Stabilization of waste-activated sludge through the anoxic-aerobic digestion process

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hashimoto, S.; Fujita, M.; Terai, K.

1982-08-01

During the aerobic digestion process, the nitrogen which had been embedded in the activated sludge is solubilized to form ammoniacal and nitric nitrogen which are in turn transferred to the liquor and cause the increase of nitrogen loading in the sewage treatment plant. In this study, the anoxic-aerobic sludge digestion system which is a modified form of the conventional aerobic sludge digestion is made up of aerobic and anoxic tanks and are designed to remove both the volatile suspended solids and the total nitrogen (TN) simultaneously. The removal efficiencies of both VSS and TN were investigated by feeding waste-activated sludgemore » continuously and semicontinuously. The maximum percent reduction of both VSS and TN was achieved at a Q /SUB r/ /Q /SUB s/ ratio of 2 in the continuous process. The semicontinuous process was used to improve the nitrogen removal efficiency further. In the semicontinuous process, the VSS reduction efficiency as well as the nitrogen removal efficiency increased remarkably under a constant Q /SUB r/ /Q /SUB s/ ratio of 2. This process also achieved a VSS reduction efficiency higher than the aerobic digestion process (control). It was suggested that the additional anoxic tank enhanced the sludge digestion. Furthermore, the anoxic-aerobic digestion system can be applied to other treatment media like the primary sludge, industrial sludge, animal manure, etc.« less

Stabilization of waste-activated sludge through the anoxic-aerobic digestion process.

PubMed

Hashimoto, S; Fujita, M; Terai, K

1982-08-01

During the aerobic digestion process, the nitrogen which had been embedded in the activated sludge is solubilized to form ammoniacal and nitric nitrogen which are in turn transferred to the liquor and cause the increase of nitrogen loading in the sewage treatment plant. In this study, the anoxic-aerobic sludge digestion system which is a modified form of the conventional aerobic sludge digestion is made up of aerobic and anoxic tanks and are designed to remove both the volatile suspended solids and the total nitrogen (TN) simultaneously. The removal efficiencies of both VSS and TN were investigated by feeding waste-activated sludge continuously and semicontinuously. The maximum percent reduction of both VSS and TN was achieved at a Q(r)/Q(s) ratio of 2 in the continuous process. The semicontinuous process was used to improve the nitrogen removal efficiency further. In the semicontinuous process, the VSS reduction efficiency as well as the nitrogen removal efficiency increased remarkably under a constant Q(r)/Q(s) ratio of 2. This process also achieved a VSS reduction efficiency higher than the aerobic digestion process (control). It was suggested that the additional anoxic tank enhanced the sludge digestion. Furthermore, the anoxic-aerobic digestion system can be applied to other treatment media like the primary sludge, industrial sludge, animal manure, etc.

Treating an aged pentachlorophenol- (PCP-) contaminated soil through three sludge handling processes, anaerobic sludge digestion, post-sludge digestion and sludge land application.

PubMed

Chen, S T; Berthouex, P M

2001-01-01

The extensive pentachlorophenol (PCP) contamination and its increasing treatment costs motivate the search for a more competitive treatment alternative. In a municipal wastewater treatment plant, anaerobic sludge-handling processes comprises three bio-processes, namely the anaerobic sludge digestion, post-sludge digestion and sludge land application, which reduce sludge organic content and make sludge a good fertilizer for land application. Availability and effectiveness make the anaerobic sludge handling processes potential technologies to treat PCP-contaminated soil. The technical feasibility of using anaerobic sludge bioprocesses was studied by treating PCP soil in two pilot digesters to simulate the primary sludge digestion, in serum bottles to mimic the post-sludge digestion, and in glass pans to represent the on-site sludge application. For primary digestion, the results showed that up to 0.98 and 0.6 mM of chemical and soil PCP, respectively, were treated at nearly 100% and 97.5% efficiencies. The PCP was transformed 95% to 3-MCP, 4.5% to 3,4-DCP, and 0.5% to 3,5-DCP. For post-digestion, 100% pure chemical PCP and greater than 95% soil PCP were removed in less than 6 months with no chlorophenol residues of any kind. Complete removal of PCP by-products makes this process a good soil cleanup method. For on-site treatment, PCP was efficiently treated by multiple sludge application; however, the PCP residue was observed due to the high initial PCP content in soil. Overall, more mass PCP per unit sludge per day was processed using the primary sludge digestion than the on-site soil treatment or post-sludge digestion. And, sludge acclimation resulted in better PCP treatment efficiencies with all three processes.

In vivo digestion of bovine milk fat globules: effect of processing and interfacial structural changes. II. Upper digestive tract digestion.

PubMed

Gallier, Sophie; Zhu, Xiang Q; Rutherfurd, Shane M; Ye, Aiqian; Moughan, Paul J; Singh, Harjinder

2013-12-01

The aim of this research was to study the effect of milk processing on the in vivo upper digestive tract digestion of milk fat globules. Fasted rats were serially gavaged over a 5h period with cream from raw, pasteurised, or pasteurised and homogenised milk. Only a few intact dietary proteins and peptides were present in the small intestinal digesta. Significantly (P<0.05) more longer chain (C≥10) fatty acids were present in the digesta of rats gavaged with raw (448 mg g(-1) digesta dry matter (DDM)) and homogenised creams (528 mg g(-1) DDM), as compared to pasteurised and homogenised cream (249 mg g(-1) DDM). Microscopy techniques were used to investigate the structural changes during digestion. Liquid-crystalline lamellar phases surrounding the fat globules, fatty acid soap crystals and lipid-mucin interactions were evident in all small intestinal digesta. Overall, the pasteurised and homogenised cream appeared to be digested to a greater extent. Copyright © 2013 Elsevier Ltd. All rights reserved.

Sulfur Removal by Adding Iron During the Digestion Process of High-sulfur Bauxite

NASA Astrophysics Data System (ADS)

Zhanwei, Liu; Hengwei, Yan; Wenhui, Ma; Keqiang, Xie; Dunyong, Li; Licong, Zheng; Pengfei, Li

2018-04-01

This paper proposes a novel approach to sulfur removal by adding iron during the digestion process. Iron can react with high-valence sulfur (S2O3 2-, SO3 2-, SO4 2-) to generate S2- at digestion temperature, and then S2- enter red mud in the form of Na3FeS3 to be removed. As iron dosage increases, high-valence sulfur concentration decreases, but the concentration of S2- increases; sulfur digestion rate decreases while sulfur content in red mud markedly increases; the alumina digestion rate, conversely, remains fairly stable. So sulfur can be removed completely by adding iron in digestion process, which provide a theoretical basis for the effective removal of sulfur in alumina production process.

Interactions between seed traits and digestive processes determine the germinability of bird-dispersed seeds

PubMed Central

Soons, Merel B.

2018-01-01

Waterbirds disperse a wide range of plant seeds via their guts, promoting biotic connectivity between isolated habitat patches. However, the intensity of digestive forces encountered by seeds, and therefore their potential to survive digestive tract passage, varies within and between waterbird species. Here, we investigate under controlled conditions how the interaction between seed traits and digestive strategies affect the germinability of seeds following waterbird-mediated dispersal. We exposed seeds of 30 wetland plant species to the main digestive processes in the dabbling duck digestive system: mechanical, chemical and intestinal digestion. These were simulated by 1) a pressure test and scarification treatment, 2) incubation in simulated gastric juice, and 3) incubation in intestinal contents of culled mallards (Anas platyrhynchos). We evaluated their separate and combined effects on seed germination, and identified the role of seed size and seed coat traits in resisting the digestive forces. Seeds were generally resistant to separate digestive processes, but highly sensitive to a combination. Resistance to mechanical break-down was reduced by up to 80% by chemical pre-treatment, especially for seeds with permeable coats. Scarified seeds were 12–17% more vulnerable to chemical and intestinal digestive processes than undamaged seeds. Large seeds and seeds with thin, permeable coats were particularly sensitive to chemical and intestinal digestion. These results indicate that efficient digestion of seeds requires multiple digestive processes. The gizzard, responsible for mechanical digestion, plays a key role in seed survival. Omnivorous birds, which have relatively light gizzards compared to pure herbivores or granivores, are thus most likely to disperse seeds successfully. Regardless of digestive strategy, small seeds with tough seed coats are most resistant to digestion and may be adapted to endozoochorous dispersal by waterbirds. PMID:29614085

Interactions between seed traits and digestive processes determine the germinability of bird-dispersed seeds.

PubMed

Kleyheeg, Erik; Claessens, Mascha; Soons, Merel B

2018-01-01

Waterbirds disperse a wide range of plant seeds via their guts, promoting biotic connectivity between isolated habitat patches. However, the intensity of digestive forces encountered by seeds, and therefore their potential to survive digestive tract passage, varies within and between waterbird species. Here, we investigate under controlled conditions how the interaction between seed traits and digestive strategies affect the germinability of seeds following waterbird-mediated dispersal. We exposed seeds of 30 wetland plant species to the main digestive processes in the dabbling duck digestive system: mechanical, chemical and intestinal digestion. These were simulated by 1) a pressure test and scarification treatment, 2) incubation in simulated gastric juice, and 3) incubation in intestinal contents of culled mallards (Anas platyrhynchos). We evaluated their separate and combined effects on seed germination, and identified the role of seed size and seed coat traits in resisting the digestive forces. Seeds were generally resistant to separate digestive processes, but highly sensitive to a combination. Resistance to mechanical break-down was reduced by up to 80% by chemical pre-treatment, especially for seeds with permeable coats. Scarified seeds were 12-17% more vulnerable to chemical and intestinal digestive processes than undamaged seeds. Large seeds and seeds with thin, permeable coats were particularly sensitive to chemical and intestinal digestion. These results indicate that efficient digestion of seeds requires multiple digestive processes. The gizzard, responsible for mechanical digestion, plays a key role in seed survival. Omnivorous birds, which have relatively light gizzards compared to pure herbivores or granivores, are thus most likely to disperse seeds successfully. Regardless of digestive strategy, small seeds with tough seed coats are most resistant to digestion and may be adapted to endozoochorous dispersal by waterbirds.

Effects of stabilization and sludge properties in a combined process of anaerobic digestion and thermophilic aerobic digestion.

PubMed

Cheng, Jiehong; Kong, Feng; Zhu, Jun; Wu, Xiao

2015-01-01

A novel process of combining mesophilic (<35°C) anaerobic digestion with the thermophilic (55°C) aerobic digestion process (AN-TAD) was designed to stabilize sludge and economize aeration energy. Effects of stabilization and sludge properties for AN-TAD process were evaluated by batch experiments during a 25 d digestion period. The sludges digested by AN-TAD process achieved the requirements for Class-A sludge standard. The sludge at total solid (TS) 5.4% had the highest value of decay coefficient K(d(55)) at 0.1851 d(-1) among the three TS contents according to the first-order kinetics equation. Oxidation reduction potential at below 0 mV remained for sludges at TSs of 6.5%, 5.4%, and 4.6% for at least 15 d because of initial hydrolytic-acidification. Concentrations of nitrogen and phosphorus in sludges at TSs of 6.5%, 5.4%, and 4.6% gradually increased up to the highest values in the supernatant during the initial 13 d, causing low utilized value in land application as a fertilizer. Prolonging the retention time for more than 15 d was considered because soluble phosphorus precipitated in the solid phase. High content of soluble organic matters of the soluble chemical oxygen demand, protein, and polysaccharide in the supernatant caused deterioration in sludge dewaterability rates.

New concepts in anaerobic digestion processes: recent advances and biological aspects.

PubMed

Castellano-Hinojosa, Antonio; Armato, Caterina; Pozo, Clementina; González-Martínez, Alejandro; González-López, Jesús

2018-06-01

Waste treatment and the simultaneous production of energy have gained great interest in the world. In the last decades, scientific efforts have focused largely on improving and developing sustainable bioprocess solutions for energy recovery from challenging waste. Anaerobic digestion (AD) has been developed as a low-cost organic waste treatment technology with a simple setup and relatively limited investment and operating costs. Different technologies such as one-stage and two-stage AD have been developed. The viability and performance of these technologies have been extensively reported, showing the supremacy of two-stage AD in terms of overall energy recovery from biomass under different substrates, temperatures, and pH conditions. However, a comprehensive review of the advantages and disadvantages of these technologies is still lacking. Since microbial ecology is critical to developing successful AD, many studies have shown the structure and dynamics of archaeal and bacterial communities in this type of system. However, the role of Eukarya groups remains largely unknown to date. In this review, we provide a comprehensive review of the role, abundance, dynamics, and structure of archaeal, bacterial, and eukaryal communities during the AD process. The information provided could help researchers to select the adequate operational parameters to obtain the best performance and biogas production results.

The effect of feed composition on anaerobic co-digestion of animal-processing by-products.

PubMed

Hidalgo, D; Martín-Marroquín, J M; Corona, F

2018-06-15

Four streams and their mixtures have been considered for anaerobic co-digestion, all of them generated during pig carcasses processing or in related industrial activities: meat flour (MF), process water (PW), pig manure (PM) and glycerin (GL). Biochemical methane potential assays were conducted at 37 °C to evaluate the effects of the substrate mix ratio on methane generation and process behavior. The results show that the co-digestion of these products favors the anaerobic fermentation process when limiting the amount of meat flour in the mixture to co-digest, which should not exceed 10%. The ratio of other tested substrates is less critical, because different mixtures reach similar values of methane generation. The presence in the mixture of process water contributes to a quick start of the digester, something very interesting when operating an industrial reactor. The analysis of the fraction digested reveals that the four analyzed streams can be, a priori, suitable for agronomic valorization once digested. Copyright © 2017. Published by Elsevier Ltd.

Anaerobic digestion of food waste: A review focusing on process stability.

PubMed

Li, Lei; Peng, Xuya; Wang, Xiaoming; Wu, Di

2018-01-01

Food waste (FW) is rich in biomass energy, and increasing numbers of national programs are being established to recover energy from FW using anaerobic digestion (AD). However process instability is a common operational issue for AD of FW. Process monitoring and control as well as microbial management can be used to control instability and increase the energy conversion efficiency of anaerobic digesters. Here, we review research progress related to these methods and identify existing limitations to efficient AD; recommendations for future research are also discussed. Process monitoring and control are suitable for evaluating the current operational status of digesters, whereas microbial management can facilitate early diagnosis and process optimization. Optimizing and combining these two methods are necessary to improve AD efficiency. Copyright © 2017 Elsevier Ltd. All rights reserved.

Leachate properties as indicators of methane production process in MSW anaerobic digestion bioreactor landfill

NASA Astrophysics Data System (ADS)

Zeng, Yunmin; Wang, Li'ao; Xu, Tengtun; Li, Jiaxiang; Song, Xue; Hu, Chaochao

2018-03-01

In this paper, bioreactor was used to simulate the municipal solid waste (MSW) biodegradation process of landfill, tracing and testing trash methanogenic process and characteristics of leachate during anaerobic digestion, exploring the relationship between the two processes, aiming to screen out the indicators that can predict the methane production process of anaerobic digestion, which provides the support for real-time adjustment of technological parameters of MSW anaerobic digestion system and ensures the efficient operation of bioreactor landfill. The results showed that MSW digestion gas production rate constant is 0.0259 1/d, biogas production potential is 61.93 L/kg. The concentration of TN in leachate continued to increase, showing the trend of nitrogen accumulation. "Ammonia poisoning" was an important factor inhibiting waste anaerobic digestion gas production. In the anaerobic digestion system, although pH values of leachate can indicate methane production process to some degree, there are obvious lagging behind, so it cannot be used as indicator alone. The TOC/TN value of leachate has a certain indication on the stability of the methane production system. When TOC/TN value was larger than12, anaerobic digestion system was stable along with normal production of biogas. However, when TOC/TN value was lower than 12, the digestive system is unstable and the gas production is small. In the process of anaerobic digestion, the synthesis and transformation of valeric acid is more active. HAc/HVa changed greatly and had obvious inflection points, from which methane production period can be predicted.

[Anaerobic digestion of lignocellulosic biomass with animal digestion mechanisms].

PubMed

Wu, Hao; Zhang, Pan-Yue; Guo, Jian-Bin; Wu, Yong-Jie

2013-02-01

Lignocellulosic material is the most abundant renewable resource in the earth. Herbivores and wood-eating insects are highly effective in the digestion of plant cellulose, while anaerobic digestion process simulating animal alimentary tract still remains inefficient. The digestion mechanisms of herbivores and wood-eating insects and the development of anaerobic digestion processes of lignocellulose were reviewed for better understanding of animal digestion mechanisms and their application in design and operation of the anaerobic digestion reactor. Highly effective digestion of lignocellulosic materials in animal digestive system results from the synergistic effect of various digestive enzymes and a series of physical and biochemical reactions. Microbial fermentation system is strongly supported by powerful pretreatment, such as rumination of ruminants, cellulase catalysis and alkali treatment in digestive tract of wood-eating insects. Oxygen concentration gradient along the digestive tract may stimulate the hydrolytic activity of some microorganisms. In addition, the excellent arrangement of solid retention time, digesta flow and end product discharge enhance the animal digestion of wood cellulose. Although anaerobic digestion processes inoculated with rumen microorganisms based rumen digestion mechanisms were developed to treat lignocellulose, the fermentation was more greatly limited by the environmental conditions in the anaerobic digestion reactors than that in rumen or hindgut. Therefore, the anaerobic digestion processes simulating animal digestion mechanisms can effectively enhance the degradation of wood cellulose and other organic solid wastes.

Comparison of start-up strategies and process performance during semi-continuous anaerobic digestion of sugarcane filter cake co-digested with bagasse.

PubMed

Janke, Leandro; Leite, Athaydes F; Nikolausz, Marcell; Radetski, Claudemir M; Nelles, Michael; Stinner, Walter

2016-02-01

The anaerobic digestion of sugarcane filter cake and the option of co-digestion with bagasse were investigated in a semi-continuous feeding regime to assess the main parameters used for large-scale process designing. Moreover, fresh cattle manure was considered as alternative inoculum for the start-up of biogas reactors in cases where digestate from a biogas plant would not be available in remote rural areas. Experiments were carried out in 6 lab-scale semi-continuous stirred-tank reactors at mesophilic conditions (38±1°C) while the main anaerobic digestion process parameters monitored. Fresh cattle manure demonstrated to be appropriate for the start-up process. However, an acclimation period was required due to the high initial volatile fatty acids concentration (8.5gL(-1)). Regardless the mono-digestion of filter cake presented 50% higher biogas yield (480mLgVS(-1)) than co-digestion with bagasse (320mLgVS(-1)) during steady state conditions. A large-scale co-digestion system would produce 58% more biogas (1008m(3)h(-1)) than mono-digestion of filter cake (634m(3)h(-1)) due to its higher biomass availability for biogas conversion. Considering that the biogas production rate was the technical parameter that displayed the most relevant differences between the analyzed substrate options (0.99-1.45m(3)biogasm(3)d(-1)). The decision of which substrate option should be implemented in practice would be mainly driven by the available construction techniques, since economically efficient tanks could compensate the lower biogas production rate of co-digestion option. Copyright © 2015 Elsevier Ltd. All rights reserved.

Impact of processing on the digestibility of milk

USDA-ARS?s Scientific Manuscript database

Processing of milk by homogenization and pasteurization causes changes in the milk proteins and fats, but there is little information about whether these changes affect milk digestibility. In this study, whole and skim milk samples were processed and compared to raw milk after all samples had underg...

Innovative treatment system for digester liquor using anammox process.

PubMed

Furukawa, Kenji; Inatomi, Yasuhiko; Qiao, Sen; Quan, Lai; Yamamoto, Taichi; Isaka, Kazuichi; Sumino, Tatsuo

2009-11-01

This study demonstrated that partial nitritation using nitrifying activated sludge entrapped in a polyethylene glycol (PEG) gel carrier, as a pretreatment to anammox process, could be successfully applied to digester liquor of biogas plant at a nitrogen loading rate of 3.0 kg-N/m(3)/d. The nitritation process produced an effluent with a NO(2)-N/NH(4)-N ratio between 1.0 and 1.4, which was found to be suitable for the subsequent anammox process. A high SS concentration (2000-3000 mg/l) in the digester liquor did not affect partial nitritation treatment performances. Effluent from this partial nitritation reactor was successfully treated in the anammox reactor using anammox sludge entrapped in the PEG gel carrier with T-N removal rates of greater than 4.0 kg-N/m(3)/d. Influent BOD and SS contents did not inhibit anammox activity of the anammox gel carrier. The combination of partial nitritation and anammox reactors using PEG entrapped nitrifying and anammox bacteria was shown to be effective for the removal of high concentration ammonium in the digester liquor of a biogas plant.

Microbial community related to lysozyme digestion process for boosting waste activated sludge biodegradability.

PubMed

Xin, Xiao-Dong; He, Jun-Guo; Qiu, Wei; Tang, Jian; Liu, Tian-Tian

2015-01-01

Waste activated sludge from a lab-scale sequencing batch reactor was used to investigate the potential relation of microbial community with lysozyme digestion process for sludge solubilization. The results showed the microbial community shifted conspicuously as sludge suffered lysozyme digestion. Soluble protein and polysaccharide kept an increasing trend in solution followed with succession of microbial community. The rise of lysozyme dosage augmented the dissimilarity among communities in various digested sludge. A negative relationship presented between community diversity and lysozyme digestion process under various lysozyme/TS from 0 to 240min (correlation coefficient R(2) exceeded 0.9). Pareto-Lorenz curves demonstrated that microbial community tended to be even with sludge disintegration process by lysozyme. Finally, with diversity (H) decrease and community distribution getting even, the SCOD/TCOD increased steadily in solution which suggested the sludge with high community diversity and uneven population distribution might have tremendous potential for improving their biodegradability by lysozyme digestion. Copyright © 2014 Elsevier Ltd. All rights reserved.

Aerobic Digestion. Biological Treatment Process Control. Instructor's Guide.

ERIC Educational Resources Information Center

Klopping, Paul H.

This unit on aerobic sludge digestion covers the theory of the process, system components, factors that affect the process performance, standard operational concerns, indicators of steady-state operations, and operational problems. The instructor's guide includes: (1) an overview of the unit; (2) lesson plan; (3) lecture outline (keyed to a set of…

Review of enhanced processes for anaerobic digestion treatment of sewage sludge

NASA Astrophysics Data System (ADS)

Liu, Xinyuan; Han, Zeyu; Yang, Jie; Ye, Tianyi; Yang, Fang; Wu, Nan; Bao, Zhenbo

2018-02-01

Great amount of sewage sludge had been produced each year, which led to serious environmental pollution. Many new technologies had been developed recently, but they were hard to be applied in large scales. As one of the traditional technologies, anaerobic fermentation process was capable of obtaining bioenergy by biogas production under the functions of microbes. However, the anaerobic process is facing new challenges due to the low fermentation efficiency caused by the characteristics of sewage sludge itself. In order to improve the energy yield, the enhancement technologies including sewage sludge pretreatment process, co-digestion process, high-solid digestion process and two-stage fermentation process were widely studied in the literatures, which were introduced in this article.

Evaluating the toxicity of food processing wastes as co-digestion substrates with dairy manure.

PubMed

Lisboa, Maria Sol; Lansing, Stephanie

2014-07-01

Studies have shown that including food waste as a co-digestion substrate in the anaerobic digestion of livestock manure can increase energy production. However, the type and inclusion rate of food waste used for co-digestion need to be carefully considered in order to prevent adverse conditions in the digestion environment. This study determined the effect of increasing the concentration (2%, 5%, 15% and 30%, by volume) of four food-processing wastes (meatball, chicken, cranberry and ice cream processing wastes) on methane production. Anaerobic toxicity assay (ATA) and specific methanogenic activity (SMA) tests were conducted to determine the concentration at which each food waste became toxic to the digestion environment. Decreases in methane production were observed at concentrations above 5% for all four food waste substrates, with up to 99% decreases in methane production at 30% food processing wastes (by volume). Copyright © 2014 Elsevier Ltd. All rights reserved.

Techniques for quantitative LC-MS/MS analysis of protein therapeutics: advances in enzyme digestion and immunocapture.

PubMed

Fung, Eliza N; Bryan, Peter; Kozhich, Alexander

2016-04-01

LC-MS/MS has been investigated to quantify protein therapeutics in biological matrices. The protein therapeutics is digested by an enzyme to generate surrogate peptide(s) before LC-MS/MS analysis. One challenge is isolating protein therapeutics in the presence of large number of endogenous proteins in biological matrices. Immunocapture, in which a capture agent is used to preferentially bind the protein therapeutics over other proteins, is gaining traction. The protein therapeutics is eluted for digestion and LC-MS/MS analysis. One area of tremendous potential for immunocapture-LC-MS/MS is to obtain quantitative data where ligand-binding assay alone is not sufficient, for example, quantitation of antidrug antibody complexes. Herein, we present an overview of recent advance in enzyme digestion and immunocapture applicable to protein quantitation.

Studying the effect of microwave heating on the digestion process and identification of proteins.

PubMed

Devi, Shobha; Wu, Bo-Hung; Chu, Pei-Yu; Liu, Yue-Pei; Wu, Hsin-Lin; Ho, Yen-Peng

2017-02-01

The impact of microwave irradiation on the in-solution digestion processes and the detection limit of proteins are systematically studied. Kinetic processes of many peptides produced through the trypsin digestion of various proteins under microwave heating at 50°C were investigated with MALDI-MS. This study also examines the detection limits and digestion completeness of individual proteins under microwave heating at 50°C and at different time intervals (1, 5 and 30 min) using LC-MS. We conclude that if the peptides without missed cleavage dictate the detection limit, conventional digestion will lead to a better detection limit. The detection limit may not differ between the microwave and conventional heating if the peptides with missed cleavage sites and strong intensity are formed at the very early stage (i.e., less than 1 min) and are not further digested throughout the entire digestion process. The digestion of Escherichia coli lysate was compared under conventional and short time (microwave) conditions. The number of proteins identified under conventional heating exceeded that obtained from microwave heating over heating periods less than 5 min. The overall results show that the microwave-assisted digestion is not complete. Although the sequence coverage might be better, the detection limit might be worse than that under conventional heating. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Rapid microscale in-gel processing and digestion of proteins using surface acoustic waves.

PubMed

Kulkarni, Ketav P; Ramarathinam, Sri H; Friend, James; Yeo, Leslie; Purcell, Anthony W; Perlmutter, Patrick

2010-06-21

A new method for in-gel sample processing and tryptic digestion of proteins is described. Sample preparation, rehydration, in situ digestion and peptide extraction from gel slices are dramatically accelerated by treating the gel slice with surface acoustic waves (SAWs). Only 30 minutes total workflow time is required for this new method to produce base peak chromatograms (BPCs) of similar coverage and intensity to those observed for traditional processing and overnight digestion. Simple set up, good reproducibility, excellent peptide recoveries, rapid turnover of samples and high confidence protein identifications put this technology at the fore-front of the next generation of proteomics sample processing tools.

Effect of hybrid, maturity, and mechanical processing of corn silage on intake and digestibility by beef cattle.

PubMed

Andrae, J G; Hunt, C W; Pritchard, G T; Kennington, L R; Harrison, J H; Kezar, W; Mahanna, W

2001-09-01

A study involving a 2 x 2 x 2 factorial arrangement of treatments was conducted to evaluate effects of hybrid (Pioneer 3335 and 3489), maturity (half milkline and blacklayer), and mechanical processing (field chopper with and without on-board rollers engaged) on intake and digestibility of corn silage. Forty Angus steers (322 +/- 5.2 kg BW) were assigned to the eight silage treatments (five steers per treatment) and individually fed using electronic gates. Diets consisted of 60% corn silage and 40% chopped alfalfa hay (DM basis). Following a 5-d adaptation period, intake was measured for 7 d and subsequently fecal samples were collected for 5 d. Chromic oxide (5 g/d) was fed beginning 7 d before fecal sample collection and digestibility was determined by the ratio of Cr in the feed and feces. Steers were reallocated to treatments and these procedures were repeated, providing 10 observations per treatment. In addition, all silages were ruminally incubated in six mature cows for 0, 8, 16, 24, 48, and 96 h to determine extent and rate of DM, starch, NDF, and ADF disappearance. Processing increased DMI of hybrid 3489 but did not affect DMI of hybrid 3335 (hybrid x processing; P < 0.06). Total tract digestibility of DM, starch, NDF, and ADF decreased (P < 0.01) as plant maturity increased. Maturity tended to decrease starch digestibility more for hybrid 3489 than for hybrid 3335 (hybrid x maturity; P < 0.10). Processing increased (P < 0.01) starch digestibility but decreased (P < 0.01) NDF and ADF digestibility, resulting in no processing effect on DM digestibility. There was a numerical trend for processing to increase starch digestibility more for latethan for early-maturity corn silage (maturity x processing; P = 0.11). Processing increased in situ rates of DM and starch disappearance and maturity decreased in situ disappearance rates of starch and fiber. These data indicate that hybrid, maturity, and processing all affect corn silage digestibility. Mechanical

Digestive Diseases

MedlinePlus

... cells and provide energy. This process is called digestion. Your digestive system is a series of hollow organs joined ... are also involved. They produce juices to help digestion. There are many types of digestive disorders. The ...

High pressure processing of meat: effects on ultrastructure and protein digestibility.

PubMed

Kaur, Lovedeep; Astruc, Thierry; Vénien, Annie; Loison, Olivier; Cui, Jian; Irastorza, Marion; Boland, Mike

2016-05-18

The effects of high pressure processing (HPP, at 175 and 600 MPa) on the ultrastructure and in vitro protein digestion of bovine longissimus dorsi muscle meat were studied. HPP caused a significant change in the visual appearance and texture of the meat subjected to HPP at 600 MPa so that it appeared similar to cooked meat, unlike the meat subjected to HPP at 175 MPa that showed no significant visible change in the colour and texture compared to the raw meat. The muscles were subjected to digestion under simulated gastric conditions for 1 h and then under simulated small-intestinal conditions for a further 2 h. The digests were analysed using gel electrophoresis (SDS-PAGE) and ninhydrin assay for amino N. The effect of the acid conditions of the stomach alone was also investigated. Reduced SDS-PAGE results showed that pepsin-digested (60 min) HPP meats showed fewer proteins or peptides of high molecular weight than the pepsin-digested untreated meat, suggesting more breakdown of the parent proteins in HPP-treated meats. This effect was more pronounced in the muscles treated at 600 MPa. These results are in accordance with microscopy results, which showed greater changes in the myofibrillar structure after simulated gastric digestion of the sample processed at 600 MPa than at 175 MPa. Transmission electron microscopy also showed the presence of protein aggregates in the former sample, resulting probably from protein denaturation of sarcoplasmic proteins, in the subcellular space and between myofibrils; along with cell contraction (similar to that caused by heating) in the former.

Nanobiocatalysis for protein digestion in proteomic analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Jungbae; Kim, Byoung Chan; Lopez-Ferrer, Daniel

2010-02-01

The process of protein digestion is a critical step for successful protein identification in the bottom-up proteomic analysis. To substitute the present practice of in-solution protein digestion, which is long, tedious, and difficult to automate, a lot of efforts have been dedicated for the development of a rapid, recyclable and automated digestion system. Recent advances of nanobiocatalytic approaches have improved the performance of protein digestion by using various nanomaterials such as nanoporous materials, magnetic nanoparticles, and polymer nanofibers. Especially, the unprecedented success of trypsin stabilization in the form of trypsin-coated nanofibers, showing no activity decrease under repeated uses for onemore » year and retaining good resistance to proteolysis, has demonstrated its great potential to be employed in the development of automated, high-throughput, and on-line digestion systems. This review discusses recent developments of nanobiocatalytic approaches for the improved performance of protein digestion in speed, detection sensitivity, recyclability, and trypsin stability. In addition, we also introduce the protein digestions under unconventional energy inputs for protein denaturation and the development of microfluidic enzyme reactors that can benefit from recent successes of these nanobiocatalytic approaches.« less

Effects of coffee processing residues on anaerobic microorganisms and corresponding digestion performance.

PubMed

Rojas-Sossa, Juan Pablo; Murillo-Roos, Mariana; Uribe, Lidieth; Uribe-Lorio, Lorena; Marsh, Terence; Larsen, Niels; Chen, Rui; Miranda, Alberto; Solís, Kattia; Rodriguez, Werner; Kirk, Dana; Liao, Wei

2017-12-01

The objective of this study was to delineate the effects of different coffee processing residues on the anaerobic microbes and corresponding digestion performance. The results elucidated that mucilage-rich feed enhanced the accumulation of methanogens, which consequently led to better digestion performance of biogas production. Fifty percent more methane and up to 3 times more net energy (heat and electricity) output were achieved by the digestion of the mucilage-rich feed (M3). The microbial community and statistical analyses further elucidated that different residues in the feed had significant impact on microbial distribution and correspondingly influenced the digestion performance. Copyright © 2017 Elsevier Ltd. All rights reserved.

Foaming phenomenon in bench-scale anaerobic digesters.

PubMed

Siebels, Amanda M; Long, Sharon C

2013-04-01

The Madison Metropolitan Sewerage District (The District) in Madison, Wisconsin has been experiencing seasonal foaming in their anaerobic biosolids digesters, which has occurred from mid-November to late June for the past few years. The exact cause(s) of foaming is unknown. Previous research findings are unclear as to whether applications of advanced anaerobic digestion processes reduce the foaming potential of digesters. The object of this study was to investigate how configurations of thermophilic and acid phase-thermophilic anaerobic digestion would affect foaming at the bench-scale level compared to single stage mesophilic digestion for The District. Bench-scale anaerobic digesters were fed with a 4 to 4.5% by dry weight of solids content blend of waste activated sludge (WAS) and primary sludge from The District. Foaming potential was monitored using Alka-Seltzer and aeration foaming tests. The bench-scale acid phase-thermophilic digester had a higher foaming potential than the bench-scale mesophilic digester. These results indicate that higher temperatures increase the foaming potential of the bench-scale anaerobic digesters. The bench-scale acid phase-thermophilic digesters had a greater percent (approximately 5 to 10%) volatile solids destruction and a greater percent (approximately 5 to 10%) total solids destruction when compared to the bench-scale mesophilic digester. Overall, for the full-scale foaming experienced by The District, it appears that adding an acid phase or switching to thermophilic digestion would not alleviate The District's foaming issues.

Citrus essential oils and their influence on the anaerobic digestion process: an overview.

PubMed

Ruiz, B; Flotats, X

2014-11-01

Citrus waste accounts for more than half of the whole fruit when processed for juice extraction. Among valorisation possibilities, anaerobic digestion for methane generation appears to be the most technically feasible and environmentally friendly alternative. However, citrus essential oils can inhibit this biological process. In this paper, the characteristics of citrus essential oils, as well as the mechanisms of their antimicrobial effects and potential adaptation mechanisms are reviewed. Previous studies of anaerobic digestion of citrus waste under different conditions are presented; however, some controversy exists regarding the limiting dosage of limonene for a stable process (24-192 mg of citrus essential oil per liter of digester and day). Successful strategies to avoid process inhibition by citrus essential oils are based either on recovery or removal of the limonene, by extraction or fungal pre-treatment respectively. Copyright © 2014 Elsevier Ltd. All rights reserved.

Effects of processing method and solute interactions on pepsin digestibility of cooked proso millet flour.

PubMed

Gulati, Paridhi; Sabillón, Luis; Rose, Devin J

2018-07-01

Previous studies have reported a substantial decline in in vitro digestibility of proso millet protein upon cooking. In this study, several processing techniques and cooking solutions were tested with the objective of preventing the loss in pepsin digestibility. Proso millet flour was subjected to the following processing techniques: high pressure processing (200 and 600 MPa for 5 and 20 min); germination (96 h); fermentation (48 h); roasting (dry heating); autoclaving (121 °C, 3 h), and treatment with transglutaminase (160 mg/g protein, 37 °C, 2 h). To study the interaction of millet proteins with solutes, millet flour was heated with sucrose (3-7 M); NaCl (2-6 M); and CaCl 2 (0.5-3 M). All processing treatments failed to prevent the loss in pepsin digestibility except germination and treatment with transglutaminase, which resulted in 23 and 39% increases in digestibility upon cooking, respectively, when compared with unprocessed cooked flours. Heating in concentrated solutions of sucrose and NaCl were effective in preventing the loss in pepsin digestibility, an effect that was attributed to a reduction in water activity (a w ). CaCl 2 was also successful in preventing the loss in digestibility but its action was similar to chaotrops like urea. Thus, a combination of enzymatic modification and cooking of millet flour with either naturally low a w substances or edible sources of chaotropic ions may be useful in processing of proso millet for development of novel foods without loss in digestibility. However, more research is required to determine optimum processing conditions. Copyright © 2018 Elsevier Ltd. All rights reserved.

Advanced glycation endproducts form during ovalbumin digestion in the presence of fructose: Inhibition by chlorogenic acid.

PubMed

Bains, Yasmin; Gugliucci, Alejandro; Caccavello, Russell

2017-07-01

One mechanism by which fructose could exert deleterious effects is through intestinal formation and absorption of pro-inflammatory advanced glycation endproducts via the Maillard reaction. We employed simulated stomach and duodenum digestion of ovalbumin (OVA) to test the hypothesis that advanced glycation endproducts (AGEs) are formed by fructose during simulated digestion of a ubiquitous food protein under model physiological conditions. OVA was subjected to simulated gastric and intestinal digestion using standard models, in presence of fructose or glucose (0-100mM). Peptide fractions were analyzed by fluorescence spectroscopy and intensity at Excitation: λ370nm, Emission: λ 440nm. AGE adducts formed between fructose and OVA, evidenced by the peptide fractions (<5kDa) at times (30min) and concentration ranges (10mM) plausibly found in the intestines, whereas no reaction occurs with glucose. The reaction was inhibited by chlorogenic acid at concentrations compatible with those found in the gut. The reaction was also inhibited by aminoguanidine, a specific antiglycation agent. Our study showed fructose-AGE formation on a ubiquitous dietary protein under model physiological conditions. Our study also suggests ways to decrease the damage: enteral fructose-AGE formation may be partially inhibited by co-intake of beverages, fruits and vegetables with concentrations of phenolics high enough to serve as anti-glycation agents. Copyright © 2017 Elsevier B.V. All rights reserved.

Nutrient digestibility of broiler feeds containing different levels of variously processed rice bran stored for different periods.

PubMed

Mujahid, A; Asif, M; ul Haq, I; Abdullah, M; Gilani, A H

2003-09-01

Nutrient digestibility of broiler feeds containing different levels of variously processed rice bran stored for varying periods was determined. A total of 444 Hubbard male chicks were used to conduct four trials. Each trial was carried out on 111 chicks to determine digestibility of 36 different feeds. Chicks of 5 wk age were fed feeds containing raw, roasted, and extruded rice bran treated with antioxidant, Bianox Dry (0, 125, 250 g/ton), stored for a periods of 0, 4, 8, and 12 mo and used at levels of 0, 10, 20, and 30% in feeds. Digestibility coefficients for fat and fiber of feeds were determined. Increasing storage periods of rice bran significantly reduced the fat digestibility of feed, whereas no difference in fiber digestibility was observed. Processing of rice bran by extrusion cooking significantly increased digestibility of fat even used at higher levels in broiler feeds. Interaction of storage, processing, and levels was significant for fat digestibility. Treatments of rice bran by different levels of antioxidant had no effect on digestibility of fat and fiber when incorporated in broiler feed.

Modification in digestive processing strategies to reduce toxic trace metal uptake in a marine bivalve

DOE Office of Scientific and Technical Information (OSTI.GOV)

Decho, A.W.; Luoma, S.N.

1994-12-31

Bivalves possess two major digestion pathways for processing food particles: a rapid ``intestinal`` pathway where digestion is largely extracellular; and a slower ``glandular`` pathway where digestion is largely intracellular. The slower glandular pathway often results in more efficient absorption of carbon but also more efficient uptake of certain metals (e.g. Cr associated with bacteria). In the bivalve Potamocorbula amurensis, large portions (> 90%) of bacteria are selectively routed to the glandular pathway. This results in efficient C uptake but also efficient uptake of associated Cr. The authors further determined if prolonged exposure to Cr-contaminated bacteria would result in high Crmore » uptake by animals or whether mechanisms exist to reduce Cr exposure and uptake. Bivalves were exposed to natural food + added bacteria (with or without added Cr) for a 6-day period, then pulse-chase experiments were conducted to quantify digestive processing and % absorption efficiencies (%AE) of bacterial Cr. Bivalves compensate at low (2--5 ug/g sed) Cr by reducing overall food ingestion, while digestive processing of food remains statistically similar to controls. At high Cr (200--500 ug/g sed) there are marked decreases in % bacteria processed by glandular digestion. This results in lower overall %AE of Cr. The results suggest that bivalves under natural conditions might balance efficient carbon sequestration against avoiding uptake of potentially toxic metals associated the food.« less

Kinetic study of anaerobic digestion of fruit-processing wastewater in immobilized-cell bioreactors.

