions on bioavailability of residual As in soils and soil properties after soil washing. Regardless of washing solutions, the sequential extraction revealed that the residual As concentrations and the amount of readily labile As in soils were reduced after soil washing. However, the bioassay tests showed that the washed soils exhibited ecotoxicological effects - lower seed germination, shoot growth, and enzyme activities - and this could largely be attributed to the acidic pH and/or excessive nutrient contents of the washed soils depending on washing solutions. Overall, this study showed that treated soils having lower levels of contaminants could still exhibit toxic effects due to changes in soil properties, which highly depended on washing solutions. This study also emphasizes that data on the As concentrations, the soil properties, and the ecotoxicological effects are necessary to properly manage the washed soils for reuses. The results of this study can, thus, be utilized to select proper post-treatment techniques for the washed soils. PMID:26086811

  3. Labile synthetic cadmium complexes are not bioavailable to Pseudokirchneriella subcapitata in resin buffered solutions.

    PubMed

    Verheyen, L; Merckx, R; Smolders, E

    2012-11-15

    The Free Ion Activity Model (FIAM) predicts that cadmium (Cd) uptake by organisms is identical for solutions with the same free Cd(2+) concentration and inorganic composition. Clear exceptions to the FIAM have been shown for Cd uptake by plant roots, periphyton and human cells where labile Cd complexes increase bioavailability and which has been attributed to their role in enhancing Cd diffusion towards the uptake cells. Here, we assessed the role of labile Cd complexes on Cd uptake by algae, for which diffusion limitations should be less pronounced due to their smaller size. Long-term (3 days) Cd uptake by the green algae Pseudokirchneriella subcapitata was measured in resin buffered solutions with or without synthetic ligands and at three Cd(2+) ion activities (pCd 8.2-5.7). The free Cd(2+) activity was maintained during the test using a metal-selective resin located in the algal bottles. Total dissolved Cd increased up to 35-fold by adding the synthetic ligands at constant Cd(2+) activity. In contrast, Cd uptake by algae increased maximally 2.8 fold with increasing concentration of the synthetic ligands and the availability of the complexes were maximally 5.2% relative to Cd(2+) for NTA and CDTA complexes. It is concluded that labile Cd complexes do not greatly enhance Cd bioavailability to the unicellular algae and calculations suggest that Cd transport from solution to these small cells is not rate limiting. PMID:22903064

  4. Comparative bioavailability study of cefixime administered as tablets or aqueous solution.

    PubMed

    Montay, G; Masala, F; Le Roux, Y; Le Liboux, A; Uhlrich, J; Chassard, D; Thebault, J J; Roche, G; Frydman, A

    1991-01-01

    The relative bioavailability of cefixime was studied in 24 healthy male volunteers, with each subject receiving a single 400mg dose of cefixime administered as an aqueous solution, a 400mg tablet and two 200mg tablets, in a randomised crossover sequence. Serum and urine samples were analysed using high-performance liquid chromatography. Peak cefixime levels were achieved 3 hours after administration of the solution vs 4 hours for the 2 tablet formulations; however, the extent of absorption was only slightly improved with the solution (by 14 and 7% compared with the 1 x 400 and 2 x 200mg tablets, respectively). The 400mg and 2 x 200mg tablets were found to be bioequivalent. The pharmacokinetic profile of the 400mg cefixime tablet (mean maximum plasma concentrations of 4.4 mg/L at 4 hours, area under the concentration-time curve of 34.4 mg/L.h, and apparent terminal elimination half-life of 3.7 hours) supports the clinical evaluation of a 400mg once-daily dosage regimen for cefixime. PMID:1725153

  5. Efflux Of Nitrate From Hydroponically Grown Wheat

    NASA Technical Reports Server (NTRS)

    Huffaker, R. C.; Aslam, M.; Ward, M. R.

    1992-01-01

    Report describes experiments to measure influx, and efflux of nitrate from hydroponically grown wheat seedlings. Ratio between efflux and influx greater in darkness than in light; increased with concentration of nitrate in nutrient solution. On basis of experiments, authors suggest nutrient solution optimized at lowest possible concentration of nitrate.

  6. Hydroponics or soilless culture

    NASA Technical Reports Server (NTRS)

    Chapman, H. D.

    1963-01-01

    Historically, hydroponics is not a new field; plant physiologists have known and used it for some 100 years. Inevitably, some enthusiasts got carried away.Claims were made of enormous potential yields; skyscraper tops were said to be capable of producing enough food for all of their occupants; and closets, basements, garages, etc. were wishfully converted into fields for hydroponic culture. Numerous publications on the subject appeared during this period. Basic requirements for hydropinc techniques are given along with examples of where soilless culture has been used commercially.

  7. Rooting greenwood tip cuttings of several Populus clones hydroponically (hydroponic rooting of Populus cuttings)

    SciTech Connect

    Phipps, H.M.; Hansen, E.A.; Tolsted, D.N.

    1980-01-01

    Greenwood cuttings of several Populus clones were successfully rooted with a relatively simple hydroponic method. Indolebutyric acid and naphthaleneacetic acid at concentrations of 500 to 5000 ppM applied as a quick dip to the cutting bases, a complete nutrient solution at 20 to 40% of full strength, and a solution temperature between 27 and 30/sup 0/C generally produced the best rooting performance of most clones. Cuttings propagated by the hydroponic procedure rooted faster and generally outgrew those produced by a standard method after being transplanted to pots and grown in the greenhouse.

  8. Hands-On Hydroponics

    ERIC Educational Resources Information Center

    Carver, Jeffrey; Wasserman, Bradley

    2012-01-01

    Hydroponics is a process in which plants are grown using nutrient-rich water instead of soil. Because this process maximizes the use of water and nutrients--providing only what the plant uses in controlled and easily maintained systems--it is a viable alternative to traditional farming methods. The amount of control in these systems also ensures…

  9. Phytoaccumulation of antimicrobials by hydroponic Cucurbita pepo.

    PubMed

    Aryal, Niroj; Reinhold, Dawn

    2013-01-01

    Consumer use of antimicrobial-containing products continuously introduces triclocarban and triclosan into the environment. Triclocarban and triclosan adversely affect plants and animals and have the potential to affect human health. Research examined the phytoaccumulation of triclocarban and triclosan by pumpkin (Cucurbita pepo cultivar Howden) and zucchini (Cucurbita pepo cultivar Gold Rush) grown hydroponically. Pumpkin and zucchini were grown in nutrient solution spiked with 0.315 microg/mL triclocarban and 0.289 microg/mL triclosan for two months. Concentrations of triclocarban and triclosan in nutrient solutions were monitored weekly. At the end of the trial, roots and shoots were analyzed for triclocarban and triclosan. Research demonstrated that pumpkin and zucchini accumulated triclocarban and triclosan. Root accumulation factors were 1.78 and 0.64 and translocation factors were 0.001 and 0.082 for triclocarban and triclosan, respectively. The results of this experiment were compared with a previous soil column study that represented environmentally relevant exposure of antimicrobials from biosolids and had similar root mass. Plants were not as efficient in removing triclocarban and triclosan in hydroponic systems as in soil systems. Shoot concentrations of antimicrobials were the same or lower in hydroponic systems than in soil columns, indicating that hydroponic system does not overpredict the concentrations of antimicrobials. PMID:23487999

  10. Relative bioavailability of diclofenac potassium from softgel capsule versus powder for oral solution and immediate-release tablet formulation.

    PubMed

    Bende, Girish; Biswal, Shibadas; Bhad, Prafulla; Chen, Yuming; Salunke, Atish; Winter, Serge; Wagner, Robert; Sunkara, Gangadhar

    2016-01-01

    The oral bioavailability of diclofenac potassium 50 mg administered as a soft gelatin capsule (softgel capsule), powder for oral solution (oral solution), and tablet was evaluated in a randomized, open-label, 3-period, 6-sequence crossover study in healthy adults. Plasma diclofenac concentrations were measured using a validated liquid chromatography-mass spectrometry/mass spectrometry method, and pharmacokinetic analysis was performed by noncompartmental methods. The median time to achieve peak plasma concentrations of diclofenac was 0.5, 0.25, and 0.75 hours with the softgel capsule, oral solution, and tablet formulations, respectively. The geometric mean ratio and associated 90%CI for AUCinf, and Cmax of the softgel capsule formulation relative to the oral solution formulation were 0.97 (0.95-1.00) and 0.85 (0.76-0.95), respectively. The geometric mean ratio and associated 90%CI for AUCinf and Cmax of the softgel capsule formulation relative to the tablet formulation were 1.04 (1.00-1.08) and 1.67 (1.43-1.96), respectively. In conclusion, the exposure (AUC) of diclofenac with the new diclofenac potassium softgel capsule formulation was comparable to that of the existing oral solution and tablet formulations. The peak plasma concentration of diclofenac from the new softgel capsule was 67% higher than the existing tablet formulation, whereas it was 15% lower in comparison with the oral solution formulation. PMID:27119581

  11. Oral bioavailability in sheep of albendazole from a suspension and from a solution containing hydroxypropyl-beta-cyclodextrin.

    PubMed

    Evrard, B; Chiap, P; DeTullio, P; Ghalmi, F; Piel, G; Van Hees, T; Crommen, J; Losson, B; Delattre, L

    2002-12-13

    Albendazole (ABZ) is a benzimidazole derivative with a broad spectrum of activity against human and animal helminthe parasites. ABZ has a very poor aqueous solubility. This study shows that hydroxypropyl-beta-cyclodextrin (HP-beta-CD) is able to form inclusion complexes with ABZ and that is able to increase its aqueous solubility. A synergistic effect exists between HP-beta-CD and citric acid. The combination of HP-beta-CD (200 mM) and citric acid (50 mM) allows dissolution of more than 1.5 mg of ABZ per ml. The aim of this study is the in vivo evaluation in sheep of a solution of the inclusion complex of ABZ with HP-beta-CD in comparison with a suspension of the same drug. A significant (P<0.05) increase in the relative bioavailability is obtained with the solution containing the ABZ-HP-beta-CD complex as measured by ABZSO plasma levels. The area under the curve (AUC(0--> proportional, variant )) of the solution is 37% higher than that obtained with the suspension. Likewise the peak plasma concentration (C(max)) is twice that of the solution while the time to reach C(max) (T(max)) is reduced. PMID:12480310

  12. Degradation of Surfactants in Hydroponic Wheat Root Zones

    NASA Astrophysics Data System (ADS)

    Monje, Oscar; McCoy, Lashelle; Flanagan, Aisling

    Hygiene water recycling in recirculating hydroponic systems can be enhanced by plant roots by providing a substrate and root exudates for bacterial growth. However, reduced plant growth can occur during batch mode additions of high concentrations of surfactant. An analog hygiene water stream containing surfactants (Steol CS330, Mirataine CB) was added to a hydroponically-grown wheat plant root zone. The plants were grown at 700 mol mol-1 CO2, a photosynthetic photon flux of 300 mol m-2 s-1, and a planting density of 380 plants m-2. Volumetric oxygen mass transfer coefficients were determined using the fermentative/dynamic outgassing method to maintain adequate oxygen mass transfer rates in the root zone. This analysis suggested an optimal flow rate of the hydroponic solution of 5 L min-1. The hydroponic system was inoculated with biofilm from a bioreactor and rates of surfactant degradation were measured daily based on reduction in chemical oxygen demand (COD). The COD decreased from 400 to 100 mg L-1 after 2 days following batch addition of the analog hygiene water to the hydroponic system. Measurements of dissolved oxygen concentration and solution temperature suggest that the root zone was provided adequate aeration to meet both oxygen demands from plant and microbial respiration during the degradation of the surfactant. Results from this study show that hydroponic systems can be used to enhance rates of hygiene water processing.

  13. Water-soluble beta-cyclodextrins in paediatric oral solutions of spironolactone: preclinical evaluation of spironolactone bioavailability from solutions of beta-cyclodextrin derivatives in rats.

    PubMed

    Kaukonen, A M; Lennernäs, H; Mannermaa, J P

    1998-06-01

    Water-soluble derivatives of beta-cyclodextrin have been considered for solubilization of spironolactone in the formulation of a safe liquid preparation for premature infants. The oral absorption of spironolactone was studied in rats to evaluate the need to adjust spironolactone dosage in prospective clinical studies. Spironolactone was administered in solutions of sulphobutyl ether beta-cyclodextrin (SBE7) or dimethyl-beta-cyclodextrin (DM-beta-CyD) and also as spironolactone-containing powder papers (reference preparation). Spironolactone in SBE7 solution was administered intravenously to assess the extent of intestinal absorption from the different formulations. Spironolactone and the metabolites 7alpha-thiospirolactone, 7alpha-thiomethylspirolactone and canrenone were determined in rat serum after intravenous administration of spironolactone. Half-lives for spironolactone, 7alpha-thiomethylspirolactone and canrenone were 0.72 +/- 0.17, 1.5 +/- 0.3 and 2.2 +/- 0.3 h, respectively. Although, according to Cmax values, 7alpha-thiomethylspirolactone was the major serum metabolite in rats, higher AUC (area under the serum concentration-time curve) values were obtained for canrenone. After oral administration of spironolactone the bioavailabilities evaluated from the AUC values of 7alpha-thiomethylspirolactone were 27.5 +/- 9.3%, 81.3 +/- 28.8% and 82.8 +/- 28.6% for powder papers, DM-beta-CyD and SBE7 solutions, respectively. The oral absorption of spironolactone by rats was better after administration of spironolactone in SBE7 and DM-beta-CyD solutions than after administration as powder papers. Both cyclodextrin formulations enhanced spironolactone bioavailability to a similar extent despite some deacetylation of spironolactone in the presence of SBE7. A reduction of spironolactone dosage would be recommended during clinical studies with premature infants. These results indicate that SBE7 could be a safe and suitable excipient for the solubilization of

  14. Exploring Classroom Hydroponics. Growing Ideas.

    ERIC Educational Resources Information Center

    National Gardening Association, Burlington, VT.

    Growing Ideas, the National Gardening Association's series for elementary, middle, and junior high school educators, helps teachers engage students in using plants and gardens as contexts for developing a deeper, richer understanding of the world around them. This volume's focus is on hydroponics. It presents basic hydroponics information along…

  15. A recirculating hydroponic system for studying peanut (Arachis hypogaea L.)

    NASA Technical Reports Server (NTRS)

    Mackowiak, C. L.; Wheeler, R. M.; Stutte, G. W.; Yorio, N. C.; Ruffe, L. M.; Sager, J. C. (Principal Investigator)

    1998-01-01

    Peanut (Arachis hypogaea L.) plants were grown hydroponically, using continuously recirculating nutrient solution. Two culture tray designs were tested; one tray design used only nutrient solution, while the other used a sphagnum-filled pod development compartment just beneath the cover and above the nutrient solution. Both trays were fitted with slotted covers to allow developing gynophores to reach the root zone. Peanut seed yields averaged 350 gm-2 dry mass, regardless of tray design, suggesting that substrate is not required for hydroponic peanut production.

  16. Nutrient Management in Recirculating Hydroponic Culture

    NASA Technical Reports Server (NTRS)

    Bugbee, Bruce

    2004-01-01

    There is an increasing need to recirculate and reuse nutrient solutions in order to reduce environmental and economic costs. However, one of the weakest points in hydroponics is the lack of information on managing the nutrient solution. Many growers and research scientists dump out nutrient solutions and refill at weekly intervals. Other authors have recommended measuring the concentrations of individual nutrients in solution as a key to nutrient control and maintenance. Dumping and replacing solution is unnecessary. Monitoring ions in solution is not always necessary; in fact the rapid depletion of some nutrients often causes people to add toxic amounts of nutrients to the solution. Monitoring ions in solution is interesting, but it is not the key to effective maintenance.

  17. Determination of selenium bioavailability to a benthic bivalve from particulate and solute pathways

    USGS Publications Warehouse

    Luoma, S.N.; Johns, C.; Fisher, N.S.; Steinberg, N.A.; Oremland, R.S.; Reinfelder, J.R.

    1992-01-01

    Particulate organo-Se was assimilated with 86% efficiency by the deposit feeding bivalve Macoma balthica, when the clam was fed 75Se-labeled diatoms. Absorption efficiencies of participate elemental Se were 22%, when the animals were fed 75Se-labeled sediments in which elemental Se was precipitated by microbial dissimilatory reduction. Precipitation of elemental Se did not eliminate biological availability of the element. Selenite was taken up from solution slowly by M. balthica (mean concentration factor was 712). Concentrations of selenite high enough to influence Se bioaccumulation by M. balthica did not occur in the oxidized water column of San Francisco Bay. However, 98-99% of the Se observed in M. balthica could be explained by ingestion of the concentrations of participate Se found in the bay. The potential for adverse biological effects occurred at much lower concentrations of environmental Se when food web transfer was considered than when predictions of effects were based upon bioassays with solute forms of the element. Selenium clearly requires a protective criterion based upon particulate concentrations or food web transfer. ?? 1992 American Chemical Society.

  18. Automated sensing of hydroponic macronutrients using a computer-controlled system with an array of ion-selective electrodes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Hydroponic production systems grow plants without soil, relying on a circulating solution to provide the necessary nutrients. Maintaining an optimum nutrient balance in this solution is important for maximizing crop growth and yield. Particularly in closed hydroponic systems it is important to monit...

  19. Evaluation of Skin Penetration of Diclofenac from a Novel Topical Non Aqueous Solution: A Comparative Bioavailability Study

    PubMed Central

    Nivsarkar, Manish; Patel, Ketan R.; Patel, Dixit D.

    2015-01-01

    Introduction Different topical formulations of diclofenac have varying skin penetration profile. Recent advances in science and technology has led to the development of many new formulations of drugs for topical drug delivery. One such technological development has led to the innovation of Dynapar QPS, a novel, non-aqueous, quick penetrating solution (QPS) of diclofenac diethylamine. Aim This study was aimed to measure the total exposure from the drug penetrating the skin in healthy human subjects and comparing the relative systemic bioavailability of Dynapar QPS® with diclofenac emulgel. Materials and Methods A 200 mg of diclofenac from either Dynapar QPS® (5 ml) or emulgel (20 g) was applied on back of subject as per the randomisation schedule. Blood samples were collected up to 16 hours post drug application. Plasma concentration of diclofenac was measured by pre-validated HPLC method. Pharmacokinetic (PK) parameters like Cmax, Tmax, t1/2, AUC0-t, AUC0-∞, and Kel, of diclofenac were determined for both the formulations. Results Mean Cmax after administration of Dynapar QPS® and diclofenac emulgel were 175.93 and 40.04 ng/ml, respectively. Tmax of diclofenac was almost half with QPS compared to emulgel (5.24 hrs versus 9.53 hrs respectively). The mean AUC0–t and AUC0-∞ after administration of Dynapar QPS® was higher as compared to diclofenac emulgel (AUC0–t: 1224.19 versus 289.78 ng.h/ml, respectively; AUC0-∞: 1718.21 versus 513.83 ng.h/ml, respectively). None of the subject experienced any adverse event during the study. Conclusion The results indicate an enhanced penetration and subsequent absorption of diclofenac from Dynapar QPS® as compared to diclofenac emulgel. Higher penetration is likely to translate into better pain relief in patients. PMID:26816910

  20. Bioavailability and generic prescribing.

    PubMed

    Mindel, J S

    1976-01-01

    Although oral drug bioinequivalence has been attributed to a number of causes (excipients, dosage form, variation in dissolution time, and aging) less is known about bioavailability problems of topical medications in ophthalmology. Factors that can alter drug absorption from solutions (pH, partition coefficient, container impurities, contact time, etc.) are noted, and cases in which bioavailability problems should be considered as causes of therapeutic failure are discussed. Various attitudes representing pharmaceutical companies, the federal government, pharmacists, consumers and physicians toward the related problems of bioinequivalence and generic prescribing are examined. Techniques for in vivo and in vitro drug testing and for establishing uniform conditions of drug manufacture and storage can contribute to identification and minimization of bioavailability problems. A rational program based on a combination of such techniques could, ultimately, lead to establishment of the terms "generic equivalency" and "therapeutic equivalency" as synonymous. PMID:13505

  1. Hydroponic Feed With Suction

    NASA Technical Reports Server (NTRS)

    Cox, William M.; Brown, Christopher S.; Dreschel, Thomas W.

    1994-01-01

    Placing nutrient solution under suction increases growth. Foam plug seals growing stem of plant, making it possible to maintain suction in nutrient liquid around roots. Jar wrapped in black tape to keep out light. Potential use in terrestrial applications in arid climates or in labor-intensive agricultural situations.

  2. Hydroponic phytoremediation of heavy metals and radionuclides

    SciTech Connect

    Hartong, J.; Szpak, J.; Hamric, T.; Cutright, T.

    1998-07-01

    It is estimated that the Departments of Defense, Energy, and Agriculture will spend up to 300 billion federal dollars on environmental remediation during the next century. Current remediation processes can be expensive, non-aesthetic, and non-versatile. Therefore, the need exists for more innovative and cost effective solutions. Phytoremediation, the use of vegetation for the remediation of contaminated sediments, soils, and ground water, is an emerging technology for treating several categories of persistent, toxic contaminants. Although effective, phytoremediation is still in a developmental stage, and therefore is not a widely accepted technology by regulatory agencies and public groups. Research is currently being conducted to validate the processes effectiveness as well as increase regulatory and community acceptance. This research will focus on the ability of plants to treat an aquifer contaminated with heavy metals and radionuclides. Specifically, the effectiveness of hydroponically grown dwarf sunflowers and mustard seed will be investigated.

  3. Hydroponics--Studies in Plant Culture With Historical Roots.

    ERIC Educational Resources Information Center

    Lopez, Luz Maria

    1981-01-01

    Presents methods for demonstrating and applying scientific principles by growing plants through water culture (hydroponics), including a review of the history of hydroponics, re-creating some early experiments, and setting up a modern hydroponic system. (CS)

  4. A hydroponic design for microgravity and gravity installations

    NASA Technical Reports Server (NTRS)

    Fielder, Judith; Leggett, Nickolaus

    1990-01-01

    A hydroponic system is presented that is designed for use in microgravity or gravity experiments. The system uses a sponge-like growing medium installed in tubular modules. The modules contain the plant roots and manage the flow of the nutrient solution. The physical design and materials considerations are discussed, as are modifications of the basic design for use in microgravity or gravity experiments. The major external environmental requirements are also presented.

  5. Use of Hydrogen Peroxide to Disinfect Hydroponic Plant Growth Systems

    NASA Technical Reports Server (NTRS)

    Barta, Daniel J.; Henderson, Keith

    2000-01-01

    Hydrogen peroxide was studied as an alternative to conventional bleach and rinsing methods to disinfect hydroponic plant growth systems. A concentration of 0.5% hydrogen peroxide was found to be effective. Residual hydrogen peroxide can be removed from the system by repeated rinsing or by flowing the solution through a platinum on aluminum catalyst. Microbial populations were reduced to near zero immediately after treatment but returned to pre-disinfection levels 2 days after treatment. Treating nutrient solution with hydrogen peroxide and planting directly into trays being watered with the nutrient solution without replenishment, was found to be detrimental to lettuce germination and growth.

  6. Hormonal regulation of wheat growth during hydroponic culture

    NASA Technical Reports Server (NTRS)

    Wetherell, Donald

    1988-01-01

    Hormonal control of root growth has been explored as one means to alleviate the crowding of plant root systems experienced in prototype hydroponic biomass production chambers being developed by the CELSS Breadboard Project. Four plant hormones, or their chemical analogs, which have been reported to selectively inhibit root growth, were tested by adding them to the nutrient solutions on day 10 of a 25 day growth test using spring wheat in hydroponic cultures. Growth and morphological changes is both shoot and root systems were evaluated. In no case was it possible to inhibit root growth without a comparable inhibition of shoot growth. It was concluded that this approach is unlikely to prove useful for wheat.

  7. A Simplified Integrated Fish Culture Hydroponics System.

    ERIC Educational Resources Information Center

    Emberger, Gary

    1991-01-01

    Investigations that facilitate experimental design, the concept of replication, data analysis, and other aspects of scientific study are described. A list of materials, the recommended plants, and the directions for building the hydroponics unit are included. (KR)

  8. Hydroponic Crop Production using Recycled Nutrients from Inedible Crop Residues

    NASA Technical Reports Server (NTRS)

    Garland, Jay L.; Mackowiak, Cheryl L.; Sager, John C.

    1993-01-01

    The coupling of plant growth and waste recycling systems is an important step toward the development of bioregenerative life support systems. This research examined the effectiveness of two alternative methods for recycling nutrients from the inedible fraction (residue) of candidate crops in a bioregenerative system as follows: (1) extraction in water, or leaching, and (2) combustion at 550 C, with subsequent reconstitution of the ash in acid. The effectiveness of the different methods was evaluated by (1) comparing the percent recovery of nutrients, and (2) measuring short- and long-term plant growth in hydroponic solutions, based on recycled nutrients.

  9. Calcium Binding to Amino Acids and Small Glycine Peptides in Aqueous Solution: Toward Peptide Design for Better Calcium Bioavailability.

    PubMed

    Tang, Ning; Skibsted, Leif H

    2016-06-01

    Deprotonation of amino acids as occurs during transfer from stomach to intestines during food digestion was found by comparison of complex formation constants as determined electrochemically for increasing pH to increase calcium binding (i) by a factor of around 6 for the neutral amino acids, (ii) by a factor of around 4 for anions of the acidic amino acids aspartic and glutamic acid, and (iii) by a factor of around 5.5 for basic amino acids. Optimized structures of the 1:1 complexes and ΔHbinding for calcium binding as calculated by density functional theory (DFT) confirmed in all complexes a stronger calcium binding and shorter calcium-oxygen bond length in the deprotonated form. In addition, the stronger calcium binding was also accompanied by a binding site shift from carboxylate binding to chelation by α-amino group and carboxylate oxygen for leucine, aspartate, glutamate, alanine, and asparagine. For binary amino acid mixtures, the calcium-binding constant was close to the predicted geometric mean of the individual amino acid binding constants indicating separate binding of calcium to two amino acids when present together in solution. At high pH, corresponding to conditions for calcium absorption, the binding affinity increased in the order Lys < Arg < Cys < Gln < Gly ∼ Ala < Asn < His < Leu < Glu< Asp. In a series of glycine peptides, calcium-binding affinity was found to increase in the order Gly-Leu ∼ Gly-Gly < Ala-Gly < Gly-His ∼ Gly-Lys-Gly < Glu-Cys-Gly < Gly-Glu, an ordering confirmed by DFT calculations for the dipeptides and which also accounted for large synergistic effects in calcium binding for up to 6 kJ/mol when compared to the corresponding amino acid mixtures. PMID:27159329

  10. Uniformity of environmental conditions and plant growth in a hydroponic culture system for use in a growth room with aerial CO2 control

    NASA Technical Reports Server (NTRS)

    Vessey, J. K.; York, E. K.; Henry, L. T.; Raper, C. D. Jr; Raper CD, J. r. (Principal Investigator)

    1988-01-01

    A portable system of hydroponic culture was developed that maintained temperature, pH, and nutrient concentrations of circulating nutrient solutions. The hydroponic system is used within a controlled-environment room (CER) for control of aerial environment. The CER was equipped with an auto-calibrating system for atmospheric CO2 control. The control systems for the hydroponic chambers were able to maintain acidity within +/- 0.2 pH units and the temperature with +/- 0.5 degree C. Mixing time for the 200-liter volume of solution within a hydroponic chamber was less than 12 min. The CO2 control system was able to maintain aerial concentrations within +/- 10 ppm CO2 during the light period. The only gradient found to occur within the hydroponic chambers or CER was a slight gradient in aerial temperature along the length of hydroponic chambers. Growth of soybeans [Glycine max (L.) Merr.] was characterized during a 3-week period of vegetative development by leaf number and area, plant dry weight, total N content of plants, and N depletion from the nutrient solution. The growth characteristics among populations for three hydroponic chambers within the CER were not significantly different, and the percent standard errors of means of the measurements within populations from each chamber were nearly all less than 10%. Thus, the uniformity of plant growth reflected the uniformity of environmental conditions.

  11. Wheat response to differences in water and nutritional status between zeoponic and hydroponic growth systems

    NASA Technical Reports Server (NTRS)

    Steinberg, S. L.; Ming, D. W.; Henderson, K. E.; Carrier, C.; Gruener, J. E.; Barta, D. J.; Henninger, D. L.

    2000-01-01

    Hydroponic culture has traditionally been used for controlled environment life support systems (CELSS) because the optimal environment for roots supports high growth rates. Recent developments in zeoponic substrate and microporous tube irrigation (ZPT) also offer high control of the root environment. This study compared the effect of differences in water and nutrient status of ZPT or hydroponic culture on growth and yield of wheat (Triticum aestivum L. cv. USU-Apogee). In a side-by-side test in a controlled environment, wheat was grown in ZPT and recirculating hydroponics to maturity. Water use by plants grown in both culture systems peaked at 15 to 20 L m-2 d-1 up to Day 40, after which it declined more rapidly for plants grown in ZPT culture due to earlier senescence of leaves. No consistent differences in water status were noted between plants grown in the two culture systems. Although yield was similar, harvest index was 28% lower for plants grown in ZPT than in hydroponic culture. Sterile green tillers made up 12 and 0% of the biomass of plants grown in ZPT and hydroponic culture, respectively. Differences in biomass partitioning were attributed primarily to NH4-N nutrition of plants grown in ZPT compared with NO3-N in hydroponic nutrient solution. It is probable that NH4-N-induced Ca deficiency produced excess tillering and lower harvest index for plants grown in ZPT culture. These results suggest that further refinements in zeoponic substrate would make ZPT culture a viable alternative for achieving high productivity in a CELSS.

  12. Wheat Response to Differences In Water and Nutritional Status Between Zeoponic and Hydroponic Growth Systems

    NASA Technical Reports Server (NTRS)

    Steinberg, Susan L.; Ming, Douglas W.; Henderson, Keith E.; Carrier, Chris; Gruener, John E.; Barta, Dan J.; Henninger, Don L.

    1999-01-01

    Hydroponic culture has traditionally been used for controlled environment life support systems (CELSS) because the optimal environment for roots supports high growth rates. Recent developments in zeoponic substrate and microporous tube irrigation (ZPT) also offer high control of the root environment. This study compared the effect of differences in water and nutrient status of ZPT or hydroponic culture on growth and yield of wheat (Triticum aestivum L., CV 'USU-Apogee'). In a side-by-side test in a controlled environment, wheat was grown in ZPT and recirculating hydroponics to maturity. Water use by plants grown in both culture systems peaked at 15-20 L per square meters per d up to day 40, after which it declined more rapidly for plants grown in ZPT culture due to earlier senescence of leaves. No consistent differences were noted in water status between plants grown in the two culture systems. Although yield was similar, harvest index was 28% lower for plants grown in ZPT versus hydroponic culture. Sterile green tillers made up 12% and 0% of the biomass of plants grown in ZPT and hydroponic culture, respectively. Differences in biomass partitioning were attributed primarily to NH4 -N nutrition of plants grown in ZPT as compared with NO3-N in hydroponic nutrient solution. It was likely that NH4-N induced Ca deficiency produced excess tillering and lower harvest index for plants grown in ZPT culture. These results suggest that further refinements in zeoponic substrate would make ZPT culture a viable alternative for achieving high productivity in a CELSS.

  13. Wheat response to differences in water and nutritional status between zeoponic and hydroponic growth systems.

    PubMed

    Steinberg, S L; Ming, D W; Henderson, K E; Carrier, C; Gruener, J E; Barta, D J; Henninger, D L

    2000-01-01

    Hydroponic culture has traditionally been used for controlled environment life support systems (CELSS) because the optimal environment for roots supports high growth rates. Recent developments in zeoponic substrate and microporous tube irrigation (ZPT) also offer high control of the root environment. This study compared the effect of differences in water and nutrient status of ZPT or hydroponic culture on growth and yield of wheat (Triticum aestivum L. cv. USU-Apogee). In a side-by-side test in a controlled environment, wheat was grown in ZPT and recirculating hydroponics to maturity. Water use by plants grown in both culture systems peaked at 15 to 20 L m-2 d-1 up to Day 40, after which it declined more rapidly for plants grown in ZPT culture due to earlier senescence of leaves. No consistent differences in water status were noted between plants grown in the two culture systems. Although yield was similar, harvest index was 28% lower for plants grown in ZPT than in hydroponic culture. Sterile green tillers made up 12 and 0% of the biomass of plants grown in ZPT and hydroponic culture, respectively. Differences in biomass partitioning were attributed primarily to NH4-N nutrition of plants grown in ZPT compared with NO3-N in hydroponic nutrient solution. It is probable that NH4-N-induced Ca deficiency produced excess tillering and lower harvest index for plants grown in ZPT culture. These results suggest that further refinements in zeoponic substrate would make ZPT culture a viable alternative for achieving high productivity in a CELSS. PMID:11543523

  14. Hydroponic cultivation offers a practical means of producing selenium-enriched garlic.

    PubMed

    Tsuneyoshi, Tadamitsu; Yoshida, Jiro; Sasaoka, Takashi

    2006-03-01

    Garlic enriched by selenium (Se) could be an excellent source of dietary Se for cancer chemoprevention. The production of high-Se garlic requires Se-fertilized soil, but such soil may pollute the environment. Hydroponics is a closed system that allows good control over Se fertilization without environmental consequences. We examined the effect of hydroponic cultivation on Se uptake and assimilation in garlic seedlings. Garlic bulbs were grown in the nutrient solution without Se for first 2 wk, and with potassium selenate for an additional week. Sulfate in an ordinary hydroponic solution inhibited the absorption and assimilation of selenate, but when a sulfate-free nutrient was used for Se addition, the garlic seedlings accumulated >1 mg Se, dry weight. Through HPLC inductively coupled plasma MS (HPLC-ICP-MS) analysis, Se-methlyselenocysteine (MeSeCys), gamma-glutamyl-Se-methlyselenocysteine (gamma-GluMeSeCys), selenomethionine, and nonmetabolized selenate were identified in water extracts of the garlic seedlings. The results demonstrate that hydroponic enrichment of Se in garlic seedlings could be a practical means of producing organic Se compounds for nutritional supplements. PMID:16484583

  15. Dieldrin uptake and translocation in plants growing in hydroponic medium.

    PubMed

    Murano, Hirotatsu; Otani, Takashi; Seike, Nobuyasu; Sakai, Mizuki

    2010-01-01

    It has been known that the Cucurbitaceae family takes up a large amount of persistent organic pollutants from soils and that the translocation of those compounds in cucurbits is higher than those in non-cucurbits. To understand the persistent organic pollutant uptake mechanisms of plant species, we compared the dieldrin absorption and transportation potentials of several plants in hydroponic medium. Sorghum (Sorghum vulgare Moench), sunflower (Helianthus annuus L.), soybean (Glycine max), komatsuna (Brassica rapa var. peruviridis), white-flowered gourd (Lagenaria siceraria var. hispida), cucumber (Cucumis sativus L.), and zucchini (Cucurbita pepo L.) were grown in a dieldrin-added hydroponic medium for 10 d, and then the amount of dieldrin in their shoots and roots was measured. All of the roots contained dieldrin, whereas only the cucurbits (white-flowered gourd, cucumber, and zucchini) contained considerable amounts of dieldrin in their shoots. The dieldrin uptake to the roots depended on the concentration of the n-hexane soluble components in the roots, regardless of whether the dieldrin in the roots was translocated to shoots or not. The dieldrin uptake from the solution to the roots was thought to be due to a passive response, such as adsorption on the roots. The translocation of dieldrin from the roots to the shoots was probably through the xylems. The amounts of dieldrin in the shoots per transpiration rates were higher for cucurbits than for non-cucurbits. It seems likely that cucurbits have uptake mechanisms for hydrophobic organic chemicals. PMID:20821429

  16. Monitoring And Controlling Hydroponic Flow

    NASA Technical Reports Server (NTRS)

    Dreschel, Thomas W.

    1992-01-01

    Pressure-monitoring and -controlling apparatus maintains slight suction required on nutrient solution in apparatus described in "Tubular Membrane Plant-Growth Unit" (KSC-11375), while overcoming gravity effects on operation of system on Earth. Suction helps to hold solution in tubular membrane.

  17. Hydroponic cultivation of soybean for Bioregenerative Life Support Systems (BLSSs)

    NASA Astrophysics Data System (ADS)

    De Pascale, Stefania; De Micco, Veronica; Aronne, Giovanna; Paradiso, Roberta

    evaluate the adaptation of soybean plants to hydroponics under controlled environment, as well as the plant response to changing cultural parameters, in order to identify the best cultivation protocol for BLSSs. The optimisation of growth conditions in hydroponics has been pursued being aware that environmental factors acting at sub-optimal levels may also increase the sensitivity of plants to space factors. The influence of the following parameters on plant growth and yield was also studied: - the hydroponic system: sole liquid solution (Nutrient Film Technique, NFT) vs solid substrate (rockwool); - the source of nitrogen in the nutrient solution: nitrate fertilizers vs urea; - the root symbiosis with atmospheric nitrogen-fixing bacteria: absence or presence of Bradyrhizobium japonicum; - the influence of microbes in the rhizosphere: inoculation with a mix containing mycorrhizal and trichoderma species, and beneficial bacteria vs a non-inoculated control. All the treatments were evaluated in terms of agronomic traits (e.g. plant size and seed production), physiological traits (gas exchange, nutrient uptake), chemical composition of seeds and their products, and technical parameters such as resource use efficiency and non-edible biomass production (waste).

  18. Temperature and pH effects on plant uptake of benzotriazoles by sunflowers in hydroponic culture.

    PubMed

    Castro, Sigifredo; Davis, Lawrence C; Erickson, Larry E

    2004-01-01

    This article describes a systematic approach to understanding the effect of environmental variables on plant uptake (phyto-uptake) of organic contaminants. Uptake (and possibly phytotransformation) of xenobiotics is a complex process that may differ from nutrient uptake. A specific group of xenobiotics (benzotriazoles) were studied using sunflowers grown hydroponically with changes of environmental conditions including solution volume, temperature, pH, and mixing. The response of plants to these stimuli was evaluated and compared using physiological changes (biomass production and water uptake) and estimated uptake rates (influx into plants), which define the uptake characteristics for the xenobiotic. Stirring of the hydroponic solution had a significant impact on plant growth and water uptake. Plants were healthier, probably because of a combination of factors such as improved aeration and increase in temperature. Uptake and possibly phytotransformation of benzotriazoles was increased accordingly. Experiments at different temperatures allowed us to estimate an activation energy for the reaction leading to triazole disappearance from the solution. The estimated activation energy was 43 kJ/mol, which indicates that the uptake process is kinetically limited. Culturing plants in triazole-amended hydroponic solutions at different pH values did not strongly affect the biomass production, water uptake, and benzotriazole uptake characteristics. The sunflowers showed an unexpected capacity to buffer the solution pH. PMID:15554474

  19. Search for a plant for phytoremediation--what can we learn from field and hydroponic studies?

    PubMed

    Zabłudowska, E; Kowalska, J; Jedynak, L; Wojas, S; Skłodowska, A; Antosiewicz, D M

    2009-10-01

    The main aim of the study was to evaluate the strategies for coping with arsenic toxicity developed by the mine species (Calamagrostis arundinacea, Fragaria vesca, Stachys sylvatica, and Epilobium parviflorum), and to compare results obtained from plants exposed to arsenic present in contaminated soil (2000-3500 mg/kg dw) and in hydroponic solution (2 microM and 12 microM arsenate). Here we report basic differences in plant responses to arsenic depending on growth conditions (hydroponic/soil) with respect to uptake, root-to-shoot translocation, distribution, and detoxification/speciation. Calamagrostis has the highest level of As-tolerance among the tested species. When grown in soil, it accumulated the highest amount of As in roots and shoots relative to other species, however, when exposed to arsenic in hydroponics, it had lower As concentrations. The efficiency of arsenic root-to-shoot translocation was also different, being less effective in soil-grown Calamagrostis compared with hydroponics. Furthermore, in Calamagrostis exposed to arsenate in liquid medium, As(III) was the predominant arsenic form, in contrast to plants grown in As-contaminated soil, in which As(V) predominated. In addition, comparison of the level of phytochelatins showed that only PC2 was detected in plants from hydroponics, whereas in those from soil, additionally PC3 and PC4 were found. The results show that the basic components of a plant's response to arsenic, including uptake, accumulation as well as detoxification, change depending on the experimental conditions (arsenic in liquid medium or contaminated soil). PMID:19733893

  20. Wheat phytotoxicity from arsenic and cadmium separately and together in solution culture and in a calcareous soil

    SciTech Connect

    Cao, Q; Hu, Q; Khan, S; Wang, Z; Lin, A; Du, X; Zhu, Y

    2007-03-05

    The toxicity effect of two deleterious elements of arsenic (As) and cadmium (Cd) (individually or in combination) on root elongation of wheat seedlings (Triticum aestivum, L.) were investigated both in hydroponics and in soils freshly spiked with the toxic elements. Median effective concentration (EC{sub 50}) and non-observed effect concentration (NOEC) were used to investigate the toxic thresholds and potencies of the two elements. The EC{sub 50} for As was 0.97 {mu}M in hydroponics and 196 mg {center_dot} kg{sup -1} in soil, and 4.32 {mu}M and 449 mg {center_dot} kg{sup -1} for Cd, respectively. Toxic unit (TU) and additive index (AI) concepts were introduced to determine the combined outcomes, and different behaviors were obtained: synergism in solution culture (EC{sub 50mix} = 0.36 TU{sub mix} and AI: 1.76) and antagonism in soil experiments (EC{sub 50mix} = 1.49 TU{sub mix} and AI: -0.33). Furthermore, the data of soil bioavailable As and Cd can not explain the discrepancy between the results derived from soil and hydroponics experiments.

  1. Bacterial community analysis of Tatsoi cultivated by hydroponics.

    PubMed

    Koo, Ok K; Kim, Hun; Kim, Hyun J; Baker, Christopher A; Ricke, Steven C

    2016-07-01

    Tatsoi (Brassica narinosa) is a popular Asian salad green that is mostly consumed as a source of fresh produce. The purpose of this study was to assess the microbial diversity of Tatsoi cultivated in a hydroponic system and of its ecosystem. Tatsoi leaves, nutrient solution, and perlite/earth samples from a trickle feed system (TFS) and an ebb-and-flow system (EFS) were collected and their microbial communities were analyzed by pyrosequencing analysis. The results showed that most bacteria in the leaves from the TFS contained genus Sporosarcina (99.6%), while Rhizobium (60.4%) was dominant in the leaves from the EFS. Genus Paucibacter (18.21%) and Pelomonas (12.37%) were the most abundant microbiota in the nutrient solution samples of the TFS. In the EFS, the nutrient solution samples contained mostly genus Rhodococcus and Acinetobacter. Potential microbial transfer between the leaves and the ecosystem was observed in the EFS, while samples in the TFS were found to share only one species between the leaves, nutrient solution, and earth. Together, these results show that the bacterial populations in Tatsoi and in its ecosystem are highly diverse based on the cultivation system. PMID:27070460

  2. Selenium addition alters mercury uptake, bioavailability in the rhizosphere and root anatomy of rice (Oryza sativa)

    PubMed Central

    Wang, Xun; Tam, Nora Fung-Yee; Fu, Shi; Ametkhan, Aray; Ouyang, Yun; Ye, Zhihong

    2014-01-01

    Background and Aims Mercury (Hg) is an extremely toxic pollutant, especially in the form of methylmercury (MeHg), whereas selenium (Se) is an essential trace element in the human diet. This study aimed to ascertain whether addition of Se can produce rice with enriched Se and lowered Hg content when growing in Hg-contaminated paddy fields and, if so, to determine the possible mechanisms behind these effects. Methods Two cultivars of rice (Oryza sativa, japonica and indica) were grown in either hydroponic solutions or soil rhizobags with different Se and Hg treatments. Concentrations of total Hg, MeHg and Se were determined in the roots, shoots and brown rice, together with Hg uptake kinetics and Hg bioavailability in the soil. Root anatonmy was also studied. Key Results The high Se treatment (5 μg g–1) significantly increased brown rice yield by 48 % and total Se content by 2·8-fold, and decreased total Hg and MeHg by 47 and 55 %, respectively, compared with the control treatments. The high Se treatment also markedly reduced ‘water-soluble’ Hg and MeHg concentrations in the rhizosphere soil, decreased the uptake capacity of Hg by roots and enhanced the development of apoplastic barriers in the root endodermis. Conclusions Addition of Se to Hg-contaminated soil can help produce brown rice that is simultaneously enriched in Se and contains less total Hg and MeHg. The lowered accumulation of total Hg and MeHg appears to be the result of reduced bioavailability of Hg and production of MeHg in the rhizosphere, suppression of uptake of Hg into the root cells and an enhancement of the development of apoplastic barriers in the endodermis of the roots. PMID:24948669

  3. Nutritional status and ion uptake response of Gynura bicolor DC. between Porous-tube and traditional hydroponic growth systems

    NASA Astrophysics Data System (ADS)

    Wang, Minjuan; Fu, Yuming; Liu, Hong

    2015-08-01

    Hydroponic culture has traditionally been used for Bioregenerative Life Support Systems (BLSS) because the optimal environment for roots supports high growth rates. Recent developments in Porous-tube Nutrient Delivery System (PTNDS) also offer high control of the root environment which is designed to provide a means for accurate environmental control and to allow for two-phase flow separation in microgravity. This study compared the effects of PTNDS and traditional hydroponic cultures on biomass yield, nutritional composition and antioxidant defense system (T-AOC, GSH, H2O2 and MDA) of G. bicolor, and ionic concentration (NH4+, K+, Mg2+, Ca2+, NO3-, H2 PO4-, SO42-) of nutrient solution during planting period in controlled environment chambers. The results indicated that the biomass production and yield of G. bicolor grown in PTNDS were higher than in hydroponic culture, although Relative water content (RWC), leaf length and shoot height were not significantly different. PTNDS cultivation enhanced calories from 139.5 to 182.3 kJ/100 g dry matter, and carbohydrate from 4.8 to 7.3 g/100 g dry matter and reduced the amount of protein from 7.3 to 4.8 g/100 g dry matter and ash from 1.4 to1.0 g/100 g dry matter, compared with hydroponic culture. PTNDS cultivation accumulated the nutrition elements of Ca, Cu, Fe and Zn, and reduced Na concentration. T-AOC and GSH contents were significantly lower in PTNDS than in hydroponic culture in the first harvest. After the first harvest, the contents of MDA and H2O2 were significantly higher in PTNDS than in hydroponic culture. However, the activity of T-AOC and GSH and H2O2 and MDA contents had no significant differences under both cultures after the second and third harvest. Higher concentrations of K+, Mg2+ and Ca2+ were found in nutrient solution of plants grown in hydroponics culture compared to PTNDS, wherein lower concentrations of NO3-, H2 PO4- and SO42- occurred. Our results demonstrate that PTNDS culture has more

  4. Production of deuterated switchgrass by hydroponic cultivation

    SciTech Connect

    Evans, Barbara R.; Bali, Garima; Foston, Marcus B.; Ragauskas, Arthur J.; O'Neill, Hugh Michael; Shah, Riddhi S.; McGaughey, Joseph; Reeves, David T.; Rempe, Caroline S.; Davison, Brian H.

    2015-04-21

    Deuterium enrichment of biological materials can potential enable expanded experimental use of small angle neutron scattering (SANS) to investigate molecular structural transitions of complex systems such as plant cell walls. Two key advances have been made that facilitate cultivation of switchgrass, an important forage and biofuel crop, for controlled isotopic enrichment: (1) perfusion system with individual chambers and (2) hydroponic growth from tiller cuttings. Plants were grown and maintained for several months with periodic harvest. Photosynthetic activity was monitored by measurement of CO2 in outflow from the growth chambers. Plant morphology and composition appeared normal compared to matched controls grown with H2O. Using this improved method, gram quantities of switchgrass leaves and stems were produced by continuous hydroponic cultivation using growth medium consisting of basal mineral salts in 50% D2O. Deuterium incorporation was confirmed by detection of the O-D and C-D stretching peaks with FTIR and quantified by 1H- and 2H-NMR. Lastly, this capability to produce deuterated lignocellulosic biomass under controlled conditions will enhance investigation of cell wall structure and its deconstruction by neutron scattering and NMR techniques.

  5. Production of deuterated switchgrass by hydroponic cultivation

    DOE PAGESBeta

    Evans, Barbara R.; Bali, Garima; Foston, Marcus B.; Ragauskas, Arthur J.; O'Neill, Hugh Michael; Shah, Riddhi S.; McGaughey, Joseph; Reeves, David T.; Rempe, Caroline S.; Davison, Brian H.

    2015-04-21

    Deuterium enrichment of biological materials can potential enable expanded experimental use of small angle neutron scattering (SANS) to investigate molecular structural transitions of complex systems such as plant cell walls. Two key advances have been made that facilitate cultivation of switchgrass, an important forage and biofuel crop, for controlled isotopic enrichment: (1) perfusion system with individual chambers and (2) hydroponic growth from tiller cuttings. Plants were grown and maintained for several months with periodic harvest. Photosynthetic activity was monitored by measurement of CO2 in outflow from the growth chambers. Plant morphology and composition appeared normal compared to matched controls grownmore » with H2O. Using this improved method, gram quantities of switchgrass leaves and stems were produced by continuous hydroponic cultivation using growth medium consisting of basal mineral salts in 50% D2O. Deuterium incorporation was confirmed by detection of the O-D and C-D stretching peaks with FTIR and quantified by 1H- and 2H-NMR. Lastly, this capability to produce deuterated lignocellulosic biomass under controlled conditions will enhance investigation of cell wall structure and its deconstruction by neutron scattering and NMR techniques.« less

  6. Integrating bioavailability approaches into waste rock evaluations

    USGS Publications Warehouse

    Ranville, James F.; Blumenstein, E. P.; Adams, Michael J.; Choate, LaDonna M.; Smith, Kathleen S.; Wildeman, Thomas R.

    2006-01-01

    The presence of toxic metals in soils affected by mining, industry, agriculture and urbanization, presents problems to human health, the establishment and maintenance of plant and animal habitats, and the rehabilitation of affected areas. A key to managing these problems is predicting the fraction of metal in a given soil that will be biologically labile, and potentially harmful ('bioavailable'). The molecular form of metals and metalloids, particularly the uncomplexed (free) form, controls their bioavailability and toxicity in solution. One computational approach for determining bioavailability, the biotic ligand model (BLM), takes into account not only metal complexation by ligands in solution, but also competitive binding of hardness cations (Ca 2+,Mg 2+,) and metal ions to biological receptor sites. The more direct approach to assess bioavailability is to explicitly measure the response of an organism to a contaminant. A number of microbial enzyme tests have been developed to assess the impact of pollution in a rapid and procedurally simple way. These different approaches in making bioavailability predictions may have value in setting landuse priorities, remediation goals, and habitat reclamation strategies.

  7. Root Zone Respiration on Hydroponically Grown Wheat Plant Systems

    NASA Technical Reports Server (NTRS)

    Soler-Crespo, R. A.; Monje, O. A.

    2010-01-01

    Root respiration is a biological phenomenon that controls plant growth and physiological development during a plant's lifespan. This process is dependent on the availability of oxygen in the system where the plant is located. In hydroponic systems, where plants are submerged in a solution containing vital nutrients but no type of soil, the availability of oxygen arises from the dissolved oxygen concentration in the solution. This oxygen concentration is dependent on the , gas-liquid interface formed on the upper surface of the liquid, as given by Henry's Law, depending on pressure and temperature conditions. Respiration rates of the plants rise as biomass and root zone increase with age. The respiration rate of Apogee wheat plants (Triticum aestivum) was measured as a function of light intensity (catalytic for photosynthesis) and CO2 concentration to determine their effect on respiration rates. To determine their effects on respiration rate and plant growth microbial communities were introduced into the system, by Innoculum. Surfactants were introduced, simulating gray-water usage in space, as another factor to determine their effect on chemical oxygen demand of microbials and on respiration rates of the plants. It is expected to see small effects from changes in CO2 concentration or light levels, and to see root respiration decrease in an exponential manner with plant age and microbial activity.

  8. Arsenic uptake and speciation in Arabidopsis thaliana under hydroponic conditions.

    PubMed

    Park, Jin Hee; Han, Young-Soo; Seong, Hye Jin; Ahn, Joo Sung; Nam, In-Hyun

    2016-07-01

    Arsenic (As) uptake and species in Arabidopsis thaliana were evaluated under hydroponic conditions. Plant nutrient solutions were treated with arsenite [As(III)] or arsenate [As(V)], and aqueous As speciation was conducted using a solid phase extraction (SPE) cartridge. Arabidopsis reduced As(V) to As(III) in the nutrient solution, possibly due to root exudates such as organic acids or the efflux of As(III) from plant roots after in vivo reduction of As(V) to As(III). Arsenic uptake by Arabidopsis was associated with increased levels of Ca and Fe, and decreased levels of K in plant tissues. Arsenic in Arabidopsis mainly occurred as As(III), which was coordinated with oxygen and sulfur based on XANES and EXAFS results. The existence of As(III)O and As(III)S in EXAFS indicates partial biotransformation of As(III)O to a sulfur-coordinated form because of limited amount of glutathione in plants. Further understanding the mechanism of As biotransformation in Arabidopsis may help to develop measures that can mitigate As toxicity via genetic engineering. PMID:27058920

  9. Integrating biological treatment of crop residue into a hydroponic sweetpotato culture.

    PubMed

    Trotman, A A; David, P P; Bonsi, C K; Hill, W A; Mortley, D G; Loretan, P A

    1997-01-01

    Residual biomass from hydroponic culture of sweetpotato [Ipomoea batatas (L.) Lam.] was degraded using natural bacterial soil isolates. Sweetpotato was grown for 120 days in hydroponic culture with a nutrient solution comprised of a ratio of 80% modified half Hoagland solution to 20% filtered effluent from an aerobic starch hydrolysis bioreactor. The phytotoxicity of the effluent was assayed with Waldmann's Green' lettuce (Lactuca sativa L.) and the ratio selected after a 60-day bioassay using sweetpotato plants propagated vegetatively from cuttings. Controlled environment chamber experiments were conducted to investigate the impact of filtrate from biological treatment of crop residue on growth and storage root production with plants grown in a modified half Hoagland solution. Incorporation of bioreactor effluent, reduced storage root yield of 'Georgia Jet' sweetpotato but the decrease was not statistically significant when compared with yield for plants cultured in a modified half Hoagland solution without filtrate. However, yield of 'TU-82-155' sweetpotato was significantly reduced when grown in a modified half Hoagland solution into which filtered effluent had been incorporated. Total biomass was significantly reduced for both sweetpotato cultivars when grown in bioreactor effluent. The leaf area and dry matter accumulation were significantly (P < 0.05) reduced for both cultivars when grown in solution culture containing 20% filtered effluent. PMID:11542554

  10. Integrating biological treatment of crop residue into a hydroponic sweetpotato culture

    NASA Astrophysics Data System (ADS)

    Trotman, A. A.; David, P. P.; Bonsi, C. K.; Hill, W. A.; Mortley, D. G.; Loretan, P. A.

    1997-01-01

    Residual biomass from hydroponic culture of sweetpotato [Ipomoea batatas (L.) Lam.] was degraded using natural bacterial soil isolates. Sweetpotato was grown for 120 days in hydroponic culture with a nutrient solution comprised of a ratio of 80% modified half Hoagland solution to 20% filtered effluent from an aerobic starch hydrolysis bioreactor. The phytotoxicity of the effluent was assayed with `Waldmann's Green' lettuce (Lactuca sativa L.) and the ratio selected after a 60-day bioassay using sweetpotato plants propagated vegetatively from cuttings. Controlled environment chamber experiments were conducted to investigate the impact of filtrate from biological treatment of crop residue on growth and storage root production with plants grown in a modified half Hoagland solution. Incorporation of bioreactor effluent, reduced storage root yield of `Georgia Jet' sweetpotato but the decrease was not statistically significant when compared with yield for plants cultured in a modified half Hoagland solution without filtrate. However, yield of `TU-82-155' sweetpotato was significantly reduced when grown in a modified half Hoagland solution into which filtered effluent had been incorporated. Total biomass was significantly reduced for both sweetpotato cultivars when grown in bioreactor effluent. The leaf area and dry matter accumulation were significantly (P < 0.05) reduced for both cultivars when grown in solution culture containing 20% filtered effluent.

  11. Protocol: optimising hydroponic growth systems for nutritional and physiological analysis of Arabidopsis thaliana and other plants

    PubMed Central

    2013-01-01

    Background Hydroponic growth systems are a convenient platform for studying whole plant physiology. However, we found through trialling systems as they are described in the literature that our experiments were frequently confounded by factors that affected plant growth, including algal contamination and hypoxia. We also found the way in which the plants were grown made them poorly amenable to a number of common physiological assays. Results The drivers for the development of this hydroponic system were: 1) the exclusion of light from the growth solution; 2) to simplify the handling of individual plants, and 3) the growth of the plant to allow easy implementation of multiple assays. These aims were all met by the use of pierced lids of black microcentrifuge tubes. Seed was germinated on a lid filled with an agar-containing germination media immersed in the same solution. Following germination, the liquid growth media was exchanged with the experimental solution, and after 14-21 days seedlings were transferred to larger tanks with aerated solution where they remained until experimentation. We provide details of the protocol including composition of the basal growth solution, and separate solutions with altered calcium, magnesium, potassium or sodium supply whilst maintaining the activity of the majority of other ions. We demonstrate the adaptability of this system for: gas exchange measurement on single leaves and whole plants; qRT-PCR to probe the transcriptional response of roots or shoots to altered nutrient composition in the growth solution (we demonstrate this using high and low calcium supply); producing highly competent mesophyll protoplasts; and, accelerating the screening of Arabidopsis transformants. This system is also ideal for manipulating plants for micropipette techniques such as electrophysiology or SiCSA. Conclusions We present an optimised plant hydroponic culture system that can be quickly and cheaply constructed, and produces plants with similar

  12. A thin film hydroponic system for plant studies

    NASA Technical Reports Server (NTRS)

    Hines, Robert; Prince, Ralph; Muller, Eldon; Schuerger, Andrew

    1990-01-01

    The Land Pavillion, EPCOT Center, houses a hydroponic, thin film growing system identical to that residing in NASA's Biomass Production Chamber at Kennedy Space Center. The system is targeted for plant disease and nutrition studies. The system is described.

  13. Human Folate Bioavailability

    PubMed Central

    Ohrvik, Veronica E.; Witthoft, Cornelia M.

    2011-01-01

    The vitamin folate is recognized as beneficial health-wise in the prevention of neural tube defects, anemia, cardiovascular diseases, poor cognitive performance, and some forms of cancer. However, suboptimal dietary folate intake has been reported in a number of countries. Several national health authorities have therefore introduced mandatory food fortification with synthetic folic acid, which is considered a convenient fortificant, being cost-efficient in production, more stable than natural food folate, and superior in terms of bioavailability and bioefficacy. Other countries have decided against fortification due to the ambiguous role of synthetic folic acid regarding promotion of subclinical cancers and other adverse health effects. This paper reviews recent studies on folate bioavailability after intervention with folate from food. Our conclusions were that limited folate bioavailability data are available for vegetables, fruits, cereal products, and fortified foods, and that it is difficult to evaluate the bioavailability of food folate or whether intervention with food folate improves folate status. We recommend revising the classical approach of using folic acid as a reference dose for estimating the plasma kinetics and relative bioavailability of food folate. PMID:22254106

  14. Controlled environment crop production - Hydroponic vs. lunar regolith

    NASA Technical Reports Server (NTRS)

    Bugbee, Bruce G.; Salisbury, Frank B.

    1989-01-01

    The potential of controlled environment crop production in a lunar colony is discussed. Findings on the effects of optimal root-zone and aerial environments derived as part of the NASA CELSS project at Utah State are presented. The concept of growing wheat in optimal environment is discussed. It is suggested that genetic engineering might produce the ideal wheat cultivar for CELSS (about 100 mm in height with fewer leaves). The Utah State University hydroponic system is outlined and diagrams of the system and plant container construction are provided. Ratio of plant mass to solution mass, minimum root-zone volume, maintenance, and pH control are discussed. A comparison of liquid hydrophonic systems and lunar regoliths as substrates for plant growth is provided. The physiological processes that are affected by the root-zone environment are discussed including carbon partitioning, nutrient availability, nutrient absorption zones, root-zone oxygen, plant water potential, root-produced hormones, and rhizosphere pH control.

  15. Arsenic Bioavailability, Bioaccessibility, And Speciation

    EPA Science Inventory

    The term bioavailability has many different meanings across various disciplines. Often bioavailability is concerned with human health aspects such as the case of urban children interacting with contaminated soil. The still utilized approach to base risk assessment on total meta...

  16. Response of hydroponically grown head lettuce on residual monomer from polyacrylamide.

    PubMed

    Mroczek, E; Konieczny, P; Kleiber, T; Waśkiewicz, A

    2014-01-01

    The aim was to assess acrylamide monomer (AMD) uptake by hydroponically grown lettuce. Lettuce was cultivated by applying plant tissue testing in a recycled system by the use of nutrient solutions prepared with two water-soluble flocculants F3 and F4 containing 176 and 763 mg kg(-1) of AMD, respectively. The effects on growth, fresh weight and plant leaf quality were evaluated by comparing these treatments and one control standard nutrient solution typically recommended for lettuce hydroponic cultivation. To assess the nutritional status of lettuce, samples were collected and lyophilised before determination of the selected micro- and macro-element contents. An HPLC with photodiode array detector method was applied to determine AMD in both selected flocculants and dried plant samples. Results show that lettuces cultivated under the conditions described above absorb AMD from nutrient solutions into their leaves. The AMD presence in recycled nutrient solutions has a negative influence on the growth of lettuce, reducing their average fresh weight and average number of leaves. The study confirmed that the problem of AMD mobility and its accumulation risk in plants should to be an important topic with respect to safe polyacrylamide (PAM) handling in the agro food area. PMID:24916210

  17. SLUDGE ORGANICS BIOAVAILABILITY

    EPA Science Inventory

    Concern over the bioavailability of toxic organics that can occur in municipal sludges threatens routine land application of sludge. vailable data, however, show that concentrations of priority organics in normal sludges are low. ludges applied at agronomic rates yield chemical c...

  18. Phytoremediation of lead using Ipomoea aquatica Forsk. in hydroponic solution.

    PubMed

    Bedabati Chanu, Laitonjam; Gupta, Abhik

    2016-08-01

    Ipomoea aquatica Forsk., an aquatic macrophyte, was assessed for its ability to accumulate lead (Pb) by exposing it to graded concentrations of this metal. Accumulation of Pb was the highest in root followed by that in stem and leaf with translocation factor (TF) values of less than unity. On the other hand, all bioconcentration factor (BCF) values in root, stem and leaf were greater than unity. Furthermore, exposure to Pb concentrations over about 20 mg L(-1) induced colour changes in the basal portion of stem which had significantly higher Pb accumulation than that in the unaffected apical part. This resulted in sequestration of excess metal in affected stem tissue, which could take up Pb by the process of caulofiltration or shoot filtration, and served as a secondary reservoir of Pb in addition to the root. The apical parts contained less lead and could regrow roots from nodes and survive when kept in Pb-free medium. The ability of the plant to store Pb in its root and lower part of stem coupled with its ability to propagate by fragmentation through production of adventitious roots and lateral branches from nodes raises the possibility of utilizing Ipomoea aquatica for Pb phytoremediation from liquid effluent. PMID:27186690

  19. Uptake of human pharmaceuticals by plants grown under hydroponic conditions.

    PubMed

    Herklotz, Patrick A; Gurung, Prakash; Vanden Heuvel, Brian; Kinney, Chad A

    2010-03-01

    Cabbage (Brassica rapa var. pekinensis) and Wisconsin Fast Plants (Brassica rapa) were chosen for a proof of concept study to determine the potential uptake and accumulation of human pharmaceuticals by plants. These plants were grown hydroponically under high-pressure sodium lamps in one of two groups including a control and test group exposed to pharmaceuticals. The control plants were irrigated with a recirculating Hoagland's nutrient solution while the test plants were irrigated with a Hoagland's nutrient solution fortified with the pharmaceuticals carbamazepine, salbutamol, sulfamethoxazole, and trimethoprim at 232.5 microg L(-1). When plants reached maturity, nine entire plants of each species were separated into components such as roots, leaves, stems, and seedpods where applicable. An analytical method for quantifying pharmaceuticals and personal care products was developed using pressurized liquid extraction and liquid chromatography electrospray ionization mass spectrometry (LC/ESI/MS) in positive and negative ion modes using single ion monitoring. The method detection limits ranged from 3.13 ng g(-1) to 29.78 ng g(-1) with recoveries ranging from 66.83% to 113.62% from plant matrices. All four of the pharmaceuticals were detected in the roots and leaves of the cabbage. The maximum wet weight concentrations of the pharmaceuticals were detected in the root structure of the cabbage plants at 98.87 ng g(-1) carbamazepine, 114.72 ng g(-1) salbutamol, 138.26 ng g(-1) sulfamethoxazole, and 91.33 ng g(-1) trimethoprim. Carbamazepine and salbutamol were detected in the seedpods of the Wisconsin Fast Plants while all four of the pharmaceuticals were detected in the leaf/stem/root of the Wisconsin Fast Plants. Phloroglucinol staining of root cross-sections was used to verify the existence of an intact endodermis, suggesting that pharmaceuticals found in the leaf and seedpods of the plants were transported symplastically. PMID:20096438

  20. Phytoremediation of imazalil and tebuconazole by four emergent wetland plant species in hydroponic medium.

    PubMed

    Lv, Tao; Zhang, Yang; Casas, Mònica E; Carvalho, Pedro N; Arias, Carlos A; Bester, Kai; Brix, Hans

    2016-04-01

    Pollution from pesticide residues in aquatic environments is of increasing concern. Imazalil and tebuconazole, two commonly used systemic pesticides, are water contaminants that can be removed by constructed wetlands. However, the phytoremediation capability of emergent wetland plants for imazalil and tebuconazole, especially the removal mechanisms involved, is poorly understood. This study compared the removal of both pesticides by four commonly used wetland plants, Typha latifolia, Phragmites australis, Iris pseudacorus and Juncus effusus, and aimed to understand the removal mechanisms involved. The plants were individually exposed to an initial concentration of 10 mg/L in hydroponic solution. At the end of the 24-day study period, the tebuconazole removal efficiencies were relatively lower (25%-41%) than those for imazalil (46%-96%) for all plant species studied. The removal of imazalil and tebuconazole fit a first-order kinetics model, with the exception of tebuconazole removal in solutions with I. pseudacorus. Changes in the enantiomeric fraction for imazalil and tebuconazole were detected in plant tissue but not in the hydroponic solutions; thus, the translocation and degradation processes were enantioselective in the plants. At the end of the study period, the accumulation of imazalil and tebuconazole in plant tissue was relatively low and constituted 2.8-14.4% of the total spiked pesticide in each vessel. Therefore, the studied plants were able to not only take up the pesticides but also metabolise them. PMID:26841287

  1. Prebiotics and calcium bioavailability.

    PubMed

    Cashman, Kevin

    2003-03-01

    A prebiotic substance has been defined as a non-digestible food ingredient that beneficially affects the host by selectively stimulating the growth and/or activity of one or a limited number of bacteria in the colon. Therefore, compared to probiotics, which introduce exogenous bacteria into the colonic microflora, a prebiotic aims at stimulating the growth of one or a limited number of the potentially health-promoting indigenous micro-organisms, thus modulating the composition of the natural ecosystem. In recent years, increasing attention has been focussed on the possible beneficial effects of prebiotics, such as enhanced resistance to invading pathogens, improved bowel function, anti-colon cancer properties, lipid lowering action, improved calcium bioavailability, amongst others. The objective of this review is to critically assess the available data on the effects of prebiotics on calcium bioavailability, and place it in the context of human physiology and, when possible, explain the underlying cellular and molecular mechanisms. The review will also try to highlight future areas of research that may help in the evaluation of prebiotics as potential ingredients for functional foods aimed at enhancing calcium bioavailability and protecting against osteoporosis. PMID:12691259

  2. Bioavailability of Cadmium in Inexpensive Jewelry

    PubMed Central

    Miller, Jennifer; Guinn, Daphne; Pearson, Janna

    2011-01-01

    Objectives: We evaluated the bioavailability of Cd in 86 components of 57 jewelry items found to contain high levels of Cd (> 10,000 ppm) by X-ray fluorescence (XRF), using extractions that simulate mouthing or swallowing of jewelry items. Methods: We screened jewelry for Cd content by XRF. Bioavailability was measured in two ways. Items were placed in saline solution at 37°C for 6 hr to simulate exposures from mouthing of jewelry items. Items were placed in dilute hydrochloric acid (HCl) at 37°C for 6–96 hr, simulating the worst-case scenario of a child swallowing a jewelry item. Damaged pieces of selected samples were also extracted by both methods to determine the effect of breaching the outer plating on bioavailability. Total Cd content of all items was determined by atomic absorption. Results: The 6-hr saline extraction yielded as much as 2,200 µg Cd, and 24-hr dilute HCl extraction yielded a maximum of > 20,000 µg Cd. Leaching of Cd in dilute HCl increased linearly over 6–96 hr, indicating potential for increasing harm the longer an item remains in the stomach. Damage to jewelry by breaching the outer plating generally, but not always, increased Cd release. Bioavailability did not correlate directly with Cd content. Conclusions: These results indicate the potential for dangerous Cd exposures to children who wear, mouth, or accidentally swallow high-Cd jewelry items. PMID:21377949

  3. Assessment of a closed greenhouse aquaculture and hydroponic system

    SciTech Connect

    Head, W.D.

    1984-01-01

    Research was conducted to address three objectives: 1) to determine the nitrogen cycling of a closed greenhouse aquaculture and hydroponic system; 2) to determine the energy budget of a closed greenhouse aquaculture and hydroponic system; and 3) to determine which low cost fish diets could be used as a replacement or supplement to commercial diets for Tilapia mossambica. A 6435 liter recirculating aquaculture system was enclosed in a 32.6 m/sup 2/ greenhouse. Water was recirculated through two 416 liter trickling filter towers and three 5.5 m long hydroponic troughs. The aquaculture tank was stocked with a polyculture of channel catfish (Ictalurus punctatus) and tilapia (Tilapia mossambica) and the hydroponic troughs were planted with tomatoes (Lycopersicon esculentum). The fishes were fed a commercial fish diet and the tomatoes were irrigated with the aquaculture water using a modified Nutrient Film Technique. The fish yield was 42.2 kg and the average tomato yield from 24 plants was 4.1 kg/plant. The combined fish and tomato production accounted for 65% of the total nitrogen input. Leaf analyses and visual inspection showed that the tomato plants from the hydroponic troughs were deficient in potassium and magnesium. An energy analysis of the greenhouse and aquaculture-hydroponic system showed that when combining the energy outputs of heat, fish, and tomatoes the energy ratio (energy output/energy input) was similar to literature values for milkfish pond culture. When only the fish production was considered the energy ratio was similar to literature values reported for intensive water recirculating systems.

  4. Growth of sweetpotato cultured in the newly designed hydroponic system for space farming

    NASA Astrophysics Data System (ADS)

    Kitaya, Y.; Hirai, H.; Wei, X.; Islam, A. F. M. S.; Yamamoto, M.

    Life support of crews in long-duration space missions for other planets will be highly dependent on amounts of food, atmospheric O2 and clean water produced by plants. Therefore, the space farming system with scheduling of crop production, obtaining high yields with a rapid turnover rate, converting atmospheric CO2 to O2 and purifying water should be established with employing suitable plant species and cultivars and precisely controlling environmental variables around plants grown at a high density in a limited space. In this study, we developed a new hydroponic method for producing tuberous roots and fresh edible leaves and stems of sweetpotato. In the first experiment, we examined the effects of water contents in the rooting substrate on growth and tuberous root development of sweetpotato. The rooting substrates made with rockwool slabs were inclined in a culture container and absorbed nutrient solution from the lower end of the slabs by capillary action. Tuberous roots developed on the lower surface of the rockwool slabs. The tuberous roots showed better growth and development at locations farther from the water surface on the rockwool slabs, which had lower water content. In the second experiment, three sweetpotato cultivars were cultured in a hydroponic system for five months from June to November under the sun light in Osaka, Japan as a fundamental study for establishing the space farming system. The cultivars employed were ‘Elegant summer’, ‘Kokei-14’ and ‘Beniazuma’. The hydroponic system mainly consisted of culture containers and rockwool slabs. Dry weights of tuberous roots developed in the aerial space between the rockwool slab and the nutrient solution filled at the bottom of the culture container were 0.34, 0.45 and 0.23 kg/plant and dry weights of the top portion (leaves, petioles and stems) were 0.42, 0.29 and 0.61 kg/plant for ‘Elegant summer’, ‘Kokei-14’ and ‘Beniazuma’, respectively. Young stems and leaves as well as

  5. Biocompatibility of sweetpotato and peanut in a hydroponic system

    NASA Technical Reports Server (NTRS)

    Mortley, D. G.; Loretan, P. A.; Hill, W. A.; Bonsi, C. K.; Morris, C. E.; Hall, R.; Sullen, D.

    1998-01-01

    'Georgia Red' peanut (Arachis hypogaea L.) and TU-82-155 sweetpotato [Ipomoea batatas (L.) Lam] were grown in monocultured or intercropped recirculating hydroponic systems in a greenhouse using the nutrient film technique (NFT). The objective was to determine whether growth and subsequent yield would be affected by intercropping. Treatments were sweetpotato monoculture (SP), peanut monoculture (PN), and sweetpotato and peanut grown in separate NFT channels but sharing a common nutrient solution (SP-PN). Greenhouse conditions ranged from 24 to 33 degrees C, 60% to 90% relative humidity (RH), and photosynthetic photon flux (PPF) of 200 to 1700 micromoles m-2 s-1. Sweetpotato cuttings (15 cm long) and 14-day-old seedlings of peanuts were planted into growth channels (0.15 x 0.15 x 1.2 m). Plants were spaced 25 cm apart within and 25 cm apart between growing channels. A modified half-Hoagland solution with a 1 N: 2.4 K ratio was used. Solution pH was maintained between 5.5 and 6.0 for treatments involving SP and 6.4 and 6.7 for PN. Electrical conductivity (EC) ranged between 1100 and 1200 microS cm-1. The number of storage roots per sweetpotato plant was similar for both SP and SP-PN. Storage root fresh and dry mass were 29% and 36% greater, respectively, for plants in the SP-PN treatment than for plants in the SP treatment. The percent dry mass of the storage roots, dry mass of fibrous and pencil roots, and the length-to-diameter ratio of storage roots were similar for SP and SP-PN sweetpotato plants. Likewise, foliage fresh and dry mass and harvest index were not significantly influenced by treatment. Total dry mass was 37% greater for PN than for SP-PN peanut plants, and pod dry mass was 82% higher. Mature and total seed dry mass and fibrous root dry mass were significantly greater for PN than for SP-PN plants. Harvest index (HI) was similar for both treatments. Root length tended to be lower for seedlings grown in the nutrient solution from the SP-PN treatment.

  6. Lead phytoremediation potential of Vetiver grass: a hydroponic study

    NASA Astrophysics Data System (ADS)

    Pachanoor, D. S.; Andra, S. P.; Datta, R.; Sarkar, D.

