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Sample records for chlorella vulgaris arc

  1. Biomass Production Potential of a Wastewater Alga Chlorella vulgaris ARC 1 under Elevated Levels of CO2 and Temperature

    PubMed Central

    Chinnasamy, Senthil; Ramakrishnan, Balasubramanian; Bhatnagar, Ashish; Das, Keshav C.

    2009-01-01

    The growth response of Chlorella vulgaris was studied under varying concentrations of carbon dioxide (ranging from 0.036 to 20%) and temperature (30, 40 and 50°C). The highest chlorophyll concentration (11 μg mL–1) and biomass (210 μg mL–1), which were 60 and 20 times more than that of C. vulgaris at ambient CO2 (0.036%), were recorded at 6% CO2 level. At 16% CO2 level, the concentrations of chlorophyll and biomass values were comparable to those at ambient CO2 but further increases in the CO2 level decreased both of them. Results showed that the optimum temperature for biomass production was 30°C under elevated CO2 (6%). Although increases in temperature above 30°C resulted in concomitant decrease in growth response, their adverse effects were significantly subdued at elevated CO2. There were also differential responses of the alga, assessed in terms of NaH14CO3 uptake and carbonic anhydrase activity, to increases in temperature at elevated CO2. The results indicated that Chlorella vulgaris grew better at elevated CO2 level at 30°C, albeit with lesser efficiencies at higher temperatures. PMID:19333419

  2. Coagulation-membrane filtration of Chlorella vulgaris.

    PubMed

    Lee, Duu-Jong; Liao, Guan-Yu; Chang, Yin-Ru; Chang, Jo-Shu

    2012-03-01

    Filtration-based separation of Chlorella vulgaris, a species with excellent potential for CO(2) capture and lipid production, was investigated using a surface-modified hydrophilic polytetrafluoroethylene (PTFE) membrane. Coagulation using polyaluminum chloride (PACl) attained maximum turbidity removal at 200 mg L(-1) as Al(2)O(3). The membrane filtration flux at 1 bar increased as the PACl dose increased, regardless of overdosing in the coagulation stage. The filtered cake at the end of filtration tests peaked in solid content at 10 mg L(-1) as Al(2)O(3), reaching 34% w/w, roughly two times that of the original suspension. Differential scanning calorimetry (DSC) tests demonstrate that the cake with minimum water-solid binding strength produced the driest filter cake. Coagulation using 10 mg L(-1) PACl as Al(2)O(3), followed by PTFE membrane filtration at 1 bar, is an effective process for harvesting C. vulgaris from algal froth.

  3. Dispersed ozone flotation of Chlorella vulgaris.

    PubMed

    Cheng, Ya-Ling; Juang, Yu-Chuan; Liao, Guan-Yu; Ho, Shih-Hsin; Yeh, Kuei-Ling; Chen, Chun-Yen; Chang, Jo-Shu; Liu, Jhy-Chern; Lee, Duu-Jong

    2010-12-01

    Flotation separation of Chlorella vulgaris, a species with excellent potential for CO(2) capture and lipid production, was studied using dispersed ozone gas. Pure oxygen aeration did not yield flotation. Conversely, applying ozone effectively separation algae from broth through flotation. The ozone dose applied for sufficient algal flotation is <0.05 mg/g biomass, much lower than those used in practical drinking waterworks (0.1-0.3 mg/g suspended solids). Main products, lipid C16:0, was effectively collected in the flotage phase. The algae removal rate, surface charge, and hydrophobicity of algal cells, and proteins and polysaccharides contents of algogenic organic matter (AOM) were determined. Certain quantities of proteins were present in the cultivated algal suspension, hence, minimal quantity of ozone was required to release intracellular proteins as surfactants to lead to effective flotation.

  4. Bioaccessibility of carotenoids from Chlorella vulgaris and Chlamydomonas reinhardtii.

    PubMed

    Gille, Andrea; Trautmann, Andreas; Posten, Clemens; Briviba, Karlis

    2015-08-01

    Microalgae can contribute to a balanced diet because of their composition. Beside numerous essential nutrients, carotenoids are in the focus for food applications. The bioavailability of carotenoids from photoautotrophic-cultivated Chlorella vulgaris (C. vulgaris) and Chlamydomonas reinhardtii (C. reinhardtii) was compared. An in vitro digestion model was used to investigate carotenoid bioaccessibility. Furthermore, the effect of sonication on bioaccessibility was assessed. Lutein was the main carotenoid in both species. C. reinhardtii showed higher amounts of lutein and β-carotene than C. vulgaris. In contrast to C. reinhardtii, no β-carotene and only 7% of lutein were bioaccessible in nonsonicated C. vulgaris. Sonication increased the bioaccessibility of carotenoids from C. vulgaris to a level comparable with C. reinhardtii (β-carotene: ≥ 10%; lutein: ≥ 15%). Thus, C. reinhardtii represents a good carotenoid source for potential use in foods without processing, while the application of processing methods, like sonication, is necessary for C. vulgaris.

  5. Epigenetic modulation of Chlorella (Chlorella vulgaris) on exposure to polycyclic aromatic hydrocarbons.

    PubMed

    Yang, Mihi; Youn, Je-In; Kim, Seung Joon; Park, Jong Y

    2015-11-01

    DNA methylation in promoter region can be a new chemopreventive marker against polycyclic aromatic hydrocarbons (PAHs). We performed a randomized, double blind and cross-over trial (N=12 healthy females) to evaluate chlorella (Chlorella vulgaris)-induced epigenetic modulation on exposure to PAHs. The subjects consumed 4 tablets of placebo or chlorella supplement (total chlorophyll ≈ 8.3mg/tablet) three times a day before meals for 2 weeks. When the subjects consumed chlorella, status of global hypermethylation (5-methylcytosine) was reduced, compared to placebo (p=0.04). However, DNA methylation at the DNMT1 or NQO1 was not modified by chlorella. We observed the reduced levels of urinary 1-hydroxypyrene (1-OHP), a typical metabolite of PAHs, by chlorella intake (p<0.1) and a positive association between chlorella-induced changes in global hypermethylation and urinary 1-OHP (p<0.01). Therefore, our study suggests chlorella works for PAH-detoxification through the epigenetic modulation, the interference of ADME of PAHs and the interaction of mechanisms.

  6. Vitreoscilla hemoglobin gene ( vgb) improves lutein production in Chlorella vulgaris

    NASA Astrophysics Data System (ADS)

    Ma, Ruijuan; Lin, Xiangzhi

    2014-03-01

    Vitreoscilla hemoglobin is an oxygen-binding protein that promotes oxygen delivery and reduces oxygen consumption under low oxygen conditions to increase the efficiency of cell respiration and metabolism. In this study, we introduced a Vitreoscilla hemoglobin gene ( vgb) into Chlorella vulgaris by Agrobacterium tumefaciens -mediated transformation (ATMT). PCR analysis confirmed that the vgb gene was successfully integrated into the Chlorella vulgaris genome. Analysis of biomass obtained in shake flasks revealed transformant biomass concentrations as high as 3.28 g/L, which was 38.81% higher than that of the wild-type strain. Lutein content of transformants also increased slightly. Further experiments recovered a maximum lutein yield of 2.91 mg/L from the transformants, which was 36.77% higher than that of the wild-type strain. The above results suggest that integrated expression of the vgb gene may improve cell growth and lutein yield in Chlorella vulgaris, with applications to lutein production from Chlorella during fermentation.

  7. Effect of aniline on Chlorella vulgaris

    SciTech Connect

    Amman, H.M.; Terry, b.

    1985-08-01

    A direct correlation between concentration of waste effluent, including aniline, released by a dye company into a waterway in Eastern North Carolina, and the rise and fall of populations of Chlorella, was demonstrated previously. The present study establishes threshold concentrations of aniline which affect growth of these algae, but also shows that physiologic parameters within the organism, such as the rate of photosynthesis, were decreased as sub-threshold concentrations of toxicant.

  8. Recycling of food waste as nutrients in Chlorella vulgaris cultivation.

    PubMed

    Lau, Kin Yan; Pleissner, Daniel; Lin, Carol Sze Ki

    2014-10-01

    Heterotrophic cultivation of Chlorella vulgaris was investigated in food waste hydrolysate. The highest exponential growth rate in terms of biomass of 0.8day(-1) was obtained in a hydrolysate consisting of 17.9gL(-1) glucose, 0.1gL(-1) free amino nitrogen, 0.3gL(-1) phosphate and 4.8mgL(-1) nitrate, while the growth rate was reduced in higher concentrated hydrolysates. C. vulgaris utilized the nutrients recovered from food waste for the formation of biomass and 0.9g biomass was produced per gram glucose consumed. The microalgal biomass produced in nutrient sufficient batch cultures consisted of around 400mgg(-1) carbohydrates, 200mgg(-1) proteins and 200mgg(-1) lipids. The conversion of nutrients derived from food waste and the balanced biomass composition make C. vulgaris a promising strain for the recycling of food waste in food, feed and fuel productions.

  9. [Research on characteristic of interrelationship between toxic organic compound BPA and Chlorella vulgaris].

    PubMed

    Chen, Shan-Jia; Chen, Xiu-Rong; Yan, Long; Zhao, Jian-Guo; Zhang, Fei; Jiang, Zi-Jian

    2014-04-01

    The effects of different concentrations of bisphenol A (BPA) on Chlorella vulgaris and removal capacity of BPA by Chlorella vulgaris were investigated. Results showed that a low concentration (0-20 mg x L(-1)) of BPA promoted the growth of Chlorella vulgaris, whereas a relative high concentration (20-50 mg x L(-1)) of BPA inhibited the growth of Chlorella vulgaris, and the inhibition effect was positively correlated with the concentration of BPA. Likewise, a high dose of initial BPA (> 20 mg x L(-1)) led to a decline in the content of chlorephyll a. Chlorella vulgaris had BPA removal capacity when initial BPA concentration ranged from 2 mg x L(-1) to 50 mg x L(-1). There was positive correlation between the removal rate of BPA per cell and initial BPA concentration. The removal rate of BPA was the highest when initial BPA was 50 mg x L(-1), which appeared between lag phase and logarithmic phase.

  10. Biodiesel production in crude oil contaminated environment using Chlorella vulgaris.

    PubMed

    Xaaldi Kalhor, Aadel; Mohammadi Nassab, Adel Dabbagh; Abedi, Ehsan; Bahrami, Ahmad; Movafeghi, Ali

    2016-12-01

    Biodiesel is a valuable alternative to fossil fuels and many countries choose biodiesel as an unconventional energy source. A large number of investigations have been done on microalgae as a source of oil production. In recent years, wastewater pollutions have caused many ecological problems, and therefore, wastewater phycoremediation has attracted the international attention. This paper studied the cultivation of Chlorella vulgaris in a crude oil polluted environment for biodiesel production. Intended concentrations were 10 and 20gperliter (crude oil/water) at two times. The results showed that the growth of C. vulgaris was improved in wastewater and the maximum amount of dry mass and oil was produced at the highest concentration of crude oil (0.41g and 0.15g/l, respectively). In addition, dry mass and oil yield of the microalga were significantly enhanced by increasing the experiment duration.

  11. Stability and loading properties of curcumin encapsulated in Chlorella vulgaris.

    PubMed

    Jafari, Yaser; Sabahi, Hossein; Rahaie, Mahdi

    2016-11-15

    Curcumin (Cur), a polyphenols with pharmacological function, was successfully encapsulated in algae (Alg) cell (Chlorella vulgaris) as confirmed by fluorescence microscopy, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and Fourier transform-infrared spectroscopy (FT-IR). Fluorescence micrographs, TGA, DSC and FTIR spectra suggested the hypothesis inclusion Cur in Nano-empty spaces inside cell wall of Alg. The TGA analysis showed that the thermal stability of Alg and Cur at algae/curcumin complex was 3.8% and 33% higher than their free forms at 0-300°C and 300-600°C ranges, respectively. After encapsulation in Alg cells, the photostability of Cur was enhanced by about 2.5-fold. Adsorption isotherm of Cur into Alg was fitted with the Freundlich isotherm. The microcapsules were loaded with Cur up to about 55% w/w which is much higher than other reported bio-carriers. In conclusion, the data proved that Chlorella vulgaris cell can be used as a new stable carrier for Cur.

  12. Enhancement of hydrolysis of Chlorella vulgaris by hydrochloric acid.

    PubMed

    Park, Charnho; Lee, Ja Hyun; Yang, Xiaoguang; Yoo, Hah Young; Lee, Ju Hun; Lee, Soo Kweon; Kim, Seung Wook

    2016-06-01

    Chlorella vulgaris is considered as one of the potential sources of biomass for bio-based products because it consists of large amounts of carbohydrates. In this study, hydrothermal acid hydrolysis with five different acids (hydrochloric acid, nitric acid, peracetic acid, phosphoric acid, and sulfuric acid) was carried out to produce fermentable sugars (glucose, galactose). The hydrothermal acid hydrolysis by hydrochloric acid showed the highest sugar production. C. vulgaris was hydrolyzed with various concentrations of hydrochloric acid [0.5-10 % (w/w)] and microalgal biomass [20-140 g/L (w/v)] at 121 °C for 20 min. Among the concentrations examined, 2 % hydrochloric acid with 100 g/L biomass yielded the highest conversion of carbohydrates (92.5 %) into reducing sugars. The hydrolysate thus produced from C. vulgaris was fermented using the yeast Brettanomyces custersii H1-603 and obtained bioethanol yield of 0.37 g/g of algal sugars.

  13. Growth of Chlorella vulgaris and associated bacteria in photobioreactors.

    PubMed

    Lakaniemi, Aino-Maija; Intihar, Veera M; Tuovinen, Olli H; Puhakka, Jaakko A

    2012-01-01

    The aim of this study was to test three flat plate photobioreactor configurations for growth of Chlorella vulgaris under non-axenic conditions and to characterize and quantify associated bacterial communities. The photobioreactor cultivations were conducted using tap water-based media to introduce background bacterial population. Growth of algae was monitored over time with three independent methods. Additionally, the quantity and quality of eukaryotes and bacteria were analysed using culture-independent molecular tools based on denaturing gradient gel electrophoresis (PCR-DGGE) and quantitative polymerase chain reaction (QPCR). Static mixers used in the flat plate photobioreactors did not generally enhance the growth at the low light intensities used. The maximum biomass concentration and maximum specific growth rate were 1.0 g l(-1) and 2.0 day(-1) respectively. Bacterial growth as determined by QPCR was associated with the growth of C. vulgaris. Based on PCR-DGGE, bacteria in the cultures mainly originated from the tap water. Bacterial community profiles were diverse but reproducible in all flat plate cultures. Most prominent bacteria in the C. vulgaris cultures belonged to the class Alphaproteobacteria and especially to the genus Sphingomonas. Analysis of the diversity of non-photosynthetic microorganisms in algal mass cultures can provide useful information on the public health aspects and unravel community interactions.

  14. Growth of Chlorella vulgaris and associated bacteria in photobioreactors

    PubMed Central

    Lakaniemi, Aino‐Maija; Intihar, Veera M.; Tuovinen, Olli H.; Puhakka, Jaakko A.

    2012-01-01

    Summary The aim of this study was to test three flat plate photobioreactor configurations for growth of Chlorella vulgaris under non‐axenic conditions and to characterize and quantify associated bacterial communities. The photobioreactor cultivations were conducted using tap water‐based media to introduce background bacterial population. Growth of algae was monitored over time with three independent methods. Additionally, the quantity and quality of eukaryotes and bacteria were analysed using culture‐independent molecular tools based on denaturing gradient gel electrophoresis (PCR‐DGGE) and quantitative polymerase chain reaction (QPCR). Static mixers used in the flat plate photobioreactors did not generally enhance the growth at the low light intensities used. The maximum biomass concentration and maximum specific growth rate were 1.0 g l−1 and 2.0 day−1 respectively. Bacterial growth as determined by QPCR was associated with the growth of C. vulgaris. Based on PCR‐DGGE, bacteria in the cultures mainly originated from the tap water. Bacterial community profiles were diverse but reproducible in all flat plate cultures. Most prominent bacteria in the C. vulgaris cultures belonged to the class Alphaproteobacteria and especially to the genus Sphingomonas. Analysis of the diversity of non‐photosynthetic microorganisms in algal mass cultures can provide useful information on the public health aspects and unravel community interactions. PMID:21936882

  15. Physiological and biochemical responses of Chlorella vulgaris to Congo red.

    PubMed

    Hernández-Zamora, Miriam; Perales-Vela, Hugo Virgilio; Flores-Ortíz, César Mateo; Cañizares-Villanueva, Rosa Olivia

    2014-10-01

    Extensive use of synthetic dyes in many industrial applications releases large volumes of wastewater. Wastewaters from dying industries are considered hazardous and require careful treatment prior to discharge into receiving water bodies. Dyes can affect photosynthetic activities of aquatic flora and decrease dissolved oxygen in water. The aim of this study was to evaluate the effect of Congo red on growth and metabolic activity of Chlorella vulgaris after 96h exposure. Exposure of the microalga to Congo red reduced growth rate, photosynthesis and respiration. Analysis of chlorophyll a fluorescence emission showed that the donor side of photosystem II was affected at high concentrations of Congo red. The quantum yield for electron transport (φEo), the electron transport rate (ETR) and the performance index (PI) also decreased. The reduction in the ability to absorb and use the quantum energy increased non-photochemical (NPQ) mechanisms for thermal dissipation. Overall, Congo red affects growth and metabolic activity in photosynthetic organisms in aquatic environments.

  16. Polyphosphate during the Regreening of Chlorella vulgaris under Nitrogen Deficiency

    PubMed Central

    Chu, Fei-Fei; Shen, Xiao-Fei; Lam, Paul K. S.; Zeng, Raymond J.

    2015-01-01

    Polyphosphate (Poly-P) accumulation has been reported in Chlorella vulgaris under nitrogen deficiency conditions with sufficient P supply, and the process has been demonstrated to have great impact on lipid productivity. In this article, the utilization of polyphosphates and the regreening process under N resupplying conditions, especially for lipid production reviving, were investigated. This regreening process was completed within approximately 3–5 days. Polyphosphates were first degraded within 3 days in the regreening process, with and without an external P supply, and the degradation preceded the assimilation of phosphate in the media with an external P offering. Nitrate assimilation was markedly influenced by the starvation of P after polyphosphates were exhausted in the medium without external phosphates, and then the reviving process of biomass and lipid production was strictly impeded. It is, thus, reasonable to assume that simultaneous provision of external N and P is essential for overall biodiesel production revival during the regreening process. PMID:26426008

  17. Toxicological Responses of Chlorella vulgaris to Dichloromethane and Dichloroethane

    PubMed Central

    Wu, Shijin; Zhang, Huaxing; Yu, Xiang; Qiu, Lequan

    2014-01-01

    Abstract The aim of this study was to evaluate the acute toxicity effects of dichloromethane and dichloroethane on Chlorella vulgaris at the physiological and molecular level. Data showed that the cell number, chlorophyll a, and total protein content gradually decreased with increasing dichloromethane and dichloroethane concentrations over a 96-h exposure. Lower doses of two organic solvents had stimulatory effects on catalase and superoxide dismutase activity. Malondialdehyde showed a concentration-dependent increase in response to dichloromethane and dichloroethane exposure. Electron microscopy also showed that there were some chloroplast abnormalities in response to different concentrations of dichloromethane and dichloroethane exposure. Real-time polymerase chain reaction assay demonstrated that dichloromethane and dichloroethane reduced the transcript abundance of psaB, whereas that of psbC changed depending on the toxicant after 24 h of exposure. Dichloromethane and dichloroethane affected the activity of antioxidant enzymes, disrupted the chloroplast ultrastructure, and reduced transcription of photosynthesis-related genes in C. vulgaris, leading to metabolic disruption and cell death. PMID:24550665

  18. The culture of Chlorella vulgaris with human urine in multibiological life support system experiments

    NASA Astrophysics Data System (ADS)

    Li, Ming; Liu, Hong; Tong, Ling; Fu, Yuming; He, Wenting; Hu, Enzhu; Hu, Dawei

    The Integrative Experimental System (IES) was established as a tool to evaluate the rela-tionship of the subsystems in Bioregenerative Life Support System, and Multibiological Life Support System Experiments (MLSSE) have been conducted in the IES. The IES consists of a higher plant chamber, an animal chamber and a plate photo bioreactor (PPB) which cultivated lettuce (Lactuca sativa L.), silkworm (Bombyx Mori L.) and microalgae (Chlorella vulgaris), respectively. In MLSSE, four volunteers took turns breathing the system air through a tube connected with the animal chamber periodically. According to the CO2 concentration in the IES, the automotive control system of the PPB changed the light intensity regulating the photosynthesis of Chlorella vulgaris to make CO2 /O2 in the system maintain at stable levels. Chlorella vulgaris grew with human urine by carrying certain amount of alga liquid out of the bioreactor every day with synthetic urine replenished into the system, and O2 was regenerated, at the same time human urine was purified. Results showed that this IES worked stably and Chlorella vulgaris grew well; The culture of Chlorella vulgaris could be used to keep the balance of CO2 and O2 , and the change of light intensity could control the gas composition in the IES; Microalgae culture could be used in emergency in the system, the culture of Chlorella vulgaris could recover to original state in 5 days; 15.6 ml of condensation water was obtained every day by the culture of Chlorella vulgaris; The removal efficiencies of N, P in human urine could reach to 98.2% and 99.5%.

  19. Hot water extract of Chlorella vulgaris induced DNA damage and apoptosis

    PubMed Central

    Yusof, Yasmin Anum Mohd; Md. Saad, Suhana; Makpol, Suzana; Shamaan, Nor Aripin; Ngah, Wan Zurinah Wan

    2010-01-01

    OBJECTIVES: The aim of this study was to determine the antiproliferative and apoptotic effects of hot water extracts of Chlorella vulgaris on hepatoma cell line HepG2. INTRODUCTION: The search for food and spices that can induce apoptosis in cancer cells has been a major study interest in the last decade. Chlorella vulgaris, a unicellular green algae, has been reported to have antioxidant and anti‐cancer properties. However, its chemopreventive effects in inhibiting the growth of cancer cells have not been studied in great detail. METHODS: HepG2 liver cancer cells and WRL68 normal liver cells were treated with various concentrations (0‐4 mg/ml) of hot water extract of C. vulgaris after 24 hours incubation. Apoptosis rate was evaluated by TUNEL assay while DNA damage was assessed by Comet assay. Apoptosis proteins were evaluated by Western blot analysis. RESULTS: Chlorella vulgaris decreased the number of viable HepG2 cells in a dose dependent manner (p < 0.05), with an IC50 of 1.6 mg/ml. DNA damage as measured by Comet assay was increased in HepG2 cells at all concentrations of Chlorella vulgaris tested. Evaluation of apoptosis by TUNEL assay showed that Chlorella vulgaris induced a higher apoptotic rate (70%) in HepG2 cells compared to normal liver cells, WRL68 (15%). Western blot analysis showed increased expression of pro‐ apoptotic proteins P53, Bax and caspase‐3 in the HepG2 cells compared to normal liver cells WRL68, and decreased expression of the anti‐apoptotic protein Bcl‐2. CONCLUSIONS: Chlorella vulgaris may have anti‐cancer effects by inducing apoptosis signaling cascades via an increased expression of P53, Bax and caspase‐3 proteins and through a reduction of Bcl‐2 protein, which subsequently lead to increased DNA damage and apoptosis. PMID:21340229

  20. Use of diluted urine for cultivation of Chlorella vulgaris.

    PubMed

    Jaatinen, Sanna; Lakaniemi, Aino-Maija; Rintala, Jukka

    2016-01-01

    Our aim was to study the biomass growth of microalga Chlorella vulgaris using diluted human urine as a sole nutrient source. Batch cultivations (21 days) were conducted in five different urine dilutions (1:25-1:300), in 1:100-diluted urine as such and with added trace elements, and as a reference, in artificial growth medium. The highest biomass density was obtained in 1:100-diluted urine with and without additional trace elements (0.73 and 0.60 g L(-1), respectively). Similar biomass growth trends and densities were obtained with 1:25- and 1:300-diluted urine (0.52 vs. 0.48 gVSS L(-1)) indicating that urine at dilution 1:25 can be used to cultivate microalgal based biomass. Interestingly, even 1:300-diluted urine contained sufficiently nutrients and trace elements to support biomass growth. Biomass production was similar despite pH-variation from < 5 to 9 in different incubations indicating robustness of the biomass growth. Ammonium formation did not inhibit overall biomass growth. At the beginning of cultivation, the majority of the biomass consisted of living algal cells, while towards the end, their share decreased and the estimated share of bacteria and cell debris increased.

  1. [Using Excess Activated Sludge Treated 4-Chlorophenol Contained Waste Water to Cultivate Chlorella vulgaris].

    PubMed

    Wang, Lu; Chen, Xiu-rong; Yan, Long; He, Yi-xuan; Shi, Zhen-dong

    2015-04-01

    Using different rations of sludge extracts and supernate from 4-Chlorophenol (4-CP) simulated wastewater's excess sludge after centrifugation to cultivate the Chlorella vulgaris to achieve the goal of excess sludge utilization together with chlorella cultivating. The experiments were performed in 500 mL flasks with different rations of sludge extracts & BG-11 and supernate & BG-11 in a light growth chamber respectively. Number of algal cells, Chlorophyll, enzyme activity, oil and water total nitrogen (TN), total phosphorus (TP), total organic carbon (TOC), toxicity index were investigated. Result showed that the nutrition supplies and toxicity in the excess sludge were removed efficiently via Chlorella vulgaris, the removal rates of TN and TP were at least 40% and 90% respectively; After 10 days cultivation, the density growth of 50% sludge extracts was 20 times higher of the beginning while its chlorophyll content was lower than that of the blank group. Sludge extracts could promote the proliferation of algae, but were not conducive to the synthesis of chlorophyll. The quantity of SOD in per cell showed Chlorella vulgaris gave a positive response via stimulation from toxicant in sludge extracts and supernate. The best time for collecting chlorella vulgaris was the fifth day of cultivation, taking neutral oil accumulation as the evaluating indicator for its utilization combined with the removal of supplies and toxicity.

  2. Characterization of iron uptake from hydroxamate siderophores by Chlorella vulgaris

    SciTech Connect

    Allnutt, F.C.T.

    1985-01-01

    Iron uptake by Chlorella vulgaris from ferric-hydroxamate siderophores and the possible production of siderophores by these algae was investigated. No production of siderophores or organic acids was observed. Iron from the two hydroxamate siderophores tested, ferrioximine B (Fe/sup 3 +/-DFOB) and ferric-rhodotorulate (Fe/sup 3 +/-RA), was taken up at the same rate as iron chelated by citrate or caffeate. Two synthetic chelates, Fe/sup 3 +/-EDTA and Fe/sup 3 +/-EDDHA, provided iron at a slower rate. Iron uptake was inhibited by 50 ..mu..M CCCP or 1 mM vanadate. Cyanide (100 ..mu..M KCN) or 25 ..mu..M antimycin A failed to demonstrate a link between uptake and respiration. Labeled iron (/sup 55/Fe) was taken up while labeled ligands ((/sup 14/C) citrate or RA) were not accumulated. Cation competition from Ni/sup 2 +/ and Co/sup 2 +/ observed using Fe/sup 3 +/-DFOB and Fe/sup 3 +/-RA while iron uptake from Fe/sup 3 +/-citrate was stimulated. Iron-stress induced iron uptake from the hydroxamate siderophores. Ferric reduction from the ferric-siderophores was investigated with electron paramagnetic resonance (EPR) and bathophenathroline disulfonate (BPDS). Ferric reduction was induced by iron-stress and inhibited by CCCP. A close correlation between iron uptake and ferric reduction was measured by the EPR method. Ferric reduction measured by the BPDS method was greater than that measure by EPR. BPDS reduction was interpreted to indicate a potential for reduction while EPR measures the physiological rate of reduction. BPDS inhibition of iron uptake and ferricyanide interference with reduction indicate that reduction and uptake occur exposed to the external medium. Presumptive evidence using a binding dose response curve for Fe/sup 3 +/-DFOB indicated that a receptor may be involved in this mechanism.

  3. The Use of Chlorella Vulgaris in a Simple Demonstration of Heavy Metal Toxicity.

    ERIC Educational Resources Information Center

    Gipps, J. F.; Biro, P.

    1978-01-01

    An experimental system, suitable for secondary schools, uses Chlorella vulgaris to demonstrate the effects of mercury and cadmium. Very low concentrations of mercury or cadmium decrease growth, whereas lead or arsenic have little effect. Further experiments show additive interactions between mercury and cadmium and antagonistic interactions…

  4. Caleosin from Chlorella vulgaris TISTR 8580 is salt-induced and heme-containing protein.

    PubMed

    Charuchinda, Pairpilin; Waditee-Sirisattha, Rungaroon; Kageyama, Hakuto; Yamada, Daisuke; Sirisattha, Sophon; Tanaka, Yoshito; Mahakhant, Aparat; Takabe, Teruhiro

    2015-01-01

    Physiological and functional properties of lipid droplet-associated proteins in algae remain scarce. We report here the caleosin gene from Chlorella vulgaris encodes a protein of 279 amino acid residues. Amino acid sequence alignment showed high similarity to the putative caleosins from fungi, but less to plant caleosins. When the C. vulgaris TISTR 8580 cells were treated with salt stress (0.3 M NaCl), the level of triacylglycerol increased significantly. The mRNA contents for caleosin in Chlorella cells significantly increased under salt stress condition. Caleosin gene was expressed in E. coli. Crude extract of E. coli cells exhibited the cumene hydroperoxide-dependent oxidation of aniline. Absorption spectroscopy showed a peak around 415 nm which was decreased upon addition of cumene hydroperoxide. Native polyacrylamide gel electrophoresis suggests caleosin existed as the oligomer. These data indicate that a fresh water C. vulgaris TISTR 8580 contains a salt-induced heme-protein caleosin.

  5. Mixotrophic growth and biochemical analysis of Chlorella vulgaris cultivated with diluted monosodium glutamate wastewater.

    PubMed

    Ji, Yan; Hu, Wenrong; Li, Xiuqing; Ma, Guixia; Song, Mingming; Pei, Haiyan

    2014-01-01

    Monosodium glutamate wastewater (MSGW) is a potential medium for microbial cultivation because of containing abundant organic nutrient. This paper seeks to evaluate the feasibility of growing Chlorella vulgaris with MSGW and assess the influence of MSGW concentration on the biomass productivity and biochemical compositions. The MSGW diluted in different concentrations was prepared for microalga cultivation. C. vulgaris growth was greatly promoted with MSGW compared with the inorganic BG11 medium. C. vulgaris obtained the maximum biomass concentration (1.02 g/L) and biomass productivity (61.47 mg/Ld) with 100-time diluted MSGW. The harvested biomass was rich in protein (36.01-50.64%) and low in lipid (13.47-25.4%) and carbohydrate (8.94-20.1%). The protein nutritional quality and unsaturated fatty acids content of algal increased significantly with diluted MSGW. These results indicated that the MSGW is a feasible alternative for mass cultivation of C. vulgaris.

  6. Effects of nickel and pH on the growth of Chlorella vulgaris

    SciTech Connect

    Lustigman, B.; Lee, L.H.; Khalil, A.

    1995-07-01

    Chlorella is a spherical, unicellular, eukaryotic green algae. It is an obligate photoautotrophy containing chlorophylls a and b. It is a frequent symbiont of many other organisms such as paramecium, hydra and sponges and is important in fresh and marine environments, as well as in the soil. For these reasons, it has been suggested that Chlorella be used for metabolic studies as an indicator of environmental pollution. Ability of microorganisms to grow in environments containing high levels of toxic metals is frequently due to the organisms` capacity for adsorption of these ions and the role that they may play as essential cofactors in metalloenzymes as is the case for nickel. The purpose of this study was to determine the effect of nickel on the growth of Chlorella vulgaris. 19 refs., 4 figs., 1 tab.

  7. Impact of light quality on biomass production and fatty acid content in the microalga Chlorella vulgaris.

    PubMed

    Hultberg, Malin; Jönsson, Helene Larsson; Bergstrand, Karl-Johan; Carlsson, Anders S

    2014-05-01

    In this study, the green microalga Chlorella vulgaris was exposed to monochromatic light at six different wavelengths in order to study the effect on biomass productivity and fatty acid content. A significantly higher amount of biomass by produced in the treatments with yellow, red and white light compared with blue, green and purple light. There were also significant differences in total lipid content and fatty acid profile between the treatments. The green light regime gave the lowest concentration of lipids, but increased the concentration of polyunsaturated fatty acids. Thus it can be concluded that light quality significantly affects biomass productivity, total lipid concentration and fatty acid profile in the microalga C. vulgaris.

  8. Development and validation of a minimal growth medium for recycling Chlorella vulgaris culture.

    PubMed

    Hadj-Romdhane, F; Jaouen, P; Pruvost, J; Grizeau, D; Van Vooren, G; Bourseau, P

    2012-11-01

    When microalgae culture medium is recycled, ions (e.g. Na(+), K(+), Ca(2+)) that were not assimilated by the microalgae accumulate in the medium. Therefore, a growth medium (HAMGM) was developed that included ions that were more easily assimilated by Chlorella vulgaris, such as ammonium one (NH(4)(+)). Recycling performance was studied by carrying out 8-week continuous cultivation of C. vulgaris with recycled HAMGM medium. No loss of biomass productivity was observed compared to culture in a conventional medium, and accumulation of ions over time was negligible.

  9. Development of novel microsatellite markers for strain-specific identification of Chlorella vulgaris.

    PubMed

    Jo, Beom-Ho; Lee, Chang Soo; Song, Hae-Ryong; Lee, Hyung-Gwan; Oh, Hee-Mock

    2014-09-01

    A strain-specific identification method is required to secure Chlorella strains with useful genetic traits, such as a fast growth rate or high lipid productivity, for application in biofuels, functional foods, and pharmaceuticals. Microsatellite markers based on simple sequence repeats can be a useful tool for this purpose. Therefore, this study developed five novel microsatellite markers (mChl-001, mChl-002, mChl-005, mChl-011, and mChl-012) using specific loci along the chloroplast genome of Chlorella vulgaris. The microsatellite markers were characterized based on their allelic diversities among nine strains of C. vulgaris with the same 18S rRNA sequence similarity. Each microsatellite marker exhibited 2~5 polymorphic allele types, and their combinations allowed discrimination between seven of the C. vulgaris strains. The two remaining strains were distinguished using one specific interspace region between the mChl-001 and mChl-005 loci, which was composed of about 27 single nucleotide polymorphisms, 13~15 specific sequence sites, and (T)n repeat sites. Thus, the polymorphic combination of the five microsatellite markers and one specific locus facilitated a clear distinction of C. vulgaris at the strain level, suggesting that the proposed microsatellite marker system can be useful for the accurate identification and classification of C. vulgaris.

  10. Bioremoval of the azo dye Congo Red by the microalga Chlorella vulgaris.

    PubMed

    Hernández-Zamora, Miriam; Cristiani-Urbina, Eliseo; Martínez-Jerónimo, Fernando; Perales-Vela, Hugo Virgilio; Ponce-Noyola, Teresa; Montes-Horcasitas, María del Carmen; Cañizares-Villanueva, Rosa Olivia

    2015-07-01

    Discharge of dye-containing wastewater by the textile industry can adversely affect aquatic ecosystems and human health. Bioremoval is an alternative to industrial processes for detoxifying water contaminated with dyes. In this work, active and inactive biomass of the microalga Chlorella vulgaris was assayed for the ability to remove Congo Red (CR) dye from aqueous solutions. Through biosorption and biodegradation processes, Chlorella vulgaris was able to remove 83 and 58 % of dye at concentrations of 5 and 25 mg L(-1), respectively. The maximum adsorption capacity at equilibrium was 200 mg g(-1). The Langmuir model best described the experimental equilibrium data. The acute toxicity test (48 h) with two species of cladocerans indicated that the toxicity of the dye in the effluent was significantly decreased compared to the initial concentrations in the influent. Daphnia magna was the species less sensitive to dye (EC50 = 17.0 mg L(-1)), followed by Ceriodaphnia dubia (EC50 = 3.32 mg L(-1)). These results show that Chlorella vulgaris significantly reduced the dye concentration and toxicity. Therefore, this method may be a viable option for the treatment of this type of effluent.

  11. Effects of Pb(Ⅱ) exposure on Chlorella protothecoides and Chlorella vulgaris growth, malondialdehyde, and photosynthesis-related gene transcription.

    PubMed

    Xiong, Bang; Zhang, Wei; Chen, Lin; Lin, Kuang-Fei; Guo, Mei-Jin; Wang, Wei-Liang; Cui, Xin-Hong; Bi, Hua-Song; Wang, Bin

    2014-11-01

    Greater exposure to Pb(Ⅱ) increases the likelihood of harmful effects in the environment. In this study, the aquatic unicellular alga Chlorella protothecoides (C. protothecoides) and Chlorella vulgaris (C. vulgaris) were chosen to assess the acute and chronic toxicity of Pb(Ⅱ) exposure. Results of the observations show dose-response relationships could be clearly observed between Pb(Ⅱ) concentration and percentage inhibition (PI). Exposure to Pb(Ⅱ) increased malondialdehyde (MDA) content by up to 4.22 times compared with the control, suggesting that there was some oxidative damage. ANOVA analysis shows that Pb(Ⅱ) decreased chlorophyll (chl) content, indicating marked concentration-dependent relationships, and the lowest levels of chl a, chl b, and total-chl were 14.53, 18.80, and 17.95% of the controls, respectively. A real-time PCR assay suggests the changes in transcript abundances of three photosynthetic-related genes. After 120 h exposure Pb(Ⅱ) reduced the transcript abundance of rbcL, psaB, and psbC, and the relative abundances of the three genes of C. protothecoides and C. vulgaris in response to Pb(Ⅱ) were 54.66-98.59, 51.68-95.59, 37.89-95.48, 36.04-94.94, 41.19-91.20, and 58.75-96.80% of those of the controls, respectively. As for 28 d treatments, the three genes displayed similar inhibitory trend. This research provides a basic understanding of Pb(Ⅱ) toxicity to aquatic organisms.

  12. Effects of sodium pentaborate pentahydrate exposure on Chlorella vulgaris growth, chlorophyll content, and enzyme activities.

    PubMed

    Chen, Xueqing; Pei, Yuansheng

    2016-10-01

    Sodium pentaborate pentahydrate (SPP) is a rare mineral. In this study, SPP was synthesized from boric acid and borax through low-temperature crystallization, and its effects on the growth of the alga, Chlorella vulgaris (C. vulgaris) were assessed. The newly synthesized SPP was characterized by chemical analysis, X-ray diffraction, Fourier-transform infrared spectroscopy, Raman spectroscopy, thermogravimetric analysis, and differential thermal analysis. The changes in C. vulgaris growth, chlorophyll content, and enzyme activities upon exposure to SPP for 168h were evaluated. Results showed that SPP treatment was detrimental to C. vulgaris growth during the first 24-120h of exposure. The harmful effects, however, diminished over time (168h), even at an effective medium concentration of 226.37mg BL(-1) (the concentration of boron applied per liter of culture medium). A similar trend was observed for chlorophyll content (chlorophyll a and b) and indicated that the photosynthesis of C. vulgaris was not affected and that high levels of SPP may even promote chlorophyll synthesis. Superoxide dismutase and catalase activities of C. vulgaris increased during 24-120h exposure to SPP, but these activities gradually decreased as culture time progressed. In other words, the initial detrimental effects of synthetic SPP on C. vulgaris were temporary and reversible. This research provides a scientific basis for applications of SPP in the environment.

  13. Chlorella vulgaris production enhancement with supplementation of synthetic medium in dairy manure wastewater.

    PubMed

    Shi, Jun; Pandey, Pramod K; Franz, Annaliese K; Deng, Huiping; Jeannotte, Richard

    2016-03-01

    To identify innovative ways for better utilizing flushed dairy manure wastewater, we have assessed the effect of dairy manure and supplementation with synthetic medium on the growth of Chlorella vulgaris. A series of experiments were carried out to study the impacts of pretreatment of dairy wastewater and the benefits of supplementing dairy manure wastewater with synthetic medium on C. vulgaris growth increment and the ultrastructure (chloroplast, starch, lipid, and cell wall) of C. vulgaris cells. Results showed that the biomass production of C. vulgaris in dairy wastewater can be enhanced by pretreatment and using supplementation with synthetic media. A recipe combining pretreated dairy wastewater (40 %) and synthetic medium (60 %) exhibited an improved growth of C. vulgaris. The effects of dairy wastewater on the ultrastructure of C. vulgaris cells were distinct compared to that of cells grown in synthetic medium. The C. vulgaris growth in both synthetic medium and manure wastewater without supplementing synthetic medium was lower than the growth in dairy manure supplemented with synthetic medium. We anticipate that the results of this study will help in deriving an enhanced method of coupling nutrient-rich dairy manure wastewater for biofuel production.

  14. Survey on nitrogen removal and membrane filtration characteristics of Chlorella vulgaris Beij. on treating domestic type wastewaters.

    PubMed

    Wang, Yu-Hsuan; Wu, Chuen-Mei; Wu, Wan-Lin; Chu, Ching-Ping; Chung, Yu-Jen; Liao, Chien-Sen

    2013-01-01

    The main objective of this study is to evaluate the nitrogen assimilation and filtration characteristics of Chlorella vulgaris Beij. when treating domestic wastewaters. Chlorella could assimilate organic nitrogen, ammonia and nitrate in wastewater, and the mean cell residence time (MCRT) to achieve the maximum biomass content in a bioreactor was different for each individual nitrogen source used. The experimental results showed that using nitrate as the only nitrogen source was the most favorable for biomass growth. With ammonia and nitrate coexisting in the aquatic phase, Chlorella possibly utilized ammonia first, and this was unfavorable to subsequent biomass growth. Nitrifying bacteria in wastewaters significantly affected Chlorella growth as they possibly competed with Chlorella in assimilating ammonia and nitrate in domestic wastewater. In a submerged ultrafiltration (UF) membrane module, with an initial concentration of 850 mg/L of Chlorella, the optimized flux was 0.02 m(3)/(m(2)·h), and the filtration cycle was 30 min. A 'dual membrane bioreactor (MBR)' configuration using UF membranes for Chlorella incubation was proposed. MBR1 provides an environment with long MCRT for efficient nitrification. The converted nitrate is assimilated by Chlorella in MBR2 to sustain its growth. UF permeate from MBR1 is bacteria-free and does not affect the growth of Chlorella in MBR2. MCRT of Chlorella growth is controlled by the UF membrane of MBR2, providing the flexibility to adjust variations of nitrogen composition in the wastewater.

  15. Culture of a high-chlorophyll-producing and halotolerant Chlorella vulgaris.

    PubMed

    Nakanishi, Koichi; Deuchi, Keiji

    2014-05-01

    In order to increase the value of freshwater algae as raw ingredients for health foods and feed for seawater-based farmed fish, we sought to breed high-chlorophyll halotolerant Chlorella with the objective of generating strains with both high chlorophyll concentrations (≥ 5%) and halotolerance (up to 1% NaCl). We used the Chlorella vulgaris K strain in our research institute culture collection and induced mutations with UV irradiation and acriflavine which is known to effect mutations of mitochondrial DNA that are associated with chlorophyll production. Screenings were conducted on seawater-based "For Chlorella spp." (FC) agar medium, and dark-green-colored colonies were visually selected by macroscopic inspection. We obtained a high-chlorophyll halotolerant strain (designated C. vulgaris M-207A7) that had a chlorophyll concentration of 6.7% (d.m.), a level at least three-fold higher than that of K strain. This isolate also exhibited a greater survival rate in seawater that of K strain.

  16. Optimization of pressurized liquid extraction of carotenoids and chlorophylls from Chlorella vulgaris.

    PubMed

    Cha, Kwang Hyun; Lee, Hee Ju; Koo, Song Yi; Song, Dae-Geun; Lee, Dong-Un; Pan, Cheol-Ho

    2010-01-27

    Pressurized liquid extraction (PLE) was applied to the extraction of carotenoids and chlorophylls from the green microalga Chlorella vulgaris. Four extraction techniques such as maceration (MAC), Soxhlet extraction (SOX), ultrasound assisted extraction (UAE), and PLE were compared, and both the extraction temperature (50, 105, and 160 degrees C) and the extraction time (8, 19, and 30 min), which are the two main factors for PLE, were optimized with a central composite design to obtain the highest extraction efficiency. The extraction solvent (90% ethanol/water) could adequately extract the functional components from C. vulgaris. PLE showed higher extraction efficiencies than MAC, SOX, and UAE. Temperature was the key parameter having the strongest influence on the extraction of carotenoids and chlorophylls from chlorella. In addition, high heat treatment (>110 degrees C) by PLE minimized the formation of pheophorbide a, a harmful chlorophyll derivative. These results indicate that PLE may be a useful extraction method for the simultaneous extraction of carotenoids and chlorophylls from C. vulgaris.

  17. Saline wastewater treatment by Chlorella vulgaris with simultaneous algal lipid accumulation triggered by nitrate deficiency.

    PubMed

    Shen, Qiao-Hui; Gong, Yu-Peng; Fang, Wen-Zhe; Bi, Zi-Cheng; Cheng, Li-Hua; Xu, Xin-Hua; Chen, Huan-Lin

    2015-10-01

    Chlorella vulgaris, a marine microalgae strain adaptable to 0-50 g L(-1) of salinity, was selected for studying the coupling system of saline wastewater treatment and lipid accumulation. The effect of total nitrogen (T N) concentration was investigated on algal growth, nutrients removal as well as lipid accumulation. The removal efficiencies of TN and total phosphorus (TP) were found to be 92.2-96.6% and over 99%, respectively, after a batch cultivation of 20 days. To illustrate the response of lipid accumulation to nutrients removal, C. vulgaris was further cultivated in the recycling experiment of tidal saline water within the photobioreactor. The lipid accumulation was triggered upon the almost depletion of nitrate (<5 mg L(-1)), till the final highest lipid content of 40%. The nitrogen conversion in the sequence of nitrate, nitrite, and then to ammonium in the effluents was finally integrated with previous discussions on metabolic pathways of algal cell under nitrogen deficiency.

  18. Power generation enhancement in novel microbial carbon capture cells with immobilized Chlorella vulgaris

    NASA Astrophysics Data System (ADS)

    Zhou, Minghua; He, Huanhuan; Jin, Tao; Wang, Hongyu

    2012-09-01

    With the increasing concerns for global climate change, a sustainable, efficient and renewable energy production from wastewater is imperative. In this study, a novel microbial carbon capture cell (MCC), is constructed for the first time by the introduction of immobilized microalgae (Chlorella vulgaris) into the cathode chamber of microbial fuel cells (MFCs) to fulfill the zero discharge of carbon dioxide. This process can achieve an 84.8% COD removal, and simultaneously the maximum power density can reach 2485.35 mW m-3 at a current density of 7.9 A m-3 and the Coulombic efficiency is 9.40%, which are 88% and 57.7% greater than that with suspended C. vulgaris, respectively. These enhancements in performance demonstrate the feasibility of an economical and effective approach for the simultaneous wastewater treatment, electricity generation and biodiesel production from microalgae.

  19. Harvesting freshwater Chlorella vulgaris with flocculant derived from spent brewer's yeast.

    PubMed

    Prochazkova, Gita; Kastanek, Petr; Branyik, Tomas

    2015-02-01

    One of the key bottlenecks of the economically viable production of low added value microalgal products (food supplements, feed, biofuels) is the harvesting of cells from diluted culture medium. The main goals of this work were to prepare a novel flocculation agent based on spent brewer's yeast, a brewery by-product, and to test its harvesting efficiency on freshwater Chlorella vulgaris in different environments. The yeast was first autolyzed/hydrolyzed and subsequently chemically modified with 2-chloro-N,N-diethylethylamine hydrochloride (DEAE). Second, optimal dosage of modified spent yeast (MSY) flocculant for harvesting C. vulgaris was determined in culture media of various compositions. It was found that the absence of phosphorus ions decreased (0.4 mg MSY/g biomass), while the presence of algogenic organic matter (AOM) increased (51 mg MSY/g biomass) the required dosage of flocculant as compared to complete mineral medium with phosphorus and without AOM (12 mg MSY/g biomass).

  20. Mutual facilitations of food waste treatment, microbial fuel cell bioelectricity generation and Chlorella vulgaris lipid production.

    PubMed

    Hou, Qingjie; Pei, Haiyan; Hu, Wenrong; Jiang, Liqun; Yu, Ze

    2016-03-01

    Food waste contains large amount of organic matter that may be troublesome for handing, storage and transportation. A microbial fuel cell (MFC) was successfully constructed with different inoculum densities of Chlorella vulgaris for promoting food waste treatment. Maximum COD removal efficiency was registered with 44% and 25 g CODL(-1)d(-1) of substrate degradation rate when inoculated with the optimal initial density (150 mg L(-1)) of C. vulgaris, which were 2.9 times and 3.1 times higher than that of the abiotic cathode. With the optimum inoculum density of C. vulgaris, the highest open circuit voltage, working voltage and power density of MFC were 260 mV, 170 mV and 19151 mW m(-3), respectively. Besides the high biodiesel quality, promoted by MFC stimulation the biomass productivity and highest total lipid content of C. vulgaris were 207 mg L(-1)d(-1) and 31%, which were roughly 2.7 times and 1.2 times higher than the control group.

  1. Cultivating Chlorella vulgaris and Scenedesmus quadricauda microalgae to degrade inorganic compounds and pesticides in water.

    PubMed

    Baglieri, Andrea; Sidella, Sarah; Barone, Valeria; Fragalà, Ferdinando; Silkina, Alla; Nègre, Michèle; Gennari, Mara

    2016-09-01

    This work evaluates the possibility of cultivating Scenedesmus quadricauda and Chlorella vulgaris microalgae in wastewater from the hydroponic cultivation of tomatoes with the aim of purifying the water. S. quadricauda and C. vulgaris were also used in purification tests carried out on water contaminated by the following active ingredients: metalaxyl, pyrimethanil, fenhexamid, iprodione, and triclopyr. Fifty-six days after the inoculum was placed, a reduction was found in the concentration of nitric nitrogen, ammonia nitrogen, and soluble and total phosphorus. The decrease was 99, 83, 94, and 94 %, respectively, for C. vulgaris and 99, 5, 88, and 89 %, respectively, for S. quadricauda. When the microalgae were present, all the agrochemicals tested were removed more quickly from the water than from the sterile control (BG11). The increase in the rate of degradation was in the order metalaxyl > fenhexamid > iprodione > triclopyr > pyrimethanil. It was demonstrated that there was a real degradation of fenhexamid, metalaxyl, triclopyr, and iprodione, while in the case of pyrimethanil, the active ingredient removed from the substrate was absorbed onto the cells of the microalgae. It was also found that the agrochemicals used in the tests had no significant effect on the growth of the two microalgae. The experiment highlighted the possibility of using cultivations of C. vulgaris and S. quadricauda as purification systems for agricultural wastewater which contains eutrophic inorganic compounds such as nitrates and phosphates and also different types of pesticides.

  2. The Bioconcentration and Degradation of Nonylphenol and Nonylphenol Polyethoxylates by Chlorella vulgaris

    PubMed Central

    Sun, Hong-Wen; Hu, Hong-Wei; Wang, Lei; Yang, Ying; Huang, Guo-Lan

    2014-01-01

    Nonylphenol polyethoxylates (NPnEOs), a major class of nonionic surfactants, can easily enter into aquatic environments through various pathways due to their wide applications, which leads to the extensive existence of their relative stable metabolites, namely nonylphenol (NP) and mono- to tri-ethoxylates. This study investigated the bioconcentration and degradation of NP and NPnEO oligomers (n = 1–12) by a green algae, Chlorella vulgaris. Experimental results showed that C. vulgaris can remove NP from water phase efficiently, and bioconcentration and degradation accounted for approximately half of its loss, respectively, with a 48 h BCF (bioconcentration factor) of 2.42 × 103. Moreover, C. vulgaris could concentrate and degrade NPnEOs, distribution profiles of the series homologues of the NPnEOs in algae and water phase were quite different from the initial homologue profile. The 48 h BCF of the NPnEO homologues increased with the length of the EO chain. Degradation extent of total NPnEOs by C. vulgaris was 95.7%, and only 1.1% remained in water phase, and the other 3.2% remained in the algal cells. The algae removed the NPnEOs mainly through degradation. Due to rapid degradation, concentrations of the long chain NPnEO homologous in both water (n ≥ 2) and the algal phase (n ≥ 5) was quite low at the end of a 48 h experiment. PMID:24445260

  3. Streptomycin affects the growth and photochemical activity of the alga Chlorella vulgaris.

    PubMed

    Perales-Vela, Hugo Virgilio; García, Roberto Velasco; Gómez-Juárez, Evelyn Alicia; Salcedo-Álvarez, Martha Ofelia; Cañizares-Villanueva, Rosa Olivia

    2016-10-01

    Antibiotics are increasingly being used in human and veterinary medicine, as well as pest control in agriculture. Recently, their emergence in the aquatic environment has become a global concern. The aim of this study was to evaluate the effect of streptomycin on growth and photosynthetic activity of Chlorella vulgaris after 72h exposure. We found that growth, photosynthetic activity and the content of the D1 protein of photosystem II decreased. Analysis of chlorophyll a fluorescence emission shows a reduction in the energy transfer between the antenna complex and reaction center. Also the activity of the oxygen evolution complex and electron flow between QA and QB were significantly reduced; in contrast, we found an increase in the reduction rate of the acceptor side of photosystem I. The foregoing can be attributed to the inhibition of the synthesis of the D1 protein and perhaps other coded chloroplast proteins that are part of the electron transport chain which are essential for the transformation of solar energy in the photosystems. We conclude that micromolar concentrations of streptomycin can affect growth and photosynthetic activity of Chlorella vulgaris. The accumulation of antibiotics in the environment can become an ecological problem for primary producers in the aquatic environment.

  4. Investigation of mixotrophic, heterotrophic, and autotrophic growth of Chlorella vulgaris under agricultural waste medium.

    PubMed

    Mohammad Mirzaie, M A; Kalbasi, M; Mousavi, S M; Ghobadian, B

    2016-01-01

    Growth of Chlorella vulgaris and its lipid production were investigated under autotrophic, heterotrophic, and mixotrophic conditions. Cheap agricultural waste molasses and corn steep liquor from industries were used as carbon and nitrogen sources, respectively. Chlorella vulgaris grew remarkably under this agricultural waste medium, which resulted in a reduction in the final cost of the biodiesel production. Maximum dry weight of 2.62 g L(-1) was obtained in mixotrophic growth with the highest lipid concentration of 0.86 g L(-1). These biomass and lipid concentrations were, respectively, 140% and 170% higher than autotrophic growth and 300% and 1200% higher than heterotrophic growth. In mixotrophic growth, independent or simultaneous occurrence of autotrophic and heterotrophic metabolisms was investigated. The growth of the microalgae was observed to take place first heterotrophically to a minimum substrate concentration with a little fraction in growth under autotrophic metabolism, and then the cells grew more autotrophically. It was found that mixotrophic growth was not a simple combination of heterotrophic and autotrophic growth.

  5. Cultivation of Chlorella vulgaris in Column Photobioreactor for Biomass Production and Lipid Accumulation.

    PubMed

    Wong, Y K; Ho, K C; Tsang, Y F; Wang, L; Yung, K K L

    2016-01-01

    Microalgae have been used as energy resources in recent decades to mitigate the global energy crisis. As the demand for pure microalgae strains for commercial use increases, designing an effective photobioreactor (PBR) for mass cultivation is important. Chlorella vulgaris, a local freshwater microalga, was used to study the algal biomass cultivation and lipid production using various PBR configurations (bubbling, air-lift, porous air-lift). The results show that a bubbling column design is a better choice for the cultivation of Chlorella vulgaris than an air-lift one. The highest biomass concentration in the bubbling PBR was 0.78 g/L while the air-lift PBR had a value of 0.09 g/L. Key operating parameters, including draft-tube length and bubbling flowrate, were then optimized based on biomass production and lipid yield. The highest lipid content was in the porous air-lift PBR and the air-lift PBR with shorter draft tube (35 cm) was also better than a longer one (50 cm) for algal cultivation, but the microalgae attachment on the inner tube of PBR always occurred. The highest biomass concentration could be produced under the highest gas flowrate of 2.7 L/min, whereas the lowest dry cell mass was under the lowest gas flowrate of 0.2 L/min.

  6. Effect of a hot water extract of Chlorella vulgaris on proliferation of IEC-6 cells.

    PubMed

    Song, Seo-Hyeon; Kim, In-Hye; Nam, Taek-Jeong

    2012-05-01

    Chlorella vulgaris, a unicellular microalgae, exerts various biological effects; however their effect on proliferation signaling pathways in normal cells has not been studied. We investigated the effect of hot water extracts of Chlorella vulgaris (CVE) on cell proliferation and related signaling pathways in rat intestinal epithelial cells (IEC-6). CVE increased the expression of insulin-like growth factor-I receptor (IGF-IR) and the phosphorylation of focal adhesion kinase (FAK) and Src. In addition, CVE induced activation of the mitogen-activated protein kinase (MAPK) and phosphatidylinositol 3-kinase (PI3K)/Akt pathways. We verified the increased phosphorylation of extracellular-signal-related kinase (ERK) and Akt and the increased expression of the PI3K regulatory subunit p85. CVE also influenced the canonical Wnt pathway through increased expression of the nuclear β-catenin, cyclin D1. Tyr-397 of FAK mediates interactions with Src homology 2 (SH2) domains in a number of other signaling proteins, including PI3K, PLC-γ, Shc, Grb7, Src and Nck2. Because CVE induced FAK activation, FAK may affect the Wnt pathway. Addition of a FAK inhibitor decreased the expression of nuclear β-catenin, cyclin D1 and c-myc, and increased the expression of cytosolic β-catenin. We conclude that CVE stimulated proliferation of IEC-6 cells via the MAPK, PI3K/Akt and canonical Wnt pathways, and that this affected the canonical Wnt pathway.

  7. Quantification of nutrient-replete growth rates in five-ion hyperspace for Chlorella vulgaris (Trebouxiophyceae) and Peridinium cinctum (Dinophyceae).

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effects of five ions, NO3-, PO43-, K+, Na+ and Cl- on growth rates and cell densities were quantified for Chlorella vulgaris (Chlorophycea) and Peridinium cinctum (Dinophycea) in batch cultures. A five dimensional experimental design, the five component mixture design projected across a total i...

  8. Chlorella vulgaris culture as a regulator of CO2 in a bioregenerative life support system

    NASA Astrophysics Data System (ADS)

    Li, Ming; Hu, Dawei; Liu, Hong; Hu, Enzhu; Xie, Beizhen; Tong, Ling

    2013-08-01

    It is the primary task for a bioregenerative life support system (BLSS) to maintain the stable concentrations of CO2 and O2. However, these concentrations could fluctuate based on various factors, such as the imbalance between respiration/assimilation quotients of the heterotrophic and autotrophic components. They can even be out of balance through catastrophic failure of higher plants in the emergency conditions. In this study, the feasibility of using unicellular Chlorella vulgaris of typically rapid growth as both “compensatory system” and “regulator” to control the balance of CO2 and O2 was analyzed in a closed ecosystem. For this purpose, a small closed ecosystem called integrative experimental system (IES) was established in our laboratory where we have been conducting multi-biological life support system experiments (MLSSE). The IES consists of a closed integrative cultivating system (CICS) and a plate photo-bioreactor. Four volunteers participated in the study for gas exchange by periodical breathing through a tube connected with the CICS. The plate photo-bioreactor was used to cultivate C. vulgaris. Results showed that the culture of C. vulgaris could be used in a situation of catastrophic failure of higher plant under the emergencies. And the productivity could recover itself to the original state in 3 to 5 days to protect the system till the higher plant was renewed. Besides, C. vulgaris could grow well and the productivity could be affected by the light intensity which could help to keep the balance of CO2 and O2 in the IES efficiently. Thus, C. vulgaris could be included in the design of a BLSS as a “compensatory system” in the emergency contingency and a “regulator” during the normal maintenance.

  9. The effect of cadmium on the growth and antioxidant response for freshwater algae Chlorella vulgaris.

    PubMed

    Cheng, Jinfeng; Qiu, Hongchen; Chang, Zhaoyang; Jiang, Zaimin; Yin, Wenke

    2016-01-01

    The objective of the present work was to evaluate the effect of exogenously applied cadmium on the physiological response of green algae Chlorella vulgaris. The study investigated the long-term effect (18 days) of cadmium on the levels of algae biomass, assimilation pigment composition, soluble protein, oxidative status (production of hydrogen peroxide and superoxide anion), antioxidant enzymes (such as superoxide dismutase, peroxidase, catalase and glutathione reductase enzyme) in C. vulgaris. The results showed that growth, the amount of chlorophyll a (Chl a), chlorophyll b (Chl b) and carotenoids gradually decreased with increasing cadmium over 18 days exposure. Cadmium at concentration of 7 mg L(-1) inhibited algal growth expressed as the number of cells. Our research found that C. vulgaris has a high tolerance to cadmium. Contents of chlorophylls (Chl a and Chl b) and carotenoids (Car) of C. vulgaris was significantly decline with rising concentration of cadmium (p < 0.05). The decrease of 54.04 and 93.37 % in Chl a, 60.65 and 74.32 % in Chl b, 50.00 and 71.88 % in total carotenoids was noticed following the treatment with 3 and 7 mg L(-1) cadmium doses compared with control treatment, respectively. Cadmium treatments caused a significant change in the physiological competence (calculated as chlorophyll a/b) which increased with increasing Cd(II) doses up to 1 mg L(-1) but decreased at 3 mg L(-1). While accumulation of soluble protein was enhanced by presence of cadmium, the treatment with cadmium at 3 and 7 mg L(-1) increased the concentration of soluble proteins by 88, 95.8 % in C. vulgaris, respectively. Moreover, low doses of cadmium stimulated enzymatic (superoxide dismutase, catalase and glutathione reductase) in C. vulgaris, The content of peroxidase increased with the increasing cadmium concentration, and had slightly decreased at the concentration of 7 mg L(-1), but was still higher than control group, which showed that cadmium

  10. Oxy-fuel combustion characteristics and kinetics of microalgae Chlorella vulgaris by thermogravimetric analysis.

    PubMed

    Chen, Chunxiang; Lu, Ziguang; Ma, Xiaoqian; Long, Jun; Peng, Yuning; Hu, Likun; Lu, Quan

    2013-09-01

    Oxy-fuel or O2/CO2 combustion technology was used to investigate the combustion of Chlorella vulgaris by thermogravimetric analysis (TGA). Oxy-fuel combustion occurs in an O2/CO2 atmosphere instead of an O2/N2 atmosphere and offers an alternative method of C. vulgaris preparation for biofuels processing. Our results show that three stages were observed during C. vulgaris combustion and the main combustion process occurred at the second stage. Compared with a 20%O2/80%N2 atmosphere, the mass loss rate at the DTG peaks (Rp) and the average reaction rate (Rv) in a 20%O2/80%CO2 atmosphere was lower, while the ignition temperature (TI) was higher. As oxygen concentration increases in an O2/CO2 atmosphere, Rp, Rv and the apparent activation energy (E) increases, while TI, the final temperature detected as mass stabilization (Tf) and the residue mass (Mr) decreases; As the heating rate (β) increases, TI, Tf and Rp increase, while Mr decreases.

  11. Alleviating CTAC and Flu combined pollution damage in Chlorella vulgaris by exogenous nitric oxide.

    PubMed

    Li, Qi; Liang, Zhijie; Ge, Fei; Xu, Yin; Yang, Liang; Zeng, Hui

    2014-02-01

    This study investigates the effect of sodium nitroprussiate (SNP), an exogenous NO-donor, on the joint toxicity of binary mixtures of cetyltrimethylammonium chloride (CTAC) and fluoranthene (Flu) (CTAC/Flu), which are representatives for surfactants and polycyclic aromatic hydrocarbons (PAHs) respectively, in a unicellular green alga Chlorella vulgaris (C. vulgaris). The results showed that the addition of low SNP (20μM) alleviated the CTAC/Flu combined pollution damage in C. vulgaris. Supplement of low SNP significantly increased the algae biomass, chlorophyll content, soluble protein content and the activities of superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) as compared to CTAC/Flu treatment alone. SNP also reduced the content of malondialdehyde (MDA) and the reactive oxygen species (ROS), as compared with CTAC/Flu treated alone. On the contrary, the above phenomena were reversed when high concentration of SNP (100μM) was added. Our study indicated that the damage of the joint action of surfactants and PAHs on hydrobios can be alleviated through protecting against oxidant substances and increasing the activity of antioxidant enzymes with an exogenous supply of NO in certain concentration range.

  12. Optimization of culture media for large-scale lutein production by heterotrophic Chlorella vulgaris.

    PubMed

    Jeon, Jin Young; Kwon, Ji-Sue; Kang, Soon Tae; Kim, Bo-Ra; Jung, Yuchul; Han, Jae Gap; Park, Joon Hyun; Hwang, Jae Kwan

    2014-01-01

    Lutein is a carotenoid with a purported role in protecting eyes from oxidative stress, particularly the high-energy photons of blue light. Statistical optimization was performed to growth media that supports a higher production of lutein by heterotrophically cultivated Chlorella vulgaris. The effect of media composition of C. vulgaris on lutein was examined using fractional factorial design (FFD) and central composite design (CCD). The results indicated that the presence of magnesium sulfate, EDTA-2Na, and trace metal solution significantly affected lutein production. The optimum concentrations for lutein production were found to be 0.34 g/L, 0.06 g/L, and 0.4 mL/L for MgSO4 ·7H2 O, EDTA-2Na, and trace metal solution, respectively. These values were validated using a 5-L jar fermenter. Lutein concentration was increased by almost 80% (139.64 ± 12.88 mg/L to 252.75 ± 12.92 mg/L) after 4 days. Moreover, the lutein concentration was not reduced as the cultivation was scaled up to 25,000 L (260.55 ± 3.23 mg/L) and 240,000 L (263.13 ± 2.72 mg/L). These observations suggest C. vulgaris as a potential lutein source.

  13. Proteomic analysis of Chlorella vulgaris: Potential targets for enhanced lipid accumulation

    SciTech Connect

    Guarnieri, Michael T.; Nag, Ambarish; Yang, Shihui; Pienkos, Philip T.

    2013-11-01

    Oleaginous microalgae are capable of producing large quantities of fatty acids and triacylglycerides. As such, they are promising feedstocks for the production of biofuels and bioproducts. Genetic strain-engineering strategies offer a means to accelerate the commercialization of algal biofuels by improving the rate and total accumulation of microalgal lipids. However, the industrial potential of these organisms remains to be met, largely due to the incomplete knowledgebase surrounding the mechanisms governing the induction of algal lipid biosynthesis. Such strategies require further elucidation of genes and gene products controlling algal lipid accumulation. In this study, we have set out to examine these mechanisms and identify novel strain-engineering targets in the oleaginous microalga, Chlorella vulgaris. Comparative shotgun proteomic analyses have identified a number of novel targets, including previously unidentified transcription factors and proteins involved in cell signaling and cell cycle regulation. These results lay the foundation for strain-improvement strategies and demonstrate the power of translational proteomic analysis.

  14. First evidence of bioflocculant from Shinella albus with flocculation activity on harvesting of Chlorella vulgaris biomass.

    PubMed

    Li, Yi; Xu, Yanting; Liu, Lei; Jiang, Xiaobing; Zhang, Kun; Zheng, Tianling; Wang, Hailei

    2016-10-01

    Bioflocculant from Shinella albus xn-1 could be used to harvest energy-producing microalga Chlorella vulgaris biomass for the first time. In this study, we investigated the flocculation activity and mode of strain xn-1, the characteristics of bioflocculant, the effect of flocculation conditions and optimized the flocculation efficiency. The results indicated that strain xn-1 exhibited flocculation activity through secreting bioflocculant; the bioflocculant with high thermal stability, pH stability and low molecular weight was proved to be not protein and polysaccharide, and flocculation active component was confirmed to contain triple bond and cumulated double bonds; algal pH, temperature and metal ions showed great impacts on the flocculation efficiency of bioflocculant; the maximum flocculation activity of bioflocculant reached 85.65% after the response surface optimization. According to the results, the bioflocculant from S. albus xn-1 could be a good potential in applications for high-efficiency harvesting of microalgae.

  15. Photosynthetic light reactions increase total lipid accumulation in carbon-supplemented batch cultures of Chlorella vulgaris.

    PubMed

    Woodworth, Benjamin D; Mead, Rebecca L; Nichols, Courtney N; Kolling, Derrick R J

    2015-03-01

    Microalgae are an attractive biofuel feedstock because of their high lipid to biomass ratios, lipid compositions that are suitable for biodiesel production, and the ability to grow on varied carbon sources. While algae can grow autotrophically, supplying an exogenous carbon source can increase growth rates and allow heterotrophic growth in the absence of light. Time course analyses of dextrose-supplemented Chlorella vulgaris batch cultures demonstrate that light availability directly influences growth rate, chlorophyll production, and total lipid accumulation. Parallel photomixotrophic and heterotrophic cultures grown to stationary phase reached the same amount of biomass, but total lipid content was higher for algae grown in the presence of light (an average of 1.90 mg/mL vs. 0.77 mg/mL over 5 days of stationary phase growth).

  16. Isolation and purification of lutein from the microalga Chlorella vulgaris by extraction after saponification.

    PubMed

    Li, Hua-Bin; Jiang, Yue; Chen, Feng

    2002-02-27

    A simple and efficient method for the isolation and purification of lutein from the microalga Chlorella vulgaris was developed. Crude lutein was obtained by extraction with dichloromethane from the microalga after saponification. Partition values of lutein in the two-phase system of ethanol-water-dichloromethane at different ratios were measured by HPLC so as to assist the determination of an appropriate condition for washing water-soluble impurities in the crude lutein. Partition values of lutein in another two-phase system of ethanol-water-hexane at different ratios were also measured by HPLC for determining the condition for removing fat-soluble impurities. The water-soluble impurities in the crude lutein were removed by washing with 30% aqueous ethanol, and the fat-soluble impurities were removed by extraction with hexane. The final purity of lutein obtained was 90-98%, and the yield was 85-91%.

  17. Gasification kinetics of raw and wet-torrefied microalgae Chlorella vulgaris ESP-31 in carbon dioxide.

    PubMed

    Bach, Quang-Vu; Chen, Wei-Hsin; Sheen, Herng-Kuang; Chang, Jo-Shu

    2017-03-27

    This study aims at investigating the gasification behavior and kinetics of microalga Chlorella vulgaris ESP-31 before and after wet torrefaction. The raw and wet-torrefied microalgae were first gasified in a thermogravimetric analyzer under a continuous CO2 flow. Thereafter, the obtained thermogravimetric data were modeled for kinetic study, employing a seven-parallel-reaction mechanism. The decomposition of the microalgae in CO2 shows two reactive stages: devolatilization with two peaks and gasification with a peak accompanied by a shoulder, and the thermal decomposition of components in the samples can be clearly identified. Increasing wet torrefaction temperature lowers the height of the major devolatilization peak but enhances the height of the minor one. Moreover, the kinetic evaluation reveals that wet torrefaction affects most of the kinetic parameters of the microalgal components. Furthermore, wet torrefaction temperature influences the kinetic parameters of carbohydrate and lipid, but not on those of protein, "others", and chars.

  18. Production of algal biomass (Chlorella vulgaris) using sediment microbial fuel cells.

    PubMed

    Jeon, Hyeon Jin; Seo, Kyu-won; Lee, Sang Hyun; Yang, Yung-Hun; Kumaran, Rangarajulu Senthil; Kim, Sunghyun; Hong, Seok Won; Choi, Yong Su; Kim, Hyung Joo

    2012-04-01

    In this study, a novel algal biomass production method using a sediment microbial fuel cell (SMFC) system was assessed. Under the experimental conditions, CO(2) generation from the SMFC and its rate of increase were found to be dependent on the current generated from the SMFC. However, the CH(4) production rate from the SMFC was inhibited by the generation of current. When Chlorella vulgaris was inoculated into the cathode compartment of the SMFC and current was generated under 10 Ω resistance, biomass production from the anode compartment was observed to be closely associated with the rate of current generation from the SMFC. The experimental results demonstrate that 420 mg/L of algae (dry cell weight) was produced when the current from the SMFC reached 48.5 mA/m(2). Therefore, SMFC could provide a means for producing algal biomass via CO(2) generated by the oxidation of organics upon current generation.