PubMed

Borja, R; Banks, C J

1994-08-01

The kinetics of the anaerobic digestion of a fruit-processing wastewater [chemical oxygen demand (COD) = 5.1 g/l] were investigated. Laboratory experiments were carried out in bioreactors containing supports of different chemical composition and features, namely bentonite and zeolite (aluminum silicates), sepiolite and saponite (magnesium silicates) and polyurethane foam, to which the microorganisms responsible for the process adhered. The influence of the support medium on the kinetics was compared with a control digester with suspended biomass. Assuming the overall anaerobic digestion process conforms to first-order kinetics, the specific rate constant, K0, was determined for each of the experimental reactors. The average values obtained were: 0.080 h-1 (bentonite); 0.103 h-1 (zeolite); 0.180 h-1 (sepiolite); 0.198 h-1 (saponite); 0.131 h-1 (polyurethane); and 0.037 h-1 (control). The results indicate that the support used to immobilize the micro-organisms had a marked influence on the digestion process; the results were significant at the 95% confidence level. Methanogenic activity increased linearly with COD, with the saponite and sepiolite supports showing the highest values. The yield coefficient of methane was 270 ml of methane (under standard temperature and pressure conditions)/g of COD. The average elimination of COD was 89.5%.

The imaging and modelling of the physical processes involved in digestion and absorption.

PubMed

Schulze, K S

2015-02-01

The mechanical activity of the gastro-intestinal tract serves to store, propel and digest food. Contractions disperse particles and transform solids and secretions into the two-phase slurry called chyme; movements of the intestine deliver nutrients to mucosal sites of absorption, and from the submucosa into the lymphatic and portal venous circulation. Colonic motor activity helps to extract fluid and electrolytes from chyme and to compound and compact luminal debris into faeces for elimination. We outline how dynamic imaging by ultrasound and magnetic resonance can demonstrate intestinal flow processes critical to digestion like mixing, dilution, swelling, dispersion and elution. Computational fluid mechanics enables a numerical rendition of the forces promoting digestion: pressure and flow fields, the shear stresses dispersing particles or the effectiveness of bolus mixing can be calculated. These technologies provide new insights into the mechanical processes that promote digestion and absorption. © 2014 This article is a U.S. Government work and is in the public domain in the USA.

Combined thermophilic aerobic process and conventional anaerobic digestion: effect on sludge biodegradation and methane production.

PubMed

Dumas, C; Perez, S; Paul, E; Lefebvre, X

2010-04-01

The efficiency of hyper-thermophilic (65 degrees Celsius) aerobic process coupled with a mesophilic (35 degrees Celsius) digester was evaluated for the activated sludge degradation and was compared to a conventional mesophilic digester. For two Sludge Retention Time (SRT), 21 and 42 days, the Chemical Oxygen Demand (COD) solubilisation and biodegradation processes, the methanisation yield and the aerobic oxidation were investigated during 180 days. The best results were obtained at SRT of 44 days; the COD removal yield was 30% higher with the Mesophilic Anaerobic Digestion/Thermophilic Aerobic Reactor (MAD-TAR) co-treatment. An increase of the sludge intrinsic biodegradability is also observed (20-40%), showing that the unbiodegradable COD in mesophilic conditions becomes bioavailable. However, the methanisation yield was quite similar for both processes at a same SRT. Finally, such a process enables to divide by two the volume of digester with an equivalent efficiency. Copyright 2009 Elsevier Ltd. All rights reserved.

Enhancement of proteolytic enzyme activity excreted from Bacillus stearothermophilus for a thermophilic aerobic digestion process.

PubMed

Kim, Young-Kee; Bae, Jin-Hye; Oh, Byung-Keun; Lee, Won Hong; Choi, Jeong-Woo

2002-04-01

Proteolysis is one of the main enzymatic reactions involved in waste activated sludge (WAS) digestion. In this study, proteases excreted from Bacillus stearothermophilus (ATCC 31197) were classified, and an enhancement of protease activity was achieved using economical chemical additives for WAS digestion. Proteases excreted from B. stearothermophilus were classified into two families: serine and metallo-proteases. Various metal ions were investigated as additives which could potentially enhance protease activity. It was observed that Ca2+ and Fe2+ could markedly activate these enzymes. These results were applied to thermophilic aerobic digestion (TAD) of industrial WAS using B. stearothermophilus. The addition of these divalent ions enhanced the degradation performance of the TAD process in terms of reducing the total suspended solids (TSSs), the dissolved organic carbon (DOC) content, and the intracellular and extracellular protein concentrations. The best result, with respect to protein reduction in a digestion experiment, was obtained by the addition of 2 mM Ca2+. Therefore, a proposed TAD process activated by calcium addition can be successfully used for industrial and municipal WAS digestion to the upgrading of TAD process performance.

Impact of food processing on rye product properties and their in vitro digestion.

PubMed

Johansson, Daniel P; Gutiérrez, José L Vázquez; Landberg, Rikard; Alminger, Marie; Langton, Maud

2018-06-01

Rye products have been reported to elicit postprandial insulin and glucose responses which may be beneficial for prevention of type-2 diabetes. However, mechanisms underlying variations in responses related to processing techniques are not fully understood. Five differently processed rye products (sourdough-fermented bread, fermented and unfermented crispbread, extrusion-cooked rye, and porridge) and refined wheat bread were characterised. Two in vitro methods, a dynamic method simulating digestion in the stomach and small intestine and a static method, simulating conditions in the stomach were used to determine viscosity development, structural changes and release of glucose during digestion. Structural and compositional differences induced by processing influenced product digestion. Gastric disintegration and digesta particle size were related to characteristics of the starch/protein matrix, while digesta viscosity was reduced due to fibre degradation during fermentation. More cohesive boluses were associated with slower glucose release. Sourdough fermentation increased amylose leakage and appeared to inhibit starch hydrolysis despite low digesta viscosity and rapid disintegration. The net release of glucose during digestion of foods is determined by several factors which may vary in their importance depending on product specific properties.

Mechanisms of starch digestion by α-amylase-Structural basis for kinetic properties.

PubMed

Dhital, Sushil; Warren, Frederick J; Butterworth, Peter J; Ellis, Peter R; Gidley, Michael J

2017-03-24

Recent studies of the mechanisms determining the rate and extent of starch digestion by α-amylase are reviewed in the light of current widely-used classifications for (a) the proportions of rapidly-digestible (RDS), slowly-digestible (SDS), and resistant starch (RS) based on in vitro digestibility, and (b) the types of resistant starch (RS 1,2,3,4…) based on physical and/or chemical form. Based on methodological advances and new mechanistic insights, it is proposed that both classification systems should be modified. Kinetic analysis of digestion profiles provides a robust set of parameters that should replace the classification of starch as a combination of RDS, SDS, and RS from a single enzyme digestion experiment. This should involve determination of the minimum number of kinetic processes needed to describe the full digestion profile, together with the proportion of starch involved in each process, and the kinetic properties of each process. The current classification of resistant starch types as RS1,2,3,4 should be replaced by one which recognizes the essential kinetic nature of RS (enzyme digestion rate vs. small intestinal passage rate), and that there are two fundamental origins for resistance based on (i) rate-determining access/binding of enzyme to substrate and (ii) rate-determining conversion of substrate to product once bound.

Behavior of cellulose-degrading bacteria in thermophilic anaerobic digestion process.

PubMed

Syutsubo, K; Nagaya, Y; Sakai, S; Miya, A

2005-01-01

Previously, we found that the newly isolated Clostridium sp. strain JC3 became the dominant cellulose-degrading bacterium in thermophilic methanogenic sludge. In the present study, the behavior of strain JC3 in the thermophilic anaerobic digestion process was investigated quantitatively by molecular biological techniques. A cellulose-degrading experiment was conducted at 55 degrees C with a 9.5 L of anaerobic baffled reactor having three compartments (Nos. 1, 2, 3). Over 80% of the COD input was converted into methane when 2.5 kgCOD m(-3) d(-1) was loaded for an HRT of 27 days. A FISH probe specific for strain JC3 was applied to sludge samples harvested from the baffled reactor. Consequently, the ratio of JC3 cells to DAPI-stained cells increased from below 0.5% (undetectable) to 9.4% (compartment 1), 13.1% (compartment 2) and 21.6% (compartment 3) at day 84 (2.5 kgCOD m(-3)d(-1)). The strain JC3 cell numbers determined by FISH correlated closely with the cellulose-degrading methanogenic activities of retained sludge. A specific primer set targeting the cellulase gene (cellobiohydrolaseA: cbhA) of strain JC3 was designed and applied to digested sludge for treating solid waste such as coffee grounds, wastepaper, garbage, cellulose and so on. The strain JC3 cell numbers determined by quantitative PCR correlated closely with the cellulose-sludge loading of the thermophilic digester. Strain JC3 is thus important in the anaerobic hydrolysis of cellulose in thermophilic anaerobic digestion processes.

Malting process optimization for protein digestibility enhancement in finger millet grain.

PubMed

Hejazi, Sara Najdi; Orsat, Valérie

2016-04-01

Finger millet (Eleusine coracana) is a nutritious, gluten-free, and drought resistant cereal containing high amounts of protein, carbohydrate, and minerals. However, bio-availability of these nutrients is restricted due to the presence of an excessive level of anti-nutrient components, mainly phytic acid, tannin, and oxalate. It has been shown that a well-designed malting/germination process can significantly reduce these anti-nutrients and consequently enhance the nutrient availability. In the present study, the effects of two important germination factors, duration and temperature, on the enhancement of in-vitro protein digestibility of finger millet were thoroughly investigated and optimized. Based on a central composite design, the grains were germinated for 24, 36, and 48 h at 22, 26, and 30 °C. For all factor combinations, protein, peptide, phytic acid, tannin, and oxalate contents were evaluated and digestibility was assessed. It was shown that during the malting/germinating process, both temperature and duration factors significantly influenced the investigated quantities. Germination of finger millet for 48 h at 30 °C increased protein digestibility from 74 % (for native grain) up to 91 %. Besides, it notably decreased phytic acid, tannin, and oxalate contents by 45 %, 46 %, and 29 %, respectively. Linear correlations between protein digestibility and these anti-nutrients were observed.

Characteristics of sludge reduction in an integrated pretreatment and aerobic digestion process.

PubMed

Hwang, S; Jang, H; Lee, M; Song, J; Kim, S

2006-01-01

In this study, integrated pretreatments and aerobic digestion processes were investigated in order to provide a feasible alternative that can achieve effective sludge reduction. An ozone treatment in the presence of ionic manganese, a catalyst, increased the sludge reduction ratio three times higher than that of a single ozonation, presumably due to an increase in OH radical production. The ozone treatment yielded the effective sludge reduction ratio with an increasing ozone dosage, and an effective dosage of the catalyst was found to be 4 mg-Mn/g-TS. When a mechanical pretreatment and an ozone/catalyst were applied in a series, the integrated process, even at a half mechanical intensity and a half level of ozone dosage, showed higher and faster sludge reduction than each single process did. In addition, the integrated pretreatment process showed the highest dewaterability of the treated sludges. A ratio of sludge cake generation, which was newly introduced to quantify overall performance of sludge treatment processes, showed that the integrated pretreatment followed by the aerobic digestion yielded approximately a half of the sludge cake volume compared to the single aerobic digestion. Therefore, the integrated pretreatment can be a feasible method for the effective reduction of total suspended solid and the final volume.

Anaerobic Digestion and its Applications

EPA Science Inventory

Anaerobic digestion is a natural biological process. The initials "AD" may refer to the process of anaerobic digestion, or the built systems of anaerobic digesters. While there are many kinds of digesters, the biology is basically the same for all. Anaerobic digesters are built...

Improved ADM1 model for anaerobic digestion process considering physico-chemical reactions.

PubMed

Zhang, Yang; Piccard, Sarah; Zhou, Wen

2015-11-01

The "Anaerobic Digestion Model No. 1" (ADM1) was modified in the study by improving the bio-chemical framework and integrating a more detailed physico-chemical framework. Inorganic carbon and nitrogen balance terms were introduced to resolve the discrepancies in the original bio-chemical framework between the carbon and nitrogen contents in the degraders and substrates. More inorganic components and solids precipitation processes were included in the physico-chemical framework of ADM1. The modified ADM1 was validated with the experimental data and used to investigate the effects of calcium ions, magnesium ions, inorganic phosphorus and inorganic nitrogen on anaerobic digestion in batch reactor. It was found that the entire anaerobic digestion process might exist an optimal initial concentration of inorganic nitrogen for methane gas production in the presence of calcium ions, magnesium ions and inorganic phosphorus. Copyright © 2015 Elsevier Ltd. All rights reserved.

Advanced Applications of Robotics in Digestive Surgery

PubMed Central

Patriti, Alberto; Addeo, Pietro; Buchs, Nicolas; Casciola, Luciano; Morel, Philippe

2011-01-01

Laparoscopy is widely recognized as feasible and safe approach to many oncologic and benign digestive conditions and is associated with an improved early outcome. Robotic surgery promises to overcome intrinsic limitations of laparoscopic surgery by a three-dimensional view and wristed instruments widening indications for a minimally invasive approach. To date, the more interesting applications of robotic surgery are those operations restricted to one abdominal quadrant and requiring a fine dissection and digestive reconstruction. While robot-assisted rectal and gastric surgery are becoming well-accepted options among the surgical community, applications of robotics in hepato-biliary and pancreatic surgery are still debated. PMID:23905029

Fatty acid profiles of in vitro digested processed milk

USDA-ARS?s Scientific Manuscript database

Digestion of milkfat releases some of the long-chain (18-carbon) fatty acids (FA) that can provide health benefits to the consumer, yet because they are found in small amounts and can be difficult to identify, there is limited information on the effects that common fluid milk processing may have on ...

Ammonia removal in food waste anaerobic digestion using a side-stream stripping process.

PubMed

Serna-Maza, A; Heaven, S; Banks, C J

2014-01-01

Three 35-L anaerobic digesters fed on source segregated food waste were coupled to side-stream ammonia stripping columns and operated semi-continuously over 300 days, with results in terms of performance and stability compared to those of a control digester without stripping. Biogas was used as the stripping medium, and the columns were operated under different conditions of temperature (55, 70, 85 °C), pH (unadjusted and pH 10), and RT (2-5 days). To reduce digester TAN concentrations to a useful level a high temperature (≥70 °C) and a pH of 10 were needed; under these conditions 48% of the TAN was removed over a 138-day period without any detrimental effects on digester performance. Other effects of the stripping process were an overall reduction in digestate organic nitrogen-containing fraction compared to the control and a recovery in the acetoclastic pathway when TAN concentration was 1770±20 mg kg(-1). Copyright © 2013 Elsevier Ltd. All rights reserved.

Digestibility of gluten proteins is reduced by baking and enhanced by starch digestion

PubMed Central

Pan, Xiaoyan; Bellido, Vincent; Toole, Geraldine A.; Gates, Fred K.; Wickham, Martin S. J.; Shewry, Peter R.; Bakalis, Serafim; Padfield, Philip; Mills, E. N. Clare

2015-01-01

Scope Resistance of proteins to gastrointestinal digestion may play a role in determining immune‐mediated adverse reactions to foods. However, digestion studies have largely been restricted to purified proteins and the impact of food processing and food matrices on protein digestibility is poorly understood. Methods and results Digestibility of a total gliadin fraction (TGF), flour (cv Hereward), and bread was assessed using in vitro batch digestion with simulated oral, gastric, and duodenal phases. Protein digestion was monitored by SDS‐PAGE and immunoblotting using monoclonal antibodies specific for celiac‐toxic sequences (QQSF, QPFP) and starch digestion by measuring undigested starch. Whereas the TGF was rapidly digested during the gastric phase the gluten proteins in bread were virtually undigested and digested rapidly during the duodenal phase only if amylase was included. Duodenal starch digestion was also slower in the absence of duodenal proteases. Conclusion The baking process reduces the digestibility of wheat gluten proteins, including those containing sequences active in celiac disease. Starch digestion affects the extent of protein digestion, probably because of gluten‐starch complex formation during baking. Digestion studies using purified protein fractions alone are therefore not predictive of digestion in complex food matrices. PMID:26202208

Combined mesophilic anaerobic and thermophilic aerobic digestion process: effect on sludge degradation and variation of sludge property.

PubMed

Cheng, Jiehong; Ji, Yuehong; Kong, Feng; Chen, Xian

2013-12-01

One-stage autothermal thermophilic aerobic digestion (ATAD) is effective for the reduction of volatile solids (VSs) and pathogen in sewage sludges. A novel process of combining mesophilic (<35 °C) anaerobic digestion with a thermophilic (55 °C) aerobic digestion process (AN/TAD) occurred in a one-stage digester, which was designed for aeration energy savings. The efficiency of sludge degradation and variation of sludge properties by batch experiments were evaluated for the AN/TAD digester with an effective volume of 23 L for 30 days compared with conventional thermophilic aerobic digestion (TAD). The AN/TAD system can efficiently achieve sludge stabilization on the 16th day with a VS removal rate of 38.1 %. The AN/TAD system was operated at lower ORP values in a digestion period with higher contents of total organic compounds, volatile fatty acids, protein, and polysaccharide in the soluble phase than those of the TAD system, which can rapidly decreased and had low values in the late period of digestion for the AN/TAD system. In the AN/TAD system, intracellular substances had lysis because of initial hydrolytic acidification.

Development of an advanced anaerobic digester design and a kinetic model for biogasification of water hyacinth/sludge blends

DOE Office of Scientific and Technical Information (OSTI.GOV)

Srivastava, V.; Fannin, K.F.; Biljetina, R.

1986-07-01

The Institute of Gas Technology (IGT) conducted a comprehensive laboratory-scale research program to develop and optimize the anaerobic digestion process for producing methane from water hyacinth and sludge blends. This study focused on digester design and operating techniques, which gave improved methane yields and production rates over those observed using conventional digesters. The final digester concept and the operating experience was utilized to design and operate a large-scale experimentla test unit (ETU) at Walt Disney World, Florida. This paper describes the novel digester design, operating techniques, and the results obtained in the laboratory. The paper also discusses a kinetic modelmore » which predicts methane yield, methane production rate, and digester effluent solids as a function of retention time. This model was successfully utilized to predict the performance of the ETU. 15 refs., 6 figs., 6 tabs.« less

Multicenter retrospective analysis of systemic chemotherapy for advanced neuroendocrine carcinoma of the digestive system.

PubMed

Yamaguchi, Tomohiro; Machida, Nozomu; Morizane, Chigusa; Kasuga, Akiyoshi; Takahashi, Hideaki; Sudo, Kentaro; Nishina, Tomohiro; Tobimatsu, Kazutoshi; Ishido, Kenji; Furuse, Junji; Boku, Narikazu; Okusaka, Takuji

2014-09-01

This study analyzed outcomes of systemic chemotherapy for advanced neuroendocrine carcinoma (NEC) of the digestive system. Clinical data from 258 patients with unresectable or recurrent NEC of the gastrointestinal tract (GI) or hepato-biliary-pancreatic system (HBP), who received chemotherapy, were collected from 23 Japanese institutions and analyzed retrospectively. Patients had primary sites in the esophagus (n = 85), stomach (n = 70), small bowel (n = 6), colorectum (n = 31), hepato-biliary system (n = 31) and pancreas (n = 31). Median overall survival (OS) was 13.4 months the esophagus, 13.3 months for the stomach, 29.7 months for the small bowel, 7.6 months for the colorectum, 7.9 months for the hepato-biliary system and 8.5 months for the pancreas. Irinotecan plus cisplatin (IP) and etoposide plus cisplatin (EP) were most commonly selected for GI-NEC and HBP-NEC. For patients treated with IP/EP (n = 160/46), the response rate was 50/28% and median OS was 13.0/7.3 months. Multivariate analysis among patients treated with IP or EP showed that the primary site (GI vs HBP; hazard ratio [HR] 0.58, 95% confidence interval [CI] 0.35-0.97) and baseline serum lactate dehydrogenase levels (not elevated vs elevated; HR 0.65, 95% CI 0.46-0.94) were independent prognostic factors for OS, while the efficacy of IP was slightly better than for EP (HR 0.80, 95% CI 0.48-1.33; P = 0.389). IP and EP are the most common treatment regimens for NEC of the digestive system. HBP primary sites and elevated lactate dehydrogenase levels are unfavorable prognostic factors for survival. A randomized controlled trial is required to establish the appropriate chemotherapy regimen for advanced NEC of the digestive system. This study was registered at UMIN as trial number 000005176. © 2014 The Authors. Cancer Science published by Wiley Publishing Asia Pty Ltd on behalf of Japanese Cancer Association.

Digestibility of gluten proteins is reduced by baking and enhanced by starch digestion.

PubMed

Smith, Frances; Pan, Xiaoyan; Bellido, Vincent; Toole, Geraldine A; Gates, Fred K; Wickham, Martin S J; Shewry, Peter R; Bakalis, Serafim; Padfield, Philip; Mills, E N Clare

2015-10-01

Resistance of proteins to gastrointestinal digestion may play a role in determining immune-mediated adverse reactions to foods. However, digestion studies have largely been restricted to purified proteins and the impact of food processing and food matrices on protein digestibility is poorly understood. Digestibility of a total gliadin fraction (TGF), flour (cv Hereward), and bread was assessed using in vitro batch digestion with simulated oral, gastric, and duodenal phases. Protein digestion was monitored by SDS-PAGE and immunoblotting using monoclonal antibodies specific for celiac-toxic sequences (QQSF, QPFP) and starch digestion by measuring undigested starch. Whereas the TGF was rapidly digested during the gastric phase the gluten proteins in bread were virtually undigested and digested rapidly during the duodenal phase only if amylase was included. Duodenal starch digestion was also slower in the absence of duodenal proteases. The baking process reduces the digestibility of wheat gluten proteins, including those containing sequences active in celiac disease. Starch digestion affects the extent of protein digestion, probably because of gluten-starch complex formation during baking. Digestion studies using purified protein fractions alone are therefore not predictive of digestion in complex food matrices. © 2015 The Authors. Molecular Nutrition & Food Research published by Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Anaerobic digestion of food waste stabilized by lime mud from papermaking process.

PubMed

Zhang, Jishi; Wang, Qinqing; Zheng, Pengwei; Wang, Yusong

2014-10-01

The effects of lime mud from papermaking process (LMP) addition as buffer agent and inorganic nutrient on the anaerobic digestion stability of food waste (FW) were investigated under mesophilic conditions with the aim of avoiding volatile fatty acids accumulation, and inorganic elements deficiency. When LMP concentration ranged from 6.0 to 10g/L, the FW anaerobic digestion could maintain efficient and stable state. These advantages are attributed to the existence of Ca, Na, Mg, K, Fe, and alkaline substances that favor the methanogenic process. The highest CH4 yield of 272.8mL/g-VS was obtained at LMP and VS concentrations of 10.0 and 19.8g/L, respectively, with the corresponding lag-phase time of 3.84d and final pH of 8.4. The methanogens from residue digestates mainly consisted of Methanobrevibacter, coccus-type and sarcina-type methanogens with LMP addition compared to Methanobacteria in control. However, higher concentration of LMP inhibited methanogenic activities and methane production. Copyright © 2014 Elsevier Ltd. All rights reserved.

Involving Parents in the IEP Process. ERIC Digest E611.

ERIC Educational Resources Information Center

Smith, Stephen W.

This digest paper examines the special roles of parents of children with disabilities in planning for the education of their children and discusses how educators can work effectively with parents to create meaningful individualized education programs (IEPs). Barriers to parental participation in the IEP process are identified, including…

Aerobic composting of digested residue eluted from dry methane fermentation to develop a zero-emission process.

PubMed

Huang, Yu-Lian; Sun, Zhao-Yong; Zhong, Xiao-Zhong; Wang, Ting-Ting; Tan, Li; Tang, Yue-Qin; Kida, Kenji

2017-03-01

Digested residue remained at the end of a process for the production of fuel ethanol and methane from kitchen garbage. To develop a zero-emission process, the compostability of the digested residue was assessed to obtain an added-value fertilizer. Composting of the digested residue by adding matured compost and a bulking agent was performed using a lab-scale composting reactor. The composting process showed that volatile total solid (VTS) degradation mainly occurred during the first 13days, and the highest VTS degradation efficiency was about 27% at the end. The raw material was not suitable as a fertilizer due to its high NH 4 + and volatile fatty acids (VFAs) concentration. However, the composting process produced remarkable results; the physicochemical properties indicated that highly matured compost was obtained within 62days of the composting process, and the final N concentration, NO 3 - concentration, and the germination index (GI) at the end of the composting process was 16.4gkg -1 -TS, 9.7gkg -1 -TS, and 151%, respectively. Real-time quantitative PCR (qPCR) analysis of ammonia oxidizers indicated that the occurrence of nitrification during the composting of digested residue was attributed to the activity of ammonia-oxidizing bacteria (AOB). Copyright © 2017 Elsevier Ltd. All rights reserved.

The one-stage autothermal thermophilic aerobic digestion for sewage sludge treatment: stabilization process and mechanism.

PubMed

Liu, Shugen; Zhu, Nanwen; Li, Loretta Y

2012-01-01

Batch experiment was carried out in a simulated thermophilic aerobic digester to investigate the digestion process of one-stage autothermal thermophilic aerobic digester and to explore the sludge stabilization mechanism. Volatile solids removal was 38.4% at 408 h and 45.0% at 552 h. Chemical oxidation demand, total nitrogen, and ammonia nitrogen in supernatant increased rapidly up to 168 h, and all of them fluctuated moderately after 360 h. Volatile fatty acid (VFA) accumulated rapidly up to 24 to 168 h, then declined sharply, reaching a low concentration after 312 h. Propionic, iso-valeric, and iso-butyric acids, in addition to acetic acids, were also the major components of VFA. As the biochemical metabolic process was inhibited under oxygen-deficiency condition, the digestion system can produce acetic, propionic, butyric acids and other VFA constituents to meet the demand for NAD(+) and maximize ATP generation. The ORP affected the VFA production and depletion as well as sulfate levels. Copyright © 2011 Elsevier Ltd. All rights reserved.

Lab-scale demonstration of recuperative thickening technology for enhanced biogas production and dewaterability in anaerobic digestion processes.

PubMed

Cobbledick, Jeffrey; Aubry, Nicholas; Zhang, Victor; Rollings-Scattergood, Sasha; Latulippe, David R

2016-05-15

There is growing interest in the use of high performance anaerobic digestion (AD) processes for the production of biogas at wastewater treatment facilities to offset the energy demands associated with wastewater treatment. Recuperative thickening (RT) is a promising technique which involves recycling a portion of the digested solids back to the incoming feed. In general there exists a significant number of knowledge gaps in the field of RT because the studies that have been conducted to date have almost exclusively occurred in pilot plant or full scale trials; this approach greatly limits the amount of process optimization that can be done in a given trial. In this work, a detailed and comprehensive study of RT was conducted at the lab scale; two custom designed digesters (capacity = 1.5 L) were operated in parallel with one acting as a 'control' digester and the other operating under a semi-batch RT mode. There was no significant change in biogas methane composition for the two digesters, however the RT digester had an average biogas productivity over two times higher than the control one. It was found that the recycling of the polymer flocculant back into the RT digester resulted in a significant improvement in dewatering performance. At the highest polymer concentration tested, the capillary suction time (CST) values for flocculated samples for the RT digester were over 6 times lower than the corresponding values for the control digester. Thus, there exists an opportunity to decrease the overall consumption of polymer flocculants through judicious selection of the dose of polymer flocculant that is used both for the thickening and end-stage dewatering steps in RT processes. Copyright © 2016 Elsevier Ltd. All rights reserved.

A fuzzy logic approach to control anaerobic digestion.

PubMed

Domnanovich, A M; Strik, D P; Zani, L; Pfeiffer, B; Karlovits, M; Braun, R; Holubar, P

2003-01-01

One of the goals of the EU-Project AMONCO (Advanced Prediction, Monitoring and Controlling of Anaerobic Digestion Process Behaviour towards Biogas Usage in Fuel Cells) is to create a control tool for the anaerobic digestion process, which predicts the volumetric organic loading rate (Bv) for the next day, to obtain a high biogas quality and production. The biogas should contain a high methane concentration (over 50%) and a low concentration of components toxic for fuel cells, e.g. hydrogen sulphide, siloxanes, ammonia and mercaptanes. For producing data to test the control tool, four 20 l anaerobic Continuously Stirred Tank Reactors (CSTR) are operated. For controlling two systems were investigated: a pure fuzzy logic system and a hybrid-system which contains a fuzzy based reactor condition calculation and a hierachial neural net in a cascade of optimisation algorithms.

Recent development of anaerobic digestion processes for energy recovery from wastes.

PubMed

Nishio, Naomichi; Nakashimada, Yutaka

2007-02-01

Anaerobic digestion leads to the overall gasification of organic wastewaters and wastes, and produces methane and carbon dioxide; this gasification contributes to reducing organic matter and recovering energy from organic carbons. Here, we propose three new processes and demonstrate the effectiveness of each process. By using complete anaerobic organic matter removal process (CARP), in which diluted wastewaters such as sewage and effluent from a methane fermentation digester were treated under anaerobic condition for post-treatment, the chemical oxygen demand (COD) in wastewater was decreased to less than 20 ppm. The dry ammonia-methane two-stage fermentation process (Am-Met process) is useful for the anaerobic treatment of nitrogen-rich wastes such as waste excess sludge, cow feces, chicken feces, and food waste without the dilution of the ammonia produced by water or carbon-rich wastes. The hydrogen-methane two-stage fermentation (Hy-Met process), in which the hydrogen produced in the first stage is used for a fuel cell system to generate electricity and the methane produced in the second stage is used to generate heat energy to heat the two reactors and satisfy heat requirements, is useful for the treatment of sugar-rich wastewaters, bread wastes, and biodiesel wastewaters.

Reviewing the anaerobic digestion and co-digestion process of food waste from the perspectives on biogas production performance and environmental impacts.

PubMed

Chiu, Sam L H; Lo, Irene M C

2016-12-01

In this paper, factors that affect biogas production in the anaerobic digestion (AD) and anaerobic co-digestion (coAD) processes of food waste are reviewed with the aim to improve biogas production performance. These factors include the composition of substrates in food waste coAD as well as pre-treatment methods and anaerobic reactor system designs in both food waste AD and coAD. Due to the characteristics of the substrates used, the biogas production performance varies as different effects are exhibited on nutrient balance, inhibitory substance dilution, and trace metal element supplement. Various types of pre-treatment methods such as mechanical, chemical, thermal, and biological methods are discussed to improve the rate-limiting hydrolytic step in the digestion processes. The operation parameters of a reactor system are also reviewed with consideration of the characteristics of the substrates. Since the environmental awareness and concerns for waste management systems have been increasing, this paper also addresses possible environmental impacts of AD and coAD in food waste treatment and recommends feasible methods to reduce the impacts. In addition, uncertainties in the life cycle assessment (LCA) studies are also discussed.

Molecular disassembly of rice and lotus starches during thermal processing and its effect on starch digestibility.

PubMed

Wang, Shujun; Sun, Yue; Wang, Jinrong; Wang, Shuo; Copeland, Les

2016-02-01

The molecular disassembly of starch during thermal processing is a major determinant for the susceptibility of starch to enzymatic digestion. In the present study, the effects of thermal processing on the disassembly of the granular structure and the in vitro enzymatic digestibility of rice and lotus starches were investigated. After heating at 50 °C, rice and lotus starches did not show significant changes in granular morphology, long-range crystallinity and short-range molecular order. As the temperature increased to 60 °C, rice starch underwent a partial gelatinization followed by an incomplete disruption of granular morphology, crystallites and molecular order. In contrast, lotus starch was almost completely gelatinized at 60 °C. At 70 °C or higher, both starches were fully gelatinized with complete disruption of the micro and macro structures. Our results show that gelatinization greatly increased the in vitro enzymatic digestibility of both starches, but that the degree of disassembly of the starch structure during thermal processing was not a major determinant of the digestibility of gelatinized starch.

Implementation and process analysis of pilot scale multi-phase anaerobic fermentation and digestion of faecal sludge in Ghana

PubMed Central

Shih, Justin; Fanyin-Martin, Ato; Taher, Edris; Chandran, Kartik

2017-01-01

Background.  In Ghana, faecal sludge (FS) from on-site sanitation facilities is often discharged untreated into the environment, leading to significant insults to environmental and human health. Anaerobic digestion offers an attractive pathway for FS treatment with the concomitant production of energy in the form of methane. Another innovative option includes separating digestion into acidogenesis (production of volatile fatty acids (VFA)) and methanogenesis (production of methane), which could ultimately facilitate the production of an array of biofuels and biochemicals from the VFA. This work describes the development, implementation and modeling based analysis of a novel multiphase anaerobic fermentation-digestion process aimed at FS treatment in Kumasi, Ghana.  Methods.  A pilot-scale anaerobic fermentation process was implemented at the Kumasi Metropolitan Assembly’s Oti Sanitary Landfill Site at Adanse Dompoase.  The process consisted of six 10 m reactors in series, which were inoculated with bovine rumen and fed with fecal sludge obtained from public toilets.  The performance of the fermentation process was characterized in terms of both aqueous and gaseous variables representing the conversion of influent organic carbon to VFA as well as CH 4.  Using the operating data, the first-ever process model for FS fermentation and digestion was developed and calibrated, based on the activated sludge model framework. Results and Conclusions.  This work represents one of the first systematic efforts at integrated FS characterization and process modeling to enable anaerobic fermentation and digestion of FS. It is shown that owing to pre-fermentation of FS in public septage holding tanks, one could employ significantly smaller digesters (lower capital costs) or increased loading capabilities for FS conversion to biogas or VFA. Further, using the first-ever calibrated process model for FS fermentation and digestion presented herein, we expect improved and more

Implementation and process analysis of pilot scale multi-phase anaerobic fermentation and digestion of faecal sludge in Ghana.

PubMed

Shih, Justin; Fanyin-Martin, Ato; Taher, Edris; Chandran, Kartik

2017-11-06

Background.  In Ghana, faecal sludge (FS) from on-site sanitation facilities is often discharged untreated into the environment, leading to significant insults to environmental and human health. Anaerobic digestion offers an attractive pathway for FS treatment with the concomitant production of energy in the form of methane. Another innovative option includes separating digestion into acidogenesis (production of volatile fatty acids (VFA)) and methanogenesis (production of methane), which could ultimately facilitate the production of an array of biofuels and biochemicals from the VFA. This work describes the development, implementation and modeling based analysis of a novel multiphase anaerobic fermentation-digestion process aimed at FS treatment in Kumasi, Ghana.  Methods.  A pilot-scale anaerobic fermentation process was implemented at the Kumasi Metropolitan Assembly's Oti Sanitary Landfill Site at Adanse Dompoase.  The process consisted of six 10 m reactors in series, which were inoculated with bovine rumen and fed with fecal sludge obtained from public toilets.  The performance of the fermentation process was characterized in terms of both aqueous and gaseous variables representing the conversion of influent organic carbon to VFA as well as CH 4 .  Using the operating data, the first-ever process model for FS fermentation and digestion was developed and calibrated, based on the activated sludge model framework. Results and Conclusions.  This work represents one of the first systematic efforts at integrated FS characterization and process modeling to enable anaerobic fermentation and digestion of FS. It is shown that owing to pre-fermentation of FS in public septage holding tanks, one could employ significantly smaller digesters (lower capital costs) or increased loading capabilities for FS conversion to biogas or VFA. Further, using the first-ever calibrated process model for FS fermentation and digestion presented herein, we expect improved and more

Effect of acid detergent fiber in hydrothermally pretreated sewage sludge on anaerobic digestion process

NASA Astrophysics Data System (ADS)

Takasaki, Rikiya; Yuan, Lee Chang; Kamahara, Hirotsugu; Atsuta, Youichi; Daimon, Hiroyuki

2017-10-01

Hydrothermal treatment is one of the pre-treatment method for anaerobic digestion. The application of hydrothermal treatment to sewage sludge of wastewater treatment plant has been succeeded to enhance the biogas production. The purpose of this study is to quantitatively clarify the effect of hydrothermal treatment on anaerobic digestion process focusing on acid detergent fiber (ADF) in sewage sludge, which is low biodegradability. The hydrothermal treatment experiment was carried out for 15 minutes between 160 °C and 200 °C respectively. The ADF content was decreased after hydrothermal treatment compared with untreated sludge. However, ADF content was increased when raising the treatment temperature from 160 °C to 200 °C. During batch anaerobic digestion experiment, untreated and treated sludge were examined for 10 days under 38 °C, and all samples were fed once based on volatile solids of samples. From batch anaerobic digestion experiment, as ADF content in sewage sludge increased, the total biogas production decreased. It was found that ADF content in sewage sludge influence on anaerobic digestion. Therefore, ADF could be one of the indicator to evaluate the effect of hydrothermal treatment to sewage sludge on anaerobic digestion.

Nitrogen removal from digested slurries using a simplified ammonia stripping technique.

PubMed

Provolo, Giorgio; Perazzolo, Francesca; Mattachini, Gabriele; Finzi, Alberto; Naldi, Ezio; Riva, Elisabetta

2017-11-01

This study assessed a novel technique for removing nitrogen from digested organic waste based on a slow release of ammonia that was promoted by continuous mixing of the digestate and delivering a continuous air stream across the surface of the liquid. Three 10-day experiments were conducted using two 50-L reactors. In the first two, nitrogen removal efficiencies were evaluated from identical digestates maintained at different temperatures (30°C and 40°C). At the start of the first experiment, the digestates were adjusted to pH 9 using sodium hydroxide, while in the second experiment pH was not adjusted. The highest ammonia removal efficiency (87%) was obtained at 40°C with pH adjustment. However at 40°C without pH adjustment, removal efficiencies of 69% for ammonia and 47% for total nitrogen were obtained. In the third experiment two different digestates were tested at 50°C without pH adjustment. Although the initial chemical characteristics of the digestates were different in this experiment, the ammonia removal efficiencies were very similar (approximately 85%). Despite ammonia removal, the pH increased in all experiments, most likely due to carbon dioxide stripping that was promoted by temperature and mixing. The technique proved to be suitable for removing nitrogen following anaerobic digestion of livestock manure because effective removal was obtained at natural pH (≈8) and 40°C, common operating conditions at typical biogas plants that process manure. Furthermore, the electrical energy requirement to operate the process is limited (estimated to be 3.8kWhm -3 digestate). Further improvements may increase the efficiency and reduce the processing time of this treatment technique. Even without these advances slow-rate air stripping of ammonia is a viable option for reducing the environmental impact associated with animal manure management. Copyright © 2017 Elsevier Ltd. All rights reserved.

In vitro starch digestibility, pasting and textural properties of mung bean: effect of different processing methods.

PubMed

Kaur, Maninder; Sandhu, Kawaljit Singh; Ahlawat, RavinderPal; Sharma, Somesh

2015-03-01

Mung bean was subjected to different processing conditions (soaking, germination, cooking and autoclaving) and their textural, pasting and in vitro starch digestibility characteristics were studied. A significant reduction in textural properties (hardness, cohesiveness, gumminess and chewiness) after cooking and autoclaving treatment of mung bean was observed. Flours made from differently processed mung bean showed significant differences (P < 0.05) in their pastin g characteristics. Peak and final viscosity were the highest for flour from germinated mung bean whereas those made from autoclaved mung bean showed the lowest value. in vitro starch digestibility of mung bean flours was assessed enzymatically using modified Englyst method and the parameters studied were readily digestible starch (RDS), slowly digestible starch (SDS), resistant starch (RS) and total starch (TS) content. Various processing treatments increased the RDS contents of mung bean, while the SDS content was found to be the highest for soaked and the lowest for the autoclaved sample. Germinated sample showed higher amount of digestible starch (RDS + SDS) as compared to raw and soaked samples. Flours from raw and soaked samples showed significantly low starch hydrolysis rate at all the temperatures with total hydrolysis of 29.9 and 31.2 %, respectively at 180 min whereas cooked and autoclaved samples showed high hydrolysis rates with 50.2 and 53.8 % of these hydrolyzing within 30 min of hydrolysis.

Sequential anaerobic/aerobic digestion of waste activated sludge: analysis of the process performance and kinetic study.

PubMed

Tomei, M Concetta; Rita, Sara; Mininni, Giuseppe

2011-12-15

Sequential anaerobic-aerobic digestion was applied to waste activated sludge (WAS) of a full scale wastewater treatment plant. The study was performed with the objective of testing the sequential digestion process on WAS, which is characterized by worse digestibility in comparison with the mixed sludge. Process performance was evaluated in terms of biogas production, volatile solids (VS) and COD reduction, and patterns of biopolymers (proteins and polysaccharides) in the subsequent digestion stages. VS removal efficiency of 40%, in the anaerobic phase, and an additional removal of 26%, in the aerobic one, were observed. For total COD removal efficiencies of 35% and 25% for anaerobic and aerobic stage respectively, were obtained. Kinetics of VS degradation process was analyzed by assuming a first order equation with respect to VS concentration. Evaluated kinetic parameters were 0.44 ± 0.20 d(-1) and 0.25 ± 0.15 d(-1) for the anaerobic stage and aerobic stage, respectively. With regard to biopolymers, in the anaerobic phase the content of proteins and polysaccharides increased to 50% and 69%, respectively, whereas in the subsequent aerobic phase, a decrease of 71% for proteins and 67% for polysaccharides was observed. The average specific biogas production 0.74 m(3)/(kg VS destroyed), was in the range of values reported in the specialized literature for conventional anaerobic mesophilic WAS digestion. Copyright © 2011 Elsevier B.V. All rights reserved.

Impact of food processing and simulated gastrointestinal digestion on gliadin immunoreactivity in rolls.