    2006-05-01

    Lead (Pb) is a toxic heavy metal that is released into the environment from a variety of sources. Sources of Pb contamination in soils can be divided into three broad categories: industrial activities, such as mining and smelting processes, agricultural activities, such as application of insecticide and municipal sewage sludge, and urban activities, such as use of Pb in gasoline, paints, and other materials. Severe Pb contamination of soils may cause a variety of environmental problems, including loss of vegetation, groundwater contamination and Pb toxicity in plants, animals and humans. The use of plants to remove toxic metals from soils (phytoremediation) is fast emerging as an acceptable strategy for cost-effective and environmentally sound remediation of contaminated soils. The objective of this study was to gain insight into the lead uptake potential and biochemical stress response mechanism in vetiver grass (Vetiveria zizanioides L.) upon exposure to Pb in contaminated soils. We investigated the effect of increasing concentrations of Pb on vetiver grass grown in a hydroponic system. Plant response to the addition of phosphate in the presence of Pb was also studied. Biochemical stress response was studied by monitoring the activities of Superoxide dismutase (SOD) and glutathione peroxidase (GPx) enzymes. The results indicated that exposure to Pb in the range of 0 ppm -1200 ppm had no significant negative effects on the growth of vetiver grass. There was no considerable decrease in vetiver biomass, implying the potential of this grass for Pb phytoremediation. The translocation of Pb from the root to the shoot was up to 20%. The SOD activity was in positive correlation with Pb concentrations in the solution, but no such trend was observed with GPx. In systems containing phosphate fertilizer, lead precipitated out immediately, thereby decreasing the soluble concentration of lead, resulting in less availability of Pb to the grass.

  7. [Feasibility of the use of degraded inedible biomass of plants as a nutrient liquid for hydroponic cultivation].

    PubMed

    Guo, S S; Ai, W D; Hou, W H; Shi, W W

    2001-10-01

    Objective. To demonstrate that the recycled liquid, which originated from lettuce inedible biomass degraded by fixed microorganism (correction of microorgannism) and enzyme, can be used as a nutrient solution for lettuce hydroponic cultivation. Method. After biologically degrading the weighted, oven-dried and milled leaves and roots of lettuce in a biological reactor under aerobic condition, the original effluent and its supplemented effluent were used as nutrients for lettuce hydroponic cultivation. Result. The average dried weight (ADW) of lettuce from the original effluent group was approximately half of that from the control group, and the ADW from supplemented effluent group was about equal to that from the control group; some qualities of the lettuce such as a relatively lower content of NO3- from both the original effluent group and the supplemented effluent one improved, and some of those such as a relatively higher content of NO2- dropped. Conclusion. The biologically-degraded effluent was able to be used as nutrient solution for lettuce hydroponic cultivation, although the effects of the inorganic ion-supplemented effluent were much better; the plants of lettuce from the biologically-degraded effluent were safely edible. PMID:11842852

  8. Sludge organics bioavailability

    SciTech Connect

    Eiceman, G.E.; Bellin, C.A.; Ryan, J.A.; O'Connor, G.A.

    1991-01-01

    Concern over the bioavailability of toxic organics that can occur in municipal sludges threatens routine land application of sludge. Available data, however, show that concentrations of priority organics in normal sludges are low. Sludges applied at agronomic rates yield chemical concentrations in soil-sludge mixtures 50 to 100 fold lower. Plant uptake at these pollutant concentrations (and at much higher concentrations) is minimal. Chemicals are either (1) accumulated at extremely low levels (PCBs), (2) possibly accumulated, but then rapidly metabolized within plants to extremely low levels (DEHP), or (3) likely degraded so rapidly in soil that only minor contamination occurs (PCP and 2,4-DNP).

  9. Hydroponic Growth and the Nondestructive Assay for Dinitrogen Fixation 1

    PubMed Central

    Imsande, John; Ralston, Edward J.

    1981-01-01

    Hydroponic growth medium must be well buffered if it is to support sustained plant growth. Although 1.0 millimolar phosphate is commonly used as a buffer for hydroponic growth media, at that concentration it is generally toxic to a soybean plant that derives its nitrogen solely from dinitrogen fixation. On the other hand, we show that 1.0 to 2.0 millimolar 2-(N-morpholino)ethanesulfonic acid, pKa 6.1, has excellent buffering capacity, and it neither interferes with nor contributes nutritionally to soybean plant growth. Furthermore, it neither impedes nodulation nor the assay of dinitrogen fixation. Hence, soybean plants grown hydroponically on a medium supplemented with 1.0 to 2.0 millimolar 2-(N-morpholino)ethanesulfonic acid and 0.1 millimolar phosphate achieve an excellent rate of growth and, in the absence of added fixed nitrogen, attain a very high rate of dinitrogen fixation. Combining the concept of hydroponic growth and the sensitive acetylene reduction technique, we have devised a simple, rapid, reproducible assay procedure whereby the rate of dinitrogen fixation by individual plants can be measured throughout the lifetime of those plants. The rate of dinitrogen fixation as measured by the nondestructive acetylene reduction procedure is shown to be approximately equal to the rate of total plant nitrogen accumulation as measured by Kjeldahl analysis. Because of the simplicity of the procedure, one investigator can readily assay 50 plants individually per day. PMID:16662112

  10. Enhanced solubility and bioavailability of flurbiprofen by cycloamylose.

    PubMed

    Baek, Hyung Hee; Kwon, So Young; Rho, Shin-Joung; Lee, Won Seok; Yang, Ho-Joon; Hah, Jung-Mi; Choi, Han-Gon; Kim, Yong-Ro; Yong, Chul Soon

    2011-03-01

    The effect of cycloamylose on the aqueous solubility of flurbiprofen was investigated. To improve the solubility and bioavailability of flurbiprofen (poor water solubility), a solid dispersion was spray dried with a solution of flurbiprofen and cycloamylose at a weight ratio of 1:1. The physicochemical properties of solid dispersions were investigated using SEM, DSC, and X-ray diffraction. The dissolution and bioavailability in rats were evaluated compared with a commercial product. Cycloamylose increased solubility of flurbiprofen approximately 12-fold and dissolution of it by 2-fold. Flurbiprofen was present in an unchanged crystalline state, and cycloamylose was a solubilizing agent for flurbiprofen in this solid dispersion. Furthermore, the dispersion gave higher AUC and C(max) values compared with the commercial product, indicating that it improved the oral bioavailability of flurbiprofen in rats. Thus, the solid dispersion may be useful to deliver flurbiprofen with enhanced bioavailability without changes in crystalline structure. PMID:21547670

  11. Micronutrient bioavailability research priorities.

    PubMed

    Casgrain, Amélie; Collings, Rachel; Harvey, Linda J; Boza, Julio J; Fairweather-Tait, Susan J

    2010-05-01

    A micronutrient bioavailability workshop, which involved international experts and members of the scientific community and the food industry, with interactive breakout sessions based on synectics principles, was organized by the International Life Sciences Institute Europe Addition of Nutrients to Food Task Force and the European Commission Network of Excellence European Micronutrient Recommendations Aligned. After presentations by experts, a series of "challenge statements" was discussed. The aim was to address topical issues, in particular those that linked bioavailability with the derivation of micronutrient requirements and dietary recommendations, to identify gaps in knowledge and to consider research priorities. Several generic research priorities were identified, including improving the quality of dietary surveys/food composition tables, the need for more metabolic studies that use stable isotopes and high-quality longer-term interventions, and the development of multifactorial mathematical models. Among the common recurrent factors identified as important were polymorphisms/genotype, consideration of the whole diet, chemical form of the micronutrient, and the determination of physiologic requirements. The involvement of all participants in the structured discussions ensured a broad overview of current knowledge, state-of-the-art research, and consideration of priorities for future research. PMID:20200267

  12. [Yeast irrigation enhances the nutritional content in hydroponic green maize fodder].

    PubMed

    Bedolla-Torres, Martha H; Palacios Espinosa, Alejandro; Palacios, Oskar A; Choix, Francisco J; Ascencio Valle, Felipe de Jesús; López Aguilar, David R; Espinoza Villavicencio, José Luis; de Luna de la Peña, Rafael; Guillen Trujillo, Ariel; Avila Serrano, Narciso Y; Ortega Pérez, Ricardo

    2015-01-01

    The objective of this study was to evaluate the effect of irrigation with yeasts (Debaryomyces hansenii var. Fabry, Yarowia lipolytica YIBCS002, Yarowia lipolytica var. BCS and Candida pseudointermedia) on the final nutritional content of hydroponic green maize fodder (Zea Zea mays L.), applied at different fodder growth stages (1. seed-seedling stage, 2. seedling-plant 20cm, 3. during all the culture). Irrespective of the fodder growth stages at which they were applied, all yeasts tested enhanced the content of raw protein, lipids, ash, moisture and energy. The percentage of electrolytes (Na, K, Cl, sulphates, Ca and Mg) showed different responses depending on the kind of yeast applied; D. hansenii exhibited the highest increment in all electrolytes, except for phosphorous. We conclude that the addition of yeasts belonging to the genera Debaryomyces, Candida and Yarowia to the irrigation solution of hydroponic systems enhances the nutrient content of green fodder. This kind of irrigation can be applied to generate high commercial value cultures in limited spaces. PMID:26364185

  13. The influence of different hydroponic conditions on thorium uptake by Brassica juncea var. foliosa.

    PubMed

    Wang, Dingna; Zhou, Sai; Liu, Li; Du, Liang; Wang, Jianmei; Huang, Zhenling; Ma, Lijian; Ding, Songdong; Zhang, Dong; Wang, Ruibing; Jin, Yongdong; Xia, Chuanqin

    2015-05-01

    The effects of different hydroponic conditions (such as concentration of thorium (Th), pH, carbonate, phosphate, organic acids, and cations) on thorium uptake by Brassica juncea var. foliosa were evaluated. The results showed that acidic cultivation solutions enhanced thorium accumulation in the plants. Phosphate and carbonate inhibited thorium accumulation in plants, possibly due to the formation of Th(HPO4)(2+), Th(HPO4)2, or Th(OH)3CO3 (-) with Th(4+), which was disadvantageous for thorium uptake in the plants. Organic aids (citric acid, oxalic acid, lactic acid) inhibited thorium accumulation in roots and increased thorium content in the shoots, which suggested that the thorium-organic complexes did not remain in the roots and were beneficial for thorium transfer from the roots to the shoots. Among three cations (such as calcium ion (Ca(2+)), ferrous ion (Fe(2+)), and zinc ion (Zn(2+))) in hydroponic media, Zn(2+) had no significant influence on thorium accumulation in the roots, Fe(2+) inhibited thorium accumulation in the roots, and Ca(2+) was found to facilitate thorium accumulation in the roots to a certain extent. This research will help to further understand the mechanism of thorium uptake in plants. PMID:25475618

  14. Yield and gas exchange ability of sweetpotato plants cultured in a hydroponic system

    NASA Astrophysics Data System (ADS)

    Kitaya, Y.; Hirai, H.; Saiful Islam, A. F. M.; Yamamoto, M.

    Life support of crews in space is greatly dependent on the amounts of food atmospheric O 2 and clean water produced by plants Therefore the space farming systems with scheduling of crop production obtaining high yields with a rapid turnover rate converting atmospheric CO 2 to O 2 and purifying water should be established with employing suitable plant species and varieties and precisely controlling environmental variables around plants grown at a high density in a limited space In this study three sweetpotato varieties were cultured in a newly developed hydroponic system and the yield the photosynthetic rate and the transpiration rate were compared on the earth as a fundamental study for establishing the space farming systems The varieties were Elegant summer Koukei 14 and Beniazuma The hydroponic system mainly consisted of water channels and rockwool boards A growing space for roots was made between the rockwool board and nutrient solution in the water channel Storage roots were developed on the lower surface of the rockwool plates Fresh weights of the storage roots were 1 6 1 2 and 0 6 kg plant for Koukei 14 Elegant summer and Beniazuma respectively grown for five months from June to October under the sun light in Osaka Japan Koukei 14 and Elegant summer produced greater total phytomass than Beniazuma There were positive correlations among the total phytomass the net photosynthetic rate and the transpiration rate Young stems and leaves as well as storage roots of Elegant summer are edible Therefore Elegant-summer

  15. Fluoride bioaccumulation by hydroponic cultures of camellia (Camellia japonica spp.) and sugar cane (Saccharum officinarum spp.).

    PubMed

    Camarena-Rangel, Nancy; Rojas Velázquez, Angel Natanael; Santos-Díaz, María del Socorro

    2015-10-01

    The ability of hydroponic cultures of camellia and sugar cane adult plants to remove fluoride was investigated. Plants were grown in a 50% Steiner nutrient solution. After an adaptation period to hydroponic conditions, plants were exposed to different fluoride concentrations (0, 2.5, 5 and 10 mg L(-1)). Fluoride concentration in the culture medium and in tissues was measured. In sugar cane, fluoride was mainly located in roots, with 86% of it absorbed and 14% adsorbed. Sugar cane plants removed 1000-1200 mg fluoride kg(-1) dry weight. In camellia plants the highest fluoride concentration was found in leaf. Roots accumulated fluoride mainly through absorption, which was 2-5 times higher than adsorption. At the end of the experiment, fluoride accumulation in camellia plants was 1000-1400 mgk g(-1) dry weight. Estimated concentration factors revealed that fluoride bioaccumulation is 74-221-fold in camellia plants and 100-500-fold in sugar cane plants. Thus, the latter appear as a suitable candidate for removing fluoride from water due to their bioaccumulation capacity and vigorous growth rate; therefore, sugar cane might be used for phytoremediation. PMID:25930125

  16. Fiber optic spectrophotometry monitoring of plant nutrient deficiency under hydroponic culture conditions

    NASA Astrophysics Data System (ADS)

    Liew, Oi Wah; Boey, William S. L.; Asundi, Anand K.; Chen, Jun-Wei; He, Duo-Min

    1999-05-01

    In this paper, fiber optic spectrophotometry (FOSpectr) was adapted to provide early detection of plant nutrient deficiency by measuring leaf spectral reflectance variation resulting from nutrient stress. Leaf reflectance data were obtained form a local vegetable crop, Brassica chinensis var parachinensis (Bailey), grown in nitrate-nitrogen (N)- and calcium (Ca)- deficient hydroponics nutrient solution. FOSpectr analysis showed significant differences in leaf reflectance within the first four days after subjecting plants to nutrient-deficient media. Recovery of the nutrient-stressed plants could also be detected after transferring them back to complete nutrient solution. In contrast to FOSpectr, plant response to nitrogen and calcium deficiency in terms of reduced growth and tissue elemental levels was slower and less pronounced. Thus, this study demonstrated the feasibility of using FOSpectr methodology as a non-destructive alternative to augment current methods of plant nutrient analysis.

  17. Microbial reporters of metal bioavailability

    PubMed Central

    Magrisso, Sagi; Erel, Yigal; Belkin, Shimshon

    2008-01-01

    Summary When attempting to assess the extent and the implications of environmental pollution, it is often essential to quantify not only the total concentration of the studied contaminant but also its bioavailable fraction: higher bioavailability, often correlated with increased mobility, signifies enhanced risk but may also facilitate bioremediation. Genetically engineered microorganisms, tailored to respond by a quantifiable signal to the presence of the target chemical(s), may serve as powerful tools for bioavailability assessment. This review summarizes the current knowledge on such microbial bioreporters designed to assay metal bioavailability. Numerous bacterial metal‐sensor strains have been developed over the past 15 years, displaying very high detection sensitivities for a broad spectrum of environmentally significant metal targets. These constructs are based on the use of a relatively small number of gene promoters as the sensing elements, and an even smaller selection of molecular reporter systems; they comprise a potentially useful panel of tools for simple and cost‐effective determination of the bioavailability of heavy metals in the environment, and for the quantification of the non‐bioavailable fraction of the pollutant. In spite of their inherent advantages, however, these tools have not yet been put to actual use in the evaluation of metal bioavailability in a real environmental remediation scheme. For this to happen, acceptance by regulatory authorities is essential, as is a standardization of assay conditions. PMID:21261850

  18. Use of biologically reclaimed minerals for continuous hydroponic potato production in a CELSS

    NASA Astrophysics Data System (ADS)

    Mackowiak, C. L.; Wheeler, R. M.; Stutte, G. W.; Yorio, N. C.; Sager, J. C.

    1997-01-01

    Plant-derived nutrients were successfully recycled in a Controlled Ecological Life Support System (CELSS) using biological methods. The majority of the essential nutrients were recovered by microbiologically treating the plant biomass in an aerobic bioreactor. Liquid effluent containing the nutrients was then returned to the biomass production component via a recirculating hydroponic system. Potato (Solanum tuberosum L.) cv. Norland plants were grown on those nutrients in either a batch production mode (same age plants on a nutrient solution) or a staggered production mode (4 different ages of plants on a nutrient solution). The study continued over a period of 418 days, within NASA Breadboard Project's Biomass Production Chamber at the Kennedy Space Center. During this period, four consecutive batch cycles (104-day harvests) and 13 consecutive staggered cycles (26-day harvests) were completed using reclaimed minerals and compared to plants grown with standard nutrient solutions. All nutrient solutions were continually recirculated during the entire 418 day study. In general, tuber yields with reclaimed minerals were within 10% of control solutions. Contaminants, such as sodium and recalcitrant organics tended to increase over time in solutions containing reclaimed minerals, however tuber composition was comparable to tubers grown in the control solutions.

  19. Use of biologically reclaimed minerals for continuous hydroponic potato production in a CELSS.

    PubMed

    Mackowiak, C L; Wheeler, R M; Stutte, G W; Yorio, N C; Sager, J C

    1997-01-01

    Plant-derived nutrients were successfully recycled in a Controlled Ecological Life Support System (CELSS) using biological methods. The majority of the essential nutrients were recovered by microbiologically treating the plant biomass in an aerobic bioreactor. Liquid effluent containing the nutrients was then returned to the biomass production component via a recirculating hydroponic system. Potato (Solanum tuberosum L.) cv. Norland plants were grown on those nutrients in either a batch production mode (same age plants on a nutrient solution) or a staggered production mode (4 different ages of plants on a nutrient solution). The study continued over a period of 418 days, within NASA Breadboard Project's Biomass Production Chamber at the Kennedy Space Center. During this period, four consecutive batch cycles (104-day harvests) and 13 consecutive staggered cycles (26-day harvests) were completed using reclaimed minerals and compared to plants grown with standard nutrient solutions. All nutrient solutions were continually recirculated during the entire 418 day study. In general, tuber yields with reclaimed minerals were within 10% of control solutions. Contaminants, such as sodium and recalcitrant organics tended to increase over time in solutions containing reclaimed minerals, however tuber composition was comparable to tubers grown in the control solutions. PMID:11542555

  20. Growing root, tuber and nut crops hydroponically for CELSS

    NASA Astrophysics Data System (ADS)

    Hill, W. A.; Mortley, D. G.; Mackowiak, C. L.; Loretan, P. A.; Tibbitts, T. W.; Wheeler, R. M.; Bonsi, C. K.; Morris, C. E.

    1992-07-01

    Among the crops selected by the National Aeronautics and Space Administration for growth in controlled ecological life support systems are four that have subsurface edible parts - potatoes, sweet potatoes, sugar beets and peanuts. These crops have been produced in open and closed (recirculating), solid media and liquid, hydroponic systems. Fluorescent, fluorescent plus incandescent and high pressure sodium plus metal halide lamps have proven to be effective light sources. Continuous light with 16°C and 28/22°C (day/night) temperatures have produced highest yields for potato and sweet potato, respectively. Dry weight yields of up to 4685, 2541, 1151 and 207 g m-e for potatoes, sweet potatoes, sugar beets and peanuts, respectively, have been produced in controlled environment hydroponic systems.

  1. Growing root, tuber and nut crops hydroponically for CELSS.

    PubMed

    Hill, W A; Mortley, D G; Mackowiak, C L; Loretan, P A; Tibbitts, T W; Wheeler, R M; Bonsi, C K; Morris, C E

    1992-01-01

    Among the crops selected by the National Aeronautics and Space Administration for growth in controlled ecological life support systems are four that have subsurface edible parts -- potatoes, sweet potatoes, sugar beets and peanuts. These crops have been produced in open and closed (recirculating), solid media and liquid, hydroponic systems. Fluorescent , fluorescent plus incandescent and high pressure sodium plus metal halide lamps have proven to be effective light sources. Continuous light with 16 degrees C and 28/22 degrees C (day/night) temperatures have produced highest yields for potato and sweet potato, respectively. Dry weight yields of up to 4685, 2541, 1151 and 207 g m-2 for for potatoes, sweet potatoes, sugar beets and peanuts, respectively, have been produced in controlled environment hydroponic systems. PMID:11537058

  2. Growing root, tuber and nut crops hydroponically for CELSS

    NASA Technical Reports Server (NTRS)

    Hill, W. A.; Mortley, D. G.; Loretan, P. A.; Bonsi, C. K.; Morris, C. E.; Mackowiak, C. L.; Wheeler, R. M.; Tibbitts, T. W.

    1992-01-01

    Among the crops selected by NASA for growth in controlled ecological life-support systems are four that have subsurface edible parts: potatoes, sweet potatoes, sugar beets and peanuts. These crops can be produced in open and closed (recirculating), solid media and liquid, hydroponic systems. Fluorescent, fluorescent plus incandescent, and high-pressure sodium-plus-metal-halide lamps have proven to be effective light sources. Continuous light with 16-C and 28/22-C (day/night) temperatures produce highest yields for potato and sweet potato, respectively. Dry weight yields of up to 4685, 2541, 1151 and 207 g/sq m for potatoes, sweet potatoes, sugar beets and peanuts, respectively, are produced in controlled environment hydroponic systems.

  3. Root-Contact/Pressure-Plate Assembly For Hydroponic System

    NASA Technical Reports Server (NTRS)

    Morris, Carlton E.; Loretan, Philip A.; Bonsi, Conrad K.; Hill, Walter A.

    1994-01-01

    Hydroponic system includes growth channels equipped with rootcontact/pressure-plate assemblies. Pump and associated plumbing circulate nutrient liquid from reservoir, along bottom of growth channels, and back to reservoir. Root-contact/pressure-plate assembly in each growth channel stimulates growth of roots by applying mild contact pressure. Flat plate and plate connectors, together constitute pressure plate, free to move upward to accommodate growth of roots. System used for growing sweetpotatoes and possibly other tuber and root crops.

  4. Bioavailability: implications for science/cleanup policy

    SciTech Connect

    Denit, Jeffery; Planicka, J. Gregory

    1998-12-01

    This paper examines the role of bioavailability in risk assessment and cleanup decisions. Bioavailability refers to how chemicals ''behave'' and their ''availability'' to interact with living organisms. Bioavailability has significant implications for exposure risks, cleanup goals, and site costs. Risk to human health and the environment is directly tied to the bioavailability of the chemicals of concern.

  5. Suitability of Gray Water for Hydroponic Crop Production Following Biological and Physical Chemical and Biological Subsystems

    NASA Technical Reports Server (NTRS)

    Bubenheim, David L.; Harper, Lynn D.; Wignarajah, Kanapathipillai; Greene, Catherine

    1994-01-01

    The water present in waste streams from a human habitat must be recycled in Controlled Ecological Life Support Systems (CELSS) to limit resupply needs and attain self-sufficiency. Plants play an important role in providing food, regenerating air, and producing purified water via transpiration. However, we have shown that the surfactants present in hygiene waste water have acute toxic effects on plant growth (Bubenheim et al. 1994; Greene et al., 1994). These phytotoxic affects can be mitigated by allowing the microbial population on the root surface to degrade the surfactant, however, a significant suppression (several days) in crop performance is experienced prior to reaching sub-toxic surfactant levels and plant recovery. An effective alternative is to stabilize the microbial population responsible for degradation of the surfactant on an aerobic bioreactor and process the waste water prior to utilization in the hydroponic solution (Wisniewski and Bubenheim, 1993). A sensitive bioassay indicates that the surfactant phytotoxicity is suppressed by more than 90% within 5 hours of introduction of the gray water to the bioreactor; processing for more than 12 hours degrades more than 99% of the phytotoxin. Vapor Compression Distillation (VCD) is a physical / chemical method for water purification which employees sequential distillation steps to separate water from solids and to volatilize contaminants. The solids from the waste water are concentrated in a brine and the pure product water (70 - 90% of the total waste water volume depending on operating conditions) retains non of the phytotoxic effects. Results of the bioassay were used to guide evaluations of the suitability of recovered gray water following biological and VCD processing for hydroponic lettuce production in controlled environments. Lettuce crops were grown for 28 days with 100% of the input water supplied with recovered water from the biological processor or VCD. When compared with the growth of plants

  6. A Reliable Wireless Control System for Tomato Hydroponics.

    PubMed

    Ibayashi, Hirofumi; Kaneda, Yukimasa; Imahara, Jungo; Oishi, Naoki; Kuroda, Masahiro; Mineno, Hiroshi

    2016-01-01

    Agricultural systems using advanced information and communication (ICT) technology can produce high-quality crops in a stable environment while decreasing the need for manual labor. The system collects a wide variety of environmental data and provides the precise cultivation control needed to produce high value-added crops; however, there are the problems of packet transmission errors in wireless sensor networks or system failure due to having the equipment in a hot and humid environment. In this paper, we propose a reliable wireless control system for hydroponic tomato cultivation using the 400 MHz wireless band and the IEEE 802.15.6 standard. The 400 MHz band, which is lower than the 2.4 GHz band, has good obstacle diffraction, and zero-data-loss communication is realized using the guaranteed time-slot method supported by the IEEE 802.15.6 standard. In addition, this system has fault tolerance and a self-healing function to recover from faults such as packet transmission failures due to deterioration of the wireless communication quality. In our basic experiments, the 400 MHz band wireless communication was not affected by the plants' growth, and the packet error rate was less than that of the 2.4 GHz band. In summary, we achieved a real-time hydroponic liquid supply control with no data loss by applying a 400 MHz band WSN to hydroponic tomato cultivation. PMID:27164105

  7. A Reliable Wireless Control System for Tomato Hydroponics

    PubMed Central

    Ibayashi, Hirofumi; Kaneda, Yukimasa; Imahara, Jungo; Oishi, Naoki; Kuroda, Masahiro; Mineno, Hiroshi

    2016-01-01

    Agricultural systems using advanced information and communication (ICT) technology can produce high-quality crops in a stable environment while decreasing the need for manual labor. The system collects a wide variety of environmental data and provides the precise cultivation control needed to produce high value-added crops; however, there are the problems of packet transmission errors in wireless sensor networks or system failure due to having the equipment in a hot and humid environment. In this paper, we propose a reliable wireless control system for hydroponic tomato cultivation using the 400 MHz wireless band and the IEEE 802.15.6 standard. The 400 MHz band, which is lower than the 2.4 GHz band, has good obstacle diffraction, and zero-data-loss communication is realized using the guaranteed time-slot method supported by the IEEE 802.15.6 standard. In addition, this system has fault tolerance and a self-healing function to recover from faults such as packet transmission failures due to deterioration of the wireless communication quality. In our basic experiments, the 400 MHz band wireless communication was not affected by the plants’ growth, and the packet error rate was less than that of the 2.4 GHz band. In summary, we achieved a real-time hydroponic liquid supply control with no data loss by applying a 400 MHz band WSN to hydroponic tomato cultivation. PMID:27164105

  8. Plant-uptake of uranium: Hydroponic and soil system studies

    USGS Publications Warehouse

    Ramaswami, A.; Carr, P.; Burkhardt, M.

    2001-01-01

    Limited information is available on screening and selection of terrestrial plants for uptake and translocation of uranium from soil. This article evaluates the removal of uranium from water and soil by selected plants, comparing plant performance in hydroponic systems with that in two soil systems (a sandy-loam soil and an organic-rich soil). Plants selected for this study were Sunflower (Helianthus giganteus), Spring Vetch (Vicia sativa), Hairy Vetch (Vicia villosa), Juniper (Juniperus monosperma), Indian Mustard (Brassica juncea), and Bush Bean (Phaseolus nanus). Plant performance was evaluated both in terms of the percent uranium extracted from the three systems, as well as the biological absorption coefficient (BAC) that normalized uranium uptake to plant biomass. Study results indicate that uranium extraction efficiency decreased sharply across hydroponic, sandy and organic soil systems, indicating that soil organic matter sequestered uranium, rendering it largely unavailable for plant uptake. These results indicate that site-specific soils must be used to screen plants for uranium extraction capability; plant behavior in hydroponic systems does not correlate well with that in soil systems. One plant species, Juniper, exhibited consistent uranium extraction efficiencies and BACs in both sandy and organic soils, suggesting unique uranium extraction capabilities.

  9. A hydroponic system for microgravity plant experiments.

    PubMed

    Wright, B D; Bausch, W C; Knott, W M

    1988-01-01

    The construction of a permanently manned space station will provide the opportunity to grow plants for weeks or months in orbit for experiments or food production. With this opportunity comes the need for a method to provide plants with a continuous supply of water and nutrients in microgravity. The Capillary Effect Root Environment System (CERES) uses capillary forces to maintain control of circulating plant nutrient solution in the weightless environment of an orbiting spacecraft. The nutrient solution is maintained at a pressure slightly less than the ambient air pressure while it flows on one side of a porous membrane. The root, on the other side of the membrane, is surrounded by a thin film of nutrient solution where it contacts the moist surface of the membrane. The root is provided with water, nutrients and air simultaneously. Air bubbles in the nutrient solution are removed using a hydrophobic/hydrophilic membrane system. A model scaled to the size necessary for flight hardware to test CERES in the space shuttle was constructed. PMID:11539001

  10. A hydroponic system for microgravity plant experiments

    NASA Technical Reports Server (NTRS)

    Wright, B. D.; Bausch, W. C.; Knott, W. M.

    1988-01-01

    The construction of a permanently manned space station will provide the opportunity to grow plants for weeks or months in orbit for experiments or food production. With this opportunity comes the need for a method to provide plants with a continuous supply of water and nutrients in microgravity. The Capillary Effect Root Environment System (CERES) uses capillary forces to maintain control of circulating plant nutrient solution in the weightless environment of an orbiting spacecraft. The nutrient solution is maintained at a pressure slightly less than the ambient air pressure while it flows on one side of a porous membrane. The root, on the other side of the membrane, is surrounded by a thin film of nutrient solution where it contacts the moist surface of the membrane. The root is provided with water, nutrients and air simultaneously. Air bubbles in the nutrient solution are removed using a hydrophobic/hydrophilic membrane system. A model scaled to the size necessary for flight hardware to test CERES in the space shuttle was constructed.

  11. Hartig' net formation of Tricholoma vaccinum-spruce ectomycorrhiza in hydroponic cultures.

    PubMed

    Henke, Catarina; Jung, Elke-Martina; Kothe, Erika

    2015-12-01

    For re-forestation of metal-contaminated land, ectomycorrhizal trees may provide a solution. Hence, the study of the interaction is necessary to allow for comprehensive understanding of the mutually symbiotic features. On a structural level, hyphal mantle and the Hartig' net formed in the root apoplast are essential for plant protection and mycorrhizal functioning. As a model, we used the basidiomycete Tricholoma vaccinum and its host spruce (Picea abies). Using an optimized hydroponic cultivation system, both features could be visualized and lower stress response of the tree was obtained in non-challenged cultivation. Larger spaces in the apoplasts could be shown with high statistical significance. The easy accessibility will allow to address metal stress or molecular responses in both partners. Additionally, the proposed cultivation system will enable for other experimental applications like addressing flooding, biological interactions with helper bacteria, chemical signaling, or other biotic or abiotic challenges relevant in the natural habitat. PMID:25791268

  12. Bioavailability of platinum emitted from automobile exhaust.

    PubMed

    Artelt, S; Kock, H; Nachtigall, D; Heinrich, U

    1998-08-01

    A model substance was used which is similar in respect to platinum content of exhaust particles emitted from a three-way-catalytic converter equipped engine. The bioavailability of platinum from such exhaust particles and the kind of platinum species formed in vivo were assessed. An in vitro solubility test showed a solubility of approximately 10 percent of platinum content of the model substance in physiological sodium chloride solution. Two short-term animal studies (8 days) were performed. In all examined rat tissues and body fluids platinum could be detected. In addition, the contribution of the overall bioavailability caused by swallowing a certain amount of the intratracheally applied platinum was evaluated by oral application. It was very low. An analytical method was developed to determine platinum species. Synthetic samples (matrix with a platinum standard solution) were analysed. In rat bronchoalveolar lavage spiked with a platinum standard solution only low molecular complexed platinum was found whereas in rat blood plasma all platinum was bound to proteins. In ongoing studies, the model substance is being tested in a three month rat inhalation study. PMID:9820662

  13. Recycle of Inorganic Nutrients for Hydroponic Crop Production Following Incineration of Inedible Biomass

    NASA Technical Reports Server (NTRS)

    Bubenheim, David L.; Wignarajah, Kanapathipillai; Kliss, Mark H. (Technical Monitor)

    1996-01-01

    Recovery of resources from waste streams is essential for future implementation and reliance on a regenerative life support system. The major waste streams of concern are from human activities and plant wastes. Carbon, water and inorganics are the primary desired raw materials of interest. The goal of resource recovery is maintenance of product quality to insure support of reliable and predictable levels of life support function performance by the crop plant component. Further, these systems must be maintained over extended periods of time, requiring maintenance of nutrient solutions to avoid toxicity and deficiencies. Today, reagent grade nutrients are used to make nutrient solutions for hydroponic culture and these solutions are frequently changed during the life cycle or sometimes managed for only one crop life cycle. The focus of this study was to determine the suitability of the ash product following incineration of inedible biomass as a source of inorganic nutrients for hydroponic crop production. Inedible wheat biomass was incinerated and ash quality characterized. The incinerator ash was dissolved in adequate nitric acid to establish a consistent nitrogen concentration in all nutrient solution treatments. Four experimental nutrient treatments were included: control, ash only, ash supplemented to match control, and ash only quality formulated with reagent grade chemicals. When nutrient solutions are formulated using only ash following-incineration of inedible biomass, a balance in solution is established representing elemental retention following incineration and nutrient proportions present in the original biomass. The resulting solution is not identical to the control. This imbalance resulted in suppression of crop growth. When the ash is supplemented with nutrients to establish the same balance as in the control, growth is identical to the control. The ash appears to carry no phytotoxic materials. Growth in solution formulated with reagent grade chemicals

  14. Response of graywater recycling systems based on hydroponic plant growth to three classes of surfactants

    NASA Technical Reports Server (NTRS)

    Garland, J. L.; Levine, L. H.; Yorio, N. C.; Hummerick, M. E.

    2004-01-01

    Anionic (sodium laureth sulfate, SLES), amphoteric (cocamidopropyl betaine, CAPB) and nonionic (alcohol polyethoxylate, AE) surfactants were added to separate nutrient film technique (NFT) hydroponic systems containing dwarf wheat (Triticum aestivum cv. USU Apogee) in a series of 21 day trials. Surfactant was added either in a (1). temporally dynamic mode (1-3 g surfactant m(-2) growing area d(-1)) as effected by automatic addition of a 300 ppm surfactant solution to meet plant water demand, or (2). continuous mode (2 g surfactant m(-2) growing area d(-1)) as effected by slow addition (10 mLh(-1)) of a 2000 ppm surfactant solution beginning at 4d after planting. SLES showed rapid primary degradation in both experiments, with no accumulation 24 h after initial addition. CAPB and AE were degraded less rapidly, with 30-50% remaining 24 h after initial addition, but CAPB and AE levels were below detection limit for the remainder of the study. No reductions in vegetative growth of wheat were observed in response to SLES, but biomass was reduced 20-25% with CAPB and AE. Microbial communities associated with both the plant roots and wetted hardware surfaces actively degraded the surfactants, as determined by monitoring surfactant levels following pulse additions at day 20 (with plants) and day 21 (after plant removal). In order to test whether the biofilm communities could ameliorate phytotoxicity by providing a microbial community acclimated for CAPB and AE decay, the continuous exposure systems were planted with wheat seeds after crop removal at day 21. Acclimation resulted in faster primary degradation (>90% within 24h) and reduced phytotoxicity. Overall, the studies indicate that relatively small areas (3-5m(2)) of hydroponic plant systems can process per capita production of mixed surfactants (5-10 g x person(-1)d(-1)) with minimal effects on plant growth.

  15. Response of graywater recycling systems based on hydroponic plant growth to three classes of surfactants.

    PubMed

    Garland, J L; Levine, L H; Yorio, N C; Hummerick, M E

    2004-04-01

    Anionic (sodium laureth sulfate, SLES), amphoteric (cocamidopropyl betaine, CAPB) and nonionic (alcohol polyethoxylate, AE) surfactants were added to separate nutrient film technique (NFT) hydroponic systems containing dwarf wheat (Triticum aestivum cv. USU Apogee) in a series of 21 day trials. Surfactant was added either in a (1). temporally dynamic mode (1-3 g surfactant m(-2) growing area d(-1)) as effected by automatic addition of a 300 ppm surfactant solution to meet plant water demand, or (2). continuous mode (2 g surfactant m(-2) growing area d(-1)) as effected by slow addition (10 mLh(-1)) of a 2000 ppm surfactant solution beginning at 4d after planting. SLES showed rapid primary degradation in both experiments, with no accumulation 24 h after initial addition. CAPB and AE were degraded less rapidly, with 30-50% remaining 24 h after initial addition, but CAPB and AE levels were below detection limit for the remainder of the study. No reductions in vegetative growth of wheat were observed in response to SLES, but biomass was reduced 20-25% with CAPB and AE. Microbial communities associated with both the plant roots and wetted hardware surfaces actively degraded the surfactants, as determined by monitoring surfactant levels following pulse additions at day 20 (with plants) and day 21 (after plant removal). In order to test whether the biofilm communities could ameliorate phytotoxicity by providing a microbial community acclimated for CAPB and AE decay, the continuous exposure systems were planted with wheat seeds after crop removal at day 21. Acclimation resulted in faster primary degradation (>90% within 24h) and reduced phytotoxicity. Overall, the studies indicate that relatively small areas (3-5m(2)) of hydroponic plant systems can process per capita production of mixed surfactants (5-10 g x person(-1)d(-1)) with minimal effects on plant growth. PMID:15087176

  16. Detoxification of phytotoxic compounds by TiO2 photocatalysis in a recycling hydroponic cultivation system of asparagus.

    PubMed

    Sunada, Kayano; Ding, Xin Geng; Utami, Melia Sandya; Kawashima, Yoko; Miyama, Yoko; Hashimoto, Kazuhito

    2008-06-25

    TiO 2 photocatalytic decomposition and detoxification of phytotoxic compounds released by the roots of asparagus ( Asparagus officinalis L.) were investigated from the viewpoint of conservation-oriented cultivation. The phytotoxically active fraction was extracted either from dried asparagus roots or from the recycled nutrient solution of an asparagus hydroponic cultivation system. We found that the phytotoxic activity gradually decreased in the fraction with TiO 2 powder under irradiation with ultraviolet (UV) light at an intensity of 1.0 mW/cm (2). The growth of asparagus plants under actual cultivation conditions was also investigated by comparing asparagus grown in a hydroponic system where recycled waste nutrient solution was photocatalytically treated with solar light and a system with untreated recycled waste nutrient solution. The results showed, as measured by growth indices such as stem length and stem thickness, that asparagus growth in the photocatalytically treated system was superior to the untreated one. Furthermore, the yield of asparagus spears was 1.6-fold greater in the photocatalytically treated system, demonstrating the detoxification effect on the phytotoxic compounds and also the killing effect on pathogenic microorganisms. PMID:18500814

  17. Polymeric microcontainers improve oral bioavailability of furosemide.

    PubMed

    Nielsen, Line Hagner; Melero, Ana; Keller, Stephan Sylvest; Jacobsen, Jette; Garrigues, Teresa; Rades, Thomas; Müllertz, Anette; Boisen, Anja

    2016-05-17

    Microcontainers with an inner diameter of 223μm are fabricated using the polymer SU-8, and evaluated in vitro, in situ and in vivo for their application as an advanced oral drug delivery system for the poorly water soluble drug furosemide. An amorphous sodium salt of furosemide (ASSF) is filled into the microcontainers followed by applying a lid using Eudragit L100. It is possible to control the drug release in vitro, and in vitro absorption studies show that the microcontainers are not a hindrance for absorption of ASSF. In situ perfusion studies in rats are performed with ASSF-filled microcontainers coated with Eudragit and compared to a furosemide solution. The absorption rate constant of ASSF confined in microcontainers is found to be significantly different from the solution, and by light microscopy, it is observed that the microcontainers are engulfed by the intestinal mucus. An oral bioavailability study in rats is performed with ASSF confined in microcontainers coated with Eudragit and a control group with ASSF in Eudragit-coated capsules. A relative bioavailability of 220% for the ASSF in microcontainers compared to ASSF in capsules is found. These studies indicate that the microcontainers could serve as a promising oral drug delivery system. PMID:27033999

  18. Soybean cultivar selection for Bioregenerative Life Support Systems (BLSSs) - Hydroponic cultivation

    NASA Astrophysics Data System (ADS)

    Paradiso, R.; Buonomo, R.; De Micco, V.; Aronne, G.; Palermo, M.; Barbieri, G.; De Pascale, S.

    2012-12-01

    Four soybean cultivars ('Atlantic', 'Cresir', 'Pr91m10' and 'Regir'), selected through a theoretical procedure as suitable for cultivation in BLSS, were evaluated in terms of growth and production. Germination percentage and Mean Germination Time (MGT) were measured. Plants were cultivated in a growth chamber equipped with a recirculating hydroponic system (Nutrient Film Technique). Cultivation was performed under controlled environmental conditions (12 h photoperiod, light intensity 350 μmol m-2 s-1, temperature regime 26/20 °C light/dark, relative humidity 65-75%). Fertigation was performed with a standard Hoagland solution, modified for soybean specific requirements, and EC and pH were kept at 2.0 dS m-1 and 5.5 respectively. The percentage of germination was high (from 86.9% in 'Cresir' to 96.8% in 'Regir')and the MGT was similar for all the cultivars (4.3 days). The growing cycle lasted from 114 in 'Cresir' to 133 days on average in the other cultivars. Differences in plant size were recorded, with 'Pr91m10' plants being the shortest (58 vs 106 cm). Cultivars did not differ significantly in seed yield (12 g plant-1) and in non edible biomass (waste), water consumption and biomass conversion efficiency (water, radiation and acid use indexes). 'Pr91m10' showed the highest protein content in the seeds (35.6% vs 33.3% on average in the other cultivars). Results from the cultivation experiment showed good performances of the four cultivars in hydroponics. The overall analysis suggests that 'Pr91m10' could be the best candidate for the cultivation in a BLSS, coupling the small plant size and the good yield with high resource use efficiency and good seed quality.

  19. Soybean cultivation for Bioregenerative Life Support Systems (BLSSs): The effect of hydroponic system and nitrogen source

    NASA Astrophysics Data System (ADS)

    Paradiso, Roberta; Buonomo, Roberta; Dixon, Mike A.; Barbieri, Giancarlo; De Pascale, Stefania

    2014-02-01

    Soybean [Glycine max (L.) Merr.] is one of the plant species selected within the European Space Agency (ESA) Micro-Ecological Life Support System Alternative (MELiSSA) project for hydroponic cultivation in Biological Life Support Systems (BLSSs), because of the high nutritional value of seeds. Root symbiosis of soybean with Bradirhizobium japonicum contributes to plant nutrition in soil, providing ammonium through the bacterial fixation of atmospheric nitrogen. The aim of this study was to evaluate the effects of two hydroponic systems, Nutrient Film Technique (NFT) and cultivation on rockwool, and two nitrogen sources in the nutrient solution, nitrate (as Ca(NO3)2 and KNO3) and urea (CO(NH2)2), on root symbiosis, plant growth and seeds production of soybean. Plants of cultivar 'OT8914', inoculated with B. japonicum strain BUS-2, were grown in a growth chamber, under controlled environmental conditions. Cultivation on rockwool positively influenced root nodulation and plant growth and yield, without affecting the proximate composition of seeds, compared to NFT. Urea as the sole source of N drastically reduced the seed production and the harvest index of soybean plants, presumably because of ammonium toxicity, even though it enhanced root nodulation and increased the N content of seeds. In the view of large-scale cultivation for space colony on planetary surfaces, the possibility to use porous media, prepared using in situ resources, should be investigated. Urea can be included in the nutrient formulation for soybean in order to promote bacterial activity, however a proper ammonium/nitrate ratio should be maintained.

  20. [Effects of LED spectrum combinations on the absorption of mineral elements of hydroponic lettuce].

    PubMed

    Chen, Xiao-Li; Guo, Wen-Zhong; Xue, Xu-Zhang; Mmanake Beauty, Morewane

    2014-05-01

    Lettuce (Lactuca sativa) was hydroponically cultured in a completely enclosed plant factory, in which spectrum proportion-adjustable LED panels were used as sole light source for plant growth. Absorption and content of eleven mineral elements such as K, P, Ca, Mg, Na, Fe, Mn, Zn, Cu, B and Mo in Lactuca sativa under different spectral component conditions were studied by ICP -AES technology. The results showed that: (1) Single or combined spectrums corresponding to the absorbing peaks of chlorophyll a and b (450, 660 nm) could enhance the absorbing ability of roots especially for mineral elements Na, Fe, Mn, Cu and Mo, the single red spectrum had the most significant promoting effect under which contents of those four elements were respectively 7. 8, 4. 2, 4. 0 and 3. 7 times more than that under FL; (2) Absorption of K and B was the highest under FL which was 10. 309 mg g-1 and 32. 6 microg g-1 while the values decreased significantly under single or combined spectrum of red and blue; (3) Plants grown under single blue spectrum had the lowest absorption of Ca and Mg which respectively decreased by 35% and 33% than FL; (4) Lettuce grown under the spectrum combination of 30% blue and 70% red had the highest accumulations of biomass while those grown under 20% blue and 80% red had the highest accumulations of the following seven elements Ca, Mg, Na, Fe, Mn, Zn and B. The results provided theoretical basis for adjusting nutrient solution formula and selecting light spectrum of hydroponic lettuce. PMID:25095445

  1. Nonrecirculating hydroponic systems suitable for uptake studies at very low nutrient concentrations

    SciTech Connect

    Gutschick, V.P.; Kay, L.E. )

    1991-04-01

    The authors describe the mechanical, electronic, hydraulic, and structural design of a nonrecirculating hydroponic system. The system is particularly suited to sutides at very low nutrient concentratons, for which on-line concentration monitoring methods either do not exist or are costly and limited to monitoring relatively few indivitual plants. Solutions are mised automatically to chosen concentrations, which can be set differently for every pump fed from a master supply of deionized water and nutrient concentrates. Pumping rates can be varied over a 50-fold range, up to 400 liters per day, which suffices to maintain a number of large, post-seedling plants in rapid growth at (sub)micromolar levels of N and P. The outflow of each pump is divided among as many as 12 separate root chambers. In each changer one may monitor uptake by individual plant roots or segments thereof, by measuring nutrient depletion in batch samples of solution. The system is constructed from nontoxic materials that do not adsorb nutrient ions; no transient shifts of nitrate and phosphate concentrations are observable at the submicromolar level. Nonrecirculaton of solution limits porblems of pH shifts, microbial contamination, and cumulative imbalances in unmonitored nutrients. They note several disadvantages, principally related to high consumption of deionized water and solutes. The reciprocating pumps can be constructed inexpensively, particularly by the researcher. They also report previously unattainable control of passive temperature rise of chambers exposed to full sunlight, by use of white epoxy paint.

  2. In vivo bioavailability studies of sumatriptan succinate buccal tablets

    PubMed Central

    Shivanand, K; Raju, SA; Nizamuddin, S; Jayakar, B

    2011-01-01

    Back ground and the purpose of study Sumatriptan succinate is a Serotonin 5- HT1 receptor agonist, used in treatment of migraine. It is absorbed rapidly but incompletely when given orally and undergoes first-pass metabolism, resulting in a low absolute bioavailability of about 15%. The aim of this work was to design mucoadhesive bilayered buccal tablets of sumatriptan succinate to improve its bioavailability. Methods Mucoadhesive polymers carbopol 934 (Carbopol), HPMC K4M, HPMC K15M along with ethyl cellulose as an impermeable backing layer were used for the preparation of mucoadhesive bilayered tablets. In vivo bioavailability studies was also conducted in rabbits for optimized formulation using oral solution of sumatriptan succinate as standard. Results Bilayered buccal tablets (BBT) containing the mixture of Carbopol and HPMC K4M in the ratio 1:1 (T1) had the maximum percentage of in vitro drug release within 6 hrs. The optimized formulation (T1) followed non-Fickian release mechanism. The percentage relative bioavailability of sumatriptan succinate from selected bilayered buccal tablets (T1) was found to be 140.78%. Conclusions Bilayered buccal tablets of sumatriptan succinate was successfully prepared with improved bioavailability. PMID:22615661

  3. Beneficial effects of silicon on hydroponically grown corn salad (Valerianella locusta (L.) Laterr) plants.

    PubMed

    Gottardi, Stefano; Iacuzzo, Francesco; Tomasi, Nicola; Cortella, Giovanni; Manzocco, Lara; Pinton, Roberto; Römheld, Volker; Mimmo, Tanja; Scampicchio, Matteo; Dalla Costa, Luisa; Cesco, Stefano

    2012-07-01

    Soil-less cultivation of horticultural crops represents a fairly recent innovation to traditional agriculture which has several advantages including higher water-use efficiency. When plants are grown with this system, their roots come in contact with nutrients solely via the hydroponic solution. Although its beneficial effects have been widely demonstrated, silicon (Si) is mostly omitted from the composition of nutrient solutions. Therefore, the objective of this study was to assess the beneficial effect of Si addition to hydroponic solution on quali-quantitative aspects of edible production of two cultivars of corn salad (Valerianella locusta (L.) Laterr.) grown in soil-less floating system. Impacts on shelf life of this food were also studied. Results show that the supply of Si increased the edible yield and the quality level reducing the nitrate concentration in edible tissues. This result might be attributed to changes either in the metabolism (such as the nitrate assimilation process) or to the functionality of root mechanisms involved in the nutrient acquisition from the outer medium. In fact, our results show for the first time the ability of Si to modulate the root activity of nitrate and Fe uptake through, at least in part, a regulation of gene expression levels of the proteins involved in this phenomenon. In addition, the presence of Si decreased the levels of polyphenoloxidase gene expression at harvest and, in post-harvest, slowed down the chlorophyll degradation delaying leaf senescence and thus prolonging the shelf life of these edible tissues. In conclusion, data showed that the addition of Si to the nutrient solution can be a useful tool for improving quali-quantitatively the yield of baby leaf vegetable corn salad as well as its shelf life. Since the amelioration due to the Si has been achieved only with one cultivar, the recommendation of its inclusion in the nutrient solution does not exclude the identification of cultivars suitable for this

  4. Risperidone: effects of formulations on oral bioavailability.

    PubMed

    Gutierrez, R; Lee, P I; Huang, M L; Woestenborghs, R

    1997-01-01

    The bioavailability of risperidone was evaluated in an open-label, randomized, two-way, crossover study comparing a 1-mg tablet with a 1-mg/ml oral solution. Both formulations were administered as a single 1-mg dose with a 10-day washout period between treatments. Of 26 healthy men who entered the study, 23 completed both treatment periods. Plasma concentrations of risperidone and the active moiety (risperidone plus its active metabolite, 9-hydroxyrisperidone) were determined by radioimmunoassays. For key pharmacokinetic values (Cmax, AUC), the 90% CIs on the relative bioequivalence of risperidone, 9-hydroxyrisperidone, and the active moiety were contained within the equivalence range of 80-120% (80-125% for log-transformed data). The results demonstrate that the 1-mg/ml oral solution and the 1-mg tablet are bioequivalent. PMID:9165565

  5. Stimulating productivity of hydroponic lettuce in controlled environments with triacontanol

    NASA Technical Reports Server (NTRS)

    Knight, S. L.; Mitchell, C. A.

    1987-01-01

    Triacontanol (1-triacontanol) applied as a foliar spray at 10(-7) M to 4-day-old, hydroponically grown leaf lettuce (Lactuca sativa L.) seedlings in a controlled environment increased leaf fresh and dry weight 13% to 20% and root fresh and dry weight 13% to 24% 6 days after application, relative to plants sprayed with water. When applied at 8 as well as 4 days after seeding, triacontanol increased plant fresh and dry weight, leaf area, and mean relative growth rate 12% to 37%. There was no benefit of repeating application of triacontanol in terms of leaf dry weight gain.

  6. Photosynthetic Response to Long- and Short-Term Changes in Carbon Dioxide in Sweetpotatoes Grown Hydroponically with Enhanced Mineral Nutrition

    NASA Technical Reports Server (NTRS)

    Hamilton, Casey; Terse, Anita; Hileman, Douglas R.; Mortley, Desmond G.; Hill, Jill

    1998-01-01

    Sweetpotato [Ipomoea batatas L.(Lam.)] has been selected by NASA as a potential food for long-term space missions. In previous experiments, sweetpotato plants grown hydroponically under elevated levels of CO2 depleted the nitrogen in the nutrient solution between the hi-weekly solution replacements. In this experiment, the effect of enhanced nutrient replenishment on photosynthetic rates of sweetpotato was determined. CO2 response curves were determined for "TU-82-155" and "Georgia-Jet" sweetpotatoes grown hydroponically in growth chambers at three different CO2 concentrations (400, 750, and 1000 micro-mol/mol CO2). Gas exchange measurements were made using infrared gas analysis, an open-flow gas exchange system, and a controlled-climate cuvette. Photosynthetic measurements were made at CO2 concentrations from 50-1000 micro-mol/mol CO2. Net photosynthetic rates showed an increase with increasing measurement CO2 in all nutrient regimes, but the response of photosynthetic rates to the growth CO2 conditions varied among the experiments and between the two varieties. Enhanced mineral nutrition led to increased net photosynthetic rates in "Georgia Jet" plants, but not in "TU-82-155" plants. The results of this study will help to determine the CO2 requirements for growth of sweetpotato on proposed space missions.

  7. BIOSURFACES AND BIOAVAILABILITY: A NANOSCALE OVERVIEW

    EPA Science Inventory

    Environmentally, contaminant bioavailability is a key parameter in determining exposure assessment and ultimately risk assessment/risk management. Defining bioavailability requires knowledge of the contaminant spatial/temporal disposition and transportability and the thermodyna...

  8. Effect of water velocity on hydroponic phytoremediation of metals.

    PubMed

    Weiss, P; Westbrook, A; Weiss, J; Gulliver, J; Biesboer, D

    2014-01-01

    The influence of flow velocity on the uptake of cadmium, copper, lead, and zinc by hydroponically grown soft stem bulrush (Scirpus validus) was investigated. The roots of the plants were exposed to a continually recycled, nutrient enriched, synthetic stormwater. Plants were divided into groups and the roots of each group exposed to different but constant water velocities. The metal concentrations in the roots and stems were compared after three weeks. Metal accumulation in roots was increased for water velocities between 1.3 and 4.0 cm s(-1). In a second experiment, the roots of all plants were exposed to a single velocity and the root and stem metal concentrations were determined as a function of time. Metal concentrations in the roots approached a constant value after three weeks. After this time, accumulation of metals depends upon root growth. The results suggest that long-term accumulation by the roots of hydroponic Scirpus validus can be increased by increasing water velocity, which implies that floating islands with movement will retain more metals from the water column. PMID:24912210

  9. Incorporating bioavailability into toxicity assessment of Cu-Ni, Cu-Cd, and Ni-Cd mixtures with the extended biotic ligand model and the WHAM-F(tox) approach.

    PubMed

    Qiu, Hao; Vijver, Martina G; He, Erkai; Liu, Yang; Wang, Peng; Xia, Bing; Smolders, Erik; Versieren, Liske; Peijnenburg, Willie J G M

    2015-12-01

    There are only a limited number of studies that have developed appropriate models which incorporate bioavailability to estimate mixture toxicity. Here, we explored the applicability of the extended biotic ligand model (BLM) and the WHAM-F(tox) approach for predicting and interpreting mixture toxicity, with the assumption that interactions between metal ions obey the BLM theory. Seedlings of lettuce Lactuca sativa were exposed to metal mixtures (Cu-Ni, Cu-Cd, and Ni-Cd) contained in hydroponic solutions for 4 days. Inhibition to root elongation was the endpoint used to quantify the toxic response. Assuming that metal ions compete with each other for binding at a single biotic ligand, the extended BLM succeeded in predicting toxicity of three mixtures to lettuce, with more than 82% of toxicity variation explained. There were no significant differences in the values of f(mix50) (i.e., the overall amounts of metal ions bound to the biotic ligand inducing 50% effect) for the three mixture combinations, showing the possibility of extrapolating these values to other binary metal combinations. The WHAM-F(tox) approach showed a similar level of precision in estimating mixture toxicity while requiring fewer parameters than the BLM-f(mix) model. External validation of the WHAM-F(tox) approach using literature data showed its applicability for other species and other mixtures. The WHAM-F(tox) model is suitable for delineating mixture effects where the extended BLM also applies. Therefore, in case of lower data availability, we recommend the lower parameterized WHAM-F(tox) as an effective approach to incorporate bioavailability in quantifying mixture toxicity. PMID:26250821

  10. Bioavailability of Promethazine during Spaceflight

    NASA Technical Reports Server (NTRS)

    Boyd, Jason L.; Wang, Zuwei; Putcha, Lakshmi

    2009-01-01

    Promethazine (PMZ) is the choice anti-motion sickness medication for treating space motion sickness (SMS) during flight. The side effects associated with PMZ include dizziness, drowsiness, sedation, and impaired psychomotor performance which could impact crew performance and mission operations. Early anecdotal reports from crewmembers indicate that these central nervous system side effects of PMZ are absent or greatly attenuated in microgravity, potentially due to changes in pharmacokinetics (PK) and pharmacodynamics in microgravity. These changes could also affect the therapeutic effectiveness of drugs in general and PMZ, in particular. In this investigation, we examined bioavailability and associated pharmacokinetics of PMZ in astronauts during and after space flight. Methods. Nine astronauts received, per their preference, PMZ (25 or 50 mg as intramuscular injection, oral tablet, or rectal suppository) on flight day one for the treatment of SMS and subsequently collected saliva samples and completed sleepiness scores for 72 h post dose. Thirty days after the astronauts returned to Earth, they repeated the protocol. Bioavailability and PK parameters were calculated and compared between flight and ground. Results. Maximum concentration (Cmax) was lower and time to reach Cmax (tmax) was longer in flight than on the ground. Area under the curve (AUC), a measure of bioavailability, was lower and biological half-life (t1/2) was longer in flight than on the ground. Conclusion. Results indicate that bioavailability of PMZ is reduced during spaceflight. Number of samples, sampling method, and sampling schedule significantly affected PK parameter estimates.

  11. [Bioavailability and metabolism of flavonoids].

    PubMed

    Makarova, M N

    2011-01-01

    In the review the modern data about bioavailability and a metabolism of flavonoids is considered. The data about absorption flavonoids in a digestive path, participation of microorganisms in their hydrolysis, pharmacokinetic the data on the basic classes flavonoids: flavanes (flavan-3-ols), anthocyanes, flavones, flavonols and flavanones is cited. PMID:21842747

  12. [Bioavailability and metabolism of flavonoids].

    PubMed

    Makarova, N M

    2011-01-01

    Published data about bioavailability and metabolism of flavonoids are reviewed. Information concerning the absorption of flavonoids in a digestive path and the participation of microorganisms in their hydrolysis is summarized. Parameters of pharmacokinetics are presented for the main classes of flavonoids, including flavanes (flavan-3-ols), anthocyans, flavones, flavonols, and flavanones. PMID:21870774

  13. Drug Bioavailability Data: (Un)Available.

    ERIC Educational Resources Information Center

    Capomacchia, Anthony C.; And Others

    1979-01-01

    The obtainability of drug bioavailability data from both brand-name and generic-drug manufacturers was studied to document the relative change in availability to pharmacy students of drug bioavailability data between 1978 and 1976 for drugs exhibiting bioavailability problems. The results indicate no major change. (JMD)

  14. Evaluation of the toxicity of selenium from hydroponically produced selenium-enriched kale sprout in laying hens.

    PubMed

    Chantiratikul, Anut; Borisuth, Lalita; Chinrasri, Orawan; Saenthaweesuk, Nattanan; Chookhampaeng, Sumalee; Thosaikham, Witphon; Sriart, Noppong; Chantiratikul, Piyanete

    2016-05-01

    Hydroponically produced Se-enriched kale sprouts (HPSeKS) are studied for their use as an alternative dietary Se supplement for poultry. The study experimented with different levels and sources of Se to determine toxicity and how the toxicity may affect productive performance, Se concentration in egg and tissues, and physiological responses of laying hens. One-hundred and twenty hens, 59 weeks of age, were divided into 5 groups. Each group consisted of 4 replicates and each replicate had 6 birds according to a 2×2+1 Augmented Factorial Experiment in a Completely Randomized Design. The experiment was conducted over a 4 week period, and 5 dietary treatments (T) were used: T1 basal diet, T2 and T3 basal diet plus 5 and 10mg Se/kg from sodium selenite (SS), T4 and T5 basal diet plus 5 and 10mg Se/kg from HPSeKS, respectively. The results make clear that Se from HPSeKS, at 5-10mg/kg, did not affect (P>0.05) feed intake and egg production; however, Se bioavailability decreased (P<0.05). Egg, tissue and plasma Se concentrations, and GSH-Px activity in red blood cells increased (P<0.05) compared to those in T1. Final body weight, feed intake, Se bioavailability, concentration of Se in breast muscle and plasma of hens fed Se from SS were lower (P<0.05) than those of hens fed Se from HPSeKS. The findings demonstrate that dietary Se from HPSeKS at 5-10mg/kg is not considered a toxic level for laying hens. The toxicity of Se from HPSeKS was less than the toxicity of Se from SS. PMID:26964695

  15. Recycling of inorganic nutrients for hydroponic crop production following incineration of inedible biomass.

    PubMed

    Bubenheim, D L; Wignarajah, K

    1997-01-01

    The goal of resource recovery in a regenerative life support system is maintenance of product quality to sure support of reliable and predictable levels of life support function performance by the crop plant component. Further, these systems must be maintained over extended periods of time, requiring maintenance of nutrient solutions to avoid toxicity and deficiencies. The focus of this study was to determine the suitability of the ash product following incineration of inedible biomass as a source of inorganic nutrients for hydroponic crop production. Inedible wheat biomass was incinerated and ash quality characterized. The incinerator ash was dissolved in adequate nitric acid to establish a consistent nitrogen concentration is all nutrient solution treatments. Four experimental nutrient treatments were included: control, ash only, ash supplemented to match the control treatment, and ash only quality formulated with reagent grade chemicals. When nutrient solutions were formulated using only ash following incineration of inedible biomass, a balance in solution is established representing elemental retention following incineration and nutrient proportions present in the original biomass. The resulting solution is not identical to the control. This imbalance resulted in a suppression of crop growth. When the ash is supplemented with reagent grade chemicals to establish the same balance as in the control--growth is identical to the control. The ash appears to carry no phytotoxic materials. Growth in solution formulated with reagent grade chemicals but matching the quality of the ash only treatment resulted in similar growth to that of the ash only treatment. The ash product resulting from incineration of inedible biomass appears to be a suitable form for recycle of inorganic nutrients to crop production. PMID:11542586

  16. Recycling of inorganic nutrients for hydroponic crop production following incineration of inedible biomass

    NASA Astrophysics Data System (ADS)

    Bubenheim, D. L.; Wignarajah, K.

    1997-01-01

    The goal of resource recovery in a regenerative life support system is maintenance of product quality to insure support of reliable and predictable levels of life support function performance by the crop plant component. Further, these systems must be maintained over extended periods of time, requiring maintenance of nutrient solutions to avoid toxicity and deficiencies. The focus of this study was to determine the suitability of the ash product following incineration of inedible biomass as a source of inorganic nutrients for hydroponic crop production. Inedible wheat biomass was incinerated and ash quality characterized. The incinerator ash was dissolved in adequate nitric acid to establish a consistent nitrogen concentration is all nutrient solution treatments. Four experimental nutrient treatments were included: control, ash only, ash supplemented to match the control treatment, and ash only quality formulated with reagent grade chemicals. When nutrient solutions were formulated using only ash following incineration of inedible biomass, a balance in solution is established representing elemental retention following incineration and nutrient proportions present in the original biomass. The resulting solution is not identical to the control. This imbalance resulted in a suppression of crop growth. When the ash is supplemented with reagent grade chemicals to establish the same balance as in the control - growth is identical to the control. The ash appears to carry no phytotoxic materials. Growth in solution formulated with reagent grade chemicals but matching the quality of the ash only treatment resulted in similar growth to that of the ash only treatment. The ash product resulting from incineration of inedible biomass appears to be a suitable form for recycle of inorganic nutrients to crop production.

  17. Role of plants in nitrogen and sulfur transformations in floating hydroponic root mats: A comparison of two helophytes.

    PubMed

    Saad, Rania A B; Kuschk, Peter; Wiessner, Arndt; Kappelmeyer, Uwe; Müller, Jochen A; Köser, Heinz

    2016-10-01

    Knowledge about the roles helophytes play in constructed wetlands (CWs) is limited, especially regarding their provision of organic rhizodeposits. Here, transformations of inorganic nitrogen and sulfur were monitored in a CW variety, floating hydroponic root mat (FHRM), treating synthetic wastewater containing low concentration of organic carbon. Two helophytes, Phragmites australis and Juncus effusus, were compared in duplicates. Striking differences were found between the FHRM of the two helophytes. Whereas ammonium was removed in all FHRMs to below detection level, total nitrogen of 1.15 ± 0.4 g m(-2) d(-1) was removed completely only in P. australis systems. The mats with J. effusus displayed effective nitrification but incomplete denitrification as 77% of the removed ammonium-nitrogen accumulated as nitrate. Furthermore, the P. australis treatment units showed on average 3 times higher sulfate-S removal rates (1.1 ± 0.45 g m(-2) d(-1)) than the systems planted with J. effusus (0.37 ± 0.29 g m(-2) d(-1)). Since the influent organic carbon was below the stoichiometric requirement for the observed N and S transformation processes, helophytes' organic rhizodeposits apparently contributed to these transformations, while P. australis provided about 6 times higher bioavailable organic rhizodeposits than J. effusus. PMID:27393940

  18. Bioavailability of the polyphenols: status and controversies.

    PubMed

    D'Archivio, Massimo; Filesi, Carmelina; Varì, Rosaria; Scazzocchio, Beatrice; Masella, Roberta

    2010-01-01

    The current interest in polyphenols has been driven primarily by epidemiological studies. However, to establish conclusive evidence for the effectiveness of dietary polyphenols in disease prevention, it is useful to better define the bioavailability of the polyphenols, so that their biological activity can be evaluated. The bioavailability appears to differ greatly among the various phenolic compounds, and the most abundant ones in our diet are not necessarily those that have the best bioavailability profile. In the present review, we focus on the factors influencing the bioavailability of the polyphenols. Moreover, a critical overview on the difficulties and the controversies of the studies on the bioavailability is discussed. PMID:20480022

  19. Bioavailability of the Polyphenols: Status and Controversies

    PubMed Central

    D’Archivio, Massimo; Filesi, Carmelina; Varì, Rosaria; Scazzocchio, Beatrice; Masella, Roberta

    2010-01-01

    The current interest in polyphenols has been driven primarily by epidemiological studies. However, to establish conclusive evidence for the effectiveness of dietary polyphenols in disease prevention, it is useful to better define the bioavailability of the polyphenols, so that their biological activity can be evaluated. The bioavailability appears to differ greatly among the various phenolic compounds, and the most abundant ones in our diet are not necessarily those that have the best bioavailability profile. In the present review, we focus on the factors influencing the bioavailability of the polyphenols. Moreover, a critical overview on the difficulties and the controversies of the studies on the bioavailability is discussed. PMID:20480022

  20. Salinity Reduction and Biomass Accumulation in Hydroponic Growth of Purslane (Portulaca oleracea).

    PubMed

    de Lacerda, Laís Pessôa; Lange, Liséte Celina; Costa França, Marcel Giovanni; Zonta, Everaldo

    2015-01-01

    In many of the world's semi-arid and arid regions, the increase in demand for good quality water associated with the gradual and irreversible salinisation of the soil and water have raised the development of techniques that facilitate the safe use of brackish and saline waters for agronomic purposes. This study aimed to evaluate the salinity reduction of experimental saline solutions through the ions uptake capability of purslane (Portulaca oleracea), as well as its biomass accumulation. The hydroponic system used contained three different nutrient solutions composed of fixed concentrations of macro and micronutrients to which three different concentrations of sodium chloride had been added. Two conditions were tested, clipped and intact plants. It was observed that despite there being a notable removal of magnesium and elevated biomass accumulation, especially in the intact plants, purslane did not present the expected removal quantity of sodium and chloride. We confirmed that in the research conditions of the present study, purslane is a saline-tolerant species but accumulation of sodium and chloride was not shown as previously described in the literature. PMID:25397981

  1. Cadmium accumulation by jack-bean and sorghum in hydroponic culture.

    PubMed

    Francato Zancheta, Ariana Carramaschi; De Abreu, Cleide Aparecida; Zambrosi, Fernando César Bachiega; de Magalhães Erismann, Norma; Andrade Lagôa, Ana Maria Magalhães

    2015-01-01

    Among the technologies used to recuperate cadmium (Cd) contaminated soils, phytoextraction are particularly important, where the selection of suitable plants is critical to the success of the soil remediation. Thus, the objectives of this study were to evaluate the responses of jack-bean and sorghum to Cd supply and to quantify Cd accumulation by these species grown in hydroponic culture. The plants were subjected to 0, 15, 30, or 60 μmol Cd L(-1) in the nutrient solution, and gas exchange, plant growth and Cd accumulation were measured at 25 days after starting Cd treatments. The Cd supply severely reduced growth of shoots and roots in both species. In jack-bean, Cd decreased photosynthesis by 56-86%, stomatal conductance by 59-85% and transpiration by 48-80%. The concentrations and amounts of Cd accumulated in the plant tissues were proportional to the metal supply in the nutrient solution. Sorghum was more tolerant than jack-bean to Cd toxicity, but the latter showed a greater metal concentration and accumulation in the shoot. Therefore, jack-bean would be more suitable than sorghum for use in Cd phytoremediation programs based on phytoextraction. PMID:25397989

  2. Root uptake and translocation of perfluorinated alkyl acids by three hydroponically grown crops.

    PubMed

    Felizeter, Sebastian; McLachlan, Michael S; De Voogt, Pim

    2014-04-16

    Tomato, cabbage, and zucchini plants were grown hydroponically in a greenhouse. They were exposed to 14 perfluorinated alkyl acids (PFAAs) at four different concentrations via the nutrient solution. At maturity the plants were harvested, and the roots, stems, leaves, twigs (where applicable), and edible parts (tomatoes, cabbage head, zucchinis) were analyzed separately. Uptake and transfer factors were calculated for all plant parts to assess PFAA translocation and distribution within the plants. Root concentration factors were highest for long-chain PFAAs (>C11) in all three plant species, but these chemicals were not found in the edible parts. All other PFAAs were present in all above-ground plant parts, with transpiration stream concentration factors (TSCFs) of 0.05-0.25. These PFAAs are taken up with the transpiration stream and accumulate primarily in the leaves. Although some systematic differences were observed, overall their uptake from nutrient solution to roots and their further distribution within the plants were similar between plant species and among PFAAs. PMID:24646206

  3. Influence of two types of organic matter on interaction of CeO2 nanoparticles with plants in hydroponic culture.

    PubMed

    Schwabe, Franziska; Schulin, Rainer; Limbach, Ludwig K; Stark, Wendelin; Bürge, Diane; Nowack, Bernd

    2013-04-01

    An important aspect in risk assessment of nanoparticles (NPs) is to understand their environmental interactions. We used hydroponic plant cultures to study nanoparticle-plant-root interaction and translocation and exposed wheat and pumpkin to suspensions of uncoated CeO2-NP for 8d (primary particle size 17-100 nm, 100 mg L(-1)) in the absence and presence of fulvic acid (FA) and gum arabic (GA) as representatives of different types of natural organic matter. The behavior of CeO2-NPs in the hydroponic solution was monitored regarding agglomeration, sedimentation, particle size distribution, surface charge, amounts of root association, and translocation into shoots. NP-dispersions were stable over 8d in the presence of FA or GA, but with growing plants, changes in pH, particle agglomeration rate, and hydrodynamic diameter were observed. None of the plants exhibited reduced growth or any toxic response during the experiment. We found that CeO2-NPs translocated into pumpkin shoots, whereas this did not occur in wheat plants. The presence of FA and GA affected the amount of CeO2 associated with roots (pure>FA>GA) but did not affect the translocation factor. Additionally, we could confirm via TEM and SEM that CeO2-NPs adhered strongly to root surfaces of both plant species. PMID:23352517

  4. Comparison of aerobically-treated and untreated crop residue as a source of recycled nutrients in a recirculating hydroponic system

    NASA Technical Reports Server (NTRS)

    Mackowiak, C. L.; Garland, J. L.; Strayer, R. F.; Finger, B. W.; Wheeler, R. M.

    1996-01-01

    This study compared the growth of potato plants on nutrients recycled from inedible potato biomass. Plants were grown for 105 days in recirculating, thin-film hydroponic systems containing four separate nutrient solution treatments: (1) modified half-strength Hoagland's (control), 2) liquid effluent from a bioreactor containing inedible potato biomass, 3) filtered (0.2 micrometer) effluent, and 4) the water soluble fraction of inedible potato biomass (leachate). Approximately 50% of the total nutrient requirement in treatments 2-4 were provided (recycled) from the potato biomass. Leachate had an inhibitory effect on leaf conductance, photosynthetic rate, and growth (50% reduction in plant height and 60% reduction in tuber yield). Plants grown on bioreactor effluent (filtered or unfiltered) were similar to the control plants. These results indicated that rapidly degraded, water soluble organic material contained in the inedible biomass, i.e., material in leachate, brought about phytotoxicity in the hydroponic culture of potato. Recalcitrant, water soluble organic material accumulated in all nutrient recycling treatments (650% increase after 105 days), but no increase in rhizosphere microbial numbers was observed.

  5. Potential for phytoextraction of copper by Sinapis alba and Festuca rubra cv. Merlin grown hydroponically and in vineyard soils.