  19. Role of transparent exopolymeric particles in membrane fouling: Chlorella vulgaris broth filtration.

    PubMed

    Discart, V; Bilad, M R; Vandamme, D; Foubert, I; Muylaert, K; Vankelecom, I F J

    2013-02-01

    Recent reports show strong evidence for the involvement of transparent exopolymer particles (TEPs), mainly produced by microalgae in natural environments, in membrane fouling in a wide range of membrane filtration processes. The objective of this study is to fundamentally investigate the direct role of TEPs on membrane fouling by using different Chlorella vulgaris broth solutions and different fractions of such broth (the soluble and bound fractions, the cells separated from these fractions and the cells with their bound sugars, separated from the soluble fraction) as filtration feed. The relation between the feed properties and their filterability over three membranes was determined. Scanning electron microscopy and light microscopy showed that the foulant types differed for each broth fraction and confirmed the role of TEPs in the fouling of microfiltration membranes. In addition, this study contributes to the role of TEPs in the filtration of microalgae cultivated for commercial reasons.

  20. Effective harvesting of the microalgae Chlorella vulgaris via flocculation-flotation with bioflocculant.

    PubMed

    Lei, Xueqian; Chen, Yao; Shao, Zongze; Chen, Zhangran; Li, Yi; Zhu, Hong; Zhang, Jingyan; Zheng, Wei; Zheng, Tianling

    2015-12-01

    In this study, bioflocculant from Cobetia marina L03 could be used for effective harvesting of the microalgae Chlorella vulgaris via flocculation-flotation. A flotation efficiency of 92.7% was observed when 20 mg L(-1) bioflocculant was tested for flocculating the microalgal cells with 5mM CaCl2. The bioflocculant was stable at wide ranges of pH and temperature, which is advantageous for its application under various conditions. Chemical analysis of the bioflocculant indicated that it is composed of 31.6% total sugar and 0.2% protein (w/w). This bioflocculant has potential for the high-efficiency harvesting of microalgae and may be useful in reducing one of the barriers to microalgal biofuel production.

  1. Effect of moderate static electric field on the growth and metabolism of Chlorella vulgaris.

    PubMed

    Nezammahalleh, Hassan; Ghanati, Faezeh; Adams, Thomas A; Nosrati, Mohsen; Shojaosadati, Seyed Abbas

    2016-10-01

    An electric field (EF) generator device was fabricated and applied to the treatment of Chlorella vulgaris ISC33 at three distinct concentrations before cultivation. The EF of moderate intensity (2.7kVcm(-1)) has a hormetic effect on algal growth. The highest growth stimulation of 51% was observed after 50min treatment of 0.4gL(-1) algal suspension. The influence of EF on the system was then studied from both theoretical and experimental perspectives. The growth rate increased with treatment time up to a maximum because of improved membrane permeability, and then declined afterwards due to peroxide accumulation in the medium. The contents of chlorophylls, carotenoids, soluble carbohydrates, lipids, and proteins were also measured to understand possible changes on algal metabolism. The EF treatment of algal suspension has no observable effect on the cell metabolism while both algal growth and metabolism was significantly affected by the inoculum size.

  2. Optimising the bioreceptivity of porous glass tiles based on colonization by the alga Chlorella vulgaris.

    PubMed

    Ferrándiz-Mas, V; Bond, T; Zhang, Z; Melchiorri, J; Cheeseman, C R

    2016-09-01

    Green façades on buildings can mitigate greenhouse gas emissions. An option to obtain green facades is through the natural colonisation of construction materials. This can be achieved by engineering bioreceptive materials. Bioreceptivity is the susceptibility of a material to be colonised by living organisms. The aim of this research was to develop tiles made by sintering granular waste glass that were optimised for bioreceptivity of organisms capable of photosynthesis. Tiles were produced by pressing recycled soda-lime glass with a controlled particle size distribution and sintering compacted samples at temperatures between 680 and 740°C. The primary bioreceptivity of the tiles was evaluated by quantifying colonisation by the algae Chlorella vulgaris (C. vulgaris), which was selected as a model photosynthetic micro-organism. Concentrations of C. vulgaris were measured using chlorophyll-a extraction. Relationships between bioreceptivity and the properties of the porous glass tile, including porosity, sorptivity, translucency and pH are reported. Capillary porosity and water sorptivity were the key factors influencing the bioreceptivity of porous glass. Maximum C. vulgaris growth and colonisation was obtained for tiles sintered at 700°C, with chlorophyll-a concentrations reaching up to 11.1±0.4μg/cm(2) of tile. Bioreceptivity was positively correlated with sorptivity and porosity and negatively correlated with light transmittance. The research demonstrates that the microstructure of porous glass, determined by the processing conditions, significantly influences bioreceptivity. Porous glass tiles with high bioreceptivity that are colonised by photosynthetic algae have the potential to form carbon-negative façades for buildings and green infrastructure.

  3. Single and mixture toxicity of pharmaceuticals and chlorophenols to freshwater algae Chlorella vulgaris.

    PubMed

    Geiger, Elisabeth; Hornek-Gausterer, Romana; Saçan, Melek Türker

    2016-07-01

    Organisms in the aquatic environment are exposed to a variety of substances of numerous chemical classes. The unintentional co-occurrence of pharmaceuticals and other contaminants of emerging concern may pose risk to non-target organisms. In this study, individual and binary mixture toxicity experiments of selected pharmaceuticals (ibuprofen and ciprofloxacin) and chlorophenols (2.4-dichlorophenol (2,4-DCP) and 3-chlorophenol (3-CP)) have been performed with freshwater algae Chlorella vulgaris. All experiments have been carried out according to the 96-h algal growth inhibition test OECD No. 201. Binary mixture tests were conducted using proportions of the respective IC50s in terms of toxic unit (TU). The mixture concentration-response curve was compared to predicted effects based on both the concentration addition (CA) and the independent action (IA) model. Additionally, the Combination Index (CI)-isobologram equation method was used to assess toxicological interactions of the binary mixtures. All substances individually tested had a significant effect on C. vulgaris population density and revealed IC50 values <100mgL(-1) after exposure period of 96-h. The toxic ranking of these four compounds to C. vulgaris was 2,4-DCP>ciprofloxacin>3-CP>ibuprofen. Generally, it can be concluded from this study that toxic mixture effects of all tested chemicals to C. vulgaris are higher than the individual effect of each mixture component. It could be demonstrated that IC50 values of the tested mixtures predominately lead to additive effects. The CA model is appropriate to estimate mixture toxicity, while the IA model tends to underestimate the joint effect. The CI-isobologram equation method predicted the mixtures accurately and elicited synergism at low effect levels for the majority of tested combinations.

  4. Using oxidized liquid and solid human waste as nutrients for Chlorella vulgaris and cyanobacterium Oscillatoria deflexa

    NASA Astrophysics Data System (ADS)

    Trifonov, Sergey V.; Kalacheva, Galina; Tirranen, Lyalya; Gribovskaya, Iliada

    At stationary terrestrial and space stations with closed and partially closed substance exchange not only plants, but also algae can regenerate atmosphere. Their biomass can be used for feeding Daphnia and Moina species, which, in their turn, serve as food for fish. In addition, it is possible to use algae for production of biological fuel. We suggested two methods of human waste mineralization: dry (evaporation with subsequent incineration in a muffle furnace) and wet (oxidation in a reactor using hydrogen peroxide). The research task was to prepare nutrient media for green alga Chlorella vulgaris and cyanobacterium Oscillatoria deflexa using liquid human waste mineralized by dry method, and to prepare media for chlorella on the basis of 1) liquid and 2) liquid and solid human waste mineralized by wet method. The algae were grown in batch culture in a climate chamber with the following parameters: illumination 7 klx, temperature 27-30 (°) C, culture density 1-2 g/l of dry weight. The control for chlorella was Tamiya medium, pH-5, and for oscillstoria — Zarrouk medium, pH-10. Maximum permissible concentrations of NaCl, Cl, urea (NH _{2}) _{2}CO, and native urine were established for algae. Missing ingredients (such as salts and acids) for experimental nutrient media were determined: their addition made it possible to obtain the biomass production not less than that in the control. The estimation was given of the mineral and biochemical composition of algae grown on experimental media. Microbiological test revealed absence of foreign microbial flora in experimental cultures.

  5. Inhibition of Pro-inflammatory Mediators and Cytokines by Chlorella Vulgaris Extracts

    PubMed Central

    Sibi, G.; Rabina, Santa

    2016-01-01

    Objective: The aim of this study was to determine the in vitro anti-inflammatory activities of solvent fractions from Chlorella vulgaris by inhibiting the production of pro-inflammatory mediators and cytokines. Methods: Methanolic extracts (80%) of C. vulgaris were prepared and partitioned with solvents of increasing polarity viz., n-hexane, chloroform, ethanol, and water. Various concentrations of the fractions were tested for cytotoxicity in RAW 264.7 cells using 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay, and the concentrations inducing cell growth inhibition by about 50% (IC50) were chosen for further studies. Lipopolysaccharide (LPS) stimulated RAW 264.7 cells were treated with varying concentrations of C. vulgaris fractions and examined for its effects on nitric oxide (NO) production by Griess assay. The release of prostaglandin E2 (PGE2), tumor necrosis factor-α (TNF-α), and interleukin 6 (IL-6) were quantified using enzyme-linked immunosorbent assay using Celecoxib and polymyxin B as positive controls. Results: MTT assay revealed all the solvent fractions that inhibited cell growth in a dose-dependent manner. Of all the extracts, 80% methanolic extract exhibited the strongest anti-inflammatory activity by inhibiting NO production (P < 0.01), PGE2 (P < 0.05), TNF-α, and IL-6 (P < 0.001) release in LPS induced RAW 264.7 cells. Both hexane and chloroform fractions recorded a significant (P < 0.05) and dose-dependent inhibition of LPS induced inflammatory mediators and cytokines in vitro. The anti-inflammatory effect of ethanol and aqueous extracts was not significant in the study. Conclusion: The significant inhibition of inflammatory mediators and cytokines by fractions from C. vulgaris suggests that this microalga would be a potential source of developing anti-inflammatory agents and a good alternate for conventional steroidal and nonsteroidal anti-inflammatory drugs. SUMMARY C. vulgaris extracts have potential anti

  6. Cultivation of Chlorella vulgaris in wastewater with waste glycerol: Strategies for improving nutrients removal and enhancing lipid production.

    PubMed

    Ma, Xiaochen; Zheng, Hongli; Addy, Min; Anderson, Erik; Liu, Yuhuan; Chen, Paul; Ruan, Roger

    2016-05-01

    To improve nutrients removal from wastewater and enhance lipid production, cultivation of Chlorella vulgaris in wastewater with waste glycerol generated from biodiesel production using scum derived oil as feedstock was studied. The results showed that nutrients removal was improved and lipid production of C. vulgaris was enhanced with the addition of waste glycerol into wastewater to balance its C/N ratio. The optimal concentration of the pretreated glycerol for C. vulgaris was 10gL(-1) with biomass concentration of 2.92gL(-1), lipid productivity of 163mgL(-1)d(-1), and the removal of 100% ammonia and 95% of total nitrogen. Alkaline conditions prompted cell growth and lipid accumulation of C. vulgaris while stimulating nutrients removal. The application of the integration process can lower both wastewater treatment and biofuel feedstock costs.

  7. Selenium Accumulation in Unicellular Green Alga Chlorella vulgaris and Its Effects on Antioxidant Enzymes and Content of Photosynthetic Pigments

    PubMed Central

    Sun, Xian; Zhong, Yu; Huang, Zhi; Yang, Yufeng

    2014-01-01

    The aim of the present study was to investigate selenite effects in the unicellular green algae Chlorella vulgaris as a primary producer and the relationship with intracellular bioaccumulation. The effects of selenite were evaluated by measuring the effect of different selenite concentrations on algal growth during a 144 h exposure period. It was found that lower Se concentrations (≤75 mg L−1) positively promoted C. vulgaris growth and acted as antioxidant by inhibiting lipid peroxidation (LPO) and intracellular reactive oxygen species (ROS). The antioxidative effect was associated with an increase in guaiacol peroxidase (GPX), catalase (CAT), superoxide dismutase (SOD) and photosynthetic pigments. Meanwhile, significant increase in the cell growth rate and organic Se content was also detected in the algae. In contrast, these changes were opposite in C. vulgaris exposed to Se higher than 100 mg L−1. The antioxidation and toxicity appeared to be correlated to Se bioaccumulation, which suggests the appropriate concentration of Se in the media accumulation of C. vulgaris should be 75 mg L−1. Taken together, C. vulgaris possesses tolerance to Se, and Se-Chlorella could be developed as antioxidative food for aquaculture and human health. PMID:25375113

  8. Selenium accumulation in unicellular green alga Chlorella vulgaris and its effects on antioxidant enzymes and content of photosynthetic pigments.

    PubMed

    Sun, Xian; Zhong, Yu; Huang, Zhi; Yang, Yufeng

    2014-01-01

    The aim of the present study was to investigate selenite effects in the unicellular green algae Chlorella vulgaris as a primary producer and the relationship with intracellular bioaccumulation. The effects of selenite were evaluated by measuring the effect of different selenite concentrations on algal growth during a 144 h exposure period. It was found that lower Se concentrations (≤ 75 mg L(-1)) positively promoted C. vulgaris growth and acted as antioxidant by inhibiting lipid peroxidation (LPO) and intracellular reactive oxygen species (ROS). The antioxidative effect was associated with an increase in guaiacol peroxidase (GPX), catalase (CAT), superoxide dismutase (SOD) and photosynthetic pigments. Meanwhile, significant increase in the cell growth rate and organic Se content was also detected in the algae. In contrast, these changes were opposite in C. vulgaris exposed to Se higher than 100 mg L-1. The antioxidation and toxicity appeared to be correlated to Se bioaccumulation, which suggests the appropriate concentration of Se in the media accumulation of C. vulgaris should be 75 mg L-1. Taken together, C. vulgaris possesses tolerance to Se, and Se-Chlorella could be developed as antioxidative food for aquaculture and human health.

  9. Optimization of continuous lipid extraction from Chlorella vulgaris by CO₂-expanded methanol for biodiesel production.

    PubMed

    Yang, Yi-Hung; Klinthong, Worasaung; Tan, Chung-Sung

    2015-12-01

    CO2-expanded methanol (CXM) was used to extract lipids from the microalgae Chlorella vulgaris (a total lipid content of 20.7% was determined by Soxhlet extraction with methanol at 373 K for 96 h) in a continuous mode. The CXM was found to be a superior solvent to methanol, ethanol, pressurized methanol and ethanol, and CO2-expanded ethanol for lipid extraction. The effects of operation variables including temperature, pressure and CO2 flow rate on extraction performance were examined using the response surface and contour plot methodologies. The optimal operating conditions were at a pressure of 5.5 MPa, a temperature of 358 K, a methanol flow rate of 1 mL/min and a CO2 flow rate of 3.0 mL/min, providing an extracted lipid yield of 84.8 wt% over an extraction period of 30 min. Compared with propane methanol mixture, CXM was safer and more energy efficient for lipid extraction from C. vulgaris.

  10. Size-dependent ecotoxicity of barium titanate particles: the case of Chlorella vulgaris green algae.

    PubMed

    Polonini, Hudson C; Brandão, Humberto M; Raposo, Nádia R B; Brandão, Marcos Antônio F; Mouton, Ludovic; Couté, Alain; Yéprémian, Claude; Sivry, Yann; Brayner, Roberta

    2015-05-01

    Studies have been demonstrating that smaller particles can lead to unexpected and diverse ecotoxicological effects when compared to those caused by the bulk material. In this study, the chemical composition, size and shape, state of dispersion, and surface's charge, area and physicochemistry of micro (BT MP) and nano barium titanate (BT NP) were determined. Green algae Chlorella vulgaris grown in Bold's Basal (BB) medium or Seine River water (SRW) was used as biological indicator to assess their aquatic toxicology. Responses such as growth inhibition, cell viability, superoxide dismutase (SOD) activity, adenosine-5-triphosphate (ATP) content and photosynthetic activity were evaluated. Tetragonal BT (~170 nm, 3.24 m(2) g(-1) surface area) and cubic BT (~60 nm, 16.60 m(2) g(-1)) particles were negative, poorly dispersed, and readily aggregated. BT has a statistically significant effect on C. vulgaris growth since the lower concentration tested (1 ppm), what seems to be mediated by induced oxidative stress caused by the particles (increased SOD activity and decreased photosynthetic efficiency and intracellular ATP content). The toxic effects were more pronounced when the algae was grown in SRW. Size does not seem to be an issue influencing the toxicity in BT particles toxicity since micro- and nano-particles produced significant effects on algae growth.

  11. Rapid induction of lipid droplets in Chlamydomonas reinhardtii and Chlorella vulgaris by Brefeldin A.

    PubMed

    Kim, Sangwoo; Kim, Hanul; Ko, Donghwi; Yamaoka, Yasuyo; Otsuru, Masumi; Kawai-Yamada, Maki; Ishikawa, Toshiki; Oh, Hee-Mock; Nishida, Ikuo; Li-Beisson, Yonghua; Lee, Youngsook

    2013-01-01

    Algal lipids are the focus of intensive research because they are potential sources of biodiesel. However, most algae produce neutral lipids only under stress conditions. Here, we report that treatment with Brefeldin A (BFA), a chemical inducer of ER stress, rapidly triggers lipid droplet (LD) formation in two different microalgal species, Chlamydomonas reinhardtii and Chlorella vulgaris. LD staining using Nile red revealed that BFA-treated algal cells exhibited many more fluorescent bodies than control cells. Lipid analyses based on thin layer chromatography and gas chromatography revealed that the additional lipids formed upon BFA treatment were mainly triacylglycerols (TAGs). The increase in TAG accumulation was accompanied by a decrease in the betaine lipid diacylglyceryl N,N,N-trimethylhomoserine (DGTS), a major component of the extraplastidic membrane lipids in Chlamydomonas, suggesting that at least some of the TAGs were assembled from the degradation products of membrane lipids. Interestingly, BFA induced TAG accumulation in the Chlamydomonas cells regardless of the presence or absence of an acetate or nitrogen source in the medium. This effect of BFA in Chlamydomonas cells seems to be due to BFA-induced ER stress, as supported by the induction of three homologs of ER stress marker genes by the drug. Together, these results suggest that ER stress rapidly triggers TAG accumulation in two green microalgae, C. reinhardtii and C. vulgaris. A further investigation of the link between ER stress and TAG synthesis may yield an efficient means of producing biofuel from algae.

  12. The growth response of the green alga Chlorella vulgaris to combined divalent cation exposure.

    PubMed

    Rachlin, J W; Grosso, A

    1993-01-01

    Using the growth response of the green alga Chlorella vulgaris as a model system, the effects of combinations of the environmentally active cations Cd, Co, and Cu were evaluated. The 96-h static EC50 for these cations to C. vulgaris were, respectively, 0.89 microM, 9.0 microM, and 2.8 microM, yielding a toxicity series such that Cd > Cu > Co. The cation combinations of Cd + Cu, and Cu + Co acted synergistically, while Cd + Co, and the tri-metallic combination Cd + Cu + Co resulted in antagonistic interactions. Examination of these toxic combinations at 24, 48, 72, and 96 h indicate that the cellular response is not a uniform one. Failure of energy dispersive X-ray spectrophotometric analysis to demonstrate any intracellular incorporation of these cations (except for a weak cytoplasmic Cu peak at the 8.0 KEV position) suggests that the toxic actions of these cations at EC50 concentrations are exerted at the level of the plasma membrane.

  13. Metal distributions in complexes with Chlorella vulgaris in seawater and wastewater

    SciTech Connect

    Pascucci, P.R.; Kowalak, A.D.

    1999-10-01

    Divalent cadmium (Cd), copper (Cu), iron (Fe), nickel (Ni), lead (Pb), and zinc (Zn) simultaneous complexes with an algal biomass Chlorella vulgaris were studied for bioremediation purposes in various aqueous media: distilled-deionized water (DDIW), seawater, nuclear-reactor pool water, and process wastewater. Reactions were monitored using various dry masses of algae at constant temperature and constant metal concentrations for reaction times ranging from 0 to 150 minutes. Complexes occurred within 30 minutes and reached a steady state after 80 to 120 minutes. Distribution constants (K{prime}{sub d}) were calculated for the complexes and relative orders of K{prime}{sub d} were reported. The K{prime}{sub d} are used to evaluate relative efficiency of metal remediation from waters. Lead, Cu, and Ni complexes had the greatest K{prime}{sub d} values and those metals were most efficiently removed from these waters. Zinc and Fe formed the most labile complexes. The order of K{prime}{sub d} values for complexes in DDIW was Pb > Cu > Cd > Zn, then Cu > Cd > Zn in seawater, Cd > Cu > Zn in reactor pool water, and Ni > Cd > Cu > Zn > Fe in wastewater. C. vulgaris biomass may potentially be used as an alternative to traditional water treatment methods for simultaneous extraction of metals from seawater, process wastewater, or drinking water.

  14. Construction and operation of microbial fuel cell with Chlorella vulgaris biocathode for electricity generation.

    PubMed

    Wu, Xia-yuan; Song, Tian-shun; Zhu, Xu-jun; Wei, Ping; Zhou, Charles C

    2013-12-01

    In this study, a modified microbial fuel cell (MFC) with a tubular photobioreactor (PHB) configuration as a cathode compartment was constructed by introducing Chlorella vulgaris to the cathode chamber used to generate oxygen in situ. Two types of cathode materials and light/dark cycles were used to test the effect on MFC with algae biocathode. Results showed that the use of algae is an effective approach because these organisms can act as efficient in situ oxygenators, thereby facilitating the cathodic reaction. Dissolved oxygen and voltage output displayed a clear light positive response and were drastically enhanced compared with the abiotic cathode. In particular, carbon paper-coated Pt used as a cathode electrode increased voltage output at a higher extent than carbon felt used as an electrode. The maximum power density of 24.4 mW/m(2) was obtained from the MFC with algae biocathode which utilized the carbon paper-coated Pt as the cathode electrode under intermittent illumination. This density was 2.8 times higher than that of the abiotic cathode. Continuous illumination shortened the algal lifetime. These results demonstrated that intermittent illumination and cathode material-coated catalyst are beneficial to a more efficient and prolonged operation of MFC with C. vulgaris biocathode.

  15. Construction and operation of microbial fuel cell with Chlorella vulgaris biocathode for electricity generation.

    PubMed

    Wu, Xia-yuan; Song, Tian-shun; Zhu, Xu-jun; Wei, Ping; Zhou, Charles C

    2013-12-01

    In this study, a modified microbial fuel cell (MFC) with a tubular photobioreactor (PHB) configuration as a cathode compartment was constructed by introducing Chlorella vulgaris to the cathode chamber used to generate oxygen in situ. Two types of cathode materials and light/dark cycles were used to test the effect on MFC with algae biocathode. Results showed that the use of algae is an effective approach because these organisms can act as efficient in situ oxygenators, thereby facilitating the cathodic reaction. Dissolved oxygen and voltage output displayed a clear light positive response and were drastically enhanced compared with the abiotic cathode. In particular, carbon paper-coated Pt used as a cathode electrode increased voltage output at a higher extent than carbon felt used as an electrode. The maximum power density of 24.4 mW/m2 was obtained from the MFC with algae biocathode which utilized the carbon paper-coated Pt as the cathode electrode under intermittent illumination. This density was 2.8 times higher than that of the abiotic cathode. Continuous illumination shortened the algal lifetime. These results demonstrated that intermittent illumination and cathode material-coated catalyst are beneficial to a more efficient and prolonged operation of MFC with C. vulgaris biocathode.

  16. Biogenic hydrogen and methane production from Chlorella vulgaris and Dunaliella tertiolecta biomass

    PubMed Central

    2011-01-01

    Background Microalgae are a promising feedstock for biofuel and bioenergy production due to their high photosynthetic efficiencies, high growth rates and no need for external organic carbon supply. In this study, utilization of Chlorella vulgaris (a fresh water microalga) and Dunaliella tertiolecta (a marine microalga) biomass was tested as a feedstock for anaerobic H2 and CH4 production. Results Anaerobic serum bottle assays were conducted at 37°C with enrichment cultures derived from municipal anaerobic digester sludge. Low levels of H2 were produced by anaerobic enrichment cultures, but H2 was subsequently consumed even in the presence of 2-bromoethanesulfonic acid, an inhibitor of methanogens. Without inoculation, algal biomass still produced H2 due to the activities of satellite bacteria associated with algal cultures. CH4 was produced from both types of biomass with anaerobic enrichments. Polymerase chain reaction-denaturing gradient gel electrophoresis profiling indicated the presence of H2-producing and H2-consuming bacteria in the anaerobic enrichment cultures and the presence of H2-producing bacteria among the satellite bacteria in both sources of algal biomass. Conclusions H2 production by the satellite bacteria was comparable from D. tertiolecta (12.6 ml H2/g volatile solids (VS)) and from C. vulgaris (10.8 ml H2/g VS), whereas CH4 production was significantly higher from C. vulgaris (286 ml/g VS) than from D. tertiolecta (24 ml/g VS). The high salinity of the D. tertiolecta slurry, prohibitive to methanogens, was the probable reason for lower CH4 production. PMID:21943287

  17. Cyanobacterium Microcystis aeruginosa response to pentachlorophenol and comparison with that of the microalga Chlorella vulgaris.

    PubMed

    de Morais, Paulo; Stoichev, Teodor; Basto, M Clara P; Ramos, V; Vasconcelos, V M; Vasconcelos, M Teresa S D

    2014-04-01

    Pentachlorophenol (PCP) effects on a strain of the cyanobacterium Microcystis aeruginosa were investigated at laboratory scale. This is the first systematic ecotoxicity study of the effects of PCP on an aquatic cyanobacterium. The microalga Chlorella vulgaris was studied in the same conditions as the cyanobacterium, in order to compare the PCP toxicity and its removal by the species. The cells were exposed to environmental levels of PCP during 10 days, in Fraquil culture medium, at nominal concentrations from 0.01 to 1000 μg L(-1), to the cyanobacterium, and 0.01 to 5000 μg L(-1), to the microalga. Growth was assessed by area under growth curve (AUC, optical density vs time) and chlorophyll a content (chla). The toxicity profiles of the two species were very different. The calculated effective concentrations EC20 and EC50 were much lower to M. aeruginosa, and its growth inhibition expressed by chla was concentration-dependent while by AUC was not concentration-dependent. The cells might continue to divide even with lower levels of chla. The number of C. vulgaris cells decreased with the PCP concentration without major impact on the chla. The effect of PCP on M. aeruginosa is hormetic: every concentration studied was toxic except 1 μg L(-1), which promoted its growth. The legal limit of PCP set by the European Union for surface waters (1 μg L(-1)) should be reconsidered since a toxic cyanobacteria bloom might occur. The study of the removal of PCP from the culture medium by the two species is an additional novelty of this work. M. aeruginosa could remove part of the PCP from the medium, at concentrations where toxic effects were observed, while C. vulgaris stabilized it.

  18. Biological CO2 fixation using Chlorella vulgaris and its thermal characteristics through thermogravimetric analysis.

    PubMed

    Razzak, Shaikh A; Ali, Saad Aldin M; Hossain, Mohammad M; Mouanda, Alexis Nzila

    2016-11-01

    The present research is focused on cultivation of microalgae strain Chlorella vulgaris for bio-fixation of CO2 coupled with biomass production. In this regard, a single semi-batch vertical tubular photobioreactor and four similar photobioreactors in series have been employed. The concentration of CO2 in the feed stream was varied from 2 to 12 % (v/v) by adjusting CO2 to air ratio. The amount of CO2 capture and algae growth were monitored by measuring decrease of CO2 concentration in the gas phase, microalgal cell density, and algal biomass production rate. The results show that 4 % CO2 gives maximum amount of biomass (0.9 g L(-1)) and productivity (0.118 g L(-1) day(-1)) of C. vulgaris in a single reactor. In series reactors, average productivity per reactor found to be 0.078 g L(-1) day(-1). The maximum CO2 uptake for single reactor also found with 4 % CO2, and it is around 0.2 g L(-1) day(-1). In series reactors, average CO2 uptake is 0.13 g L(-1) day(-1) per reactor. TOC analysis shows that the carbon content of the produced biomass is around 40.67 % of total weight. The thermochemical characteristics of the cultivated C. vulgaris samples were analyzed in the presence of air. All samples burn above 200 °C and the combustion rate become faster at around 600 °C. Almost 98 wt% of the produced biomass is combustible in this range.

  19. Energetic response of Chlorella vulgaris to alpha radiation and PCB stress

    SciTech Connect

    Schaffer, S.A.

    1982-01-01

    This research project has evaluated the bioenergetic response of the green alga Chlorella vulgaris following acute exposure to either the physical stress of radiation or the chemical stress of PCBs. After exposure, changes in survival or growth, adenylate pools (ATP, ADP, and AMP), CO/sub 2/ fixation and oxygen evolution and uptake were measured. By employing anaerobic conditions, or the electron transport inhibitor DCMU or dark conditions separately and in specific combinations, this study evaluated the response of three separate algal ATP producing mechanisms (respiration, total and cyclic photophosphorylation) to alpha radiation or PCB. The use of the adenylate energy charge ratio as an indicator of stress was also evaluated. The results of the radiation experiments indicated that alpha particle exposure between 25 to 275 rads caused a one-hour latent demand for ATP due to radioinduced DNA repair. In order to compensate for this ATP demand, nonessential utilization of ATP was decreased by slowing the rate of carbon fixation. The results also suggest that use of radiation as a tool to study algal physiology. The data obtained from the PCB experiments again showed each phosphorylation mechanism to be insensitive to 10, 100 and 200 ppm Aroclor 1254 exposures. Data suggest, however, that PCBs caused an increased photosynthetic rate, and total adenylate pool with decreased growth. The use of the adenylate energy charge ratio as a stress indicator was assessed. Because this ratio did not fluctuate at doses of radiation or PCBs that caused reduced survival and growth rates, this study concluded that for Chlorella the adenylate energy charge ration was a poor indicator of sublethal stress.

  20. The influence of extracellular compounds produced by selected Baltic cyanobacteria, diatoms and dinoflagellates on growth of green algae Chlorella vulgaris

    NASA Astrophysics Data System (ADS)

    Żak, Adam; Kosakowska, Alicja

    2015-12-01

    Secondary metabolites produced by bacteria, fungi, algae and plants could affect the growth and development of biological and agricultural systems. This natural process that occurs worldwide is known as allelopathy. The main goal of this work was to investigate the influence of metabolites obtained from phytoplankton monocultures on the growth of green algae Chlorella vulgaris. We selected 6 species occurring in the Baltic Sea from 3 different taxonomic groups: cyanobacteria (Aphanizomenon flos-aquae; Planktothrix agardhii), diatoms (Thalassiosira pseudonana; Chaetoceros wighamii) and dinoflagellates (Alexandrium ostenfeldii; Prorocentrum minimum). In this study we have demonstrated that some of selected organisms caused allelopathic effects against microalgae. Both the negative and positive effects of collected cell-free filtrates on C. vulgaris growth, chlorophyll a concentration and fluorescence parameters (OJIP, QY, NPQ) have been observed. No evidence has been found for the impact on morphology and viability of C. vulgaris cells.

  1. Azoxystrobin-induced excessive reactive oxygen species (ROS) production and inhibition of photosynthesis in the unicellular green algae Chlorella vulgaris.

    PubMed

    Liu, Lei; Zhu, Bin; Wang, Gao-Xue

    2015-05-01

    This study investigated the short-term toxicity of azoxystrobin (AZ), one of strobilurins used as an effective fungicidal agent to control the Asian soybean rust, on aquatic unicellular algae Chlorella vulgaris. The median percentile inhibition concentration (IC₅₀) of AZ for C. vulgaris was found to be 510 μg L(-1). We showed that the algal cells were obviously depressed or shrunk in 300 and 600 μg L(-1) AZ treatments by using the electron microscopy. Furthermore, 19, 75, and 300 μg L(-1) AZ treatments decreased the soluble protein content and chlorophyll concentrations in C. vulgaris and altered the energy-photosynthesis-related mRNA expression levels in 48- and 96-h exposure periods. Simultaneously, our results showed that AZ could increase the total antioxidant capacity (T-AOC) level and compromise superoxide dismutase (SOD), peroxidase (POD), glutathione S transferase (GST), glutathione peroxidase (GPx) activities, and glutathione (GSH) content. These situations might render C. vulgaris more vulnerable to oxidative damage. Overall, the present study indicated that AZ might be toxic to the growth of C. vulgaris, affect energy-photosynthesis-related mRNA expressions, and induce reactive oxygen species (ROS) overproduction in C. vulgaris.

  2. Micro-columns packed with Chlorella vulgaris immobilised on silica gel for mercury speciation.

    PubMed

    Tajes-Martínez, P; Beceiro-González, E; Muniategui-Lorenzo, S; Prada-Rodríguez, D

    2006-02-28

    A method has been developed for mercury speciation in water by using columns packed with Chlorella vulgaris immobilised on silica gel. The method involves the retention of CH(3)Hg(+) and Hg(2+) in micro-columns prepared by packing immobilised algae in polypropylene tubes, followed by selective and sequential elution with 0.03 and 1.5M HCl for CH(3)Hg(+) and Hg(2+), respectively. The adsorption capacity of the micro-algae for Hg(2+) and CH(3)Hg(+) has been evaluated using free and immobilised C. vulgaris. The efficiency uptake for both species at pH 3 was higher than 97%. Studies were carried out on the effect of retention and elution conditions for both species. Furthermore, the stability of mercury species retained on algae-silica gel micro-columns and lifetime of the columns were also investigated. Hg(2+) showed a higher stability than CH(3)Hg(+) at 0 degrees C (21 and 3 days, respectively) and a better lifetime than for the organic species. The developed method was applied to the analysis of spiked tap, sea and wastewater samples. Recovery studies on tap and filtered seawater provided results between 96+/-3 and 106+/-2 for Hg(2+) and from 98+/-5 to 107+/-5 for CH(3)Hg(+), for samples spiked with single species. For samples spiked with both CH(3)Hg(+) and Hg(2+), the average recoveries varied from 96+/-5 to 99+/-3 and from 103+/-6 to 115+/-5 for Hg(2+) and CH(3)Hg(+), respectively. However, the percentages of retention and elution on wastewater and unfiltered seawater were only adequate for the inorganic species.

  3. CO2 Biofixation and Growth Kinetics of Chlorella vulgaris and Nannochloropsis gaditana.

    PubMed

    Adamczyk, Michał; Lasek, Janusz; Skawińska, Agnieszka

    2016-08-01

    CO2 biofixation was investigated using tubular bioreactors (15 and 1.5 l) either in the presence of green algae Chlorella vulgaris or Nannochloropsis gaditana. The cultivation was carried out in the following conditions: temperature of 25 °C, inlet-CO2 of 4 and 8 vol%, and artificial light enhancing photosynthesis. Higher biofixation were observed in 8 vol% CO2 concentration for both microalgae cultures than in 4 vol%. Characteristic process parameters such as productivity, CO2 fixation, and kinetic rate coefficient were determined and discussed. Simplified and advanced methods for determination of CO2 fixation were compared. In a simplified method, it is assumed that 1 kg of produced biomass equals 1.88 kg recycled CO2. Advance method is based on empirical results of the present study (formula with carbon content in biomass). It was observed that application of the simplified method can generate large errors, especially if the biomass contains a relatively low amount of carbon. N. gaditana is the recommended species for CO2 removal due to a high biofixation rate-more than 1.7 g/l/day. On day 10 of cultivation, the cell concentration was more than 1.7 × 10(7) cells/ml. In the case of C. vulgaris, the maximal biofixation rate and cell concentration did not exceed 1.4 g/l/day and 1.3 × 10(7) cells/ml, respectively.

  4. Photosystem II Excitation Pressure and Photosynthetic Carbon Metabolism in Chlorella vulgaris.

    PubMed Central

    Savitch, L. V.; Maxwell, D. P.; Huner, NPA.

    1996-01-01

    Chlorella vulgaris grown at 5[deg]C/150 [mu]mol m-2 s-1 mimics cells grown under high irradiance (27[deg]C/2200 [mu]mol m-2 s-1). This has been rationalized through the suggestion that both populations of cells were exposed to comparable photosystem II (PSII) excitation pressures measured as the chlorophyll a fluorescence quenching parameter, 1 - qP (D.P. Maxwell, S. Falk, N.P.A. Huner [1995] Plant Physiol 107: 687-694). To assess the possible role(s) of feed-back mechanisms on PSII excitation pressure, stromal and cytosolic carbon metabolism were examined. Sucrose phosphate synthase and fructose-1,6-bisphosphatase activities as well as the ratios of fructose-1,6-bisphosphate/fructose-6-phosphate and sucrose/starch indicated that cells grown at 27[deg]C/2200 [mu]mol m-2 s-1 appeared to exhibit a restriction in starch metabolism. In contrast, cells grown at 5[deg]C/150 [mu]mol m-2 s-1 appeared to exhibit a restriction in the sucrose metabolism based on decreased cytosolic fructose-1,6- bisphosphatase and sucrose phosphate synthase activities as well as a low sucrose/starch ratio. These metabolic restrictions may feed-back on photosynthetic electron transport and, thus, contribute to the observed PSII excitation pressure. We conclude that, although PSII excitation pressure may reflect redox regulation of photosynthetic acclimation to light and temperature in C. vulgaris, it cannot be considered the primary redox signal. Alternative metabolic sensing/signaling mechanisms are discussed. PMID:12226279

  5. Phytohormones as regulators of heavy metal biosorption and toxicity in green alga Chlorella vulgaris (Chlorophyceae).

    PubMed

    Piotrowska-Niczyporuk, Alicja; Bajguz, Andrzej; Zambrzycka, Elżbieta; Godlewska-Żyłkiewicz, Beata

    2012-03-01

    The present study was undertaken to test the influence of exogenously applied phytohormones: auxins (IAA, IBA, NAA, PAA), cytokinins (BA, CPPU, DPU, 2iP, Kin, TDZ, Z), gibberellin (GA(3)), jasmonic acid (JA) as well as polyamine - spermidine (Spd) upon the growth and metabolism of green microalga Chlorella vulgaris (Chlorophyceae) exposed to heavy metal (Cd, Cu, Pb) stress. The inhibitory effect of heavy metals on algal growth, metabolite accumulation and enzymatic as well as non-enzymatic antioxidant system was arranged in the following order: Cd > Pb > Cu. Exogenously applied phytohormones modify the phytotoxicity of heavy metals. Auxins, cytokinins, gibberellin and spermidine (Spd) can alleviate stress symptoms by inhibiting heavy metal biosorption, restoring algal growth and primary metabolite level. Moreover, these phytohormones and polyamine stimulate antioxidant enzymes' (superoxide dismutase, ascorbate peroxidase, catalase) activities and ascorbate as well as glutathione accumulation by producing increased antioxidant capacity in cells growing under abiotic stress. Increased activity of antioxidant enzymes reduced oxidative stress expressed by lipid peroxidation and hydrogen peroxide level. In contrast JA enhanced heavy metal toxicity leading to increase in metal biosorption and ROS generation. The decrease in cell number, chlorophylls, carotenoids, monosaccharides, soluble proteins, ascorbate and glutathione content as well as antioxidant enzyme activity was also obtained in response to JA and heavy metals. Determining the stress markers (lipid peroxidation, hydrogen peroxide) and antioxidants' level as well as antioxidant enzyme activity in cells is important for understanding the metal-specific mechanisms of toxicity and that these associated novel endpoints may be useful metrics for accurately predicting toxicity. The data suggest that phytohormones and polyamine play an important role in the C. vulgaris responding to abiotic stressor and algal

  6. The role of phosphorus in the metabolism of arsenate by a freshwater green alga, Chlorella vulgaris.

    PubMed

    Baker, Josh; Wallschläger, Dirk

    2016-11-01

    A freshwater microalga, Chlorella vulgaris, was grown in the presence of varying phosphate concentrations (<10-500μg/L P) and environmentally realistic concentrations of arsenate (As(V)) (5-50μg/L As). Arsenic speciation in the culture medium and total cellular arsenic were measured using AEC-ICP-MS and ICP-DRC-MS, respectively, to determine arsenic biotransformation and uptake in the various phosphorus scenarios. At high phosphate concentration in the culture medium, >100μg/L P, the uptake and biotransformation of As(V) was minimal and dimethylarsonate (DMAs(V)) was the dominant metabolite excreted by C. vulgaris, albeit at relatively low concentrations. At common environmental P concentrations, 0-50μg/L P, the uptake and biotransformation of As(V) increased. At these higher As-uptake levels, arsenite (As(III)) was the predominant metabolite excreted from the cell. The concentrations of As(III) in these low P conditions were much higher than the concentrations of methylated arsenicals observed at the various P concentrations studied. The switchover threshold between the (small) methylation and (large) reduction of As(V) occurred around a cellular As concentration of 1fg/cell. The observed nearly quantitative conversion of As(V) to As(III) under low phosphate conditions indicates the importance of As(V) bio-reduction at common freshwater P concentrations. These findings on the influence of phosphorus on arsenic uptake, accumulation and excretion are discussed in relation to previously published research. The impact that the two scenarios of As(V) metabolism, As(III) excretion at high As(V)-uptake and methylarsenical excretion at low As(V)-uptake, have on freshwater arsenic speciation is discussed.

  7. Subcritical Water Technology for Enhanced Extraction of Biochemical Compounds from Chlorella vulgaris

    PubMed Central

    Awaluddin, S. A.; Thiruvenkadam, Selvakumar; Izhar, Shamsul; Hiroyuki, Yoshida; Danquah, Michael K.; Harun, Razif

    2016-01-01

    Subcritical water extraction (SWE) technology has been used for the extraction of active compounds from different biomass materials with low process cost, mild operating conditions, short process times, and environmental sustainability. With the limited application of the technology to microalgal biomass, this work investigates parametrically the potential of subcritical water for high-yield extraction of biochemicals such as carbohydrates and proteins from microalgal biomass. The SWE process was optimized using central composite design (CCD) under varying process conditions of temperature (180–374°C), extraction time (1–20 min), biomass particulate size (38–250 μm), and microalgal biomass loading (5–40 wt.%). Chlorella vulgaris used in this study shows high volatile matter (83.5 wt.%) and carbon content (47.11 wt.%), giving advantage as a feedstock for biofuel production. The results showed maximum total carbohydrate content and protein yields of 14.2 g/100 g and 31.2 g/100 g, respectively, achieved under the process conditions of 277°C, 5% of microalgal biomass loading, and 5 min extraction time. Statistical analysis revealed that, of all the parameters investigated, temperature is the most critical during SWE of microalgal biomass for protein and carbohydrate production. PMID:27366748

  8. Mechanisms of ammonium assimilation by Chlorella vulgaris F1068: Isotope fractionation and proteomic approaches.

    PubMed

    Liu, Na; Li, Feng; Ge, Fei; Tao, Nengguo; Zhou, Qiongzhi; Wong, Minghung

    2015-08-01

    Removal of ammonium (NH4(+)-N) by microalgae has evoked interest in wastewater treatment, however, the detailed mechanisms of ammonium assimilation remain mysterious. This study investigated the effects of NH4(+)-N concentration on the removal and biotransformation efficiency by Chlorella vulgaris F1068, and explored the mechanisms by (15)N isotope fractionation and proteome approaches. The results showed NH4(+)-N was efficiently removed (84.8%) by F1068 at 10mgL(-1) of NH4(+)-N. The isotope enrichment factor (ε=-2.37±0.08‰) of (15)N isotope fractionation revealed 47.6% biotransformation at above condition, while 7.0% biotransformation at 4mgL(-1) of NH4(+)-N (ε=-1.63±0.06‰). This was due to the different expression of glutamine synthetase, a key enzyme in ammonium assimilation, which was up-regulated 6.4-fold at proteome level and 18.0-fold at transcription level. The results will provide a better mechanistic understanding of ammonium assimilation by microalgae and this green technology is expected to reduce the burden of NH4(+)-N removal for municipal sewage treatment plants.

  9. Comparison between several methods of total lipid extraction from Chlorella vulgaris biomass.

    PubMed

    dos Santos, Raquel Rezende; Moreira, Daniel Mendonça; Kunigami, Claudete Norie; Aranda, Donato Alexandre Gomes; Teixeira, Cláudia Maria Luz Lapa

    2015-01-01

    The use of lipids obtained from microalgae biomass has been described as a promising alternative for production of biodiesel to replace petro-diesel. It involves steps such as the cultivation of microalgae, biomass harvesting, extraction and transesterification of lipids. The purpose of the present study was to compare different methods of extracting total lipids. These methods were tested in biomass of Chlorella vulgaris with the solvents ethanol, hexane and a mixture of chloroform:methanol in ratios 1:2 and 2:1. The solvents were associated with other mechanisms of cell disruption such as use of a Potter homogenizer and ultrasound treatment. The percentage of triglycerides in the total lipids was determinated by the glycerol-3-phosphate oxidase-p-chlorophenol method (triglycerides monoreagent K117; Bioclin). Among the tested methods, the mixture of chloroform:methanol (2:1) assisted by ultrasound was most efficient, extracting an average of 19% of total lipids, of which 55% were triglycerides. The gas chromatographic analysis did not show differences in methyl ester profiles of oils extracted under the different methods.

  10. UVA-induced reset of hydroxyl radical ultradian rhythm improves temporal lipid production in Chlorella vulgaris.

    PubMed

    Balan, Ranjini; Suraishkumar, G K

    2014-01-01

    We report for the first time that the endogenous, pseudo-steady-state, specific intracellular levels of the hydroxyl radical (si-OH) oscillate in an ultradian fashion (model system: the microalga, Chlorella vulgaris), and also characterize the various rhythm parameters. The ultradian rhythm in the endogenous levels of the si-OH occurred with an approximately 6 h period in the daily cycle of light and darkness. Further, we expected that the rhythm reset to a shorter period could rapidly switch the cellular redox states that could favor lipid accumulation. We reset the endogenous rhythm through entrainment with UVA radiation, and generated two new ultradian rhythms with periods of approximately 2.97 h and 3.8 h in the light phase and dark phase, respectively. The reset increased the window of maximum lipid accumulation from 6 h to 12 h concomitant with the onset of the ultradian rhythms. Further, the saturated fatty acid content increased approximately to 80% of total lipid content, corresponding to the peak maxima of the hydroxyl radical levels in the reset rhythm.

  11. A kinetic study of pyrolysis and combustion of microalgae Chlorella vulgaris using thermo-gravimetric analysis.

    PubMed

    Agrawal, Ankit; Chakraborty, Saikat

    2013-01-01

    This work uses thermo-gravimetric, differential thermo-gravimetric and differential thermal analyses to evaluate the kinetics of pyrolysis (in inert/N(2) atmosphere) and (oxidative) combustion of microalgae Chlorella vulgaris by heating from 50 to 800 °C at heating rates of 5-40 °C/min. This study shows that combustion produces higher biomass conversion than pyrolysis, and that three stages of decomposition occur in both cases, of which, the second one--consisting of two temperature zones--is the main stage of devolatization. Proteins and carbohydrates are decomposed in the first of the two zones at activation energies of 51 and 45 kJ/mol for pyrolysis and combustion, respectively, while lipids are decomposed in its second zone at higher activation energies of 64 and 63 kJ/mol, respectively. The kinetic expressions of the reaction rates in the two zones for pyrolysis and combustion have been obtained and it has been shown that increased heating rates result in faster and higher conversion.

  12. Impact of excipients in the chronic toxicity of fluoxetine on the alga Chlorella vulgaris.

    PubMed

    Silva, Aurora; Santos, Lúcia H M L M; Delerue-Matos, Cristina; Figueiredo, Sónia A

    2014-01-01

    Fluoxetine is a selective serotonin reuptake inhibitor (SSRI) widely used in the treatment of major depression. It has been detected in surface and wastewaters, being able to negatively affect aquatic organisms. Most of the ecotoxicity studies focused only in pharmaceuticals, though excipients can also pose a risk to non-target organisms. In this work the ecotoxicity of five medicines (three generic formulations and two brand labels) containing the same active substance (fluoxetine hydrochloride) was tested on the alga Chlorella vulgaris, in order to evaluate if excipients can influence their ecotoxicity. Effective concentrations that cause 50% of inhibition (EC50) ranging from 0.25 to 15 mg L⁻¹ were obtained in the growth inhibition test performed for the different medicines. The corresponding values for fluoxetine concentration are 10 times lower. Higher EC50 values had been published for the same alga considering only the toxicity of fluoxetine. Therefore, this increase in toxicity may be attributed to the presence of excipients. Thus more studies on ecotoxicological effects of excipients are required in order to assess the environmental risk they may pose to aquatic organisms.

  13. Cultivation of a microalga Chlorella vulgaris using recycled aqueous phase nutrients from hydrothermal carbonization process.

    PubMed

    Du, Zhenyi; Hu, Bing; Shi, Aimin; Ma, Xiaochen; Cheng, Yanling; Chen, Paul; Liu, Yuhuan; Lin, Xiangyang; Ruan, Roger

    2012-12-01

    This study investigated the feasibility of using recovered nutrients from hydrothermal carbonization (HTC) for cultivation of microalga Chlorella vulgaris. Different dilution multiples of 50, 100 and 200 were applied to the recycled process water from HTC and algal growth was compared among these media and a standard growth medium BG-11. Algae achieved a biomass concentration of 0.79 g/L on 50 × process water after 4 days. Algae removed total nitrogen, total phosphorus and chemical oxygen demand by 45.5-59.9%, 85.8-94.6% and 50.0-60.9%, respectively, on differently diluted process water. The fatty acid methyl ester yields for algae grown on the process water were 11.2% (50 ×), 11.2% (100 ×) and 9.7% (200 ×), which were significantly higher than 4.5% for BG-11. In addition, algae cultivated on process water had 18.9% higher carbon and 7.8% lower nitrogen contents than those on BG-11, indicating that they are very suitable as biofuel feedstocks.

  14. Ecotoxicity tests using the green algae Chlorella vulgaris--a useful tool in hazardous effluents management.

    PubMed

    Silva, Aurora; Figueiredo, Sónia A; Sales, M Goreti; Delerue-Matos, Cristina

    2009-08-15

    The treatment efficiency of laboratory wastewaters was evaluated and ecotoxicity tests with Chlorella vulgaris were performed on them to assess the safety of their environmental discharge. For chemical oxygen demand wastewaters, chromium (VI), mercury (II) and silver were efficiently removed by chemical treatments. A reduction of ecotoxicity was achieved; nevertheless, an EC50 (effective concentration that causes a 50% inhibition in the algae growth) of 1.5% (v/v) indicated still high level of ecotoxicity. For chloride determination wastewaters, an efficient reduction of chromium and silver was achieved after treatment. Regarding the reduction of ecotoxicity observed, EC50 increased from 0.059% to 0.5%, only a 0.02% concentration in the aquatic environment would guarantee no effects. Wastewaters containing phenanthroline/iron (II) complex were treated by chemical oxidation. Treatment was satisfactory concerning chemical parameters, although an increase in ecotoxicity was observed (EC50 reduced from 0.31% to 0.21%). The wastes from the kinetic study of persulphate and iodide reaction were treated with sodium bisulphite until colour was removed. Although they did not reveal significant ecotoxicity, only over 1% of the untreated waste produced observable effects over algae. Therefore, ecotoxicity tests could be considered a useful tool not only in laboratory effluents treatment, as shown, but also in hazardous wastewaters management.

  15. Exploration of upstream and downstream process for microwave assisted sustainable biodiesel production from microalgae Chlorella vulgaris.

    PubMed

    Sharma, Amit Kumar; Sahoo, Pradeepta Kumar; Singhal, Shailey; Joshi, Girdhar

    2016-09-01

    The present study explores the integrated approach for the sustainable production of biodiesel from Chlorella vulgaris microalgae. The microalgae were cultivated in 10m(2) open raceway pond at semi-continuous mode with optimum volumetric and areal production of 28.105kg/L/y and 71.51t/h/y, respectively. Alum was used as flocculent for harvesting the microalgae and optimized at different pH. Lipid was extracted using chloroform: methanol (2:1) and having 12.39% of FFA. Effect of various reaction conditions such as effect of catalyst, methanol:lipid ratio, reaction temperature and time on biodiesel yields were studied under microwave irradiation; and 84.01% of biodiesel yield was obtained under optimized reaction conditions. A comparison was also made between the biodiesel productions under conventional heating and microwave irradiation. The synthesized biodiesel was characterized by (1)H NMR, (13)C NMR, FTIR and GC; however, fuel properties of biodiesel were also studied using specified test methods as per ASTM and EN standards.

  16. Technique for harvesting unicellular algae using colloidal gas aphrons. [Chlorella vulgaris

    SciTech Connect

    Honeycutt, S.S.; Wallis, D.A.; Sebba, F.

    1983-01-01

    A novel technique using colloidal gas aphron (CGA) dispersions has been investigated for harvesting Chlorella vulgaris, a unicellular green algae, from dilute suspension. CGA are very small gas bubbles, on the order of 25 ..mu..m in diameter, that are each encapsulated in an aqueous shell of surfactant solution. The process is based on the technology of CGA flotation, which involves the formation of algae-bubble complexes and their subsequent flotation to the surface. At neutral pH, the efficiency of algae removal was maximized when a cationic surfactant (lauryl pyridinium chloride) was used for CGA generation. At pH 10, both the cationic and anionic (sodium dodecyl benzene sulfonate) CGA dispersions yielded comparable removals. Addition of small quantities of alum (to 10/sup -4/M) improved removals using the cationic CGA, and at pH 10 this combination yielded the maximum removals that were achieved: 52.1% removal after a single application of CGA dispersion (1 to 1, dispersion to sample volume ratio), and 89.2% removal after an additional application. 12 references, 1 figure, 2 tables.

  17. Inhibition of Alkaline Flocculation by Algal Organic Matter for Chlorella vulgaris

    SciTech Connect

    Vandamme, Dries; Beuckels, Annelies; Vadelius, Eric; Depraetere, Orily; Noppe, Wim; Dutta, Abhishek; Foubert, Imogen; Laurens, Lieve; Muylaert, Koenraad

    2016-01-01

    Alkaline flocculation is a promising strategy for the concentration of microalgae for bulk biomass production. However, previous studies have shown that biological changes during the cultivation negatively affect flocculation efficiency. The influence of changes in cell properties and in the quality and composition of algal organic matter (AOM) were studied using Chlorella vulgaris as a model species. In batch cultivation, flocculation was increasingly inhibited over time and mainly influenced by changes in medium composition, rather than biological changes at the cell surface. Total carbohydrate content of the organic matter fraction sized bigger than 3 kDa increased over time and this fraction was shown to be mainly responsible for the inhibition of alkaline flocculation. The monosaccharide identification of this fraction mainly showed the presence of neutral and anionic monosaccharides. An addition of 30–50 mg L-1 alginic acid, as a model for anionic carbohydrate polymers containing uronic acids, resulted in a complete inhibition of flocculation. Furthermore, these results suggest that inhibition of alkaline flocculation was caused by interaction of anionic polysaccharides leading to an increased flocculant demand over time.

  18. Isolation of a novel lutein-protein complex from Chlorella vulgaris and its functional properties.

    PubMed

    Cai, Xixi; Huang, Qimin; Wang, Shaoyun

    2015-06-01

    A novel kind of lutein-protein complex (LPC) was extracted from heterotrophic Chlorella vulgaris through aqueous extraction. The purification procedure contained solubilization of thylakoid proteins by a zwitterionic detergent CHAPS, anion exchange chromatography and gel filtration chromatography. Both wavelength scanning and HPLC analysis confirmed that lutein was the major pigment of the protein-based complex, and the mass ratio of lutein and protein was determined to be 9.72 : 100. Besides showing lipid peroxidation inhibition activity in vitro, LPC exerted significant antioxidant effects against ABTS and DPPH radicals with IC50 of 2.90 and 97. 23 μg mL(-1), respectively. Meanwhile, in vivo antioxidant activity of the complex was evaluated using the mice hepatotoxicity model; LPC significantly suppressed the carbon tetrachloride-induced elevation of serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities, and decreased hepatic malondialdehyde (MDA) levels and the hepatosomatic index. Moreover, LPC could effectively restore the activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) in the treated mice livers. Our findings further the progress in the research of natural protein-based lutein complexes, suggesting that LPC has the potential in hepatoprotection against chemical induced toxicity and in increasing the antioxidant capacity of the defense system in the human body.

  19. The boosted biomass and lipid accumulation in Chlorella vulgaris by supplementation of synthetic phytohormone analogs.

    PubMed

    Liu, Tingting; Liu, Fei; Wang, Chao; Wang, Zhenyao; Li, Yuqin

    2017-02-07

    This study attempted at maximizing biomass and lipid accumulation in Chlorella vulgaris by supplementation of natural abscisic acid (ABA) or synthetic 2,4-dichlorophenoxyacetic acid (2,4-D) and 1-naphthaleneacetic acid (NAA) hormone analogs. Amongst three tested additives, NAA-treatment performed remarkable promoting effect on cell growth and lipid biosynthesis. The favorable lipid productivity (418.6mg/L/d) of NAA-treated cells showed 1.48 and 2.24 times more than that of 2,4-D and ABA. NAA-treatment also positively modified the proportions of saturated (C16:0 and C18:0) and monounsaturated fatty acids (C18:1) which were prone to high-quality biofuels-making. Further, NAA-treatment manipulated endogenous phytohormones metabolism leading to the elevated levels of indole-3-acetic acid, jasmonic acid, and salicylic acid and such hormone accumulation might be indispensable for signal transduction in regulating cell growth and lipid biosynthesis in microalgae. In addition, the economic-feasibility and eco-friendly estimation of NAA additive indicated the higher possibilities in developing affordable and scalable microalgal lipids for biofuels.

  20. Harvesting Chlorella vulgaris by magnetic flocculation using Fe₃O₄ coating with polyaluminium chloride and polyacrylamide.

    PubMed

    Zhao, Yuan; Liang, Wenyan; Liu, Lijun; Li, Feizhen; Fan, Qianlong; Sun, Xiaoli

    2015-12-01

    The harvesting of Chlorella vulgaris was investigated by magnetic flocculation, where the natural magnetite was used as magnetic seeds and the polyaluminium chloride (PACl) and polyacrylamide (PAM) were used as the coating polymer on the Fe3O4 surface. The composite modes of PACl, PAM, and Fe3O4 and their effects on harvesting were studied. The results showed that adding the composite PACl/Fe3O4 first (at (0.625 mmol Al/L)/(10 g/L)) followed by the addition PAM (at 3mg/L) was the optimum dosing strategy. Following this strategy, 99% of cells could be harvested in less than 0.5 min, and it could overcome negative impacts from pH and algal organic matter. Compared to PACl, ζ-potentials of PACl/Fe3O4 were found to be increased substantially from -4.9-8.5 mV to 1.5-19.5 mV at pH range 2.1-12.3. The charge neutralization of PACl/Fe3O4 and sweeping of PAM play an important role in magnetic harvesting of microalgal cells.

  1. Release of reduced inorganic selenium species into waters by the green fresh water algae Chlorella vulgaris.

    PubMed

    Simmons, Denina Bobbie Dawn; Wallschläger, Dirk

    2011-03-15

    The common green fresh water algae Chlorella vulgaris was exposed to starting concentrations of 10 μg/L selenium in the form of selenate, selenite, or selenocyanate (SeCN(-)) for nine days in 10% Bold's basal medium. Uptake of selenate was more pronounced than that of selenite, and there was very little uptake of selenocyanate. Upon uptake of selenate, significant quantities of selenite and selenocyanate were produced by the algae and released back into the growth medium; no selenocyanate was released after selenite uptake. Release of the reduced metabolites after selenate exposure appeared to coincide with increasing esterase activity in solution, indicating that cell death (lysis) was the primary emission pathway. This is the first observation of biotic formation of selenocyanate and its release into waters from a nonindustrial source. The potential environmental implications of this laboratory observation are discussed with respect to the fate of selenium in impacted aquatic systems, the ecotoxicology of selenium bioaccumulation, and the interpretation of environmental selenium speciation data generated, using methods incapable of positively identifying reduced inorganic selenium species, such as selenocyanate.

  2. Photoreduction of chromium(VI) in the presence of algae, Chlorella vulgaris.

    PubMed

    Deng, Lin; Wang, Hongli; Deng, Nansheng

    2006-11-16

    In this thesis, the photochemical reduction of hexavalent chromium Cr(VI) in the presence of algae, Chlorella vulgaris, was investigated under the irradiation of metal halide lamps (lambda = 365 nm, 250 W). The affecting factors of photochemical reduction were studied in detail, such as exposure time, initial Cr(VI) concentration, initial algae concentration and pH. The rate of Cr(VI) photochemical reduction increased with algae concentration increasing, exposure time increasing, initial Cr(VI) concentration decreasing and the decrease of pH. When pH increased to 6, the rate of Cr(VI) photochemical reduction nearly vanished. When initial Cr(VI) concentration ranged from 0.4 to 1.0 mg L(-1) and initial algae concentration ranged from ABS(algae) (the absorbency of algae) = 0.025 to ABS(algae) = 0.180, According to the results of kinetic analyses, the kinetic equation of Cr(VI) photochemical reduction in aqueous solution with algae under 250 W metal halide lamps was V0 = kC(0)(0.1718)A(algae)(0.5235) (C0 was initial concentration of Cr(VI); A(algae) was initial concentration of algae) under the condition of pH 4.

  3. Changes in fatty acid composition of Chlorella vulgaris by hypochlorous acid.

    PubMed

    Park, Ji-Yeon; Choi, Sun-A; Jeong, Min-Ji; Nam, Bora; Oh, You-Kwan; Lee, Jin-Suk

    2014-06-01

    Hypochlorous acid treatment of a microalga, Chlorella vulgaris, was investigated to improve the quality of microalgal lipid and to obtain high biodiesel-conversion yield. Because chlorophyll deactivates the catalyst for biodiesel conversion, its removal in the lipid-extraction step enhances biodiesel productivity. When microalgae contacted the hypochlorous acid, chlorophyll was removed, and resultant changes in fatty acid composition of microalgal lipid were observed. The lipid-extraction yield after activated clay treatment was 32.7 mg lipid/g cell; after NaClO treatment at 0.8% available chlorine concentration, it was 95.2 mg lipid/g cell; and after NaCl electrolysis treatment at the 1 g/L cell concentration, it was 102.4 mg lipid/g cell. While the contents of all of the unsaturated fatty acids except oleic acid, in the microalgal lipid, decreased as the result of NaClO treatment, the contents of all of the unsaturated fatty acids including oleic acid decreased as the result of NaCl electrolysis treatment.

  4. Noncatalytic transformation of the crude lipid of ChlorellaI vulgaris into fatty acid methyl ester (FAME) with charcoal via a thermo-chemical process.

    PubMed

    Kwon, Eilhann E; Jeon, Young Jae; Yi, Haakrho

    2013-02-01

    The noncatalytic transformation of the crude lipid of Chlorella vulgaris (C. vulgaris) into fatty acid methyl ester (FAME) via a thermo-chemical process was mainly investigated in this work. The crude lipid of C. vulgaris was recovered by means of solvent extraction from C. vulgaris cultivated in a raceway pond. The conventional catalyzed transesterification of crude lipid of C. vulgaris is notably inhibited by the impurities contained in the crude lipid of C. vulgaris. These impurities are inevitably derived from the solvent extraction process for C. vulgaris. However, this work presents the noncatalytic transesterification of microalgal lipid into FAME, which could be an alternative option. For example, the noncatalytic transformation of microalgal lipid into FAME provides evidence that the esterification of free fatty acids (FFAs) and the transesterification of triglycerides can be combined into a single step less susceptible to the impurities and with a high conversion efficiency (∼97%).

  5. Potential Alleviation of Chlorella vulgaris and Zingiber officinale on Lead-Induced Testicular Toxicity: an Ultrastructural Study.

    PubMed

    Mustafa, Hesham Noaman

    2015-01-01

    Natural, products were studied to combat reproductive alterations of lead. The current work aimed to disclose the efficacy of Chlorella vulgaris and Zingiber officinale to alleviate lead acetate induced toxicity. Sixty adult male Wistar rats were distributed into four groups. Group 1 was considered control, group 2 received 200 mg/l PbAc water, group 3 received 50 mg/kg/rat of C. vulgaris extract and 200 mg/l PbAc water, and group 4 received 100 mg/kg/rat of Z. officinale and 200 mg/l PbAc water for 90 days. Testis samples were subjected to ultrastructural examination. It was observed that PbAc caused degenerative alterations in the spermatogenic series in many tubules, with a loss of germ cells and vacuoles inside the cytoplasm and between the germ cells. Mitochondria exhibited ballooning, with lost cristae and widening of the interstitial tissue, while nuclear envelopes of primary spermatocytes were broken up, and axonemes of the mid-pieces of the sperms were distorted. With the treatment with C. vulgaris or Z. officinale, there were noticeable improvements in these modifications. It was concluded that both C. vulgaris and Z. officinale represent convincing medicinal components that may be used to ameliorate testicular toxicity in those exposed to lead in daily life with superior potentials revealed by C. vulgaris due to its chelating action.

  6. Cultivation of Chlorella vulgaris and Arthrospira platensis with Recovered Phosphorus from Wastewater by Means of Zeolite Sorption

    PubMed Central

    Markou, Giorgos; Depraetere, Orily; Vandamme, Dries; Muylaert, Koenraad

    2015-01-01

    In this study, zeolite was employed for the separation and recovery of P from synthetic wastewater and its use as phosphorus (P) source for the cultivation of the green microalga Chlorella vulgaris and the cyanobacterium Arthrospira (Spirulina) platensis. At P-loaded zeolite concentration of 0.15–1 g/L, in which P was limited, the two species displayed quite different behavior regarding their growth and biomass composition. C. vulgaris preferred to increase the intracellular P and did not synthesize biomass, while A. platensis synthesized biomass keeping the intracellular P as low as possible. In addition under P limitation, C. vulgaris did display some little alteration of the biomass composition, while A. platensis did it significantly, accumulating carbohydrates around 70% from about 15%–20% (control). Both species could desorb P from zeolite biologically. A. platensis could recover over 65% and C. vulgaris 25% of the P bounded onto zeolite. When P-loaded zeolite concentration increased to 5 g/L, P was adequate to support growth for both species. Especially in the case of C. vulgaris, growth was stimulated from the presence of P-loaded zeolite and produced more biomass compared to the control. PMID:25690037

  7. Cultivation of Chlorella vulgaris and Arthrospira platensis with recovered phosphorus from wastewater by means of zeolite sorption.

    PubMed

    Markou, Giorgos; Depraetere, Orily; Vandamme, Dries; Muylaert, Koenraad

    2015-02-16

    In this study, zeolite was employed for the separation and recovery of P from synthetic wastewater and its use as phosphorus (P) source for the cultivation of the green microalga Chlorella vulgaris and the cyanobacterium Arthrospira (Spirulina) platensis. At P-loaded zeolite concentration of 0.15-1 g/L, in which P was limited, the two species displayed quite different behavior regarding their growth and biomass composition. C. vulgaris preferred to increase the intracellular P and did not synthesize biomass, while A. platensis synthesized biomass keeping the intracellular P as low as possible. In addition under P limitation, C. vulgaris did display some little alteration of the biomass composition, while A. platensis did it significantly, accumulating carbohydrates around 70% from about 15%-20% (control). Both species could desorb P from zeolite biologically. A. platensis could recover over 65% and C. vulgaris 25% of the P bounded onto zeolite. When P-loaded zeolite concentration increased to 5 g/L, P was adequate to support growth for both species. Especially in the case of C. vulgaris, growth was stimulated from the presence of P-loaded zeolite and produced more biomass compared to the control.

  8. Enhanced activity of ADP glucose pyrophosphorylase and formation of starch induced by Azospirillum brasilense in Chlorella vulgaris.

    PubMed

    Choix, Francisco J; Bashan, Yoav; Mendoza, Alberto; de-Bashan, Luz E

    2014-05-10

    ADP-glucose pyrophosphorylase (AGPase) regulates starch biosynthesis in higher plants and microalgae. This study measured the effect of the bacterium Azospirillum brasilense on AGPase activity in the freshwater microalga Chlorella vulgaris and formation of starch. This was done by immobilizing both microorganisms in alginate beads, either replete with or deprived of nitrogen or phosphorus and all under heterotrophic conditions, using d-glucose or Na-acetate as the carbon source. AGPase activity during the first 72h of incubation was higher in C. vulgaris when immobilized with A. brasilense. This happened simultaneously with higher starch accumulation and higher carbon uptake by the microalgae. Either carbon source had similar effects on enzyme activity and starch accumulation. Starvation either by N or P had the same pattern on AGPase activity and starch accumulation. Under replete conditions, the population of C. vulgaris immobilized alone was higher than when immobilized together, but under starvation conditions A. brasilense induced a larger population of C. vulgaris. In summary, adding A. brasilense enhanced AGPase activity, starch formation, and mitigation of stress in C. vulgaris.

  9. Effect of salinity stress on growth, lipid productivity, fatty acid composition, and biodiesel properties in Acutodesmus obliquus and Chlorella vulgaris.

    PubMed

    Pandit, Priti Raj; Fulekar, Madhusudan H; Karuna, Mallampalli Sri Lakshmi

    2017-04-07

    Two microalgae strains including Chlorella vulgaris and Acutodesmus obliquus were grown on BG11 medium with salinity stress ranging from 0.06 to 0.4 M NaCl. Highest lipid content in C. vulgaris and A. obliquus was 49 and 43% in BG11 amended with 0.4 M NaCl. The microalgal strains C. vulgaris and A. obliquus grow better at 0.06 M NaCl concentration than control condition. At 0.06 M NaCl, improved dry biomass content in C. vulgaris and A. obliquus was 0.92 and 0.68 gL(-1), respectively. Stress biomarkers like reactive oxygen species, antioxidant enzyme catalase, and ascorbate peroxidase were also lowest at 0.06 M NaCl concentration revealing that both the microalgal strains are well acclimatized at 0.06 M NaCl concentration. The fatty acid composition of the investigated microalgal strains was also improved by increased NaCl concentration. At 0.4 M NaCl, palmitic acid (37%), oleic acid (15.5%), and linoleic acid (20%) were the dominant fatty acids in C. vulgaris while palmitic acid (54%) and stearic acid (26.6%) were major fatty acids found in A. obliquus. Fatty acid profiling of C. vulgaris and A. obliquus significantly varied with salinity concentration. Therefore, the study showed that salt stress is an effective stress that could increase not only the lipid content but also improved the fatty acid composition which could make C. vulgaris and A. obliquus potential strains for biodiesel production.

  10. Use of orange peel extract for mixotrophic cultivation of Chlorella vulgaris: increased production of biomass and FAMEs.

    PubMed

    Park, Won-Kun; Moon, Myounghoon; Kwak, Min-Su; Jeon, Seungjib; Choi, Gang-Guk; Yang, Ji-Won; Lee, Bongsoo

    2014-11-01

    Mass cultivation of microalgae is necessary to achieve economically feasible production of microalgal biodiesel, but the high cost of nutrients is a major limitation. In this study, orange peel extract (OPE) was used as an inorganic and organic nutrient source for the cultivation of Chlorella vulgaris OW-01. Chemical composition analysis of the OPE indicated that it contains sufficient nutrients for mixotrophic cultivation of C. vulgaris OW-01. Analysis of biomass and FAME production showed that microalgae grown in OPE medium produced 3.4-times more biomass and 4.5-times more fatty acid methyl esters (FAMEs) than cells cultured in glucose-supplemented BG 11 medium (BG-G). These results suggest that growth of microalgae in an OPE-supplemented medium increases lipid production and that OPE has potential for use in the mass cultivation of microalgae.

  11. Combined nitrogen limitation and cadmium stress stimulate total carbohydrates, lipids, protein and amino acid accumulation in Chlorella vulgaris (Trebouxiophyceae).

    PubMed

    Chia, Mathias Ahii; Lombardi, Ana Teresa; da Graça Gama Melão, Maria; Parrish, Christopher C

    2015-03-01

    Metals have interactive effects on the uptake and metabolism of nutrients in microalgae. However, the effect of trace metal toxicity on amino acid composition of Chlorella vulgaris as a function of varying nitrogen concentrations is not known. In this research, C. vulgaris was used to investigate the influence of cadmium (10(-7) and 2.0×10(-8)molL(-1) Cd) under varying nitrogen (2.9×10(-6), 1.1×10(-5) and 1.1×10(-3)molL(-1)N) concentrations on its growth rate, biomass and biochemical composition. Total carbohydrates, total proteins, total lipids, as well as individual amino acid proportions were determined. The combination of Cd stress and N limitation significantly inhibited growth rate and cell density of C. vulgaris. However, increasing N limitation and Cd stress stimulated higher dry weight and chlorophyll a production per cell. Furthermore, biomolecules like total proteins, carbohydrates and lipids increased with increasing N limitation and Cd stress. Ketogenic and glucogenic amino acids were accumulated under the stress conditions investigated in the present study. Amino acids involved in metal chelation like proline, histidine and glutamine were significantly increased after exposure to combined Cd stress and N limitation. We conclude that N limitation and Cd stress affects the physiology of C. vulgaris by not only decreasing its growth but also stimulating biomolecule production.