PubMed

Brzozowski, Bartosz

2018-07-01

The enzymatic modification of wheat proteins during dough fermentation and its digestion as supported by peptidases of microbiological origin can result in the degradation of important peptides in the pathogenesis of coeliac disease. However, baking bread and the high temperature associated with this could change the physicochemical and immunological properties of proteins. Thermal changes in the spatial structure of proteins and their hydrolysis can lead to a masking or degrading of immunoreactive peptides. The addition of prolyl endopeptidase (PEP), comprising peptidases isolated from Lactobacillus acidophilus 5e2 (LA) or transglutaminase (TG) in the course of fermentation, decreases its immunoreactivity by 83.9%, 51.9% and 18.5%, respectively. An analysis of the fractional composition of gliadins revealed that γ- and ω-gliadins are the proteins most susceptible to enzymatic modification. Hydrolysis of wheat storage proteins with PEP and LA reduces the content of αβ-, γ- and ω-gliadins by 13.7%, 60.2% and 41.9% for PEP and by 22.1%, 43.5% and 36.9% for LA, respectively. Cross-linking of proteins with TG or their hydrolysis by PEP and LA peptidases during the process of forming wheat dough, followed by digesting bread samples with PEP and LA peptidases, decreases the immunoreactivity of bread hydrolysates from 2.4% to 0.02%. The content of peptide detected in polypeptide sequences is 263.4 ± 3.3, 30.9 ± 1.5 and 7.9 ± 0.4 mg kg -1 in samples of hydrolysates of bread digested with PEP, as produced from dough modified by TG, PEP and LA, respectively. Enzymatic pre-modification of proteins during the process of dough fermentation decreases their immunoreactive potential, such that fewer peptides recognised by R5 antibodies are released during the digestion process from the bread matrix. Immunoreactive peptides are degraded more effectively when digestive enzymes are supported by the addition of PEP. © 2017 Society of Chemical Industry. © 2017

Techno-economic evaluation of stillage treatment with anaerobic digestion in a softwood-to-ethanol process.

PubMed

Barta, Zsolt; Reczey, Kati; Zacchi, Guido

2010-09-15

Replacing the energy-intensive evaporation of stillage by anaerobic digestion is one way of decreasing the energy demand of the lignocellulosic biomass to the ethanol process. The biogas can be upgraded and sold as transportation fuel, injected directly into the gas grid or be incinerated on-site for combined heat and power generation. A techno-economic evaluation of the spruce-to-ethanol process, based on SO2-catalysed steam pretreatment followed by simultaneous saccharification and fermentation, has been performed using the commercial flow-sheeting program Aspen Plus™. Various process configurations of anaerobic digestion of the stillage, with different combinations of co-products, have been evaluated in terms of energy efficiency and ethanol production cost versus the reference case of evaporation. Anaerobic digestion of the stillage showed a significantly higher overall energy efficiency (87-92%), based on the lower heating values, than the reference case (81%). Although the amount of ethanol produced was the same in all scenarios, the production cost varied between 4.00 and 5.27 Swedish kronor per litre (0.38-0.50 euro/L), including the reference case. Higher energy efficiency options did not necessarily result in lower ethanol production costs. Anaerobic digestion of the stillage with biogas upgrading was demonstrated to be a favourable option for both energy efficiency and ethanol production cost. The difference in the production cost of ethanol between using the whole stillage or only the liquid fraction in anaerobic digestion was negligible for the combination of co-products including upgraded biogas, electricity and district heat.

Techno-economic evaluation of stillage treatment with anaerobic digestion in a softwood-to-ethanol process

PubMed Central

2010-01-01

Background Replacing the energy-intensive evaporation of stillage by anaerobic digestion is one way of decreasing the energy demand of the lignocellulosic biomass to the ethanol process. The biogas can be upgraded and sold as transportation fuel, injected directly into the gas grid or be incinerated on-site for combined heat and power generation. A techno-economic evaluation of the spruce-to-ethanol process, based on SO2-catalysed steam pretreatment followed by simultaneous saccharification and fermentation, has been performed using the commercial flow-sheeting program Aspen Plus™. Various process configurations of anaerobic digestion of the stillage, with different combinations of co-products, have been evaluated in terms of energy efficiency and ethanol production cost versus the reference case of evaporation. Results Anaerobic digestion of the stillage showed a significantly higher overall energy efficiency (87-92%), based on the lower heating values, than the reference case (81%). Although the amount of ethanol produced was the same in all scenarios, the production cost varied between 4.00 and 5.27 Swedish kronor per litre (0.38-0.50 euro/L), including the reference case. Conclusions Higher energy efficiency options did not necessarily result in lower ethanol production costs. Anaerobic digestion of the stillage with biogas upgrading was demonstrated to be a favourable option for both energy efficiency and ethanol production cost. The difference in the production cost of ethanol between using the whole stillage or only the liquid fraction in anaerobic digestion was negligible for the combination of co-products including upgraded biogas, electricity and district heat. PMID:20843330

Process performance of high-solids batch anaerobic digestion of sewage sludge.

PubMed

Liao, Xiaocong; Li, Huan; Cheng, Yingchao; Chen, Nan; Li, Chenchen; Yang, Yuning

2014-01-01

The characteristics of high-solids anaerobic digestion (AD) of sewage sludge were investigated by comparison with conventional low-solids processes. A series of batch experiments were conducted under mesophilic condition and the initial solid contents were controlled at four levels of 1.79%, 4.47%, 10.28% and 15.67%. During these experiments, biogas production, organic degradation and intermediate products were monitored. The results verified that high-solids batch AD of sewage sludge was feasible. Compared with the low-solids AD with solid contents of 1.79% or 4.47%, the high-solids processes decreased the specific biogas yield per gram of sludge volatile solids slightly, achieved the same organic degradation rate of about 40% within extended degradation time, but increased the volumetric biogas production rate and the treatment capability of digesters significantly. The blocked mass and energy transfer, the low substrate to inoculum rate and the excessive cumulative free ammonia were the main factors impacting the performance of high-solids batch AD.

ANL progress on the cooperation with CNEA for the Mo-99 production : base-side digestion process.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gelis, A. V.; Quigley, K. J.; Aase, S. B.

2004-01-01

Conversion from high-enriched uranium (HEU) to low-enriched uranium (LEU) targets for the Mo-99 production requires certain modifications of the target design, the digestion and the purification processes. ANL is assisting the Argentine Comision Nacional de Energia Atomica (CNEA) to overcome all the concerns caused by the conversion to LEU foil targets. A new digester with stirring system has been successfully applied for the digestion of the low burn-up U foil targets in KMnO4 alkaline media. In this paper, we report the progress on the development of the digestion procedure with stirring focusing on the minimization of the liquid radioactive waste.

Influence of processing and in vitro digestion on the allergic cross-reactivity of three mealworm species.

PubMed

van Broekhoven, Sarah; Bastiaan-Net, Shanna; de Jong, Nicolette W; Wichers, Harry J

2016-04-01

Edible insects are currently being evaluated as an alternative and more sustainable protein source for humans. The introduction of new food sources can lead to development of novel allergies. Because in the Western world, insects are unlikely to be consumed raw, it is important to know how processing and in vitro digestion might influence their allergenicity. Three edible mealworm species (Tenebrio molitor, Zophobas atratus and Alphitobius diaperinus) subjected to processing and in vitro digestion were analysed for IgE cross-reactivity. Immunoblot and MALDI-MS/MS analyses revealed that IgE from crustaceans or House dust mite (HDM) allergic patients showed cross-reactivity to mealworm tropomyosin or α-amylase, hexamerin 1B precursor and muscle myosin, respectively. Heat processing as well as in vitro digestion did diminish, but not eliminate, HDM or tropomyosin IgE cross-reactivity. Results show that individuals allergic to HDM or crustaceans might be at risk when consuming mealworms, even after heat processing. Copyright © 2015 Elsevier Ltd. All rights reserved.

Effect of processing on polyamine content and bioactive peptides released after in vitro gastrointestinal digestion of infant formulas.

PubMed

Gómez-Gallego, C; Recio, I; Gómez-Gómez, V; Ortuño, I; Bernal, M J; Ros, G; Periago, M J

2016-02-01

This study examined the influence of processing on polyamines and peptide release after the digestion of a commercial infant formula designed for children during the first months of life. Polyamine oxidase activity was not suppressed during the manufacturing process, which implicates that polyamine concentrations were reduced over time and during infant formula self-life. In gel electrophoresis, in vitro gastrointestinal digestion of samples with reduced amount of enzymes and time of digestion shows an increase in protein digestibility, reflected in the increase in nonprotein nitrogen after digestion and the disappearance of β-lactoglobulin and α-lactalbumin bands in gel electrophoresis. Depending on the sample, between 22 and 87 peptides were identified after gastrointestinal digestion. A peptide from β-casein f(98-105) with the sequence VKEAMAPK and antioxidant activity appeared in all of the samples. Other peptides with antioxidant, immunomodulatory, and antimicrobial activities were frequently found, which could have an effect on infant health. The present study confirms that the infant formula manufacturing process determines the polyamine content and peptidic profile after digestion of the infant formula. Because compositional dissimilarity between human milk and infant formula in polyamines and proteins could be responsible for some of the differences in health reported between breast-fed and formula-fed children, these changes must be taken into consideration because they may have a great effect on infant nutrition and development. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Hybrid alkali-hydrodynamic disintegration of waste-activated sludge before two-stage anaerobic digestion process.

PubMed

Grübel, Klaudiusz; Suschka, Jan

2015-05-01

The first step of anaerobic digestion, the hydrolysis, is regarded as the rate-limiting step in the degradation of complex organic compounds, such as waste-activated sludge (WAS). The aim of lab-scale experiments was to pre-hydrolyze the sludge by means of low intensive alkaline sludge conditioning before applying hydrodynamic disintegration, as the pre-treatment procedure. Application of both processes as a hybrid disintegration sludge technology resulted in a higher organic matter release (soluble chemical oxygen demand (SCOD)) to the liquid sludge phase compared with the effects of processes conducted separately. The total SCOD after alkalization at 9 pH (pH in the range of 8.96-9.10, SCOD = 600 mg O2/L) and after hydrodynamic (SCOD = 1450 mg O2/L) disintegration equaled to 2050 mg/L. However, due to the synergistic effect, the obtained SCOD value amounted to 2800 mg/L, which constitutes an additional chemical oxygen demand (COD) dissolution of about 35 %. Similarly, the synergistic effect after alkalization at 10 pH was also obtained. The applied hybrid pre-hydrolysis technology resulted in a disintegration degree of 28-35%. The experiments aimed at selection of the most appropriate procedures in terms of optimal sludge digestion results, including high organic matter degradation (removal) and high biogas production. The analyzed soft hybrid technology influenced the effectiveness of mesophilic/thermophilic anaerobic digestion in a positive way and ensured the sludge minimization. The adopted pre-treatment technology (alkalization + hydrodynamic cavitation) resulted in 22-27% higher biogas production and 13-28% higher biogas yield. After two stages of anaerobic digestion (mesophilic conditions (MAD) + thermophilic anaerobic digestion (TAD)), the highest total solids (TS) reduction amounted to 45.6% and was received for the following sample at 7 days MAD + 17 days TAD. About 7% higher TS reduction was noticed compared with the sample after 9

Towards a sustainable paradigm of waste-to-energy process: Enhanced anaerobic digestion of sludge with woody biochar

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shen, Yanwen; Linville, Jessica L.; Ignacio-de Leon, Patricia Anne A.

This study presents an integrated waste-to-energy process, using two waste streams, sludge generated from the municipal wastewater treatment plants (WWTPs) and biochar generated from the biomass gasification systems, to produce fungible biomethane and nutrient-rich digestate with fertilizer value. Two woody biochar, namely pinewood (PBC) and white oak biochar (WOBC) were used as additives during anaerobic digestion (AD) of WWTP sludge to enhance methane production at mesophilic and thermophilic temperatures. The PBC and WOBC have porous structure, large surface area and desirable chemical properties to be used as AD amendment material to sequester CO2 from biogas in the digester. The biochar-amendedmore » digesters achieved average methane content in biogas of up to 92.3% and 79.0%, corresponding to CO2 sequestration by up to 66.2% and 32.4% during mesophilic and thermophilic AD, respectively. Biochar addition enhanced process stability by increasing the alkalinity, but inhibitory effects were observed at high dosage. It also alleviated free ammonia inhibition by up to 10.5%. The biochar-amended digesters generated digestate rich in macro- and micronutrients including K (up to 300 m/L), Ca (up to 750 mg/L), Mg (up to 1800 mg/L) and Fe (up to 390 mg/L), making biochar-amended digestate a potential alternative used as agricultural lime fertilizer.« less

Advanced biorefinery in lower termite-effect of combined pretreatment during the chewing process

PubMed Central

2012-01-01

Background Currently the major barrier in biomass utilization is the lack of an effective pretreatment of plant cell wall so that the carbohydrates can subsequently be hydrolyzed into sugars for fermentation into fuel or chemical molecules. Termites are highly effective in degrading lignocellulosics and thus can be used as model biological systems for studying plant cell wall degradation. Results We discovered a combination of specific structural and compositional modification of the lignin framework and partial degradation of carbohydrates that occurs in softwood with physical chewing by the termite, Coptotermes formosanus, which are critical for efficient cell wall digestion. Comparative studies on the termite-chewed and native (control) softwood tissues at the same size were conducted with the aid of advanced analytical techniques such as pyrolysis gas chromatography mass spectrometry, attenuated total reflectance Fourier transform infrared spectroscopy and thermogravimetry. The results strongly suggest a significant increase in the softwood cellulose enzymatic digestibility after termite chewing, accompanied with utilization of holocellulosic counterparts and an increase in the hydrolysable capacity of lignin collectively. In other words, the termite mechanical chewing process combines with specific biological pretreatment on the lignin counterpart in the plant cell wall, resulting in increased enzymatic cellulose digestibility in vitro. The specific lignin unlocking mechanism at this chewing stage comprises mainly of the cleavage of specific bonds from the lignin network and the modification and redistribution of functional groups in the resulting chewed plant tissue, which better expose the carbohydrate within the plant cell wall. Moreover, cleavage of the bond between the holocellulosic network and lignin molecule during the chewing process results in much better exposure of the biomass carbohydrate. Conclusion Collectively, these data indicate the

Autoheated thermophilic aerobic digestion

DOE Office of Scientific and Technical Information (OSTI.GOV)

Deeny, K.; Hahn, H.; Leonhard, D.

1991-10-01

Autothermal thermophilic aerobic digestion (ATAD) is first and foremost a digestion process, the primary purpose of which is to decompose a portion of the waste organic solids generated from wastewater treatment. As a result of the high operating temperature, digestion is expected to occur within a short time period (6 days) and accomplish a high degree of pathogen reduction. ATAD systems are two-stage aerobic digestion processes that operate under thermophilic temperature conditions (40 to 80C) without supplemental heat. Like composting, the systems rely on the conservation of heat released during digestion itself to attain and sustain the desired operating temperature.more » Typical ATAD systems operate at 55C and may reach temperatures of 60 to 65C in the second-stage reactor. Perhaps because of the high operating temperature, this process has been referred to as Liquid Composting.' Major advantages associated with thermophilic operation include high biological reaction rates and a substantial degree of pathogen reduction.« less

Analysis of digester design concepts

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ashare, E.; Wilson, E. H.

1979-01-29

Engineering economic analyses were performed on various digester design concepts to determine the relative performance for various biomass feedstocks. A comprehensive literature survey describing the state-of-the-art of the various digestion designs is included. The digester designs included in the analyses are CSTR, plug flow, batch, CSTR in series, multi-stage digestion and biomethanation. Other process options investigated included pretreatment processes such as shredding, degritting, and chemical pretreatment, and post-digestion processes, such as dewatering and gas purification. The biomass sources considered include feedlot manure, rice straw, and bagasse. The results of the analysis indicate that the most economical (on a unit gasmore » cost basis) digester design concept is the plug flow reactor. This conclusion results from this system providing a high gas production rate combined with a low capital hole-in-the-ground digester design concept. The costs determined in this analysis do not include any credits or penalties for feedstock or by-products, but present the costs only for conversion of biomass to methane. The batch land-fill type digester design was shown to have a unit gas cost comparable to that for a conventional stirred tank digester, with the potential of reducing the cost if a land-fill site were available for a lower cost per unit volume. The use of chemical pretreatment resulted in a higher unit gas cost, primarily due to the cost of pretreatment chemical. A sensitivity analysis indicated that the use of chemical pretreatment could improve the economics provided a process could be developed which utilized either less pretreatment chemical or a less costly chemical. The use of other process options resulted in higher unit gas costs. These options should only be used when necessary for proper process performance, or to result in production of a valuable by-product.« less

Development of an efficient anaerobic co-digestion process for garbage, excreta, and septic tank sludge to create a resource recycling-oriented society.

PubMed

Sun, Zhao-Yong; Liu, Kai; Tan, Li; Tang, Yue-Qin; Kida, Kenji

2017-03-01

In order to develop a resource recycling-oriented society, an efficient anaerobic co-digestion process for garbage, excreta and septic tank sludge was studied based on the quantity of each biomass waste type discharged in Ooki machi, Japan. The anaerobic digestion characteristics of garbage, excreta and 5-fold condensed septic tank sludge (hereafter called condensed sludge) were determined separately. In single-stage mesophilic digestion, the excreta with lower C/N ratios yielded lower biogas volumes and accumulated higher volumes of volatile fatty acid (VFA). On the other hand, garbage allowed for a significantly larger volatile total solid (VTS) digestion efficiency as well as biogas yield by thermophilic digestion. Thus, a two-stage anaerobic co-digestion process consisting of thermophilic liquefaction and mesophilic digestion phases was proposed. In the thermophilic liquefaction of mixed condensed sludge and household garbage (wet mass ratio of 2.2:1), a maximum VTS loading rate of 24g/L/d was achieved. In the mesophilic digestion of mixed liquefied material and excreta (wet mass ratio of 1:1), biogas yield reached approximately 570ml/g-VTS fed with a methane content of 55% at a VTS loading rate of 1.0g/L/d. The performance of the two-stage process was evaluated by comparing it with a single-stage process in which biomass wastes were treated separately. Biogas production by the two-stage process was found to increase by approximately 22.9%. These results demonstrate the effectiveness of a two-stage anaerobic co-digestion process in enhancement of biogas production. Copyright © 2016 Elsevier Ltd. All rights reserved.

Change of the structure and the digestibility of myofibrillar proteins in Nanjing dry-cured duck during processing.

PubMed

Du, Xiaojing; Sun, Yangying; Pan, Daodong; Wang, Ying; Ou, Changrong; Cao, Jinxuan

2018-06-01

To investigate the change of bioavailability and structure of myofibrillar proteins during Nanjing dry-cured duck processing, carbonyl content, sulfhydryl (SH) group, disulfide (SS) group, sodium dodecyl sulfate polyacrylamide gel electrophoresis, surface hydrophobicity, secondary structures and in vitro digestibility were determined. During processing, carbonyl content and surface hydrophobicity increased; SH turned into SS group; α-helix turned into β-sheet and random coil fractions. Protein degradation occurred during dry-curing and drying-ripening stages. The in vitro digestibility of pepsin and pancreatic proteases increased during the salt curing stage and decreased during the drying-ripening stage. The increase of digestibility could be attributed to the mild oxidation, degradation and unfolding of proteins while the decrease of digestibility was related to the intensive oxidation and aggregation of proteins. Protein degradation was not a main factor of digestibility during the drying-ripening stage. Results demonstrated that the bioavailability loss of myofibrillar proteins in Nanjing dry-cured duck occurred during the stage of drying-ripening instead of curing. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Determination of the potential bioavailability of plant microRNAs using a simulated human digestion process.

PubMed

Philip, Anna; Ferro, Valerie A; Tate, Rothwelle J

2015-10-01

The "dietary xenomiR hypothesis" proposes that microRNAs (miRNAs) in foodstuffs survive transit through the mammalian gastrointestinal tract and pass into cells intact to affect gene regulation. However, debate continues as to whether dietary intake poses a feasible route for such exogenous gene regulators. Understanding on miRNA levels during pretreatments of human diet is essential to test their bioavailability during digestion. This study makes the novel first use of an in vitro method to eliminate the inherent complexities and variability of in vivo approaches used to test this hypothesis. Plant miRNA levels in soybean and rice were measured during storage, processing, cooking, and early digestion using real-time PCR. We have demonstrated for the first time that storage, processing, and cooking does not abolish the plant miRNAs present in the foodstuffs. In addition, utilizing a simulated human digestion system revealed significant plant miRNA bioavailability after early stage digestion for 75 min. Attenuation of plant messenger RNA and synthetic miRNA was observed under these conditions. Even after an extensive pretreatment, plant-derived miRNA, delivered by typical dietary ingestion, has a robustness that could make them bioavailable for uptake during early digestion. The potential benefit of these regulatory molecules in pharma nutrition could be explored further. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Aerobic Digestion. Student Manual. Biological Treatment Process Control.

ERIC Educational Resources Information Center

Klopping, Paul H.

This manual contains the textual material for a single-lesson unit on aerobic sludge digestion. Topic areas addressed include: (1) theory of aerobic digestion; (2) system components; (3) performance factors; (4) indicators of stable operation; and (5) operational problems and their solutions. A list of objectives, glossary of key terms, and…

Integrated electrochemical-biological process as an alternative mean for ammonia monitoring during anaerobic digestion of organic wastes.

PubMed

Zhao, Nannan; Li, Xiaohu; Jin, Xiangdan; Angelidaki, Irini; Zhang, Yifeng

2018-03-01

Ammonia monitoring is important to control anaerobic digestion (AD) process due to inhibition effect. Here, an electrolysis cell (EC) was integrated with a complete nitrification reactor as an alternative approach for online monitoring of ammonia during AD processes. The AD effluent was pumped into nitrification reactor to convert ammonia to nitrate, followed by the introduction of nitrate-rich effluent to EC cathode. It was first evaluated with synthetic ammonia-rich digesters and was observed that the current at 5 min were linearly corresponding to the ammonia levels (from 0 to 7.5 mM NH 4 + -N, R 2  = 0.9673). The linear relationship was always observed regardless of different wastewater pH and external voltage. Pre-removal of other electron acceptors from digestate at cathode could eliminate their disturbances to sensor performance. Finally, the accuracy of biosensor was verified with real digestate test. The simple and reliable biosensor showed great promising for online ammonia monitoring of AD processes. Copyright © 2017 Elsevier Ltd. All rights reserved.

Heat damage and in vitro starch digestibility of puffed wheat kernels.

PubMed

Cattaneo, Stefano; Hidalgo, Alyssa; Masotti, Fabio; Stuknytė, Milda; Brandolini, Andrea; De Noni, Ivano

2015-12-01

The effect of processing conditions on heat damage, starch digestibility, release of advanced glycation end products (AGEs) and antioxidant capacity of puffed cereals was studied. The determination of several markers arising from Maillard reaction proved pyrraline (PYR) and hydroxymethylfurfural (HMF) as the most reliable indices of heat load applied during puffing. The considerable heat load was evidenced by the high levels of both PYR (57.6-153.4 mg kg(-1) dry matter) and HMF (13-51.2 mg kg(-1) dry matter). For cost and simplicity, HMF looked like the most appropriate index in puffed cereals. Puffing influenced starch in vitro digestibility, being most of the starch (81-93%) hydrolyzed to maltotriose, maltose and glucose whereas only limited amounts of AGEs were released. The relevant antioxidant capacity revealed by digested puffed kernels can be ascribed to both the new formed Maillard reaction products and the conditions adopted during in vitro digestion. Copyright © 2015 Elsevier Ltd. All rights reserved.

Anaerobic digestion of sulfate-acidified cattle slurry: One-stage vs. two-stage.

PubMed

Moset, Veronica; Ottosen, Lars Ditlev Mørck; Xavier, Cristiane de Almeida Neves; Møller, Henrik Bjarne

2016-05-15

Two strategies to include acidified cattle manure (AcCM) in co-digestion with normal cattle manure (CM) are presented in this work. The strategies are a single thermophilic (50 °C) continuous stirred tank reactor (CSTR) anaerobic digestion and a two-step (65 °C + 50 °C) CSTR process. In both strategies, two different inclusion levels of H2SO4-acidified CM (10% and 20%) in co-digestion with normal CM were tested and compared with a control CSTR fed only CM. Important enhancement of methane (CH4) yield and solid reductions were observed in the thermophilic one-step CSTR working with 10% AcCM. However, a higher inclusion level of AcCM (20%) caused volatile fatty acid accumulation in the reactor and a more than 30% reduction in CH4 production. In terms of CH4 production, when 10% of AcCM was co-digested with 90% of CM, the two-step anaerobic co-digestion yielded less than the single step. During the first step of the two-step CSTR process, acidogenesis and a partial sulfate reduction were achieved. However, sulfide stripping between the first and the second step must be promoted in order to advance this technology. Copyright © 2016 Elsevier Ltd. All rights reserved.

Methane gas generation from waste water extraction process of crude palm oil in experimental digesters

NASA Astrophysics Data System (ADS)

Dillon, A.; Penafiel, R.; Garzón, P. V.; Ochoa, V.

2015-12-01

Industrial processes to extract crude palm oil, generates large amounts of waste water. High concentrations of COD, ST, SV, NH4 + and low solubility of O2, make the treatment of these effluents starts with anaerobic processes. The anaerobic digestion process has several advantages over aerobic degradation: lower operating costs (not aeration), low sludge production, methane gas generation. The 4 stages of anaerobic digestion are: hydrolysis, acidogenic, acetogenesis and methanogenesis. Through the action of enzymes synthesized by microbial consortia are met. The products of each step to serve as reagents is conducted as follows. The organic load times and cell hydraulic retention, solids content, nutrient availability, pH and temperature are factors that influence directly in biodigesters. The objectives of this presentation is to; characterize the microbial inoculum and water (from palm oil wasted water) to be used in biodigestores, make specific methanogenic activity in bioassays, acclimatize the microorganisms to produce methane gas using basal mineral medium with acetate for the input power, and to determine the production of methane gas digesters high organic load.

Effect of processing paddy on digestibility of rice starch by in vitro studies.

PubMed

Chitra, M; Singh, Vasudeva; Ali, S Z

2010-08-01

Paddy (Oryza sativa L) (variety 'IR - 64'), was parboiled, puffed by sand roasting and flaked by edge runner and roller flaker and variations in physical and physicochemical properties were studied. Moisture contents were lower (5.8-10.8%) in processed rice products compared to raw materials (11.8%). Ratio of rice to sand in the case of puffed rice preparation was optimized. The equilibrium moisture content was 27.4% in raw rice while it was much higher (38.9-81.0%) in processed rice. Sedimentation volume was lowest (6.2 ml) in raw rice and highest (18.8 ml) in popped rice. Starch content was 84.8 and 76.5-83% in raw and processed rice, respectively. In vitro starch digestibility was highest in roller flaker flakes and lowest in raw milled rice. Among the ready to eat products, popped rice showed least starch digestibility (∼30%).

A Process for Evaluating Student Records Management Software. ERIC/AE Digest.

ERIC Educational Resources Information Center

Vecchioli, Lisa

This digest provides practical advice on evaluating software for managing student records. An evaluation of record-keeping software should start with a process to identify all of the individual needs the software produce must meet in order to be considered for purchase. The first step toward establishing an administrative computing system is…

Laboratory Exercise: Study of Digestive and Regulatory Processes through the Exploration of Fasted and Postprandial Blood Glucose

ERIC Educational Resources Information Center

Hopper, Mari K.; Maurer, Luke W.

2013-01-01

Digestive physiology laboratory exercises often explore the regulation of enzyme action rather than systems physiology. This laboratory exercise provides a systems approach to digestive and regulatory processes through the exploration of postprandial blood glucose levels. In the present exercise, students enrolled in an undergraduate animal…

Lessons from Digestive-Tract Symbioses Between Bacteria and Invertebrates.

PubMed

Graf, Joerg

2016-09-08

In most animals, digestive tracts harbor the greatest number of bacteria in the animal that contribute to its health: by aiding in the digestion of nutrients, provisioning essential nutrients and protecting against colonization by pathogens. Invertebrates have been used to enhance our understanding of metabolic processes and microbe-host interactions owing to experimental advantages. This review describes how advances in DNA sequencing technologies have dramatically altered how researchers investigate microbe-host interactions, including 16S rRNA gene surveys, metagenome experiments, and metatranscriptome studies. Advantages and challenges of each of these approaches are described herein. Hypotheses generated through omics studies can be directly tested using site-directed mutagenesis, and findings from transposon studies and site-directed experiments are presented. Finally, unique structural aspects of invertebrate digestive tracts that contribute to symbiont specificity are presented. The combination of omics approaches with genetics and microscopy allows researchers to move beyond correlations to identify conserved mechanisms of microbe-host interactions.

Effective removal of the antibiotic Nafcillin from water by combining the Photoelectro-Fenton process and Anaerobic Biological Digestion.

PubMed

Vidal, Jorge; Huiliñir, Cesar; Santander, Rocío; Silva-Agredo, Javier; Torres-Palma, Ricardo A; Salazar, Ricardo

2018-05-15

The elimination of the antibiotic Nafcillin (NAF), which is usually used in hospitals and veterinary clinics around the world, was assessed through a combination of three advanced electrochemical oxidation processes followed by anaerobic digestion process. In the first stage different electrochemical advanced oxidation processes (EAOPs) were used: electro-oxidation with hydrogen peroxide (EO-H 2 O 2 ), electro-Fenton (EF) and Photo electro-Fenton (PEF). After PEF, almost complete and highly efficient degradation and elimination of NAF was achieved, with the concomitant elimination of the associated antimicrobial activity. The fast degradation rate produced by PEF is explained by the oxidative action of hydroxyl radicals (•OH) together with the direct UV photolysis of complexes formed between Fe 3+ and some organic intermediates. Total removal of NAF occurs after 90min of electrolysis by PEF, with the generation of organic intermediates that remain in solution. However, when this post PEF process solution was treated with an anaerobic biological process, the intermediates generated in the electrochemical degradation of NAF were completely eliminated after 24h. The kinetic degradation of NAF as well as the identification/quantification of products and intermediates formed during the degradation of antibiotic, such as inorganic ions, carboxylic acids and aromatic compounds, were determined by chromatographic and photometric methods. Finally, an oxidation pathway is proposed for the complete conversion to CO 2 . Copyright © 2017 Elsevier B.V. All rights reserved.

Long-term thermophilic mono-digestion of rendering wastes and co-digestion with potato pulp.

PubMed

Bayr, S; Ojanperä, M; Kaparaju, P; Rintala, J

2014-10-01

In this study, mono-digestion of rendering wastes and co-digestion of rendering wastes with potato pulp were studied for the first time in continuous stirred tank reactor (CSTR) experiments at 55°C. Rendering wastes have high protein and lipid contents and are considered good substrates for methane production. However, accumulation of digestion intermediate products viz., volatile fatty acids (VFAs), long chain fatty acids (LCFAs) and ammonia nitrogen (NH4-N and/or free NH3) can cause process imbalance during the digestion. Mono-digestion of rendering wastes at an organic loading rate (OLR) of 1.5 kg volatile solids (VS)/m(3)d and hydraulic retention time (HRT) of 50 d was unstable and resulted in methane yields of 450 dm(3)/kg VS(fed). On the other hand, co-digestion of rendering wastes with potato pulp (60% wet weight, WW) at the same OLR and HRT improved the process stability and increased methane yields (500-680 dm(3)/kg VS(fed)). Thus, it can be concluded that co-digestion of rendering wastes with potato pulp could improve the process stability and methane yields from these difficult to treat industrial waste materials. Copyright © 2014 Elsevier Ltd. All rights reserved.

Comparison of the Digestibility of the Major Peanut Allergens in Thermally Processed Peanuts and in Pure Form

PubMed Central

Maleki, Soheila J.; Schmitt, David A.; Galeano, Maria; Hurlburt, Barry K.

2014-01-01

It has been suggested that the boiling or frying of peanuts leads to less allergenic products than roasting. Here, we have compared the digestibility of the major peanut allergens in the context of peanuts subjected to boiling, frying or roasting and in purified form. The soluble peanut extracts and the purified allergens were digested with either trypsin or pepsin and analyzed by gel electrophoresis and western blot. T-cell proliferation was measured for the purified allergens. In most cases, boiled and raw peanut proteins were similarly digestible, but the Ara h 1 protein in the boiled extracts was more resistant to digestion. Most proteins from fried and roasted peanuts were more resistant to digestion than in raw and boiled samples, and more IgE binding fragments survived digestion. High-molecular-weight fragments of Ara h1 were resistant to digestion in fried and roasted samples. Ara h 1 and Ara h 2 purified from roasted peanuts were the most resistant to digestion, but differed in their ability to stimulate T-cells. The differences in digestibility and IgE binding properties of the major allergens in roasted, fried and boiled peanuts may not explain the difference between the prevalence of peanut allergy in different countries that consume peanut following these varied processing methods. PMID:28234320

Suitability of anaerobic digestion effluent as process water for corn fuel ethanol fermentation.

PubMed

Wang, Ke; Zhang, Jian-Hua; Liu, Pei; Mao, Zhong-Gui

2014-01-01

A corn fuel ethanol plant integrated with anaerobic digestion treatment of thin stillage increases the net energy balance. Furthermore, the anaerobic digestion effluent (ADE) can be reused as a potential substitute for process water in the ethanol fermentation. In this study, the suitability of ADE as process water for corn ethanol fermentation was investigated by analyzing the potential inhibitory components in the ADE. It was found that ammonium influenced the growth and metabolism of Saccharomyces cerevisiae. Maximum ethanol production was obtained when the concentration of ammonium nitrogen was 200 mg/L, and ammonium could replace urea as the nitrogen source for S. cerevisiae under this concentration. In the ethanol fermentation with a higher concentration of ammonium, more glycerol was produced, thereby resulting in the decrease of ethanol production. In addition, components except ammonium in the ADE caused no inhibition to ethanol production. These results suggest that ADE could be reused as process water for corn ethanol fermentation without negative effect when ammonium concentration is well controlled.

Influence of Homogenization and Thermal Processing on the Gastrointestinal Fate of Bovine Milk Fat: In Vitro Digestion Study.

PubMed

Liang, Li; Qi, Ce; Wang, Xingguo; Jin, Qingzhe; McClements, David Julian

2017-12-20

Dairy lipids are an important source of energy and nutrients for infants and adults. The dimensions, aggregation state, and interfacial properties of fat globules in raw milk are changed by dairy processing operations, such as homogenization and thermal processing. These changes influence the behavior of fat globules within the human gastrointestinal tract (GIT). The gastrointestinal fate of raw milk, homogenized milk, high temperature short time (HTST) pasteurized milk, and ultrahigh temperature (UHT) pasteurized milk samples was therefore determined using a simulated GIT. The properties of particles in different regions of the GIT depended on the degree of milk processing. Homogenization increased the initial lipid digestion rate but did not influence the final digestion extent. Thermal processing of homogenized milk decreased the initial rate and final extent of lipid digestion, which was attributed to changes in interfacial structure. These results provide insights into the impact of dairy processing on the gastrointestinal fate of milk fat.

Long-term high-solids anaerobic digestion of food waste: Effects of ammonia on process performance and microbial community.

PubMed

Peng, Xuya; Zhang, ShangYi; Li, Lei; Zhao, Xiaofei; Ma, Yao; Shi, Dezhi

2018-04-22

A long-term high solids anaerobic digestion of food waste was conducted to identify microbial mechanisms of ammonia inhibition during digestion and to clarify correlations between ammonia accumulation, microbial community dynamics (diversity, composition, and interactions), and process stability. Results show that the effects of ammonia on process performance and microbial community were indirectly caused by volatile fatty acid accumulation. Excess free ammonia blocked acetate metabolism, leading to process instability. Accumulated acetate caused feedback inhibition at the acetogenesis stage, which resulted in considerable accumulation of propionate, valerate, and other long-chain fatty acids. This high concentration of volatile fatty acids reduced the abundance of syntrophic acetogenic bacteria and allowed hydrolytic fermentative bacteria to dominate. The normally interactive and orderly metabolic network was broken, which further exacerbated the process instability. These results improve the understanding of microbial mechanisms which contribute to process instability and provide guidance for the microbial management of anaerobic digesters. Copyright © 2018 Elsevier Ltd. All rights reserved.

Digestibility of Bovine Serum Albumin and Peptidomics of the Digests: Effect of Glycation Derived from α-Dicarbonyl Compounds.

PubMed

Sheng, Bulei; Larsen, Lotte Bach; Le, Thao T; Zhao, Di

2018-03-21

α-Dicarbonyl compounds, which are widely generated during sugar fragmentation and oil oxidation, are important precursors of advanced glycation end products (AGEs). In this study, the effect of glycation derived from glyoxal (GO), methylglyoxal (MGO) and diacetyl (DA) on the in vitro digestibility of bovine serum albumin (BSA) was investigated. Glycation from α-dicarbonyl compounds reduced digestibility of BSA in both gastric and intestinal stage of digestion according to measurement of degree of hydrolysis. Changes in peptide composition of digests induced by glycation were displayed, showing absence of peptides, occurrence of new peptides and formation of peptide-AGEs, based on the results obtained using liquid chromatography electron-spray-ionization tandem mass spectrometry (LC-ESI-MS/MS). Crosslinked glycation structures derived from DA largely reduced the sensitivity of glycated BSA towards digestive proteases based on sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) results. Network structures were found to remain in the digests of glycated samples by transmission electron microscope (TEM), thus the impact of AGEs in unabsorbed digests on the gut flora should be an interest for further studies.

Composting of the solid fraction of digestate derived from pig slurry: Biological processes and compost properties

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tambone, Fulvia, E-mail: fulvia.tambone@unimi.it; Terruzzi, Laura; Scaglia, Barbara

Highlights: • Anaerobic digestion leads to the production of a biologically stable digestate. • Solid–liquid separation produces a solid fraction having high fertilizer value. • Composting process shows low biological activity due to high biological stability of digestate. • Solid digestate fraction can be composted in a short time or used directly as organic fertilizer. - Abstract: The aim of this paper was to assess the characteristics of the solid fractions (SF) obtained by mechanical separation of digestate, their compostability and compost quality. To do so, the SF of digestates obtained from anaerobic digestion of pig slurry, energy crops andmore » agro-industrial residues were sampled in five plants located in Northern Italy. Results obtained indicated that anaerobic digestion by itself promoted the high biological stability of biomasses with a Potential Dynamic Respiration Index (PDRI) close to 1000 mgO{sub 2} kg V S{sup −1} h{sup −1}. Subsequent composting of digestates, with an added bulking agent, did not give remarkably different results, and led only to a slight modification of the characteristics of the initial non-composted mixtures; the composts obtained fully respected the legal limits for high quality compost. Chemical studies of organic matter composition of the biomasses by using CP MAS {sup 13}C NMR, indicated that the compost was composed of a high relative content of O-alkyl-C (71.47% of total C) (cellulose and hemicelluloses) and a low alkyl-C (12.42%) (i.e. volatile fatty acids, steroid-like molecules, aliphatic biopolymers and proteins)« less

Digestive Enzyme Supplementation in Gastrointestinal Diseases.

PubMed

Ianiro, Gianluca; Pecere, Silvia; Giorgio, Valentina; Gasbarrini, Antonio; Cammarota, Giovanni

2016-01-01

Digestive enzymes are able to break down proteins and carbohydrates and lipids, and their supplementation may play a role in the management of digestive disorders, from lactose intolerance to cystic fibrosis. To date, several formulations of digestive enzymes are available on the market, being different each other in terms of enzyme type, source and origin, and dosage. This review, performed through a non-systematic search of the available literature, will provide an overview of the current knowledge of digestive enzyme supplementation in gastrointestinal disorders, discussion of the use of pancreatic enzymes, lactase (β-galactosidase) and conjugated bile acids, and also exploring the future perspective of digestive enzyme supplementation. Currently, the animal-derived enzymes represent an established standard of care, however the growing study of plant-based and microbe-derived enzymes offers great promise in the advancement of digestive enzyme therapy. New frontiers of enzyme replacement are being evaluated also in the treatment of diseases not specifically related to enzyme deficiency, whereas the combination of different enzymes might constitute an intriguing therapeutic option in the future.

Bi-compartmental elderly or adult dynamic digestion models applied to interrogate protein digestibility.

PubMed

Levi, Carmit Shani; Lesmes, Uri

2014-10-01

The world's population is inevitably ageing thanks to modern progress; however, the development of food and oral formulations tailored to the needs of the elderly is still in its infancy. In vitro digestion models offer high throughput, robust and practically ethics free evaluation of the digestive fate of ingested products. To date, no data have been made publicly available to facilitate the development or application of an in vitro model mirroring the physicochemical conditions of the elderly gastrointestinal system. This study reports the development of a novel and highly bio-relevant in vitro model based on two serially connected bioreactors recreating the dynamic conditions of the adult or elderly alimentary canal. This report and its supplementary material describe in detail the set-up of the system, the applied physicochemical parameters and the development of the controlling software. These are intended to openly depict a versatile platform, which could assist future efforts to develop age-tailored oral formulations. SDS-PAGE analyses of samples collected from the in vitro digestion of β-lactoglobulin, α-lactalbumin and lactoferrin suggest the bioaccessibility of "slow digesting" and "fast digesting" proteins identified in adult models do not necessarily maintain this trait under elderly gastro-intestinal conditions. Overall, this study brings forward a new generic yet advanced model that could facilitate age-tailoring the digestive fate of liquid formulations.

Recovery of ammonia in digestates of calf manure through a struvite precipitation process using unconventional reagents.