    PubMed

    Malagoli, Mario; Rossignolo, Virginia; Salvalaggio, Nico; Schiavon, Michela

    2014-03-01

    The extensive use of copper-bearing fungicides in vineyards is responsible for the accumulation of copper (Cu) in soils. Grass species able to accumulate Cu could be cultivated in the vineyard inter-rows for copper phytoextraction. In this study, the capacity of Festuca rubra cv Merlin and Sinapis alba to tolerate and accumulate copper (Cu) was first investigated in a hydroponic system without the interference of soil chemical-physical properties. After the amendment of Cu (5 or 10 mg Cu l-(1)) to nutrient solution, shoot Cu concentration in F. rubra increased up to 108.63 mg Cu kg(-1) DW, more than three times higher than in S. alba (31.56 mg Cu kg(-1) DW). The relationship between Cu concentration in plants and external Cu was dose-dependent and species specific. Results obtained from the hydroponic experiment were confirmed by growing plants in pots containing soil collected from six Italian vineyards. The content of soil organic matter was crucial to enhance Cu tolerance and accumulation in the shoot tissues of both plant species. Although S. alba produced more biomass than F. rubra in most soils, F. rubra accumulated significantly more Cu (up to threefold to fourfold) in the shoots. Given these results, we recommended that F. rubra cv Merlin could be cultivated in the vineyard rows to reduce excess Cu in vineyard soils. PMID:24234763

  6. Comparison of aerobically-treated and untreated crop residue as a source of recycled nutrients in a recirculating hydroponic system

    NASA Astrophysics Data System (ADS)

    Mackowiak, C. L.; Garland, J. L.; Strayer, R. F.; Finger, B. W.; Wheeler, R. M.

    1996-01-01

    This study compared the growth of potato plants on nutrients recycled from inedible potato biomass. Plants were grown for 105 days in recirculating, thin-film hydroponic systems containing four separate nutrient solution treatments: 1) modified half-strength Hoagland's (control), 2) liquid effluent from a bioreactor containing inedible potato biomass, 3) filtered (0.2 μm) effluent, and 4) the water soluble fraction of inedible potato biomass (leachate). Approximately 50% of the total nutrient requirement in treatments 2 - 4 were provided (recycled) from the potato biomass. Leachate had an inhibitory effect on leaf conductance, photosynthetic rate, and growth (50% reduction in plant height and 60% reduction in tuber yield). Plants grown on bioreactor effluent (filtered or unfiltered) were similar to the control plants. These results indicated that rapidly degraded, water soluble organic material contained in the inedible biomass, i.e., material in leachate, brought about phytotoxicity in the hydroponic culture of potato. Recalcitrant, water soluble organic material accumulated in all nutrient recycling treatments (650% increase after 105 days), but no increase in rhizosphere microbial numbers was observed.

  7. Fate of the explosive hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) in soil and bioaccumulation in bush bean hydroponic plants

    SciTech Connect

    Harvey, S.D.; Fellows, R.J.; Cataldo, D.A.; Bean, R.M. )

    1991-01-01

    Soils amended with [[sup 14]C]hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) were sampled over 60 d and subjected to exhaustive Soxhlet extraction followed by HPLC analysis. RDX was the only radiolabeled compound observed in soil extracts. Emission of volatile organics and [sup 14]CO[sub 2] from soil accounted for only 0.31 % of the amended radiolabel. Mass balance for RDX-amended soil was better than 84% throughout the two-month study. The analytical method developed for plants involved acid hydrolysis, solvent extraction, fractionation on Florisil adsorbent and separation by HPLC. The described methodology allowed for RDX recovery of 86 [+-] 3% from fortified bush bean leaf tissue. Further experiments were conducted with bush bean plants maintained on RDX-containing hydroponic solutions. Hydroponic plants did not emit detectable amounts of [sup 14]CO[sub 2] or radiolabeled volatile organics. Analysis of the plant tissue indicated bioaccumulation of RDX in the aerial tissues of hydroponic plants exposed for either 1 or 7 d. Metabolism of RDX to polar metabolites was observed in plants exposed for 7 d.

  8. Influence of nitrogen nutrition management on biomass partitioning and nitrogen use efficiency indices in hydroponically grown potato

    NASA Technical Reports Server (NTRS)

    Goins, Gregory D.; Yorio, Neil C.; Wheeler, Raymond M.

    2004-01-01

    The National Aeronautics and Space Administration (NASA) has been conducting controlled environment research with potatoes (Solanum tuberosum L.) in recirculating nutrient film technique (NFT)-hydroponic systems as a human life support component during long-duration spaceflight. Standard nutrient solution management approaches include constant pH regulation with nitric acid (HNO3) and daily adjustment of electrical conductivity (EC) equivalent to half-strength modified Hoagland's solution, where nitrate (NO3-) is the sole nitrogen (N) source. Although tuber yields have been excellent with such an approach, N use efficiency indices are expected to be low relative to tuber biomass production. Furthermore, the high amount of N used in NFT-hydroponics, typically results in high inedible biomass, which conflicts with the need to minimize system mass, volume, and expenditure of resources for long-duration missions. More effective strategies of N fertilization need to be developed to more closely match N supply with demand of the crop. Hence, the primary objective of this study was to identify the optimal N management regime and plant N requirement to achieve high yields and to avoid inefficient use of N and excess inedible biomass production. In separate 84-day cropping experiments, three N management protocols were tested. Treatments which decreased NO3(-)-N supply indirectly through lowering nutrient solution EC (Expt. I), or disabling pH control, and/or supplying NH4(+)-N (Expt. III) did not significantly benefit tuber yield, but did influence N use efficiency indices. When supplied with an external 7.5 mM NO3(-)-N for the first 42 days after planting (DAP), lowered to 1.0 mM NO3(-)-N during the final 42 days (Expt. II), plants were able to achieve yields on par with plants which received constant 7.5 mM NO3(-)-N (control). By abruptly decreasing N supply at tuber initiation in Expt. II, less N was taken up and accumulated by plants compared to those which received

  9. Influence of nitrogen nutrition management on biomass partitioning and nitrogen use efficiency indices in hydroponically grown potato.

    PubMed

    Goins, Gregory D; Yorio, Neil C; Wheeler, Raymond M

    2004-01-01

    The National Aeronautics and Space Administration (NASA) has been conducting controlled environment research with potatoes (Solanum tuberosum L.) in recirculating nutrient film technique (NFT)-hydroponic systems as a human life support component during long-duration spaceflight. Standard nutrient solution management approaches include constant pH regulation with nitric acid (HNO3) and daily adjustment of electrical conductivity (EC) equivalent to half-strength modified Hoagland's solution, where nitrate (NO3-) is the sole nitrogen (N) source. Although tuber yields have been excellent with such an approach, N use efficiency indices are expected to be low relative to tuber biomass production. Furthermore, the high amount of N used in NFT-hydroponics, typically results in high inedible biomass, which conflicts with the need to minimize system mass, volume, and expenditure of resources for long-duration missions. More effective strategies of N fertilization need to be developed to more closely match N supply with demand of the crop. Hence, the primary objective of this study was to identify the optimal N management regime and plant N requirement to achieve high yields and to avoid inefficient use of N and excess inedible biomass production. In separate 84-day cropping experiments, three N management protocols were tested. Treatments which decreased NO3(-)-N supply indirectly through lowering nutrient solution EC (Expt. I), or disabling pH control, and/or supplying NH4(+)-N (Expt. III) did not significantly benefit tuber yield, but did influence N use efficiency indices. When supplied with an external 7.5 mM NO3(-)-N for the first 42 days after planting (DAP), lowered to 1.0 mM NO3(-)-N during the final 42 days (Expt. II), plants were able to achieve yields on par with plants which received constant 7.5 mM NO3(-)-N (control). By abruptly decreasing N supply at tuber initiation in Expt. II, less N was taken up and accumulated by plants compared to those which received

  10. Removal of carbaryl, linuron, and permethrin by Lupinus angustifolius under hydroponic conditions.

    PubMed

    Garcinuño, R M; Fernandez Hernando, P; Camara, C

    2006-07-12

    The metabolism of organic pollutants by plants normally requires contaminant direct uptake by cells. Factors affecting this uptake and the later distribution of chemicals within the plant include the physicochemical properties of the compounds (concentration, structure, solubility, log k(ow), diffusion rate) and the biochemical characteristics of the plant. This paper reports the tolerance, uptake, and effects of the pesticides carbaryl, linuron, and permethrin on Lupinus angustifolius germination and growth as well as contaminant intraplant distribution and possible degradation. Lupine plants were grown in hydroponic culture containing either 1 or 5 mg of the individual pesticides, or combinations of these (1, 5, or 10 mg of each), in 100 mL nutrient and water solutions. Analysis of the remaining solutions 8 days post-germination showed the water solutions to have higher remaining pesticide concentrations than nutrient solutions. Furthermore, in the presence of pesticides, germination was more frequent in the water solutions. After 16 days of growth, the plants were harvested, and their tissues were microwaved digested and analyzed by reversed-phase liquid chromatography. Although only minor quantities of each pesticide were detected in plant tissues, their amount in the roots was higher than in the stems. No accumulation was noted in the cotyledons, and only 2% of linuron was detected in the leaves. Mass recovery at the end of the experiment showed that 57, 53, and 55% of carbaryl, linuron, and permethrin, respectively, were degraded and/or bound in an irreversible manner to plant material. The results suggest that L. angustifolius could be useful for the cleaning/remediation of pesticide-contaminated water. PMID:16819913

  11. Recycling crop residues for use in recirculating hydroponic crop production

    NASA Technical Reports Server (NTRS)

    Mackowiak, C. L.; Garland, J. L.; Sager, J. C.

    1996-01-01

    As part of bioregenerative life support feasibility testing by NASA, crop residues are being used to resupply elemental nutrients to recirculating hydroponic crop production systems. Methods for recovering nutrients from crop residues have evolved from water soaking (leaching) to rapid aerobic bioreactor processing. Leaching residues recovered the majority of elements but it also recovered significant amounts of soluble organics. The high organic content of leachates was detrimental to plant growth. Aerobic bioreactor processing reduced the organic content ten-fold, which reduced or eliminated phytotoxic effects. Wheat and potato production studies were successful using effluents from reactors having with 8- to 1-day retention times. Aerobic bioreactor effluents supplied at least half of the crops elemental mass needs in these studies. Descriptions of leachate and effluent mineral content, biomass productivity, microbial activity, and nutrient budgets for potato and wheat are presented.

  12. Variation characteristics of chlorpyrifos in nonsterile wetland plant hydroponic system.

    PubMed

    Wang, Chuan; Zhou, Qiaohong; Zhang, Liping; Zhang, Yan; Xiao, Enrong; Wu, Zhenbin

    2013-01-01

    Six wetland plants were investigated for their effect on the degradation characteristics of chlorpyrifos in nonsterile hydroponic system at constant temperature of 28 degrees C. The results showed that the removal rates of chlorpyrifos in the water of plant systems were 1.26-5.56% higher than that in the control without plants. Scirpus validus and Typha angustifolia were better than other hygrophytes in elimination of chlorpyrifos. The removal rates of the two systems were up to 88%. Plants of acaulescent group had an advantage over caulescent group in removing chlorpyrifos. Phytoaccumulation of chlorpyrifos was observed, and the order of chlorpyrifos concentration in different plant tissues was root > stem > leaf. It was also found that chlorpyrifos and its metabolite TCP decreased rapidly at the initial step of the experiment. PMID:23819296

  13. Recycling crop residues for use in recirculating hydroponic crop production.

    PubMed

    Mackowiak, C L; Garland, J L; Sager, J C

    1996-12-01

    As part of bioregenerative life support feasibility testing by NASA, crop residues are being used to resupply elemental nutrients to recirculating hydroponic crop production systems. Methods for recovering nutrients from crop residues have evolved from water soaking (leaching) to rapid aerobic bioreactor processing. Leaching residues recovered the majority of elements but it also recovered significant amounts of soluble organics. The high organic content of leachates was detrimental to plant growth. Aerobic bioreactor processing reduced the organic content ten-fold, which reduced or eliminated phytotoxic effects. Wheat and potato production studies were successful using effluents from reactors having with 8- to 1-day retention times. Aerobic bioreactor effluents supplied at least half of the crops elemental mass needs in these studies. Descriptions of leachate and effluent mineral content, biomass productivity, microbial activity, and nutrient budgets for potato and wheat are presented. PMID:11541570

  14. A hydroponic method for plant growth in microgravity

    NASA Technical Reports Server (NTRS)

    Wright, B. D.

    1985-01-01

    A hydroponic apparatus under development for long-term microgravity plant growth is described. The capillary effect root environment system (CERES) is designed to keep separate the nutrient and air flows, although both must be simultaneously available to the roots. Water at a pressure slightly under air pressure is allowed to seep into a plastic depression covered by a plastic screen and a porous membrane. A root in the air on the membrane outer surface draws the moisture through it. The laboratory model has a wire-based 1.241 mm mesh polyethylene screen and a filter membrane with 0.45 micron pores, small enough to prohibit root hair penetration. The design eliminates the need to seal-off the plant environment. Problems still needing attention include scaling up of the CERES size, controlling biofouling of the membrane, and extending the applications to plants without fibrous root systems.

  15. Possible Internalization of an Enterovirus in Hydroponically Grown Lettuce.

    PubMed

    Carducci, Annalaura; Caponi, Elisa; Ciurli, Adriana; Verani, Marco

    2015-07-01

    Several studies have shown that enteric viruses can be transferred onto the surface of vegetables and fruits through spray irrigation, but, recently, reports have suggested viral contamination of vegetables sub-irrigated with reused wastewater. Hydroponic cultures, used to grow ready to eat fresh lettuce, have also been used to study the possibility of viral absorption through roots. This study was conducted to assess a possible risk of viral contamination in lettuce from contaminated water. The leaves of lettuce plants grown in hydroponic cultures where the roots were exposed to water containing Coxsakievirus B2, were analysed for evidence of the virus. The plants and water were sampled at different times and virus was measured using quantitative RT-PCR and infectivity assay. In leaf samples, the lowest observed infective data were lower than the qRT-PCR detection limits, suggesting that free viral RNA or damaged viruses are eliminated rapidly while infectious particles remain stable for a longer time. The obtained data revealed that the leaves were contaminated at a water concentration of 4.11 ± 1 Log Most Probable Number/L (8.03 ± 1 Log GC/L) a concentration observed in contaminated untreated water of wastewater treatment plants. However, the absorption dynamics and whether the virus is inactive in the leaves still remains to be clarified. Nevertheless, this work has practical implications for risk management in using reclaimed water for agricultural use; when irrigated vegetables are destined for raw consumption, virological contamination in water sources should be evaluated. PMID:26193291

  16. Possible Internalization of an Enterovirus in Hydroponically Grown Lettuce

    PubMed Central

    Carducci, Annalaura; Caponi, Elisa; Ciurli, Adriana; Verani, Marco

    2015-01-01

    Several studies have shown that enteric viruses can be transferred onto the surface of vegetables and fruits through spray irrigation, but, recently, reports have suggested viral contamination of vegetables sub-irrigated with reused wastewater. Hydroponic cultures, used to grow ready to eat fresh lettuce, have also been used to study the possibility of viral absorption through roots. This study was conducted to assess a possible risk of viral contamination in lettuce from contaminated water. The leaves of lettuce plants grown in hydroponic cultures where the roots were exposed to water containing Coxsakievirus B2, were analysed for evidence of the virus. The plants and water were sampled at different times and virus was measured using quantitative RT-PCR and infectivity assay. In leaf samples, the lowest observed infective data were lower than the qRT-PCR detection limits, suggesting that free viral RNA or damaged viruses are eliminated rapidly while infectious particles remain stable for a longer time. The obtained data revealed that the leaves were contaminated at a water concentration of 4.11 ± 1 Log Most Probable Number/L (8.03 ± 1 Log GC/L) a concentration observed in contaminated untreated water of wastewater treatment plants. However, the absorption dynamics and whether the virus is inactive in the leaves still remains to be clarified. Nevertheless, this work has practical implications for risk management in using reclaimed water for agricultural use; when irrigated vegetables are destined for raw consumption, virological contamination in water sources should be evaluated. PMID:26193291

  17. Arsenic bioavailability in soils before and after soil washing: the use of Escherichia coli whole-cell bioreporters.

    PubMed

    Yoon, Youngdae; Kang, Yerin; Chae, Yooeun; Kim, Sunghoon; Lee, Youngshim; Jeong, Seung-Woo; An, Youn-Joo

    2016-02-01

    We investigated the quantification of bioavailable arsenic in contaminated soils and evaluation of soil-washing processes in the aspect of bioavailability using a novel bacterial bioreporter developed in present study. The whole-cell bioreporter (WCB) was genetically engineered by fusing the promoter of nik operon from Escherichia coli and green fluorescent protein as a sensing domain and reporter domain. Among eight well-known hazardous heavy metals and metalloid, this system responded specifically to arsenic, thereby inferring association of As(III) with NikR inhibits the repression. Moreover, the response was proportional to the concentration of As(III), thereby it was capable to determine the amount of bioavailable arsenic quantitatively in contaminated soils. The bioavailable portion of arsenic was 5.9 (3.46-10.96) and 0.9 (0.27-1.74) % of total from amended and site soils, respectively, suggesting the bioavailability of arsenic in soils was related to the soil properties and duration of aging. On the other hand, only 1.37 (0.21-2.97) % of total arsenic was extracted into soil solutions and 19.88 (11.86-28.27) % of arsenic in soil solution was bioavailable. This result showed that the soluble arsenic is not all bioavailable and most of bioavailable arsenic in soils is water non-extractable. In addition, the bioavailable arsenic was increased after soil-washing while total amount was decreased, thereby suggesting the soil-washing processes release arsenic associated with soil materials to be bioavailable. Therefore, it would be valuable to have a tool to assess bioavailability and the bioavailability should be taken into consideration for soil remediation plans. PMID:26411448

  18. Absolute oral bioavailability of ciprofloxacin.

    PubMed

    Drusano, G L; Standiford, H C; Plaisance, K; Forrest, A; Leslie, J; Caldwell, J

    1986-09-01

    We evaluated the absolute bioavailability of ciprofloxacin, a new quinoline carboxylic acid, in 12 healthy male volunteers. Doses of 200 mg were given to each of the volunteers in a randomized, crossover manner 1 week apart orally and as a 10-min intravenous infusion. Half-lives (mean +/- standard deviation) for the intravenous and oral administration arms were 4.2 +/- 0.77 and 4.11 +/- 0.74 h, respectively. The serum clearance rate averaged 28.5 +/- 4.7 liters/h per 1.73 m2 for the intravenous administration arm. The renal clearance rate accounted for approximately 60% of the corresponding serum clearance rate and was 16.9 +/- 3.0 liters/h per 1.73 m2 for the intravenous arm and 17.0 +/- 2.86 liters/h per 1.73 m2 for the oral administration arm. Absorption was rapid, with peak concentrations in serum occurring at 0.71 +/- 0.15 h. Bioavailability, defined as the ratio of the area under the curve from 0 h to infinity for the oral to the intravenous dose, was 69 +/- 7%. We conclude that ciprofloxacin is rapidly absorbed and reliably bioavailable in these healthy volunteers. Further studies with ciprofloxacin should be undertaken in target patient populations under actual clinical circumstances. PMID:3777908

  19. How-to-Do-It. Hydroponics and Aquaculture in the High School Classroom.

    ERIC Educational Resources Information Center

    Nicol, Ernest

    1990-01-01

    The construction of a hydroponic system for use in the classroom is described. Provided are construction details, a list of materials with approximate cost, a diagram of the setup, and a sample test. Several activities are suggested. (CW)

  20. ANALYSIS OF HYDROPONIC FERTILIZER MATRIXES FOR PERCHLORATE: COMPARISON OF ANALYTICAL TECHNIQUES

    EPA Science Inventory

    Seven retail hydroponic nitrate fertilizer products, two liquid and five solid, were comparatively analyzed for the perchlorate anion (ClO4-) by ion chromatography (IC) with suppressed conductivity detection, complexation electrospray ionization mass spectrometry (cESI-MS), norma...

  1. Uptake of 2,4,6-Trinitrotoluene (TNT) by Vetiver grass (Vetiviera ziznoides L.) -- Preliminary results from a hydroponic study

    NASA Astrophysics Data System (ADS)

    Shakya, K. M.; Sarkar, D.; Datta, R.; Makris, K.; Pachanoor, D.

    2006-05-01

    2,4,6-Trinitrotoluene(TNT) is a potent mutagen and a Group C human carcinogen that has been widely used to produce munitions and explosives. As a result, vast areas that have been previously used as military ranges, munition burning and open detonation sites have been heavily contaminated with TNT. Conventional remedial activities in such contaminated sites commonly rely on methods such as incineration, land filling and soil composting. Phytoremediation offers a cost-effective solution, utilizing plants to phytoextract TNT from the contaminated soil. We propose the use of vetiver grass (Vetiveria zizanoides) to remove TNT from such contaminated soils. Vetiver is a fast-growing and adaptive grass, enabling its use in TNT-contaminated sites in a wide variety of soil types and climate. We also hypothesized that TNT removal by vetiver grass will be enhanced by utilizing a chaotropic agent (urea) to alter rhizosphere/root hair chemical environment. The objectives of this preliminary hydroponic study were: i) to investigate the effectiveness of vetiver grass in removing TNT from solution, and ii) to evaluate the use of a common agrochemical (urea) in enhancing TNT removal by vetiver grass. Vetiver plants were grown in a hydroponic system with five different TNT concentrations (0, 5, 10, 25, and 50 mg TNT L-1) and three urea concentrations (0, 0.01 and 0.1%). A plant density of 10 g L-1 and three replicate vessels per treatment were used. Aliquots were collected at several time intervals up to 192 hour, and were analyzed for TNT with HPLC. Results showed that vetiver was able to remove TNT from hydroponic solutions. The overall magnitude and kinetics of TNT removal by vetiver grass was enhanced in the presence of urea. TNT removal kinetics depended on TNT and urea initial concentrations, suggestive of second-order kinetic reactions. Preliminary results are encouraging, but in need for verification using more detailed studies involving TNT-contaminated soils. Ongoing

  2. Bioavailability of valsartan oral dosage forms.

    PubMed

    Sunkara, Gangadhar; Bende, Girish; Mendonza, Anisha E; Solar-Yohay, Susan; Biswal, Shibadas; Neelakantham, Srikanth; Wagner, Robert; Flarakos, Jimmy; Zhang, Yiming; Jarugula, Venkateswar

    2014-03-01

    The oral bioavailability of valsartan from extemporaneous suspension and solution formulations were evaluated relative to tablet formulation in two separate open-label, randomized crossover studies in healthy adults. In both studies, the plasma concentrations of valsartan after oral administration were analyzed using validated liquid chromatography-tandem mass spectrometry (LC-MS/MS) methods, and the corresponding pharmacokinetic parameters were estimated using noncompartmental analysis. The peak plasma concentration (Cmax ) and area under the concentration time-curves (AUC(0-∞) ) of valsartan from the extemporaneous suspension were higher by 1.93- and 1.56-fold, respectively, relative to the tablet formulation (P < .001). The Cmax and AUC(0-∞) of valsartan from the oral solution were higher by 2.21- and 1.74-fold, respectively, relative to the tablet formulation (P < .001). These results indicate that both rate and extent of absorption of valsartan are higher in the two liquid dosage forms (extemporaneous suspension and solution formulations) relative to the solid oral dosage form (tablet formulation). PMID:27128457

  3. [Bioavailability of cadmium associated with oxides in sediment: effects of species of mineral, association form and aging on bioavailability].

    PubMed

    Wang, He; Jia, Yong-feng; Liu, Li; Wang, Shu-ying

    2009-10-15

    The bioavailability of heavy metals in sediments is largely controlled by their speciation. Effects of different Cd speciation associated with metal hydroxide on Cd bioavailability were studied. Iron and aluminum hydroxides were chosen as representatives of the oxides commonly present in sediments. In cultivar system, Hoagland solution was used as nutrition supply, and metal hydroxide associated with Cd as the only source of contamination and Phragmites australis was induced to study Cd bioaccumulation. After 13 d cultivation, Cd was uptaken and accumulated in P. australis, with different bioaccumulation from 9.1 to 37.8 mg x kg(-1) in root; and 0 to 10.0 mg x kg(-1) in shoot. Hereinto, the P. australis cultivated in Fe0.5Al0.5(OH)3 medium was found to have accumulated the largest amount of Cd in root, followed by those in Fe(OH)3 and aged Fe0.5Al0.5(OH)3, the lowest root concentration of Cd was observed in the plants cultivated in aged Fe(OH)3. Desorption order of Cd by organic acid was consistent with the Cd accumulation in P. australis. Thus, coprecipitation treatment decreases the bioavailability of Cd; association of aluminum hydroxide with Cd is poor due to its physicochemical property; aging treatment significantly restrict the accumulation of adsorbed Cd; desorption by organic acid verify the discrepancy in bioavailability of different speciation of Cd. PMID:19968130

  4. Comparison of Land, Water, and Energy Requirements of Lettuce Grown Using Hydroponic vs. Conventional Agricultural Methods.

    PubMed

    Barbosa, Guilherme Lages; Gadelha, Francisca Daiane Almeida; Kublik, Natalya; Proctor, Alan; Reichelm, Lucas; Weissinger, Emily; Wohlleb, Gregory M; Halden, Rolf U

    2015-06-01

    The land, water, and energy requirements of hydroponics were compared to those of conventional agriculture by example of lettuce production in Yuma, Arizona, USA. Data were obtained from crop budgets and governmental agricultural statistics, and contrasted with theoretical data for hydroponic lettuce production derived by using engineering equations populated with literature values. Yields of lettuce per greenhouse unit (815 m2) of 41 ± 6.1 kg/m2/y had water and energy demands of 20 ± 3.8 L/kg/y and 90,000 ± 11,000 kJ/kg/y (±standard deviation), respectively. In comparison, conventional production yielded 3.9 ± 0.21 kg/m2/y of produce, with water and energy demands of 250 ± 25 L/kg/y and 1100 ± 75 kJ/kg/y, respectively. Hydroponics offered 11 ± 1.7 times higher yields but required 82 ± 11 times more energy compared to conventionally produced lettuce. To the authors' knowledge, this is the first quantitative comparison of conventional and hydroponic produce production by example of lettuce grown in the southwestern United States. It identified energy availability as a major factor in assessing the sustainability of hydroponics, and it points to water-scarce settings offering an abundance of renewable energy (e.g., from solar, geothermal, or wind power) as particularly attractive regions for hydroponic agriculture. PMID:26086708

  5. Comparison of Land, Water, and Energy Requirements of Lettuce Grown Using Hydroponic vs. Conventional Agricultural Methods

    PubMed Central

    Lages Barbosa, Guilherme; Almeida Gadelha, Francisca Daiane; Kublik, Natalya; Proctor, Alan; Reichelm, Lucas; Weissinger, Emily; Wohlleb, Gregory M.; Halden, Rolf U.

    2015-01-01

    The land, water, and energy requirements of hydroponics were compared to those of conventional agriculture by example of lettuce production in Yuma, Arizona, USA. Data were obtained from crop budgets and governmental agricultural statistics, and contrasted with theoretical data for hydroponic lettuce production derived by using engineering equations populated with literature values. Yields of lettuce per greenhouse unit (815 m2) of 41 ± 6.1 kg/m2/y had water and energy demands of 20 ± 3.8 L/kg/y and 90,000 ± 11,000 kJ/kg/y (±standard deviation), respectively. In comparison, conventional production yielded 3.9 ± 0.21 kg/m2/y of produce, with water and energy demands of 250 ± 25 L/kg/y and 1100 ± 75 kJ/kg/y, respectively. Hydroponics offered 11 ± 1.7 times higher yields but required 82 ± 11 times more energy compared to conventionally produced lettuce. To the authors’ knowledge, this is the first quantitative comparison of conventional and hydroponic produce production by example of lettuce grown in the southwestern United States. It identified energy availability as a major factor in assessing the sustainability of hydroponics, and it points to water-scarce settings offering an abundance of renewable energy (e.g., from solar, geothermal, or wind power) as particularly attractive regions for hydroponic agriculture. PMID:26086708

  6. Selection and hydroponic growth of potato cultivars for bioregenerative life support systems

    NASA Astrophysics Data System (ADS)

    Molders, K.; Quinet, M.; Decat, J.; Secco, B.; Dulière, E.; Pieters, S.; van der Kooij, T.; Lutts, S.; Van Der Straeten, D.

    2012-07-01

    As part of the ESA-funded MELiSSA program, Ghent University and the Université catholique de Louvain investigated the suitability, growth and development of four potato cultivars in hydroponic culture under controlled conditions with the aim to incorporate such cultivation system in an Environmental Control and Life Support System (ECLSS). Potato plants can fulfill three major functions in an ECLSS in space missions: (a) fixation of CO2 and production of O2, (b) production of tubers for human nutrition and (c) production of clean water after condensation of the water vapor released from the plants by transpiration. Four cultivars (Annabelle, Bintje, Desiree and Innovator) were selected and grown hydroponically in nutrient film technique (NFT) gullies in a growth chamber under controlled conditions. The plant growth parameters, tuber harvest parameters and results of tuber nutritional analysis of the four cultivars were compared. The four potato cultivars grew well and all produced tubers. The growth period lasted 127 days for all cultivars except for Desiree which needed 145 days. Annabelle (1.45 kg/m2) and Bintje (1.355 kg/m2) were the best performing of the four cultivars. They also produced two times more tubers than Desiree and Innovator. Innovator produced the biggest tubers (20.95 g/tuber) and Desiree the smallest (7.67 g/tuber). The size of Annabelle and Bintje potatoes were intermediate. Bintje plants produced the highest total biomass in term of DW. The highest non-edible biomass was produced by Desiree, which showed both the highest shoot and root DW. The manual length and width measurements were also used to predict the total tuber mass. The energy values of the tubers remained in the range of the 2010 USDA and Souci-Fachmann-Kraut food composition databases. The amount of Ca determined was slightly reduced compared to the USDA value, but close to the Souci-Fachmann-Kraut value. The concentration of Cu, Zn and P were high compared to both databases

  7. Stabilization of pH in solid-matrix hydroponic systems

    NASA Technical Reports Server (NTRS)

    Frick, J.; Mitchell, C. A.

    1993-01-01

    2-[N-morpholino]ethanesulfonic acid (MES) buffer or Amberlite DP-1 (cation-exchange resin beads) were used to stabilize substrate pH of passive-wicking, solid-matrix hydroponic systems in which small canopies of Brassica napus L. (CrGC 5-2, genome : ACaacc) were grown to maturity. Two concentrations of MES (5 or 10 mM) were included in Hoagland 1 nutrient solution. Alternatively, resin beads were incorporated into the 2 vermiculite : 1 perlite (v/v) growth medium at 6% or 12% of total substrate volume. Both strategies stabilized pH without toxic side effects on plants. Average seed yield rates for all four pH stabilization treatments (13.3 to 16.9 g m-2 day-1) were about double that of the control (8.2 g m-2 day-1), for which there was no attempt to buffer substrate pH. Both the highest canopy seed yield rate (16.9 g m-2 day-1) and the highest shoot harvest index (19.5%) occurred with the 6% resin bead treatment, even though the 10 mM MES and 12% bead treatments maintained pH within the narrowest limits. The pH stabilization methods tested did not significantly affect seed oil and protein contents.

  8. Hydroponics Database and Handbook for the Advanced Life Support Test Bed

    NASA Technical Reports Server (NTRS)

    Nash, Allen J.

    1999-01-01

    During the summer 1998, I did student assistance to Dr. Daniel J. Barta, chief plant growth expert at Johnson Space Center - NASA. We established the preliminary stages of a hydroponic crop growth database for the Advanced Life Support Systems Integration Test Bed, otherwise referred to as BIO-Plex (Biological Planetary Life Support Systems Test Complex). The database summarizes information from published technical papers by plant growth experts, and it includes bibliographical, environmental and harvest information based on plant growth under varying environmental conditions. I collected 84 lettuce entries, 14 soybean, 49 sweet potato, 16 wheat, 237 white potato, and 26 mix crop entries. The list will grow with the publication of new research. This database will be integrated with a search and systems analysis computer program that will cross-reference multiple parameters to determine optimum edible yield under varying parameters. Also, we have made preliminary effort to put together a crop handbook for BIO-Plex plant growth management. It will be a collection of information obtained from experts who provided recommendations on a particular crop's growing conditions. It includes bibliographic, environmental, nutrient solution, potential yield, harvest nutritional, and propagation procedure information. This handbook will stand as the baseline growth conditions for the first set of experiments in the BIO-Plex facility.

  9. Hydroponic screening of black locust families for heavy metal tolerance and accumulation.

    PubMed

    Župunski, Milan; Borišev, Milan; Orlović, Saša; Arsenov, Danijela; Nikolić, Nataša; Pilipović, Andrej; Pajević, Slobodanka

    2016-01-01

    Present work examines phytoextraction potential of four black locust families (half-sibs 54, 56, 115, and 135) grown hydroponically. Plants were treated with 6 ppm of cadmium (Cd), 100 ppm of nickel (Ni), and 40 ppm of lead (Pb) added in Hoagland nutrient solution, accompanying with simultaneously applied all three metals. Responses to metals exposure among families were different, ranging from severe to slight reduction of root and shoot biomass production of treated plants. Calculated tolerance indices are indicating tested families as highly tolerant (Ti > 60). Family 135 had the lowest tolerance index, pointing that it was highly susceptible to applied metals. Comparing photosynthetic activities of tested families it has been noticed that they were highly sensitive to stress induced by heavy metals. Net photosynthetic rate of nickel treated plants was the most affected by applied concentration. Cadmium and nickel concentrations in stems and leaves of black locust families exceeded 100 mg Cd kg(-1) and 1000 mg Ni kg(-1), in both single and multipollution context. On the contrary, accumulation of lead in above ground biomass was highly affected by multipollution treatment. Tf and BCF significantly varied between investigated treatments and families of black locust. Concerning obtained results of heavy metals accumulation and tolerance of black locust families can be concluded that tested families might be a promising tool for phytoextraction purposes, but it takes to be further confirmed in field trials. PMID:26332106

  10. Use of hydroponics culture to assess nutrient supply by treated wastewater.

    PubMed

    Adrover, Maria; Moyà, Gabriel; Vadell, Jaume

    2013-09-30

    The use of treated wastewater for irrigation is increasing, especially in those areas where water resources are limited. Treated wastewaters contain nutrients that are useful for plant growth and help to reduce fertilizers needs. Nutrient content of these waters depends on the treatment system. Nutrient supply by a treated wastewater from a conventional treatment plant (CWW) and a lagooned wastewater from the campus of the University of Balearic Islands (LWW) was tested in an experiment in hydroponics conditions. Half-strength Hoagland nutrient solution (HNS) was used as a control. Barley (Hordeum vulgare L.) seedlings were grown in 4 L containers filled with the three types of water. Four weeks after planting, barley was harvested and root and shoot biomass was measured. N, P, K, Ca, Mg, Na and Fe contents were determined in both tissues and heavy metal concentrations were analysed in shoots. N, P and K concentrations were lower in LWW than in CWW, while HNS had the highest nutrient concentration. Dry weight barley production was reduced in CWW and LWW treatments to 49% and 17%, respectively, comparing to HNS. However, to a lesser extent, reduction was found in shoot and root N content. Treated wastewater increased Na content in shoots and roots of barley and Ca and Cr content in shoots. However, heavy metals content was lower than toxic levels in all the cases. Although treated wastewater is an interesting water resource, additional fertilization is needed to maintain a high productivity in barley seedlings. PMID:23708198

  11. Stabilization of pH in solid-matrix hydroponic systems.

    PubMed

    Frick, J; Mitchell, C A

    1993-10-01

    2-[N-morpholino]ethanesulfonic acid (MES) buffer or Amberlite DP-1 (cation-exchange resin beads) were used to stabilize substrate pH of passive-wicking, solid-matrix hydroponic systems in which small canopies of Brassica napus L. (CrGC 5-2, genome : ACaacc) were grown to maturity. Two concentrations of MES (5 or 10 mM) were included in Hoagland 1 nutrient solution. Alternatively, resin beads were incorporated into the 2 vermiculite : 1 perlite (v/v) growth medium at 6% or 12% of total substrate volume. Both strategies stabilized pH without toxic side effects on plants. Average seed yield rates for all four pH stabilization treatments (13.3 to 16.9 g m-2 day-1) were about double that of the control (8.2 g m-2 day-1), for which there was no attempt to buffer substrate pH. Both the highest canopy seed yield rate (16.9 g m-2 day-1) and the highest shoot harvest index (19.5%) occurred with the 6% resin bead treatment, even though the 10 mM MES and 12% bead treatments maintained pH within the narrowest limits. The pH stabilization methods tested did not significantly affect seed oil and protein contents. PMID:11537992

  12. Dissolved organic matter kinetically controls mercury bioavailability to bacteria.

    PubMed

    Chiasson-Gould, Sophie A; Blais, Jules M; Poulain, Alexandre J

    2014-03-18

    Predicting the bioavailability of inorganic mercury (Hg) to bacteria that produce the potent bioaccumulative neurotoxin monomethylmercury remains one of the greatest challenges in predicting the environmental fate and transport of Hg. Dissolved organic matter (DOM) affects mercury methylation due to its influence on cell physiology (as a potential nutrient) and its influence on Hg(II) speciation in solution (as a complexing agent), therefore controlling Hg bioavailability. We assessed the role of DOM on Hg(II) bioavailability to a gram-negative bacterium bioreporter under oxic pseudo- and nonequilibrium conditions, using defined media and field samples spanning a wide range of DOM levels. Our results showed that Hg(II) was considerably more bioavailable under nonequilibrium conditions than when DOM was absent or when Hg(II) and DOM had reached pseudoequilibrium (24 h) prior to cell exposure. Under these enhanced uptake conditions, Hg(II) bioavailability followed a bell shaped curve as DOM concentrations increased, both for defined media and natural water samples, consistent with bioaccumulation results in a companion paper (this issue) observed for amphipods. Experiments also suggest that DOM may not only provide shuttle molecules facilitating Hg uptake, but also alter cell wall properties to facilitate the first steps toward Hg(II) internalization. We propose the existence of a short-lived yet critical time window (<24 h) during which DOM facilitates the entry of newly deposited Hg(II) into aquatic food webs, suggesting that the bulk of mercury incorporation in aquatic food webs would occur within hours following its deposition from the atmosphere. PMID:24524696

  13. Bacterial siderophores efficiently provide iron to iron-starved tomato plants in hydroponics culture.

    PubMed

    Radzki, W; Gutierrez Mañero, F J; Algar, E; Lucas García, J A; García-Villaraco, A; Ramos Solano, B

    2013-09-01

    Iron is one of the essential elements for a proper plant development. Providing plants with an accessible form of iron is crucial when it is scant or unavailable in soils. Chemical chelates are the only current alternative and are highly stable in soils, therefore, posing a threat to drinking water. The aim of this investigation was to quantify siderophores produced by two bacterial strains and to determine if these bacterial siderophores would palliate chlorotic symptoms of iron-starved tomato plants. For this purpose, siderophore production in MM9 medium by two selected bacterial strains was quantified, and the best was used for biological assay. Bacterial culture media free of bacteria (S) and with bacterial cells (BS), both supplemented with Fe were delivered to 12-week-old plants grown under iron starvation in hydroponic conditions; controls with full Hoagland solution, iron-free Hoagland solution and water were also conducted. Treatments were applied twice along the experiment, with a week in between. At harvest, plant yield, chlorophyll content and nutritional status in leaves were measured. Both the bacterial siderophore treatments significantly increased plant yield, chlorophyll and iron content over the positive controls with full Hoagland solution, indicating that siderophores are effective in providing Fe to the plant, either with or without the presence of bacteria. In summary, siderophores from strain Chryseobacterium C138 are effective in supplying Fe to iron-starved tomato plants by the roots, either with or without the presence of bacteria. Based on the amount of siderophores produced, an effective and economically feasible organic Fe chelator could be developed. PMID:23812968

  14. Fractionation mechanisms of rare earth elements (REEs) in hydroponic wheat: an application for metal accumulation by plants.

    PubMed

    Ding, Shiming; Liang, Tao; Zhang, Chaosheng; Huang, Zechun; Xie, Yaning; Chen, Tongbin

    2006-04-15

    Fractionations of rare earth elements (REEs) in wheat (Triticum aestivum L.) were observed through application of exogenous mixed REEs under hydroponic conditions. Middle REE (MREE), light REE (LREE), and heavy REE (HREE) enrichments were found in roots, stems, and leaves, respectively, accompanied by the tetrad effect (an effect that can cause a split of REE patterns into four consecutive segments) in these organs. Investigations into REE speciation in roots and in the xylem sap with X-ray absorption spectroscopy (XAS) and nanometer-sized TiO2 adsorption techniques, associated with other controlled experiments, demonstrated that REE fractionations in wheat were caused by the combined effects of chemical precipitation, cell wall absorption, and solution complexation by organic ligands in the xylem vessels. REE fractionations in wheat, which were derived from the small differences of chemical properties across REE series, may reflect a sensitive internal chemical environment that influences plant accumulation for REEs and their analogues actinide radionuclides. PMID:16683609

  15. Cilioprotists as biological indicators for estimating the efficiency of using Gravel Bed Hydroponics System in domestic wastewater treatment.

    PubMed

    El-Serehy, Hamed A; Bahgat, Magdy M; Al-Rasheid, Khaled; Al-Misned, Fahad; Mortuza, Golam; Shafik, Hesham

    2014-07-01

    Interest has increased over the last several years in using different methods for treating sewage. The rapid population growth in developing countries (Egypt, for example, with a population of more than 87 millions) has created significant sewage disposal problems. There is therefore a growing need for sewage treatment solutions with low energy requirements and using indigenous materials and skills. Gravel Bed Hydroponics (GBH) as a constructed wetland system for sewage treatment has been proved effective for sewage treatment in several Egyptian villages. The system provided an excellent environment for a wide range of species of ciliates (23 species) and these organisms were potentially very useful as biological indicators for various saprobic conditions. Moreover, the ciliates provided excellent means for estimating the efficiency of the system for sewage purification. Results affirmed the ability of this system to produce high quality effluent with sufficient microbial reduction to enable the production of irrigation quality water. PMID:24955010

  16. Cilioprotists as biological indicators for estimating the efficiency of using Gravel Bed Hydroponics System in domestic wastewater treatment

    PubMed Central

    El-Serehy, Hamed A.; Bahgat, Magdy M.; Al-Rasheid, Khaled; Al-Misned, Fahad; Mortuza, Golam; Shafik, Hesham

    2013-01-01

    Interest has increased over the last several years in using different methods for treating sewage. The rapid population growth in developing countries (Egypt, for example, with a population of more than 87 millions) has created significant sewage disposal problems. There is therefore a growing need for sewage treatment solutions with low energy requirements and using indigenous materials and skills. Gravel Bed Hydroponics (GBH) as a constructed wetland system for sewage treatment has been proved effective for sewage treatment in several Egyptian villages. The system provided an excellent environment for a wide range of species of ciliates (23 species) and these organisms were potentially very useful as biological indicators for various saprobic conditions. Moreover, the ciliates provided excellent means for estimating the efficiency of the system for sewage purification. Results affirmed the ability of this system to produce high quality effluent with sufficient microbial reduction to enable the production of irrigation quality water. PMID:24955010

  17. Preliminary investigations of the rhizosphere nature of hydroponically grown lettuces

    NASA Astrophysics Data System (ADS)

    Antunes, Inês; Paille, Christel; Lasseur, Christophe

    Due to capabilities of current launchers, future manned exploration beyond the Earth orbit will imply long journeys and extended stays on planet surfaces. For this reason, it is of a great importance to develop a Regenerative Life Support System that enables the crew to be, to a very large extent, metabolic consumables self-sufficient. In this context, the European Space Agency, associated with a scientific and engineering con-sortium, initiated in 1989 the Micro-Ecological Life Support System Alternative (MELiSSA) project. This concept, inspired on a terrestrial ecosystem (i.e. a lake), comprises five intercon-nected compartments inhabited by micro-organisms and higher-plants aiming to produce food, fresh water, and oxygen from organic waste, carbon dioxide, and minerals. Given the important role of the higher-plant compartment for the consumption of carbon dioxide and the production of oxygen, potable water, and food, it was decided to study the microbial communities present in the root zone of the plants (i.e. the rhizosphere), and their synergistic and antagonistic influences in the plant growth. This understanding is important for later investigations concerning the technology involved in the higher plant compartment, since the final goal is to integrate this compartment inside the MELiSSA loop and to guarantee a healthy and controlled environment for the plants to grow under reduced-gravity conditions. To perform a preliminary assessment of the microbial populations of the root zone, lettuces were grown in a hydroponic system and their growth was characterized in terms of nutrient uptake, plant diameter, and plant wet and dry weights. In parallel, the microbial population, bacteria and fungi, present in the hydroponic medium and also inside and outside the roots were analyzed in terms of quantity and nature. The goal of this presentation is to give a preliminary review in the plant root zone of the micro-organisms communities and as well their proportions

  18. Bioavailability of xenobiotics in the soil environment.

    PubMed

    Katayama, Arata; Bhula, Raj; Burns, G Richard; Carazo, Elizabeth; Felsot, Allan; Hamilton, Denis; Harris, Caroline; Kim, Yong-Hwa; Kleter, Gijs; Koedel, Werner; Linders, Jan; Peijnenburg, J G M Willie; Sabljic, Aleksandar; Stephenson, R Gerald; Racke, D Kenneth; Rubin, Baruch; Tanaka, Keiji; Unsworth, John; Wauchope, R Donald

    2010-01-01

    It is often presumed that all chemicals in soil are available to microorganisms, plant roots, and soil fauna via dermal exposure. Subsequent bioaccumulation through the food chain may then result in exposure to higher organisms. Using the presumption of total availability, national governments reduce environmental threshold levels of regulated chemicals by increasing guideline safety margins. However, evidence shows that chemical residues in the soil environment are not always bioavailable. Hence, actual chemical exposure levels of biota are much less than concentrations present in soil would suggest. Because "bioavailability" conveys meaning that combines implications of chemical sol persistency, efficacy, and toxicity, insights on the magnitude of a chemicals soil bioavailability is valuable. however, soil bioavailability of chemicals is a complex topic, and is affected by chemical properties, soil properties, species exposed, climate, and interaction processes. In this review, the state-of-art scientific basis for bioavailability is addressed. Key points covered include: definition, factors affecting bioavailability, equations governing key transport and distributive kinetics, and primary methods for estimating bioavailability. Primary transport mechanisms in living organisms, critical to an understanding of bioavailability, also presage the review. Transport of lipophilic chemicals occurs mainly by passive diffusion for all microorganisms, plants, and soil fauna. Therefore, the distribution of a chemical between organisms and soil (bioavailable proportion) follows partition equilibrium theory. However, a chemical's bioavailability does not always follow partition equilibrium theory because of other interactions with soil, such as soil sorption, hysteretic desorption, effects of surfactants in pore water, formation of "bound residue", etc. Bioassays for estimating chemical bioavailability have been introduced with several targeted endpoints: microbial

  19. A small scale hydroponics wastewater treatment system under Swedish conditions.

    PubMed

    Norström, A; Larsdotter, K; Gumaelius, L; la Cour Jansen, J; Dalhammar, G

    2003-01-01

    A treatment plant using conventional biological treatment combined with hydroponics and microalgae is constructed in a greenhouse in the area of Stockholm, Sweden. The treatment plant is built for research purposes and presently treats 0.559 m3 of domestic wastewater from the surrounding area per day. The system uses anoxic pre-denitrification followed by aerobic tanks for nitrification and plant growth. A microalgal step further reduces phosphorus, and a final sand filter polishes the water. During a three week period in July 2002 the treatment capacity of this system was evaluated with respect to removal of organic matter, phosphorus and nitrogen. 90% COD removal was obtained early in the system. Nitrification and denitrification was well established with total nitrogen reduction of 72%. Phosphorus was removed by 47% in the process. However, higher phosphorus removal values are expected as the microalgal step will be further developed. The results show that acceptable treatment can be achieved using this kind of system. Further optimisation of the system will lead to clean water as well as valuable plants to be harvested from the nutrient rich wastewater. PMID:14753532

  20. Hydroponic root mats for wastewater treatment-a review.

    PubMed

    Chen, Zhongbing; Cuervo, Diego Paredes; Müller, Jochen A; Wiessner, Arndt; Köser, Heinz; Vymazal, Jan; Kästner, Matthias; Kuschk, Peter

    2016-08-01

    Hydroponic root mats (HRMs) are ecotechnological wastewater treatment systems where aquatic vegetation forms buoyant filters by their dense interwoven roots and rhizomes, sometimes supported by rafts or other floating materials. A preferential hydraulic flow is created in the water zone between the plant root mat and the bottom of the treatment system. When the mat touches the bottom of the water body, such systems can also function as HRM filter; i.e. the hydraulic flow passes directly through the root zone. HRMs have been used for the treatment of various types of polluted water, including domestic wastewater; agricultural effluents; and polluted river, lake, stormwater and groundwater and even acid mine drainage. This article provides an overview on the concept of applying floating HRM and non-floating HRM filters for wastewater treatment. Exemplary performance data are presented, and the advantages and disadvantages of this technology are discussed in comparison to those of ponds, free-floating plant and soil-based constructed wetlands. Finally, suggestions are provided on the preferred scope of application of HRMs. PMID:27164889

  1. Effects of silicon and copper on bamboo grown hydroponically.

    PubMed

    Collin, Blanche; Doelsch, Emmanuel; Keller, Catherine; Panfili, Frédéric; Meunier, Jean-Dominique

    2013-09-01

    Due to its high growth rate and biomass production, bamboo has recently been proven to be useful in wastewater treatment. Bamboo accumulates high silicon (Si) levels in its tissues, which may improve its development and tolerance to metal toxicity. This study investigates the effect of Si supplementation on bamboo growth and copper (Cu) sensitivity. An 8-month hydroponic culture of bamboo Gigantocloa sp. "Malay Dwarf " was performed. The bamboo plants were first submitted to a range of Si supplementation (0-1.5 mM). After 6 months, a potentially toxic Cu concentration of 1.5 μM Cu(2+) was added. Contrary to many studies on other plants, bamboo growth did not depend on Si levels even though it absorbed Si up to 218 mg g(-1) in leaves. The absorption of Cu by bamboo plants was not altered by the Si supplementation; Cu accumulated mainly in roots (131 mg kg(-1)), but was also found in leaves (16.6 mg kg(-1)) and stems (9.8 mg kg(-1)). Copper addition did not induce any toxicity symptoms. The different Cu and Si absorption mechanisms may partially explain why Si did not influence Cu repartition and concentration in bamboo. Given the high biomass and its absorption capacity, bamboo could potentially tolerate and accumulate high Cu concentrations making this plant useful for wastewater treatment. PMID:23608981

  2. Bioavailability and biodistribution of nanodelivered lutein

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The aim of the study was to evaluate the ability of poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NP) to enhance lutein bioavailability. The bioavailability of free lutein and PLGA-NP lutein in rats was assessed by determining plasma pharmacokinetics and deposition in selected tissues. Lutein ...

  3. ZnCl 2- and NH 4Cl-hydroponics gel electrolytes for zinc-carbon batteries

    NASA Astrophysics Data System (ADS)

    Khalid, N. H.; Ismail, Y. M. Baba; Mohamad, A. A.

    Absorbency testing is used to determine the percentage of ZnCl 2 or NH 4Cl solution absorbed by a hydroponics gel (HPG). It is found that the absorbency of ZnCl 2 or NH 4Cl solution decreases with increasing solution concentration. The conductivity of ZnCl 2- and NH 4Cl-HPG electrolytes is dependent on the solution concentration. A mixture of salt solution with HPG yields excellent gel polymer electrolytes with conductivities of 0.026 and 0.104 S cm -1 at 3 M ZnCl 2 and 7 M NH 4Cl, respectively. These gel electrolytes are then used to produce zinc-carbon cells. The fabricated cells give capacities of 8.8 and 10.0 mAh, have an internal resistance of 25.4 and 19.8 Ω, a maximum power density of 12.7 and 12.2 mW cm -2, and a short-circuit current density of 29.1 and 33.9 mA cm -2 for ZnCl 2- and NH 4Cl-HPG electrolytes, respectively.

  4. The Nutraceutical Bioavailability Classification Scheme: Classifying Nutraceuticals According to Factors Limiting their Oral Bioavailability.

    PubMed

    McClements, David Julian; Li, Fang; Xiao, Hang

    2015-01-01

    The oral bioavailability of a health-promoting dietary component (nutraceutical) may be limited by various physicochemical and physiological phenomena: liberation from food matrices, solubility in gastrointestinal fluids, interaction with gastrointestinal components, chemical degradation or metabolism, and epithelium cell permeability. Nutraceutical bioavailability can therefore be improved by designing food matrices that control their bioaccessibility (B*), absorption (A*), and transformation (T*) within the gastrointestinal tract (GIT). This article reviews the major factors influencing the gastrointestinal fate of nutraceuticals, and then uses this information to develop a new scheme to classify the major factors limiting nutraceutical bioavailability: the nutraceutical bioavailability classification scheme (NuBACS). This new scheme is analogous to the biopharmaceutical classification scheme (BCS) used by the pharmaceutical industry to classify drug bioavailability, but it contains additional factors important for understanding nutraceutical bioavailability in foods. The article also highlights potential strategies for increasing the oral bioavailability of nutraceuticals based on their NuBACS designation (B*A*T*). PMID:25705933

  5. Probing Phosphorus Efficient Low Phytic Acid Content Soybean Genotypes with Phosphorus Starvation in Hydroponics Growth System.

    PubMed

    Kumar, Varun; Singh, Tiratha Raj; Hada, Alkesh; Jolly, Monica; Ganapathi, Andy; Sachdev, Archana

    2015-10-01

    Phosphorus is an essential nutrient required for soybean growth but is bound in phytic acid which causes negative effects on both the environment as well as the animal nutrition. Lowering of phytic acid levels is associated with reduced agronomic characteristics, and relatively little information is available on the response of soybean plants to phosphorus (P) starvation. In this study, we evaluated the effects of different P starvation concentrations on the phytic acid content, growth, and yield of seven mutant genotypes along with the unirradiated control, JS-335, in a hydroponics growth system. The low phytic acid containing mutant genotypes, IR-JS-101, IR-DS-118, and IR-V-101, showed a relatively high growth rate in low P concentration containing nutrient solution (2 μM), whereas the high P concentration (50 μM) favored the growth of IR-DS-111 and IR-DS-115 mutant genotypes containing moderate phytate levels. The mutant genotypes with high phytic acid content, IR-DS-122, IR-DS-114, and JS-335, responded well under P starvation and did not have any significant effect on the growth and yield of plants. Moreover, the reduction of P concentration in nutrient solution from 50 to 2 μM also reduced the phytic acid content in the seeds of all the soybean genotypes under study. The desirable agronomic performance of low phytic acid containing mutant genotype IR-DS-118 reported in this study suggested it to be a P-efficient genotype which could be considered for agricultural practices under P limiting soils. PMID:26239443

  6. Lead phytotoxicity in soils and nutrient solutions is related to lead induced phosphorus deficiency.

    PubMed

    Cheyns, Karlien; Peeters, Sofie; Delcourt, Dorien; Smolders, Erik

    2012-05-01

    This study was set up to relate lead (Pb) bioavailability with its toxicity to plants in soils. Tomato and barley seedlings were grown in six different PbCl(2) spiked soils (pH: 4.7-7.4; eCEC: 4.2-41.7 cmol(c)/kg). Soils were leached and pH corrected after spiking to exclude confounding factors. Plant growth was halved at 1600-6500 mg Pb/kg soil for tomato and at 1900-8300 mg Pb/kg soil for barley. These soil Pb threshold were unrelated to soil pH, organic carbon, texture or eCEC and neither soil solution Pb nor Pb(2+) ion activity adequately explained Pb toxicity among soils. Shoot phosphorus (P) concentrations significantly decreased with increasing soil Pb concentrations. Tomato grown in hydroponics at either varying P supply or at increasing Pb (equal initial P) illustrated that shoot P explained growth response in both scenarios. The results suggest that Pb toxicity is partially related to Pb induced P deficiency, likely due to lead phosphate precipitation. PMID:22377902

  7. Microemulsion Drug Delivery System: For Bioavailability Enhancement of Ampelopsin

    PubMed Central

    Solanki, Shailendra Singh; Sarkar, Brajesh; Dhanwani, Rakesh Kumar

    2012-01-01

    Ampelopsin, one of the most common flavonoids, reported to possess numerous pharmacological activities and shows poor aqueous solubility. The purpose of this study was to enhance the dissolution rate and bioavailability of this drug by developing a novel delivery system that is microemulsion (ME) and to study the effect of microemulsion (ME) on the oral bioavailability of ampelopsin. Capmul MCM-based ME formulation with Cremophor EL as surfactant and Transcutol as cosurfactant was developed for oral delivery of ampelopsin. Optimised ME was evaluated for its transparency, viscosity, percentage assay and so forth. Solubilisation capacity of the ME system was also determined. The prepared ME was compared with the pure drug solution and commercially available tablet for in vitro drug release. The optimised ME formulation containing ampelopsin, Capmul MCM (5.5%), Cremophor EL (25%), Transcutol P (8.5%), and distilled water showed higher in vitro drug release, as compared to plain drug suspension and the suspension of commercially available tablet. These results demonstrate the potential use of ME for improving the bioavailability of poor water soluble compounds, such as ampelopsin. PMID:22830055

  8. Pharmacokinetics and relative bioavailability of oral theophylline capsules.

    PubMed

    Lesko, L J; Canada, A T; Eastwood, G; Walker, D; Brousseau, D R

    1979-11-01

    The oral bioavailability of liquid-filled theophylline capsules relative to a nonalcoholic aminophylline solution was determined in normal volunteers. In addition, theophylline absorption and elimination kinetics were reexamined. There were no statistically significant differences between the bioavailability of capsules and liquid as measured by the area under the curve (AUC) from time 0 leads to infinity (p greater than 0.05). The bioavailability parameters of Cmax, tmax, and AUC were determined from actual serum theophylline concentration-time data and from a nonlinear least-squares fit of the serum concentration-time data. Theophylline absorption from the capsules was noticeably faster than from the liquid in most subjects, although the differences in absorption rates were not significantly different (p greater than 0.05). The determined apparent volume of distribution, elimination half-life, and plasma clearance of theophylline were similar to values reported by other investigators. Marked inter- and intraindividual variations in the elimination half-life were noted. PMID:583162

  9. Understanding Water-Stress Responses in Soybean Using Hydroponics System-A Systems Biology Perspective.

    PubMed

    Tripathi, Prateek; Rabara, Roel C; Shulaev, Vladimir; Shen, Qingxi J; Rushton, Paul J

    2015-01-01

    The deleterious changes in environmental conditions such as water stress bring physiological and biochemical changes in plants, which results in crop loss. Thus, combating water stress is important for crop improvement to manage the needs of growing population. Utilization of hydroponics system in growing plants is questionable to some researchers, as it does not represent an actual field condition. However, trying to address a complex problem like water stress we have to utilize a simpler growing condition like the hydroponics system wherein every input given to the plants can be controlled. With the advent of high-throughput technologies, it is still challenging to address all levels of the genetic machinery whether a gene, protein, metabolite, and promoter. Thus, using a system of reduced complexity like hydroponics can certainly direct us toward the right candidates, if not completely help us to resolve the issue. PMID:26734044

  10. Computer-operated analytical platform for the determination of nutrients in hydroponic systems.

    PubMed

    Rius-Ruiz, F Xavier; Andrade, Francisco J; Riu, Jordi; Rius, F Xavier

    2014-03-15

    Hydroponics is a water, energy, space, and cost efficient system for growing plants in constrained spaces or land exhausted areas. Precise control of hydroponic nutrients is essential for growing healthy plants and producing high yields. In this article we report for the first time on a new computer-operated analytical platform which can be readily used for the determination of essential nutrients in hydroponic growing systems. The liquid-handling system uses inexpensive components (i.e., peristaltic pump and solenoid valves), which are discretely computer-operated to automatically condition, calibrate and clean a multi-probe of solid-contact ion-selective electrodes (ISEs). These ISEs, which are based on carbon nanotubes, offer high portability, robustness and easy maintenance and storage. With this new computer-operated analytical platform we performed automatic measurements of K(+), Ca(2+), NO3(-) and Cl(-) during tomato plants growth in order to assure optimal nutritional uptake and tomato production. PMID:24206690

  11. A hydroponic system for growing gnotobiotic vs. sterile plants to study phytoremediation processes.

    PubMed

    Kurzbaum, E; Kirzhner, F; Armon, R

    2014-01-01

    In some phytoremediation studies it is desirable to separate and define the specific contribution of plants and root-colonizing bacteria towards contaminant removal. Separating the influence of plants and associated bacteria is a difficult task for soil root environments. Growing plants hydroponically provides more control over the biological factors in contaminant removal. In this study, a hydroponic system was designed to evaluate the role of sterile plant roots, rhizodeposition, and root-associated bacteria in the removal of a model contaminant, phenol. A strain of Pseudomonas pseudoalcaligenes that grows on phenol was inoculated onto plant roots. The introduced biofilm persisted in the root zone and promoted phenol removal over non-augmented controls. These findings indicate that this hydroponic system can be a valuable tool for phytoremediation studies that investigate the effects of biotic and abiotic factors on pollution remediation. PMID:24912223

  12. Understanding Water-Stress Responses in Soybean Using Hydroponics System—A Systems Biology Perspective

    PubMed Central

    Tripathi, Prateek; Rabara, Roel C.; Shulaev, Vladimir; Shen, Qingxi J.; Rushton, Paul J.

    2015-01-01

    The deleterious changes in environmental conditions such as water stress bring physiological and biochemical changes in plants, which results in crop loss. Thus, combating water stress is important for crop improvement to manage the needs of growing population. Utilization of hydroponics system in growing plants is questionable to some researchers, as it does not represent an actual field condition. However, trying to address a complex problem like water stress we have to utilize a simpler growing condition like the hydroponics system wherein every input given to the plants can be controlled. With the advent of high-throughput technologies, it is still challenging to address all levels of the genetic machinery whether a gene, protein, metabolite, and promoter. Thus, using a system of reduced complexity like hydroponics can certainly direct us toward the right candidates, if not completely help us to resolve the issue. PMID:26734044

  13. Automated Liquid-Level Control of a Nutrient Reservoir for a Hydroponic System

    NASA Technical Reports Server (NTRS)

    Smith, Boris; Asumadu, Johnson A.; Dogan, Numan S.

    1997-01-01

    A microprocessor-based system for control of the liquid level of a nutrient reservoir for a plant hydroponic growing system has been developed. The system uses an ultrasonic transducer to sense the liquid level or height. A National Instruments' Multifunction Analog and Digital Input/Output PC Kit includes NI-DAQ DOS/Windows driver software for an IBM 486 personal computer. A Labview Full Development system for Windows is the graphical programming system being used. The system allows liquid level control to within 0.1 cm for all levels tried between 8 and 36 cm in the hydroponic system application. The detailed algorithms have been developed and a fully automated microprocessor based nutrient replenishment system has been described for this hydroponic system.

  14. A corneal perfusion device for estimating ocular bioavailability in vitro.

    PubMed

    Richman, J B; Tang-Liu, D D

    1990-02-01

    An in vitro method for investigating drug penetration across the cornea from acute doses has been developed. The donor (epithelial or tear) side of a corneal chamber similar to those used by Edelhauser and co-workers was modified with a reduced-volume insert so that the donor side volume approximated 6% of the receiver (endothelial or aqueous humor) chamber volume. Fluid was pumped through the anterior chamber to simulate the physiologic tear turnover in vivo. The receiver chamber was bubbled with oxygen:carbon dioxide (95%:5%) to aerate and circulate the fluid. We investigated the in vitro ocular bioavailability of several marketed ophthalmic drug formulations using this model (0.03% flurbiprofen, 0.5% levobunolol, 0.1 and 0.25% fluorometholone, and 1% prednisolone acetate). At 1 min after the dose administration, drug was eluted from the donor chamber at a dose turnover rate of 12%/min. In all experiments, a small percentage of the applied dose penetrated the cornea. Using this chamber device, the ocular bioavailability via corneal absorption ranged between 5 and 16% for solution formulations, whereas the ocular bioavailability for the suspension formulations was less than 0.3%. The major portion of the administered dose was recovered from the donor side effluent. This observation was consistent with findings showing low ocular bioavailability of ophthalmic preparations due to the rapid precorneal washout in vivo. The extent of drug penetrating as its corneal metabolite in the model correlated well to in vitro corneal metabolism rate constants. The new model opens several potentially useful areas of research into ocular absorption.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2324964

  15. Hydroponics gel as a new electrolyte gelling agent for alkaline zinc-air cells

    NASA Astrophysics Data System (ADS)

    Othman, R.; Basirun, W. J.; Yahaya, A. H.; Arof, A. K.

    The viability of hydroponics gel as a new alkaline electrolyte gelling agent is investigated. Zinc-air cells are fabricated employing 12 wt.% KOH electrolyte immobilised with hydroponics gel. The cells are discharged at constant currents of 5, 50 and 100 mA. XRD and SEM analysis of the anode plates after discharge show that the failure mode is due to the formation of zinc oxide insulating layers and not due to any side reactions between the gel and the plate or the electrolyte.

  16. Silicon alleviates Cd stress of wheat seedlings (Triticum turgidum L. cv. Claudio) grown in hydroponics.

    PubMed

    Rizwan, M; Meunier, J-D; Davidian, J-C; Pokrovsky, O S; Bovet, N; Keller, C

    2016-01-01

    We investigated the potential role of silicon in improving tolerance and decreasing cadmium (Cd) toxicity in durum wheat (Triticum turgidum L. durum) either through a reduced Cd uptake or exclusion/sequestration in non-metabolic tissues. For this, plants were grown in hydroponic conditions for 10 days either in presence or absence of 1 mM Si and for 11 additional days in various Cd concentrations (0, 0.5, 5.0 and 50 μM). After harvesting, morphological and physiological parameters as well as elemental concentrations were recorded. Cadmium caused reduction in growth parameters, photosynthetic pigments and mineral nutrient concentrations both in shoots and roots. Shoot and root contents of malate, citrate and aconitate increased, while contents of phosphate, nitrate and sulphate decreased with increasing Cd concentrations in plants. Addition of Si to the nutrient solution mitigated these adverse effects: Cd concentration in shoots decreased while concentration of Cd adsorbed at the root cell apoplasmic level increased together with Zn uptake by roots. Overall, total Cd uptake decreased in presence of Si. There was no co-localisation of Cd and Si either at the shoot or at the root levels. No Cd was detected in leaf phytoliths. In roots, Cd was mainly detected in the cortical parenchyma and Si at the endodermis level, while analysis of the outer thin root surface of the plants grown in the 50 μM Cd + 1 mM Si treatment highlighted non-homogeneous Cd and Si enrichments. These data strongly suggest the existence of a root localised protection mechanism consisting in armoring the root surface by Si- and Cd-bearing compounds and in limiting root-shoot translocation. PMID:26370813

  17. Stimulation of nodulation in field peas (Pisum sativum) by low concentrations of ammonium in hydroponic culture

    NASA Technical Reports Server (NTRS)

    Waterer, J. G.; Vessey, J. K.; Raper, C. D. Jr; Raper CD, J. r. (Principal Investigator)

    1992-01-01

    Although the inhibitory effects of high concentrations of mineral N (> 1.0 mM) on nodule development and function have often been studied, the effects of low, static concentrations of NH4+ (< 1.0 mM) on nodulation are unknown. In the present experiments we examine the effects of static concentrations of NH4+ at 0, 0.1 and 0.5 mM in flowing, hydroponic culture on nodule establishment and nitrogenase activity in field peas [Pisum sativum L. cv. Express (Svalof AB)] for the initial 28 days after planting (DAP). Peas grown in the presence of low concentrations of NH4+ had significantly greater nodule numbers (up to 4-fold) than plants grown without NH4+. Nodule dry weight per plant was significantly higher at 14, 21 and 28 DAP in plants grown in the presence of NH4+, but individual nodule mass was lower than in plants grown without NH4+. The nodulation pattern of the plants supplied with NH4+ was similar to that often reported for supernodulating mutants, however the plants did not express other growth habits associated with supernodulation. Estimates of N2 fixation indicate that the plus-NH4+ peas fixed as much or more N2 than the plants supplied with minus-NH4+ nutrient solution. There were no significant differences in nodule numbers, nodule mass or NH4+ uptake between the plants grown at the two concentrations of NH4+. Nodulation appeared to autoregulate by 14 DAP in the minus-NH4+ treatment. Plant growth and N accumulation in the minus-NH4+ plants lagged behind those of the plus-NH4+ treatments prior to N2 fixation becoming well established in the final week of the experiment. The plus-NH4+ treatments appeared not to elicit autoregulation and plants continued to initiate nodules throughout the experiment.

  18. Effect of bacterial root symbiosis and urea as source of nitrogen on performance of soybean plants grown hydroponically for Bioregenerative Life Support Systems (BLSSs).

    PubMed

    Paradiso, Roberta; Buonomo, Roberta; Dixon, Mike A; Barbieri, Giancarlo; De Pascale, Stefania

    2015-01-01

    Soybean is traditionally grown in soil, where root symbiosis with Bradyrhizobium japonicum can supply nitrogen (N), by means of bacterial fixation of atmospheric N2. Nitrogen fertilizers inhibit N-fixing bacteria. However, urea is profitably used in soybean cultivation in soil, where urease enzymes of telluric microbes catalyze the hydrolysis to ammonium, which has a lighter inhibitory effect compared to nitrate. Previous researches demonstrated that soybean can be grown hydroponically with recirculating complete nitrate-based nutrient solutions. In Space, urea derived from crew urine could be used as N source, with positive effects in resource procurement and waste recycling. However, whether the plants are able to use urea as the sole source of N and its effect on root symbiosis with B. japonicum is still unclear in hydroponics. We compared the effect of two N sources, nitrate and urea, on plant growth and physiology, and seed yield and quality of soybean grown in closed-loop Nutrient Film Technique (NFT) in growth chamber, with or without inoculation with B. japonicum. Urea limited plant growth and seed yield compared to nitrate by determining nutrient deficiency, due to its low utilization efficiency in the early developmental stages, and reduced nutrients uptake (K, Ca, and Mg) throughout the whole growing cycle. Root inoculation with B. japonicum did not improve plant performance, regardless of the N source. Specifically, nodulation increased under fertigation with urea compared to nitrate, but this effect did not result in higher leaf N content and better biomass and seed production. Urea was not suitable as sole N source for soybean in closed-loop NFT. However, the ability to use urea increased from young to adult plants, suggesting the possibility to apply it during reproductive phase or in combination with nitrate in earlier developmental stages. Root symbiosis did not contribute significantly to N nutrition and did not enhance the plant ability to use

  19. Effect of bacterial root symbiosis and urea as source of nitrogen on performance of soybean plants grown hydroponically for Bioregenerative Life Support Systems (BLSSs)

    PubMed Central

    Paradiso, Roberta; Buonomo, Roberta; Dixon, Mike A.; Barbieri, Giancarlo; De Pascale, Stefania

    2015-01-01

    Soybean is traditionally grown in soil, where root symbiosis with Bradyrhizobium japonicum can supply nitrogen (N), by means of bacterial fixation of atmospheric N2. Nitrogen fertilizers inhibit N-fixing bacteria. However, urea is profitably used in soybean cultivation in soil, where urease enzymes of telluric microbes catalyze the hydrolysis to ammonium, which has a lighter inhibitory effect compared to nitrate. Previous researches demonstrated that soybean can be grown hydroponically with recirculating complete nitrate-based nutrient solutions. In Space, urea derived from crew urine could be used as N source, with positive effects in resource procurement and waste recycling. However, whether the plants are able to use urea as the sole source of N and its effect on root symbiosis with B. japonicum is still unclear in hydroponics. We compared the effect of two N sources, nitrate and urea, on plant growth and physiology, and seed yield and quality of soybean grown in closed-loop Nutrient Film Technique (NFT) in growth chamber, with or without inoculation with B. japonicum. Urea limited plant growth and seed yield compared to nitrate by determining nutrient deficiency, due to its low utilization efficiency in the early developmental stages, and reduced nutrients uptake (K, Ca, and Mg) throughout the whole growing cycle. Root inoculation with B. japonicum did not improve plant performance, regardless of the N source. Specifically, nodulation increased under fertigation with urea compared to nitrate, but this effect did not result in higher leaf N content and better biomass and seed production. Urea was not suitable as sole N source for soybean in closed-loop NFT. However, the ability to use urea increased from young to adult plants, suggesting the possibility to apply it during reproductive phase or in combination with nitrate in earlier developmental stages. Root symbiosis did not contribute significantly to N nutrition and did not enhance the plant ability to use

  20. Interactions between active pharmaceutical ingredients and excipients affecting bioavailability: impact on bioequivalence.

    PubMed

    García-Arieta, Alfredo

    2014-12-18

    The aim of the present paper is to illustrate the impact that excipients may have on the bioavailability of drugs and to review existing US-FDA, WHO and EMA regulatory guidelines on this topic. The first examples illustrate that small amounts of sorbitol (7, 50 or 60mg) affect the bioavailability of risperidone, a class I drug, oral solution, in contrast to what is stated in the US-FDA guidance. Another example suggests, in contrast to what is stated in the US-FDA BCS biowaivers guideline, that a small amount of sodium lauryl sulphate (SLS) (3.64mg) affects the bioavailability of risperidone tablets, although the reference product also includes SLS in an amount within the normal range for that type of dosage form. These factors are considered sufficient to ensure that excipients do not affect bioavailability according to the WHO guideline. The alternative criterion, defined in the WHO guideline and used in the FIP BCS biowaivers monographs, that asserts that excipients present in generic products of the ICH countries do not affect bioavailability if used in normal amounts, is shown to be incorrect with an example of alendronate (a class III drug) tablets, where 4mg of SLS increases bioavailability more than 5-fold, although a generic product in the USA contains SLS. Finally, another example illustrates that a 2mg difference in SLS may affect bioavailability of a generic product of a class II drug, even if SLS is contained in the comparator product, and in all cases its amount was within the normal range. Therefore, waivers of in vivo bioequivalence studies (e.g., BCS biowaivers, waivers of certain dosage forms in solution at the time of administration and variations in the excipient composition) should be assessed more cautiously. PMID:25236823

  1. Bioavailability of heavy metals in soils: definitions and practical implementation--a critical review.

    PubMed

    Kim, Rog-Young; Yoon, Jeong-Ki; Kim, Tae-Seung; Yang, Jae E; Owens, Gary; Kim, Kwon-Rae

    2015-12-01

    Worldwide regulatory frameworks for the assessment and remediation of contaminated soils have moved towards a risk-based approach, taking contaminant bioavailability into consideration. However, there is much debate on the precise definition of bioavailability and on the standardization of methods for the measurement of bioavailability so that it can be reliably applied as a tool for risk assessment. Therefore, in this paper, we reviewed the existing definitions of heavy metal bioavailability in relation to plant uptake (phytoavailability), in order to better understand both the conceptual and operational aspects of bioavailability. The related concepts of specific and non-specific adsorption, as well as complex formation and organic ligand affinity were also intensively discussed to explain the variations of heavy metal solubility and mobility in soils. Further, the most frequently used methods to measure bioavailable metal soil fractions based on both chemical extractions and mechanistic geochemical models were reviewed. For relatively highly mobile metals (Cd, Ni, and Zn), a neutral salt solution such as 0.01 M CaCl2 or 1 M NH4NO3 was recommended, whereas a strong acid or chelating solution such as 0.43 M HNO3 or 0.05 M DTPA was recommended for strongly soil-adsorbed and less mobile metals (Cu, Cr, and Pb). While methods which assessed the free metal ion activity in the pore water such as DGT and DMT or WHAM/Model VI, NICA-Donnan model, and TBLM are advantageous for providing a more direct measure of bioavailability, few of these models have to date been properly validated. PMID:25841357

  2. BIOAVAILABILITY OF HALOACETATES IN HUMAN SUBJECTS

    EPA Science Inventory

    The objective of this project is to characterize the absorption, disposition and oral bioavailability of chlorinated and brominated haloacetates in human volunteers after consumption of drinking water containing a natural mixture of these compounds. We hypothesize that accurat...