  12. Characterization of biosynthesized gold nanoparticles from aqueous extract of Chlorella vulgaris and their anti-pathogenic properties

    NASA Astrophysics Data System (ADS)

    Annamalai, Jayshree; Nallamuthu, Thangaraju

    2015-06-01

    In this study, biosynthesis of self-assembled gold nanoparticles (GNPs) was accomplished using an aqueous extract of green microalga, Chlorella vulgaris. The optical, physical, chemical and bactericidal properties of the GNPs were investigated to identify their average shape and size, crystal nature, surface chemistry and toxicity, via UV-visible spectroscopy, scanning electron microscopy, transmission electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy and antimicrobial activity. The sizes of the spherical self-assembled cores of the synthesized GNPs ranged from 2 to 10 nm. The XRD patterns showed a (111) preferential orientation and the crystalline nature of the GNPs. The results of the FTIR analysis suggested that the peptides, proteins, phenol and flavonoid carried out the dual function of effective Au III reduction and successful capping of the GNPs. Human pathogen Candida albicans and Staphylococcus aureus were susceptible to synthesized aqueous GNPs. Thus, biosynthesis, stabilization and self-assembly of the GNPs by Chlorella vulgaris extract can be an example of green chemistry and effective drug in the medicinal field.

  13. Characterization of biosynthesized gold nanoparticles from aqueous extract of Chlorella vulgaris and their anti-pathogenic properties

    NASA Astrophysics Data System (ADS)

    Annamalai, Jayshree; Nallamuthu, Thangaraju

    2014-09-01

    In this study, biosynthesis of self-assembled gold nanoparticles (GNPs) was accomplished using an aqueous extract of green microalga, Chlorella vulgaris. The optical, physical, chemical and bactericidal properties of the GNPs were investigated to identify their average shape and size, crystal nature, surface chemistry and toxicity, via UV-visible spectroscopy, scanning electron microscopy, transmission electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy and antimicrobial activity. The sizes of the spherical self-assembled cores of the synthesized GNPs ranged from 2 to 10 nm. The XRD patterns showed a (111) preferential orientation and the crystalline nature of the GNPs. The results of the FTIR analysis suggested that the peptides, proteins, phenol and flavonoid carried out the dual function of effective Au III reduction and successful capping of the GNPs. Human pathogen Candida albicans and Staphylococcus aureus were susceptible to synthesized aqueous GNPs. Thus, biosynthesis, stabilization and self-assembly of the GNPs by Chlorella vulgaris extract can be an example of green chemistry and effective drug in the medicinal field.

  14. Antioxidant enzyme activity and malondialdehyde levels can be modulated by Piper betle, tocotrienol rich fraction and Chlorella vulgaris in aging C57BL/6 mice

    PubMed Central

    Aliahmat, Nor Syahida; Noor, Mohd Razman Mohd; Yusof, Wan Junizam Wan; Makpol, Suzana; Ngah, Wan Zurinah Wan; Yusof, Yasmin Anum Mohd

    2012-01-01

    OBJECTIVE: The aim of this study was to determine the erythrocyte antioxidant enzyme activity and the superoxide dismutase, catalase, glutathione peroxidase, and plasma malondialdehyde levels in aging mice and to evaluate how these measures are modulated by potential antioxidants, including the tocotrienol-rich fraction, Piper betle, and Chlorella vulgaris. METHOD: One hundred and twenty male C57BL/6 inbred mice were divided into three age groups: young (6 months old), middle-aged (12 months old), and old (18 months old). Each age group consisted of two control groups (distilled water and olive oil) and three treatment groups: Piper betle (50 mg/kg body weight), tocotrienol-rich fraction (30 mg/kg), and Chlorella vulgaris (50 mg/kg). The duration of treatment for all three age groups was two months. Blood was withdrawn from the orbital sinus to determine the antioxidant enzyme activity and the malondialdehyde level. RESULTS: Piper betle increased the activities of catalase, glutathione peroxidase, and superoxide dismutase in the young, middle, and old age groups, respectively, when compared to control. The tocotrienol-rich fraction decreased the superoxide dismutase activity in the middle and the old age groups but had no effect on catalase or glutathione peroxidase activity for all age groups. Chlorella vulgaris had no effect on superoxide dismutase activity for all age groups but increased glutathione peroxidase and decreased catalase activity in the middle and the young age groups, respectively. Chlorella vulgaris reduced lipid peroxidation (malondialdehyde levels) in all age groups, but no significant changes were observed with the tocotrienol-rich fraction and the Piper betle treatments. CONCLUSION: We found equivocal age-related changes in erythrocyte antioxidant enzyme activity when mice were treated with Piper betle, the tocotrienol-rich fraction, and Chlorella vulgaris. However, Piper betle treatment showed increased antioxidant enzymes activity during

  15. Demography of zooplankton (Anuraeopsis fissa, Brachionus rubens and Moina macrocopa) fed Chlorella vulgaris and Scenedesmus acutus cultured on different media.

    PubMed

    Morales-Ventura, Jesús; Nandini, S; Sarma, S S S; Castellanos-Páez, Maria Elena

    2012-09-01

    Generally zooplankton growth is often limited by the quality of their algal diet. A cheaper common practice in aquaculture, is to culture algae with fertilizers; however, the demography of zooplankton when fed these algae has not yet been evaluated. We studied the population growth and life table demography of the rotifers Anuraeopsis fissa and Brachionus rubens, and the cladoceran Moina macrocopa. For this, the algae Scenedesmus acutus or Chlorella vulgaris were cultured on defined (Bold's basal) medium or the commercial liquid fertilizer (Bayfolan). Experiments were conducted at one algal concentration 1.0 x 10(6) cells/mL of C. vulgaris or its equivalent dry weight of 0.5 x 10(6) cells/mL of S. acutus. The population dynamics were tested at 23 +/- 1 degrees C in 100 mL transparent jars, each with 50mL of the test medium, with an initial density of 0.5indiv/mL, for a total of 48 test jars (3 zooplankton 2 algal species x 2 culture media x 4 replicates). For the life table experiments with M. macrocopa, we introduced 10 neonates (<24h old) into each test jar containing the specific algal type and concentration. For the rotifer experiments, we set 5mL tubes with one neonate each and 10 replicates for each algal species and culture medium. We found that the average rotifer life span was not influenced by the diet, but for M. macrocopa fed S. acutus cultured in Bold's medium, the average lifespan was significantly lower than with the other diets. The gross and net reproductive rates of A. fissa (ranging from 18-36 offspring per female) were significantly higher for C vulgaris cultured in Bold medium. Regardless of the culture medium, Chlorella resulted in significantly higher gross and net reproductive rates for B. rubens than S. acutus diets. The reproductive rates of M. macrocopa were significantly higher in all the tested diets except when fed with S. acutus in Bold medium. The population increase rate, derived from growth experiments of A. fissa and B. rubens

  16. Maximization of cell growth and lipid production of freshwater microalga Chlorella vulgaris by enrichment technique for biodiesel production.

    PubMed

    Wong, Y K; Ho, Y H; Ho, K C; Leung, H M; Yung, K K L

    2017-04-01

    Chlorella vulgaris was cultivated under limitation and starvation and under controlled conditions using different concentrations of nitrate (NaNO3) and phosphate (K2HPO4 and KH2PO4) chemicals in modified Bold basal medium (BBM). The biomass and lipid production responses to different media were examined in terms of optical density, cell density, dry biomass, and lipid productivity. In the 12-day batch culture period, the highest biomass productivity obtained was 72.083 mg L(-1) day(-1) under BBM - NcontrolPlimited condition. The highest lipid content, lipid concentration, and lipid productivity obtained were 53.202 %, 287.291 mg/L, and 23.449 mg L(-1) day(-1) under BBM - NControlPDeprivation condition, respectively. Nitrogen had a major effect in the biomass concentration of C. vulgaris, while no significant effect was found for phosphorus. Nitrogen and phosphorus starvation was found to be the strategy affecting the lipid accumulation and affected the lipid composition of C. vulgaris cultures.

  17. First Report of Pseudobodo sp, a New Pathogen for a Potential Energy-Producing Algae: Chlorella vulgaris Cultures

    PubMed Central

    Zhang, Bangzhou; Yang, Luxi; Zhang, Huajun; Zhang, Jingyan; Li, Yi; Zheng, Wei; Tian, Yun; Liu, Jingwen; Zheng, Tianling

    2014-01-01

    Chlorella vulgaris, is a kind of single-celled green algae, which could serve as a potential source of food and energy because of its photosynthetic efficiency. In our study, a pathogenic organism targeting C. vulgaris was discovered. The algae-lytic activity relates to a fraction from lysates of infected C. vulgaris that was blocked upon filtration through a 3 µm filter. 18S rRNA gene sequence analysis revealed that it shared 99.0% homology with the protist Pseudobodo tremulans. Scanning electron microscope analysis showed that Pseudobodo sp. KD51 cells were approximately 4–5 µm long, biflagellate with an anterior collar around the anterior part of the cell in unstressed feeding cells. Besides the initial host, Pseudobodo sp. KD51 could also kill other algae, indicating its relatively wide predatory spectrum. Heat stability, pH and salinity tolerance experiments were conducted to understand their effects on its predatory activities, and the results showed that Pseudobodo sp. KD51 was heat-sensitive, and pH and salinity tolerant. PMID:24599263

  18. Photosensitized destruction of Chlorella vulgaris by Methylene Blue or Nuclear Fast Red combined with hydrogen peroxide under visible light irradiation.

    PubMed

    McCullagh, Cathy; Robertson, Peter K J

    2006-04-01

    A considerable number of investigations have started to elucidate the essential roles biological agents play in the biodeterioration of stone. Chemical biocides are becoming increasingly banned because of the environmental and health hazards associated with these toxic substances. The present study reports the photodynamic effect of Methylene Blue (MB) and Nuclear Fast Red (NFR) in the presence of hydrogen peroxide (H2O2) on the destruction of the algae Chlorella vulgaris (C. vulgaris) under irradiation with visible light. Illumination of C. vulgaris in the presence of MB or NFR combined with H2O2 results in the decomposition of both the algal species and the photosensitizer. The photodynamic effect was investigated under aerobic and anaerobic conditions. Differences in mechanism type are reported and are dependent on both the presence and the absence of oxygen. The behavior of each photosensitizer leads to a Type II mechanism and a Type I/Type II combination for MB and NFR, respectively, being concluded. This novel combination could be effective for the remediation of biofilm-colonized stone surfaces.

  19. Effect of nutrients on the biodegradation of tributyltin (TBT) by alginate immobilized microalga, Chlorella vulgaris, in natural river water.

    PubMed

    Jin, Jing; Yang, Lihua; Chan, Sidney M N; Luan, Tiangang; Li, Yan; Tam, Nora F Y

    2011-01-30

    The removal and degradation of tributyltin (TBT) by alginate immobilized Chlorella vulgaris has been evidenced in our previously published work. The present study was further to investigate the effect of spiked nutrient concentrations on the TBT removal capacity and degradation in the same alginate immobilized C. vulgaris. During the 14-d experiment, compared to the control (natural river water), the spiked nutrient groups (50% or 100% nutrients of the commercial Bristol medium as the reference, marked as 1/2N or 1N) showed more rapid cell proliferation of microalgae and higher TBT removal rate. Moreover, significantly more TBT was adsorbed onto the alginate matrix, but less TBT was taken up by the algal cells of the nutrient groups than that of the control. Mass balance data showed that TBT was lost as inorganic tin in the highest degree in 1N group, followed by 1/2N group and the least was in the control, but the relative abundance of the intermediate products of debutylation (dibutyltin and monobutyltin) were comparable among three groups. In conclusion, the addition of nutrients in contaminated water stimulated the growth and physiological activity of C. vulgaris immobilized in alginate beads and improved its TBT degradation efficiency.

  20. Toxicity of Cu (II) to the green alga Chlorella vulgaris: a perspective of photosynthesis and oxidant stress.

    PubMed

    Chen, Zunwei; Song, Shufang; Wen, Yuezhong; Zou, Yuqin; Liu, Huijun

    2016-09-01

    The toxic effects of Cu (II) on the freshwater green algae Chlorella vulgaris and its chloroplast were investigated by detecting the responses of photosynthesis and oxidant stress. The results showed that Cu (II) arrested the growth of C. vulgaris and presented in a concentration- and time-dependent trend and the SRichards 2 model fitted the inhibition curve best. The chlorophyll fluorescence parameters, including qP, Y (II), ETR, F v /F m , and F v /F 0, were stimulated at low concentration of Cu (II) but declined at high concentration, indicating the photosystem II (PSII) of C. vulgaris was destroyed by Cu (II). The chloroplasts were extracted, and the Hill reaction activity (HRA) of chloroplast was significantly decreased with the increasing Cu (II) concentration under both illuminating and dark condition, and faster decline speed was observed under dark condition. Activities of superoxide dismutase (SOD) and catalase (CAT) and malondialdehyde (MDA) content were also significantly decreased at high concentration Cu (II), companied with a large number of reactive oxygen species (ROS) production. All these results indicated a severe oxidative stress on algal cells occurred as well as the effect on photosynthesis, thus inhibiting the growth of algae, which providing sights to evaluate the phytotoxicity of Cu (II).

  1. Volatile organic compounds released from Microcystis flos-aquae under nitrogen sources and their toxic effects on Chlorella vulgaris.

    PubMed

    Xu, Qinghuan; Yang, Lin; Yang, Wangting; Bai, Yan; Hou, Ping; Zhao, Jingxian; Zhou, Lv; Zuo, Zhaojiang

    2017-01-01

    Eutrophication promotes massive growth of cyanobacteria and algal blooms, which can poison other algae and reduce biodiversity. To investigate the differences in multiple nitrogen (N) sources in eutrophicated water on the emission of volatile organic compounds (VOCs) from cyanobacteria, and their toxic effects on other algal growth, we analyzed VOCs emitted from Microcystis flos-aquae with different types and concentrations of nitrogen, and determined the effects under Normal-N and Non-N conditions on Chlorella vulgaris. M. flos-aquae released 27, 22, 20, 27, 19, 25 and 17 compounds, respectively, with NaNO3, NaNO2, NH4Cl, urea, Ser, Lys and Arg as the sole N source. With the reduction in N amount, the emission of VOCs was increased markedly, and the most VOCs were found under Non-N condition. C. vulgaris cell propagation, photosynthetic pigment and Fv/Fm declined significantly following exposure to M. flos-aquae VOCs under Non-N condition, but not under Normal-N condition. When C. vulgaris cells were treated with two terpenoids, eucalyptol and limonene, the inhibitory effects were enhanced with increasing concentrations. Therefore, multiple N sources in eutrophicated water induce different VOC emissions from cyanobacteria, and reduction in N can cause nutrient competition, which can result in emissions of more VOCs. Those VOCs released from M. flos-aquae cells under Non-N for nutrient competition can inhibit other algal growth. Among those VOCs, eucalyptol and limonene are the major toxic agents.

  2. Selective extraction of intracellular components from the microalga Chlorella vulgaris by combined pulsed electric field-temperature treatment.

    PubMed

    Postma, P R; Pataro, G; Capitoli, M; Barbosa, M J; Wijffels, R H; Eppink, M H M; Olivieri, G; Ferrari, G

    2016-03-01

    The synergistic effect of temperature (25-65 °C) and total specific energy input (0.55-1.11 kWh kgDW(-1)) by pulsed electric field (PEF) on the release of intracellular components from the microalgae Chlorella vulgaris was studied. The combination of PEF with temperatures from 25 to 55 °C resulted in a conductivity increase of 75% as a result of cell membrane permeabilization. In this range of temperatures, 25-39% carbohydrates and 3-5% proteins release occurred and only for carbohydrate release a synergistic effect was observed at 55 °C. Above 55 °C spontaneous cell lysis occurred without PEF. Combined PEF-temperature treatment does not sufficiently disintegrate the algal cells to release both carbohydrates and proteins at yields comparable to the benchmark bead milling (40-45% protein, 48-58% carbohydrates).

  3. Impact of changes in broth composition on Chlorella vulgaris cultivation in a membrane photobioreactor (MPBR) with permeate recycle.

    PubMed

    Discart, V; Bilad, M R; Marbelia, L; Vankelecom, I F J

    2014-01-01

    A membrane photobioreactor (MPBR) is a proven and very useful concept in which microalgae can be simultaneously cultivated and pre-harvested. However, the behavior with respect to accumulation of algogenic organic matter, including transparent exopolymeric particles (TEPs), counter ions and unassimilated nutrients due to the recycling of the medium is still unclear, even though the understanding of this behavior is essential for the optimization of microalgae processing. Therefore, the dynamics of these compounds, especially TEPs, during coupled cultivation and harvesting of Chlorella vulgaris in an MPBR with permeate recycle are addressed in this study. Results show that TEPs are secreted during algae cell growth, and that their presence is thus inevitable. In the system with permeate recycle, substances such as counter ions and unassimilated nutrients get accumulated in the system. This was proven to limit the algae growth, together with the occurrence of bioflocculation due to an increasing broth pH.

  4. Assessment of a tannin-based organic polymer to harvest Chlorella vulgaris biomass from swine wastewater digestate phycoremediation.

    PubMed

    Mezzari, M P; da Silva, M L B; Pirolli, M; Perazzoli, S; Steinmetz, R L R; Nunes, E O; Soares, H M

    2014-01-01

    This study investigated the efficiency of an organic tannin polymer alone or amended with polyacrylamide to harvest Chlorella vulgaris biomass grown in a laboratory-scale photobioreactor treating swine wastewater digestate. The effect of biomass concentration, tannin (TAN) dosages and changes in pH were evaluated in jar test experiments. Among the TAN concentrations tested (11, 22, 44, 89, 178 mg L(-1)), 11 mg L(-1) showed the highest biomass recovery (97%). The highest coagulation/ flocculation efficiencies were obtained at pH 5 to 7. Flocculation efficiency improved from 50 to 97% concomitant with the increasing biomass concentrations from 45 to 165 mg L(-1), respectively. Recovery efficiencies above 95% were achieved with the same TAN dosage (11 mg L(-1)) irrespective of the concentration of organic carbon present (75 to 300 mg TOC L(-1)). Overall, the results suggest that TAN could become an interesting alternative choice of non-toxic organic polymer for harvesting Chlorella sp. from organic-rich wastewater.

  5. Nitrate concentration-shift cultivation to enhance protein content of heterotrophic microalga Chlorella vulgaris: Over-compensation strategy.

    PubMed

    Xie, Tonghui; Xia, Yun; Zeng, Yu; Li, Xingrui; Zhang, Yongkui

    2017-02-27

    Protein production from microalgae requires both high cell density during cultivation and high protein content in cells. Heterotrophic microalgae can achieve high cell density, and yet are confronted with the problem of low protein content. Based on over-compensation strategy, a new concentration-shift method was proposed to cultivate heterotrophic Chlorella vulgaris, aiming to increase protein content. With a prior starvation period, microalgae utilized more nitrate and accumulated more proteins compared to one-stage cultivation. Considering the convenience of operation, nitrate-added culture was adopted for producing heterotrophic microalgae, rather than sterile centrifugal culture. Operating parameters including nitrate concentration in N-deficient medium, N-starved time and nitrate concentration in N-rich medium were optimized, which were 0.18gl(-1), 38h and 2.45gl(-1), respectively. Under the optimized conditions, protein content in heterotrophic Chlorella reached 44.3%. Furthermore, the heterotrophic microalga was suggested to be a potential single-cell protein source according to the amino acid composition.

  6. Chlorella vulgaris Attenuates Dermatophagoides Farinae-Induced Atopic Dermatitis-Like Symptoms in NC/Nga Mice.

    PubMed

    Kang, Heerim; Lee, Chang Hyung; Kim, Jong Rhan; Kwon, Jung Yeon; Seo, Sang Gwon; Han, Jae Gab; Kim, Byung Gon; Kim, Jong-Eun; Lee, Ki Won

    2015-09-02

    Atopic dermatitis (AD) is a chronic and inflammatory skin disease that can place a significant burden on quality of life for patients. AD most frequently appears under the age of six and although its prevalence is increasing worldwide, therapeutic treatment options are limited. Chlorella vulgaris (CV) is a species of the freshwater green algae genus chlorella, and has been reported to modulate allergy-inducible factors when ingested. Here, we examined the effect of CV supplementation on AD-like symptoms in NC/Nga mice. CV was orally administrated for six weeks while AD-like symptoms were induced via topical application of Dermatophagoides farinae extract (DFE). CV treatment reduced dermatitis scores, epidermal thickness, and skin hydration. Histological analysis also revealed that CV treatment reduced DFE-induced eosinophil and mast cell infiltration into the skin, while analysis of serum chemokine levels indicated that CV treatment downregulated thymus- and activation-regulated chemokine (TARC) and macrophage-derived chemokine (MDC) levels. In addition, CV treatment downregulated mRNA expression levels of IL-4 and IFN-γ. Taken together, these results suggest that CV extract may have potential as a nutraceutical ingredient for the prevention of AD.

  7. Chlorella vulgaris Attenuates Dermatophagoides Farinae-Induced Atopic Dermatitis-Like Symptoms in NC/Nga Mice

    PubMed Central

    Kang, Heerim; Lee, Chang Hyung; Kim, Jong Rhan; Kwon, Jung Yeon; Seo, Sang Gwon; Han, Jae Gab; Kim, Byung Gon; Kim, Jong-Eun; Lee, Ki Won

    2015-01-01

    Atopic dermatitis (AD) is a chronic and inflammatory skin disease that can place a significant burden on quality of life for patients. AD most frequently appears under the age of six and although its prevalence is increasing worldwide, therapeutic treatment options are limited. Chlorella vulgaris (CV) is a species of the freshwater green algae genus chlorella, and has been reported to modulate allergy-inducible factors when ingested. Here, we examined the effect of CV supplementation on AD-like symptoms in NC/Nga mice. CV was orally administrated for six weeks while AD-like symptoms were induced via topical application of Dermatophagoides farinae extract (DFE). CV treatment reduced dermatitis scores, epidermal thickness, and skin hydration. Histological analysis also revealed that CV treatment reduced DFE-induced eosinophil and mast cell infiltration into the skin, while analysis of serum chemokine levels indicated that CV treatment downregulated thymus- and activation-regulated chemokine (TARC) and macrophage-derived chemokine (MDC) levels. In addition, CV treatment downregulated mRNA expression levels of IL-4 and IFN-γ. Taken together, these results suggest that CV extract may have potential as a nutraceutical ingredient for the prevention of AD. PMID:26404252

  8. Accumulation fatty acids of in Chlorella vulgaris under heterotrophic conditions in relation to activity of acetyl-CoA carboxylase, temperature, and co-immobilization with Azospirillum brasilense

    NASA Astrophysics Data System (ADS)

    Leyva, Luis A.; Bashan, Yoav; Mendoza, Alberto; de-Bashan, Luz E.

    2014-10-01

    The relation between fatty acid accumulation, activity of acetyl-CoA carboxylase (ACC), and consequently lipid accumulation was studied in the microalgae Chlorella vulgaris co-immobilized with the plant growth-promoting bacterium Azospirillum brasilense under dark heterotrophic conditions with Na acetate as a carbon source. In C. vulgaris immobilized alone, cultivation experiments for 6 days showed that ACC activity is directly related to fatty acid accumulation, especially in the last 3 days. In co-immobilization experiments, A. brasilense exerted a significant positive effect over ACC activity, increased the quantity in all nine main fatty acids, increased total lipid accumulation in C. vulgaris, and mitigated negative effects of nonoptimal temperature for growth. No correlation between ACC activity and lipid accumulation in the cells was established for three different temperatures. This study demonstrated that the interaction between A. brasilense and C. vulgaris has a significant effect on fatty acid and lipid accumulation in the microalgae.

  9. Evolutionary trade-off between defence against grazing and competitive ability in a simple unicellular alga, Chlorella vulgaris.

    PubMed Central

    Yoshida, Takehito; Hairston, Nelson G.; Ellner, Stephen P.

    2004-01-01

    Trade-offs between defence and other fitness components are expected in principle, and can have major qualitative impacts on ecological dynamics. Here we show that such a trade-off exists even in the simple unicellular alga Chlorella vulgaris. We grew algal populations for multiple generations in either the presence ('grazed algae') or absence ('non-grazed algae') of the grazing rotifer Brachionus calyciflorus, and then evaluated their defence and competitive abilities. Grazed algae were better defended, yielding rotifer growth rate 32% below that of animals fed non-grazed algae, but they also had diminished competitive ability, with a growth rate under nutrient-limiting conditions 28% below that of non-grazed algae. Grazed algae also had a smaller cell size and were more concentrated in carbon and nitrogen. Thus, C. vulgaris genotypes vary phenotypically in their position along a trade-off curve between defence against grazing and competitive ability. This genetic variation underlies rapid algal evolution that significantly alters the ecological predator-prey cycles between rotifers and algae. PMID:15347519

  10. A hermetic self-sustained microbial solar cell based on Chlorella vulgaris and a versatile charge transfer chain

    NASA Astrophysics Data System (ADS)

    Pan, Keliang; Zhou, Peijiang

    2015-10-01

    A hermetic noble-metal-free membrane-less microbial solar cell (MSC) is established. The substances decomposition and regeneration in this MSC are carried out only by Chlorella vulgaris simultaneously. The conversion of metabolism types of C. vulgaris is controlled only by illumination. By using a pleiotropic redox mediator and a cupric hexacyanoferrate modified cathode, a two-phase three-stage charge transfer chain is formed. Through this pathway, the one microorganism self-sustained system gets a long-term power output up to 0.04773 mW/cm2 at 0.423 V without any material exchange with external, which is 50 times higher than that obtained from the original system. Benefiting from this electron buffer system, the battery will achieve an electricity generation in both light and dark conditions. There is almost no consumption of any substrates throughout the stabilized process, and no more additions are required. This maintenance-free and extremely inexpensive reactor with a simple structure and a long service life demonstrates the possibility of combining the microbial, chemical and photo cells.

  11. Growth, survival and reproduction in Chlorella vulgaris and C. variegata with respect to culture age and under different chemical factors.

    PubMed

    Agrawal, S C; Manisha

    2007-01-01

    Batch cultures of Chlorella vulgaris and C. variegata reproducing about twice every 5 d within 0-15 d had vegetative cells and autospore mother cells in the ratio of about 19 : 1. Continuous slow or negligible and/or no growth in > 15-d-old control cultures or in young cultures supplied with the antibiotics streptomycin, penicillin, amoxycillin (10-1000 ppm) or tetracycline (10, 100 ppm), and pesticides carbofuran, gammaxine, moticop or iralon (1-100 ppm) was due to slow autospore mother cells dehiscence (leading to an increase in their percentage); while negligible and/or no growth of both algal species in sewage water (100, 25%), detergent (0.1-1%), petrol or kerosene (5-20 %), benzene, toluene or phenol (5, 10%) and pesticides rogor or endosulfan (1, 10 ppm) was due to vegetative cells failure to differentiate into auto-spore mother cells (leading to decreased/zero autospore mother cells percentage) and/or rapid death of all cells. C. variegata was equally or slightly more sensitive to different chemical stress than C. vulgaris.

  12. Intensity of blue LED light: a potential stimulus for biomass and lipid content in fresh water microalgae Chlorella vulgaris.

    PubMed

    Atta, Madiha; Idris, Ani; Bukhari, Ataullah; Wahidin, Suzana

    2013-11-01

    Light quality and the intensity are key factors which render microalgae as a potential source of biodiesel. In this study the effects of various intensities of blue light and its photoperiods on the growth and lipid content of Chlorella vulgaris were investigated by using LED (Light Emitting Diode) in batch culture. C. vulgaris was grown for 13 days at three different light intensities (100, 200 and 300 μmol m(-2)s(-1)). Effect of three different light and dark regimes (12:12, 16:08 and 24:00 h Light:Dark) were investigated for each light intensity at 25°C culture temperature. Maximum lipid content (23.5%) was obtained due to high efficiency and deep penetration of 200 μmol m(-2)s(-1) of blue light (12:12 L:D) with improved specific growth (1.26 d(-1)) within reduced cultivation time of 8 days. White light could produce 20.9% lipid content in 10 days at 16:08 h L:D.

  13. Improving protein production of indigenous microalga Chlorella vulgaris FSP-E by photobioreactor design and cultivation strategies.

    PubMed

    Chen, Chun-Yen; Lee, Po-Jen; Tan, Chung Hong; Lo, Yung-Chung; Huang, Chieh-Chen; Show, Pau Loke; Lin, Chih-Hung; Chang, Jo-Shu

    2015-06-01

    Fish meal is currently the major protein source for commercial aquaculture feed. Due to its unstable supply and increasing price, fish meal is becoming more expensive and its availability is expected to face significant challenges in the near future. Therefore, feasible alternatives to fish meal are urgently required. Microalgae have been recognized as the most promising candidates to replace fish meal because the protein composition of microalgae is similar to fish meal and the supply of microalgae-based proteins is sustainable. In this study, an indigenous microalga (Chlorella vulgaris FSP-E) with high protein content was selected, and its feasibility as an aquaculture protein source was explored. An innovative photobioreactor (PBR) utilizing cold cathode fluorescent lamps as an internal light source was designed to cultivate the FSP-E strain for protein production. This PBR could achieve a maximum biomass and protein productivity of 699 and 365 mg/L/day, respectively, under an optimum urea and iron concentration of 12.4 mM and 90 μM, respectively. In addition, amino acid analysis of the microalgal protein showed that up to 70% of the proteins in this microalgal strain consist of indispensable amino acids. Thus, C. vulgaris FSP-E appears to be a viable alternative protein source for the aquaculture industry.

  14. Evolutionary trade-off between defence against grazing and competitive ability in a simple unicellular alga, Chlorella vulgaris.

    PubMed

    Yoshida, Takehito; Hairston, Nelson G; Ellner, Stephen P

    2004-09-22

    Trade-offs between defence and other fitness components are expected in principle, and can have major qualitative impacts on ecological dynamics. Here we show that such a trade-off exists even in the simple unicellular alga Chlorella vulgaris. We grew algal populations for multiple generations in either the presence ('grazed algae') or absence ('non-grazed algae') of the grazing rotifer Brachionus calyciflorus, and then evaluated their defence and competitive abilities. Grazed algae were better defended, yielding rotifer growth rate 32% below that of animals fed non-grazed algae, but they also had diminished competitive ability, with a growth rate under nutrient-limiting conditions 28% below that of non-grazed algae. Grazed algae also had a smaller cell size and were more concentrated in carbon and nitrogen. Thus, C. vulgaris genotypes vary phenotypically in their position along a trade-off curve between defence against grazing and competitive ability. This genetic variation underlies rapid algal evolution that significantly alters the ecological predator-prey cycles between rotifers and algae.

  15. Effects of cultivation conditions and media composition on cell growth and lipid productivity of indigenous microalga Chlorella vulgaris ESP-31.

    PubMed

    Yeh, Kuei-Ling; Chang, Jo-Shu

    2012-02-01

    The growth and lipid productivity of an isolated microalga Chlorella vulgaris ESP-31 were investigated under different media and cultivation conditions, including phototrophic growth (NaHCO(3) or CO(2), with light), heterotrophic growth (glucose, without light), photoheterotrophic growth (glucose, with light) and mixotrophic growth (glucose and CO(2), with light). C. vulgaris ESP-31 preferred to grow under phototrophic (CO(2)), photoheterotrophic and mixotrophic conditions on nitrogen-rich medium (i.e., Basal medium and Modified Bristol's medium), reaching a biomass concentration of 2-5 g/l. The growth on nitrogen-limiting MBL medium resulted in higher lipid accumulation (20-53%) but slower growth rate. Higher lipid content (40-53%) and higher lipid productivity (67-144 mg/l/d) were obtained under mixotrophic cultivation with all the culture media used. The fatty acid composition of the microalgal lipid comprises over 60-68% of saturated fatty acids (i.e., palmitic acid (C16:0), stearic acid (C18:0)) and monounsaturated acids (i.e., oleic acid (C18:1)). This lipid composition is suitable for biodiesel production.

  16. Nitrous Oxide (N2O) production in axenic Chlorella vulgaris microalgae cultures: evidence, putative pathways, and potential environmental impacts

    NASA Astrophysics Data System (ADS)

    Guieysse, B.; Plouviez, M.; Coilhac, M.; Cazali, L.

    2013-10-01

    Using antibiotic assays and genomic analysis, this study demonstrates nitrous oxide (N2O) is generated from axenic Chlorella vulgaris cultures. In batch assays, this production is magnified under conditions favouring intracellular nitrite accumulation, but repressed when nitrate reductase (NR) activity is inhibited. These observations suggest N2O formation in C. vulgaris might proceed via NR-mediated nitrite reduction into nitric oxide (NO) acting as N2O precursor via a pathway similar to N2O formation in bacterial denitrifiers, although NO reduction to N2O under oxia remains unproven in plant cells. Alternatively, NR may reduce nitrite to nitroxyl (HNO), the latter being known to dimerize to N2O under oxia. Regardless of the precursor considered, an NR-mediated nitrite reduction pathway provides a unifying explanation for correlations reported between N2O emissions from algae-based ecosystems and NR activity, nitrate concentration, nitrite concentration, and photosynthesis repression. Moreover, these results indicate microalgae-mediated N2O formation might significantly contribute to N2O emissions in algae-based ecosystems (e.g. 1.38-10.1 kg N2O-N ha-1 yr-1 in a 0.25 m deep raceway pond operated under Mediterranean climatic conditions). These findings have profound implications for the life cycle analysis of algae biotechnologies and our understanding of the global biogeochemical nitrogen cycle.

  17. Purifying synthetic high-strength wastewater by microalgae chlorella vulgaris under various light emitting diode wavelengths and intensities

    PubMed Central

    2013-01-01

    The high-strength wastewater is now well known as a threat to the natural water since it is highly possible to arouse water eutrophication or algal blooms. The effects of various light emitting diode wavelengths and intensities on the microalgae biological wastewater treatment system was studied in this research. The various nutrient removals and economic efficiencies represented similar variation trends, and these variations under both high C and N loading treatments were similar too. The order for microalgae C. vulgaris reproduction in terms of dry weight and nutrient removal efficiency both were red > white > yellow > blue, under high carbon and nitrogen loading treatments, indicating that the red light was the optimum light wavelength. Furthermore, considering the optimal light intensity in terms of nutrient removal efficiency was 2500 and 2000 μmol/m2•s, while in terms of economic efficiency was 1000, 1500 and 2000 μmol/m2•s. Therefore, the optimum light intensity was found to be 2000 μmol/m2•s. In addition, the optimal experimental illumination time was determined as 120 h. The Chlorella vulgaris microalgae biological wastewater treatment system utilized in this research was able to purify the high-strength carbon and nitrogen wastewater effectively under optimum light wavelength and intensity. PMID:24499586

  18. A comparative study of the biosorption of iron(III)-cyanide complex anions to Rhizopus arrhizus and Chlorella vulgaris

    SciTech Connect

    Aksu, Z.; Calik, A.

    1999-03-01

    In this study a comparative biosorption of iron(III)-cyanide complex anions from aqueous solutions to Rhizopus arrhizus and Chlorella vulgaris was investigated. The iron(III)-cyanide complex ion-binding capacities of the biosorbents were shown as a function of initial pH, initial iron(III)-cyanide complex ion, and biosorbent concentrations. The results indicated that a significant reduction of iron(III)-cyanide complex ions was achieved at pH 13, a highly alkaline condition for both the biosorbents. The maximum loading capacities of the biosorbents were found to be 612.2 mg/g for R.arrhizus at 1,996.2 mg/L initial iron(III)-cyanide complex ion concentration and 387.0 mg/g for C. vulgaris at 845.4 mg/L initial iron(III)-cyanide complex ion concentration at this pH. The Freundlich, Langmuir, and Redlich-Peterson adsorption models were fitted to the equilibrium data at pH 3, 7, and 13. The equilibrium data of the biosorbents could be best fitted by all the adsorption models over the entire concentration range at pH 13.

  19. The reduction of Chlorella vulgaris concentrations through UV-C radiation treatments: A nature-based solution (NBS).

    PubMed

    Chen, Erika S; Bridgeman, Thomas B

    2017-03-25

    Algal blooms have become a pressing issue in inland freshwater systems on local and global scales. A plausible approach to reducing algae without the use of chemical/biological agents is through the use of UV-C radiation from lamps potentially powered by in situ solar panels to eliminate algae. Yet, the quantitative scientific base has not been established. Our objective is to conduct a controlled experiment to quantify the effectiveness of UV-C radiation on the reduction of Chlorella vulgaris, a common algal species in the Great Lakes region. A full factorial design of three intensities of UV-C radiation (0, 15, and 30W) and three sources of C. vulgaris was constructed to test the corresponding hypotheses. Empirical models were constructed to predict the reductions. UV-C radiation effectively reduced the algal concentration with clear differences by radiation level and source of algal water. Algal concentration decreased exponentially over time, with distinct decreasing trends among the radiation intensities and the samples. With 15W UV-C radiation, algal concentration of three samples were reduced to 75.3%, 51.5%, and 70.0% of the initial level within an hour, respectively. We also found a clear density-dependent reduction rate by UV radiation. Using this information, more efficient treatment systems could be constructed and implemented for cleaning algae-contaminated water.

  20. A novel culture medium designed for the simultaneous enhancement of biomass and lipid production by Chlorella vulgaris UTEX 26.

    PubMed

    Ramírez-López, Citlally; Chairez, Isaac; Fernández-Linares, Luis

    2016-07-01

    A novel culture medium to enhance the biomass and lipid production simultaneously by Chlorella vulgaris UTEX 26 was designed in three stages of optimization. Initially, a culture medium was inferred applying the response surface method to adjust six factors [NaNO3, NH4HCO3, MgSO4·7H2O, KH2PO4, K2HPO4 and (NH4)2HPO4], which were selected on the basement of BBM (Bold's Basal Medium) and HAMGM (Highly Assimilable Minimal Growth Medium) culture media. Afterwards, the nitrogen source compound was optimized to reduce both, ammonium and nitrate concentrations. As result of the optimization process, the proposed culture medium improved 40% the biomass (0.73gL(-1)) compared with the BBM medium and 85% the lipid concentration (281mgL(-1)), with respect to HAMGM medium. Some culture media components concentrations were reduced up to 50%. Gas chromatography analysis revealed that C16:0, C18:0, C18:1, C18:2 and C18:3 were the major fatty acids produced by C. vulgaris UTEX 26.

  1. The effect of oil sands process-affected water and model naphthenic acids on photosynthesis and growth in Emiliania huxleyi and Chlorella vulgaris.

    PubMed

    Beddow, Jessica; Johnson, Richard J; Lawson, Tracy; Breckels, Mark N; Webster, Richard J; Smith, Ben E; Rowland, Steven J; Whitby, Corinne

    2016-02-01

    Naphthenic acids (NAs) are among the most toxic organic pollutants present in oil sands process waters (OSPW) and enter marine and freshwater environments through natural and anthropogenic sources. We investigated the effects of the acid extractable organic (AEO) fraction of OSPW and individual surrogate NAs, on maximum photosynthetic efficiency of photosystem II (PSII) (FV/FM) and cell growth in Emiliania huxleyi and Chlorella vulgaris as representative marine and freshwater phytoplankton. Whilst FV/FM in E. huxleyi and C. vulgaris was not inhibited by AEO, exposure to two surrogate NAs: (4'-n-butylphenyl)-4-butanoic acid (n-BPBA) and (4'-tert-butylphenyl)-4-butanoic acid (tert-BPBA), caused complete inhibition of FV/FM in E. huxleyi (≥10 mg L(-1)n-BPBA; ≥50 mg L(-1)tert-BPBA) but not in C. vulgaris. Growth rates and cell abundances in E. huxleyi were also reduced when exposed to ≥10 mg L(-1)n- and tert-BPBA; however, higher concentrations of n- and tert-BPBA (100 mg L(-1)) were required to reduce cell growth in C. vulgaris. AEO at ≥10 mg L(-1) stimulated E. huxleyi growth rate (p ≤ 0.002), yet had no apparent effect on C. vulgaris. In conclusion, E. huxleyi was generally more sensitive to NAs than C. vulgaris. This report provides a better understanding of the physiological responses of phytoplankton to NAs which will enable improved monitoring of NA pollution in aquatic ecosystems in the future.

  2. The interactive effects of microcystin-LR and cylindrospermopsin on the growth rate of the freshwater algae Chlorella vulgaris.

    PubMed

    Pinheiro, Carlos; Azevedo, Joana; Campos, Alexandre; Vasconcelos, Vítor; Loureiro, Susana

    2016-05-01

    Microcystin-LR (MC-LR) and cylindrospermopsin (CYN) are the most representative cyanobacterial cyanotoxins. They have been simultaneously detected in aquatic systems, but their combined ecotoxicological effects to aquatic organisms, especially microalgae, is unknown. In this study, we examined the effects of these cyanotoxins individually and as a binary mixture on the growth rate of the freshwater algae Chlorella vulgaris. Using the MIXTOX tool, the reference model concentration addition (CA) was selected to evaluate the combined effects of MC-LR and CYN on the growth of the freshwater green algae due to its conservative prediction of mixture effect for putative similar or dissimilar acting chemicals. Deviations from the CA model such as synergism/antagonism, dose-ratio and dose-level dependency were also assessed. In single exposures, our results demonstrated that MC-LR and CYN had different impacts on the growth rates of C. vulgaris at the highest tested concentrations, being CYN the most toxic. In the mixture exposure trial, MC-LR and CYN showed a synergistic deviation from the conceptual model CA as the best descriptive model. MC-LR individually was not toxic even at high concentrations (37 mg L(-1)); however, the presence of MC-LR at much lower concentrations (0.4-16.7 mg L(-1)) increased the CYN toxicity. From these results, the combined exposure of MC-LR and CYN should be considered for risk assessment of mixtures as the toxicity may be underestimated when looking only at the single cyanotoxins and not their combination. This study also represents an important step to understand the interactions among MC-LR and CYN detected previously in aquatic systems.

  3. Toxicity of fluorotelomer carboxylic acids to the algae Pseudokirchneriella subcapitata and Chlorella vulgaris, and the amphipod Hyalella azteca.

    PubMed

    Mitchell, Rebecca J; Myers, Anne L; Mabury, Scott A; Solomon, Keith R; Sibley, Paul K

    2011-11-01

    Perfluorinated acids (PFAs) have elicited significant global regulatory and scientific concern due to their persistence and global pervasiveness. A source of PFAs in the environment is through degradation of fluorotelomer carboxylic acids (FTCAs) but little is known about the toxicity of these degradation products. Previous work found that FTCAs were two to three orders of magnitude more toxic to some freshwater invertebrates than their PFA counterparts and exhibited comparable chain-length-toxicity relationships. In this study, we investigated the toxicity of the 6:2, 8:2, and 10:2 saturated (FTsCA) and unsaturated (FTuCA) fluorotelomer carboxylic acids to two species of freshwater algae, Chlorella vulgaris and Pseudokirchneriella subcapitata, and the amphipod, Hyalella azteca. C. vulgaris was generally the most sensitive species, with EC₅₀s of 26.2, 31.8, 11.1, and 4.2 mg/L for the 6:2 FTsCA, 6:2 FTuCA, 8:2 FTuCA, and 10:2 FTsCA, respectively. H. azteca was most sensitive to the 8:2 FTsCA and 10:2 FTuCA, with LC₅₀s of 5.1 and 3.7 mg/L. The toxicity of the FTCAs generally increased with increasing carbon chain length, and with saturation for most of the species tested, with the exception of P. subcapitata, which did not exhibit any trend. These observations agree with chain-length-toxicity relationships previously reported for the PFCAs and support the greater toxicity of the FTCAs compared to PFCAs. However, the toxicity values are approximately 1000-fold above those detected in the environment indicating negligible risk to aquatic invertebrates.

  4. Enhancing bio-butanol production from biomass of Chlorella vulgaris JSC-6 with sequential alkali pretreatment and acid hydrolysis.

    PubMed

    Wang, Yue; Guo, Wanqian; Cheng, Chieh-Lun; Ho, Shih-Hsin; Chang, Jo-Shu; Ren, Nanqi

    2016-01-01

    This study presents a successful butanol production method using alkali and acid pretreated biomass of Chlorella vulgaris JSC-6. The butanol concentration, yield, and productivity were 13.1g/L, 0.58mol/mol sugar, 0.66g/L/h, respectively. Nearly 2.93L/L of biohydrogen was produced during the acidogenesis phase in ABE fermentation. The hydrogen yield and productivity were 0.39mol/mol sugar and 104.2g/L/h respectively. In addition, the high glucose consumption efficiency (97.5%) suggests that the hydrolysate pretreated with NaOH (1%) followed by H2SO4 (3%) did not contain inhibitors to the fermentation. It was also discovered that an excess amount of nitrogen sources arising from hydrolysis of highly concentrated microalgal biomass negatively affected the butanol production. This work demonstrates the technical feasibility of producing butanol from sustainable third-generation feedstock (i.e., microalgal biomass).

  5. Role of extracellular polymeric substances from Chlorella vulgaris in the removal of ammonium and orthophosphate under the stress of cadmium.

    PubMed

    Chen, Biao; Li, Feng; Liu, Na; Ge, Fei; Xiao, Huaixian; Yang, Yixuan

    2015-08-01

    The interactions between the soluble extracellular polymeric substances (S-EPS), bound EPS (B-EPS) of algae and heavy metal, would affect the removal of ammonium (NH4(+)-N) and orthophosphate (PO4(3-)-P) from wastewater by algae-based techniques. This study investigated the role of Cd(2+)-mediated EPS from Chlorella vulgaris on NH4(+)-N and PO4(3-)-P removal. The results showed that the removal efficiencies of NH4(+)-N and PO4(3-)-P still separately remained 62.6% and 64.9% under 1.0mg/L Cd(2+), compared to those without Cd(2+), mainly attributing to enhanced S-EPS and B-EPS contents of the algae. The increased of PS (polysaccharides) and PN (proteins, e.g., tryptophan-like and tyrosine-like components) led to accelerated interactions of Cd(2+) with PS and PN in EPS fractions, especially for B-EPS, due to a higher detected distribution of Cd(2+) (e.g., about 55.4% in B-EPS). Thus, algae-based techniques are stable treatment methods for wastewater in which NH4(+)-N and PO4(3-)-P coexist with heavy metals.

  6. The effects of pH on the growth of Chlorella vulgaris and its interactions with cadmium toxicity.

    PubMed

    Rachlin, J W; Grosso, A

    1991-05-01

    The effects of pH alone, and in combination with exposure to 0.89 microM cadmium, on the growth response of the green alga Chlorella vulgaris were evaluated. Acidic (3.0-6.2) and alkaline (8.3-9.0) pH values retarded the growth of this alga. Optimal growth occurred when the pH of the medium was adjusted to values of 7.5 and 8.0. When the cells were exposed to pH adjusted medium plus the presence of 0.89 microM Cd, a value known to reduce population growth by 50% at the control pH of 6.9, the affects were additive at the acidic (3.0-5.0) pH ranges. At alkaline pH values of 8.3-9.0 all toxicity responses could be explained by pH adjustment alone, indicating that additional cadmium toxicity was absent. At pH values of 7.5 and 8.0, cadmium toxicity was mitigated against, and resultant growth at pH 8.0 was at the same enhanced rate as this pH without cadmium.

  7. Enzymatic transesterification of microalgal oil from Chlorella vulgaris ESP-31 for biodiesel synthesis using immobilized Burkholderia lipase.

    PubMed

    Tran, Dang-Thuan; Yeh, Kuei-Ling; Chen, Ching-Lung; Chang, Jo-Shu

    2012-03-01

    An indigenous microalga Chlorella vulgaris ESP-31 grown in an outdoor tubular photobioreactor with CO(2) aeration obtained a high oil content of up to 63.2%. The microalgal oil was then converted to biodiesel by enzymatic transesterification using an immobilized lipase originating from Burkholderia sp. C20. The conversion of the microalgae oil to biodiesel was conducted by transesterification of the extracted microalgal oil (M-I) and by transesterification directly using disrupted microalgal biomass (M-II). The results show that M-II achieved higher biodiesel conversion (97.3 wt% oil) than M-I (72.1 wt% oil). The immobilized lipase worked well when using wet microalgal biomass (up to 71% water content) as the oil substrate. The immobilized lipase also tolerated a high methanol to oil molar ratio (>67.93) when using the M-II approach, and can be repeatedly used for six cycles (or 288 h) without significant loss of its original activity.

  8. Investigation and modeling of the effects of light spectrum and incident angle on the growth of Chlorella vulgaris in photobioreactors.

    PubMed

    Souliès, Antoine; Legrand, Jack; Marec, Hélène; Pruvost, Jérémy; Castelain, Cathy; Burghelea, Teodor; Cornet, Jean-François

    2016-03-01

    An in-depth investigation of how various illumination conditions influence microalgal growth in photobioreactors (PBR) has been presented. Effects of both the light emission spectrum (white and red) and the light incident angle (0° and 60°) on the PBR surface were investigated. The experiments were conducted in two fully controlled lab-scale PBRs, a torus PBR and a thin flat-panel PBR for high cell density culture. The results obtained in the torus PBR were used to build the kinetic growth model of Chlorella vulgaris taken as a model species. The PBR model was then applied to the thin flat-panel PBR, which was run with various illumination conditions. Its detailed representation of local rate of photon absorption under various conditions (spectral calculation of light attenuation, incident angle influence) enabled the model to take into account all the tested conditions with no further adjustment. This allowed a detailed investigation of the coupling between radiation field and photosynthetic growth. Effects of all the radiation conditions together with pigment acclimation, which was found to be relevant, were investigated in depth. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:247-261, 2016.

  9. Biosynthesis of high yield fatty acids from Chlorella vulgaris NIES-227 under nitrogen starvation stress during heterotrophic cultivation.

    PubMed

    Shen, Xiao-Fei; Chu, Fei-Fei; Lam, Paul K S; Zeng, Raymond J

    2015-09-15

    In this study the heterotrophic cultivation of Chlorella vulgaris NIES-227 fed with glucose was investigated systematically using six media types; combinations of nitrogen repletion/depletion and phosphorus repletion/limitation/depletion. It was found that a high yield of fatty acids (0.88 of fed glucose-COD) and a high content of fatty acid methyl esters (FAMEs) (89% of dry weight) were obtained under nitrogen starved conditions. To our knowledge it is the first report on such high COD conversion yield and FAME content in microalgae. The dominant fatty acid (>50%) was methyl oleate (C18:1), a desirable component for biodiesel synthesis. FAME content under nitrogen starved conditions was significantly higher than under nitrogen sufficient conditions, while phosphorus had no significant influence, indicating that nitrogen starvation was the real "fatty acids trigger" in heterotrophic cultivation. These findings could simplify the downstream extraction process, such as the extrusion of oil from soybeans, and could reduce operating costs by improving the fatty acid yield from waste COD.

  10. Disruption of Chlorella vulgaris cells for the release of biodiesel-producing lipids: a comparison of grinding, ultrasonication, bead milling, enzymatic lysis, and microwaves.

    PubMed

    Zheng, Hongli; Yin, Jilong; Gao, Zhen; Huang, He; Ji, Xiaojun; Dou, Chang

    2011-08-01

    A comparative evaluation of different cell disruption methods for the release of lipids from marine Chlorella vulgaris cells was investigated. The cell growth of C. vulgaris was observed. Lipid concentrations from different disruption methods were determined, and the fatty acid composition of the extracted lipids was analyzed. The results showed that average productivity of C. vulgaris biomass was 208 mg L⁻¹ day⁻¹. The lipid concentrations of C. vulgaris were 5%, 6%, 29%, 15%, 10%, 7%, 22%, 24%, and 18% when using grinding with quartz sand under wet condition, grinding with quartz sand under dehydrated condition, grinding in liquid nitrogen, ultrasonication, bead milling, enzymatic lysis by snailase, enzymatic lysis by lysozyme, enzymatic lysis by cellulose, and microwaves, respectively. The shortest disruption time was 2 min by grinding in liquid nitrogen. The unsaturated and saturated fatty acid contents of C. vulgaris were 71.76% and 28.24%, respectively. The extracted lipids displayed a suitable fatty acid profile for biodiesel [C16:0 (~23%), C16:1 (~23%), and C18:1 (~45%)]. Overall, grinding in liquid nitrogen was identified as the most effective method in terms of disruption efficiency and time.

  11. Kinetic characteristics and modeling of microalgae Chlorella vulgaris growth and CO2 biofixation considering the coupled effects of light intensity and dissolved inorganic carbon.

    PubMed

    Chang, Hai-Xing; Huang, Yun; Fu, Qian; Liao, Qiang; Zhu, Xun

    2016-04-01

    Understanding and optimizing the microalgae growth process is an essential prerequisite for effective CO2 capture using microalgae in photobioreactors. In this study, the kinetic characteristics of microalgae Chlorella vulgaris growth in response to light intensity and dissolved inorganic carbon (DIC) concentration were investigated. The greatest values of maximum biomass concentration (Xmax) and maximum specific growth rate (μmax) were obtained as 2.303 g L(-1) and 0.078 h(-1), respectively, at a light intensity of 120 μmol m(-2) s(-1) and DIC concentration of 17 mM. Based on the results, mathematical models describing the coupled effects of light intensity and DIC concentration on microalgae growth and CO2 biofixation are proposed. The models are able to predict the temporal evolution of C. vulgaris growth and CO2 biofixation rates from lag to stationary phases. Verification experiments confirmed that the model predictions agreed well with the experimental results.

  12. Comprehensive modeling and investigation of the effect of iron on the growth rate and lipid accumulation of Chlorella vulgaris cultured in batch photobioreactors.

    PubMed

    Concas, Alessandro; Steriti, Alberto; Pisu, Massimo; Cao, Giacomo

    2014-02-01

    Recent works have shown that specific strains of microalgae are capable to simultaneously increase their growth rate and lipid content when cultured under suitable concentrations of iron. While these results are promising in view of the exploitation of microalgae for producing biofuels, to the best of our knowledge, no mathematical model capable to describe the effect of iron on lipid accumulation in microalgae, has been so far proposed. A comprehensive mathematical model describing the effect of iron on chlorophyll synthesis, nitrogen assimilation, growth rate and lipid accumulation in a freshwater strain of Chlorella vulgaris is then proposed in this work. Model results are successfully compared with experimental data which confirm the positive effect of growing iron concentrations on lipid productivity of C. vulgaris. Thus, the proposed model might represent a useful tool to optimize iron-based strategies to improve the lipid productivity of microalgal cultures.

  13. Kinetic model of Chlorella vulgaris growth with and without extremely low frequency-electromagnetic fields (EM-ELF).

    PubMed

    Beruto, Dario T; Lagazzo, Alberto; Frumento, Davide; Converti, Attilio

    2014-01-01

    Chlorella vulgaris was grown in two bench-scale photobioreactors with and without the application of a low intensity, low frequency electromagnetic field (EM-ELF) of about 3mT. Cell concentration and tendency of cells to form aggregates inside the reactor were recorded over a 30 days-time period at 0.5L-constant medium volume in the temperature range 289-304K. At 304K, after a cultivation period of 15 days, the rate of cell death became predominant over that of growth. In the temperature range 289-299K, a two step-kinetic model based on the mitotic division and the clusterization processes was developed and critically discussed. The best-fitted curves turned out to have a sigmoid shape, and the competition between mitosis and clusterization was investigated. Without EM-ELF, the temperature dependence of the specific rate constant of the mitotic step yielded an apparent total enthalpy of 15±6kJmol(-1), whose value was not influenced by the EM-ELF application. The electromagnetic field was shown to exert a significant effect on the exothermic clusterization step. The heat exchange due to binding between cells and liquid medium turned out to be -44±5kJmol(-1) in the absence of EM-ELF and -68±8kJmol(-1) when it was active. Optical microscopy observations were in agreement with the model predictions and confirmed that EM-ELF was able to enhance cell clusterization.

  14. Effect of Reaction Temperature on Biodiesel Production from Chlorella vulgaris using CuO/Zeolite as Heterogeneous Catalyst

    NASA Astrophysics Data System (ADS)

    Dianursanti; Delaamira, M.; Bismo, S.; Muharam, Y.

    2017-02-01

    Human needs for fossil energy increase every year. Biodiesel is the main way to resolve this world problem. Biodiesel produces from vegetable oil. But then, the alternative way came from the uses of microalgae in Chlorella vulgaris type causes by its simplicity of growing. In the other hand, this microalgae known for its high lipid content by considering several parameter such as light intensity, medium nutrition, pH and also salinity. Lipid content will be extracted by using Bligh-Dryer method which will be reacted with methanol along transesterification. Beside, there come another matter which is the utilization of homogeny catalyst. The difficulty of separation is the main matter so then biodiesel need to be washed in case normalizing the pH and this process will decrease the quality of biodiesel. To resolve this problem, we’ll be using a heterogeneous catalyst, zeolite, with ability to catalyst the process. Zeolite is easier to separate from the biodiesel so there will not be needed washing process. Heterogeneous catalyst work as well as homogeneous. Variation implemented on transesterification included reaction temperature of 40°C, 60°C, and 80°C. Reaction time, catalyst percentage and the solvent amount remain steady on 4 hours, 3% and 1:400. Complete best result obtained at 60°C with the yield of 36,78%. Through this, heterogeneous catalyst CuO/Zeolite proved to have a capability for replacing homogeneous catalyst and simplify the production of biodiesel particularly in separation step.

  15. Toxicity of cobalt ferrite (CoFe2O4) nanobeads in Chlorella vulgaris: interaction, adaptation and oxidative stress.

    PubMed

    Ahmad, Farooq; Yao, Hongzhou; Zhou, Ying; Liu, Xiaoyi

    2015-11-01

    The potential toxicity of CoFe2O4 nanobeads (NBs) in Chlorella vulgaris was observed up to 72h. Algal cell morphology, membrane integrity and viability were severely compromised due to adsorption and aggregation of NBs on algal surfaces, release of Fe(3+) and Co(2+) ions and possible mechanical damage by NBs. Interactions with NBs and effective decrease in ions released by aggregation and exudation of algal cells as a self defense mechanism were observed by Fourier transform infrared attenuated total reflectance (FTIR-ATR) and inductively coupled plasma mass spectrometry (ICP-MS). The results corroborated CoFe2O4 NBs induced ROS triggered oxidative stress, leading to a reduction in catalase activity, activation of the mutagenic glutathione s-transferase (mu-GST) and acid phosphatase (AP) antioxidant enzymes, and an increase in genetic aberrations, metabolic and cellular signal transduction dysfunction. Circular dichroism (CD) spectra indicated the weak interactions of NBs with BSA, with slight changes in the α-helix structure of BSA confirming conformational changes in structure, hence the potential for functional interactions with biomolecules. Possible interferences of CoFe2O4 NBs with assay techniques and components indicated CoFe2O4 NBs at lower concentration do not show any significant interference with ROS, catalase, mu-GST and no interference with CD measurements. This study showed ROS production is one of the pathways of toxicity initiated by CoFe2O4 NBs and illustrates the complex processes that may occur between organisms and NBs in natural complex ecosystem.

  16. Combined biocidal action of silver nanoparticles and ions against Chlorococcales (Scenedesmus quadricauda, Chlorella vulgaris) and filamentous algae (Klebsormidium sp.).

    PubMed

    Zouzelka, Radek; Cihakova, Pavlina; Rihova Ambrozova, Jana; Rathousky, Jiri

    2016-05-01

    Despite the extensive research, the mechanism of the antimicrobial and biocidal performance of silver nanoparticles has not been unequivocally elucidated yet. Our study was aimed at the investigation of the ability of silver nanoparticles to suppress the growth of three types of algae colonizing the wetted surfaces or submerged objects and the mechanism of their action. Silver nanoparticles exhibited a substantial toxicity towards Chlorococcales Scenedesmus quadricauda, Chlorella vulgaris, and filamentous algae Klebsormidium sp., which correlated with their particle size. The particles had very good stability against agglomeration even in the presence of multivalent cations. The concentration of silver ions in equilibrium with nanoparticles markedly depended on the particle size, achieving about 6 % and as low as about 0.1 % or even less for the particles 5 nm in size and for larger ones (40-70 nm), respectively. Even very limited proportion of small particles together with larger ones could substantially increase concentration of Ag ions in solution. The highest toxicity was found for the 5-nm-sized particles, being the smallest ones in this study. Their toxicity was even higher than that of silver ions at the same silver concentration. When compared as a function of the Ag(+) concentration in equilibrium with 5-nm particles, the toxicity of ions was at least 17 times higher than that obtained by dissolving silver nitrite (if not taking into account the effect of nanoparticles themselves). The mechanism of the toxicity of silver nanoparticles was found complex with an important role played by the adsorption of silver nanoparticles and the ions released from the particles on the cell surface. This mechanism could be described as some sort of synergy between nanoparticles and ions. While our study clearly showed the presence of this synergy, its detailed explanation is experimentally highly demanding, requiring a close cooperation between materials scientists

  17. Statistical evaluation and modeling of cheap substrate-based cultivation medium of Chlorella vulgaris to enhance microalgae lipid as new potential feedstock for biolubricant.

    PubMed

    Mohammad Mirzaie, M A; Kalbasi, M; Mousavi, S M; Ghobadian, B

    2016-05-18

    Chlorella vulgaris (C. vulgaris) microalga was investigated as a new potential feedstock for the production of biodegradable lubricant. In order to enhance microalgae lipid for biolubricant production, mixotrophic growth of C. vulgaris was optimized using statistical analysis of Plackett-Burman (P-B) and response surface methodology (RSM). A cheap substrate-based medium of molasses and corn steep liquor (CSL) was used instead of expensive mineral salts to reduce the total cost of microalgae production. The effects of molasses and CSL concentration (cheap substrates) and light intensity on the growth of microalgae and their lipid content were analyzed and modeled. Designed models by RSM showed good compatibility with a 95% confidence level when compared to the cultivation system. According to the models, optimal cultivation conditions were obtained with biomass productivity of 0.123 g L(-1) day(-1) and lipid dry weight of 0.64 g L(-1) as 35% of dry weight of C. vulgaris. The extracted microalgae lipid presented useful fatty acid for biolubricant production with viscosities of 42.00 cSt at 40°C and 8.500 cSt at 100°C, viscosity index of 185, flash point of 185°C, and pour point of -6°C. These properties showed that microalgae lipid could be used as potential feedstock for biolubricant production.

  18. Bio-conversion rate and optimum harvest intervals for Moina australiensis using digested piggery effluent and Chlorella vulgaris as a food source.

    PubMed

    Ward, A J; Kumar, M S

    2010-04-01

    The bio-conversion rate of Moina australiensis fed with Chlorella vulgaris grown on digested piggery effluent at three different feeding rates was determined and a 2, 3 and 4-day harvest interval strategy was investigated. This study indicates that C. vulgaris is a suitable food source for M. australiensis. A significant difference (P < or = 0.001) in the feeding rate against mean total populations was found among treatments. The increase in the amount of algae fed accelerated the production rate, and the population density peaked faster in the high C. vulgaris fed treatment. The BCR calculated from this experiment indicates that for every 1000 mg of C. vulgaris fed there was an increase of 437.9 mg of M. australiensis biomass produced. A significant difference (P < or = 0.001) in biomass production among the different harvest interval treatments was observed. The 2-day harvest interval treatment produced 7.78 g of M. australiensis followed by 6.89 g in the 3 day and 5.01 g in the 4-day harvest interval treatment. This study provides strong evidence that M. australiensis can utilise the bacterial blooms and bio-films associated with digested piggery effluent as a food source.

  19. Elimination of bicarbonate interference in the binding of U(VI) in mill-waters to freeze-dried Chlorella vulgaris

    SciTech Connect

    Greene, B.; Henzl, M.T.; Hosea, J.M.; Darnall, D.W.

    1986-01-01

    Freeze-dried preparations of Chlorella vulgaris will accumulate U(Vl) from alkaline, bicarbonate-containing waters collected from uranium mill process streams, provided that the pH is pre-adjusted to between 4.0 and 6.0. Bicarbonate ion complexes the uranyl ion in these waters and seriously interferes with the binding of U(Vl) to the algal cells at pH values above 6.0. No binding of U(Vl) to the algae occurred at the natural pH of 8.0 when Chlorella vulgaris was suspended in untreated mull-waters containing up to 2.5 x 10/sup -4/M U(Vl). However, when the pH of these waters was lowered from 8.0 to near 5.0, with nitric acid, nearly quantitative binding of U(Vl) to the alga was achieved. Binding is rapid and largely unaffected by ions including Na/sup +/, Cl/sup -/, NO/sub 3//sup -/, /sup -/OAc, and SO/sub 4//sup 2 -/. Our results indicate that provided steps are taken to eliminate bicarbonate interference, such as adjustment of the pH to near 5.0, dried algal biomass could prove useful for the removal and recovery of U(Vl) from high carbonate-containing waters.

  20. Crystallization and preliminary X-ray diffraction analysis of the homing endonuclease I-CvuI from Chlorella vulgaris in complex with its target DNA

    PubMed Central

    Redondo, Pilar; Merino, Nekane; Villate, Maider; Blanco, Francisco J.; Montoya, Guillermo; Molina, Rafael

    2014-01-01

    Homing endonucleases are highly specific DNA-cleaving enzymes that recognize long stretches of DNA. The engineering of these enzymes provides novel instruments for genome modification in a wide range of fields, including gene targeting, by inducing specific double-strand breaks. I-CvuI is a homing endonuclease from the green alga Chlorella vulgaris. This enzyme was purified after overexpression in Escherichia coli. Crystallization experiments of I-CvuI in complex with its DNA target in the presence of Mg2+ yielded crystals suitable for X-ray diffraction analysis. The crystals belonged to the orthorhombic space group P212121, with unit-cell parameters a = 62.83, b = 83.56, c = 94.40 Å. The self-rotation function and the Matthews coefficient suggested the presence of one protein–DNA complex per asymmetric unit. The crystals diffracted to a resolution limit of 1.9 Å using synchrotron radiation. PMID:24637769

  1. Pretreatment of poultry manure anaerobic-digested effluents by electrolysis, centrifugation and autoclaving process for Chlorella vulgaris growth and pollutants removal.

    PubMed

    Wang, Mengzi; Wu, Yu; Li, Baoming; Dong, Renjie; Lu, Haifeng; Zhou, Hongde; Cao, Wei

    2015-01-01

    Different pretreatments (electrolysis, centrifugation and autoclaving) coupled with Chlorella vulgaris biological system was used for the treatment of poultry manure anaerobic-digested effluents. The pretreated effluents were used as the growth medium for algal cultivation. The pollutant removal efficiencies of the combined treatments were determined. Electrochemical pretreatment can efficiently remove the ammonia (NH4+), total phosphorus (TP), total organic carbon (TOC), total carbon (TC), turbidity and bacteria in the digested effluents. About 100.0% NH4+, turbidity and bacteria, 97.6% TP, 81.5% TOC and 96.6% inorganic carbon were removed by 5-h electrochemical treatment. The maximal algal biomass accumulation (0.53 g L(-1)) was obtained from culture in the effluents pretreated with 2-h electrolysis. The pollutants removal amounts by the combination of electrolysis and biological treatment were much higher than the other combinations.

  2. Production of Chlorella vulgaris as a source of essential fatty acids in a tubular photobioreactor continuously fed with air enriched with CO2 at different concentrations.

    PubMed

    Ortiz Montoya, Erika Y; Casazza, Alessandro A; Aliakbarian, Bahar; Perego, Patrizia; Converti, Attilio; de Carvalho, João C Monteiro

    2014-01-01

    To reduce CO2 emissions and simultaneously produce biomass rich in essential fatty acids, Chlorella vulgaris CCAP 211 was continuously grown in a tubular photobioreactor using air alone or air enriched with CO2 as the sole carbon source. While on one hand, nitrogen-limited conditions strongly affected biomass growth, conversely, they almost doubled its lipid fraction. Under these conditions using air enriched with 0, 2, 4, 8, and 16% (v/v) CO2 , the maximum biomass concentration was 1.4, 5.8, 6.6, 6.8, and 6.4 gDB L(-1) on a dry basis, the CO2 consumption rate 62, 380, 391, 433, and 430 mgCO2 L(-1) day(-1) , and the lipid productivity 3.7, 23.7, 24.8, 29.5, and 24.4 mg L(-1) day(-1) , respectively. C. vulgaris was able to grow effectively using CO2 -enriched air, but its chlorophyll a (3.0-3.5 g 100gDB (-1) ), chlorophyll b (2.6-3.0 g 100gDB (-1) ), and lipid contents (10.7-12.0 g 100gDB (-1) ) were not significantly influenced by the presence of CO2 in the air. Most of the fatty acids in C. vulgaris biomass were of the saturated series, mainly myristic, palmitic, and stearic acids, but a portion of no less than 45% consisted of unsaturated fatty acids, and about 80% of these were high added-value essential fatty acids belonging to the ω3 and ω6 series. These results highlight that C. vulgaris biomass could be of great importance for human health when used as food additive or for functional food production.

  3. The Effect of Copper and Selenium Nanocarboxylates on Biomass Accumulation and Photosynthetic Energy Transduction Efficiency of the Green Algae Chlorella Vulgaris

    NASA Astrophysics Data System (ADS)

    Mykhaylenko, Natalia F.; Zolotareva, Elena K.

    2017-02-01

    Nanoaquachelates, the nanoparticles with the molecules of water and/or carboxylic acids as ligands, are used in many fields of biotechnology. Ultra-pure nanocarboxylates of microelements are the materials of spatial perspective. In the present work, the effects of copper and selenium nanoaquachelates carboxylated with citric acid on biomass accumulation of the green algae Chlorella vulgaris were examined. Besides, the efficiency of the reactions of the light stage of photosynthesis was estimated by measuring chlorophyll a fluorescence. The addition of 0.67-4 mg L-1 of Cu nanocarboxylates resulted in the increase in Chlorella biomass by ca. 20%; however, their concentrations ranging from 20 to 40 mg L-1 strongly inhibited algal growth after the 12th day of cultivation. Se nanocarboxylates at 0.4-4 mg L-1 concentrations also stimulated the growth of C. vulgaris, and the increase in biomass came up to 40-45%. The addition of Se nanocarboxylates at smaller concentrations (0.07 or 0.2 mg L-1) at first caused the retardation of culture growth, but that effect disappeared after 18-24 days of cultivation. The addition of 2-4 mg L-1 of Cu nanocarboxylates or 0.4-4 mg L-1 of Se nanocarboxylates caused the evident initial increase in such chlorophyll a fluorescence parameters as maximal quantum yield of photosystem II photochemistry ( F v/ F m) and the quantum yield of photosystem II photochemistry in the light-adapted state ( F v'/ F m'). Photochemical fluorescence quenching coefficients declined after 24 days of growth with Cu nanocarboxylates, but they increased after 6 days of the addition of 2 or 4 mg L-1 Se nanocarboxylates. Those alterations affected the overall quantum yield of the photosynthetic electron transport in photosystem II.

  4. The effect of dietary Chlorella vulgaris supplementation on micro-organism community, enzyme activities and fatty acid profile in the rumen liquid of goats.

    PubMed

    Tsiplakou, E; Abdullah, M A M; Skliros, D; Chatzikonstantinou, M; Flemetakis, E; Labrou, N; Zervas, G

    2017-04-01

    Microalgae might be considered as an alternative source of fat and/or protein for ruminant's diets. However, changes in populations of ruminal micro-organisms associated with biohydrogenation process, methane and ammonia production in response to microalgae dietary supplementation have not been well characterized. Thus, 16 cross-bred goats were divided into two groups. Each goat of both groups was fed individually with alfalfa hay and concentrates separately. The concentrates of the control group had no microalgae while those of the treated group were supplemented with 10 g lyophilized Chlorella vulgaris/kg concentrate (chlor). On the 30th experimental day, samples of rumen fluid were collected for microbial DNA extraction, fatty acid profile and enzyme activity analyses. The results showed that the chlor diet compared with the control increased significantly the populations of Methanosphaera stadtmanae, Methanobrevibacter ruminantium and Methanogens bacteria and protozoa in the rumen of goats. A significant reduction in the cellulase activity and in the abundance of Ruminococcus albus, and a significant increase in the protease activity and in the abundance of Clostridium sticklandii in the rumen liquid of goats fed with the chlor diet, compared with the control, were found. Chlorella vulgaris supplementation promoted the formation of trans C18:1 , trans-11 C18:1 and monounsaturated fatty acids (MUFA), while the proportions of C18:0 and long-chain fatty acids (LCFA) reduced significantly in the rumen liquid of goats. This shift in ruminal biohydrogenation pathway was accompanied by a significant increase in Butyrivibrio fibrisolvens trans C18:1 -producing bacteria. In conclusion, the supplementation of diets with microalgae needs further investigation because it enhances the populations of methane-producing bacteria and protozoa.