PubMed

Siciliano, A; De Rosa, S

2014-01-01

Land spreading of digestates causes the discharge of large quantities of nutrients into the environment, which contributes to eutrophication and depletion of dissolved oxygen in water bodies. For the removal of ammonia nitrogen, there is increasing interest in the chemical precipitation of struvite, which is a mineral that can be reused as a slow-release fertilizer. However, this process is an expensive treatment of digestate because large amounts of magnesium and phosphorus reagents are required. In this paper, a struvite precipitation-based process is proposed for an efficient recovery of digestate nutrients using low-cost reagents. In particular, seawater bittern, a by-product of marine salt manufacturing and bone meal, a by-product of the thermal treatment of meat waste, have been used as low-cost sources of magnesium and phosphorus, respectively. Once the operating conditions are defined, the process enables the removal of more than 90% ammonia load, the almost complete recovery of magnesium and phosphorus and the production of a potentially valuable precipitate containing struvite crystals.

Methane-yielding microbial communities processing lactate-rich substrates: a piece of the anaerobic digestion puzzle.

PubMed

Detman, Anna; Mielecki, Damian; Pleśniak, Łukasz; Bucha, Michał; Janiga, Marek; Matyasik, Irena; Chojnacka, Aleksandra; Jędrysek, Mariusz-Orion; Błaszczyk, Mieczysław K; Sikora, Anna

2018-01-01

Anaerobic digestion, whose final products are methane and carbon dioxide, ensures energy flow and circulation of matter in ecosystems. This naturally occurring process is used for the production of renewable energy from biomass. Lactate, a common product of acidic fermentation, is a key intermediate in anaerobic digestion of biomass in the environment and biogas plants. Effective utilization of lactate has been observed in many experimental approaches used to study anaerobic digestion. Interestingly, anaerobic lactate oxidation and lactate oxidizers as a physiological group in methane-yielding microbial communities have not received enough attention in the context of the acetogenic step of anaerobic digestion. This study focuses on metabolic transformation of lactate during the acetogenic and methanogenic steps of anaerobic digestion in methane-yielding bioreactors. Methane-yielding microbial communities instead of pure cultures of acetate producers were used to process artificial lactate-rich media to methane and carbon dioxide in up-flow anaerobic sludge blanket reactors. The media imitated the mixture of acidic products found in anaerobic environments/digesters where lactate fermentation dominates in acidogenesis. Effective utilization of lactate and biogas production was observed. 16S rRNA profiling was used to examine the selected methane-yielding communities. Among Archaea present in the bioreactors, the order Methanosarcinales predominated. The acetoclastic pathway of methane formation was further confirmed by analysis of the stable carbon isotope composition of methane and carbon dioxide. The domain Bacteria was represented by Bacteroidetes , Firmicutes , Proteobacteria , Synergistetes , Actinobacteria , Spirochaetes , Tenericutes , Caldithrix , Verrucomicrobia , Thermotogae , Chloroflexi , Nitrospirae, and Cyanobacteria. Available genome sequences of species and/or genera identified in the microbial communities were searched for genes encoding the lactate

The challenges of anaerobic digestion and the role of biochar in optimizing anaerobic digestion.

PubMed

Fagbohungbe, Michael O; Herbert, Ben M J; Hurst, Lois; Ibeto, Cynthia N; Li, Hong; Usmani, Shams Q; Semple, Kirk T

2017-03-01

Biochar, like most other adsorbents, is a carbonaceous material, which is formed from the combustion of plant materials, in low-zero oxygen conditions and results in a material, which has the capacity to sorb chemicals onto its surfaces. Currently, research is being carried out to investigate the relevance of biochar in improving the soil ecosystem, digestate quality and most recently the anaerobic digestion process. Anaerobic digestion (AD) of organic substrates provides both a sustainable source of energy and a digestate with the potential to enhance plant growth and soil health. In order to ensure that these benefits are realised, the anaerobic digestion system must be optimized for process stability and high nutrient retention capacity in the digestate produced. Substrate-induced inhibition is a major issue, which can disrupt the stable functioning of the AD system reducing microbial breakdown of the organic waste and formation of methane, which in turn reduces energy output. Likewise, the spreading of digestate on land can often result in nutrient loss, surface runoff and leaching. This review will examine substrate inhibition and their impact on anaerobic digestion, nutrient leaching and their environmental implications, the properties and functionality of biochar material in counteracting these challenges. Copyright © 2016 Elsevier Ltd. All rights reserved.

Digestion proteomics: tracking lactoferrin truncation and peptide release during simulated gastric digestion.

PubMed

Grosvenor, Anita J; Haigh, Brendan J; Dyer, Jolon M

2014-11-01

The extent to which nutritional and functional benefit is derived from proteins in food is related to its breakdown and digestion in the body after consumption. Further, detailed information about food protein truncation during digestion is critical to understanding and optimising the availability of bioactives, in controlling and limiting allergen release, and in minimising or monitoring the effects of processing and food preparation. However, tracking the complex array of products formed during the digestion of proteins is not easily accomplished using classical proteomics. We here present and develop a novel proteomic approach using isobaric labelling to mapping and tracking protein truncation and peptide release during simulated gastric digestion, using bovine lactoferrin as a model food protein. The relative abundance of related peptides was tracked throughout a digestion time course, and the effect of pasteurisation on peptide release assessed. The new approach to food digestion proteomics developed here therefore appears to be highly suitable not only for tracking the truncation and relative abundance of released peptides during gastric digestion, but also for determining the effects of protein modification on digestibility and potential bioavailability.

Modelling of the production of gaseous by-products in anaerobic digestion.

PubMed

Strik, D P; Domnanovich, A M; Pfeiffer, B; Karlovitz, M; Zani, L; Braun, R; Holubar, P

2003-01-01

Goal of the EU-Project AMONCO (Advanced Prediction, Monitoring and Controlling of Anaerobic Digestion Processes Behaviour towards Biogas Usage in Fuel Cells) is demonstration of the practical use of biogas in fuel cells. The right precondition is a biogas quality which fits into the fuel cells tolerances. Therefore the mission of the workgroup Environmental biotechnology is to control anaerobic digestion in a way that production of potential harmful by-products for fuel cells is reduced. A good understanding of the production of these by products is essential for an applicable decision support tool. This poster presents the modelling of hydrogen sulfide by means of hierarchical neural networks and a classical mathematical method.

Novel process combining anaerobic-aerobic digestion and ion exchange resin for full recycling of cassava stillage in ethanol fermentation.

PubMed

Yang, Xinchao; Wang, Ke; Wang, Huijun; Zhang, Jianhua; Mao, Zhonggui

2017-04-01

A novel cleaner ethanol production process has been developed. Thin stillage is treated initially by anaerobic digestion followed by aerobic digestion and then further treated by chloride anion exchange resin. This allows the fully-digested and resin-treated stillage to be completely recycled for use as process water in the next ethanol fermentation batch, which eliminates wastewater discharges and minimizes consumption of fresh water. The method was evaluated at the laboratory scale. Process parameters were very similar to those found using tap water. Maximal ethanol production rate in the fully-recycled stillage was 0.9g/L/h, which was similar to the 0.9g/L/h found with the tap water control. The consumption of fresh water was reduced from 4.1L/L (fresh water/ethanol) to zero. Compared with anaerobically-aerobically digested stillage which had not been treated with resin, the fermentation time was reduced by 28% (from 72h to 52h) and reached the level achieved with tap water. This novel process can assist in sustainable development of the ethanol industry. Copyright © 2017 Elsevier Ltd. All rights reserved.

Comparison of sidestream treatment technologies: post aerobic digestion and Anammox.

PubMed

Bauer, Heidi; Johnson, Thomas D; Johnson, Bruce R; Oerke, David; Graziano, Steven

2016-01-01

Post aerobic digestion (PAD) and anaerobic ammonium oxidation (Anammox) are sidestream treatment technologies which are both excellent options for the reduction of nitrogen recycled back to the liquid stream without the need for supplemental carbon or alkalinity. However, the achievement of this goal is where the similarities between the two technologies end. PAD is an advanced digestion process where aerobic digestion is designed to follow anaerobic digestion. Other benefits of PAD include volatile solids reduction, odor reduction, and struvite formation reduction. Anammox harnesses a specific species of autotrophic bacteria that can help achieve partial nitritation/deammonification. Other benefits of Anammox include lower energy consumption due to requiring less oxygen compared with conventional nitrification. This manuscript describes the unique benefits and challenges of each technology. Example installations are presented with a narrative of how and why the technology was selected. A whole plant simulator is used to compare and contrast the mass balances and net present value costs on an 'apples to apples' basis. The discussion includes descriptions of conditions under which each technology would potentially be the most beneficial and cost-effective against a baseline facility without sidestream treatment.

Effect of drying process assisted by high-pressure impregnation on protein quality and digestibility in red abalone (Haliotis rufescens).

PubMed

Cepero-Betancourt, Yamira; Oliva-Moresco, Patricio; Pasten-Contreras, Alexis; Tabilo-Munizaga, Gipsy; Pérez-Won, Mario; Moreno-Osorio, Luis; Lemus-Mondaca, Roberto

2017-10-01

Abalone (Haliotis spp.) is an exotic seafood product recognized as a protein source of high biological value. Traditional methods used to preserve foods such as drying technology can affect their nutritional quality (protein quality and digestibility). A 28-day rat feeding study was conducted to evaluate the effects of the drying process assisted by high-pressure impregnation (HPI) (350, 450, and 500 MPa × 5 min) on chemical proximate and amino acid compositions and nutritional parameters, such as protein efficiency ratio (PER), true digestibility (TD), net protein ratio, and protein digestibility corrected amino acid score (PDCAAS) of dried abalone. The HPI-assisted drying process ensured excellent protein quality based on PER values, regardless of the pressure level. At 350 and 500 MPa, the HPI-assisted drying process had no negative effect on TD and PDCAAS then, based on nutritional parameters analysed, we recommend HPI-assisted drying process at 350 MPa × 5 min as the best process condition to dry abalone. Variations in nutritional parameters compared to casein protein were observed; nevertheless, the high protein quality and digestibility of HPI-assisted dried abalones were maintained to satisfy the metabolic demands of human beings.

Optimization of solid state anaerobic digestion of the OFMSW by digestate recirculation: A new approach

DOE Office of Scientific and Technical Information (OSTI.GOV)

Michele, Pognani, E-mail: michele.pognani@unimi.it; Giuliana, D’Imporzano, E-mail: giuliana.dimporzano@unimi.it; Gruppo Ricicla - DiSAA, Università degli Studi di Milano, Biomass and Bioenergy Lab., Parco Tecnologico Padano, Via Einstein, Loc. C.na Codazza, 26900 Lodi

2015-01-15

Highlights: • Solid State Anaerobic Digestion (SSAD) of OFMSW can be optimized by irrigation with digestate. • Digestate spreading allows keeping optimal process parameters and high hydrolysis rate. • The 18.4% of CH{sub 4} was produced in the reactor, leaving the 49.7% in the percolate. • Successive CSTR feed with percolate shows a biogas enriched in methane (more than 80%). • The proposed process allow producing the 68% of OFMSW potential CH{sub 4}, getting high quality organic amendment. - Abstract: Dry anaerobic digestion (AD) of OFMSW was optimized in order to produce biogas avoiding the use of solid inoculum. Doingmore » so the dry AD was performed irrigating the solid waste with liquid digestate (flow rate of 1:1.18–1:0.9 w/w waste/digestate; 21 d of hydraulic retention time – HRT) in order to remove fermentation products inhibiting AD process. Results indicated that a high hydrolysis rate of organic matter (OM) and partial biogas production were obtained directly during the dry AD. Hydrolysate OM was removed from digester by the percolate flow and it was subsequently used to feed a liquid anaerobic digester. During dry AD a total loss of 36.9% of total solids was recorded. Methane balance indicated that 18.4% of potential methane can be produced during dry AD and 49.7% by the percolate. Nevertheless results obtained for liquid AD digestion indicated that only 20.4% and 25.7% of potential producible methane was generated by adopting 15 and 20 days of HRT, probably due to the AD inhibition due to high presence of toxic ammonia forms in the liquid medium.« less

Advancing Your Library's Web-Based Services. ERIC Digest.

ERIC Educational Resources Information Center

Feldman, Sari; Strobel, Tracy

This digest discusses the development of World Wide Web-based services for libraries and provides examples from the Cleveland Public Library (CPL). The first section highlights the importance of developing such services, steps to be followed for a successful project, and the importance of having the goal of replicating and enhancing traditional…

Sludge stabilization through aerobic digestion

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hartman, R.B.; Smith, D.G.; Bennett, E.R.

1979-10-01

The aerobic digestion process with certain modifications is evaluated as an alternative for sludge processing capable of developing a product with characteristics required for land application. Environmental conditions, including temperature, solids concentration, and digestion time, that affect the aerobic digestion of a mixed primary sludge-trickling filter humus are investigated. Variations in these parameters that influence the characteristics of digested sludge are determined, and the parameters are optimized to: provide the maximum rate of volatile solids reduction; develop a stable, nonodorous product sludge; and provide the maximum rate of oxidation of the nitrogenous material present in the feed sludge. (3 diagrams,more » 9 graphs, 15 references, 3 tables)« less

Relating Anaerobic Digestion Microbial Community and Process Function.

PubMed

Venkiteshwaran, Kaushik; Bocher, Benjamin; Maki, James; Zitomer, Daniel

2015-01-01

Anaerobic digestion (AD) involves a consortium of microorganisms that convert substrates into biogas containing methane for renewable energy. The technology has suffered from the perception of being periodically unstable due to limited understanding of the relationship between microbial community structure and function. The emphasis of this review is to describe microbial communities in digesters and quantitative and qualitative relationships between community structure and digester function. Progress has been made in the past few decades to identify key microorganisms influencing AD. Yet, more work is required to realize robust, quantitative relationships between microbial community structure and functions such as methane production rate and resilience after perturbations. Other promising areas of research for improved AD may include methods to increase/control (1) hydrolysis rate, (2) direct interspecies electron transfer to methanogens, (3) community structure-function relationships of methanogens, (4) methanogenesis via acetate oxidation, and (5) bioaugmentation to study community-activity relationships or improve engineered bioprocesses.

Effect of process temperature, pH and suspended solids content upon pasteurization of a model agricultural waste during thermophilic aerobic digestion.

PubMed

Ugwuanyi, J O; Harvey, L M; McNeil, B

1999-09-01

Thermophilic aerobic digestion(TAD), or liquid composting, is a versatile new process for the treatment and stabilization of high strength wastes of liquid or, perhaps more importantly, slurry consistency. The pattern of inactivation of various pathogenic and indicator organisms was studied using batch digestions under conditions that may be expected to be found in full-scale TAD processes. Rapid inactivation of test populations occurred within the first 10 min from the start of digestion. The inactivation rate was slightly lower when digestions were conducted below 60 degrees C. In some instances, a 'tail' was apparent, possibly indicating the survival of relatively resistant sub-populations particularly in the case of Serratia marcescens and Enterococcus faecalis, or of clumping or attachment of cells to particulate materials. The effect of pH on the inactivation of the test populations depended on the temperature of digestion, but varied with the test population. At 55 degrees C Escherichia coli was more sensitive to temperature effects at pH 7 than at pH 8, but was more sensitive at pH 8, 60 degrees C. The reverse was the case at 60 degrees C for Ent. faecalis. An increase in the solid content of the digesting waste caused a progressive increase in the protection of test organisms from thermal inactivation. Challenging a TAD process with test strains allows (via estimation of D-values) a quantification of the cidal effects of such processes, with a view to manipulating process variables to enhance such effects.

Proteolytic Digestion and TiO2 Phosphopeptide Enrichment Microreactor for Fast MS Identification of Proteins

NASA Astrophysics Data System (ADS)

Deng, Jingren; Lazar, Iulia M.

2016-04-01

The characterization of phosphorylation state(s) of a protein is best accomplished by using isolated or enriched phosphoprotein samples or their corresponding phosphopeptides. The process is typically time-consuming as, often, a combination of analytical approaches must be used. To facilitate throughput in the study of phosphoproteins, a microreactor that enables a novel strategy for performing fast proteolytic digestion and selective phosphopeptide enrichment was developed. The microreactor was fabricated using 100 μm i.d. fused-silica capillaries packed with 1-2 mm beds of C18 and/or TiO2 particles. Proteolytic digestion-only, phosphopeptide enrichment-only, and sequential proteolytic digestion/phosphopeptide enrichment microreactors were developed and tested with standard protein mixtures. The protein samples were adsorbed on the C18 particles, quickly digested with a proteolytic enzyme infused over the adsorbed proteins, and further eluted onto the TiO2 microreactor for enrichment in phosphopeptides. A number of parameters were optimized to speed up the digestion and enrichments processes, including microreactor dimensions, sample concentrations, digestion time, flow rates, buffer compositions, and pH. The effective time for the steps of proteolytic digestion and enrichment was less than 5 min. For simple samples, such as standard protein mixtures, this approach provided equivalent or better results than conventional bench-top methods, in terms of both enzymatic digestion and selectivity. Analysis times and reagent costs were reduced ~10- to 15-fold. Preliminary analysis of cell extracts and recombinant proteins indicated the feasibility of integration of these microreactors in more advanced workflows amenable for handling real-world biological samples.

Evaluation of the rotary drum reactor process as pretreatment technology of municipal solid waste for thermophilic anaerobic digestion and biogas production.

PubMed

Gikas, Petros; Zhu, Baoning; Batistatos, Nicolas Ion; Zhang, Ruihong

2018-06-15

Municipal solid waste (MSW) contains a large fraction of biodegradable organic materials. When disposed in landfills, these materials can cause adverse environmental impact due to gaseous emissions and leachate generation. This study was performed with an aim of effectively separating the biodegradable materials from a Mechanical Biological Treatment (MBT) facility and treating them in well-controlled anaerobic digesters for biogas production. The rotary drum reactor (RDR) process (a sub-process of the MBT facilities studied in the present work) was evaluated as an MSW pretreatment technology for separating and preparing the biodegradable materials in MSW to be used as feedstock for anaerobic digestion. The RDR processes used in six commercial MSW treatment plants located in the USA were surveyed and sampled. The samples of the biodegradable materials produced by the RDR process were analyzed for chemical and physical characteristics as well as anaerobically digested in the laboratory using batch reactors under thermophilic conditions. The moisture content, TS, VS and C/N of the samples varied between 64.7 and 44.4%, 55.6 to 35.3%, 27.0 to 41.3% and 24.5 to 42.7, respectively. The biogas yield was measured to be between 533.0 and 675.6 mL g -1 VS after 20 days of digestion. Approximately 90% of the biogas was produced during the first 13 days. The average methane content of the biogas was between 58.0 and 59.9%. The results indicated that the biodegradable materials separated from MSW using the RDR processes could be used as an excellent feedstock for anaerobic digestion. The digester residues may be further processed for compost production or further energy recovery by using thermal conversion processes such as combustion or gasification. Copyright © 2017. Published by Elsevier Ltd.

The role of anaerobic digestion in the emerging energy economy.

PubMed

Batstone, Damien John; Virdis, Bernardino

2014-06-01

Anaerobic digestion is the default process for biological conversion of residue organics to renewable energy and biofuel in the form of methane. However, its scope of application is expanding, due to availability of new technologies, and the emerging drivers of energy and nutrient conservation and recovery. Here, we outline two of these new application areas, namely wastewater nutrient and energy recovery, and generation of value added chemicals through mixed culture biotechnology. There exist two options for nutrient and energy recovery from domestic wastewater: low energy mainline and partition-release-recovery. Both are heavily dependent on anaerobic digestion as an energy generating and nutrient release step, and have been enabled by new technologies such as low emission anaerobic membrane processes. The area of mixed culture biotechnology has been previously identified as a key industrial opportunity, but is now moving closer to application due application of existing and new technologies. As well as acting as a core technology option in bioproduction, anaerobic digestion has a key role in residual waste valorization and generation of energy for downstream processing. These new application areas and technologies are emerging simultaneously with substantial advances in knowledge of underlying mechanisms such as electron transfer, understanding of which is critical to development of the new application areas. Copyright © 2014 Elsevier Ltd. All rights reserved.

Two-stage anaerobic and post-aerobic mesophilic digestion of sewage sludge: Analysis of process performance and hygienization potential.

PubMed

Tomei, M Concetta; Mosca Angelucci, Domenica; Levantesi, Caterina

2016-03-01

Sequential anaerobic-aerobic digestion has been demonstrated to be effective for enhanced sludge stabilization, in terms of increased solid reduction and improvement of sludge dewaterability. In this study, we propose a modified version of the sequential anaerobic-aerobic digestion process by operating the aerobic step under mesophilic conditions (T=37 °C), in order to improve the aerobic degradation kinetics of soluble and particulate chemical oxygen demand (COD). Process performance has been assessed in terms of "classical parameters" such as volatile solids (VS) removal, biogas production, COD removal, nitrogen species, and polysaccharide and protein fate. The aerobic step was operated under intermittent aeration to achieve nitrogen removal. Aerobic mesophilic conditions consistently increased VS removal, providing 32% additional removal vs. 20% at 20 °C. Similar results were obtained for nitrogen removal, increasing from 64% up to 99% at the higher temperature. Improved sludge dewaterability was also observed with a capillary suction time decrease of ~50% during the mesophilic aerobic step. This finding may be attributable to the decreased protein content in the aerobic digested sludge. The post-aerobic digestion exerted a positive effect on the reduction of microbial indicators while no consistent improvement of hygienization related to the increased temperature was observed. The techno-economic analysis of the proposed digestion layout showed a net cost saving for sludge disposal estimated in the range of 28-35% in comparison to the single-phase anaerobic digestion. Copyright © 2015 Elsevier B.V. All rights reserved.

Photoenhanced anaerobic digestion of organic acids

DOEpatents

Weaver, Paul F.

1990-01-01

A process is described for rapid conversion of organic acids and alcohols anaerobic digesters into hydrogen and carbon dioxide, the optimal precursor substrates for production of methane. The process includes addition of photosynthetic bacteria to the digester and exposure of the bacteria to radiant energy (e.g., solar energy). The process also increases the pH stability of the digester to prevent failure of the digester. Preferred substrates for photosynthetic bacteria are the organic acid and alcohol waste products of fermentative bacteria. In mixed culture with methanogenic bacteria or in defined co-culture with non-aceticlastic methanogenic bacteria, photosynthetic bacteria are capable of facilitating the conversion or organic acids and alcohols into methane with low levels of light energy input.

Advanced process control framework initiative

NASA Astrophysics Data System (ADS)

Hill, Tom; Nettles, Steve

1997-01-01

The semiconductor industry, one the world's most fiercely competitive industries, is driven by increasingly complex process technologies and global competition to improve cycle time, quality, and process flexibility. Due to the complexity of these problems, current process control techniques are generally nonautomated, time-consuming, reactive, nonadaptive, and focused on individual fabrication tools and processes. As the semiconductor industry moves into higher density processes, radical new approaches are required. To address the need for advanced factory-level process control in this environment, Honeywell, Advanced Micro Devices (AMD), and SEMATECH formed the Advanced Process Control Framework Initiative (APCFI) joint research project. The project defines and demonstrates an Advanced Process Control (APC) approach based on SEMATECH's Computer Integrated Manufacturing (CIM) Framework. Its scope includes the coordination of Manufacturing Execution Systems, process control tools, and wafer fabrication equipment to provide necessary process control capabilities. Moreover, it takes advantage of the CIM Framework to integrate and coordinate applications from other suppliers that provide services necessary for the overall system to function. This presentation discusses the key concept of model-based process control that differentiates the APC Framework. This major improvement over current methods enables new systematic process control by linking the knowledge of key process settings to desired product characteristics that reside in models created with commercial model development tools The unique framework-based approach facilitates integration of commercial tools and reuse of their data by tying them together in an object-based structure. The presentation also explores the perspective of each organization's involvement in the APCFI project. Each has complementary goals and expertise to contribute; Honeywell represents the supplier viewpoint, AMD represents the user

VERIFICATION OF THE DEFENSE WASTE PROCESSING FACILITY PROCESS DIGESTION METHOD FOR THE SLUDGE BATCH 6 QUALIFICATION SAMPLE

DOE Office of Scientific and Technical Information (OSTI.GOV)

Click, D.; Jones, M.; Edwards, T.

2010-06-09

For each sludge batch that is processed in the Defense Waste Processing Facility (DWPF), the Savannah River National Laboratory (SRNL) confirms applicability of the digestion method to be used by the DWPF lab for elemental analysis of Sludge Receipt and Adjustment Tank (SRAT) receipt samples and SRAT product process control samples.1 DWPF SRAT samples are typically dissolved using a room temperature HF-HNO3 acid dissolution (i.e., DWPF Cold Chem (CC) Method, see DWPF Procedure SW4-15.201) and then analyzed by inductively coupled plasma - atomic emission spectroscopy (ICPAES). In addition to the CC method confirmation, the DWPF lab's mercury (Hg) digestion methodmore » was also evaluated for applicability to SB6 (see DWPF procedure 'Mercury System Operating Manual', Manual: SW4-15.204. Section 6.1, Revision 5, Effective date: 12-04-03). This report contains the results and comparison of data generated from performing the Aqua Regia (AR), Sodium Peroxide/Hydroxide Fusion (PF) and DWPF Cold Chem (CC) method digestion of Sludge Batch 6 (SB6) SRAT Receipt and SB6 SRAT Product samples. For validation of the DWPF lab's Hg method, only SRAT receipt material was used and compared to AR digestion results. The SB6 SRAT Receipt and SB6 SRAT Product samples were prepared in the SRNL Shielded Cells, and the SRAT Receipt material is representative of the sludge that constitutes the SB6 Batch or qualification composition. This is the sludge in Tank 51 that is to be transferred into Tank 40, which will contain the heel of Sludge Batch 5 (SB5), to form the SB6 Blend composition. In addition to the 16 elements currently measured by the DWPF, this report includes Hg and thorium (Th) data (Th comprising {approx}2.5 - 3 Wt% of the total solids in SRAT Receipt and SRAT Product, respectively) and provides specific details of ICP-AES analysis of Th. Thorium was found to interfere with the U 367.007 nm emission line, and an inter-element correction (IEC) had to be applied to U data, which

Process for producing advanced ceramics

DOEpatents

Kwong, Kyei-Sing

1996-01-01

A process for the synthesis of homogeneous advanced ceramics such as SiC+AlN, SiAlON, SiC+Al.sub.2 O.sub.3, and Si.sub.3 N.sub.4 +AlN from natural clays such as kaolin, halloysite and montmorillonite by an intercalation and heat treatment method. Included are the steps of refining clays, intercalating organic compounds into the layered structure of clays, drying the intercalated mixture, firing the treated atmospheres and grinding the loosely agglomerated structure. Advanced ceramics produced by this procedure have the advantages of homogeneity, cost effectiveness, simplicity of manufacture, ease of grind and a short process time. Advanced ceramics produced by this process can be used for refractory, wear part and structure ceramics.

Growth media in anaerobic fermentative processes: The underestimated potential of thermophilic fermentation and anaerobic digestion.

PubMed

Hendriks, A T W M; van Lier, J B; de Kreuk, M K

Fermentation and anaerobic digestion of organic waste and wastewater is broadly studied and applied. Despite widely available results and data for these processes, comparison of the generated results in literature is difficult. Not only due to the used variety of process conditions, but also because of the many different growth media that are used. Composition of growth media can influence biogas production (rates) and lead to process instability during anaerobic digestion. To be able to compare results of the different studies reported, and to ensure nutrient limitation is not influencing observations ascribed to process dynamics and/or reaction kinetics, a standard protocol for creating a defined growth medium for anaerobic digestion and mixed culture fermentation is proposed. This paper explains the role(s) of the different macro- and micronutrients, as well as the choices for a growth medium formulation strategy. In addition, the differences in nutrient requirements between mesophilic and thermophilic systems are discussed as well as the importance of specific trace metals regarding specific conversion routes and the possible supplementary requirement of vitamins. The paper will also give some insight into the bio-availability and toxicity of trace metals. A remarkable finding is that mesophilic and thermophilic enzymes are quite comparable at their optimum temperatures. This has consequences for the trace metal requirements of thermophiles under certain conditions. Under non-limiting conditions, the trace metal requirement of thermophilic systems is about 3 times higher than for mesophilic systems. Copyright © 2017 Elsevier Inc. All rights reserved.

Digestive oncologist in the gastroenterology training curriculum

PubMed Central

Mulder, Chris Jacob Johan; Peeters, Marc; Cats, Annemieke; Dahele, Anna; Droste, Jochim Terhaar sive

2011-01-01

Until the late 1980s, gastroenterology (GE) was considered a subspecialty of Internal Medicine. Today, GE also incorporates Hepatology. However, Digestive Oncology training is poorly defined in the Hepatogastroenterology (HGE)-curriculum. Therefore, a Digestive Oncology curriculum should be developed and this document might be a starting point for such a curriculum. HGE-specialists are increasingly resisting the paradigm in which they play only a diagnostic and technical role in the management of digestive tumors. We suggest minimum end-points in the standard HGE-curriculum for oncology, and recommend a focus year in the Netherlands for Digestive Oncology in the HGE-curriculum. To produce well-trained digestive oncologists, an advanced Digestive Oncology training program with specific qualifications in Digestive Oncology (2 years) has been developed. The schedule in Belgium includes a period of at least 6 mo to be spent in a medical oncology department. The goal of these programs remains the production of well-trained digestive oncologists. HGE specialists are part of the multidisciplinary oncological teams, and some have been administering chemotherapy in their countries for years. In this article, we provide a road map for the organization of a proper training in Digestive Oncology. We hope that the World Gastroenterology Organisation and other (inter)national societies will support the necessary certifications for this specific training in the HGE-curriculum. PMID:21556128

The food matrix affects the anthocyanin profile of fortified egg and dairy matrices during processing and in vitro digestion.

PubMed

Pineda-Vadillo, Carlos; Nau, Françoise; Guerin-Dubiard, Catherin; Jardin, Julien; Lechevalier, Valérie; Sanz-Buenhombre, Marisa; Guadarrama, Alberto; Tóth, Tamás; Csavajda, Éva; Hingyi, Hajnalka; Karakaya, Sibel; Sibakov, Juhani; Capozzi, Francesco; Bordoni, Alessandra; Dupont, Didier

2017-01-01

The aim of the present study was to understand to what extent the inclusion of anthocyanins into dairy and egg matrices could affect their stability after processing and their release and solubility during digestion. For this purpose, individual and total anthocyanin content of four different enriched matrices, namely custard dessert, milkshake, pancake and omelettete, was determined after their manufacturing and during in vitro digestion. Results showed that anthocyanin recovery after processing largely varied among matrices, mainly due to the treatments applied and the interactions developed with other food components. In terms of digestion, the present study showed that the inclusion of anthocyanins into food matrices could be an effective way to protect them against intestinal degradation, and also the incorporation of anthocyanins into matrices with different compositions and structures could represent an interesting and effective method to control the delivery of anthocyanins within the different compartments of the digestive tract. Copyright © 2016 Elsevier Ltd. All rights reserved.

Microbial community structure in a thermophilic aerobic digester used as a sludge pretreatment process for the mesophilic anaerobic digestion and the enhancement of methane production.

PubMed

Jang, Hyun Min; Park, Sang Kyu; Ha, Jeong Hyub; Park, Jong Moon

2013-10-01

An effective two-stage sewage sludge digestion process, consisting of thermophilic aerobic digestion (TAD) followed by mesophilic anaerobic digestion (MAD), was developed for efficient sludge reduction and methane production. Using TAD as a biological pretreatment, the total volatile suspended solid reduction (VSSR) and methane production rate (MPR) in the MAD reactor were significantly improved. According to denaturing gradient gel electrophoresis (DGGE) analysis, the results indicated that the dominant bacteria species such as Ureibacillus thermophiles and Bacterium thermus in TAD were major routes for enhancing soluble organic matter. TAD pretreatment using a relatively short SRT of 1 day showed highly increased soluble organic products and positively affected an increment of bacteria populations which performed interrelated microbial metabolisms with methanogenic species in the MAD; consequently, a quantitative real-time PCR indicated greatly increased Methanosarcinales (acetate-utilizing methanogens) in the MAD, resulting in enhanced methane production. Copyright © 2013 Elsevier Ltd. All rights reserved.

Digesters and demographics: identifying support for anaerobic digesters on dairy farms.

PubMed

Sanders, D J; Roberts, M C; Ernst, S C; Thraen, C S

2010-11-01

The dairy industry in the United States is amidst a long-running trend toward fewer, larger dairy farms. This development has created a backlash in some communities over concerns such as odor, waste management, and environmental degradation. Separately, anaerobic digestion has advanced as a waste management technology that potentially offers solutions to some of these issues, providing odor control and a combustible biogas among other things. These digesters require significant capital investments. Voluntary consumer premiums for the renewable energy produced have been used in some instances as a means to move adoption of such systems toward financial feasibility. This project employed a survey to measure Ohio consumers' willingness to pay a premium for renewable energy produced by anaerobic digesters on dairy farms. Cluster analysis was used to segment consumers by willingness to pay, age, education, income, self-identified political inclination, and a composite variable that served as a proxy for respondents' environmental stewardship. Four distinctive groups emerged from the data. Older, less educated respondents were found to have the least amount of support for digesters on dairy farms, whereas politically liberal, environmentally proactive respondents demonstrated the strongest support. Well-educated, affluent respondents and young respondents fell between these 2 groups. Most large dairy farms are generally met with fairly negative responses from their local communities; in contrast, this research finds some popular support for anaerobic digestion technology. Going forward, establishing a positive link between support for anaerobic digesters and for their use on large dairies could open up a new route for less-contested large dairy farm developments. Evaluation of community demographics could become an important part of finding an optimal location for a large dairy farm. Copyright © 2010 American Dairy Science Association. Published by Elsevier Inc. All

Co-digestion of sewage sludge and sterilized solid slaughterhouse waste: methane production efficiency and process limitations.

PubMed

Pitk, Peep; Kaparaju, Prasad; Palatsi, Jordi; Affes, Rim; Vilu, Raivo

2013-04-01

The rendering product of Category 2 and 3 Animal By-Products is known as sterilized mass (SM) and it is mainly composed of fat and proteins, making it interesting substrate for anaerobic digestion. Batch and semi-continuous laboratory experiments were carried out to investigate the effect of SM addition in co-digestion with sewage sludge on methane production and possible process limitations. Results showed that SM addition in the feed mixture up to 5% (w/w), corresponding to 68.1% of the organic loading, increased methane production 5.7 times, without any indication of process inhibition. Further increase of SM addition at 7.5% (w/w) caused methane production decrease and volatile solids removal reduction, that was mainly related to remarkably increased free ammonia concentration in the digester of 596.5±68.6 gNH3 L(-1). Sterilized mass addition of 10% (w/w) caused intensive foaming, LCFA accumulation of 9172±701.2 mgCOD-LCFA g(-1) sample and termination of the experiment. Copyright © 2013 Elsevier Ltd. All rights reserved.

[The digestive characteristics of fishes (the biocenotic aspects)].

PubMed

Kuz'mina, V V

1996-03-01

The cavity, membrane and intracellular digestion is added by two additional types of digestion in the fish: a symbiont digestion and an induced autolysis. As the intensity of processes maintained by the enzyme systems of the victim and a symbiont depends upon the structure and conditions of the biocenosis, the latter are regarded as an ecological component. The enzymes of microflora and objects of feeding contribute much to digestive processes in fish and take part in the adaptation of their digestive system to the character of the food and specifics of the biocenosis.

Digestion and digestive-transport surfaces in cestodes and their fish hosts.

PubMed

Izvekova, G I; Kuperman, B I; Kuz'mina, V V

1997-12-01

The structural and functional organization of digestive-transport surfaces in some lower cestodes and their fish hosts was studied. It has been shown that the ultrastructure of cestode microtriches and fish enterocyte microvilli being the basis of membrane-linked digestion is quite similar. These organelles increase the digestive-transport surfaces both in helminths and fishes. However, the hydrolytic enzyme activity in helminths is usually 2-4 times lower than that of the fishes. Desorption (adsorption) characteristics of various hydrolases in helminths and fishes are also different. In helminths the easily desorbed fraction of each enzyme is always more abundant than in fishes. In contrast, the intensity of transport processes in helminths is higher when compared with fishes. The adaptation of digestive-transport surfaces and enzyme systems to feeding conditions is discussed.

Proteolytic Digestion and TiO2 Phosphopeptide Enrichment Microreactor for Fast MS Identification of Proteins.

PubMed

Deng, Jingren; Lazar, Iulia M

2016-04-01

The characterization of phosphorylation state(s) of a protein is best accomplished by using isolated or enriched phosphoprotein samples or their corresponding phosphopeptides. The process is typically time-consuming as, often, a combination of analytical approaches must be used. To facilitate throughput in the study of phosphoproteins, a microreactor that enables a novel strategy for performing fast proteolytic digestion and selective phosphopeptide enrichment was developed. The microreactor was fabricated using 100 μm i.d. fused-silica capillaries packed with 1-2 mm beds of C18 and/or TiO2 particles. Proteolytic digestion-only, phosphopeptide enrichment-only, and sequential proteolytic digestion/phosphopeptide enrichment microreactors were developed and tested with standard protein mixtures. The protein samples were adsorbed on the C18 particles, quickly digested with a proteolytic enzyme infused over the adsorbed proteins, and further eluted onto the TiO2 microreactor for enrichment in phosphopeptides. A number of parameters were optimized to speed up the digestion and enrichments processes, including microreactor dimensions, sample concentrations, digestion time, flow rates, buffer compositions, and pH. The effective time for the steps of proteolytic digestion and enrichment was less than 5 min. For simple samples, such as standard protein mixtures, this approach provided equivalent or better results than conventional bench-top methods, in terms of both enzymatic digestion and selectivity. Analysis times and reagent costs were reduced ~10- to 15-fold. Preliminary analysis of cell extracts and recombinant proteins indicated the feasibility of integration of these microreactors in more advanced workflows amenable for handling real-world biological samples. Graphical Abstract ᅟ.

Modified anaerobic digestion elutriated phased treatment for the anaerobic co-digestion of sewage sludge and food wastewater.

PubMed

Mo, Kyung; Lee, Wonbae; Kim, Moonil

2017-02-01

A modified anaerobic digestion elutriated phased treatment (MADEPT) process was developed for investigating anaerobic co-digestion of sewage sludge and food wastewater. The anaerobic digestion elutriated phased treatment (ADEPT) process is similar to a two-phase system, however, in which the effluent from a methanogenic reactor recycles into an acidogenic reactor to elutriate mainly dissolved organics. Although ADEPT could reduce reactor volume significantly, the unsolubilized solids should be wasted from the system. The MADEPT process combines thermo-alkali solubilization with ADEPT to improve anaerobic performance and to minimize the sludge disposal. It was determined that the optimal volume mixing ratio of sewage sludge and food wastewater was 4 : 1 for the anaerobic co-digestion. The removal efficiencies of total chemical oxygen demand, volatile solids, and volatile suspended solids in the MADEPT process were 73%, 70%, and 64%, respectively. However, those in the ADEPT process were only 48%, 37%, and 40%, respectively, at the same hydraulic retention time (HRT) of 7 days. The gas production of MADEPT was two times higher than that of ADEPT. The thermo-alkali solubilization increased the concentration of dissolved organics so that they could be effectively degraded in a short HRT, implying that MADEPT could improve the performance of ADEPT in anaerobic co-digestion.

Bioaccessibility of hydroxycinnamic acids and antioxidant capacity from sorghum bran thermally processed during simulated in vitro gastrointestinal digestion.

PubMed

Salazar-López, Norma Julieta; González-Aguilar, Gustavo A; Rouzaud-Sández, Ofelia; Robles-Sánchez, Maribel

2018-06-01

Sorghum is a source of hydroxycinnamic acids (HCA), which have shown antioxidant, anti-inflammatory and anti-proliferative capacities. However, a high proportion of them have low bioaccessibility due the complex structural disposition of the plant's cell wall. The effects of boiling and extrusion processes on sorghum bran and their effects on the antioxidant capacity and bioaccessibility of HCA during simulated in vitro gastrointestinal digestion were investigated. The bioaccessibility of phenolic compounds was significantly higher in extruded sorghum bran (38.4%) than that obtained by boiling (29.5%). This is consistent with the increase of the antioxidant capacity after in vitro digestion. In contrast, a low bioaccessibility of pure monomeric HCA was observed when they were exposed to in vitro gastrointestinal digestion. There were significant bioaccessibility reductions of 36.8, 19.5, 13.5, 62.1% for caffeic, ρ-coumaric, ferulic and sinapic acids, respectively, when unproccessed sorghum bran was added. Although the bioaccessibility of monomeric HCA was low, the total phenolic compounds and antioxidant capacity increased during the digestion simulation due to the thermal processes of extrusion and boiling. Extrusion and boiling could be utilized to produce food based on sorghum bran with biological potential.

Rectosigmoidian Involvement in Advanced-stage Ovarian Cancer – Intraoperative Decisions

PubMed Central

BACALBASA, NICOLAE; BALESCU, IRINA; DIMA, SIMONA

2017-01-01

Background/Aim: Ovarian cancer remains one of the most commonly encountered malignancies affecting women worldwide, that is unfortunately commonly diagnosed in advanced stages of the disease. In these stages, the tumoral process usually involves the surrounding viscera throughout contiguity or induces the apparition of distant metastases via peritoneal, lymphatic or hematogenous spread, multiple resections being needed in order to achieve a good control of the disease. Patients and Methods: In the present study, we present a case series of 12 patients in whom various surgical procedures on the rectosigmoidian loop were performed in order to achieve debulking surgery to no residual disease. Results: Digestive tract resections consisted of rectosigmoidian resection with left colostomy in three cases, low rectosigmoidian resections with anastomosis in eight cases and a stripping procedure of the peritoneal layer in one case. Conclusion: Due to the close proximity of the digestive and gynecological tract, advanced-stage ovarian tumors frequently involve the rectosigmoidian loop, imposing association of digestive tract surgical procedures. PMID:28882968

Effects of processing moisture on the physical properties and in vitro digestibility of starch and protein in extruded brown rice and pinto bean composite flours.