  3. An experimental set-up to study carbon, water, and nitrate uptake rates by hydroponically grown plants.

    PubMed

    Andriolo, J L; Le Bot, J; Gary, C; Sappe, G; Orlando, P; Brunel, B; Sarrouy, C

    1996-01-01

    The experimental system described allows concomitant hourly measurements of CO2, H2O, and NO3 uptake rates by plants grown hydroponically in a greenhouse. Plants are enclosed in an airtight chamber through which air flows at a controlled speed. Carbon dioxide exchange and transpiration rates are determined from respective differences of concentrations of CO2 and water vapor of the air at the system inlet and outlet. This set-up is based on the "open-system" principle with improvements made on existing systems. For instance, propeller anemometers are used to monitor air flow rates in the chamber. From their signal it is possible to continuously adjust air speed to changing environmental conditions and plant activity. The air temperature inside the system therefore never rises above that outside. Water and NO3 uptake rates are calculated at time intervals from changes in the volume and the NO3 concentration of the nutrient solution in contact with the roots. The precise measurement of the volume of solution is achieved using a balance which has a higher precision than any liquid level sensors. Nitrate concentration is determined in the laboratory from aliquots of solution sampled at time intervals. A number of test runs are reported which validate the measurements and confirm undisturbed conditions within the system. Results of typical diurnal changes in CO2, H2O, and NO3 uptake rates by fruiting tomato plants are also presented. PMID:11541097

  4. Bioavailability of intramuscularly administered tenoxicam.

    PubMed

    Stebler, T; Guentert, T W

    1993-08-01

    Bioavailability of intramuscularly administered tenoxicam relative to single oral and relative to intravenous doses was determined in two separate randomized crossover studies. Twelve healthy volunteers (12 males, age 20-30 years) received a rapid intravenous injection and a single intramuscular dose and 12 other subjects (11 males, 1 female, age 21-25 years) a single oral and a single intramuscular dose of 20 mg of tenoxicam on two different occasions. The wash-out period between the two consecutive treatments was 4 weeks. Plasma concentrations after dosing were determined by a specific HPLC method. Differences in tenoxicam concentration-time profiles after the different routes of administration were limited to the first 2 h after dosing. Later, plasma concentrations were almost superimposable within and across the two studies. The extent of absorption of intramuscularly administered tenoxicam was complete (mean +/- CV per cent: F(abs) 0.99 +/- 20 per cent) with no difference between the two extravascular administrations (F(rel) 0.95 +/- 10 per cent, intramuscular vs oral). After intramuscular administration tenoxicam was more rapidly absorbed compared to the oral dose (Tmax 0.71 h +/- 80 per cent vs 1.4 h +/- 62 per cent; p > 0.05). Peak concentrations after oral and intramuscular administration (Cmax 2.5 mg l-1 +/- 19 per cent vs 2.7 mg l-1 +/- 14 per cent; p < 0.05) were very similar. PMID:8218966

  5. Biomass accumulation in hydroponically grown sweetpotato in a controlled environment: a preliminary study.

    PubMed

    Hill, J; Douglas, D; David, P; Mortley, D; Trotman, A; Bonsi, C

    1996-12-01

    In the development of a plant growth model, the assumptions made and the general equations representing an understanding of plant growth are gradually refined as more information is acquired through experimentation. One such experiment that contributed to sweetpotato model development consisted of measuring biomass accumulation of sweetpotato grown in hydroponic culture in a plant growth chamber. Plants were started from fifteen centimeter long 'TU-82-155' sweetpotato vine cuttings spaced 25 cm apart in each of 18 rectangular growing channels (0.15 by 0.15 by 1.2m) in a system designed to use the nutrient film technique (NFT). Each channel contained four plants. The 3.5m by 5.2m plant growth chamber environmental parameters included an 18h photoperiod, 500 micromoles m-2 s-1 of photosynthetic photon flux (PPF), and a diurnal light/dark temperature of 28 degrees C/22 degrees C. The relative humidity was 80 +/- 5% and the CO2 partial pressure was ambient (350 ppm). The nutrient solution contained in 30L reservoirs was a modified half Hoagland's solution with a 1:2.4 N:K ratio and a pH of 6.2. Solution replenishment occurred when the electrical conductivity (EC) level dropped below 1050. Plants were harvested at 15 days after planting (DAP) and weekly thereafter until day 134. By 57 DAP, stems and fibrous roots had acquired 90% of their total dry biomass, while leaves had reached 84% of their maximum dry biomass. Beginning at 64 DAP dry biomass accumulation in the storage roots dominated the increase in dry biomass for the plants. Dry weight of storage roots at 120 DAP was 165 g/plant or 1.1 kg/m2. Resulting growth curves were consistent with the physiological processes occurring in the plant. Results from this study will be incorporated in a plant growth model for use in conjunction with controlled life support systems for long-term manned space missions. PMID:11541575

  6. Biomass accumulation in hydroponically grown sweetpotato in a controlled environment: a preliminary study

    NASA Technical Reports Server (NTRS)

    Hill, J.; Douglas, D.; David, P.; Mortley, D.; Trotman, A.; Bonsi, C.

    1996-01-01

    In the development of a plant growth model, the assumptions made and the general equations representing an understanding of plant growth are gradually refined as more information is acquired through experimentation. One such experiment that contributed to sweetpotato model development consisted of measuring biomass accumulation of sweetpotato grown in hydroponic culture in a plant growth chamber. Plants were started from fifteen centimeter long 'TU-82-155' sweetpotato vine cuttings spaced 25 cm apart in each of 18 rectangular growing channels (0.15 by 0.15 by 1.2m) in a system designed to use the nutrient film technique (NFT). Each channel contained four plants. The 3.5m by 5.2m plant growth chamber environmental parameters included an 18h photoperiod, 500 micromoles m-2 s-1 of photosynthetic photon flux (PPF), and a diurnal light/dark temperature of 28 degrees C/22 degrees C. The relative humidity was 80 +/- 5% and the CO2 partial pressure was ambient (350 ppm). The nutrient solution contained in 30L reservoirs was a modified half Hoagland's solution with a 1:2.4 N:K ratio and a pH of 6.2. Solution replenishment occurred when the electrical conductivity (EC) level dropped below 1050. Plants were harvested at 15 days after planting (DAP) and weekly thereafter until day 134. By 57 DAP, stems and fibrous roots had acquired 90% of their total dry biomass, while leaves had reached 84% of their maximum dry biomass. Beginning at 64 DAP dry biomass accumulation in the storage roots dominated the increase in dry biomass for the plants. Dry weight of storage roots at 120 DAP was 165 g/plant or 1.1 kg/m2. Resulting growth curves were consistent with the physiological processes occurring in the plant. Results from this study will be incorporated in a plant growth model for use in conjunction with controlled life support systems for long-term manned space missions.

  7. Proliferation of Escherichia coli O157:H7 in soil and hydroponic microgreen production systems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Radish (Raphanus sativus var. longipinnatus) microgreens were produced from seeds inoculated with Escherichia coli O157: H7 using soil substitute and hydroponic production systems. E. coli populations on the edible and inedible parts of harvested microgreen plants and in growth medium were examined....

  8. Animal and Environmental Impact on the Presence and Distribution of Salmonella spp. in Hydroponic Tomato Greenhouses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    From 2003 to 2004, we studied the impact of environmental influences on the microbiological quality of a hydroponic tomato farm. The presence of Salmonella was investigated on 906 samples of tomatoes and 714 environmental samples. The farm comprised 14 greenhouses and a technologically advanced pack...

  9. Effects of Phosphorus on Morphology of Hydroponically Grown Scaevola aemula R. Br. "Whirlwind Blue"

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The popular hanging basket plant, fan-flower (Scaevola aemula R. Br. ‘Whirlwind Blue’), is cultivated from low phosphorus soils and requires minimal supplemental phosphorus. To accurately evaluate the effects of phosphorus on morphology, fan-flower was grown hydroponically in order to maintain conc...

  10. EFFECTS OF HUMIC SUBSTANCES ON ATTENUATION OF METALS: BIOAVAILABILITY AND MOBILITY IN SOIL

    EPA Science Inventory

    Humic substances play vastly important roles in metal behavior in a wide variety of environments. They can affect the mobility and bioavailability of metals by binding and sequestration thereby decreasing the mobility of a metal. They can also transport metals into solution or ...

  11. Atorvastatin solid dispersion for bioavailability enhancement.

    PubMed

    Shamsuddin; Fazil, Mohammad; Ansari, Shahid H; Ali, Javed

    2016-01-01

    Atorvastatin calcium is a lipid-lowering agent. It has approximately 15% of bioavailability, remaining amount of drug showed adverse effect which is undesirable for patients. The objective of the study was to enhance the solubility and a dissolution profile of the atorvastatin (AT) calcium. Solid dispersion (SD) is a technique which enhances the solubility and a dissolution profile of poorly soluble drug. Various methods are being used for SDs such as microwave irradiation fusion, kneading, solvent evaporation, fusion, and dropping method. The authors have used here conventional fusion method using PEG 4000 as a hydrophilic carrier. The solubility of pure drug, physical mixture using PEG 4000 (1:3), and SD in phosphate buffer solutions (pH 6.8) was found to be 55.33 ± 0.66, 81.89 ± 2.35, and 93.66 ± 1.35, respectively. Fourier transform infrared and differential scanning calorimetry study showed the significant peak shift of drug in SD. It indicated that the nature of drug had been changed from crystalline form to amorphous form due to conversion into SD formulation. The dissolution rate was significantly increased when the drug polyethylene glycol 4000 ratio was 1:3. The mean cumulative percentage drugs release from pure drug, physical mixture, marketed tablet, and SD at 1 h was 28.92 ± 1.66%, 55.26 ± 0.95%, 72.16 ± 1.33%, and 91.66 ± 1.65%, respectively. It was concluded that the solubility and dissolution profile of SD of AT calcium showed the enhancement of solubility and dissolution when compared with marketed preparations. PMID:26955607

  12. Atorvastatin solid dispersion for bioavailability enhancement

    PubMed Central

    Shamsuddin; Fazil, Mohammad; Ansari, Shahid H.; Ali, Javed

    2016-01-01

    Atorvastatin calcium is a lipid-lowering agent. It has approximately 15% of bioavailability, remaining amount of drug showed adverse effect which is undesirable for patients. The objective of the study was to enhance the solubility and a dissolution profile of the atorvastatin (AT) calcium. Solid dispersion (SD) is a technique which enhances the solubility and a dissolution profile of poorly soluble drug. Various methods are being used for SDs such as microwave irradiation fusion, kneading, solvent evaporation, fusion, and dropping method. The authors have used here conventional fusion method using PEG 4000 as a hydrophilic carrier. The solubility of pure drug, physical mixture using PEG 4000 (1:3), and SD in phosphate buffer solutions (pH 6.8) was found to be 55.33 ± 0.66, 81.89 ± 2.35, and 93.66 ± 1.35, respectively. Fourier transform infrared and differential scanning calorimetry study showed the significant peak shift of drug in SD. It indicated that the nature of drug had been changed from crystalline form to amorphous form due to conversion into SD formulation. The dissolution rate was significantly increased when the drug polyethylene glycol 4000 ratio was 1:3. The mean cumulative percentage drugs release from pure drug, physical mixture, marketed tablet, and SD at 1 h was 28.92 ± 1.66%, 55.26 ± 0.95%, 72.16 ± 1.33%, and 91.66 ± 1.65%, respectively. It was concluded that the solubility and dissolution profile of SD of AT calcium showed the enhancement of solubility and dissolution when compared with marketed preparations. PMID:26955607

  13. Comparison of partial extraction reagents for assessing potential bioavailability of heavy metals in sediments.

    PubMed

    Brady, James P; Kinaev, Irina; Goonetilleke, Ashantha; Ayoko, Godwin A

    2016-05-15

    Assessment of heavy metal bioavailability in sediments is complex because of the number of partial extraction methods available for the assessment and the general lack of certified reference materials. This study evaluates five different extraction methodologies to ascertain the relative strengths and weaknesses of each method. The results are then compared to previously published work to ascertain the most effective partial extraction technique, which was established to dilute (0.75-1M) nitric acid solutions. These results imply that single reagent; weak acid extractions provide a better assessment of potentially bioavailable metals than the chelating agents used in sequential extraction methods. PMID:27036084

  14. Study of the microbial dynamics in the root environment of closed, hydroponic cultivation systems for tomato using phospholipid fatty acid profiles.

    PubMed

    Waechter-Kristensen, B; Khalil, S; Sundin, P; Englund, J E; Gertsson, U E; Jensen, P

    1996-12-01

    A more basic understanding of the microbial dynamics of closed, hydroponic cultivation systems is needed. We therefore initiated a study of the microbial community inhabiting the root environment, using phospholipid fatty acid (PLFA) profiles, and started to examine whether changes in the microbial population structure would result from the introduction of selected isolates of plant growth-promoting rhizobacteria (PGPR). Tomato were cultured in deep-flow systems with circulating nutrient solution. Bacteria were sampled from tomato roots at three locations, longitudinally, in the gutters of a control system and in two systems inoculated with PGPR. In the beginning of the gutters the PLFA profiles were similar in all systems, whereas the profiles differed in the gutter ends (following the direction of flow). In the control system, and in a treatment inoculated with two Gram-negative and one Gram-positive PGPR strain, the relative proportion of PLFAs characteristic to Gram-positive bacteria was highest at the end of the gutter. In a treatment inoculated only with a Gram-negative PGPR strain, the relative proportion of PLFAs characteristic of Gram-negative bacteria was highest at the end of the gutter. The results indicate a complex situation with different micro-environments distributed along the root mat. It can also be concluded that PLFA profiles may be useful tools in the study of the microbiology of closed hydroponic plant cultivation systems. PMID:11541571

  15. Bioavailability of zinc from sweet potato roots and leaves

    SciTech Connect

    Baiden, H.N.; Ercanli-Huffman, F.G.

    1986-03-05

    Bioavailability of zinc from sweet potato (SP) roots and leaves were determined, by extrinsic labeling technique, in rats fed control and zinc deficient diets. Weanling male Sprague Dawley (SD) rats (60-75g) were divided into 4 groups, and fed laboratory chow, a control diet (ad libitum and pair fed) and a zinc deficient diet, for 4 weeks. Each group then was divided into at least 2 sub groups, containing 6 rats, which were intubated with one of 3 tubing solutions extrinsically labeled with /sup 65/Zn; baked sweet potato roots (BSPR), raw sweet potato leaves (RSPL) and cooked sweet potato leaves (CSPL). Five hours after intubation the rats were sacrificed, blood, liver, testes, spleen, heart, brain, thymus and lungs were removed. Feces, urine, and GI tract contents were collected and their /sup 65/Zn activity was determined in a gamma counter. In all treatment groups zinc bioavailability from BSPR, RSPL or CSPL were not significantly different. Zinc deficient rats absorbed significantly more (P < 0.01) /sup 65/Zn (86-90% of the dose), regardless of type of tubing solution than the pairfed or control animals (35-58% of the dose). The highest retention of /sup 65/Zn was found in the liver (12-20% of absorbed dose), GI tract (6-17% of absorbed dose), kidney (2-8% of absorbed dose), and blood (1-5% of absorbed dose). The lowest retention was found in the brain, heart, thymus and testes. (< 1% of absorbed dose).

  16. Vanadium bioavailability in soils amended with blast furnace slag.

    PubMed

    Larsson, Maja A; Baken, Stijn; Smolders, Erik; Cubadda, Francesco; Gustafsson, Jon Petter

    2015-10-15

    Blast furnace (BF) slags are commonly applied as soil amendments and in road fill material. In Sweden they are also naturally high in vanadium. The aim of this study was to assess the vanadium bioavailability in BF slags when applied to soil. Two soils were amended with up to 29% BF slag (containing 800 mg V kg(-1)) and equilibrated outdoors for 10 months before conducting a barley shoot growth assay. Additional soil samples were spiked with dissolved vanadate(V) for which assays were conducted two weeks (freshly spiked) and 10 months (aged) after spiking. The BF slag vanadium was dominated by vanadium(III) as shown by V K-edge XANES spectroscopy. In contrast, results obtained by HPLC-ICP-MS showed that vanadium(V), the most toxic vanadium species, was predominant in the soil solution. Barley shoot growth was not affected by the BF slag additions. This was likely due to limited dissolution of vanadium from the BF slag, preventing an increase of dissolved vanadium above toxic thresholds. The difference in vanadium bioavailability among treatments was explained by the vanadium concentration in the soil solution. It was concluded that the vanadium in BF slag is sparingly available. These findings should be of importance in environmental risk assessment. PMID:25917693

  17. Polyphenols: Extraction Methods, Antioxidative Action, Bioavailability and Anticarcinogenic Effects.

    PubMed

    Brglez Mojzer, Eva; Knez Hrnčič, Maša; Škerget, Mojca; Knez, Željko; Bren, Urban

    2016-01-01

    Being secondary plant metabolites, polyphenols represent a large and diverse group of substances abundantly present in a majority of fruits, herbs and vegetables. The current contribution is focused on their bioavailability, antioxidative and anticarcinogenic properties. An overview of extraction methods is also given, with supercritical fluid extraction highlighted as a promising eco-friendly alternative providing exceptional separation and protection from degradation of unstable polyphenols. The protective role of polyphenols against reactive oxygen and nitrogen species, UV light, plant pathogens, parasites and predators results in several beneficial biological activities giving rise to prophylaxis or possibly even to a cure for several prevailing human diseases, especially various cancer types. Omnipresence, specificity of the response and the absence of or low toxicity are crucial advantages of polyphenols as anticancer agents. The main problem represents their low bioavailability and rapid metabolism. One of the promising solutions lies in nanoformulation of polyphenols that prevents their degradation and thus enables significantly higher concentrations to reach the target cells. Another, more practiced, solution is the use of mixtures of various polyphenols that bring synergistic effects, resulting in lowering of the required therapeutic dose and in multitargeted action. The combination of polyphenols with existing drugs and therapies also shows promising results and significantly reduces their toxicity. PMID:27409600

  18. Quantifying Carbon Bioavailability in Northeast Siberian Soils

    NASA Astrophysics Data System (ADS)

    Heslop, J.; Chandra, S.; Sobczak, W. V.; Spektor, V.; Davydova, A.; Holmes, R. M.; Bulygina, E. B.; Schade, J. D.; Frey, K. E.; Bunn, A. G.; Walter Anthony, K.; Zimov, S. A.; Zimov, N.

    2010-12-01

    Soils in Northeast Siberia, particularly carbon-rich yedoma (Pleistocene permafrost) soils, have the potential to release large amounts of carbon dioxide and methane due to permafrost thaw and thermokarst activity. In order to quantify the amount of carbon release potential in these soils, it is important to understand carbon bioavailability for microbial consumption in the permafrost. In this study we measured amounts of bioavailable soil carbon across five locations in the Kolyma River Basin, NE Siberia. At each location, we sampled four horizons (top active layer, bottom active layer, Holocene optimum permafrost, and Pleistocene permafrost) and conducted soil extracts for each sample. Filtered and unfiltered extracts were used in biological oxygen demand experiments to determine the dissolved and particulate bioavailable carbon potential for consumption in the soil. Concentrations of bioavailable carbon were 102-608 mg C/kg dry soil for filtered extracts and 115-703 mg C/kg dry soil for unfiltered extracts. Concentrations of carbon respired per gram of dry soil were roughly equal for both the DOC and POC extracts (P<0.001), suggesting that bioavailable soil carbon is predominately in the dissolved form or the presence of an additional unknown limitation preventing organisms from utilizing carbon in the particulate form. Concentrations of bioavailable carbon were similar across the different sampling locations but differed among horizons. The top active layer (102-703 mg C/kg dry soil), Holocene optimum permafrost (193-481 mg C/kg dry soil), and Pleistocene permafrost (151-589 mg C/kg dry soil) horizons had the highest amounts of bioavailable carbon, and the bottom active layer (115-179 mg C/kg dry soil) horizon had the lowest amounts. For comparison, ice wedges had bioavailable carbon concentrations of 23.0 mg C/L and yedoma runoff from Duvyanni Yar had concentrations of 306 mg C/L. Pleistocene permafrost soils had similar concentrations of bioavailable carbon

  19. Bioavailability enhancers of herbal origin: an overview.

    PubMed

    Kesarwani, Kritika; Gupta, Rajiv; Mukerjee, Alok

    2013-04-01

    Recently, the use of herbal medicines has been increased all over the world due to their therapeutic effects and fewer adverse effects as compared to the modern medicines. However, many herbal drugs and herbal extracts despite of their impressive in-vitro findings demonstrates less or negligible in-vivo activity due to their poor lipid solubility or improper molecular size, resulting in poor absorption and hence poor bioavailability. Nowadays with the advancement in the technology, novel drug delivery systems open the door towards the development of enhancing bioavailability of herbal drug delivery systems. For last one decade many novel carriers such as liposomes, microspheres, nanoparticles, transferosomes, ethosomes, lipid based systems etc. have been reported for successful modified delivery of various herbal drugs. Many herbal compounds including quercetin, genistein, naringin, sinomenine, piperine, glycyrrhizin and nitrile glycoside have demonstrated capability to enhance the bioavailability. The objective of this review is to summarize various available novel drug delivery technologies which have been developed for delivery of drugs (herbal), and to achieve better therapeutic response. An attempt has also been made to compile a profile on bioavailability enhancers of herbal origin with the mechanism of action (wherever reported) and studies on improvement in drug bioavailability, exhibited particularly by natural compounds. PMID:23620848

  20. Bioavailability enhancers of herbal origin: An overview

    PubMed Central

    Kesarwani, Kritika; Gupta, Rajiv

    2013-01-01

    Recently, the use of herbal medicines has been increased all over the world due to their therapeutic effects and fewer adverse effects as compared to the modern medicines. However, many herbal drugs and herbal extracts despite of their impressive in-vitro findings demonstrates less or negligible in-vivo activity due to their poor lipid solubility or improper molecular size, resulting in poor absorption and hence poor bioavailability. Nowadays with the advancement in the technology, novel drug delivery systems open the door towards the development of enhancing bioavailability of herbal drug delivery systems. For last one decade many novel carriers such as liposomes, microspheres, nanoparticles, transferosomes, ethosomes, lipid based systems etc. have been reported for successful modified delivery of various herbal drugs. Many herbal compounds including quercetin, genistein, naringin, sinomenine, piperine, glycyrrhizin and nitrile glycoside have demonstrated capability to enhance the bioavailability. The objective of this review is to summarize various available novel drug delivery technologies which have been developed for delivery of drugs (herbal), and to achieve better therapeutic response. An attempt has also been made to compile a profile on bioavailability enhancers of herbal origin with the mechanism of action (wherever reported) and studies on improvement in drug bioavailability, exhibited particularly by natural compounds. PMID:23620848

  1. Role of entrained droplet oil on the bioavailability of petroleum substances in aqueous exposures.

    PubMed

    Redman, A D

    2015-08-15

    Bioavailability of petroleum substances is a complex issue that is affected by substance composition, the physicochemical properties of the individual constituents, and the exposure preparation system. The present study applies mechanistic fate and effects models to characterize the role of droplet oil on dissolved exposure and predicted effects from both neat and weathered crude oils, and refined fuel oils. The main effect from droplet oil is input of additional dissolved hydrocarbons to the exposure system following preparation of the initial stock solution. Toxicity was characterized using toxic units (TU) and shows that replenishment of bioavailable hydrocarbons by droplets in toxicity tests with low droplet content (e.g., <1mg/L) is negligible, consistent with typical exposure conditions following open ocean oil spills. Further, the use of volumetric exposure metrics (e.g., mg/L) introduces considerable variability and the bioavailability-based metrics (e.g., TUs) provide a more consistent basis for understanding oil toxicity data. PMID:26072047

  2. Influence of Dissolved Organic Matter on Tetracycline Bioavailability to an Antibiotic-Resistant Bacterium.

    PubMed

    Chen, Zeyou; Zhang, Yingjie; Gao, Yanzheng; Boyd, Stephen A; Zhu, Dongqiang; Li, Hui

    2015-09-15

    Complexation of tetracycline with dissolved organic matter (DOM) in aqueous solution could alter the bioavailability of tetracycline to bacteria, thereby alleviating selective pressure for development of antibiotic resistance. In this study, an Escherichia coli whole-cell bioreporter construct with antibiotic resistance genes coupled to green fluorescence protein was exposed to tetracycline in the presence of DOM derived from humic acids. Complexation between tetracycline and DOM diminished tetracycline bioavailability to E. coli, as indicated by reduced expression of antibiotic resistance genes. Increasing DOM concentration resulted in decreasing bioavailability of tetracycline to the bioreporter. Freely dissolved tetracycline (not complexed with DOM) was identified as the major fraction responsible for the rate and magnitude of antibiotic resistance genes expressed. Furthermore, adsorption of DOM on bacterial cell surfaces inhibited tetracycline diffusion into the bioreporter cells. The magnitude of the inhibition was related to the amount of DOM adsorbed and tetracycline affinity for the DOM. These findings provide novel insights into the mechanisms by which the bioavailability of tetracycline antibiotics to bacteria is reduced by DOM present in water. Agricultural lands receiving livestock manures commonly have elevated levels of both DOM and antibiotics; the DOM could suppress the bioavailability of antibiotics, hence reducing selective pressure on bacteria for development of antibiotic resistance. PMID:26370618

  3. Concentrations and bioavailability of cadmium and lead in cocoa powder and related products.

    PubMed

    Mounicou, S; Szpunar, J; Andrey, D; Blake, C; Lobinski, R

    2003-04-01

    Concentrations and bioavailability of cadmium (Cd) and lead (Pb) were determined in cocoa powders and related products (beans, liquor, butter) of different geographical origins. Particular attention was paid to the fractionation of these metals, which was investigated by determining the metal fraction soluble in extractant solutions acting selectively with regard to the different classes of ligands. The targeted classes of Cd and Pb species included: water-soluble compounds, polypeptide and polysaccharide complexes, and compounds soluble in simulated gastrointestinal conditions. The bioavailability of Cd and Pb from cocoa powder, liquor and butter was evaluated using a sequential enzymolysis approach. The data obtained as a function of the geographical origin of the samples indicated strong differences not only in terms of the total Cd and Pb concentrations, but also with regard to the bioavailability of these metals. The Cd concentrations in the cocoa powders varied from 94 to 1833 microg kg(-1), of which 10-50% was potentially bioavailable. The bioavailability of Pb was generally below 10% and the concentrations measured in the cocoa powders were in the 11-769 microg kg(-1) range. Virtually all the Cd and most of Pb were found in the cocoa powder after the pressing of the liquor. PMID:12775476

  4. Formulation and Characterization of Drug Loaded Nonionic Surfactant Vesicles (Niosomes) for Oral Bioavailability Enhancement

    PubMed Central

    Kamboj, Sunil; Saini, Vipin; Bala, Suman

    2014-01-01

    Nonionic surfactant vesicles (niosomes) were formulated with an aim of enhancing the oral bioavailability of tenofovir disoproxil fumarate (TDF), an anti-HIV drug. Niosomes were formulated by conventional thin film hydration technique with different molar ratios of surfactant, cholesterol, and dicetyl phosphate. The formulated niosomes were found spherical in shape, ranging from 2.95 μm to 10.91 μm in size. Vesicles with 1 : 1 : 0.1 ratios of surfactant : cholesterol : dicetyl phosphate with each grade of span were found to have higher entrapment efficiencies, which were further selected for in vitro and in vivo studies. Vesicles formulated with sorbitan monostearate were found to have maximum drug release (99.091%) at the end of 24 hours and followed zero order release kinetics. The results of in vivo study revealed that the niosomes significantly enhanced the oral bioavailability of TDF in rats after a dose of 95 mg/kg. The average relative bioavailability of niosomes in relation to plane drug solution was found to be 2.58, indicating more than twofold increase in oral bioavailability of TDF. Significant increase in mean residential time (MRT) was also found, reflecting release retarding efficacy of the vesicles. In conclusion, niosomes could be a promising delivery for TDF with improved oral bioavailability and prolonged release profiles. PMID:24672401

  5. DELAY OF EXPRESSION OF POWDERY MILDEW ON ZINNIA GROWN HYDROPONICALLY IN HOAGLAND'S SOLUTION FORTIFIED WITH SILICON

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Powdery mildew, caused by the fungus Erysiphe cichoracearum, is one of the most common foliar diseases that occur in greenhouse bedding plant production. Although powdery mildews are somewhat host specific, E. cichoracearum is reported to have a wide host range which includes the commonly grown be...

  6. Nutrient uptake of ornamental plants exposed to arsenic in hydroponic solution

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Arsenic-based agro-chemicals have contaminated considerable acreage on turf-farms, orchards, and around horticultural production structures. A study was undertaken to evaluate iris (Iris virginica), switchgrass (Panicum virgatum), Tithonia rotundiflora, Coreopsis lanceolata, Sunflower (Helianthus an...

  7. Bioavailability of Polyphenol Liposomes: A Challenge Ahead

    PubMed Central

    Mignet, Nathalie; Seguin, Johanne; Chabot, Guy G.

    2013-01-01

    Dietary polyphenols, including flavonoids, have long been recognized as a source of important molecules involved in the prevention of several diseases, including cancer. However, because of their poor bioavailability, polyphenols remain difficult to be employed clinically. Over the past few years, a renewed interest has been devoted to the use of liposomes as carriers aimed at increasing the bioavailability and, hence, the therapeutic benefits of polyphenols. In this paper, we review the causes of the poor bioavailability of polyphenols and concentrate on their liposomal formulations, which offer a means of improving their pharmacokinetics and pharmacodynamics. The problems linked to their development and their potential therapeutic advantages are reviewed. Future directions for liposomal polyphenol development are suggested. PMID:24300518

  8. Bioavailability of gold nanomaterials to plants: importance of particle size and surface coating.

    PubMed

    Judy, Jonathan D; Unrine, Jason M; Rao, William; Wirick, Sue; Bertsch, Paul M

    2012-08-01

    We used the model organisms Nicotiana tabacum L. cv Xanthi (tobacco) and Triticum aestivum (wheat) to investigate plant uptake of 10-, 30-, and 50-nm diameter Au manufactured nanomaterials (MNMs) coated with either tannate (T-MNMs) or citrate (C-MNMs). Primary particle size, hydrodynamic size, and zeta potential were characterized using transmission electron microscopy (TEM), dynamic light scattering (DLS), and electrophoretic mobility measurements, respectively. Plants were exposed to NPs hydroponically for 3 or 7 days for wheat and tobacco, respectively. Volume averaged Au concentrations were determined using inductively coupled plasma mass spectrometry (ICP-MS). Spatial distribution of Au in tissue samples was determined using laser ablation ICP-MS (LA-ICP-MS) and scanning X-ray fluorescence microscopy (μXRF). Both C-MNMs and T-MNMs of each size treatment bioaccumulated in tobacco, but no bioaccumulation of MNMs was observed for any treatment in wheat. These results indicate that MNMs of a wide range of size and with different surface chemistries are bioavailable to plants, provide mechanistic information regarding the role of cell wall pores in plant uptake of MNMs, and raise questions about the importance of plant species to MNM bioaccumulation. PMID:22784043

  9. Chemistry, stability and bioavailability of resveratrol.

    PubMed

    Francioso, Antonio; Mastromarino, Paola; Masci, Alessandra; d'Erme, Maria; Mosca, Luciana

    2014-05-01

    Resveratrol is a bioactive polyphenol found in many vegetables. It is well known for its multiple pharmacological activities, such as anti-inflammatory, antioxidant, antimicrobial, anticancer, neuroprotective and cardioprotective effects. In vitro evidence of resveratrol efficacy is widespread, however, many concerns regarding its effectiveness in vivo arise from its poor stability in vitro and bioavailability following oral ingestion. This review focuses on the in vitro stability, with special focus on the photochemical stability of resveratrol, and on the therapeutic perspectives of this molecule due to its low bioavailability. PMID:24329932

  10. Bioavailability of Plant-Derived Antioxidants

    PubMed Central

    Abourashed, Ehab A.

    2013-01-01

    Natural products with antioxidant properties have been extensively utilized in the pharmaceutical and food industry and have also been very popular as health-promoting herbal products. This review provides a summary of the literature published around the first decade of the 21st century regarding the oral bioavailability of carotenoids, polyphenols and sulfur compounds as the three major classes of plant-derived antioxidants. The reviewed original research includes more than 40 compounds belonging to the above mentioned classes of natural antioxidants. In addition, related reviews published during the same period have been cited. A brief introduction to general bioavailability-related definitions, procedures and considerations is also included. PMID:26784467

  11. Advances in Computationally Modeling Human Oral Bioavailability

    PubMed Central

    Wang, Junmei; Hou, Tingjun

    2015-01-01

    Although significant progress has been made in experimental high throughput screening (HTS) of ADME (absorption, distribution, metabolism, excretion) and pharmacokinetic properties, the ADME and Toxicity (ADME-Tox) in silico modeling is still indispensable in drug discovery as it can guide us to wisely select drug candidates prior to expensive ADME screenings and clinical trials. Compared to other ADME-Tox properties, human oral bioavailability (HOBA) is particularly important but extremely difficult to predict. In this paper, the advances in human oral bioavailability modeling will be reviewed. Moreover, our deep insight on how to construct more accurate and reliable HOBA QSAR and classification models will also discussed. PMID:25582307

  12. Advances in computationally modeling human oral bioavailability.

    PubMed

    Wang, Junmei; Hou, Tingjun

    2015-06-23

    Although significant progress has been made in experimental high throughput screening (HTS) of ADME (absorption, distribution, metabolism, excretion) and pharmacokinetic properties, the ADME and Toxicity (ADME-Tox) in silico modeling is still indispensable in drug discovery as it can guide us to wisely select drug candidates prior to expensive ADME screenings and clinical trials. Compared to other ADME-Tox properties, human oral bioavailability (HOBA) is particularly important but extremely difficult to predict. In this paper, the advances in human oral bioavailability modeling will be reviewed. Moreover, our deep insight on how to construct more accurate and reliable HOBA QSAR and classification models will also discussed. PMID:25582307

  13. Bioavailability of Metal Ions and Evolutionary Adaptation

    PubMed Central

    Hong Enriquez, Rolando P.; Do, Trang N.

    2012-01-01

    The evolution of life on earth has been a long process that began nearly 3.5 × 109 years ago. In their initial moments, evolution was mainly influenced by anaerobic environments; with the rise of O2 and the corresponding change in bioavailability of metal ions, new mechanisms of survival were created. Here we review the relationships between ancient atmospheric conditions, metal ion bioavailability and adaptation of metals homeostasis during early evolution. A general picture linking geochemistry, biochemistry and homeostasis is supported by the reviewed literature and is further illustrated in this report using simple database searches. PMID:25371266

  14. An improved, low-cost, hydroponic system for growing Arabidopsis and other plant species under aseptic conditions

    PubMed Central

    2014-01-01

    Background Hydroponics is a plant growth system that provides a more precise control of growth media composition. Several hydroponic systems have been reported for Arabidopsis and other model plants. The ease of system set up, cost of the growth system and flexibility to characterize and harvest plant material are features continually improved in new hydroponic system reported. Results We developed a hydroponic culture system for Arabidopsis and other model plants. This low cost, proficient, and novel system is based on recyclable and sterilizable plastic containers, which are readily available from local suppliers. Our system allows a large-scale manipulation of seedlings. It adapts to different growing treatments and has an extended growth window until adult plants are established. The novel seed-holder also facilitates the transfer and harvest of seedlings. Here we report the use of our hydroponic system to analyze transcriptomic responses of Arabidopsis to nutriment availability and plant/pathogen interactions. Conclusions The efficiency and functionality of our proposed hydroponic system is demonstrated in nutrient deficiency and pathogenesis experiments. Hydroponically grown Arabidopsis seedlings under long-time inorganic phosphate (Pi) deficiency showed typical changes in root architecture and high expression of marker genes involved in signaling and Pi recycling. Genome-wide transcriptional analysis of gene expression of Arabidopsis roots depleted of Pi by short time periods indicates that genes related to general stress are up-regulated before those specific to Pi signaling and metabolism. Our hydroponic system also proved useful for conducting pathogenesis essays, revealing early transcriptional activation of pathogenesis-related genes. PMID:24649917

  15. Animal versus human oral drug bioavailability: Do they correlate?

    PubMed Central

    Musther, Helen; Olivares-Morales, Andrés; Hatley, Oliver J.D.; Liu, Bo; Rostami Hodjegan, Amin

    2014-01-01

    Oral bioavailability is a key consideration in development of drug products, and the use of preclinical species in predicting bioavailability in human has long been debated. In order to clarify whether any correlation between human and animal bioavailability exist, an extensive analysis of the published literature data was conducted. Due to the complex nature of bioavailability calculations inclusion criteria were applied to ensure integrity of the data. A database of 184 compounds was assembled. Linear regression for the reported compounds indicated no strong or predictive correlations to human data for all species, individually and combined. The lack of correlation in this extended dataset highlights that animal bioavailability is not quantitatively predictive of bioavailability in human. Although qualitative (high/low bioavailability) indications might be possible, models taking into account species-specific factors that may affect bioavailability are recommended for developing quantitative prediction. PMID:23988844

  16. Mouse Assay for Determination of Arsenic Bioavailability in Contaminated Soils

    EPA Science Inventory

    Background: Accurate assessment of human exposure estimates from arsenic-contaminated soils depends upon estimating arsenic (As) soil bioavailability. Development of bioavailability assays provides data needed for human health risk assessments and supports development and valida...

  17. Hydroponics: A Versatile System to Study Nutrient Allocation and Plant Responses to Nutrient Availability and Exposure to Toxic Elements.

    PubMed

    Nguyen, Nga T; McInturf, Samuel A; Mendoza-Cózatl, David G

    2016-01-01

    Hydroponic systems have been utilized as one of the standard methods for plant biology research and are also used in commercial production for several crops, including lettuce and tomato. Within the plant research community, numerous hydroponic systems have been designed to study plant responses to biotic and abiotic stresses. Here we present a hydroponic protocol that can be easily implemented in laboratories interested in pursuing studies on plant mineral nutrition. This protocol describes the hydroponic system set up in detail and the preparation of plant material for successful experiments. Most of the materials described in this protocol can be found outside scientific supply companies, making the set up for hydroponic experiments less expensive and convenient. The use of a hydroponic growth system is most advantageous in situations where the nutrient media need to be well controlled and when intact roots need to be harvested for downstream applications. We also demonstrate how nutrient concentrations can be modified to induce plant responses to both essential nutrients and toxic non-essential elements. PMID:27500800

  18. Effects of elevated atmospheric carbon dioxide concentrations on water and acid requirements of soybeans grown in a recirculating hydroponic system

    NASA Technical Reports Server (NTRS)

    Mackowiak, C. L.; Wheeler, R. M.; Lowery, W.; Sager, J. C.

    1990-01-01

    Establishing mass budgets of various crop needs, i.e. water and nutrients, in different environments is essential for the Controlled Ecological Life Support System (CELSS). The effects of CO2 (500 and 1000 umol mol (exp -1)) on water and acid use (for pH control) by soybeans in a recirculating hydroponic system were examined. Plants of cvs. McCall and Pixie were grown for 90 days using the nutrient film technique (NFT) and a nitrate based nutrient solution. System acid use for both CO2 levels peaked near 4 weeks during a phase of rapid vegetative growth, but acid use decreased more rapidly under 500 compared to 1000 umol mol (exp GR) CO2. Total system water use by 500 and 1000 umol mol (exp -1) plants was similar, leaving off at 5 weeks and declining as plants senesced (ca. 9 weeks). However, single leaf transpiration rates were consistently lower at 1000 umol mol (exp -1). The data suggest that high CO2 concentrations increase system acid (and nutrient) use because of increased vegetative growth, which in turn negates the benefit of reduced water use (lower transpiration rates) per unit leaf area.

  19. Cadmium tolerance and accumulation of Elsholtzia argyi origining from a zinc/lead mining site - a hydroponics experiment.

    PubMed

    Li, Siliang; Wang, Fengping; Ru, Mei; Ni, Wuzhong

    2014-01-01

    In this study, a hydroponics experiment was conducted to investigate the characteristics of Cd tolerance and accumulation of Elsholtzia argyi natively growing on the soil with high levels of heavy metals in a Zn/Pb mining site. Seedlings of E. argyi grown for 4 weeks and then were treated with 0(CK), 5,10,15, 20, 25, 30, 40, 50,100 umM Cd for 21 days. Each treatment had three replications. No visual toxic symptoms on shoots of E. argyi were observed at Cd level < or = 50 muM. The results indicated that the dry biomass of each tissue and the whole plants of the treatments with < or =40 umM cadmium were similar to that of the control, implying that E. argyi was a cadmium tolerant plant. The results also showed that the shoot Cd concentration significantly (P < 0.05) increased with the increase in the Cd level in nutrient solution. The shoot Cd concentration of the treatment with 40 umM Cd was as high as 237.9 mg kg(-1), which was higher than 100 mg kg(-1), normally used as the threshold concentration for identifying the Cd hyperaccumulating plant. It could be concluded that E. argyi was a Cd tolerant and accumulating plant species. PMID:24933916

  20. Development and bioavailability assessment of ramipril nanoemulsion formulation.

    PubMed

    Shafiq, Sheikh; Shakeel, Faiyaz; Talegaonkar, Sushma; Ahmad, Farhan J; Khar, Roop K; Ali, Mushir

    2007-05-01

    The objective of our investigation was to design a thermodynamically stable and dilutable nanoemulsion formulation of Ramipril, with minimum surfactant concentration that could improve its solubility, stability and oral bioavailability. Formulations were taken from the o/w nanoemulsion region of phase diagrams, which were subjected to thermodynamic stability and dispersibility tests. The composition of optimized formulation was Sefsol 218 (20% w/w), Tween 80 (18% w/w), Carbitol (18% w/w) and standard buffer solution pH 5 (44% w/w) as oil, surfactant, cosurfactant and aqueous phase, respectively, containing 5 mg of ramipril showing drug release (95%), droplet size (80.9 nm), polydispersity (0.271), viscosity (10.68 cP), and infinite dilution capability. In vitro drug release of the nanoemulsion formulations was highly significant (p<0.01) as compared to marketed capsule formulation and drug suspension. The relative bioavailability of ramipril nanoemulsion to that of conventional capsule form was found to be 229.62% whereas to that of drug suspension was 539.49%. The present study revealed that ramipril nanoemulsion could be used as a liquid formulation for pediatric and geriatric patients and can be formulated as self-nanoemulsifying drug delivery system (SNEDDS) as a unit dosage form. PMID:17127045

  1. Iron bioavailability to phytoplankton: an empirical approach

    PubMed Central

    Lis, Hagar; Shaked, Yeala; Kranzler, Chana; Keren, Nir; Morel, François M M

    2015-01-01

    Phytoplankton are often limited by iron in aquatic environments. Here we examine Fe bioavailability to phytoplankton by analyzing iron uptake from various Fe substrates by several species of phytoplankton grown under conditions of Fe limitation and comparing the measured uptake rate constants (Fe uptake rate/ substrate concentration). When unchelated iron, Fe′, buffered by an excess of the chelating agent EDTA is used as the Fe substrate, the uptake rate constants of all the eukaryotic phytoplankton species are tightly correlated and proportional to their respective surface areas (S.A.). The same is true when FeDFB is the substrate, but the corresponding uptake constants are one thousand times smaller than for Fe′. The uptake rate constants for the other substrates we examined fall mostly between the values for Fe′ and FeDFB for the same S.A. These two model substrates thus empirically define a bioavailability envelope with Fe′ at the upper and FeDFB at the lower limit of iron bioavailability. This envelope provides a convenient framework to compare the relative bioavailabilities of various Fe substrates to eukaryotic phytoplankton and the Fe uptake abilities of different phytoplankton species. Compared with eukaryotic species, cyanobacteria have similar uptake constants for Fe′ but lower ones for FeDFB. The unique relationship between the uptake rate constants and the S.A. of phytoplankton species suggests that the uptake rate constant of Fe-limited phytoplankton has reached a universal upper limit and provides insight into the underlying uptake mechanism. PMID:25350155

  2. Bioavailability and Bioequivalence in Drug Development.

    PubMed

    Chow, Shein-Chung

    2014-01-01

    Bioavailability is referred to as the extent and rate to which the active drug ingredient or active moiety from the drug product is absorbed and becomes available at the site of drug action. The relative bioavailability in terms of the rate and extent of drug absorption is considered predictive of clinical outcomes. In 1984, the United States Food and Drug Administration (FDA) was authorized to approve generic drug products under the Drug Price Competition and Patent Term Restoration Act based on evidence of average bioequivalence in drug absorption through the conduct of bioavailability and bioequivalence studies. This article provides an overview (from an American point of view) of definition of bioavailability and bioequivalence, Fundamental Bioequivalence Assumption, regulatory requirements, and process for bioequivalence assessment of generic drug products. Basic considerations including criteria, study design, power analysis for sample size determination, and the conduct of bioequivalence trial, and statistical methods are provided. Practical issues such as one size-fits-all criterion, drug interchangeability and scaled average criteria for assessment of highly variable drug products are also discussed. PMID:25215170

  3. Enhanced bioavailability of opiates after intratracheal administration

    SciTech Connect

    Findlay, J.W.A.; Jones, E.C.; McNulty, M.J.

    1986-03-01

    Several opiate analgesics have low oral bioavailabilities in the dog because of presystemic metabolism. Intratracheal administration may circumvent this first-pass effect. Three anesthetized beagles received 5-mg/kg doses of codeine phosphate intratracheally (i.t.), orally (p.o.) and intravenously (i.v.) in a crossover study. The following drugs were also studied in similar experiments: ethylmorphine hydrochloride (5 mg/kg), pholcodine bitartrate (10 mg/kg, hydrocodone bitartrate (4 mg/kg) and morphine sulfate (2.5 mg/kg). Plasma drug concentrations over the 24- to 48-hr periods after drug administrations were determined by radioimmunoassays. I.t. bioavailabilities (codeine (84%), ethylmorphine (100%), and morphine (87%)) of drugs with poor oral availabilities were all markedly higher than the corresponding oral values (14, 26, and 23%, respectively). I.t. bioavailabilities of pholcodine (93%) and hydrocodone (92%), which have good oral availabilities (74 and 79%, respectively), were also enhanced. In all cases, peak plasma concentrations occurred more rapidly after i.t. (0.08-0.17 hr) than after oral (0.5-2 hr) dosing and i.t. disposition often resembled i.v. kinetics. I.t. administration may be a valuable alternative dosing route, providing rapid onset of pharmacological activity for potent drugs with poor oral bioavailability.

  4. BIOAVAILABILITY OF CHEMICAL CONTAMINANTS IN AQUATIC SYSTEMS

    EPA Science Inventory

    Before a chemical can elicit toxicity, the animal must accumulate a dose at a target tissue of sufficient magnitude to produce a response. Bioavailability refers to the degree to which this accumulation occurs relative to the amount of chemical present in the environment, and is ...

  5. 21 CFR 320.38 - Retention of bioavailability samples.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... (CONTINUED) DRUGS FOR HUMAN USE BIOAVAILABILITY AND BIOEQUIVALENCE REQUIREMENTS Procedures for Determining the Bioavailability or Bioequivalence of Drug Products § 320.38 Retention of bioavailability samples... standard used to conduct an in vivo bioequivalence study comparing the test article to the...

  6. 21 CFR 320.38 - Retention of bioavailability samples.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... (CONTINUED) DRUGS FOR HUMAN USE BIOAVAILABILITY AND BIOEQUIVALENCE REQUIREMENTS Procedures for Determining the Bioavailability or Bioequivalence of Drug Products § 320.38 Retention of bioavailability samples... standard used to conduct an in vivo bioequivalence study comparing the test article to the...

  7. The sensitivity of an hydroponic lettuce root elongation bioassay to metals, phenol and wastewaters.

    PubMed

    Park, Jihae; Yoon, Jeong-hyun; Depuydt, Stephen; Oh, Jung-Woo; Jo, Youn-min; Kim, Kyungtae; Brown, Murray T; Han, Taejun

    2016-04-01

    The root elongation bioassay is one of the most straightforward test methods used for environmental monitoring in terms of simplicity, rapidity and economy since it merely requires filter paper, distilled water and Petri dishes. However, filter paper as a support material is known to be problematic as it can reduce the sensitivity of the test. The newly developed hydroponic method reported here differs from the conventional root elongation method (US EPA filter paper method) in that no support material is used and the exposure time is shorter (48 h in this test versus 120 h in the US EPA test). For metals, the hydroponic test method was 3.3 (for Hg) to 57 (for Cu) times more sensitive than the US EPA method with the rank orders of sensitivity, estimated from EC50 values, being Cu≥Cd>Ni≥Zn≥Hg for the former and Hg≥Cu≥Ni≥Cd≥Zn for the latter methods. For phenol, the results did not differ significantly; EC50 values were 124 mg L(-1) and 108-180 mg L(-1) for the hydroponic and filter paper methods, respectively. Lettuce was less sensitive than daphnids to wastewaters, but the root elongation response appears to be wastewater-specific and is especially sensitive for detecting the presence of fluorine. The new hydroponic test thus provides many practical advantages, especially in terms of cost and time-effectiveness requiring only a well plate, a small volume of distilled water and short exposure period; furthermore, no specialist expertise is required. The method is simpler than the conventional EPA technique in not using filter paper which can influence the sensitivity of the test. Additionally, plant seeds have a long shelf-life and require little or no maintenance. PMID:26748376

  8. Safety assessment of greenhouse hydroponic tomatoes irrigated with reclaimed and surface water.

    PubMed

    Lopez-Galvez, Francisco; Allende, Ana; Pedrero-Salcedo, Francisco; Alarcon, Juan Jose; Gil, Maria Isabel

    2014-11-17

    The impact of reclaimed and surface water on the microbiological safety of hydroponic tomatoes was assessed. Greenhouse tomatoes were irrigated with reclaimed and surface water and grown on two hydroponic substrates (coconut fiber and rock wool). Water samples (n=208) were taken from irrigation water, with and without the addition of fertilizers and drainage water, and hydroponic tomatoes (n=72). Samples were analyzed for indicator microorganisms, generic Escherichia coli and Listeria spp., and pathogenic bacteria such as Salmonella spp. and Shiga-toxigenic E. coli (STEC), using multiplex real-time PCR (RT-PCR) after enrichment. The correlation between climatological parameters such as temperature and the levels of microorganisms in water samples was also determined. In irrigation water, generic E. coli counts were higher in reclaimed than in surface water whereas Listeria spp. numbers increased after adding the fertilizers in both water sources. In drainage water, no clear differences in E. coli and Listeria numbers were observed between reclaimed and surface water. No positive samples for STEC were found in irrigation water. Presumptive positives for Salmonella spp. were found in 7.7% of the water samples and 62.5% of these samples were reclaimed water. Salmonella-positive samples by RT-PCR could not be confirmed by conventional methods. Higher concentrations of E. coli were associated with Salmonella-presumptive positive samples. Climatological parameters, such as temperature, were not correlated with the E. coli and Listeria spp. counts. Tomato samples were negative for bacterial pathogens, while generic E. coli and Listeria spp. counts were below the detection limit. The prevalence of presumptive Salmonella spp. found in irrigation water (reclaimed and surface water) was high, which might present a risk of contamination. The absence of pathogens on greenhouse hydroponic tomatoes indicates that good agricultural practices (GAP) were in place, avoiding the

  9. The structure and function of microbial communities in recirculating hydroponic systems.

    PubMed

    Garland, J L

    1994-11-01

    Strategies to control the microbial community associated with plant growth systems need to be based on a fundamental understanding of the factors which structure and regulate the community. Spatial and temporal patterns in the abundance and production rate of microorganisms in hydroponic systems containing wheat were examined to evaluate how root-derived carbon is processed. The relevance of results to monitoring and control strategies is discussed. PMID:11540209

  10. The structure and function of microbial communities in recirculating hydroponic systems

    NASA Astrophysics Data System (ADS)

    Garland, J. L.

    1994-11-01

    Strategies to control the microbial community associated with plant growth systems need to be based on a fundamental understanding of the factors which structure and regulate the community. Spatial and temporal patterns in the abundance and production rate of microorganisms in hydroponic systems containing wheat were examined to evaluate how root-derived carbon is processed. The relevance of results to monitoring and control strategies is discussed.

  11. Hydroponic isotope labeling of entire plants and high-performance mass spectrometry for quantitative plant proteomics.

    PubMed

    Bindschedler, Laurence V; Mills, Davinia J S; Cramer, Rainer

    2012-01-01

    Hydroponic isotope labeling of entire plants (HILEP) combines hydroponic plant cultivation and metabolic labeling with stable isotopes using (15)N-containing inorganic salts to label whole and mature plants. Employing (15)N salts as the sole nitrogen source for HILEP leads to the production of healthy-looking plants which contain (15)N proteins labeled to nearly 100%. Therefore, HILEP is suitable for quantitative plant proteomic analysis, where plants are grown in either (14)N- or (15)N-hydroponic media and pooled when the biological samples are collected for relative proteome quantitation. The pooled (14)N-/(15)N-protein extracts can be fractionated in any suitable way and digested with a protease for shotgun proteomics, using typically reverse phase liquid chromatography nanoelectrospray ionization tandem mass spectrometry (RPLC-nESI-MS/MS). Best results were obtained with a hybrid ion trap/FT-MS mass spectrometer, combining high mass accuracy and sensitivity for the MS data acquisition with speed and high-throughput MS/MS data acquisition, increasing the number of proteins identified and quantified and improving protein quantitation. Peak processing and picking from raw MS data files, protein identification, and quantitation were performed in a highly automated way using integrated MS data analysis software with minimum manual intervention, thus easing the analytical workflow. In this methodology paper, we describe how to grow Arabidopsis plants hydroponically for isotope labeling using (15)N salts and how to quantitate the resulting proteomes using a convenient workflow that does not require extensive bioinformatics skills. PMID:22665301

  12. Effect of pomegranate pretreatment on the oral bioavailability of buspirone in male albino rabbits

    PubMed Central

    Shravan Kumar, Y.; Adukondalu, D.; Bhargavi Latha, A.; Vamshi Vishnu, Y.; Ramesh, G.; Shiva Kumar, R.; Sarangapani, M.

    2011-01-01

    Back ground and the purpose of study Many drug substances and variety of naturally occurring dietary or herbal components are capable of interaction with the CYP enzyme system. The aim of the study was to investigate the effect of pomegranate juice pretreatment on the bioavailability of buspirone in rabbits. Methods White New Zealand rabbits weighing 2.1±0.13 Kg were selected for study. The bioavailability of buspirone after pre-treatment with pomegranate juice (10 ml Kg−1 for seven days) was compared with an oral solution of 10 mg kg−1 of buspirone in distilled water. Animals were allowed free access to food and water, until night prior to dosing and were fasted for 10 hrs. In the first phase oral solution (10 mg kg−1) was administered through feeding tube followed by rinsing with 10 ml of water. In the second phase, the group was pretreated with pomegranate juice for 7 days and study was conducted after 15 days of washout period. Results and conclusion The results showed that there was a significant (p<0.05) difference in the bioavailability of buspirone after pre-treatment with pomegranate juice.This increase in bioavailability might be due to inhibition of CYP3A4. Further studies are required to prove this mechanism in humans. PMID:22615667

  13. Effects of hypertonic buffer composition on lymph node uptake and bioavailability of rituximab, after subcutaneous administration

    PubMed Central

    Fathallah, Anas M.; Turner, Michael R.; Balu-Iyer, Sathy V.

    2015-01-01

    Subcutaneous administration of biologics is highly desirable; however, incomplete bioavailability after sc administration remains a major challenge. In this work we investigated the effects of excipient dependent hyper-osmolarity on lymphatic uptake and plasma exposure of rituximab as a model protein. Using Swiss Webster (SW) mice as our animal model, we compared the effects of NaCl, mannitol and, O-Phospho-L-Serine (OPLS) on plasma concentration of rituximab over 5 days after sc administration. We observed an increase in plasma concentrations in animals administered rituximab in hypertonic buffer solutions, as compared to isotonic buffer. Bioavailability, as estimated by our pharmacokinetic model, increased from 29% in isotonic buffer to 54% in hypertonic buffer containing NaCl, to almost complete bioavailability in hypertonic buffers containing high dose OPLS or mannitol. This improvement in plasma exposure is due to improved lymphatic trafficking as evident from the increase in the fraction of dose trafficked through the lymph node in the presence of hypertonic buffers. The fraction of the dose trafficked through the lymphatic, as estimated by the model, increased from 0.05 % in isotonic buffer to 13% in hyper-tonic buffer containing NaCl to about 30% for hypertonic buffers containing high dose OPLS and mannitol. Our data suggests that hypertonic solutions may be a viable option to improve sc bioavailability. PMID:25377184

  14. Continuous hydroponic wheat production using a recirculating system

    NASA Technical Reports Server (NTRS)

    Mackowiak, C. L.; Owens, L. P.; Hinkle, C. R.; Prince, R. P.

    1989-01-01

    Continuous crop production, where plants of various ages are growing simultaneously in a single recirculating nutrient solution, is a possible alternative to batch production in a Controlled Ecological Life Support System. A study was conducted at John F. Kennedy Space Center where 8 trays (0.24 sq m per tray) of Triticum aestivum L. Yecora Rojo were grown simultaneously in a growth chamber at 23 C, 65 percent relative humidity, 1000 ppm CO2, continuous light, with a continuous flow, thin film nutrient delivery system. The same modified Hoagland nutrient solution was recirculated through the plant trays from an 80 L reservoir throughout the study. It was maintained by periodic addition of water and nutrients based on chemical analyses of the solution. The study was conducted for 216 days, during which 24 trays of wheat were consecutively planted (one every 9 days), 16 of which were grown to maturity and harvested. The remaining 8 trays were harvested on day 216. Grain yields averaged 520 g m(exp -2), and had an average edible biomass of 32 percent. Consecutive yields were unaffected by nutrient solution age. It was concluded that continual wheat production will work in this system over an extended period of time. Certain micronutrient deficiencies and toxicities posed problems and must be addressed in future continuous production systems.

  15. Thiol-Based Selective Extraction Assay to Comparatively Assess Bioavailable Mercury in Sediments

    PubMed Central

    Ticknor, Jonathan L.; Kucharzyk, Katarzyna H.; Porter, Kaitlyn A.; Deshusses, Marc A.; Hsu-Kim, Heileen

    2015-01-01

    Abstract Bioaccumulation of methylmercury in the aquatic food web is governed in part by the methylation of inorganic divalent mercury (Hg(II)) by anaerobic microorganisms. In sulfidic settings, a small fraction of total Hg(II) is typically bioavailable to methylating microorganisms. Quantification of this fraction is difficult due to uncertainties in the speciation of Hg(II) and the mechanisms of uptake by methylating microbes. However, recent studies have shown that the bioavailable fraction is likely to include a portion of Hg(II) associated with solid phases, that is, nanostructured mercuric sulfides. Moreover, addition of thiols to suspensions of methylating cultures coincides with increased uptake into cells and methylmercury production. Here, we present a thiol-based selective extraction assay to provide information on the bioavailable Hg fraction in sediments. In the procedure, sediment samples were exposed to a nitrogen-purged solution of glutathione (GSH) for 30 min and the amount of GSH-leachable mercury was quantified. In nine sediment samples from a marine location, the relative GSH-leachable mercury concentration was strongly correlated to the relative amount of methylmercury in the sediments (r2=0.91, p<0.0001) across an order of magnitude of methylmercury concentration values. The approach was further applied to anaerobic sediment slurry microcosm experiments in which sediments were cultured under the same microbial growth conditions but were amended with multiple forms of Hg with a known spectrum of bioavailability. GSH-leachable Hg concentrations increased with observed methylmercury concentrations in the microcosms, matching the trend of species bioavailability in our previous work. Results suggest that a thiol-based selective leaching approach is an improvement compared with other proposed methods to assess Hg bioavailability in sediment and that this approach could provide a basis for comparison of sites where Hg methylation is a concern

  16. Evaluation of a nanoemulsion formulation strategy for oral bioavailability enhancement of danazol in rats and dogs.

    PubMed

    Devalapally, Harikrishna; Silchenko, Svitlana; Zhou, Feng; McDade, Jessica; Goloverda, Galina; Owen, Albert; Hidalgo, Ismael J

    2013-10-01

    The objective of this study was to determine whether nanoemulsion formulations constitute a viable strategy to improve the oral bioavailability of danazol, a compound whose poor aqueous solubility limits its oral bioavailability. Danazol-containing oil-in-water nanoemulsions (NE) with and without cosurfactants stearylamine (SA) and deoxycholic acid (DCA) were prepared and characterized. Nanoemulsion droplets size ranging from 238 to 344 nm and with surface charges of -24.8 mV (NE), -26.5 mV (NE-DCA), and +27.8 mV (NE-SA) were reproducibly obtained. Oral bioavailability of danazol in nanoemulsions was compared with other vehicles such as PEG400, 1% methylcellulose (MC) in water (1% MC), Labrafil, and a Labrafil/Tween 80 (9:1) mixture, after intragastric administration to rats and after oral administration of NE-SA, a Labrafil solution, or a Danocrine® tablet to dogs. The absolute bioavailability of danazol was 0.6% (PEG400), 1.2% (1% MC), 6.0% (Labrafil), 7.5% (Labrafil/Tween80), 8.1% (NE-DCA), 14.8% (NE), and 17.4% (NE-SA) in rats, and 0.24% (Danocrine), 6.2% (Labrafil), and 58.7% (NE-SA) in dogs. Overall, danazol bioavailability in any nanoemulsion was higher than any other formulation. Danazol bioavailability from NE and NE-SA was 1.8- to 2.2-fold higher than NE-DCA nanoemulsion and could be due to significant difference in droplet size. PMID:23878097

  17. Evaluation of a Nanoemulsion Formulation Strategy for Oral Bioavailability Enhancement of Danazol in Rats and Dogs

    PubMed Central

    Devalapally, Harikrishna; Silchenko, Svitlana; Zhou, Feng; McDade, Jessica; Goloverda, Galina; Owen, Albert; Hidalgo, Ismael J.

    2013-01-01

    The objective of this study was to determine whether nanoemulsion formulations constitute a viable strategy to improve the oral bioavailability of danazol, a compound whose poor aqueous solubility limits its oral bioavailability. Danazol-containing oil-in-water nanoemulsions (NE) with and without co-surfactants stearylamine (SA) and deoxycholic acid (DCA) were prepared and characterized. Nanoemulsion droplets size ranging from 238 to 344 nm and with surface charges of −24.8 mV (NE), −26.5 mV (NE-DCA), and +27.8 mV (NE-SA) were reproducibly obtained. Oral bioavailability of danazol in nanoemulsions was compared with other vehicles such as, PEG400, 1% methylcellulose in water (1% MC), Labrafil, and a Labrafil/Tween 80 (9:1) mixture, after intragastric administration to rats and after oral administration of NE-SA, a Labrafil solution, or a Danocrine® tablet to dogs. The absolute bioavailability of danazol was 0.6% (PEG400), 1.2% (1% MC), 6.0% (Labrafil), 7.5% (Labrafil/Tween80), 8.1% (NE-DCA), 14.8% (NE), and 17.4% (NE-SA) in rats, and 0.24% (Danocrine), 6.2% (Labrafil), and 58.7% (NE-SA) in dogs. Overall, danazol bioavailability in any nanoemulsion was higher than any other formulation. Danazol bioavailability from NE and NE-SA was 1.8 to 2.2-fold higher than NE-DCA nanoemulsion and could be due to significant difference in droplet size. PMID:23878097

  18. Detection of nitrogen deficiency QTL in juvenile wild barley introgression lines growing in a hydroponic system

    PubMed Central

    2012-01-01

    Background In this report we studied the genetic regulation of juvenile development of wild barley introgression lines (S42ILs) under two contrasting hydroponic nitrogen (N) supplies. Ten shoot and root related traits were examined among 42 S42ILs and the recurrent parent ‘Scarlett’. The traits included tiller number, leaf number, plant height, leaf and root length, leaf to root length ratio, shoots and root dry weight, shoot to root weight ratio, and chlorophyll content. Our aims were (1) to test the suitability of a hydroponic system for early detection of favourable S42ILs, (2) to locate quantitative trait loci (QTL) that control the examined traits, (3) to identify favourable wild barley alleles that improve trait performances in regard to N treatment and, finally, (4) to validate the identified QTL through comparison with previously reported QTL originating from the same parental cross. Results The phenotypic data were analysed in a mixed model association study to detect QTL. The post-hoc Dunnett test identified 28 S42ILs that revealed significant (P < 0.01) effects for at least one trait. Forty-three, 41 and 42 S42ILs revealed effects across both N treatments, under low N and under high N treatment, respectively. Due to overlapping or flanking wild barley introgressions of the S42ILs, these associations were summarised to 58 QTL. In total, 12 QTL of the hydroponic N study corresponded to QTL that were also detected in field trials with adult plants of a similar S42IL set or of the original S42 population. For instance, S42IL-135, -136 and -137, revealed increasing Hsp effects for tiller number, leaf number, leaf length, plant height and leaf to root ratio on the long arm of chromosome 7H. These QTL correspond to QTL for ears per plant and plant height that were previously detected in field trials conducted with the same S42ILs or with the S42 population. Conclusion Our results suggest that the QTL we identified under hydroponic N cultivation partly

  19. Bloat free genetic programming: application to human oral bioavailability prediction.

    PubMed

    Silva, Sara; Vanneschi, Leonardo

    2012-01-01

    Being able to predict the human oral bioavailability for a potential new drug is extremely important for the drug discovery process. This problem has been addressed by several prediction tools, with Genetic Programming providing some of the best results ever achieved. In this paper we use the newest developments of Genetic Programming, in particular the latest bloat control method, Operator Equalisation, to find out how much improvement we can achieve on this problem. We show examples of some actual solutions and discuss their quality, comparing them with previously published results. We identify some unexpected behaviours related to overfitting, and discuss the way for further improving the practical usage of the Genetic Programming approach. PMID:23356009

  20. The Vacuum-Operated Nutrient Delivery System: hydroponics for microgravity.

    PubMed

    Brown, C S; Cox, W M; Dreschel, T W; Chetirkin, P V

    1992-11-01

    A nutrient delivery system that may have applicability for growing plants in microgravity is described. The Vacuum-Operated Nutrient Delivery System (VONDS) draws nutrient solution across roots that are under a partial vacuum at approximately 91 kPa. Bean (Phaseolus vulgaris L. cv. Blue Lake 274) plants grown on the VONDS had consistently greater leaf area and higher root, stem, leaf, and pod dry weights than plants grown under nonvacuum control conditions. This study demonstrates the potential applicability of the VONDS for growing plants in microgravity for space biology experimentation and/or crop production. PMID:11537607

  1. Oral bioavailability of curcumin: problems and advancements.

    PubMed

    Liu, Weidong; Zhai, Yingjie; Heng, Xueyuan; Che, Feng Yuan; Chen, Wenjun; Sun, Dezhong; Zhai, Guangxi

    2016-09-01

    Curcumin is a natural compound of Curcuma longa L. and has shown many pharmacological activities such as anti-inflammatory, anti-oxidant in both preclinical and clinical studies. Moreover, curcumin has hepatoprotective, neuroprotective activities and protects against myocardial infarction. Particularly, curcumin has also demonstrated favorite anticancer efficacy. But limiting factors such as its extremely low oral bioavailability hampers its application as therapeutic agent. Therefore, many technologies have been developed and applied to overcome this limitation. This review described the main physicochemical properties of curcumin and summarized the recent studies in the design and development of oral delivery systems for curcumin to enhance the solubility and oral bioavailability, including liposomes, nanoparticles and polymeric micelles, phospholipid complexes, and microemulsions. PMID:26942997

  2. Bioavailability of tocotrienols: evidence in human studies

    PubMed Central

    2014-01-01

    As a minor component of vitamin E, tocotrienols were evident in exhibiting biological activities such as neuroprotection, radio-protection, anti-cancer, anti-inflammatory and lipid lowering properties which are not shared by tocopherols. However, available data on the therapeutic window of tocotrienols remains controversial. It is important to understand the absorption and bioavailability mechanisms before conducting in-depth investigations into the therapeutic efficacy of tocotrienols in humans. In this review, we updated current evidence on the bioavailability of tocotrienols from human studies. Available data from five studies suggested that tocotrienols may reach its target destination through an alternative pathway despite its low affinity for α-tocopherol transfer protein. This was evident when studies reported considerable amount of tocotrienols detected in HDL particles and adipose tissues after oral consumption. Besides, plasma concentrations of tocotrienols were shown to be higher when administered with food while self-emulsifying preparation of tocotrienols was shown to enhance the absorption of tocotrienols. Nevertheless, mixed results were observed based on the outcome from 24 clinical studies, focusing on the dosages, study populations and formulations used. This may be due to the variation of compositions and dosages of tocotrienols used, suggesting a need to understand the formulation of tocotrienols in the study design. Essentially, implementation of a control diet such as AHA Step 1 diet may influence the study outcomes, especially in hypercholesterolemic subjects when lipid profile might be modified due to synergistic interaction between tocotrienols and control diet. We also found that the bioavailability of tocotrienols were inconsistent in different target populations, from healthy subjects to smokers and diseased patients. In this review, the effect of dosage, composition and formulation of tocotrienols as well as study populations on the

  3. Speciation and microalgal bioavailability of inorganic silver

    SciTech Connect

    Reinfelder, J.R.; Chang, S.I.

    1999-06-01

    Silver accumulation in aquatic organisms is primarily attributed to the bioavailability of the free Ag ion (Ag{sup +}). Some reports suggest that AgCl(aq) is also available for biological uptake, but few studies of Ag bioavailability used the range of chloride concentrations over which AgCl{sup 0}(aq) is the dominant Ag species. None used environmentally realistic, low Ag concentrations. To assess the bioavailability of inorganic Ag species and the importance of the low polarity AgCl(aq) complex to biological uptake, the authors determined the octanol-water partition coefficient of Ag over a range of chloride concentrations representative of fresh to brackish waters and measured short-term Ag uptake rates in the euryhaline marine microalga Thalassiosira weissflogii exposed to a total silver concentration of 50 pM. Overall octanol-water partition coefficients (D{sub ow}) of inorganic silver ranged from 0.02 to 0.06. The K{sub ow} of AgCl(aq) calculated using D{sub ow} values measured at 0.5, 5, and 50 mM Cl{sup {minus}} and the K{sub ow} of Ag{sup +} (0.03, measured in the absence of Cl{sup {minus}}) was 0.09. Silver D{sub ow} and uptake rate constants in phytoplankton were highest at the Cl{sup {minus}} concentration where uncharged AgCl(aq) is the dominant silver species. Their results demonstrate that AgCl(aq) is the principal bioavailable species of inorganic silver in phytoplankton and suggest that direct uptake of AgCl(aq) is important to the overall accumulation of Ag in aquatic invertebrates.

  4. Potassium Intake, Bioavailability, Hypertension, and Glucose Control

    PubMed Central

    Stone, Michael S.; Martyn, Lisa; Weaver, Connie M.

    2016-01-01

    Potassium is an essential nutrient. It is the most abundant cation in intracellular fluid where it plays a key role in maintaining cell function. The gradient of potassium across the cell membrane determines cellular membrane potential, which is maintained in large part by the ubiquitous ion channel the sodium-potassium (Na+-K+) ATPase pump. Approximately 90% of potassium consumed (60–100 mEq) is lost in the urine, with the other 10% excreted in the stool, and a very small amount lost in sweat. Little is known about the bioavailability of potassium, especially from dietary sources. Less is understood on how bioavailability may affect health outcomes. Hypertension (HTN) is the leading cause of cardiovascular disease (CVD) and a major financial burden ($50.6 billion) to the US public health system, and has a significant impact on all-cause morbidity and mortality worldwide. The relationship between increased potassium supplementation and a decrease in HTN is relatively well understood, but the effect of increased potassium intake from dietary sources on blood pressure overall is less clear. In addition, treatment options for hypertensive individuals (e.g., thiazide diuretics) may further compound chronic disease risk via impairments in potassium utilization and glucose control. Understanding potassium bioavailability from various sources may help to reveal how specific compounds and tissues influence potassium movement, and further the understanding of its role in health. PMID:27455317

  5. Bioavailability and biodistribution of nanodelivered lutein.

    PubMed

    Kamil, Alison; Smith, Donald E; Blumberg, Jeffrey B; Astete, Carlos; Sabliov, Cristina; Oliver Chen, C-Y

    2016-02-01

    The aim of the study was to evaluate the ability of poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NP) to enhance lutein bioavailability. The bioavailability of free lutein and PLGA-NP lutein in rats was assessed by determining plasma pharmacokinetics and deposition in selected tissues. Lutein uptake and secretion was also assessed in Caco-2 cells. Compared to free lutein, PLGA-NP increased the maximal plasma concentration (Cmax) and area under the time-concentration curve in rats by 54.5- and 77.6-fold, respectively, while promoting tissue accumulation in the mesenteric fat and spleen. In comparison with micellized lutein, PLGA-NP lutein improved the Cmax in rat plasma by 15.6-fold and in selected tissues by ⩾ 3.8-fold. In contrast, PLGA-NP lutein had a lower uptake and secretion of lutein in Caco-2 cells by 10.0- and 50.5-fold, respectively, compared to micellized lutein. In conclusion, delivery of lutein with polymeric NP may be an approach to improve the bioavailability of lutein in vivo. PMID:26304429

  6. Relative bioavailability of three cefixime formulations.

    PubMed

    Kees, F; Naber, K G; Sigl, G; Ungethüm, W; Grobecker, H

    1990-03-01

    Three galenic formulations of cefixime (tablet, syrup and dry suspension) containing 200 mg each were compared with respect to their relative bioavailability in twelve healthy volunteers. All three formulations showed reliable absorption. Mean peak plasma concentrations were reached after 3.3-3.5 h, mean terminal half lives were 2.9-3.1 h. 18-24% of the dose administered were recovered unchanged in the urine. Best bioavailability was obtained with the dry suspension (AUC0-infinity = 25.8 +/- 7.0 micrograms/ml h; Cmax = 3.4 +/- 0.9 microgram/ml), followed by the tablet (AUC0-infinity = 20.9 +/- 8.1 micrograms/ml h; Cmax = 3.0 +/- 1.0 micrograms/ml) and the syrup which is based on triglycerides (AUC0-infinity = 17.8 +/- 5.9 micrograms/ml h; Cmax = 2.4 +/- 0.7 micrograms/ml). The statistical analysis resulted in bioinequivalence between dry suspension and syrup. It is concluded that best bioavailability of cefixime after oral administration is guaranteed when taken in an "aqueous medium" either as dry suspension or as tablet with "plenty of liquid". PMID:2346538

  7. Potassium Intake, Bioavailability, Hypertension, and Glucose Control.

    PubMed

    Stone, Michael S; Martyn, Lisa; Weaver, Connie M

    2016-01-01

    Potassium is an essential nutrient. It is the most abundant cation in intracellular fluid where it plays a key role in maintaining cell function. The gradient of potassium across the cell membrane determines cellular membrane potential, which is maintained in large part by the ubiquitous ion channel the sodium-potassium (Na+-K+) ATPase pump. Approximately 90% of potassium consumed (60-100 mEq) is lost in the urine, with the other 10% excreted in the stool, and a very small amount lost in sweat. Little is known about the bioavailability of potassium, especially from dietary sources. Less is understood on how bioavailability may affect health outcomes. Hypertension (HTN) is the leading cause of cardiovascular disease (CVD) and a major financial burden ($50.6 billion) to the US public health system, and has a significant impact on all-cause morbidity and mortality worldwide. The relationship between increased potassium supplementation and a decrease in HTN is relatively well understood, but the effect of increased potassium intake from dietary sources on blood pressure overall is less clear. In addition, treatment options for hypertensive individuals (e.g., thiazide diuretics) may further compound chronic disease risk via impairments in potassium utilization and glucose control. Understanding potassium bioavailability from various sources may help to reveal how specific compounds and tissues influence potassium movement, and further the understanding of its role in health. PMID:27455317

  8. Bioavailability of nanoparticulate hematite to Arabidopsis thaliana.

    PubMed

    Marusenko, Yevgeniy; Shipp, Jessie; Hamilton, George A; Morgan, Jennifer L L; Keebaugh, Michael; Hill, Hansina; Dutta, Arnab; Zhuo, Xiaoding; Upadhyay, Nabin; Hutchings, James; Herckes, Pierre; Anbar, Ariel D; Shock, Everett; Hartnett, Hilairy E

    2013-03-01

    The environmental effects and bioavailability of nanoparticulate iron (Fe) to plants are currently unknown. Here, plant bioavailability of synthesized hematite Fe nanoparticles was evaluated using Arabidopsis thaliana (A. thaliana) as a model. Over 56-days of growing wild-type A. thaliana, the nanoparticle-Fe and no-Fe treatments had lower plant biomass, lower chlorophyll concentrations, and lower internal Fe concentrations than the Fe-treatment. Results for the no-Fe and nanoparticle-Fe treatments were consistently similar throughout the experiment. These results suggest that nanoparticles (mean diameter 40.9 nm, range 22.3-67.0 nm) were not taken up and therefore not bioavailable to A. thaliana. Over 14-days growing wild-type and transgenic (Type I/II proton pump overexpression) A. thaliana, the Type I plant grew more than the wild-type in the nanoparticle-Fe treatment, suggesting Type I plants cope better with Fe limitation; however, the nanoparticle-Fe and no-Fe treatments had similar growth for all plant types. PMID:23262070

  9. Selenium bioavailability with reference to human nutrition

    SciTech Connect

    Young, V.R.; Nahapetian, A.; Janghorbani, M.