  5. Efficiency assessment and pH effect in removing nitrogen and phosphorus by algae-bacteria combined system of Chlorella vulgaris and Bacillus licheniformis.

    PubMed

    Liang, Zhijie; Liu, Yan; Ge, Fei; Xu, Yin; Tao, Nengguo; Peng, Fang; Wong, Minghung

    2013-08-01

    To achieve better removal of NH4(+) and TP in wastewater, a new algae-bacteria combined system of Chlorella vulgaris and Bacillus licheniformis was investigated in a 6-d experiment. The results showed that 78% of NH4(+) could be removed in the combined system, while 29% in single algae system and only 1% in single bacteria system. Approximately 92% of TP was removed in the combined system, compared with 55% and 78% in single algae and bacteria system, respectively. B. licheniformis was proven to be a growth-promoting bacterium for C. vulgaris by comparing Chl a concentrations in the single and combined systems. In the removal process, pH of the combined system was observed to reduce significantly from 7.0 to 3.5. Whereas with pH regulated to 7.0, higher removal efficiencies of NH4(+) (86%) and TP (93%) were achieved along with the recovery of algal cells and the increase of Chl a. These results suggest that nutrients in wastewater can be removed efficiently by the algae-bacteria combined system and pH control is crucial in the process.

  6. Effects of various LED light wavelengths and light intensity supply strategies on synthetic high-strength wastewater purification by Chlorella vulgaris.

    PubMed

    Yan, Cheng; Zhao, Yongjun; Zheng, Zheng; Luo, Xingzhang

    2013-09-01

    Chemical fertilizer agricultural wastewater is a typical high-strength wastewater that has dramatically triggered numerous environmental problems in China. The Chlorella vulgaris microalgae biological wastewater treatment system used in this study can effectively decontaminate the high-strength carbon and nitrogen wastewater under an optimum light wavelength and light intensity supply strategy. The descending order of both the dry weight for C. vulgaris reproduction and wastewater nutrient removal efficiency is red > white > yellow > purple > blue > green, which indicates that red light is the optimum light wavelength. Furthermore, rather than constant light, optimal light intensity is used for the incremental light intensity strategy. The phases for the optimal light intensity supply strategy are as follows: Phase 1 from 0 to 48 h at 800 μmol m(-2) s(-1); Phase 2 from 48 to 96 h at 1,200 μmol m(-2) s(-1); and Phase 3 from 96 to 144 h at 1,600 μmol m(-2) s(-1). Additionally, the optimal cultivation time is 144 h.

  7. Nitrogen starvation strategies and photobioreactor design for enhancing lipid content and lipid production of a newly isolated microalga Chlorella vulgaris ESP-31: implications for biofuels.

    PubMed

    Yeh, Kuei-Ling; Chang, Jo-Shu

    2011-11-01

    Microalgae are recognized for serving as a sustainable source for biodiesel production. This study investigated the effect of nitrogen starvation strategies and photobioreactor design on the performance of lipid production and of CO(2) fixation of an indigenous microalga Chlorella vulgaris ESP-31. Comparison of single-stage and two-stage nitrogen starvation strategies shows that single-stage cultivation on basal medium with low initial nitrogen source concentration (i.e., 0.313 g/L KNO(3)) was the most effective approach to enhance microalgal lipid production, attaining a lipid productivity of 78 mg/L/d and a lipid content of 55.9%. The lipid productivity of C. vulgaris ESP-31 was further upgraded to 132.4 mg/L/d when it was grown in a vertical tubular photobioreactor with a high surface to volume ratio of 109.3 m(2)/m(3) . The high lipid productivity was also accompanied by fixation of 6.36 g CO(2) during the 10-day photoautotrophic growth with a CO(2) fixation rate of 430 mg/L/d. Analysis of fatty acid composition of the microalgal lipid indicates that over 65% of fatty acids in the microalgal lipid are saturated [i.e., palmitic acid (C16:0) and stearic acid (C18:0)] and monounsaturated [i.e., oleic acid (C18:1)]. This lipid quality is suitable for biodiesel production.

  8. Enzymatic pretreatment of Chlorella vulgaris for biogas production: Influence of urban wastewater as a sole nutrient source on macromolecular profile and biocatalyst efficiency.

    PubMed

    Mahdy, Ahmed; Ballesteros, Mercedes; González-Fernández, Cristina

    2016-01-01

    Two biocatalysts, namely carbohydrases and proteases, were assessed for organic matter solubilisation and methane yield enhancement of microalgae biomass. This study evidenced Chlorella vulgaris carbohydrate accumulation (40% on VSS basis) when grown in urban wastewater. Despite of the carbohydrate prevailing fraction, protease pretreatment showed higher organic matter hydrolysis efficiency (54%). Microscopic observation revealed that carbohydrases affected slightly the cell wall while protease was not selective to wall constituents. Raw and pretreated biomass was digested at 1.5 kg tCOD m(-3) day(-1) organic loading rate (OLR1) and 20 days hydraulic retention time (HRT). The highest methane yield (137 mL CH4 g COD in(-1)) was achieved in the reactor fed with protease pretreated C. vulgaris. Additionally, anaerobic digestion was conducted at OLR2 (3 kg tCOD m(-3) day(-1)) and HRT (15 days). When compared to raw biomass, methane yield increased 5- and 6.3-fold at OLR1 and OLR2, respectively. No inhibitors were detected during the anaerobic digestion.

  9. Amelioration of arsenic toxicity in rice: Comparative effect of inoculation of Chlorella vulgaris and Nannochloropsis sp. on growth, biochemical changes and arsenic uptake.

    PubMed

    Upadhyay, A K; Singh, N K; Singh, R; Rai, U N

    2016-02-01

    The present study was conducted to assess the responses of rice (Oryza sativa L. var. Triguna) by inoculating alga; Chlorella vulgaris and Nannochlropsis sp. supplemented with As(III) (50µM) under hydroponics condition. Results showed that reduced growth variables and protein content in rice plant caused by As toxicity were restored in the algae inoculated plants after 7d of treatment. The rice plant inoculated with Nannochloropsis sp. exhibited a better response in terms of increased root, shoot length and biomass than C. vulgaris under As(III) treatment. A significant reduction in cellular toxicity (thiobarbituric acid reactive substances) and antioxidant enzyme (SOD, APX and GR) activities were observed in algae inoculated rice plant under As(III) treatment in comparison to uninoculated rice. In addition, rice treated with As(III), accumulated 35.05mgkg(-1)dw arsenic in the root and 29.96mgkg(-1)dw in the shoot. However, lower accumulation was observed in As(III) treated rice inoculated with C. vulgaris (24.09mg kg(-1)dw) and Nannochloropsis sp. (20.66mgkg(-1)dw) in the roots, while in shoot, it was 20.10mgkg(-1)dw and 11.67mgkg(-1)dw, respectively. Results demonstrated that application of these algal inoculum ameliorates toxicity and improved tolerance in rice through reduced As uptake and modulating antioxidant enzymes. Thus, application of algae could provide a low-cost and eco-friendly mitigation approach to reduce accumulation of arsenic in edible part of rice as well as higher yield in the As contaminated agricultural field.

  10. Fast algal eco-toxicity assessment: Influence of light intensity and exposure time on Chlorella vulgaris inhibition by atrazine and DCMU.

    PubMed

    Camuel, Alexandre; Guieysse, Benoit; Alcántara, Cynthia; Béchet, Quentin

    2017-06-01

    In order to develop a rapid assay suitable for algal eco-toxicity assessments under conditions representative of natural ecosystems, this study evaluated the short-term (<1h) response of algae exposed to atrazine and DCMU using oxygen productivity measurements. When Chlorella vulgaris was exposed to these herbicides under 'standard' low light intensity (as prescribed by OECD201 guideline), the 20min-EC50 values recorded via oxygen productivity (atrazine: 1.32±0.07μM; DCMU: 0.31±0.005μM) were similar the 96-h EC50 recorded via algal growth (atrazine: 0.56μM; DCMU: 0.41μM), and within the range of values reported in the literature. 20min-EC50 values increased by factors of 3.0 and 2.1 for atrazine and DCMU, respectively, when light intensity increased from 60 to 1400μmolm(-2)s(-1) of photosynthetically active radiation, or PAR. Further investigation showed that exposure time significantly also impacted the sensitivity of C. vulgaris under high light intensity (>840μmolm(-2)s(-1) as PAR) as the EC50 for atrazine and DCMU decreased by up to 6.2 and 2.1 folds, respectively, after 50min of exposure at a light irradiance of 1400μmolm(-2)s(-1) as PAR. This decrease was particularly marked at high light intensities and low algae concentrations and is explained by the herbicide disruption of the electron transfer chain triggering photo-inhibition at high light intensities. Eco-toxicity assessments aiming to understand the potential impact of toxic compounds on natural ecosystems should therefore be performed over sufficient exposure times (>20min for C. vulgaris) and under light intensities relevant to these ecosystems.

  11. Combined effect of concentrations of algal food (Chlorella vulgaris) and salt (sodium chloride) on the population growth of Brachionus calyciflorus and Brachionus patulus (Rotifera).

    PubMed

    Peredo-Alvarez, Víctor M; Sarma, S S; Nandini, S

    2003-06-01

    Salinity is an important variable influencing the density and diversity of rotifers. Studies on salt tolerance of rotifers have so far concentrated on euryhaline species while very little information is available on non-euryhaline taxa. In the present work, we have evaluated the combined effects of Chlorella vulgaris and sodium chloride on the population growth of two freshwater rotifers B. calyciflorus and B. patulus. A 24 hr acute tolerance test using NaCl revealed that B. calyciflorus was more resistant (LC50 = 3.75 +/- 0.04 g l-1) than B. patulus (2.14 +/- 0.09 g l-1). The maximal population density (mean +/- standard error) for B. calyciflorus in the control at 4.5 x 10(6) cells ml-1 (algal level) was 80 +/- 5 ind. ml-1, which was nearly a fifth of the one for B. patulus (397 +/- 7 ind. ml-1) under comparable conditions. Data on population growth revealed that regardless of salt concentration, the density of B. calyciflorus increased with increasing food levels, while for B. patulus, this trend was evident only in the controls. Regardless of salt concentration and algal food level, the day of maximal population density was lower (4 +/- 0.5 days) for B. calyciflorus than for B. patulus (11 +/- 1 day). The highest rates of population increase (r values) for B. calyciflorus and B. patulus were 0.429 +/- 0.012 and 0.367 +/- 0.004, respectively, recorded at 4.5 x 10(6) cells ml-1 of Chlorella in the controls. The protective role of algae in reducing the effect of salt stress was more evident in B. calyciflorus than B. patulus.

  12. A Comparative Study on the Effects of Millisecond- and Microsecond-Pulsed Electric Field Treatments on the Permeabilization and Extraction of Pigments from Chlorella vulgaris.

    PubMed

    Luengo, Elisa; Martínez, Juan Manuel; Coustets, Mathilde; Álvarez, Ignacio; Teissié, Justin; Rols, Marie-Pierre; Raso, Javier

    2015-10-01

    The interdependencies of the two main processing parameters affecting "electroporation" (electric field strength and pulse duration) while using pulse duration in the range of milliseconds and microseconds on the permeabilization, inactivation, and extraction of pigments from Chlorella vulgaris was compared. While irreversible "electroporation" was observed above 4 kV/cm in the millisecond range, electric field strengths of ≥10 kV/cm were required in the microseconds range. However, to cause the electroporation of most of the 90 % of the population of C. vulgaris in the millisecond (5 kV/cm, 20 pulses) or microsecond (15 kV/cm, 25 pulses) range, the specific energy that was delivered was lower for microsecond treatments (16.87 kJ/L) than in millisecond treatments (150 kJ/L). In terms of the specific energy required to cause microalgae inactivation, treatments in the microsecond range also resulted in greater energy efficiency. The comparison of extraction yields in the range of milliseconds (5 kV, 20 ms) and microseconds (20, 25 pulses) under the conditions in which the maximum extraction was observed revealed that the improvement in the carotenoid extraction was similar and chlorophyll a and b extraction was slightly higher for treatments in the microsecond range. The specific energy that was required for the treatment in the millisecond range (150 kJ/L) was much higher than those required in the microsecond range (30 kJ/L). The comparison of the efficacy of both types of pulses on the extraction enhancement just after the treatment and after a post-pulse incubation period seemed to indicate that PEF in the millisecond range created irreversible alterations while, in the microsecond range, the defects were a dynamic structure along the post-pulse time that caused a subsequent increment in the extraction yield.

  13. Sensing of phosphates by using luminescent Eu(III) and Tb(III) complexes: application to the microalgal cell Chlorella vulgaris.

    PubMed

    Nadella, Sandeep; Sahoo, Jashobanta; Subramanian, Palani S; Sahu, Abhishek; Mishra, Sandhya; Albrecht, Markus

    2014-05-12

    Phenanthroline-based chiral ligands L(1) and L(2) as well as the corresponding Eu(III) and Tb(III) complexes were synthesized and characterized. The coordination compounds show red and green emission, which was explored for the sensing of a series of anions such as F(-), Cl(-), Br(-), I(-), NO3(-), NO2(-), HPO4(2-), HSO4(-), CH3COO(-), and HCO3(-). Among the anions, HPO4(2-) exhibited a strong response in the emission property of both europium(III) and terbium(III) complexes. The complexes showed interactions with the nucleoside phosphates adenosine triphosphate (ATP), adenosine diphosphate (ADP), and adenosine monophosphate (AMP). Owing to this recognition, these complexes have been applied as staining agents in the microalgal cell Chlorella vulgaris. The stained microalgal cells were monitored through fluorescence microscopy and scanning electron microscopy. Initially, the complexes bind to the outer cell wall and then enter the cell wall through holes in which they probably bind to phospholipids. This leads to a quenching of the luminescence properties.

  14. Mixed culture of oleaginous yeast Rhodotorula glutinis and microalga Chlorella vulgaris for lipid production from industrial wastes and its use as biodiesel feedstock.

    PubMed

    Cheirsilp, Benjamas; Suwannarat, Warangkana; Niyomdecha, Rujira

    2011-07-01

    A mixed culture of oleaginous yeast Rhodotorula glutinis and microalga Chlorella vulgaris was performed to enhance lipid production from industrial wastes. These included effluent from seafood processing plant and molasses from sugar cane plant. In the mixed culture, the yeast grew faster and the lipid production was higher than that in the pure cultures. This could be because microalga acted as an oxygen generator for yeast, while yeast provided CO(2) to microalga and both carried out the production of lipids. The optimal conditions for lipid production by the mixed culture were as follows: ratio of yeast to microalga at 1:1; initial pH at 5.0; molasses concentration at 1%; shaking speed at 200 rpm; and light intensity at 5.0 klux under 16:8 hours light and dark cycles. Under these conditions, the highest biomass of 4.63±0.15 g/L and lipid production of 2.88±0.16 g/L were obtained after five days of cultivation. In addition, the plant oil-like fatty acid composition of yeast and microalgal lipids suggested their high potential for use as biodiesel feedstock.

  15. Investigation of simultaneous biosorption of copper(II) and chromium(VI) on dried Chlorella vulgaris from binary metal mixtures: Application of multicomponent adsorption isotherms

    SciTech Connect

    Aksu, Z.; Acikel, U.; Kutsal, T.

    1999-02-01

    Although the biosorption of single metal ions to various kinds of microorganisms has been extensively studied and the adsorption isotherms have been developed for only the single metal ion situation, very little attention has been given to the bioremoval and expression of adsorption isotherms of multimetal ions systems. In this study the simultaneous biosorption of copper(II) and chromium(VI) to Chlorella vulgaris from a binary metal mixture was studied and compared with the single metal ion situation in a batch stirred system. The effects of pH and single- and dual-metal ion concentrations on the equilibrium uptakes were investigated. In previous studies the optimum biosorption pH had been determined as 4.0 for copper(II) and as 2.0 for chromium(VI). Multimetal ion biosorption studies were performed at these two pH values. It was observed that the equilibrium uptakes of copper(II) or chromium(VI) ions were changed due to the biosorption pH and the presence of other metal ions. Adsorption isotherms were developed for both single- and dual-metal ions systems at these two pH values, and expressed by the mono- and multicomponent Langmuir and Freundlich adsorption models. Model parameters were estimated by nonlinear regression. It was seen that the adsorption equilibrium data fitted very well to the competitive Freundlich model in the concentration ranges studied.

  16. Envelopment-Internalization Synergistic Effects and Metabolic Mechanisms of Graphene Oxide on Single-Cell Chlorella vulgaris Are Dependent on the Nanomaterial Particle Size.

    PubMed

    Ouyang, Shaohu; Hu, Xiangang; Zhou, Qixing

    2015-08-19

    The interactions between nanomaterials and cells are fundamental in biological responses to nanomaterials. However, the size-dependent synergistic effects of envelopment and internalization as well as the metabolic mechanisms of nanomaterials have remained unknown. The nanomaterials tested here were larger graphene oxide nanosheets (GONS) and small graphene oxide quantum dots (GOQD). GONS intensively entrapped single-celled Chlorella vulgaris, and envelopment by GONS reduced the cell permeability. In contrast, GOQD-induced remarkable shrinkage of the plasma membrane and then enhanced cell permeability through strong internalization effects such as plasmolysis, uptake of nanomaterials, an oxidative stress increase, and inhibition of cell division and chlorophyll biosynthesis. Metabolomics analysis showed that amino acid metabolism was sensitive to nanomaterial exposure. Shrinkage of the plasma membrane is proposed to be linked to increases in the isoleucine levels. The inhibition of cell division and chlorophyll a biosynthesis was associated with decreases in aspartic acid and serine, the precursors of chlorophyll a. The increases in mitochondrial membrane potential loss and oxidative stress were correlated with an increase in linolenic acid. The above metabolites can be used as indicators of the corresponding biological responses. These results enhance our systemic understanding of the size-dependent biological effects of nanomaterials.

  17. Effect of light intensity on the degree of ammonia toxicity on PSII activity of Arthrospira platensis and Chlorella vulgaris.

    PubMed

    Markou, Giorgos; Muylaert, Koenraad

    2016-09-01

    Herein the effect of increasing light intensity on the degree of ammonia toxicity and its impact on the photosynthetic performance of Arthrospira and Chlorella was investigated using Chl fluorescence as a technique to characterize their photosystem II (PSII) activity. The results revealed that the increase of light intensity amplifies the ammonia toxicity on PSII. Chl fluorescence transients shown that at a given free ammonia (FA) concentration (100mg-N/L), the photochemistry potential decreased by increasing light intensity. The inhibition of the PSII was not reversible either by re-incubating the cells under dark or under decreased FA concentration. Moreover, the decrease of photochemical and non-photochemical quenching (NPQ) of fluorescence suggest that ammonia toxicity decreases the open available PSII centers, as well the inability of PSII to transfer the generated electrons beyond QA. The collapse of NPQ suggests that ammonia toxicity inhibits the photoprotection mechanism(s) and hence renders PSII more sensitive to photoinhibition.

  18. Effects of pH control and concentration on microbial oil production from Chlorella vulgaris cultivated in the effluent of a low-cost organic waste fermentation system producing volatile fatty acids.

    PubMed

    Cho, Hyun Uk; Kim, Young Mo; Choi, Yun-Nam; Xu, Xu; Shin, Dong Yun; Park, Jong Moon

    2015-05-01

    The objective of this study was to investigate the feasibility of applying volatile fatty acids (VFAs) produced from low-cost organic waste to the major carbon sources of microalgae cultivation for highly efficient biofuel production. An integrated process that consists of a sewage sludge fermentation system producing VFAs (SSFV) and mixotrophic cultivation of Chlorella vulgaris (C. vulgaris) was operated to produce microbial lipids economically. The effluents from the SSFV diluted to different concentrations at the level of 100%, 50%, and 15% were prepared for the C. vulgaris cultivation and the highest biomass productivity (433±11.9 mg/L/d) was achieved in the 100% culture controlling pH at 7.0. The harvested biomass included lipid contents ranging from 12.87% to 20.01% under the three different effluent concentrations with and without pH control. The composition of fatty acids from C. vulgaris grown on the effluents from the SSFV complied with the requirements of high-quality biodiesel. These results demonstrated that VFAs produced from the SSFV are favorable carbon sources for cultivating C. vulgaris.

  19. Comparative study of the trophic transfer of two mercury compounds--HgCl/sub 2/ and CH/sub 3/HgCl--between Chlorella vulgaris and Daphnia magna. Influence of temperature

    SciTech Connect

    Baudou, A.; Ribeyre, F.

    1981-12-01

    A comparative study is presented of the transfer of HgCl/sub 2/ and CH/sub 3/HgCl between a species representative of the ''producer'' level -- Chlorella vulgaris -- and a primary consumer -- Daphnia magna. The experiment was carried out at two temperatures, 10 and 18/sup 0/C, and the concentration of metal in the environment was 1 ..mu..g.l/sup -1/ (1 ppb). Results seem to indicate that the two contaminants, which are first introduced into the environment and then fixed by the unicellular algae, retain their specific property of crossing the digestive barrier of the consumer link.

  20. Nitrous oxide (N2O) production in axenic Chlorella vulgaris cultures: evidence, putative pathways, and potential environmental impacts

    NASA Astrophysics Data System (ADS)

    Guieysse, B.; Plouviez, M.; Coilhac, M.; Cazali, L.

    2013-06-01

    Using antibiotic assays and genomic analysis, this study demonstrates nitrous oxide (N2O) is generated from axenic C. vulgaris cultures. In batch assays, this production is magnified under conditions favoring intracellular nitrite accumulation, but repressed when nitrate reductase (NR) activity is inhibited. These observations suggest N2O formation in C. vulgaris might proceed via NR-mediated nitrite reduction into nitric oxide (NO) acting as N2O precursor via a pathway similar to N2O formation in bacterial denitrifiers, although NO reduction to N2O under oxia remains unproven in plant cells. Alternatively, NR may reduce nitrite to nitroxyl (HNO), the latter being known to dimerize to N2O under oxia. Regardless of the precursor considered, an NR-mediated nitrite reduction pathway provides a unifying explanation for correlations reported between N2O emissions from algae-based ecosystems and NR activity, nitrate concentration, nitrite concentration, and photosynthesis repression. Moreover, these results indicate microalgae-mediated N2O formation might significantly contribute to N2O emissions in algae-based ecosystems. These findings have profound implications for the life cycle analysis of algae biotechnologies and our understanding of the global biogeochemical nitrogen cycle.

  1. Probing the interaction induced conformation transitions in acid phosphatase with cobalt ferrite nanoparticles: Relation to inhibition and bio-activity of Chlorella vulgaris acid phosphatase.

    PubMed

    Ahmad, Farooq; Zhou, Xing; Yao, Hongzhou; Zhou, Ying; Xu, Chao

    2016-09-01

    The present study explored the interaction and kinetics of cobalt ferrite nanoparticles (NPs) with acid phosphatase (ACP) by utilizing diverse range of spectroscopic techniques. The results corroborate, the CoFe2O4 NPs cause fluorescence quenching in ACP by static quenching mechanism. The negative values of van't Hoff thermodynamic expressions (ΔH=-0.3293Jmol(-1)K(-1) and ΔG=-3.960kJmol(-1)K(-1)) corroborate the spontaneity and exothermic nature of static quenching. The positive value of ΔS (13.2893Jmol(-1)K(-1)) corroborate that major contributors of higher and stronger binding affinity among CoFe2O4 NPs with ACP were electrostatic. In addition, FTIR, UV-CD, UV-vis spectroscopy and three dimensional fluorescence (3D) techniques confirmed that CoFe2O4 NPs binding induces microenvironment perturbations leading to secondary and tertiary conformation changes in ACP to a great extent. Furthermore, synchronous fluorescence spectroscopy (SFS) affirmed the comparatively significant changes in microenvironment around tryptophan (Trp) residue by CoFe2O4 NPs. The effect of CoFe2O4 NPs on the activation kinetics of ACP was further examined in Chlorella vulgaris. Apparent Michaelis constant (Km) values of 0.57 and 26.5mM with activation energy values of 0.538 and 3.428kJmol(-1) were determined without and with 200μM CoFe2O4 NPs. Apparent Vmax value of -7Umml(-1) corroborate that enzyme active sites were completely captured by the NPs leaving no space for the substrate. The results confirmed that CoFe2O4 NPs ceased the activity by unfolding of ACP enzyme. This suggests CoFe2O4 NPs perturbed the enzyme activity by transitions in conformation and hence the metabolic activity of ACP. This study provides the pavement for novel and simple approach of using sensitive biomarkers for sensing NPs in environment.

  2. Experimental study and thermodynamic modeling for determining the effect of non-polar solvent (hexane)/polar solvent (methanol) ratio and moisture content on the lipid extraction efficiency from Chlorella vulgaris.

    PubMed

    Malekzadeh, Mohammad; Abedini Najafabadi, Hamed; Hakim, Maziar; Feilizadeh, Mehrzad; Vossoughi, Manouchehr; Rashtchian, Davood

    2016-02-01

    In this research, organic solvent composed of hexane and methanol was used for lipid extraction from dry and wet biomass of Chlorella vulgaris. The results indicated that lipid and fatty acid extraction yield was decreased by increasing the moisture content of biomass. However, the maximum extraction efficiency was attained by applying equivolume mixture of hexane and methanol for both dry and wet biomass. Thermodynamic modeling was employed to estimate the effect of hexane/methanol ratio and moisture content on fatty acid extraction yield. Hansen solubility parameter was used in adjusting the interaction parameters of the model, which led to decrease the number of tuning parameters from 6 to 2. The results indicated that the model can accurately estimate the fatty acid recovery with average absolute deviation percentage (AAD%) of 13.90% and 15.00% for the two cases of using 6 and 2 adjustable parameters, respectively.

  3. Measurement of Lipid Accumulation in Chlorella vulgaris via Flow Cytometry and Liquid-State ¹H NMR Spectroscopy for Development of an NMR-Traceable Flow Cytometry Protocol

    PubMed Central

    Bono Jr., Michael S.; Garcia, Ravi D.; Sri-Jayantha, Dylan V.; Ahner, Beth A.; Kirby, Brian J.

    2015-01-01

    In this study, we cultured Chlorella vulgaris cells with a range of lipid contents, induced via nitrogen starvation, and characterized them via flow cytometry, with BODIPY 505/515 as a fluorescent lipid label, and liquid-state 1H NMR spectroscopy. In doing so, we demonstrate the utility of calibrating flow cytometric measurements of algal lipid content using triacylglyceride (TAG, also known as triacylglycerol or triglyceride) content per cell as measured via quantitative 1H NMR. Ensemble-averaged fluorescence of BODIPY-labeled cells was highly correlated with average TAG content per cell measured by bulk NMR, with a linear regression yielding a linear fit with r2 = 0.9974. This correlation compares favorably to previous calibrations of flow cytometry protocols to lipid content measured via extraction, and calibration by NMR avoids the time and complexity that is generally required for lipid quantitation via extraction. Flow cytometry calibrated to a direct measurement of TAG content can be used to investigate the distribution of lipid contents for cells within a culture. Our flow cytometry measurements showed that Chlorella vulgaris cells subjected to nitrogen limitation exhibited higher mean lipid content but a wider distribution of lipid content that overlapped the relatively narrow distribution of lipid content for replete cells, suggesting that nitrogen limitation induces lipid accumulation in only a subset of cells. Calibration of flow cytometry protocols using direct in situ measurement of TAG content via NMR will facilitate rapid development of more precise flow cytometry protocols, enabling investigation of algal lipid accumulation for development of more productive algal biofuel feedstocks and cultivation protocols. PMID:26267664

  4. Bioaccumulation of arsenic by freshwater algae and the application to the removal of inorganic arsenic from an aqueous phase. Part II. By Chlorella vulgaris isolated from arsenic-polluted environment

    SciTech Connect

    Maeda, S.; Nakashima, S.; Takeshita, T.; Higashi, S.

    1985-01-01

    Green algae, Chlorella vulgaris Beijerinck var. vulgaris, isolated from an arsenic-polluted environment, was examined for the effects of arsenic levels, arsenic valence, temperature illumination intensity, phosphate levels, metabolism inhibitors, heat treatment on the growth, and arsenic bioaccumulation. The following conclusions were reached from the experimental results: (a) The growth of the cell increased with an increase of arsenic(V) levels of the medium up to 1000 ppm, and the cell survived even at 10,000 ppm; (b) The arsenic bioaccumulation increased with an increase of the arsenic level. The maximum accumulation of arsenic was about 50,000 ..mu..g As/g dry cell; (c) The growth decreased with an increase of the arsenic(III) level and the cell was cytolyzed at levels higher than 40 ppm; (d) No arsenic(V) was bioaccumulated by a cell which had been pretreated with dinitrophenol (respiratory inhibitor) or with heat. Little effect of NaN/sub 3/ (photosynthesis inhibitor) on the bioaccumulation was observed. 8 references, 2 figures, 6 tables.

  5. Uptake and accumulation of exogenous docosahexaenoic acid by Chlorella.

    PubMed

    Hayashi, M; Yukino, T; Maruyama, I; Kido, S; Kitaoka, S

    2001-01-01

    Tuna oil or its hydrolysate was added to a culture of Chlorella for its nutritional fortification as a feed for rotifer. Exogenous docosahexaenoic acid (DHA) in its free form was taken up by the cells of Chlorella vulgaris strain K-22 and by other strains, but tuna oil was not taken up by the cells. Accumulated DHA was found by electron microscopy in the cells in oil droplets. All strains of Chlorella used in these experiments took up exogenous DHA into the cells. It seems that the structure of the cell wall did not affect the uptake of DHA into the Chlorella cells.

  6. Effect of solvents and oil content on direct transesterification of wet oil-bearing microalgal biomass of Chlorella vulgaris ESP-31 for biodiesel synthesis using immobilized lipase as the biocatalyst.

    PubMed

    Tran, Dang-Thuan; Chen, Ching-Lung; Chang, Jo-Shu

    2013-05-01

    In this work, a one-step extraction/transesterification process was developed to directly convert wet oil-bearing microalgal biomass of Chlorella vulgaris ESP-31 into biodiesel using immobilized Burkholderia lipase as the catalyst. The microalgal biomass (water content of 86-91%; oil content 14-63%) was pre-treated by sonication to disrupt the cell walls and then directly mixed with methanol and solvent to carry out the enzymatic transesterification. Addition of a sufficient amount of solvent (hexane is most preferable) is required for the direct transesterification of wet microalgal biomass, as a hexane-to-methanol mass ratio of 1.65 was found optimal for the biodiesel conversion. The amount of methanol and hexane required for the direct transesterification process was also found to correlate with the lipid content of the microalga. The biodiesel synthesis process was more efficient and economic when the lipid content of the microalgal biomass was higher. Therefore, using high-lipid-content microalgae as feedstock appears to be desirable.

  7. Optimization of ferric chloride concentration and pH to improve both cell growth and flocculation in Chlorella vulgaris cultures. Application to medium reuse in an integrated continuous culture bioprocess.

    PubMed

    Lecina, Martí; Nadal, Gisela; Solà, Carles; Prat, Jordi; Cairó, Jordi J

    2016-09-01

    Combined effect of ferric chloride and pH on Chlorella vulgaris growth and flocculation were optimized using DoE. Afterwards, an integrated bioprocess for microalgae cultivation and harvesting conceived as a sole step was run in continuous operation mode. Microalgae concentration in a 2L-photobioreactor was about 0.5gL(-1) and the efficiency of flocculation in the coupled sedimentation tank was about 95%. Dewatered microalgae reached a biomass concentrations increase about 50-fold, whereas it was only about 0.02gL(-1) in the clarified medium. Then, the reuse of the clarified medium recovered was further evaluated. The clarified medium was reused without any further nutrient supplementation, whereas a second round of medium reuse was performed after supplementation of main nutrients (phosphate-sulfate-nitrate), micronutrients and ferric chloride. The medium reuse strategy did not affect cell growth and flocculation. Consequently, the reuse of medium reduces the nutrients requirements and the demand for water, and therefore the production costs should be reduced accordingly.

  8. Effect of pH on growth and lipid accumulation kinetics of the microalga Chlorella vulgaris grown heterotrophically under sulfur limitation.

    PubMed

    Sakarika, Myrsini; Kornaros, Michael

    2016-11-01

    The goal of the present study was to investigate the pH range that can support the growth of C. vulgaris, and, more specifically, to identify the optimal pH for the microalga's growth, under heterotrophic conditions. Furthermore, the effect of pH on the accumulation of intracellular lipids was studied. A wide range of pH values was tested using the respective buffer solutions. The optimal pH for biomass growth and lipid accumulation under sulfur limitation was found to be 7.5, resulting in maximum specific growth rate of 0.541days(-1) and maximum total lipid content of 53.43%ggDW(-1). The fatty acid composition of C. vulgaris was found to be unrelated to pH, as the lipid content did not present significant variations in the pH values tested. The fatty acid profile was mainly composed of monounsaturated fatty acids (MUFAs) with the dominant one being oleic acid (C18:1).

  9. Spectroscopic probe to contribution of physicochemical transformations in the toxicity of aged ZnO NPs to Chlorella vulgaris: new insight into the variation of toxicity of ZnO NPs under aging process.

    PubMed

    Zhang, Hong; Huang, Qing; Xu, An; Wu, Lijun

    2016-10-01

    Zinc oxide nanoparticles (ZnO NPs) are one of the most abundantly applied nanomaterials in nanotechnology-based industries and they may cause unexpected environmental and health risks with their physicochemical transformations in the environment. Currently, there is still a lack of the in-depth understanding of the toxicity of aged ZnO NPs to aquatic organisms, particularly demanding quantitative analysis of the physicochemical transformations to distinguish their contributions in the toxicity assessment. For this purpose, therefore, we initiated the study of the toxicity of aged ZnO NPs to the model aquatic microalga, i.e. Chlorella vulgaris, and with the aid of spectroscopic tools for characterization and quantification of the physicochemical transformations, we scrutinized the toxicity variations for ZnO NPs with different aging times. As a result, we found that the toxicity altered in an abnormal manner with the aging time, i.e. the toxicity of aged ZnO NPs for 30 days showed the higher toxicity to the green alga than the fresh ZnO NPs or the ZnO NPs aged for longer time (e.g. 120 and 210 days). Through spectroscopic tools such as XRD, FTIR and Raman spectroscopy, we made both the qualitative and quantitative assessments of the physicochemical changes of the ZnO NPs, and confirmed that in the early stage, the toxicity mainly stemmed from the release of zinc ions, but with longer aging time, the neoformation of the nanoparticles played the critical role, leading to the overall reduced toxicity due to the less toxic hydrozincite and zinc hydroxide in the transformed compounds.

  10. Ultraviolet and 5'fluorodeoxyuridine induced random mutagenesis in Chlorella vulgaris and its impact on fatty acid profile: a new insight on lipid-metabolizing genes and structural characterization of related proteins.

    PubMed

    Anthony, Josephine; Rangamaran, Vijaya Raghavan; Gopal, Dharani; Shivasankarasubbiah, Kumar T; Thilagam, Mary Leema J; Peter Dhassiah, Magesh; Padinjattayil, Divya Shridhar M; Valsalan, VinithKumar N; Manambrakat, Vijayakumaran; Dakshinamurthy, Sivakumar; Thirunavukkarasu, Sivaraman; Ramalingam, Kirubagaran

    2015-02-01

    The present study was aimed at randomly mutating the microalga, Chlorella vulgaris, in order to alter its cellular behaviour towards increased lipid production for efficient biodiesel production from algal biomass. Individual mutants from ultraviolet light (UV-1 (30 s exposure), UV-2 (60 s exposure) and UV-3 (90 s exposure)) and 5'fluorodeoxyuridine (5'FDU-1 (0.25 mM) and 5'FDU-2 (0.50 mM)) exposed cells were identified to explore an alternative method for lipid enhancement. A marginally significant decrease in biomass in the UV mutants; marked increase in the lipid content in UV-2 and 5'FDU-1 mutants; significant increase in saturated fatty acids level, especially in UV-2 mutant; insignificant increase in lipid production when these mutants were subjected to an additional stress of nitrogen starvation and predominantly enhanced level of unsaturated fatty acids in all the strains except UV-2 were noted. Chloroplast ultrastructural alterations and defective biosynthesis of chloroplast specific lipid constituents were observed in the mutants. Modelling of three-dimensional structures of acetyl coA carboxylase (ACCase), omega-6, plastid delta-12 and microsomal delta-12 fatty acid desaturases for the first time and ligand-interaction studies greatly substantiated our findings. A replacement of leucine by a serine residue in the acetyl coA carboxylase gene of UV-2 mutant suggests the reason behind lipid enhancement in UV-2 mutant. Higher activity of ACCase in UV-2 and 5'FDU-1 strongly proves the functional consequences of gene mutation to lipid production. In conclusion, algal mutants exhibited significant impact on biodiesel production through structural alterations in the lipid-metabolizing genes, thereby enhancing lipid production and saturated fatty acid levels.

  11. Indole-3-acetic acid (IAA) induced changes in oil content, fatty acid profiles and expression of four fatty acid biosynthetic genes in Chlorella vulgaris at early stationary growth phase.

    PubMed

    Jusoh, Malinna; Loh, Saw Hong; Chuah, Tse Seng; Aziz, Ahmad; Cha, Thye San

    2015-03-01

    Microalgae lipids and oils are potential candidates for renewable biodiesel. Many microalgae species accumulate a substantial amount of lipids and oils under environmental stresses. However, low growth rate under these adverse conditions account for the decrease in overall biomass productivity which directly influence the oil yield. This study was undertaken to investigate the effect of exogenously added auxin (indole-3-acetic acid; IAA) on the oil content, fatty acid compositions, and the expression of fatty acid biosynthetic genes in Chlorella vulgaris (UMT-M1). Auxin has been shown to regulate growth and metabolite production of several microalgae. Results showed that oil accumulation was highest on days after treatment (DAT)-2 with enriched levels of palmitic (C16:0) and stearic (C18:0) acids, while the linoleic (C18:2) and α-linolenic (C18:3n3) acids levels were markedly reduced by IAA. The elevated levels of saturated fatty acids (C16:0 and C18:0) were consistent with high expression of the β-ketoacyl ACP synthase I (KAS I) gene, while low expression of omega-6 fatty acid desaturase (ω-6 FAD) gene was consistent with low production of C18:2. However, the increment of stearoyl-ACP desaturase (SAD) gene expression upon IAA induction did not coincide with oleic acid (C18:1) production. The expression of omega-3 fatty acid desaturase (ω-3 FAD) gene showed a positive correlation with the synthesis of PUFA and C18:3n3.

  12. Comparison of Chlorella vulgaris biomass productivity cultivated in biofilm and suspension from the aspect of light transmission and microalgae affinity to carbon dioxide.

    PubMed

    Huang, Yun; Xiong, Wei; Liao, Qiang; Fu, Qian; Xia, Ao; Zhu, Xun; Sun, Yahui

    2016-12-01

    To investigate light transmission and cells affinity to CO2, Chlorellavulgaris was attached to microfiltration membrane that laid on the solidified BG11 medium compared to that in suspended cultivation mode in this study. The results showed that C. vulgaris showed a 30.4% higher biomass production (103gm(-2)) in attached than in suspend system. The upper layer of biofilm with a thickness of 41.31μm (the corresponding areal density of 40gm(-2)) was effectively illuminated under light intensity of 120μmolm(-2)s(-1) and more than 40% of the microalgal cells were in light even the areal density was high to 100gm(-2). While only 2.5% of the cells were effectively illuminated in the suspended cultivation system. Furthermore, microalgae cells in biofilm showed a higher affinity to CO2 compared with that in suspension, and CO2 saturation point of microalgae cells in biofilm was 1.5% but 4.5% in suspension.

  13. Germination behavior, biochemical features and sequence analysis of the RACK1/arcA homolog from Phaseolus vulgaris

    PubMed Central

    Islas-Flores, Tania; Guillén, Gabriel; Islas-Flores, Ignacio; Román-Roque, Carolina San; Sánchez, Federico; Loza-Tavera, Herminia; Bearer, Elaine L.; Villanueva, Marco A.

    2010-01-01

    Partial peptide sequence of a 36 kDa protein from common bean embryo axes showed 100% identity with a reported β-subunit of a heterotrimeric G protein from soybean. Analysis of the full sequence showed 96.6% identity with the reported soybean Gβ -subunit, 86% with RACK1B and C from Arabidopsis and 66% with human and mouse RACK1, at the amino acid level. In addition, it showed 85.5, 85 and 83% identities with arcA from Solanum lycopersicum, Arabidopsis (RACK1A) and Nicotiana tabacum, respectively. The amino acid sequence displayed seven WD40 domains and two sites for activated protein kinase C binding. The protein showed a constant expression level but the mRNA had a maximum at 32 h post-imbibition. Western immunoblotting showed the protein in vegetative plant tissues, and in both microsomal and soluble fractions from embryo axes. Synthetic auxin treatment during germination delayed the peak of RACK1 mRNA expression to 48 h but did not affect the protein expression level while the polar auxin transport inhibitor, naphtylphtalamic acid had no effect on either mRNA or protein expression levels. Southern blot and genomic DNA amplification revealed a small gene family with at least one member without introns in the genome. Thus, the RACK1/arcA homolog from common bean has the following features: (1) it is highly conserved; (2) it is both soluble and insoluble within the embryo axis; (3) it is encoded by a small gene family; (4) its mRNA has a peak of expression at the time point of germination stop and (5) its expression is only slightly affected by auxin but unaffected by an auxin transport blocker. PMID:19832940

  14. Screening high oleaginous Chlorella strains from different climate zones.

    PubMed

    Xu, Jin; Hu, Hanhua

    2013-09-01

    In outdoor cultivation, screening strains adapted to a wide temperature range or suitable strains for different environmental temperatures is of great importance. In this study, triacylglycerol (TAG) content of 23 oil-producing Chlorella strains from different climate zones were analyzed by thin layer chromatography. Four selected Chlorella strains (NJ-18, NJ-7, NMX35N and NMX139N) with rather high TAG content had higher total lipid content compared with Chlorella vulgaris SAG 211-11b. In particular, NJ-18 displayed the highest TAG productivity among the four high oil-producing Chlorella strains. Accumulation of TAGs in strain NMX35N changed a little from 30 to 40°C, showing a desirable characteristic of accumulating TAGs at high temperatures. Our results demonstrated that NJ-18 and NMX35N had suitable fatty acid profiles and good adaption to low and high temperatures respectively. Therefore, cultivation of the two Chlorella strains together might be a good option for economic biodiesel production during the whole seasons of the year.

  15. Pemphigus vulgaris

    MedlinePlus

    ... this page: //medlineplus.gov/ency/article/000882.htm Pemphigus vulgaris To use the sharing features on this page, please enable JavaScript. Pemphigus vulgaris (PV) is an autoimmune disorder of the ...

  16. Ecological role of algobacterial cenosis links (chlorella - associated microflora or associated bacteria)

    NASA Astrophysics Data System (ADS)

    Pechurkin, N. S.

    The problems of interrelation of microalgae and bacteria in the "autotroph - heterotroph" aquatic biotic cycle are discussed. The cause and mechanisms of algobacterial cenosis formation still have been explained contradictorily. This work views the results of experimental and theoretical study of algobacterial cenosis functioning by the example of microalga Chlorella vulgaris and associated microflora. The representatives of Pseudomonas mainly predominate in the Chlorella microbial complex. The experiment at non-sterile batch cultivation of Chlorella on Tamya medium showed that the biomass of microorganisms increases simultaneously with the increase of microalgal biomass. Microflora of Chlorella can use organic materials evolved by Chlorella after photosynthesis for reproduction. Moreover, microorganisms can use dying cells of Chlorella, i.e. form the "producer - reducer" biocycle. To understand the cenosis-forming role of microalgae the mathematical model of the "autotroph - heterotroph" aquatic biotic cycle was constructed taking into consideration the opportunities for microorganisms of using Chlorella photosynthates, dying cells and contribution of links to the nitrogen cycle. The theoretical investigation showed that the biomass of associated bacteria growing on glucose and detritus exceeds the biomass of bacteria using only microalgal photosynthates, which is comparable with experimental data.

  17. Increase in Chlorella strains calorific values when grown in low nitrogen medium.

    PubMed

    Illman; Scragg; Shales

    2000-11-01

    The calorific value of five strains of Chlorella grown in Watanabe and low-nitrogen medium was determined. The algae were grown in small (2L) stirred tank bioreactors and the best growth was obtained with Chlorella vulgaris with a growth rate of 0.99 d(-1) and the highest calorific value (29 KJ/g) was obtained with C. emersonii. The cellular components were assayed at the end of the growth period and the calorific value appears to be linked to the lipid content rather than any other component.

  18. Widespread green algae Chlorella and Stichococcus exhibit polar-temperate and tropical-temperate biogeography.

    PubMed

    Hodač, Ladislav; Hallmann, Christine; Spitzer, Karolin; Elster, Josef; Faßhauer, Fabian; Brinkmann, Nicole; Lepka, Daniela; Diwan, Vaibhav; Friedl, Thomas

    2016-08-01

    Chlorella and Stichococcus are morphologically simple airborne microalgae, omnipresent in terrestrial and aquatic habitats. The minute cell size and resistance against environmental stress facilitate their long-distance dispersal. However, the actual distribution of Chlorella- and Stichococcus-like species has so far been inferred only from ambiguous morphology-based evidence. Here we contribute a phylogenetic analysis of an expanded SSU and ITS2 rDNA sequence dataset representing Chlorella- and Stichococcus-like species from terrestrial habitats of polar, temperate and tropical regions. We aim to uncover biogeographical patterns at low taxonomic levels. We found that psychrotolerant strains of Chlorella and Stichococcus are closely related with strains originating from the temperate zone. Species closely related to Chlorella vulgaris and Muriella terrestris, and recovered from extreme terrestrial environments of polar regions and hot deserts, are particularly widespread. Stichococcus strains from the temperate zone, with their closest relatives in the tropics, differ from strains with the closest relatives being from the polar regions. Our data suggest that terrestrial Chlorella and Stichococcus might be capable of intercontinental dispersal; however, their actual distributions exhibit biogeographical patterns.

  19. Comparative toxicity and structure-activity in Chlorella and Tetrahymena: Monosubstituted phenols

    SciTech Connect

    Jaworska, J.S.; Schultz, T.W. )

    1991-07-01

    The relative toxicity of selected monosubstituted phenols has been assessed by Kramer and Truemper in the Chlorella vulgaris assay. The authors examined population growth inhibition of this simple green algae under short-term static conditions for 33 derivatives. However, efforts to develop a strong predictive quantitative structure-activity relationship (QSAR) met with limited success because they modeled across modes of toxic action or segregated derivatives such as positional isomers (i.e., ortho-, meta-, para-). In an effort to further their understanding of the relationships of ecotoxic effects of phenols, the authors have evaluated the same derivatives reported by Kramer and Truemper in the Tetrahymena pyriformis population growth assay, compared the responses in both systems and developed QSARs for the Chlorella vulgaris data based on mechanisms of action.

  20. Water Permeability of Chlorella Cell Membranes by Nuclear Magnetic Resonance

    PubMed Central

    Stout, Darryl G.; Steponkus, Peter L.; Bustard, Larry D.; Cotts, Robert M.

    1978-01-01

    Measurement by two nuclear magnetic resonance (NMR) techniques of the mean residence time τa of water molecules inside Chlorella vulgaris (Beijerinck) var. “viridis” (Chodot) is reported. The first is the Conlon and Outhred (1972 Biochim Biophys Acta 288: 354-361) technique in which extracellular water is doped with paramagnetic Mn2+ ions. Some complications in application of this technique are identified as being caused by the affinity of Chlorella cell walls for Mn2+ ions which shortens the NMR relaxation times of intra- and extracellular water. The second is based upon observations of effects of diffusion on the spin echo of intra- and extracellular water. Echo attenuation of intracellular water is distinguished from that of extracellular water by the extent to which diffusive motion is restricted. Intracellular water, being restricted to the cell volume, suffers less echo attenuation. From the dependence of echo amplitude upon gradient strength at several values of echo time, the mean residence time of intracellular water can be determined. From the mean residence time of intracellular water, the diffusional water permeability coefficient of the Chlorella membrane is calculated to be 2.1 ± 0.4 × 10−3 cm sec−1. PMID:16660456

  1. Population of Vibrational State of Carotenoid Molecules in Living Cells of Chlorella

    NASA Astrophysics Data System (ADS)

    Kinoshita, Shuichi; Hirata, Kuniko; Kushida, Takashi

    1980-07-01

    Stokes and anti-Stokes Raman spectra have been measured in living cells of Chlorella vulgaris as well as in chloroform, toluene, benzene and β-carotene. Population in the vibrational state has been determined by taking account of resonance Raman effect. The result shows that this population is well explained by thermal distribution even in the case of living biological cells, contrary to recently reported observation of some population enhancement. Possible experimental artifacts are discussed.

  2. Detoxification of chlorella supplement on heterocyclic amines in Korean young adults.

    PubMed

    Lee, Inyeong; Tran, Minhphuong; Evans-Nguyen, Theresa; Stickle, Dawn; Kim, Soyeon; Han, Jaegab; Park, Jong Y; Yang, Mihi

    2015-01-01

    Heterocyclic amines (HCAs) and polycyclic aromatic hydrocarbons (PAHs) have been established as carcinogenic chemicals in Western diet. This study was performed to estimate HCA exposure levels in Korean daily life and to assess the ability of Chlorella vulgaris to detoxify carcinogenic HCAs in a randomized, double blind, placebo-controlled crossover study with chlorella supplement (N=6, all females, age: 27.17±7.73yr) for 2 weeks. We analyzed HCAs in hydrolyzed urine specimens using LC/TOF-MS. As results, urinary levels of MeIQx, PhIP, and IQx-8-COOH were 323.36±220.11ng/L, 351.59±254.93ng/L, and 130.85±83.22ng/L, respectively. Effects of chlorella to reduce urinary MeIQx were marginally significant (before, 430±226.86pg/mL vs. after, 174.45±101.65pg/mL: 0.05chlorella supplementation. In conclusion, our study demonstrates that current daily levels of HCA exposure in Korean young adults are not lower than those in the Western world. In addition, the effects of chlorella's to detoxify HCAs likely occur by interfering e with absorption or metabolism.

  3. Inhibition of lipase and inflammatory mediators by Chlorella lipid extracts for antiacne treatment

    PubMed Central

    Sibi, G.

    2015-01-01

    Acne vulgaris is a chronic inflammatory disease, and its treatment is challenging due to the multifactorial etiology and emergence of antibiotic-resistant Propionibacterium acnes strains. This study was focused to reduce antibiotics usage and find an alternate therapeutic source for treating acne. Lipid extracts of six Chlorella species were tested for inhibition of lipase, reactive oxygen species (ROS) production, cytokine production using P. acnes (Microbial Type Culture Collection 1951). Lipase inhibitory assay was determined by dimercaprol Tributyrate - 5, 5'- dithiobis 2-nitrobenzoic acid method and ROS production assay was performed using nitro-blue tetrazolium test. The anti-inflammatory activity of algal lipid extracts was determined by in vitro screening method based on inhibition of pro-inflammatory cytokines, tumor necrosis factor-alpha (TNF-α) produced by human peripheral blood mononuclear cells. Minimum inhibitory concentration (MIC) values of lipid extracts were determined by microdilution method, and the fatty acid methyl esters (FAME) were analyzed by gas chromatography-mass spectroscopy. Chlorella ellipsoidea has the highest lipase inhibitory activity with 61.73% inhibition, followed by Chlorella vulgaris (60.31%) and Chlorella protothecoides (58.9%). Lipid extracts from C. protothecoides and C. ellipsoidea has significantly reduced the ROS production by 61.27% and 58.34% respectively. Inhibition of pro-inflammatory cytokines TNF-α showed the inhibition ranging from 58.39% to 78.67%. C. vulgaris has exhibited the MICvalue of 10 μg/ml followed by C. ellipsoidea, C. protothecoides and Chlorella pyrenoidosa (20 μg/ml). FAME analysis detected 19 fatty acids of which 5 were saturated fatty acids, and 14 were unsaturated fatty acids ranging from C14 to C24. The results suggest that lipid extracts of Chlorella species has significant inhibitory activity on P. acnes by inhibiting lipase activity. Further, anti-inflammatory reaction caused by the

  4. Cultivation Of Microalgae (Chlorella vulgaris) For Biodiesel Production

    NASA Astrophysics Data System (ADS)

    Blinová, Lenka; Bartošová, Alica; Gerulová, Kristína

    2015-06-01

    Production of biofuel from renewable sources is considered to be one of the most sustainable alternatives to petroleum sourced fuels. Biofuels are also viable means of environmental and economic sustainability. Biofuels are divided into four generations, depending on the type of biomass used for biofuels production. At present, microalgae are presented as an ideal third generation biofuel feedstock because of their rapid growth rate. They also do not compete with food or feed crops, and can be produced on non-arable land. Cultivation conditions (temperature, pH, light, nutrient quantity and quality, salinity, aerating) are the major factors that influence photosynthesis activity and behaviour of the microalgae growth rate. In this paper, we present an overview about the effect of cultivation conditions on microalgae growth.

  5. Enhanced accumulation of starch and total carbohydrates in alginate-immobilized Chlorella spp. induced by Azospirillum brasilense: II. Heterotrophic conditions.

    PubMed

    Choix, Francisco J; de-Bashan, Luz E; Bashan, Yoav

    2012-10-10

    The effect of the bacterium Azospirillum brasilense jointly immobilized with Chlorella vulgaris or C. sorokiniana in alginate beads on total carbohydrates and starch was studied under dark and heterotrophic conditions for 144 h in synthetic growth medium supplemented with either d-glucose or Na-acetate as carbon sources. In all treatments, enhanced total carbohydrates and starch content per culture and per cell was obtained after 24h; only jointly immobilized C. vulgaris growing on d-glucose significantly increased total carbohydrates and starch content after 96 h. Enhanced accumulation of carbohydrate and starch under jointly immobilized conditions was variable with time of sampling and substrate used. Similar results occurred when the microalgae was immobilized alone. In both microalgae growing on either carbon sources, the bacterium promoted accumulation of carbohydrates and starch; when the microalgae were immobilized alone, they used the carbon sources for cell multiplication. In jointly immobilized conditions with Chlorella spp., affinity to carbon source and volumetric productivity and yield were higher than when Chlorella spp. were immobilized alone; however, the growth rate was higher in microalgae immobilized alone. This study demonstrates that under heterotrophic conditions, A. brasilense promotes the accumulation of carbohydrates in two strains Chlorella spp. under certain time-substrate combinations, producing mainly starch. As such, this bacterium is a biological factor that can change the composition of compounds in microalgae in dark, heterotrophic conditions.

  6. Acne vulgaris.

    PubMed

    Robertson, Kevin M

    2004-08-01

    Acne vulgaris is a common inflammatory skin condition that presents management difficulties to cosmetic surgeons. Acute management and treatment focuses on early diagnosis as well as treatment with topical agents, oral antibiotics, hormonal therapy,and nonablative chemical peel and laser applications. The treatment of postinflammatory scarring must be individualized to address potential macular dyschromia, cystic lesions,epithelial bridges, or deep pitted scars. A review of interventional options is presented to apply to the spectrum of acne scarring as well as a review of the literature to address objectively published reports on efficacy.

  7. Interactive Effects of Temperature and UV Radiation on Photosynthesis of Chlorella Strains from Polar, Temperate and Tropical Environments: Differential Impacts on Damage and Repair

    PubMed Central

    Wong, Chiew-Yen; Teoh, Ming-Li; Phang, Siew-Moi; Lim, Phaik-Eem; Beardall, John

    2015-01-01

    Global warming and ozone depletion, and the resulting increase of ultraviolet radiation (UVR), have far-reaching impacts on biota, especially affecting the algae that form the basis of the food webs in aquatic ecosystems. The aim of the present study was to investigate the interactive effects of temperature and UVR by comparing the photosynthetic responses of similar taxa of Chlorella from Antarctic (Chlorella UMACC 237), temperate (Chlorella vulgaris UMACC 248) and tropical (Chlorella vulgaris UMACC 001) environments. The cultures were exposed to three different treatments: photosynthetically active radiation (PAR; 400–700 nm), PAR plus ultraviolet-A (320–400 nm) radiation (PAR + UV-A) and PAR plus UV-A and ultraviolet-B (280–320 nm) radiation (PAR + UV-A + UV-B) for one hour in incubators set at different temperatures. The Antarctic Chlorella was exposed to 4, 14 and 20°C. The temperate Chlorella was exposed to 11, 18 and 25°C while the tropical Chlorella was exposed to 24, 28 and 30°C. A pulse-amplitude modulated (PAM) fluorometer was used to assess the photosynthetic response of microalgae. Parameters such as the photoadaptive index (Ek) and light harvesting efficiency (α) were determined from rapid light curves. The damage (k) and repair (r) rates were calculated from the decrease in ΦPSIIeff over time during exposure response curves where cells were exposed to the various combinations of PAR and UVR, and fitting the data to the Kok model. The results showed that UV-A caused much lower inhibition than UV-B in photosynthesis in all Chlorella isolates. The three isolates of Chlorella from different regions showed different trends in their photosynthesis responses under the combined effects of UVR (PAR + UV-A + UV-B) and temperature. In accordance with the noted strain-specific characteristics, we can conclude that the repair (r) mechanisms at higher temperatures were not sufficient to overcome damage caused by UVR in the Antarctic Chlorella strain

  8. Interactive Effects of Temperature and UV Radiation on Photosynthesis of Chlorella Strains from Polar, Temperate and Tropical Environments: Differential Impacts on Damage and Repair.

    PubMed

    Wong, Chiew-Yen; Teoh, Ming-Li; Phang, Siew-Moi; Lim, Phaik-Eem; Beardall, John

    2015-01-01

    Global warming and ozone depletion, and the resulting increase of ultraviolet radiation (UVR), have far-reaching impacts on biota, especially affecting the algae that form the basis of the food webs in aquatic ecosystems. The aim of the present study was to investigate the interactive effects of temperature and UVR by comparing the photosynthetic responses of similar taxa of Chlorella from Antarctic (Chlorella UMACC 237), temperate (Chlorella vulgaris UMACC 248) and tropical (Chlorella vulgaris UMACC 001) environments. The cultures were exposed to three different treatments: photosynthetically active radiation (PAR; 400-700 nm), PAR plus ultraviolet-A (320-400 nm) radiation (PAR + UV-A) and PAR plus UV-A and ultraviolet-B (280-320 nm) radiation (PAR + UV-A + UV-B) for one hour in incubators set at different temperatures. The Antarctic Chlorella was exposed to 4, 14 and 20°C. The temperate Chlorella was exposed to 11, 18 and 25°C while the tropical Chlorella was exposed to 24, 28 and 30°C. A pulse-amplitude modulated (PAM) fluorometer was used to assess the photosynthetic response of microalgae. Parameters such as the photoadaptive index (Ek) and light harvesting efficiency (α) were determined from rapid light curves. The damage (k) and repair (r) rates were calculated from the decrease in ΦPSIIeff over time during exposure response curves where cells were exposed to the various combinations of PAR and UVR, and fitting the data to the Kok model. The results showed that UV-A caused much lower inhibition than UV-B in photosynthesis in all Chlorella isolates. The three isolates of Chlorella from different regions showed different trends in their photosynthesis responses under the combined effects of UVR (PAR + UV-A + UV-B) and temperature. In accordance with the noted strain-specific characteristics, we can conclude that the repair (r) mechanisms at higher temperatures were not sufficient to overcome damage caused by UVR in the Antarctic Chlorella strain

  9. Enhanced accumulation of starch and total carbohydrates in alginate-immobilized Chlorella spp. induced by Azospirillum brasilense: I. Autotrophic conditions.

    PubMed

    Choix, Francisco J; de-Bashan, Luz E; Bashan, Yoav

    2012-10-10

    The effect of the microalgae-growth promoting bacterium Azospirillum brasilense on accumulation of total carbohydrates and starch in two species of Chlorella (Chlorella vulgaris and Chlorella sorokiniana), when the bacterium and each microalga were jointly immobilized in alginate beads was studied under autotrophic conditions for 144 h in synthetic medium. The interaction of the bacterium with the microalgae enhanced accumulation of total carbohydrate and starch. Cells of Chlorella accumulated the highest amounts of carbohydrate after incubation for 24h. Yet, this did not coincide with the highest affinity and volumetric productivity measured in these cultures. However, after incubation for 72 h, mainly in jointly immobilized treatments of both microalgae species, the cultures reached their highest total carbohydrate content (mainly as starch) and also the highest affinity and volumetric productivity. These results demonstrate the potential of A. brasilense to affect carbohydrates and starch accumulation in Chlorella spp. when both microorganisms are co-cultured, which can be an important tool for applications of microalgae.

  10. Chlorella: 125 years of the green survivalist.

    PubMed

    Krienitz, Lothar; Huss, Volker A R; Bock, Christina

    2015-02-01

    Chlorella, the archetype of unicellular green algae, is a high-performance primary producer in aquatic and terrestrial ecosystems. Under the simple spherical morphology of Chlorella, many other 'green balls' unfolded as independent phylogenetic lineages as a result of convergent evolution. By contrast, green algae with strikingly different phenotypes were unmasked as close relatives of Chlorella by modern molecular techniques. Here, we point to the increasing impact of these diverse protists on ecology, evolution, and biotechnology in the light of integrative taxonomy.

  11. Chlorella viruses isolated in China

    SciTech Connect

    Zhang, Y.; Burbank, D.E.; Van Etten, J.L. )

    1988-09-01

    Plaque-forming viruses of the unicellular, eukaryotic, exsymbiotic, Chlorella-like green algae strain NC64A, which are common in the United States, were also present in fresh water collected in the People's Republic of China. Seven of the Chinese viruses were examined in detail and compared with the Chlorella viruses previously isolated in the United States. Like the American viruses, the Chinese viruses were large polyhedra and sensitive to chloroform. They contained numerous structural proteins and large double-stranded DNA genomes of at least 300 kilobase pairs. Each of the DNAs from the Chinese viruses contained 5-methyldeoxycytosine, which varied from 12.6 to 46.7% of the deoxycytosine, and N{sup 6}-methyldeoxyadenosine, which varied from 2.2 to 28.3% of the deoxyadenosine. Four of the Chinese virus DNAs hybridized extensively with {sup 32}P-labeled DNA from the American virus PBCV-1, and three hybridized poorly.

  12. Acne vulgaris.

    PubMed

    Wilson, B B

    1989-09-01

    Acne vulgaris is a disease of the pilosebaceous unit that affects nearly all persons to some degree during the teenage years. It is a disease that should be treated because of the anxiety and disfigurement it causes in the affected patient. Acne therapy is directed against the three probable pathogenic processes in acne: (1) abnormal keratinization of the sebaceous follicle, (2) excessive production of sebum, and (3) proliferation of bacteria in the follicle. Superficial acne consisting of comedones and small papulopustules will frequently respond to topical therapy such as retinoic acid, benzoyl peroxide, and topical antibiotics. Deeper lesions require systemic antibiotics of which tetracycline is the drug of choice. Severe, recalcitrant cystic acne usually responds well to the oral retinoid, isotretinoin. The severe teratogenic effects of isotretinoin on a developing fetus make this a risky drug to prescribe for women with childbearing potential. In such cases the greatest precautions should be taken to avoid pregnancy during a course of isotretinoin. Such precautions include pregnancy testing, contraceptive counseling, and the use of at least two effective forms of birth control in sexually active women.

  13. Starch and lipid accumulation in eight strains of six Chlorella species under comparatively high light intensity and aeration culture conditions.

    PubMed

    Takeshita, Tsuyoshi; Ota, Shuhei; Yamazaki, Tomokazu; Hirata, Aiko; Zachleder, Vilém; Kawano, Shigeyuki

    2014-04-01

    The microalgae family Chlorella species are known to accumulate starch and lipids. Although nitrogen or phosphorous deficiencies promote starch and lipids formation in many microalgae, these deficiencies also limit their growth and productivity. Therefore, the Chlorellaceae strains were attempted to increase starch and lipids productivity under high-light-intensity conditions (600-μmol photons m(-2)s(-1)). The 12:12-h light-dark (LD) cycle conditions elicited more stable growth than the continuous light (LL) conditions, whereas the starch and lipids yields increased in LL conditions. The amount of starch and lipids per cell increased in Chlorella viscosa and Chlorella vulgaris in sulfur-deficient medium, and long-chain fatty acids with 20 or more carbon atoms accumulated in cells grown in sulfur-deficient medium. Accumulation of starch and lipids was investigated in eight strains. The accumulation was strain-dependent, and varied according to the medium and light conditions. Five of the eight Chlorella strains exhibited similar accumulation patterns.

  14. Biology and Industrial Applications of Chlorella: Advances and Prospects.

    PubMed

    Liu, Jin; Chen, Feng

    2016-01-01

    Chlorella represents a group of eukaryotic green microalgae that has been receiving increasing scientific and commercial interest. It possesses high photosynthetic ability and is capable of growing robustly under mixotrophic and heterotrophic conditions as well. Chlorella has long been considered as a source of protein and is now industrially produced for human food and animal feed. Chlorella is also rich in oil, an ideal feedstock for biofuels. The exploration of biofuel production by Chlorella is underway. Chlorella has the ability to fix carbon dioxide efficiently and to remove nutrients of nitrogen and phosphorous, making it a good candidate for greenhouse gas biomitigation and wastewater bioremediation. In addition, Chlorella shows potential as an alternative expression host for recombinant protein production, though challenges remain to be addressed. Currently, omics analyses of certain Chlorella strains are being performed, which will help to unravel the biological implications of Chlorella and facilitate the future exploration of industrial applications.

  15. The development of photosynthesis in a greening mutant of chlorella and an analysis of the light saturation curve.

    PubMed

    Herron, H A; Mauzerall, D

    1972-07-01

    Photosynthetic oxygen evolution considerably precedes the rise in chlorophyll during the greening of a yellow mutant of Chlorella vulgaris. Dark-grown cells required 20 times more light to saturate photosynthesis than light-grown or normal cells. The chlorophyll appears to add first to active reaction centers, then to fill in a more general antenna. The carotenoid pigments seem to add more randomly to the reaction centers. The shape of the light saturation curves can be explained with the assumption that an excitation in the antenna can reach several reaction centers. The efficiency of the total unit is constant during the greening process.

  16. Cathodic arcs

    SciTech Connect

    Anders, Andre

    2003-10-29

    Cathodic arc plasma deposition has become the technology of choice for hard, wear and corrosion resistant coatings for a variety of applications. The history, basic physics of cathodic arc operation, the infamous macroparticle problem and common filter solutions, and emerging high-tech applications are briefly reviewed. Cathodic arc plasmas standout due to their high degree of ionization, with important consequences for film nucleation, growth, and efficient utilization of substrate bias. Industrial processes often use cathodic arc plasma in reactive mode. In contrast, the science of arcs has focused on the case of vacuum arcs. Future research directions include closing the knowledge gap for reactive mode, large area coating, linear sources and filters, metal plasma immersion process, with application in high-tech and biomedical fields.

  17. Combining and Comparing Coalescent, Distance and Character-Based Approaches for Barcoding Microalgaes: A Test with Chlorella-Like Species (Chlorophyta).

    PubMed

    Zou, Shanmei; Fei, Cong; Song, Jiameng; Bao, Yachao; He, Meilin; Wang, Changhai

    2016-01-01

    Several different barcoding methods of distinguishing species have been advanced, but which method is the best is still controversial. Chlorella is becoming particularly promising in the development of second-generation biofuels. However, the taxonomy of Chlorella-like organisms is easily confused. Here we report a comprehensive barcoding analysis of Chlorella-like species from Chlorella, Chloroidium, Dictyosphaerium and Actinastrum based on rbcL, ITS, tufA and 16S sequences to test the efficiency of traditional barcoding, GMYC, ABGD, PTP, P ID and character-based barcoding methods. First of all, the barcoding results gave new insights into the taxonomic assessment of Chlorella-like organisms studied, including the clear species discrimination and resolution of potentially cryptic species complexes in C. sorokiniana, D. ehrenbergianum and C. Vulgaris. The tufA proved to be the most efficient barcoding locus, which thus could be as potential "specific barcode" for Chlorella-like species. The 16S failed in discriminating most closely related species. The resolution of GMYC, PTP, P ID, ABGD and character-based barcoding methods were variable among rbcL, ITS and tufA genes. The best resolution for species differentiation appeared in tufA analysis where GMYC, PTP, ABGD and character-based approaches produced consistent groups while the PTP method over-split the taxa. The character analysis of rbcL, ITS and tufA sequences could clearly distinguish all taxonomic groups respectively, including the potentially cryptic lineages, with many character attributes. Thus, the character-based barcoding provides an attractive complement to coalescent and distance-based barcoding. Our study represents the test that proves the efficiency of multiple DNA barcoding in species discrimination of microalgaes.

  18. Reclamation of wastewater for polyculture of freshwater fish: bioassays using Chlorella and Gambusia.

    PubMed

    Liang, Y; Wong, M H

    2000-11-01

    The feasibility of using the secondary effluents from two sewage treatment plants in Hong Kong (Yuen Long and Shek Wu Hui) for fish culture was assessed. Total ammonia contents in the two sewage effluents surpassed the level of 2 mg L(-1) recommended for wastewater fish culture. The two sewage effluents both needed essential elements for supporting algal Chlorella vulgaris growth, whereas only sewage effluent from Yuen Long had contaminants at toxic levels. Total ammonia in water explained more than 80% variations of toxicity of water samples to Gambusia patruelis, mosquito fish, according to regression analysis. Removal of ammonia from the sewage effluent is necessary before being used for fish culture. In addition, the rather high levels of heavy metals (Cu, Zn, Cd) in the effluent should be closely monitored.

  19. CLONING AND EXPRESSING TRYPSIN MODULATING OOSTATIC FACTOR IN Chlorella desiccata TO CONTROL MOSQUITO LARVAE.

    PubMed

    Borovsky, Dov; Sterner, Andeas; Powell, Charles A

    2016-01-01

    The insect peptide hormone trypsin modulating oostatic factor (TMOF), a decapeptide that is synthesized by the mosquito ovary and controls the translation of the gut's trypsin mRNA was cloned and expressed in the marine alga Chlorella desiccata. To express Aedes aegypti TMOF gene (tmfA) in C. desiccata cells, two plasmids (pYES2/TMOF and pYDB4-tmfA) were engineered with pKYLX71 DNA (5 Kb) carrying the cauliflower mosaic virus (CaMV) promoter 35S(2) and the kanamycin resistant gene (neo), as well as, a 8 Kb nitrate reductase gene (nit) from Chlorella vulgaris. Transforming C. desiccata with pYES2/TMOF and pYDB4-tmfA show that the engineered algal cells express TMOF (20 ± 4 μg ± SEM and 17 ± 3 μg ± SEM, respectively in 3 × 10(8) cells) and feeding the cells to mosquito larvae kill 75 and 60% of Ae. aegypti larvae in 4 days, respectively. Southern and Northern blots analyses show that tmfA integrated into the genome of C. desiccata by homologous recombination using the yeast 2 μ circle of replication and the nit in pYES2/TMOF and pYDB4-tmfA, respectively, and the transformed algal cells express tmfA transcript. Using these algal cells it will be possible in the future to control mosquito larvae in the marsh.

  20. Mixotrophic cultivation of Chlorella for local protein production using agro-food by-products.

    PubMed

    Salati, Silvia; D'Imporzano, Giuliana; Menin, Barbara; Veronesi, Davide; Scaglia, Barbara; Abbruscato, Pamela; Mariani, Paola; Adani, Fabrizio

    2017-04-01

    A local strain of Chlorella vulgaris was cultivated by using cheese whey (CW), white wine lees (WL) and glycerol (Gly), coming from local agro-industrial activities, as C sources (2.2gCL(-1)) to support algae production under mixotrophic conditions in Lombardy. In continuous mode, Chlorella increased biomass production compared with autotrophic conditions by 1.5-2 times, with the best results obtained for the CW substrate, i.e. 0.52gL(-1)d(-1) of algal biomass vs. 0.24gL(-1)d(-1) of algal biomass for autotrophic conditions, and protein content for both conditions adopted close to 500gkg(-1) DM. Mixotrophic conditions gave a much higher energy recovery efficiency (EF) than autotrophic conditions, i.e. organic carbon energy efficiency (EFoc) of 32% and total energy efficiency (Eft) of 8%, respectively, suggesting the potential for the culture of algae as a sustainable practice to recover efficiently waste-C and a means of local protein production.