PubMed

Sumargo, Franklin; Gulati, Paridhi; Weier, Steven A; Clarke, Jennifer; Rose, Devin J

2016-11-15

The influence of pinto bean flour and processing moisture on the physical properties and in vitro digestibility of rice-bean extrudates has been investigated. Brown rice: pinto bean flour (0%, 15%, 30%, and 45% bean flour) were extruded under 5 moisture conditions (17.2%, 18.1%, 18.3%, 19.5%, and 20.1%). Physical properties [bulk density, unit density, radial expansion, axial expansion, overall expansion, specific volume, hardness, color, water solubility index, and water absorption index] and in vitro starch and protein digestibilities were determined. Increasing bean flour and processing moisture increased density and hardness while decreasing expansion. Rapidly digestible starch decreased and resistant starch increased as bean substitution and processing moisture increased. In vitro protein digestibility increased with increasing bean flour or with decreasing processing moisture. Incorporating bean flour into extruded snacks can negatively affect physical attributes (hardness, density, and expansion) while positively affecting in vitro starch (decrease) and protein (increase) digestibilities. Copyright © 2016 Elsevier Ltd. All rights reserved.

Enhancing Promotion, Tenure and Beyond: Faculty Socialization as a Cultural Process. ERIC Digest.

ERIC Educational Resources Information Center

Tierney, William G.; Rhoads, Robert A.

This digest is a brief summary of a longer monograph of the same title on the importance of understanding faculty socialization as a cultural process in the context of the current changes urged on higher education. A section on how faculty socialization is conceptualized adopts a view of culture in which culture shapes and is shaped by social…

Anaerobic co-digestion of sewage sludge and food waste using temperature-phased anaerobic digestion process.

PubMed

Kim, H W; Han, S K; Shin, H S

2004-01-01

This study was performed to overcome the low efficiency of anaerobic digestion of sewage sludge and food waste by combining temperature-phased digestion, sequencing batch operation, and co-digestion technology. It was demonstrated that the temperature-phased anaerobic sequencing batch reactor (TPASBR) system for the co-digestion of sewage sludge and food waste resulted in enhanced volatile solids (VS) reduction and methane production rate. At the organic loading rate (OLR) of 2.7 g VS/l/d, the TPASBR system showed the higher VS reduction (61.3%), CH4 yield (0.28 l/g VS(added)) and CH4 production rate (0.41 l CH4/l/d) than those (0.29 l CH4/l/d) of the mesophilic two-stage ASBR (MTSASBR). In the specific methanogenic activity (SMA) tests on thermophilic biomass of the TPASBR system, the average SMA of acetate (93 ml CH4/gVSS/d) was much higher than those of propionate (46 ml CH4/g VSS/d) and butyrate (76 ml CH4/g VSS/d). Also, higher specific hydrolytic activity (SHA, 217 mg COD/g VSS/d) of the biomass supported fast hydrolysis under thermophilic conditions. The track study revealed that the most active period of the 24 h cycle was between 6 and 12 h. The enhanced performance of the TPASBR system could be attributed to longer solids retention time, fast hydrolysis, higher CH4 conversion rate, and balanced nutrient condition of co-substrate. It was verified that this combination could be a promising and practical alternative for the simultaneous recycling of two types of organic fraction of municipal solid waste (OFMSW) with high stability.

Parameters affecting the stability of the digestate from a two-stage anaerobic process treating the organic fraction of municipal solid waste

DOE Office of Scientific and Technical Information (OSTI.GOV)

Trzcinski, Antoine P., E-mail: a.trzcinski05@ic.ac.uk; Stuckey, David C., E-mail: d.stuckey@ic.ac.uk

2011-07-15

This paper focused on the factors affecting the respiration rate of the digestate taken from a continuous anaerobic two-stage process treating the organic fraction of municipal solid waste (OFMSW). The process involved a hydrolytic reactor (HR) that produced a leachate fed to a submerged anaerobic membrane bioreactor (SAMBR). It was found that a volatile solids (VS) removal in the range 40-75% and an operating temperature in the HR between 21 and 35 {sup o}C resulted in digestates with similar respiration rates, with all digestates requiring 17 days of aeration before satisfying the British Standard Institution stability threshold of 16 mgmore » CO{sub 2} g VS{sup -1} day{sup -1}. Sanitization of the digestate at 65 {sup o}C for 7 days allowed a mature digestate to be obtained. At 4 g VS L{sup -1} d{sup -1} and Solid Retention Times (SRT) greater than 70 days, all the digestates emitted CO{sub 2} at a rate lower than 25 mg CO{sub 2} g VS{sup -1} d{sup -1} after 3 days of aeration, while at SRT lower than 20 days all the digestates displayed a respiration rate greater than 25 mg CO{sub 2} g VS{sup -1} d{sup -1}. The compliance criteria for Class I digestate set by the European Commission (EC) and British Standard Institution (BSI) could not be met because of nickel and chromium contamination, which was probably due to attrition of the stainless steel stirrer in the HR.« less

Early warning indicators for monitoring the process failure of anaerobic digestion system of food waste.

PubMed

Li, Lei; He, Qingming; Wei, Yunmei; He, Qin; Peng, Xuya

2014-11-01

To determine reliable state parameters which could be used as early warning indicators of process failure due to the acidification of anaerobic digestion of food waste, three mesophilic anaerobic digesters of food waste with different operation conditions were investigated. Such parameters as gas production, methane content, pH, concentrations of volatile fatty acid (VFA), alkalinity and their combined indicators were evaluated. Results revealed that operation conditions significantly affect the responses of parameters and thus the optimal early warning indicators of each reactor differ from each other. None of the single indicators was universally valid for all the systems. The universally valid indicators should combine several parameters to supply complementary information. A combination of total VFA, the ratio of VFA to total alkalinity (VFA/TA) and the ratio of bicarbonate alkalinity to total alkalinity (BA/TA) can reflect the metabolism of the digesting system and realize rapid and effective early warning. Copyright © 2014 Elsevier Ltd. All rights reserved.

Advanced information processing system

NASA Technical Reports Server (NTRS)

Lala, J. H.

1984-01-01

Design and performance details of the advanced information processing system (AIPS) for fault and damage tolerant data processing on aircraft and spacecraft are presented. AIPS comprises several computers distributed throughout the vehicle and linked by a damage tolerant data bus. Most I/O functions are available to all the computers, which run in a TDMA mode. Each computer performs separate specific tasks in normal operation and assumes other tasks in degraded modes. Redundant software assures that all fault monitoring, logging and reporting are automated, together with control functions. Redundant duplex links and damage-spread limitation provide the fault tolerance. Details of an advanced design of a laboratory-scale proof-of-concept system are described, including functional operations.

Reducing waste contamination from animal-processing plants by anaerobic thermophilic fermentation and by flesh fly digestion.

PubMed

Marchaim, U; Gelman, A; Braverman, Y

2003-01-01

There is currently no market in Israel for the large amounts of waste from fish- and poultry-processing plants. Therefore, this waste is incinerated, as part of the measures to prevent the spread of pathogens. Anaerobic methanogenic thermophilic fermentation (AMTF) of wastes from the cattle-slaughtering industry was examined previously, as an effective system to treat pathogenic bacteria, and in this article, we discuss a combined method of digestion by thermophilic anaerobic bacteria and by flesh flies, as a means of waste treatment. The AMTF process was applied to the wastes on a laboratory scale, and digestion by rearing of flesh fly (Phaenicia sericata) and housefly (Musca domestica) larvae on the untreated raw material was done on a small scale and showed remarkable weight conversion to larvae. The yield from degradation of poultry waste by flesh fly was 22.47% (SD = 3.89) and that from fish waste degradation was 35.34% (SD = 12.42), which is significantly higher than that from rearing houseflies on a regular rearing medium. Bacterial contents before and after thermophilic anaerobic digestion, as well as the changes in the chemical composition of the components during the rearing of larvae, were also examined.

Psychrophilic anaerobic digestion of guinea pig manure in low-cost tubular digesters at high altitude.

PubMed

Garfí, Marianna; Ferrer-Martí, Laia; Villegas, Vidal; Ferrer, Ivet

2011-05-01

Guinea pig is one of the most common livestock in rural communities of the Andes. The aim of this research was to study the anaerobic digestion of guinea pig manure in low-cost unheated tubular digesters at high altitude. To this end, the performance of two pilot digesters was monitored during 7 months; and two greenhouse designs were compared. In the dome roof digester the temperature and biogas production were significantly higher than in the shed roof digester. However, the biogas production rate was low (0.04 m(biogas)(3)m(digester)(-3) d(-1)), which is attributed to the low organic loading rate (0.6 kg(VS)m(digester)(-3)d(-1)) and temperature (23°C) of the system, among other factors. In a preliminary fertilization study, the potato yield per hectare was increased by 100% using the effluent as biofertilizer. Improving manure management techniques, increasing the organic loading rate and co digesting other substrates may be considered to enhance the process. Copyright © 2011 Elsevier Ltd. All rights reserved.

Impact of processing on in vitro digestion of milk from grazing organic and confined conventional herds

USDA-ARS?s Scientific Manuscript database

Debate on differences between milk from grazing and non-grazing cows has not addressed the effects that standard processing may have on milk digestibility. In this study, raw milk from grazing organic (ORG) and non-grazing conventional (CONV) herds was adjusted to 0 and 3.25% fat and processed as fo...

Waste biorefineries - integrating anaerobic digestion and microalgae cultivation for bioenergy production.

PubMed

Chen, Yi-di; Ho, Shih-Hsin; Nagarajan, Dillirani; Ren, Nan-Qi; Chang, Jo-Shu

2018-04-01

Commercialization of microalgal cultivation has been well realized in recent decades with the use of effective strains that can yield the target products, but it is still challenged by the high costs arising from mass production, harvesting, and further processing. Recently, more interest has been directed towards the utilization of waste resources, such as sludge digestate, to enhance the economic feasibility and sustainability of microalgae production. Anaerobic digestion for waste disposal and phototrophic microalgal cultivation are well-characterized technologies in both fields. However, integration of anaerobic digestion and microalgal cultivation to achieve substantial economic and environmental benefits is extremely limited, and thus deserves more attention and research effort. In particular, combining these two makes possible an ideal 'waste biorefinery' model, as the C/N/P content in the anaerobic digestate can be used to produce microalgal biomass that serves as feedstock for biofuels, while biogas upgrading can simultaneously be performed by phototrophic CO 2 fixation during microalgal growth. This review is thus aimed at elucidating recent advances as well as challenges and future directions with regard to waste biorefineries associated with the integration of anaerobic waste treatment and microalgal cultivation for bioenergy production. Copyright © 2017 Elsevier Ltd. All rights reserved.

Diversity Digest. Volume 9, Number 2

ERIC Educational Resources Information Center

Musil, Caryn McTighe, Ed.; Hovland, Kevin, Ed.

2005-01-01

Published by the Association of American Colleges and Universities, this issue of "Diversity Digest" focuses on institutional leadership and how it advances diversity in higher education. Articles presented in this issue include: (1) Intercultural Learning for Inclusive Excellence (Edgar Beckham); (2) Demanding, Attracting, and Developing…

The microstructure of starchy food modulates its digestibility.

PubMed

Tian, Jinhu; Ogawa, Yukiharu; Shi, John; Chen, Shiguo; Zhang, Huiling; Liu, Donghong; Ye, Xingqian

2018-06-05

Starch is the main carbohydrate in human nutrition and shows a range of desired food properties. It has been demonstrated that fast digestion of starchy food can induce many health issues (e.g., hyperglycaemia, diabetes, etc.); therefore, how to modulate its digestion is an interesting topic. Previous studies have revealed that the microstructure and digestibility of starchy food of different botanical origin or from multiple processes are quite different; modulating starch digestion by retaining or altering its microstructure may be effective. In the present review, the current knowledge of the relationship between microstructural changes to starchy food and its digestibility at molecular, cell and tissue, and food processing levels is summarized. New technologies focused on microstructure studies and ways to manipulate food microstructure to modulate starch digestibility are also reviewed. In particular, some insights focusing on the future study of microstructure and the digestibility of starchy food are also suggested.

Rectosigmoidian Involvement in Advanced-stage Ovarian Cancer - Intraoperative Decisions.

PubMed

Bacalbasa, Nicolae; Balescu, Irina; Dima, Simona

2017-01-01

Ovarian cancer remains one of the most commonly encountered malignancies affecting women worldwide, that is unfortunately commonly diagnosed in advanced stages of the disease. In these stages, the tumoral process usually involves the surrounding viscera throughout contiguity or induces the apparition of distant metastases via peritoneal, lymphatic or hematogenous spread, multiple resections being needed in order to achieve a good control of the disease. In the present study, we present a case series of 12 patients in whom various surgical procedures on the rectosigmoidian loop were performed in order to achieve debulking surgery to no residual disease. Digestive tract resections consisted of rectosigmoidian resection with left colostomy in three cases, low rectosigmoidian resections with anastomosis in eight cases and a stripping procedure of the peritoneal layer in one case. Due to the close proximity of the digestive and gynecological tract, advanced-stage ovarian tumors frequently involve the rectosigmoidian loop, imposing association of digestive tract surgical procedures. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

Robust interval-based regulation for anaerobic digestion processes.

PubMed

Alcaraz-González, V; Harmand, J; Rapaport, A; Steyer, J P; González-Alvarez, V; Pelayo-Ortiz, C

2005-01-01

A robust regulation law is applied to the stabilization of a class of biochemical reactors exhibiting partially known highly nonlinear dynamic behavior. An uncertain environment with the presence of unknown inputs is considered. Based on some structural and operational conditions, this regulation law is shown to exponentially stabilize the aforementioned bioreactors around a desired set-point. This approach is experimentally applied and validated on a pilot-scale (1 m3) anaerobic digestion process for the treatment of raw industrial wine distillery wastewater where the objective is the regulation of the chemical oxygen demand (COD) by using the dilution rate as the manipulated variable. Despite large disturbances on the input COD and state and parametric uncertainties, this regulation law gave excellent performances leading the output COD towards its set-point and keeping it inside a pre-specified interval.

Developing a vacuum thermal stripping - acid absorption process for ammonia recovery from anaerobic digester effluent.

PubMed

Ukwuani, Anayo T; Tao, Wendong

2016-12-01

To prevent acetoclastic methanogens from ammonia inhibition in anaerobic digestion of protein-rich substrates, ammonia needs to be removed or recovered from digestate. This paper presents an innovative ammonia recovery process that couples vacuum thermal stripping with acid absorption. Ammonia is stripped out of digestate boiling at a temperature below the normal boiling point due to vacuum. Stripped ammonia is absorbed to a sulfuric acid solution, forming ammonium sulfate crystals as a marketable product. Three common types of digestate were found to have boiling point temperature-vacuum curves similar to water. Seven combinations of boiling temperature and vacuum (50 °C 16.6 kPa, 58 °C 20.0 kPa, 65 °C 25.1 kPa, 70 °C 33.6 kPa, 80 °C 54.0 kPa, 90 °C 74.2 kPa, and 100 °C 101.3 kPa) were tested for batch stripping of ammonia in dairy manure digestate. 93.3-99.9% of ammonia was stripped in 3 h. The Lewis-Whitman model fitted ammonia stripping process well. Ammonia mass transfer coefficient was significantly higher at boiling temperature 65-100 °C and vacuum pressure 25.1-101.3 kPa than 50-58 °C and 16.6-20.0 kPa. The low ammonia saturation concentrations (0-24 mg N/L) suggested a large driving force to strip ammonia. The optimum boiling point temperature - vacuum pressure for ammonia recovery in a recirculation line of a mesophilic digester was 65 °C and 25.1 kPa, at which the ammonia mass transfer coefficient was as high as 37.3 mm/h. Installation of a demister and liquid trap could avoid negative effects of higher stripping temperature and stronger vacuum on formation of ammonium sulfate crystals. Pilot tests demonstrated that high-purity ammonium sulfate crystals could be produced by controlling sulfuric acid content and maintaining acid solution saturated with ammonium sulfate. Although volatile organic compounds such as cyclohexene were found in the final acid solutions, no volatile organic compounds were found in the recovered

Fungal fermentation on anaerobic digestate for lipid-based biofuel production.

PubMed

Zhong, Yuan; Liu, Zhiguo; Isaguirre, Christine; Liu, Yan; Liao, Wei

2016-01-01

Anaerobic digestate is the effluent from anaerobic digestion of organic wastes. It contains a significant amount of nutrients and lignocellulosic materials, even though anaerobic digestion consumed a large portion of organic matters in the wastes. Utilizing the nutrients and lignocellulosic materials in the digestate is critical to significantly improve efficiency of anaerobic digestion technology and generate value-added chemical and fuel products from the organic wastes. Therefore, this study focused on developing an integrated process that uses biogas energy to power fungal fermentation and converts remaining carbon sources, nutrients, and water in the digestate into biofuel precursor-lipid. The process contains two unit operations of anaerobic digestion and digestate utilization. The digestate utilization includes alkali treatment of the mixture feed of solid and liquid digestates, enzymatic hydrolysis for mono-sugar release, overliming detoxification, and fungal fermentation for lipid accumulation. The experimental results conclude that 5 h and 30 °C were the preferred conditions for the overliming detoxification regarding lipid accumulation of the following fungal cultivation. The repeated-batch fungal fermentation enhanced lipid accumulation, which led to a final lipid concentration of 3.16 g/L on the digestate with 10% dry matter. The mass and energy balance analysis further indicates that the digestate had enough water for the process uses and the biogas energy was able to balance the needs of individual unit operations. A fresh-water-free and energy-positive process of lipid production from anaerobic digestate was achieved by integrating anaerobic digestion and fungal fermentation. The integration addresses the issues that both biofuel industry and waste management encounter-high water and energy demand of biofuel precursor production and few digestate utilization approaches of organic waste treatment.

Advanced concepts in joining by conventional processes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Edwards, G.R.; Fasching-James, A.A.; Onsoien, M.I.

1994-12-31

Innovations which can be made to conventional arc welding processes so that advanced materials can be more efficiently joined are considered. Three examples are discussed: (1) GTA welding of iron aluminides, (2) GMA welding of advanced steels, and (3) SMA welding of structural steels. Advanced materials present new challenges for the materials joining specialist. The three examples discussed in this paper demonstrate, however, that modest but creative alterations of conventional GTAW, GMAW, or SMAW processes can provide new and better controls for solving advanced materials joining problems.

Kenaf Bast Fibers—Part I: Hermetical Alkali Digestion

DOE PAGES

Shi, Jinshu; Shi, Sheldon Q.; Barnes, H. Michael; ...

2011-01-01

The objective of this study was to develop a hermetical alkali digestion process to obtain single cellulosic fibers from kenaf bast. Kenaf bast were hermetically digested into single fiber using a 5% sodium hydroxide solution for one hour at four different temperatures (80 ° C, 110 ° C, 130 ° C, and 160 ° C). The hermetical digestion process used in this study produced fibers with high cellulose content (84.2–92.3%) due to the removal of lignin and hemicelluloses. The surface hardness and elastic modulus of the fibers digested at 130 ° C and 160 ° C were improved significantly comparedmore » with those digested at 80 ° C. The tensile modulus and tensile strength of the individual fibers reduced as the digestion temperature increased from 110 ° C to 160 ° C. Micropores were generated in fiber cell wall when the fibers were digested at 130 ° C and 160 ° C. The studies on the composites that were made from polypropylene reinforced with the digested fibers indicated that the compatibility between the digested fibers and polypropylene matrix was poor.« less

Sequential anaerobic/aerobic digestion for enhanced sludge stabilization: comparison of the process performance for mixed and waste sludge [corrected].

PubMed

Tomei, M Concetta; Carozza, Nicola Antonello

2015-05-01

Sequential anaerobic-aerobic digestion has been demonstrated as a promising alternative for enhanced sludge stabilization. In this paper, a feasibility study of the sequential digestion applied to real waste activated sludge (WAS) and mixed sludge is presented. Process performance is evaluated in terms of total solid (TS) and volatile solid (VS) removal, biogas production, and dewaterability trend in the anaerobic and double-stage digested sludge. In the proposed digestion lay out, the aerobic stage was operated with intermittent aeration to reduce the nitrogen load recycled to the wastewater treatment plant (WWTP). Experimental results showed a very good performance of the sequential digestion process for both waste and mixed sludge, even if, given its better digestibility, higher efficiencies are observed for mixed sludge. VS removal efficiencies in the anaerobic stage were 48 and 50% for waste and mixed sludge, respectively, while a significant additional improvement of the VS removal of 25% for WAS and 45% for mixed sludge has been obtained in the aerobic stage. The post-aerobic stage, operated with intermittent aeration, was also efficient in nitrogen removal, providing a significant decrease of the nitrogen content in the supernatant: nitrification efficiencies of 90 and 97% and denitrification efficiencies of 62 and 70% have been obtained for secondary and mixed sludges, respectively. A positive effect due to the aerobic stage was also observed on the sludge dewaterability in both cases. Biogas production, expressed as Nm(3)/(kgVSdestroyed), was 0.54 for waste and 0.82 for mixed sludge and is in the range of values reported in the literature in spite of the low anaerobic sludge retention time of 15 days.

Influence of thermophilic aerobic digestion as a sludge pre-treatment and solids retention time of mesophilic anaerobic digestion on the methane production, sludge digestion and microbial communities in a sequential digestion process.

PubMed

Jang, Hyun Min; Cho, Hyun Uk; Park, Sang Kyu; Ha, Jeong Hyub; Park, Jong Moon

2014-01-01

In this study, the changes in sludge reduction, methane production and microbial community structures in a process involving two-stage thermophilic aerobic digestion (TAD) and mesophilic anaerobic digestion (MAD) under different solid retention times (SRTs) between 10 and 40 days were investigated. The TAD reactor (RTAD) was operated with a 1-day SRT and the MAD reactor (RMAD) was operated at three different SRTs: 39, 19 and 9 days. For a comparison, control MAD (RCONTROL) was operated at three different SRTs of 40, 20 and 10 days. Our results reveal that the sequential TAD-MAD process has about 42% higher methane production rate (MPR) and 15% higher TCOD removal than those of RCONTROL when the SRT decreased from 40 to 20 days. Denaturing gradient gel electrophoresis (DGGE) and real-time PCR results indicate that RMAD maintained a more diverse bacteria and archaea population compared to RCONTROL, due to the application of the biological TAD pre-treatment process. In RTAD, Ureibacillus thermophiles and Bacterium thermus were the major contributors to the increase in soluble organic matter. In contrast, Methanosaeta concilii, a strictly aceticlastic methanogen, showed the highest population during the operation of overall SRTs in RMAD. Interestingly, as the SRT decreased to 20 days, syntrophic VFA oxidizing bacteria, Clostridium ultunense sp., and a hydrogenotrophic methanogen, Methanobacterium beijingense were detected in RMAD and RCONTROL. Meanwhile, the proportion of archaea to total microbe in RMAD and RCONTROL shows highest values of 10.5 and 6.5% at 20-d SRT operation, respectively. Collectively, these results demonstrate that the increased COD removal and methane production at different SRTs in RMAD might be attributed to the increased synergism among microbial species by improving the hydrolysis of the rate limiting step in sludge with the help of the biological TAD pre-treatment. Copyright © 2013 Elsevier Ltd. All rights reserved.

Advanced planning for ISS payload ground processing

NASA Astrophysics Data System (ADS)

Page, Kimberly A.

2000-01-01

Ground processing at John F. Kennedy Space Center (KSC) is the concluding phase of the payload/flight hardware development process and is the final opportunity to ensure safe and successful recognition of mission objectives. Planning for the ground processing of on-orbit flight hardware elements and payloads for the International Space Station is a responsibility taken seriously at KSC. Realizing that entering into this operational environment can be an enormous undertaking for a payload customer, KSC continually works to improve this process by instituting new/improved services for payload developer/owner, applying state-of-the-art technologies to the advanced planning process, and incorporating lessons learned for payload ground processing planning to ensure complete customer satisfaction. This paper will present an overview of the KSC advanced planning activities for ISS hardware/payload ground processing. It will focus on when and how KSC begins to interact with the payload developer/owner, how that interaction changes (and grows) throughout the planning process, and how KSC ensures that advanced planning is successfully implemented at the launch site. It will also briefly consider the type of advance planning conducted by the launch site that is transparent to the payload user but essential to the successful processing of the payload (i.e. resource allocation, executing documentation, etc.) .

Cancer stem cells of the digestive system.

PubMed

Colvin, Hugh S; Nishida, Naohiro; Koseki, Jun; Konno, Masamitsu; Kawamoto, Koichi; Tsunekuni, Kenta; Doki, Yuichiro; Mori, Masaki; Ishii, Hideshi

2014-12-01

Stem cells of the digestive system are ideal in many ways for research, given they are abundant, highly proliferative and have a uniform structural arrangement. This in turn has enormously aided the research of cancer stem cells of the digestive system, which is now shaping our understanding of cancer stem cells. In this review, the recent advances in the understanding of cancer stem cells of the digestive system have been summarized, including aspects such as their identification, origin, cell-cycle dormancy, relationship with epithelial-mesenchymal transition, cellular metabolism and the underlying molecular mechanisms. Newly acquired knowledge concerning cancer stem cells have led to the development of novel cancer therapeutics with provisional yet encouraging results. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Advances in Process Control.

ERIC Educational Resources Information Center

Morrison, David L.; And Others

1982-01-01

Advances in electronics and computer science have enabled industries (pulp/paper, iron/steel, petroleum/chemical) to attain better control of their processes with resulting increases in quality, productivity, profitability, and compliance with government regulations. (JN)

The conversion of anaerobic digestion waste into biofuels via a novel Thermo-Catalytic Reforming process.

PubMed

Neumann, Johannes; Meyer, Johannes; Ouadi, Miloud; Apfelbacher, Andreas; Binder, Samir; Hornung, Andreas

2016-01-01

Producing energy from biomass and other organic waste residues is essential for sustainable development. Fraunhofer UMSICHT has developed a novel reactor which introduces the Thermo-Catalytic Reforming (TCR®) process. The TCR® is a process which can convert any type of biomass and organic feedstocks into a variety of energy products (char, bio-oil and permanent gases). The aim of this work was to demonstrate this technology using digestate as the feedstock and to quantify the results from the post reforming step. The temperature of a post reformer was varied to achieve optimised fuel products. The hydrogen rich permanent gases produced were maximised at a post reforming temperature of 1023 K. The highly de-oxygenated liquid bio-oil produced contained a calorific value of 35.2 MJ/kg, with significantly improved fuel physical properties, low viscosity and acid number. Overall digestate showed a high potential as feedstock in the Thermo-Catalytic Reforming to produce pyrolysis fuel products of superior quality. Copyright © 2015 Elsevier Ltd. All rights reserved.

Comparing the effect of homogenization and heat processing on the properties and in vitro digestion of milk from organic and conventional dairy herds.

PubMed

Van Hekken, D L; Tunick, M H; Ren, D X; Tomasula, P M

2017-08-01

We compared the effects of homogenization and heat processing on the chemical and in vitro digestion traits of milk from organic and conventional herds. Raw milk from organic (>50% of dry matter intake from pasture) and conventional (no access to pasture) farms were adjusted to commercial whole and nonfat milk fat standards, and processed with or without homogenization, and with high-temperature-short-time or UHT pasteurization. The milk then underwent in vitro gastrointestinal digestion. Comparison of milk from organic and conventional herds showed that the milks responded to processing in similar ways. General composition was the same among the whole milk samples and among the nonfat milk samples. Protein profiles were similar, with intact caseins and whey proteins predominant and only minor amounts of peptides. Whole milk samples from grazing cows contained higher levels of α-linolenic (C18:3), vaccenic (C18:1 trans), and conjugated linoleic acids, and lower levels of palmitic (C16:0) and stearic (C18:0) acids than samples from nongrazing cows. Processing had no effect on conjugated linoleic acid and linolenic acid levels in milk, although homogenization resulted in higher levels of C8 to C14 saturated fatty acids. Of the 9 volatile compounds evaluated, milk from grazing cows contained lower levels of 2-butanone than milk from nongrazing cows, and milk from both farms showed spikes for heptanal in UHT samples and spikes for butanoic, octanoic, nonanoic, and N-decanoic acids in homogenized samples. At the start of in vitro digestion, nonfat raw and pasteurized milk samples formed the largest acid clots, and organic milk clots were larger than conventional milk clots; UHT whole milk formed the smallest clots. Milk digests from grazing cows had lower levels of free fatty acids than digests from nongrazing cows. In vitro proteolysis was similar in milk from both farms and resulted in 85 to 95% digestibility. Overall, milk from organic/grass-fed and conventional

Combined mesophilic anaerobic and thermophilic aerobic digestion process for high-strength food wastewater to increase removal efficiency and reduce sludge discharge.

PubMed

Jang, H M; Park, S K; Ha, J H; Park, J M

2014-01-01

In this study, a process that combines the mesophilic anaerobic digestion (MAD) process with thermophilic aerobic digestion (TAD) for high-strength food wastewater (FWW) treatment was developed to examine the removal of organic matter and methane production. All effluent discharged from the MAD process was separated into solid and liquid portions. The liquid part was discarded and the sludge part was passed to the TAD process for further degradation. Then, the digested sludge from the TAD process was recycled back to the MAD unit to achieve low sludge discharge from the combined process. The reactor combination was operated in two phases: during Phase I, 40 d of total hydraulic retention time (HRT) was applied; during Phase II, 20 d was applied. HRT of the TAD process was fixed at 5 d. For a comparison, a control process (single-stage MAD) was operated with the same HRTs of the combined process. Our results indicated that the combined process showed over 90% total solids, volatile solids and chemical oxygen demand removal efficiencies. In addition, the combined process showed a significantly higher methane production rate than that of the control process. Consequently, the experimental data demonstrated that the combined MAD-TAD process was successfully employed for high-strength FWW treatment with highly efficient organic matter reduction and methane production.

Effect of heat and homogenization on in vitro digestion of milk.

PubMed

Tunick, Michael H; Ren, Daxi X; Van Hekken, Diane L; Bonnaillie, Laetitia; Paul, Moushumi; Kwoczak, Raymond; Tomasula, Peggy M

2016-06-01

Central to commercial fluid milk processing is the use of high temperature, short time (HTST) pasteurization to ensure the safety and quality of milk, and homogenization to prevent creaming of fat-containing milk. Ultra-high-temperature sterilization is also applied to milk and is typically used to extend the shelf life of refrigerated, specialty milk products or to provide shelf-stable milk. The structures of the milk proteins and lipids are affected by processing but little information is available on the effects of the individual processes or sequences of processes on digestibility. In this study, raw whole milk was subjected to homogenization, HTST pasteurization, and homogenization followed by HTST or UHT processing. Raw skim milk was subjected to the same heating regimens. In vitro gastrointestinal digestion using a fasting model was then used to detect the processing-induced changes in the proteins and lipids. Using sodium dodecyl sulfate-PAGE, gastric pepsin digestion of the milk samples showed rapid elimination of the casein and α-lactalbumin bands, persistence of the β-lactoglobulin bands, and appearance of casein and whey peptide bands. The bands for β-lactoglobulin were eliminated within the first 15min of intestinal pancreatin digestion. The remaining proteins and peptides of raw, HTST, and UHT skim samples were digested rapidly within the first 15min of intestinal digestion, but intestinal digestion of raw and HTST pasteurized whole milk showed some persistence of the peptides throughout digestion. The availability of more lipid droplets upon homogenization, with greater surface area available for interaction with the peptides, led to persistence of the smaller peptide bands and thus slower intestinal digestion when followed by HTST pasteurization but not by UHT processing, in which the denatured proteins may be more accessible to the digestive enzymes. Homogenization and heat processing also affected the ζ-potential and free fatty acid release

Deterministic processes guide long-term synchronised population dynamics in replicate anaerobic digesters

PubMed Central

Vanwonterghem, Inka; Jensen, Paul D; Dennis, Paul G; Hugenholtz, Philip; Rabaey, Korneel; Tyson, Gene W

2014-01-01

A replicate long-term experiment was conducted using anaerobic digestion (AD) as a model process to determine the relative role of niche and neutral theory on microbial community assembly, and to link community dynamics to system performance. AD is performed by a complex network of microorganisms and process stability relies entirely on the synergistic interactions between populations belonging to different functional guilds. In this study, three independent replicate anaerobic digesters were seeded with the same diverse inoculum, supplied with a model substrate, α-cellulose, and operated for 362 days at a 10-day hydraulic residence time under mesophilic conditions. Selective pressure imposed by the operational conditions and model substrate caused large reproducible changes in community composition including an overall decrease in richness in the first month of operation, followed by synchronised population dynamics that correlated with changes in reactor performance. This included the synchronised emergence and decline of distinct Ruminococcus phylotypes at day 148, and emergence of a Clostridium and Methanosaeta phylotype at day 178, when performance became stable in all reactors. These data suggest that many dynamic functional niches are predictably filled by phylogenetically coherent populations over long time scales. Neutral theory would predict that a complex community with a high degree of recognised functional redundancy would lead to stochastic changes in populations and community divergence over time. We conclude that deterministic processes may play a larger role in microbial community dynamics than currently appreciated, and under controlled conditions it may be possible to reliably predict community structural and functional changes over time. PMID:24739627

Effect of high hydrostatic pressure processing on in vitro digestion of milk proteins and fats

USDA-ARS?s Scientific Manuscript database

The use of high hydrostatic pressure processing (HPP) is increasing in popularity in the food industry. Its ability to modify milk proteins and fats suggests that it may be useful in creating foods that suppress appetite; however, its effect on the digestibility of proteins and fats is unclear. The...

Fate of Trace Metals in Anaerobic Digestion.

PubMed

Fermoso, F G; van Hullebusch, E D; Guibaud, G; Collins, G; Svensson, B H; Carliell-Marquet, C; Vink, J P M; Esposito, G; Frunzo, L

2015-01-01

A challenging, and largely uncharted, area of research in the field of anaerobic digestion science and technology is in understanding the roles of trace metals in enabling biogas production. This is a major knowledge gap and a multifaceted problem involving metal chemistry; physical interactions of metal and solids; microbiology; and technology optimization. Moreover, the fate of trace metals, and the chemical speciation and transport of trace metals in environments--often agricultural lands receiving discharge waters from anaerobic digestion processes--simultaneously represents challenges for environmental protection and opportunities to close process loops in anaerobic digestion.

Optimizing the Logistics of Anaerobic Digestion of Manure

NASA Astrophysics Data System (ADS)

Ghafoori, Emad; Flynn, Peter C.

Electrical power production from the combustion of biogas from anaerobic digestion (AD) of manure is a means of recovering energy from animal waste. We evaluate the lowest cost method of moving material to and from centralized AD plants serving multiple confined feeding operations. Two areas are modeled, Lethbridge County, Alberta, Canada, an area of concentrated beef cattle feedlots, and Red Deer County, Alberta, a mixed-farming area with hog, dairy, chicken and beef cattle farms, and feedlots. We evaluate two types of AD plant: ones that return digestate to the source confined feeding operation for land spreading (current technology), and ones that process digestate to produce solid fertilizer and a dischargeable water stream (technology under development). We evaluate manure and digestate trucking, trucking of manure with return of digestate by pipelines, and pipelining of manure plus digestate. We compare the overall cost of power from these scenarios to farm or feedlot-based AD units. For a centralized AD plant with digestate return for land spreading the most economical transport option for manure plus digestate is by truck for the mixed-farming area and by pipelines for the concentrated feedlot area. For a centralized AD plant with digestate processing, the most economical transport option is trucking of manure for both cases.

Advanced information processing system for advanced launch system: Avionics architecture synthesis

NASA Technical Reports Server (NTRS)

Lala, Jaynarayan H.; Harper, Richard E.; Jaskowiak, Kenneth R.; Rosch, Gene; Alger, Linda S.; Schor, Andrei L.

1991-01-01

The Advanced Information Processing System (AIPS) is a fault-tolerant distributed computer system architecture that was developed to meet the real time computational needs of advanced aerospace vehicles. One such vehicle is the Advanced Launch System (ALS) being developed jointly by NASA and the Department of Defense to launch heavy payloads into low earth orbit at one tenth the cost (per pound of payload) of the current launch vehicles. An avionics architecture that utilizes the AIPS hardware and software building blocks was synthesized for ALS. The AIPS for ALS architecture synthesis process starting with the ALS mission requirements and ending with an analysis of the candidate ALS avionics architecture is described.

Anaerobic co-digestion of dairy manure and potato waste

NASA Astrophysics Data System (ADS)

Yadanaparthi, Sai Krishna Reddy

Dairy and potato are two important agricultural commodities in Idaho. Both the dairy and potato processing industries produce a huge amount of waste which could cause environmental pollution. To minimize the impact of potential pollution associated with dairy manure (DM) and potato waste (PW), anaerobic co-digestion has been considered as one of the best treatment process. The purpose of this research is to evaluate the anaerobic co-digestion of dairy manure and potato waste in terms of process stability, biogas generation, construction and operating costs, and potential revenue. For this purpose, I conducted 1) a literature review, 2) a lab study on anaerobic co-digestion of dairy manure and potato waste at three different temperature ranges (ambient (20-25°C), mesophilic (35-37°C) and thermophilic (55-57°C) with five mixing ratios (DM:PW-100:0, 90:10, 80:20, 60:40, 40:60), and 3) a financial analysis for anaerobic digesters based on assumed different capital costs and the results from the lab co-digestion study. The literature review indicates that several types of organic waste were co-digested with DM. Dairy manure is a suitable base matter for the co-digestion process in terms of digestion process stability and methane (CH4) production (Chapter 2). The lab tests showed that co-digestion of DM with PW was better than digestion of DM alone in terms of biogas and CH4 productions (Chapter 3). The financial analysis reveals DM and PW can be used as substrate for full size anaerobic digesters to generate positive cash flow within a ten year time period. Based on this research, the following conclusions and recommendations were made: ▸ The ratio of DM:PW-80:20 is recommended at thermophilic temperatures and the ratio of DM:PW-90:10 was recommended at mesophilic temperatures for optimum biogas and CH4 productions. ▸ In cases of anaerobic digesters operated with electricity generation equipment (generators), low cost plug flow digesters (capital cost of 600/cow

Enhanced anaerobic digestion of waste activated sludge digestion by the addition of zero valent iron.

PubMed

Feng, Yinghong; Zhang, Yaobin; Quan, Xie; Chen, Suo

2014-04-01

Anaerobic digestion is promising technology to recover energy from waste activated sludge. However, the sludge digestion is limited by its low efficiency of hydrolysis-acidification. Zero valent iron (ZVI) as a reducing material is expected to enhance anaerobic process including the hydrolysis-acidification process. Considering that, ZVI was added into an anaerobic sludge digestion system to accelerate the sludge digestion in this study. The results indicated that ZVI effectively enhanced the decomposition of protein and cellulose, the two main components of the sludge. Compared to the control test without ZVI, the degradation of protein increased 21.9% and the volatile fatty acids production increased 37.3% with adding ZVI. More acetate and less propionate are found during the hydrolysis-acidification with ZVI. The activities of several key enzymes in the hydrolysis and acidification increased 0.6-1 time. ZVI made the methane production raise 43.5% and sludge reduction ratio increase 12.2 percent points. Fluorescence in situ hybridization analysis showed that the abundances of hydrogen-consuming microorganisms including homoacetogens and hydrogenotrophic methanogens with ZVI were higher than the control, which reduced the H2 accumulation to create a beneficial condition for the sludge digestion in thermodynamics. Copyright © 2013 Elsevier Ltd. All rights reserved.

Anaerobic digestion of post-hydrothermal liquefaction wastewater for improved energy efficiency of hydrothermal bioenergy processes.

PubMed

Zhou, Yan; Schideman, Lance; Zheng, Mingxia; Martin-Ryals, Ana; Li, Peng; Tommaso, Giovana; Zhang, Yuanhui

2015-01-01

Hydrothermal liquefaction (HTL) is a promising process for converting wet biomass and organic wastes into bio-crude oil. It also produces an aqueous product referred to as post-hydrothermal liquefaction wastewater (PHWW) containing up to 40% of the original feedstock carbon, which reduces the overall energy efficiency of the HTL process. This study investigated the feasibility of using anaerobic digestion (AD) to treat PHWW, with the aid of activated carbon. Results showed that successful AD occurred at relatively low concentrations of PHWW (≤ 6.7%), producing a biogas yield of 0.5 ml/mg CODremoved, and ∼53% energy recovery efficiency. Higher concentrations of PHWW (≥13.3%) had an inhibitory effect on the AD process, as indicated by delayed, slower, or no biogas production. Activated carbon was shown to effectively mitigate this inhibitory effect by enhancing biogas production and allowing digestion to proceed at higher PHWW concentrations (up to 33.3%), likely due to sequestering toxic organic compounds. The addition of activated carbon also increased the net energy recovery efficiency of AD with a relatively high concentration of PHWW (33.3%), taking into account the energy for producing activated carbon. These results suggest that AD is a feasible approach to treat PHWW, and to improve the energy efficiency of the HTL processes.

Effect of Food Waste Co-Digestion on Digestion, Dewatering, and Cake Quality.