    1982-05-01

    Various aspects of selenium metabolism and nutrition in relation to the question of selenium bioavailability in foods and the diet of man are reviewed. Few published studies exist on selenium metabolism in human subjects, particularly those representative of healthy individuals in the United States. Animal studies reveal that various factors, including the source and chemical form of selenium in foods and feeds, influence selenium bioavailability. However, the quantitative significance of animal assay data for human nutrition is not known. The limited number of published studies in man suggest that the metabolic fate and physiological function of dietary selenite may differ from that of selenomethionine or of food selenium. However, much additional research will be required to establish an adequate picture of the significance of dietary selenium bioavailability in human nutrition and health. Based on initial human experiments carried out at the Massachusetts Institute of Technology, use of stable isotopes of selenium offers promising opportunities for closing the gap of knowledge that now exists concerning the role and significance of factors that determine how the selenium present in foods is used to meet the physiological requirements of the consumer.

  10. Rapid screening assay for calcium bioavailability studies

    SciTech Connect

    Luhrsen, K.R.; Hudepohl, G.R.; Smith, K.T.

    1986-03-01

    Calcium bioavailability has been studied by numerous techniques. The authors report here the use of the gamma emitting isotope of calcium (/sup 47/Ca) in a whole body retention assay system. In this system, calcium sources are administered by oral gavage and subsequent counts are determined and corrected for isotopic decay. Unlike iron and zinc retention curves, which exhibit a 2-3 day equilibration period, calcium reaches equilibration after 24 hours. Autoradiographic analysis of the femurs indicate that the newly absorbed calcium is rapidly distributed to the skeletal system. Moreover, the isotope is distributed along the entire bone. Comparisons of calcium bioavailability were made using intrinsic/extrinsic labeled milk from two species i.e. rat and goat as well as CaCO/sub 3/. In addition, extrinsic labeled cow milk was examined. In the rat, the extrinsic labeled calcium from milk was better absorbed than the intrinsic calcium. This was not the case in goat milk or the calcium carbonate which exhibited no significant differences. Chromatographic analysis of the labeled milk indicates a difference in distribution of the /sup 47/Ca. From these data, the authors recommend the use of this assay system in calcium bioavailability studies. The labeling studies and comparisons indicate caution should be used, however, in labeling techniques and species milk comparison.

  11. Nitrofurantoin enteric pellets with high bioavailability based on aciform crystalline formation by wet milling.

    PubMed

    Yu, Hongxia; Pan, Lei; Li, Pucheng; Zhang, Keru; Lin, Xia; Zhang, Yu; Tang, Xing

    2015-06-01

    The aim of the present study was to grind nitrofurantoin (NF) with HPMC solution and to determine the dissolution and bioavailability of the enteric pellets prepared with the NF cogrounds and other excipients. During milling, crystalline transformation occurred--the aciform microcrystalline monohydrate II replaced the coarse crystal anhydrate β and the particle size markedly reduced. In vitro test demonstrated that the enteric pellets prepared with NF cogrounds (4 h) revealed a faster dissolution than the commercial tablet and 50% was released within 30 min in the basic medium. Finally, an in vivo test was conducted in beagle dogs. The Cmax and AUC(0 → 24) of the pellets were 2.19 ± 0.74 μg/ml and 6.73 ± 4.71 μg/ml h, respectively, while the corresponding values were 0.49 ± 0.42 μg/ml and 1.38 ± 1.17 μg/ml h for the tablet. Thus, the bioavailability of the pellets was increased significantly. In conclusion, the wet grinding that reduced the particle size and created the microcrystalline played a major role in the acceleration of the dissolution of NF and, consequently, enhanced the bioavailability, and the wet grinding process offers an alternative approach to improve the dissolution and bioavailability of drugs with poor aqueous solubility. PMID:24467214

  12. An in vitro gastrointestinal method to estimate bioavailable arsenic in contaminated soils and solid media

    SciTech Connect

    Rodriguez, R.R.; Basta, N.T.; Casteel, S.W.; Pace, L.W.

    1999-02-15

    A method was developed to simulate the human gastrointestinal environment and to estimate bioavailability of arsenic in contaminated soil and soil media. In this in vitro gastrointestinal (IVG) method, arsenic is sequentially extracted from contaminated soil with simulated gastric and intestinal solutions. A modified IVG-AB method, where iron hydroxide gel is used to simulate the absorption of arsenic, was also evaluated. Fifteen contaminated soils collected from mining/smelter sites ranging from 401 to 17,460 mg As kg{sup {minus}1} were analyzed. In vitro results were compared with in vivo relative bioavailable arsenic (RBA) determined from dosing trials using immature swine which ranged from 2.7 to 42.8% RBA. Arsenic extracted by the IVG and IVG-AB methods was not statistically different than RBA arsenic measured by the in vivo method. Arsenic extracted by the IVG stomach and intestinal phases was linearly correlated with in vivo arsenic. Similarly, the IVG-AB method was linearly correlated with in vivo bioavailable arsenic. All IVG methods extracted similar amounts of arsenic and provided estimates of bioavailable As in contaminated media. The IVG method may aid in the design and cost-effectiveness of remedial strategies of arsenic-contaminated sites.

  13. Effect of reactive core mat application on bioavailability of hydrophobic organic compounds

    PubMed Central

    Meric, Dogus; Barbuto, Sara M.; Alshawabkeh, Akram N.; Shine, James P.; Sheahan, Thomas C.

    2014-01-01

    Sediment remediation techniques to limit the bioavailability of contaminants are of special interest due to related acute or chronic toxicities associated with sediment contaminants. Bioavailability in aquatic sediments can be particularly problematic due to their accessibility to food chain biota, and interactions with surface and ground water. The effect of a reactive core mat (RCM) containing organoclay on the bioavailability of hydrophobic organic compounds (HOCs) (i.e., PCBs and naphthalene) was studied using oligochaete worms (Lumbriculus variegatus). Sediment sampled from the Neponset River (Milton, MA) with 10 ppm background PCB contamination was used in the experimental study. The objective of this study is to investigate the difference in HOC concentration of worms exposed to: a) a grab sample of contaminated sediment (10.4% total organic carbon); and b) an initially clean mixture of sand and organic matter (the so-called biouptake layer), placed on top of the RCM-capped sediment during consolidation coupled solute transport experiments. In addition to the experimental data, the U.S. Army Corps of Engineers (USACE) biota-sediment accumulation factor (BSAF) database was validated and used to model biouptake of contaminants for certain cases. Results indicate that RCM capping reduced the average bioavailability of both PCBs and naphthalene by a factor of about 50. In fact, worms exposed to the RCM-protected biouptake layer show virtually the same HOC concentrations as those measured in the control worm samples. PMID:22386995

  14. Sugars increase non-heme iron bioavailability in human epithelial intestinal and liver cells.

    PubMed

    Christides, Tatiana; Sharp, Paul

    2013-01-01

    Previous studies have suggested that sugars enhance iron bioavailability, possibly through either chelation or altering the oxidation state of the metal, however, results have been inconclusive. Sugar intake in the last 20 years has increased dramatically, and iron status disorders are significant public health problems worldwide; therefore understanding the nutritional implications of iron-sugar interactions is particularly relevant. In this study we measured the effects of sugars on non-heme iron bioavailability in human intestinal Caco-2 cells and HepG2 hepatoma cells using ferritin formation as a surrogate marker for iron uptake. The effect of sugars on iron oxidation state was examined by measuring ferrous iron formation in different sugar-iron solutions with a ferrozine-based assay. Fructose significantly increased iron-induced ferritin formation in both Caco-2 and HepG2 cells. In addition, high-fructose corn syrup (HFCS-55) increased Caco-2 cell iron-induced ferritin; these effects were negated by the addition of either tannic acid or phytic acid. Fructose combined with FeCl3 increased ferrozine-chelatable ferrous iron levels by approximately 300%. In conclusion, fructose increases iron bioavailability in human intestinal Caco-2 and HepG2 cells. Given the large amount of simple and rapidly digestible sugars in the modern diet their effects on iron bioavailability may have important patho-physiological consequences. Further studies are warranted to characterize these interactions. PMID:24340076

  15. Dynamics of microorganism populations in recirculating nutrient solutions

    NASA Astrophysics Data System (ADS)

    Strayer, R. F.

    1994-11-01

    This overview covers the basic microbial ecology of recirculating hydroponic solutions. Examples from NASA and Soviet CELSS tests and the commercial hydroponic industry will be used. The sources of microorganisms in nutrient solutions include air, water, seeds, plant containers and plumbing, biological vectors, and personnel. Microbial fates include growth, death, and emigration. Important microbial habitats within nutrient delivery systems are root surfaces, hardware surfaces (biofilms), and solution suspension. Numbers of bacteria on root surfaces usually exceed those from the other habitats by several orders of magnitude. Gram negative bacteria dominate the microflora with fungal counts usually much lower. Trends typically show a decrease in counts with increasing time unless stressed plants increase root exudates. Important microbial activities include carbon mineralization and nitrogen transformations. Important detrimental interactions include competition with plants, and human and plant pathogenesis.

  16. Dynamics of microorganism populations in recirculating nutrient solutions.

    PubMed

    Strayer, R F

    1994-11-01

    This overview covers the basic microbial ecology of recirculating hydroponic solutions. Examples from NASA and Soviet CELSS tests and the commercial hydroponic industry will be used. The sources of microorganisms in nutrient solutions include air, water, seeds, plant containers and plumbing, biological vectors, and personnel. Microbial fates include growth, death, and emigration. Important microbial habitats within nutrient delivery systems are root surfaces, hardware surfaces (biofilms), and solution suspension. Numbers of bacteria on root surfaces usually exceed those from the other habitats by several orders of magnitude. Gram negative bacteria dominate the microflora with fungal counts usually much lower. Trends typically show a decrease in counts with increasing time unless stressed plants increase root exudates. Important microbial activities include carbon mineralization and nitrogen transformations. Important detrimental interactions include competition with plants, and human and plant pathogenesis. PMID:11540206

  17. Dynamics of microorganism populations in recirculating nutrient solutions

    NASA Technical Reports Server (NTRS)

    Strayer, R. F.

    1994-01-01

    This overview covers the basic microbial ecology of recirculating hydroponic solutions. Examples from NASA and Soviet Controlled Ecological Life Support Systems (CELSS) tests and the commercial hydroponic industry will be used. The sources of microorganisms in nutrient solutions include air, water, seeds, plant containers and plumbing, biological vectors, and personnel. Microbial fates include growth, death, and emigration. Important microbial habitats within nutrient delivery systems are root surfaces, hardware surfaces (biofilms), and solution suspension. Numbers of bacteria on root surfaces usually exceed those from the other habitats by several orders of magnitude. Gram negative bacteria dominate the microflora with fungal counts usually much lower. Trends typically show a decrease in counts with increasing time unless stressed plants increase root exudates. Important microbial activities include carbon mineralization and nitrogen transformations. Important detrimental interactions include competition with plants, and human and plant pathogenesis.

  18. Dynamics of microorganism populations in recirculating nutrient solutions

    NASA Technical Reports Server (NTRS)

    Strayer, R. F.

    1994-01-01

    This overview covers the basic microbial ecology of recirculating hydroponic solutions. Examples from NASA and Soviet CELSS tests and the commercial hydroponic industry will be used. The sources of microorganisms in nutrient solutions include air, water, seeds, plant containers and plumbing, biological vectors, and personnel. Microbial fates include growth, death, and emigration. Important microbial habitats within nutrient delivery systems are root surfaces, hardware surfaces (biofilms), and solution suspension. Numbers of bacteria on root surfaces usually exceed those from the other habitats by several orders of magnitude. Gram negative bacteria dominate the microflora with fungal counts usually much lower. Trends typically show a decrease in counts with increasing time unless stressed plants increase root exudates. Important microbial activities include carbon mineralization and nitrogen transformations. Important detrimental interactions include competition with plants, and human and plant pathogenesis.

  19. Heavy metal bioavailability and chelate mobilization efficiency in an assisted phytoextraction process.

    PubMed

    Cao, Alessia; Cappai, Giovanna; Carucci, Alessandra; Lai, Tiziana

    2008-04-01

    The heavy metal bioavailable fraction of a soil is a core parameter to verify the potential risks of contaminant exposure to organisms or plants. The purpose of the present work is to identify the bioavailable metal fraction in soils treated with chelates. This fraction was evaluated directly by analyzing metal concentrations in soil solution and indirectly using sequential extraction procedures. The metal bioavailable fraction was compared with metal accumulated in plant leaves, grown in both untreated and chelate-treated reactors. In order to verify the effect of the readily and slowly biodegradable chelates [S,S]-ethylenediaminedisuccinic acid (EDDS), methylglycine diacetic acid (MGDA), and ethylenediaminetetraacetic acid (EDTA) on metal speciation in soils, a simulation of chelate treatment was made and metal concentrations in different soil compartments before and after the simulation were compared. Lead concentration in the soil solution was positively correlated with metal concentration in the test plants. The soluble fraction showed the best correlation with metal concentration in soil solution. The simulation of the chelate treatment demonstrated that EDTA and EDDS were able to extract part of the organic- and sulfide-bound fraction, which are less available to plants. PMID:18253843

  20. Lentil (Lens culinaris L) as a candidate crop for iron biofortification: Is there a genetic potential for iron bioavailability?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Iron (Fe) deficiency is the most prevalent nutrient deficiency worldwide. Biofortification of staple food crops, such as the lentil (Lens culinaris L.), may be an effective solution. We analyzed the iron (Fe) concentration, Fe bioavailability, and phytic acid (PA) concentration of 23 lentil genotype...

  1. Hydroponic isotope labelling of entire plants (HILEP) for quantitative plant proteomics; an oxidative stress case study.

    PubMed

    Bindschedler, Laurence V; Palmblad, Magnus; Cramer, Rainer

    2008-07-01

    Hydroponic isotope labelling of entire plants (HILEP) is a cost-effective method enabling metabolic labelling of whole and mature plants with a stable isotope such as (15)N. By utilising hydroponic media that contain (15)N inorganic salts as the sole nitrogen source, near to 100% (15)N-labelling of proteins can be achieved. In this study, it is shown that HILEP, in combination with mass spectrometry, is suitable for relative protein quantitation of seven week-old Arabidopsis plants submitted to oxidative stress. Protein extracts from pooled (14)N- and (15)N-hydroponically grown plants were fractionated by SDS-PAGE, digested and analysed by liquid chromatography electrospray ionisation tandem mass spectrometry (LC-ESI-MS/MS). Proteins were identified and the spectra of (14)N/(15)N peptide pairs were extracted using their m/z chromatographic retention time, isotopic distributions, and the m/z difference between the (14)N and (15)N peptides. Relative amounts were calculated as the ratio of the sum of the peak areas of the two distinct (14)N and (15)N peptide isotope envelopes. Using Mascot and the open source trans-proteomic pipeline (TPP), the data processing was automated for global proteome quantitation down to the isoform level by extracting isoform specific peptides. With this combination of metabolic labelling and mass spectrometry it was possible to show differential protein expression in the apoplast of plants submitted to oxidative stress. Moreover, it was possible to discriminate between differentially expressed isoforms belonging to the same protein family, such as isoforms of xylanases and pathogen-related glucanases (PR 2). PMID:18538804

  2. Survival and Transfer of Murine Norovirus within a Hydroponic System during Kale and Mustard Microgreen Harvesting.

    PubMed

    Wang, Qing; Kniel, Kalmia E

    2016-01-01

    Hydroponically grown microgreens are gaining in popularity, but there is a lack of information pertaining to their microbiological safety. The potential risks associated with virus contamination of crops within a hydroponic system have not been studied to date. Here a human norovirus (huNoV) surrogate (murine norovirus [MNV]) was evaluated for its ability to become internalized from roots to edible tissues of microgreens. Subsequently, virus survival in recirculated water without adequate disinfection was assessed. Kale and mustard seeds were grown on hydroponic pads (for 7 days with harvest at days 8 to 12), edible tissues (10 g) were cut 1 cm above the pads, and corresponding pieces (4 cm by 4 cm) of pads containing only roots were collected separately. Samples were collected from a newly contaminated system (recirculated water inoculated with ∼3 log PFU/ml MNV on day 8) and from a previously contaminated system. (A contaminated system without adequate disinfection or further inoculation was used for production of another set of microgreens.) Viral titers and RNA copies were quantified by plaque assay and real-time reverse transcription (RT)-PCR. The behaviors of MNV in kale and mustard microgreens were similar (P > 0.05). MNV was detected in edible tissues and roots after 2 h postinoculation, and the levels were generally stable during the first 12 h. Relatively low levels (∼2.5 to ∼1.5 log PFU/sample of both edible tissues and roots) of infectious viruses were found with a decreasing trend over time from harvest days 8 to 12. However, the levels of viral RNA present were higher and consistently stable (∼4.0 to ∼5.5 log copies/sample). Recirculated water maintained relatively high levels of infectious MNV over the period of harvest, from 3.54 to 2.73 log PFU/ml. Importantly, cross-contamination occurred easily; MNV remained infectious in previously contaminated hydroponic systems for up to 12 days (2.26 to 1.00 PFU/ml), and MNV was detected in both

  3. Survival and Transfer of Murine Norovirus within a Hydroponic System during Kale and Mustard Microgreen Harvesting

    PubMed Central

    Wang, Qing

    2015-01-01

    Hydroponically grown microgreens are gaining in popularity, but there is a lack of information pertaining to their microbiological safety. The potential risks associated with virus contamination of crops within a hydroponic system have not been studied to date. Here a human norovirus (huNoV) surrogate (murine norovirus [MNV]) was evaluated for its ability to become internalized from roots to edible tissues of microgreens. Subsequently, virus survival in recirculated water without adequate disinfection was assessed. Kale and mustard seeds were grown on hydroponic pads (for 7 days with harvest at days 8 to 12), edible tissues (10 g) were cut 1 cm above the pads, and corresponding pieces (4 cm by 4 cm) of pads containing only roots were collected separately. Samples were collected from a newly contaminated system (recirculated water inoculated with ∼3 log PFU/ml MNV on day 8) and from a previously contaminated system. (A contaminated system without adequate disinfection or further inoculation was used for production of another set of microgreens.) Viral titers and RNA copies were quantified by plaque assay and real-time reverse transcription (RT)-PCR. The behaviors of MNV in kale and mustard microgreens were similar (P > 0.05). MNV was detected in edible tissues and roots after 2 h postinoculation, and the levels were generally stable during the first 12 h. Relatively low levels (∼2.5 to ∼1.5 log PFU/sample of both edible tissues and roots) of infectious viruses were found with a decreasing trend over time from harvest days 8 to 12. However, the levels of viral RNA present were higher and consistently stable (∼4.0 to ∼5.5 log copies/sample). Recirculated water maintained relatively high levels of infectious MNV over the period of harvest, from 3.54 to 2.73 log PFU/ml. Importantly, cross-contamination occurred easily; MNV remained infectious in previously contaminated hydroponic systems for up to 12 days (2.26 to 1.00 PFU/ml), and MNV was detected in both

  4. From Bioavailability Science to Regulation of Organic Chemicals.

    PubMed

    Ortega-Calvo, Jose-J; Harmsen, Joop; Parsons, John R; Semple, Kirk T; Aitken, Michael D; Ajao, Charmaine; Eadsforth, Charles; Galay-Burgos, Malyka; Naidu, Ravi; Oliver, Robin; Peijnenburg, Willie J G M; Römbke, Jörg; Streck, Georg; Versonnen, Bram

    2015-09-01

    The bioavailability of organic chemicals in soil and sediment is an important area of scientific investigation for environmental scientists, although this area of study remains only partially recognized by regulators and industries working in the environmental sector. Regulators have recently started to consider bioavailability within retrospective risk assessment frameworks for organic chemicals; by doing so, realistic decision-making with regard to polluted environments can be achieved, rather than relying on the traditional approach of using total-extractable concentrations. However, implementation remains difficult because scientific developments on bioavailability are not always translated into ready-to-use approaches for regulators. Similarly, bioavailability remains largely unexplored within prospective regulatory frameworks that address the approval and regulation of organic chemicals. This article discusses bioavailability concepts and methods, as well as possible pathways for the implementation of bioavailability into risk assessment and regulation; in addition, this article offers a simple, pragmatic and justifiable approach for use within retrospective and prospective risk assessment. PMID:26230485

  5. Understanding and managing oral bioavailability: physiological concepts and patents.

    PubMed

    Alam, Mohd A; Al-Jenoobi, Fahad I; Al-Mohizea, Abdullah M; Ali, Raisuddin

    2015-01-01

    Oral delivery of poorly bioavailable therapeuticals is challenging. The challenges are more serious when physiological factors of gut such as cytochrome P450, P-glycoprotein, permeability, pH triggered precipitation and degradation are responsible for poor bioavailability. P-Glycoprotein mediated multidrug resistance is on high agenda for anti-cancer drugs. The present article compiled different methodologies used to curb these challenges of bioavailability. The concepts of poor bioavailability are illustrated along with possible management. Numerous relevant patents for bioavailability enhancement are also highlighted. Though, there is no universal approach for bioavailability enhancement, the drug related challenges are managed by altering its physicochemical characteristics or employing formulation technology, while the effects of physiological factors are minimized by using efflux transport inhibitor or cytochrome P-450 inhibitor or prodrug or through formulation technologies (enteric coating or microenvironment of pH etc.). PMID:25230073

  6. Oral absorption and bioavailability of flumequine in veal calves.

    PubMed

    Mevius, D J; Breukink, H J; Jansen, T; Guelen, P J; de Grève, B

    1989-10-01

    The oral absorption and bioavailability of flumequine was studied in 1-, 5- and 18-week-old calves following intravenous and oral administration of different formulations of flumequine (Flumix, Flumix C and pure flumequine). Increasing age had a negative influence on the Cmax after the administration of Flumix, based on a larger VD in the older calves. The Cmax decreased from 5.02 +/- 1.46 micrograms/ml in the first week to 3.28 +/- 0.42 micrograms/ml in the 18th week. Adding colistin sulfate to the flumequine formulation and administring pure flumequine mixed with milk replacer had a negative effect on the Cmax of flumequine after oral administration of 5 and 10 mg/kg body weight. The bioavailability of the orally administered flumequine formulations was 100% in all cases except after the administration of Flumix C, for which it was 75.9 +/- 18.2%. The urinary recovery of flumequine after intravenous injection of a 10% solution varied from 35.2 +/- 2.3% for Group B, to 41.2 +/- 6.3% for Group C. The dosage of 5 mg/kg body weight Flumix twice daily in 1-week-old veal calves is sufficient to reach therapeutic plasma concentrations, based on a MIC value of 0.8 micrograms/ml of the target bacteria. In older calves it is advisable to increase the dosage 7.5 or 10 mg/kg body weight every 12 hours. In combination with colistin sulfate it is also advisable to increase the dosage slightly because of the negative effect of the colistin sulfate on the Cmax of flumequine. PMID:2603356

  7. Automated lettuce nutrient solution management using an array of ion-selective electrodes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Automated sensing and control of macronutrients in hydroponic solutions would allow more efficient management of nutrients for crop growth in closed systems. This paper describes the development and evaluation of a computer-controlled nutrient management system with an array of ion-selective electro...

  8. Stimulating in situ surfactant production to increase contaminant bioavailability and augment bioremediation of petroleum hydrocarbons

    NASA Astrophysics Data System (ADS)

    Haws, N. W.; Bentley, H. W.; Yiannakakis, A.; Bentley, A. J.; Cassidy, D. P.

    2006-12-01

    The effectiveness of a bioremediation strategy is largely dependent on relationships between contaminant sequestration (geochemical limitations) and microbial degradation potential (biological limitations). As contaminant bioavailability becomes mass transfer limited, contaminant removal will show less sensitivity to biodegradation enhancements without concurrent enhancements to rates of mass transfer into the bioavailable phase. Implementing a strategy that can simultaneously address geochemical and biological limitations is motivated by a subsurface zone of liquid petroleum hydrocarbons (LPH) contamination that is in excess of 10 acres (40,000 sq. meters). Biodegradation potential at the site is high; however, observed biodegradation rates are generally low, indicative of bioavailability limitations (e.g., low aqueous solubilities, nutrient deficiencies, and/or mass transfer limitations), and estimates indicate that bioremediation (i.e., biosparging/bioventing) with unaugmented biodegradation may be unable to achieve the remedial objectives within an acceptable time. Bench-scale experiments using soils native to the site provide evidence that, in addition to nutrient additions, a pulsed oxygen delivery can increase biodegradation rates by stimulating the microbial production of biosurfactants (rhamnolipids), leading to a reduction in surface tension and an increase in contaminant bioavailability. Pilot-scale tests at the field site are evaluating the effectiveness of stimulating in situ biosurfactant production using cyclic biosparging. The cyclic sparging creates extended periods of alternating aerobic and oxygen-depleted conditions in the submerged smear zone. The increased bioavailability of LPH and the resulting biodegradation enhancements during the test are evaluated using measurements of surface tension (as confirmation of biosurfactant accumulation) and nitrate concentrations (as substantiation of anaerobic biodegradation during shut-off periods). The

  9. Effects of arsenic species and concentrations on arsenic accumulation by different fern species in a hydroponic system.

    PubMed

    Fayiga, A O; Ma, L Q; Santos, Jorge; Rathinasabapathi, B; Stamps, B; Littell, R C

    2005-01-01

    Two hydroponic experiments were conducted to evaluate factors affecting plant arsenic (As) hyperaccumulation. In the first experiment; two As hyperaccumulators (Pteris vittata and P. cretica mayii) were exposed to 1 and 10 mg L(-1) arsenite (AsIII) and monomethyl arsenic acid (MMA) for 4 wk. Total As concentrations in plants (fronds and roots) and solution were determined In the second experiment P. vittata and Nephrolepis exaltata (a non-As hyperaccumulator) were exposed to 5 mgL(-1) arsenate (AsV) and 20 mgL(-1) AsIIIfor 1 and 15 d. Total As and AsIII concentrations in plants were determined Compared to P. cretica mayii, P. vittata was more efficient in arsenic accumulation (1075-1666 vs. 249-627mg kg(-1) As in the fronds) partially because it is more efficient in As translocation. As translocation factor (As concentration ratio in fronds to roots) was 3.0-5.6 for P. vittata compared to 0.1 to 4.8 for P. cretica. Compared to N. exaltata, P. vittata was significantly more efficient in arsenic accumulation (38-542 vs. 4.8-71 mg kg(-1) As in thefronds) as well asAs translocation (1.3-5.6 vs. 0.2-0.5). In addition, P. vittata was much more efficient in As reduction from AsV to AsIII (83-84 vs. 13-24% AsIII in the fronds). Little As reduction occurred after 1-d exposure to AsV in both species indicates that As reduction was not instantaneous even in an As hyperaccumulator. Our data were consistent with the hypothesis that both As translocation and As reduction are important for plant As hyperaccumulation. PMID:16285413

  10. Variations in metal tolerance and accumulation in three hydroponically cultivated varieties of Salix integra treated with lead.

    PubMed

    Wang, Shufeng; Shi, Xiang; Sun, Haijing; Chen, Yitai; Pan, Hongwei; Yang, Xiaoe; Rafiq, Tariq

    2014-01-01

    Willow species have been suggested for use in the remediation of contaminated soils due to their high biomass production, fast growth, and high accumulation of heavy metals. The tolerance and accumulation of metals may vary among willow species and varieties, and the assessment of this variability is vital for selecting willow species/varieties for phytoremediation applications. Here, we examined the variations in lead (Pb) tolerance and accumulation of three cultivated varieties of Salix integra (Weishanhu, Yizhibi and Dahongtou), a shrub willow native to northeastern China, using hydroponic culture in a greenhouse. In general, the tolerance and accumulation of Pb varied among the three willow varieties depending on the Pb concentration. All three varieties had a high tolerance index (TI) and EC50 value (the effective concentration of Pb in the nutrient solution that caused a 50% inhibition on biomass production), but a low translocation factor (TF), indicating that Pb sequestration is mainly restricted in the roots of S. integra. Among the three varieties, Dahogntou was more sensitive to the increased Pb concentration than the other two varieties, with the lowest EC50 and TI for root and above-ground tissues. In this respect, Weishanhu and Yizhibi were more suitable for phytostabilization of Pb-contaminated soils. However, our findings also indicated the importance of considering the toxicity symptoms when selecting willow varieties for the use of phytoremediation, since we also found that the three varieties revealed various toxicity symptoms of leaf wilting, chlorosis and inhibition of shoot and root growth under the higher Pb concentrations. Such symptoms could be considered as a supplementary index in screening tests. PMID:25268840

  11. Bioavailability of bioactive food compounds: a challenging journey to bioefficacy

    PubMed Central

    Rein, Maarit J.; Renouf, Mathieu; Cruz‐Hernandez, Cristina; Actis‐Goretta, Lucas; Thakkar, Sagar K.; da Silva Pinto, Marcia

    2013-01-01

    Bioavailability is a key step in ensuring bioefficacy of bioactive food compounds or oral drugs. Bioavailability is a complex process involving several different stages: liberation, absorption, distribution, metabolism and elimination phases (LADME). Bioactive food compounds, whether derived from various plant or animal sources, need to be bioavailable in order to exert any beneficial effects. Through a better understanding of the digestive fate of bioactive food compounds we can impact the promotion of health and improvement of performance. Many varying factors affect bioavailability, such as bioaccessibility, food matrix effect, transporters, molecular structures and metabolizing enzymes. Bioefficacy may be improved through enhanced bioavailability. Therefore, several technologies have been developed to improve the bioavailability of xenobiotics, including structural modifications, nanotechnology and colloidal systems. Due to the complex nature of food bioactive compounds and also to the different mechanisms of absorption of hydrophilic and lipophilic bioactive compounds, unravelling the bioavailability of food constituents is challenging. Among the food sources discussed during this review, coffee, tea, citrus fruit and fish oil were included as sources of food bioactive compounds (e.g. (poly)phenols and polyunsaturated fatty acids (PUFAs)) since they are examples of important ingredients for the food industry. Although there are many studies reporting on bioavailability and bioefficacy of these bioactive food components, understanding their interactions, metabolism and mechanism of action still requires extensive work. This review focuses on some of the major factors affecting the bioavailability of the aforementioned bioactive food compounds. PMID:22897361

  12. Bioavailability of Micronutrients from Plant Foods: An Update.

    PubMed

    Platel, Kalpana; Srinivasan, Krishnapura

    2016-07-26

    Deficiencies of iron, zinc, iodine and vitamin A are widespread in the developing countries, poor bioavailability of these micronutrients from plant-based foods being the major reason for their wide prevalence. Diets predominantly vegetarian are composed of components that enhance as well as inhibit mineral bioavailability, the latter being predominant. However, prudent cooking practices and use of ideal combinations of food components can significantly improve micronutrient bioavailability. Household processing such as heat treatment, sprouting, fermentation and malting have been evidenced to enhance the bioavailability of iron and β-carotene from plant foods. Food acidulants amchur and lime are also shown to enhance the bioavailability of not only iron and zinc, but also of β-carotene. Recently indentified newer enhancers of micronutrient bioaccessibility include sulphur compound-rich Allium spices-onion and garlic, which also possess antioxidant properties, β-carotene-rich vegetables-carrot and amaranth, and pungent spices-pepper (both red and black) as well as ginger. Information on the beneficial effect of these dietary compounds on micronutrient bioaccessibility is novel. These food components evidenced to improve the bioavailability of micronutrients are common ingredients of Indian culinary, and probably of other tropical countries. Fruits such as mango and papaya, when consumed in combination with milk, provide significantly higher amounts of bioavailable β-carotene. Awareness of the beneficial influence of these common dietary ingredients on the bioavailability of micronutrients would help in devising dietary strategies to improve the bioavailability of these vital nutrients. PMID:25748063

  13. The bioavailability of chemicals in soil for earthworms

    USGS Publications Warehouse

    Lanno, R.; Wells, J.; Conder, Jason M.; Bradham, K.; Basta, N.

    2004-01-01

    The bioavailability of chemicals to earthworms can be modified dramatically by soil physical/chemical characteristics, yet expressing exposure as total chemical concentrations does not address this problem. In order to understand the effects of modifying factors on bioavailability, one must measure and express chemical bioavailability to earthworms in a consistent, logical manner. This can be accomplished by direct biological measures of bioavailability (e.g., bioaccumulation, critical body residues), indirect biological measures of bioavailability (e.g., biomarkers, reproduction), or indirect chemical measures of bioavailability (e.g., chemical or solid-phase extracts of soil). If indirect chemical measures of bioavailability are to be used, they must be correlated with some biological response. Bioavailability can be incorporated into ecological risk assessment during risk analysis, primarily in the estimation of exposure. However, in order to be used in the site-specific ecological risk assessment of chemicals, effects concentrations must be developed from laboratory toxicity tests based on exposure estimates utilizing techniques that measure the bioavailable fraction of chemicals in soil, not total chemical concentrations. ?? 2003 Elsevier Inc. All rights reserved.

  14. Speciation Matters: Bioavailability of Silver and Silver Sulfide Nanoparticles to Alfalfa (Medicago sativa).

    PubMed

    Stegemeier, John P; Schwab, Fabienne; Colman, Benjamin P; Webb, Samuel M; Newville, Matthew; Lanzirotti, Antonio; Winkler, Christopher; Wiesner, Mark R; Lowry, Gregory V

    2015-07-21

    Terrestrial crops are directly exposed to silver nanoparticles (Ag-NPs) and their environmentally transformed analog silver sulfide nanoparticles (Ag2S-NPs) when wastewater treatment biosolids are applied as fertilizer to agricultural soils. This leads to a need to understand their bioavailability to plants. In the present study, the mechanisms of uptake and distribution of silver in alfalfa (Medicago sativa) were quantified and visualized upon hydroponic exposure to Ag-NPs, Ag2S-NPs, and AgNO3 at 3 mg total Ag/L. Total silver uptake was measured in dried roots and shoots, and the spatial distribution of elements was investigated using transmission electron microscopy (TEM) and synchrotron-based X-ray imaging techniques. Despite large differences in release of Ag(+) ions from the particles, Ag-NPs, Ag2S-NPs, and Ag(+) became associated with plant roots to a similar degree, and exhibited similarly limited (<1%) amounts of translocation of silver into the shoot system. X-ray fluorescence (XRF) mapping revealed differences in the distribution of Ag into roots for each treatment. Silver nanoparticles mainly accumulated in the (columella) border cells and elongation zone, whereas Ag(+) accumulated more uniformly throughout the root. In contrast, Ag2S-NPs remained largely adhered to the root exterior, and the presence of cytoplasmic nano-SixOy aggregates was observed. Exclusively in roots exposed to particulate silver, NPs smaller than the originally dosed NPs were identified by TEM in the cell walls. The apparent accumulation of Ag in the root apoplast determined by XRF, and the presence of small NPs in root cell walls suggests uptake of partially dissolved NPs and translocation along the apoplast. PMID:26106801

  15. A reexamination of krill oil bioavailability studies.

    PubMed

    Salem, Norman; Kuratko, Connye N

    2014-01-01

    It has proven difficult to compare the bioavailability of krill oil (KO) vs. fish oil (FO) due to several of the characteristics of KO. These include the lower concentration of the active ingredients, eicosapentaenoic acid (EPA, 20:5n-3) and docosahexaenoic acid (DHA, 22:6n3), in KO as well as differences in their ratio relative to FO as well as the red color due to astaxanthin. In addition, the lipid classes in which EPA and DHA are found are quite different with KO containing phospholipid, di- and tri-glycerides as well as non-esterified fatty acid forms and with FO being primarily triglycerides. No human study has yet been performed that matches the dose of EPA and DHA in a randomized, controlled trial with measures of bloodstream EPA and DHA content. However, several claims have been made suggesting greater bioavailability of KO vs. FO. These have largely been based on a statistical argument where a somewhat lower dose of KO has been used to result in a similar bloodstream level of EPA and/or DHA or their total. However, the magnitude of the dosage differential is shown to be too small to be expected to result in differing blood levels of the long chain n-3 PUFAs. Some studies which have claimed to provide equal doses of KO and FO have actually used differing amounts of the two major n-3 fatty acid constituents. It is concluded that there is at present no evidence for greater bioavailability of KO vs. FO and that more carefully controlled human trials must be performed to establish their relative efficacies after chronic administration. PMID:25156381

  16. Isoflavones: estrogenic activity, biological effect and bioavailability.

    PubMed

    Vitale, Daniela Cristina; Piazza, Cateno; Melilli, Barbara; Drago, Filippo; Salomone, Salvatore

    2013-03-01

    Isoflavones are phytoestrogens with potent estrogenic activity; genistein, daidzein and glycitein are the most active isoflavones found in soy beans. Phytoestrogens have similarity in structure with the human female hormone 17-β-estradiol, which can bind to both alpha and beta estrogen receptors, and mimic the action of estrogens on target organs, thereby exerting many health benefits when used in some hormone-dependent diseases. Numerous clinical studies claim benefits of genistein and daidzein in chemoprevention of breast and prostate cancer, cardiovascular disease and osteoporosis as well as in relieving postmenopausal symptoms. The ability of isoflavones to prevent cancer and other chronic diseases largely depends on pharmacokinetic properties of these compounds, in particular absorption and distribution to the target tissue. The chemical form in which isoflavones occur is important because it influences their bioavailability and, therefore, their biological activity. Glucose-conjugated isoflavones are highly polar, water-soluble compounds. They are hardly absorbed by the intestinal epithelium and have weaker biological activities than the corresponding aglycone. Different microbial families of colon can transform glycosylated isoflavones into aglycones. Clinical studies show important differences between the aglycone and conjugated forms of genistein and daidzein. The evaluation of isoflavone metabolism and bioavailability is crucial to understanding their biological effects. Lipid-based formulations such as drug incorporation into oils, emulsions and self-microemulsifying formulations have been introduced to increase bioavailability. Complexation with cyclodextrin also represent a valid method to improve the physicochemical characteristics of these substances in order to be absorbed and distributed to target tissues. We review and discuss pharmacokinetic issues that critically influence the biological activity of isoflavones. PMID:23161396

  17. Bioavailability of heavy metals in strongly acidic soils treated with exceptional quality biosolids

    SciTech Connect

    Basta, N.T.; Sloan, J.J.

    1999-03-01

    New federal regulations may increase application of exceptional quality (EQ) biosolids to acidic soils, and information on the effect of this practice on bioavailability of heavy metal is limited. The objective of this study was to compare bioavailability of heavy metal in soil treated with nonalkaline or alkaline EQ biosolids with limestone-treated soils. Three acidic soils (pH 3.7--4.3) were treated with three amounts of lime-stabilized biosolids (LS), anaerobic-digested biosolids (AN), or agricultural limestone (L), and incubated at 25 C. Soil solution Cd, Zn, and other chemical constituents were measured at 1, 30, 90, and 180 d incubation. Soil solution Cd and Zn were AN > LS {ge} L, C. Soil solution Cd and Zn increased with AN applied but decreased wit h LS applied. The high application of LS had soil solution Zn dramatically decreased at soil pH > 5.5 and >5.1, respectively. Soil solution Cd and Zn increases were AN > LS with incubation time. Biosolids treatments increased heavy metal in Ca(NO{sub 3}){sub 2} and NaOAc fractions. Except for Cd, most metal from biosolids were in EDTA and HNO{sub 3} fractions. Heavy metal bioavailability, measured using lettuce (Latuca sativa L.), was AN > LS {ge} L, C. Although state regulations prohibiting application of nonalkaline EQ biosolids to acidic soil is a prudent practice, application of EQ alkaline biosolids that achieves soil pH > 5 minimizes risk from soil solution Cd and Zn and plant uptake of heavy metal.

  18. Uptake of cadmium by hydroponically grown, mature Eucalyptus camaldulensis saplings and the effect of organic ligands.

    PubMed

    Fine, P; Rathod, Paresh H; Beriozkin, A; Mingelgrin, U

    2013-01-01

    The potential suitability of Eucalyptus camaldulensis for Cd phytoextraction was tested in a hydroponic study. Saplings were exposed to 4.5 and 89 microM Cd for one month, with and without EDTA and s,s-EDDS at 0.1, 1, and 5 mM. The saplings' growth was not affected at the 4.5 microM Cd concentration, yet it decreased 3-fold at 89 microM, and almost all the Cd taken up was immobilized in the roots, reaching 360 and 5300 mg Cd kg(-1), respectively (approximately 75% of which was non-washable in acid). The respective Cd root-to-shoot translocation factors were 0.14 and approximately 5*10(-4). At 0.1 mM concentration, EDTA and EDDS had no effect or even a positive effect on the saplings growth. This was reversed at 1 mM, and the chelants became lethal at the 5 mM concentration. At 89 microM Cd in the growth medium, 0.1 mM EDTA increased Cd translocation into the shoots by almost 10-fold, however it strongly reduced Cd content inside the roots. This hydroponic study indicates the feasibility of E. camaldulensis use for cleanup Cd-contaminated soils at environmental concentrations, both for site stabilization (phytostabilization) and gradual remediation (phytoextraction). EDTA was shown to be much more efficient in enhancing Cd translocation than s,s-EDDS. PMID:23819299

  19. Removal of nitrate and phosphorus from hydroponic wastewater using a hybrid denitrification filter (HDF).

    PubMed

    Park, J B K; Craggs, R J; Sukias, J P S

    2009-07-01

    A laboratory-scale hybrid-denitrification filter (HDF) was designed by combining a plant material digester and a denitrification filter into a single unit for the removal of nitrate and phosphorus from glasshouse hydroponic wastewater. The carbon to nitrate (C:N) ratio for efficient operation of the HDF was calculated to be 1.93:1 and the COD/BOD(5) ratio was 1.2:1. When the HDF was continuously operated with the plant material replaced every 2 days and 100% internal recirculation of the effluent, a high level of nitrate removal (320-5 mg N/L, >95% removal) combined with a low effluent sBOD(5) concentration (<5mg/L) was consistently achieved. Moreover, phosphate concentrations in the effluent were maintained below 7.5 mg P/L (>81% reduction). This study demonstrates the potential to combine a digester and a denitrification filter in a single unit to efficiently remove nitrate and phosphate from hydroponic wastewater in a single unit. PMID:19303287

  20. Treatment of hydroponic wastewater by denitrification filters using plant prunings as the organic carbon source.

    PubMed

    Park, J B K; Craggs, R J; Sukias, J P S

    2008-05-01

    This study investigated the feasibility of using pre-treated plant liquors as organic carbon sources for the treatment of hydroponic wastewater containing high nitrate-N (>300 mg N/L). The waste plant material was pre-treated to extract organic carbon-rich liquors. When this plant liquor was used as an organic carbon source in denitrification filters at the organic carbon:nitrogen dose rate of 3C:N, nitrate removal efficiencies were >95% and final effluent nitrate concentrations were consistently <20mg N/L. However, at this dose rate, relatively high concentrations (>140 mg/L) of organic carbon (fBOD5) remained in the final effluents. Therefore, a 'compromise' organic carbon:nitrogen dose rate (2C:N) was trialled, at which nitrate removal efficiencies were maintained at >85%, final effluent nitrate concentrations were consistently below 45 mg N/L, and effluent fBOD5 concentrations were <25mg/L. This study has demonstrated that waste plant material is a suitable carbon source for the removal of nitrate from hydroponic wastewater in a denitrification filter. PMID:17714940

  1. Survival of Potentially Pathogenic Human-Associated Bacteria in the Rhizosphere of Hydroponically Grown Wheat

    NASA Technical Reports Server (NTRS)

    Morales, Anabelle; Garland, Jay L.; Lim, Daniel V.

    1996-01-01

    Plants may serve as reservoirs for human-associated bacteria (H-AB) in long-term space missions containing bioregenerative life support systems. The current study examined the abilities of five human-associated potential pathogens, Pseudomonas aeruginosa, Pseudomonas cepacia, Staphylococcus aureus, Streptococcus pyogenes, and Escherichia coli, to colonize and grow in the rhizosphere of hydroponically grown wheat, a candidate crop for life support. All of these bacteria have been recovered from past NASA missions and present potential problems for future missions. The abilities of these organisms to adhere to the roots of axenic five-day-old wheat (Triticum aestivum L. cv. Yecora rojo) were evaluated by enumeration of the attached organisms after a one hour incubation of roots in a suspension (approximately 10(exp 8 cu/ml)) of the H-AB. Results showed that a greater percentage of P. aeruginosa cells adhered to the wheat roots than the other four H-AB. Similarly incubated seedlings were also grown under attempted axenic conditions for seven days to examine the potential of each organism to proliferate in the rhizosphere (root colonization capacity). P. cepacia and P. aeruginosa showed considerable growth. E. coli and S. aureus showed no significant growth, and S. pyogenes died off in the wheat rhizosphere. Studies examining the effects of competition on the survival of these microorganisms indicated that P. aeruginosa was the only organism that survived in the rhizosphere of hydroponically grown wheat in the presence of different levels of microbial competition.

  2. Survival of potentially pathogenic human-associated bacteria in the rhizosphere of hydroponically grown wheat.

    PubMed

    Morales, A; Garland, J L; Lim, D V

    1996-07-01

    Plants may serve as reservoirs for human-associated bacteria (H-AB) in long-term space missions containing bioregenerative life support systems. The current study examined the abilities of five human-associated potential pathogens, Pseudomonas aeruginosa, Pseudomonas cepacia, Staphylococcus aureus, Streptococcus pyogenes and Escherichia coli, to colonize and grow in the rhizosphere of hydroponically grown wheat, a candidate crop for life support. All of these bacteria have been recovered from past NASA missions and present potential problems for future missions. The abilities of these organisms to adhere to the roots of axenic five-day-old wheat (Triticum aestivum L. cv. Yecora rojo) were evaluated by enumeration of the attached organisms after a one hour incubation of roots in a suspension (approximately 10(8) cfu ml-1) of the H-AB. Results showed that a greater percentage of P. aeruginosa cells adhered to the wheat roots than the other four H-AB. Similarly incubated seedlings were also grown under attempted axenic conditions for seven days to examine the potential of each organism to proliferate in the rhizosphere (root colonization capacity). P. cepacia and P. aerogiunosa showed considerable growth, E. coli and S. aureus showed no significant growth, and S. pyogenes died off in the wheat rhizosphere. Studies examining the effects of competition on the survival of these microorganisms indicated that P. aeruginosa was the only organism that survived in the rhizosphere of hydroponically grown wheat in the presence of different levels of microbial competition. PMID:11539850

  3. Coupling bioaccumulation and phytotoxicity to predict copper removal by switchgrass grown hydroponically.

    PubMed

    Juang, Kai-Wei; Lai, Hung-Yu; Chen, Bo-Ching

    2011-06-01

    A major challenge in phytoextraction is to increase plants' removal rates of metals from contaminated soils. In this study, we developed a phytoextraction model, by coupling a saturable Michaelis-Menten type accumulation model and an energy-based toxicity model, to predict copper (Cu) removal by switchgrass (Panicum virgatum L.) grown hydroponically under various exposure concentrations. Results of the present study indicated that the phytotoxicity of Cu to switchgrass is relatively low, whereas a certain accumulation capacity exists in the plant for Cu. In addition, the simulation results suggested that, under a lower dissolved concentration, Cu removal is increased more efficiently as the exposure duration increases. Although it is difficult to extrapolate the results from greenhouse-based hydroponic experiments to field conditions, we believe that the current methodology can offer a first approximation in predicting the phytoextraction duration needed for plant species to remove a specific metal from contaminated sites, which is crucial in evaluating the economic costs for remediation purposes. PMID:21409589

  4. Garlic exerts allelopathic effects on pepper physiology in a hydroponic co-culture system.

    PubMed

    Ding, Haiyan; Cheng, Zhihui; Liu, Menglong; Hayat, Sikandar; Feng, Han

    2016-01-01

    A hydroponic co-culture system was adopted to determine the allelopathic potential of garlic on the growth of pepper plants. Different numbers of garlic plants (0, 2, 4, 8 and 12) were hydroponically co-cultured with two pepper plants to investigate allelopathic effects on the growth attributes and antioxidative defense system of the test pepper plants. The responses of the pepper plants depended on the number of garlic plants included in the co-culture system, indicating an association of pepper growth with the garlic root exudate concentration. When grown at a pepper/garlic ratio of 1:1 or 1:2, the pepper plant height, chlorophyll content, and peroxidase (POD), catalase (CAT) and phenylalanine ammonia-lyase (PAL) activities were significantly increased after 30 days of co-culture; in contrast, reduction in methane dicarboxylic aldehyde (MDA) content was observed. However, when the pepper/garlic ratio was 1:4 or higher, these morphological indices and protective enzyme activities were significantly inhibited, whereas MDA levels in the pepper leaves were significantly increased due to severe membrane lipid peroxidation. The results indicate that although low concentrations of garlic root exudates appear to induce protective enzyme systems and promote pepper growth, high concentrations have deleterious effects. These findings suggest that further investigations should optimize the co-culture pepper/garlic ratio to reduce continuous cropping obstacles in pepper production. PMID:27095440

  5. Garlic exerts allelopathic effects on pepper physiology in a hydroponic co-culture system

    PubMed Central

    Ding, Haiyan; Liu, Menglong; Hayat, Sikandar; Feng, Han

    2016-01-01

    ABSTRACT A hydroponic co-culture system was adopted to determine the allelopathic potential of garlic on the growth of pepper plants. Different numbers of garlic plants (0, 2, 4, 8 and 12) were hydroponically co-cultured with two pepper plants to investigate allelopathic effects on the growth attributes and antioxidative defense system of the test pepper plants. The responses of the pepper plants depended on the number of garlic plants included in the co-culture system, indicating an association of pepper growth with the garlic root exudate concentration. When grown at a pepper/garlic ratio of 1:1 or 1:2, the pepper plant height, chlorophyll content, and peroxidase (POD), catalase (CAT) and phenylalanine ammonia-lyase (PAL) activities were significantly increased after 30 days of co-culture; in contrast, reduction in methane dicarboxylic aldehyde (MDA) content was observed. However, when the pepper/garlic ratio was 1:4 or higher, these morphological indices and protective enzyme activities were significantly inhibited, whereas MDA levels in the pepper leaves were significantly increased due to severe membrane lipid peroxidation. The results indicate that although low concentrations of garlic root exudates appear to induce protective enzyme systems and promote pepper growth, high concentrations have deleterious effects. These findings suggest that further investigations should optimize the co-culture pepper/garlic ratio to reduce continuous cropping obstacles in pepper production. PMID:27095440

  6. Enhanced cutaneous bioavailability of dehydroepiandrosterone mediated by nano-encapsulation.

    PubMed

    Badihi, Amit; Debotton, Nir; Frušić-Zlotkin, Marina; Soroka, Yoram; Neuman, Rami; Benita, Simon

    2014-09-10

    Polymeric nanocarriers, especially nanospheres (NSs) and nanocapsules (NCs), can promote the penetration of their cargo through the skin barrier, towards improved cutaneous bioavailability. Dehydroepiandrosterone (DHEA), an endogenous hormone exhibiting poor aqueous solubility, was shown to be effective in modulating skin-aging processes following topical application. In this study, we designed adequate DHEA preparations, in an attempt to enable local delivery of the active ingredient to the viable skin layers. In addition, the potential efficiency of DHEA NCs on dermal collagen synthesis was evaluated. Cryo-TEM observations and thermal analysis indicated that DHEA was successfully incorporated within a stable NC-based delivery system. Moreover, higher [(3)H]-DHEA levels were recorded in the viable skin layers following different incubation periods of NCs on excised pig skin specimens as compared to DHEA oil solution (free molecule). Furthermore, significantly higher (4-fold) skin flux values were observed for the DHEA NCs as compared to the values elicited by the oil control solution. Finally, collagen synthesis in human skin organ culture, assessed by the incorporation of [(3)H]-proline, was up to 42% higher for DHEA NCs 48h post-topical application than for the untreated specimens. Overall, these results suggest that poly lactic-co-glycolic acid (PLGA)-based NCs have promising potential to be used topically for various skin disorders. PMID:24956487

  7. Planar Microdevices for Enhanced In Vivo Retention and Oral Bioavailability of Poorly Permeable Drugs

    PubMed Central

    Chirra, Hariharasudhan D.; Shao, Ling; Ciaccio, Natalie; Fox, Cade B.; Wade, Jennifer M.; Ma, Averil

    2014-01-01

    The development of novel oral drug delivery platforms for administering therapeutics in a safe and effective manner through the harsh gastrointestinal environment is of great importance. Here, the use of engineered thin planar poly(methyl methacrylate) (PMMA) microdevices is tested to enhance oral bioavailability of acyclovir, a poorly permeable drug. Acyclovir is loaded into the unidirectional drug releasing microdevice reservoirs using a drug entrapping photocross-linkable hydrogel matrix. An increase in acyclovir permeation across in vitro caco-2 monolayer is seen in the presence of microdevices as compared with acyclovir-entrapped hydrogels or free acyclovir solution. Cell proliferation studies show that microdevices are relatively nontoxic in nature for use in in vivo studies. Enhanced in vivo retention of microdevices is observed as their thin side walls experience minimal peristaltic shear stress as compared with spherical microparticles. Unidirectional acyclovir release and enhanced retention of microdevices achieve a 4.5-fold increase in bioavailability in vivo as compared with an oral gavage of acyclovir solution with the same drug mass. The enhanced oral bioavailability results suggest that thin, planar, bioadhesive, and unidirectional drug releasing microdevices will significantly improve the systemic and localized delivery of a broad range of oral therapeutics in the near future. PMID:24711341

  8. Bioavailability of the Nano-Unit 14C-Agrochemicals Under Various Water Potential.

    PubMed

    Jung, S C; Kim, H G; Kuk, Y I; Ahn, H G; Senseman, S A; Lee, D J

    2015-08-01

    The study was conducted to investigate the effects of water potential on bioavailability of the nano-unit 14C-cafenstrole, 14C-pretilachlor, 14C-benfuresate, 14C-simetryn and 14C-oxyfluorfen applied with or without dimepiperate or daimuron under various water potential conditions. The highest bioavailable concentration in soil solution (BCSS) was found at 60% soil moisture, while the lowest occurred at 50% soil moisture for soil-applied alone or in combination. All water potential conditions differed significantly from each other with variations in total bioavailable amount in soil solution (TBSS) when either dimepiperate or daimuron were added to the soil, and changes were directly proportional to variations in water potential. Across all treatments, TBSS at 80% soil moisture was three to four times greater than that at 50% soil moisture when applied alone or in combination with dimepiperate or daimuron. Cafenstrole and simetryn had distribution coefficient (Kd) values <64 ml g-1 and a TBSS ranging from 10 to 44 ng g-1 soil, regardless of water potential conditions applied alone or in combination. Pretilachlor and benfuresate had Kd values <15 ml g-1 and a TBSS range of 38 to 255 ng g-1 soil when applied with or without dimepiperate or daimuron. PMID:26369226

  9. A comparison of hydroponic and soil-based screening methods to identify salt tolerance in the field in barley.

    PubMed

    Tavakkoli, Ehsan; Fatehi, Foad; Rengasamy, Pichu; McDonald, Glenn K

    2012-06-01

    Success in breeding crops for yield and other quantitative traits depends on the use of methods to evaluate genotypes accurately under field conditions. Although many screening criteria have been suggested to distinguish between genotypes for their salt tolerance under controlled environmental conditions, there is a need to test these criteria in the field. In this study, the salt tolerance, ion concentrations, and accumulation of compatible solutes of genotypes of barley with a range of putative salt tolerance were investigated using three growing conditions (hydroponics, soil in pots, and natural saline field). Initially, 60 genotypes of barley were screened for their salt tolerance and uptake of Na(+), Cl(-), and K(+) at 150 mM NaCl and, based on this, a subset of 15 genotypes was selected for testing in pots and in the field. Expression of salt tolerance in saline solution culture was not a reliable indicator of the differences in salt tolerance between barley plants that were evident in saline soil-based comparisons. Significant correlations were observed in the rankings of genotypes on the basis of their grain yield production at a moderately saline field site and their relative shoot growth in pots at EC(e) 7.2 [Spearman's rank correlation (rs)=0.79] and EC(e) 15.3 (rs=0.82) and the crucial parameter of leaf Na(+) (rs=0.72) and Cl(-) (rs=0.82) concentrations at EC(e) 7.2 dS m(-1). This work has established screening procedures that correlated well with grain yield at sites with moderate levels of soil salinity. This study also showed that both salt exclusion and osmotic tolerance are involved in salt tolerance and that the relative importance of these traits may differ with the severity of the salt stress. In soil, ion exclusion tended to be more important at low to moderate levels of stress but osmotic stress became more important at higher stress levels. Salt exclusion coupled with a synthesis of organic solutes were shown to be important components of

  10. A comparison of hydroponic and soil-based screening methods to identify salt tolerance in the field in barley

    PubMed Central

    Tavakkoli, Ehsan; Fatehi, Foad; Rengasamy, Pichu; McDonald, Glenn K.

    2012-01-01

    Success in breeding crops for yield and other quantitative traits depends on the use of methods to evaluate genotypes accurately under field conditions. Although many screening criteria have been suggested to distinguish between genotypes for their salt tolerance under controlled environmental conditions, there is a need to test these criteria in the field. In this study, the salt tolerance, ion concentrations, and accumulation of compatible solutes of genotypes of barley with a range of putative salt tolerance were investigated using three growing conditions (hydroponics, soil in pots, and natural saline field). Initially, 60 genotypes of barley were screened for their salt tolerance and uptake of Na+, Cl–, and K+ at 150 mM NaCl and, based on this, a subset of 15 genotypes was selected for testing in pots and in the field. Expression of salt tolerance in saline solution culture was not a reliable indicator of the differences in salt tolerance between barley plants that were evident in saline soil-based comparisons. Significant correlations were observed in the rankings of genotypes on the basis of their grain yield production at a moderately saline field site and their relative shoot growth in pots at ECe 7.2 [Spearman’s rank correlation (rs)=0.79] and ECe 15.3 (rs=0.82) and the crucial parameter of leaf Na+ (rs=0.72) and Cl– (rs=0.82) concentrations at ECe 7.2 dS m−1. This work has established screening procedures that correlated well with grain yield at sites with moderate levels of soil salinity. This study also showed that both salt exclusion and osmotic tolerance are involved in salt tolerance and that the relative importance of these traits may differ with the severity of the salt stress. In soil, ion exclusion tended to be more important at low to moderate levels of stress but osmotic stress became more important at higher stress levels. Salt exclusion coupled with a synthesis of organic solutes were shown to be important components of salt

  11. Fluoride bioavailability in saliva and plaque

    PubMed Central

    2012-01-01

    Background Different fluoride formulations may have different effects on caries prevention. It was the aim of this clinical study to assess the fluoride content, provided by NaF compared to amine fluoride, in saliva and plaque. Methods Eight trained volunteers brushed their teeth in the morning for 3 minutes with either NaF or amine fluoride, and saliva and 3-day-plaque-regrowth was collected at 5 time intervals during 6 hours after tooth brushing. The amount of collected saliva and plaque was measured, and the fluoride content was analysed using a fluoride sensitive electrode. All subjects repeated all study cycles 5 times, and 3 cycles per subject underwent statistical analysis using the Wilcoxon-Mann-Whitney test. Results Immediately after brushing the fluoride concentration in saliva increased rapidly and dropped to the baseline level after 360 minutes. No difference was found between NaF and amine fluoride. All plaque fluoride levels were elevated after 30 minutes until 120 minutes after tooth brushing, and decreasing after 360 minutes to baseline. According to the highly individual profile of fluoride in saliva and plaque, both levels of bioavailability correlated for the first 30 minutes, and the fluoride content of saliva and plaque was back to baseline after 6 hours. Conclusions Fluoride levels in saliva and plaque are interindividually highly variable. However, no significant difference in bioavailability between NaF and amine fluoride, in saliva, or in plaque was found. PMID:22230722

  12. Prodrugs of perzinfotel with improved oral bioavailability.

    PubMed

    Baudy, Reinhardt B; Butera, John A; Abou-Gharbia, Magid A; Chen, Hong; Harrison, Boyd; Jain, Uday; Magolda, Ronald; Sze, Jean Y; Brandt, Michael R; Cummons, Terri A; Kowal, Diane; Pangalos, Menelas N; Zupan, Bojana; Hoffmann, Matthew; May, Michael; Mugford, Cheryl; Kennedy, Jeffrey; Childers, Wayne E

    2009-02-12

    Previous studies with perzinfotel (1), a potent, selective, competitive NMDA receptor antagonist, showed it to be efficacious in inflammatory and neuropathic pain models. To increase the low oral bioavailability of 1 (3-5%), prodrug derivatives (3a-h) were synthesized and evaluated. The oxymethylene-spaced diphenyl analogue 3a demonstrated good stability at acidic and neutral pH, as well as in simulated gastric fluid. In rat plasma, 3a was rapidly converted to 1 via 2a. Pharmacokinetic studies indicated that the amount of systemic exposure of 1 produced by a 10 mg/kg oral dose of 3a was 2.5-fold greater than that produced by a 30 mg/kg oral dose of 1. Consistent with these results, 3a was significantly more potent and had a longer duration of activity than 1 following oral administration in a rodent model of inflammatory pain. Taken together, these results demonstrate that an oxymethylene-spaced prodrug approach increased the bioavailability of 1. PMID:19146418

  13. Supplementing iron bioavailability enhanced mung bean.

    PubMed

    Purushothaman, Vijayalakshmi; M, Amirthaveni; Tsou, Samson C S; S, Shanmugasundaram

    2008-01-01

    Iron deficiency anaemia is a major public health problem. The high incidence is either due to insufficient intake of iron or poor bio availability. Enhancing the bio availability is as important as increasing the intake. The absorption could be enhanced by including ascorbic acid and beta carotene containing fruits and vegetables into recipes of iron containing food preparations. The effect of supplementation of iron bio-availability enhanced mung bean preparations was studied on 75 women who were compared against 75 who served as controls and another 75 who consumed regular traditional recipes. The methodology included identification of suitable mung bean variety, assessing iron in vitro bio availability, mapping the anaemic women, estimating their iron levels, supplementation for one year and studying the effect of supplementation. Mung bean supplementation had increased serum protein levels from 5.36 to 6.73 g/dl, serum iron levels had increased from 16.6 to 46.7 microg/dl. The TIBC levels decreased from 555 to 508 microg/dl while serum ferritin levels increased from 3.56 to 5.94 microg/dl and Hb levels from 7.54 to 8.29 g/dl. Thus, improving the bioavailability of iron of food preparations, will improve the iron status of women. PMID:18296312

  14. Modulation of nitric oxide bioavailability by erythrocytes

    NASA Astrophysics Data System (ADS)

    Huang, Kuang-Tse; Han, Tae H.; Hyduke, Daniel R.; Vaughn, Mark W.; van Herle, Helga; Hein, Travis W.; Zhang, Cuihua; Kuo, Lih; Liao, James C.

    2001-09-01

    Nitric oxide (NO) activates soluble guanylyl cyclase in smooth muscle cells to induce vasodilation in the vasculature. However, as hemoglobin (Hb) is an effective scavenger of NO and is present in high concentrations inside the red blood cell (RBC), the bioavailability of NO would be too low to elicit soluble guanylyl cyclase activation in the presence of blood. Therefore, NO bioactivity must be preserved. Here we present evidence suggesting that the RBC participates in the preservation of NO bioactivity by reducing NO influx. The NO uptake by RBCs was increased and decreased by altering the degree of band 3 binding to the cytoskeleton. Methemoglobin and denatured hemoglobin binding to the RBC membrane or cytoskeleton also were shown to contribute to reducing the NO uptake rate of the RBC. These alterations in NO uptake by the RBC, hence the NO bioavailability, were determined to correlate with the vasodilation of isolated blood vessels. Our observations suggest that RBC membrane and cytoskeleton associated NO-inert proteins provide a barrier for NO diffusion and thus account for the reduction in the NO uptake rate of RBCs.

  15. Vitamin B12 sources and bioavailability.

    PubMed

    Watanabe, Fumio

    2007-11-01

    The usual dietary sources of vitamin B(12) are animal foods, meat, milk, egg, fish, and shellfish. As the intrinsic factor-mediated intestinal absorption system is estimated to be saturated at about 1.5-2.0 microg per meal under physiologic conditions, vitamin B(12) bioavailability significantly decreases with increasing intake of vitamin B(12) per meal. The bioavailability of vitamin B(12) in healthy humans from fish meat, sheep meat, and chicken meat averaged 42%, 56%-89%, and 61%-66%, respectively. Vitamin B(12) in eggs seems to be poorly absorbed (< 9%) relative to other animal food products. In the Dietary Reference Intakes in the United States and Japan, it is assumed that 50% of dietary vitamin B(12) is absorbed by healthy adults with normal gastro-intestinal function. Some plant foods, dried green and purple lavers (nori) contain substantial amounts of vitamin B(12), although other edible algae contained none or only traces of vitamin B(12). Most of the edible blue-green algae (cyanobacteria) used for human supplements predominantly contain pseudovitamin B(12), which is inactive in humans. The edible cyanobacteria are not suitable for use as vitamin B(12) sources, especially in vegans. Fortified breakfast cereals are a particularly valuable source of vitamin B(12) for vegans and elderly people. Production of some vitamin B(12)-enriched vegetables is also being devised. PMID:17959839

  16. Effect of some detergents, humate, and composition of seedbed on crop of tomato plants in a hydroponic culture

    NASA Technical Reports Server (NTRS)

    Guminka, A. Z.; Gracz-Nalepka, M.; Lukasiewicz, B.; Sobolewicz, E.; Turkiewicz, I. T.

    1978-01-01

    It is established that single detergent doses distinctly stimulate vegetative development of plants in the initial stage when humates are available. When detergents are applied every four weeks in a hydroponic culture, in which the seedbed does not contain active humates, the crop is reduced by 50%. This adverse effect does not occur when the seedbed is a mixture of brown coal and peat.

  17. Estimating Lead (Pb) Bioavailability In A Mouse Model

    EPA Science Inventory

    Children are exposed to Pb through ingestion of Pb-contaminated soil. Soil Pb bioavailability is estimated using animal models or with chemically defined in vitro assays that measure bioaccessibility. However, bioavailability estimates in a large animal model (e.g., swine) can be...

  18. Bioaccessibility tests accurately estimate bioavailability of lead to quail

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Hazards of soil-borne Pb to wild birds may be more accurately quantified if the bioavailability of that Pb is known. To better understand the bioavailability of Pb, we incorporated Pb-contaminated soils or Pb acetate into diets for Japanese quail (Coturnix japonica), fed the quail for 15 days, and ...

  19. ASSESSING SOIL ARSENIC BIOAVAILABILITY IN THE LABORATORY MOUSE

    EPA Science Inventory

    Variation among soils in the bioavailability of arsenic can be a critical determinant of the risk posed by exposure to these soils. Although in vitro techniques can provide vital data on aspects of bioavailability of metals and metalloids from soils, these results must be valida...

  20. BIOACCESSIBILITY TESTS ACCURATELY ESTIMATE BIOAVAILABILITY OF LEAD TO QUAIL

    EPA Science Inventory

    Hazards of soil-borne Pb to wild birds may be more accurately quantified if the bioavailability of that Pb is known. To better understand the bioavailability of Pb to birds, we measured blood Pb concentrations in Japanese quail (Coturnix japonica) fed diets containing Pb-contami...

  1. DISTRIBUTION OF PARAMETERS DETERMINING BIOAVAILABILITY OF METALS IN EUROPEAN SOILS

    EPA Science Inventory

    As part of a program to develop a predictive model of bioavailability and toxicity of copper in soils to terrestrial organisms, 19 soils from 9 countries of the EU were collected and analyzed for use in bioavailability tests. However, it is desired that the model be of use on a ...

  2. The bioavailability of iron fortified in whole grain parboiled rice

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The present study was to evaluate the bioavailability of iron (Fe) fortified in parboiled rice grain, expressed as Fe uptake by Caco-2 cells after in vitro digestion. The bioavailability of Fe-fortified in the rice grain was closely and positively correlated with increasing concentrations of Fe in t...

  3. Bioavailability and Uptake of Lead by Coffeeweed (Sesbania exaltata Raf.)

    PubMed Central

    Miller, Gloria; Begonia, Gregorio; Begonia, Maria; Ntoni, Jennifer

    2008-01-01

    Lead (Pb) is recognized as one of the most pervasive environmental health concerns in the industrialized world. While there has been a substantial reduction in the use of Pb in gasoline, water pipes, and Pb-based residential paint, residual Pb from their use is still in the environment and constitutes an important source of Pb in the atmosphere, water, and soil. Soil acts as a sink for these anthropogenic sources of Pb, accumulating the deposits over time in the upper 2 – 5 cm of undisturbed soil. Generally, Pb binds strongly to soil particles and renders a significant soil-metal fraction insoluble and largely unavailable for phytoremediation or plant uptake. A major objective of current phytoremediation research, therefore, is to induce desorption of Pb from the soil matrix into solution and increase the propensity for plant uptake. We hypothesized that the bioavailability of Pb for plant uptake can be increased through chelate amendments. To test this hypothesis, we mixed delta top soil and peat (2:1) and added lead nitrate [Pb (NO3)2] to generate a Pb-contaminated soil concentration of 2000 mg Pb/kg dry soil. After incubating the Pb-spiked soil in a greenhouse for 6 weeks, Sesbania plants were grown in the soil and harvested at 6, 8, and 10 weeks after emergence. Six days before each harvest, a chelating agent, ethylenediaminetetraacetic acid (EDTA) was applied to the root zone as an aqueous solution in a 1:1 ratio with the Pb concentration in the soil. Sequential extraction procedures were used to assess selective chemical fractions of Pb in the soil. Our results showed that a higher exchangeable fraction of Pb was available for plant uptake after chelate amendment compared to pre-chelate amendment. We also saw higher root and shoot Pb uptake after chelate amendment compared to pre-chelate amendment, especially at 10 weeks after emergence. Together, these results suggest that chelate amendments can promote the bioavailability of Pb in the soil and increased

  4. Mineralogy affects geoavailability, bioaccessibility and bioavailability of zinc

    PubMed Central

    Molina, Ramon M.; Schaider, Laurel A.; Donaghey, Thomas C.; Shine, James P.; Brain, Joseph D.

    2013-01-01

    We correlated mineralogical and particle characteristics of Zn-containing particles with Zn geoavailability, bioaccessibility, and bioavailability following gavage and intranasal (IN) administration in rats. We compared samples of Zn/Pb mine waste and five pulverized pure-phase Zn minerals (<38 μm). Particles were neutron-activated to produce radioactive 65Zn. We assessed geoavailability using sequential extractions and bioaccessibility using in vitro extraction tests simulating various pH and biological conditions. Zn in vivo bioavailability and in vitro bioaccessibility decreased as follows: mine waste > hydrozincite > hemimorphite > zincite ≈ smithsonite ≫ sphalerite. We found significant correlations among geoavailability, bioaccessibility and bioavailability. In particular, Zn bioavailability post-gavage and post-IN was significantly correlated with bioaccessibility in simulated phagolysosomal fluid and gastric fluid. These data indicate that solid phase speciation influences biological uptake of Zn and that in vitro tests can be used to predict Zn bioavailability in exposure assessment and effective remediation design. PMID:23933126

  5. Hemicellulose does not affect iron bioavailability in chicks.

    PubMed

    Fly, A D; Czarnecki-Maulden, G L; Fahey, G C; Titgemeyer, E C

    1996-01-01

    Two iron repletion experiments using hemoglobin as a response criterion were conducted to assess effects of hemicelluloses on iron bioavailability to chicks. In Experiment 1, iron bioavailability from intact fiber sources was determined by adding tomato pomace (14.6% hemicelluloses), soybean hulls (20.6% hemicelluloses), beet pulp (21.5% hemicelluloses), orchard grass (24.1% hemicelluloses) and corn fiber (55.2% hemicelluloses) to a casein dextrose basal diet providing 0.4-4.1% hemicelluloses to the diet. Test foods were analyzed for iron, total dietary fiber, neutral detergent residue, neutral detergent fiber, acid detergent fiber, acid detergent lignin, pectins and uronic acids. Hemicelluloses were determined by the difference of neutral detergent residue minus acid detergent fiber. Iron bioavailability was determined by the standard curve method to be (percent relative to ferrous sulfate using hemoglobin as the response criterion) as follows: tomato pomace, 82.0; soybean hulls, 94.0; beet pulp, 26.5; orchard grass, 68.9; corn fiber, 69.4. Iron bioavailability was not related to hemicellulose content of test foods or diets. In Experiment 2, the effect of psyllium husk (a fiber source that contains predominantly hemicelluloses) on iron bioavailability from ferrous sulfate was assessed. Bioavailability was determined by the slope ratio method where treatments consisted of graded levels of ferrous sulfate in the presence and absence of 5% dietary psyllium. Although iron intrinsic to psyllium was unavailable, bioavailability of ferrous sulfate iron was not affected (P > 0.05) by the presence of psyllium. Thus, there was no clear effect of hemicelluloses on iron bioavailability. However, some feeds that contained high levels of hemicelluloses had low intrinsic iron bioavailabilities, suggesting that other dietary factors are primarily responsible for determining iron bioavailability from these feed components. PMID:8558316

  6. Selection and hydroponic growth of bread wheat cultivars for bioregenerative life support systems

    NASA Astrophysics Data System (ADS)

    Page, V.; Feller, U.