  1. Substitution of stable isotopes in Chlorella

    NASA Technical Reports Server (NTRS)

    Flaumenhaft, E.; Katz, J. J.; Uphaus, R. A.

    1969-01-01

    Replacement of biologically important isotopes in the alga Chlorella by corresponding heavier stable isotopes produces increasingly greater deviations from the normal cell size and changes the quality and distribution of certain cellular components. The usefulness of isotopically altered organisms increases interest in the study of such permuted organisms.

  2. Lupus vulgaris of external nose.

    PubMed

    Bhandary, Satheesh Kumar; Ranganna, B Usha

    2008-12-01

    Lupus vulgaris is the commonest form of cutaneous tuberculosis which commonly involve trunk and buttocks. Lupus vulgaris affecting nose and face, are rarely reported in India. This study reports an unusual case of lupus vulgaris involving the external nose that showed dramatic outcome after six months of anti- tubercular treatment.

  3. Lupus vulgaris: difficulties in diagnosis.

    PubMed

    Rhodes, Julia; Caccetta, Tony Philip; Tait, Clare

    2013-05-01

    Lupus vulgaris is one of the most common forms of cutaneous tuberculosis. It presents a diagnostic challenge due to its paucibacillary nature. This is a report of a case of a delayed diagnosis of lupus vulgaris, presenting as perianal and peristomal plaques, followed by a review of the diagnostic tools for lupus vulgaris and their limitations.

  4. Elements of arc welding

    SciTech Connect

    Not Available

    1993-07-01

    This paper looks at the following arc welding techniques: (1) shielded metal-arc welding; (2) submerged-arc welding; (3) gas metal-arc welding; (4) flux-cored arc welding; (5) electrogas welding; (6) gas tungsten-arc welding; and (7) plasma-arc welding.

  5. Psoriasiform lupus vulgaris.

    PubMed

    Padmavathy, L; Rao, L Lakshmana; Ethirajan, N; Dhanlaklshmi, M

    2008-04-01

    Tuberculosis is a major public health problem in both developing and developed countries. Cutaneous Tuberculosis constitutes a minor proportion of extra-pulmonary manifestations of Tuberculosis. Lupus Vulgaris (LV) is one of the clinical variants of Cutaneous Tuberculosis. A case of a large plaque type psoriasiform lesion of lupus vulgaris on the thigh, of 15 years' duration, in an 18-year-old girl is reported. This case highlights the ignorance level among the patients and consequent failure to avail proper anti-tuberculous treatment despite campaign in print and audio visual media.

  6. Combining and Comparing Coalescent, Distance and Character-Based Approaches for Barcoding Microalgaes: A Test with Chlorella-Like Species (Chlorophyta)

    PubMed Central

    Zou, Shanmei; Fei, Cong; Song, Jiameng; Bao, Yachao; He, Meilin; Wang, Changhai

    2016-01-01

    Several different barcoding methods of distinguishing species have been advanced, but which method is the best is still controversial. Chlorella is becoming particularly promising in the development of second-generation biofuels. However, the taxonomy of Chlorella–like organisms is easily confused. Here we report a comprehensive barcoding analysis of Chlorella-like species from Chlorella, Chloroidium, Dictyosphaerium and Actinastrum based on rbcL, ITS, tufA and 16S sequences to test the efficiency of traditional barcoding, GMYC, ABGD, PTP, P ID and character-based barcoding methods. First of all, the barcoding results gave new insights into the taxonomic assessment of Chlorella-like organisms studied, including the clear species discrimination and resolution of potentially cryptic species complexes in C. sorokiniana, D. ehrenbergianum and C. Vulgaris. The tufA proved to be the most efficient barcoding locus, which thus could be as potential “specific barcode” for Chlorella-like species. The 16S failed in discriminating most closely related species. The resolution of GMYC, PTP, P ID, ABGD and character-based barcoding methods were variable among rbcL, ITS and tufA genes. The best resolution for species differentiation appeared in tufA analysis where GMYC, PTP, ABGD and character-based approaches produced consistent groups while the PTP method over-split the taxa. The character analysis of rbcL, ITS and tufA sequences could clearly distinguish all taxonomic groups respectively, including the potentially cryptic lineages, with many character attributes. Thus, the character-based barcoding provides an attractive complement to coalescent and distance-based barcoding. Our study represents the test that proves the efficiency of multiple DNA barcoding in species discrimination of microalgaes. PMID:27092945

  7. Inoculation lupus vulgaris.

    PubMed

    Sehgal, V N; Jain, S; Gupta, R

    1992-01-01

    An 11-years-old girl with lupus vulgaris on the right buttock following inoculation is described. The diagnosis was formed by the history, morphological characteristics, Mantoux test, histopathology, and was supported by an affirmative response to short course intensive chemotherapy (6 months). This route of infection acquires special significance with the worldwide-spread of HIV infection.

  8. Pemphigus vulgaris and disseminated nocardiosis.

    PubMed

    Martín, F J; Pérez-Bernal, A M; Camacho, F

    2000-09-01

    Infectious diseases, in particular septicaemia from Staphylococcus aureus, Proteus vulgaris and Pseudomonas aeruginosa, are the most severe and frequent complications for the immunosuppressive therapy of pemphigus. Infection by Nocardia asteroides in subjects with pemphigus vulgaris is rare. We report the sixth case found of such an association; the subject died of disseminated nocardiosis while receiving steroids and immunosuppressive drugs, 4 years after being diagnosed with chronic pemphigus vulgaris.

  9. Lung and lupus vulgaris.

    PubMed

    Mukta, V; Jayachandran, K

    2011-04-01

    Lupus vulgaris is chronic, postprimary, paucibacillary cutaneous tuberculosis found in individuals with moderate immunity and high degree of tuberculin sensitivity. Eighty percent of the lesions are on the head and neck. We present the case of a 38 year old lady who was admitted with complaints of worsening breathlessness and low grade fever of one month duration. Examination showed multiple, nontender skin ulcers on bilateral lumbar areas, two oozing serosanguinous discharge and others scarred in the centre. Respiratory system examination and chest X-ray revealed right sided pleural effusion. On investigation, pleural fluid was tuberculous in nature. Skin biopsy from the edge of ulcer was also suggestive of tuberculosis. Patient is doing well on antituberculous drugs. This case highlights the importance of cutaneous manifestations of systemic disease and is an example of the unusual presentation of lupus vulgaris in a case of pleural effusion.

  10. [Cefaclor induced pemphigus vulgaris].

    PubMed

    Scardina, G A; Conti, N M; Messina, P

    2004-01-01

    Pemphigus is a chronic disease with an outcome that is not without risk. It is characterised by loss of the intraepithelial cell-cell relationship (acantholysis). Underlying the disease is an autoimmune disorder in which the desmosomes are damaged by antibodies directed against particular molecules called desmogleins (particularly 3 and 1). Various types of pemphigus have been described with different antibody profiles and clinical signs. In the present paper, a case of pemphigus vulgaris associated with the medication cefaclor monohydrate is reported. Histological and immunological evaluation of the biopsy sample led to a diagnosis of pemphigus vulgaris. The patient, who was not hospitalised, was treated with corticosteroids and systemic immunosuppressors. At present she is being controlled by low doses of systemic corticosteroids. Early diagnosis and the timely introduction of the therapeutic protocol permitted complete remission of the lesions observed at the level of the oral and conjunctival mucosa, preventing the involvement of other locations.

  11. Pemphigus vulgaris in pregnancy.

    PubMed

    Salzberg, Kelsey W; Gero, Melanie J; Ragsdale, Bruce D

    2014-10-01

    We report the case of a 34-year-old woman who was diagnosed with pemphigus vulgaris (PV) during pregnancy. The patient presented with widespread blistering dermatitis and associated burning and pruritus. At 6 weeks' gestation the patient was admitted to the hospital to expedite her diagnosis and initiate treatment. A skin biopsy revealed suprabasal acantholysis, and direct immunofluorescence demonstrated diffuse intercellular IgG in the epidermis and basal intercellular C3, which confirmed the diagnosis of PV. Treatment with corticosteroids was instituted after discussions with the patient about possible adverse effects to the fetus. Pemphigus vulgaris is rare in pregnancy and active PV presents potential threats of fetal spread and transient lesion production, which is associated with increased mortality and morbidity in the fetus. Our patient had active PV and required treatment throughout her pregnancy. The pregnancy progressed to premature delivery of the neonate without skin lesions or apparent complications.

  12. Genotype versus phenotype variability in Chlorella and Micractinium (Chlorophyta, Trebouxiophyceae).

    PubMed

    Luo, Wei; Pflugmacher, Stephan; Pröschold, Thomas; Walz, Norbert; Krienitz, Lothar

    2006-08-01

    The most recent revision of the genus Chlorella, based on biochemical and SSU rDNA analyses, suggested a reduction to a set of four "true" spherical Chlorella species, while a growing number of morphologically different species such as Micractinium (formerly Micractiniaceae) were found to cluster within the clade of "true"Chlorella. In this study, the generic concept in Chlorellaceae to Chlorella and Micractinium was evaluated by means of combined SSU and ITS-2 rDNA sequence analyses and biotests to induce development of bristles on the cell wall. Molecular phylogenetic analyses of Chlorella and Micractinium strains confirmed their separation into two different genera. In addition, non-homoplasious synapomorphies (NHS) and compensatory base changes (CBC) in the secondary structures of SSU and ITS-2 rDNA sequences were found for both genera using this approach. The Micractinium clade can be differentiated into three different genotypes. Using culture medium of the rotifer Brachionus calyciflorus, phenotypic plasticity in Chlorella and Micractinium was studied. Non-bristled Micractinium cells developed bristles during incubation with Brachionus culture medium, whereas Chlorella did not produce bristles. Grazing experiments with Brachionus showed the rotifer preferred to feed on non-bristled cells. The dominance of colonies versus solitary cells in the Micractinium culture was not correlated with the "Brachionus factor". These results suggest that morphological characteristics like formation of bristles represent phenotypic adaptations to the conditions in the ecosystem.

  13. Conversion of membrane lipid acyl groups to triacylglycerol and formation of lipid bodies upon nitrogen starvation in biofuel green algae Chlorella UTEX29.

    PubMed

    Goncalves, Elton C; Johnson, Jodie V; Rathinasabapathi, Bala

    2013-11-01

    Algal lipids are ideal biofuel sources. Our objective was to determine the contributors to triacylglycerol (TAG) accumulation and lipid body formation in Chlorella UTEX29 under nitrogen (N) deprivation. A fivefold increase in intracellular lipids following N starvation for 24 h confirmed the oleaginous characteristics of UTEX29. Ultrastructural studies revealed increased number of lipid bodies and decreased starch granules in N-starved cells compared to N-replete cells. Lipid bodies were observed as early as 3 h after N removal and plastids collapsed after 48 h of stress. Moreover, the identification of intracellular pyrenoids and differences in the expected nutritional requirements for Chlorella protothecoides (as UTEX29 is currently classified) led us to conduct a phylogenetic study using 18S and actin cDNA sequences. This indicated UTEX29 to be more phylogenetically related to Chlorella vulgaris. To investigate the fate of different lipids after N starvation, radiolabeling using ¹⁴C-acetate was used. A significant decrease in ¹⁴C-galactolipids and phospholipids matched the increase in ¹⁴C-TAG starting at 3 h of N starvation, consistent with acyl groups from structural lipids as sources for TAG under N starvation. These results have important implications for the identification of key steps controlling oil accumulation in N-starved biofuel algae and demonstrate membrane recycling during lipid body formation.

  14. Structural Organization of DNA in Chlorella Viruses

    PubMed Central

    Wulfmeyer, Timo; Polzer, Christian; Hiepler, Gregor; Hamacher, Kay; Shoeman, Robert; Dunigan, David D.; Van Etten, James L.; Lolicato, Marco; Moroni, Anna; Thiel, Gerhard; Meckel, Tobias

    2012-01-01

    Chlorella viruses have icosahedral capsids with an internal membrane enclosing their large dsDNA genomes and associated proteins. Their genomes are packaged in the particles with a predicted DNA density of ca. 0.2 bp nm−3. Occasionally infection of an algal cell by an individual particle fails and the viral DNA is dynamically ejected from the capsid. This shows that the release of the DNA generates a force, which can aid in the transfer of the genome into the host in a successful infection. Imaging of ejected viral DNA indicates that it is intimately associated with proteins in a periodic fashion. The bulk of the protein particles detected by atomic force microscopy have a size of ∼60 kDa and two proteins (A278L and A282L) of about this size are among 6 basic putative DNA binding proteins found in a proteomic analysis of DNA binding proteins packaged in the virion. A combination of fluorescence images of ejected DNA and a bioinformatics analysis of the DNA reveal periodic patterns in the viral DNA. The periodic distribution of GC rich regions in the genome provides potential binding sites for basic proteins. This DNA/protein aggregation could be responsible for the periodic concentration of fluorescently labeled DNA observed in ejected viral DNA. Collectively the data indicate that the large chlorella viruses have a DNA packaging strategy that differs from bacteriophages; it involves proteins and share similarities to that of chromatin structure in eukaryotes. PMID:22359540

  15. Chlorella sorokiniana Extract Improves Short-Term Memory in Rats.

    PubMed

    Morgese, Maria Grazia; Mhillaj, Emanuela; Francavilla, Matteo; Bove, Maria; Morgano, Lucia; Tucci, Paolo; Trabace, Luigia; Schiavone, Stefania

    2016-09-29

    Increasing evidence shows that eukaryotic microalgae and, in particular, the green microalga Chlorella, can be used as natural sources to obtain a whole variety of compounds, such as omega (ω)-3 and ω-6 polyunsatured fatty acids (PUFAs). Although either beneficial or toxic effects of Chlorella sorokiniana have been mainly attributed to its specific ω-3 and ω-6 PUFAs content, the underlying molecular pathways remain to be elucidated yet. Here, we investigate the effects of an acute oral administration of a lipid extract of Chlorella sorokiniana, containing mainly ω-3 and ω-6 PUFAs, on cognitive, emotional and social behaviour in rats, analysing possible underlying neurochemical alterations. Our results showed improved short-term memory in Chlorella sorokiniana-treated rats compared to controls, without any differences in exploratory performance, locomotor activity, anxiety profile and depressive-like behaviour. On the other hand, while the social behaviour of Chlorella sorokiniana-treated animals was significantly decreased, no effects on aggressivity were observed. Neurochemical investigations showed region-specific effects, consisting in an elevation of noradrenaline (NA) and serotonin (5-HT) content in hippocampus, but not in the prefrontal cortex and striatum. In conclusion, our results point towards a beneficial effect of Chlorella sorokiniana extract on short-term memory, but also highlight the need of caution in the use of this natural supplement due to its possible masked toxic effects.

  16. Toxic effects of organic solvents on the growth of chlorella vulgaris and Selenastrum capicornutum

    SciTech Connect

    El Jay, A.

    1996-10-01

    Organic solvents can make their way into the environment as industrial wastes and components of pesticide formulations. In laboratory bioassays, the use of organic solvents is unavoidable since many pesticides and organic pollutants have low water solubilities and need to be dissolved in organic solvents prior to addition into experimental systems. So, one area of concern with laboratory bioassays is the stress imposed on test organisms by organic solvents. Most reports on the comparative toxicity of solvents towards test organisms deals with the effects of solvents on fish and aquatic invertebrates with some data available for blue-green algae and green algae. The US Environmental Protection Agency recommends maximum allowable limits of 0.05% solvent for acute tests and 0.01% for chronic tests but, in the literature, the nature of the solvent and the final concentration used vary among the different authors and are often higher than EPA limits due to problems associated with the use of small test volumes and toxicant solubility. Organic solvents can cause toxic effects on their own, but it has been also reported that they can interact with pesticides to alter toxicity. The first step in choosing a solvent for use in bioassays should be a detailed screening to identify solvents with inherently low toxicity to the test organism, followed by an interaction study (pesticide and solvent interactions) to choose the best concentration to use. The purpose of this study is to compare the inhibitory effects of our solvents used in pesticide bioassays towards the growth of two green algae. 18 refs., 4 figs., 1 tabs.

  17. BEHAVIORAL AND PHYSIOLOGICAL RESPONSES OF DAPHNIA MAGNA, CHLORELLA VULGARIS, LEPOMIS MACROCHIRUS, AND VIBRIO FISCHERI TO TOLUENE

    EPA Science Inventory

    The research presented here is a continuation of work designed to further the science of available and developing online toxicity monitors(OTMs) and how they may be most effectively deployed in a watershed management plan and/or water quality early warning system. Source waters o...

  18. BEHAVIORAL AND PHYSIOLOGICAL RESPONSES OF DAPHNIA MAGNA, CHLORELLA VULGARIS, CORBICULA FLUMINEA, LEPOMIS MACROCHIRUS, AND VIBRO FISCHERI

    EPA Science Inventory

    The research presented here is a continuation of work designed to further the science of available and developing continuous, automated water quality monitors and how they may be most effectively deployed in a watershed management plan and/or water quality early warning system (W...

  19. Electrochemical oxidation of the poultry manure anaerobic digested effluents for enhancing pollutants removal by Chlorella vulgaris.

    PubMed

    Wang, Mengzi; Cao, Wei; Wu, Yu; Lu, Haifeng; Li, Baoming

    2016-01-01

    The mechanisms and pseudo-kinetics of the electrochemical oxidation for wastewater treatment and the synergistic effect of combining algal biological treatment were investigated. NaCl, Na2SO4 and HCl were applied to compare the effect of electrolyte species on nutrients removal. NaCl was proved to be more efficient in removing ammonia ([Formula: see text]), total phosphorus (TP), total organic carbon (TOC) and inorganic carbon (IC). [Formula: see text] oxidation by using Ti/Pt-IrO2 electrodes was modelled, which indicates that the [Formula: see text] removal followed the zero-order kinetic with sufficient Cl(-) and the first-order kinetic with insufficient Cl(-), respectively. The feasibility of combining electrochemical oxidation with microalgae cultivation for wastewater treatment was also determined. A 2 h electrochemical pretreatment reduced 57% [Formula: see text], 76% TP, 72% TOC and 77% IC from the digested effluent, which is applied as feedstock for algae cultivation, and resulted in increasing both the biomass production and pollutants removal efficiencies of the algal biological process.

  20. Control of CO₂ input conditions during outdoor culture of Chlorella vulgaris in bubble column photobioreactors.

    PubMed

    Guo, Zhi; Phooi, Wei Boon Alfred; Lim, Zi Jian; Tong, Yen Wah

    2015-06-01

    A study on the optimization of CO2 usage during outdoor microalgae cultivation in order to further maximize the CO2 to biomass conversion efficiency is presented. A constant supply of CO2 was found to be non-essential for culturing microalgae outdoors in 80 L (8 L×10 sets) bubble columns. Among the different CO2 input conditions that were studied, 2% CO2 with intermittent supply and 2%+4% CO2 alternation did not affect the algal growth as compared to having a constant supply of 2% CO2. However, during both input conditions, the CO2 to biomass conversion efficiency was doubled while the amount of CO2 used was reduced by 50%. The algal biomass obtained was found to have a higher carbohydrate yield but a lower protein yield as compared to previously published studies. The findings from this study could be applied for large-scale microalgae production so as to minimize cultivation and energy costs.

  1. Nitrogen and Phosphorus Biomass-Kinetic Model for Chlorella vulgaris in a Biofuel Production Scheme

    DTIC Science & Technology

    2010-03-01

    oxygen and absorb carbon dioxide. They are considered photosynthetic , oxygenic autotrophs, because they use light energy to convert carbon dioxide...not masked by other pigments and both chlorophyll a and b are present. In addition they have β- and γ- carotene and several xanthophylls. These...The first stage was the appearance of new daughter cells followed by (2) the appearance of photosynthetically , chlorophyll- rich active cells, then

  2. Enhancement of Chlorella vulgaris harvesting via the electro-coagulation-flotation (ECF) method.

    PubMed

    Wong, Y K; Ho, Y H; Leung, H M; Ho, K C; Yau, Y H; Yung, K K L

    2016-12-30

    This article explores the potential of using an electro-coagulation-flotation (ECF) harvester to allow flotation of microalgae cells for surface harvesting. A response surface methodology (RSM) model was used to optimize ECF harvesting by adjusting electrode plate material, electrode plate number, charge of the electrodes, electrolyte concentration, and pH value of the culture solution. The result revealed that three aluminum electrode plates (one anode and two cathodes), brine solution (8 g/L), and acidity (pH = 4) of culture solution (optimized ECF harvester) The highest flocculant concentration was measured at 2966 mg/L after 60 min and showed a 79.8 % increase of flocculation concentration. Such results can provide a basis for designing a large-scale microalgae harvester for commercial use in the future.

  3. Weld arc simulator

    DOEpatents

    Burr, Melvin J.

    1990-01-30

    An arc voltage simulator for an arc welder permits the welder response to a variation in arc voltage to be standardized. The simulator uses a linear potentiometer connected to the electrode to provide a simulated arc voltage at the electrode that changes as a function of electrode position.

  4. Laser Activation of Rapid Absorption Changes in Spinach Chloroplasts and Chlorella 1

    PubMed Central

    Hildreth, W. W.; Avron, M.; Chance, B.

    1966-01-01

    The kinetics of the 520 mμ absorption change in spinach chloroplasts and Chlorella vulgaris following a flash from the ruby laser have been determined as follows: rise halftime ≤ 0.3 × 10−6 second; rapid recovery halftime = 5 to 6 × 10−6 second; intermediate recovery halftime = 4 × 10−4 second (spinach chloroplasts only); slow recovery halftime = 12 to 170 × 10−3 second, dependent on the measuring light intensity and aerobicity of the suspension. The rapid phase of the 520 mμ reaction is approximately independent of temperature, from 295° to 77° Absolute. With increasing oxygenation of the sample, the extent of the rapid phase decreases, the extent of the slow phase increases, while the extent of the intermediate phase in spinach chloroplasts remains constant. In spinach chloroplasts, no recovery halftime of the 3 recovery phases for the 520 mμ absorption change was observed to correspond to the halftime for oxidation of cytochrome f (t½ = 1.3 × 10−3 second). PMID:16656366

  5. Phaseolus vulgaris - recalcitrant potential.

    PubMed

    Hnatuszko-Konka, Katarzyna; Kowalczyk, Tomasz; Gerszberg, Aneta; Wiktorek-Smagur, Aneta; Kononowicz, Andrzej K

    2014-11-15

    Since the ability to genetically engineer plants was established, researchers have modified a great number of plant species to satisfy agricultural, horticultural, industrial, medicinal or veterinary requirements. Almost thirty years after the first approaches to the genetic modification of pulse crops, it is possible to transform many grain legumes. However, one of the most important species for human nutrition, Phaseolus vulgaris, still lacks some practical tools for genomic research, such as routine genetic transformation. Its recalcitrance towards in vitro regeneration and rooting significantly hampers the possibilities of improvement of the common bean that suffers from many biotic and abiotic constraints. Thus, an efficient and reproducible system for regeneration of a whole plant is desired. Although noticeable progress has been made, the rate of recovery of transgenic lines is still low. Here, the current status of tissue culture and recent progress in transformation methodology are presented. Some major challenges and obstacles are discussed and some examples of their solutions are presented.

  6. [Acne vulgaris: endocrine aspects].

    PubMed

    Dekkers, O M; Thio, B H; Romijn, J A; Smit, J W A

    2006-06-10

    Androgens play an important part in the development of acne vulgaris. Androgen levels in patients with acne are higher than those in controls and people with the androgen insensitivity syndrome do not develop acne. Local factors other than androgen plasma levels, also play a part in the development of acne. The skin contains enzymes that convert precursor hormones to the more potent androgens such as testosterone and dihydrotestosterone. Androgen synthesis can therefore be regulated locally. The effects of androgens on the skin are the result of circulating androgens and enzyme activity in local tissues and androgen receptors. Acne is a clinical manifestation of some endocrine diseases. The polycystic ovary syndrome has the highest prevalence. In women with acne that persists after puberty, in 10-200% of cases polycystic ovary syndrome is later diagnosed. The mechanism of hormonal anti-acne therapy may work by blocking the androgen-production (oestrogens) or by blocking the androgen receptor (cyproterone, spironolactone).

  7. Pyrroline-5-Carboxylate Reductase in Chlorella autotrophica and Chlorella saccharophila in Relation to Osmoregulation.

    PubMed

    Laliberté, G; Hellebust, J A

    1989-11-01

    Pyrroline-5-carboxylate (P5C) reductase (EC 1.5.1.2), which catalyzes the reduction of P5C to proline, was partially purified from two Chlorella species; Chlorella autotrophica, a euryhaline marine alga that responds to increases in salinity by accumulating proline and ions, and Chlorella saccharophila, which does not accumulate proline for osmoregulation. From the elution profile of this enzyme from an anion exchange column in Tris-HCl buffer (pH 7.6), containing sorbitol and glycine betaine, it was shown that P5C reductase from C. autotrophica was a neutral protein whereas the enzyme from C. saccharophila was negatively charged. The kinetic mechanisms of the reductase was characteristic of a ping-pong mechanism with double competitive substrate inhibition. Both enzymes showed high specificity for NADH as cofactor. The affinities of the reductases for their substrates did not change when the cells were grown at different salinities. In both algae, the apparent K(m) values of the reductase for P5C and NADH were 0.17 and 0.10 millimolar, respectively. A fourfold increase in maximal velocity of the reductase was observed when C. autotrophica was transferred from 50 to 150% artificial sea water. Even though the reductase was inhibited by NaCl, KCl, and proline, it still showed appreciable activity in the presence of these compounds at molar concentrations. A possible role for the regulation of proline synthesis at the step catalyzed by P5C reductase is discussed in relation to the specificity of P5C reductase for NADH and its responses to salt treatments.

  8. Gas arc constriction for plasma arc welding

    NASA Technical Reports Server (NTRS)

    McGee, William F. (Inventor); Rybicki, Daniel J. (Inventor)

    1994-01-01

    A welding torch for plasma arc welding apparatus has an inert gas applied circumferentially about the arc column externally of the constricting nozzle so as to apply a constricting force on the arc after it has exited the nozzle orifice and downstream of the auxiliary shielding gas. The constricting inert gas is supplied to a plenum chamber about the body of the torch and exits through a series of circumferentially disposed orifices in an annular wall forming a closure at the forward end of the constricting gas plenum chamber. The constricting force of the circumferential gas flow about the arc concentrates and focuses the arc column into a more narrow and dense column of energy after exiting the nozzle orifice so that the arc better retains its energy density prior to contacting the workpiece.

  9. Brain abscesses during Proteus vulgaris bacteremia.

    PubMed

    Bloch, Jennifer; Lemaire, Xavier; Legout, Laurence; Ferriby, Didier; Yazdanpanah, Yazdan; Senneville, Eric

    2011-08-01

    Proteus vulgaris is only rarely the cause of multiple septic metastases. We describe multiple brain abscesses due to P. vulgaris in an immunocompetent patient successfully treated by antibiotic therapy and colonectomy.

  10. Salt stimulated respiration of Chlorella fusca.

    PubMed

    Löppert, H G

    1976-01-01

    ATP contents have been measured before and after addition of KCl (5 mM final concentration) to suspensions of Chlorella in distilled water under different conditions of energy supply. The levels decreased immediately after salt addition and returned to the original values under conditions both of oxidative phosphorylation and of cyclic photophosphorylation, but not under conditions of fermentation. It appears that this decrease in the ATP level is the cause for salt stimulated respiration (S.S.R.). Furthermore, it is shown that cycloheximide and EDTA, which interact with Rb+ uptake (active and ATP-driven) at low salt concentration, also reduce S.S.R. From this parallelism it is concluded that the ATPase involved in Rb+ uptake at low salt concentration is also responsible for S.S.R. at high salt concentration. As S.S.R. provides far more energy than is required for the small influx of ions it is suggested that the ATPase is decoupled by the salt from ion transport.

  11. Culture of microalgae Chlorella minutissima for biodiesel feedstock production.

    PubMed

    Tang, Haiying; Chen, Meng; Garcia, M E D; Abunasser, Nadia; Ng, K Y Simon; Salley, Steven O

    2011-10-01

    Microalgae are among the most promising of non-food based biomass fuel feedstock alternatives. Algal biofuels production is challenged by limited oil content, growth rate, and economical cultivation. To develop the optimum cultivation conditions for increasing biofuels feedstock production, the effect of light source, light intensity, photoperiod, and nitrogen starvation on the growth rate, cell density, and lipid content of Chlorella minutissima were studied. The fatty acid content and composition of Chlorella minutissima were also investigated under the above conditions. Fluorescent lights were more effective than red or white light-emitting diodes for algal growth. Increasing light intensity resulted in more rapid algal growth, while increasing the period of light also significantly increased biomass productivity. Our results showed that the lipid and triacylglycerol content were increased under N starvation conditions. Thus, a two-phase strategy with an initial nutrient-sufficient reactor followed by a nutrient deprivation strategy could likely balance the desire for rapid and high biomass generation (124 mg/L) with a high oil content (50%) of Chlorella minutissima to maximize the total amount of oil produced for biodiesel production. Moreover, methyl palmitate (C16:0), methyl oleate (C18:1), methyl linoleate (C18:2), and methyl linolenate (C18:3) are the major components of Chlorella minutissima derived FAME, and choice of light source, intensity, and N starvation impacted the FAME composition of Chlorella minutissima. The optimized cultivation conditions resulted in higher growth rate, cell density, and oil content, making Chlorella minutissima a potentially suitable organism for biodiesel feedstock production.

  12. Pemphigus Vulgaris Presented with Cheilitis

    PubMed Central

    Safaie Naraghi, Zahra; Behrangi, Elham

    2014-01-01

    Background. Pemphigus vulgaris is an autoimmune blistering disease affecting the mucous membrane and skin. In 50 to 70% of cases, the initial manifestations of pemphigus vulgaris are oral lesions which may be followed by skin lesions. But it is unusual for the disease to present with initial and solitary persistent lower lip lesions without progression to any other location. Main Observations. We report a 41-year-old woman with dry crusted lesions only on the lower lip, clinically resembling actinic cheilitis and erosive lichen planus, but histopathological evaluation showed unexpected results of suprabasal acantholysis and cleft compatible with pemphigus vulgaris. We treated her with intralesional triamcinolone 10 mg/mL for 2 sessions and 2 g cellcept daily. Patient showed excellent response and lesions resolved completely within 2 months. In one-year follow-up, there was no evidence of relapse or any additional lesion on the other sites. Conclusion. Cheilitis may be the initial and sole manifestation of pemphigus vulgaris. Localized and solitary lesions of pemphigus vulgaris can be treated and controlled without systemic corticosteroids. PMID:25328720

  13. Rotating arc spark plug

    DOEpatents

    Whealton, John H.; Tsai, Chin-Chi

    2003-05-27

    A spark plug device includes a structure for modification of an arc, the modification including arc rotation. The spark plug can be used in a combustion engine to reduce emissions and/or improve fuel economy. A method for operating a spark plug and a combustion engine having the spark plug device includes the step of modifying an arc, the modifying including rotating the arc.

  14. DC arc weld starter

    DOEpatents

    Campiotti, Richard H.; Hopwood, James E.

    1990-01-01

    A system for starting an arc for welding uses three DC power supplies, a high voltage supply for initiating the arc, an intermediate voltage supply for sustaining the arc, and a low voltage welding supply directly connected across the gap after the high voltage supply is disconnected.

  15. Signalling pathways in pemphigus vulgaris.

    PubMed

    Li, Xiaoguang; Ishii, Norito; Ohata, Chika; Furumura, Minao; Hashimoto, Takashi

    2014-03-01

    Acantholysis in pemphigus vulgaris is induced by binding of autoantibodies to desmoglein 3 (Dsg3). The roles of signalling pathways on development of acantholysis have recently been extensively studied. In the study by Sayar et al., recently published in Exp Dermatol, epidermal growth factor receptor (EGFR) signalling was activated in both in vivo and in vitro pemphigus vulgaris experimental models. However, while EGFR inhibitors suppressed activity of p38 mitogen-activated protein kinase (p38MAPK) linearly, they suppressed activity of c-Myc and acantholysis in a non-linear, V-shaped relationship. These findings indicated complicated interactions among EGFR, p38MAPK and c-Myc in pemphigus vulgaris pathology.

  16. Pemphigus Vulgaris with Tense Bullae

    PubMed Central

    Nguyen, Emilie T; Lin, Shinko K; Wu, Jashin J

    2015-01-01

    We report a case of a 51-year-old woman with a history of type II diabetes mellitus and dyslipidemia presenting with pain, swelling, and crusting of the lips. One year after onset of mucosal lesions, she developed an abdominal eruption with several tense vesicles and bullae on an erythematous base. The hematoxylin and eosin stain sample was consistent with a diagnosis of pemphigus vulgaris. The tense bullae of our patient highlight a rare phenotype of pemphigus vulgaris, which fits the mucocutaneous type because of involvement of the oral mucosa, with the exception of the findings of tense bullae. PMID:25663209

  17. Pemphigus vulgaris with tense bullae.

    PubMed

    Nguyen, Emilie T; Lin, Shinko K; Wu, Jashin J

    2015-01-01

    We report a case of a 51-year-old woman with a history of type II diabetes mellitus and dyslipidemia presenting with pain, swelling, and crusting of the lips. One year after onset of mucosal lesions, she developed an abdominal eruption with several tense vesicles and bullae on an erythematous base. The hematoxylin and eosin stain sample was consistent with a diagnosis of pemphigus vulgaris. The tense bullae of our patient highlight a rare phenotype of pemphigus vulgaris, which fits the mucocutaneous type because of involvement of the oral mucosa, with the exception of the findings of tense bullae.

  18. Comparison of biomass and lipid production under ambient carbon dioxide vigorous aeration and 3% carbon dioxide condition among the lead candidate Chlorella strains screened by various photobioreactor scales.

    PubMed

    Kobayashi, Naoko; Barnes, Austin; Jensen, Travis; Noel, Eric; Andlay, Gunjan; Rosenberg, Julian N; Betenbaugh, Michael J; Guarnieri, Michael T; Oyler, George A

    2015-12-01

    Chlorella species from the UTEX collection, classified by rDNA-based phylogenetic analysis, were screened based on biomass and lipid production in different scales and modes of culture. The lead candidate strains of C. sorokiniana UTEX 1230 and C. vulgaris UTEX 395 and 259 were compared between conditions of vigorous aeration with filtered atmospheric air and 3% CO2 shake-flask cultivation. The biomass of UTEX 1230 produced 2 times higher at 652 mg L(-1) dry weight under both ambient CO2 vigorous aeration and 3% CO2 conditions, while UTEX 395 and 259 under 3% CO2 increased to 3 times higher at 863 mg L(-1) dry weight than ambient CO2 vigorous aeration. The triacylglycerol contents of UTEX 395 and 259 increased more than 30 times to 30% dry weight with 3% CO2, indicating that additional CO2 is essential for both biomass and lipid accumulation in UTEX 395 and 259.

  19. Comparative Analyses of Three Chlorella Species in Response to Light and Sugar Reveal Distinctive Lipid Accumulation Patterns in the Microalga C. sorokiniana

    PubMed Central

    Barnes, Austin; Noel, Eric A.; Betenbaugh, Michael J.; Oyler, George A.

    2014-01-01

    While photosynthetic microalgae, such as Chlorella, serve as feedstocks for nutritional oils and biofuels, heterotrophic cultivation can augment growth rates, support high cell densities, and increase triacylglycerol (TAG) lipid content. However, these species differ significantly in their photoautotrophic and heterotrophic characteristics. In this study, the phylogeny of thirty Chlorella strains was determined in order to inform bioprospecting efforts and detailed physiological assessment of three species. The growth kinetics and lipid biochemistry of C. protothecoides UTEX 411, C. vulgaris UTEX 265, and C. sorokiniana UTEX 1230 were quantified during photoautotrophy in Bold's basal medium (BBM) and heterotrophy in BBM supplemented with glucose (10 g L−1). Heterotrophic growth rates of UTEX 411, 265, and 1230 were found to be 1.5-, 3.7-, and 5-fold higher than their respective autotrophic rates. With a rapid nine-hour heterotrophic doubling time, Chlorella sorokiniana UTEX 1230 maximally accumulated 39% total lipids by dry weight during heterotrophy compared to 18% autotrophically. Furthermore, the discrete fatty acid composition of each strain was examined in order to elucidate lipid accumulation patterns under the two trophic conditions. In both modes of growth, UTEX 411 and 265 produced 18∶1 as the principal fatty acid while UTEX 1230 exhibited a 2.5-fold enrichment in 18∶2 relative to 18∶1. Although the total lipid content was highest in UTEX 411 during heterotrophy, UTEX 1230 demonstrated a two-fold increase in its heterotrophic TAG fraction at a rate of 28.9 mg L−1 d−1 to reach 22% of the biomass, corresponding to as much as 90% of its total lipids. Interestingly, UTEX 1230 growth was restricted during mixotrophy and its TAG production rate was suppressed to 18.2 mg L−1 d−1. This constraint on carbon flow raises intriguing questions about the impact of sugar and light on the metabolic regulation of microalgal lipid biosynthesis. PMID:24699196

  20. Comparative analyses of three Chlorella species in response to light and sugar reveal distinctive lipid accumulation patterns in the Microalga C. sorokiniana.

    PubMed

    Rosenberg, Julian N; Kobayashi, Naoko; Barnes, Austin; Noel, Eric A; Betenbaugh, Michael J; Oyler, George A

    2014-01-01

    While photosynthetic microalgae, such as Chlorella, serve as feedstocks for nutritional oils and biofuels, heterotrophic cultivation can augment growth rates, support high cell densities, and increase triacylglycerol (TAG) lipid content. However, these species differ significantly in their photoautotrophic and heterotrophic characteristics. In this study, the phylogeny of thirty Chlorella strains was determined in order to inform bioprospecting efforts and detailed physiological assessment of three species. The growth kinetics and lipid biochemistry of C. protothecoides UTEX 411, C. vulgaris UTEX 265, and C. sorokiniana UTEX 1230 were quantified during photoautotrophy in Bold's basal medium (BBM) and heterotrophy in BBM supplemented with glucose (10 g L-1). Heterotrophic growth rates of UTEX 411, 265, and 1230 were found to be 1.5-, 3.7-, and 5-fold higher than their respective autotrophic rates. With a rapid nine-hour heterotrophic doubling time, Chlorella sorokiniana UTEX 1230 maximally accumulated 39% total lipids by dry weight during heterotrophy compared to 18% autotrophically. Furthermore, the discrete fatty acid composition of each strain was examined in order to elucidate lipid accumulation patterns under the two trophic conditions. In both modes of growth, UTEX 411 and 265 produced 18:1 as the principal fatty acid while UTEX 1230 exhibited a 2.5-fold enrichment in 18:2 relative to 18:1. Although the total lipid content was highest in UTEX 411 during heterotrophy, UTEX 1230 demonstrated a two-fold increase in its heterotrophic TAG fraction at a rate of 28.9 mg L(-1) d(-1) to reach 22% of the biomass, corresponding to as much as 90% of its total lipids. Interestingly, UTEX 1230 growth was restricted during mixotrophy and its TAG production rate was suppressed to 18.2 mg L-1 d-1. This constraint on carbon flow raises intriguing questions about the impact of sugar and light on the metabolic regulation of microalgal lipid biosynthesis.

  1. Screening and characterization of oleaginous Chlorella strains and exploration of photoautotrophic Chlorella protothecoides for oil production.

    PubMed

    Sun, Zheng; Zhou, Zhi-gang; Gerken, Henri; Chen, Feng; Liu, Jin

    2015-05-01

    The growth and oil production of nine Chlorella strains were comparatively assessed and Chlorellaprotothecoides CS-41 demonstrated the greatest lipid production potential. The effects of different nitrogen forms and concentrations, phosphorus concentrations and light intensities on growth and oil production were studied in laboratory columns. C. protothecoides CS-41 accumulated lipids up to 55% of dry weight, with triacylglycerol and oleic acid being 71% of total lipids and 59% of total fatty acids, respectively. High biomass and lipid productivities were achieved in outdoor panel PBRs, up to 1.25 and 0.59 g L(-1) day(-1), or 44. 1 and 16.1 g m(-2) day(-1), respectively. A two-stage cultivation strategy was proposed to enhance the algal biomass and lipid production. This is the first comprehensive investigation of both indoor and outdoor photoautotrophic C. protothecoides cultures for oil production, and C. protothecoides CS-41 represents a promising biofuel feedstock worthy of further exploration.

  2. Chlorella protects against hydrogen peroxide-induced pancreatic β-cell damage.

    PubMed

    Lin, Chia-Yu; Huang, Pei-Jane; Chao, Che-Yi

    2014-12-01

    Oxidative stress has been implicated in the etiology of pancreatic β-cell dysfunction and diabetes. Studies have shown that chlorella could be important in health promotion or disease prevention through its antioxidant capacity. However, whether chlorella has a cytoprotective effect in pancreatic β-cells remains to be elucidated. We investigated the protective effects of chlorella on H2O2-induced oxidative damage in INS-1 (832/13) cells. Chlorella partially restored cell viability after H2O2 toxicity. To further investigate the effects of chlorella on mitochondria function and cellular oxidative stress, we analyzed mitochondria membrane potential, ATP concentrations, and cellular levels of reactive oxygen species (ROS). Chlorella prevented mitochondria disruption and maintained cellular ATP levels after H2O2 toxicity. It also normalized intracellular levels of ROS to that of control in the presence of H2O2. Chlorella protected cells from apoptosis as indicated by less p-Histone and caspase 3 activation. In addition, chlorella not only enhanced glucose-stimulated insulin secretion (GSIS), but also partially restored the reduced GSIS after H2O2 toxicity. Our results suggest that chlorella is effective in amelioration of cellular oxidative stress and destruction, and therefore protects INS-1 (832/13) cells from H2O2-induced apoptosis and increases insulin secretion. Chlorella should be studied for use in the prevention or treatment of diabetes.

  3. Chlorella species as hosts for genetic engineering and expression of heterologous proteins: Progress, challenge and perspective.

    PubMed

    Yang, Bo; Liu, Jin; Jiang, Yue; Chen, Feng

    2016-10-01

    The species of Chlorella represent a highly specialized group of green microalgae that can produce high levels of protein. Many Chlorella strains can grow rapidly and achieve high cell density under controlled conditions and are thus considered to be promising protein sources. Many advances in the genetic engineering of Chlorella have occurred in recent years, with significant developments in successful expression of heterologous proteins for various applications. Nevertheless, a lot of obstacles remain to be addressed, and a sophisticated and stable Chlorella expression system has yet to emerge. This review provides a brief summary of current knowledge on Chlorella and an overview of recent progress in the genetic engineering of Chlorella, and highlights the advances in the development of a genetic toolbox of Chlorella for heterologous protein expression. Research directions to further exploit the Chlorella expression system with respect to both challenges and perspectives are also discussed. This paper serves as a comprehensive literature review for the Chlorella community and will provide valuable insights into future exploration of Chlorella as a promising host for heterologous protein expression.

  4. Utilization of papaya waste and oil production by Chlorella protothecoides

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Algae derived oils have outstanding potential for use in biodiesel production. Chlorella protothecoides has been shown to accumulate lipid up to 60% of its cellular dry weight with glucose supplementation under heterotrophic growth conditions. To reduce production costs, alternative carbon feedstock...

  5. Uptake and bioaccumulation of three PCBs by Chlorella fusca

    SciTech Connect

    Wang, K.; Rott, B.; Korte, F.

    1982-01-01

    This paper reports the bioaccumulation of three PCBs (2,4'-dichlorobiphenyl, 2,4,6,2'-tetrachlorobiphenyl and 2,4,6,2',4'-pentachlorobiphenyl) by the green alga Chlorella fusca under various conditions. A probable pattern of the bioconcentration mechanism is suggested. No metabolites were extracted from algae or water 6 days after incubation with PCBs.

  6. Evaluation of Chlorella as a Decorporation Agent to Enhance the Elimination of Radioactive Strontium from Body

    PubMed Central

    Ogawa, Kazuma; Fukuda, Tadahisa; Han, Jaegab; Kitamura, Yoji; Shiba, Kazuhiro; Odani, Akira

    2016-01-01

    Background Release of radionuclides, such as 137Cs and 90Sr, into the atmosphere and the ocean presents an important problem because internal exposure to 137Cs and 90Sr could be very harmful to humans. Chlorella has been reported to be effective in enhancing the excretion of heavy metals; thus, we hypothesized that Chlorella could also enhance the elimination of 137Cs or 90Sr from the body. We evaluated the potential of Chlorella as a decorporation agent in vitro and in vivo, using 85Sr instead of 90Sr. Methods In vitro experiments of adsorption of 137Cs and 85Sr to Chlorella were performed under wide pH conditions. The maximum sorption capacity of Chlorella to strontium was estimated using the Langmuir model. A 85Sr solution was orally administrated to mice pretreated with Chlorella. At 48 h after 85Sr administration, the biodistribution of radioactivity was determined. Results In the in vitro experiments, although 85Sr barely adsorbed to Chlorella at low pH, the 85Sr adsorption ratio to Chlorella increased with increasing pH. The maximum sorption capacity of Chlorella to strontium was 9.06 mg / g. 137Cs barely adsorbed to Chlorella under any pH conditions. In the biodistribution experiments, bone accumulation of radioactivity after 85Sr administration was significantly decreased in the Chlorella pretreatment group compared with the non-treatment control group. Conclusions In conclusion, these results indicated that Chlorella could inhibit the absorption of 90Sr into the blood and enhance the elimination of 90Sr from the body through adsorption in intestine. Further studies are required to elucidate the mechanism and the components of Chlorella needed for adsorption to strontium and could promote the development of more effective decorporation agents. PMID:26828430

  7. Rethinking Recycling in Arcs

    NASA Astrophysics Data System (ADS)

    Kelemen, P.; Behn, M. D.; Jagoutz, O.

    2012-12-01

    Hacker et al EPSL 2011 and Behn et al Nature Geosci 2011 investigated pathways for return of buoyant, subducted material to arc crust. These include (1) diapirs rising into the hot mantle wedge, with extensive melts adding a component to arc magmas, (2) flow of material back up a relatively cold "subduction channel", adding solids to the lower crust and small-degree partial melts to the upper crust, (3) flow from the forearc along the base of arc crust, and (4) imbrication of forearc material into arc crust. These processes add felsic, incompatible-element-rich components to arc crust. The flux of incompatible elements such as Th in arc lavas, thought to be mainly recycled from subducted sediments, is > sediment subduction flux. There are large uncertainties: arc crustal growth rates are imprecise; young, primitive arc lavas may not be representative of magmatic flux into arc crust; sediment subduction flux may have varied. Nevertheless, this result is found for all arcs examined, using recently published growth rates. Perhaps arc growth rates that include subduction erosion are systematically overestimated. Instead or in addition, maybe significant Th comes from material other than sediments. Here, we consider the implications of pathways 1-4 for arc growth rates and incompatible element enrichment, in the context of subduction erosion and arc-arc collision. Subducting arc lithologies can become separated, with only felsic components returned to arc crust. Buoyant lithologies are mobile in viscous instabilities at > 700-800°C. Whereas thin layers such as sediments may become mobile all at once, instabilities may periodically strip the hottest parts from the top of thick buoyant layers, replacing them with hot mantle. In arc-arc collision, the top of a subducting plate starts at about 0°C on the seafloor, so heating is slow. In subduction erosion, forearc material in the subducting package can be > 200°C before erosion so buoyant lithologies reach 700-800

  8. Arc initiation in cathodic arc plasma sources

    SciTech Connect

    Anders, Andre

    2002-01-01

    A "triggerless" arc initiation method and apparatus is based on simply switching the arc supply voltage to the electrodes (anode and cathode). Neither a mechanical trigger electrode nor a high voltage flashover from a trigger electrode is required. A conducting path between the anode and cathode is provided, which allows a hot spot to form at a location where the path connects to the cathode. While the conductive path is eroded by the cathode spot action, plasma deposition ensures the ongoing repair of the conducting path. Arc initiation is achieved by simply applying the relatively low voltage of the arc power supply, e.g. 500 V-1 kV, with the insulator between the anode and cathode coated with a conducting layer and the current at the layer-cathode interface concentrated at one or a few contact points. The local power density at these contact points is sufficient for plasma production and thus arc initiation. A conductive surface layer, such as graphite or the material being deposited, is formed on the surface of the insulator which separates the cathode from the anode. The mechanism of plasma production (and arc initiation) is based on explosive destruction of the layer-cathode interface caused by joule heating. The current flow between the thin insulator coating and cathode occurs at only a few contact points so the current density is high.

  9. [Research status and prospect on hot water extract of Chlorella: the high value-added bioactive substance from Chlorella].

    PubMed

    Zhuang, Xiuyuan; Huang, Yingming; Zhang, Daojing; Tao, Liming; Li, Yuanguang

    2015-01-01

    Chlorella is nutritious and has been used as a functional food much earlier than the other microalgae. C. pyrenoidosa, the potential microalgae which is currently cultured and developed for the new strategic industry of biofuels production and biological CO2 fixation, is a new resource food announced by the Ministry of Health of the People's Republic of China late 2012. Accumulation of high value-added substances in C. pyrenoidosa during the cultivation for lipid makes it possible to reduce the costs for C. pyrenoidosa-based biofuels production. Among these potential substances, hot water extract of Chlorella (CE), commercially known as "Chlorella growth factor", is the unique one that makes Chlorella more precious than the other algae, and the market price of CE is high. It is believed that CE is effective in growth promotion and immunoregulation. However, there is no systematic analysis on the research status of CE and its bioactivity. The present report summarized recent research progress of CE and its bioactivity. Generally, besides the main effect on immunoregulation and tumor inhibition, CE was efficient in improving metabolic syndrome, scavenging for free radicals, protecting against ultraviolet damage, chelating heavy metals, and protecting liver and bowel. Several major challenges in CE research as well as its prospects were also analysed in the present report.

  10. Disseminated lupus vulgaris.

    PubMed

    Garg, Taru; Ramchander; Shrihar, Rashmi; Gupta, Tanvi Pal; Aggarwal, Shilpi

    2011-01-01

    follicular plugging and multiple epithelioid cell granulomas, rimmed by lymphocytes in the deeper portion of the dermis, mainly peri-appendageal. Stain for acid-fast bacteria was negative. Cultures from the skin lesions were negative. The patient was diagnosed as having lupus vulgaris with multiple lesions of varying morphology at different sites with pulmonary tuberculosis and healed lymph node involvement.

  11. Comparative transcriptomic analysis reveals phenol tolerance mechanism of evolved Chlorella strain.

    PubMed

    Zhou, Lin; Cheng, Dujia; Wang, Liang; Gao, Juan; Zhao, Quanyu; Wei, Wei; Sun, Yuhan

    2017-03-01

    The growth of microalgae is inhibited by high concentration phenol due to reactive oxygen species. An evolved strain tolerated to 500mg/L phenol, Chlorella sp. L5, was obtained in previous study. In this study, comparative transcriptomic analysis was performed for Chlorella sp. L5 and its original strain (Chlorella sp. L3). The tolerance mechanism of Chlorella sp. L5 for high concentration phenol was explored on genome scale. It was identified that the up-regulations of the related genes according to antioxidant enzymes (SOD, APX, CAT and GR) and carotenoids (astaxanthin, lutein and lycopene) biosynthesis had critical roles to tolerate high concentration phenol. In addition, most of genes of PS I, PS II, photosynthetic electron transport chain and starch biosynthesis were also up-regulated. It was consistent to the experimental results of total carbohydrate contents of Chlorella sp. L3 and Chlorella sp. L5 under 0mg/L and 500mg/L phenol.

  12. Long arc stabilities with various arc gas flow rates

    NASA Astrophysics Data System (ADS)

    Maruyama, K.; Takeda, K.; Sugimoto, M.; Noguchi, Y.

    2014-11-01

    A new arc torch for use in magnetically driven arc device was developed with a commercially available TIG welding arc torch. The torch has a water-cooling system to the torch nozzle and has a nozzle nut to supply a swirling-free plasma gas flow. Its endurance against arc thermal load is examined. Features of its generated arc are investigated.

  13. STUDIES ON THE CHANGE OF THE CONCENTRATIONS OF INTERMEDIATES DURING PHOTOSYNTHESIS OF CHLORELLA AND ISOLATED CHLOROPLASTS.

    DTIC Science & Technology

    The chages in the concentrations of intermediates and the distribution of C(14) after photosynthesis in C(14)02 by Chlorella and isolated...changes in the concentrations of intermediates in Chlorella during the transition from light to dark and vice versa are independent of CO2, but...dependent on anaerobiosis. (2) In Chlorella photosynthesis is inhibited even by a concentration of monoiodoacetic acid which is 100 times lower than that

  14. Welding arc plasma physics

    NASA Technical Reports Server (NTRS)

    Cain, Bruce L.

    1990-01-01

    The problems of weld quality control and weld process dependability continue to be relevant issues in modern metal welding technology. These become especially important for NASA missions which may require the assembly or repair of larger orbiting platforms using automatic welding techniques. To extend present welding technologies for such applications, NASA/MSFC's Materials and Processes Lab is developing physical models of the arc welding process with the goal of providing both a basis for improved design of weld control systems, and a better understanding of how arc welding variables influence final weld properties. The physics of the plasma arc discharge is reasonably well established in terms of transport processes occurring in the arc column itself, although recourse to sophisticated numerical treatments is normally required to obtain quantitative results. Unfortunately the rigor of these numerical computations often obscures the physics of the underlying model due to its inherent complexity. In contrast, this work has focused on a relatively simple physical model of the arc discharge to describe the gross features observed in welding arcs. Emphasis was placed of deriving analytic expressions for the voltage along the arc axis as a function of known or measurable arc parameters. The model retains the essential physics for a straight polarity, diffusion dominated free burning arc in argon, with major simplifications of collisionless sheaths and simple energy balances at the electrodes.

  15. Extensive keloid formation after pemphigus vulgaris.

    PubMed

    Sako, Eric Y; Workwick, Scott

    2015-11-18

    Pemphigus vulgaris is an immunobullous disease characterized by intraepidermal blister formation. These blisters eventually rupture, leaving erosions that are slow to heal, often leaving hyperpigmented patches, but no scars. We describe a case of a 67- year-old man with pemphigus vulgaris who suffered severe keloidal scarring after the pemphigus lesions became infected. His keloids were treated with intralesional corticosteroids with some improvement. Pemphigus vulgaris, a process confined to the epidermis, may lead to scarring in predisposed individuals, particularly if infection occurs.

  16. [Therapy-resistant "psoriasis vulgaris"].

    PubMed

    Kempter, W; Stein, A; Bauer, A; Wozel, G

    2009-04-01

    A 61-year-old patient had a 25-year history of erythematous scaling lesions, diagnosed and treated as psoriasis vulgaris. He presented with a growing nodule within the erythematous plaque. Biopsy shows epithelioid cell granulomas with prominent Langhans giant cells. There was no sign of a squamous cell carcinoma. The tuberculin test was strongly positive and M. tuberculosis complex was detected in the biopsy material by PCR. He was diagnosed with lupus vulgaris, the most frequent form of cutaneous tuberculosis. Other types include tuberculosis verrucosa cutis, tuberculosis cutis orificialis and disseminated military tuberculosis. The patient was treated with rifampicin, isoniazid, pyrazinamide and ethambutol for two months, following a four month treatment with rifampicin and isoniazid. The skin lesions rapidly resolved under antituberculotic treatment.

  17. WSTF electrical arc projects

    NASA Astrophysics Data System (ADS)

    Linley, Larry

    1994-09-01

    The objectives of these projects include the following: validate method used to screen wire insulation with arc tracking characteristics; determine damage resistance to arc as a function of source voltage and insulation thickness; investigate propagation characteristics of Kapton at low voltages; and investigate pyrolytic properties of polyimide insulated (Kapton) wire for low voltage (less than 35 VDC) applications. Supporting diagrams and tables are presented.

  18. WSTF electrical arc projects

    NASA Technical Reports Server (NTRS)

    Linley, Larry

    1994-01-01

    The objectives of these projects include the following: validate method used to screen wire insulation with arc tracking characteristics; determine damage resistance to arc as a function of source voltage and insulation thickness; investigate propagation characteristics of Kapton at low voltages; and investigate pyrolytic properties of polyimide insulated (Kapton) wire for low voltage (less than 35 VDC) applications. Supporting diagrams and tables are presented.

  19. TIGER Arc Modification Application

    SciTech Connect

    Armstrong, Hillary

    1995-03-06

    The application enables the geometric correction of TIGER arcs to a more accurate spatial data set. This is done in a structured automated environment according to Census Bureau guidelines and New Mexico state GIS standards. Arcs may be deleted, added, combined, split, and moved relative to a coverage or image displayed in the background.

  20. Biosorption of Lead from Wastewater Using Fresh Water Algae Chlorella.

    PubMed

    Kanchana, S; Jeyanthi, J

    2014-04-01

    The potential use of fresh water algae Chlorella to sorb lead ions from wastewater was evaluated in this study. Fourier transform infra-red analysis of algal species revealed the presence of amino, carboxylic, hydroxyl and carbonyl groups, which were responsible for biosorption of lead ions. Batch sorption experiments were performed to determine the effects of contact time, biosorbent dosage and pH on the adsorption of Pb2+ ions. The optimum conditions of biosorbent dosage, pH and contact time were found to be l0 g/L, 5 and 100 min respectively. The applicability of the Langmuir and Freundlich isotherms for representation of the experimental data was investigated. The adsorption of lead ions on the algae Chlorella fitted well with Freundlich isotherm with a very high correlation coefficient.

  1. Lazy arc consistency

    SciTech Connect

    Schiex, T.; Gaspin, C.; Regin, J.C.; Verfaillie, G.

    1996-12-31

    Arc consistency filtering is widely used in the framework of binary constraint satisfaction problems: with a low complexity, inconsistency may be detected and domains are filtered. In this paper, we show that when detecting inconsistency is the objective, a systematic domain filtering is useless and a lazy approach is more adequate. Whereas usual arc consistency algorithms produce the maximum arc consistent sub-domain, when it exists, we propose a method, called LAC{tau}, which only looks for any arc consistent sub-domain. The algorithm is then extended to provide the additional service of locating one variable with a minimum domain cardinality in the maximum arc consistent sub-domain, without necessarily computing all domain sizes. Finally, we compare traditional AC enforcing and lazy AC enforcing using several benchmark problems, both randomly generated CSP and real life problems.

  2. Autoimmunity to desmocollin 3 in pemphigus vulgaris.

    PubMed

    Mao, Xuming; Nagler, Arielle R; Farber, Sara A; Choi, Eun Jung; Jackson, Lauren H; Leiferman, Kristin M; Ishii, Norito; Hashimoto, Takashi; Amagai, Masayuki; Zone, John J; Payne, Aimee S

    2010-12-01

    Pemphigus vulgaris is a blistering disease associated with autoantibodies to the desmosomal adhesion protein, desmoglein 3. Genetic deficiency of desmoglein 3 in mice mimics autoimmunity to desmoglein 3 in pemphigus vulgaris, with mucosal-dominant blistering in the suprabasal layer of the epidermis. Mice with an epidermal-specific deletion of desmocollin 3, the other major desmosomal cadherin isoform expressed in the basal epidermis, develop suprabasal blisters in skin that are histologically identical to those observed in pemphigus vulgaris, suggesting that desmocollin 3 might be a target of autoantibodies in some pemphigus vulgaris patients. We now demonstrate that desmocollin 3 is an autoantigen in pemphigus vulgaris, illustrated in a patient with mucosal-dominant blistering. Six of 38 pemphigus vulgaris and one of 85 normal serum samples immunoprecipitate desmocollin 3 (P = 0.003). Incubation of patient IgG with human keratinocytes causes loss of intercellular adhesion, and adsorption with recombinant desmocollin 3 specifically prevents this pathogenic effect. Additionally, anti-desmocollin 3 sera cause loss of keratinocyte cell surface desmocollin 3, but not desmoglein 3 by immunofluorescence, indicating distinct cellular pathogenic effects in anti-desmocollin and anti-desmoglein pemphigus, despite their identical clinical presentations. These data demonstrate that desmocollin 3 is a pathogenic autoantigen in pemphigus vulgaris and suggest that pemphigus vulgaris is a histological reaction pattern that may result from autoimmunity to desmoglein 3, desmocollin 3, or both desmosomal cadherins.

  3. Sporotrichoid lupus vulgaris: A rare presentation.

    PubMed

    Maheshwari, Anshul; Tiwari, Siddhi; Mathur, Deepak K; Bhargava, Puneet

    2015-01-01

    Lupus vulgaris is the most common presentation of cutaneous tuberculosis in India and can present as papular, nodular, plaque, ulcerative, vegetating, and tumid forms. Unusual variants include the frambesiform, gangrenous, ulcerovegetating, lichen simplex chronicus, myxomatous, and sporotrichoid types. We describe a rare sporotrichoid presentation of lupus vulgaris on the leg of a 28-year-old female of 12 years duration.

  4. Pemphigus vulgaris with solitary toxic thyroid nodule.

    PubMed

    Alfishawy, Mostafa; Anwar, Karim; Elbendary, Amira; Daoud, Ahmed

    2014-01-01

    Background. Pemphigus vulgaris is an autoimmune vesiculobullous disease, affecting the skin and mucous membranes. It is reported to be associated with other autoimmune diseases including autoimmune thyroid diseases. However we report herein a case of pemphigus vulgaris associated with autonomous toxic nodule. Case Presentation. A 51-year-old woman was evaluated for blisters and erosions that develop on her trunk, face, and extremities, with a five-year history of progressively enlarging neck mass, and a past medical history of pemphigus vulgaris seven years ago. The condition was associated with palpitation, dyspnea, and heat intolerance. Thyroid function tests and thyroid scan were compatible with the diagnosis of thyrotoxicosis due to autonomous toxic nodule. Exacerbation of pemphigus vulgaris was proved by skin biopsy from the patient which revealed histologic picture of pemphigus vulgaris. Conclusion. Autoimmune thyroid diseases are reported to associate pemphigus vulgaris. To our knowledge, this case is the first in the English literature to report association between pemphigus vulgaris and autonomous toxic nodule and highlights the possibility of occurrence of pemphigus vulgaris with a nonautoimmune thyroid disease raising the question: is it just a coincidence or is there an explanation for the occurrence of both conditions together?

  5. Lupus vulgaris with squamous cell carcinoma.

    PubMed

    Motswaledi, Mojakgomo Hendrick; Doman, Chantal

    2007-12-01

    Tuberculosis is still a significant problem in developing countries. Cutaneous forms of tuberculosis account for approximately 10% of all cases of extrapulmonary tuberculosis. Cutaneous tuberculosis may be because of true infection with Mycobacterium tuberculosis or because of tuberculids. Tuberculids are immunological reactions to haematogenously spread antigenic components of M. tuberculosis. True cutaneous tuberculosis may be because of inoculation or haematogenous spread of M. tuberculosis to the skin. Lupus vulgaris is the commonest form of true cutaneous tuberculosis. Other forms of true cutaneous tuberculosis are tuberculous chancre, tuberculosis verrucosa cutis, scrofuloderma, periorificial tuberculosis and miliary tuberculosis of the skin. Lupus vulgaris is usually chronic and progressive. It occurs in patients with moderate to high immunity against M. tuberculosis as evidenced by strongly positive tuberculin test. Long-standing cases of lupus vulgaris may be complicated by squamous cell carcinoma (SCC). We describe a patient who had undiagnosed lupus vulgaris for 35 years until she developed SCC on the lesion of lupus vulgaris.

  6. Tokamak ARC damage

    SciTech Connect

    Murray, J.G.; Gorker, G.E.

    1985-01-01

    Tokamak fusion reactors will have large plasma currents of approximately 10 MA with hundreds of megajoules stored in the magnetic fields. When a major plasma instability occurs, the disruption of the plasma current induces voltage in the adjacent conducting structures, giving rise to large transient currents. The induced voltages may be sufficiently high to cause arcing across sector gaps or from one protruding component to another. This report reviews a tokamak arcing scenario and provides guidelines for designing tokamaks to minimize the possibility of arc damage.

  7. Electric arc saw apparatus

    DOEpatents

    Deichelbohrer, Paul R [Richland, WA

    1986-01-01

    A portable, hand held electric arc saw has a small frame for supporting an electrically conducting rotary blade which serves as an electrode for generating an electric arc to erode a workpiece. Electric current is supplied to the blade by biased brushes and a slip ring which are mounted in the frame. A pair of freely movable endless belts in the form of crawler treads stretched between two pulleys are used to facilitate movement of the electric arc saw. The pulleys are formed of dielectric material to electrically insulate the crawler treads from the frame.

  8. Welding arc initiator

    DOEpatents

    Correy, Thomas B.

    1989-01-01

    An improved inert gas shielded tungsten arc welder is disclosed of the type wherein a tungsten electrode is shielded within a flowing inert gas, and, an arc, following ignition, burns between the energized tungsten electrode and a workpiece. The improvement comprises in combination with the tungsten electrode, a starting laser focused upon the tungsten electrode which to ignite the electrode heats a spot on the energized electrode sufficient for formation of a thermionic arc. Interference problems associated with high frequency starters are thus overcome.

  9. Welding arc initiator

    DOEpatents

    Correy, T.B.

    1989-05-09

    An improved inert gas shielded tungsten arc welder is disclosed of the type wherein a tungsten electrode is shielded within a flowing inert gas, and, an arc, following ignition, burns between the energized tungsten electrode and a workpiece. The improvement comprises in combination with the tungsten electrode, a starting laser focused upon the tungsten electrode which to ignite the electrode heats a spot on the energized electrode sufficient for formation of a thermionic arc. Interference problems associated with high frequency starters are thus overcome. 3 figs.

  10. Metal halide arc discharge lamp having short arc length

    NASA Technical Reports Server (NTRS)

    Muzeroll, Martin E. (Inventor)

    1994-01-01

    A metal halide arc discharge lamp includes a sealed light-transmissive outer jacket, a light-transmissive shroud located within the outer jacket and an arc tube assembly located within the shroud. The arc tube assembly includes an arc tube, electrodes mounted within the arc tube and a fill material for supporting an arc discharge. The electrodes have a spacing such that an electric field in a range of about 60 to 95 volts per centimeter is established between the electrodes. The diameter of the arc tube and the spacing of the electrodes are selected to provide an arc having an arc diameter to arc length ratio in a range of about 1.6 to 1.8. The fill material includes mercury, sodium iodide, scandium tri-iodide and a rare gas, and may include lithium iodide. The lamp exhibits a high color rendering index, high lumen output and high color temperature.

  11. Acute and chronic toxic effects of chloramphenicol on Scenedesmus obliquus and Chlorella pyrenoidosa.

    PubMed

    Zhang, Wei; Sun, Wenfang; An, Shuai; Xiong, Bang; Lin, Kuangfei; Cui, Xinhong; Guo, Meijin

    2013-08-01

    The acute and chronic toxicological effects of Chloramphenicol (CAP) on Scenedesmus obliquus and Chlorella pyrenoidosa are not well understood. The indoor experiments were carried to observe and analyze the CAP induced changes. Results of the observations have showed that CAP exposure could significantly inhibit the growth of Scenedesmus obliquus in almost all the treated groups, while Chlorella pyrenoidosa exhibited less sensitivity. Chlorophyll-a syntheses of Scenedesmus obliquus were all inhibited by CAP exposure, while Chlorella pyrenoidosa displayed obvious stimulation effect. Catalase (CAT) and Superoxide dismutase (SOD) activities of both algae were promoted in all the treatments. The experimental results indicated that the growth and Chlorophyll-a syntheses of Scenedesmus obliquus were more sensitive in response to CAP exposure than that of Chlorella pyrenoidosa. While for CAT and SOD activities, Chlorella pyrenoidosa showed more susceptible. This research provides a basic understanding of CAP toxicity to aquatic organisms.

  12. Arc Voltage Between Deion Grid Affected by Division of Arc in Magnetic Driven Arc

    NASA Astrophysics Data System (ADS)

    Inuzuka, Yutaro; Yamato, Takashi; Yamamoto, Shinji; Iwao, Toru

    2016-10-01

    Magnetic driven arc has been applied to DC breaker and fault current limiters. However, it has not been researched, especially stagnation and re-strike of the arc. In this paper, the arc voltage between deion grid affected by division of arc in magnetic driven arc and arc behavior are measured by using the oscilloscope and HSVC (High Speed Video Camera). As a result, arc voltage increased because of division of the arc. The arc mean moving speed increases with increasing the external magnetic field. However, when the arc was not stalemate, the arc moving speed does not change so much. The arc re-strike time increases and stalemate time decreases with increasing the external magnetic field. Therefore, the anode spot moving speed increases 8 times because arc re-strike occurs easily with the external magnetic field. Thus, the erosion of electrodes decreases and the arc movement becomes the smooth. When the arc is divided, the arc voltage increased because of the electrode fall voltage. Therefore, the arc voltage increases with increasing the number of deion grid.

  13. Filtered cathodic arc source

    DOEpatents

    Falabella, S.; Sanders, D.M.

    1994-01-18

    A continuous, cathodic arc ion source coupled to a macro-particle filter capable of separation or elimination of macro-particles from the ion flux produced by cathodic arc discharge is described. The ion source employs an axial magnetic field on a cathode (target) having tapered sides to confine the arc, thereby providing high target material utilization. A bent magnetic field is used to guide the metal ions from the target to the part to be coated. The macro-particle filter consists of two straight solenoids, end to end, but placed at 45[degree] to one another, which prevents line-of-sight from the arc spot on the target to the parts to be coated, yet provides a path for ions and electrons to flow, and includes a series of baffles for trapping the macro-particles. 3 figures.

  14. Filtered cathodic arc source

    DOEpatents

    Falabella, Steven; Sanders, David M.

    1994-01-01

    A continuous, cathodic arc ion source coupled to a macro-particle filter capable of separation or elimination of macro-particles from the ion flux produced by cathodic arc discharge. The ion source employs an axial magnetic field on a cathode (target) having tapered sides to confine the arc, thereby providing high target material utilization. A bent magnetic field is used to guide the metal ions from the target to the part to be coated. The macro-particle filter consists of two straight solenoids, end to end, but placed at 45.degree. to one another, which prevents line-of-sight from the arc spot on the target to the parts to be coated, yet provides a path for ions and electrons to flow, and includes a series of baffles for trapping the macro-particles.

  15. Electric arc saw apparatus

    DOEpatents

    Deichelbohrer, P.R.

    1983-08-08

    A portable, hand-held electric arc saw apparatus comprising a small frame for supporting an electrically conducting rotary blade which serves as an electrode for generating an electric arc between the blade and a workpiece of opposite polarity. Electrically conducting means are provided on said frame for transmitting current to said blade. A pair of freely movable endless belts in the form of crawler treads are employed to facilitate movement of the apparatus relative to the workpiece.

  16. Diagnosis and clinical features of pemphigus vulgaris.

    PubMed

    Venugopal, Supriya S; Murrell, Dédée F

    2012-05-01

    Autoimmune bullous diseases are associated with autoimmunity against structural components that maintain cell-cell and cell-matrix adhesion in the skin and mucous membranes. They include those where the skin blisters at the basement membrane zone and those where the skin blisters within the epidermis (pemphigus vulgaris, pemphigus foliaceus, and other subtypes of pemphigus). The variants of pemphigus are determined according to the level of intraepidermal split formation. There are 5 main variants of pemphigus: pemphigus vulgaris, pemphigus foliaceus, pemphigus erythematosus, drug-induced pemphigus, and paraneoplastic pemphigus. This review focuses only on pemphigus vulgaris.

  17. Diagnosis and clinical features of pemphigus vulgaris.

    PubMed

    Venugopal, Supriya S; Murrell, Dédée F

    2011-07-01

    Autoimmune bullous diseases are associated with autoimmunity against structural components that maintain cell-cell and cell-matrix adhesion in the skin and mucous membranes. They include those where the skin blisters at the basement membrane zone and those where the skin blisters within the epidermis (pemphigus vulgaris, pemphigus foliaceus, and other subtypes of pemphigus). The variants of pemphigus are determined according to the level of intraepidermal split formation. There are 5 main variants of pemphigus: pemphigus vulgaris, pemphigus foliaceus, pemphigus erythematosus, drug-induced pemphigus, and paraneoplastic pemphigus. This review focuses only on pemphigus vulgaris.