PubMed

Higgins, Matthew; Rajagopalan, Ganesh; Miller, Andre; Brown, Jeffrey; Beightol, Steven

2017-01-01

  The objective of this study was to evaluate the effect of food waste addition on anaerobic digestion performance as well as downstream parameters including dewatering, cake quality, and filtrate quality. Laboratory-scale digesters were fed processed food waste at rates of 25%, 45%, and 65% increased chemical oxygen demand (COD) loading rates compared to a control fed only primary and secondary solids. The specific methane yield increased from 370 L CH4/kg VSadded for the control to 410, 440, and 470 L CH4/kg VSadded for the 25, 45, and 65% food waste addition, respectively. The cake solids after dewatering were all higher for the food waste digesters compared to the control, with the highest cake solids being measured for the 45% food-waste loading. Compared to the control digester, the biosolids odorant concentration increased for the lowest dose of food waste. Odorant concentrations were below detection for the highest food waste loading.

Anammox process for nitrogen removal from anaerobically digested fish canning effluents.

PubMed

Dapena-Mora, A; Campos, J L; Mosquera-Corral, A; Méndez, R

2006-01-01

The Anammox process was used to treat the effluent generated in an anaerobic digester which treated the wastewater from a fish cannery once previously processed in a Sharon reactor. The effluents generated from the anaerobic digestion are characterised by their high ammonium content (700-1000 g NH4+ -Nm(-3)), organic carbon content (1000-1300 g TOCm(-3)) and salinity up to 8,000-10,000 g NaCl m(-3). In the Sharon reactor, approximately 50% of the NH4+ -N was oxidised to NO2- -N via partial nitrification. The effluent of the Sharon step was fed to the Anammox reactor which treated an averaged nitrogen loading rate of 500 g N m(-3) x d(-1). The system reached an averaged nitrogen removal efficiency of 68%, mainly limited due to the nonstoichiometric relation, for the Anammox process, between the ammonium and nitrite added in the feeding. The Anammox reactor bacterial population distribution, followed by FISH analysis and batch activity assays, did not change significantly despite the continuous entrance to the system of aerobic ammonium oxidisers coming from the Sharon reactor. Most of the bacteria corresponded to the Anammox population and the rest with slight variable shares to the ammonia oxidisers. The Anammox reactor showed an unexpected robustness despite the continuous variations in the influent composition regarding ammonium and nitrite concentrations. Only in the period when NO2- -N concentration was higher than the NH4+ -N concentration did the process destabilise and it took 14 days until the nitrogen removal percentage decreased to 34% with concentrations in the effluent of 340g NH4+ -N m(-3) and 440 g NO2- -N m(-3), respectively. Based on these results, it seems that the Sharon-Anammox system can be applied for the treatment of industrial wastewaters with high nitrogen load and salt concentration with an appropriate control of the NO2- -N/NH4+ -N ratio.

Excess digestive capacity in predators reflects a life of feast and famine.

PubMed

Armstrong, Jonathan B; Schindler, Daniel E

2011-07-06

A central challenge for predators is achieving positive energy balance when prey are spatially and temporally heterogeneous. Ecological heterogeneity produces evolutionary trade-offs in the physiological design of predators; this is because the ability to capitalize on pulses of food abundance requires high capacity for food-processing, yet maintaining such capacity imposes energetic costs that are taxing during periods of food scarcity. Recent advances in physiology show that when variation in foraging opportunities is predictable, animals may adjust energetic trade-offs by rapidly modulating their digestive system to track variation in foraging opportunities. However, it is increasingly recognized that foraging opportunities for animals are unpredictable, which should favour animals that maintain a capacity for food-processing that exceeds average levels of consumption (loads). Despite this basic principle of quantitative evolutionary design, estimates of digestive load:capacity ratios in wild animals are virtually non-existent. Here we provide an extensive assessment of load:capacity ratios for the digestive systems of predators in the wild, compiling 639 estimates across 38 species of fish. We found that piscine predators typically maintain the physiological capacity to feed at daily rates 2-3 times higher than what they experience on average. A numerical simulation of the trade-off between food-processing capacity and metabolic cost suggests that the observed level of physiological opportunism is profitable only if predator-prey encounters, and thus predator energy budgets, are far more variable in nature than currently assumed.

Evaluation of the Removal of Indicator Bacteria from Domestic Sludge Processed by Autothermal Thermophilic Aerobic Digestion (ATAD)

PubMed Central

Piterina, Anna V.; Bartlett, John; Pembroke, Tony J.

2010-01-01

The degradation of sludge solids in an insulated reactor during Autothermal Thermophilic Aerobic Digestion (ATAD) processing results in auto-heating, thermal treatment and total solids reduction, however, the ability to eliminate pathogenic organisms has not been analysed under large scale process conditions. We evaluated the ATAD process over a period of one year in a two stage, full scale Irish ATAD plant established in Killarney and treating mixed primary and secondary sludge, by examining the sludge microbiologically at various stages during and following ATAD processing to determine its ability to eliminate indicator organisms. Salmonella spp. (pathogen) and fecal-coliform (indicator) densities were well below the limits used to validate class A biosolids in the final product. Enteric pathogens present at inlet were deactivated during the ATAD process and were not detected in the final product using both traditional microbial culture and molecular phylogenetic techniques. A high DNase activity was detected in the bulk sludge during the thermophilic digestion stage which may be responsible for the rapid turn over of DNA from lysed cells and the removal of mobile DNA. These results offer assurance for the safe use of ATAD sludge as a soil supplement following processing. PMID:20948933

Evaluation of the removal of indicator bacteria from domestic sludge processed by Autothermal Thermophilic Aerobic Digestion (ATAD).

PubMed

Piterina, Anna V; Bartlett, John; Pembroke, Tony J

2010-09-01

The degradation of sludge solids in an insulated reactor during Autothermal Thermophilic Aerobic Digestion (ATAD) processing results in auto-heating, thermal treatment and total solids reduction, however, the ability to eliminate pathogenic organisms has not been analysed under large scale process conditions. We evaluated the ATAD process over a period of one year in a two stage, full scale Irish ATAD plant established in Killarney and treating mixed primary and secondary sludge, by examining the sludge microbiologically at various stages during and following ATAD processing to determine its ability to eliminate indicator organisms. Salmonella spp. (pathogen) and fecal-coliform (indicator) densities were well below the limits used to validate class A biosolids in the final product. Enteric pathogens present at inlet were deactivated during the ATAD process and were not detected in the final product using both traditional microbial culture and molecular phylogenetic techniques. A high DNase activity was detected in the bulk sludge during the thermophilic digestion stage which may be responsible for the rapid turn over of DNA from lysed cells and the removal of mobile DNA. These results offer assurance for the safe use of ATAD sludge as a soil supplement following processing.

The effect of thermal hydrolysis pretreatment on the anaerobic degradation of nonylphenol and short-chain nonylphenol ethoxylates in digested biosolids.

PubMed

McNamara, P J; Wilson, C A; Wogen, M T; Murthy, S N; Novak, J T; Novak, P J

2012-06-01

The presence of micropollutants can be a concern for land application of biosolids. Of particular interest are nonylphenol diethoxylate (NP(2)EO), nonylphenol monoethoxylate (NP(1)EO), and nonylphenol (NP), collectively referred to as NPE, which accumulate in anaerobically digested biosolids and are subject to regulation based on the environmental risks associated with them. Because biosolids are a valuable nutrient resource, it is essential that we understand how various treatment processes impact the fate of NPE in biosolids. Thermal hydrolysis (TH) coupled with mesophilic anaerobic digestion (MAD) is an advanced digestion process that destroys pathogens in biosolids and increases methane yields and volatile solids destruction. We investigated the impact of thermal hydrolysis pretreatment on the subsequent biodegradation of NPE in digested biosolids. Biosolids were treated with TH, anaerobic digestion, and aerobic digestion in laboratory-scale reactors, and NPE were analyzed in the influent and effluent of the digesters. NP(2)EO and NP(1)EO have been observed to degrade to the more estrogenic NP under anaerobic conditions; therefore, changes in the ratio of NP:NPE were of interest. The increase in NP:NPE following MAD was 56%; the average increase of this ratio in four sets of TH-MAD samples, however, was only 24.6 ± 3.1%. In addition, TH experiments performed in pure water verified that, during TH, the high temperature and pressure alone did not directly destroy NPE; TH experiments with NP added to sludge also showed that NP was not destroyed by the high temperature and pressure of TH when in a more complex sludge matrix. The post-aerobic digestion phases removed NPE, regardless of whether TH pretreatment occurred. This research indicates that changes in biosolids processing can have impacts beyond just gas production and solids destruction. Copyright © 2012 Elsevier Ltd. All rights reserved.

Co-treatment of fruit and vegetable waste in sludge digesters. An analysis of the relationship among bio-methane generation, process stability and digestate phytotoxicity.

PubMed

Di Maria, Francesco; Sordi, Alessio; Cirulli, Giuseppe; Gigliotti, Giovanni; Massaccesi, Luisa; Cucina, Mirko

2014-09-01

The co-digestion of a variable amount of fruit and vegetable waste in a waste mixed sludge digester was investigated using a pilot scale apparatus. The organic loading rate (OLR) was increased from 1.46 kg VS/m(3) day to 2.8 kg VS/m(3) day. The hydraulic retention time was reduced from 14 days to about 10 days. Specific bio-methane production increased from about 90 NL/kg VS to the maximum value of about 430 NL/kg VS when OLR was increased from 1.46 kg VS/m(3) day to 2.1 kg VS/m(3) day. A higher OLR caused an excessive reduction in the hydraulic retention time, enhancing microorganism wash out. Process stability evaluated by the total volatile fatty acids concentration (mg/l) to the alkalinity buffer capacity (eq. mg/l CaCO3) ratio (i.e. FOS/TAC) criterion was <0.1 indicating high stability for OLR <2.46 kg VS/m(3 )day. For higher OLR, FOS/TAC increased rapidly. Residual phytotoxicty of the digestate evaluated by the germination index (GI) (%) was quite constant for OLR<2.46 kg VS/m(3)day, which is lower than the 60% limit, indicating an acceptable toxicity level for crops. For OLR>2.46 kg VS/m(3) day, GI decreased rapidly. This corresponding trend between FOS/TAC and GI was further investigated by the definition of the GI ratio (GIR) parameter. Comparison between GIR and FOS/TAC suggests that GI could be a suitable criterion for evaluating process stability. Copyright © 2014 Elsevier Ltd. All rights reserved.

Anaerobic Digestion.

PubMed

Liebetrau, Jan; Sträuber, Heike; Kretzschmar, Jörg; Denysenko, Velina; Nelles, Michael

2017-04-09

The term anaerobic digestion usually refers to the microbial conversion of organic material to biogas, which mainly consists of methane and carbon dioxide. The technical application of the naturally-occurring process is used to provide a renewable energy carrier and - as the substrate is often waste material - to reduce the organic matter content of the substrate prior to disposal.Applications can be found in sewage sludge treatment, the treatment of industrial and municipal solid wastes and wastewaters (including landfill gas utilization), and the conversion of agricultural residues and energy crops.For biorefinery concepts, the anaerobic digestion (AD) process is, on the one hand, an option to treat organic residues from other production processes. Concomitant effects are the reduction of organic carbon within the treated substance, the conversion of nitrogen and sulfur components, and the production of an energy-rich gas - the biogas. On the other hand, the multistep conversion of complex organic material offers the possibility of interrupting the conversion chain and locking out intermediates for utilization as basic material within the chemical industry.

Proteases and nucleases involved in the biphasic digestion process of the brown marmorated stink bug, Halyomorpha halys (Hemiptera: Pentatomidae).

PubMed

Lomate, Purushottam R; Bonning, Bryony C

2018-07-01

Management of the brown marmorated stink bug, Halyomorpha halys (Hemiptera: Pentatomidae), an invasive, agricultural pest in the United States, has presented significant challenges. This polyphagous insect uses both extra-oral and gut-based digestion thwarting protein- or nucleotide-based control strategies. The objective of this study was to biochemically characterize the digestive enzymes (proteases and nucleases) from the saliva, salivary gland and the gut of H. halys. Enzyme profiles for the two tissues and saliva radically differ: The pH optimum for proteases in the gut was six, with cysteine proteases predominant. In contrast, the alkaline pH optima for protease activity in the salivary gland (8-10) and saliva (7) reflected abundant serine protease and cathepsin activities. RNase enzymes were most abundant in saliva, while dsRNase and DNase activities were higher in the salivary gland and saliva compared to those in the gut. These very different enzyme profiles highlight the biphasic digestive system used by this invasive species for efficient processing of plant nutrients. Knowledge of H. halys digestive physiology will allow for counteractive measures targeting digestive enzymes or for appropriate protection of protein- or nucleotide-based management options targeting this pest. © 2018 Wiley Periodicals, Inc.

A comparison of process performance during the anaerobic mono- and co-digestion of slaughterhouse waste through different operational modes.

PubMed

Pagés-Díaz, Jhosané; Pereda-Reyes, Ileana; Sanz, Jose Luis; Lundin, Magnus; Taherzadeh, Mohammad J; Horváth, Ilona Sárvári

2018-02-01

The use of consecutive feeding was applied to investigate the response of the microbial biomass to a second addition of substrates in terms of biodegradation using batch tests as a promising alternative to predict the behavior of the process. Anaerobic digestion (AD) of the slaughterhouse waste (SB) and its co-digestion with manure (M), various crops (VC), and municipal solid waste were evaluated. The results were then correlated to previous findings obtained by the authors for similar mixtures in batch and semi-continuous operation modes. AD of the SB failed showing total inhibition after a second feeding. Co-digestion of the SB+M showed a significant improvement for all of the response variables investigated after the second feeding, while co-digestion of the SB+VC resulted in a decline in all of these response variables. Similar patterns were previously detected, during both the batch and the semi-continuous modes. Copyright © 2017. Published by Elsevier B.V.

In vivo digestion of bovine milk fat globules: effect of processing and interfacial structural changes. I. Gastric digestion.

PubMed

Gallier, Sophie; Cui, Jack; Olson, Trent D; Rutherfurd, Shane M; Ye, Aiqian; Moughan, Paul J; Singh, Harjinder

2013-12-01

The aim was to study the in vivo gastric digestion of fat globules in bovine cream from raw, pasteurised or pasteurised and homogenised milk. Fasted rats were gavaged once and chyme samples were collected after 30, 120 and 180 min post-gavage. Proteins from raw (RC) and pasteurised (PC) creams appeared to be digested faster and to a greater extent. Free fatty acids (FAs) increased throughout the 3h postprandial period. Short and medium chain FAs were released more rapidly than long chain FAs which were hydrolysed to a greater degree from PC. The size of the fat globules of all creams increased in the stomach. Protein aggregates were observed in pasteurised and homogenised cream chyme. Protrusions, probably caused by the accumulation of insoluble lipolytic products, appeared at the surface of the globules in RC and PC chyme. Overall, PC proteins and lipids appeared to be digested to a greater extent. Copyright © 2013 Elsevier Ltd. All rights reserved.

Modelling of Two-Stage Methane Digestion With Pretreatment of Biomass

NASA Astrophysics Data System (ADS)

Dychko, A.; Remez, N.; Opolinskyi, I.; Kraychuk, S.; Ostapchuk, N.; Yevtieieva, L.

2018-04-01

Systems of anaerobic digestion should be used for processing of organic waste. Managing the process of anaerobic recycling of organic waste requires reliable predicting of biogas production. Development of mathematical model of process of organic waste digestion allows determining the rate of biogas output at the two-stage process of anaerobic digestion considering the first stage. Verification of Konto's model, based on the studied anaerobic processing of organic waste, is implemented. The dependencies of biogas output and its rate from time are set and may be used to predict the process of anaerobic processing of organic waste.

The protein composition of the digestive fluid from the venus flytrap sheds light on prey digestion mechanisms.

PubMed

Schulze, Waltraud X; Sanggaard, Kristian W; Kreuzer, Ines; Knudsen, Anders D; Bemm, Felix; Thøgersen, Ida B; Bräutigam, Andrea; Thomsen, Line R; Schliesky, Simon; Dyrlund, Thomas F; Escalante-Perez, Maria; Becker, Dirk; Schultz, Jörg; Karring, Henrik; Weber, Andreas; Højrup, Peter; Hedrich, Rainer; Enghild, Jan J

2012-11-01

The Venus flytrap (Dionaea muscipula) is one of the most well-known carnivorous plants because of its unique ability to capture small animals, usually insects or spiders, through a unique snap-trapping mechanism. The animals are subsequently killed and digested so that the plants can assimilate nutrients, as they grow in mineral-deficient soils. We deep sequenced the cDNA from Dionaea traps to obtain transcript libraries, which were used in the mass spectrometry-based identification of the proteins secreted during digestion. The identified proteins consisted of peroxidases, nucleases, phosphatases, phospholipases, a glucanase, chitinases, and proteolytic enzymes, including four cysteine proteases, two aspartic proteases, and a serine carboxypeptidase. The majority of the most abundant proteins were categorized as pathogenesis-related proteins, suggesting that the plant's digestive system evolved from defense-related processes. This in-depth characterization of a highly specialized secreted fluid from a carnivorous plant provides new information about the plant's prey digestion mechanism and the evolutionary processes driving its defense pathways and nutrient acquisition.

Economic viability of anaerobic digestion

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wellinger, A.

1996-01-01

The industrial application of anaerobic digestion is a relatively new, yet proven waste treatment technology. Anaerobic digestion reduces and upgrades organic waste, and is a good way to control air pollution as it reduces methane and nitrous gas emissions. For environmental and energy considerations, anaerobic digestion is a nearly perfect waste treatment process. However, its economic viability is still in question. A number of parameters - type of waste (solid or liquid), digester system, facility size, product quality and end use, environmental requirements, cost of alternative treatments (including labor), and interest rates - define the investment and operating costs ofmore » an anaerobic digestion facility. Therefore, identical facilities that treat the same amount and type of waste may, depending on location, legislation, and end product characteristics, reveal radically different costs. A good approach for evaluating the economics of anaerobic digestion is to compare it to treatment techniques such as aeration or conventional sewage treatment (for industrial wastewater), or composting and incineration (for solid organic waste). For example, the cost (per ton of waste) of in-vessel composting with biofilters is somewhat higher than that of anaerobic digestion, but the investment costs 1 1/2 to 2 times more than either composting or anaerobic digestion. Two distinct advantages of anaerobic digestion are: (1) it requires less land than either composting or incinerating, which translates into lower costs and milder environmental and community impacts (especially in densely populated areas); and (2) it produces net energy, which can be used to operate the facility or sold to nearby industries.« less

Advanced Polymer Processing Facility

DOE Office of Scientific and Technical Information (OSTI.GOV)

Muenchausen, Ross E.

Some conclusions of this presentation are: (1) Radiation-assisted nanotechnology applications will continue to grow; (2) The APPF will provide a unique focus for radiolytic processing of nanomaterials in support of DOE-DP, other DOE and advanced manufacturing initiatives; (3) {gamma}, X-ray, e-beam and ion beam processing will increasingly be applied for 'green' manufacturing of nanomaterials and nanocomposites; and (4) Biomedical science and engineering may ultimately be the biggest application area for radiation-assisted nanotechnology development.

Methods of ammonia removal in anaerobic digestion: a review.

PubMed

Krakat, Niclas; Demirel, Burak; Anjum, Reshma; Dietz, Donna

2017-10-01

The anaerobic digestion of substrates with high ammonia content has always been a bottleneck in the methanisation process of biomasses. Since microbial communities in anaerobic digesters are sensitive to free ammonia at certain conditions, the digestion of nitrogen-rich substrates such as livestock wastes may result in inhibition/toxicity eventually leading to process failures, unless appropriate engineering precautions are taken. There are many different options reported in literature to remove ammonia from anaerobic digesters to achieve a safe and stable process so that along with high methane yields, a good quality of effluents can also be obtained. Conventional techniques to remove ammonia include physical/chemical methods, immobilization and adaptation of microorganisms, while novel methods include ultrasonication, microwave, hollow fiber membranes and microbial fuel cell applications. This paper discusses conventional and novel methods of ammonia removal from anaerobic digesters using nitrogen-rich substrates, with particular focus on recent literature available about this topic.

Simulating Dinosaur Digestion in the Classroom.

ERIC Educational Resources Information Center

Peczkis, Jan

1992-01-01

Describes an activity for use with a chapter on dinosaurs, prehistoric life, or digestion in which children make simulated dinosaur stomachs to gain hands-on experience about the theory of gastroliths, or stomach stones. Presents teacher information about the digestive processes in birds and dinosaurs. Discusses materials needed, objectives,…

Project T.E.A.M. (Technical Education Advancement Modules). Advanced Statistical Process Control.

ERIC Educational Resources Information Center

Dunlap, Dale

This instructional guide, one of a series developed by the Technical Education Advancement Modules (TEAM) project, is a 20-hour advanced statistical process control (SPC) and quality improvement course designed to develop the following competencies: (1) understanding quality systems; (2) knowing the process; (3) solving quality problems; and (4)…

Current perspective on assessing site of digestion in ruminants.

PubMed

Merchen, N R; Elizalde, J C; Drackley, J K

1997-08-01

The site of nutrient digestion in the gastrointestinal tract of ruminants affects nutrient availability and the nature of digestive end-products supplied to the host animal. Methods to study site of digestion in vivo provide a tool to obtain data that enhance the ability to interpret or predict animal responses to some feeding practices. Examples are discussed for which site of digestion data provided insights that might not have been evident from other approaches. The use of site of digestion techniques may provide interpretation regarding digestion of N by ruminants different from those derived from measurement of total tract N digestion. Site of digestion measurements have been particularly important in studying effects of heat processing of protein sources and in understanding the nature of digestion of N in high-quality, fresh forages. Moreover, site of digestion techniques have been instrumental in interpreting the influences of supplemental fat sources on ruminal digestion and ruminal biohydrogenation and small intestinal digestion of long-chain fatty acids.

Enhancement of methane production in mesophilic anaerobic digestion of secondary sewage sludge by advanced thermal hydrolysis pretreatment.

PubMed

Abelleira-Pereira, Jose M; Pérez-Elvira, Sara I; Sánchez-Oneto, Jezabel; de la Cruz, Roberto; Portela, Juan R; Nebot, Enrique

2015-03-15

Studies on the development and evolution of anaerobic digestion (AD) pretreatments are nowadays becoming widespread, due to the outstanding benefits that these processes could entail in the management of sewage sludge. Production of sewage sludge in wastewater treatment plants (WWTPs) is becoming an extremely important environmental issue. The work presented in this paper is a continuation of our previous studies with the aim of understanding and developing the advanced thermal hydrolysis (ATH) process. ATH is a novel AD pretreatment based on a thermal hydrolysis (TH) process plus hydrogen peroxide (H2O2) addition that takes advantage of a peroxidation/direct steam injection synergistic effect. The main goal of the present research was to compare the performance of TH and ATH, conducted at a wide range of operating conditions, as pretreatments of mesophilic AD with an emphasis on methane production enhancement as a key parameter and its connection with the sludge solubilization. Results showed that both TH and ATH patently improved methane production in subsequent mesophilic BMP (biochemical methane potential) tests in comparison with BMP control tests (raw secondary sewage sludge). Besides other interesting results and discussions, a promising result was obtained since ATH, operated at temperature (115 °C), pretreatment time (5 min) and pressure (1 bar) considerably below those typically used in TH (170 °C, 30 min, 8 bar), managed to enhance the methane production in subsequent mesophilic BMP tests [biodegradability factor (fB) = cumulative CH4production/cumulative CH4production (Control) = 1.51 ± 0.01] to quite similar levels than conventional TH pretreatment [fB = 1.52 ± 0.03]. Copyright © 2014 Elsevier Ltd. All rights reserved.

Optimised anaerobic treatment of house-sorted biodegradable waste and slaughterhouse waste in a high loaded half technical scale digester.

PubMed

Resch, C; Grasmug, M; Smeets, W; Braun, R; Kirchmayr, R

2006-01-01

Anaerobic co-digestion of organic wastes from households, slaughterhouses and meat processing industries was optimised in a half technical scale plant. The plant was operated for 130 days using two different substrates under organic loading rates of 10 and 12 kgCOD.m(-3).d(-1). Since the substrates were rich in fat and protein components (TKN: 12 g.kg(-1) the treatment was challenging. The process was monitored on-line and in the laboratory. It was demonstrated that an intensive and stable co-digestion of partly hydrolysed organic waste and protein rich slaughterhouse waste can be achieved in the balance of inconsistent pH and buffering NH4-N. In the first experimental period the reduction of the substrate COD was almost complete in an overall stable process (COD reduction >82%). In the second period methane productivity increased, but certain intermediate products accumulated constantly. Process design options for a second digestion phase for advanced degradation were investigated. Potential causes for slow and reduced propionic and valeric acid degradation were assessed. Recommendations for full-scale process implementation can be made from the experimental results reported. The highly loaded and stable codigestion of these substrates may be a good technical and economic treatment alternative.

College-Bound Digest.

ERIC Educational Resources Information Center

Who's Who among American High School Students, Lake Forest, IL.

The college admissions process and the college selection process are complex and much debated procedures which confront more than 50% of high school seniors in the United States. The purpose of this digest is to help students explore options available in choosing a suitable postsecondary education. For example the advantages of large or small…

Biotechnology Education and the Internet. ERIC Digest.

ERIC Educational Resources Information Center

Lee, Thomas

The world of modern biotechnology is based on recent developments in molecular biology, especially those in genetic engineering. Since this is a relatively new and rapidly advancing field of study, there are few traditional sources of information and activities. This digest highlights biotechnology resources including those that can be found on…

A Guide for Developing Standard Operating Job Procedures for the Digestion Process Wastewater Treatment Facility. SOJP No. 10.

ERIC Educational Resources Information Center

Schwing, Carl M.

This guide describes standard operating job procedures for the digestion process of wastewater treatment facilities. This process is for reducing the volume of sludge to be treated in subsequent units and to reduce the volatile content of sludge. The guide gives step-by-step instructions for pre-startup, startup, continuous operating, shutdown,…

Anaerobic Digestion Alters Copper and Zinc Speciation.

PubMed

Legros, Samuel; Levard, Clément; Marcato-Romain, Claire-Emmanuelle; Guiresse, Maritxu; Doelsch, Emmanuel

2017-09-19

Anaerobic digestion is a widely used organic waste treatment process. However, little is known on how it could alter the speciation of contaminants in organic waste. This study was focused on determining the influence of anaerobic digestion on the speciation of copper and zinc, two metals that generally occur at high concentration in organic waste. Copper and zinc speciation was investigated by X-ray absorption spectroscopy in four different raw organic wastes (predigestion) and their digested counterparts (postdigestion, i.e., digestates). The results highlighted an increase in the digestates of the proportion of amorphous or nanostructured copper sulfides as well as amorphous or nanostructured zinc sulfides and zinc phosphate as compared to raw waste. We therefore suggest that the environmental fate of these elements would be different when spreading either digestates or raw waste on cropland.

Archaeal community dynamics and abiotic characteristics in a mesophilic anaerobic co-digestion process treating fruit and vegetable processing waste sludge with chopped fresh artichoke waste.

PubMed

Ros, M; Franke-Whittle, I H; Morales, A B; Insam, H; Ayuso, M; Pascual, J A

2013-05-01

This study evaluated the feasibility of obtaining methane in anaerobic digestion (AD) from the waste products generated by the processing of fruit and vegetables. During the first phase (0-55 d) of the AD using sludge from fruit and vegetable processing, an average value of 244±88 L kg(-1) dry matter d(-1)of biogas production was obtained, and methane content reached 65% of the biogas. Co-digestion with chopped fresh artichoke wastes in a second phase (55-71 d) enhanced biogas production, and resulted in an average value of 354±68 L kg(-1) dry matter d(-1), with higher methane content (more than 70%). The archaeal community involved in methane production was studied using the ANAEROCHIP microarray and real-time PCR. Results indicated that species of Methanosaeta and Methanosarcina were important during the AD process. Methanosarcina numbers increased after the addition of chopped fresh artichoke, while Methanosaeta numbers decreased. Copyright © 2013 Elsevier Ltd. All rights reserved.

Advanced processing for high-bandwidth sensor systems

NASA Astrophysics Data System (ADS)

Szymanski, John J.; Blain, Phil C.; Bloch, Jeffrey J.; Brislawn, Christopher M.; Brumby, Steven P.; Cafferty, Maureen M.; Dunham, Mark E.; Frigo, Janette R.; Gokhale, Maya; Harvey, Neal R.; Kenyon, Garrett; Kim, Won-Ha; Layne, J.; Lavenier, Dominique D.; McCabe, Kevin P.; Mitchell, Melanie; Moore, Kurt R.; Perkins, Simon J.; Porter, Reid B.; Robinson, S.; Salazar, Alfonso; Theiler, James P.; Young, Aaron C.

2000-11-01

Compute performance and algorithm design are key problems of image processing and scientific computing in general. For example, imaging spectrometers are capable of producing data in hundreds of spectral bands with millions of pixels. These data sets show great promise for remote sensing applications, but require new and computationally intensive processing. The goal of the Deployable Adaptive Processing Systems (DAPS) project at Los Alamos National Laboratory is to develop advanced processing hardware and algorithms for high-bandwidth sensor applications. The project has produced electronics for processing multi- and hyper-spectral sensor data, as well as LIDAR data, while employing processing elements using a variety of technologies. The project team is currently working on reconfigurable computing technology and advanced feature extraction techniques, with an emphasis on their application to image and RF signal processing. This paper presents reconfigurable computing technology and advanced feature extraction algorithm work and their application to multi- and hyperspectral image processing. Related projects on genetic algorithms as applied to image processing will be introduced, as will the collaboration between the DAPS project and the DARPA Adaptive Computing Systems program. Further details are presented in other talks during this conference and in other conferences taking place during this symposium.

Conductive heating and microwave hydrolysis under identical heating profiles for advanced anaerobic digestion of municipal sludge.

PubMed

Mehdizadeh, Seyedeh Neda; Eskicioglu, Cigdem; Bobowski, Jake; Johnson, Thomas

2013-09-15

Microwave (2.45 GHz, 1200 W) and conventional heating (custom pressure vessel) pretreatments were applied to dewatered municipal waste sludge (18% total solids) using identical heating profiles that span a wide range of temperatures (80-160 °C). Fourteen lab-scale semi-continuous digesters were set up to optimize the energy (methane) output and sludge retention time (SRT) requirements of untreated (control) and thermally pretreated anaerobic digesters operated under mesophilic and thermophilic temperatures. Both pretreatment methods indicated that in the pretreatment range of 80-160 °C, temperature was a statistically significant factor (p-value < 0.05) for increasing solubilization of chemical oxygen demand and biopolymers (proteins, sugars, humic acids) of the waste sludge. However, the type of pretreatment method, i.e. microwave versus conventional heating, had no statistically significant effect (p-value >0.05) on sludge solubilization. With the exception of the control digesters at a 5-d SRT, all control and pretreated digesters achieved steady state at all three SRTs, corresponding to volumetric organic loading rates of 1.74-6.96 g chemical oxygen demand/L/d. At an SRT of 5 d, both mesophilic and thermophilic controls stopped producing biogas after 20 d of operation with total volatile fatty acids concentrations exceeding 1818 mg/L at pH <5.64 for mesophilic and 2853 mg/L at pH <7.02 for thermophilic controls, while the pretreated digesters continued producing biogas. Furthermore, relative (to control) organic removal efficiencies dramatically increased as SRT was shortened from 20 to 10 and then 5 d, indicating that the control digesters were challenged as the organic loading rate was increased. Energy analysis showed that, at an elevated temperature of 160 °C, the amount of methane recovered was not enough to compensate for the energy input. Among the digesters with positive net energy productions, control and pretreated digesters at 80 °C were more

Evaluation of the inclusion of soybean oil and soybean processing by-products to soybean meal on nutrient composition and digestibility in swine and poultry.

PubMed

Bruce, K J; Karr-Lilienthal, L K; Zinn, K E; Pope, L L; Mahan, D C; Fastinger, N D; Watts, M; Utterback, P L; Parsons, C M; Castaneda, E O; Ellis, M; Fahey, G C

2006-06-01

This experiment was designed to evaluate the effects of selected soybean (SB) processing byproducts (gums, oil, soapstock, weeds/trash) when added back to soybean meal (SBM) during processing on the resulting nutrient composition, protein quality, nutrient digestibility by swine, and true metabolizable energy (TMEn) content and standardized AA digestibility by poultry. To measure ileal DM and nutrient digestibility, pigs were surgically fitted with a T-cannula in the distal ileum. The concentration of TMEn and the standardized AA digestibility by poultry were determined using the precision fed cecectomized rooster assay. Treatments in the swine experiment included SBM with no by-products; SBM with 1% gum; SBM with 3% gum; SBM with 0.5% soapstock; SBM with 1.5% soapstock; SBM with 2% weeds/trash; SBM with a combination of 3% gum, 1.5% soapstock, and 2% weeds/trash; SBM with 5.4% soybean oil; and roasted SB. A 10 x 10 Latin square design was utilized. The experiment was conducted at the University of Illinois, Urbana-Champaign, and at The Ohio State University, Columbus. In the swine experiment, apparent ileal DM, OM, CP, and AA digestibilities were reduced (P < 0.05) when pigs consumed the combination by-product diet compared with the diet containing no by-products. Apparent ileal digestibilities of DM, CP, and total essential, total nonessential, and total AA were lower (P < 0.05) for any diet containing by-products compared with the diet with no by-products. Apparent ileal digestibilities of DM, OM, CP, and AA were lower (P < 0.05) for the roasted SB-compared with the SB oil-containing diet. In the rooster experiment, TMEn values were greater (P < 0.05) for roasted SB compared with SBM with no by-products and increased linearly as the addition of soapstock increased. Individual, total essential, total nonessential, and total AA digestibilities were lower (P < 0.05) for roosters fed roasted SB versus SBM devoid of by-products. Gums, soapstock, and weeds

Anaerobic digestion foaming causes--a review.

PubMed

Ganidi, Nafsika; Tyrrel, Sean; Cartmell, Elise

2009-12-01

Anaerobic digestion foaming has been encountered in several sewage treatment plants in the UK. Foaming has raised major concerns for the water companies due to significant impacts on process efficiency and operational costs. Several foaming causes have been identified over the past few years by researchers. However, the supporting experimental information is limited and in some cases absent. The present report aims to provide a detailed review of the current anaerobic digestion foaming problem and to identify gaps in knowledge regarding the theory of foam formation in anaerobic digesters.

Anaerobic digestion of municipal solid waste: Utility of process residues as a soil amendment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rivard, C.J.; Nagle, N.J.; Kay, B.D.

1995-12-31

Tuna processing wastes (sludges high in fat, oil, and grease [FOG]) and municipal solid waste (MSW) generated on Tutuila Island, American Samoa, represent an ongoing disposal challenge. The biological conversion of the organic fraction of these wastes to useful products, including methane and fertilizer-grade residue, through anaerobic high-solids digestion is currently in scale-up development. The suitability of the anaerobic digestion residues as a soil amendment was evaluated through extensive chemical analysis and greenhouse studies using corn as an indicator crop. Additionally, native Samoan soil was used to evaluate the specific application rates for the compost. Experiments established that anaerobic residuesmore » increase crop yields in direct proportion to increases in the application rate. Additionally, nutrient saturation was not demonstrated within the range of application rates evaluated for the Samoan soil. Beyond nutrient supplementation, organic residue amendment to Samoan soil imparts enhanced water and nutrient-binding capacities.« less

Identification and quantification of microbial populations in activated sludge and anaerobic digestion processes.

PubMed

Reyes, M; Borrás, L; Seco, A; Ferrer, J

2015-01-01

Eight different phenotypes were studied in an activated sludge process (AeR) and anaerobic digester (AnD) in a full-scale wastewater treatment plant by means of fluorescent in situ hybridization (FISH) and automated FISH quantification software. The phenotypes were ammonia-oxidizing bacteria, nitrite-oxidizing bacteria, denitrifying bacteria, phosphate-accumulating organisms (PAO), glycogen-accumulating organisms (GAO), sulphate-reducing bacteria (SRB), methanotrophic bacteria and methanogenic archaea. Some findings were unexpected: (a) Presence of PAO, GAO and denitrifiers in the AeR possibly due to unexpected environmental conditions caused by oxygen deficiencies or its ability to survive aerobically; (b) presence of SRB in the AeR due to high sulphate content of wastewater intake and possibly also due to digested sludge being recycled back into the primary clarifier; (c) presence of methanogenic archaea in the AeR, which can be explained by the recirculation of digested sludge and its ability to survive periods of high oxygen levels; (d) presence of denitrifying bacteria in the AnD which cannot be fully explained because the nitrate level in the AnD was not measured. However, other authors reported the existence of denitrifiers in environments where nitrate or oxygen was not present suggesting that denitrifiers can survive in nitrate-free anaerobic environments by carrying out low-level fermentation; (e) the results of this paper are relevant because of the focus on the identification of nearly all the significant bacterial and archaeal groups of microorganisms with a known phenotype involved in the biological wastewater treatment.

Proceedings of the signature series event of the international society for cellular therapy: "Advancements in cellular therapies and regenerative medicine in digestive diseases," London, United Kingdom, May 3, 2017.

PubMed

Ciccocioppo, Rachele; Dos Santos, Claudia C; Baumgart, Daniel C; Cangemi, Giuseppina C; Cardinale, Vincenzo; Ciacci, Carolina; De Coppi, Paolo; Haldar, Debashis; Klersy, Catherine; Nostro, M Cristina; Ott, Michael; Piemonti, Lorenzo; Tomei, Alice A; Uygun, Basak; Vetrano, Stefania; Orlando, Giuseppe

2018-03-01

A summary of the First Signature Series Event, "Advancements in Cellular Therapies and Regenerative Medicine for Digestive Diseases," held on May 3, 2017, in London, United Kingdom, is presented. Twelve speakers from three continents covered major topics in the areas of cellular therapy and regenerative medicine applied to liver and gastrointestinal medicine as well as to diabetes mellitus. Highlights from their presentations, together with an overview of the global impact of digestive diseases and a proposal for a shared online collection and data-monitoring platform tool, are included in this proceedings. Although growing evidence demonstrate the feasibility and safety of exploiting cell-based technologies for the treatment of digestive diseases, regulatory and methodological obstacles will need to be overcome before the successful implementation in the clinic of these novel attractive therapeutic strategies. Copyright © 2017 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

Application of Pineapple Juice in the Fish Digestion Process for Carcinogenic Liver Fluke Metacercaria Collection

PubMed Central

Sripan, Panupan; Aukkanimart, Ratchadawan; Boonmars, Thidarut; Pranee, Sriraj; Songsri, Jiraporn; Boueroy, Parichart; Khueangchaingkhwang, Sukhonthip; Pumhirunroj, Benjamabhorn; Artchayasawat, Atchara

2017-01-01

Pepsin is common digestive enzyme used for fish digestion in the laboratory to collect trematode metacercariae. In a field study, to survey the infected fish is needed a huge yield of pepsin and it is very expensive. Therefore, our purpose of this study was to investigate the candidate enzyme from pineapple juice which has a digestive enzyme called bromelain, a mixture of proteolytic enzymes, to digest fish in order to harvest metacercariae. Fish were divided into 2 groups: one group in which metacercariae were harvested using acid pepsin as a control and other groups in which the fish was digested using fresh pineapple juices. The results showed that pineapple juice is able to digest fish similarly to pepsin. The Pattavia pineapple juice had the highest number of metacercariae similar to the control. For Trat Si Thong pineapple juice, we found the number of metacercariae was less than control. This result suggests that the Pattavia pineapple juice was optimal juice for fish digestion to metacercaria collection and can be used instread of pepsin acid. PMID:28441786

Dietary acrylamide: What happens during digestion.

PubMed

Sansano, M; Heredia, A; Peinado, I; Andrés, A

2017-12-15

Acrylamide is a well-known potentially carcinogen compound formed during thermal processing as an intermediate of Maillard reactions. Three objectives were addressed: the impact of gastric digestion on acrylamide content of French Fries, chips, chicken nuggets, onions rings, breakfast cereals, biscuits, crackers, instant coffee and coffee substitute; the acrylamide content evolution during gastrointestinal digestion of French fries and chips; and the effectiveness of blanching and air-frying on acrylamide mitigation after gastrointestinal digestion. A significant increase (p-value <0.05) in acrylamide content was observed for most of the products after gastric digestion (maximum registered for sweet biscuits, from 30±8 to 150±48µg/kg). However, at the end of the intestinal stage, acrylamide values were statistically similar (p-value=0.132) for French fries and lower than the initial values (before digestion) in potato chips (p-value=0.027). Finally, the low acrylamide content found in blanched and air-fried samples, remained still lower than for deep fried samples even after gastrointestinal digestion. Copyright © 2017 Elsevier Ltd. All rights reserved.

Modeling of digestive processes in the stomach as a Fluid-Structure Interaction (FSI) phenomenon

NASA Astrophysics Data System (ADS)

Acharya, Shashank; Kou, Wenjun; Kahrilas, Peter J.; Pandolfino, John E.; Patankar, Neelesh A.