    2013-08-01

    As part of the ESA-funded MELiSSA program, the suitability, the growth and the development of four bread wheat cultivars were investigated in hydroponic culture with the aim to incorporate such a cultivation system in an Environmental Control and Life Support System (ECLSS). Wheat plants can fulfill three major functions in space: (a) fixation of CO2 and production of O2, (b) production of grains for human nutrition and (c) production of cleaned water after condensation of the water vapor released from the plants by transpiration. Four spring wheat cultivars (Aletsch, Fiorina, Greina and CH Rubli) were grown hydroponically and compared with respect to growth and grain maturation properties. The height of the plants, the culture duration from germination to harvest, the quantity of water used, the number of fertile and non-fertile tillers as well as the quantity and quality of the grains harvested were considered. Mature grains could be harvested after around 160 days depending on the varieties. It became evident that the nutrient supply is crucial in this context and strongly affects leaf senescence and grain maturation. After a first experiment, the culture conditions were improved for the second experiment (stepwise decrease of EC after flowering, pH adjusted twice a week, less plants per m2) leading to a more favorable harvest (higher grain yield and harvest index). Considerably less green tillers without mature grains were present at harvest time in experiment 2 than in experiment 1. The harvest index for dry matter (including roots) ranged from 0.13 to 0.35 in experiment 1 and from 0.23 to 0.41 in experiment 2 with modified culture conditions. The thousand-grain weight for the four varieties ranged from 30.4 to 36.7 g in experiment 1 and from 33.2 to 39.1 g in experiment 2, while market samples were in the range of 39.4-46.9 g. Calcium levels in grains of the hydroponically grown wheat were similar to those from field-grown wheat, while potassium, magnesium

  7. Microbiological profile and incidence of Salmonella and Listeria monocytogenes on hydroponic bell peppers and greenhouse cultivation environment.

    PubMed

    Avila-Vega, Dulce E; Alvarez-Mayorga, Beatriz; Arvizu-Medrano, Sofía M; Pacheco-Aguilar, Ramiro; Martínez-Peniche, Ramón; Hernández-Iturriaga, Montserrat

    2014-11-01

    The aim of this study was to generate information regarding the microbiological profile, including Salmonella and Listeria monocytogenes incidence, of hydroponically grown bell peppers and materials associated with their production in greenhouses located in Mexico. Samples of coconut fiber (24), knives (30), drippers (20), conveyor belts (161), pepper transportation wagons (30), air (178), water (16), nutrient solution for plant irrigation (78), and bell pepper fruits (528) were collected during one cycle of production (2009 to 2010) for the quantification of microbial indicators (aerobic plate counts [APC], molds, coliforms, and Escherichia coli) and the detection of Salmonella and L. monocytogenes. With regard to surfaces (conveyor belts and wagons) and utensils (knives and drippers), the APC, coliform, and mold counts ranged from 3.0 to 6.0, from 1.4 to 6.3, and from 3.6 to 5.2 log CFU/100 cm(2) or per utensil, respectively. The air in the greenhouse contained low median levels of APC (1.2 to 1.4 log CFU/100 liters) and molds (2.2 to 2.5 log CFU/100 liters). The median content of APC and coliforms in water were 0.5 log CFU/ml and 0.3 log MPN/100 ml, respectively. The median content of coliforms in nutrient solution ranged from 1.8 to 2.4 log MPN/100 ml, and E. coli was detected in 18 samples (range, <0.3 to 1.2 log MPN/100 ml). On bell pepper analyzed during the study, populations (median) of APC, coliforms, and molds were 5.4, 3.6, and 5.8 log CFU per fruit, respectively; E. coli was detected in 5.1% of the samples (range, 0.23 to 1.4 log MPN per fruit). Salmonella was isolated from only one sample (1.6%) of conveyor belt located at the packing area and in four bell pepper samples (3%). L. monocytogenes was not detected. This information could help producers to establish effective control measures to prevent the presence of foodborne pathogens in bell peppers based on a scientific approach. PMID:25364924

  8. Orally Bioavailable Potent Soluble Epoxide Hydrolase Inhibitors

    PubMed Central

    Hwang, Sung Hee; Tsai, Hsing-Ju; Liu, Jun-Yan; Morisseau, Christophe; Hammock, Bruce D.

    2008-01-01

    A series of N,N′-disubstituted ureas having a conformationally restricted cis- or trans-1,4-cyclohexane α to the urea were prepared and tested as soluble epoxide hydrolase (sEH) inhibitors. This series of compounds showed low nanomolar to picomolar activities against recombinant human sEH. Both isomers showed similar potencies, but the trans isomers were more metabolically stable in human hepatic microsomes. Furthermore, these new potent inhibitors show a greater metabolic stability in vivo than previously described sEH inhibitors. We demonstrated that trans-4-[4-(3-adamantan-1-ylureido)cyclohexyloxy]benzoic acid 13g (t-AUCB, IC50 = 1.3 ± 0.05 nM) had excellent oral bioavailability (98%, n = 2) and blood area under the curve in dogs and was effective in vivo to treat hypotension in lipopolysaccharide challenged murine models. PMID:17616115

  9. Bioavailability of vitamin A sources for cattle.

    PubMed

    Alosilla, C E; McDowell, L R; Wilkinson, N S; Staples, C R; Thatcher, W W; Martin, F G; Blair, M

    2007-05-01

    An experiment was conducted to evaluate the bioavailability of 5 sources of vitamin A. It was hypothesized that some vitamin A products have protective coatings that are more resistant than others to rumen destruction and that such protection would result in greater tissue concentrations of vitamin A. Fifty-three yearling Angus x Brahman cattle, consisting of 39 steers and 14 heifers, were stratified by BW and sex and randomly assigned to 6 high-concentrate diet groups receiving no vitamin A supplementation (control) or vitamin A supplemented from the following sources: Microvit A (Adisseo, Acworth, GA), Rovamix A (DSM, Parsippany, NJ), Sunvit A, Lutavit A, and Microvit A DLC (Adisseo). The vitamin A treatment groups were fed daily 80,000 IU of retinol/animal in a low-retinol concentrate diet (78.5% oats, 10% cottonseed hulls, 8% molasses, and 2% cottonseed meal; DM basis) and a free-choice, poor quality (low carotene) hay for 84 d. Every 28 d, BW was determined and liver biopsies and plasma were collected and analyzed for retinol concentrations. All retinol treatments showed significant increases in liver retinol concentrations compared with control animals (P < 0.0001), which steadily decreased over time. At all collection times, Microvit A led to numerically, but not significantly, greater concentrations of retinol in liver than did all other treatments. However, at the end of the experiment, there was no significant difference in liver retinol concentration among Microvit A, Rovamix A, Lutavit A, and Microvit A DLC diets. When liver retinol concentrations at all collection times were considered, Microvit A and Rovamix A appeared to provide the most bioavailable vitamin A. PMID:17178810

  10. Tissue culture system using a PANDA ring resonator and wavelength router for hydroponic plant.

    PubMed

    Kamoldilok, Surachart; Suwanpayak, Nathaporn; Suttirak, Saisudawan; Yupapin, Preecha P

    2012-06-01

    A novel system of nanofluidics trapping and delivery, which is known as a tissue culture system is proposed. By using the intense optical pulse(i.e., a soliton pulse) and a system constructed by a liquid core waveguide, the optical vortices (gradient optical fields/wells) can be generated, where the trapping tools in the same way as the optical tweezers in the PANDA ring resonator can be formed. By controlling the suitable parameters, the intense optical vortices can be generated within the PANDA ring resonator, in which the nanofluidics can be trapped and moved (transported) dynamically within the Tissue culture system(a wavelength router), which can be used for tissue culture and delivery in the hydroponic plant system. PMID:22411055

  11. The dynamics of hydroponic crops for simulation studies of the CELSS initial reference configurations

    NASA Technical Reports Server (NTRS)

    Volk, Tyler

    1992-01-01

    The goal of this research is to develop a progressive series of mathematical models for the CELSS hydroponic crops. These models will systematize the experimental findings from the crop researchers in the CELSS Program into a form useful to investigate system-level considerations, for example, dynamic studies of the CELSS Initial Reference Configurations. The crop models will organize data from different crops into a common modeling framework. This is the fifth semiannual report for this project. The following topics are discussed: (1) use of field crop models to explore phasic control of CELSS crops for optimizing yield; (2) seminar presented at Purdue CELSS NSCORT; and (3) paper submitted on analysis of bioprocessing of inedible plant materials.

  12. Using hydroponic biomass to regulate NOx emissions in long range space travel

    SciTech Connect

    Xu, X.H.; Shi, Y.; Chang, S.G.; Fisher, J.; Pisharody, S.; Moran, M.; Wignarajah, K.

    2002-02-01

    The incineration of wastes is one of the most promising reclamation technologies being developed for life support in long range space travel. However, incineration in a closed environment will build up hazardous NOx if not regulated. A technology that can remove NOx under microgravity conditions without the need of expendables is required. Activated carbon prepared from inedible wheat straw and sweet potato stalk that were grown under hydroponic conditions has been demonstrated to be able to adsorb NO and reduce it to N{sub 2}. The high mineral content in the activated carbon prepared from hydroponic biomass prohibits high surface area production and results in inferior NO adsorption capacity. The removal of mineral from the carbon circumvents the aforementioned negative effect. The optimal production conditions to obtain maximum yield and surface area for the activated carbon have been determined. A parametric study on the NO removal efficiency by the activated carbon has been done. The presence of oxygen in flue gas is essential for effective adsorption of NO by the activated carbon. On the contrary, water vapor inhibits the adsorption efficiency of NO. The NO adsorption capacity and the duration before it exceeds the Space Maximum Allowable Concentration were determined. After the adsorption of NO, the activated carbon can be regenerated for reuse by heating the carbon bed under anaerobic conditions to above 500 C, when the adsorbed NO is reduced to N{sub 2}. The regenerated activated carbon exhibits improved NO adsorption efficiency. However, regeneration had burned off a small percentage of the activated carbon.

  13. Salmonella internalization in mung bean sprouts and pre- and postharvest intervention methods in a hydroponic system.

    PubMed

    Ge, Chongtao; Rymut, Susan; Lee, Cheonghoon; Lee, Jiyoung

    2014-05-01

    Mung bean sprouts, typically consumed raw or minimally cooked, are often contaminated with pathogens. Internalized pathogens pose a high risk because conventional sanitization methods are ineffective for their inactivation. The studies were performed (i) to understand the potential of internalization of Salmonella in mung bean sprouts under conditions where the irrigation water was contaminated and (ii) to determine if pre- and postharvest intervention methods are effective in inactivating the internalized pathogen. Mung bean sprouts were grown hydroponically and exposed to green fluorescence protein-tagged Salmonella Typhimurium through maturity. One experimental set received contaminated water daily, while other sets received contaminated water on a single day at different times. For preharvest intervention, irrigation water was exposed to UV, and for postharvest intervention-contaminated sprouts were subjected to a chlorine wash and UV light. Harvested samples were disinfected with ethanol and AgNO3 to differentiate surface-associate pathogens from the internalized ones. The internalized Salmonella Typhimurium in each set was quantified using the plate count method. Internalized Salmonella Typhimurium was detected at levels of 2.0 to 5.1 log CFU/g under all conditions. Continuous exposure to contaminated water during the entire period generated significantly higher levels of Salmonella Typhimurium internalization than sets receiving contaminated water for only a single day (P < 0.05). Preintervention methods lowered the level of internalized Salmonella by 1.84 log CFU/g (P < 0.05), whereas postintervention methods were ineffective in eliminating internalized pathogens. Preintervention did not completely inactivate bacteria in sprouts and demonstrated that the remaining Salmonella Typhimurium in water became more resistant to UV. Because postharvest intervention methods are ineffective, proper procedures for maintaining clean irrigation water must be followed

  14. Detection of bioavailable cadmium, lead, and arsenic in polluted soil by tailored multiple Escherichia coli whole-cell sensor set.

    PubMed

    Hou, Qihui; Ma, Anzhou; Wang, Thanh; Lin, Jianqiang; Wang, Hailin; Du, Binghai; Zhuang, Xuliang; Zhuang, Guoqiang

    2015-09-01

    Microbial whole-cell sensor has been widely used to assess bioavailability and risk of toxic elements, but their environmental use is still limited due to the presence of other interfering pollutants and the nonspecific binding in cells, which leads to inaccurate results. Here, we proposed a strategy combining Escherichia coli sensor set with binary regression models for the specific detection of bioavailable cadmium (Cd), lead (Pb), and arsenic (As) in a co-polluted environment. Initial tests suggested that the sensor set respectively termed pcadCluc, pzntRluc, and parsRluc could be classified into two groups according to their specific response to Cd, Pb, and As: group 1 (pcadCluc and pzntRluc) induced by a Cd-Pb mix and group 2 (parsRluc) induced by a Cd-As mix. Based on the variance in responses of each sensor to mixtures of target elements, three binary linear equations for two sensor groups were set up to calculate the individual concentrations in the mixture solutions. This method was then used to quantify the bioavailable Cd, Pb, and As in soils from a co-polluted mining region and to compare the results with other methods. Results showed that the conventional single target sensor method overestimated the bioavailability of each element, while sensor set was credible for accurate bioavailable Cd, Pb, and As quantification and comparable with the results from inductively coupled plasma mass spectrometry (ICP-MS) analysis. Our method can potentially be extended to cover the specific detection of other bioavailable toxic elements in different environmental settings. PMID:26138890

  15. Evolutionary computational methods to predict oral bioavailability QSPRs.

    PubMed

    Bains, William; Gilbert, Richard; Sviridenko, Lilya; Gascon, Jose-Miguel; Scoffin, Robert; Birchall, Kris; Harvey, Inman; Caldwell, John

    2002-01-01

    This review discusses evolutionary and adaptive methods for predicting oral bioavailability (OB) from chemical structure. Genetic Programming (GP), a specific form of evolutionary computing, is compared with some other advanced computational methods for OB prediction. The results show that classifying drugs into 'high' and 'low' OB classes on the basis of their structure alone is solvable, and initial models are already producing output that would be useful for pharmaceutical research. The results also suggest that quantitative prediction of OB will be tractable. Critical aspects of the solution will involve the use of techniques that can: (i) handle problems with a very large number of variables (high dimensionality); (ii) cope with 'noisy' data; and (iii) implement binary choices to sub-classify molecules with behavior that are qualitatively different. Detailed quantitative predictions will emerge from more refined models that are hybrids derived from mechanistic models of the biology of oral absorption and the power of advanced computing techniques to predict the behavior of the components of those models in silico. PMID:11865672

  16. Self-microemulsifying drug delivery system for improved oral bioavailability of oleanolic acid: design and evaluation

    PubMed Central

    Yang, Rui; Huang, Xin; Dou, Jinfeng; Zhai, Guangxi; Su, Lequn

    2013-01-01

    Oleanolic acid is a poorly water-soluble drug with low oral bioavailability. A self-microemulsifying drug delivery system (SMEDDS) has been developed to enhance the solubility and oral bioavailability of oleanolic acid. The formulation design was optimized by solubility assay, compatibility tests, and pseudoternary phase diagrams. The morphology, droplet size distribution, zeta potential, viscosity, electrical conductivity, and refractive index of a SMEDDS loaded with oleanolic acid were studied in detail. Compared with oleanolic acid solution, the in vitro release of oleanolic acid from SMEDDS showed that the drug could be released in a sustained manner. A highly selective and sensitive high-performance liquid chromatographymass spectrometry method was developed for determination of oleanolic acid in rat plasma. This method was used for a pharmacokinetic study of an oleanolic acid-loaded SMEDDS compared with the conventional tablet in rats. Promisingly, a 5.07-fold increase in oral bioavailability of oleanolic acid was achieved for the SMEDDS compared with the marketed product in tablet form. Our studies illustrate the potential use of a SMEDDS for delivery of oleanolic acid via the oral route. PMID:23966781

  17. Preparation and enhancement of oral bioavailability of curcumin using microemulsions vehicle.

    PubMed

    Hu, Liandong; Jia, Yanhong; Niu, Feng; Jia, Zheng; Yang, Xun; Jiao, Kuiliang

    2012-07-25

    A new microemulsions system of curcumin (CUR-MEs) was successfully developed to improve the solubility and bioavailability of curcumin. Several formulations of the microemulsions system were prepared and evaluated using different ratios of oils, surfactants, and co-surfactants (S&CoS). The optimal formulation, which consists of Capryol 90 (oil), Cremophor RH40 (surfactant), and Transcutol P aqueous solution (co-surfactant), could enhance the solubility of curcumin up to 32.5 mg/mL. The pharmacokinetic study of microemulsions was performed in rats compared to the corresponding suspension. The stability of microemulsions after dilution was excellence. Microemulsions have significantly increased the C(max) and area under the curve (AUC) in comparison to that in suspension (p < 0.05). The relative bioavailability of curcumin in microemulsions was 22.6-fold higher than that in suspension. The results indicated that the CUR-MEs could be used as an effective formulation for enhancing the oral bioavailability of curcumin. PMID:22587560

  18. Effect of activated carbon on microbial bioavailability of phenanthrene in soils

    SciTech Connect

    Yang, Y.; Hunter, W.; Tao, S.; Crowley, D.; Gan, J.

    2009-11-15

    Bioavailability is a governing factor that controls the rate of biological degradation of hydrophobic organic contaminants in soil. Among the solid phases that can adsorb hydrophobic organic contaminants in soil, black carbon (BC) exerts a particularly significant effect on phase distribution. However, knowledge on the effect of BC on the microbial availability of polycyclic aromatic hydrocarbons in soil is still limited. In the present study, the effect of a coal-derived activated carbon on the bioavailability of phenanthrene (PHE) during its degradation by Mycobacterium vanbaalenii PYR-1 was measured in three soils. The freely dissolved concentration of PHE was concurrently determined in soil solutions using disposable polydimethylsiloxane fibers. The results showed that PHE mineralization was significantly inhibited after addition of activated carbon in all test soils. After 216 h, only 5.20, 5.83, and 6.85% of PHE was degraded in the 0.5% BC-amended soils initially containing organic carbon at 0.23, 2.1, and 7.1%, respectively. Significant correlation was found between PHE degradability and freely dissolved concentration, suggesting that BC affected PHE bioavailability by decreasing chemical activity. The effect of activated carbon in the amended soils was attributed to its enhancement of soil surface areas and pore volumes. Results from the present study clearly highlighted the importance of BC for influencing the microbial availability of polycyclic aromatic hydrocarbons in soils.

  19. Bioavailability an in vitro solubility of iron in green leafy vegetables

    SciTech Connect

    Miller, J.

    1986-03-05

    Bioavailability, measured by hemoglobin repletion in anemic rats, of iron in turnip greens, spinach, and broccoli was compared with its solubility in water, in 0.1 and 1.0 N HCl, and in 0.1 M acetic, citric and tartaric acids. Both in vivo and in vitro tests were conducted with raw plant materials and with vegetables that had been heat processed. Turnip greens were canned and spinach and broccoli were cooked in boiling water. Bioavailability of iron in turnip greens was significantly increased by heat processing and the RBV of canned greens was 70-90% of the standard FeSO/sub 4/. The RBV of spinach was about 50% and that of broccoli was about 80%, and the bioavailability of iron in neither of these vegetables was altered significantly by cooking. In vitro solubility of iron of raw turnip greens in water, the organic acids, and 0.1 N HCl was poor and was increased by heat treatment. Iron of raw spinach was somewhat more soluble in these media than that of raw turnip greens, but cooking had the effect of decreasing the proportion of iron on spinach that could be solubilized by the aqueous solutions. Thus, the in vitro solubility of iron in the green leafy vegetables was predictive of biological availability of this iron the anemic rats.

  20. Montelukast-loaded nanostructured lipid carriers: part I oral bioavailability improvement.

    PubMed

    Patil-Gadhe, Arpana; Pokharkar, Varsha

    2014-09-01

    The purpose of the study was to formulate montelukast-loaded nanostructured lipid carrier (MNLC) to improve its systemic bioavailability, avoid hepatic metabolism and reduce hepatic cellular toxicity due to metabolites. MNLC was prepared using melt-emulsification-homogenization method. Preformulation study was carried out to evaluate drug-excipient compatibility. MNLCs were prepared using spatially different solid and liquid lipid triglycerides. CAE (DL-Pyrrolidonecarboxylic acid salt of L-cocyl arginine ethyl ester), a cationic, biodegradable, biocompatible surfactant was used to stabilize the system. MNLCs were characterized by FTIR, XRPD and DSC to evaluate physicochemical properties. MNLCs having a particle size of 181.4 ± 6.5 nm with encapsulation efficiency of 96.13 ± 0.98% were prepared. FTIR findings demonstrated no interaction between the drug and excipients of the formulation which could lead to asymmetric vibrations. DSC and XRPD study confirmed stable amorphous form of the montelukast in lipid matrix. In vitro release study revealed sustained release over a period of 24 h. In vivo single dose oral pharmacokinetic study demonstrated 143-fold improvement in bioavailability as compared to montelukast-aqueous solution. Thus, the result of this study implies that developed MNLC formulation be suitable to sustain the drug release with improvement in the bioavailability. PMID:24878424

  1. Bioavailability of zinc, copper, and manganese from infant diets

    SciTech Connect

    Bell, J.G.

    1987-01-01

    A series of trace element absorption experiments were performed using the Sprague-Dawley suckling rat put and infant rhesis monkey (Macaca mulatta) with extrinsic radiolabeling to assess the bioavailability of Zn, Cu, and Mn from infant diets and to examine specific factors that affect absorption of these essential nutrients. Bioavailability of Cu as assessed by 6 h liver uptake (% of /sup 64/Cu dose) was highest from human milk and cow milk based formula and significantly lower from cow milk and soy based formula. Copper bioavailability from infant cereal products as assessed by whole body uptake (% of /sup 64/Cu dose) in d 20 rats, 9 h postintubation, was low compared to the bioavailability from cow milk or human milk alone. /sup 65/Zn uptake in d 20 rats, 9 h postintubation, was significantly lower from cereals fed alone or in combination with cow or human milk as compared to the uptake from the milks fed alone. Zn bioavailability varied among cereal diets, (lowest from cereals containing phytate and highest from cereal/fruit products). Mn bioavailability from infant diets was assessed using a modified suckling rat pup model. Bioavailability (24 h whole body retention of /sup 54/Mn) was high from all milks and commercial formulas tested.

  2. Preclinical pharmacokinetic evaluation of resveratrol trimethyl ether in sprague-dawley rats: the impacts of aqueous solubility, dose escalation, food and repeated dosing on oral bioavailability.

    PubMed

    Lin, Hai-Shu; Ho, Paul C

    2011-10-01

    Resveratrol trimethyl ether (trans-3,5,4'-trimethoxystilbene, RTE) is a naturally occurring and pharmacologically active resveratrol derivative. To evaluate its suitability as a drug candidate, a pharmacokinetic study was carried out in Sprague-Dawley rats with the emphasis to identify the impact of aqueous solubility, dose escalation, food, and repeated dosing on its oral bioavailability. Upon single intravenous administration (5 mg/kg), RTE displayed moderate clearance (35.5 ± 5.3 mL/min/kg) and a fairly long terminal elimination half-life (511 ± 136 min); dose escalation (5-20 mg/kg) did not cause nonlinear pharmacokinetics. When given orally in suspension (60 mg/kg), RTE was poorly absorbed with negligible bioavailability (< 1.5%), fasting further decreased its bioavailability (<1%). However, when administered in a solution formulated with randomly methylated-β-cyclodextrin (15 mg/kg), RTE was rapidly absorbed with good bioavailability (46.5 ± 4.8%). Dose escalation resulted in increased bioavailability (64.6 ± 8.0%) at the dose of 60 mg/kg. Repeated RTE dosing (7 daily oral doses) did not alter the clearance, terminal elimination half-life and bioavailability. In summary, the aqueous solubility of RTE was a barrier to oral absorption; repeated RTE administrations did not alter its pharmacokinetic profiles; as RTE possessed appropriate pharmacokinetic profiles, further investigation on RTE as a drug candidate is warranted. PMID:21520090

  3. A study on As, Cu, Pb and Zn (bio)availability in an abandoned mine area (São Domingos, Portugal) using chemical and ecotoxicological tools.

    PubMed

    Alvarenga, Paula; Laneiro, Cátia; Palma, Patrícia; de Varennes, Amarilis; Cunha-Queda, Cristina

    2013-09-01

    The aim of this study was to relate the results obtained by chemical methods, used to assess environmental (bio)availability, with the ecotoxic response and bioaccumulation of trace elements (TE) by the earthworm Eisenia fetida exposed to field-contaminated, metal-polluted soils from a sulphide mine. The extracting solution 0.5 M NH4CH3COO, 0.5 M CH3COOH and 0.02 M EDTA (pH 4.7), was able to predict environmental bioavailability of TE to E. fetida. However, the toxicological bioavailability could not be predicted from the results of the chemical extractions or from the bioaccumulation results: E. fetida reproduction was higher in soils where environmental bioavailability of TE and bioaccumulation values were also higher. In this study, the toxic response of the organism seemed to be more influenced by the overall nutritional status of the soil (e.g. pH, organic matter, plant nutrient availability and cation exchange capacity) than by its TE contamination. In the case of anthropogenic multi-contaminated sites, the different soil characteristics exert an important and confounding influence in the toxic response and the relationship between different bioavailable fractions cannot be easily established, emphasising the need to combine results from chemical methods with those from bioassays when evaluating the bioavailability of TE in these soils. PMID:23608975

  4. BIOAVAILABILITY, ENVIRONMENTAL TRANSFORMATION, AND DETOXIFICATION OF CORE/SHELL NANOMATERIALS

    EPA Science Inventory

    The proposed research is targeted at minimizing environmental and health risks associated with commercial nanotubes and quantum dots by proper management of core chemical toxicants. The work will lead to validated chemical screening assays for bioavailability assessment, data ...

  5. Synthesis of a stable and orally bioavailable englerin analogue.

    PubMed

    Fash, David M; Peer, Cody J; Li, Zhenwu; Talisman, Ian J; Hayavi, Sima; Sulzmaier, Florian J; Ramos, Joe W; Sourbier, Carole; Neckers, Leonard; Figg, W Douglas; Beutler, John A; Chain, William J

    2016-06-01

    Synthesis of analogues of englerin A with a reduced propensity for hydrolysis of the glycolate moiety led to a compound which possessed the renal cancer cell selectivity of the parent and was orally bioavailable in mice. PMID:27107948

  6. Bioaccessibility tests accurately estimate bioavailability of lead to quail

    USGS Publications Warehouse

    Beyer, W. Nelson; Basta, Nicholas T; Chaney, Rufus L.; Henry, Paula F.; Mosby, David; Rattner, Barnett A.; Scheckel, Kirk G.; Sprague, Dan; Weber, John

    2016-01-01

    Hazards of soil-borne Pb to wild birds may be more accurately quantified if the bioavailability of that Pb is known. To better understand the bioavailability of Pb to birds, we measured blood Pb concentrations in Japanese quail (Coturnix japonica) fed diets containing Pb-contaminated soils. Relative bioavailabilities were expressed by comparison with blood Pb concentrations in quail fed a Pb acetate reference diet. Diets containing soil from five Pb-contaminated Superfund sites had relative bioavailabilities from 33%-63%, with a mean of about 50%. Treatment of two of the soils with phosphorus significantly reduced the bioavailability of Pb. Bioaccessibility of Pb in the test soils was then measured in six in vitro tests and regressed on bioavailability. They were: the “Relative Bioavailability Leaching Procedure” (RBALP) at pH 1.5, the same test conducted at pH 2.5, the “Ohio State University In vitro Gastrointestinal” method (OSU IVG), the “Urban Soil Bioaccessible Lead Test”, the modified “Physiologically Based Extraction Test” and the “Waterfowl Physiologically Based Extraction Test.” All regressions had positive slopes. Based on criteria of slope and coefficient of determination, the RBALP pH 2.5 and OSU IVG tests performed very well. Speciation by X-ray absorption spectroscopy demonstrated that, on average, most of the Pb in the sampled soils was sorbed to minerals (30%), bound to organic matter (24%), or present as Pb sulfate (18%). Additional Pb was associated with P (chloropyromorphite, hydroxypyromorphite and tertiary Pb phosphate), and with Pb carbonates, leadhillite (a lead sulfate carbonate hydroxide), and Pb sulfide. The formation of chloropyromorphite reduced the bioavailability of Pb and the amendment of Pb-contaminated soils with P may be a thermodynamically favored means to sequester Pb.

  7. Effect of EDTA on Pb(II) Uptake and Translocation by Tumbleweed (Salsola Kali): Agar and Hydroponics Studies

    SciTech Connect

    de la Rosa, Guadalupe; Gardea-Torresdey, Jorge L.; Peralta-Videa, Jose R.; Aldrich, Mary

    2004-03-31

    Environmental accumulation of Pb represents a worldwide health hazard. While conventional cleanup techniques are generally expensive and soil disturbing, phytoremediation represents an inexpensive friendly option for the removal of contaminants from soil and water. In this research, tumbleweed (Salsola kali) plants exposed for 15 days to Pb(NO3)2 at 80 and 125 ppm in hydroponics and agar media, demonstrated a high capacity to uptake lead. The results showed that the plants cultivated in agar accumulated 25563, 5534 and 2185 mg Pb kg-1 DW in roots, stems and leaves, respectively. Moreover, Pb concentrations found in hydroponically grown tumbleweed plants tissues were 30744, 1511 and 1421 mg kg-1 DW in roots, stems and leaves, respectively. It was observed that EDTA enhanced Pb translocation. No Pb phytotoxic effects were observed during the experimental time period. Cellular structural features were also observed using TEM.

  8. Saline gas-produced waters treatment with macrophytes in a hydroponic system. Final report, July 1, 1991-December 31, 1992

    SciTech Connect

    Jewell, W.J.; Albright, L.D.; Cummings, R.J.; Hicks, E.E.; Nock, T.D.

    1993-06-01

    A review of potential pollution problems of natural gas produced waters emphasized that present regulations do not adversely affect gas production, but future changes may be a concern (Fillo et al.). Also, the economics of the present treatment and disposal practices are becoming unacceptably high. Thus, new and more effective methods of treating and disposing of produced waters should be sought. A hydroponic system has been developed at Cornell University and piloted on domestic sewage partly with support from the Gas Research Institute, the U.S. Department of Energy (SERI), USEPA and New York State Energy Research and Development Authority (Jewell et al.). The hydroponic plant system is referred to as the 'Nutrient Film Technique' (NFT). The general goal of the project is to conduct a preliminary study to determine the feasibility of developing a biological treatment system capable of removing organic and inorganic pollutants from highly saline waters while minimizing the effluent volume by enhanced evapotranspiration.

  9. Uptake of cyantraniliprole into tomato fruit and foliage under hydroponic conditions: application to calibration of a plant/soil uptake model.

    PubMed

    Anderson, Jeffrey J; Bookhart, S Wingard; Clark, Jonathan M; Jernberg, Kathryn M; Kingston, Coleen K; Snyder, Nathan; Wallick, Kevin; Watson, Lawrence J

    2013-09-25

    Measured uptake of cyantraniliprole (3-bromo-1-(3-chloro-2-pyridinyl)-N-[4-cyano-2-methyl-6-[(methylamino)carbonyl]phenyl]-1H-pyrazole-5-carboxamide) into tomatoes following hydroponic exposure allowed calibration of a novel soil uptake model. The total mass of plant parts in treated plants was derived from the weights of successively harvested control plants (no cyantraniliprole provided) over 18 days following the first sampling of ripe tomatoes. Transpired water measured during plant growth was coupled with the calculated increase in plant mass to determine a transpiration coefficient constant (L/kg plant fresh weight) for use in the model. Cyantraniliprole concentrations in mature fruit, fresh foliage, and plant uptake solutions were used as the basis for a nonlinear least-squares optimization that consistently resolved to values that were empirically valid compared to metabolism studies in whole plants. This calibrated reference model adequately described uptake from soil pore water into plant fruit, and served as the basis for describing residues in fruit following commercial greenhouse growing conditions. PMID:24000775

  10. Cases of mercury exposure, bioavailability, and absorption.

    PubMed

    Gochfeld, Michael

    2003-09-01

    Mercury is a unique element that, unlike many metals, has no essential biological function. It is liquid at room temperature and is 13.6 times heavier than water. Its unique physical properties have been exploited for a variety of uses such as in mercury switches, thermostats, thermometers, and other instruments. Its ability to amalgamate with gold and silver are used in mining these precious metals and as a dental restorative. Its toxic properties have been exploited for medications, preservatives, antiseptics, and pesticides. For these reasons there have been many industrial uses of mercury, and occupational exposures of workers and industrial emissions and effluents contaminating air, water, soil, and ultimately food chains have long been a matter of great public health concern. This paper examines briefly six cases representing various forms of exposure to different species of mercury, and indicates the methodological issues in estimating exposure, bioavailability and absorption; these cases include Minamata disease in Japan, organic mercury poisoning in Iraq, methylmercury (MeHg) exposure in the Amazon, dimethylmercury (PMM) in the laboratory, an elemental mercury spill in Cajamarca, Peru, and a mercury-contaminated building in Hoboken, NJ, USA. Other scenarios that are not described include occupational exposure to mercury salts, mercurial preservatives in vaccines, cultural and ritualistic uses of mercury, and mercury in dental amalgams. PMID:12915150

  11. Maltodextrin based proniosomes of nateglinide: bioavailability assessment.

    PubMed

    Sahoo, Ranjan Ku; Biswas, Nikhil; Guha, Arijit; Kuotsu, Ketousetuo

    2014-08-01

    The present study delineates the fabrication of maltodextrin based proniosomes of nateglinide and their potential as controlled delivery system for diabetic therapy. New Zealand albino male rabbits have been used as animal model for in vivo study. To evaluate the bioavailability of nateglinide proniosome, a rapid, simple and sensitive HPLC method with photodiode array detection was developed and validated to determine nateglinide in rabbit plasma. Chromatographic separation was achieved by a reverse phase C18 column using a mixture of acetonitrile:methanol:10mM phosphate buffer (pH 3.5) in the ratio of 56:14:30 (%v/v) as the mobile phase at a flow rate of 1.0ml/min and quantified based on drug/IS peak area ratios. Gliclazide was used as the internal standard. The intra- and inter-day relative standard deviations of four tested concentrations were below 2%. The nateglinide proniosome formulation exhibited significantly higher plasma concentration than those of pure drug. The study revealed that the rate and extent of absorption of nateglinide from the proniosomal formulation was comparatively enhanced that of pure drug. Maltodextrin based proniosomes of nateglinide is not only simple and cost efficient delivery but also offers a useful and promising carrier for diabetic therapy through oral administration. PMID:24909314

  12. Bioavailability of caseinophosphopeptide-bound iron.

    PubMed

    Ait-Oukhatar, Nabil; Peres, Jean Michel; Bouhallab, Said; Neuville, Dominique; Bureau, Francois; Bouvard, Gerard; Arhan, Pierre; Bougle, Dominique

    2002-10-01

    Iron deficiency, one of the main worldwide nutritional deficiencies, results from the low bioavailability of most dietary iron, including cow milk. Hydrolysis of the cow milk protein casein produces low molecular weight caseinophosphopeptides (CPPs). Binding of iron to CPPs keeps it soluble in the digestive tract and prevents the formation of high molecular weight ferric hydroxides, which are poorly absorbed. Previous experimental studies have shown that iron bound to the phosphopeptide containing the first 25 amino acids of beta-casein, or beta-CN (1-25), is well absorbed and corrects efficiently iron deficiency. We sought to assess in vivo iron absorption and uptake by tissues involved in iron metabolism and storage (liver, spleen, bone marrow), using radiolabeled iron. beta-CN (1-25)-Fe displayed better absorption and tissue uptake by the vascularized rat loop model compared with a control substance, ferric ascorbate. The metabolism of beta-CN (1-25)-Fe labeled with iron 59, added to cow milk, was also studied in young women. Although the absorption of beta-CN (1-25)-Fe was not significantly higher than that of ferrous sulfate, it displayed significantly higher tissue uptake. This increase was transient and had disappeared by the 14th day of the study, suggesting that iron was used for metabolic purposes. PMID:12389027

  13. Enhanced bioavailability of raloxifene hydrochloride via dry suspensions prepared from drug/HP-β-cyclodextrin inclusion complexes.

    PubMed

    Lu, Rong; Liu, Shan; Wang, Qilin; Li, Xia

    2015-12-01

    This study aimed to develop a dry suspension formulation of raloxifene (RLX) using its HP-β-cyclodextrin inclusion complexes to enhance the oral bioavailability. Dry suspensions loading RLX/HP-β-cyclodextrin inclusion complexes (RLX-HICs) were prepared by solvent evaporation followed by a standard wet granulation process. The inclusion complexes were characterized by scanning electron microscopy, differential scanning calorimetry, and Fourier transform infrared spectroscopy. The features of dry suspensions such as dispersibility, flowability and dissolution were compared with conventional suspensions. Dry suspensions containing RLX-HICs dramatically increased the dissolution of RLX. Pharmacokinetic studies in rats showed that dry suspensions with RLX-HICs significantly enhanced the oral bioavailabilities of RLX. The absolute and relative bioavailabilities were up to 13.04% and 413.97% compared with the solution formulation (i.v.) and conventional suspensions (i.g.), respectively. The bioavailability improvement for dry suspensions with RLX-HICs can be attributed to improved dissolution and physiochemical properties of RLX, by which the overall absorption was enhanced. Dry suspensions prepared from RLX-HICs may be an attractive formulation for the oral delivery of RLX. PMID:26817276

  14. Bioavailability of intranasal promethazine dosage forms in dogs

    NASA Technical Reports Server (NTRS)

    Ramanathan, R.; Geary, R. S.; Bourne, D. W.; Putcha, L.

    1998-01-01

    Intramuscular promethazine (PMZ) is used aboard the US Space Shuttle to ameliorate symptoms of space motion sickness. Bioavailability after an oral dose of PMZ during space flight is thought to be impaired because of gastrointestinal disturbances associated with weightlessness and space motion sickness. In an attempt to find an alternative dosage form for use in space, we evaluated two intranasal (i.n.) dosage forms of PMZ in dogs for absorption and bioavailability relative to that of an equivalent intramuscular dose. Promethazine (5 mg kg-1) was administered as two intranasal dosage forms and as an intramuscular (i.m.) dose to three dogs in a randomised cross-over design. Serial blood samples were taken and analysed for PMZ concentrations and the absorption and bioavailability of PMZ were calculated for the three dosage forms. PMZ absorption from the carboxymethyl cellulose microsphere i.n. dosage form was more rapid and complete than from the myverol cubic gel formulation or from an i.m. injection. Bioavailability of the microsphere formulation was also greater than that of the gel formulation (AUC 3009 vs 1727 ng h ml-1). The bioavailability of the two i.n. dosage forms (relative to that of the i.m. injection) were 94% (microsphere) and 54% (gel). The i.n. microsphere formulation of PMZ offers great promise as an effective non-invasive alternative for treating space motion sickness due to its rapid absorption and bioavailability equivalent to the i.m. dose.

  15. Bioavailability enhancement of atovaquone using hot melt extrusion technology.

    PubMed

    Kate, Laxman; Gokarna, Vinod; Borhade, Vivek; Prabhu, Priyanka; Deshpande, Vinita; Pathak, Sulabha; Sharma, Shobhona; Patravale, Vandana

    2016-04-30

    Emerging parasite resistance and poor oral bioavailability of anti-malarials are the two cardinal issues which hinder the clinical success of malaria chemotherapy. Atovaquone-Proguanil is a WHO approved fixed dose combination used to tackle the problem of emerging resistance. However, Atovaquone is a highly lipophilic drug having poor aqueous solubility (less than 0.2 μg/ml) thus reducing its oral bioavailability. The aim of the present investigation was to explore hot melt extrusion (HME) as a solvent-free technique to enhance solubility and oral bioavailability of Atovaquone and to develop an oral dosage form for Atovaquone-Proguanil combination. Solid dispersion of Atovaquone was successfully developed using HME. The solid dispersion was characterized for DSC, FTIR, XRD, SEM, and flow properties. It was filled in size 2 hard gelatin capsules. The formulation showed better release as compared to Malarone® tablets, and 3.2-fold and 4.6-fold higher bioavailability as compared to Malarone® tablets and Atovaquone respectively. The enhanced bioavailability also resulted in 100% anti-malarial activity in murine infection model at 1/8(th) therapeutic dose. Thus the developed methodology shows promising potential to solve the problems associated with Atovaquone therapy, namely its high cost and poor oral bioavailability, resulting in increased therapeutic efficacy of Atovaquone. PMID:26969110

  16. Bioavailability enhancement strategies: basics, formulation approaches and regulatory considerations.

    PubMed

    Beg, Sarwar; Swain, Suryakanta; Rizwan, Md; Irfanuddin, Md; Malini, D Shobha

    2011-11-01

    Poor solubility remains a major challenge for pharmaceutical industry, which is now considered to be an area of prime importance in the field of biomedical research. Approximately 40% new molecular entities (NMEs) synthesized in pharmaceutical R with advanced combinatorial chemistry and computer aided drug designing (CADD) approaches suffer from poor solubility and bioavailability related issues. Apart from these presence of intestinal tight junctional epithelial cells, transporters and enzymatic barriers further reduces the oral absorption of drugs. Implication of the novel lipid based nanocarriers and nanomaterials like dendrimers and carbon nanotubes as a delivery system can effectively enhance the oral bioavailability of drugs by breaching the barriers, and resolve all critics related to solubility and bioavailability. Thus prime objectives of this review are to give in-depth knowledge and critical appraisal on the barriers for poor oral bioavailability of drugs, along with various novel formulation approaches used for bioavailability enhancement such as lipid based formulations, nanosizing techniques, complexation with polymers and nanomaterials like dendrimers, carbon nanotubes, and penetration enhancers. Also it gives a brief account on in vitro, in vivo screening methods used for assessment of oral bioavailability, and regulatory considerations for the approval. PMID:21864253

  17. Trace metal speciation and bioavailability in anaerobic digestion: A review.

    PubMed

    Thanh, Pham Minh; Ketheesan, Balachandran; Yan, Zhou; Stuckey, David

    2016-01-01

    Trace metals are essential for the growth of anaerobic microorganisms, however, in practice they are often added to anaerobic digesters in excessive amounts, which can lead to inhibition. The concept of bioavailability of metals in anaerobic digestion has been poorly understood in the past, and a lack of deep understanding of the relationship between trace metal speciation and bioavailability can result in ineffective metal dosing strategies for anaerobic digesters. Sequential extraction schemes are useful for fractionating trace metals into their different forms, and metal sulfides can serve as a store and source for trace metals during anaerobic digestion, while natural/synthetic chelating agents (soluble microbial products-SMPs, extracellular polysaccharides-EPS, and EDTA/NTA) are capable of controlling trace metal bioavailability. Nevertheless, more work is needed to: investigate the speciation and bioavailability of Ca, Mg, Mn, W, and Se; compare the bioavailability of different forms of trace metals e.g. carbonates, sulfides, phosphates to different anaerobic trophic groups; determine what factors influence metal sulfide dissolution; investigate whether chelating agents can increase trace metal bioavailability; develop and adapt specialized analytical techniques, and; determine how trace metal dynamics change in an anaerobic membrane bioreactor (AnMBR). PMID:26707985

  18. Manganese-mitigation of cadmium toxicity to seedling growth of Phytolacca acinosa Roxb. is controlled by the manganese/cadmium molar ratio under hydroponic conditions.

    PubMed

    Liu, Huimin; Zhang, Yuxiu; Chai, Tuanyao; Tan, Jinjuan; Wang, Jianwu; Feng, Shanshan; Liu, Geyu

    2013-12-01

    Manganese (Mn) can interact with cadmium (Cd) in environments and influence the toxic effect of Cd on plants. However, few studies have investigated the relationship between the Mn/Cd ratio and plant Cd-toxicity along Cd concentrations. In this paper, we studied the effects of external Mn/Cd molar ratios (0, 10, 30, 50 and 60) on Cd toxicity in the Mn hyperaccumulator and Cd tolerant plant, Phytolacca acinosa Roxb., at three Cd levels (50, 100 and 200 μM) under hydroponic conditions. Our result showed that seedling growth (y) under Cd stress was strongly positively related to the solution Mn/Cd molar ratio (SMCR). The relationship between the two variables under solution Cd concentrations was well explained by the linear regression model y=a+b1 (SMCR)+b2 (Solution-Cd). Increasing SMCR significantly reduced the Cd concentration and increased the Mn concentration in plant tissues. However, seedling growth was consistent with the shoot Mn/Cd molar ratio rather than with the Mn or Cd concentrations in plant tissues. At low levels of SMCR (e.g. 0 and 10), elevation of Mn distribution in shoot tissues might be a mechanism in P. acinosa seedlings to defend against Cd-toxicity. In comparison with low levels of SMCR, high levels of SMCR (e.g. 50 and 60) greatly alleviated lipid peroxidation and plant water-loss, and enhanced photosynthesis. However, the alleviated lipid peroxidation in the Mn-mitigation of Cd toxicity was likely to be the secondary effect resulting from the antagonism between Mn and Cd in the plant. PMID:24095921

  19. Dissolution of different zinc salts and zn uptake by Sedum alfredii and maize in mono- and co-cropping under hydroponic culture.

    PubMed

    Jiang, Cheng'ai; Wu, Qitang; Zeng, Shucai; Chen, Xian; Wei, Zebin; Long, Xinxian

    2013-09-01

    Previous soil pot and field experiments demonstrated that co-cropping the hyperaccumulator Sedum alfredii with maize increased Zn phytoextraction by S. alfredii and decreased Zn uptake by maize shoots. This hydroponic experiment was conducted to investigate whether the facilitation of Zn phytoextraction by S. alfredii resulted from improved dissolution in this co-cropping system and its relation to root exudates. S. alfredii and maize were mono- and co-cropped (without a root barrier) in nutrient solution spiked with four Zn compounds, ZnS, ZnO, Zn3(PO4)2 and 5ZnO x 2CO3-4H2O (represented as ZnCO3) at 1000 mg/L Zn for 15 days without renewal of nutrient solution after pre-culture. The root exudates were collected under incomplete sterilization and analyzed. The results indicated that the difference in Zn salts had a greater influence on the Zn concentration in maize than for S. alfredii, varying from 210-2603 mg/kg for maize shoots and 6445-12476 mg/kg for S. alfredii in the same order: ZnCO3 > ZnO > Zn3(PO4)2 > ZnS. For the four kinds of Zn sources in this experiment, co-cropping with maize did not improve Zn phytoextraction by S. alfredii. In most cases, compared to co-cropped and mono-cropped maize, mono-cropped S. alfredii resulted in the highest Zn2+ concentration in the remaining nutrient solution, and also had a higher total concentration of low molecular weight organic acids (LMWOA) and lower pH of root exudation. Root exudates did partly influence Zn hyperaccumulation in S. alfredii. PMID:24520733

  20. Development of suitable hydroponics system for phytoremediation of arsenic-contaminated water using an arsenic hyperaccumulator plant Pteris vittata.

    PubMed

    Huang, Yi; Miyauchi, Keisuke; Inoue, Chihiro; Endo, Ginro

    2016-01-01

    In this study, we found that high-performance hydroponics of arsenic hyperaccumulator fern Pteris vittata is possible without any mechanical aeration system, if rhizomes of the ferns are kept over the water surface level. It was also found that very low-nutrition condition is better for root elongation of P. vittata that is an important factor of the arsenic removal from contaminated water. By the non-aeration and low-nutrition hydroponics for four months, roots of P. vittata were elongated more than 500 mm. The results of arsenate phytofiltration experiments showed that arsenic concentrations in water declined from the initial concentrations (50 μg/L, 500 μg/L, and 1000 μg/L) to lower than the detection limit (0.1 μg/L) and about 80% of arsenic removed was accumulated in the fern fronds. The improved hydroponics method for P. vittata developed in this study enables low-cost phytoremediation of arsenic-contaminated water and high-affinity removal of arsenic from water. PMID:26549187

  1. Proliferation of Escherichia coli O157:H7 in Soil-Substitute and Hydroponic Microgreen Production Systems.

    PubMed

    Xiao, Zhenlei; Bauchan, Gary; Nichols-Russell, Lydia; Luo, Yaguang; Wang, Qin; Nou, Xiangwu

    2015-10-01

    Radish (Raphanus sativus var. longipinnatus) microgreens were produced from seeds inoculated with Escherichia coli O157:H7 by using peat moss-based soil-substitute and hydroponic production systems. E. coli populations on the edible and inedible parts of harvested microgreen plants (7 days postseeding) and in growth medium were examined. E. coli O157:H7 was shown to survive and proliferate significantly during microgreen growth in both production systems, with a higher level in the hydroponic production system. At the initial seed inoculation level of 3.7 log CFU/g, E. coli O157:H7 populations on the edible part of microgreen plants reached 2.3 and 2.1 log CFU/g (overhead irrigation and bottom irrigation, respectively) for microgreens from the soil-substitute production system and reached 5.7 log CFU/g for those hydroponically grown. At a higher initial inoculation of 5.6 log CFU/g seeds, the corresponding E. coli O157:H7 populations on the edible parts of microgreens grown in these production systems were 3.4, 3.6, and 5.3 log CFU/g, respectively. Examination of the spatial distribution of bacterial cells on different parts of microgreen plants showed that contaminated seeds led to systematic contamination of whole plants, including both edible and inedible parts, and seed coats remained the focal point of E. coli O157:H7 survival and growth throughout the period of microgreen production. PMID:26408126

  2. Improving Oral Bioavailability of Sorafenib by Optimizing the "Spring" and "Parachute" Based on Molecular Interaction Mechanisms.

    PubMed

    Liu, Chengyu; Chen, Zhen; Chen, Yuejie; Lu, Jia; Li, Yuan; Wang, Shujing; Wu, Guoliang; Qian, Feng

    2016-02-01

    Sorafenib is a clinically important oral tyrosine kinase inhibitor for the treatment of various cancers. However, the oral bioavailability of sorafenib tablet (Nexavar) is merely 38-49% relative to the oral solution, due to the low aqueous solubility of sorafenib and its relatively high daily dose. It is desirable to improve the oral bioavailability of sorafenib to expand the therapeutic window, reduce the drug resistance, and enhance patient compliance. In this study, we observed that the solubility of sorafenib could be increased ∼50-fold in the coexistence of poly(vinylpyrrolidone-vinyl acetate) (PVP-VA) and sodium lauryl sulfate (SLS), due to the formation of PVP-VA/SLS complexes at a lower critical aggregation concentration. The enhanced solubility provided a faster initial sorafenib dissolution rate, analogous to a forceful "spring" to release drug into solution, from tablets containing both PVP-VA and SLS. However, SLS appears to impair the ability of PVP-VA to act as an efficient "parachute" to keep the drug in solution and maintain drug supersaturation. Using 2D (1)H NMR, (13)C NMR, and FT-IR analysis, we concluded that the solubility enhancement and supersaturation of sorafenib were achieved by PVP-VA/SLS complexes and PVP-VA/sorafenib interaction, respectively, both through molecular interactions hinged on the PVP-VA VA groups. Therefore, a balance between "spring" and "parachute" must be carefully considered in formulation design. To confirm the in vivo relevance of these molecular interaction mechanisms, we prepared three tablet formulations containing PVP-VA alone, SLS alone, and PVP-VA/SLS in combination. The USP II in vitro dissolution and dog pharmacokinetic in vivo evaluation showed clear differentiation between these three formulations, and also good in vitro-in vivo correlation. The formulation containing PVP-VA alone demonstrated the best bioavailability with 1.85-fold and 1.79-fold increases in Cmax and AUC, respectively, compared with the

  3. Enhanced oral bioavailability of fenofibrate using polymeric nanoparticulated systems: physicochemical characterization and in vivo investigation

    PubMed Central

    Yousaf, Abid Mehmood; Kim, Dong Wuk; Oh, Yu-Kyoung; Yong, Chul Soon; Kim, Jong Oh; Choi, Han-Gon

    2015-01-01

    Background The intention of this research was to prepare and compare various solubility-enhancing nanoparticulated systems in order to select a nanoparticulated formulation with the most improved oral bioavailability of poorly water-soluble fenofibrate. Methods The most appropriate excipients for different nanoparticulated preparations were selected by determining the drug solubility in 1% (w/v) aqueous solutions of each carrier. The polyvinylpyrrolidone (PVP) nanospheres, hydroxypropyl-β-cyclodextrin (HP-β-CD) nanocorpuscles, and gelatin nanocapsules were formulated as fenofibrate/PVP/sodium lauryl sulfate (SLS), fenofibrate/HP-β-CD, and fenofibrate/gelatin at the optimized weight ratios of 2.5:4.5:1, 1:4, and 1:8, respectively. The three solid-state products were achieved using the solvent-evaporation method through the spray-drying technique. The physicochemical characterization of these nanoparticles was accomplished by powder X-ray diffraction, differential scanning calorimetry, scanning electron microscopy, and Fourier-transform infrared spectroscopy. Their physicochemical properties, aqueous solubility, dissolution rate, and pharmacokinetics in rats were investigated in comparison with the drug powder. Results Among the tested carriers, PVP, HP-β-CD, gelatin, and SLS showed better solubility and were selected as the most appropriate constituents for various nanoparticulated systems. All of the formulations significantly improved the aqueous solubility, dissolution rate, and oral bioavailability of fenofibrate compared to the drug powder. The drug was present in the amorphous form in HP-β-CD nanocorpuscles; however, in other formulations, it existed in the crystalline state with a reduced intensity. The aqueous solubility and dissolution rates of the nanoparticles (after 30 minutes) were not significantly different from one another. Among the nanoparticulated systems tested in this study, the initial dissolution rates (up to 10 minutes) were higher with

  4. Bioavailability of inorganic arsenic from bog ore-containing soil in the dog.

    PubMed Central

    Groen, K; Vaessen, H A; Kliest, J J; de Boer, J L; van Ooik, T; Timmerman, A; Vlug, R F

    1994-01-01

    In some parts of The Netherlands, bog ore-containing soils predominate, which have natural arsenic levels that exceed, by a factor of 10, existing standards for maximum allowable levels of inorganic arsenic in soil. These standards are based on the assumption that in humans the bioavailability of arsenic from ingested soil is equal to that from an aqueous solution. In view of the regulatory problem that the arsenic levels of these soils present, we questioned the validity of this assumption. To obtain a more realistic estimate, the bioavailability of inorganic arsenic from soil in a suitable animal model was studied. In this report, a study performed in six dogs in a two-way cross-over design is presented. The dogs received orally, in random order, arsenic both as an intravenous solution and as arsenic-containing soil. During a 120-hr period after administration urine was collected in 24-hr fractions. Levels of arsenic were determined using a method of wet digestion, isolation and complexation of arsine, followed by molecule absorption spectrometry. Within 120 hr after intravenous administration, 88 +/- 16% of the dose was excreted renally. After oral administration of arsenic-containing soil, only 7.0 +/- 1.5% was excreted renally. From the urinary excretion data for these two routes of administration, the calculated bioavailability of inorganic arsenic from soil was 8.3 +/- 2.0%. The results from this study demonstrate the need to reconsider the present risk assessment for arsenic in soil. Images Figure 1. Figure 2. PMID:8033848

  5. Enhanced oral bioavailability of docetaxel by lecithin nanoparticles: preparation, in vitro, and in vivo evaluation

    PubMed Central

    Hu, Kaili; Cao, Shan; Hu, Fuqiang; Feng, Jianfang

    2012-01-01

    The aim of this research work was to investigate the potential of lecithin nanoparticles (LNs) in improving the oral bioavailability of docetaxel. Docetaxel-loaded LNs (DTX-LNs) were prepared from oil-in-water emulsions and characterized in terms of morphology, size, zeta potential, and encapsulation efficiency. The in vitro release of docetaxel from the nanoparticles was studied by using dialysis bag method. Caco-2 cell monolayer was used for the in vitro permeation study of DTX-LNs. Bioavailability studies were conducted in rats and different pharmacokinetic parameters were evaluated after oral administration of DTX-LNs. The results showed that DTX-LNs had a mean diameter of 360 ± 8 nm and exhibited spherical shape with smooth surface under transmission electron microscopy. The DTX-LNs showed a sustained-release profile, with about 80% of docetaxel released within 72 hours. The apical to basolateral transport of docetaxel across the Caco-2 cell monolayer from the DTX-LNs was 2.14 times compared to that of the docetaxel solution (0.15 × 10−5 ± 0.016 × 10−5 cm/second versus 0.07 × 10−5 ± 0.003 × 10−5 cm/second). The oral bioavailability of the DTX-LNs was 3.65 times that of docetaxel solution (8.75% versus 2.40%). These results indicate that DTX-LNs were valuable as an oral drug delivery system to enhance the absorption of docetaxel. PMID:22848177

  6. Buccal films of prednisolone with enhanced bioavailability.

    PubMed

    Kumria, Rachna; Nair, Anroop B; Goomber, Garima; Gupta, Sumeet

    2016-01-01

    The conventional formulation of prednisolone is considered to be low in efficacy, primarily on account of their failure in providing and maintaining effective therapeutic drug levels. This study aims to focus on development of a mucoadhesive buccal delivery system with a twofold objective of offering a rapid as well as a prolonged delivery of prednisolone coupled with enhanced therapeutic efficacy. Buccoadhesive films of prednisolone were prepared by solvent-casting method using hydroxyl propyl methyl cellulose (K100), Carbopol 940 and/or Eudragit NE 40 D. Placebo films possessing the most desirable physicomechanical properties were selected for drug loading. The effect of polymer and its content on film properties, i.e. mucoadhesive strength, swelling and hydration, in vitro drug release was studied. Based on these studies, film F7D was selected for ex vivo permeation across porcine cheek mucosa. The steady state flux of prednisolone across the buccal mucosa was found to be 105.33 ± 32.07 µg/cm(2)/h. A comparative pharmacokinetic study of prepared film (F7D) and oral suspension of prednisolone was conducted. In vivo data of buccal film show greater bioavailability (AUC0-α: 24.26 ± 4.06 µg.h/ml versus 10.65 ± 2.15 µg.h/ml) and higher Cmax (2.70 ± 0.38 µg/ml versus 2.29 ± 0.32 µg/ml) value when compared to oral suspension. The data observed from this study highlight the feasibility of the buccal route as a viable option for delivery of prednisolone. PMID:24892626

  7. Contaminant bioavailability in soils, sediments, and aquatic environments

    PubMed Central

    Traina, Samuel J.; Laperche, Valérie

    1999-01-01

    The aqueous concentrations of heavy metals in soils, sediments, and aquatic environments frequently are controlled by the dissolution and precipitation of discrete mineral phases. Contaminant uptake by organisms as well as contaminant transport in natural systems typically occurs through the solution phase. Thus, the thermodynamic solubility of contaminant-containing minerals in these environments can directly influence the chemical reactivity, transport, and ecotoxicity of their constituent ions. In many cases, Pb-contaminated soils and sediments contain the minerals anglesite (PbSO4), cerussite (PbCO3), and various lead oxides (e.g., litharge, PbO) as well as Pb2+ adsorbed to Fe and Mn (hydr)oxides. Whereas adsorbed Pb can be comparatively inert, the lead oxides, sulfates, and carbonates are all highly soluble in acidic to circumneutral environments, and soil Pb in these forms can pose a significant environmental risk. In contrast, the lead phosphates [e.g., pyromorphite, Pb5(PO4)3Cl] are much less soluble and geochemically stable over a wide pH range. Application of soluble or solid-phase phosphates (i.e., apatites) to contaminated soils and sediments induces the dissolution of the “native” Pb minerals, the desorption of Pb adsorbed by hydrous metal oxides, and the subsequent formation of pyromorphites in situ. This process results in decreases in the chemical lability and bioavailability of the Pb without its removal from the contaminated media. This and analogous approaches may be useful strategies for remediating contaminated soils and sediments. PMID:10097045

  8. Distribution and bioavailability of Cr in central Euboea, Greece

    NASA Astrophysics Data System (ADS)

    Megremi, Ifigeneia

    2010-06-01

    Plants and soils from central Euboea, were analyzed for Cr(totai), Cr(VI), Ni, Mn, Fe and Zn. The range of metal concentrations in soils is typical to those developed on Fe-Ni laterites and ultramafic rocks. Their bioavailability was expressed in terms of concentrations extractable with EDTA and 1 M HNO3, with EDTA having a limited effect on metal recovery. Cr(VI) concentrations in soils evaluated by alkaline digestion solution were lower than phytotoxic levels. Chromium and Ni — and occasionally Zn — in the majority of plants were near or above toxicity levels. Cr(VI) concentrations in plants were extremely low compared to total chromium concentrations. Cr(total) in ground waters ranged from <1 μg.L-1 to 130 μg.L-1, with almost all chromium present as Cr(VI). With the exception of Cr(total) and in some cases Zn, all elements were below regulatory limits for drinking water. On the basis of Ca, Mg, Cr(total) and Si ground waters were classified into three groups: Group(I) with Cr concentrations less than 1 μg.L-1 from a karstic aquifer; Group(II) with average concentrations of 24 μg.L-1 of Cr and relatively high Si associated with ophiolites; and Group(III) with Cr concentrations of up to 130 μg.L-1, likely due to anthropogenic activity. Group(III) is comparable to ground waters from Assopos basin, characterized by high Cr(VI) concentrations, probably due to industrial actrivities.

  9. Influence of biochar amendments on marine sediment trace metal bioavailability

    NASA Astrophysics Data System (ADS)

    Gehrke, G. E.; Hsu-Kim, H.

    2014-12-01

    Biochar has become a desirable material for use in agricultural application to enhance soil quality and in-situ soil and sediment remediation to immobilize organic contaminants. We investigated the effects of biochar sediment amendments on the bioavailability of a suite of inorganic trace metals (Cr, Co, Ni, Cu, Zn, Pb) in contaminated sediments from multiple sites in Elizabeth River, VA. We incubated sediments in microcosms with a variety of water column redox and salinity conditions and compared sediments amended with two types of woody biochar to sediments amended with charcoal activated carbon and unamended sediments. We leached sediments in artificial gut fluid mimic of the benthic invertebrate Arenicola marina as a measure of bioavailability of the trace metals analyzed. In unamended anaerobic sediments, the gut fluid mimic leachable fraction of each trace metal is 1-4% of the total sediment concentration for each metal. Initial results indicate that in anaerobic microcosms, woody biochar sediment amendments (added to 5% dry wt) decrease the gut fluid mimic leachable fraction by 30-90% for all trace metals analyzed, and have comparable performance to charcoal activated carbon amendments. However, in microcosms without controlled redox conditions, woody biochar amendments increase the bioavailable fraction of Ni and Cu by up to 80%, while decreasing the bioavailable fraction of Co, Zn, and Pb by approximately 50%; charcoal activated carbon amendments decreased the bioavailability of all trace metals analyzed by approximately 20%. In microcosms without an overlying water column, biochar and activated carbon amendments had no significant effects on trace metal bioavailability. This research demonstrates that biochar can effectively decrease the bioavailability of trace metals in marine sediments, but its efficiency is metal-specific, and environmental conditions impact biochar performance.

  10. Where Does the Transformation of Precipitated Ceria Nanoparticles in Hydroponic Plants Take Place?

    PubMed

    Ma, Yuhui; Zhang, Peng; Zhang, Zhiyong; He, Xiao; Zhang, Junzhe; Ding, Yayun; Zhang, Jing; Zheng, Lirong; Guo, Zhi; Zhang, Lijuan; Chai, Zhifang; Zhao, Yuliang

    2015-09-01

    Cerium oxide nanoparticles (CeO2 NPs) have been found to be partly biotransformed from Ce(IV) to Ce(III) in plants, yet the transformation process and mechanism are not fully understood. Here, we try to clarify the specific site and necessary conditions for the transformation of precipitated CeO2 NPs in hydroponic cucumber plants. Three different treatment modes were adopted according to whether the NPs were incubated with roots all the time or not. Results showed that exposure modes significantly affect the translocation and transformation of CeO2 NPs. In the normal exposure mode, Ce was present as a Ce(IV) and Ce(III) mixture in the roots and shoots, and the proportion of Ce(III) in the shoots was enhanced obviously with the increase of exposure time. The results of short-time incubation and petiole exposure modes suggested that CeO2 NPs could not be reduced within a short incubation time (3 h) or be further reduced inside the plant tissues. It was deduced that root surfaces are the sites, and the physicochemical interaction between the NPs and root exudates at the nanobio interface is the necessary condition for the transformation of CeO2 NPs in plant systems. These results will contribute to understanding the transformation mechanism of CeO2 and other metal-based NPs and properly evaluate their ecological effects. PMID:26237071

  11. [Physiological response and bioaccumulation of Panax notoginseng to cadmium under hydroponic].

    PubMed

    Li, Zi-wei; Yang, Ye; Cui, Xiu-ming; Liao, Pei-ran; Ge, Jin; Wang, Cheng-xiao; Yang, Xiao-yan; Liu, Da-hui

    2015-08-01

    The physiological response and bioaccumulation of 2-year-old Panax notoginseng to cadmium stress was investigated under a hydroponic experiment with different cadmium concentrations (0, 2.5, 5, 10 μmol · L(-1)). Result showed that low concentration (2.5 μmol · L(-1)) of cadmium could stimulate the activities of SOD, POD, APX in P. notoginseng, while high concentration (10 μmol · L(-1)) treatment made activities of antioxidant enzyme descended obviously. But, no matter how high the concentration of cadmium was, the activities of CAT were inhibited. The Pn, Tr, Gs in P. notoginseng decreased gradually with the increase of cadmium concentration, however Ci showed a trend from rise to decline. The enrichment coefficients of different parts in P. notoginseng ranked in the order of hair root > root > rhizome > leaf > stem, and all enrichment coefficients decreased with the increase of concentration of cadmium treatments; while the cadmium content in different parts of P. notoginseng and the transport coefficients rose. To sum up, cadmium could affect antioxidant enzyme system and photosynthetic system of P. notoginseng; P. notoginseng had the ability of cadmium enrichment, so we should plant it in suitable place reduce for reducing the absorption of cadmium; and choose medicinal parts properly to lessen cadmium intake. PMID:26677685

  12. Structural analysis of Gossypium hirsutum fibers grown under greenhouse and hydroponic conditions.

    PubMed

    Natalio, Filipe; Tahir, Muhammad Nawaz; Friedrich, Norman; Köck, Margret; Fritz-Popovski, Gerhard; Paris, Oskar; Paschke, Reinhard

    2016-06-01

    Cotton is the one of the world's most important crops. Like any other crop, cotton growth/development and fiber quality is highly dependent on environmental factors. Increasing global weather instability has been negatively impacting its economy. Cotton is a crop that exerts an intensive pressure over natural resources (land and water) and demands an overuse of pesticides. Thus, the search for alternative cotton culture methods that are pesticide-free (biocotton) and enable customized standard fiber quality should be encouraged. Here we describe a culture of Gossypium hirsutum ("Upland" Cotton) utilizing a greenhouse and hydroponics in which the fibers are morphological similar to conventional cultures and structurally fit into the classical two-phase cellulose I model with 4.19nm crystalline domains surrounded by amorphous regions. These fibers exhibit a single crystalline form of cellulose I-Iß, monoclinic unit cell. Fiber quality bulk analysis shows an improved length, strength, whiteness when compared with soil-based cultures. Finally, we show that our fibers can be spun, used for production of non-woven fabrics and indigo-vat stained demonstrating its potential in industrial and commercial applications. PMID:26965558

  13. Effect of pyoverdine supply on cadmium and nickel complexation and phytoavailability in hydroponics.

    PubMed

    Ferret, C; Cornu, J Y; Elhabiri, M; Sterckeman, T; Braud, A; Jezequel, K; Lollier, M; Lebeau, T; Schalk, I J; Geoffroy, V A

    2015-02-01

    Siderophores are chelators with a high selectivity for Fe(III) and a good affinity for divalent metals, including Cd(II) and Ni(II). Inoculation with siderophore-producing bacteria (SPB) has thus been proposed as an alternative to chelator supply in phytoremediation. Accurate assessments of the potential of this association require a dissection of the interaction of siderophores with metals at the soil-root interface. This study focuses on pyoverdine (Pvd), the main siderophore produced by Pseudomonas aeruginosa. We first assessed the ability of Pvd to coordinate Ni(II). The stability constant of Pvd-Ni(II) (log K (L'Ni) = 10.9) was found to be higher than that of Pvd-Cd(II) (log K (L'Cd) = 8.2). We then investigated the effect of a direct supply of Pvd on the mobilization, speciation, and phytoavailability of Cd and Ni in hydroponics. When supplied at a concentration of 50 μM, Pvd selectively promoted Ni mobilization from smectite. It decreased plant Ni and Cd contents and the free ionic fractions of these two metals, consistent with the free ion activity model. Pvd had a more pronounced effect for Ni than for Cd, as predicted from its coordination properties. Inoculation with P. aeruginosa had a similar effect on Ni phytoavailability to the direct supply of Pvd. PMID:25167822

  14. Mercury localization and speciation in plants grown hydroponically or in a natural environment.

    PubMed

    Carrasco-Gil, Sandra; Siebner, Hagar; Leduc, Danika L; Webb, Samuel M; Millán, Rocío; Andrews, Joy C; Hernández, Luis E

    2013-04-01

    Better understanding of mercury (Hg) accumulation, distribution, and speciation in plants is required to evaluate potential risks for the environment and to optimize phytostabilization strategies for Hg-contaminated soils. The behavior of Hg in alfalfa (Medicago sativa) plants grown under controlled conditions in a hydroponic system (30 μM HgCl2) was compared with that of naturally occurring Horehound (Marrubium vulgare) plants collected from a mining soil polluted with Hg (Almadenejos, Spain) to characterize common mechanisms of tolerance. Synchrotron X-ray Fluorescence microprobe (μ-SXRF) showed that Hg accumulated at the root apex of alfalfa and was distributed through the vascular system to the leaves. Transmission electron microscopy (TEM) implied association of Hg with cell walls, accompanied by their structural changes, in alfalfa roots. Extended X-ray absorption fine structure (EXAFS) determined that Hg was principally bound to biothiols and/or proteins in M. sativa roots, stems, and leaves. However, the major fraction of Hg detected in M. vulgare plants consisted of mineral species, possibly associated with soil components. Interestingly, the fraction of Hg bound to biothiols/proteins (i.e., metabolically processed Hg) in leaves of both plants (alfalfa and M. vulgare) was similar, in spite of the big difference in Hg accumulation in roots, suggesting that some tolerance mechanisms might be shared. PMID:23406525

  15. Uptake and accumulation of antimicrobials, triclocarban and triclosan, by food crops in a hydroponic system.

    PubMed

    Mathews, Shiny; Henderson, Shannon; Reinhold, Dawn

    2014-05-01

    Commonly used in personal care products, triclocarban (TCC) and triclosan (TCS) are two chemicals with antimicrobial properties that have recently been recognized as environmental contaminants with the potential to adversely affect human health. The objective of the study described herein was to evaluate the potential of food crops to uptake TCC and TCS. Eleven food crops, grown in hydroponic nutrient media, were exposed to a mixture of 500 μg L(-1) TCC and TCS. After 4 weeks of exposure, roots accumulated 86-1,350 mg kg(-1) of antimicrobials and shoots had accumulated 0.33-5.35 mg kg(-1) of antimicrobials. Translocation from roots to shoots was less than 1.9 % for TCC and 3.7 % for TCS, with the greatest translocation for TCC observed for pepper, celery, and asparagus and for TCS observed for cabbage, broccoli, and asparagus. For edible tuber- or bulb-producing crops, the concentrations of both TCC and TCS were lower in the tubers than in the roots. Exposure calculations using national consumption data indicated that the average exposure to TCC and TCS from eating contaminated crops was substantially less than the exposure expected to cause adverse effects, but exceeded the predicted exposure from drinking water. Exposure to antimicrobials through food crops would be substantially reduced through limiting consumption of beets and onions. PMID:24464075

  16. Direct recycling of human hygiene water into hydroponic plant growth systems.

    PubMed

    Loader, C A; Garland, J L; Levine, L H; Cook, K L; Mackowiak, C L; Vivenzio, H R

    1999-01-01

    Direct recycling of gray water (human hygiene water) through plant production systems would reduce the need for additional space, mass, and energy for water reclamation in Advanced Life Support (ALS) systems. A plant production system designed to produce 25% of crew food needs could theoretically purify enough water through transpiration for 100% of crew water requirements. This scenario was tested through additions of shower and laundry water to recirculating hydroponic systems containing either wheat or soybean. Surfactant (Igepon TC-42) did not accumulate in the systems, and both the rate of surfactant disappearance and the proportion of Igepon-degrading microorganisms on the plant roots increased with time. A mechanism of surfactant degradation via the microbially ally mediated hydrolysis of the amide linkage and subsequent breakdown of fatty acid components is proposed. Fecal coliforms present in the human gray water were not detectable on the plant roots, indicating that human-associated microorganisms do not grow in the system. Overall plant growth was unaffected by gray water additions, although preliminary evidence suggests that reproduction may be inhibited. PMID:11542241

  17. Zn, Cd, S and trace metal bioaccumulation in willow (Salix spp.) cultivars grown hydroponically.

    PubMed

    McBride, M B; Martinez, C E; Kim, B

    2016-12-01

    Willows (Salix spp.) can be used to phytoremediate soils contaminated by Zn and Cd under certain conditions. In this study, the ability of 14 Salix cultivars to concentrate Cd, Zn and S in leaves was measured in hydroponic culture with 10 and 200 µM Cd and Zn, respectively, in the nutrient medium. The cultivars showed a wide range of biomass yields, tolerance to metals, and foliar concentrations of Zn and Cd, with some cultivars accumulating up to 1000 mg kg(-1) Zn, 70 mg kg(-1) Cd and 10,000 mg kg(-1) S with only mild phytotoxicity symptoms attributable to excess Zn. Cultivars with higher foliar Zn concentrations tended to have higher foliar Cd concentrations as well, and competition between Zn and Cd for uptake was observed. Exposure of Salix cultivars to Cd and Zn did not affect foliar concentrations of secondary metabolites such as polyphenols, but trace metal concentrations in leaves were significantly reduced (Fe and Cu) or increased (Mn) by exposure to excess Zn and Cd. Sulfur-XANES spectroscopy showed foliar S to be predominantly in highly oxidized (sulfate plus sulfonate) and reduced (thiol) forms, with oxidized S more prevalent in willows with the highest total S content. PMID:27216699

  18. The effects of plant diversity on nitrous oxide emissions in hydroponic microcosms

    NASA Astrophysics Data System (ADS)

    Sun, Hongying; Zhang, Chongbang; Song, Changchun; Chang, Scott X.; Gu, Baojing; Chen, Zhengxin; Peng, Changhui; Chang, Jie; Ge, Ying

    2013-10-01

    Previous studies have shown that plant diversity can improve the wastewater purification efficiency of constructed wetlands (CWs), but its effect on the nitrous oxide (N2O) emission in CWs has been unknown. To investigate the effect of plant diversity on the N2O emission, we established four plant species richness levels (each level containing 1, 2, 3 and 4 species, respectively) by using 96 hydroponic microcosms. Results showed that plant species richness enhanced the N2O emission, ranging from 27.1 to 115.4 μg N2O m-2 d-1, and improved nitrate removal (P < 0.001). The presence of Phalaris arundinacea within a given plant community increased the N2O emission (P < 0.001). The presence of Rumex japonicas had no influence on the N2O emissions (P > 0.05), but improved nitrogen removal (P < 0.001). Hence, our study highlights the importance of both plant species richness and species identity in mediating the N2O emission and nitrogen removal in CWs.