  18. Hypertrophic lupus vulgaris: an unusual presentation.

    PubMed

    Jain, Vijay K; Aggarwal, Kamal; Jain, Sarika; Singh, Sunita

    2009-07-01

    Lupus vulgaris is the most common form of cutaneous tuberculosis occurring in previously sensitized individuals with a high degree of tuberculin sensitivity. Various forms including plaque, ulcerative, hypertrophic, vegetative, papular, and nodular forms have been described. A 30-year-old male patient presented with a very large hypertrophic lupus vulgaris lesion over left side of chest since 22 years. Histopathological examination showed granulomatous infiltration without caseation necrosis. The Mantoux reaction was strongly positive. Hypertrophic lupus vulgaris of such a giant size and that too at an unusual site is extremely rare and hence is being reported.

  19. Interaction of organic solvents with the green alga Chlorella pyrenoidosa

    SciTech Connect

    Stratton, G.W.; Smith, T.M. )

    1988-06-01

    Solvents are often a component of bioassay systems when water-insoluble toxicants are being tested. These solvents must also be considered as xenobiotics and therefore, as potential toxicants in the bioassay. However, the effects of solvents on the organisms being tested and their possible interaction with the test compound are often overlooked by researchers. The purpose of the present study was to compare the inhibitory effects of six solvents commonly used in pesticide bioassays towards growth of the common green alga Chlorella pyrenoidosa, and to examine the occurrence of solvent-pesticide interactions with this organism.

  20. Characterization and Quantitation of Vitamin B12 Compounds in Various Chlorella Supplements.

    PubMed

    Bito, Tomohiro; Bito, Mariko; Asai, Yusuke; Takenaka, Shigeo; Yabuta, Yukinori; Tago, Kazunori; Ohnishi, Masato; Mizoguchi, Toru; Watanabe, Fumio

    2016-11-16

    Vitamin B12 was determined and characterized in 19 dried Chlorella health supplements. Vitamin contents of dried Chlorella cells varied from <0.1 μg to approximately 415 μg per 100 g of dry weight. Subsequent liquid chromatography/electrospray ionization-tandem mass spectrometry analyses showed the presence of inactive corrinoid compounds, a cobalt-free corrinoid, and 5-methoxybenzimidazolyl cyanocobamide (factor IIIm) in four and three high vitamin B12-containing Chlorella tablets, respectively. In four Chlorella tablet types with high and moderate vitamin B12 contents, the coenzyme forms of vitamin B12 5'-deoxyadenosylcobalamin (approximately 32%) and methylcobalamin (approximately 8%) were considerably present, whereas the unnaturally occurring corrinoid cyanocobalamin was present at the lowest concentrations. The species Chlorella sorokiniana (formerly Chlorella pyrenoidosa) is commonly used in dietary supplements and did not show an absolute requirement of vitamin B12 for growth despite vitamin B12 uptake from the medium being observed. In further experiments, vitamin B12-dependent methylmalonyl-CoA mutase and methionine synthase activities were detected in cell homogenates. In particular, methionine synthase activity was significantly increased following the addition of vitamin B12 to the medium. These results suggest that vitamin B12 contents of Chlorella tablets reflect the presence of vitamin B12-generating organic ingredients in the medium or the concomitant growth of vitamin B12-synthesizing bacteria under open culture conditions.

  1. Chlorella is an effective dietary source of lutein for human erythrocytes.

    PubMed

    Miyazawa, Taiki; Nakagawa, Kiyotaka; Kimura, Fumiko; Nakashima, Yuya; Maruyama, Isao; Higuchi, Ohki; Miyazawa, Teruo

    2013-01-01

    Chlorella contains a high amount of carotenoids, especially lutein, and has received attention as a possible dietary source for improving carotenoid levels in human blood. In the present study, we performed a 2-month single arm human study, and investigated the efficacy of Chlorella supplementation (9 g Chlorella/day; equivalent to 32 mg lutein/day) on lutein and other carotenoid concentrations in plasma as well as erythrocytes of 12 healthy subjects. Following Chlorella supplementation, lutein was the predominant carotenoid in erythrocytes, showing a 4-fold increase (from 14 to 54 pmol/mL packed cells). After the one month without Chlorella ingestion, erythrocyte lutein then decreased to a basal level (17 pmol/mL packed cells). Erythrocyte carotenoid (lutein, zeaxanthin, α-carotene, and β-carotene) levels were proportional to plasma carotenoid levels. The results suggest the transfer of Chlorella carotenoids, especially lutein, from plasma lipoprotein particles to the erythrocyte membrane. Chlorella intake would be effective for improving and maintaining lutein concentrations in human erythrocytes.

  2. Consolidating NASA's Arc Jets

    NASA Technical Reports Server (NTRS)

    Balboni, John A.; Gokcen, Tahir; Hui, Frank C. L.; Graube, Peter; Morrissey, Patricia; Lewis, Ronald

    2015-01-01

    The paper describes the consolidation of NASA's high powered arc-jet testing at a single location. The existing plasma arc-jet wind tunnels located at the Johnson Space Center were relocated to Ames Research Center while maintaining NASA's technical capability to ground-test thermal protection system materials under simulated atmospheric entry convective heating. The testing conditions at JSC were reproduced and successfully demonstrated at ARC through close collaboration between the two centers. New equipment was installed at Ames to provide test gases of pure nitrogen mixed with pure oxygen, and for future nitrogen-carbon dioxide mixtures. A new control system was custom designed, installed and tested. Tests demonstrated the capability of the 10 MW constricted-segmented arc heater at Ames meets the requirements of the major customer, NASA's Orion program. Solutions from an advanced computational fluid dynamics code were used to aid in characterizing the properties of the plasma stream and the surface environment on the calorimeters in the supersonic flow stream produced by the arc heater.

  3. [Culture medium based on biogas slurry and breeding of oil Chlorella].

    PubMed

    Zhao, Feng-Min; Mei, Shuai; Cao, You-Fu; Ding, Jin-Feng; Xu, Jia-Jie; Li, Shu-Jun

    2014-06-01

    The oil chlorella cultivation and biogas slurry treatment were combined. The biogas slurry provided water and nutrient for growing chlorella, at the same time, harmless treatment of biogas slurry was realized. This paper cultivated 4 species of oil chlorella in the mixed medium of biogas slurry and green algae medium (the volume ratios were 1 : 9, 1 : 3, 1 : 1 and 3 : 1, respectively), and compared their oil productivity to select the best oil chlorella species and the optimal culture medium. The results showed that, the combination of medium and chlorella species to reach the highest oil productivity was a volume ratio of 1 : 3 and the chlorella species BJ05, and the oil productivity of chlorella BJ05 was 9.20 mg x (L x d)(-1), higher than that in green algae medium [8.66 mg x (L x d)(-1)]. In mixed medium with a volume ratio of 1:3, the effect of adding different nutrients into the green algae medium on the oil productivity was examined, and the results showed that, sodium carbonate and citric acid had no negative effect on the oil productivity of chlorella BJ05. in the absence of sodium carbonate and citric acid, the oil productivity of chlorella BJ05 was 9.36 mg x (L x d)(-1), and the removal of COD (chemical oxygen demand), total nitrogen, total phosphorus and ammonia nitrogen rates were 59%, 75%, 61% and 100%, respectively. Deficiency in other nutrients had negative effect on the oil productivity. Therefore, the culture medium was further optimized to the mixed medium of biogas slurry and green algae medium with a volume ratio of 1 : 3 and without addition of sodium carbonate and citric acid.

  4. The inactivation of Chlorella spp. with dielectric barrier discharge in gas-liquid mixture

    NASA Astrophysics Data System (ADS)

    Song, Dan; Sun, Bing; Zhu, Xiaomei; Yan, Zhiyu; Liu, Hui; Liu, Yongjun

    2013-03-01

    The inactivation of Chlorella spp. with high voltage and frequency pulsed dielectric barrier discharge in hybrid gas-liquid reactor with a suspension electrode was studied experimentally. In the hybrid gas-liquid reactor, a steel plate was used as high voltage electrode while a quartz plate as a dielectric layer, another steel plate placing in the aqueous solution worked as a whole ground electrode. A suspension electrode is installed near the surface of solution between high voltage and ground electrode to make the dielectric barrier discharge uniform and stable, the discharge gap was between the quartz plate and the surface of the water. The effect of peak voltage, treatment time, the initial concentration of Chlorella spp. and conductivity of solution on the inactivation rate of Chlorella spp. was investigated, and the inactivation mechanism of Chlorella spp. preliminarily was studied. Utilizing this system inactivation of Chlorella spp., the inactivation rate increased with increasing of peak voltage, treatment time and electric conductivity. It was found that the inactivation rate of Chlorella spp. arrived at 100% when the initial concentration was 4 × 106 cells mL-1, and the optimum operation condition required a peak voltage of 20 kV, a treatment time of 10 min and a frequency of 7 kHz. Though the increasing of initial concentration of the Chlorella spp. contributed to the addition of interaction probability between the Chlorella spp. and O3, H2O2, high-energy electrons, UV radiation and other active substances, the total inactivation number raise, but the inactivation rate of the Chlorella spp. decreased.

  5. Control of arc length during gas metal arc welding

    SciTech Connect

    Madigan, R.B.; Quinn, T.P.

    1994-12-31

    An arc-length control system has been developed for gas metal arc welding (GMAW) under spray transfer welding conditions. The ability to monitor and control arc length during arc welding allows consistent weld characteristics to be maintained and therefore improves weld quality. Arc length control has only been implemented for gas tungsten arc welding (GTAW), where an automatic voltage control (AVC) unit adjusts torch-to-work distance. The system developed here compliments the voltage- and current-sensing techniques commonly used for control of GMAW. The system consists of an arc light intensity sensor (photodiode), a Hall-effect current sensor, a personal computer and software implementing a data interpretation and control algorithms. Arc length was measured using both arc light and arc current signals. Welding current was adjusted to maintain constant arc length. A proportional-integral-derivative (PID) controller was used. Gains were automatically selected based on the desired welding conditions. In performance evaluation welds, arc length varied from 2.5 to 6.5 mm while welding up a sloped workpiece (ramp in CTWD) without the control. Arc length was maintained within 1 mm of the desired (5 mm ) with the control.

  6. Phaseolus vulgaris endornavirus 1 and Phaseolus vulgaris endornavirus 2 infecting common bean Phaseolus vulgaris genotypes show differential infection patterns between gene pools

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We investigated the occurrence of two plant endornaviruses, Phaseolus vulgaris endornavirus 1 (PvEV-1) and Phaseolus vulgaris endornavirus 2 (PvEV-2), in breeding-lines, cultivars, landraces, and wild genotypes of common bean (Phaseolus vulgaris) as well as other Phaseolus species collected from two...

  7. Berberis Vulgaris and Berberine: An Update Review.

    PubMed

    Imenshahidi, Mohsen; Hosseinzadeh, Hossein

    2016-11-01

    Berberine is an isoquinoline alkaloid present in several plants, including Coptis sp. and Berberis sp. Berberine is a customary component in Chinese medicine, and is characterized by a diversity of pharmacological effects. An extensive search in electronic databases (PubMed, Scopus, Ovid, Wiley, ProQuest, ISI, and Science Direct) were used to identify the pharmacological and clinical studies on Berberis vulgaris and berberine, during 2008 to 2015, using 'berberine' and 'Berberis vulgaris' as search words. We found more than 1200 new article studying the properties and clinical uses of berberine and B. vulgaris, for treating tumor, diabetes, cardiovascular disease, hyperlipidemia, inflammation, bacterial and viral infections, cerebral ischemia trauma, mental disease, Alzheimer disease, osteoporosis, and so on. In this article, we have updated the pharmacological effects of B. vulgaris and its active constituent, berberine. Copyright © 2016 John Wiley & Sons, Ltd.

  8. [Childhood pemphigus vulgaris, a case report].

    PubMed

    Bellelli, Ana G; Mantero, Natalia M; Rueda, María L; Navacchia, Daniel; Cao, Gabriel; De Lillo, Leonardo; Grees, Susana A

    2016-12-01

    Pemphigus vulgaris is a chronic disease that is characterized by flaccid blisters and erosions, caused by immunoglobulin G autoantibodies against epidermal components. It is highly unusual in the pediatric population; it represents the 1.4 - 2.9% of the total cases. We present a case of pemphigus vulgaris in a 12 year old girl, which has implied a challenge both in its diagnosis and in its treatment.

  9. Diclofenac: a new trigger of pemphigus vulgaris?

    PubMed

    Matz, H; Bialy-Golan, A; Brenner, S

    1997-01-01

    Many drugs have been shown to induce pemphigus, including thiol and nonthiol drugs. We present a case of pemphigus vulgaris where a nonsteroidal anti-inflammatory medication, diclofenac in suppositories and topical gel preparations, is suspected of having triggered the disease. The temporal relationship between drug and outbreak of disease together with the positive migration inhibition factor test to diclofenac point to the possible involvement of this drug in triggering pemphigus vulgaris.

  10. Pemphigus vulgaris presenting with multiple lesion morphologies.

    PubMed

    Song, Philip In; Divito, Sherrie J; Kroshinsky, Daniela

    2014-12-14

    Pemphigus vulgaris is an uncommon intraepidermal blistering disorder that typically presents with flaccid bullae or erosions. We report a patient with pemphigus vulgaris who presented with several unusual clinical features: tense bullae with dependently layered pus, true target lesions coalescing into annular configurations, and diffuse desquamation that initially raised concern for toxic epidermal necrolysis. We discuss the differential diagnosis and implications of these morphological findings.

  11. Neonatal and infantile acne vulgaris: an update.

    PubMed

    Serna-Tamayo, Cristian; Janniger, Camila K; Micali, Giuseppe; Schwartz, Robert A

    2014-07-01

    Acne may present in neonates, infants, and small children. Neonatal and infantile acne vulgaris are not considered to be rare. The presentation of acne in this patient population sometimes represents virilization and may portend later development of severe adolescent acne. Neonatal and infantile acne vulgaris must be distinguished from other cutaneous disorders seen in newborns and infants. Infantile acne tends to be more pleomorphic and inflammatory, thus requiring more vigorous therapy than neonatal acne.

  12. Arc electrode interaction study

    NASA Technical Reports Server (NTRS)

    Zhou, X.; Berns, D.; Heberlein, J.

    1994-01-01

    The project consisted of two parts: (1) the cathode interaction studies which were a continuation of previous work and had the objective of increasing our understanding of the microscopic phenomena controlling cathode erosion in arc jet thrusters, and (2) the studies of the anode attachment in arc jet thrusters. The cathode interaction studies consisted of (1) a continuation of some modeling work in which the previously derived model for the cathode heating was applied to some specific gases and electrode materials, and (2) experimental work in which various diagnostics was applied to the cathode. The specific diagnostics used were observation of the cathode tip during arcing using a Laser Strobe Video system in conjunction with a tele-microscope, a monochromator with an optical multichannel analyzer for the determination of the cathode temperature distribution, and various ex situ materials analysis methods. The emphasis of our effort was shifted to the cathode materials analysis because a parallel project was in place during the second half of 1993 with a visiting scientist pursuing arc electrode materials studies. As a consequence, the diagnostic investigations of the arc in front of the cathode had to be postponed to the first half of 1994, and we are presently preparing these measurements. The results of last year's study showed some unexpected effects influencing the cathode erosion behavior, such as increased erosion away from the cathode tip, and our understanding of these effects should improve our ability to control cathode erosion. The arc jet anode attachment studies concentrated on diagnostics of the instabilities in subsonic anode attachment arc jet thrusters, and were supplemental measurements to work which was performed by one of the authors who spent the summer as an intern at NASA Lewis Research Center. A summary of the results obtained during the internship are included because they formed an integral part of the study. Two tasks for 1994, the

  13. Pulsed Long Arc Welding

    NASA Astrophysics Data System (ADS)

    Krampit, N. Yu

    2016-04-01

    The paper presents a method and an appliance for pulsed arc welding. The method supports dosage of energy required for melting each bead of electrode metal starting from the detachment of a bead. The appliance including a sensor to register bead detachment shows this moment due to the voltage burst in the arc space. Transferred beads of electrode metal are of similar size because of the dosage of energy used for melting each bead, as the consequence, the process is more stable and starting conditions to transfer electrode metal are similar, as the result, a produced weld is improved.

  14. Studies on uroporphyrinogen decarboxylase from Chlorella kessleri (Trebouxiophyceae, Chlorophyta).

    PubMed

    Juárez, Angela B; Aldonatti, Carmen; Vigna, María S; Ríos de Molina, María Del C

    2007-02-01

    Uroporphyrinogen decarboxylase (UroD) (EC 4.1.1.37) is an enzyme from the tetrapyrrole biosynthetic pathway, in which chlorophyll is the main final product in algae. This is the first time that a study on UroD activity has been performed in a green alga (Chlorella). We isolated and partially purified the enzyme from a Chlorella kessleri (Trebouxiophyceae, Chlorophyta) strain (Copahue, Neuquén, Argentina), and describe for the first time some of its properties. In C. kessleri, the decarboxylation of uroporphyrinogen III occurs in two stages, via 7 COOH and then 6 and 5 COOH intermediates, with the decarboxylation of the 7 COOH compound being the rate-limiting step for the reaction. Cultures in the exponential growth phase showed the highest specific activity values. The most suitable conditions to measure UroD activity in C. kessleri were as follows: 0.23-0.3 mg protein/mL, approximately 6-8 micromol/L uroporphyrinogen III, and 20 min incubation time. Gel filtration chromatography and Western blot assays indicated that UroD from C. kessleri is a dimer of approximately 90 kDa formed by species of lower molecular mass, which conserves enzymatic activity.

  15. Response of Desulfovibrio vulgaris to alkaline stress.

    PubMed

    Stolyar, Sergey; He, Qiang; Joachimiak, Marcin P; He, Zhili; Yang, Zamin Koo; Borglin, Sharon E; Joyner, Dominique C; Huang, Katherine; Alm, Eric; Hazen, Terry C; Zhou, Jizhong; Wall, Judy D; Arkin, Adam P; Stahl, David A

    2007-12-01

    The response of exponentially growing Desulfovibrio vulgaris Hildenborough to pH 10 stress was studied using oligonucleotide microarrays and a study set of mutants with genes suggested by microarray data to be involved in the alkaline stress response deleted. The data showed that the response of D. vulgaris to increased pH is generally similar to that of Escherichia coli but is apparently controlled by unique regulatory circuits since the alternative sigma factors (sigma S and sigma E) contributing to this stress response in E. coli appear to be absent in D. vulgaris. Genes previously reported to be up-regulated in E. coli were up-regulated in D. vulgaris; these genes included three ATPase genes and a tryptophan synthase gene. Transcription of chaperone and protease genes (encoding ATP-dependent Clp and La proteases and DnaK) was also elevated in D. vulgaris. As in E. coli, genes involved in flagellum synthesis were down-regulated. The transcriptional data also identified regulators, distinct from sigma S and sigma E, that are likely part of a D. vulgaris Hildenborough-specific stress response system. Characterization of a study set of mutants with genes implicated in alkaline stress response deleted confirmed that there was protective involvement of the sodium/proton antiporter NhaC-2, tryptophanase A, and two putative regulators/histidine kinases (DVU0331 and DVU2580).

  16. Response of Desulfovibrio vulgaris to Alkaline Stress

    SciTech Connect

    Stolyar, S.; He, Q.; He, Z.; Yang, Z.; Borglin, S.E.; Joyner, D.; Huang, K.; Alm, E.; Hazen, T.C.; Zhou, J.; Wall, J.D.; Arkin, A.P.; Stahl, D.A.

    2007-11-30

    The response of exponentially growing Desulfovibrio vulgarisHildenborough to pH 10 stress was studied using oligonucleotidemicroarrays and a study set of mutants with genes suggested by microarraydata to be involved in the alkaline stress response deleted. The datashowed that the response of D. vulgaris to increased pH is generallysimilar to that of Escherichia coli but is apparently controlled byunique regulatory circuits since the alternative sigma factors (sigma Sand sigma E) contributing to this stress response in E. coli appear to beabsent in D. vulgaris. Genes previously reported to be up-regulated in E.coli were up-regulated in D. vulgaris; these genes included three ATPasegenes and a tryptophan synthase gene. Transcription of chaperone andprotease genes (encoding ATP-dependent Clp and La proteases and DnaK) wasalso elevated in D. vulgaris. As in E. coli, genes involved in flagellumsynthesis were down-regulated. The transcriptional data also identifiedregulators, distinct from sigma S and sigma E, that are likely part of aD. vulgaris Hildenborough-specific stress response system.Characterization of a study set of mutants with genes implicated inalkaline stress response deleted confirmed that there was protectiveinvolvement of the sodium/proton antiporter NhaC-2, tryptophanase A, andtwo putative regulators/histidine kinases (DVU0331 andDVU2580).

  17. Nail involvement in pemphigus vulgaris.

    PubMed

    Engineer, L; Norton, L A; Ahmed, A R

    2000-09-01

    Nail involvement in pemphigus vulgaris is relatively rare. We describe a case of severe pemphigus involving both the skin and oral mucosa in which an acute exacerbation was preceded by the onset of nail involvement of all 4 extremities. Nail involvement occurred in the form of hemorrhagic paronychia of multiple digits. Oral, cutaneous, and nail manifestations of the disease were all well controlled by systemic therapy. A review of the literature on nail involvement in pemphigus reveals that this involvement may be manifested in multiple ways, with chronic paronychia and onychomadesis being the most common. Involvement of the nail occurs most frequently either as part of the initial presentation, or just before or concurrent with a flare of pre-existing disease. Nail involvement, when it occurs, is usually present when the disease is severe. Topical therapy is insufficient, and systemic therapy is warranted. In the majority of cases, nail recovery is complete, with no residual damage.

  18. Pemphigus vulgaris affecting 19 nails.

    PubMed

    Patsatsi, A; Sotiriou, E; Devliotou-Panagiotidou, D; Sotiriadis, D

    2009-03-01

    A 60-year-old woman presented with painful erosions in the oral mucosa, pharynx, perineum and perianal area, and multiple plaques with thick adherent crusts on the scalp. Most (nine) of the patient's fingernails had alterations in colour, affecting more than half of the nail plate, and all the toenails had severe inflammation of the nail folds, haemorrhagic paronychia and subungual or intraungual haemorrhage. A diagnosis of pemphigus vulgaris (PV) was made based on histology and on direct and indirect immunofluorescence findings. Groups of acantholytic cells were also observed in a Tzanck smear obtained from a subungual lesion. Onychomadesis in most of the fingernails and in all the toenails developed gradually. The patient was hospitalized and treated with oral corticosteroids. Complete recovery without residual damage to the nails and persistent remission was achieved. Nail involvement in PV is rarely described and is always of interest, as its presentation varies widely.

  19. Pemphigus vulgaris: approach to treatment.

    PubMed

    Sinha, Animesh A; Hoffman, Melissa B; Janicke, Elise C

    2015-04-01

    The therapeutic management of pemphigus vulgaris (PV) is centered around immunosuppression, which can be generalized, as in the use of corticosteroids or steroid sparing agents, or specific, as in therapeutic blockage of autoantibody production, certain cytokines, or signaling pathways. Currently, the backbone of treatment for PV, particularly, first line therapy, remains systemic corticosteroids. Although very effective, the significant side effects of long-term corticosteroid usage are well documented. Adjunctive therapies aim to eliminate, or at least decrease, the necessary dose of corticosteroids. Specifically, azathioprine, cyclophosphamide, methotrexate, cyclosporine, mycophenolate mofetil and dapsone are now widely used in PV. Intravenous immunoglobulin (IVIG), plasmapheresis, immunoadsorption, and most recently, rituximab, are other members of the therapeutic armamentarium. However, despite the widening range of treatment options in PV, well-controlled clinical trials and consensus guidelines are lacking.

  20. Removal of Nitrogen and Phosphorus From Reject Water Using Chlorella vulgaris Algae After Partial Nitrification/Anammox Process.

    PubMed

    Gutwinski, Piotr; Cema, Grzegorz

    2016-01-01

    Wastewater containing nutrients like ammonia, nitrite, nitrate and phosphates have been identified as the main cause of eutrophication in natural waters. Therefore, a suitable treatment is needed. In classical biological processes, nitrogen and phosphorus removal is expensive, especially due to the lack of biodegradable carbon, thus new methods are investigated. In this paper, the new possibility of nitrogen and phosphorus removal in side stream after the partial nitrification/Anammox process is proposed. Research was carried out in a lab-scale vertical tubular photobioreactor (VTR) fed with real reject water, from dewatering of digested sludge, after partial nitrification/Anammox process from lab-scale sequencing batch reactor (SBR). Nitrogen and phosphorus concentrations were measured every three days. The average nitrogen and phosphorus loads were 0.0503 ± 0.036 g N g(vss)/d and 0.0389 ± 0.013 g P g(vss)/d accordingly. Results have shown that microalgae were able to efficiently remove nitrogen and phosphorus. The average nitrogen removal was 36.46% and phosphorus removal efficiency varied between 93 and 100%.

  1. BEHAVIORAL AND PHYSIOLOGICAL RESPONSES OF DAPHNIA MAGNA, CHLORELLA VULGARIS, CORBICULA FLUMINEA, AND LEPOMIS MACROCHIRUS TO COPPER AND CYANIDE

    EPA Science Inventory

    The research presented here was designed to further the science of available and developing continuous, automated water quality monitors and how they may be most effectively deployed in a watershed management plan and/or water quality early warning system (WQEWS). Source waters ...

  2. Acute and chronic toxicity of emerging contaminants, alone or in combination, in Chlorella vulgaris and Daphnia magna.

    PubMed

    Pablos, María Victoria; García-Hortigüela, Pilar; Fernández, Carlos

    2015-04-01

    This work presents the toxicity results of different compounds classified as emerging contaminants on primary producers and primary consumers in the aquatic compartment. The objectives were to (1) obtain acute and chronic toxicity results for algae and Daphnia magna using standardised or currently used tests, (2) study the relationship between the effects on the impaired feeding rate for daphnia and the effects of reproduction and (3) examine the responses on daphnia and algae after binary combinations of environmentally relevant compounds and perfluorooctane sulfonate (PFOS). Toxicity data on personal care products (PCPs), not reported in the scientific literature up to now, are presented. The results confirmed that the Daphnia feeding bioassay can be a sensitive, ecologically relevant endpoint to detect sublethal effects and could complement the information obtained with the reproduction test on Daphnia. The results also suggested that the concomitant occurrence of PFOS and other emerging contaminants in the aquatic compartment could affect the toxicity of some compounds according to their lipophilicity.

  3. Evaluation of the toxicity of ZnO nanoparticles to Chlorella vulgaris by use of the chiral perturbation approach.

    PubMed

    Zhou, Hui; Wang, Xiaojun; Zhou, Ying; Yao, Hongzhou; Ahmad, Farooq

    2014-06-01

    The toxicity of ZnO nanoparticles (NPs) has been widely investigated because of their extensive use in consumer products. The mechanism of the toxicity of ZnO NPs to algae is unclear, however, and it is difficult to differentiate between particle-induced toxicity and the effect of dissolved Zn(2+). In the work discussed in this paper we investigated particle-induced toxicity and the effects of dissolved Zn(2+) by using the chiral perturbation approach with dichlorprop (DCPP) as chiral perturbation factor. The results indicated that intracellular zinc is important in the toxicity of ZnO NPs, and that ZnO NPs cause oxidative damage. According to dose-response curves for DCPP and the combination of ZnO NPs with (R)-DCPP or (S)-DCPP, the toxicity of DCPP was too low to perturb the toxicity of ZnO NPs, so DCPP was suitable for use as chiral perturbation factor. The different glutathione (GSH) content of algal cells exposed to (R)-DCPP or (S)-DCPP correlated well with different production of reactive oxygen species (ROS) after exposure to the two enantiomers. Treatment of algae with ZnO NPs and (R)-DCPP resulted in reduced levels of GSH and the glutathione/oxidized glutathione (GSH/GSSG) ratio in the cells compared with the control. Treatment of algae with ZnO NPs and (S)-DCPP, however, resulted in no significant changes in GSH and GSH/GSSG. Moreover, trends of variation of GSH and GSH/GSSG were different when algae were treated with ZnSO4·7H2O and the two enantiomers. Overall, the chiral perturbation approach revealed that NPs aggravated generation of ROS and that released Zn(2+) and NPs both contribute to the toxicity of ZnO NPs.

  4. Mapping the fundamental niches of two freshwater microalgae, Chlorella vulgaris (Trebouxiophyceae) and Peridinium cinctum (Dinophyceae), in 5-dimensional ion space

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A five dimensional experimental design, i.e. a five component ion mixture design for nitrate, phosphate, potassium, sodium and chloride projected across a total ion concentration gradient of 1-30 mM was utilized to map the ion-based, scenopoetic, or ‘Grinnellian’, niche space for two freshwater alga...

  5. ARc Welding (Industrial Processing Series).

    DTIC Science & Technology

    ARC WELDING , *BIBLIOGRAPHIES), (*ARC WELDS, BIBLIOGRAPHIES), ALUMINUM ALLOYS, TITANIUM ALLOYS, CHROMIUM ALLOYS, METAL PLATES, SPOT WELDING , STEEL...INERT GAS WELDING , MARAGING STEELS, MICROSTRUCTURE, HEAT RESISTANT ALLOYS, HEAT RESISTANT METALS, WELDABILITY, MECHANICAL PROPERTIES, MOLYBDENUM ALLOYS, NICKEL ALLOYS, RESISTANCE WELDING

  6. Thermal Arc Spray Overview

    NASA Astrophysics Data System (ADS)

    Hafiz Abd Malek, Muhamad; Hayati Saad, Nor; Kiyai Abas, Sunhaji; Mohd Shah, Noriyati

    2013-06-01

    Usage of protective coating for corrosion protection was on highly demand during the past decade; and thermal spray coating played a major part during that time. In recent years, the thermal arc spray coating becomes a popular coating. Many big players in oil and gas such as PETRONAS, EXXON MOBIL and SHELL in Malaysia tend to use the coating on steel structure as a corrosion protection. Further developments in coating processes, the devices, and raw materials have led to expansion of functional coatings and applications scope from conventional coating to specialized industries. It is widely used because of its ability to withstand high process temperature, offer advantages in efficiency, lower cost and acts as a corrosion protection. Previous research also indicated that the thermal arc spray offers better coating properties compared to other methods of spray. This paper reviews some critical area of thermal spray coating by discussing the process/parameter of thermal arc spray technology and quality control of coating. Coating performance against corrosion, wear and special characteristic of coating are also described. The field application of arc spray technology are demonstrated and reviewed.

  7. Variable polarity arc welding

    NASA Technical Reports Server (NTRS)

    Bayless, E. O., Jr.

    1991-01-01

    Technological advances generate within themselves dissatisfactions that lead to further advances in a process. A series of advances in welding technology which culminated in the Variable Polarity Plasma Arc (VPPA) Welding Process and an advance instituted to overcome the latest dissatisfactions with the process: automated VPPA welding are described briefly.

  8. Gas tungsten arc welder

    DOEpatents

    Christiansen, D.W.; Brown, W.F.

    A welder for automated closure of fuel pins by a gas tungsten arc process in which a rotating length of cladding is positioned adjacent a welding electrode in a sealed enclosure. An independently movable axial grinder is provided in the enclosure for refurbishing the used electrode between welds.

  9. Arc Length Gone Global

    ERIC Educational Resources Information Center

    Boudreaux, Gregory M.; Wells, M. Scott

    2007-01-01

    Everyone with a thorough knowledge of single variable calculus knows that integration can be used to find the length of a curve on a given interval, called its arc length. Fortunately, if one endeavors to pose and solve more interesting problems than simply computing lengths of various curves, there are techniques available that do not require an…

  10. Ionic liquids-based hydrolysis of Chlorella biomass for fermentable sugars.

    PubMed

    Zhou, Na; Zhang, Yimin; Gong, Xiaowu; Wang, Qinhong; Ma, Yanhe

    2012-08-01

    An ionic liquids-based chemical hydrolysis strategy was developed to obtain high-yielding soluble sugars from Chlorella biomass. Initial ionic liquids dissolution and subsequently HCl catalyzed hydrolysis could dissolve 75.34% of Chlorella biomass and release 88.02% of total sugars from Chlorella biomass. The amount of HCl loading was 7 wt.% relative to Chlorella biomass weight, which was much lower (only 14.6%) than that in HCl/MgCl(2)-catalyzed system with similar sugars release (Zhou et al., 2011). Ionic liquids in the hydrolysates were recycled and fermentable sugars were evaluated by converting to bioethanol after separated by ion-exclusion chromatography. This ionic liquids-based hydrolysis strategy showed the great potential to produce fermentable sugars from algal biomass.

  11. Aluminum bioavailability to the green alga Chlorella pyrenoidosa in acidified synthetic soft water

    SciTech Connect

    Parent, L.; Campbell, P.G.C. )

    1994-04-01

    A unicellular green alga, Chlorella pyrenoidosa, was exposed to inorganic Al under controlled experimental conditions to determine whether the biological response elicited by the dissolved metal could be predicted from the free-metal ion concentration, [Al[sup 3+

  12. Cultivation of Chlorella sp. with livestock waste compost for lipid production.

    PubMed

    Zhu, L-D; Li, Z-H; Guo, D-B; Huang, F; Nugroho, Y; Xia, K

    2017-01-01

    Cultivation of microalgae Chlorella sp. with livestock waste compost as an alternative nutrient source was investigated in this present study. Five culture media with different nutrient concentrations were prepared. The characteristics of algal growth and lipid production were examined. The results showed that the specific growth rate together with biomass and lipid productivities was different among all the cultures. As the initial nutrient concentration decreased, the lipid content of Chlorella sp. increased. The variations in lipid productivity of Chlorella sp. among all the cultures were mainly due to the deviations in biomass productivity. The livestock waste compost medium with 2000mgL(-1)COD provided an optimal nutrient concentration for Chlorella sp. cultivation, where the highest productivities of biomass (288.84mgL(-1)day(-1)) and lipid (104.89mgL(-1)day(-1)) were presented.

  13. Evidence for a plasma-membrane-bound nitrate reductase involved in nitrate uptake of Chlorella sorokiniana

    NASA Technical Reports Server (NTRS)

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

    1989-01-01

    Anti-nitrate-reductase (NR) immunoglobulin-G (IgG) fragments inhibited nitrate uptake into Chlorella cells but had no affect on nitrate uptake. Intact anti-NR serum and preimmune IgG fragments had no affect on nitrate uptake. Membrane-associated NR was detected in plasma-membrane (PM) fractions isolated by aqueous two-phase partitioning. The PM-associated NR was not removed by sonicating PM vesicles in 500 mM NaCl and 1 mM ethylenediaminetetraacetic acid and represented up to 0.8% of the total Chlorella NR activity. The PM NR was solubilized by Triton X-100 and inactivated by Chlorella NR antiserum. Plasma-membrane NR was present in ammonium-grown Chlorella cells that completely lacked soluble NR activity. The subunit sizes of the PM and soluble NRs were 60 and 95 kDa, respectively, as determined by sodium-dodecyl-sulfate electrophoresis and western blotting.

  14. Hyaluronan synthesis in virus PBCV-1-infected chlorella-like green algae.

    PubMed

    Graves, M V; Burbank, D E; Roth, R; Heuser, J; DeAngelis, P L; Van Etten, J L

    1999-04-25

    We previously reported that the chlorella virus PBCV-1 genome encodes an authentic, membrane-associated glycosyltransferase, hyaluronan synthase (HAS). Hyaluronan, a linear polysaccharide chain composed of alternating beta1,4-glucuronic acid and beta1, 3-N-acetylglucosamine groups, is present in vertebrates as well as a few pathogenic bacteria. Studies of infected cells show that the transcription of the PBCV-1 has gene begins within 10 min of virus infection and ends at 60-90 min postinfection. The hyaluronan polysaccharide begins to accumulate as hyaluronan-lyase sensitive, hair-like fibers on the outside of the chlorella cell wall by 15-30 min postinfection; by 240 min postinfection, the infected cells are coated with a dense fibrous network. This hyaluronan slightly reduces attachment of a second chlorella virus to the infected algae. An analysis of 41 additional chlorella viruses indicates that many, but not all, produce hyaluronan during infection.

  15. Heme inhibition of [delta]-aminolevulinic acid synthesis is enhanced by glutathione in cell-free extracts of Chlorella

    SciTech Connect

    Weinstein, J.D.; Howell, R.W.; Grooms, S.Y.; Brignola, P.S. ); Mayer, S.M.; Beale, S.I. )

    1993-02-01

    In plants, algae, and many bacteria, the heme and chlorophyll precursor, [delta]-aminolevulinic acid (ALA), is synthesized from glutamate in a reaction involving a glutamyl-tRNA intermediate and requiring ATP and NADAPH as cofactors. In particulate-free extracts of algae and chloroplasts, ALA synthesis is inhibited by heme. Inclusion of 1.0 mM glutathione (GSH) in an enzyme and tRNA extract, derived from the green alga Chlorella vulgaris, lowered the concentration of heme required for 50% inhibition approximately 10-fold. The effect of GSH could not be duplicated with other reduced sulfhydryl compounds, including mercaptoethanol, dithiothreitol, and cysteine, or with imidazole or bovine serum albumin, which bind to heme and dissociate heme dimers. Absorption spectroscopy indicated that heme was fully reduced in incubation medium containing dithiothreitol, and addition of GSH did not alter the heme reduction state. Oxidized GSH was as effective in enhancing heme inhibition as the reduced form. Co-protoporphyrin IX inhibited ALA synthesis nearly as effectively as heme, and 1.0 mM GSH lowered the concentration required for 50% inhibition approximately 10-fold. Because GSH did not influence the reduction state of heme in the incubation medium, and because GSH could not be replaced by other reduced sulfhydryl compounds or ascorbate, the effect of GSH cannot be explained by action as a sulfhydryl protectant or heme reductant. Preincubation of enzyme extract with GSH, followed by rapid gel filtration, could not substitute for inclusion of GSH with heme during the reaction. The results suggest that GSH with heme during the reaction. The results suggest that GSH must specifically interact with the enzyme extract in the presence of the inhibitor to enhance the inhibition. 48 refs., 7 figs., 4 tabs.

  16. Optical Manipulation of Symbiotic Chlorella in Paramecium Bursaria Using a Fiber Axicon Microlens

    NASA Astrophysics Data System (ADS)

    Taguchi, K.; Hirota, S.; Nakayama, H.; Kunugihara, D.; Mihara, Y.

    2012-03-01

    In this paper, chemically etched axicon fiber was proposed for laser trapping of symbiotic chlorella from paramecium bursaria. We fabricated axicon micro lenses on a single-mode bare optical fiber by selective chemical etching technique. The laser beam from fiber axicon microlens was strongly focused and optical forces were sufficient to move a symbiotic chlorella. From experimental results, it was found that our proposed fiber axicon microlens was a promising tool for cell trapping without physical contact.

  17. Bioinspired, cytocompatible mineralization of silica-titania composites: thermoprotective nanoshell formation for individual chlorella cells.

    PubMed

    Ko, Eun Hyea; Yoon, Yeonjung; Park, Ji Hun; Yang, Sung Ho; Hong, Daewha; Lee, Kyung-Bok; Shon, Hyun Kyong; Lee, Tae Geol; Choi, Insung S

    2013-11-18

    Hard-shell case: Using a (RKK)4 D8 peptide allows mineralization to occur under cytocompatible conditions. Thus individual Chlorella cells could be encapsulated within a SiO2 -TiO2 nanoshell with high cell viability (87 %). The encapsulated Chlorella showed an almost threefold increase in their thermo-tolerance after 2 h at 45 °C.

  18. Chlorella-derived multicomponent supplementation increases aerobic endurance capacity in young individuals

    PubMed Central

    Umemoto, Sachiro; Otsuki, Takeshi

    2014-01-01

    Chlorella, a unicellular green alga, contains a variety of nutrients including amino acids, carbohydrates, vitamins, and minerals. A previous animal study found that maximal swimming time in mice increased after 14 days on a diet including Chlorella powder compared to no change in swimming performance on a normal diet. However, it is currently unknown whether Chlorella-derived multicomponent supplementation increases aerobic endurance capacity in humans. We investigated the effects of Chlorella-derived supplementation on peak oxygen uptake during incremental maximal cycling in young individuals using a double-blinded, placebo-controlled, crossover study design. Seven men and three women (mean age, 21.3 year) were allocated to placebo or Chlorella tablets (15 tablets × twice per day) for 4 weeks, with at least a 6-week washout period between trials, in a randomized order. Peak oxygen uptake significantly increased after Chlorella supplementation (before vs after, 37.9 ± 1.9 vs 41.4 ± 1.9 ml/kg/min, p = 0.003), but not with placebo (39.4 ± 2.2 vs 40.1 ± 2.1 ml/kg/min, p = 0.38). The change in peak oxygen uptake over the 4-week trial was significantly greater in the Chlorella trial than in the placebo trial (3.5 ± 0.9 vs 0.7 ± 0.8 ml/kg/min, p = 0.03). These results suggest that Chlorella-derived multicomponent supplementation increases aerobic endurance capacity in young individuals. PMID:25320462

  19. Lupus vulgaris: report of two cases.

    PubMed

    Wozniacka, Anna; Schwartz, Robert A; Sysa-Jedrzejowska, Anna; Borun, Marta; Arkuszewska, Cecylia

    2005-04-01

    Although there has been a steady decline in the incidence of tuberculosis in recent years, it persists in some regions, and where AIDS is especially prevalent, the number of new cases has been increasing. Thus, cutaneous tuberculosis has re-emerged in areas with a high incidence of HIV infection and multidrug-resistant pulmonary tuberculosis. Lupus vulgaris has been and remains the most common form of cutaneous tuberculosis. Cutaneous manifestations of disseminated tuberculosis are unusual, being seen in less than 0.5% of cases. Scrofuloderma, tuberculosis verrucosa cutis and lupus vulgaris comprise most cutaneous tuberculosis cases. Bacillus Calmette-Guerin (BCG) is derived from an attenuated strain of Mycobacterium bovis and is employed beneficially as a relatively safe vaccination in Poland and other countries in which the prevalence of tuberculosis is high. However, BCG vaccination may produce complications, including disseminated BCG and lupus vulgaris, the latter seen in one of our two patients in whom lupus vulgaris at the inoculation site followed a second vaccination with BCG 12 years after the initial one. A similar phenomenon has been described after immunotherapy with BCG vaccination. Re-infection (secondary) inoculation cutaneous tuberculosis may also occur as a result of BCG vaccination, producing either lupus vulgaris or tuberculosis verrucosa cutis, probably depending upon the patient's degree of cell-mediated immunity. However, most lupus vulgaris cases are not associated with vaccination with BCG, as occurred in our first patient. For those who do develop lupus vulgaris, it can be persistent for a long period, in some cases for many decades. In the second patient we describe a lengthy duration and cutaneous reactivation at distant sites after more than 40 years.

  20. Effect of maternal Chlorella supplementation on carotenoid concentration in breast milk at early lactation.

    PubMed

    Nagayama, Junya; Noda, Kiyoshi; Uchikawa, Takuya; Maruyama, Isao; Shimomura, Hiroshi; Miyahara, Michiyoshi

    2014-08-01

    Breast milk carotenoids provide neonates with a source of vitamin A and potentially, oxidative stress protection and other health benefits. Chlorella, which has high levels of carotenoids such as lutein, zeaxanthin and β-carotene, is an effective dietary source of carotenoids for humans. In this study, the effect of maternal supplementation with Chlorella on carotenoid levels in breast milk at early lactation was investigated. Ten healthy, pregnant women received 6 g of Chlorella daily from gestational week 16-20 until the day of delivery (Chlorella group); ten others did not (control group). Among the carotenoids detected in breast milk, lutein, zeaxanthin and β-carotene concentrations in the Chlorella group were 2.6-fold (p = 0.001), 2.7-fold (p = 0.001) and 1.7-fold (p = 0.049) higher, respectively, than those in the control group. Our study shows that Chlorella intake during pregnancy is effective in improving the carotenoid status of breast milk at early lactation.

  1. Chlorella starch branching enzyme II (BEII) can complement the function of BEIIb in rice endosperm.

    PubMed

    Sawada, Takayuki; Francisco, Perigio B; Aihara, Satomi; Utsumi, Yoshinori; Yoshida, Mayumi; Oyama, Yasunori; Tsuzuki, Mikio; Satoh, Hikaru; Nakamura, Yasunori

    2009-06-01

    In monocots, starch branching enzyme II (BEII) was functionally differentiated into BEIIa and BEIIb after separation from the dicots, and in cereals BEIIb plays a distinct role in amylopectin biosynthesis in the endosperm. The present study was conducted to examine to what extent a green algal BEII has an overlapping function with BEIIb in starch biosynthesis by introducing the Chlorella BEII gene into an amylose-extender (ae) mutant of rice. Chlorella BEII was found to complement the contribution of the rice endosperm BEIIb to the structures of amylopectin and starch granules because these mutated phenotypes were recovered almost completely to those of the wild type by the expression of Chlorella BEII. When the recombinant BE enzymes were incubated with the rice ae amylopectin, the branching pattern of Chlorella BEII was much more similar to that of rice BEIIb rather than rice BEIIa. Detailed analyses of BE reaction products suggests that BEIIb and Chlorella BEII only transfer chains with a degree of polymerization (DP) of 6 and 7, whereas BEIIa preferably transfers short chains with a DP of about 6-11. These results show that the Chlorella BEII is functionally similar to rice BEIIb rather than BEIIa.

  2. Hall-effect arc protector

    DOEpatents

    Rankin, Richard A.; Kotter, Dale K.

    1997-01-01

    The Hall-Effect Arc Protector is used to protect sensitive electronics from high energy arcs. The apparatus detects arcs by monitoring an electrical conductor, of the instrument, for changes in the electromagnetic field surrounding the conductor which would be indicative of a possible arcing condition. When the magnitude of the monitored electromagnetic field exceeds a predetermined threshold, the potential for an instrument damaging are exists and the control system logic activates a high speed circuit breaker. The activation of the breaker shunts the energy imparted to the input signal through a dummy load to the ground. After the arc condition is terminated, the normal signal path is restored.

  3. Hall-effect arc protector

    DOEpatents

    Rankin, R.A.; Kotter, D.K.

    1997-05-13

    The Hall-Effect Arc Protector is used to protect sensitive electronics from high energy arcs. The apparatus detects arcs by monitoring an electrical conductor, of the instrument, for changes in the electromagnetic field surrounding the conductor which would be indicative of a possible arcing condition. When the magnitude of the monitored electromagnetic field exceeds a predetermined threshold, the potential for an instrument damaging are exists and the control system logic activates a high speed circuit breaker. The activation of the breaker shunts the energy imparted to the input signal through a dummy load to the ground. After the arc condition is terminated, the normal signal path is restored. 2 figs.

  4. Sunflower Seed and Acne Vulgaris

    PubMed Central

    Mohebbipour, Alireza; Sadeghi-Bazargani, Homayoun; Mansouri, Mona

    2015-01-01

    Background: Regardless of the overall association between diet and acne which cannot be easily ignored, there might be an association between specific nutrients and acne development or improvement. Objectives: The aim of this study was to assess the effect of dietary intake of sunflower seeds on acne severity and the pattern of acne lesions. Patients and Methods: In a randomized controlled trial, 50 patients aged 15 - 30 years old with acne vulgaris were enrolled through consecutive convenient sampling, in a dermatology clinic in Ardabil, Iran. They were randomly allocated into two trial arms. Those in the control group were asked to stop eating sunflower seeds if they did before. In the intervention group, they consumed 25 g sunflower-containing food daily for seven days. The primary outcome of interest was 10% increase/decrease in the baseline acne severity index (ASI), sustained to the end of the follow-up period on day 14. Results: The mean ASI did not change significantly through the study period in the control group, but it increased in the sunflower group from 62 at the baseline to 86.8 after two weeks (P < 0.001). The ASI mean change was 24.8 in the sunflower group compared to 4.9 in the control group (P < 0.001). The global acne grading score (GAGS) did not significantly change in any of the groups and the difference in the change of GAGS was not significant between the groups (2.4 in the sunflower group versus 1.6 in the control group). Twenty two subjects (88%) in the sunflower group versus 9 (36%) in the control group had at least 10% increment in ASI throughout the follow-up period (P < 0.001). The relative risk of developing the primary outcome in taking the sunflower seed intervention was 2.4 (95% CI: 1.4 - 4.2). The observed risk difference was 0.52 (95% CI: 0.29 - 0.75). Conclusions: Sunflower seed intake appears to aggravate acne vulgaris; however, further evidence is needed to ban sunflower seed intake in patients with acne. Considering the

  5. Semicircular Rashba arc spin polarizer

    SciTech Connect

    Bin Siu, Zhuo; Jalil, Mansoor B. A.; Ghee Tan, Seng

    2014-05-07

    In this work, we study the generation of spin polarized currents using curved arcs of finite widths, in which the Rashba spin orbit interaction (RSOI) is present. Compared to the 1-dimensional RSOI arcs with zero widths studied previously, the finite width presents charge carriers with another degree of freedom along the transverse width of the arc, in addition to the longitudinal degree of freedom along the circumference of the arc. The asymmetry in the transverse direction due to the difference in the inner and outer radii of the arc breaks the antisymmetry of the longitudinal spin z current in a straight RSOI segment. This property can be exploited to generate spin z polarized current output from the RSOI arc by a spin unpolarized current input. The sign of the spin current can be manipulated by varying the arc dimensions.

  6. Disappearance of isocitrate lyase enzyme from cells of Chlorella pyrenoidosa

    PubMed Central

    John, P. C. L.; Thurston, C. F.; Syrett, P. J.

    1970-01-01

    1. When acetate-adapted cells of Chlorella are suspended in nitrogen-free medium and supplied with glucose, isocitrate lyase activity disappears from the cells at a rate of about 9%/h. This loss of activity is shown to be accompanied by loss of isocitrate lyase protein. 2. When isocitrate lyase activity is assayed in intact cells after freezing and thawing, the rate of loss of activity after addition of glucose approaches 20%/h. 3. It is shown, by using 35S, that the rate of turnover of isocitrate lyase protein is somewhat lower than that of other major soluble proteins; general protein turnover during nitrogen starvation, and after glucose addition, is too slow to account for the rate of loss of isocitrate lyase protein. 4. Disappearance of isocitrate lyase activity must result from a mechanism that allows degradation of this specific protein under conditions of limiting nitrogen supply. PMID:5492855

  7. Kinetics of phthalate ester biodegradation by Chlorella pyrenoidosa

    SciTech Connect

    Yan, H.; Ye, C.; Yin, C.

    1995-06-01

    Experimental results show that Chlorella pyrenoidosa has an ability to accumulate and biodegrade phthalate esters. Bioconcentration factors of dimethyl phthalate (DMP), diethyl phthalate (DEP), and dibutyl phthalate (DBP) reached their maxima of 162 at 24 h, 205 at 12 h, and 4,077 at 12 h. The average biodegradation rates of DMP, DEP, and DBP per day were found to be 13.4 mg/L, 7.3 mg/L, and 2.1 mg/L, respectively. Based on the experimental data, a second-order kinetic equation was formulated as {minus}dC/dt = KNr, with a factor r indicating the rate of algal growth. Calculation of this equation fits well with the observed data, and the standard deviations between calculated and observed values were 1.72 mg/L, 1.80 mg/L, and 0.26 mg/L for DMP, DEP, DBP, respectively.

  8. Thermo-chemical conversion of Chlorella pyrenoidosa to liquid biofuels.

    PubMed

    Duan, Peigao; Jin, Binbin; Xu, Yuping; Yang, Yan; Bai, Xiujun; Wang, Feng; Zhang, Lei; Miao, Jun

    2013-04-01

    The aim of the present study is to find how the solvent polarity affects the liquefaction behavior of Chlorella pyrenoidosa and subsequently using the most suitable solvent identified to explore the solvent/biomass ratio, time, and temperature on the products yield and properties of the bio-oil. The products yield was significantly affected by the solvent type, and ethanol was proven to be the most suitable solvent to convert C. pyrenoidosa into bio-oil from the yield and economic points of view. Temperature is the most influential factor on the products yield and properties of the bio-oil. The HHVs of the bio-oils produced under different reaction conditions are within the range of 27.68-36.45 MJ/kg. The major compounds in bio-oil were esters, fatty acids, alkenes, aldehydes, and amides, and fatty acid ethyl esters were the largest portion.

  9. HOLLOW CARBON ARC DISCHARGE

    DOEpatents

    Luce, J.S.

    1960-10-11

    A device is described for producing an energetic, direct current, hollow, carbon-arc discharge in an evacuated container and within a strong magnetic field. Such discharges are particularly useful not only in dissociation and ionization of high energy molecular ion beams, but also in acting as a shield or barrier against the instreaming of lowenergy neutral particles into a plasma formed within the hollow discharge when it is used as a dissociating mechanism for forming the plasma. There is maintained a predetermined ratio of gas particles to carbon particles released from the arc electrodes during operation of the discharge. The carbon particles absorb some of the gas particles and are pumped along and by the discharge out of the device, with the result that smaller diffusion pumps are required than would otherwise be necessary to dispose of the excess gas.

  10. Arc jet diagnostics tests

    NASA Technical Reports Server (NTRS)

    Willey, Ronald J.

    1989-01-01

    Two objectives were addressed during a 10 week 1988 NASA/ASEE summer faculty fellowship at the Johnson Space Center Atmospheric Reentry Materials Structures Evaluation Facility (ARMSEF). These objectives were the evaluation of mass spectrometry for the measurement of atomic and molecular species in an arc jet environment, and the determination of atomic recombination coefficients for reaction cured glass (RCG) coated high temperature surface insulation (HRSI) materials subjected to simulated reentry conditions. Evaluation of mass spectrometry for the measurement of atomic and molecular species provided some of the first measurements of point compositions in arc jet tunnel environments. A major objective of this project centered around the sampling residence time. A three staged vacuum sampling system pulled the molecules and atoms from the arc jet to a quadrupole ionization mass spectrometer in 400 milliseconds. Conditions investigated included a composition survey across the nozzle exit at 3 cm z-distance from the nozzle exit for 3 different currents. Also, a point composition survey was taken around a shock created by the presence of a blunt body.

  11. Ocular involvement in pemphigus vulgaris.

    PubMed

    Akhyani, Maryam; Keshtkar-Jafari, Alireza; Chams-Davatchi, Cheyda; Lajevardi, Vahide; Beigi, Sara; Aghazadeh, Nessa; Rayati Damavandi, Maede; Arami, Shabnam

    2014-07-01

    Pemphigus vulgaris (PV) is an autoimmune disorder affecting the skin and mucous membranes. Ocular involvement in PV has been reported but its prevalence and clinical characteristics are not well defined. This prospective cross-sectional study of 103 PV patients was designed to determine the prevalence, clinical types and epidemiological trends of ocular involvement in a population of Iranian patients with PV. Ocular involvement was present in 17 (16.5%) patients. Conjunctivitis was the most prevalent type of ocular involvement (9/17, 52.9%), followed by erosion of the palpebral conjunctiva (7/17, 41.2%). Erosion of the bulbar conjunctiva was noted in only one patient (5.9%). The most commonly reported symptoms were eye irritation (76.5%) and redness (76.5%). No significant relation was found between ocular involvement and disease activity (partial remission or relapse). Mucoid discharge was significantly more common in patients with conjunctival erosions as compared to patients with conjunctivitis (P = 0.038). We conclude that ocular involvement is not rare in PV; 16.5% of PV patients develop ocular disease independent of the disease activity and extension. Conjunctivitis is the most common type of involvement, however, palpebral conjunctival erosion is more frequent than previously realized.

  12. Twins with neonatal pemphigus vulgaris born to a mother with pemphigus vulgaris: a case report.

    PubMed

    Itsukaichi, Mina; Takakuwa, Koichi; Yamaguchi, Masayuki; Serikawa, Takehiro; Tanaka, Kenichi; Kojima, Kinuko; Sakakibara, Seiichi; Usuda, Tohei; Matsunaga, Masamichi; Hashimoto, Tsuyoshi

    2013-01-01

    Dichorionic diamniotic twins were born at 37 weeks of gestation by cesarean section to a 34-year-old primigravid Japanese woman because the first twin was in breech presentation. The mother had been diagnosed with pemphigus vulgaris prior to her pregnancy. In addition to a high antidesmoglein 3 autoantibody titer, flaccid bullae and erosions on both of the twins' lips and in their oral cavities at 13 days of age led to the diagnosis of neonatal pemphigus vulgaris. This case highlights the need for awareness that pemphigus vulgaris may not occur immediately after birth.

  13. Pemphigus vulgaris in three adolescents: the course of the disease.

    PubMed

    Popadic, Svetlana; Medenica, Ljiljana; Skiljevic, Dusan; Djakovic, Zorana; Nikolic, Milos

    2011-08-01

    We report three adolescents with pemphigus vulgaris whose disease started at the age of 13, 15 and 14 years, respectively. The course of the disease and the treatment approaches were reviewed. Pemphigus vulgaris during childhood and adolescence is a very rare disease in this part of Europe. Among 410 pemphigus vulgaris patients that we treated during the 20-year period, only three patients (0.73%) were under the age of 18 years. According to our experience, the course of pemphigus vulgaris in patients before the age of 18 years is comparable with the course of pemphigus vulgaris in adults.

  14. A case of exfoliative esophagitis with pemphigus vulgaris.

    PubMed

    Fukuchi, M; Otake, S; Naitoh, H; Shoji, H; Yamagishi, J; Suzuki, M; Yanoma, T; Kuwano, H

    2011-04-01

    Autoimmune blistering skin diseases, including pemphigus vulgaris, rarely involve the esophagus. We report a case of exfoliative esophagitis with pemphigus vulgaris. A sloughing esophageal cast observed by endoscopy was dissected esophageal squamous epithelium in all layers. Our case is the fifth case of pemphigus vulgaris associated with esophageal cast formation recorded in the medical literature. Prednisolone was administered, and both the pemphigus vulgaris and exfoliative esophagitis improved. Upon findings of exfoliative esophagitis by endoscopic examination, we should consider the coexistence of blistering skin diseases, including pemphigus vulgaris.

  15. Comparison of Biomass and Lipid Production under Ambient Carbon Dioxide Vigorous Aeration and 3% Carbon Dioxide Condition Among the Lead Candidate Chlorella Strains Screened by Various Photobioreactor Scales

    SciTech Connect

    Kobayashi, Naoko; Barnes, Austin; Jensen, Travis; Noel, Eric; Andlay, Gunjan; Rosenberg, Julian N.; Betenbaugh, Michael J.; Guarnieri, Michael T.; Oyler, George A.

    2015-09-01

    Chlorella species from the UTEX collection, classified by rDNA-based phylogenetic analysis, were screened based on biomass and lipid production in different scales and modes of culture. Lead candidate strains of C. sorokiniana UTEX 1230 and C. vulgaris UTEX 395 and 259 were compared between conditions of vigorous aeration with filtered atmospheric air and 3% CO2 shake-flask cultivation. We found that the biomass of UTEX 1230 produced 2 times higher at 652 mg L-1 dry weight under both ambient CO2 vigorous aeration and 3% CO2 conditions, while UTEX 395 and 259 under 3% CO2 increased to 3 times higher at 863 mg L-1 dry weight than ambient CO2 vigorous aeration. The triacylglycerol contents of UTEX 395 and 259 increased more than 30 times to 30% dry weight with 3% CO2, indicating that additional CO2 is essential for both biomass and lipid accumulation in UTEX 395 and 259.

  16. [Pemphigus chronicus vulgaris--case report].

    PubMed

    Spoljar, Sanja; Cavka, Mira; Tvorić, Anamarija

    2012-10-01

    Pemphigus vulgaris is a rare, chronic, autoimmune blistering skin disease of adulthood. In 50 percent of patients, mucous membrane erosions of the oral cavity are the presenting sign. Typically, patients develop flaccid blisters and erosions on the normal appearing skin and mucous membranes. Mucous membranes in other areas may also be involved. The disease is caused by IgG autoantibodies to the desmosomes inducing the loss of cell adhesion between keratinocytes, and subsequent intraepidermal blister formation. Antigens are desmoglein 3 (Dsg3) and desmoglein 1 (Dsg1) transmembrane glycoproteins. Desmoglein 3 is expressed in the lower portion of the epidermis. Alone, it is sufficient to keep mucosal surfaces intact. Desmoglein 1 is expressed more intensely in the superficial layers. Pemphigus vulgaris can be divided into two subgroups, the mucosal type and mucocutaneous type. The characteristic histologic finding is intraepidermal blister. Acantholytic keratinocytes as well as clusters of epidermal cells are seen in the blister cavity. Direct immunofluorescence examination (DIF) of perilesional skin shows a deposit of IgG, rarely IgA, and complement components (C3, C1q,C4) between the epidermal cells. The titers of circulating antibodies measured with indirect immunofluorescence examination (IIF) often correlate with the disease course. There are sporadic cases of pemphigus vulgaris associated with the use of drugs, in particular D-penicillamine and captopril. Pemphigus vulgaris has rarely evolved into pemphigus foliaceus, and vice versa. Very uncommon, pemphigus vulgaris or pemphigus foliaceus has been associated with bullous pemphigoid in the same patient. We present an unusual case of pemphigus vulgaris in an adult female patient.

  17. Controlling Arc Length in Plasma Welding

    NASA Technical Reports Server (NTRS)

    Iceland, W. F.

    1986-01-01

    Circuit maintains arc length on irregularly shaped workpieces. Length of plasma arc continuously adjusted by control circuit to maintain commanded value. After pilot arc is established, contactor closed and transfers arc to workpiece. Control circuit then half-wave rectifies ac arc voltage to produce dc control signal proportional to arc length. Circuit added to plasma arc welding machines with few wiring changes. Welds made with circuit cleaner and require less rework than welds made without it. Beads smooth and free of inclusions.

  18. THERAPEUTIC AGENTS IN ACNE VULGARIS. I. TETRACYCLINE.

    PubMed

    STEWART, W D; MADDIN, S; NELSON, A J; DANTO, J L

    1963-11-23

    A total of 120 consecutive patients with pustular and cystic acne vulgaris were selected for study. Patients were assigned a placebo and a tetracycline medication in a random method. Of the 53 patients who were given tetracycline, 45 showed some response, which was fair in 19 and excellent in 26. Of the 55 patients who received placebo, 24 showed no response while 31 showed some improvement. No side effects were reported. The difference in response between the two groups is statistically significant. It is concluded that administration of 250 mg. tetracycline four times daily, even for periods as short as two weeks, enhances the likelihood of improvement of cystic or pustular acne vulgaris.

  19. Lupus vulgaris: unusual presentations over the face.

    PubMed

    Khandpur, S; Reddy, B S N

    2003-11-01

    Lupus vulgaris (LV) is the most common morphological variant of cutaneous tuberculosis. However, the occurrence of bizarre clinical presentations over atypical sites often leads to misdiagnosis and inappropriate treatment causing significant morbidity. This report seeks to highlight two unusual cases of lupus vulgaris occurring on the face of immunocompetent women and remarkably mimicking periorbital cellulitis and basal cell carcinoma, respectively. The diagnosis was confirmed by histopathology, an enzyme-linked immunosorbent assay (ELISA) test for Mycobacterium tuberculosis and polymerase chain reaction (PCR). With four-drug antitubercular therapy, both patients had a dramatic response.

  20. Models for Jupiter's decametric arcs

    NASA Technical Reports Server (NTRS)

    Warwick, J. W.

    1981-01-01

    Arc-shaped structures that dominate Jupiter's decametric emission are discussed in terms of a magnetic fine structure. The sequence of arcs manifest the occurence of widespread fine structures similar to the white ovals on Jupiter's visible surface. An arc concave toward increasing time occurs at the east limb passage, and an arc convex occurs at the west limb passage, which is consistent with the early source producing vertex early arcs, and the late source producing vertex late arcs. Due to the geometry of the Io plasma torus (IPT) which is arranged so that Io skims the northern surface of the IPT, for any connection between Io and Jupiter's surface that involves Alfven waves, the propagation time, the refraction and the directional defocusing of these waves must be strongly influenced by the amount of Alfven wave path length between the instantaneous position of Io and the surface of the IPT.

  1. Photodynamic therapy of acne vulgaris.

    NASA Astrophysics Data System (ADS)

    Ershova, Ekaterina Y.; Karimova, Lubov N.; Kharnas, Sergey S.; Kuzmin, Sergey G.; Loschenov, Victor B.

    2003-06-01

    Photodynamic therapy (PDT) with topical 5-aminolevulinic acid (ALA) was tested for the treatment of acne vulgaris. Patients with acne were treated with ALA plus red light. Ten percent water solution of ALA was applied with 1,5-2 h occlusion and then 18-45 J/cm2 630 nm light was given. Bacterial endogenous porphyrins fluorescence also was used for acne therapy. Treatment control and diagnostics was realized by fluorescence spectra and fluorescence image. Light sources and diagnostic systems were used: semiconductor laser (λ=630 nm, Pmax=1W), (LPhT-630-01-BIOSPEC); LED system for PDT and diagnostics with fluorescent imager (λ=635 nm, P=2W, p=50 mW/cm2), (UFPh-630-01-BIOSPEC); high sensitivity CCD video camera with narrow-band wavelength filter (central wavelength 630 nm); laser electronic spectrum analyzer for fluorescent diagnostics and photodynamic therapy monitoring (LESA-01-BIOSPEC). Protoporphyrin IX (PP IX) and endogenous porphyrins concentrations were measured by fluorescence at wavelength, correspondingly, 700 nm and 650 nm. It was shown that topical ALA is converted into PP IX in hair follicles, sebaceous glands and acne scars. The amount of resulting PP IX is sufficient for effective PDT. There was good clinical response and considerable clearance of acne lesion. ALA-PDT also had good cosmetic effect in treatment acne scars. PDT with ALA and red light assist in opening corked pores, destroying Propionibacterium acnes and decreasing sebum secretion. PDT treatment associated with several adverse effects: oedema and/or erytema for 3-5 days after PDT, epidermal exfoliation from 5th to 10th day and slight pigmentation during 1 month after PDT. ALA-PDT is effective for acne and can be used despite several side effects.

  2. Complementary therapies for acne vulgaris

    PubMed Central

    Cao, Huijuan; Yang, Guoyan; Wang, Yuyi; Liu, Jian Ping; Smith, Caroline A; Luo, Hui; Liu, Yueming

    2015-01-01

    Background Acne is a chronic skin disease characterised by inflamed spots and blackheads on the face, neck, back, and chest. Cysts and scarring can also occur, especially in more severe disease. People with acne often turn to complementary and alternative medicine (CAM), such as herbal medicine, acupuncture, and dietary modifications, because of their concerns about the adverse effects of conventional medicines. However, evidence for CAM therapies has not been systematically assessed. Objectives To assess the effects and safety of any complementary therapies in people with acne vulgaris. Search methods We searched the following databases from inception up to 22 January 2014: the Cochrane Skin Group Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL; 2014, Issue 1), MEDLINE (from 1946), Embase (from 1974), PsycINFO (from 1806), AMED (from 1985), CINAHL (from 1981), Scopus (from 1966), and a number of other databases listed in the Methods section of the review. The Cochrane CAM Field Specialised Register was searched up to May 2014. We also searched five trials registers and checked the reference lists of articles for further references to relevant trials. Selection criteria We included parallel-group randomised controlled trials (or the first phase data of randomised cross-over trials) of any kind of CAM, compared with no treatment, placebo, or other active therapies, in people with a diagnosis of acne vulgaris. Data collection and analysis Three authors collected data from each included trial and evaluated the methodological quality independently. They resolved disagreements by discussion and, as needed, arbitration by another author. Main results We included 35 studies, with a total of 3227 participants. We evaluated the majority as having unclear risk of selection, attrition, reporting, detection, and other biases. Because of the clinical heterogeneity between trials and the incomplete data reporting, we could only include four

  3. Joan of Arc.

    PubMed

    Foote-Smith, E; Bayne, L

    1991-01-01

    For centuries, romantics have praised and historians and scientists debated the mystery of Joan of Arc's exceptional achievements. How could an uneducated farmer's daughter, raised in harsh isolation in a remote village in medieval France, have found the strength and resolution to alter the course of history? Hypotheses have ranged from miraculous intervention to creative psychopathy. We suggest, based on her own words and the contemporary descriptions of observers, that the source of her visions and convictions was in part ecstatic epileptic auras and that she joins the host of creative religious thinkers suspected or known to have epilepsy, from St. Paul and Mohammed to Dostoevsky, who have changed western civilization.

  4. APPARATUS FOR ARC WELDING

    DOEpatents

    Lingafelter, J.W.

    1960-04-01

    An apparatus is described in which a welding arc created between an annular electrode and a workpiece moves under the influence of an electromagnetic field about the electrode in a closed or annular path. This mode of welding is specially suited to the enclosing of nuclear-fuel slugs in a protective casing. For example, a uranium slug is placed in an aluminum can, and an aluminum closure is welded to the open end of the can along a closed or annular path conforming to the periphery of the end closure.

  5. Arcing on dc power systems

    NASA Technical Reports Server (NTRS)

    Moores, Greg; Heller, R. P.; Sutanto, Surja; Dugal-Whitehead, Norma R.

    1992-01-01

    Unexpected and undesirable arcing on dc power systems can produce hazardous situations aboard space flights. The potential for fire and shock might exist in a situation where there is a broken conductor, a loose power connection, or a break in the insulation of the power cable. Such arcing has been found to be reproducible in a laboratory environment. Arcing tests show that the phenomena can last for several seconds and yet be undetectable by present protection schemes used in classical power relaying and remote power controller applications. This paper characterizes the arcing phenomena and suggests future research that is needed.

  6. Ingestion of Chlorella reduced the oxidation of erythrocyte membrane lipids in senior Japanese subjects.

    PubMed

    Miyazawa, Taiki; Nakagawa, Kiyotaka; Takekoshi, Hideo; Higuchi, Ohki; Kato, Shunji; Kondo, Momoko; Kimura, Fumiko; Miyazawa, Teruo

    2013-01-01

    Accumulation of phospholipid hydroperoxide (PLOOH) in erythrocyte membranes is an abnormality found in patients with senile dementia, including those with Alzheimer's disease. In our previous studies, dietary xanthophylls (polar carotenoids such as lutein) were hypothesized to inhibit lipid peroxidation. In the present study, we conducted a randomized, double-blind, placebo-controlled human trial to assess the impact for a total of 2 months Chlorella supplementation (8 g Chlorella/day/person; equivalent to 22.9 mg lutein/day/person) on PLOOH and carotenoid concentrations in erythrocytes as well as plasma of 12 normal senior subjects. After 1 or 2 months of treatment, erythrocytes and plasma lutein concentrations increased in the Chlorella group but not in the placebo group. In the Chlorella-supplemented group, erythrocyte PLOOH concentrations after a total of 2 months of treatment were lower than the concentrations before supplementation. These results suggest that Chlorella ingestion improved erythrocyte antioxidant status and lowered PLOOH concentrations. These reductions might contribute to maintaining the normal function of erythrocytes and prevent the development of senile dementia.

  7. Growth kinetics and yield study on Chlorella pyrenoidosa in chemically defined media

    SciTech Connect

    Joung, J.J.; Akin, C.

    1983-01-01

    A Chlorella culture free from heterotrophic bacteria was obtained by eliminating the bacteria with successive use of antibiotics and agar plants. The purified Chlorella was cultured in chemically defined media. Under a photon flux (16.7 mw/cmS) similar to insolation, both heterotrophic and mixotrophic cultures were luxurious but the growth rates of autotrophic cultures were reduced substantially. The Chlorella culture grew most rapidly at 30 C in the absence of heterotrophic bacteria, and the highest specific growth rates were 1.43 x 10 h and 0.46 x 10 h for mixotrophic and autotrophic cultures, respectively. The highest photosynthetic efficiency over its growth period was 2.9% for autotrophic cultures. Elimination of heterotrophic bacteria from Chlorella cultures improved the algal growth rate as well as biomass yield significantly. A parasite of 0.1- m size was identified. The motile microorganism played an important role in the growth of the Chlorella and appeared to be common to green algae. 16 references, 2 tables.

  8. Autoinoculation lupus vulgaris of the perineum.

    PubMed

    Sehgal, V N; Chaudhry, A K; Gupta, R

    1991-08-01

    The case of a young heterosexual male, with a 7 year history of an asymptomatic progressive plaque over the right side of the perineum is described, which 4 years later involved the left perineum and scrotal skin, indicating autoinoculation. The diagnosis of lupus vulgaris was made by strongly positive tuberculin test, histopathology, and a favourable response to a short course of intensive antitubercular therapy.