2017-11-01

The process of digestion in the gastro-intestinal (GI) tract is a complex mechanical and chemical process. Digestion in the stomach involves substantial mixing and breakup of food into smaller particles by muscular activity. In this work, we have developed a fully resolved model of the stomach (along with the esophagus) and its various muscle groups that deform the wall to agitate the contents inside. We use the Immersed Boundary finite-element method to model this FSI problem. From the resulting simulations, the mixing intensity is analyzed as a function of muscle deformation. As muscle deformation is controlled by changing the intensity of the neural signal, the material properties of the stomach wall will have a significant effect on the resultant kinematics. Thus, the model is then used to identify the source of common GI tract motility pathologies by replicating irregular motions as a consequence of varying the mechanical properties of the wall and the related activation signal patterns. This approach gives us an in-silico framework that can be used to study the effect of tissue properties & muscle activity on the mechanical response of the stomach wall. This work is supported by NIH Grant 5R01DK079902-09.

The Protein Composition of the Digestive Fluid from the Venus Flytrap Sheds Light on Prey Digestion Mechanisms*

PubMed Central

Schulze, Waltraud X.; Sanggaard, Kristian W.; Kreuzer, Ines; Knudsen, Anders D.; Bemm, Felix; Thøgersen, Ida B.; Bräutigam, Andrea; Thomsen, Line R.; Schliesky, Simon; Dyrlund, Thomas F.; Escalante-Perez, Maria; Becker, Dirk; Schultz, Jörg; Karring, Henrik; Weber, Andreas; Højrup, Peter; Hedrich, Rainer; Enghild, Jan J.

2012-01-01

The Venus flytrap (Dionaea muscipula) is one of the most well-known carnivorous plants because of its unique ability to capture small animals, usually insects or spiders, through a unique snap-trapping mechanism. The animals are subsequently killed and digested so that the plants can assimilate nutrients, as they grow in mineral-deficient soils. We deep sequenced the cDNA from Dionaea traps to obtain transcript libraries, which were used in the mass spectrometry-based identification of the proteins secreted during digestion. The identified proteins consisted of peroxidases, nucleases, phosphatases, phospholipases, a glucanase, chitinases, and proteolytic enzymes, including four cysteine proteases, two aspartic proteases, and a serine carboxypeptidase. The majority of the most abundant proteins were categorized as pathogenesis-related proteins, suggesting that the plant's digestive system evolved from defense-related processes. This in-depth characterization of a highly specialized secreted fluid from a carnivorous plant provides new information about the plant's prey digestion mechanism and the evolutionary processes driving its defense pathways and nutrient acquisition. PMID:22891002

Solute carrier transporters: potential targets for digestive system neoplasms.

PubMed

Xie, Jing; Zhu, Xiao Yan; Liu, Lu Ming; Meng, Zhi Qiang

2018-01-01

Digestive system neoplasms are the leading causes of cancer-related death all over the world. Solute carrier (SLC) superfamily is composed of a series of transporters that are ubiquitously expressed in organs and tissues of digestive systems and mediate specific uptake of small molecule substrates in facilitative manner. Given the important role of SLC proteins in maintaining normal functions of digestive system, dysregulation of these protein in digestive system neoplasms may deliver biological and clinical significance that deserves systemic studies. In this review, we critically summarized the recent advances in understanding the role of SLC proteins in digestive system neoplasms. We highlighted that several SLC subfamilies, including metal ion transporters, transporters of glucose and other sugars, transporters of urea, neurotransmitters and biogenic amines, ammonium and choline, inorganic cation/anion transporters, transporters of nucleotide, amino acid and oligopeptide organic anion transporters, transporters of vitamins and cofactors and mitochondrial carrier, may play important roles in mediating the initiation, progression, metastasis, and chemoresistance of digestive system neoplasms. Proteins in these SLC subfamilies may also have diagnostic and prognostic values to particular cancer types. Differential expression of SLC proteins in tumors of digestive system was analyzed by extracting data from human cancer database, which revealed that the roles of SLC proteins may either be dependent on the substrates they transport or be tissue specific. In addition, small molecule modulators that pharmacologically regulate the functions of SLC proteins were discussed for their possible application in the treatment of digestive system neoplasms. This review highlighted the potential of SLC family proteins as drug target for the treatment of digestive system neoplasms.

Solute carrier transporters: potential targets for digestive system neoplasms

PubMed Central

Xie, Jing; Zhu, Xiao Yan; Liu, Lu Ming; Meng, Zhi Qiang

2018-01-01

Digestive system neoplasms are the leading causes of cancer-related death all over the world. Solute carrier (SLC) superfamily is composed of a series of transporters that are ubiquitously expressed in organs and tissues of digestive systems and mediate specific uptake of small molecule substrates in facilitative manner. Given the important role of SLC proteins in maintaining normal functions of digestive system, dysregulation of these protein in digestive system neoplasms may deliver biological and clinical significance that deserves systemic studies. In this review, we critically summarized the recent advances in understanding the role of SLC proteins in digestive system neoplasms. We highlighted that several SLC subfamilies, including metal ion transporters, transporters of glucose and other sugars, transporters of urea, neurotransmitters and biogenic amines, ammonium and choline, inorganic cation/anion transporters, transporters of nucleotide, amino acid and oligopeptide organic anion transporters, transporters of vitamins and cofactors and mitochondrial carrier, may play important roles in mediating the initiation, progression, metastasis, and chemoresistance of digestive system neoplasms. Proteins in these SLC subfamilies may also have diagnostic and prognostic values to particular cancer types. Differential expression of SLC proteins in tumors of digestive system was analyzed by extracting data from human cancer database, which revealed that the roles of SLC proteins may either be dependent on the substrates they transport or be tissue specific. In addition, small molecule modulators that pharmacologically regulate the functions of SLC proteins were discussed for their possible application in the treatment of digestive system neoplasms. This review highlighted the potential of SLC family proteins as drug target for the treatment of digestive system neoplasms. PMID:29416375

Mesophilic co-digestion of dairy manure and lipid rich solid slaughterhouse wastes: process efficiency, limitations and floating granules formation.

PubMed

Pitk, Peep; Palatsi, Jordi; Kaparaju, Prasad; Fernández, Belén; Vilu, Raivo

2014-08-01

Lipid and protein rich solid slaughterhouse wastes are attractive co-substrates to increase volumetric biogas production in co-digestion with dairy manure. Addition of decanter sludge (DS), containing 42.2% of lipids and 35.8% of proteins (total solids basis), up to 5% of feed mixture resulted in a stable process without any indication of long chain fatty acids (LCFA) or free ammonia (NH3) inhibition and in 3.5-fold increase of volumetric biogas production. Contrary, only lipids addition as technical fat (TF) at over 2% of feed mixture resulted in formation of floating granules (FG) and process efficiency decrease. Formed FG had low biodegradability and its organic part was composed of lipids and calcium salts of LCFAs. Anaerobic digestion process intentionally directed to FG formation, could be a viable option for mitigation and control of lipids overload and derived LCFA inhibition. Copyright © 2014 Elsevier Ltd. All rights reserved.

Depth-resolved microbial community analyses in the anaerobic co-digester of dewatered sewage sludge with food waste.

PubMed

Xu, Rui; Yang, Zhao-Hui; Zheng, Yue; Zhang, Hai-Bo; Liu, Jian-Bo; Xiong, Wei-Ping; Zhang, Yan-Ru; Ahmad, Kito

2017-11-01

This study evaluated the impacts of FW addition on co-digestion in terms of microbial community. Anaerobic co-digestion (AcoD) reactors were conducted at gradually increased addition of food waste (FW) from 0 to 4kg-VSm -3 d -1 for 220days. Although no markable acidification was found at an OLR of 4kg-VSm -3 d -1 , the unhealthy operation was observed in aspect of an inhibited methane yield (185mLg -1 VS added ), which was restricted by 40% when compared with its peak value. Deterioration of digestion process was timely indicated by the dramatic decrease of archaeal population and microbial biodiversity. Furthermore, the cooperation network showed a considerable number of rare species (<1%) were strongly correlated with methane production, which were frequently overlooked due to the limits of detecting resolution or analysis methods before. Advances in the analysis of sensitive microbial community enable us to detect the early disturbances in AcoD reactors. Copyright © 2017 Elsevier Ltd. All rights reserved.

Digestible and indigestible carbohydrates: interactions with postprandial lipid metabolism.

PubMed

Lairon, Denis; Play, Barbara; Jourdheuil-Rahmani, Dominique

2007-04-01

The balance between fats and carbohydrates in the human diet is still a matter of very active debate. Indeed, the processing of ordinary mixed meals involves complex processes within the lumen of the upper digestive tract for digestion, in the small intestine mucosa for absorption and resecretion, and in peripheral tissues and in the circulation for final handling. The purpose of this review is to focus on available knowledge on the interactions of digestible or indigestible carbohydrates with lipid and lipoprotein metabolism in the postprandial state. The observations made in humans after test meals are reported and interpreted in the light of recent findings on the cellular and molecular levels regarding possible interplays between carbohydrates and lipid moieties in some metabolic pathways. Digestible carbohydrates, especially readily digestible starches or fructose, have been shown to exacerbate and/or delay postprandial lipemia, whereas some fiber sources can lower it. While interactions between dietary fibers and the process of lipid digestion and absorption have been studied mainly in the last decades, recent studies have shown that dietary carbohydrate moieties (e.g., glucose) can stimulate the intestinal uptake of cholesterol and lipid resecretion. In addition to the well-known glucose/fructose transporters, a number of transport proteins have recently been involved in intestinal lipid processing, whose implications in such interactions are discussed. The potential importance of postprandial insulinemia in these processes is also evaluated in the light of recent findings. The interactions of carbohydrates and lipid moieties in the postprandial state may result from both acute and chronic effects, both at transcriptional and posttranscriptional levels.

Anaerobic Digestion. Instructor's Guide. Biological Treatment Process Control.

ERIC Educational Resources Information Center

Carnegie, John W., Ed.

This instructor's guide contains materials needed to teach a four-lesson unit on anaerobic digestion control. These materials include: (1) unit overview; (2) lesson plans; (3) lecture outlines; (4) student worksheets for each lesson (with answers); and (5) two copies of a final quiz (with and without answers). Lesson 1 is a review of the theory of…

Thermophilic aerobic digestion process for producing animal nutrients and other digested products

DOE Office of Scientific and Technical Information (OSTI.GOV)

Coulthard, T.L.; Townsley, P.M.; Saben, H.S.

1981-09-29

Waste materials are digested by thermophilic bacteria to produce single-cell protein and vitamin B12. The bacteria are contained in the waste and are not inoculated. Thus, a hog manure slurry containing 10% solids was stirred with aeration in an insulated reactor to allow the temperature to be maintained at greater than 55/sup 0/. The temperature was maintained at 55-65/sup 0/ and the dissolved O/sub 2/ concentration at 1.5-3 ppm for 6 days. After 10 days reaction, the product was fed to hogs as 10% of their nutrient supply with no apparent adverse effects.

A new multiple-stage electrocoagulation process on anaerobic digestion effluent to simultaneously reclaim water and clean up biogas.

PubMed

Liu, Zhiguo; Stromberg, David; Liu, Xuming; Liao, Wei; Liu, Yan

2015-03-21

A new multiple-stage treatment process was developed via integrating electrocoagulation with biogas pumping to simultaneously reclaim anaerobic digestion effluent and clean up biogas. The 1st stage of electrocoagulation treatment under the preferred reaction condition led to removal efficiencies of 30%, 81%, 37% and >99.9% for total solids, chemical oxygen demand, total nitrogen and total phosphorus, respectively. Raw biogas was then used as a reactant and pumped into the effluent to simultaneously neutralize pH of the effluent and remove H2S in the biogas. The 2nd stage of electrocoagulation treatment on the neutralized effluent showed that under the selected reaction condition, additional 60% and 10% of turbidity and chemical oxygen demand were further removed. The study concluded a dual-purpose approach for the first time to synergistically combine biogas purification and water reclamation for anaerobic digestion system, which well addresses the downstream challenges of anaerobic digestion technology. Copyright © 2014 Elsevier B.V. All rights reserved.

Processing diets containing corn distillers' dried grains with solubles in growing broiler chickens: effects on performance, pellet quality, ileal amino acids digestibility, and intestinal microbiota.

PubMed

Kim, J S; Hosseindoust, A R; Shim, Y H; Lee, S H; Choi, Y H; Kim, M J; Oh, S M; Ham, H B; Kumar, A; Chae, B J

2018-04-03

The present study investigated the effects of feed form and distillers' dried grains with solubles (DDGS) on growth performance, nutrient digestibility, and intestine microbiota in broilers. A total of 720 broilers (Ross 308; average BW 541 ± 6 g) was randomly allotted to 6 treatments on the basis of BW. There were 6 replicates in each treatment with 20 birds per replicate. Birds were fed 3 different feed forms (mash, simple pellet, and expanded pellet) and DDGS (0 or 20% of diet) in a 3 × 2 factorial arrangement. Simple pellet (SP) and expanded pellet (EP) fed birds showed an increase in BW gain (P < 0.05). The interaction between feed processing and DDGS level was observed on pellet hardness (P < 0.01). The lowest (P < 0.01) pellet durability index (PDI) and hardness were observed in the diet with DDGS. Values for PDI and hardness were higher for EP compared with SP (P < 0.01). Simple pellet decreased ileal digestibility of CP compared to mash feed. The inclusion of DDGS decreased the digestibility of CP, and tended to decrease digestibility of DM (P = 0.056) and gross energy (P = 0.069). Expanded pellet feeding decreased (P < 0.05) the ileal digestibility of isoleucine, lysine, methionine, phenylalanine, threonine, cysteine, and glutamine compared with mash diet. Processed feed increased (P < 0.01) pH in the gizzard and duodenum; however, processing decreased pH in ileum. The addition of DDGS to the diet reduced pH in the duodenum. The population of Lactobacillus spp. was lower in the duodenum of birds fed the EP diet compared to the mash diet. Processed feed increased the colonization of Clostridium spp. in the gizzard. These results indicated that SP and EP in broiler diet had a potential to improve BW gain, but EP compromised amino acid digestibility. In addition, DDGS supplementation (20%) decreased pellet quality and CP digestibility in broiler chickens; however, the growth performance and feed intake were not affected.

Nutritional and Digestive Properties of Protein Isolates Extracted from the Muscle of the Common Carp Using pH‐Shift Processing

PubMed Central

Tian, Yuanyong; Wang, Wei; Yuan, Chunhong; Zhang, Long; Liu, Jinyang

2016-01-01

Abstract This study details the nutritional and digestive properties of protein isolates that are extracted from carp (Cyprinus Carpio L.) muscle using pH shifting methods. Alkaline (ALPI) and acid (ACPI) protein isolates exhibit higher protein yields (87.6%, 76.3%, respectively). In addition to the high recovery of myofibrillar protein, a portion of the water‐soluble proteins is also recovered. The moisture contents of ACPI and ALPI are 85.5% and 88.5%, respectively, and the crude protein contents of these two fractions are 83.20% and 83.0%, respectively, both contents of which are higher than those for fresh muscle. Most part of the ash and fat are removed in the separation process. The protein isolation is also found to be lighter and whiter than the fresh muscle and there is no difference between amino acid content of protein isolation and that of fresh muscle. The maximum solubility of water washed surimi is 73.21%, while solubility of ACPI‐2 and ALPI‐2 (pH 7.0) are 66.67% and 62.08%, respectively. The digestibility of ALPI and ACPI is improved after being treated with chymotrypsin, which is about 7–8 times as that of fresh muscle. The results indicate that the protein isolates have better nutritional and digestive properties than the fresh muscle does in food processing. Practical Applications Common carp is a lower additional value fish that exists in large amount in China. This study investigates nutritional and digestive properties of protein from carp extracted by pH shifting methods. According to the obtained data in this study, pH shifting method is a good protein recovery method that can effectively remove bone spurs, skin, fat and other impurities. In addition, sarcoplasmic proteins can also be recovered. The nutritional properties of protein isolates of carp were suitable for supplementing as an ingredient for human consumption. The pH‐shift process greatly improves the protein digestibility. Therefore, there are broad application

Sulfakinin is an important regulator of digestive processes in the migratory locust, Locusta migratoria.

PubMed

Zels, Sven; Dillen, Senne; Crabbé, Katleen; Spit, Jornt; Nachman, Ronald J; Vanden Broeck, Jozef

2015-06-01

Sulfakinin (SK) is a sulfated insect neuropeptide that is best known for its function as a satiety factor. It displays structural and functional similarities with the vertebrate peptides gastrin and cholecystokinin. Peptidomic studies in multiple insects, crustaceans and arachnids have revealed the widespread occurrence of SK in the arthropod phylum. Multiple studies in hemi- and holometabolous insects revealed the pleiotropic nature of this neuropeptide: in addition to its activity as a satiety factor, SK was also reported to affect muscle contraction, digestive enzyme release, odor preference, aggression and metabolism. However, the main site of action seems to be the digestive system of insects. In this study, we have investigated whether SK can intervene in the control of nutrient uptake and digestion in the migratory locust (Locusta migratoria). We provide evidence that sulfakinin reduces food uptake in this species. Furthermore, we discovered that SK has very pronounced effects on the main digestive enzyme secreting parts of the locust gut. It effectively reduced digestive enzyme secretion from both the midgut and gastric caeca. SK injection also elicited a reduction in absorbance and proteolytic activity of the gastric caeca contents. The characteristic sulfation of the tyrosine residue is crucial for the observed effects on digestive enzyme secretion. In an attempt to provide potential leads for the development of peptidomimetic compounds based on SK, we also tested two mimetic analogs of the natural peptide ligand in the digestive enzyme secretion assay. These analogs were able to mimic the effect of the natural SK, but their effects were milder. The results of this study provide new insights into the action of SK on the digestive system in (hemimetabolous) insects. Copyright © 2015 Elsevier Ltd. All rights reserved.

Thermophilic versus Mesophilic Anaerobic Digestion of Sewage Sludge: A Comparative Review

PubMed Central

Gebreeyessus, Getachew D.; Jenicek, Pavel

2016-01-01

During advanced biological wastewater treatment, a huge amount of sludge is produced as a by-product of the treatment process. Hence, reuse and recovery of resources and energy from the sludge is a big technological challenge. The processing of sludge produced by Wastewater Treatment Plants (WWTPs) is massive, which takes up a big part of the overall operational costs. In this regard, anaerobic digestion (AD) of sewage sludge continues to be an attractive option to produce biogas that could contribute to the wastewater management cost reduction and foster the sustainability of those WWTPs. At the same time, AD reduces sludge amounts and that again contributes to the reduction of the sludge disposal costs. However, sludge volume minimization remains, a challenge thus improvement of dewatering efficiency is an inevitable part of WWTP operation. As a result, AD parameters could have significant impact on sludge properties. One of the most important operational parameters influencing the AD process is temperature. Consequently, the thermophilic and the mesophilic modes of sludge AD are compared for their pros and cons by many researchers. However, most comparisons are more focused on biogas yield, process speed and stability. Regarding the biogas yield, thermophilic sludge AD is preferred over the mesophilic one because of its faster biochemical reaction rate. Equally important but not studied sufficiently until now was the influence of temperature on the digestate quality, which is expressed mainly by the sludge dewateringability, and the reject water quality (chemical oxygen demand, ammonia nitrogen, and pH). In the field of comparison of thermophilic and mesophilic digestion process, few and often inconclusive research, unfortunately, has been published so far. Hence, recommendations for optimized technologies have not yet been done. The review presented provides a comparison of existing sludge AD technologies and the gaps that need to be filled so as to optimize

Temperature-phased anaerobic digestion of food waste: A comparison with single-stage digestions based on performance and energy balance.

PubMed

Xiao, Benyi; Qin, Yu; Zhang, Wenzhe; Wu, Jing; Qiang, Hong; Liu, Junxin; Li, Yu-You

2018-02-01

The temperature-phased anaerobic digestion (TPAD) of food waste was studied for the purpose of comparing with single-stage mesophilic and thermophilic anaerobic digestion. The biogas and methane yields in the TPAD during the steady period were 0.759 ± 0.115 L/g added VS and 0.454 ± 0.201 L/g added VS, which were lower than those in the two single-stage anaerobic digestion. The improper sludge retention time may be the reason for the lower biogas and methane production in TPAD. The removal of volatile solids in the TPAD was 78.55 ± 4.59% and the lowest among the three anaerobic digestion processes. The reaction ratios of the four anaerobic digestion steps in the TPAD were all lower than those in the two single-stage anaerobic digestion. The energy conversion efficiency of the degraded substrate in the TPAD was similar with those in single-stage mesophilic and thermophilic anaerobic digestion systems. Copyright © 2017 Elsevier Ltd. All rights reserved.

Methanogenic pathway and community structure in a thermophilic anaerobic digestion process of organic solid waste.

PubMed

Sasaki, Daisuke; Hori, Tomoyuki; Haruta, Shin; Ueno, Yoshiyuki; Ishii, Masaharu; Igarashi, Yasuo

2011-01-01

The methanogenic pathway and microbial community in a thermophilic anaerobic digestion process of organic solid waste were investigated in a continuous-flow stirred-tank reactor using artificial garbage slurry as a feedstock. The decomposition pathway of acetate, a significant precursor of CH(4) and a key intermediate metabolite in the anaerobic digestion process, was analyzed by using stable isotopes. A tracer experiment using (13)C-labeled acetate revealed that approximately 80% of the acetate was decomposed via a non-aceticlastic oxidative pathway, whereas the remainder was converted to methane via an aceticlastic pathway. Archaeal 16S rRNA analyses demonstrated that the hydrogenotrophic methanogens Methanoculleus spp. accounted for >90% of detected methanogens, and the aceticlastic methanogens Methanosarcina spp. were the minor constituents. The clone library targeting bacterial 16S rRNA indicated the predominance of the novel Thermotogales bacterium (relative abundance: ~53%), which is related to anaerobic acetate oxidizer Thermotoga lettingae TMO, although the sequence similarity was low. Uncultured bacteria that phylogenetically belong to municipal solid waste cluster I were also predominant in the microflora (~30%). These results imply that the microbial community in the thermophilic degrading process of organic solid waste consists exclusively of unidentified bacteria, which efficiently remove acetate through a non-aceticlastic oxidative pathway. Copyright © 2010 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Microbial dynamics in anaerobic digestion reactors for treating organic urban residues during the start-up process.

PubMed

Alcántara-Hernández, R J; Taş, N; Carlos-Pinedo, S; Durán-Moreno, A; Falcón, L I

2017-06-01

Anaerobic digestion of organic residues offers economic benefits via biogas production, still methane (CH 4 ) yield relies on the development of a robust microbial consortia for adequate substrate degradation, among other factors. In this study, we monitor biogas production and changes in the microbial community composition in two semi-continuous stirred tank reactors during the setting process under mesophilic conditions (35°C) using a 16S rDNA high-throughput sequencing method. Reactors were initially inoculated with anaerobic granular sludge from a brewery wastewater treatment plant, and gradually fed organic urban residues (4·0 kg VS m -3  day -1 ) . The inocula and biomass samples showed changes related to adaptations of the community to urban organic wastes including a higher relative proportion of Clostridiales, with Ruminococcus spp. and Syntrophomonas spp. as recurrent species. Candidatus Cloacamonas spp. (Spirochaetes) also increased from ~2·2% in the inoculum to >10% in the reactor biomass. The new community consolidated the cellulose degradation and the propionate and amino acids fermentation processes. Acetoclastic methanogens were more abundant in the reactor, where Methanosaeta spp. was found as a key player. This study demonstrates a successful use of brewery treatment plant granular sludge to obtain a robust consortium for methane production from urban organic solid waste in Mexico. This study describes the selection of relevant bacteria and archaea in anaerobic digesters inoculated with anaerobic granular sludge from a brewery wastewater treatment plant. Generally, these sludge granules are used to inoculate reactors digesting organic urban wastes. Though, it is still not clearly understood how micro-organisms respond to substrate variations during the reactor start-up process. After feeding two reactors with organic urban residues, it was found that a broader potential for cellulose degradation was developed including Bacteroidetes

Digestive system fistula: a problem still relevant today.

PubMed

Głuszek, Stanisław; Korczak, Maria; Kot, Marta; Matykiewicz, Jarosław; Kozieł, Dorota

2011-01-01

Digestive system fistula originates most frequently as a complication after surgical procedures, less often occurs in the course of inflammatory diseases, but it can also result from neoplasm and injuries. THE AIM OF THE STUDY was to analyze the causes and retrospectively assess the perioperative procedures as well as the results of digestive system fistula treatment. MATERIAL AND METHODS. Own experience in digestive system fistula treatment was presented. The subject group consisted of 32 patients treated at the General Surgery, Oncology and Endocrinology Clinical Department between 01.05.2005 and 30.04.2010 due to different digestive tract diseases. The causes of the occurrence of digestive system fistula, methods and results of treatment were analyzed. RESULTS. The analysis covered 32 patients with digestive system fistula, among them 15 men and 17 women. Average age for men was 57 years (20-78), and for women 61 years (24-88). In 11 patients idiopathic fistula causally connected with primary inflammatory disease (7 cases) and with neoplasm (4 cases) was diagnosed, in 19 patients fistula was the result of complications after surgery, in 2 - after abdominal cavity injury. Recovery from fistula was achieved in 23 patients (72%) with the use of individually planned conservative therapy (TPN, EN, antibiotics, drainage, and others) and surgery, depending on the needs of individual patient. 5 patients (16%) died, whereas in 4 left (12%) recovery wasn't achieved (fistula in palliative patients, with advanced stages of neoplasm - bronchoesophageal fistula, the recurrence of uterine carcinoma). CONCLUSIONS. Recently the results of digestive system fistula treatment showed an improvement which manifests itself in mortality decrease and shortening of fistula healing time. Yet, digestive system fistula as a serious complication still poses a very difficult surgical problem.

Inactivation of selected bacterial pathogens in dairy cattle manure by mesophilic anaerobic digestion (balloon type digester).

PubMed

Manyi-Loh, Christy E; Mamphweli, Sampson N; Meyer, Edson L; Okoh, Anthony I; Makaka, Golden; Simon, Michael

2014-07-14

Anaerobic digestion of animal manure in biogas digesters has shown promise as a technology in reducing the microbial load to safe and recommended levels. We sought to treat dairy manure obtained from the Fort Hare Dairy Farm by investigating the survival rates of bacterial pathogens, through a total viable plate count method, before, during and after mesophilic anaerobic digestion. Different microbiological media were inoculated with different serial dilutions of manure samples that were withdrawn from the biogas digester at 3, 7 and 14 day intervals to determine the viable cells. Data obtained indicated that the pathogens of public health importance were 90%-99% reduced in the order: Campylobacter sp. (18 days) < Escherichia coli sp. (62 days) < Salmonella sp. (133 days) from a viable count of 10.1 × 103, 3.6 × 105, 7.4 × 103 to concentrations below the detection limit (DL = 102 cfu/g manure), respectively. This disparity in survival rates may be influenced by the inherent characteristics of these bacteria, available nutrients as well as the stages of the anaerobic digestion process. In addition, the highest p-value i.e., 0.957 for E. coli showed the statistical significance of its model and the strongest correlation between its reductions with days of digestion. In conclusion, the results demonstrated that the specific bacterial pathogens in manure can be considerably reduced through anaerobic digestion after 133 days.

Microalgal Cultivation in Treating Liquid Digestate from Biogas Systems.

PubMed

Xia, Ao; Murphy, Jerry D

2016-04-01

Biogas production via anaerobic digestion (AD) has rapidly developed in recent years. In addition to biogas, digestate is an important byproduct. Liquid digestate is the major fraction of digestate and may contain high levels of ammonia nitrogen. Traditional processing technologies (such as land application) require significant energy inputs and raise environmental risks (such as eutrophication). Alternatively, microalgae can efficiently remove the nutrients from digestate while producing high-value biomass that can be used for the production of biochemicals and biofuels. Both inorganic and organic carbon sources derived from biogas production can significantly improve microalgal production. Land requirement for microalgal cultivation is estimated as 3% of traditional direct land application of digestate. Copyright © 2015 Elsevier Ltd. All rights reserved.

Anaerobic co-digestion of pig manure and algae: impact of intracellular algal products recovery on co-digestion performance.

PubMed

Astals, S; Musenze, R S; Bai, X; Tannock, S; Tait, S; Pratt, S; Jensen, P D

2015-04-01

This paper investigates anaerobic co-digestion of pig manure and algae (Scenedesmus sp.) with and without extraction of intracellular algal co-products, with views towards the development of a biorefinery concept for lipid, protein and/or biogas production. Protein and/or lipids were extracted from Scenedesmus sp. using free nitrous acid pre-treatments and solvent-based Soxhlet extraction, respectively. Processing increased algae methane yield between 29% and 37% compared to raw algae (VS basis), but reduced the amount of algae available for digestion. Co-digestion experiments showed a synergy between pig manure and raw algae that increased raw algae methane yield from 0.163 to 0.245 m(3) CH4 kg(-1)VS. No such synergy was observed when algal residues were co-digested with pig manure. Finally, experimental results were used to develop a high-level concept for an integrated biorefinery processing pig manure and onsite cultivated algae, evaluating methane production and co-product recovery per mass of pig manure entering the refinery. Copyright © 2015 Elsevier Ltd. All rights reserved.

Digestive diseases

MedlinePlus

... this page: //medlineplus.gov/ency/article/007447.htm Digestive diseases To use the sharing features on this page, please enable JavaScript. Digestive diseases are disorders of the digestive tract, which ...

[Current concepts of digestion and absorption of carbohydrates].

PubMed

Luz, S dos S; de Campos, P L; Ribeiro, S M; Tirapegui, J

1997-01-01

The aim of this paper is to review recent aspects of digestion and absorption of carbohydrates that are the main source of energy in human diets. Recent researches have found that starch is not largely hydrolysed and absorbed in the small bowel but one part of it is resistant to digestion. Several food factors may be responsible for digestion and absorption velocity and totality of carbohydrates. Therefore, carbohydrate classification must be based not only on molecular size to express the real carbohydrates utilization as an energy source by humans. In agreement with molecular size of carbohydrate, its classification can be: a) monosaccharides; b) disaccharides; c) oligosaccharides; d) polysaccharides. In agreement with carbohydrate digestibility or availability, its classification can be: a) digestible carbohydrates; b) undigestable carbohydrates (NSP). Carbohydrate digestibility can be altered by several factors like: Intrinsic factors: a) physical structure; b) molecular physical distribution; c) physical state of food; d) food antinutrients. Extrinsics factors: a) chewing; b) transit time of food; c) amount of starch present; d) diet antinutrients. Under influence of this factors, process of digestion happen by enzymatic activity a long the gastrointestinal tract. Salivary and pancreatic amylase; glycosidases of the duodenal enterocyte brush border (lactase, sacarase and maltase), whose activity happen by close interaction of digestive breakdown with transport. The summarized pathways of the absorptive process: 1. movement from the bulk phase of the lumenal or mucosal fluid to enterocyte surface; 2. movement across the brush border membrane through specific transporters: a) SGLT1; b) GLUT 5; c) passive diffusion. 3. movement across the basolateral membrane by the GLUT 2.

Validation of an in vitro digestive system for studying macronutrient decomposition in humans.

PubMed

Kopf-Bolanz, Katrin A; Schwander, Flurina; Gijs, Martin; Vergères, Guy; Portmann, Reto; Egger, Lotti

2012-02-01

The digestive process transforms nutrients and bioactive compounds contained in food to physiologically active compounds. In vitro digestion systems have proven to be powerful tools for understanding and monitoring the complex transformation processes that take place during digestion. Moreover, the investigation of the physiological effects of certain nutrients demands an in vitro digestive process that is close to human physiology. In this study, human digestion was simulated with a 3-step in vitro process that was validated in depth by choosing pasteurized milk as an example of a complex food matrix. The evolution and decomposition of the macronutrients was followed over the entire digestive process to the level of intestinal enterocyte action, using protein and peptide analysis by SDS-PAGE, reversed-phase HPLC, size exclusion HPLC, and liquid chromatography-MS. The mean peptide size after in vitro digestion of pasteurized milk was 5-6 amino acids (AA). Interestingly, mostly essential AA (93.6%) were released during in vitro milk digestion, a significantly different relative distribution compared to the total essential AA concentration of bovine milk (44.5%). All TG were degraded to FFA and monoacylglycerols. Herein, we present a human in vitro digestion model validated for its ability to degrade the macronutrients of dairy products comparable to physiological ranges. It is suited to be used in combination with a human intestinal cell culture system, allowing ex vivo bioavailability measurements and assessment of the bioactive properties of food components.

Digestive enzyme activities in the guts of bonnethead sharks (Sphyrna tiburo) provide insight into their digestive strategy and evidence for microbial digestion in their hindguts.

PubMed

Jhaveri, Parth; Papastamatiou, Yannis P; German, Donovan P

2015-11-01

Few investigations have studied digestive enzyme activities in the alimentary tracts of sharks to gain insight into how these organisms digest their meals. In this study, we examined the activity levels of proteases, carbohydrases, and lipase in the pancreas, and along the anterior intestine, spiral intestine, and colon of the bonnethead shark, Sphyrna tiburo. We then interpreted our data in the context of a rate-yield continuum to discern this shark's digestive strategy. Our data show anticipated decreasing patterns in the activities of pancreatic enzymes moving posteriorly along the gut, but also show mid spiral intestine peaks in aminopeptidase and lipase activities, which support the spiral intestine as the main site of absorption in bonnetheads. Interestingly, we observed spikes in the activity levels of N-acetyl-β-D-glucosaminidase and β-glucosidase in the bonnethead colon, and these chitin- and cellulose-degrading enzymes, respectively, are likely of microbial origin in this distal gut region. Taken in the context of intake and relatively long transit times of food through the gut, the colonic spikes in N-acetyl-β-D-glucosaminidase and β-glucosidase activities suggest that bonnetheads take a yield-maximizing strategy to the digestive process, with some reliance on microbial digestion in their hindguts. This is one of the first studies to examine digestive enzyme activities along the gut of any shark, and importantly, the data match with previous observations that sharks take an extended time to digest their meals (consistent with a yield-maximizing digestive strategy) and that the spiral intestine is the primary site of absorption in sharks. Copyright © 2015 Elsevier Inc. All rights reserved.

Effect of digestion temperature and pH on treatment efficiency and evolution of volatile fatty acids during thermophilic aerobic digestion of model high strength agricultural waste.

PubMed

Ugwuanyi, J Obeta; Harvey, L M; McNeil, B

2005-04-01

Thermophilic aerobic digestion (TAD) of a model agricultural waste, potato peel slurry, at soluble chemical oxygen demand (COD) load equivalent to approximately 8.0 gl(-1), was carried out under batch conditions at 0.5 vvm aeration rate. Digestions were carried out at temperatures of 45, 50, 55, 60 and 65 degrees C (or left unregulated) without pH control to study the effect of digestion temperatures on TAD. The effects of digestion pH on the process were studied at pH 6.0, 7.0, 8.0, 9.0 and 9.5 (and in unregulated control) all at 55 degrees C. Except for digestion at 65 degrees C, which was inoculated extraneously using culture of Bacillus strearothermophilus all reactions were carried out using the populations indigenous to the waste. During digestion at different temperatures, the removal of soluble COD increased with temperature to reach a peak at 60 degrees C before declining slightly, removal of soluble solid (SS) followed similar pattern and reached peak at 65 degrees C being the highest temperature studied, while the degradation of TSS and TS (TSS + TS) decreased with an increase in temperature. Digestion at pH 7.0 was more efficient than at other pH values. Acetate was the predominant volatile fatty acid (VFA) in all the reactions and accounted for up to 90% of the total. Digestion at 60 degrees C led to the greatest accumulation of acetate, and this coincided with the period of highest oxygen uptake, and rapid consumption of soluble carbohydrate. Iso-valerate was also produced at all pH values. Digestion at 55 degrees C and also at pH 7.0 led to rapid and efficient processes with least accumulation of VFA and should be of interest in full-scale processes whenever it is practicable to regulate the digestion pH and temperature. The result of digestion at unregulated pH indicates that gradual adaptation may be used to achieve efficient treatment at elevated pH values. This would be of interest in full-scale processes where it is not practicable to tightly

Advanced Antenna Measurement Processing

DTIC Science & Technology

2014-06-18

reflector antenna where the reflector functions as a passive scatterer. Here we proposed to demonstrate this separation scheme using experimentally derived...orders in the multiple reflections between these antennas . The nature of these composite patterns is not known a priori so one cannot know the accuracy...SECURITY CLASSIFICATION OF: This research project is focused on the advancement of methods of post measurement processing of antenna pattern

Less is More: Membrane Protein Digestion Beyond Urea-Trypsin Solution for Next-level Proteomics.

PubMed

Zhang, Xi

2015-09-01

The goal of next-level bottom-up membrane proteomics is protein function investigation, via high-coverage high-throughput peptide-centric quantitation of expression, modifications and dynamic structures at systems scale. Yet efficient digestion of mammalian membrane proteins presents a daunting barrier, and prevalent day-long urea-trypsin in-solution digestion proved insufficient to reach this goal. Many efforts contributed incremental advances over past years, but involved protein denaturation that disconnected measurement from functional states. Beyond denaturation, the recent discovery of structure/proteomics omni-compatible detergent n-dodecyl-β-d-maltopyranoside, combined with pepsin and PNGase F columns, enabled breakthroughs in membrane protein digestion: a 2010 DDM-low-TCEP (DLT) method for H/D-exchange (HDX) using human G protein-coupled receptor, and a 2015 flow/detergent-facilitated protease and de-PTM digestions (FDD) for integrative deep sequencing and quantitation using full-length human ion channel complex. Distinguishing protein solubilization from denaturation, protease digestion reliability from theoretical specificity, and reduction from alkylation, these methods shifted day(s)-long paradigms into minutes, and afforded fully automatable (HDX)-protein-peptide-(tandem mass tag)-HPLC pipelines to instantly measure functional proteins at deep coverage, high peptide reproducibility, low artifacts and minimal leakage. Promoting-not destroying-structures and activities harnessed membrane proteins for the next-level streamlined functional proteomics. This review analyzes recent advances in membrane protein digestion methods and highlights critical discoveries for future proteomics. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

Less is More: Membrane Protein Digestion Beyond Urea–Trypsin Solution for Next-level Proteomics*

PubMed Central

Zhang, Xi

2015-01-01

The goal of next-level bottom-up membrane proteomics is protein function investigation, via high-coverage high-throughput peptide-centric quantitation of expression, modifications and dynamic structures at systems scale. Yet efficient digestion of mammalian membrane proteins presents a daunting barrier, and prevalent day-long urea–trypsin in-solution digestion proved insufficient to reach this goal. Many efforts contributed incremental advances over past years, but involved protein denaturation that disconnected measurement from functional states. Beyond denaturation, the recent discovery of structure/proteomics omni-compatible detergent n-dodecyl-β-d-maltopyranoside, combined with pepsin and PNGase F columns, enabled breakthroughs in membrane protein digestion: a 2010 DDM-low-TCEP (DLT) method for H/D-exchange (HDX) using human G protein-coupled receptor, and a 2015 flow/detergent-facilitated protease and de-PTM digestions (FDD) for integrative deep sequencing and quantitation using full-length human ion channel complex. Distinguishing protein solubilization from denaturation, protease digestion reliability from theoretical specificity, and reduction from alkylation, these methods shifted day(s)-long paradigms into minutes, and afforded fully automatable (HDX)-protein-peptide-(tandem mass tag)-HPLC pipelines to instantly measure functional proteins at deep coverage, high peptide reproducibility, low artifacts and minimal leakage. Promoting—not destroying—structures and activities harnessed membrane proteins for the next-level streamlined functional proteomics. This review analyzes recent advances in membrane protein digestion methods and highlights critical discoveries for future proteomics. PMID:26081834

[Nursing process in advanced cardiopulmonary resuscitation].

PubMed

Lucio Peña, Gerardo; Fuentes Leonardo, Ana María

2002-01-01

The process male nurse is a systematic and organized method to offer effective and efficient cares guided to the achievement of solving real problems of health, reducing the incidence and the duration. It is organized and systematic for that consists of five sequential and interrelated steps: Valuation, diagnostic, planning, execution and evaluation, in which are carried out interrelated actions, thought to maximize the long term results. The nurse process is based on the notion that the success of the cares is measured by the degree of effectiveness and the degree of satisfaction and the patient's progress. Applying this method in the Advanced Cardiac Live Support (ACLS) the identification of a cardiovascular or cardiopulmonary urgency was achieved that implies advanced treatment of the air road, defibrillation and appropriate medications to the circumstances. The ACLS challenges the nurses in charge from the patient's attention to make decisions quick low pressure and in dramatic scenes. Reason why it develops the flowing process male nurse in the advanced cardiopulmonary reanimation due to the incidence of these events in the National Institute of Cardiology Ignacio Chávez, which should guarantee the benefit of services in basic and advanced cardiopulmonary reanimation for personal with a high formation level in all the units of intensive cares and services of hospitalization in integrated form and stratified this way to avoid that it progresses to situations that cause the death or leave irreversible sequels since in the central nervous system the time it is a factor critical for the treatment of this events.

Starch Origin and Thermal Processing Affect Starch Digestion in a Minipig Model of Pancreatic Exocrine Insufficiency.