  19. Hydroponic Uptake of Atrazine and Lambda-cyhalothrin in Aquatic Macrophytes

    NASA Astrophysics Data System (ADS)

    Bouldin, J. L.; Farris, J. L.; Moore, M. T.; Smith, S.; Cooper, C. M.

    2005-05-01

    Phytoremediation encompasses an array of plant-associated processes known to mitigate contaminants from soil, sediment, and water. Modification of pesticides associated with agricultural runoff includes processes directly associated with aquatic macrophytes in addition to soil geochemical modifications and associated rhizospheric degradation. Remediation attributes of two vegetative species common to agricultural drainages in the Mississippi Delta, USA, were assessed using atrazine and lambda-cyhalothrin. Concentrations used in 8-d hydroponic exposures were calculated using recommended field applications and a 5% runoff model from a 0.65-cm rainfall event on a 2.02-ha field. While greater atrazine uptake was measured in Juncus effusus, greater lambda-cyhalothrin uptake occurred in Ludwigia peploides. Maximum pesticide uptake was reached within 48 h for each exposure and subsequent translocation of pesticides to upper plant biomass occurred in macrophytes exposed to atrazine. Sequestration of 98.2% of lambda-cyhalothrin in roots of L. peploides was measured after 8 d. Translocation of lambda-cyhalothrin in J. effusus resulted in 25.4% of pesticide uptake partitioned to upper plant biomass. These individual macrophyte remediation studies measured species- and pesticide-specific uptake rates, indicating that the seasonality of pesticide applications and macrophyte emergence might interact strongly to enhance mitigation capabilities in edge-of-field conveyance structures.

  20. Quality comparison of hydroponic tomatoes (Lycopersicon esculentum) ripened on and off vine

    NASA Technical Reports Server (NTRS)

    Arias, R.; Lee, T. C.; Specca, D.; Janes, H.

    2000-01-01

    There is a general belief that the quality of tomatoes ripened on vine is better than tomatoes ripened off the vine, influencing among other parameters, the price of this commodity. We compared the quality of hydroponic tomatoes ripened on and off vine by chemical, physical, and sensory evaluation to find what attributes are affected and to what extent. Lycopene, beta-carotene, total and soluble solids, moisture content, ascorbic acid, acidity, pH, texture, and color were analyzed. Tomatoes ripened on vine had significantly more lycopene, beta-carotene, soluble and total solids, higher a* and lower L*, and were firmer. However, a 100-judge panel rated only the color and overall liking of the vine-ripened tomatoes as more intense than the fruit ripened off vine. Therefore, the chemical and physical differences were mostly not large enough to influence the panelist's perception. The characterization of tomatoes ripened on and off vine may help to guide post-harvest handling and treatment and to improve the quality of tomatoes ripened off vine.

  1. Folate bioavailability from foods rich in folates assessed in a short term human study using stable isotope dilution assays.

    PubMed

    Mönch, Sabine; Netzel, Michael; Netzel, Gabriele; Ott, Undine; Frank, Thomas; Rychlik, Michael

    2015-01-01

    Different sources of folate may have different bioavailability and hence may impact the standard definition of folate equivalents. In order to examine this, a short term human study was undertaken to evaluate the relative native folate bioavailabilities from spinach, Camembert cheese and wheat germs compared to pteroylmonoglutamic acid as the reference dose. The study had a single-centre, randomised, four-treatment, four-period, four-sequence, cross-over design, i.e. the four (food) items to be tested (referred to as treatments) were administered in sequences according to the Latin square, so that each experimental treatment occurred only once within each sequence and once within each study period. Each of the 24 subjects received the four experimental items separated by a 14-day equilibrium phase and received a pteroylmonoglutamic acid supplement for 14 days before the first testing and between the testings for saturation of body pools. Folates in test foods, plasma and urine samples were determined by stable isotope dilution assays, and in urine and plasma, the concentrations of 5-methyltetrahydrofolate were evaluated. Standard non-compartmental methods were applied to determine the biokinetic parameters C(max), t(max) and AUC from baseline corrected 5-methyltetrahydrofolate concentrations within the interval from 0 to 12 hours. The variability of AUC and C(max) was moderate for spinach and oral solution of pteroylmonoglutamic acid but high for Camembert cheese and very high for wheat germs. The median t(max) was lowest for spinach, though t(max) showed a high variability among all treatments. When comparing the ratio estimates of AUC and C(max) for the different test foods, highest bioavailability was found for spinach followed by that for wheat germs and Camembert cheese. The results underline the dependence of folate bioavailability on the type of food ingested. Therefore, the general assumption of 50% bioavailability as the rationale behind the definition of

  2. A method for predicting bioavailability of rare earth elements in soils to maize.

    PubMed

    Wang, Wei-Sheng; Shan, Xiao-Quan; Wen, Bei; Zhang, Shu-Zhen

    2004-03-01

    A single-extraction procedure using low-molecular-weight organic acids (LMWOAs) as extractant and the first and second steps of a three-step extraction procedure recommended by the European Community Bureau of Reference (BCR; now European Community Standards, Measurement and Testing Programme, Brussels, Belgium) were performed to extract the light rare earth elements (LREEs) La, Ce, Pr, and Nd from wet rhizosphere soil. The extracted soil solutions were successively filtered through membranes with a pore size of less than 0.45 microm and a molecular weight cutoff of less than 1 kDa, which were termed colloidal and truly dissolved fractions, respectively. Apoplastically and symplastically bound LREEs in maize roots were experimentally distinguished by ultrasound-assisted desorption with 1 mM CaCl2 solution at 0 degrees C in ice-cooled water bath. When the LMWOAs extraction method was used, a good correlation was obtained between LREEs in soil colloidal and truly dissolved fractions and LREEs bound to apoplasm and symplasm of maize root. Both apoplastically and symplastically bound LREEs are the result of bioavailability. However, a poor correlation was obtained between LREEs in fractions water soluble, exchangeable and carbonate bound (B1) and Fe-Mn oxide bound (B2) of the BCR method and LREEs in apoplasm and symplasm and in intact roots. Hence, the LMWOAs extraction method is recommended for measuring the bioavailability of LREEs in soils. PMID:15285371

  3. Bioavailability to rats of iron in six varieties of wheat grain intrinsically labeled with radioiron

    SciTech Connect

    House, W.A.; Welch, R.M.

    1987-03-01

    Bioavailability to anemic rats of iron in six varieties of wheat grain was assessed by a whole-body radioassay procedure. Intrinsically labeled kernels were harvested from plants grown in /sup 59/Fe-labeled nutrient solutions. The varieties used were selected from 18 varieties of field-grown wheat grain that were analyzed for iron, protein and phytate content. Concentrations of iron, phytate and protein in grain of field-grown varieties ranged from 34 to 55 ppm, 0.7 to 1.2% dry wt and 11.3 to 15.4% dry wt, respectively. In grain from varieties grown in nutrient solutions, iron, phytate and protein concentrations ranged from 35 to 50 ppm, 1 to 1.2% dry wt, and 13.8 to 16.8% dry wt, respectively. Depending on the variety of intrinsically labeled grain fed in test meals to anemic rats (hemoglobin averaged 5.8 g/dL), absorption of /sup 59/Fe ranged from about 62 to 74% of the dose; differences among varieties were not significant (P greater than 0.05). Rats fed /sup 59/Fe-labeled FeCl/sub 3/ absorbed about 71% of the dose, which was similar to the average amount (69% of dose) absorbed by rats fed wheat. We concluded that selection of wheat varieties for increased yield or protein content has not adversely affected the bioavailability of iron in the grain.

  4. Bioavailability assessment of toxic metals using the technique "acid-volatile sulfide (AVS)-simultaneously extracted metals (SEM)" in marine sediments collected in Todos os Santos Bay, Brazil.

    PubMed

    Silva, Jucelino B; Nascimento, Rodrigo A; de Oliva, Sergio T; de Oliveira, Olívia M C; Ferreira, Sergio L C

    2015-10-01

    This paper reports the bioavailability of the metals (cadmium, copper, zinc, lead, and nickel) in sediment samples collected in seven stations from the São Paulo Estuary, Todos os Santos Bay, Brazil. The bioavailability was determined by employing the technique "acid-volatile sulfide (AVS) and simultaneously extracted metal (SEM)". The elements cadmium, copper, lead, and zinc were determined using differential pulse anodic stripping voltammetry (DPASV), while nickel was quantified utilizing electrothermal atomic absorption spectrometry (ET AAS). The accuracy of these methods was confirmed using a certified reference material of estuarine sediment (NIST 1646). The sulfide was quantified using potentiometry with selective electrode and the organic matter determination employing an indirect volumetric method using potassium dichromate and iron(II) sulfate solutions. The bioavailability of the metals was estimated by relationship between the concentration of AVS and the sum of the concentrations of the simultaneously extracted metals (ΣSEM), considering a significant toxicity when (ΣSEM)/(AVS) is higher than 1. The bioavailability values in the seven stations studied varied from 0.93 to 1.31 (June, 2014) and from 0.34 to 0.58 (September, 2014). These results demonstrated a critical condition of toxicity (bioavailability >1) in six of the seven sediment samples collected during the rainy season (June, 2014). In the other period (September, 2014), the bioavailability was always lower than 1 for all sediment samples collected in the seven stations. The individual values of the concentrations of the five metals were compared with the parameters PEL (probable effects level) and TEL (threshold effects level), which are commonly employed for characterization of ecological risk in environmental systems. This comparison revealed that all metals have concentrations lower than the PEL and only zinc and lead in some stations have contents higher than the TEL. The

  5. Bioaccessibility tests accurately estimate bioavailability of lead to quail.

    PubMed

    Beyer, W Nelson; Basta, Nicholas T; Chaney, Rufus L; Henry, Paula F P; Mosby, David E; Rattner, Barnett A; Scheckel, Kirk G; Sprague, Daniel T; Weber, John S

    2016-09-01

    Hazards of soil-borne lead (Pb) to wild birds may be more accurately quantified if the bioavailability of that Pb is known. To better understand the bioavailability of Pb to birds, the authors measured blood Pb concentrations in Japanese quail (Coturnix japonica) fed diets containing Pb-contaminated soils. Relative bioavailabilities were expressed by comparison with blood Pb concentrations in quail fed a Pb acetate reference diet. Diets containing soil from 5 Pb-contaminated Superfund sites had relative bioavailabilities from 33% to 63%, with a mean of approximately 50%. Treatment of 2 of the soils with phosphorus (P) significantly reduced the bioavailability of Pb. Bioaccessibility of Pb in the test soils was then measured in 6 in vitro tests and regressed on bioavailability: the relative bioavailability leaching procedure at pH 1.5, the same test conducted at pH 2.5, the Ohio State University in vitro gastrointestinal method, the urban soil bioaccessible lead test, the modified physiologically based extraction test, and the waterfowl physiologically based extraction test. All regressions had positive slopes. Based on criteria of slope and coefficient of determination, the relative bioavailability leaching procedure at pH 2.5 and Ohio State University in vitro gastrointestinal tests performed very well. Speciation by X-ray absorption spectroscopy demonstrated that, on average, most of the Pb in the sampled soils was sorbed to minerals (30%), bound to organic matter (24%), or present as Pb sulfate (18%). Additional Pb was associated with P (chloropyromorphite, hydroxypyromorphite, and tertiary Pb phosphate) and with Pb carbonates, leadhillite (a lead sulfate carbonate hydroxide), and Pb sulfide. The formation of chloropyromorphite reduced the bioavailability of Pb, and the amendment of Pb-contaminated soils with P may be a thermodynamically favored means to sequester Pb. Environ Toxicol Chem 2016;35:2311-2319. Published 2016 Wiley Periodicals Inc. on behalf of

  6. Selection of oral bioavailability enhancing formulations during drug discovery.

    PubMed

    Zheng, Weijia; Jain, Akash; Papoutsakis, Dimitris; Dannenfelser, Rose-Marie; Panicucci, Riccardo; Garad, Sudhakar

    2012-02-01

    The objective of this paper was to identify oral bioavailability enhancing approaches for a poorly water-soluble research compound during drug discovery stages using minimal amounts of material. LCQ789 is a pBCS (preclinical BCS) Class II compound with extremely low aqueous solubility (<1 µg/mL) and high permeability, therefore, resulting in very low oral bioavailability in preclinical species (rats and dogs). A number of solubility and/or dissolution enhancing approaches including particle size reduction, solid dispersions, lipid-based formulations and co-crystals, were considered in order to improve the compound's oral bioavailability. High-Throughput Screening (HTS) and in silico modeling (GastroPlus™) were utilized to minimize the compound consumption in early discovery stages. In vivo evaluation of selected physical form and formulation strategies was performed in rats and dogs. Amongst the formulation strategies, optimized solid dispersion and lipid-based formulation provided significant improvement in drug dissolution rate and hence, oral bioavailability. In addition, a significant impact of physical form on oral bioavailability of LCQ789 was observed. In conclusion, a thorough understanding of not only the formulation technique but also the physical form of research compounds is critical to ensure physical stability, successful pharmacokinetic (PK) profiling and early developability risk assessment. PMID:21851310

  7. Permeability Enhancers Dramatically Increase Zanamivir Absolute Bioavailability in Rats: Implications for an Orally Bioavailable Influenza Treatment

    PubMed Central

    Holmes, Eric H.; Devalapally, Harikrishna; Li, Libin; Perdue, Michael L.; Ostrander, Gary K.

    2013-01-01

    We have demonstrated that simple formulations composed of the parent drug in combination with generally regarded as safe (GRAS) permeability enhancers are capable of dramatically increasing the absolute bioavailability of zanamivir. This has the advantage of not requiring modification of the drug structure to promote absorption, thus reducing the regulatory challenges involved in conversion of an inhaled to oral route of administration of an approved drug. Absolute bioavailability increases of up to 24-fold were observed when Capmul MCM L8 (composed of mono- and diglycerides of caprylic/capric acids in glycerol) was mixed with 1.5 mg of zanamivir and administered intraduodenally to rats. Rapid uptake (tmax of 5 min) and a Cmax of over 7200 ng/mL was achieved. Variation of the drug load or amount of enhancer demonstrated a generally linear variation in absorption, indicating an ability to optimize a formulation for a desired outcome such as a targeted Cmax for enzyme saturation. No absorption enhancement was observed when the enhancer was given 2 hr prior to drug administration, indicating, in combination with the observed tmax, that absorption enhancement is temporary. This property is significant and aligns well with therapeutic applications to limit undesirable drug-drug interactions, potentially due to the presence of other poorly absorbed polar drugs. These results suggest that optimal human oral dosage forms of zanamivir should be enteric-coated gelcaps or softgels for intraduodenal release. There continues to be a strong need and market for multiple neuraminidase inhibitors for influenza treatment. Creation of orally available formulations of inhibitor drugs that are currently administered intravenously or by inhalation would provide a significant improvement in treatment of influenza. The very simple GRAS formulation components and anticipated dosage forms would require low manufacturing costs and yield enhanced convenience. These results are being utilized

  8. Assessment of relative bioavailability of heavy metals in soil using in vivo mouse model and its implication for risk assessment compared with bioaccessibility using in vitro assay.

    PubMed

    Kang, Yuan; Pan, Weijian; Liang, Siyun; Li, Ning; Zeng, Lixuan; Zhang, Qiuyun; Luo, Jiwen

    2016-10-01

    There is limited study to simultaneously determine the relative bioavailability of heavy metals such as Cd, Pb, Cu, Cr(VI), and Ni in soil samples. In the present study, the bioaccessibility of heavy metals using in vitro assay was compared with the relative bioavailability of heavy metals using in vivo mouse model. The bioaccessibility of heavy metals ranged from 9.05 ± 0.97 % (Cr) to 42.8 ± 3.52 % (Cd). The uptake profile of heavy metals in soil and solution samples in mouse revealed that the uptake kinetics could be fitted to a two-compartment model. The relative bioavailability of heavy meals ranged from 34.8 ± 7.0 % (Ni) to 131 ± 20.3 % (Cu). Poor correlation between bioaccessibility and relative bioavailability of heavy metals was observed (r (2) = 0.11, p > 0.05). The relative bioavailability of heavy metals was significantly higher than the bioaccessibility of heavy metals (p < 0.05). The present study indicated that the in vitro digestion method should be carefully employed in risk assessment. PMID:26603169

  9. Bioavailability of therapeutic proteins by inhalation--worker safety aspects.

    PubMed

    Pfister, Thomas; Dolan, David; Bercu, Joel; Gould, Janet; Wang, Bonnie; Bechter, Rudolf; Barle, Ester Lovsin; Pfannkuch, Friedlieb; Flueckiger, Andreas

    2014-08-01

    A literature review and analysis of inhalation bioavailability data for large therapeutic proteins was conducted in order to develop a practical estimate of the inhalation bioavailability of these drugs. This value is incorporated into equations used to derive occupational exposure limits(OELs) to protect biopharmaceutical manufacturing workers from systemic effects. Descriptive statistics implies that a value of 0.05, or 5% is an accurate estimate for large therapeutic proteins (molecular weight ≥ 40kDa). This estimate is confirmed by pharmacokinetic modeling of data from a human daily repeat-dose inhalation study of immunoglobulin G. In conclusion, we recommend using 5% bioavailability by inhalation when developing OELs for large therapeutic proteins. PMID:24958792

  10. Bioavailability of trace elements in surface sediments from Kongsfjorden, Svalbard.

    PubMed

    Grotti, Marco; Soggia, Francesco; Ianni, Carmela; Magi, Emanuele; Udisti, Roberto

    2013-12-15

    The bioavailability of trace elements in marine sediments from Kongsfjorden (Svalbard Islands, Norwegian Arctic) was assessed and discussed. Total concentrations of several elements were determined in two granulometric fractions and their bioavailability evaluated by both applying a sequential-selective extraction procedure and using a biomimetic approach based on proteolytic enzymes. Total concentration values and solid speciation patterns indicated overall that the anthropogenic impact of trace elements in the investigated area is negligible, although a minor enrichment with respect to crustal values was found for As, Cd, Cr, Ni, and V. Enrichment of trace elements in the <63-μm fraction compared to the coarser one was evident for As, Cd, Cr, and Ni. The evaluation of the bioavailable fractions showed that a large part of the total content of trace elements cannot enter the aquatic food chain and emphasised the risk of overestimating the environmental impact of heavy metals if the assessment is only based on total concentrations. PMID:24210011

  11. Rapid persulfate oxidation predicts PAH bioavailability in soils and sediments

    SciTech Connect

    Cuypers, C.; Grotenhuis, T.; Joziasse, J.; Rulkens, W.

    2000-05-15

    Persulfate oxidation was validated as a method to predict polycyclic aromatic hydrocarbon (PAH) bioavailability in soils and sediments. It was demonstrated for 14 field contaminated soils and sediments that residual PAH concentrations after a short (3 h) persulfate oxidation correspond well to residual PAH concentrations after 21 days of biodegradation. Persulfate oxidation of samples that had first been subjected to biodegradation yielded only limited additional PAH oxidation. This implies that oxidation and biodegradation removed approximately the same PAH fraction. Persulfate oxidation thus provides a good and rapid method for the prediction of PAH bioavailability. Thermogravimetric analysis of oxidized and untreated samples showed that persulfate oxidation primarily affected expanded organic matter. The results indicate that this expanded organic matter contained mainly readily bioavailable PAHs.

  12. Identification and origin of plant pathogenic microorganisms in recirculating nutrient solutions

    NASA Astrophysics Data System (ADS)

    Stanghellini, M. E.; Rasmussen, S. L.

    1994-11-01

    Avoidance of root-infecting microorganisms was originally considered one of the advantages of cultivation of crops in a soilless, recirculating nutrient solution. However, to date, four viral, three bacterial and 21 fungal pathogens have been identified as causal agents of root disease in hydroponically-grown crops. Root-infecting fungi, particularly those which produce a motile stage known as a zoospore, have been the primary pathogens associated with extensive crop losses. Documented sources of these root pathogens in hydroponic systems include peat, surface water such as rivers and streams, and insects. The severity of disease caused by these introduced root pathogens is primarily governed by the genetic susceptibility of each crop and the temperature of the recirculating nutrient solution.

  13. Bioavailability of HOC depending on the colloidal state of humic substances: a case study with PCB-77 and Daphnia magna.

    PubMed

    Gallé, T; Grégoire, Ch; Wagner, M; Bierl, R

    2005-10-01

    Condensed organic matter with higher affinity for hydrophobic organic compounds (HOC) is currently held responsible for slow desorption and concomitant lower bioavailabilities of HOC in sediments and soils. In an experiment with Daphnia magna and IHSS Peat Humic Acid (PHA), we showed that the bioconcentration factor (BCF) of 3,3',4,4'-tetrachlorobiphenyl (PCB-77) was directly related to the charge of the humic colloid, as predicted by the metal-humic binding model WHAM. Consistent with the type of binding to the humic acid (counter-ion accumulation vs. specific binding), increasing the concentration of Na+ and Ca2+ ions generated opposite effects on colloid charge and HOC binding by the humic acid. Condensation as a colloidal phenomenon in solution as well as on surfaces needs to be addressed as a contributor to lower bioavailabilities and, possibly, to slower desorption kinetics. PMID:15967482

  14. Dissolved Organic Matter Enhances Hg Bioavailability to a Hg-Methylating Bacterium Under Mildly Sulfidic Conditions

    NASA Astrophysics Data System (ADS)

    Graham, A. M.; Gilmour, C. C.

    2011-12-01

    Field studies have demonstrated a strong linkage between dissolved organic matter (DOM) quantity and quality and in-situ methylmercury (MeHg) production. The biogeochemical basis for these field observations is unknown however. Here, we investigate the roles of DOM and sulfide in controlling Hg bioavailability to the Hg-methylating bacterium Desulfovibrio desulfuricans ND132 in short-term washed cell assays. At environmentally relevant Hg/DOM ratios (2-4300 ng Hg/mg DOM), MeHg production increased linearly with increasing Suwannee River humic acid (SRHA) concentration, even in the presence of sulfide concentrations (5-10 μM) sufficient to outcompete SRHA for inorganic Hg. The DOM-dependent enhancement in Hg-methylation cannot be attributed to an enhancement of ND132 metabolic activity or alteration of Hg sorption to cells or bottle walls. Equilibrium speciation calculations indicated that cell suspensions were supersaturated with respect to metacinnabar (β-HgS(s)) and that Hg-DOM thiol complexes were relatively minor species. Notably, SRHA addition had no effect on Hg methylation in solutions where Hg-cysteine species predominated and β-HgS(s) precipitation was not predicted. We hypothesize that DOM enhances Hg-methylation by stabilizing HgS(s) colloids or nanoparticles against aggregation and/or by reducing the crystallinty of HgS(s) particles, and that such HgS(s) colloids are bioavailable to Hg-methylating bacteria. Ongoing work in the laboratory is evaluating the role of DOM character (size, aromaticity, reduced S content, etc.) in controlling the extent of the enhancement in MeHg production. These findings highlight the limits of equilibrium speciation approaches to predicting Hg bioavailability to methylating bacteria given the demonstrated significance of Hg-DOM-sulfide interactions in the anoxic environments where methylation occurs. Our laboratory experiments provide additional insight into the role that DOM plays in determining spatial and temporal

  15. Improved oral bioavailability of poorly water-soluble glimepiride by utilizing microemulsion technique.

    PubMed

    Li, Haiying; Pan, Tingting; Cui, Ying; Li, Xiaxia; Gao, Jiefang; Yang, Wenzhi; Shen, Shigang

    2016-01-01

    The objective of this work was to prepare an oil/water glimepiride (GM) microemulsion (ME) for oral administration to improve its solubility and enhance its bioavailability. Based on a solubility study, pseudoternary phase diagrams, and Box-Behnken design, the oil/water GMME formulation was optimized and prepared. GMME was characterized by dynamic laser light scattering, zeta potential, transmission electron microscopy, and viscosity. The in vitro drug release, storage stability, pharmacodynamics, and pharmacokinetics of GMME were investigated. The optimized GMME was composed of Capryol 90 (oil), Cremophor RH40 (surfactant), and Transcutol (cosurfactant), and increased GM solubility up to 544.6±4.91 µg/mL. The GMME was spherical in shape. The particle size and its polydispersity index were 38.9±17.46 nm and 0.266±0.057, respectively. Meanwhile, the GMME was physicochemically stable at 4°C for at least 3 months. The short-term efficacy in diabetic mice provided the proof that blood glucose had a consistent and significant reduction at a dose of 375 µg/kg whether via IP injection or IG administration of GMME. Compared with the glimepiride suspensions or glimepiride-meglumine complex solution, the pharmacokinetics of GMME in Wistar rats via IG administration exhibited higher plasma drug concentration, larger area under the curve, and more enhanced oral bioavailability. There was a good correlation of GMME between the in vitro release values and the in vivo oral absorption. ME could be an effective oral drug delivery system to improve bioavailability of GM. PMID:27540291

  16. Preparation and characterization of microemulsion of cilostazol for enhancement of oral bioavailability.

    PubMed

    Patel, Samir G; Rajput, Sadhana J; Groshev, Anastasia; Sutariya, Vijaykumar B

    2014-01-01

    Cilostazol is a promising drug for antiplatelet combination therapy that is very important for treatment for various cardiovascular disorders. However, oral delivery of this drug is greatly impeded by the poor solubility in aqueous solutions. The aim of this study was to develop microemulsion (ME) delivery system capable of improving the drug bioavailability. In this study, Capmul MCM C8 (glycerol monocaprylate) based MEs containing Tween 20(polysorbate 20) and/or Labrafil M 1944(poly oxyglycerides) as surfactant(S) and Transcutol P(diethyl glycol monoethyl ether) as cosurfactant(CoS) were studied as potential delivery systems of cilostazol. A number of such systems were prepared containing different S:CoS ratios(1:1, 2:1 and 3:1) based on phase diagrams. Loading of cilostazol was selected as per solubilization capacity and was characterized for pH, viscosity, conductivity, particle size, zeta potential and % transmittance. The MEs systems were further investigated for chemical stability, diffusion and bioavailability. Cilostazol displayed high solubility in microemulsions with particle size up to 70 nm. It was also stable at ambient temperature up to 6 months without significant change in particle size, zeta potential, and % transmittance. Dilution up to 100 fold with aqueous medium observed a visible cloudiness having a particle size up to 104 nm. The in vitro release, and ex vivo intraduodenal diffusion, and in vivo study indicated the capacity of developed ME to improve the bioavailability (1.43 fold) via oral route administration when compared with commercially available tablets (Pletoz-50). PMID:24274587

  17. [Absolute bioavailability of a special sustained-release acetylsalicylic acid formulation].

    PubMed

    Lücker, P W; Swoboda, M; Wetzelsberger, N

    1989-03-01

    Absolute Bioavailability of a Special Acetylsalicylic Acid Sustained Release Formulation. The absolute bioavailability of an acetylsalicylic acid (ASA) sustained release formulation (Contrheuma retard), containing 300 mg ASA as initial dose and 350 mg in a retard formulation, was determined in comparison to a standard ASA solution for intravenous administration in a two-treatment, two-period cross-over trial with 6 healthy male volunteers by comparing the areas under the plasma-fluctuation-time curves of the primary metabolite. In addition, it was examined by comparison of the mean times after administration of both formulations, whether the test formulation meets the requirements of a sustained release formulation. The investigations led to the following results: The absolute bioavailability of the test formulation was 95%. The statistical comparison of the areas under the concentration-time courses allowed no decision (neither for equivalence nor difference). The maximal concentration of SA after intravenous administration of the standard formulation was reached after 0.4 h on an average and amounted to 62 micrograms/ml. After oral administration of the test formulation, a mean concentration maximum of 28 micrograms/ml was calculated, which had been reached after about 2 h. The differences are statistically significant. The mean time for SA was 6 h after the standard formulation, whereas after administration of the test compound, a mean of 11.5 h was calculated. 24 h following administration, the concentration of SA was 1.3 micrograms/ml after intravenous administration of the standard formulation and 5.5 micrograms/ml after administration of the test formulation. These differences, too, are statistically significant. From the comparison of the mean time for SA, a retard factor of 1.9 was calculated. PMID:2757664

  18. Improved oral bioavailability of poorly water-soluble glimepiride by utilizing microemulsion technique

    PubMed Central

    Li, Haiying; Pan, Tingting; Cui, Ying; Li, Xiaxia; Gao, Jiefang; Yang, Wenzhi; Shen, Shigang

    2016-01-01

    The objective of this work was to prepare an oil/water glimepiride (GM) microemulsion (ME) for oral administration to improve its solubility and enhance its bioavailability. Based on a solubility study, pseudoternary phase diagrams, and Box–Behnken design, the oil/water GMME formulation was optimized and prepared. GMME was characterized by dynamic laser light scattering, zeta potential, transmission electron microscopy, and viscosity. The in vitro drug release, storage stability, pharmacodynamics, and pharmacokinetics of GMME were investigated. The optimized GMME was composed of Capryol 90 (oil), Cremophor RH40 (surfactant), and Transcutol (cosurfactant), and increased GM solubility up to 544.6±4.91 µg/mL. The GMME was spherical in shape. The particle size and its polydispersity index were 38.9±17.46 nm and 0.266±0.057, respectively. Meanwhile, the GMME was physicochemically stable at 4°C for at least 3 months. The short-term efficacy in diabetic mice provided the proof that blood glucose had a consistent and significant reduction at a dose of 375 µg/kg whether via IP injection or IG administration of GMME. Compared with the glimepiride suspensions or glimepiride-meglumine complex solution, the pharmacokinetics of GMME in Wistar rats via IG administration exhibited higher plasma drug concentration, larger area under the curve, and more enhanced oral bioavailability. There was a good correlation of GMME between the in vitro release values and the in vivo oral absorption. ME could be an effective oral drug delivery system to improve bioavailability of GM. PMID:27540291

  19. Microcrystalline preparation of akebia saponin D for its bioavailability enhancement in rats.

    PubMed

    Wang, Qiao-Han; Yang, Xiao-Lin; Xiao, Wei; Wang, Zhen-Zhong; Ding, Gang; Huang, Wen-Ze; Yang, Zhong-Lin; Zhang, Chun-Feng

    2015-01-01

    Akebia Saponin D (ASD) or asperosaponin VI is the most abundant constituent of the rhizome of Dipsacus asper, which has been used for the treatment of lower back pain, traumatic hematoma and bone fractures. In recent years, it was reported that ASD was a potential treatment strategy for Alzheimer's disease (AD). However, the low bioavailability of ASD limited its clinical utility. Microcrystalline preparation is one of the effective methods to improve drug absorption. The drugs prepared by different methods can present different solid forms (polymorphs), and different polymorphs have significantly different bioavailabilities. The objective of this study was to prepare ASD polymorphs using the different preparation processes and to evaluate their physicochemical properties and oral absorption. ASD-2 obtained by the antisolvent process was simpler and had higher recovery (78.5%) than that of ASD-1 by a two-step macroporous resin column separation (56.5%). The ASD polymorphs were characterized using differential scanning calorimetry (DSC), thermogravimetry analysis (TGA), powder X-ray diffraction (PXRD) and scanning electron microscopy (SEM). The results revealed that ASD-2 existed in microcrystalline form, while ASD-1 was amorphous. Furthermore, the equilibrium solubility, dissolution in aqueous solution and pharmacokinetic parameters of the samples were determined. ASD-2 showed lower aqueous solubility than that of ASD-1 (p < 0.01). In addition, ASD-2 showed lower dissolution with only 65% of the drug released while ASD-1 had a higher dissolution with 99% of drug released at the end of the 180 min testing period. Although ASD-1 significantly increased solubility and dissolution, the AUC 0-20h of ASD-2 was 4.3 times that of the amorphous ASD-1 in vivo. Data suggest that the microcrystalline preparation of ASD-2 is not only reasonable in economy and suitable for large-scale preparation, but also a promising method to enhance bioavailability of ASD. PMID:25936294

  20. Strategies to Quantify and Decrease Mercury Bioavailability and Methylation Potential in the Aquatic Environment

    NASA Astrophysics Data System (ADS)

    Hsu-Kim, H.; Deshusses, M.; Elias, D. A.

    2015-12-01

    Mercury (Hg) contamination in aquatic environments is a concern due to the production of monomethylmercury (MeHg), the highly bioaccumulative form that can impart neurotoxic effects to wildlife and humans. One strategy for remediation is to minimize MeHg production by anaerobic microorganisms that are prevalent in benthic settings. However, the factors that influence MeHg production and, in particular, the bioavailability of inorganic Hg for methylating microorganisms are poorly understood and difficult to quantify. This presentation will discuss the application of a thiol-based selective leaching assay to quantify the bioavailable fraction of Hg in sediments. This leaching assay involves quantification of leachable Hg concentrations in samples that are exposed to anoxic solutions containing glutathione (GSH). This thiol-based approach was chosen because cellular uptake and methylation of Hg by methylating bacteria are known to increase with the addition of GSH to cultures. This assay was applied to sediment-slurry microcosms that were amended with multiple types of inorganic Hg (dissolved Hg2+, Hg-sorbed to FeS, nanoparticulate HgS, microcrystalline HgS) that are known to span a range of bioavailability and methylation potential. The results demonstrated that the GSH-leachable Hg concentration correlated with MeHg production in cultures and microcosms. Methylation potential did not correlate to the concentration of Hg in the filtered aqueous fraction in the microcosm (i.e., passable though 0.2 um filters). These results suggest that a portion of the particle-bound Hg is available for methylation in a way that cannot be assessed by conventional filtration methods. The results of this work will be discussed in the context of management and in-situ remediation of contaminated sediments.

  1. Stabilisation of amorphous furosemide increases the oral drug bioavailability in rats.

    PubMed

    Nielsen, Line Hagner; Rades, Thomas; Müllertz, Anette

    2015-07-25

    A glass solution of the amorphous sodium salt of furosemide (ASSF) and polyvinylpyrrolidone (PVP) (80:20 w/w%) was prepared by spray drying. It was investigated if PVP was able to stabilise ASSF during storage and dissolution and whether this influenced the in vivo performance of the glass solution after oral dosing to rats. The glass solution had a glass transition temperature of 121.3 ± 0.5°C, which was significantly higher than that of the pure drug (101.2°C). ASSF in the glass solution was stable for at least 168 days when stored at 20°C and 0% relative humidity. The glass solution exhibited fast dissolution in simulated intestinal medium, pH 6.5; the intrinsic dissolution rate was found to be 10.1 ± 0.6 mg/cm(2)/min, which was significantly faster than the pure ASSF. When investigating the stability during dissolution in stimulated intestinal medium at pH 6.5, the ASSF in the glass solution showed signs of crystallinity after 1 min of dissolution, but crystallised to a lesser extent than pure ASSF. The stabilising effect of PVP on ASSF, led to improved relative oral bioavailability in rats of 263%, when compared to the pure ASSF. PMID:26026252

  2. The bioavailability of an orally administered medroxyprogesterone acetate suspension.

    PubMed

    Antal, E J; Gillespie, W R; Albert, K S

    1983-05-01

    The relative bioavailability of an orally administered aqueous suspension of medroxyprogesterone acetate (MPA) intended for intramuscular injection (Depo-Provera) was determined in relation to orally administered tablets. Serum levels of MPA were determined by radioimmunoassay following the administration of 400-mg doses to 19 adult male volunteers in a crossover design after an overnight fast. The two treatments were judged bioequivalent based upon a comparison of the resultant MPA serum levels and the derived bioavailability parameters. Hence, the intramuscular suspension administered orally offers an alternative means of achieving optimal serum levels of MPA in patients requiring high dose therapy. PMID:6222996

  3. Bioavailability of phytochemicals and its enhancement by drug delivery systems

    PubMed Central

    Aqil, Farrukh; Munagala, Radha; Jeyabalan, Jeyaprakash; Vadhanam, Manicka V.

    2013-01-01

    Issues of poor oral bioavailability of cancer chemopreventives have hindered progress in cancer prevention. Novel delivery systems that modulate the pharmacokinetics of existing drugs, such as nanoparticles, cyclodextrins, niosomes, liposomes and implants, could be used to enhance the delivery of chemopreventive agents to target sites. The development of new approaches in prevention and treatment of cancer could encompass new delivery systems for approved and newly investigated compounds. In this review, we discuss some of the delivery approaches that have already made an impact by either delivering a drug to target tissue or increasing its bioavailability by many fold. PMID:23435377

  4. Bioavailability of sediment-bound contaminants to marine organisms

    SciTech Connect

    Brown, B. |

    1993-09-01

    The bioavailability of sediment-bound contaminants to marine organisms indicates that there exists a potential for transfer of these contaminants through marine food webs to commercial fisheries products consumed by humans. However, there has been relatively little effort to combine and synthesize data on chemical/biological interactions between benthic animals and seagrasses and the sediments in which they reside on the one hand, and on the chemistry of bioaccumulation on the other. This report provides a conceptual basis for an approach to bioavailability and biomagnification of sediment-bound contaminants that reviews biological and chemical approaches.

  5. In Vivo Methods for the Assessment of Topical Drug Bioavailability

    PubMed Central

    Herkenne, Christophe; Alberti, Ingo; Naik, Aarti; Kalia, Yogeshvar N.; Mathy, François-Xavier; Préat, Véronique

    2007-01-01

    This paper reviews some current methods for the in vivo assessment of local cutaneous bioavailability in humans after topical drug application. After an introduction discussing the importance of local drug bioavailability assessment and the limitations of model-based predictions, the focus turns to the relevance of experimental studies. The available techniques are then reviewed in detail, with particular emphasis on the tape stripping and microdialysis methodologies. Other less developed techniques, including the skin biopsy, suction blister, follicle removal and confocal Raman spectroscopy techniques are also described. PMID:17985216

  6. The comparative bioavailability of cimetidine-alginate treatments.

    PubMed

    Britton, A M; Nichols, J D; Draper, P R

    1991-02-01

    The comparative bioavailability of cimetidine in cimetidine-alginate combinations has been investigated in twelve healthy volunteers in an open crossover study. Each volunteer received a single oral dose of a commercially available alginate-cimetidine combination tablet (Algitec) or cimetidine tablets (Tagamet), co-administered with a commercially available alginate reflux suppressant liquid or tablet (Gaviscon). No significant differences were observed between treatments for Cmax, tmax, AUC0-12 or AUC0- infinity. The study demonstrated equivalent bioavailability of cimetidine when administered separately with alginate products and as a fixed dose combination product. PMID:1672897

  7. Influence of food on the bioavailability of drugs.

    PubMed

    Melander, A

    1978-01-01

    Food intake exerts a complex influence on the bioavailability of drugs. It may interfere not only with tablet disintegration, drug dissolution and drug transit through the gastrointestinal tract, but may also affect the metabolic transformation of drugs in the gastrointestinal wall and in the liver. Different food components can have different effects, and food may interact in opposite ways, even with drugs that are chemically related. Therefore, the net effect of food on drug bioavailability can be predicted only by direct clinical studies of the drug in question. As judged mainly from single meal, single dose studies, food intake enhances the bioavailability of several different drugs, such as propranolol, metoprolol, hydrallazine, hydrochlorothiazide, canrenone (from spironolactone), nitrofurantoin, erythromycin (stearate), dicoumarol, phenytoin and carbamazepine, but reduces that of drugs such as isoniazid, rifampicin, tetracycline, penicillin and ampicillin, while having no consistent effect on the bioavailability of metronidazole, oxazepam, melperone, propylthiouracil, sulphasomidine and sulphonylureas. For some drugs such as digoxin and paracetamol, the rate but not the extent of absorption is reduced. Food may enhance bioavailability even though, or rather because, the rate of gastric emptying is reduced; this is apparently the case with hydrochlorothiazide and nitrofurantoin. The food induced enhancement of bioavailability of propranolol, metoprolol and hydrallazine is probably due to reduced first pass metabolism of these drugs, while food induced improvement of drug dissolution may explain the enhanced bioavailability of carbamazepine, canrenone, dicoumarol and phenytoin. An increased gastrointestinal pH may be in part the cause of the food induced reduction of the bioavailability of drugs such as isoniazid and tetracycline. In addition to single meal effects, repeated intake of protein-rich meals enhance, while carbohydrate-rich meals reduce, the rate

  8. Physiological modeling and assessments of regional drug bioavailability of danoprevir to determine whether a controlled release formulation is feasible.

    PubMed

    Reddy, Micaela B; Connor, Alyson; Brennan, Barbara J; Morcos, Peter N; Zhou, Amy; McLawhon, Pamela; Fretland, Adrian; Evans, Philip; Smith, Patrick; Tran, Jonathan Q

    2011-07-01

    Danoprevir, a potent, selective inhibitor of HCV NS3/4A protease, has a short half-life in humans. Therefore, the feasibility of a controlled release (CR) formulation to allow less frequent dosing was investigated using experimental approaches and physiological modeling to examine whether danoprevir is absorbed in the colon. Danoprevir absorption was studied in portal-vein-cannulated monkeys and in monkeys surgically modified to make intraduodenal, intrajejunal, intracolonic and oral administration possible. In portal-vein-cannulated monkeys, absorption was apparent up to 24 h after administration. The observed relative bioavailability from intracolonic delivery in the monkey was approximately 30% relative to oral administration, consistent with the model prediction of 40%. Human relative bioavailability for a tablet delivered to the colon compared with an immediate release (IR) formulation was predicted to be 4-28%. Preclinical data and modeling suggested that CR development would be challenging for this Biopharmaceutics Classification System Class IV compound. Therefore, a confirmative study in healthy volunteers was conducted to investigate the relative bioavailability of danoprevir in various regions of the gastrointestinal tract. In a randomized, open-label, crossover study, subjects received 100 mg danoprevir IR soft gel capsule, 100 mg danoprevir solution delivered to the distal small bowel and colon via an Enterion™ capsule (a remotely activated capsule for regional drug delivery) and 100 mg danoprevir powder to the colon via an Enterion™ capsule. The relative bioavailability of danoprevir (compared with IR) delivered to the colon was 6.5% for a solution and 0.6% for a powder formulation, indicating that a CR formulation is not feasible. PMID:21660978

  9. Lead toxicity, defense strategies and associated indicative biomarkers in Talinum triangulare grown hydroponically.

    PubMed

    Kumar, Abhay; Prasad, M N V; Sytar, Oksana

    2012-11-01

    Talinum species have been used to investigate a variety of environmental problems for e.g. determination of metal pollution index and total petroleum hydrocarbons in roadside soils, stabilization and reclamation of heavy metals (HMs) in dump sites, removal of HMs from storm water-runoff and green roof leachates. Species of Talinum are popular leaf vegetables having nutrient antinutrient properties. In this study, Talinum triangulare (Jacq.) Willd (Ceylon spinach) grown hydroponically were exposed to different concentrations of lead (Pb) (0, 0.25, 0.5, 0.75, 1.0 and 1.25 mM) to investigate the biomarkers of toxicity and tolerance mechanisms. Relative water content, cell death, photosynthetic pigments, sulphoquinovosyldiacylglycerol (SQDG), anthocyanins, α-tocopherol, malondialdehyde (MDA), reactive oxygen species (ROS) glutathione (GSH and GSSG) and elemental analysis have been investigated. The results showed that Pb in roots and shoots gradually increased as the function of Pb exposure; however Pb concentration in leaves was below detectable level. Chlorophylls and SQDG contents increased at 0.25 mM of Pb treatment in comparison to control at all treated durations, thereafter decreased. Levels of carotenoid, anthocyanins, α-tocopherol, and lipid peroxidation increased in Pb treated plants compared to control. Water content, cells death and elemental analysis suggested the damage of transport system interfering with nutrient transport causing cell death. The present study also explained that Pb imposed indirect oxidative stress in leaves is characterized by decreases in GSH/GSSG ratio with increased doses of Pb treatment. Lead-induced oxidative stress was alleviated by carotenoids, anthocyanins, α-tocopherol and glutathione suggesting that these defense responses as potential biomarkers for detecting Pb toxicity. PMID:22722003

  10. (137)Cs and (90)Sr uptake by sunflower cultivated under hydroponic conditions.

    PubMed

    Soudek, Petr; Valenová, Sárka; Vavríková, Zuzana; Vanek, Tomás

    2006-01-01

    The (90)Sr and (137)Cs uptake by the plant Helianthus annuus L. was studied during cultivation in a hydroponic medium. The accumulation of radioactivity in plants was measured after 2, 4, 8, 16 and 32 days of cultivation. About 12% of (137)Cs and 20% of (90)Sr accumulated during the experiments. We did not find any differences between the uptake of radioactive and stable caesium and strontium isotopes. Radioactivity distribution within the plant was determined by autoradiography. (137)Cs was present mainly in nodal segments, leaf veins and young leaves. High activity of (90)Sr was localized in leaf veins, stem, central root and stomata. The influence of stable elements or analogues on the transfer behaviour was investigated. The percentage of non-active caesium and strontium concentration in plants decreased with the increasing initial concentration of Cs or Sr in the medium. The percentage of (90)Sr activity in plants decreased with increasing initial activity of the nuclide in the medium, but the activity of (137)Cs in plants increased. The influence of K(+) and NH(4)(+) on the uptake of (137)Cs and the influence of Ca(2+) on the uptake of (90)Sr was tested. The highest accumulation of (137)Cs (24-27% of the initial activity of (137)Cs) was found in the presence of 10 mM potassium and 12 mM ammonium ions. Accumulation of about 22% of initial activity of (90)Sr was determined in plants grown on the medium with 8 mM calcium ions. PMID:16630674

  11. Effects of cadmium on cork oak (Quercus suber L.) plants grown in hydroponics.

    PubMed

    Gogorcena, Yolanda; Larbi, Ajmi; Andaluz, Sofia; Carpena, Ramón O; Abadía, Anunciación; Abadía, Javier

    2011-12-01

    Cork oak (Quercus suber L.) is an autochthonous tree species that is being used for reforestation in heavy-metal-contaminated areas in Spain. A hydroponics experiment was carried out to characterize the effects of Cd on several morphological and physiological parameters in this species, including shoot length, nutrient concentrations and allocation in different organs, leaf pigment concentrations, photosynthetic efficiency, root ferric chelate reductase (FCR) activity and organic acid concentrations in xylem sap. Four different Cd treatments were applied, adding Cd chelated with EDTA or as chloride salt at two different concentrations (10 and 50 µM Cd). After 1 month of Cd treatment, plant growth was significantly inhibited in all treatments. Results indicate that Cd accumulates in all organs 7- to 500-fold when compared with control plants. The highest Cd concentration was found in the 50 µM CdCl(2) treatment, which led to concentrations of ~30, 123 and 1153 µg Cd g(-1) dry weight in leaves, stems and roots, respectively. In the strongest Cd treatments the concentrations of P and Ca decreased in some plant parts, whereas the Mn leaf concentrations decreased with three of the four Cd treatments applied. The concentrations of chlorophyll and carotenoids on an area basis decreased, whereas the (zeaxanthin plus antheraxanthin)/(total violaxanthin cycle carotenoids) ratio and the non-photochemical quenching increased significantly in all Cd treatments. Cadmium treatments caused significant increases in the activity of the enzyme FCR in roots and in the concentrations of organic acids in xylem sap. Some of the physiological changes found support the fact that Cd induces a deficiency of Fe in cork oak, although the plant Fe concentrations were not reduced significantly. At higher concentrations the effects of Cd were more pronounced, and were more marked when Cd was in the free ion form than when present in the form of Cd-EDTA. PMID:22121153

  12. Increased sensitivity to salt stress in tocopherol-deficient Arabidopsis mutants growing in a hydroponic system

    PubMed Central

    Ellouzi, Hasna; Hamed, Karim Ben; Cela, Jana; Müller, Maren; Abdelly, Chedly; Munné-Bosch, Sergi

    2013-01-01

    Recent studies suggest that tocopherols could play physiological roles in salt tolerance but the mechanisms are still unknown. In this study, we analyzed changes in growth, mineral and oxidative status in vte1 and vte4 Arabidopsis thaliana mutants exposed to salt stress. vte1 and vte4 mutants lack α-tocopherol, but only the vte1 mutant is additionally deficient in γ-tocopherol. Results showed that a deficiency in vitamin E leads to reduced growth and increased oxidative stress in hydroponically-grown plants. This effect was observed at early stages, not only in rosettes but also in roots. The vte1 mutant was more sensitive to salt-induced oxidative stress than the wild type and the vte4 mutant. Salt sensitivity was associated with (i) high contents of Na+, (ii) reduced efficiency of PSII photochemistry (Fv/Fm ratio) and (iii) more pronounced oxidative stress as indicated by increased hydrogen peroxide and malondialdeyde levels. The vte 4 mutant, which accumulates γ- instead of α-tocopherol showed an intermediate sensitivity to salt stress between the wild type and the vte1 mutant. Contents of abscisic acid, jasmonic acid and the ethylene precursor, 1-aminocyclopropane-1-carboxylic acid were higher in the vte1 mutant than the vte4 mutant and wild type. It is concluded that vitamin E-deficient plants show an increased sensitivity to salt stress both in rosettes and roots, therefore indicating the positive role of tocopherols in stress tolerance, not only by minimizing oxidative stress, but also controlling Na+/K+ homeostasis and hormonal balance. PMID:23299430

  13. Increased sensitivity to salt stress in tocopherol-deficient Arabidopsis mutants growing in a hydroponic system.

    PubMed

    Ellouzi, Hasna; Hamed, Karim Ben; Cela, Jana; Müller, Maren; Abdelly, Chedly; Munné-Bosch, Sergi

    2013-02-01

    Recent studies suggest that tocopherols could play physiological roles in salt tolerance but the mechanisms are still unknown. In this study, we analyzed changes in growth, mineral and oxidative status in vte1 and vte4 Arabidopsis thaliana mutants exposed to salt stress. vte1 and vte4 mutants lack α-tocopherol, but only the vte1 mutant is additionally deficient in γ-tocopherol. Results showed that a deficiency in vitamin E leads to reduced growth and increased oxidative stress in hydroponically-grown plants. This effect was observed at early stages, not only in rosettes but also in roots. The vte1 mutant was more sensitive to salt-induced oxidative stress than the wild type and the vte4 mutant. Salt sensitivity was associated with (i) high contents of Na(+), (ii) reduced efficiency of PSII photochemistry (Fv/Fm ratio) and (iii) more pronounced oxidative stress as indicated by increased hydrogen peroxide and malondialdeyde levels. The vte 4 mutant, which accumulates γ- instead of α-tocopherol showed an intermediate sensitivity to salt stress between the wild type and the vte1 mutant. Contents of abscisic acid, jasmonic acid and the ethylene precursor, 1-aminocyclopropane-1-carboxylic acid were higher in the vte1 mutant than the vte4 mutant and wild type. It is concluded that vitamin E-deficient plants show an increased sensitivity to salt stress both in rosettes and roots, therefore indicating the positive role of tocopherols in stress tolerance, not only by minimizing oxidative stress, but also controlling Na(+)/K(+) homeostasis and hormonal balance. PMID:23299430

  14. Mutants with enhanced nitrogenase activity in hydroponic Azospirillum brasilense-wheat associations.

    PubMed

    Pereg Gerk, L; Gilchrist, K; Kennedy, I R

    2000-05-01

    The effect of a mutation affecting flocculation, differentiation into cyst-like forms, and root colonization on nitrogenase expression by Azospirillum brasilense is described. The gene flcA of strain Sp7 restored these phenotypes in spontaneous mutants of both strains Sp7 and Sp245. Employing both constitutive pLA-lacZ and nifH-lacZ reporter fusions expressed in situ, the colony morphology, colonization pattern, and potential for nitrogenase activity of spontaneous mutants and flcA Tn5-induced mutants were established. The results of this study show that the ability of Sp7 and Sp245 mutant strains to remain in a vegetative form improved their ability to express nitrogenase activity in association with wheat in a hydroponic system. Restoring the cyst formation and colonization pattern to the spontaneous mutant Sp7-S reduced nitrogenase activity rates in association with plants to that of the wild-type Sp7. Although Tn5-induced flcA mutants showed higher potentials for nitrogenase expression than Sp7, their potentials were lower than that of Sp7-S, indicating that other factors in this strain contribute to its exceptional nitrogenase activity rates on plants. The lack of lateral flagella is not one of these factors, as Sp7-PM23, a spontaneous mutant impaired in swarming and lateral-flagellum production but not in flocculation, showed wild-type nitrogenase activity and expression. The results also suggest factors of importance in evolving an effective symbiosis between Azospirillum and wheat, such as increasing the availability of microaerobic niches along the root, increased supply of carbon sources by the plant, and the retention of the bacterial cells in vegetative form for faster metabolism. PMID:10788397

  15. Internalization and Dissemination of Human Norovirus and Animal Caliciviruses in Hydroponically Grown Romaine Lettuce

    PubMed Central

    DiCaprio, Erin; Ma, Yuanmei; Purgianto, Anastasia; Hughes, John

    2012-01-01

    Fresh produce is a major vehicle for the transmission of human norovirus (NoV) because it is easily contaminated during both pre- and postharvest stages. However, the ecology of human NoV in fresh produce is poorly understood. In this study, we determined whether human NoV and its surrogates can be internalized via roots and disseminated to edible portions of the plant. The roots of romaine lettuce growing in hydroponic feed water were inoculated with 1 × 106 RNA copies/ml of a human NoV genogroup II genotype 4 (GII.4) strain or 1 × 106 to 2 × 106 PFU/ml of animal caliciviruses (Tulane virus [TV] and murine norovirus [MNV-1]), and plants were allowed to grow for 2 weeks. Leaves, shoots, and roots were homogenized, and viral titers and/or RNA copies were determined by plaque assay and/or real-time reverse transcription (RT)-PCR. For human NoV, high levels of viral-genome RNA (105 to 106 RNA copies/g) were detected in leaves, shoots, and roots at day 1 postinoculation and remained stable over the 14-day study period. For MNV-1 and TV, relatively low levels of infectious virus particles (101 to 103 PFU/g) were detected in leaves and shoots at days 1 and 2 postinoculation, but virus reached a peak titer (105 to 106 PFU/g) at day 3 or 7 postinoculation. In addition, human NoV had a rate of internalization comparable with that of TV as determined by real-time RT-PCR, whereas TV was more efficiently internalized than MNV-1 as determined by plaque assay. Taken together, these results demonstrated that human NoV and animal caliciviruses became internalized via roots and efficiently disseminated to the shoots and leaves of the lettuce. PMID:22729543

  16. Deciphering Phosphate Deficiency-Mediated Temporal Effects on Different Root Traits in Rice Grown in a Modified Hydroponic System

    PubMed Central

    Negi, Manisha; Sanagala, Raghavendrarao; Rai, Vandna; Jain, Ajay

    2016-01-01

    Phosphate (Pi), an essential macronutrient for growth and development of plant, is often limiting in soils. Plants have evolved an array of adaptive strategies including modulation of root system architecture (RSA) for optimal acquisition of Pi. In rice, a major staple food, RSA is complex and comprises embryonically developed primary and seminal roots and post-embryonically developed adventitious and lateral roots. Earlier studies have used variant hydroponic systems for documenting the effects of Pi deficiency largely on primary root growth. Here, we report the temporal effects of Pi deficiency in rice genotype MI48 on 15 ontogenetically distinct root traits by using easy-to-assemble and economically viable modified hydroponic system. Effects of Pi deprivation became evident after 4 days- and 7 days-treatments on two and eight different root traits, respectively. The effects of Pi deprivation for 7 days were also evident on different root traits of rice genotype Nagina 22 (N22). There were genotypic differences in the responses of primary root growth along with lateral roots on it and the number and length of seminal and adventitious roots. Notably though, there were attenuating effects of Pi deficiency on the lateral roots on seminal and adventitious roots and total root length in both these genotypes. The study thus revealed both differential and comparable effects of Pi deficiency on different root traits in these genotypes. Pi deficiency also triggered reduction in Pi content and induction of several Pi starvation-responsive (PSR) genes in roots of MI48. Together, the analyses validated the fidelity of this modified hydroponic system for documenting Pi deficiency-mediated effects not only on different traits of RSA but also on physiological and molecular responses. PMID:27200025

  17. Deciphering Phosphate Deficiency-Mediated Temporal Effects on Different Root Traits in Rice Grown in a Modified Hydroponic System.

    PubMed

    Negi, Manisha; Sanagala, Raghavendrarao; Rai, Vandna; Jain, Ajay

    2016-01-01

    Phosphate (Pi), an essential macronutrient for growth and development of plant, is often limiting in soils. Plants have evolved an array of adaptive strategies including modulation of root system architecture (RSA) for optimal acquisition of Pi. In rice, a major staple food, RSA is complex and comprises embryonically developed primary and seminal roots and post-embryonically developed adventitious and lateral roots. Earlier studies have used variant hydroponic systems for documenting the effects of Pi deficiency largely on primary root growth. Here, we report the temporal effects of Pi deficiency in rice genotype MI48 on 15 ontogenetically distinct root traits by using easy-to-assemble and economically viable modified hydroponic system. Effects of Pi deprivation became evident after 4 days- and 7 days-treatments on two and eight different root traits, respectively. The effects of Pi deprivation for 7 days were also evident on different root traits of rice genotype Nagina 22 (N22). There were genotypic differences in the responses of primary root growth along with lateral roots on it and the number and length of seminal and adventitious roots. Notably though, there were attenuating effects of Pi deficiency on the lateral roots on seminal and adventitious roots and total root length in both these genotypes. The study thus revealed both differential and comparable effects of Pi deficiency on different root traits in these genotypes. Pi deficiency also triggered reduction in Pi content and induction of several Pi starvation-responsive (PSR) genes in roots of MI48. Together, the analyses validated the fidelity of this modified hydroponic system for documenting Pi deficiency-mediated effects not only on different traits of RSA but also on physiological and molecular responses. PMID:27200025

  18. EFFECTS OF DIFFERENT FORMS OF ORGANIC CARBON ON THE PARTITIONING AND BIOAVAILABILITY OF NONPHENYL

    EPA Science Inventory

    Oxygenated nonpolar organic contaminants (NOCs) are underrepresented in studies of the partitioning and bioavailability of NOCs, including nonylphenol. In this investigation, we evaluated the toxicity, partitioning, and bioavailability of nonylphenol as affected by different form...

  19. COMPETITIVE INFLUENCE OF PHOSPHORUS AND CALCIUM ON PB IN-VITRO BIOAVAILABILITY

    EPA Science Inventory

    The bioavailability of a metal is heavily related to the speciation of the particular metal. Further, the complexity of examining metal bioavailability is compounded by the presence of competitive ions. Thus, equally contaminated soils with varying concentrations of competitive e...

  20. FIELD EVALUATION OF THE IN-SITU TREATMENTS TO REDUCE SOIL LEAD BIOAVAILABILITY: CONCLUSIONS

    EPA Science Inventory

    This presentation summarizes the conclusion of the technical issues associated with the Pb bioavailability experiment which IINERT has been conducting and further to illustrate that although bioavailability is a simple concept, its measurement and the implementation of the measur...

  1. Relative Bioavailability and Bioaccessability and Speciation of Arsenic in Contaminated Soils

    EPA Science Inventory

    Background: Assessment of soil arsenic (As) bioavailability may profoundly affect the extent of remediation required at contaminated sites by improving human exposure estimates. Because small adjustments in soil As bioavailability estimates can significantly alter risk assessment...

  2. Increased calcium bioavailability in mice fed genetically engineered plants lacking calcium oxalate

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bioavailable calcium affects bone formation and calcification. Here we investigate how a single gene mutation altering calcium partitioning in the model forage crop Medicago truncatula affects calcium bioavailability. Previously, the cod5 M. truncatula mutant was identified which contains identical ...

  3. A system and methodology for measuring volatile organic compounds produced by hydroponic lettuce in a controlled environment

    NASA Technical Reports Server (NTRS)

    Charron, C. S.; Cantliffe, D. J.; Wheeler, R. M.; Manukian, A.; Heath, R. R.

    1996-01-01

    A system and methodology were developed for the nondestructive qualitative and quantitative analysis of volatile emissions from hydroponically grown 'Waldmann's Green' leaf lettuce (Lactuca sativa L.). Photosynthetic photon flux (PPF), photoperiod, and temperature were automatically controlled and monitored in a growth chamber modified for the collection of plant volatiles. The lipoxygenase pathway products (Z)-3-hexenal, (Z)-3-hexenol, and (Z)-3-hexenyl acetate were emitted by lettuce plants after the transition from the light period to the dark period. The volatile collection system developed in this study enabled measurements of volatiles emitted by intact plants, from planting to harvest, under controlled environmental conditions.

  4. 21 CFR 320.27 - Guidelines on the design of a multiple-dose in vivo bioavailability study.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ..., DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS FOR HUMAN USE BIOAVAILABILITY AND BIOEQUIVALENCE REQUIREMENTS Procedures for Determining the Bioavailability or Bioequivalence of Drug Products §...

  5. 21 CFR 320.27 - Guidelines on the design of a multiple-dose in vivo bioavailability study.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ..., DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS FOR HUMAN USE BIOAVAILABILITY AND BIOEQUIVALENCE REQUIREMENTS Procedures for Determining the Bioavailability or Bioequivalence of Drug Products §...

  6. Effects of combined composting and vermicomposting of waste sludge on arsenic fate and bioavailability.

    PubMed

    Maňáková, Blanka; Kuta, Jan; Svobodová, Markéta; Hofman, Jakub

    2014-09-15

    Composting and vermicomposting are traditional processes for the treatment of sludge. During these processes, the humification of organic matter has a significant effect on the physicochemical form and distribution of heavy metals. In this study, industrial sludge (groundwater treatment waste) contaminated by arsenic (396 ± 1 mg kg(-1)) was used. Such sludge poses a significant challenge with respect to effective treatment. Composting, vermicomposting (with Eisenia fetida), and the combined approach of composting and vermicomposting were performed to determine the evolution of arsenic speciation, mobility and bioavailability. The composting/vermicomposting was done with sludge, horse manure, and grass in the ratios of 3:6:1. A solution of 0.1M NH4COOCH3 was used as a single extraction solvent for determination of the mobile arsenic pool and targeted arsenic species (As(III), As(V), monomethylarsenic acid - MMA(V), dimethylarsenic acid - DMA(V)). The analysis of arsenic in the extracts was carried out by means of HPLC-ICP-MS spectrometry. In addition, the earthworm species E. fetida was used for bioaccumulation tests that followed the compost and vermicompost processes. The obtained results indicate a reduction in arsenic mobility and bioavailability in all matured composts and vermicomposts. The combined process exhibited a greater effect than compost or vermicompost alone. PMID:25209831

  7. Genetically modified Pseudomonas biosensing biodegraders to detect PCB and chlorobenzoate bioavailability and biodegradation in contaminated soils

    PubMed Central

    Liu, Xuemei; Germaine, Kieran J; Ryan, David

    2010-01-01

    Whole cell microbial biosensors offer excellent possibilities for assaying the complex nature of the bioavailable and bioaccessible fraction of pollutants in contaminated soils, which currently cannot be easily addressed. This paper describes the application and evaluation of three microbial biosensor strains designed to detect the bioavailability and biodegradation of PCBs (and end-products) in contaminated soils and sediments. Polychlorinated biphenyls (PCBs) are considered to be one of the most wide spread, hazardous and persistent pollutants. Herein we describe that there was a positive correlation between the PCB levels within the samples and the percentage of biosensor cells that were expressing their reporter gene; gfp. Immobilisation of the biosensors in calcium alginate beads allowed easy and accurate detection of the biosensor strains in contaminated soil and sludge samples. The biosensors also showed that PCB degradation activity was occurring at a much greater level in Pea inoculated planted soil compared to inoculated unplanted soil indicating rhizoremediation (the removal of pollutants by plant root associated microbes) shows considerable promise as a solution for removing organic xenobiotics from the environment. PMID:21326926

  8. [Role of ABC efflux transporters in the oral bioavailability and drug-induced intestinal toxicity].

    PubMed

    Yokooji, Tomoharu

    2013-01-01

    The gastrointestinal tract is the organ that absorbs nutrients and water from foods and drinks. This organ is often exposed to various harmful xenobiotics, and therefore possesses various detoxification/barrier systems, including metabolizing enzymes and efflux transporters. Intestinal epithelial cells express ATP-binding cassette (ABC) efflux transporters such as P-glycoprotein, multidrug resistance-associated proteins (MRPs) and breast cancer resistance protein, in addition to various solute carrier (SLC) influx transporters. These transporters are expressed site- and membrane-specifically in enterocytes, which affects the bioavailability of ingested substrate drugs. Expression and/or function of transporters can be modulated by various compounds, including therapeutic drugs, herbal products, some foods, and by disease states. The modulation of transporters could cause unexpectedly higher or lower blood concentrations, marked inter- and intra-individual variations in pharmacokinetics, and unreliable pharmacological actions in association with toxicities of substrates. Recently, we found that hyperbilirubinemia, which occurs in some disease states, increased intestinal accumulation and toxicity of methotrexate, an MRP substrate, because of the suppression of MRP function by high plasma concentrations of conjugated bilirubin. We also attempted to ameliorate the intestinal toxicity of irinotecan hydrochloride by modulating the hepatic and intestinal functions of MRP2. This review summarizes our findings regarding the role of ABC transporters, especially MRPs, in oral bioavailability and in drug-induced intestinal toxicity. Our approach to treat intestinal toxicity using an MRP2 modulator is also described. PMID:23811769

  9. Speciation and Bioavailability Measurements of Environmental Plutonium Using Diffusion in Thin Films.

    PubMed

    Cusnir, Ruslan; Steinmann, Philipp; Christl, Marcus; Bochud, François; Froidevaux, Pascal

    2015-01-01

    The biological uptake of plutonium (Pu) in aquatic ecosystems is of particular concern since it is an alpha-particle emitter with long half-life which can potentially contribute to the exposure of biota and humans. The diffusive gradients in thin films technique is introduced here for in-situ measurements of Pu bioavailability and speciation. A diffusion cell constructed for laboratory experiments with Pu and the newly developed protocol make it possible to simulate the environmental behavior of Pu in model solutions of various chemical compositions. Adjustment of the oxidation states to Pu(IV) and Pu(V) described in this protocol is essential in order to investigate the complex redox chemistry of plutonium in the environment. The calibration of this technique and the results obtained in the laboratory experiments enable to develop a specific DGT device for in-situ Pu measurements in freshwaters. Accelerator-based mass-spectrometry measurements of Pu accumulated by DGTs in a karst spring allowed determining the bioavailability of Pu in a mineral freshwater environment. Application of this protocol for Pu measurements using DGT devices has a large potential to improve our understanding of the speciation and the biological transfer of Pu in aquatic ecosystems. PMID:26574673

  10. Speciation and Bioavailability Measurements of Environmental Plutonium Using Diffusion in Thin Films

    PubMed Central

    Cusnir, Ruslan; Steinmann, Philipp; Christl, Marcus; Bochud, François; Froidevaux, Pascal

    2015-01-01

    The biological uptake of plutonium (Pu) in aquatic ecosystems is of particular concern since it is an alpha-particle emitter with long half-life which can potentially contribute to the exposure of biota and humans. The diffusive gradients in thin films technique is introduced here for in-situ measurements of Pu bioavailability and speciation. A diffusion cell constructed for laboratory experiments with Pu and the newly developed protocol make it possible to simulate the environmental behavior of Pu in model solutions of various chemical compositions. Adjustment of the oxidation states to Pu(IV) and Pu(V) described in this protocol is essential in order to investigate the complex redox chemistry of plutonium in the environment. The calibration of this technique and the results obtained in the laboratory experiments enable to develop a specific DGT device for in-situ Pu measurements in freshwaters. Accelerator-based mass-spectrometry measurements of Pu accumulated by DGTs in a karst spring allowed determining the bioavailability of Pu in a mineral freshwater environment. Application of this protocol for Pu measurements using DGT devices has a large potential to improve our understanding of the speciation and the biological transfer of Pu in aquatic ecosystems. PMID:26574673

  11. Formulation of 20(S)-protopanaxadiol nanocrystals to improve oral bioavailability and brain delivery.

    PubMed

    Chen, Chen; Wang, Lisha; Cao, Fangrui; Miao, Xiaoqing; Chen, Tongkai; Chang, Qi; Zheng, Ying

    2016-01-30

    The aim of this study was to fabricate 20(S)-protopanaxadiol (PPD) nanocrystals to improve PPD's oral bioavailability and brain delivery. PPD nanocrystals were fabricated using an anti-solvent precipitation approach where d-α-tocopheryl polyethylene glycol 1000 succinate (TPGS) was optimized as the stabilizer. The fabricated nanocrystals were nearly spherical with a particle size and drug loading of 90.44 ± 1.45 nm and 76.92%, respectively. They are in the crystalline state and stable at 4°C for at least 1 month. More than 90% of the PPD could be rapidly released from the nanocrystals, which was much faster than the physical mixture and PPD powder. PPD nanocrystals demonstrated comparable permeability to solution at 2.52 ± 0.44×10(-5)cm/s on MDCK monolayers. After oral administration of PPD nanocrystals to rats, PPD was absorbed quickly into the plasma and brain with significantly higher Cmax and AUC0-t compared to those of the physical mixture. However, no brain targeting was observed, as the ratios of the plasma AUC0-t to brain AUC0-t for the two groups were similar. In summary, PPD nanocrystals are a potential oral delivery system to improve PPD's poor bioavailability and its delivery into the brain for neurodegenerative disease and intracranial tumor therapies in the future. PMID:26680316

  12. Evaluation of epoxiconazole bioavailability in soil to the earthworm Aporrectodea icterica.

    PubMed

    Nélieu, S; Delarue, G; Ollivier, E; Awad, P; Fraillon, F; Pelosi, C

    2016-02-01

    In soil, the determination of total concentration using an exhaustive extraction method has little relevance to evaluate the exposure of an organism to a chemical, because of sorption processes. This study aims to propose a mild extraction method to evaluate the bioavailability of the fungicide epoxiconazole to the earthworm Aporrectodea icterica. Experiments were conducted in soils presenting various textures and organic carbon contents, spiked with formulated epoxiconazole 7 to 56 days prior to their extraction. In parallel, the epoxiconazole concentration was determined in exposed earthworms and the fungicide's effects were evaluated by measuring weight gain, enzymatic activities and total protein contents. Among the various mild chemical solvents tested to evaluate the environmental availability of the fungicide, the 50 mM hydroxypropyl-β-cyclodextrin solution allowed to extract around 30% of epoxiconazole. This percentage corresponded to the ratio determined in exposed A. icterica under similar soil conditions. Furthermore, this mild method was demonstrated to be sensitive to soil sorption capacities and to ageing. The mild extraction method was then applied to explore the relationship between total and (bio)available concentrations in soil and in A. icterica, over 7- or 28-day exposure time. This demonstrated the proportionality between epoxiconazole concentration in earthworm and available in soil (up to 96%, with regression coefficient R(2) = 0.98). Sublethal effects on earthworm remained not significant. PMID:26315591

  13. Bioavailability of detomidine administered sublingually to horses as an oromucosal gel.

    PubMed

    Kaukinen, H; Aspegrén, J; Hyyppä, S; Tamm, L; Salonen, J S

    2011-02-01

    The objective of the study was to determine the absorption, bioavailability and sedative effect of detomidine administered to horses as an oromucosal gel compared to intravenous and intramuscular administration of detomidine injectable solution. The study was open and randomized, with three sequences crossover design. Nine healthy horses were given 40 μg/kg detomidine intravenously, intramuscularly or administered under the tongue with a 7-day wash-out period between treatments. Blood samples were collected before and after drug administration for the measurement of detomidine concentrations in serum. The effects of the route of administration on heart rate and rhythm were evaluated and the depth of sedation assessed. Mean (±SD) bioavailability of detomidine was 22% (±5.3%) after sublingual administration and 38.2% (±7.9%) after intramuscular administration. The sedative effects correlated with detomidine concentrations regardless of the route of administration. We conclude that less detomidine is absorbed when given sublingually than when given intramuscularly, because part of it does not reach the circulation. Sublingual administration of detomidine oromucosal gel at 40 μg/kg produces safe sedation in horses. Slow absorption leads to fewer and less pronounced adverse effects than the more rapid absorption after intramuscular injection. PMID:21219348

  14. Development of solid lipid nanoparticles as carriers for improving oral bioavailability of glibenclamide.

    PubMed

    Gonçalves, L M D; Maestrelli, F; Di Cesare Manelli, L; Ghelardini, C; Almeida, A J; Mura, P

    2016-05-01

    A solid lipid nanoparticle (SLN) formulation was developed with the aim of improving the oral bioavailability and the therapeutic effectiveness of glibenclamide (GLI), a poorly water-soluble drug used in the treatment of type 2 diabetes. The SLN was prepared using different lipid components (Precirol® and Compritol®) and preparation procedures. Precirol-based SLN, obtained with the emulsion of solvent evaporation technique gave the best results and was selected for drug loading. Addition of lecithin to the SLN core or PEG coating was effective in increasing the nanoparticles stability in simulated gastric solution. Both such formulations were stable after one month storage at 5±3°C, exhibited the absence of in vitro cytotoxicity, and presented a similar in vitro prolonged-release, reaching 100% release after 24h. The lecithin-containing GLI-loaded SLN formulation, selected for in vivo studies in virtue of its higher EE% than the PEG-coated formulation (70.3% vs 19.6%), showed a significantly stronger hypoglycemic effect with respect to the drug alone, in terms of both shorter onset time and longer duration of the effect. These positive results indicated that the proposed SLN approach was successful in improving GLI oral bioavailability, confirming its potential as an effective delivery system for a suitable therapy of diabetes. PMID:26925503

  15. Specific and quantitative assessment of naphthalene and salicylate bioavailability by using a bioluminescent catabolic reporter bacterium

    SciTech Connect

    Heitzer, A.; Thonnard, J.E.; Sayler, G.S.; Webb, O.F. )

    1992-06-01

    A bioassay was developed and standardized for the rapid, specific, and quantitative assessment of naphthalene and salicylate bioavailability by use of bioluminescence monitoring of catabolic gene expression. The bioluminescent reporter strain Pseudomonas fluorescens HK44, which carries a transcriptional nahG-luxCDABE fusion for naphthalene and salicylate catabolism, was used. The physiological state of the reporter cultures as well as the intrinsic regulatory properties of the naphthalene degradation operon must be taken into account to obtain a high specificity at low target substrate concentrations. Experiments have shown that the use of exponentially growing reporter cultures has advantages over the use of carbon-starved, resting cultures. In aqueous solutions for both substrates, naphthalene and salicylate, linear relationships between initial substrate concentration and bioluminescence response were found over concentration ranges of 1 to 2 orders of magnitude. Naphthalene could be detected at a concentration of 45 ppb. Studies conducted under defined conditions with extracts and slurries of experimentally contaminated sterile soils and identical uncontaminated soil controls demonstrated that this method can be used for specific and quantitative estimations of target pollutant presence and bioavailability in soil extracts and for specific and qualitative estimations of napthalene in soil slurries.