  9. Ichthyosis vulgaris: the filaggrin mutation disease.

    PubMed

    Thyssen, J P; Godoy-Gijon, E; Elias, P M

    2013-06-01

    Ichthyosis vulgaris is caused by loss-of-function mutations in the filaggrin gene (FLG) and is characterized clinically by xerosis, scaling, keratosis pilaris, palmar and plantar hyperlinearity, and a strong association with atopic disorders. According to the published studies presented in this review article, FLG mutations are observed in approximately 7·7% of Europeans and 3·0% of Asians, but appear to be infrequent in darker-skinned populations. This clinical review article provides an overview of ichthyosis vulgaris epidemiology, related disorders and pathomechanisms. Not only does ichthyosis vulgaris possess a wide clinical spectrum, recent studies suggest that carriers of FLG mutations may have a generally altered risk of developing common diseases, even beyond atopic disorders. Mechanistic studies have shown increased penetration of allergens and chemicals in filaggrin-deficient skin, and epidemiological studies have found higher levels of hand eczema, irritant contact dermatitis, nickel sensitization and serum vitamin D levels. When relevant, individuals should be informed about an increased risk of developing dermatitis when repeatedly or continuously exposed to nickel or irritants. Moreover, with our current knowledge, individuals with ichthyosis vulgaris should be protected against neonatal exposure to cats to prevent atopic dermatitis and should abstain from smoking to prevent asthma. Finally, they should be advised against excessive exposure to factors that decrease skin barrier functions and increase the risk of atopic dermatitis.

  10. Squamous cell carcinoma associated with lupus vulgaris.

    PubMed

    Gooptu, C; Marks, N; Thomas, J; James, M P

    1998-05-01

    Squamous cell carcinomas are known to arise in certain chronic, scarring dermatoses and also to be associated with exposure to ultraviolet radiation. We now report a case arising in a plaque of lupus vulgaris, the patient having received radiation from a Finsen lamp as a child for a tuberculous abscess in that region.

  11. Chlorella Virus Encoded Deoxyuridine triphosphatases Exhibit different Temperature Optima

    SciTech Connect

    Zhang,Y.; Moriyama, H.; Homma, K.; Van Etten, J.

    2005-01-01

    A putative deoxyuridine triphosphatase (dUTPase) gene from chlorella virus PBCV-1 was cloned, and the recombinant protein was expressed in Escherichia coli. The recombinant protein has dUTPase activity and requires Mg{sup 2+} for optimal activity, while it retains some activity in the presence of other divalent cations. Kinetic studies of the enzyme revealed a K{sub m} of 11.7 {mu}M, a turnover k{sub cat} of 6.8 s{sup -1}, and a catalytic efficiency of k{sub cat}/K{sub m} = 5.8 x 105 M{sup -1} s{sup -1}. dUTPase genes were cloned and expressed from two other chlorella viruses IL-3A and SH-6A. The two dUTPases have similar properties to PBCV-1 dUTPase except that IL-3A dUTPase has a lower temperature optimum (37{sup o}C) than PBCV-1 dUTPase (50{sup o}C). The IL-3A dUTPase differs from the PBCV-1 enzyme by nine amino acids, including two amino acid substitutions, Glu81{yields}Ser81 and Thr84{yields}Arg84, in the highly conserved motif III of the proteins. To investigate the difference in temperature optima between the two enzymes, homology modeling and docking simulations were conducted. The results of the simulation and comparisons of amino acid sequence suggest that adjacent amino acids are important in the temperature optima. To confirm this suggestion, three site-directed amino acid substitutions were made in the IL-3A enzyme: Thr84{yields}Arg84, Glu81{yields}Ser81, and Glu81{yields}Ser81 plus Thr84{yields}Arg84. The single substitutions affected the optimal temperature for enzyme activity. The temperature optimum increased from 37 to 55{sup o}C for the enzyme containing the two amino acid substitutions. We postulate that the change in temperature optimum is due to reduction in charge and balkiness in the active cavity that allows more movement of the ligand and protein before the enzyme and substrate complex is formed.

  12. Heterotrophic Growth and Production of Xanthophylls by Chlorella pyrenoidosa

    PubMed Central

    Theriault, Robert J.

    1965-01-01

    The growth and level of xanthophylls of several representative species of green algae were investigated as a possible source of pigmentation for the egg yolk and broiler markets. Chlorella pyrenoidosa 7-11-05 was selected for fermentation studies because of its high level of xanthophylls and wide temperature range for growth. The heterotrophic metabolism was preferred because of the ease of adaptability to present fermentation equipment. When used as the sole carbon source, glucose was the only sugar, among many tested, that gave appreciable growth in illuminated shaken flasks. A dry cell weight of 90 g per liter and total xanthophylls of 450 mg per liter were obtained from 190 g per liter of glucose monohydrate in 168-hr illuminated shaken flasks. Higher levels of glucose decreased yields. In combination with glucose, monosaccharides, such as fructose and galactose, were readily assimilated. The 7-11-05 strain was adapted to galactose as the sole carbon source after six vegetative passages. Light of the proper intensity and duration stimulated total xanthophylls approximately 35%. The effect on dry cell weight and total xanthophylls of seven antibiotics added at various levels in shaken flasks was studied. Erythromycin was essentially stable throughout the fermentation and nontoxic up to 25 μg/ml, with only slight toxicity at higher levels. Both erythromycin and ristocetin were effective in controlling a high incidence of bacterial contamination in 30-liter fermentors. With the higher agitation and aeration rates possible in 30-liter fermentors, dry cell weights in excess of 100 g per liter and total xanthophylls of 467 to 512 mg per liter were readily obtained from 230 to 260 g per liter of glucose in 162-hr illuminated batch-type fermentations. Continuous-feed runs yielded a dry cell weight of 302 g per liter and total xanthophylls of 650 mg per liter from 520 g per liter of glucose. The type of Chlorella cell produced was an important consideration with

  13. Electric arc welding gun

    DOEpatents

    Luttrell, Edward; Turner, Paul W.

    1978-01-01

    This invention relates to improved apparatus for arc welding an interior joint formed by intersecting tubular members. As an example, the invention is well suited for applications where many similar small-diameter vertical lines are to be welded to a long horizontal header. The improved apparatus includes an arc welding gun having a specially designed welding head which is not only very compact but also produces welds that are essentially free from rolled-over solidified metal. The welding head consists of the upper end of the barrel and a reversely extending electrode holder, or tip, which defines an acute angle with the barrel. As used in the above-mentioned example, the gun is positioned to extend upwardly through the vertical member and the joint to be welded, with its welding head disposed within the horizontal header. Depending on the design of the welding head, the barrel then is either rotated or revolved about the axis of the vertical member to cause the electrode to track the joint.

  14. Alternating-Polarity Arc Welding

    NASA Technical Reports Server (NTRS)

    Schwinghamer, R. J.

    1987-01-01

    Brief reversing polarity of welding current greatly improves quality of welds. NASA technical memorandum recounts progress in art of variable-polarity plasma-arc (VPPA) welding, with emphasis on welding of aluminum-alloy tanks. VPPA welders offer important advantages over conventional single-polarity gas/tungsten arc welders.

  15. TAMA. TIGER Arc Modification Application

    SciTech Connect

    Armstrong, H

    1994-06-03

    The application enables the geometric correction of TIGER arcs to a more accurate spatial data set. This is done in a structured automated environment according to Census Bureau guidelines and New Mexico state GIS standards. Arcs may be deleted, added, combined, split, and moved relative to a coverage or image displayed in the background.

  16. High-density fermentation of microalga Chlorella protothecoides in bioreactor for microbio-diesel production.

    PubMed

    Xiong, Wei; Li, Xiufeng; Xiang, Jinyi; Wu, Qingyu

    2008-02-01

    Agal-fermentation-based microbio-diesel production was realized through high-cell-density fermentation of Chlorella protothecoides and efficient transesterification process. Cell density achieved was 16.8 g l(-1) in 184 h and 51.2 g l(-1) in 167 h in a 5-l bioreactor by performing preliminary and improved fed-batch culture strategy, respectively. The lipid content was 57.8, 55.2, and 50.3% of cell dry weight from batch, primary, and improved fed-batch culture in 5-l bioreactor. Transesterification was catalyzed by immobilized lipase, and the conversion rate reached up to 98%. The properties of biodiesel from Chlorella were comparable to conventional diesel fuel and comply with US standard for Biodiesel. In a word, the approach including high-density fermentation of Chlorella and enzymatic transesterification process were set up and proved to be a promising alternative for biodiesel production.

  17. Lipid production by a CO₂-tolerant green microalga, Chlorella sp. MRA-1.

    PubMed

    Zheng, Yanlin; Yuan, Cheng; Liu, Junhan; Hu, Guangrong; Li, Fuli

    2014-05-01

    Since CO2 concentrations in industrial flue gases are usually 10%-20%, one of the prerequisites for efficient CO2 removal by algae is the level of tolerance of microalgal species to exposure to high concentrations of CO2. A newly isolated microalgal strain, Chlorella sp. MRA-1, could retain growth with high concentrations of CO2 up to 15%. The highest lipid productivity for Chlorella sp. MRA-1 was 0.118 g/l/day with a 5% CO2 concentration. Octadecenoic acid and hexadecanoic acid, the main components of biodiesel, accounted for 70% of the total fatty acids. A lipid content of 52% of dry cell weight was achieved with limited amounts of nitrogen. Chlorella sp. MRA-1 seems to be an ideal candidate for biodiesel production when cultured with high concentrations of CO2.

  18. Cell-wall disruption and lipid/astaxanthin extraction from microalgae: Chlorella and Haematococcus.

    PubMed

    Kim, Dong-Yeon; Vijayan, Durairaj; Praveenkumar, Ramasamy; Han, Jong-In; Lee, Kyubock; Park, Ji-Yeon; Chang, Won-Seok; Lee, Jin-Suk; Oh, You-Kwan

    2016-01-01

    Recently, biofuels and nutraceuticals produced from microalgae have emerged as major interests, resulting in intensive research of the microalgal biorefinery process. In this paper, recent developments in cell-wall disruption and extraction methods are reviewed, focusing on lipid and astaxanthin production from the biotechnologically important microalgae Chlorella and Haematococcus, respectively. As a common, critical bottleneck for recovery of intracellular components such as lipid and astaxanthin from these microalgae, the composition and structure of rigid, thick cell-walls were analyzed. Various chemical, physical, physico-chemical, and biological methods applied for cell-wall breakage and lipid/astaxanthin extraction from Chlorella and Haematococcus are discussed in detail and compared based on efficiency, energy consumption, type and dosage of solvent, biomass concentration and status (wet/dried), toxicity, scalability, and synergistic combinations. This report could serve as a useful guide to the implementation of practical downstream processes for recovery of valuable products from microalgae including Chlorella and Haematococcus.

  19. Of Eggs and Arcs

    NASA Astrophysics Data System (ADS)

    Burns, Joseph A.; Thomas, P. C.; Helfenstein, P.; Tiscareno, M. S.; Hedman, M. M.; Agarwal, M.

    2012-10-01

    New scenarios for the origins of Saturn’s rings/interior moons have directed scientific attention to the region just exterior to Saturn’s main rings. Four satellites (Aegaeon = Ae; Anthe = An; Methone = Me; Pallene = Pa) discovered by the Cassini mission on either side of Mimas’s orbit perhaps comprise a distinct class of ring-moon. They are tiny (R = 0.3-2.5 km); three (AeAnMe) are trapped in co-rotation resonances with Mimas and reside within ring-arcs; and at least two (MePa) have remarkably regular shapes. Images with pixel scales as fine as 27 m taken in May 2012 reveal Methone to be ovoid within 10 m (from sub-pixel limb detection) and devoid of any craters (>130 m) across its 9 km2 of surface; Pallene and even tiny Aegaeon have similar appearances in lesser-quality images. Numerical simulations demonstrate that particles comprising the surrounding ring-arcs populate the same resonances as their embedded moons; escape speeds from the moons are < 0.5 m/s, smaller than the 2 m/s that dynamically characterize the resonant well. We investigate the gentle transfer of particles back and forth between the ring-arcs and any embedded bodies. In this environment, the moons’ shapes are smooth equipotentials; electrostatic effects may also determine how grains settle to surfaces. Considering these shapes to represent equipotential surfaces for rotating, tidally distorted, homogeneous bodies, we infer mean satellite densities of 250+/-60 (Pa), 310+/-30 (Me), and 540+/-120 (Ae) kg m-3. About half of Methone’s leading hemisphere is covered by a sharply bounded, lemon-shaped, relatively dark region, having a form reminiscent of Mimas’s thermal anomaly (Howett et al. 2011). Its (601 nm) albedo is 13% lower than the bounding brighter material. An irregularly shaped, even-darker (by 4%) blotch straddles the apex of the moon’s motion. Impacts with circum-planetary meteoroids and plasma are likely responsible for these features.

  20. Gastrointestinal Elimination of Perfluorinated Compounds Using Cholestyramine and Chlorella pyrenoidosa

    PubMed Central

    Genuis, Stephen J.; Curtis, Luke; Birkholz, Detlef

    2013-01-01

    Background. While perfluorinated compounds (PFCs) are a family of commonly used synthetic compounds with many applications, some PFCs remain persistent within the human body due, in part, to enterohepatic recirculation and renal tubular reabsorption. With increasing recognition of potential harm to human health associated with PFC bioaccumulation, interventions to facilitate elimination of these toxicants are welcome in order to potentially preclude or overcome illness. Minimal research has been undertaken thus far on methods to accelerate human clearance of PFCs. Methods. To test for possible oral treatments to hasten PFC elimination, a group of individuals with elevated PFC levels was treated with cholestyramine (CSM) and, after a break, was subsequently treated with Chlorella pyrenoidosa (CP). Stool samples were collected from all participants (i) prior to any treatment, (ii) during treatment with CSM, and (iii) during treatment with CP. Results. With CSM treatment, significant levels of three distinct PFCs were found in all stools, while levels were mostly undetectable prior to treatment. Following treatment with oral CP, undetectable or very low levels of all PFCs were noted in each sample tested. Conclusion. CSM appears to facilitate elimination of some common PFCs and may have some role in the clinical management of patients with accrued PFCs. PMID:24106616

  1. Chlorella viruses contain genes encoding a complete polyamine biosynthetic pathway

    PubMed Central

    Baumann, Sascha; Sander, Adrianne; Gurnon, James R.; Yanai-Balser, Giane; VanEtten, James L.; Piotrowski, Markus

    2007-01-01

    Two genes encoding the putative polyamine biosynthetic enzymes agmatine iminohydrolase (AIH) and N-carbamoylputrescine amidohydrolase (CPA) were cloned from the chloroviruses PBCV-1, NY-2A and MT325. They were expressed in Escherichia coli to form C-terminal (His)6-tagged proteins and the recombinant proteins were purified by Ni2+- binding affinity chromatography. The biochemical properties of the two enzymes are similar to AIH and CPA enzymes from Arabidopsis thaliana and Pseudomonas aeruginosa. Together with the previously known virus genes encoding ornithine/arginine decarboxlyase (ODC/ADC) and homospermidine synthase, the chloroviruses have genes that encode a complete set of functional enzymes that synthesize the rare polyamine homospermidine from arginine via agmatine, N-carbamoylputrescine and putrescine. The PBCV-1 aih and cpa genes are expressed early during virus infection together with the odc/adc gene, suggesting that biosynthesis of putrescine is important in early stages of viral replication. The aih and cpa genes are widespread in the chlorella viruses. PMID:17101165

  2. Assessment of photosynthesis regulation in mixotrophically cultured microalga Chlorella sorokiniana

    DOE PAGES

    Li, Tingting; Kirchhoff, Helmut; Gargouri, Mahmoud; ...

    2016-07-19

    Mixotrophic growth of microalgae offers great potential as an efficient strategy for biofuel production. In this study, photosynthetic regulation of mixotrophically cultured Chlorella sorokiniana cells was systematically evaluated. Mixotrophic cells in the exponential growth phase showed the highest photosynthetic activity, where maximum photosynthetic O2 evolution was approximately 3- and 4-fold higher than cells in the same phase grown photoautotrophically in 1% CO2 (in air) and air, respectively. Additionally, characteristic chlorophyll fluorescence parameters demonstrated that no limitation in electron transport downstream of PSII was detected in mixotrophic cells. Up-regulation of photosynthetic activity was associated with high total ribulose-1, 5-bisphosphate carboxylase/oxygenase (Rubisco)more » carboxylase activity and expression level of phosphoribulokinase (PRK). After 3 days, photosynthetic O2 evolution of mixotrophic cells that went to the stationary phase, was strongly reduced, with reduced photochemical efficiency and reorganization of the PSII complex. Simultaneously, enzymatic activity for Rubisco carboxylase and mRNA levels of Rubisco and PRK diminished. Importantly, there was almost no non-photochemical quenching for mixotrophic cells, whether grown in log or stationary phase. A decline in the quantum efficiency of PSII and an oxidized plastoquinone pool (PQ pool) was observed under N-depleted conditions during mixotrophic growth. Finally, these results demonstrate that photosynthesis is regulated differently in mixotrophically cultured C. sorokiniana cells than in cells grown under photoautotrophic conditions, with a particularly strong impact by nitrogen levels in the cells.« less

  3. Lutein recovery from Chlorella sp. ESP-6 with coagulants.

    PubMed

    Utomo, Rhesa Pramudita; Chang, Yin-Ru; Lee, Duu-Jong; Chang, Jo-Shu

    2013-07-01

    Production of algal lutein included cell cultivation, biomass harvesting, cell wall disruption, and subsequent purification if needed. This work cultivated Chlorella sp. ESP-6 cells in photobioreactor to a biomass content of 1.1 gl(-1) and then the freezing-grinding, ultrasonic treatment (20 and 42kHz) and microwave treatment were used to disrupt the cell walls for recover intracellular lutein. The grinding recovered more lutein than ultrasound or microwave pretreatment. Single coagulation using >30 mgl(-1) chitosan or dual-conditioning using 10 mg l(-1) polyaluminum chloride and 10 mgl(-1) chitosan effectively enhance sedimentation and membrane filtration efficiency of algal suspensions. However, the presence of coagulants lowers the lutein yield from algal biomass in the subsequent 20 kHz ultrasound treatment and purification process. Simulation results revealed affine adsorption of lutein onto chitosan molecules via hydroxyl-amine interaction. The possible drawback by pre-treatment stage should be considered together with the subsequent recovery stage in whole process assessment.

  4. A functional calcium-transporting ATPase encoded by chlorella viruses

    PubMed Central

    Bonza, Maria Cristina; Martin, Holger; Kang, Ming; Lewis, Gentry; Greiner, Timo; Giacometti, Sonia; Van Etten, James L.; De Michelis, Maria Ida; Thiel, Gerhard; Moroni, Anna

    2010-01-01

    Calcium-transporting ATPases (Ca2+ pumps) are major players in maintaining calcium homeostasis in the cell and have been detected in all cellular organisms. Here, we report the identification of two putative Ca2+ pumps, M535L and C785L, encoded by chlorella viruses MT325 and AR158, respectively, and the functional characterization of M535L. Phylogenetic and sequence analyses place the viral proteins in group IIB of P-type ATPases even though they lack a typical feature of this class, a calmodulin-binding domain. A Ca2+ pump gene is present in 45 of 47 viruses tested and is transcribed during virus infection. Complementation analysis of the triple yeast mutant K616 confirmed that M535L transports calcium ions and, unusually for group IIB pumps, also manganese ions. In vitro assays show basal ATPase activity. This activity is inhibited by vanadate, but, unlike that of other Ca2+ pumps, is not significantly stimulated by either calcium or manganese. The enzyme forms a 32P-phosphorylated intermediate, which is inhibited by vanadate and not stimulated by the transported substrate Ca2+, thus confirming the peculiar properties of this viral pump. To our knowledge this is the first report of a functional P-type Ca2+-transporting ATPase encoded by a virus. PMID:20573858

  5. A functional calcium-transporting ATPase encoded by chlorella viruses.

    PubMed

    Bonza, Maria Cristina; Martin, Holger; Kang, Ming; Lewis, Gentry; Greiner, Timo; Giacometti, Sonia; Van Etten, James L; De Michelis, Maria Ida; Thiel, Gerhard; Moroni, Anna

    2010-10-01

    Calcium-transporting ATPases (Ca(2+) pumps) are major players in maintaining calcium homeostasis in the cell and have been detected in all cellular organisms. Here, we report the identification of two putative Ca(2+) pumps, M535L and C785L, encoded by chlorella viruses MT325 and AR158, respectively, and the functional characterization of M535L. Phylogenetic and sequence analyses place the viral proteins in group IIB of P-type ATPases even though they lack a typical feature of this class, a calmodulin-binding domain. A Ca(2+) pump gene is present in 45 of 47 viruses tested and is transcribed during virus infection. Complementation analysis of the triple yeast mutant K616 confirmed that M535L transports calcium ions and, unusually for group IIB pumps, also manganese ions. In vitro assays show basal ATPase activity. This activity is inhibited by vanadate, but, unlike that of other Ca(2+) pumps, is not significantly stimulated by either calcium or manganese. The enzyme forms a (32)P-phosphorylated intermediate, which is inhibited by vanadate and not stimulated by the transported substrate Ca(2+), thus confirming the peculiar properties of this viral pump. To our knowledge this is the first report of a functional P-type Ca(2+)-transporting ATPase encoded by a virus.

  6. Removal and reductive dechlorination of triclosan by Chlorella pyrenoidosa.

    PubMed

    Wang, Shujuan; Wang, Xian; Poon, Karen; Wang, Yini; Li, Shangfu; Liu, Hongxia; Lin, Shuhai; Cai, Zongwei

    2013-09-01

    Triclosan that is widely used as antimicrobial agent has been detected as contaminant in various aquatic environments. In this work, removal and biodegradation of triclosan in water by using a ubiquitous green alga, Chlorella pyrenoidosa was investigated. When C. pyrenoidosa was exposed to a series concentration of triclosan from 100 to 800ngmL(-1), more than 50% of triclosan was eliminated by algal uptake from the culture medium during the first 1h exposure and reached equilibrium after the 6h treatment. In the biodegradation experiments, a removal percentage of 77.2% was obtained after C. pyrenoidosa was cultivated with 800ngmL(-1) triclosan for 96h. A major metabolite from the reductive dechlorination of triclosan was identified by using liquid chromatography coupled with electrospray ionization-mass spectrometry. The ultrastructural morphology of algal cells grown in the presence of triclosan was observed by using transmission electron microscopy and the growth of algal cells was detected. It was found that the trilcosan treatment resulted in the disruption of the chloroplast and the release of organic material into aquatic environment, which indicated that triclosan may affect membrane metabolism.

  7. Arc fault detection system

    DOEpatents

    Jha, K.N.

    1999-05-18

    An arc fault detection system for use on ungrounded or high-resistance-grounded power distribution systems is provided which can be retrofitted outside electrical switchboard circuits having limited space constraints. The system includes a differential current relay that senses a current differential between current flowing from secondary windings located in a current transformer coupled to a power supply side of a switchboard, and a total current induced in secondary windings coupled to a load side of the switchboard. When such a current differential is experienced, a current travels through a operating coil of the differential current relay, which in turn opens an upstream circuit breaker located between the switchboard and a power supply to remove the supply of power to the switchboard. 1 fig.

  8. Arc fault detection system

    DOEpatents

    Jha, Kamal N.

    1999-01-01

    An arc fault detection system for use on ungrounded or high-resistance-grounded power distribution systems is provided which can be retrofitted outside electrical switchboard circuits having limited space constraints. The system includes a differential current relay that senses a current differential between current flowing from secondary windings located in a current transformer coupled to a power supply side of a switchboard, and a total current induced in secondary windings coupled to a load side of the switchboard. When such a current differential is experienced, a current travels through a operating coil of the differential current relay, which in turn opens an upstream circuit breaker located between the switchboard and a power supply to remove the supply of power to the switchboard.

  9. [Effects of light quality on the growth characteristics and biochemical component of Chlorella pyrenoidosa].

    PubMed

    Tang, Qing-Qing; Fang, Zhi-Guo; Ji, Wen-Wen; Xia, Hui-Long

    2014-11-01

    Effect of light quality, including red light, blue light, white light, red and blue mixing light with ratios of 8: 1, 8:2 and 8 : 3, on the growth characteristics and biochenmical composition of Chlorella pyrenoidosa was investigated based on light emitting diode (LED). Results showed that Chlorella pyrenoidosa grew best under blue light, and the optical density, specific growth rate and biomass of Chlorella pyrenoidosa was about 2.4, 0.10 d(-1) and 0.64 g x L(-1), respectively, while the optical density of Chlorella pyrenoidosa was between 1.0 and 1.7, the specific growth rate was between 0.07-0.10 d(-1) and the biomass was between 0.27 and 0.38 g x L(-1) under other light quality after 30 days of cultivation. Under blue light, the optical density, specific growth rate and biomass of Chlorella pyrenoidosa was approximately 2.05 times, 1.33 times and 2.06 times higher than red light, respectively. Moreover, red and blue mixing light was conducive to the synthesis of chlorophyll a and β-carotene of Chlorella pyrenoidosa, and blue light could promote the synthesis of chlorophyll b. Chlorophyll a and carotenoids content of Chlorella pyrenoidosa was 13.5 mg xg(-1) and 5.8 mg x g(-1) respectively under red and blue mixing light with a ratio of 8:1, while it was 8.4 mg x g(-1) and 3.6 mg x g(-1) respectively under blue light. Red and blue mixing light was more conducive to protein and total lipid content per dry cell of Chlorella pyrenoidosa. Protein and total lipid content was 489.3 mg x g(-1) and 311.2 mg x g(-1) under red and blue mixing light with a ratio of 8 : 3, while it was 400.9 mg x g(-1) and 231.9 mg x g(-1) respectively under blue light.

  10. Complete genome sequence of mitochondrial DNA (mtDNA) of Chlorella sorokiniana.

    PubMed

    Orsini, Massimiliano; Costelli, Cristina; Malavasi, Veronica; Cusano, Roberto; Concas, Alessandro; Angius, Andrea; Cao, Giacomo

    2016-01-01

    The complete sequence of mitochondrial genome of the Chlorella sorokiniana strain (SAG 111-8 k) is presented in this work. Within the Chlorella genus, it represents the second species with a complete sequenced and annotated mitochondrial genome (GenBank accession no. KM241869). The genome consists of circular chromosomes of 52,528 bp and encodes a total of 31 protein coding genes, 3 rRNAs and 26 tRNAs. The overall AT contents of the C. sorokiniana mtDNA is 70.89%, while the coding sequence is of 97.4%.

  11. A case of pemphigus vulgaris with esophageal involvement.

    PubMed

    Amichai, B; Grunwald, M H; Gasper, N; Finkelstein, E; Halevy, S

    1996-03-01

    Esophageal involvement in pemphigus vulgaris is rare, found more in women than in men, and can be the only manifestation of pemphigus. Esophageal involvement had been reported only among patients with pemphigus vulgaris and not in patients with other forms of pemphigus. We describe a case of pemphigus vulgaris in which the esophagus was severely involved with only few oral lesions and no involvement of the skin or oropharynx.

  12. Occurrence of isoflavonoids in Brazilian common bean germplasm (Phaseolus vulgaris L.).

    PubMed

    de Lima, Paula Feliciano; Colombo, Carlos Augusto; Chiorato, Alisson Fernando; Yamaguchi, Lydia Fumiko; Kato, Massuo Jorge; Carbonell, Sérgio Augusto Morais

    2014-10-08

    Common bean (Phaseolus vulgaris) is present in the daily diet of various countries and, as for other legumes, has been investigated for its nutraceutical potential. Thus, 16 genotypes from different gene pools, representing seven types of seed coats and different responses to pathogens and pests, were selected to verify their isoflavone contents. The isoflavonoids daidzein and genistein and the flavonols kaempferol, myricetin, and quercetin were found. Grains of the black type showed the highest concentrations of isoflavonoids and were the only ones to exhibit daidzein. IAC Formoso, with high protein content and source of resistance to anthracnose, showed the greatest concentration of genistein, representing around 11% of the content present in soybean, as well as high levels of kaempferol. Arc 1, Raz 55, and IAC Una genotypes showed high content of coumestrol. The results suggest the use of IAC Formoso to increase the nutraceutical characteristics in common bean.

  13. The acclimation of Chlorella to high-level nitrite for potential application in biological NOx removal from industrial flue gases.

    PubMed

    Li, Tianpei; Xu, Gang; Rong, Junfeng; Chen, Hui; He, Chenliu; Giordano, Mario; Wang, Qiang

    2016-05-20

    Nitrogen oxides (NOx) are the components of fossil flue gas that give rise to the greatest environmental concerns. This study evaluated the ability of the green algae Chlorella to acclimate to high level of NOx and the potential utilization of Chlorella strains in biological NOx removal (DeNOx) from industrial flue gases. Fifteen Chlorella strains were subject to high-level of nitrite (HN, 176.5 mmolL(-1) nitrite) to simulate exposure to high NOx. These strains were subsequently divided into four groups with respect to their ability to tolerate nitrite (excellent, good, fair, and poor). One strain from each group was selected to evaluate their photosynthetic response to HN condition, and the nitrite adaptability of the four Chlorella strains were further identified by using chlorophyll fluorescence. The outcome of our experiments shows that, although high concentrations of nitrite overall negatively affect growth and photosynthesis of Chlorella strains, the degree of nitrite tolerance is a strain-specific feature. Some Chlorella strains have an appreciably higher ability to acclimate to high-level of nitrite. Acclimation is achieved through a three-step process of restrict, acclimate, and thriving. Notably, Chlorella sp. C2 was found to have a high tolerance and to rapidly acclimate to high concentrations of nitrite; it is therefore a promising candidate for microalgae-based biological NOx removal.

  14. [Isolation, Identification and Characteristic Analysis of an Oil-producing Chlorella sp. Tolerant to High-strength Anaerobic Digestion Effluent].

    PubMed

    Yang, Chuang; Wang, Wen-guo; Ma, Dan-wei; Tang, Xiao-yu; Hu, Qi-chun

    2015-07-01

    A Chlorella strain tolerant to high-strength anaerobic digestion effluent was isolated from the anaerobic digestion effluent with a long-term exposure to air. The strain was identified as a Chlorella by morphological and molecular biological methods, and named Chlorella sp. BWY-1, The anaerobic digestion effluent used in this study was from a biogas plant with the raw materials of swine wastewater after solid-liquid separation. The Chlorella regularis (FACHB-729) was used as the control strain. The comparative study showed that Chlorella sp, BWY-Ihad relatively higher growth rate, biomass accumulation capacity and pollutants removal rate in BG11. and different concentrations of anaerobic digestion effluent. Chlorella sp. BWY-1 had the highest growth rate and biomass productivity (324.40 mg.L-1) in BG11, but its lipid productivity and lipid content increased with the increase of anaerobic digestion effluent concentration, In undiluted anaerobic digestion effluent, the lipid productivity and lipid content of Chlorella sp. BWY-1 were up to 44. 43% and 108. 70 mg.L-1, respectively. Those results showed that the isolated algal strain bad some potential applications in livestock wastewater treatment and bioenergy production, it could be combined with a solid-liquid separation, anaerobic fermentation and other techniques for processing livestock wastewater and producing biodiesel.

  15. Arc spot grouping: An entanglement of arc spot cells

    SciTech Connect

    Kajita, Shin; Hwangbo, Dogyun; Ohno, Noriyasu; Tsventoukh, Mikhail M.; Barengolts, Sergey A.

    2014-12-21

    In recent experiments, clear transitions in velocity and trail width of an arc spot initiated on nanostructured tungsten were observed on the boundary of the thick and thin nanostructured layer regions. The velocity of arc spot was significantly decreased on the thick nanostructured region. It was suggested that the grouping decreased the velocity of arc spot. In this study, we try to explain the phenomena using a simple random walk model that has properties of directionality and self-avoidance. And grouping feature was added by installing an attractive force between spot cells with dealing with multi-spots. It was revealed that an entanglement of arc spot cells decreased the spot velocity, and spot cells tend to stamp at the same location many times.

  16. Psoriasiform lupus vulgaris with 30 years duration.

    PubMed

    Reich, Adam; Kobierzycka, Monika; Cisło, Maria; Schwartz, Robert A; Szepietowski, Jacek C

    2006-01-01

    Lupus vulgaris is a progressive form of cutaneous tuberculosis occurring in a person with a moderate to high degree of immunity. It is the most common type of cutaneous tuberculosis. Lupus vulgaris can be mimicked by several other skin conditions, and a 69-y-old female is described with an extremely long history of extensive infiltrative skin lesions with abundant scaling. The lesions were localized on the right arm and forearm, and on the right lateral surface of the chest. The diascopic test was positive. Moreover, a large atrophic scar was seen in the region of right cubital fossa resulting in contracture of the right elbow joint. The histopathology strongly suggested the diagnosis of tuberculosis. The final diagnosis of tuberculosis was confirmed by PCR examination. A polychemotherapeutic regimen (ethambutol 1250 mg/d, rifampicin 600 mg/d and isoniazid 300 mg/d) was successfully employed for the treatment of skin lesions.

  17. Disseminated lupus vulgaris presenting as granulomatous folliculitis.

    PubMed

    Hruza, G J; Posnick, R B; Weltman, R E

    1989-01-01

    A 69-year-old man presented with a 3-year history of scattered, grouped, asymptomatic follicular papules, pustules, and nodules tending toward coalescence into large geographic aggregates. Repeated cutaneous biopsy specimens showed granulomatous folliculitis with negative Ziehl-Neelsen stains. Finally, biopsy material submitted for mycobacterial culture grew Mycobacterium tuberculosis. No evidence of active systemic tuberculosis was found. The patient had a very rare form of tuberculosis, disseminated lupus vulgaris, presenting with granulomatous folliculitis, which is usually not seen in lupus vulgaris. The lesions resolved after an 18-month course of isoniazid and rifampin. The unusual clinical and histologic presentation as well as occasional partial remissions following a variety of nonspecific empiric therapies delayed diagnosis despite multiple evaluations. This case illustrates the importance of obtaining mycobacterial cultures from skin biopsy specimens in addition to special stains whenever cutaneous tuberculosis is suspected.

  18. Giant lupus vulgaris: A rare presentation.

    PubMed

    Sacchidanand, S; Sharavana, S; Mallikarjun, M; Nataraja, H V

    2012-01-01

    Cutaneous tuberculosis continues to be an important public health problem even with the availability of highly effective anti-tuberculous drugs. It constitutes 0.1% of all cases of extrapulmonary tuberculosis. Lupus vulgaris is the most common form of cutaneous tuberculosis that occurs in previously sensitized individuals with a moderate degree of immunity against tubercle bacilli. The different types of lupus vulgaris include plaque, ulcerative, vegetative, papular and nodular, and tumor forms. A 40-year-old man presented with large multiple plaques over right upper limb, right side of chest and back, and right lower limb for the past 30 years. Histopathology showed numerous noncaseating granulomas with Langhan's type of giant cells. The Mantoux test showed strong positivity and there was excellent response to anti-tuberculous treatment. This case is being reported because of its extreme chronicity of 30 years duration, unusually large size and multiplicity of lesions.

  19. Management of pemphigus vulgaris: challenges and solutions

    PubMed Central

    Gregoriou, Stamatis; Efthymiou, Ourania; Stefanaki, Christina; Rigopoulos, Dimitris

    2015-01-01

    The main objective in the treatment of pemphigus vulgaris is to control the disease, prevent relapses, and avoid adverse events associated with the prolonged use of steroids and immunosuppressive agents. Systemic corticosteroids remain the gold standard treatment for pemphigus vulgaris. Azathioprine and mycophenolate mofetil are the first line of steroid-sparing treatment. Rituximab is extremely effective in recalcitrant pemphigus, when other treatments fail to control the disease. The European Dermatology Forum recommends tapering prednisolone by 25% every 2 weeks after the consolidation phase, and a 5 mg reduction every 4 weeks when the dose is reduced to <20 mg. If the patient relapses, options include increasing steroids back to the previous dose, adding an immunosuppressant if using steroid monotherapy, or replacing a first-line immunosuppressant by another if already on combination therapy. PMID:26543381

  20. Pemphigus vulgaris: a rare cause of dysphagia.

    PubMed

    Al-Janabi, Ali; Greenfield, Simon

    2015-10-22

    Pemphigus vulgaris is a rare autoimmune blistering disease of the skin and mucous membranes. The case reported presented unusually with dyspepsia that was not responsive to protein pump inhibitor (PPI) therapy. This progressed to severe dysphagia and odynophagia. An esophagogastroduodenoscopy showed extensive ulceration of the esophagus, and direct immunofluorescence of an esophageal biopsy showed bright intercellular staining with C3 and IgG, confirming the diagnosis of pemphigus vulgaris. Immunological remission was achieved after a number of courses of pulsed intravenous methylprednisolone and cyclophosphamide. The patient has remained in remission for 5 years, but has required regular dilation of esophageal strictures for symptom relief. During this period, a chronic lymphocytosis was incidentally noted on routine blood tests, and chronic lymphocytic leukaemia was diagnosed. It is essential to investigate PPI-resistant symptoms, dysphagia and odynophagia, as they may indicate a serious underlying cause.

  1. Convergent evolution of the arginine deiminase pathway: the ArcD and ArcE arginine/ornithine exchangers.

    PubMed

    Noens, Elke E E; Lolkema, Juke S

    2017-02-01

    The arginine deiminase (ADI) pathway converts L-arginine into L-ornithine and yields 1 mol of ATP per mol of L-arginine consumed. The L-arginine/L-ornithine exchanger in the pathway takes up L-arginine and excretes L-ornithine from the cytoplasm. Analysis of the genomes of 1281 bacterial species revealed the presence of 124 arc gene clusters encoding the pathway. About half of the clusters contained the gene encoding the well-studied L-arginine/L-ornithine exchanger ArcD, while the other half contained a gene, termed here arcE, encoding a membrane protein that is not a homolog of ArcD. The arcE gene product of Streptococcus pneumoniae was shown to take up L-arginine and L-ornithine with affinities of 0.6 and 1 μmol/L, respectively, and to catalyze metabolic energy-independent, electroneutral exchange. ArcE of S. pneumoniae could replace ArcD in the ADI pathway of Lactococcus lactis and provided the cells with a growth advantage. In contrast to ArcD, ArcE catalyzed translocation of the pathway intermediate L-citrulline with high efficiency. A short version of the ADI pathway is proposed for L-citrulline catabolism and the presence of the evolutionary unrelated arcD and arcE genes in different organisms is discussed in the context of the evolution of the ADI pathway.

  2. Lupus vulgaris--a case report.

    PubMed

    Munn, S E; Basarab, T; Russell Jones, R

    1995-01-01

    Although lupus vulgaris is the most common form of cutaneous tuberculosis seen in Europe, the incidence has steadily declined and it is now rarely seen. We report a case in a 69-year-old lady who presented with a 10-year history of a slowly growing plaque on the left cheek. Skin biopsy confirmed caseating granulomata, and acid-fast bacilli were seen. She was commenced on triple antituberculous therapy with good effect.

  3. Clindamycin phosphate 1% gel in acne vulgaris.

    PubMed

    Rizer, R L; Sklar, J L; Whiting, D; Bucko, A; Shavin, J; Jarratt, M

    2001-01-01

    A 12-week study compared Clindagel, a unique water-based gel formulation of clindamycin phosphate 1%, administered once daily, and Cleocin T, a slightly different gel formulation indicated for twice-daily use, in the treatment of acne vulgaris. Clindagel was safe and effective and equivalent to Cleocin T gel, albeit with a better tolerability profile. Clindagel is a viable alternative to Cleocin T gel.

  4. The Psychosocial Impact of Acne Vulgaris

    PubMed Central

    Hazarika, Neirita; Archana, M

    2016-01-01

    Background: Acne vulgaris causes erythematous papulopustular lesions in active stage and often leave behind residual scarring and pigmentation. Its onset in adolescence may add to the emotional and psychological challenges experienced during this period. Aims: To assess the impact of acne on the various psychosocial domains of daily life. Materials and Methods: This was a prospective, cross-sectional study done in the dermatology out-patient department of a tertiary care hospital from January to March 2015. A total of 100 consecutive, newly diagnosed patients of acne vulgaris, aged 15 years and above were included in this study. The relationship between acne vulgaris and its sequelae was analyzed with ten different domains of daily life by using dermatology life quality index (DLQI) questionnaire. Results: Females (56%), 15–20 year olds (61%), facial lesions (60%), and Grade II acne (70%) were most common. Acne scars were noted in 75% patients, whereas 79% cases had post-acne hyperpigmentation. Thirty-seven percent patients had DLQI scores of (6–10) interpreted as moderate effect on patient's life. Statistically significant correlation (P < 0.05) found were as follows: Physical symptoms with grade of acne; embarrassment with site and grade of acne; daily activities with grade of acne and post-acne pigmentation; choice of clothes with site of acne; social activities with gender, site and grade of acne; effect on work/study with grade of acne; interpersonal problems with site and post-acne pigmentation; sexual difficulties with grade of acne. Limitation: It was a hospital-based study with small sample size. Conclusion: Significant impact of acne and its sequelae was noted on emotions, daily activities, social activities, study/work, and interpersonal relationships. Assurance and counseling along with early treatment of acne vulgaris is important to reduce disease-related psychosocial sequelae and increase the efficacy of treatment. PMID:27688440

  5. Two stage treatment of dairy effluent using immobilized Chlorella pyrenoidosa

    PubMed Central

    2013-01-01

    Background Dairy effluents contains high organic load and unscrupulous discharge of these effluents into aquatic bodies is a matter of serious concern besides deteriorating their water quality. Whilst physico-chemical treatment is the common mode of treatment, immobilized microalgae can be potentially employed to treat high organic content which offer numerous benefits along with waste water treatment. Methods A novel low cost two stage treatment was employed for the complete treatment of dairy effluent. The first stage consists of treating the diary effluent in a photobioreactor (1 L) using immobilized Chlorella pyrenoidosa while the second stage involves a two column sand bed filtration technique. Results Whilst NH4+-N was completely removed, a 98% removal of PO43--P was achieved within 96 h of two stage purification processes. The filtrate was tested for toxicity and no mortality was observed in the zebra fish which was used as a model at the end of 96 h bioassay. Moreover, a significant decrease in biological oxygen demand and chemical oxygen demand was achieved by this novel method. Also the biomass separated was tested as a biofertilizer to the rice seeds and a 30% increase in terms of length of root and shoot was observed after the addition of biomass to the rice plants. Conclusions We conclude that the two stage treatment of dairy effluent is highly effective in removal of BOD and COD besides nutrients like nitrates and phosphates. The treatment also helps in discharging treated waste water safely into the receiving water bodies since it is non toxic for aquatic life. Further, the algal biomass separated after first stage of treatment was highly capable of increasing the growth of rice plants because of nitrogen fixation ability of the green alga and offers a great potential as a biofertilizer. PMID:24355316

  6. Arc of opportunity.

    PubMed

    Delaney, Adam Vai

    2011-07-01

    Born in Port Moresby, Papua New Guinea, the author had a 20 year career in diplomacy, political affairs, and development policy analysis at the Pacific Islands Forum, the United Nations in New York; the Prime Minister's Department in Papua New Guinea (PNG) and in the Foreign Ministry of PNG. He has also been involved in theatre for over a decade in PNG, and participated in a three-month program at the Eugene O'Neill Theatre Center in Connecticut, USA. He is currently the Business Development Manager at the Torres Strait Regional Authority (Commonwealth) on Thursday Island. Since 1975 the Australian government's overseas development policy has supported various sectoral programs in its neighbouring countries, in particular Papua New Guinea and the Solomon Islands. The "creative" field has not been prominent in this strategy. While natural resources and the sports sectors have gained much greater attention, in terms of being viable international commercial enterprises, the arts, have remained stagnant. In this paper the need for joint programs genuinely supporting "wellbeing" and promoting social enterprise throughout the "arc of opportunity" is described to harness Melanesian creativity to compete successfully in world-markets, starting with penetration of the largest economy at its door-step: Australia.

  7. Percussive arc welding apparatus

    DOEpatents

    Hollar, Jr., Donald L.

    2002-01-01

    A percussive arc welding apparatus includes a generally cylindrical actuator body having front and rear end portions and defining an internal recess. The front end of the body includes an opening. A solenoid assembly is provided in the rear end portion in the internal recess of the body, and an actuator shaft assembly is provided in the front end portion in the internal recess of the actuator body. The actuator shaft assembly includes a generally cylindrical actuator block having first and second end portions, and an actuator shaft having a front end extending through the opening in the actuator body, and the rear end connected to the first end portion of the actuator block. The second end portion of the actuator block is in operational engagement with the solenoid shaft by a non-rigid connection to reduce the adverse rebound effects of the actuator shaft. A generally transversely extending pin is rigidly secured to the rear end of the shaft. One end of the pin is received in a slot in the nose housing sleeve to prevent rotation of the actuator shaft during operation of the apparatus.

  8. Accumulation of heavy metals (Cu, Cr, Pb and Cd) in freshwater micro algae (Chlorella sp.).

    PubMed

    Kumar, Rajesh M; Frankilin, J; Raj, Samuel Paul

    2013-07-01

    Some selected micro algae were used for the removal of heavy metals from wastewater. In this present investigation, Chlorella sp was studied for accumulation of heavy metals, namely copper, chromium, lead and cadmium. The salts containing heavy metals were dissolved in Blue Green 11 medium at different concentrations in a glass jar of 10 litre capacity each and subsequently they were bubbled with air for 12 days at a temperature of 33 degrees C and light intensity of 2200 lux. The removal rates of heavy metals were recorded for every 4 days during the experimental period. Chlorella sp. removed 37%, 43% and 67% of copper after 4, 8, 12 days respectively. The percentage removal of chromium was 34%, 43% and 50% respectively at 4, 8, and 12 days. Lead removal rates of Chlorella sp were 56% after 4 days, 69% after 8 days and 77% after 12 days. The reduction of cadmium in the culture medium after 12 days was 93%. From the present investigation, it is concluded that heavy metal removal ability of Chlorella sp. can be exploited for metal detoxification and environmental clean up.

  9. Production of Chlorella biomass enriched by selenium and its use in animal nutrition: a review.

    PubMed

    Doucha, Jirí; Lívanský, Karel; Kotrbácek, Václav; Zachleder, Vilém

    2009-07-01

    Feedstuffs are routinely supplemented with various selenium sources, where organic forms of Se are more bio-available and less toxic than the inorganic forms (selenites, selenates). When the algae are exposed to environmental Se in the form of selenite, they are able as other microorganisms to incorporate the element to different levels, depending on the algae species. Technology of heterotrophic fed-batch cultivation of the microalga Chlorella enriched by organically bound Se was developed, where the cultivation proceeds in fermentors on aerated and mixed nutrient solution with urea as a nitrogen and glucose as a carbon and energy source. High volumetric productivity and high cell concentrations (about 70-100 g Chlorella dry mass l(-1)) can be attained if nutrients and oxygen are adequately supplied. Addition of a small quantity of a new selenoprotein source-spray-dried Se-Chlorella biomass to the diet of farm animals had better effects on specific physiological and physical parameters of animals than selenite salt and was comparable with Se yeast added to the diet. This review introduces the importance of selenium for humans and animals, methods of Se determination, heterotrophic production of selenium-enriched Chlorella biomass in a fed-batch culture regime on organic carbon, and use of the biomass in animal nutrition.

  10. Mutate Chlorella sp. by nuclear irradiation to fix high concentrations of CO2.

    PubMed

    Cheng, Jun; Huang, Yun; Feng, Jia; Sun, Jing; Zhou, Junhu; Cen, Kefa

    2013-05-01

    To improve biomass productivity and CO2 fixation of microalgae under 15% (v/v) CO2 of flue gas, Chlorella species were mutated by nuclear irradiation and domesticated with high concentrations of CO2. The biomass yield of Chlorella pyrenoidosa mutated using 500 Gy of (60)Co γ irradiation increased by 53.1% (to 1.12 g L(-1)) under air bubbling. The mutants were domesticated with gradually increased high concentrations of CO2 [from 0.038% (v/v) to 15% (v/v)], which increased the biomass yield to 2.41 g L(-1). When light transmission and culture mixing in photo-bioreactors were enhanced at 15% (v/v) CO2, the peak growth rate of the domesticated mutant (named Chlorella PY-ZU1) was increased to 0.68 g L(-1) d(-1). When the ratio of gas flow rate (L min(-1)) to 1L of microalgae culture was 0.011, the peak CO2 fixation rate and the efficiency of Chlorella PY-ZU1 were 1.54 g L(-1) d(-1) and 32.7%, respectively.

  11. Vitmin A, nutrition, and health values of algea: spirulina, chlorella, and dunaliella

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Spirulina, chlorella, and dunalliella are unicellular algae that are commercially produced worldwide. These algae are concentrated sources of carotenoids (especially provitamin A carotenoids) and other nutrients, such as vitamin B12. Their health benefits as a complementary dietary source for macro ...

  12. PC-based arc ignition and arc length control system for gas tungsten arc welding

    SciTech Connect

    Liu, Y. ); Cook, G.E.; Barnett, R.J.; Springfield, J.F. . School of Engineering)

    1992-10-01

    In this paper, a PC-based digital control system for gas tungsten arc welding (GTAW) is presented. This system controls the arc ignition process, the arc length, and the process of welding termination. A DT2818 made by Data Translation is used for interface and A/D and D/A conversions. The digital I/O ports of the DT2818 are used for control of wirefeed, shield gas, cooling water, welding power supply, etc. The DT2818 is housed in a PC. The welding signals and status are displayed on the screen for in-process monitoring. A user can control the welding process by the keyboard.

  13. Inhibition of lentivirus replication by aqueous extracts of Prunella vulgaris

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Prunella vulgaris has been used historically in Chinese and Native American medicine. Various members of the mint family, including Prunella, have been reported to have antiviral activity. To characterize the anti-lentiviral activities of P. vulgaris, we tested water and ethanol extracts for their...

  14. Lupus vulgaris secondary to single BCG vaccination. A case report.

    PubMed

    Selimoğlu, M A; Erdem, T; Parlak, M; Eşrefoğlu, M

    1998-01-01

    A 10-year-old girl with lupus vulgaris following single BCG vaccination is reported. She had a 15 x 20 cm painless lesion covering her left shoulder, axilla, triceps and biceps region. PPD test was positive. Histopathological picture was identical to lupus vulgaris.

  15. Variation in the Breeding System of Prunella vulgaris L.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Prunella vulgaris (Lamiaceae), commonly known as selfheal, is a perennial herb with a long history of use in traditional medicine. Recent studies have found that P. vulgaris possesses anti-inflammatory, antiviral and anti-bacterial properties, which may lead to increased commercial demand. To date...

  16. Heat transfer in GTA welding arcs

    NASA Astrophysics Data System (ADS)

    Huft, Nathan J.

    Heat transfer characteristics of Gas Tungsten Arc Welding (GTAW) arcs with arc currents of 50 to 125 A and arc lengths of 3 to 11 mm were measured experimentally through wet calorimetry. The data collected were used to calculate how much heat reported to the cathode and anode and how much was lost from the arc column. A Visual Basic for Applications (VBA) macro was written to further analyze the data and account for Joule heating within the electrodes and radiation and convection losses from the arc, providing a detailed account of how heat was generated and dissipated within the system. These values were then used to calculate arc efficiencies, arc column voltages, and anode and cathode fall voltages. Trends were noted for variances in the arc column voltage, power dissipated from the arc column, and the total power dissipated by the system with changing arc length. Trends for variances in the anode and cathode fall voltages, total power dissipated, Joule heating within the torches and electrodes with changing arc current were also noted. In addition, the power distribution between the anode and cathode for each combination of arc length and arc current was examined. Keywords: Gas Tungsten Arc Welding, GTAW, anode fall, cathode fall, heat transfer, wet calorimetry

  17. Beech wood Fagus sylvatica dilute-acid hydrolysate as a feedstock to support Chlorella sorokiniana biomass, fatty acid and pigment production.

    PubMed

    Miazek, Krystian; Remacle, Claire; Richel, Aurore; Goffin, Dorothee

    2017-04-01

    This work evaluates the possibility of using beech wood (Fagus sylvatica) dilute-acid (H2SO4) hydrolysate as a feedstock for Chlorella sorokiniana growth, fatty acid and pigment production. Neutralized wood acid hydrolysate, containing organic and mineral compounds, was tested on Chlorella growth at different concentrations and compared to growth under phototrophic conditions. Chlorella growth was improved at lower loadings and inhibited at higher loadings. Based on these results, a 12% neutralized wood acid hydrolysate (Hyd12%) loading was selected to investigate its impact on Chlorella growth, fatty acid and pigment production. Hyd12% improved microalgal biomass, fatty acid and pigment productivities both in light and in dark, when compared to photoautotrophic control. Light intensity had substantial influence on fatty acid and pigment composition in Chlorella culture during Hyd12%-based growth. Moreover, heterotrophic Chlorella cultivation with Hyd12% also showed that wood hydrolysate can constitute an attractive feedstock for microalgae cultivation in case of lack of light.

  18. Dosimetric and delivery characterizations of full-arc and half-arc volumetric-modulated arc therapy for maxillary cancer.

    PubMed

    Miura, Hideharu; Fujiwara, Masayuki; Tanooka, Masao; Doi, Hiroshi; Inoue, Hiroyuki; Takada, Yasuhiro; Kamikonya, Norihiko; Hirota, Shozo

    2012-09-01

    We compared the efficiency and accuracy of full-arc and half-arc volumetric-modulated arc therapy (VMAT) delivery for maxillary cancer. Plans for gantry rotation angles of 360° and 180° (full-arc and half-arc VMAT) were created for six maxillary cancer cases with the Monaco treatment planning system, and delivered using an Elekta Synergy linear accelerator. Full-arc and half-arc VMAT were compared with regard to homogeneity index (HI), conformity index (CI), mean dose to normal brain, total monitor units (MU), delivery times, root mean square (r.m.s.) gantry accelerations (°/s(2)), and r.m.s. gantry angle errors (°). The half-arc VMAT plans achieved comparable HI and CI to the full-arc plans. Mean doses to the normal brain and brainstem with the half-arc VMAT plans were on average 16% and 17% lower than those with the full-arc VMAT plans. For other organs at risk (OARs), no significant DVH differences were observed between plans. Half-arc VMAT resulted in 11% less total MU and 20% shorter delivery time than the full-arc VMAT, while r.m.s. gantry acceleration and r.m.s. gantry angle error during half-arc VMAT delivery were 30% and 23% less than those during full-arc VMAT delivery, respectively. Furthermore, the half-arc VMAT plans were comparable with the full-arc plans regarding dose homogeneity and conformity in maxillary cancer, and provided a statistical decrease in mean dose to OAR, total MU, delivery time and gantry angle error. Half-arc VMAT plans may be a suitable treatment option in radiotherapy for maxillary cancer.

  19. High pressure neon arc lamp

    DOEpatents

    Sze, Robert C.; Bigio, Irving J.

    2003-07-15

    A high pressure neon arc lamp and method of using the same for photodynamic therapies is provided. The high pressure neon arc lamp includes a housing that encloses a quantity of neon gas pressurized to about 500 Torr to about 22,000 Torr. At each end of the housing the lamp is connected by electrodes and wires to a pulse generator. The pulse generator generates an initial pulse voltage to breakdown the impedance of the neon gas. Then the pulse generator delivers a current through the neon gas to create an electrical arc that emits light having wavelengths from about 620 nanometers to about 645 nanometers. A method for activating a photosensitizer is provided. Initially, a photosensitizer is administered to a patient and allowed time to be absorbed into target cells. Then the high pressure neon arc lamp is used to illuminate the target cells with red light having wavelengths from about 620 nanometers to about 645 nanometers. The red light activates the photosensitizers to start a chain reaction that may involve oxygen free radicals to destroy the target cells. In this manner, a high pressure neon arc lamp that is inexpensive and efficiently generates red light useful in photodynamic therapy is provided.

  20. Clines Arc through Multivariate Morphospace.

    PubMed

    Lohman, Brian K; Berner, Daniel; Bolnick, Daniel I

    2017-04-01

    Evolutionary biologists typically represent clines as spatial gradients in a univariate character (or a principal-component axis) whose mean changes as a function of location along a transect spanning an environmental gradient or ecotone. This univariate approach may obscure the multivariate nature of phenotypic evolution across a landscape. Clines might instead be plotted as a series of vectors in multidimensional morphospace, connecting sequential geographic sites. We present a model showing that clines may trace nonlinear paths that arc through morphospace rather than elongating along a single major trajectory. Arcing clines arise because different characters diverge at different rates or locations along a geographic transect. We empirically confirm that some clines arc through morphospace, using morphological data from threespine stickleback sampled along eight independent transects from lakes down their respective outlet streams. In all eight clines, successive vectors of lake-stream divergence fluctuate in direction and magnitude in trait space, rather than pointing along a single phenotypic axis. Most clines exhibit surprisingly irregular directions of divergence as one moves downstream, although a few clines exhibit more directional arcs through morphospace. Our results highlight the multivariate complexity of clines that cannot be captured with the traditional graphical framework. We discuss hypotheses regarding the causes, and implications, of such arcing multivariate clines.

  1. Addressing Free Radical Oxidation in Acne Vulgaris

    PubMed Central

    Criscito, Maressa C.; Schlesinger, Todd E.; Verdicchio, Robert; Szoke, Ernest

    2016-01-01

    Objective: Comparatively little attention has been paid to the role of free radical oxidation in acne vulgaris. Here, using the traditional abnormalities cited for acne, the authors address the role of free radical oxidation throughout the pathogenesis by detailing the chemistry that may contribute to clinical changes. To probe the effects of free radical oxidation and test an antioxidant, they conducted a preliminary study of topically applied vitamin E. Methods: Seventeen patients with mild-to-moderate acne vulgaris were evaluated over an eight-week period in two private dermatology practices in this open-label study. All patients enrolled were on the same baseline regimen of salicylic acid and benzoyl peroxide. This regimen was then supplemented with topical vitamin E in sunflower seed oil. Results: At the end of the eight-week period, all patients demonstrated clinical improvement, as indicated by a reduction in the number of lesions and global mean difference. A statistically significant reduction was noted as early as Week 2. Enrolled patients also expressed a positive experience due to good tolerability and easy application. Conclusion: Although the exact pathogenesis of acne vulgaris remains unknown, the presence of excessive reactive oxygen species can be implicated in each of the major abnormalities involved. This presence, along with the positive results of the authors’ preliminary study, demonstrates the need for more exploration on the use of topical antioxidants in limiting free radical oxidation in the acne model. This paper is designed to stimulate academic discussion regarding a new way of thinking about the disease state of acne. PMID:26962389

  2. Insulin resistance in severe acne vulgaris

    PubMed Central

    Cengiz, Fatma Pelin; Kemeriz, Funda

    2015-01-01

    Introduction Acne vulgaris is a pilosebaceous gland disease that usually affects people from puberty to young adulthood. It is seen especially on the face, neck, trunk and arms. Its severity differs from patient to patient and its pathogenesis is multifactorial. The main pathogenic factors of acne are high sebaceous gland secretion, follicular hyperproliferation, high androgen effects, propionibacterium acnes colonization and inflammation. Diet is always thought a probable reason for acne and many studies are done about acne and diet. Aim To determine the effect of insulin resistance in severe acne vulgaris. Material and methods Two hundred and forty-three acne vulgaris patients and 156 healthy controls were enrolled into the study. The blood levels of insulin and glucose were measured. Homeostasis Model Assessment (HOMA) Index was calculated. The values were compared with the control group. Results All of the patients were in the severe acne group according to their scores on the global acne scoring scale. While fasting blood glucose levels were not different between the groups (p > 0.05, 82.91 ±9.76 vs. 80.26 ±8.33), the fasting insulin levels were significantly higher in the patient group than in the control group (p < 0.001, 14.01 ±11.94 vs. 9.12 ±3.53). Additionally, there was a highly significant difference between the patient and control groups in terms of HOMA values (p < 0.001, 2.87 ±2.56 vs. 1.63 ±0.65). Conclusions These results suggest that insulin resistance may have a role in the pathogenesis of acne. PMID:26366152

  3. Disseminated lupus vulgaris: a case report.

    PubMed

    Can, Burce; Zindanci, Ilkin; Turkoglu, Zafer; Kavala, Mukaddes; Ulucay, Vasfiye; Demir, Filiz Topaloglu

    2014-01-01

    Lupus vulgaris is a secondary form of cutaneous tuberculosis which persists for years if not treated. The head and neck are the most commonly affected sites. While less frequently arms and legs, and rarely the trunk and the scalp are involved. Herein, we describe a 73-year-old man with a 5-year history of slowly growing, atrophic, some eroded and ulcerated, red-brown plaques on his forehead, nose, cheeks, ear lobes, trunk and extremites. All of his disseminated lesions healed after antituberculosis therapy.

  4. A new pyrroloquinazoline alkaloid from Linaria vulgaris.

    PubMed

    Hua, Huiming; Cheng, Maosheng; Li, Xian; Pei, Yuehu

    2002-10-01

    A new alkaloid, 1,2,3,9-tetrahydropyrrolo(2,1-b)quinazolin-1-carboxylic acid (1), together with eight known compounds, 7-hydroxy vasicine (2), benzyl alcohol beta-D-(2'-O-beta-xylopyranosyl)glucopyranoside (3), benzyl alcohol O-beta-D-glucopyranoside (4), benzyl alcohol O-beta-D-primveroside (5), 3,5-dimethyl-4-hydroxy benzaldehyde (6), gluco-syringic acid (7), syringin (8), and liriodendrin (9), were isolated from the plants of Linaria vulgaris. Their structures were established by spectroscopic methods.

  5. Pemphigus vulgaris and amyotrophic lateral sclerosis

    PubMed Central

    Mokhtari, Fatemeh; Matin, Marzieh; Rajati, Fatemeh

    2016-01-01

    Pemphigus vulgaris (PV) is an autoimmune bullous and erosive mucocutaneous disease. Rarely, it occurs in patients with other autoimmune disease. The relation between PV and neurological disorders is unclear and needs to be more studied. Here, we report a case of amyotrophic lateral sclerosis (ALS), followed by dermatologic involvement. Histopathological evidence and direct immunofluorescence are consistent with PV. Systemic corticosteroid and azathioprine were effective in the treatment of mucocutaneous lesions. PV seems to be accidentally associated with ALS. Expression of major histocompatibility complex Class II in autoimmune disease and production of autoantibodies have been proposed to describe the association of PV with ALS. PMID:28163728

  6. Pemphigus vulgaris presenting as gingival involvement.

    PubMed

    Javali, Mukhatar Ahmed; Zainab, Heena

    2012-09-01

    Pemphigus vulgaris (PV) is an autoimmune blistering disease affecting the mucous membrane and skin. Typically, oral lesions appear before skin lesions, and in a majority of the cases only oral lesions are present. The dentist may then be the first to recognize and diagnose this disease. It is unusual for PV to present over the gingiva as a primary site of involvement. Diagnosis is based on clinical presentation and confirmed by histopathological study. Early diagnosis and management can prevent the uneven life- threatening effects of this potentially chronic mucocutaneous disorder. The case serves to enhance our awareness of the gingiva as a site at which systemic disease can manifest itself.

  7. Nootropic effect of meadowsweet (Filipendula vulgaris) extracts.

    PubMed

    Shilova, I V; Suslov, N I

    2015-03-01

    The effects of the extracts of the aboveground parts of Filipendula vulgaris Moench on the behavior and memory of mice after hypoxic injury and their physical performance in the open-field test were studied using the models of hypoxia in a sealed volume, conditioned passive avoidance response (CPAR), and forced swimming with a load. The extracts improved animal resistance to hypoxia, normalized orientation and exploration activities, promoted CPAR retention after hypoxic injury, and increased physical performance. Aqueous extract of meadowsweet had the most pronounced effect that corresponded to the effect of the reference drug piracetam. These effects were probably caused by modulation of hippocampal activity.

  8. Hormonal treatment of acne vulgaris: an update

    PubMed Central

    Elsaie, Mohamed L

    2016-01-01

    Acne vulgaris is a common skin condition associated with multiple factors. Although mostly presenting alone, it can likewise present with features of hyperandrogenism and hormonal discrepancies. Of note, hormonal therapies are indicated in severe, resistant-to-treatment cases and in those with monthly flare-ups and when standard therapeutic options are inappropriate. This article serves as an update to hormonal pathogenesis of acne, discusses the basics of endocrinal evaluation for patients with suspected hormonal acne, and provides an overview of the current hormonal treatment options in women. PMID:27621661

  9. Exceptionally high heterologous protein levels in transgenic dicotyledonous seeds using Phaseolus vulgaris regulatory sequences.

    PubMed

    De Jaeger, Geert; Angenon, Geert; Depicker, Ann

    2003-01-01

    Seeds are concentrated sources of protein and thus may be ideal 'bioreactors' for the production of heterologous proteins. For this application, strong seed-specific expression signals are required. A set of expression cassettes were designed using 5' and 3' regulatory sequences of the seed storage protein gene arcelin 5-I (arc5-I) from Phaseolus vulgaris, and evaluated for the production of heterologous proteins in dicotyledonous plant species. A murine single-chain variable fragment (scFv) was chosen as model protein because of the current industrial interest to produce antibodies and derived fragments in crops. Because the highest scFv accumulation in seed had previously been achieved in the endoplasmic reticulum (ER), the scFv-encoding sequence was provided with signal sequences for accumulation in the ER. Transgenic Arabidopsis seed stocks, expressing the scFv under control of the 35S promoter, contained scFv accumulation levels in the range of 1% of total soluble protein (TSP). However, the seed storage promoter constructs boosted the scFv to exceptionally high levels. Maximum scFv levels were obtained in homozygous seed stocks, being 12.5% of TSP under control of the arc5-I regulatory sequences and even up to 36.5% of TSP upon replacing the arc5-I promoter by the beta-phaseolin promoter of Phaseolus vulgaris. Even at such very high levels, the scFv proteins retain their full antigen-binding activity. Moreover, the presence of very high scFv levels has only minory effects on seed germination and no effect on seed production. These results demonstrate that the expression levels of arcelin 5-I and beta-phaseolin seed storage protein genes can be transferred to heterologous proteins, giving exceptionally high levels of heterologous proteins, which can be of great value for the molecular farming industry by raising production yield and lowering bio-mass production and purification costs. Finally, the feasibility of heterologous protein production using the

  10. Welding arc length control system

    NASA Technical Reports Server (NTRS)

    Iceland, William F. (Inventor)

    1993-01-01

    The present invention is a welding arc length control system. The system includes, in its broadest aspects, a power source for providing welding current, a power amplification system, a motorized welding torch assembly connected to the power amplification system, a computer, and current pick up means. The computer is connected to the power amplification system for storing and processing arc weld current parameters and non-linear voltage-ampere characteristics. The current pick up means is connected to the power source and to the welding torch assembly for providing weld current data to the computer. Thus, the desired arc length is maintained as the welding current is varied during operation, maintaining consistent weld penetration.

  11. Gas Tungsten Arc Welding and Plasma Arc Cutting. Teacher Edition.

    ERIC Educational Resources Information Center

    Fortney, Clarence; And Others

    This welding curriculum guide treats two topics in detail: the care of tungsten electrodes and the entire concept of contamination control and the hafnium electrode and its importance in dual-air cutting systems that use compressed shop air for plasma arc cutting activities. The guide contains three units of instruction that cover the following…

  12. Unzipping of the volcano arc, Japan

    USGS Publications Warehouse

    Stern, R.J.; Smoot, N.C.; Rubin, M.

    1984-01-01

    A working hypothesis for the recent evolution of the southern Volcano Arc, Japan, is presented which calls upon a northward-progressing sundering of the arc in response to a northward-propagating back-arc basin extensional regime. This model appears to explain several localized and recent changes in the tectonic and magrnatic evolution of the Volcano Arc. Most important among these changes is the unusual composition of Iwo Jima volcanic rocks. This contrasts with normal arc tholeiites typical of the rest of the Izu-Volcano-Mariana and other primitive arcs in having alkaline tendencies, high concentrations of light REE and other incompatible elements, and relatively high silica contents. In spite of such fractionated characteristics, these lavas appear to be very early manifestations of a new volcanic and tectonic cycle in the southern Volcano Arc. These alkaline characteristics and indications of strong regional uplift are consistent with the recent development of an early stage of inter-arc basin rifting in the southern Volcano Arc. New bathymetric data are presented in support of this model which indicate: 1. (1) structural elements of the Mariana Trough extend north to the southern Volcano Arc. 2. (2) both the Mariana Trough and frontal arc shoal rapidly northwards as the Volcano Arc is approached. 3. (3) rugged bathymetry associated with the rifted Mariana Trough is replaced just south of Iwo Jima by the development of a huge dome (50-75 km diameter) centered around Iwo Jima. Such uplifted domes are the immediate precursors of rifts in other environments, and it appears that a similar situation may now exist in the southern Volcano Arc. The present distribution of unrifted Volcano Arc to the north and rifted Mariana Arc to the south is interpreted not as a stable tectonic configuration but as representing a tectonic "snapshot" of an arc in the process of being rifted to form a back-arc basin. ?? 1984.

  13. Total Marrow Irradiation With RapidArc Volumetric Arc Therapy

    SciTech Connect

    Aydogan, Bulent; Yeginer, Mete; Kavak, Gulbin O.; Fan, John; Radosevich, James A.; Gwe-Ya, Kim

    2011-10-01

    Purpose: To develop a volumetric arc therapy (VMAT)-total marrow irradiation (TMI) technique for patients with hematologic malignancies. Methods and Materials: VMAT planning was performed for 6 patients using RapidArc technology. The planning target volume consisted of all the bones in the body from the head to the mid-femur, excluding the extremities, except for the humerus, plus a 3.0-mm margin. The organs at risk included the lungs, heart, liver, kidneys, bowels, brain, eyes, and oral cavity. The VMAT-TMI technique consisted of three plans: the head and neck, the chest, and the pelvis, each with three 330{sup o} arcs. The plans were prescribed to ensure, at a minimum, 95% planning target volume dose coverage with the prescription dose (percentage of volume receiving dose of {>=}12 Gy was 95%). The treatments were delivered and verified using MapCheck and ion chamber measurements. Results: The VMAT-TMI technique reported in the present study provided comparable dose distributions with respect to the fixed gantry linear accelerator intensity-modulated TMI. RapidArc planning was less subjective and easier, and, most importantly, the delivery was more efficient. RapidArc reduced the treatment delivery time to approximately 18 min from 45 min with the fixed gantry linear accelerator intensity-modulated TMI. When the prescription dose coverage was reduced to 85% from 95% and the mandible and maxillary structures were not included in the planning target volume as reported in a tomotherapy study, a considerable organ at risk dose reduction of 4.2-51% was observed. The average median dose for the lungs and lenses was reduced to 5.6 Gy from 7.2 Gy and 2.4 Gy from 4.5 Gy, respectively. Conclusion: The RapidArc VMAT technique improved the treatment planning, dose conformality, and, most importantly, treatment delivery efficiency. The results from our study suggest that the RapidArc VMAT technology can be expected to facilitate the clinical transition of TMI.

  14. Lupus vulgaris: unusual presentation on face.

    PubMed

    Pilani, A; Vora, R V

    2014-01-01

    Lupus vulgaris is a variant of cutaneous tuberculosis. As the disease has potential to mutilate when left untreated, leaving deforming scars and disfigurement, an early diagnosis is of paramount importance. Though the common type is plaque type, rarely mutilating and vegetative forms also are found. A 28 year old female, labourer presented with progressive annular plaque over right side of cheek extending upto right lower lid and ala of nose. There were two satellite plaques near the right side of giant lesion. On diascopy apple jelly nodule was seen. There was no regional lymhadenopathy. Histopathological examination showed many granulomas in upper dermis extending to deep dermis comprising of epitheloid cells with langhans' type of giant cells, lymphocytic infiltration & focal necrosis suggestive of lupus vulgaris. The consequences of failing to make an early diagnosis can be disastrous for the patients, as the progression of the disease can lead to necrosis, destruction of bones and cartilage leading to permanent deformity. Thus it is vital for clinicians to have a high index of suspicion of such atypical forms and take biopsy samples for histological and bacteriological studies.

  15. [Severe eye involvement in pemphigus vulgaris].

    PubMed

    Baykal, H E; Pleyer, U; Sönnichsen, K; Thiel, H J; Zierhut, M

    1995-12-01

    Pemphigus vulgaris (PV) is an immune-mediated vesiculobullous disease of the skin and mucous membranes. Generally, patients with PV present first with oral lesions, which may precede the cutaneous lesions, such as bullae and erosions, by several months. An ocular manifestation is unusual. The most common ophthalmologic involvement in pemphigus is conjunctivitis, but without progressive scarring such as occurs in ocular cictricial pemphigoid. Corneal involvement is very rare. CASE REPORT. We report on severe ocular involvement in a 56-year-old male Turkish patient with PV. Ophthalmologic findings included conjunctival cicatrization, corneal ulceration and corneal perforation, despite immunosuppressive therapy with azathioprine and corticosteroids. A penetrating keratoplasty was performed, but rapidly failed because of corneal vascularization. CONCLUSION. If a chronic bullous dermatosis leads to severe eye involvement, PV should be considered in the differential diagnosis besides ocular cicatricial pemphigoid. Pemphigus vulgaris can be differentiated on the basis of clinical findings and histopathological and immunohistological features. Generally, PV can be treated with steroids or with a combination of an immunosuppressant and steroids. However, the combination of prednisone and azathioprine could not prevent corneal perforation in our patient.

  16. [Squamous cell carcinoma in lupus vulgaris].

    PubMed

    Kimmritz, Jens; Hermes, Barbara; Schewe, Christiane; Haas, Norbert

    2004-02-01

    Lupus vulgaris and carcinoma in lupo have become rare events that take place in the developed countries only under special circumstances. A 53-year-old woman developed such a carcinoma. She suffered from alcoholism, a well known risk factor for tuberculosis. The diagnosis of lupus vulgaris was confirmed by biopsy when an erythematous lesion on her arm that had been present for 25 years enlarged and subsequently ulcerated. Chemotherapy was discontinued because of lack of compliance and the ulcer grew markedly over the following 16 months. Therefore the entire lesion was excised. Histology showed a squamous cell carcinoma within the ulcer. Neither further systemic manifestations of tuberculosis nor metastases of the carcinoma were found. Under continuous combined antituberculous therapy, the patient remained free of symptoms. This case underlines the problems associated with a disease that has been nearly forgotten in the western countries. It also shows that alcoholism is a risk factor for tuberculosis, along with debilitating diseases such as lymphoma and AIDS as well as immunosuppressive therapy.

  17. [Microstructural changes in hardened beans (Phaseolus vulgaris)].

    PubMed

    Mujica, Maria Virginia; Granito, Marisela; Soto, Naudy

    2015-06-01

    (Phaseolus vulgaris). The hardening of Phaseolus vulgaris beans stored at high temperature and high relative humidity is one of the main constraints for consumption. The objective of this research was to evaluate by scanning electron microscopy, structural changes in cotyledons and testa of the hardened beans. The freshly harvested grains were stored for twelve months under two conditions: 5 ° C-34% RH and 37 ° C-75% RH, in order to promote hardening. The stored raw and cooked grains were lyophilized and fractured. The sections of testa and cotyledons were observed in an electron microscope JSM-6390. After twelve months, grains stored at 37 ° C-75% RH increased their hardness by 503%, whereas there were no significant changes in grains stored at 5 ° C-34% RH. At the microstructural level, the cotyledons of the raw grains show clear differences in appearance of the cell wall, into the intercellular space size and texture matrix protein. There were also differences in compaction of palisade and sub-epidermal layer in the testa of raw grains. After cooking, cotyledon cells of the soft grains were well separated while these ofhard grains were seldom separated. In conclusion, the found differences in hard and soft grains showed a significant participation of both structures, cotyledons and testa, in the grains hardening.

  18. Oxidative Stress in Patients With Acne Vulgaris

    PubMed Central

    Arican, Ozer; Belge Kurutas, Ergul; Sasmaz, Sezai

    2005-01-01

    Acne vulgaris is one of the common dermatological diseases and its pathogenesis is multifactorial. In this study, we aim to determine the effects of oxidative stress in acne vulgaris. Forty-three consecutive acne patients and 46 controls were enrolled. The parameters of oxidative stress such as catalase (CAT), glucose-6-phosphate dehydrogenase (G6PD), superoxide dismutase (SOD), and malondialdehyde (MDA) in the venous blood of cases were measured spectrophotometrically. The values compared with control group, the relation between the severity and distribution of acne, and the correlation of each enzyme level were researched. CAT and G6PD levels in patients were found to be statistically decreased, and SOD and MDA levels were found to be statistically increased (P < .001). However, any statistical difference and correlation could not be found between the severity and distribution of lesions and the mean levels of enzymes. In addition, we found that each enzyme is correlated with one another. Our findings show that oxidative stress exists in the acne patients. It will be useful to apply at least one antioxidant featured drug along with the combined acne treatment. PMID:16489259

  19. Role of olfaction in Octopus vulgaris reproduction.

    PubMed

    Polese, Gianluca; Bertapelle, Carla; Di Cosmo, Anna

    2015-01-01

    The olfactory system in any animal is the primary sensory system that responds to chemical stimuli emanating from a distant source. In aquatic animals "Odours" are molecules in solution that guide them to locate food, partners, nesting sites, and dangers to avoid. Fish, crustaceans and aquatic molluscs possess sensory systems that have anatomical similarities to the olfactory systems of land-based animals. Molluscs are a large group of aquatic and terrestrial animals that rely heavily on chemical communication with a generally dispersed sense of touch and chemical sensitivity. Cephalopods, the smallest class among extant marine molluscs, are predators with high visual capability and well developed vestibular, auditory, and tactile systems. Nevertheless they possess a well developed olfactory organ, but to date almost nothing is known about the mechanisms, functions and modulation of this chemosensory structure in octopods. Cephalopod brains are the largest of all invertebrate brains and across molluscs show the highest degree of centralization. The reproductive behaviour of Octopus vulgaris is under the control of a complex set of signal molecules such as neuropeptides, neurotransmitters and sex steroids that guide the behaviour from the level of individuals in evaluating mates, to stimulating or deterring copulation, to sperm-egg chemical signalling that promotes fertilization. These signals are intercepted by the olfactory organs and integrated in the olfactory lobes in the central nervous system. In this context we propose a model in which the olfactory organ and the olfactory lobe of O. vulgaris could represent the on-off switch between food intake and reproduction.

  20. Effects of trifluoromethyl ketones on the motility of Proteus vulgaris.

    PubMed

    Wolfart, Krisztina; Molnar, Annamaria; Kawase, Masami; Motohashi, Noboru; Molnar, Joseph

    2004-09-01

    In the present study, we showed the inhibition of motility by trifluoromethyl ketone (TF) derivatives (1-8) in Proteus vulgaris (P. vulgaris) cultures. Among them, 1-(2-benzoxazoyl)-3,3,3-trifluoro-2-propanone (1) showed a much stronger inhibitory effect on the motility of P. vulgaris than other TF compounds at 10% MIC. Our results suggest the possibility of an inhibitory action of TF compounds on the proton motive forces by affecting the action of biological motor and proton efflux in the membranes, resulting in a reduction of the ratio of running and the increased number of tumbling and non-motile cells.

  1. Biomass and lipid production of a local isolate Chlorella sorokiniana under mixotrophic growth conditions.

    PubMed

    Juntila, D J; Bautista, M A; Monotilla, W

    2015-09-01

    A local Chlorella sp. isolate with 97% rbcL sequence identity to Chlorella sorokiniana was evaluated in terms of its biomass and lipid production under mixotrophic growth conditions. Glucose-supplemented cultures exhibited increasing growth rate and biomass yield with increasing glucose concentration. Highest growth rate and biomass yield of 1.602 day(-1) and 687.5 mg L(-1), respectively, were achieved under 2 g L(-1) glucose. Nitrogen starvation up to 75% in the 1.0 g L(-1) glucose-supplemented culture was done to induce lipid accumulation and did not significantly affect the growth. Lipid content ranges from 20% to 27% dry weight. Nile Red staining showed more prominent neutral lipid bodies in starved mixotrophic cultures. C. sorokiniana exhibited enhanced biomass production under mixotrophy and more prominent neutral lipid accumulation under nitrogen starvation with no significant decrease in growth; hence, this isolate could be further studied to establish its potential for biodiesel production.

  2. Spirulina platensis is more efficient than Chlorella homosphaera in carbohydrate productivity.

    PubMed

    Margarites, Ana Cláudia; Volpato, Noany; Araújo, Elenara; Cardoso, Luana Garbin; Bertolin, Telma Elita; Colla, Luciane Maria; Costa, Jorge Alberto Vieira

    2016-11-21

    This study aimed to compare the production of biomass with high carbohydrate content by Spirulina platensis LEB 52 and Chlorella homosphaera microalgae. The cultivation of C. homosphaera and S. platensis LEB 52 was performed in standard medium diluted at 50%, and glucose was added as a source of organic carbon for mixotrophic metabolism. The sodium nitrate concentration was increased and the nitrogen components were reduced in the media to induce the synthesis of carbohydrates. C. homosphaera and S. platensis LEB 52 produced 16.32 and 116 mg L(-1) of carbohydrates per day, respectively, when cultivated with 50% less nitrogen and 20% and 10% more sodium chloride, compared with the control. Glucose addition was an essential factor for microalgal growth, resulting in biomass increases of up to 2.79- and 3.45-fold for C. homosphaera and S. platensis LEB 52, respectively. Spirulina presented better characteristics than Chlorella with regard to the capacities of growth and carbohydrate synthesis.

  3. Nitrogen balancing and xylose addition enhances growth capacity and protein content in Chlorella minutissima cultures.

    PubMed

    Freitas, B C B; Esquível, M G; Matos, R G; Arraiano, C M; Morais, M G; Costa, J A V

    2016-10-01

    This study aimed to examine the metabolic changes in Chlorella minutissima cells grown under nitrogen-deficient conditions and with the addition of xylose. The cell density, maximum photochemical efficiency, and chlorophyll and lipid levels were measured. The expression of two photosynthetic proteins, ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) and the beta subunit (AtpB) of adenosine triphosphate synthase, were measured. Comparison of cells grown in medium with a 50% reduction in the nitrogen concentration versus the traditional medium solution revealed that the cells grown under nitrogen-deficient conditions exhibited an increased growth rate, higher maximum cell density (12.7×10(6)cellsmL(-1)), optimal PSII efficiency (0.69) and decreased lipid level (25.08%). This study has taken the first steps toward protein detection in Chlorella minutissima, and the results can be used to optimize the culturing of other microalgae.

  4. Virus infection of Chlorella variabilis and enzymatic saccharification of algal biomass for bioethanol production.

    PubMed

    Cheng, Yu-Shen; Zheng, Yi; Labavitch, John M; VanderGheynst, Jean S

    2013-06-01

    Experiments were conducted to investigate the application of virus infection and amylolytic enzyme treatment on sugar release from Chlorella variabilis NC64A and bioethanol production from released sugars via Escherichia coli KO11 fermentation. Chlorella variabilis NC64A accumulated starch when it was cultured in a nitrogen-limited medium. The accumulated starch was not consumed during viral infection based on analysis of sugars released during infection. Both amylolytic enzyme addition and virus infection increased the hydrolysis of carbohydrates. Addition of amylolytic enzymes increased the release of glucose from algal biomass while virus addition increased the release of non-glucose neutral sugars. The combination of enzyme addition and virus infection also resulted in the highest ethanol production after fermentation. Acetic acid was generated as a co-product during fermentation in all sets of experiments. This study demonstrated that infection of microalgae with an algal virus resulted in disruption and hydrolysis of algal biomass to generate fermentable sugars.

  5. Enhanced lipid production in thermo-tolerant mutants of Chlorella pyrenoidosa NCIM 2738.

    PubMed

    Sachdeva, Neha; Gupta, Ravi Prakash; Mathur, Anshu Shankar; Tuli, Deepak Kumar

    2016-12-01

    The present study aimed to develop thermo-tolerant mutants of Chlorella pyrenoidosa NCIM 2738 for high lipids production. For this, ethyl methane sulfonate was used, which generated two effective thermo-tolerant mutants, M18 and M24 of Chlorella pyrenoidosa NCIM 2738, capable of surviving at temperature up to 47°C and showing improved lipid and biomass yields. They showed 59.62% and 50.75% increase, respectively in lipid content compared to wild type at 30°C, which could not grow at temperature above 35°C. The novelty of this study lied in incorporation of PAM Flurometry with mutagenesis to generate thermo-tolerant mutants of C. pyrenoidosa and investigating the reasons for increased yields of mutants at cellular and photosynthetic levels with the aim to use them for commercial biodiesel production.

  6. Arc-textured high emittance radiator surfaces

    NASA Technical Reports Server (NTRS)

    Banks, Bruce A. (Inventor)

    1991-01-01

    High emittance radiator surfaces are produced by arc-texturing. This process produces such a surface on a metal by scanning it with a low voltage electric arc from a carbon electrode in an inert environment.

  7. Physicochemical effects on sulfite transformation in a lipid-rich Chlorella sp. strain

    NASA Astrophysics Data System (ADS)

    Liang, Fang; Wen, Xiaobin; Luo, Liming; Geng, Yahong; Li, Yeguang

    2014-11-01

    SO2 is very rapidly hydrated to sulfurous acid in water solution at pH value above 6.0, whereby sulfite is yielded from the disassociation of protons. We aimed to improve the sulfite transformation efficiency and provide a basis for the direct utilization of SO2 from flue gas by a microalgal suspension. Chlorella sp. XQ-20044 was cultured in a medium with 20 mmol/L sodium sulfite under different physicochemical conditions. Under light conditions, sulfite concentration in the algal suspension reduced linearly over time, and was completely converted into sulfate within 8 h. The highest sulfite transformation rate (3.25 mmol/(L·h)) was obtained under the following conditions: 35°C, light intensity of 300 μmol/(m2·s), NaHCO3 concentration of 6 g/L, initial cell density (OD540) of 0.8 and pH of 9-10. There was a positive correlation between sulfite transformation rate and the growth of Chlorella, with the conditions favorable to algal growth giving better sulfite transformation. Although oxygen in the air plays a role in the transformation of SO2- 3 to SO2- 4, the transformation is mainly dependent on the metabolic activity of algal cells. Chlorella sp. XQ-20044 is capable of tolerating high sulfite concentration, and can utilize sulfite as the sole sulfur source for maintaining healthy growth. We found that sulfite ≤20 mmol/L had no obvious effect on the total lipid content and fatty acid profiles of the algae. Thus, the results suggest it is feasible to use flue gas for the mass production of feedstock for biodiesel using Chlorella sp. XQ-20044, without preliminary removal of SO2, assuming there is adequate control of the pH.

  8. Production of deuterated lutein by Chlorella protothecoides and its detection by mass spectrometric methods.

    PubMed

    Bhosale, Prakash; Serban, Bogdan; Bernstein, Paul S

    2006-09-01

    Chlorella protothecoides, a lutein-producing microalga, was grown aerobically in a mineral medium prepared with 70% (v/v) deuterated water. HPLC/atmospheric pressure chemical ionization-mass spectrometry (HPLC/APCI-MS) analysis revealed approximately 58% replacement of hydrogen by deuterium atoms as indicated by the molecular mass cluster at around m/z 599. The rapidly growing microalga had much higher levels (58%) of deuterium substitution relative to previously reported (9-15%) natural sources of lutein.

  9. Warm storage for arc magmas

    NASA Astrophysics Data System (ADS)

    Barboni, Mélanie; Boehnke, Patrick; Schmitt, Axel K.; Harrison, T. Mark; Shane, Phil; Bouvier, Anne-Sophie; Baumgartner, Lukas

    2016-12-01

    Felsic magmatic systems represent the vast majority of volcanic activity that poses a threat to human life. The tempo and magnitude of these eruptions depends on the physical conditions under which magmas are retained within the crust. Recently the case has been made that volcanic reservoirs are rarely molten and only capable of eruption for durations as brief as 1,000 years following magma recharge. If the “cold storage” model is generally applicable, then geophysical detection of melt beneath volcanoes is likely a sign of imminent eruption. However, some arc volcanic centers have been active for tens of thousands of years and show evidence for the continual presence of melt. To address this seeming paradox, zircon geochronology and geochemistry from both the frozen lava and the cogenetic enclaves they host from the Soufrière Volcanic Center (SVC), a long-lived volcanic complex in the Lesser Antilles arc, were integrated to track the preeruptive thermal and chemical history of the magma reservoir. Our results show that the SVC reservoir was likely eruptible for periods of several tens of thousands of years or more with punctuated eruptions during these periods. These conclusions are consistent with results from other arc volcanic reservoirs and suggest that arc magmas are generally stored warm. Thus, the presence of intracrustal melt alone is insufficient as an indicator of imminent eruption, but instead represents the normal state of magma storage underneath dormant volcanoes.

  10. Metal vapor arc ion plating

    DOEpatents

    Bertram, L.A.; Fisher, R.W.; Mattox, D.M.; Zanner, F.J.

    1986-09-09

    A method and apparatus for ion plating are described. The apparatus uses more negative than a first electrode voltage in a vacuum arc remelt system to attract low energy ions from the anode electrode to the article to be plated. 2 figs.

  11. Warm storage for arc magmas.

    PubMed

    Barboni, Mélanie; Boehnke, Patrick; Schmitt, Axel K; Harrison, T Mark; Shane, Phil; Bouvier, Anne-Sophie; Baumgartner, Lukas

    2016-12-06

    Felsic magmatic systems represent the vast majority of volcanic activity that poses a threat to human life. The tempo and magnitude of these eruptions depends on the physical conditions under which magmas are retained within the crust. Recently the case has been made that volcanic reservoirs are rarely molten and only capable of eruption for durations as brief as 1,000 years following magma recharge. If the "cold storage" model is generally applicable, then geophysical detection of melt beneath volcanoes is likely a sign of imminent eruption. However, some arc volcanic centers have been active for tens of thousands of years and show evidence for the continual presence of melt. To address this seeming paradox, zircon geochronology and geochemistry from both the frozen lava and the cogenetic enclaves they host from the Soufrière Volcanic Center (SVC), a long-lived volcanic complex in the Lesser Antilles arc, were integrated to track the preeruptive thermal and chemical history of the magma reservoir. Our results show that the SVC reservoir was likely eruptible for periods of several tens of thousands of years or more with punctuated eruptions during these periods. These conclusions are consistent with results from other arc volcanic reservoirs and suggest that arc magmas are generally stored warm. Thus, the presence of intracrustal melt alone is insufficient as an indicator of imminent eruption, but instead represents the normal state of magma storage underneath dormant volcanoes.

  12. Vacuum Gas Tungsten Arc Welding

    NASA Technical Reports Server (NTRS)

    Weeks, J. L.; Todd, D. T.; Wooten, J. R.

    1997-01-01

    A two-year program investigated vacuum gas tungsten arc welding (VGTAW) as a method to modify or improve the weldability of normally difficult-to-weld materials. After a vacuum chamber and GTAW power supply were modified, several difficult-to-weld materials were studied and key parameters developed. Finally, Incoloy 903 weld overlays were produced without microfissures.

  13. STRUVE arc and EUPOS® stations

    NASA Astrophysics Data System (ADS)

    Lasmane, Ieva; Kaminskis, Janis; Balodis, Janis; Haritonova, Diana

    2013-04-01

    The Struve Geodetic Arc was developed in Years 1816 to 1855, 200 years ago. Historic information on the points of the Struve Geodetic Arc are included in the UNESCO World Heritage list in 2005. Nevertheless, the sites of many points are still not identified nor included in the data bases nowadays. Originally STRUVE arc consisted of 258 main triangles with 265 triangulation points. Currently 34 of the original station points are identified and included in the in the UNESCO World Heritage list. identified original measurement points of the Meridian Arc are located in Sweden (7 points), Norway (15), Finland (83), Russia (1), Estonia (22), Latvia (16), Lithuania (18), Belorussia (28), Ukraine (59) and Moldova (27). In Year 2002 was initiated another large coverage project - European Position Determination System "EUPOS®". Currently there are about 400 continuously operating GNSS (Global Navigation Satellite Systems) stations covering EU countries Estonia, Latvia, Lithuania, Poland, Czech Republic, Slovakia, Hungary, Bulgaria, Romania and East European countries Ukraine and Moldavia. EUPOS® network is a ground based GNSS augmentation system widely used for geodesy, land surveying, geophysics and navigation. It gives the opportunity for fast and accurate position determination never available before. It is an honorable task to use the EUPOS® system for research of the Struve triangulation former sites. Projects with Struve arc can popularize geodesy, geo-information and its meaning in nowadays GIS and GNSS systems. Struve Arc and its points is unique cooperation cross-border object which deserve special attention because of their natural beauty and historical value for mankind. GNSS in geodesy discovers a powerful tool for the verification and validation of the height values of geodetic leveling benchmarks established historically almost 200 years ago. The differential GNSS and RTK methods appear very useful to identify vertical displacement of landscape by means of

  14. Large-scale biodiesel production from microalga Chlorella protothecoides through heterotrophic cultivation in bioreactors.

    PubMed

    Li, Xiufeng; Xu, Han; Wu, Qingyu

    2007-11-01

    An integrated approach of biodiesel production from heterotrophic Chlorella protothecoides focused on scaling up fermentation in bioreactors was reported in this study. Through substrate feeding and fermentation process controls, the cell density of C. protothecoides achieved 15.5 g L(-1) in 5 L, 12.8 g L(-1) in 750 L, and 14.2 g L(-1) in 11,000 L bioreactors, respectively. Resulted from heterotrophic metabolism, the lipid content reached 46.1%, 48.7%, and 44.3% of cell dry weight in samples from 5 L, 750 L, and 11,000 L bioreactors, respectively. Transesterification of the microalgal oil was catalyzed by immobilized lipase from Candidia sp. 99-125. With 75% lipase (12,000 U g(-1), based on lipid quantity) and 3:1 molar ratio of methanol to oil batch-fed at three times, 98.15% of the oil was converted to monoalkyl esters of fatty acids in 12 h. The expanded biodiesel production rates were 7.02 g L(-1), 6.12 g L(-1), and 6.24 g L(-1) in 5 L, 750 L, and 11,000 L bioreactors, respectively. The properties of biodiesel from Chlorella were comparable to conventional diesel fuel and comply with the US Standard for Biodiesel (ASTM 6751). These results suggest that it is feasible to expand heterotrophic Chlorella fermentation for biodiesel production at the industry level.

  15. Zepp, a LINE-like retrotransposon accumulated in the Chlorella telomeric region.

    PubMed Central

    Higashiyama, T; Noutoshi, Y; Fujie, M; Yamada, T

    1997-01-01

    Six copies of insertion elements accumulate in the subtelomeric region immediately proximal to the telomeric repeats on Chlorella chromosome I. The elements, designated Zepps, bear the characteristic features of non-viral (LINE-like) retrotransposons, including a poly(A) tail, 5'-truncations, a retroviral reverse transcriptase-like ORF and flanking target duplications. Detailed sequence analysis of the Chlorella subtelomeric region revealed a novel mechanism of Zepp transposition; successive insertions of each Zepp element into another Zepp as a target, leaving a tandem array of their 3'-regions with poly(A) tracts facing toward the centromere. Only the most distal Zepp copy was inverted to connect its poly(A) tail with the telomeric repeats. A similar Zepp cluster but without the telomeric repeats was also found at the terminus of another Chlorella chromosome. These structures contrast with that proposed for the addition of HeT-A and TART elements to Drosophila telomeres. Expression of Zepp elements is induced by heat shock treatment. Possible roles of the subtelomeric retrotransposons in formation and maintenance of telomeres are discussed. PMID:9218812

  16. Cultivation of Chlorella on brewery wastewater and nano-particle biosynthesis by its biomass.

    PubMed

    Subramaniyam, Vidhyasri; Subashchandrabose, Suresh Ramraj; Ganeshkumar, Vimalkumar; Thavamani, Palanisami; Chen, Zuliang; Naidu, Ravi; Megharaj, Mallavarapu

    2016-07-01

    This study investigated an integrated and sustainable approach for iron nanoparticles synthesis using Chlorella sp. MM3 biomass produced from the remediation of brewery wastewater. The algal growth characteristics, biomass production, nutrient removal, and nanoparticle synthesis including its characterisation were studied to prove the above approach. The growth curve of Chlorella depicted lag and exponential phase characteristics during the first 4days in a brewery wastewater collected from a single batch of brewing process (single water sample) indicating the growth of algae in brewery wastewater. The pollutants such as total nitrogen, total phosphorus and total organic carbon in single water sample were completely utilised by Chlorella for its growth. The X-ray photoelectron spectroscopy spectra showed peaks at 706.56eV, 727.02eV, 289.84eV and 535.73eV which corresponded to the zero-valent iron, iron oxides, carbon and oxygen respectively, confirming the formation of iron nanoparticle capped with algal biomolecules. Scanning electron microscopy and particle size analysis confirmed the presence of spherical shaped iron nanoparticles of size ranging from 5 to 50nm. To our knowledge, this is the first report on nanoparticle synthesis using the biomass generated from phycoremediation of brewery wastewater.

  17. Laboratory experiments on arc deflection and instability

    SciTech Connect

    Zweben, S.; Karasik, M.

    2000-03-21

    This article describes experiments on arc deflection instability carried out during the past few years at the Princeton University Plasma Physics Laboratory (PPPL). The approach has been that of plasma physicists interested in arcs, but they believe these results may be useful to engineers who are responsible for controlling arc behavior in large electric steel furnaces.

  18. Magnification Bias in Gravitational Arc Statistics

    SciTech Connect

    Caminha, G. B.; Estrada, J.; Makler, M.

    2013-08-29

    The statistics of gravitational arcs in galaxy clusters is a powerful probe of cluster structure and may provide complementary cosmological constraints. Despite recent progresses, discrepancies still remain among modelling and observations of arc abundance, specially regarding the redshift distribution of strong lensing clusters. Besides, fast "semi-analytic" methods still have to incorporate the success obtained with simulations. In this paper we discuss the contribution of the magnification in gravitational arc statistics. Although lensing conserves surface brightness, the magnification increases the signal-to-noise ratio of the arcs, enhancing their detectability. We present an approach to include this and other observational effects in semi-analytic calculations for arc statistics. The cross section for arc formation ({\\sigma}) is computed through a semi-analytic method based on the ratio of the eigenvalues of the magnification tensor. Using this approach we obtained the scaling of {\\sigma} with respect to the magnification, and other parameters, allowing for a fast computation of the cross section. We apply this method to evaluate the expected number of arcs per cluster using an elliptical Navarro--Frenk--White matter distribution. Our results show that the magnification has a strong effect on the arc abundance, enhancing the fraction of arcs, moving the peak of the arc fraction to higher redshifts, and softening its decrease at high redshifts. We argue that the effect of magnification should be included in arc statistics modelling and that it could help to reconcile arcs statistics predictions with the observational data.

  19. Making Conductive Polymers By Arc Tracking

    NASA Technical Reports Server (NTRS)

    Daech, Alfred F.

    1992-01-01

    Experimental technique for fabrication of electrically conductive polymeric filaments based on arc tracking, in which electrical arc creates conductive carbon track in material that initially was insulator. Electrically conductive polymeric structures made by arc tracking aligned along wire on which formed. Alignment particularly suited to high conductivity and desirable in materials intended for testing as candidate superconductors.

  20. Arc-starting aid for GTA welding

    NASA Technical Reports Server (NTRS)

    Whiffen, E. L.

    1977-01-01

    Three-in-one handtool combining arc-gap gage, electrode tip sander, and electrode projection gate, effectively improves initiation on gas tungsten arc (GTA), automatic skate-welding machines. Device effects ease in polishing electrode tips and setting exactly initial arc gap before each weld pass.

  1. Thermal analysis of an arc heater electrode with a rotating arc foot

    NASA Technical Reports Server (NTRS)

    Milos, Frank S.; Shepard, Charles E.

    1993-01-01

    A smoothly rotating arc foot and an arc foot that jumps between multiple sticking points were analyzed using analytic formulations and numerical solution procedures. For each case the temperature distribution for a copper electrode was obtained for the plausible range of operating conditions. It is shown that the smoothly rotating arc foot is an extremely safe mode of operation, whereas the jumping arc foot produces excessively high electrode surface temperatures which are not greatly alleviated by increasing the average rotational frequency of the arc foot. It is suggested to eliminate arc-foot rotation and rely on the distribution of fixed electrodes with stationary arc attachment to avoid electrode failure at high current.

  2. Plant Anticancer Agents XXXIII. Constituents of Passerina vulgaris1.

    PubMed

    Ji-Xian, G; Handa, S S; Pezzuto, J M; Kinghorn, A D; Farnsworth, N R

    1984-06-01

    Two lignans of known structure, (+)-syringaresinol, a cytotoxic agent, and (+)-nortrachelogenin, a compound with demonstrated antileukemic activity, were isolated from a biologically active extract of the stems of PASSERINA VULGARIS.

  3. Propionibacterium acnes in the pathogenesis and immunotherapy of acne vulgaris.

    PubMed

    Liu, Pei-Feng; Hsieh, Yao-Dung; Lin, Ya-Ching; Two, Aimee; Shu, Chih-Wen; Huang, Chun-Ming

    2015-01-01

    Acne vulgaris, a multi-factorial disease, is one of the most common skin diseases, affecting an estimated 80% of Americans at some point during their lives. The gram-positive and anaerobic Propionibacterium acnes (P. acnes) bacterium has been implicated in acne inflammation and pathogenesis. Therapies for acne vulgaris using antibiotics generally lack bacterial specificity, promote the generation of antibiotic-resistant bacterial strains, and cause adverse effects. Immunotherapy against P. acnes or its antigens (sialidase and CAMP factor) has been demonstrated to be effective in mice, attenuating P. acnes-induced inflammation; thus, this method may be applied to develop a potential vaccine targeting P. acnes for acne vulgaris treatment. This review summarizes reports describing the role of P. acnes in the pathogenesis of acne and various immunotherapy-based approaches targeting P. acnes, suggesting the potential effectiveness of immunotherapy for acne vulgaris as well as P. acnes-associated diseases.

  4. Effect of light intensity on algal biomass accumulation and biodiesel production for mixotrophic strains Chlorella kessleri and Chlorella protothecoide cultivated in highly concentrated municipal wastewater.

    PubMed

    Li, Yecong; Zhou, Wenguang; Hu, Bing; Min, Min; Chen, Paul; Ruan, Roger R

    2012-09-01

    In this research, the effect of light intensity on biomass accumulation, wastewater nutrient removal through algae cultivation, and biodiesel productivity was investigated with algae species Chlorella kessleri and Chlorella protothecoide. The light intensities studied were 0, 15, 30, 60, 120, and 200 µmol m(-2) s(-1). The results showed that light intensity had profound impact on tested responses for both strains, and the dependence of these responses on light intensity varied with different algae strains. For C. kessleri, the optimum light intensity was 120 µmol m(-2) S(-1) for all responses except for COD removal. For C. protothecoide, the optimum light intensity was 30 µmol m(-2) S(-1). The major components of the biodiesel produced from algae biomass were 16-C and 18-C FAME, and the highest biodiesel contents were 24.19% and 19.48% of dried biomass for C. kessleri and C. protothecoide, respectively. Both species were capable of wastewater nutrients removal under all lighting conditions with high removal efficiencies.

  5. Lupus vulgaris of external nose--a case report.

    PubMed

    Arunkumar, J S; Naveen, K N; Prasad, K C; Santhosh, S G; Hegde, J S

    2013-02-01

    Lupus vulgaris is the most common morphological variant of cutaneous tuberculosis accounting for approximately 59% of cases of cutaneous tuberculosis in India. We present a case of lupus vulgaris of external nose diagnosed early and treated with CAT-3 RNTCP regimen for six months without any nasal deformity except for a small scar over the dorsum of the nose. Patient followed up for one year after completion of the prescribed regimen, there being no recurrence of the lesion.

  6. Uropathogenic properties of Proteus mirabilis and Proteus vulgaris.

    PubMed

    Peerbooms, P G; Verweij, A M; MacLaren, D M

    1985-02-01

    A group of faecal isolates of Proteus vulgaris and P. mirabilis was studied for the presence of possible virulence factors such as growth rates in urine and broth, haemolysin production, hydrophobicity, sensitivity to the bactericidal activity of human serum and cell invasiveness. Differences were found in haemolysin production, cell invasiveness and experimental virulence in a mouse model. These differences might explain why P. mirabilis is much more common in human urinary-tract infections than P. vulgaris.

  7. [Squamous epithelial carcinoma as a complication of lupus vulgaris].

    PubMed

    Betti, R; Tolomio, E; Vergani, R; Crosti, C

    2002-02-01

    Lupus vulgaris represents a type of cutaneous tuberculosis that, if not correctly treated, presents a progressive chronic development whose long-term complications include cutaneous neoplasms. We report on a 55-year-old man presenting a 10-year-old ulcerated and bleeding lupus vulgaris lesion on the left cheek containing a squamous cell carcinoma. Reviewing the literature, we search for possible causes of delay in diagnosis that even now allowed therapy only after discovery of the tumoral complication.

  8. Analysis of Autophagy Genes in Microalgae: Chlorella as a Potential Model to Study Mechanism of Autophagy

    PubMed Central

    Jiang, Qiao; Zhao, Li; Dai, Junbiao; Wu, Qingyu

    2012-01-01

    Background Microalgae, with the ability to mitigate CO2 emission and produce carbohydrates and lipids, are considered one of the most promising resources for producing bioenergy. Recently, we discovered that autophagy plays a critical role in the metabolism of photosynthetic system and lipids production. So far, more than 30-autophagy related (ATG) genes in all subtypes of autophagy have been identified. However, compared with yeast and mammals, in silico and experimental research of autophagy pathways in microalgae remained limited and fragmentary. Principal Findings In this article, we performed a genome-wide analysis of ATG genes in 7 microalgae species and explored their distributions, domain structures and evolution. Eighteen “core autophagy machinery” proteins, four mammalian-specific ATG proteins and more than 30 additional proteins (including “receptor-adaptor” complexes) in all subtypes of autophagy were analyzed. Data revealed that receptor proteins in cytoplasm-to-vacuole targeting and mitophagy seem to be absent in microalgae. However, most of the “core autophagy machinery” and mammalian-specific proteins are conserved among microalgae, except for the ATG9-cycling system in Chlamydomonas reinhardtii and the second ubiquitin-like protein conjugation complex in several algal species. The catalytic and binding residues in ATG3, ATG5, ATG7, ATG8, ATG10 and ATG12 are also conserved and the phylogenetic tree of ATG8 coincides well with the phylogenies. Chlorella contains the entire set of the core autophagy machinery. In addition, RT-PCR analysis verified that all crucial ATG genes tested are expressed during autophagy in both Chlorella and Chlamydomonas reinhardtii. Finally, we discovered that addition of 3-Methyladenine (a PI3K specific inhibitor) could suppress the formation of autophagic vacuoles in Chlorella. Conclusions Taken together, Chlorella may represent a potential model organism to investigate autophagy pathways in photosynthetic

  9. ION PRODUCING MECHANISM (ARC EXTERNAL TO BLOCK)

    DOEpatents

    Brobeck, W.H.

    1958-09-01

    This patent pentains to an ion producing mechanism employed in a calutron which has the decided advantage of an increased amount of ionization effectuated by the arc, and a substantially uniform arc in poiat of time, i arc location and along the arc length. The unique features of the disclosed ion source lie in the specific structural arrangement of the source block, gas ionizing passage, filament shield and filament whereby the arc is established both within the ionizing passage and immediately outside the exit of the ionizing passage at the block face.

  10. Pemphigus vulgaris and infections: a retrospective study on 155 patients.

    PubMed

    Esmaili, Nafiseh; Mortazavi, Hossein; Noormohammadpour, Pedram; Boreiri, Majid; Soori, Tahereh; Vasheghani Farahani, Iman; Mohit, Mitra

    2013-01-01

    Background. Autoimmune process and immunosuppressive therapy of pemphigus vulgaris would predispose the patients to infections. Aim. We aimed to study the prevalence of infection and pathogenic agents in pemphigus vulgaris patients admitted to dermatology service. Material and methods. This retrospective study was conducted on 155 pemphigus vulgaris patients (68 males, 87 females) admitted to dermatology service between 2009 and 2011. In this study, the diagnosis of pemphigus vulgaris was confirmed by light microscopic and direct immunofluorescence findings. Data were collected through a questionnaire. Results. Of 155 pemphigus vulgaris patients, 33 had infection at admission and 9 acquired nosocomial infection. In addition, 37 cases of oral candidiasis and 15 cases of localized herpes simplex were recorded. Totally, 94 cases of infection were recorded. The occurrence of infection was significantly related to the severity of disease, number of hospital admissions, and presence of diabetes mellitus. The most common pathogenic germs isolated from cultures were Staphylococcus aureus and Escherichia coli. Conclusion. Severity of pemphigus vulgaris and diabetes were directly related with tendency to infections. Staphylococcus aureus and Escherichia coli were the most common pathogenic agents. Due to limitations of retrospective study, a prospective study is recommended.

  11. Pemphigus Vulgaris and Infections: A Retrospective Study on 155 Patients

    PubMed Central

    Esmaili, Nafiseh; Noormohammadpour, Pedram; Boreiri, Majid; Soori, Tahereh; Vasheghani Farahani, Iman; Mohit, Mitra

    2013-01-01

    Background. Autoimmune process and immunosuppressive therapy of pemphigus vulgaris would predispose the patients to infections. Aim. We aimed to study the prevalence of infection and pathogenic agents in pemphigus vulgaris patients admitted to dermatology service. Material and methods. This retrospective study was conducted on 155 pemphigus vulgaris patients (68 males, 87 females) admitted to dermatology service between 2009 and 2011. In this study, the diagnosis of pemphigus vulgaris was confirmed by light microscopic and direct immunofluorescence findings. Data were collected through a questionnaire. Results. Of 155 pemphigus vulgaris patients, 33 had infection at admission and 9 acquired nosocomial infection. In addition, 37 cases of oral candidiasis and 15 cases of localized herpes simplex were recorded. Totally, 94 cases of infection were recorded. The occurrence of infection was significantly related to the severity of disease, number of hospital admissions, and presence of diabetes mellitus. The most common pathogenic germs isolated from cultures were Staphylococcus aureus and Escherichia coli. Conclusion. Severity of pemphigus vulgaris and diabetes were directly related with tendency to infections. Staphylococcus aureus and Escherichia coli were the most common pathogenic agents. Due to limitations of retrospective study, a prospective study is recommended. PMID:23844280

  12. Essential Oil Characterization of Thymus vulgaris from Various Geographical Locations

    PubMed Central

    Satyal, Prabodh; Murray, Brittney L.; McFeeters, Robert L.; Setzer, William N.

    2016-01-01

    Thyme (Thymus vulgaris L.) is a commonly used flavoring agent and medicinal herb. Several chemotypes of thyme, based on essential oil compositions, have been established, including (1) linalool; (2) borneol; (3) geraniol; (4) sabinene hydrate; (5) thymol; (6) carvacrol, as well as a number of multiple-component chemotypes. In this work, two different T. vulgaris essential oils were obtained from France and two were obtained from Serbia. The chemical compositions were determined using gas chromatography–mass spectrometry. In addition, chiral gas chromatography was used to determine the enantiomeric compositions of several monoterpenoid components. The T. vulgaris oil from Nyons, France was of the linalool chemotype (linalool, 76.2%; linalyl acetate, 14.3%); the oil sample from Jablanicki, Serbia was of the geraniol chemotype (geraniol, 59.8%; geranyl acetate, 16.7%); the sample from Pomoravje District, Serbia was of the sabinene hydrate chemotype (cis-sabinene hydrate, 30.8%; trans-sabinene hydrate, 5.0%); and the essential oil from Richerenches, France was of the thymol chemotype (thymol, 47.1%; p-cymene, 20.1%). A cluster analysis based on the compositions of these essential oils as well as 81 additional T. vulgaris essential oils reported in the literature revealed 20 different chemotypes. This work represents the first chiral analysis of T. vulgaris monoterpenoids and a comprehensive description of the different chemotypes of T. vulgaris. PMID:28231164

  13. Plastid transformation in sugar beet: Beta vulgaris.

    PubMed

    De Marchis, Francesca; Bellucci, Michele

    2014-01-01

    Chloroplast biotechnology has assumed great importance in the past 20 years and, thanks to the numerous advantages as compared to conventional transgenic technologies, has been applied in an increasing number of plant species but still very much limited. Hence, it is of utmost importance to extend the range of species in which plastid transformation can be applied. Sugar beet (Beta vulgaris L.) is an important industrial crop of the temperate zone in which chloroplast DNA is not transmitted trough pollen. Transformation of the sugar beet genome is performed in several research laboratories; conversely sugar beet plastome genetic transformation is far away from being considered a routine technique. We describe here a method to obtain transplastomic sugar beet plants trough biolistic transformation. The availability of sugar beet transplastomic plants should avoid the risk of gene flow between these cultivated genetic modified sugar beet plants and the wild-type plants or relative wild species.

  14. Lupus vulgaris in a young girl.

    PubMed

    Goyal, Tarang; Varshney, Anupam; Bakshi, S K

    2013-01-01

    With the estimated global burden of TB being 8.8 million incident cases and 1.1 million deaths from TB in HIV-negative cases and additional 0.35 million deaths in HIV-associated cases,1 the total number of cutaneous TB cases ( < 1-2 % of total cases) becomes significant. With the WHO setting up public-private mix partnerships and a millenium development goal of a 50% reduction in the total number of incident cases, the case detection and reporting of unusual cutaneous TB cases becomes very important. We present a case of lupus vulgaris in a young girl with rapid progression of a large plaque with hypertrophic features in the periphery. The case is unusual due to its rapid progression, unusual site and extensive giant form which have never been reported previously.

  15. Pemphigus vulgaris: gingival involvement. A case report.

    PubMed

    Weinberg, M A; Abitbol, T E

    1995-01-01

    Pemphigus is an autoimmune disease in which intraepithelial vesicles and bullae of the skin and oral mucosa are produced by the action of autoantibodies against specific desmosomal proteins of squamous epithelium. Usually, oral lesions will appear before skin lesions, and in a majority of the cases only oral lesions are present. The dentist may then be the first to make and early diagnosis. The importance of this case report is to alert the dentist that subtle gingival lesions can be recognized and treated early in such a life-threatening disease. Diagnosis is based on the clinical presentation and confirmed by histologic study and direct immunofluorescence. This case describes the clinical signs, symptoms, histology, and immunofluorescence of pemphigus vulgaris of the gingiva.

  16. Pregnancy-Associated "Cutaneous Type" Pemphigus Vulgaris.

    PubMed

    Rangel, Javier

    2016-01-01

    The development of pemphigus, including pemphigus vulgaris (PV) and pemphigus foliaceus, during pregnancy is rare. PV manifests with mucosal and/or cutaneous erosions with flaccid bullae that are histologically characterized by suprabasilar acantholysis. In contrast, pemphigus foliaceus manifests with cutaneous-only involvement and superficial epidermal acantholysis. Enzyme-linked immunosorbent assay specific for autoantibodies against desmoglein 1 and desmoglein 3 aids in the diagnosis and differentiation between pemphigus subtypes. High-dose systemic corticosteroids are first-line agents in management of PV, yet their potential long-term use raises complex management issues associated with pregnancy and fetal risk. Here we report a rare case of cutaneous-limited PV in association with pregnancy.

  17. Pemphigus vulgaris-associated interstitial lung disease.

    PubMed

    Bai, Yi-Xiu; Chu, Jin-Gang; Xiao, Ting; Chen, Hong-Duo

    2016-07-01

    Autoimmune bullous diseases (AIBDs)-associated interstitial lung disease (ILD) is extremely rare. Pemphigus vulgaris (PV) is an intraepidermal autoimmune blistering disease caused by circulating autoantibodies against desmoglein. To date, PV-associated ILD has rarely been reported in English literature. We report a rare association of PV and ILD. A 53-year-old Chinese female with PV for 8 months developed ILD after a relapse of PV for 2 months due to discontinuation of oral prednisone by herself. She was successfully treated by systemic methylprednisolone. Taken previously reported bullous pemphigoid-associated ILD and linear IgA/IgG bullous dermatosis-associated ILD together, in general, AIBDs-associated ILD occurs when AIBDs relapse or are not controlled, responds well to systemic corticosteroids, and has a relatively better prognosis when compared with rheumatoid arthritis- or dermatomyositis-associated ILD.

  18. Acne vulgaris and rosacea: evaluation and management.

    PubMed

    Webster, G F

    2001-01-01

    Acne vulgaris, commonly termed acne, is an extremely common disease. It can be found in nearly all teenagers to some degree as well as in women in their 30s. Regardless of severity, acne often has a greater psychologic effect than cutaneous effect. Indeed, most patients overestimate the severity of their disease, while most physicians underestimate its impact on their patients. Studies have shown that people with severe acne as teens are less employable as adults and that self-esteem is low. When combined with other adolescent tensions, acne can be a difficult disease to treat. Rosacea, which usually starts in the late 20s, may affect the eyes as well as the skin. This article describes the pathogenesis of acne and rosacea and treatment approaches the primary care physician can use.

  19. [The pathogenesis of acne vulgaris (author's transl)].

    PubMed

    Gloor, M; Habedank, W D

    1976-05-14

    Stickl's method of oral treatment of acne vulgaris with antigens has been carried out on 26 test persons. During the treatment the number of comedones increased significantly and the number of papules decreased significantly. Biochemically, a significant increase of the free fatty acids and a significant decrease of the triglycerides could be demonstrated in the skin surface lipids, the total amount remaining unchanged. The following important conclusions for the pathogenesis of acne may be drawn: 1. The living conditions for Corynebacterium acnes on the surface of the skin or in the ducts of sebaceous glands respectively are influenced by the immunological system of the host. 2. The free fatty acids have a comedogenic effect in vivo. 3. The free fatty acids are not responsible for the development of inflammatory acne efflorescences.

  20. Setting the target for pemphigus vulgaris therapy

    PubMed Central

    Ellebrecht, Christoph T.

    2017-01-01

    Despite the rising incidence of autoimmunity, therapeutic options for patients with autoimmune disease still rely on decades-old immunosuppressive strategies that risk severe and potentially fatal complications. Thus, novel therapeutic approaches for autoimmune diseases are greatly needed in order to minimize treatment-related toxicity. Such strategies would ideally target only the autoreactive immune components to preserve beneficial immunity. Here, we review how several decades of basic, translational, and clinical research on the immunology of pemphigus vulgaris (PV), an autoantibody-mediated skin disease, have enabled the development of targeted immunotherapeutic strategies. We discuss research to elucidate the pathophysiology of PV and how the knowledge afforded by these studies has led to the preclinical and clinical testing of targeted approaches to neutralize autoantibodies, to induce antigen-specific tolerance, and to specifically eliminate autoreactive B cells in PV. PMID:28289723

  1. Does Octopus vulgaris have preferred arms?

    PubMed

    Byrne, Ruth A; Kuba, Michael J; Meisel, Daniela V; Griebel, Ulrike; Mather, Jennifer A

    2006-08-01

    Previous behavioral studies in Octopus vulgaris revealed lateralization of eye use. In this study, the authors expanded the scope to investigate arm preferences. The octopus's generalist hunting lifestyle and the structure of their arms suggest that these animals have no need to designate specific arms for specific tasks. However, octopuses also show behaviors, like exploration, in which only single or small groups of arms are involved. Here the authors show that octopuses had a strong preference for anterior arm use to reach for and explore objects, which points toward a task division between anterior and posterior arms. Four out of 8 subjects also showed a lateral bias. In addition, octopuses had a preference for a specific arm to reach into a T maze to retrieve a food reward. These findings give evidence for limb-specialization in an animal whose 8 arms were believed to be equipotential.

  2. A mechanism that triggers double arcing during plasma arc cutting

    NASA Astrophysics Data System (ADS)

    Nemchinsky, Valerian

    2009-10-01

    Double arcing (DA) is a phenomenon when a transferred arc, flowing inside an electrically insulated nozzle, breaks into two separate arcs: one that connects the cathode and the nozzle and another that connects the nozzle and a work-piece. It is a commonly accepted opinion that the reason for DA is high voltage drop in the plasma inside the nozzle. However, the specific mechanism that triggers the DA development is not clear. In this paper, we propose such a mechanism. Dielectric films deposited inside the nozzle's orifice play the key role in this mechanism. These films are charged by ion current from plasma. A strong electric field is created inside the film and at the boundary of the film and clean metal of the nozzle. This gives rise to a thermo-field electron emission from the clean metal that borders the film. Emitted electrons are accelerated at the voltage drop between the nozzle and plasma. These electrons produce extra ions, which in turn move back to the film and additionally charge it. This sequence of events leads to explosive instability if the voltage drop inside the nozzle is high enough. Experiments to check the proposed mechanism are suggested.

  3. Chlorella Protein Hydrolysate Attenuates Glucose Metabolic Disorder and Fatty Liver in High-fat Diet-induced Obese Mice.

    PubMed

    Noguchi, Naoto; Yanagita, Teruyoshi; Rahman, Shaikh Mizanoor; Ando, Yotaro

    2016-07-01

    Chlorella (Parachlorella beijerinckii) powder is reported to show a preventive effect against metabolic syndromes such as arteriosclerosis, hyperlipidemia, and hypertension. Approximately 60% of the chlorella content is protein. In order to understand the role of chlorella protein, we prepared a chlorella protein hydrolysate (CPH) by protease treatment. Male C57BL/6 mice were divided into three groups: a normal diet group, high-fat diet (HFD) group, and high-fat diet supplemented with CPH (HFD+CPH) group. The CPH administration improved glucose intolerance, insulin sensitivity, and adipose tissue hypertrophy in the high-fat diet-fed mice. In addition, the HFD+CPH group had significantly decreased liver total cholesterol and triglyceride levels compared with those in the HFD group. Furthermore, the HFD+CPH group had a decreased level of monocyte chemotactic protein-1 (MCP-1) in serum and a lower MCP-1 mRNA expression level in adipose tissue compared with the HFD group. The present study suggests that chlorella protein hydrolysate can prevent a high-fat diet-induced glucose disorder and fatty liver by inhibiting adipocyte hypertrophy and reducing the MCP-1 protein and gene expression.

  4. Filters for cathodic arc plasmas

    DOEpatents

    Anders, Andre; MacGill, Robert A.; Bilek, Marcela M. M.; Brown, Ian G.

    2002-01-01

    Cathodic arc plasmas are contaminated with macroparticles. A variety of magnetic plasma filters has been used with various success in removing the macroparticles from the plasma. An open-architecture, bent solenoid filter, with additional field coils at the filter entrance and exit, improves macroparticle filtering. In particular, a double-bent filter that is twisted out of plane forms a very compact and efficient filter. The coil turns further have a flat cross-section to promote macroparticle reflection out of the filter volume. An output conditioning system formed of an expander coil, a straightener coil, and a homogenizer, may be used with the magnetic filter for expanding the filtered plasma beam to cover a larger area of the target. A cathodic arc plasma deposition system using this filter can be used for the deposition of ultrathin amorphous hard carbon (a-C) films for the magnetic storage industry.

  5. The SOAR Gravitational Arc Survey

    NASA Astrophysics Data System (ADS)

    Makler, M.; Furlanetto, C.; Santiago, B. X.; Caminha, G. B.; Cypriano, E.; Cibirka, N.; Pereira, M. E. S.; Bom, C. R. D.; Lima, M. P.; Brandt, C. H.; Neto, A. F.; Estrada, J.; Lin, H.; Hao, J.; McKay, T. M.; da Costa, L. N.; Maia, M. A. G.

    2014-10-01

    We present the first results of the SOAR Gravitational Arc Survey (SOGRAS). The survey imaged 47 clusters in two redshift intervals centered at z=0.27 and z=0.55, targeting the richest clusters in each interval. Images were obtained in the g', r' and i' bands with a median seeing of 0.83, 0.76 and 0.71 arcsec, respectively, in these filters. Most of the survey clusters are located within the Sloan Digital Sky Survey (SDSS) Stripe-82 region and all of them are in the SDSS footprint. We present the first results of the survey, including the 6 best strong lensing systems, photometric and morphometric catalogs of the galaxy sample, and cross matches of the clusters and galaxies with complementary samples (spectroscopic redshifts, photometry in several bands, X-ray and Sunyaev Zel'dovich clusters, etc.), exploiting the synergy with other surveys in Stripe-82. We apply several methods to characterize the gravitational arc candidates, including the Mediatrix method (Bom et al. 2012) and ArcFitting (Furlanetto et al. 2012), and for the subtraction of galaxy cluster light. Finally, we apply strong lensing inversion techniques to the best systems, providing constraints on their mass distribution. The analyses of a spectral follow-up with Gemini and the derived dynamical masses are presented in a poster submitted to this same meeting (Cibirka et al.). Deeper follow-up images with Gemini strengthen the case for the strong lensing nature of the candidates found in this survey.

  6. Treatment of African catfish, Clarias gariepinus wastewater utilizing phytoremediation of microalgae, Chlorella sp. with Aspergillus niger bio-harvesting.

    PubMed

    Nasir, Nurfarahana Mohd; Bakar, Nur Syuhada Abu; Lananan, Fathurrahman; Abdul Hamid, Siti Hajar; Lam, Su Shiung; Jusoh, Ahmad

    2015-08-01

    This study focuses on the evaluation of the performance of Chlorella sp. in removing nutrient in aquaculture wastewater and its correlation with the kinetic growth of Chlorella sp. The treatment was applied with various Chlorella sp. inoculation dosage ranging from 0% to 60% (v/v) of wastewater. The optimum inoculation dosage was recorded at 30% (v/v) with effluent concentration of ammonia and orthophosphate recording at 0.012mgL(-1) and 0.647mgL(-1), respectively on Day 11. The optimum dosage for bio-flocculation process was obtained at 30mgL(-1) of Aspergillus niger with a harvesting efficiency of 97%. This type of development of phytoremediation with continuous bio-harvesting could promote the use of sustainable green technology for effective wastewater treatment.

  7. Cultivation of Monoraphidium sp., Chlorella sp. and Scenedesmus sp. algae in Batch culture using Nile tilapia effluent.

    PubMed

    Guerrero-Cabrera, Luis; Rueda, José A; García-Lozano, Hiram; Navarro, A Karin

    2014-06-01

    Monoraphidium sp., Chlorella sp. and Scenedesmus sp. algae were cultured in three volumes of Tilapia Effluent Medium (TEM) in comparison with the Bold Basal Medium (BBM) (Nichols and Bold, 1965). Specific growth rate (μ'), biomass dry productivity (Q), volumetric productivity (Qv) as well as lipid and protein content were measured. Then, volumetric productivities for both lipids and proteins were calculated (QVL and QVP). In Scenedesmus sp., BBM produced higher μ' and Qv than TEM in 1.5L volume. Chlorella sp. showed a higher QVL for BBM than TEM. Any observed difference in protein or lipid productivities among volumes was in favor of a greater productivity for 1.5L volume. Even when TEM had a larger protein content in Chlorella sp. than BBM, QVP was not different. Current results imply that TEM can be used as an alternative growth medium for algae when using Batch cultures, yet productivity is reduced.

  8. [Development of Zabrotes subfasciatus (Boh.) (Coleoptera: Chrysomelidae, Bruchinae) in genotypes of Phaseolus vulgaris L. (Fabaceae) cultivated in the State of Parana and containing arcelin].

    PubMed

    Ribeiro-Costa, Cibele S; Pereira, Paulo Roberto V da S; Zukovski, Luciana

    2007-01-01

    This research intended to evaluate the development of Zabrotes subfasciatus (Boh.), a stored-grain pest, on bean genotypes (Phaseolus vulgaris L.) commonly cultivated in the State of Parana and containing arcelin, and the possible resistance of these genotypes to the bruchine. Tests were performed under laboratory conditions (27 masculineC, fotophase 12h, 50 +/- 10 % RH) with the genotypes TPS-Bionobre, IAC-Una, IPR-Uirapuru, IAPAR 44, IPR Juriti, IAPAR 81, Pérola, Carioca, Bolinha, and two others containing arcelin, Arc 1 and Arc 2. The genotypes with Arc 1 and 2 alleles caused higher mortality of immature stages; in Arc 1 developmental period was prolonged and the male and female dry weights were the lowest, suggesting an antibiosis mechanism of resistance. Non-preference for oviposition was not observed for these two genotypes. Among varieties without arcelin, IAPAR 44 was the most resistant to the bruchid, being the least preferred for oviposition, and promoting low percentage of viable eggs, long developmental period and reduced male and female adult dry weight. Perola, IPR Juriti and Bolinha with high number of eggs and viable eggs, low mortality of immature stages, were the most susceptible.

  9. Salt Stress in Desulfovibrio vulgaris Hildenborough: An integratedgenomics approach

    SciTech Connect

    Mukhopadhyay, Aindrila; He, Zhili; Alm, Eric J.; Arkin, Adam P.; Baidoo, Edward E.; Borglin, Sharon C.; Chen, Wenqiong; Hazen, Terry C.; He, Qiang; Holman, Hoi-Ying; Huang, Katherine; Huang, Rick; Hoyner,Dominique C.; Katz, Natalie; Keller, Martin; Oeller, Paul; Redding,Alyssa; Sun, Jun; Wall, Judy; Wei, Jing; Yang, Zamin; Yen, Huei-Che; Zhou, Jizhong; Keasling Jay D.

    2005-12-08

    The ability of Desulfovibrio vulgaris Hildenborough to reduce, and therefore contain, toxic and radioactive metal waste has made all factors that affect the physiology of this organism of great interest. Increased salinity is an important and frequent fluctuation faced by D. vulgaris in its natural habitat. In liquid culture, exposure to excess salt resulted in striking elongation of D. vulgaris cells. Using data from transcriptomics, proteomics, metabolite assays, phospholipid fatty acid profiling, and electron microscopy, we used a systems approach to explore the effects of excess NaCl on D. vulgaris. In this study we demonstrated that import of osmoprotectants, such as glycine betaine and ectoine, is the primary mechanism used by D. vulgaris to counter hyperionic stress. Several efflux systems were also highly up-regulated, as was the ATP synthesis pathway. Increases in the levels of both RNA and DNA helicases suggested that salt stress affected the stability of nucleic acid base pairing. An overall increase in the level of branched fatty acids indicated that there were changes in cell wall fluidity. The immediate response to salt stress included up-regulation of chemotaxis genes, although flagellar biosynthesis was down-regulated. Other down-regulated systems included lactate uptake permeases and ABC transport systems. The results of an extensive NaCl stress analysis were compared with microarray data from a KCl stress analysis, and unlike many other bacteria, D. vulgaris responded similarly to the two stresses. Integration of data from multiple methods allowed us to develop a conceptual model for the salt stress response in D. vulgaris that can be compared to those in other microorganisms.

  10. Salt stress in Desulfovibrio vulgaris Hildenborough: an integrated genomics approach.

    PubMed

    Mukhopadhyay, Aindrila; He, Zhili; Alm, Eric J; Arkin, Adam P; Baidoo, Edward E; Borglin, Sharon C; Chen, Wenqiong; Hazen, Terry C; He, Qiang; Holman, Hoi-Ying; Huang, Katherine; Huang, Rick; Joyner, Dominique C; Katz, Natalie; Keller, Martin; Oeller, Paul; Redding, Alyssa; Sun, Jun; Wall, Judy; Wei, Jing; Yang, Zamin; Yen, Huei-Che; Zhou, Jizhong; Keasling, Jay D

    2006-06-01

    The ability of Desulfovibrio vulgaris Hildenborough to reduce, and therefore contain, toxic and radioactive metal waste has made all factors that affect the physiology of this organism of great interest. Increased salinity is an important and frequent fluctuation faced by D. vulgaris in its natural habitat. In liquid culture, exposure to excess salt resulted in striking elongation of D. vulgaris cells. Using data from transcriptomics, proteomics, metabolite assays, phospholipid fatty acid profiling, and electron microscopy, we used a systems approach to explore the effects of excess NaCl on D. vulgaris. In this study we demonstrated that import of osmoprotectants, such as glycine betaine and ectoine, is the primary mechanism used by D. vulgaris to counter hyperionic stress. Several efflux systems were also highly up-regulated, as was the ATP synthesis pathway. Increases in the levels of both RNA and DNA helicases suggested that salt stress affected the stability of nucleic acid base pairing. An overall increase in the level of branched fatty acids indicated that there were changes in cell wall fluidity. The immediate response to salt stress included up-regulation of chemotaxis genes, although flagellar biosynthesis was down-regulated. Other down-regulated systems included lactate uptake permeases and ABC transport systems. The results of an extensive NaCl stress analysis were compared with microarray data from a KCl stress analysis, and unlike many other bacteria, D. vulgaris responded similarly to the two stresses. Integration of data from multiple methods allowed us to develop a conceptual model for the salt stress response in D. vulgaris that can be compared to those in other microorganisms.

  11. The epidemiology of acne vulgaris in late adolescence

    PubMed Central

    Lynn, Darren D; Umari, Tamara; Dunnick, Cory A; Dellavalle, Robert P

    2016-01-01

    Importance Acne vulgaris is the most common skin condition affecting late adolescents across the globe. Although prior studies have evaluated epidemiologic patterns of acne vulgaris in various ethnicities and regions, adequate understanding of the worldwide burden of the disease associated with patients in their late adolescence (15–19-year olds) remains lacking. Objective To assess the global burden of the disease associated with acne vulgaris for late adolescents (15–19-year olds) and provide an overview of the epidemiology, pathophysiology, and treatment options for acne in this population. Design Database summary study. Setting Global Burden of Disease Study 2010 database. Participants Global Burden of Disease regions comprised countries with prevalence of acne vulgaris between the ages of 15 and 19 years. Main outcomes and measures Geographic region-level disability-adjusted life year rates (per 100,000 persons) associated with acne vulgaris in years 1990 through 2010. Median percentage change in disability-adjusted life year rates was estimated for each region across the specified study period. Conclusion and relevance Acne vulgaris-associated disease burden exhibits global distribution and has continued to grow in prevalence over time within this population. This continued growth suggests an unmet dermatologic need worldwide for this disorder and potential opportunities for improved access and delivery of dermatologic care. Our analysis of the literature reveals numerous opportunities for enhanced patient care. To that end, we highlight some of the effective and promising treatments currently available and address important factors, such as sex, nationality, genetics, pathophysiology, and diet, as they relate to acne vulgaris in late adolescence. PMID:26955297

  12. Impact of daily Chlorella consumption on serum lipid and carotenoid profiles in mildly hypercholesterolemic adults: a double-blinded, randomized, placebo-controlled study

    PubMed Central

    2014-01-01

    Background High level of serum cholesterol is considered to be a major risk factor for cardiovascular disease (CVD). A double-blinded, randomized, placebo-controlled trial was performed to test the hypothesis that a daily intake of Chlorella may improve serum lipid profile through enhancement of serum carotenoid concentration in mildly hypercholesterolemic subjects. Methods Eligible subjects (n = 63) were randomized to either Chlorella (5 g/day) or placebo for a double-blinded trial with a 2-week lead-in period and a 4-week intervention period. Serum triglycerides, total cholesterol, lipoproteins, apolipoproteins and carotenoids were assessed at the beginning and the end of the trial. Results Compared with the control group, the Chlorella group exhibited remarkable changes in total cholesterol (Chlorella −1.6%; placebo 0.03%; P = 0.036), triglycerides (Chlorella −10.3%; placebo 11.9%; P = 0.002), lutein/zeaxanthin (Chlorella 89.6%; placebo −1.7%; P < 0.0001), and α-carotene (Chlorella 163.6%; placebo 15%; P < 0.0001). Improvement of serum lipids was supported by significant reductions of very low-density lipoprotein cholesterol (Chlorella −11%; placebo 11.8%; P = 0.006), apolipoprotein B (Chlorella −1.5%; placebo 1.7%; P = 0.044), non high-density lipoprotein (Chlorella −2.6%; placebo −0.5%; P = 0.032), and high-density lipoprotein/triglycerides (Chlorella 4.0%; placebo −9.5%; P = 0.023), suggesting an inhibitory effect of Chlorella on the intestinal absorption of dietary and endogenous lipids. Further, the changes of serum lipids appeared to be associated with the changes of serum carotenoids. Conclusion Daily consumption of Chlorella supplements provided the potential of health benefits reducing serum lipid risk factors, mainly triglycerides and total cholesterol, in mildly hypercholesterolemic subjects. The effect was related to carotenoid consumption. Trial registration WHO International Clinical Trials

  13. Hydrolysis of Chlorella biomass for fermentable sugars in the presence of HCl and MgCl2.

    PubMed

    Zhou, Na; Zhang, Yimin; Wu, Xiaobin; Gong, Xiaowu; Wang, Qinhong

    2011-11-01

    When Chlorella biomass was hydrolyzed in the presence of 2% HCl and 2.5% MgCl(2), a sugar concentration of nearly 12%, and a sugar recovery of about 83% was obtained. Fermentation experiments demonstrated that glucose in the Chlorella biomass hydrolysates was converted into ethanol by Saccharomyces cerevisiae with a yield of 0.47 g g(-1), which is 91% of the theoretical yield. This chemical hydrolysis approach is thus a novel route for the hydrolysis of biomass to generate fermentable sugars.

  14. Effects of dietary recombinant chlorella supplementation on growth performance, meat quality, blood characteristics, excreta microflora, and nutrient digestibility in broilers.

    PubMed

    Choi, H; Jung, S K; Kim, J S; Kim, K-W; Oh, K B; Lee, P-Y; Byun, S J

    2017-03-01

    The use of chlorella as an immune stimulant to enhance nonspecific host defense mechanisms or as an antimicrobial to inhibit bacterial growth has been reported. Thus, the aim of the present study was to clarify the effect of recombinant chlorella supplementation on growth performance, meat quality, and the blood profile, excreta microflora, and nutrient digestibility in broilers. A total of 375 one-day-old ROSS 308 broilers (male and female) were allotted to 5 dietary treatments using 5 cages with 15 chicks per cage. Treatments were: 1) NC, basal diet supplemented with 1.0% E. coli fermented liquor (EFL); 2) PC1, 0.2% EFL with chlorella; 3) PC2, 1.0% EFL with chlorella; 4) T1, 0.2% EFL with chlorella (anti-viral); and 5) T2, 1.0% EFL with chlorella (anti-viral). The broilers in the T2 treatment groups showed higher body weight gain (BGW) by 2.55% (P < 0.01) and lower feed conversion ratio (FCR) by 2.75% (P < 0.05) compared with those fed the control NC treatment group. Moreover, the blood contents of blood urea nitrogen (BUN), creatinine, and IgA in the broilers of the T2 treatment group were significantly increased by 28.12, 23.07, and 29.72%, respectively -more than those found in the broilers of the NC treatment group (P < 0.01). In contrast, the LDL/C in the blood from the animals in the T2 treatment group was significantly decreased by 23.23% - more than that in the blood from the NC broilers (P < 0.05). Based on these results, we suggest that the dietary supplementation of broilers with recombinant chlorella could improve their growth performance, increase the concentration of IgA and apparently metabolizable nitrogen in the blood, and decrease ammonia emissions. Therefore, our findings have important implications for the effect of recombinant chlorella supplementation through increasing the concentration of IgA and the level of metabolizable nitrogen.

  15. QUES, a new Phaseolus vulgaris genotype resistant to common bean weevils, contains the Arcelin-8 allele coding for new lectin-related variants.

    PubMed

    Zaugg, Isabelle; Magni, Chiara; Panzeri, Dario; Daminati, Maria Gloria; Bollini, Roberto; Benrey, Betty; Bacher, Sven; Sparvoli, Francesca

    2013-03-01

    In common bean (Phaseolus vulgaris L.), the most abundant seed proteins are the storage protein phaseolin and the family of closely related APA proteins (arcelin, phytohemagglutinin and α-amylase inhibitor). High variation in APA protein composition has been described and the presence of arcelin (Arc) has been associated with bean resistance against two bruchid beetles, the bean weevil (Acanthoscelides obtectus Say) and the Mexican bean weevil (Zabrotes subfasciatus Bohemian). So far, seven Arc variants have been identified, all in wild accessions, however, only those containing Arc-4 were reported to be resistant to both species. Although many efforts have been made, a successful breeding of this genetic trait into cultivated genotypes has not yet been achieved. Here, we describe a newly collected wild accession (named QUES) and demonstrate its resistance to both A. obtectus and Z. subfasciatus. Immunological and proteomic analyses of QUES seed protein composition indicated the presence of new Arc and arcelin-like (ARL) polypeptides of about 30 and 27 kDa, respectively. Sequencing of cDNAs coding for QUES APA proteins confirmed that this accession contains new APA variants, here referred to as Arc-8 and ARL-8. Moreover, bioinformatic analysis showed the two proteins are closely related to APA components present in the G12949 wild bean accession, which contains the Arc-4 variant. The presence of these new APA components, combined with the observations that they are poorly digested and remain very abundant in A. obtectus feces, so-called frass, suggest that the QUES APA locus is involved in the bruchid resistance. Moreover, molecular analysis indicated a lower complexity of the locus compared to that of G12949, suggesting that QUES should be considered a valuable source of resistance for further breeding purposes.

  16. Delayed diagnosis in a case of lupus vulgaris with unusual localization.

    PubMed

    Ceylan, Can; Gerceker, Bengu; Ozdemir, Fezal; Kazandi, Alican

    2004-01-01

    Lupus vulgaris is the most common form of cutaneous tuberculosis, and the usual sites of involvement are the head and neck. We present a forty-six-year-old woman with lupus vulgaris on the external surface of the left leg and foot, an unusual site. Based on histopathological and clinical features, this case was diagnosed as lupus vulgaris with unusual localization.

  17. Evaluation of higher plant virus resistance genes in the green alga, Chlorella variabilis NC64A, during the early phase of infection with Paramecium bursaria chlorella virus-1

    PubMed Central

    Rowe, Janet M.; Dunigan, David D.; Blanc, Guillaume; Gurnon, James R.; Xia, Yuannan; Van Etten, James L.

    2014-01-01

    With growing industrial interest in algae plus their critical roles in aquatic systems, the need to understand the effects of algal pathogens is increasing. We examined a model algal host–virus system, Chlorella variabilis NC64A and virus, PBCV-1. C. variabilis encodes 375 homologs to genes involved in RNA silencing and in response to virus infection in higher plants. Illumina RNA-Seq data showed that 325 of these homologs were expressed in healthy and early PBCV-1 infected (≤60 min) cells. For each of the RNA silencing genes to which homologs were found, mRNA transcripts were detected in healthy and infected cells. C. variabilis, like higher plants, may employ certain RNA silencing pathways to defend itself against virus infection. To our knowledge this is the first examination of RNA silencing genes in algae beyond core proteins, and the first analysis of their transcription during virus infection. PMID:23701839

  18. Optimal N:P ratios of growth media: quantification of nutrient-replete growth rates in five ion hyperspace for Chlorella vulgaris (Dinophyceae) and Peridinium cinctum (Dinophyceae).

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this study our principal goal was to quantify the main effects and interactions of several primary nutrient and bulk solution ions. The total ion concentration range chosen spans fresh to brackish waters (1-30 milliMolar) and explores most of the hypervolume delineated by the five ion/concentrat...

  19. Review of switching arcs and plasma chemistry

    NASA Astrophysics Data System (ADS)

    Benenson, D. M.; Gilmour, A. S., Jr.; Dollinger, R. E.; Nagamatsu, H. T.; Pfender, E.; Warder, R. C., Jr.

    1980-05-01

    Physical processes in switching arcs are considered in such applications as circuit interruption (in high pressure, high voltage gas blast circuit breakers and vacuum arc interrupters), fault current limiting (principally through vacuum arc devices), and pulse power systems (using vacuum arcs). The physics of arc heaters, associated with processes in the anode region, are described. Analytical models of (1) the current zero region and interrupter performance of gas blast interrupters and (2) the heat transfer mechanisms in the anode region of arc heaters, are discussed. Selected diagnostic techniques are presented. Applications of plasma chemistry involving the high pressure, equilibrium (thermal) plasma are noted. Low pressure (nonequilibrium) plasma processing is described through mechanisms associated with coating, deposition, and etching applications.

  20. ARC length control for plasma welding

    NASA Technical Reports Server (NTRS)

    Iceland, William F. (Inventor)

    1988-01-01

    A control system to be used with a plasma arc welding apparatus is disclosed. The plasma arc welding apparatus includes a plasma arc power supply, a contactor, and an electrode assembly for moving the electrode relative to a work piece. The electrode assembly is raised or lowered by a drive motor. The present apparatus includes a plasma arc adapter connected across the power supply to measure the voltage across the plasma arc. The plasma arc adapter forms a dc output signal input to a differential amplifier. A second input is defined by an adjustable resistor connected to a dc voltage supply to permit operator control. The differential amplifier forms an output difference signal provided to an adder circuit. The adder circuit then connects with a power amplifier which forms the driving signal for the motor. In addition, the motor connects to a tachometor which forms a feedback signal delivered to the adder to provide damping, therby avoiding servo loop overshoot.