  16. Distribution and chemical forms of copper in the root cells of castor seedlings and their tolerance to copper phytotoxicity in hydroponic culture.

    PubMed

    Kang, Wei; Bao, Jianguo; Zheng, Jin; Hu, Hongqin; Du, Jiangkun

    2015-05-01

    The subcellular localization and chemical forms of copper in castor (Ricinus communis L.) seedlings grown in hydroponic nutrient solution were identified by chemical extraction, transmission electron microscopy, and Fourier transform infrared spectroscopy. The wild castor seeds were harvested from an abandoned copper mine in Tonglu Mountain, Daye City of Hubei Province, China. The results revealed that (1) the seedlings grew naturally in MS liquid medium with 40.00 mg kg(-1) CuSO4, in which the seedling growth rate and biomass index were 0.14 and 1.23, respectively, which were the highest values among all the treatments. The copper content in castor seedlings increased along with elevated CuSO4 concentration in the medium, reaching a maximum value of 16 570.12 mg kg(-1)(DW) when exposed to 60.00 mg L(-1) CuSO4, where 91.31% of the copper was accumulated in roots. (2) The copper existed in various chemical forms in the roots of the castor seedlings. Copper of 67.66% was extracted from the components of cell walls, such as exchangeable acidic polar compounds, cellulose and lignin, protein and pectin, and less concentrated in cell cytoplasm and nuclei. (3) Furthermore, the root cell walls were thickened when the castor seedlings exposed to CuSO4, with a large amount of high-density electron bodies, attached to the thickened cell walls. In the cell walls, most copper was bound to the carboxyl (-COOH) and hydroxyl (-OH) groups of acidic polar compounds, cellulose, hemicellulose, and polysaccharides. The conclusion showed that castor exhibited a strong tolerance to copper, the copper were accumulated mainly in the root cell, the root cell walls of castor were the major location of patience and detoxification in copper stress. PMID:25563834

  17. Influence of food on bioavailability of amdinocillin pivoxil.

    PubMed Central

    Bornemann, L D; Castellano, S; Lin, A H; Enthoven, D; Patel, I H

    1988-01-01

    The bioavailability of amdinocillin was not altered when amdinocillin pivoxil was ingested 1 h before a standard breakfast, and it increased by 20% when amdinocillin pivoxil was ingested with or 1 h after a standard breakfast. Amdinocillin pivoxil would be convenient for patients since it may be taken with or without food. PMID:3377469

  18. Characterization of Pesticide Availability/Bioavailability in Soils

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Availability/bioavailability of pesticides in soil is the integration of various processes and controls pesticide transport to water and air, exposure to and uptake by target and nontarget organisms, and degradation. Of the various processes, sorption-desorption is arguably the most important; it di...

  19. Genetic and biochemical analysis of iron bioavailability in maize

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Maize is a major cereal crop widely consumed in developing countries, which have a high prevalence of iron (Fe) deficiency including anemia. The major cause of Fe deficiency in these countries is an inadequate intake of bioavailable Fe, of which poverty is a major contributing factor. Therefore, b...

  20. Genetic and biochemical analysis of iron bioavailability in maize

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Maize is a major cereal crop widely consumed in developing countries, which have a high prevalence of iron (Fe) deficiency including anemia. The major cause of Fe deficiency in these countries is inadequate intake of bioavailable Fe, of which poverty is a major contributing factor. Therefore, biofor...

  1. DEMONSTRATION OF A BIOAVAILABLE FERRIC IRON TEST KIT

    EPA Science Inventory

    Bioavailable ferric iron (BAFeIII) is used by iron-reducing bacteria as an electron acceptor during the oxidation of various organic contaminants such as vinyl chloride and benzene. Quantification of BAFeIII is important with respect to characterizing candidate natural attenuati...

  2. Incorporating Contaminant Bioavailability into Sediment Quality Assessment Frameworks

    EPA Science Inventory

    The recently adopted sediment quality assessment framework for evaluating bay and estuarine sediments in the State of California incorporates bulk sediment chemistry as a key line of evidence(LOE) but does not address the bioavailability of measured contaminants. Thus, the chemis...

  3. Rumen microorganisms decrease bioavailability of inorganic selenium supplements

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Despite the availaility of selenium (Se)-enriched trace mineral supplements, we have observed low Se status in cattle and sheep offered traditional inorganic Se supplements. Reasons for this may include inadequate intake or low bioavailability of inorganic Se sources. The objective of this study w...

  4. Bioavailability and stability of mercury sulfide in Armuchee (USA) soil

    SciTech Connect

    Han, Fengxiang; Shiyab, Safwan; Su, Yi; Monts, David L.; Waggoner, Charles A.; Matta, Frank B.

    2007-07-01

    Because of the adverse effects of elemental mercury and mercury compounds upon human health, the U.S. Department of Energy (DOE) is engaged in an on-going effort to monitor and remediate mercury-contaminated DOE sites. In order to more cost effectively implement those extensive remediation efforts, it is necessary to obtain an improved understanding of the role that mercury and mercury compounds play in the ecosystem. We have conducted pilot scale experiments to study the bioavailability of mercury sulfide in an Armuchee (eastern US ) soil. The effects of plants and incubation time on chemical stability and bioavailability of HgS under simulated conditions of the ecosystem have been examined, as has the dynamics of the dissolution of mercury sulfide by various extractants. The results show that mercury sulfide in contaminated Armuchee soil was still to some extent bioavailable to plants. After planting, soil mercury sulfide is more easily dissolved by both 4 M and 12 M nitric acid than pure mercury sulfide reagent. Dissolution kinetics of soil mercury sulfide and pure chemical reagent by nitric acid are different. Mercury release by EDTA from HgS-contaminated soil increased with time of reaction and soil mercury level. Chelating chemicals increase the solubility and bioavailability of mercury in HgS-contaminated soil. (authors)

  5. Relative bioavailability of arsenic contaminated soils in a mouse model

    EPA Science Inventory

    Exposure to As contaminated soils compels extensive soil cleanups so that human health risks are minimized. In order to improve exposure estimates and potentially reduce remediation costs, determination of the bioavailability of As in soils is needed. The objective of this study ...

  6. Bioavailability of organoclay formulations of atrazine in soil

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pesticide formulations based on organoclays have been proposed to prolong the efficacy and reduce the environmental impact of pesticides in soil. This research addressed the question of whether organoclay-based formulations of atrazine are irreversibly sorbed or are bioavailable for bacterial degrad...

  7. [Enhancing of drug bioavailability using liquisolid system formulation].

    PubMed

    Gajdziok, Jan; Vraníková, Barbora

    2015-06-01

    One of the modern technologies of how to ensure sufficient bioavailability of drugs with limited water solubility is represented by the preparation of liquisolid systems. The functional principle of these formulations is the sorption of a drug in a liquid phase to a porous carrier (aluminometasilicates, microcrystalline cellulose, etc.). After addition of further excipients, in particular a coating material (colloidal silica), a powder is formed with the properties suitable for conversion to conventional solid unit dosage forms for oral administration (tablets, capsules). The drug is subsequently administered to the GIT already in a dissolved state, and moreover, the high surface area of the excipients and their surface hydrophilization by the solvent used, facilitates its contact with and release to the dissolution medium and GI fluids. This technology, due to its ease of preparation, represents an interesting alternative to the currently used methods of bioavailability improvement. The article follows up, by describing the specific aspects influencing the preparation of liquid systems, on the already published papers about the bioavailability of drugs and the possibilities of its technological improvement.Key words: liquisolid systems bioavailability porous carrier coating material preformulation studies. PMID:26400228

  8. Bioavailability and bioinequivalence of drug formulations in small animals.

    PubMed

    Watson, A D

    1992-06-01

    Differences in bioavailability of many drugs from their various dosage forms have been shown to be relatively common in human medicine. Although comparable bioavailability ('bioequivalence') is though to ensure comparable clinical effectiveness and safety ('therapeutic equivalence'), the relationship between bioinequivalence and therapeutic inequivalence is less clear. Thus the prevalence of clinically important differences in bioavailability is unknown. While similar concerns have arisen about drug products used in small animal practice, there have been few investigations and some earlier reports are incomplete. However, there are indications of bioinequivalence with enteral formulations of ampicillin, aspirin, chloramphenicol, digoxin, mitotane, oxytetracycline, penicillin V and theophylline. Other studies have suggested bioequivalence with enteral formulations of chloramphenicol, digoxin, phenytoin, oxytetracycline and thyroxine. Limited data for injectable preparations showed bioinequivalence with chloramphenicol and possibly oxytetracycline. There is no reason to expect formulation-related bioinequivalence to be less prevalent in veterinary than in human medicine. Indeed, it may be more common in veterinary practice because other potential influences on bioavailability (food, diseases, other drugs, etc.) are frequently ignored, and cheaper generic products are often favoured for economic reasons. PMID:1433477

  9. Relative bioavailability of soil-bound chlordecone in growing lambs.

    PubMed

    Jurjanz, S; Jondreville, C; Mahieu, M; Fournier, A; Archimède, H; Rychen, G; Feidt, C

    2014-10-01

    The pollution of soil with the pesticide chlordecone (CLD) is a problem for the use of agricultural surfaces even years after its use has been forbidden. Therefore, the exposure of free-ranged animals such as ruminants needs to be investigated in order to assess the risk of contamination of the food chain. Indeed, measured concentrations could be integrated in a lowered extent if the soil binding would reduce the bioavailability of the pesticide. This bioavailability of soil-bound CLD in a heavily polluted andosol has been investigated relatively of CLD given via spiked oil. Twenty-four weaned lambs were exposed to graded doses of 2, 4 or 6 μg CLD/kg body weight during 15 days via the contaminated soil in comparison to spiked oil. The concentration of this pesticide has been determined in two target tissues: blood serum and kidney fat. The relative bioavailability (RBA) corresponds to the slope ratio between the test matrix-contaminated soil- in comparison to the reference matrix oil. The RBA of the soil-bound CLD was not found to significantly differ from the reference matrix oil in lambs meaning that the pesticide ingested by grazing ruminants would not be sequestered by soil binding. Therefore, CLD from soil gets bioavailable within the intestinal level and exposure to contaminated soil has to be integrated in risk assessments. PMID:24729076

  10. Lead Speciation And Bioavailability In Apatite-Amended Sediments

    EPA Science Inventory

    The in situ sequestration of lead (Pb) in sediment with a phosphate amendment was investigated by Pb speciation and bioavailability. Sediment Pb in preamendment samples was identified as galena (PbS) with trace amounts of absorbed Pb. Sediment exposed to atmospheric conditions ...

  11. Speciation And Bioavailability Of Zinc In Amended Sediments

    EPA Science Inventory

    The speciation and bioavailability of zinc (Zn) in smelter-contaminated sediments was investigated as a function of phosphate (apatite) and organic amendment loading rate. Zinc species identified in preamendment sediment were zinc hydroxide-like phases, sphalerite, and zinc sorbe...

  12. ESTCP DEMONSTRATION OF A BIOAVAILABLE FERRIC IRON TEST KIT

    EPA Science Inventory

    Bioavailable ferric iron (BAFeIII) is used by iron-reducing bacteria as an electron acceptor during the oxidation of various organic contaminants such as vinyl chloride and benzene. Quantification of BAFeIII is important with respect to characterizing candidate natural attenuati...

  13. Fate and Bioavailability of Sulfamethazine in Freshwater Ecosystems

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The antibiotic sulfamethazine can be transported from manured fields to surface water bodies. We investigated the degradation, fate, and bioavailability of sulfamethazine in surface water using 14C-phenyl-sulfamethazine in small pond water microcosms. Sulfamethazine dissipated exponentially from the...

  14. Bioavailability of lead in oysters fed to young Japanese quail

    SciTech Connect

    Stone, C.L.; Spivey Fox, M.R.; Hogye, K.S.

    1981-12-01

    The presence of lead in atmospheric particulates, soil, and seawater reflects the input of both domestic and industrial wastes. Because bivalves can concentrate large quantities of heavy metals, particularly lead, consumption of their meat may be a potential risk. The relative bioavailability of lead physiologicaly incorporated into oyster meat was investigated. Day-old Japanese quail were fed purified diets with three levels of lead added as either lead acetate, freeze-dried lead-dosed oyster, or lead acetate plus freeze-dried control oyster for 2 weeks. Feeding lead from any source had little or no effect on body weight, hemoglobin, hematocrit, or percentage ash in the tibia. The concentration of lead in tibia at each level of dietary lead for each type of diet was different from those for all other levels of dietary lead. Slope-ratio analysis of the data showed that lead intrinsically incorporated into oyster meat was 69-75% as bioavailable as lead in lead acetate at levels between 25 and 100 ppm dietary lead. The combinations of (1) control oyster meat with lead acetate and (2) lead acetate with copper and zinc levels equal to those in oyster meat gave responses similar to those of the lead-dosed oyster groups. Although these data showed lower bioavailability of lead in oyster meat as compared with lead acetate, the intercept of the lines at 25 ppm dietary lead suggests that the relative bioavailability may be reserved at lower levels of lead intake.

  15. Differences in relative bioavailability of traditional Bangladeshi meal plans

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background: Iron (Fe) deficiency is the most common nutrient deficiency worldwide. Large intakes of micronutrient-poor staple crops, coupled with low intakes of highly bioavailable dietary Fe is a major cause of this deficiency. Objective: This study examined the Fe concentration and relative Fe ...

  16. Selenium bioaccessibility and bioavailability in Se-enriched food supplements.

    PubMed

    Thiry, Celine; Schneider, Yves-Jacques; Pussemier, Luc; De Temmerman, Ludwig; Ruttens, Ann

    2013-04-01

    Most European people have selenium (Se) intake inferior to recommended values that are considered necessary to ensure the beneficial action of antioxidant selenoproteins. People could therefore tend to have recourse to Se-enriched food supplements (FS) aiming to increase their Se body level. On the Belgian market, three main types of Se-rich FS are available: Se-enriched yeast, selenate-based FS, and selenite-based FS. In the present work, in vitro tests imitating gastrointestinal digestion and intestinal absorption were used to determine the bioaccessible and bioavailable fractions of Se present in one specimen of each category of FS. The aim of the study was to verify to which extent the difference in Se speciation could influence the efficiency of FS for enhancing the human Se status. Results indicated that differences exist in both bioaccessibility and bioavailability between the three types of FS, and that these differences could be related, at least partially, to the Se species profile. Overall bioavailability of the three FS was low (maximum 14 % of the original Se content). Among the three samples, the selenate-based FS produced the highest fraction of bioavailable Se, followed by Se-yeast, and finally by the selenite-based FS for which Se was almost not available at all. These results confirm the low availability of inorganic Se but were somewhat unexpected regarding the yeast-based FS since Se-rich yeasts are usually reported to contain an important fraction of available Se. PMID:23397356

  17. USE OF PELLETED LETTUCE SEEDS IN BIOAVAILABILITY STUDIES

    EPA Science Inventory

    Lettuce (Latuca sativa L., cv. Buttercrunch) is one of the most common and sensitive test organisms, among plants, used in toxicology and bioavailability studies. Much of the available lettuce seeds in commercial channels are pelleted to allow for precision machine planting. Th...

  18. Iron bioavailability of maize hemoglobin in a Caco-2 cell culture model

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Maize is an important staple crop in many parts of the world but has low iron bioavailability, in part due to its high phytate content. Hemoglobin is a form of iron that is highly bioavailable and its bioavailability is not inhibited by phytate. We hypothesize that maize hemoglobin is a highly bioav...

  19. Relative Bioavailability and Bioaccessibility and Speciation of Arsenic in Contaminated Soils

    PubMed Central

    Scheckel, Kirk G.; Nelson, Clay M.; Seales, Paul E.; Lee, Grace E.; Hughes, Michael F.; Miller, Bradley W.; Yeow, Aaron; Gilmore, Thomas; Serda, Sophia M.; Harper, Sharon; Thomas, David J.

    2011-01-01

    Background: Assessment of soil arsenic (As) bioavailability may profoundly affect the extent of remediation required at contaminated sites by improving human exposure estimates. Because small adjustments in soil As bioavailability estimates can significantly alter risk assessments and remediation goals, convenient, rapid, reliable, and inexpensive tools are needed to determine soil As bioavailability. Objectives: We evaluated inexpensive methods for assessing As bioavailability in soil as a means to improve human exposure estimates and potentially reduce remediation costs. Methods: Nine soils from residential sites affected by mining or smelting activity and two National Institute of Standards and Technology standard reference materials were evaluated for As bioavailability, bioaccessibility, and speciation. Arsenic bioavailability was determined using an in vivo mouse model, and As bioaccessibility was determined using the Solubility/Bioavailability Research Consortium in vitro assay. Arsenic speciation in soil and selected soil physicochemical properties were also evaluated to determine whether these parameters could be used as predictors of As bioavailability and bioaccessibility. Results: In the mouse assay, we compared bioavailabilities of As in soils with that for sodium arsenate. Relative bioavailabilities (RBAs) of soil As ranged from 11% to 53% (mean, 33%). In vitro soil As bioaccessibility values were strongly correlated with soil As RBAs (R2 = 0.92). Among physicochemical properties, combined concentrations of iron and aluminum accounted for 80% and 62% of the variability in estimates of RBA and bioaccessibility, respectively. Conclusion: The multifaceted approach described here yielded congruent estimates of As bioavailability and evidence of interrelations among physicochemical properties and bioavailability estimates. PMID:21749965

  20. 21 CFR 320.25 - Guidelines for the conduct of an in vivo bioavailability study.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... bioavailability study. 320.25 Section 320.25 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... Procedures for Determining the Bioavailability or Bioequivalence of Drug Products § 320.25 Guidelines for the... to a reference material. In vivo bioavailability testing of a drug product shall be in comparison...

  1. 21 CFR 320.25 - Guidelines for the conduct of an in vivo bioavailability study.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... bioavailability study. 320.25 Section 320.25 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... Procedures for Determining the Bioavailability or Bioequivalence of Drug Products § 320.25 Guidelines for the... to a reference material. In vivo bioavailability testing of a drug product shall be in comparison...

  2. 21 CFR 320.22 - Criteria for waiver of evidence of in vivo bioavailability or bioequivalence.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... bioavailability or bioequivalence. 320.22 Section 320.22 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS FOR HUMAN USE BIOAVAILABILITY AND BIOEQUIVALENCE REQUIREMENTS Procedures for Determining the Bioavailability or Bioequivalence of Drug Products §...

  3. Novel micelle formulations to increase cutaneous bioavailability of azole antifungals.

    PubMed

    Bachhav, Y G; Mondon, K; Kalia, Y N; Gurny, R; Möller, M

    2011-07-30

    Efficient topical drug administration for the treatment of superficial fungal infections would deliver the therapeutic agent to the target compartment and reduce the risk of systemic side effects. However, the physicochemical properties of the commonly used azole antifungals make their formulation a considerable challenge. The objective of the present investigation was to develop aqueous micelle solutions of clotrimazole (CLZ), econazole nitrate (ECZ) and fluconazole (FLZ) using novel amphiphilic methoxy-poly(ethylene glycol)-hexyl substituted polylactide (MPEG-hexPLA) block copolymers. The CLZ, ECZ and FLZ formulations were characterized with respect to drug loading and micelle size. The optimal drug formulation was selected for skin transport studies that were performed using full thickness porcine and human skin. Penetration pathways and micellar distribution in the skin were visualized using fluorescein loaded micelles and confocal laser scanning microscopy. The hydrodynamic diameters of the azole loaded micelles were between 70 and 165nm and the corresponding number weighted diameters (d(n)) were 30 to 40nm. Somewhat surprisingly, the lowest loading efficiency (<20%) was observed for CLZ (the most hydrophobic of the three azoles tested); in contrast, under the same conditions, ECZ was incorporated with an efficiency of 98.3% in MPEG-dihexPLA micelles. Based on the characterization data and preliminary transport experiments, ECZ loaded MPEG-dihexPLA micelles (concentration 1.3mg/mL; d(n)<40nm) were selected for further study. ECZ delivery was compared to that from Pevaryl® cream (1% w/w ECZ), a marketed liposomal formulation for topical application. ECZ deposition in porcine skin following 6h application using the MPEG-dihexPLA micelles was >13-fold higher than that from Pevaryl® cream (22.8±3.8 and 1.7±0.6μg/cm(2), respectively). A significant enhancement was also observed with human skin; the amounts of ECZ deposited were 11.3±1.6 and 1.5±0.4μg/cm(2

  4. Mercury mobility and bioavailability in soil from contaminated area

    NASA Astrophysics Data System (ADS)

    Boszke, Leonard; Kowalski, Artur; Astel, Aleksander; Barański, Andrzej; Gworek, Barbara; Siepak, Jerzy

    2008-09-01

    The mobility and bioavailability of mercury in the soil from the area near a plant using elemental mercury for manufacturing thermometers, areometers, glass energy switches and other articles made of technical glass has been evaluated. Mercury has been determined by sequential extraction method and with additional thermo desorption stage to determine elemental mercury. The procedure of sequential extraction involves five subsequent stages performed with the solutions of chloroform, deionized water, 0.5 M HCl, 0.2 M NaOH and aqua regia. The mean concentration of total mercury in soil was 147 ± 107 μg g-1 dry mass (range 62-393), and the fractionation revealed that mercury was mainly bound to sulfides 56 ± 8% (range 45-66), one of the most biounavailable and immobile species of mercury in the environment. The fractions that brought lower contribution to the total mercury content were semi-mobile humic matter 22 ± 9% (range 11-34) and elemental mercury 17 ± 5% (range 8-23). The contributions brought by the highly mobile and toxic organomercury compounds were still lower 2.3 ± 2.7% (range 0.01-6.5). The lowest contributions brought the acid-soluble mercury 1.5 ± 1.3% (range 0.1-3.5) and water-soluble mercury 1.0 ± 0.3% (range 0.6-1.7). The surface layer of soil (0-20 cm) was characterized by higher mercury concentrations than that of the subsurface soil (60-80 cm), but the fractional contributions were comparable. The comparison of mercury fractionation results obtained in this study for highly polluted soils with results of fractionation of uncontaminated or moderately contaminated samples of soil and sediments had not shown significant statistical differences; however, in the last samples elemental mercury is usually present at very low concentrations. On the basis of obtained correlation coefficients it seems that elemental mercury soils from “Areometer” plant are contaminated; the main transformation is its vaporization to atmosphere and oxidation to

  5. The concept of iron bioavailability and its assessment.

    PubMed

    Wienk, K J; Marx, J J; Beynen, A C

    1999-04-01

    In this review a broad overview of historical and current methods for the assessment of iron bioavailability was given. These methods can be divided into iron solubility studies, iron absorption studies, endpoint measures, and arithmetic models. The pros and cons of all methods were discussed. First, studies on in vitro and in vivo iron solubility have been described. The disadvantages of iron solubility include the impossibility of measuring absorption or incorporation of iron. Furthermore, only the solubility of nonheme iron, and not heme iron, can be studied. Second, we focused on iron absorption studies (either with the use of native iron, radioiron or stable iron isotopes), in which balance techniques, whole-body counting or postabsorption plasma iron measurements can be applied. In vitro determination of iron absorption using intestinal loops or cell lines, was also discussed in this part. As far as absorption studies using animals, duodenal loops, gut sacs or Caco-2 cells were concerned, the difficulty of extrapolating the results to the human situation seemed to be the major drawback. Chemical balance in man has been a good, but laborious and expensive, way to study iron absorption. Whole-body counting has the disadvantage of causing radiation exposure and it is based on a single meal. The measurement of plasma iron response did not seem to be of great value in determining nutritional iron bioavailability. The next part dealt with endpoint measures. According to the definition of iron bioavailability, these methods gave the best figure for it. In animals, the hemoglobin-repletion bioassay was most often used, whereas most studies in humans monitored the fate of radioisotopes or stable isotopes of iron in blood. Repletion bioassays using rats or other animals were of limited use because the accuracy of extrapolation to man is unknown. The use of the rat as a model for iron bioavailability seemed to be empirically based, and there were many reasons to

  6. A meta-analysis to correlate lead bioavailability and bioaccessibility and predict lead bioavailability.

    PubMed

    Dong, Zhaomin; Yan, Kaihong; Liu, Yanju; Naidu, Ravi; Duan, Luchun; Wijayawardena, Ayanka; Semple, Kirk T; Rahman, Mohammad Mahmudur

    2016-01-01

    Defining the precise clean-up goals for lead (Pb) contaminated sites requires site-specific information on relative bioavailability data (RBA). While in vivo measurement is reliable but resource insensitive, in vitro approaches promise to provide high-throughput RBA predictions. One challenge on using in vitro bioaccessibility (BAc) to predict in vivo RBA is how to minimize the heterogeneities associated with in vivo-in vitro correlations (IVIVCs) stemming from various biomarkers (kidney, blood, liver, urinary and femur), in vitro approaches and studies. In this study, 252 paired RBA-BAc data were retrieved from 9 publications, and then a Bayesian hierarchical model was implemented to address these random effects. A generic linear model (RBA (%)=(0.87±0.16)×BAc+(4.70±2.47)) of the IVIVCs was identified. While the differences of the IVIVCs among the in vitro approaches were significant, the differences among biomarkers were relatively small. The established IVIVCs were then applied to predict Pb RBA of which an overall Pb RBA estimation was 0.49±0.25. In particular the RBA in the residential land was the highest (0.58±0.19), followed by house dust (0.46±0.20) and mining/smelting soils (0.45±0.31). This is a new attempt to: firstly, use a meta-analysis to correlate Pb RBA and BAc; and secondly, estimate Pb RBA in relation to soil types. PMID:27104671

  7. Assessment of Bioavailability of Soil-Sorbed Atrazine

    PubMed Central

    Park, Jeong-Hun; Feng, Yucheng; Ji, Pingsheng; Voice, Thomas C.; Boyd, Stephen A.

    2003-01-01

    Bioavailability of pesticides sorbed to soils is an important determinant of their environmental fate and impact. Mineralization of sorbed atrazine was studied in soil and clay slurries, and a desorption-biodegradation-mineralization (DBM) model was developed to quantitatively evaluate the bioavailability of sorbed atrazine. Three atrazine-degrading bacteria that utilized atrazine as a sole N source (Pseudomonas sp. strain ADP, Agrobacterium radiobacter strain J14a, and Ralstonia sp. strain M91-3) were used in the bioavailability assays. Assays involved establishing sorption equilibrium in sterile soil slurries, inoculating the system with organisms, and measuring the CO2 production over time. Sorption and desorption isotherm analyses were performed to evaluate distribution coefficients and desorption parameters, which consisted of three desorption site fractions and desorption rate coefficients. Atrazine sorption isotherms were linear for mineral and organic soils but displayed some nonlinearity for K-saturated montmorillonite. The desorption profiles were well described by the three-site desorption model. In many instances, the mineralization of atrazine was accurately predicted by the DBM model, which accounts for the extents and rates of sorption/desorption processes and assumes biodegradation of liquid-phase, but not sorbed, atrazine. However, for the Houghton muck soil, which manifested the highest sorbed atrazine concentrations, enhanced mineralization rates, i.e., greater than those expected on the basis of aqueous-phase atrazine concentration, were observed. Even the assumption of instantaneous desorption could not account for the elevated rates. A plausible explanation for enhanced bioavailability is that bacteria access the localized regions where atrazine is sorbed and that the concentrations found support higher mineralization rates than predicted on the basis of aqueous-phase concentrations. Characteristics of high sorbed-phase concentration

  8. Bioavailability and Pharmacodynamics of Promethazine in Human Subjects

    NASA Technical Reports Server (NTRS)

    Putcha, Lakshmi; Flynn, Chris; Paloski, W. H. (Technical Monitor)

    2000-01-01

    Space Motion Sickness (SMS) is often treated in space with promethazine (PMZ). Anecdotal reports indicate that the common side effects of drowsiness and decrements in cognitive performance that are associated with PMZ administration (50 mg IM on the ground, are absent or less pronounced in space suggesting I that-the bioavailability and/or pharmacodynamic behavior of PMZ may be altered during space flight. There are limited flight opportunities available for clinical research in space, the NRA-99, therefore, solicits research required to improve, or answer specific questions about in-flight diagnosis, therapy, and post-flight rehabilitation. We propose here, to establish a noninvasive method for pharmacodynamic and therapeutic assessment of PMZ. The specific objectives of the proposed research are to, 1. Establish a saliva to plasma ratio of PMZ after administration, 2. Estimate the relative bioavailability of the three flight-specific dosage forms of PMZ, and 3. Establish the dose-response relationship of PMZ. We will estimate the bioavailability of intramuscular injection (IM), oral tablets and rectal suppositories in normal subjects during ambulatory and antiorthostatic; bed rest (ABR) conditions using novel stable isotope techniques. Drowsiness, cognitive performance and salivary flow rate will be measured as a function of circulating drug concentrations after administration of three IM doses of PMZ. We will compare and contrast the bioavailability of PMZ during normal and ABR conditions to examine whether or not ABR can simulate changes in drug, absorption and availability similar to those anticipated in a microgravity environment. Results of this study will validate methods for an approved study with this medication awaiting a flight opportunity for manifestation. These data will also provide the much needed information on the dynamics and therapeutic index. of this medication and their implications on crew fatigue and performance in space. Key words

  9. Phase behavior and oral bioavailability of amorphous Curcumin.

    PubMed

    Pawar, Yogesh B; Shete, Ganesh; Popat, Dharmesh; Bansal, Arvind K

    2012-08-30

    Amorphous form has been used as a means to improve aqueous solubility and oral bioavailability of poorly water soluble drugs. The objective of present study was to characterize thermodynamic and kinetic parameters of amorphous form of Curcumin (CRM-A). CRM-A was found to be a good glass former with glass transition temperature (T(g)) of 342.64K and critical cooling rate below 1K/min. CRM-A had a moderate tendency of crystallization and exhibited Kauzmann temperature (T(KS)) of 294.23 K. CRM-A was found to be fragile in nature as determined by T(m)/T(g) (1.32), C(p)(1 iq):C(p)(glass) (1.22), strength parameter (D<10), fragility index (m>75), T(K)/T(g) (0.85), and T(g)-T(K) (48.41). Theoretically predicted aqueous solubility advantage of 43.15-folds, was reduced to 17-folds under practical conditions. This reduction in solubility was attributed to water induced devitrification, as evident through PXRD and SEM analysis. Further, oral bioavailability study of CRM-A was undertaken to investigate bioavailability benefits, if any. C(max) was improved by 1.97-folds (statistically significant difference over control). However, oral bioavailability (AUC(0-)(∞)) was improved by 1.45-folds (statistically non significant difference over control). These observations pointed towards role of rapid devitrification of CRM-A in GIT milieu, thus limiting its oral bioavailability advantage. PMID:22609283

  10. Systems Biological Approach of Molecular Descriptors Connectivity: Optimal Descriptors for Oral Bioavailability Prediction

    PubMed Central

    Ahmed, Shiek S. S. J.; Ramakrishnan, V.

    2012-01-01

    Background Poor oral bioavailability is an important parameter accounting for the failure of the drug candidates. Approximately, 50% of developing drugs fail because of unfavorable oral bioavailability. In silico prediction of oral bioavailability (%F) based on physiochemical properties are highly needed. Although many computational models have been developed to predict oral bioavailability, their accuracy remains low with a significant number of false positives. In this study, we present an oral bioavailability model based on systems biological approach, using a machine learning algorithm coupled with an optimal discriminative set of physiochemical properties. Results The models were developed based on computationally derived 247 physicochemical descriptors from 2279 molecules, among which 969, 605 and 705 molecules were corresponds to oral bioavailability, intestinal absorption (HIA) and caco-2 permeability data set, respectively. The partial least squares discriminate analysis showed 49 descriptors of HIA and 50 descriptors of caco-2 are the major contributing descriptors in classifying into groups. Of these descriptors, 47 descriptors were commonly associated to HIA and caco-2, which suggests to play a vital role in classifying oral bioavailability. To determine the best machine learning algorithm, 21 classifiers were compared using a bioavailability data set of 969 molecules with 47 descriptors. Each molecule in the data set was represented by a set of 47 physiochemical properties with the functional relevance labeled as (+bioavailability/−bioavailability) to indicate good-bioavailability/poor-bioavailability molecules. The best-performing algorithm was the logistic algorithm. The correlation based feature selection (CFS) algorithm was implemented, which confirms that these 47 descriptors are the fundamental descriptors for oral bioavailability prediction. Conclusion The logistic algorithm with 47 selected descriptors correctly predicted the oral

  11. Water mediated alterations in gravity signal transform phytofilertation capability in hydroponic plants

    NASA Astrophysics Data System (ADS)

    Singh, Yogranjan; Singh Marabi, Rakesh; Satpute, Gyanesh Kumar; Mishra, Stuti

    2012-07-01

    signal is generated by the sedimentation of the amyloplasts. This induces a signal transduction pathway that promotes an auxin gradient across the root. The proteinogenic amino acid proline functions as a radical scavenger, electron sink, stabilizer of macromolecules, cell wall component and a metal chelation compound. In order to have most competent option for phytofilteration, the natural biodiversity out of aquatic ecosystem should be better studied. Screening of plants that produce natural chemicals whose structures are similar to the xenobiotic compounds should be the first step of any phytoremediation process. An experimental hydroponic-phytofilteration system with real effluent must give pragmatic information on the real detoxification capacity of the plants and allow determining the appropriate design and size of the future constructed wetland system to clean up the contaminated wastewater to reduce negative impact of eutrophication.

  12. Improved Oral Bioavailability Using a Solid Self-Microemulsifying Drug Delivery System Containing a Multicomponent Mixture Extracted from Salvia miltiorrhiza.

    PubMed

    Bi, Xiaolin; Liu, Xuan; Di, Liuqing; Zu, Qiang

    2016-01-01

    The active ingredients of salvia (dried root of Salvia miltiorrhiza) include both lipophilic (e.g., tanshinone IIA, tanshinone I, cryptotanshinone and dihydrotanshinone I) and hydrophilic (e.g., danshensu and salvianolic acid B) constituents. The low oral bioavailability of these constituents may limit their efficacy. A solid self-microemulsifying drug delivery system (S-SMEDDS) was developed to load the various active constituents of salvia into a single drug delivery system and improve their oral bioavailability. A prototype SMEDDS was designed using solubility studies and phase diagram construction, and characterized by self-emulsification performance, stability, morphology, droplet size, polydispersity index and zeta potential. Furthermore, the S-SMEDDS was prepared by dispersing liquid SMEDDS containing liposoluble extract into a solution containing aqueous extract and hydrophilic polymer, and then freeze-drying. In vitro release of tanshinone IIA, salvianolic acid B, cryptotanshinone and danshensu from the S-SMEDDS was examined, showing approximately 60%-80% of each active component was released from the S-SMEDDS in vitro within 20 min. In vivo bioavailability of these four constituents indicated that the S-SMEDDS showed superior in vivo oral absorption to a drug suspension after oral administration in rats. It can be concluded that the novel S-SMEDDS developed in this study increased the dissolution rate and improved the oral bioavailability of both lipophilic and hydrophilic constituents of salvia. Thus, the S-SMEDDS can be regarded as a promising new method by which to deliver salvia extract, and potentially other multicomponent drugs, by the oral route. PMID:27070565

  13. Impact of bioavailable Pb2+ on Fe2+ oxidation in the presence of a mixed culture of Acidithiobacillus ferrooxidans

    NASA Astrophysics Data System (ADS)

    Wang, H.; Yang, X.; Gong, L.; Jiang, Z.

    2009-12-01

    Numerous investigations were conducted on the effects of a variety of metals, including As, Cu, Zn, Cr on the growth of Acidithiobacillus ferrooxidans (an iron oxidizer and indigenous to acidic environment) and Fe2+ oxidation. However, less work was reported concerning the Pb2+ effect due to its quick precipitation as anglesite in SO42--rich solutions. The reported inhibiting concentrations of Pb2+ varied greatly on the oxidizing rate of ferrous in the presence of A. ferrooxidans, and the reasons remain unclear. Comparative studies were conducted between chemical and microbial oxidation of ferrous by a mixed culture of A. ferrooxidans in the presence of different concentration of Pb2+. Eh, pH and Fe2+ concentration were monitored periodically and the final precipitates were analyzed by X-ray diffraction (XRD), scanning electronic microscopy (SEM), and SEM-EDAX (Energy-dispersive X-ray spectroscopy). To check the impact of bioavailable Pb2+ on Fe2+ oxidation, initial precipitation was removed before the microbial inoculation. Our data showed that Pb2+ will exert a remarkable inhibition on microbial oxidation of ferrous when initial Pb2+ concentration reached as high as 5 g/L. However, the bioavailable Pb2+ in this case should be much lower than 5 g/L in the solution due to the precipitation of anglesite (The absolute concentration was under analysis). The threshold of Pb2+ concentrations to inhibit the microbial oxidation varies among the previous studies. This might result from the different microbial strains used or the mistaking of initial concentration as the substantial concentration of bioavailable Pb2+ after precipitation as anglesite. In contrast, Pb2+ does not show any obvious influence on chemical oxidation of ferrous. XRD spectrum of the final precipitates showed that anglesite was the only solid phase detected in chemical systems, while pure jarosite was found in the microbial systems. No lead was detected in jarosite by SEM-EDAX, inferring that Pb was

  14. Bioavailability enhancement of a poorly water-soluble drug by solid dispersion in polyethylene glycol-polysorbate 80 mixture.

    PubMed

    Joshi, Hemant N; Tejwani, Ravindra W; Davidovich, Martha; Sahasrabudhe, Vaishali P; Jemal, Mohammed; Bathala, Mohinder S; Varia, Sailesh A; Serajuddin, Abu T M

    2004-01-01

    Oral bioavailability of a poorly water-soluble drug was greatly enhanced by using its solid dispersion in a surface-active carrier. The weakly basic drug (pK(a) approximately 5.5) had the highest solubility of 0.1mg/ml at pH 1.5, < 1 microg/ml aqueous solubility between pH 3.5 and 5.5 at 24+/-1 degrees C, and no detectable solubility (< 0.02 microg/ml) at pH greater than 5.5. Two solid dispersion formulations of the drug, one in Gelucire 44/14 and another one in a mixture of polyethylene glycol 3350 (PEG 3350) with polysorbate 80, were prepared by dissolving the drug in the molten carrier (65 degrees C) and filling the melt in hard gelatin capsules. From the two solid dispersion formulations, the PEG 3350-polysorbate 80 was selected for further development. The oral bioavailability of this formulation in dogs was compared with that of a capsule containing micronized drug blended with lactose and microcrystalline cellulose and a liquid solution in a mixture of PEG 400, polysorbate 80 and water. For intravenous administration, a solution in a mixture of propylene glycol, polysorbate 80 and water was used. Absolute oral bioavailability values from the capsule containing micronized drug, the capsule containing solid dispersion and the oral liquid were 1.7+/-1.0%, 35.8+/-5.2% and 59.6+/-21.4%, respectively. Thus, the solid dispersion provided a 21-fold increase in bioavailability of the drug as compared to the capsule containing micronized drug. A capsule formulation containing 25 mg of drug with a total fill weight of 600 mg was subsequently selected for further development. The selected solid dispersion formulation was physically and chemically stable under accelerated storage conditions for at least 6 months. It is hypothesized that polysorbate 80 ensures complete release of drug in a metastable finely dispersed state having a large surface area, which facilitates further solubilization by bile acids in the GI tract and the absorption into the enterocytes. Thus, the

  15. A Case Study of Indoor Garden-Based Learning with Hydroponics and Aquaponics: Evaluating Pro-Environmental Knowledge, Perception, and Behavior Change

    ERIC Educational Resources Information Center

    Jon Schneller, Andrew; Schofield, Casey A.; Frank, Jenna; Hollister, Eliza; Mamuszka, Lauren

    2015-01-01

    This article reports on a mixed methods evaluation of an indoor garden-based learning curriculum for 5th and 6th graders which incorporated aquaponics and hydroponics technologies. This study provides a better understanding of the extent to which indoor gardening technologies can be used within the formal curriculum as an effective teaching tool.…

  16. Dynamics, chemical properties and bioavailability of DOC in an early successional catchment

    NASA Astrophysics Data System (ADS)

    Risse-Buhl, U.; Hagedorn, F.; Dümig, A.; Gessner, M. O.; Schaaf, W.; Nii-Annang, S.; Gerull, L.; Mutz, M.

    2013-01-01

    The dynamics of dissolved organic carbon (DOC) have been intensively studied in mature ecosystems, but little is known about DOC dynamics and the significance of DOC as a substrate for microbial activity in early-successional catchments. We determined the concentration, chemical composition, source, radiocarbon age, and bioavailability of DOC along the hydrological flow path from soil solution to a downstream pond in a recently constructed catchment (Chicken Creek Catchment, Germany). Soil solution, upwelling ground water, subsurface water in an alluvial fan, and pond water all had high DOC concentrations (averages of 6.0-11.6 mg DOC L-1), despite small carbon stocks in either vegetation or soil of the early-successional catchment. The mean 14C age of DOC in upwelling ground water was 2600 to 2800 yr. Solid-state CPMAS 13C NMR revealed a higher proportion of aromatic compounds (32%) and a lower proportion of carbohydrates (33%) in upwelling ground water than in pond water (18% and 45%, respectively). The 14C age and 13C NMR spectra suggest that DOC was partly mobilized from charred organic matter of the Quaternary substrate. In an experimental 70-days incubation experiment, 20% of the total DOC was found to be bioavailable, irrespective of the water type. Origin of microbial communities (enriched from soil, stream sediment or pond water) had only marginal effects on overall DOC utilization. Overall, these data suggest that the old DOC can support microbial activity during early ecosystem succession to some extent, although the largest fraction is recalcitrant DOC that is exported from the catchment once it has been mobilized.

  17. Dynamics, chemical properties and bioavailability of DOC in an early successional catchment

    NASA Astrophysics Data System (ADS)

    Risse-Buhl, U.; Hagedorn, F.; Dümig, A.; Gessner, M. O.; Schaaf, W.; Nii-Annang, S.; Gerull, L.; Mutz, M.

    2013-07-01

    The dynamics of dissolved organic carbon (DOC) have been intensively studied in mature ecosystems, but little is known about DOC dynamics and the significance of DOC as a substrate for microbial activity in early-successional catchments. We determined the concentration, chemical composition, source, radiocarbon age, and bioavailability of DOC along the hydrological flow path from soil solution to a downstream pond in a recently constructed catchment (Chicken Creek Catchment, Germany). Soil solution, upwelling ground water, stream water, subsurface water in an alluvial fan, and pond water all had high DOC concentrations (averages: 6.0-11.6 mg DOC L-1), despite small carbon stocks in both vegetation and soil of the catchment. Solid-state CPMAS 13C NMR of DOC in upwelling ground water revealed a higher proportion of aromatic compounds (32%) and a lower proportion of carbohydrates (33%) than in pond water (18% and 45%, respectively). The average 14C age of DOC in upwelling ground water was 2600 to 2900 yr, while organic matter of the Quaternary substrate of the catchment had a 14C age of 3000 to 16 000 yr. Both the 14C age data and 13C NMR spectra suggest that DOC partly derived from organic matter of the Quaternary substrate (about 40 to 90% of the C in the DOC), indicating that both recent and old C of the DOC can support microbial activity during early ecosystem succession. However, in a 70 day incubation experiment, only about 11% of the total DOC was found to be bioavailable. This proportion was irrespective of the water type. Origin of the microbial communities within the catchment (enriched from soil, stream sediment or pond water) also had only a marginal effect on overall DOC utilization.

  18. A structural equation model of soil metal bioavailability to earthworms: confronting causal theory and observations using a laboratory exposure to field-contaminated soils.

    PubMed

    Beaumelle, Léa; Vile, Denis; Lamy, Isabelle; Vandenbulcke, Franck; Gimbert, Frédéric; Hedde, Mickaël

    2016-11-01

    Structural equation models (SEM) are increasingly used in ecology as multivariate analysis that can represent theoretical variables and address complex sets of hypotheses. Here we demonstrate the interest of SEM in ecotoxicology, more precisely to test the three-step concept of metal bioavailability to earthworms. The SEM modeled the three-step causal chain between environmental availability, environmental bioavailability and toxicological bioavailability. In the model, each step is an unmeasured (latent) variable reflected by several observed variables. In an exposure experiment designed specifically to test this SEM for Cd, Pb and Zn, Aporrectodea caliginosa was exposed to 31 agricultural field-contaminated soils. Chemical and biological measurements used included CaC12-extractable metal concentrations in soils, free ion concentration in soil solution as predicted by a geochemical model, dissolved metal concentration as predicted by a semi-mechanistic model, internal metal concentrations in total earthworms and in subcellular fractions, and several biomarkers. The observations verified the causal definition of Cd and Pb bioavailability in the SEM, but not for Zn. Several indicators consistently reflected the hypothetical causal definition and could thus be pertinent measurements of Cd and Pb bioavailability to earthworm in field-contaminated soils. SEM highlights that the metals present in the soil solution and easily extractable are not the main source of available metals for earthworms. This study further highlights SEM as a powerful tool that can handle natural ecosystem complexity, thus participating to the paradigm change in ecotoxicology from a bottom-up to a top-down approach. PMID:27378153

  19. Overview on gastroretentive drug delivery systems for improving drug bioavailability.

    PubMed

    Lopes, Carla M; Bettencourt, Catarina; Rossi, Alessandra; Buttini, Francesca; Barata, Pedro

    2016-08-20

    In recent decades, many efforts have been made in order to improve drug bioavailability after oral administration. Gastroretentive drug delivery systems are a good example; they emerged to enhance the bioavailability and effectiveness of drugs with a narrow absorption window in the upper gastrointestinal tract and/or to promote local activity in the stomach and duodenum. Several strategies are used to increase the gastric residence time, namely bioadhesive or mucoadhesive systems, expandable systems, high-density systems, floating systems, superporous hydrogels and magnetic systems. The present review highlights some of the drugs that can benefit from gastroretentive strategies, such as the factors that influence gastric retention time and the mechanism of action of gastroretentive systems, as well as their classification into single and multiple unit systems. PMID:27173823

  20. Declining bioavailability and inappropriate estimation of risk of persistent compounds

    SciTech Connect

    Kelsey, J.W.; Alexander, M.

    1997-03-01

    Earthworms (Eisenia foetida) assimilated decreasing amounts of atrazine, phenanthrene, and naphthalene that had been incubated for increasing periods of time in sterile soil. The amount of atrazine and phenanthrene removed from soil by mild extractants also decreased with time. The declines in bioavailability of the three compounds to earthworms and of naphthalene to bacteria were not reflected by analysis involving vigorous methods of solvent extraction; similar results for bioavailability of phenanthrene and 4-nitrophenol to bacteria were obtained in a previous study conducted at this laboratory. The authors suggest that regulations based on vigorous extractions for the analyses of persistent organic pollutants in soil do not appropriately estimate exposure or risk to susceptible populations.

  1. Bioavailability of capsaicin and its implications for drug delivery

    PubMed Central

    Rollyson, William D.; Stover, Cody A.; Brown, Kathleen C.; Perry, Haley E.; Stevenson, Cathryn D.; McNees, Christopher A.; Ball, John G.; Valentovic, Monica A.; Dasgupta, Piyali

    2014-01-01

    The dietary compound capsaicin is responsible for the “hot and spicy” taste of chili peppers and pepper extracts. It is a valuable pharmacological agent with several therapeutic applications in controlling pain and inflammation. Emerging studies show that it displays potent anti-tumor activity in several human cancers. On a more basic research level, capsaicin has been used as a ligand to activate several types of ion-channel receptors. The pharmacological activity of capsaicin-like compounds is dependent on several factors like the dose, the route of administration and most importantly on its concentration at target tissues. The present review describes the current knowledge involving the metabolism and bioavailability of capsaicinoids in rodents and humans. Novel drug delivery strategies used to improve the bioavailability and therapeutic index of capsaicin are discussed in detail. The generation of novel capsaicin-mimetics and improved drug delivery methods will foster the hope of innovative applications of capsaicin in human disease. PMID:25307998

  2. Bioavailability of capsaicin and its implications for drug delivery.

    PubMed

    Rollyson, William D; Stover, Cody A; Brown, Kathleen C; Perry, Haley E; Stevenson, Cathryn D; McNees, Christopher A; Ball, John G; Valentovic, Monica A; Dasgupta, Piyali

    2014-12-28

    The dietary compound capsaicin is responsible for the "hot and spicy" taste of chili peppers and pepper extracts. It is a valuable pharmacological agent with several therapeutic applications in controlling pain and inflammation. Emerging studies show that it displays potent anti-tumor activity in several human cancers. On a more basic research level, capsaicin has been used as a ligand to activate several types of ion-channel receptors. The pharmacological activity of capsaicin-like compounds is dependent on several factors like the dose, the route of administration and most importantly on its concentration at target tissues. The present review describes the current knowledge involving the metabolism and bioavailability of capsaicinoids in rodents and humans. Novel drug delivery strategies used to improve the bioavailability and therapeutic index of capsaicin are discussed in detail. The generation of novel capsaicin-mimetics and improved drug delivery methods will foster the hope of innovative applications of capsaicin in human disease. PMID:25307998

  3. Acetylated Hyaluronic Acid: Enhanced Bioavailability and Biological Studies

    PubMed Central

    Saturnino, Carmela; Sinicropi, Maria Stefania; Puoci, Francesco

    2014-01-01

    Hyaluronic acid (HA), a macropolysaccharidic component of the extracellular matrix, is common to most species and it is found in many sites of the human body, including skin and soft tissue. Not only does HA play a variety of roles in physiologic and in pathologic events, but it also has been extensively employed in cosmetic and skin-care products as drug delivery agent or for several biomedical applications. The most important limitations of HA are due to its short half-life and quick degradation in vivo and its consequently poor bioavailability. In the aim to overcome these difficulties, HA is generally subjected to several chemical changes. In this paper we obtained an acetylated form of HA with increased bioavailability with respect to the HA free form. Furthermore, an improved radical scavenging and anti-inflammatory activity has been evidenced, respectively, on ABTS radical cation and murine monocyte/macrophage cell lines (J774.A1). PMID:25114930

  4. Intestinal transport as a potential determinant of drug bioavailability.

    PubMed

    Nauli, Andromeda M; Nauli, Surya M

    2013-08-01

    Orally administered drugs are generally absorbed by the small intestine and transported either to the lymphatic system or to the hepatic portal system. In general, lipid soluble drugs and vitamins are transported by the small intestine to the lymphatics, and water-soluble drugs are transported to the hepatic portal system. By avoiding the early hepatic first pass effect, the lymphatic transport system may increase drug bioavailability. In addition to its transport systems, the small intestine may affect drug bioavailability through drug uptake, intestinal first pass effect, recruitment of drugs by chylomicrons, formation and secretion of chylomicrons, and enterohepatic circulation. All of these factors should be considered when formulating orally administered lipophilic drugs. Our data also suggest that Caco-2 cells may serve as a valuable in vitro model to study the intestinal transport of orally administered drugs. PMID:23343017

  5. Butanol extraction to predict bioavailability of PAHs in soil.

    PubMed

    Liste, Hans-Holger; Alexander, Martin

    2002-02-01

    The feasibility of a mild-solvent extraction procedure to predict the bioavailability of individual polycyclic aromatic hydrocarbons (PAHs) in soil was assessed. The quantities that were degraded during the course of biodegradation of phenanthrene and pyrene in soil with or without plants correlated with the amounts extracted by n-butanol, with R2 values of 0.971 and 0.994, respectively. Six consecutive groups of earthworms removed ca. 70% of the pyrene remaining after extensive biodegradation, a value similar to the quantity extracted by n-butanol. The amount of chrysene aged in sterilized soil that was extracted by n-butanol was not statistically different from the quantities assimilated by earth-worms (Eisenia fetida) introduced into the soil. Such a mild extraction procedure may be useful as a means of predicting PAH bioavailability. PMID:11999764

  6. Bioavailability of Glucosinolates and Their Breakdown Products: Impact of Processing.

    PubMed

    Barba, Francisco J; Nikmaram, Nooshin; Roohinejad, Shahin; Khelfa, Anissa; Zhu, Zhenzhou; Koubaa, Mohamed

    2016-01-01

    Glucosinolates are a large group of plant secondary metabolites with nutritional effects, and are mainly found in cruciferous plants. After ingestion, glucosinolates could be partially absorbed in their intact form through the gastrointestinal mucosa. However, the largest fraction is metabolized in the gut lumen. When cruciferous are consumed without processing, myrosinase enzyme present in these plants hydrolyzes the glucosinolates in the proximal part of the gastrointestinal tract to various metabolites, such as isothiocyanates, nitriles, oxazolidine-2-thiones, and indole-3-carbinols. When cruciferous are cooked before consumption, myrosinase is inactivated and glucosinolates transit to the colon where they are hydrolyzed by the intestinal microbiota. Numerous factors, such as storage time, temperature, and atmosphere packaging, along with inactivation processes of myrosinase are influencing the bioavailability of glucosinolates and their breakdown products. This review paper summarizes the assimilation, absorption, and elimination of these molecules, as well as the impact of processing on their bioavailability. PMID:27579302

  7. Bioavailability of Glucosinolates and Their Breakdown Products: Impact of Processing

    PubMed Central

    Barba, Francisco J.; Nikmaram, Nooshin; Roohinejad, Shahin; Khelfa, Anissa; Zhu, Zhenzhou; Koubaa, Mohamed

    2016-01-01

    Glucosinolates are a large group of plant secondary metabolites with nutritional effects, and are mainly found in cruciferous plants. After ingestion, glucosinolates could be partially absorbed in their intact form through the gastrointestinal mucosa. However, the largest fraction is metabolized in the gut lumen. When cruciferous are consumed without processing, myrosinase enzyme present in these plants hydrolyzes the glucosinolates in the proximal part of the gastrointestinal tract to various metabolites, such as isothiocyanates, nitriles, oxazolidine-2-thiones, and indole-3-carbinols. When cruciferous are cooked before consumption, myrosinase is inactivated and glucosinolates transit to the colon where they are hydrolyzed by the intestinal microbiota. Numerous factors, such as storage time, temperature, and atmosphere packaging, along with inactivation processes of myrosinase are influencing the bioavailability of glucosinolates and their breakdown products. This review paper summarizes the assimilation, absorption, and elimination of these molecules, as well as the impact of processing on their bioavailability. PMID:27579302

  8. Increased acyclovir oral bioavailability via a bile acid conjugate.

    PubMed

    Tolle-Sander, Sanna; Lentz, Kimberley A; Maeda, Dean Y; Coop, Andrew; Polli, James E

    2004-01-12

    The objective of this work was to design an acyclovir prodrug that would utilize the human apical sodium-dependent bile acid transporter (hASBT) and enhance acyclovir oral bioavailability. Using each chenodeoxycholate, deoxycholate, cholate, and ursodeoxycholate, four bile acid prodrugs of acyclovir were synthesized, where acyclovir was conjugated to a bile acid via a valine linker. The affinity of the prodrug for hASBT was determined through inhibition of taurocholate uptake by COS-7 cells transfected with hASBT (hASBT-COS). The prodrug with the highest inhibitory affinity was further evaluated in vitro and in vivo. The prodrug acyclovir valylchenodeoxycholate yielded the highest affinity for hASBT (Ki = 35 microM), showing that chenodeoxycholate is the free bile acid with the greatest affinity for hASBT. Acyclovir valylchenodeoxycholate's affinity was similar to that of cholic acid (Ki = 25 microM). Further characterization showed that acyclovir was catalytically liberated from acyclovir valylchenode-oxycholate by esterase. Relative to cellular uptake studies of acyclovir alone, the cellular uptake from the prodrug resulted in a 16-fold greater acyclovir accumulation within hASBT-COS cells, indicating enhanced permeation properties of the prodrug. Enhanced permeability was due to hASBT-mediated uptake and increased passive permeability. The extent of acyclovir uptake in the presence of sodium was 1.4-fold greater than the extent of passive prodrug uptake in the absence of sodium (p = 0.02), indicating translocation of the prodrug by hASBT. The prodrug also exhibited an almost 12-fold enhanced passive permeability, relative to acyclovir's passive permeability. Oral administration of acyclovir valylchenodeoxycholate to rats resulted in a 2-fold increase in the bioavailability of acyclovir, compared to the bioavailability after administration of acyclovir alone. Results indicate that a bile acid prodrug strategy may be useful in improving the oral bioavailability of

  9. Lycopene bioavailability is associated with a combination of genetic variants.

    PubMed

    Borel, Patrick; Desmarchelier, Charles; Nowicki, Marion; Bott, Romain

    2015-06-01

    The intake of tomatoes and tomato products, which constitute the main dietary source of the red pigment lycopene (LYC), has been associated with a reduced risk of prostate cancer and cardiovascular disease, suggesting a protective role of this carotenoid. However, LYC bioavailability displays high interindividual variability. This variability may lead to varying biological effects following LYC consumption. Based on recent results obtained with two other carotenoids, we assumed that this variability was due, at least in part, to several single nucleotide polymorphisms (SNPs) in genes involved in LYC and lipid metabolism. Thus, we aimed at identifying a combination of SNPs significantly associated with the variability in LYC bioavailability. In a postprandial study, 33 healthy male volunteers consumed a test meal containing 100g tomato puree, which provided 9.7 mg all-trans LYC. LYC concentrations were measured in plasma chylomicrons (CM) isolated at regular time intervals over 8 h postprandially. For the study 1885 SNPs in 49 candidate genes, i.e., genes assumed to play a role in LYC bioavailability, were selected. Multivariate statistical analysis (partial least squares regression) was used to identify and validate the combination of SNPs most closely associated with postprandial CM LYC response. The postprandial CM LYC response to the meal was notably variable with a CV of 70%. A significant (P=0.037) and validated partial least squares regression model, which included 28 SNPs in 16 genes, explained 72% of the variance in the postprandial CM LYC response. The postprandial CM LYC response was also positively correlated to fasting plasma LYC concentrations (r=0.37, P<0.05). The ability to respond to LYC is explained, at least partly, by a combination of 28 SNPs in 16 genes. Interindividual variability in bioavailability apparently affects the long-term blood LYC status, which could ultimately modulate the biological response following LYC supplementation. PMID

  10. Rumen Microorganisms Decrease Bioavailability of Inorganic Selenium Supplements.

    PubMed

    Galbraith, M L; Vorachek, W R; Estill, C T; Whanger, P D; Bobe, G; Davis, T Z; Hall, J A

    2016-06-01

    Despite the availability of selenium (Se)-enriched trace mineral supplements, we have observed low Se status in cattle and sheep offered traditional inorganic Se supplements. Reasons for this may include inadequate intake or low bioavailability of inorganic Se sources. The objective of this study was to determine whether rumen microorganisms (RMO) alter the bioavailability of Se sources commonly used in Se supplements. Rumen microorganisms were isolated from ewes (n = 4) and incubated ex vivo with no Se (control), with inorganic Na selenite or Na selenate, or with organic selenomethionine (SeMet). Total Se incorporated into RMO and the amount of elemental Se formed were determined under equivalent conditions. Incorporation of Se from Na selenite, Na selenate, or SeMet into RMO was measured as fold change compared with control (no added Se). Incorporation of Se into microbial mass was greater for SeMet (13.2-fold greater than no-Se control) compared with inorganic Se supplements (P = 0.02); no differences were observed between inorganic Na selenate (3.3-fold greater than no-Se control) and Na selenite (3.5-fold greater than no-Se control; P = 0.97). Formation of non-bioavailable, elemental Se was less for RMO incubated with SeMet compared with inorganic Se sources (P = 0.01); no differences were observed between Na selenate and Na selenite (P = 0.09). The clinical importance of these results is that the oral bioavailability of organic SeMet should be greater compared with inorganic Se sources because of greater RMO incorporation of Se and decreased formation of elemental Se by RMO. PMID:26537117

  11. Enhanced bioavailability of atorvastatin calcium from stabilized gastric resident formulation.

    PubMed

    Khan, Furquan Nazimuddin; Dehghan, Mohamed Hassan G

    2011-12-01

    Oral bioavailability of atorvastatin calcium (ATC) is very low (only 14%) due to instability and incomplete intestinal absorption and/or extensive gut wall extraction. When ATC is packed in the form of tablets, powders, etc., it gets destabilized as it is exposed to the oxidative environment, which is usually present during the production process, the storage of the substance, and the pharmaceutical formulation. Therefore, stabilized gastro-retentive floating tablets of ATC were prepared to enhance bioavailability. Water sorption and viscosity measurement studies are performed to get the best polymer matrix for gastro-retention. A 3(2) factorial design used to prepare optimized formulation of ATC. The selected excipients such as docusate sodium enhanced the stability and solubility of ATC in gastric media and tablet dosage form. The best formulation (F4) consisting of hypromellose, sodium bicarbonate, polyethylene oxide, docusate sodium, mannitol, crosscarmellose sodium, and magnesium stearate, gave floating lag time of 56 ± 4.16 s and good matrix integrity with in vitro dissolution of 98.2% in 12 h. After stability studies, no significant change was observed in stability, solubility, floating lag time, total floating duration, matrix integrity, and sustained drug release rates, as confirmed by DSC and powder X-ray diffraction studies. In vivo pharmacokinetic study performed in rabbits revealed enhanced bioavailability of F4 floating tablets, about 1.6 times compared with that of the conventional tablet (Storvas® 80 mg tablet). These results suggest that the gastric resident formulation is a promising approach for the oral delivery of ATC for improving bioavailability. PMID:21879394

  12. Glycosyl glycerides from hydroponic Panax ginseng inhibited NO production in lipopolysaccharide-stimulated RAW264.7 cells

    PubMed Central

    Cha, Byeong-Ju; Park, Ji-Hae; Shrestha, Sabina; Baek, Nam-In; Lee, Sang Min; Lee, Tae Hoon; Kim, Jiyoung; Kim, Geum-Soog; Kim, Seung-Yu; Lee, Dae-Young

    2014-01-01

    Background Although the aerial parts of hydroponic Panax ginseng are reported to contain higher contents of total ginsenosides than those of roots, the isolation and identification of active metabolites from the aerial parts of hydroponic P. ginseng have not been carried out so far. Methods The aerial parts of hydroponic P. ginseng were applied on repeated silica gel and octadecylsilane columns to yield four glycosyl glycerides (Compounds 1–4), which were identified based on nuclear magnetic resonance, infrared, fast atom bombardment mass spectrometry, and gas chromatography/mass spectrometry data. Compounds 1–4 were evaluated for inhibition activity on NO production in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. Results and conclusion The glycosyl glycerides were identified to be (2S)-1-O-7(Z),10(Z),13(Z)-hexadecatrienoyl-3-O-β-d-galactopyranosyl-sn-glycerol (1), (2S)-1-O-linolenoyl-3-O-β-d-galactopyranosyl-sn-glycerol (2), (2S)-1-O-linolenoyl-2-O-linolenoyl-3-O-β-d-galactopyranosyl-sn-glycerol (3), and 2(S)-1-O-linoleoyl-2-O-linoleoyl-3-O-β-d-galactopyranosyl-sn-glycerol (4). Compounds 1 and 2 showed moderate inhibition activity on NO production in LPS-stimulated RAW264.7 cells [half maximal inhibitory concentration (IC50): 63.8 ± 6.4μM and 59.4 ± 6.8μM, respectively] without cytotoxicity at concentrations < 100μM, whereas Compounds 3 and 4 showed good inhibition effect (IC50: 7.7 ± 0.6μM and 8.0 ± 0.9μM, respectively) without cytotoxicity at concentrations < 20μM. All isolated compounds showed reduced messenger RNA (mRNA) expression of interleukin-1β (IL-1β), IL-6, and tumor necrosis factor-α in LPS-induced macrophage cells with strong inhibition of mRNA activity observed for Compounds 3 and 4. PMID:26045690

  13. Effects of phosphate and thiosulphate on arsenic accumulation in Brassica juncea plants grown in soil and in hydroponic culture

    NASA Astrophysics Data System (ADS)

    Pezzarossa, Beatrice; Petruzzelli, Gianniantonio; Grifoni, Martina; Rosellini, Irene; Malagoli, Mario; Schiavon, Michela

    2013-04-01

    Arsenic is recognised as a toxic metalloid and a strong pollutant in soils of many countries. Thus, the reclamation of contaminated areas is fundamental in order to protect both human health and agricultural production. This study is focused on the assisted phytoextraction, a technology for reclaiming polluted soils that takes advantage of the capability of some plants to extract inorganic elements from soils with the aid of additive agents. The nutrients phosphorus, as phosphate, and sulphur, as thiosulphate, can compete with the form more oxidised of arsenic, both in soil and plant. This study examined the capability of thiosulphate (Th) and phosphate (Ph) to promote the release of As from soil surfaces in order to improve the phytoavailability and thus the absorption of As by Brassica juncea plants. In the first experiment B. juncea plants were grown on a soil that had been sampled from an industrial area strongly contaminated by As (790 mg As kg-1 soil). The second experiment was carried out in hydroponics where As has been added at a concentration (100 microM) similar to the As available concentration measured in soil. In both trials ammonium thiosulphate (at the concentration of 0.27 M in soil, and 400 microM in hydroponics) and potassium hydrogen phosphate (at the concentration of 0.05 M in soil, and 112 microM in hydroponics) were added. The biomass of B. juncea was determined and the accumulation of P, S and As in root and in the above-ground tissues have been analyzed. Our results showed that thiosulphate and phosphate acted either as nutrients and detoxifying agents, due to the stimulation of plant defensive systems, and influenced either the biomass production and the As accumulation in plant tissues. In the plants grown in soil, As accumulated at higher levels in the above-ground part than in the roots and the addition of Th induced a higher biomass production and a higher total As accumulation (concentration x biomass) in the above-ground tissues

  14. Estimation of bioavailability of metals from drilling mud barite.

    PubMed

    Neff, Jerry M

    2008-04-01

    Drilling mud and associated drill cuttings are the largest volume wastes associated with drilling of oil and gas wells and often are discharged to the ocean from offshore drilling platforms. Barite (BaSO4) often is added as a weighting agent to drilling muds to counteract pressure in the geologic formations being drilled, preventing a blowout. Some commercial drilling mud barites contain elevated (compared to marine sediments) concentrations of several metals. The metals, if bioavailable, may harm the local marine ecosystem. The bioavailable fraction of metals is the fraction that dissolves from the nearly insoluble, solid barite into seawater or sediment porewater. Barite-seawater and barite-porewater distribution coefficients (Kd) were calculated for determining the predicted environmental concentration (PEC; the bioavailable fraction) of metals from drilling mud barite in the water column and sediments, respectively. Values for Kdbarite-seawater and Kdbarite-porewater were calculated for barium, cadmium, chromium, copper, mercury, lead, and zinc in different grades of barite. Log Kdbarite-seawater values were higher (solubility was lower) for metals in the produced water plume than log Kdbarite-porewater values for metals in sediments. The most soluble metals were cadmium and zinc and the least soluble were mercury and copper. Log Kd values can be used with data on concentrations of metals in barite and of barite in the drilling mud-cuttings plume and in bottom sediments to calculate PECseawater and PECsediment. PMID:17994916

  15. Selenium bioavailability: current knowledge and future research requirements.

    PubMed

    Fairweather-Tait, Susan J; Collings, Rachel; Hurst, Rachel

    2010-05-01

    Information on selenium bioavailability is required to derive dietary recommendations and to evaluate and improve the quality of food products. The need for robust data is particularly important in light of recent suggestions of potential health benefits associated with different intakes of selenium. The issue is not straightforward, however, because of large variations in the selenium content of foods (determined by a combination of geologic/environmental factors and selenium supplementation of fertilizers and animal feedstuffs) and the chemical forms of the element, which are absorbed and metabolized differently. Although most dietary selenium is absorbed efficiently, the retention of organic forms is higher than that of inorganic forms. There are also complications in the assessment and quantification of selenium species within foodstuffs. Often, extraction is only partial, and the process can alter the form or forms present in the food. Efforts to improve, standardize, and make more widely available techniques for species quantification are required. Similarly, reliable and sensitive functional biomarkers of selenium status are required, together with improvements in current biomarker methods. This requirement is particularly important for the assessment of bioavailability, because some functional biomarkers respond differently to the various selenium species. The effect of genotype adds a potential further dimension to the process of deriving bioavailability estimates and underlines the need for further research to facilitate the process of deriving dietary recommendations in the future. PMID:20200264

  16. Bioavailability of zinc in runoff water from roofing materials.

    PubMed

    Heijerick, D G; Janssen, C R; Karlèn, C; Wallinder, I Odnevall; Leygraf, C

    2002-06-01

    Corrosion and runoff from zinc-coated materials and outdoor structures is an important source for the dispersion of zinc in the environment. Being part of a large inter-disciplinary research project, this study presents the bioavailability of zinc in runoff water immediately after release from the surface of 15 different commercially available zinc-based materials exposed to the urban environment of Stockholm, Sweden. Runoff water was analysed chemically and evaluated for its possible environmental impact, using both a biosensor test with the bacteria Alcaligenes eutrophus (Biomet) and the conventional 72 h growth inhibition test with the green alga Raphidocelis subcapitata. Chemical speciation modelling revealed that most zinc (94.3-99.9%) was present as the free Zn ion, the most bioavailable speciation form. These findings were confirmed by the results of the biosensor test (Biomet) which indicated that all zinc was indeed bioavailable. Analysis of the ecotoxicity data also suggested that the observed toxic effects were due to the presence of Zn2+ ions. Finally, regression analysis showed that, for this type of runoff samples, the rapid screening biosensor was capable of predicting (a) the total amount of zinc present in the runoff samples (R2 of 0.93-0.98; p < 0.05) and (b) the observed 72 h-EbC50s (R2 of 0.69-0.97; p < 0.05). PMID:12137040

  17. Bioavailability of polycyclic aromatic hydrocarbons in the North Sea

    SciTech Connect

    Utvik, T.I.R. . Environmental Section); Johnsen, S. )

    1999-06-15

    Semipermeable membrane devices (SPMDs) and blue mussels (Mytilus edulis) were used to determine the bioavailable fraction of polycyclic aromatic hydrocarbons (PAHs) from oil field produced water in the North Sea. The SPMDs and mussels were deployed at 5, 10, and 50 m depth; 100 and 300 m downstream the discharge point; and at a reference site 16 km away. In both SPMDs and mussels, the concentration of PAHs increased significantly toward the discharge point, with the strongest contribution from the lower molecular weight compounds (naphthalene, phenanthrene, dibenzothiophene, and their C1-C3 alkyl homologues). The relative increase in PAH concentration from the reference site to the site at 100 m was higher for mussels than for the SPMDs. The SPMDs reflect the water-soluble fraction of the PAHs, which is probably the most important route of exposure for organisms at lower trophic levels and presumably also the fraction available for uptake by a respiratory route. Residues in the mussels represent both the water-soluble and particle-bound fraction and give information about bioavailability of the PAHs for organisms at higher trophic levels. The results of this study suggest that both techniques give important information about the bioavailability of PAHs to marine organisms.

  18. Bioavailability and Pharmacokinetics of Genistein: Mechanistic Studies on its ADME

    PubMed Central

    Yang, Zhen; Kulkarni, Kaustubh; Zhu, Wei; Hu, Ming

    2014-01-01

    Genistein, one of the most active natural flavonoids, exerts various biological effects including chemoprevention, antioxidation, antiproliferation and anticancer. More than 30 clinical trials of genistein with various disease indications have been conducted to evaluate its clinical efficacy. Based on many animals and human pharmacokinetic studies, it is well known that the most challenge issue for developing genistein as a chemoprevention agent is the low oral bioavailability, which may be the major reason relating to its ambiguous therapeutic effects and large interindividual variations in clinical trials. In order to better correlate pharmacokinetic to pharmacodynamics results in animals and clinical studies, an in-depth understanding of pharmacokinetic behavior of genistein and its ADME properties are needed. Numerous in vitro/in vivo ADME studies had been conducted to reveal the main factors contributing to the low oral bioavailability of genistein. Therefore, this review focuses on summarizing the most recent progress on mechanistic studies of genistein ADME and provides a systemic view of these processes to explain genistein pharmacokinetic behaviors in vivo. The better understanding of genistein ADME property may lead to development of proper strategy to improve genistein oral bioavailability via mechanism-based approaches. PMID:22583407

  19. Accounting for differences in the bioactivity and bioavailability of vitamers

    PubMed Central

    Gregory, Jesse F.

    2012-01-01

    Essentially all vitamins exist with multiple nutritionally active chemical species often called vitamers. Our quantitative understanding of the bioactivity and bioavailability of the various members of each vitamin family has increased markedly, but many issues remain to be resolved concerning the reporting and use of analytical data. Modern methods of vitamin analysis rely heavily on chromatographic techniques that generally allow the measurement of the individual chemical forms of vitamins. Typical applications of food analysis include the evaluation of shelf life and storage stability, monitoring of nutrient retention during food processing, developing food composition databases and data needed for food labeling, assessing dietary adequacy and evaluating epidemiological relationships between diet and disease. Although the usage of analytical data varies depending on the situation, important issues regarding how best to present and interpret the data in light of the presence of multiple vitamers are common to all aspects of food analysis. In this review, we will evaluate the existence of vitamers that exhibit differences in bioactivity or bioavailability, consider when there is a need to address differences in bioactivity or bioavailability of vitamers, and then consider alternative approaches and possible ways to improve the reporting of data. Major examples are taken from literature and experience with vitamin B6 and folate. PMID:22489223

  20. Bioavailability of soil-sorbed biphenyl to bacteria

    SciTech Connect

    Feng, Y.; Park, J.H.; Voice, T.C.; Boyd, S.A.

    2000-05-15

    Limited bioavailability of organic pollutants in soil may be a detriment to the successful application of bioremediation. The availability of soil-sorbed biphenyl to two biphenyl-degrading bacteria, Pseudomonas putida P106 and Rhodococcus erythropolis NY05, was assessed using a kinetic mineralization assay. Biphenyl was aged in four soils of different organic carbon (OC) contents for up to 274 days. With a biphenyl-soil contact time of 24 h, the initial mineralization rates (IMRs) ranged from 2.6 to 3.5 {micro}g{sm_bullet}L{sup {minus}1}{sm_bullet}min{sup {minus}1} for strain P106 and from 3.8 to 0.92 {micro}g{sm_bullet}L{sup {minus}1}{sm_bullet}min{sup {minus}1} for strain NY05. These IMRs were higher than those of soil-free controls and those predicted by a coupled desorption/biodegradation model, suggesting both strains of bacteria could access soil-sorbed biphenyl. For strain P106, biphenyl mineralization curves in slurries of four different soils were nearly coincident with those in soil-free systems containing the same total mass of biphenyl. This strain appeared to have immediate and complete access to the pool of sorbed biphenyl. The extent of bioavailability of soil-sorbed biphenyl decreased with increased aging. The decrease in availability was most pronounced within the first 80 days. The effect of soil organic matter content on bioavailability showed different trends for the two organisms.