PubMed

Mößeler, Anne; Vagt, Sandra; Beyerbach, Martin; Kamphues, Josef

2015-01-01

Although steatorrhea is the most obvious symptom of pancreatic exocrine insufficiency (PEI), enzymatic digestion of protein and starch is also impaired. Low praecaecal digestibility of starch causes a forced microbial fermentation accounting for energy losses and meteorism. To optimise dietetic measures, knowledge of praecaecal digestibility of starch is needed but such information from PEI patients is rare. Minipigs fitted with an ileocaecal fistula with (n = 3) or without (n = 3) pancreatic duct ligation (PL) were used to estimate the rate of praecaecal disappearance (pcD) of starch. Different botanical sources of starch (rice, amaranth, potato, and pea) were fed either raw or cooked. In the controls (C), there was an almost complete pcD (>92%) except for potato starch (61.5%) which was significantly lower. In PL pcD of raw starch was significantly lower for all sources of starch except for amaranth (87.9%). Thermal processing increased pcD in PL, reaching values of C for starch from rice, potato, and pea. This study clearly underlines the need for precise specification of starch used for patients with specific dietetic needs like PEI. Data should be generated in suitable animal models or patients as tests in healthy individuals would not have given similar conclusions.

Micro-quantity tissue digestion for metal measurements by use of a microwave acid-digestion bomb.

PubMed

Nicholson, J R; Savory, M G; Savory, J; Wills, M R

1989-03-01

We describe a simple and convenient method for processing small amounts of tissue samples for trace-metal measurements by atomic absorption spectrometry, by use of a modified Parr microwave digestion bomb. Digestion proceeds rapidly (less than or equal to 90 s) in a sealed Teflon-lined vessel that eliminates contamination or loss from volatilization. Small quantities of tissue (5-100 mg dry weight) are digested in high-purity nitric acid, yielding concentrations of analyte that can be measured directly without further sample manipulation. We analyzed National Institute of Standards and Technology bovine liver Standard Reference Material to verify the accuracy of the technique. We assessed the applicability of the technique to analysis for aluminum in bone by comparison with a dry ashing procedure.

Digestion of starch in a dynamic small intestinal model.

PubMed

Jaime-Fonseca, M R; Gouseti, O; Fryer, P J; Wickham, M S J; Bakalis, S

2016-12-01

The rate and extent of starch digestion have been linked with important health aspects, such as control of obesity and type-2 diabetes. In vitro techniques are often used to study digestion and simulated nutrient absorption; however, the effect of gut motility is often disregarded. The present work aims at studying fundamentals of starch digestion, e.g. the effect of viscosity on digestibility, taking into account both biochemical and engineering (gut motility) parameters. New small intestinal model (SIM) that realistically mimics gut motility (segmentation) was used to study digestibility and simulated oligosaccharide bio accessibility of (a) model starch solutions; (b) bread formulations. First, the model was compared with the rigorously mixed stirred tank reactor (STR). Then the effects of enzyme concentration/flow rate, starch concentration, and digesta viscosity (addition of guar gum) were evaluated. Compared to the STR, the SIM showed presence of lag phase when no digestive processes could be detected. The effects of enzyme concentration and flow rate appeared to be marginal in the region of mass transfer limited reactions. Addition of guar gum reduced simulated glucose absorption by up to 45 % in model starch solutions and by 35 % in bread formulations, indicating the importance of chyme rheology on nutrient bioaccessibility. Overall, the work highlights the significance of gut motility in digestive processes and offers a powerful tool in nutritional studies that, additionally to biochemical, considers engineering aspects of digestion. The potential to modulate food digestibility and nutrient bioaccessibility by altering food formulation is indicated.

Effect of four processed animal proteins in the diet on digestibility and performance in laying hens.

PubMed

van Krimpen, M M; Veldkamp, T; Binnendijk, G P; de Veer, R

2010-12-01

An experiment was performed to investigate the effect of animal vs. vegetable protein sources in the diet of laying hens on the development of hen performance. A diet containing protein sources of only vegetable origin was compared with 4 diets, each containing 1 of 4 processed animal proteins (PAP). Two PAP (Daka-58 and Sonac-60) were classified as meat meals, and the remaining 2 (Daka-40 and Sonac-50) were classified as meat and bone meals. First, fecal digestibility of nutrients in the PAP was determined in Lohmann Brown layers. Hens (n = 132) were housed in 22 cages (6 hens/cage) and allotted to 5 dietary treatments. In the PAP diets (4 replicates/treatment), 100 g/kg of CP of animal origin was added, replacing soybean meal and corn (Zea mays) in the basal diet (6 replicates/treatment). The PAP sources differed largely in chemical composition and digestibility coefficients. Energy content (AME(n)) varied from 1,817 (Daka-40) to 3,107 kcal/kg (Sonac-60), and digestible lysine varied from 15.4 (Daka-40) to 28.3 g/kg (Sonac-50). Subsequently, the effect of a control diet (without PAP) vs. 4 PAP diets (50 g/kg of CP of animal origin from the same batches as used in the digestibility study) on performance was determined. All diets were isocaloric (AME(n) = 2,825 kcal/kg) and isonitrogenous (digestible lysine = 6.8 g/kg). Hens were housed in 40 floor pens (12 hens/pen, 8 pens/treatment) from 20 to 40 wk of age. Feed intake levels of the hens fed the meat and bone meal diets were reduced compared with those of hens fed the meat meal diets, whereas the feed intake level of hens fed the control diet was intermediate. Laying hen performance differed between treatments, being was most favorable for the Sonac-50 treatment and most adverse for the Daka-40 treatment. Differences in laying hen performance seemed to be related partly to differences in feed intake and corresponding amino acid intake.

Inactivation of Selected Bacterial Pathogens in Dairy Cattle Manure by Mesophilic Anaerobic Digestion (Balloon Type Digester)

PubMed Central

Manyi-Loh, Christy E.; Mamphweli, Sampson N.; Meyer, Edson L.; Okoh, Anthony I.; Makaka, Golden; Simon, Michael

2014-01-01

Anaerobic digestion of animal manure in biogas digesters has shown promise as a technology in reducing the microbial load to safe and recommended levels. We sought to treat dairy manure obtained from the Fort Hare Dairy Farm by investigating the survival rates of bacterial pathogens, through a total viable plate count method, before, during and after mesophilic anaerobic digestion. Different microbiological media were inoculated with different serial dilutions of manure samples that were withdrawn from the biogas digester at 3, 7 and 14 day intervals to determine the viable cells. Data obtained indicated that the pathogens of public health importance were 90%–99% reduced in the order: Campylobacter sp. (18 days) < Escherichia coli sp. (62 days) < Salmonella sp. (133 days) from a viable count of 10.1 × 103, 3.6 × 105, 7.4 × 103 to concentrations below the detection limit (DL = 102 cfu/g manure), respectively. This disparity in survival rates may be influenced by the inherent characteristics of these bacteria, available nutrients as well as the stages of the anaerobic digestion process. In addition, the highest p-value i.e., 0.957 for E. coli showed the statistical significance of its model and the strongest correlation between its reductions with days of digestion. In conclusion, the results demonstrated that the specific bacterial pathogens in manure can be considerably reduced through anaerobic digestion after 133 days. PMID:25026086

The In Vitro Effects of Enzymatic Digested Gliadin on the Functionality of the Autophagy Process

PubMed Central

Manai, Federico; Azzalin, Alberto; Gabriele, Fabio; Martinelli, Carolina; Morandi, Martina; Comincini, Sergio

2018-01-01

Gliadin, the alcohol-soluble protein fraction of wheat, contains the factor toxic for celiac disease (CD), and its toxicity is not reduced by digestion with gastro-pancreatic enzymes. Importantly, it is proved that an innate immunity to gliadin plays a key role in the development of CD. The immune response induces epithelial stress and reprograms intraepithelial lymphocytes into natural killer (NK)-like cells, leading to enterocyte apoptosis and an increase in epithelium permeability. In this contribution, we have reported that in Caco-2 cells the administration of enzymatically digested gliadin (PT-gliadin) reduced significantly the expression of the autophagy-related marker LC3-II. Furthermore, electron and fluorescent microscope analysis suggested a compromised functionality of the autophagosome apparatus. The rescue of the dysregulated autophagy process, along with a reduction of PT-gliadin toxicity, was obtained with a starvation induction protocol and by 3-methyladenine administration, while rapamycin, a well-known autophagy inducer, did not produce a significant improvement in the clearance of extra- and intra-cellular fluorescent PT-gliadin amount. Altogether, our results highlighted the possible contribution of the autophagy process in the degradation and in the reduction of extra-cellular release of gliadin peptides and suggest novel molecular targets to counteract gliadin-induced toxicity in CD. PMID:29473905

Evaluation of hydrogen and methane production from sugarcane bagasse hemicellulose hydrolysates by two-stage anaerobic digestion process.

PubMed

Baêta, Bruno Eduardo Lobo; Lima, Diego Roberto Sousa; Filho, José Gabriel Balena; Adarme, Oscar Fernando Herrera; Gurgel, Leandro Vinícius Alves; Aquino, Sérgio Francisco de

2016-10-01

This study aimed at optimizing the net energy recovery from hydrogen and methane production through anaerobic digestion of the hemicellulose hydrolysate (HH) obtained by desirable conditions (DC) of autohydrolysis pretreatment (AH) of sugarcane bagasse (SB). Anaerobic digestion was carried out in a two-stage (acidogenic-methanogenic) batch system where the acidogenic phase worked as a hydrolysis and biodetoxification step. This allowed the utilization of more severe AH pretreatment conditions, i.e. T=178.6°C and t=55min (DC3) and T=182.9°C and t=40.71min (DC4). Such severe conditions resulted in higher extraction of hemicelluloses from SB (DC1=68.07%, DC2=48.99%, DC3=77.40% and DC4=73.90%), which consequently improved the net energy balance of the proposed process. The estimated energy from the combustion of both biogases (H2 and CH4) accumulated during the two-stage anaerobic digestion of HH generated by DC4 condition was capable of producing a net energy of 3.15MJ·kgSB(-1)dry weight. Copyright © 2016 Elsevier Ltd. All rights reserved.

Motivating Low Performing Adolescent Readers. ERIC Digest.

ERIC Educational Resources Information Center

Collins, Norma Decker

This Digest focuses on motivating the low performing adolescent in a remedial reading or subject area classroom--the idea is that students who are disengaged from their own learning processes are not likely to perform well in school. The Digest points out that such adolescents are often caught in a cycle of failure and that secondary teachers must…

Low temperature vapor phase digestion of graphite

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pierce, Robert A.

2017-04-18

A method for digestion and gasification of graphite for removal from an underlying surface is described. The method can be utilized to remove graphite remnants of a formation process from the formed metal piece in a cleaning process. The method can be particularly beneficial in cleaning castings formed with graphite molding materials. The method can utilize vaporous nitric acid (HNO.sub.3) or vaporous HNO.sub.3 with air/oxygen to digest the graphite at conditions that can avoid damage to the underlying surface.

The Media's Role in Political Campaigns. ERIC Digest.

ERIC Educational Resources Information Center

Gottlieb, Stephen S.

This digest examines the relationship between the political process and the media. The digest discusses the ramifications of advertising in politics; the role of the televised debate in elections; individual voter characteristics and the media; and media coverage and campaign awareness. Fifteen references are attached. (RS)

Enhancement of anaerobic digestion efficiency of wastewater sludge and olive waste: Synergistic effect of co-digestion and ultrasonic/microwave sludge pre-treatment.

PubMed

Alagöz, B Aylin; Yenigün, Orhan; Erdinçler, Ayşen

2015-12-01

This study investigates the effect of ultrasonic and microwave pre-treatment on biogas production from the anaerobic co-digestion of olive pomace and wastewater sludges. It was found that co-digestion of wastewater sludge with olive pomace yielded around 0.21 L CH4/g VS added, whereas the maximum methane yields from the mono-digestion of olive pomace and un-pretreated wastewater sludges were 0.18 and 0.16L CH4/g VS added. In the same way, compared to mono-digestion of these substrates, co-digestion increased methane production by 17-31%. The microwave and ultrasonic pre-treatments applied to sludge samples prior to co-digestion process led to further increase in the methane production by 52% and 24%, respectively, compared to co-digestion with un-pretreated wastewater sludge. The highest biogas and methane yields were obtained from the co-digestion of 30 min microwave pre-treated wastewater sludges and olive pomace to be 0.46 L/g VS added and 0.32 L CH4/g VS added, respectively. Copyright © 2015 Elsevier Ltd. All rights reserved.

Advances in natural language processing.

PubMed

Hirschberg, Julia; Manning, Christopher D

2015-07-17

Natural language processing employs computational techniques for the purpose of learning, understanding, and producing human language content. Early computational approaches to language research focused on automating the analysis of the linguistic structure of language and developing basic technologies such as machine translation, speech recognition, and speech synthesis. Today's researchers refine and make use of such tools in real-world applications, creating spoken dialogue systems and speech-to-speech translation engines, mining social media for information about health or finance, and identifying sentiment and emotion toward products and services. We describe successes and challenges in this rapidly advancing area. Copyright © 2015, American Association for the Advancement of Science.

40 CFR 428.80 - Applicability; description of the wet digestion reclaimed rubber subcategory.

Code of Federal Regulations, 2010 CFR

2010-07-01

... digestion reclaimed rubber subcategory. 428.80 Section 428.80 Protection of Environment ENVIRONMENTAL... Wet Digestion Reclaimed Rubber Subcategory § 428.80 Applicability; description of the wet digestion... discharges resulting from the production of reclaimed rubber by use of the wet digestion process. ...

40 CFR 428.80 - Applicability; description of the wet digestion reclaimed rubber subcategory.

Code of Federal Regulations, 2011 CFR

2011-07-01

... digestion reclaimed rubber subcategory. 428.80 Section 428.80 Protection of Environment ENVIRONMENTAL... Wet Digestion Reclaimed Rubber Subcategory § 428.80 Applicability; description of the wet digestion... discharges resulting from the production of reclaimed rubber by use of the wet digestion process. ...

Comparative Digestive Physiology

PubMed Central

Karasov, William H.; Douglas, Angela E.

2015-01-01

In vertebrates and invertebrates, morphological and functional features of gastrointestinal (GI) tracts generally reflect food chemistry, such as content of carbohydrates, proteins, fats, and material(s) refractory to rapid digestion (e.g., cellulose). The expression of digestive enzymes and nutrient transporters approximately matches the dietary load of their respective substrates, with relatively modest excess capacity. Mechanisms explaining differences in hydrolase activity between populations and species include gene copy number variations and single-nucleotide polymorphisms. Transcriptional and posttranscriptional adjustments mediate phenotypic changes in the expression of hydrolases and transporters in response to dietary signals. Many species respond to higher food intake by flexibly increasing digestive compartment size. Fermentative processes by symbiotic microorganisms are important for cellulose degradation but are relatively slow, so animals that rely on those processes typically possess special enlarged compartment(s) to maintain a microbiota and other GI structures that slow digesta flow. The taxon richness of the gut microbiota, usually identified by 16S rRNA gene sequencing, is typically an order of magnitude greater in vertebrates than invertebrates, and the interspecific variation in microbial composition is strongly influenced by diet. Many of the nutrient transporters are orthologous across different animal phyla, though functional details may vary (e.g., glucose and amino acid transport with K+ rather than Na+ as a counter ion). Paracellular absorption is important in many birds. Natural toxins are ubiquitous in foods and may influence key features such as digesta transit, enzymatic breakdown, microbial fermentation, and absorption PMID:23720328

Biochemical, Transcriptomic and Proteomic Analyses of Digestion in the Scorpion Tityus serrulatus: Insights into Function and Evolution of Digestion in an Ancient Arthropod

PubMed Central

Fuzita, Felipe J.; Pinkse, Martijn W. H.; Patane, José S. L.; Juliano, Maria A.; Verhaert, Peter D. E. M.; Lopes, Adriana R.

2015-01-01

Scorpions are among the oldest terrestrial arthropods and they have passed through small morphological changes during their evolutionary history on land. They are efficient predators capable of capturing and consuming large preys and due to envenomation these animals can become a human health challenge. Understanding the physiology of scorpions can not only lead to evolutionary insights but also is a crucial step in the development of control strategies. However, the digestive process in scorpions has been scarcely studied. In this work, we describe the combinatory use of next generation sequencing, proteomic analysis and biochemical assays in order to investigate the digestive process in the yellow scorpion Tityus serrulatus, mainly focusing in the initial protein digestion. The transcriptome generated database allowed the quantitative identification by mass spectrometry of different enzymes and proteins involved in digestion. All the results suggested that cysteine cathepsins play an important role in protein digestion. Two digestive cysteine cathepsins were isolated and characterized presenting acidic characteristics (pH optima and stability), zymogen conversion to the mature form after acidic activation and a cross-class inhibition by pepstatin. A more elucidative picture of the molecular mechanism of digestion in a scorpion was proposed based on our results from Tityus serrulatus. The midgut and midgut glands (MMG) are composed by secretory and digestive cells. In fasting animals, the secretory granules are ready for the next predation event, containing enzymes needed for alkaline extra-oral digestion which will compose the digestive fluid, such as trypsins, astacins and chitinase. The digestive vacuoles are filled with an acidic proteolytic cocktail to the intracellular digestion composed by cathepsins L, B, F, D and legumain. Other proteins as lipases, carbohydrases, ctenitoxins and a chitolectin with a perithrophin domain were also detected. Evolutionarily

Biochemical, transcriptomic and proteomic analyses of digestion in the scorpion Tityus serrulatus: insights into function and evolution of digestion in an ancient arthropod.

PubMed

Fuzita, Felipe J; Pinkse, Martijn W H; Patane, José S L; Juliano, Maria A; Verhaert, Peter D E M; Lopes, Adriana R

2015-01-01

Scorpions are among the oldest terrestrial arthropods and they have passed through small morphological changes during their evolutionary history on land. They are efficient predators capable of capturing and consuming large preys and due to envenomation these animals can become a human health challenge. Understanding the physiology of scorpions can not only lead to evolutionary insights but also is a crucial step in the development of control strategies. However, the digestive process in scorpions has been scarcely studied. In this work, we describe the combinatory use of next generation sequencing, proteomic analysis and biochemical assays in order to investigate the digestive process in the yellow scorpion Tityus serrulatus, mainly focusing in the initial protein digestion. The transcriptome generated database allowed the quantitative identification by mass spectrometry of different enzymes and proteins involved in digestion. All the results suggested that cysteine cathepsins play an important role in protein digestion. Two digestive cysteine cathepsins were isolated and characterized presenting acidic characteristics (pH optima and stability), zymogen conversion to the mature form after acidic activation and a cross-class inhibition by pepstatin. A more elucidative picture of the molecular mechanism of digestion in a scorpion was proposed based on our results from Tityus serrulatus. The midgut and midgut glands (MMG) are composed by secretory and digestive cells. In fasting animals, the secretory granules are ready for the next predation event, containing enzymes needed for alkaline extra-oral digestion which will compose the digestive fluid, such as trypsins, astacins and chitinase. The digestive vacuoles are filled with an acidic proteolytic cocktail to the intracellular digestion composed by cathepsins L, B, F, D and legumain. Other proteins as lipases, carbohydrases, ctenitoxins and a chitolectin with a perithrophin domain were also detected. Evolutionarily

Semi-continuous anaerobic co-digestion of cow manure and steam-exploded Salix with recirculation of liquid digestate.

PubMed

Estevez, Maria M; Sapci, Zehra; Linjordet, Roar; Schnürer, Anna; Morken, John

2014-04-01

The effects of recirculating the liquid fraction of the digestate during mesophilic anaerobic co-digestion of steam-exploded Salix and cow manure were investigated in laboratory-scale continuously stirred tank reactors. An average organic loading rate of 2.6 g VS L(-1) d(-1) and a hydraulic retention time (HRT) of 30 days were employed. Co-digestion of Salix and manure gave better methane yields than digestion of manure alone. Also, a 16% increase in the methane yield was achieved when digestate was recirculated and used instead of water to dilute the feedstock (1:1 dilution ratio). The reactor in which the larger fraction of digestate was recirculated (1:3 dilution ratio) gave the highest methane yields. Ammonia and volatile fatty acids did not reach inhibitory levels, and some potentially inhibitory compounds released during steam explosion (i.e., furfural and 5-hydroxy methyl furfural) were only detected at trace levels throughout the entire study period. However, accumulation of solids, which was more pronounced in the recycling reactors, led to decreased methane yields in those systems after three HRTs. Refraining from the use of fresh water to dilute biomass with a high-solids content and obtaining a final digestate with increased dry matter content might offer important economic benefits in full-scale processes. To ensure long-term stability in such an approach, it would be necessary to optimize separation of the fraction of digestate to be recirculated and also perform proper monitoring to avoid accumulation of solids. Copyright © 2014 Elsevier Ltd. All rights reserved.

Effect of oil content and kernel processing of corn silage on digestibility and milk production by dairy cows.

PubMed

Weiss, W P; Wyatt, D J

2000-02-01

Corn silages were produced from a high oil corn hybrid and from its conventional hybrid counterpart and were harvested with a standard silage chopper or a chopper equipped with a kernel processing unit. High oil silages had higher concentrations of fatty acids (5.5 vs. 3.4% of dry matter) and crude protein (8.4 vs. 7.5% of dry matter) than the conventional hybrid. Processed silage had larger particle size than unprocessed silage, but more starch was found in small particles for processed silage. Dry matter intake was not influenced by treatment (18.4 kg/d), but yield of fat-corrected milk (23.9 vs. 22.6 kg/d) was increased by feeding high oil silage. Overall, processing corn silage did not affect milk production, but cows fed processed conventional silage tended to produce more milk than did cows fed unprocessed conventional silage. Milk protein percent, but not yield, was reduced with high oil silage. Milk fat percent, but not yield, was higher with processed silage. Overall, processed silage had higher starch digestibility, but the response was much greater for the conventional silage hybrid. The concentration of total digestible nutrients (TDN) tended to be higher for diets with high oil silage (71.6 vs. 69.9%) and tended to be higher for processed silage than unprocessed silage (71.7 vs. 69.8%), but an interaction between variety and processing was observed. Processing conventional corn silage increased TDN to values similar to high oil corn silage but processing high oil corn silage did not influence TDN.

Aerobic sludge digestion under low dissolved oxygen concentrations.

PubMed

Arunachalam, RaviSankar; Shah, Hemant K; Ju, Lu-Kwang

2004-01-01

negative effect on digestion kinetics. The use of multistage digesters, especially with small front-end reactors, may be advantageous in both "process" kinetics and "biological reaction" kinetics for sludge digestion.

Activated zeolite--suitable carriers for microorganisms in anaerobic digestion processes?

PubMed

Weiß, S; Lebuhn, M; Andrade, D; Zankel, A; Cardinale, M; Birner-Gruenberger, R; Somitsch, W; Ueberbacher, B J; Guebitz, G M

2013-04-01

Plant cell wall structures represent a barrier in the biodegradation process to produce biogas for combustion and energy production. Consequently, approaches concerning a more efficient de-polymerisation of cellulose and hemicellulose to monomeric sugars are required. Here, we show that natural activated zeolites (i.e. trace metal activated zeolites) represent eminently suitable mineral microhabitats and potential carriers for immobilisation of microorganisms responsible for anaerobic hydrolysis of biopolymers stabilising related bacterial and methanogenic communities. A strategy for comprehensive analysis of immobilised anaerobic populations was developed that includes the visualisation of biofilm formation via scanning electron microscopy and confocal laser scanning microscopy, community and fingerprint analysis as well as enzyme activity and identification analyses. Using SDS polyacrylamide gel electrophoresis, hydrolytical active protein bands were traced by congo red staining. Liquid chromatography/mass spectroscopy revealed cellulolytical endo- and exoglucanase (exocellobiohydrolase) as well as hemicellulolytical xylanase/mannase after proteolytic digestion. Relations to hydrolytic/fermentative zeolite colonisers were obtained by using single-strand conformation polymorphism analysis (SSCP) based on amplification of bacterial and archaeal 16S rRNA fragments. Thereby, dominant colonisers were affiliated to the genera Clostridium, Pseudomonas and Methanoculleus. The specific immobilisation on natural zeolites with functional microbes already colonising naturally during the fermentation offers a strategy to systematically supply the biogas formation process responsive to population dynamics and process requirements.

New perspectives for Advanced Oxidation Processes.

PubMed

Dewil, Raf; Mantzavinos, Dionissios; Poulios, Ioannis; Rodrigo, Manuel A

2017-06-15

Advanced Oxidation Processes (AOPs) are called to fill the gap between the treatability attained by conventional physico-chemical and biological treatments and the day-to-day more exigent limits fixed by environmental regulations. They are particularly important for the removal of anthropogenic pollutants and for this reason, they have been widely investigated in the last decades and even applied in the treatment of many industrial wastewater flows. However, despite the great development reached, AOPs cannot be considered mature yet and there are many new fields worthy of research. Some of them are going to be briefly introduced in this paper, including hybrid processes, heterogeneous semiconductor photocatalysis, sulphate-radical oxidation and electrochemical advanced oxidation for water/wastewater treatment. Moreover, the use of photoelectrochemical processes for energy production is discussed. The work ends with some perspectives that can be of interest for the ongoing and future research. Copyright © 2017. Published by Elsevier Ltd.

In vitro digestibility, protein composition and techno-functional properties of Saskatchewan grown yellow field peas (Pisum sativum L.) as affected by processing.

PubMed

Ma, Zhen; Boye, Joyce I; Hu, Xinzhong

2017-02-01

Saskatchewan grown yellow field pea was subjected to different processing conditions including dehulling, micronization, roasting, conventional/microwave cooking, germination, and combined germination and conventional cooking/roasting. Their nutritional and antinutritional compositions, functional properties, microstructure, thermal properties, in vitro protein and starch digestibility, and protein composition were studied. Processed field peas including conventional cooked yellow peas (CCYP), microwave cooked yellow peas (MCYP), germinated-conventional cooked yellow peas (GCCYP), and germinated-roasted yellow peas (GRYP) exhibited the significantly higher in vitro protein digestibility (IVPD), which was in accordance with their significantly lower trypsin inhibitor activity and tannin content. The SDS-PAGE and size exclusion HPLC profiles of untreated pea proteins and their hydrolysates also confirmed the IVPD result that these four treatments facilitated the hydrolysis of pea proteins to a greater extent. The CCYP, MCYP, GCCYP, and GRYP also exhibited significantly higher starch digestibility which was supported by their lower onset (T o ), peak (T p ), and conclusion (T c ) temperatures obtained from DSC thermogram, their lower pasting properties and starch damage results, as well as their distinguished amorphous flakes' configuration observed on the scanning electron microscopic image. LC/ESI-MS/MS analysis following in-gel digests of SDS-PAGE separated proteins allowed detailed compositional characterization of pea proteins. The present study would provide fundamental information to help to better understand the functionality of field peas as ingredients, and particularly in regards to agri-food industry to improve the process efficiency of field peas with enhanced nutritional and techno-functional qualities. Copyright © 2016 Elsevier Ltd. All rights reserved.

Survival rates of parasite eggs in sludge during aerobic and anaerobic digestion.

PubMed Central

Black, M I; Scarpino, P V; O'Donnell, C J; Meyer, K B; Jones, J V; Kaneshiro, E S

1982-01-01

The effects of mesothermic anaerobic or aerobic sludge digestion on survival of eggs from the roundworms Ascaris suum, toxocara canis, Trichuris vulpis, and Trichuris suis and from the rat tapeworm Hymenolepis diminuta were studied. Destruction of eggs throughout a 15-day treatment period, as well as their viabilities after reisolation, was analyzed. The laboratory model digesters used in this study were maintained at a 15-day retention schedule, partially simulating a continuously operating system. Ascaris eggs were destroyed in the anaerobic (23%) or aerobic (38%) digesters, and 11% Trichuris eggs were destroyed in the aerobic digesters. Trichuris eggs in anaerobic digesters and Toxocara eggs in either anaerobic or aerobic digesters were not destroyed. Destruction of eggs in digesters was correlated with the state of the eggs before subjection to the treatment processes; i.e., some Ascaris and Trichuris eggs were already embryonated in host intestinal contents or feces and hence past their most resistant stage. The viabilities of Ascaris and Toxocara eggs that survived the digestion processes were greater in anaerobically treated than in aerobically treated material. Eggs from Hymenolepis were nonviable before use in the experiments. However, they were more effectively destroyed in aerobic digesters than in anaerobic digesters. PMID:6891199

Microbial Anaerobic Digestion (Bio-Digesters) as an Approach to the Decontamination of Animal Wastes in Pollution Control and the Generation of Renewable Energy

PubMed Central

Manyi-Loh, Christy E.; Mamphweli, Sampson N.; Meyer, Edson L.; Okoh, Anthony I.; Makaka, Golden; Simon, Michael

2013-01-01

With an ever increasing population rate; a vast array of biomass wastes rich in organic and inorganic nutrients as well as pathogenic microorganisms will result from the diversified human, industrial and agricultural activities. Anaerobic digestion is applauded as one of the best ways to properly handle and manage these wastes. Animal wastes have been recognized as suitable substrates for anaerobic digestion process, a natural biological process in which complex organic materials are broken down into simpler molecules in the absence of oxygen by the concerted activities of four sets of metabolically linked microorganisms. This process occurs in an airtight chamber (biodigester) via four stages represented by hydrolytic, acidogenic, acetogenic and methanogenic microorganisms. The microbial population and structure can be identified by the combined use of culture-based, microscopic and molecular techniques. Overall, the process is affected by bio-digester design, operational factors and manure characteristics. The purpose of anaerobic digestion is the production of a renewable energy source (biogas) and an odor free nutrient-rich fertilizer. Conversely, if animal wastes are accidentally found in the environment, it can cause a drastic chain of environmental and public health complications. PMID:24048207

Microbial anaerobic digestion (bio-digesters) as an approach to the decontamination of animal wastes in pollution control and the generation of renewable energy.

PubMed

Manyi-Loh, Christy E; Mamphweli, Sampson N; Meyer, Edson L; Okoh, Anthony I; Makaka, Golden; Simon, Michael

2013-09-17

With an ever increasing population rate; a vast array of biomass wastes rich in organic and inorganic nutrients as well as pathogenic microorganisms will result from the diversified human, industrial and agricultural activities. Anaerobic digestion is applauded as one of the best ways to properly handle and manage these wastes. Animal wastes have been recognized as suitable substrates for anaerobic digestion process, a natural biological process in which complex organic materials are broken down into simpler molecules in the absence of oxygen by the concerted activities of four sets of metabolically linked microorganisms. This process occurs in an airtight chamber (biodigester) via four stages represented by hydrolytic, acidogenic, acetogenic and methanogenic microorganisms. The microbial population and structure can be identified by the combined use of culture-based, microscopic and molecular techniques. Overall, the process is affected by bio-digester design, operational factors and manure characteristics. The purpose of anaerobic digestion is the production of a renewable energy source (biogas) and an odor free nutrient-rich fertilizer. Conversely, if animal wastes are accidentally found in the environment, it can cause a drastic chain of environmental and public health complications.

Modified Anaerobic Digestion Model No.1 for dry and semi-dry anaerobic digestion of solid organic waste.

PubMed

Liotta, Flavia; Chatellier, Patrice; Esposito, Giovanni; Fabbricino, Massimiliano; Frunzo, Luigi; van Hullebusch, Eric D; Lens, Piet N L; Pirozzi, Francesco

2015-01-01

The role of total solids (TS) content in anaerobic digestion of selected complex organic matter, e.g. rice straw and food waste, was investigated. A range of TS from wet (4.5%) to dry (23%) was evaluated. A modified version of the Anaerobic Digestion Model No.1 for a complex organic substrate is proposed to take into account the effect of the TS content on anaerobic digestion. A linear function that correlates the kinetic constants of three specific processes (i.e. disintegration, acetate and propionate up-take) was included in the model. Results of biomethanation and volatile fatty acids production tests were used to calibrate the proposed model. Model simulations showed a good agreement between numerical and observed data.

Nutrition, Health, and Regulatory Aspects of Digestible Maltodextrins

PubMed Central

Hofman, Denise L.; van Buul, Vincent J.; Brouns, Fred J. P. H.

2016-01-01

Digestible maltodextrins are low-sweet saccharide polymers consisting of D-glucose units linked primarily linearly with alpha-1,4 bonds, but can also have a branched structure through alpha-1,6 bonds. Often, maltodextrins are classified by the amount of reducing sugars present relative to the total carbohydrate content; between 3 and 20 percent in the case of digestible maltodextrins. These relatively small polymers are used as food ingredients derived by hydrolysis from crops naturally rich in starch. Through advances in production technology, the application possibilities in food products have improved during the last 20 years. However, since glucose from digested maltodextrins is rapidly absorbed in the small intestine, the increased use has raised questions about potential effects on metabolism and health. Therefore, up-to-date knowledge concerning production, digestion, absorption, and metabolism of maltodextrins, including potential effects on health, were reviewed. Exchanging unprocessed starch with maltodextrins may lead to an increased glycemic load and therefore post meal glycaemia, which are viewed as less desirable for health. Apart from beneficial food technological properties, its use should accordingly also be viewed in light of this. Finally, this review reflects on regulatory aspects, which differ significantly in Europe and the United States, and, therefore, have implications for communication and marketing. PMID:25674937

Nutrition, Health, and Regulatory Aspects of Digestible Maltodextrins.

PubMed

Hofman, Denise L; van Buul, Vincent J; Brouns, Fred J P H

2016-09-09

Digestible maltodextrins are low-sweet saccharide polymers consisting of D-glucose units linked primarily linearly with alpha-1,4 bonds, but can also have a branched structure through alpha-1,6 bonds. Often, maltodextrins are classified by the amount of reducing sugars present relative to the total carbohydrate content; between 3 and 20 percent in the case of digestible maltodextrins. These relatively small polymers are used as food ingredients derived by hydrolysis from crops naturally rich in starch. Through advances in production technology, the application possibilities in food products have improved during the last 20 years. However, since glucose from digested maltodextrins is rapidly absorbed in the small intestine, the increased use has raised questions about potential effects on metabolism and health. Therefore, up-to-date knowledge concerning production, digestion, absorption, and metabolism of maltodextrins, including potential effects on health, were reviewed. Exchanging unprocessed starch with maltodextrins may lead to an increased glycemic load and therefore post meal glycaemia, which are viewed as less desirable for health. Apart from beneficial food technological properties, its use should accordingly also be viewed in light of this. Finally, this review reflects on regulatory aspects, which differ significantly in Europe and the United States, and, therefore, have implications for communication and marketing.

Influence of lactic acid on the two-phase anaerobic digestion of kitchen wastes.

PubMed

Zhang, Bo; Cai, Wei-min; He, Pin-jing

2007-01-01

To evaluate the influence of lactic acid on the methanogenesis, anaerobic digestion of kitchen wastes was firstly conducted in a two-phase anaerobic digestion process, and performance of two digesters fed with lactic acid and glucose was subsequently compared. The results showed that the lactic acid was the main fermentation products of hydrolysis-acidification stage in the two-phase anaerobic digestion process for kitchen wastes. The lactic acid concentration constituted approximately 50% of the chemical oxygen demand (COD) concentration in the hydrolysis-acidification liquid. The maximum organic loading rate was lower in the digester fed with lactic acid than that fed with glucose. Volatile fatty acids (VFAs) and COD removal were deteriorated in the methanogenic reactor fed with lactic acid compared to that fed with glucose. The specific methanogenic activity (SMA) declined to 0.343 g COD/(gVSSxd) when the COD loading were designated as 18.8 g/(Lxd) in the digester fed with lactic acid. The propionic acid accumulation occurred due to the high concentration of lactic acid fed. It could be concluded that avoiding the presence of the lactic acid is necessary in the hydrolysis-acidification process for the improvement of the two-phase anaerobic digestion process of kitchen wastes.

Spent coffee enhanced biomethane potential via an integrated hydrothermal carbonization-anaerobic digestion process.

PubMed

Codignole Luz, Fábio; Volpe, Maurizio; Fiori, Luca; Manni, Alessandro; Cordiner, Stefano; Mulone, Vincenzo; Rocco, Vittorio

2018-05-01

This study reports the implications of using spent coffee hydrochar as substrate for anaerobic digestion (AD) processes. Three different spent coffee hydrochars produced at 180, 220 and 250 °C, 1 h residence time, were investigated for their biomethane potential in AD process inoculated with cow manure. Spent coffee hydrochars were characterized in terms of ultimate, proximate and higher heating value (HHV), and their theoretical bio-methane yield evaluated using Boyle-Buswell equation and compared to the experimental values. The results were then analyzed using the modified Gompertz equation to determine the main AD evolution parameters. Different hydrochar properties were related to AD process performances. AD of spent coffee hydrochars produced at 180 °C showed the highest biomethane production rate (46 mL CH 4 /gVS . d), a biomethane potential of 491 mL/gVS (AD lasting 25 days), and a biomethane gas daily composition of about 70%. Copyright © 2018 Elsevier Ltd. All rights reserved.

PPARγ and Its Ligands: Potential Antitumor Agents in the Digestive System.

PubMed

Shu, Linjing; Huang, Renhuan; Wu, Songtao; Chen, Zhaozhao; Sun, Ke; Jiang, Yan; Cai, Xiaoxiao

2016-01-01

Peroxisome proliferator-activated receptor γ (PPARγ) is a versatile member of the ligand-activated nuclear hormone receptor superfamily of transcription factors, with expression in several different cell lines, especially in the digestive system. After being activated by its ligand, PPARγ can suppress the growth of oral, esophageal, gastric, colorectal, liver, biliary, and pancreatic tumor cells, suggesting that PPARγ ligand is a potential anticancer agent in PPARγ-expressing tumors. This review highlights key advances in understanding the effects of PPARγ ligands in the treatment of tumors in the digestive system.

Removal of tetracyclines, sulfonamides, and quinolones by industrial-scale composting and anaerobic digestion processes.

PubMed

Liu, Hang; Pu, Chengjun; Yu, Xiaolu; Sun, Ying; Chen, Junhao

2018-02-15

This study evaluated and compared the removal of antibiotics by industrial-scale composting and anaerobic digestion at different seasons. Twenty compounds belonged to three classes of widely used veterinary antibiotics (i.e., tetracyclines, sulfonamides, and quinolones) were investigated. Results show that of the three groups of antibiotics, tetracyclines were dominant in swine feces and poorly removed by anaerobic digestion with significant accumulation in biosolids, particularly in winter. Compared to that in winter, a much more effective removal (> 97%) by anaerobic digestion was observed for sulfonamides in summer. By contrast, quinolones were the least abundant antibiotics in swine feces and exhibited a higher removal by anaerobic digestion in winter than in summer. The overall removal of antibiotics by aerobic composting could be more than 90% in either winter or summer. Nevertheless, compost products from livestock farms in Beijing contained much higher antibiotics than commercial organic fertilizers. Thus, industrial composting standards should be strictly applied to livestock farms to further remove antibiotics and produce high quality organic fertilizer.

Processing recommendations for using low-solids digestate as nutrient solution for poly-ß-hydroxybutyrate production with Synechocystis salina.

PubMed

Meixner, K; Fritz, I; Daffert, C; Markl, K; Fuchs, W; Drosg, B

2016-12-20

Within the last decades, environmental pollution with persistent plastics steadily increased; therefore the production of biodegradable materials like poly-ß-hydroxybutyrate (PHB) is essential. Currently, PHB is produced with heterotrophic bacteria from crops. This leads to competition with food and feed production, which can be avoided by using photoautotrophic cyanobacteria, as Synechocystis salina, synthesizing PHB from CO 2 at nutrient limitation. This study aims to increase the economic efficiency of PHB production with cyanobacteria by using nutrients from anaerobic digestate. First, growth and PHB production of S. salina in digestate fractions (supernatant and permeate, with/without precipitating agents) and dilutions thereof and then the scale-up (photobioreactor, 200 L working volume) were evaluated. With precipitated and centrifuged digestate diluted 1/3 the highest biomass (1.55gL -1 ) and PHB concentrations (95.4mgL -1 ), being 78% of those in mineral media, were achieved. In the photobioreactor-experiments biomass (1.63gL -1 ) and PHB concentrations (88.7mgL -1 ), being 79% and 72% of those in mineral medium, were reached, but in a cultivation time 10days longer than in mineral medium. The possibility to use digestate as sustainable and low cost nutrient solution for microalgae cultivation and photoautotrophic PHB production, instead of applying it on fields or processing it to achieve discharge limits, makes this application a highly valid option. Copyright © 2016 Elsevier B.V. All rights reserved.

Impact of food industrial waste on anaerobic co-digestion of sewage sludge and pig manure.

PubMed

Murto, M; Björnsson, L; Mattiasson, B

2004-02-01

The performance of an anaerobic digestion process is much dependent on the type and the composition of the material to be digested. The effects on the degradation process of co-digesting different types of waste were examined in two laboratory-scale studies. In the first investigation, sewage sludge was co-digested with industrial waste from potato processing. The co-digestion resulted in a low buffered system and when the fraction of starch-rich waste was increased, the result was a more sensitive process, with process overload occurring at a lower organic loading rate (OLR). In the second investigation, pig manure, slaughterhouse waste, vegetable waste and various kinds of industrial waste were digested. This resulted in a highly buffered system as the manure contributed to high amounts of ammonia. However, it is important to note that ammonia might be toxic to the micro-organisms. Although the conversion of volatile fatty acids was incomplete the processes worked well with high gas yields, 0.8-1.0 m3 kg(-1) VS.

Environmental assessment of farm-scaled anaerobic co-digestion for bioenergy production

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lijó, Lucía, E-mail: lucia.lijo@usc.es; González-García, Sara; Bacenetti, Jacopo

Highlights: • Anaerobic monodigestion and codigestion were compared. • The environmental advantages of suitable waste management were proved. • The use of cereal crops as feedstock improves biogas yield. • Cultivation step implies the most important environmental hotspot. • Digestate management options were evaluated. - Abstract: The aim of this study was to assess the environmental profile of a bioenergy system based on a co-digestion plant using maize silage and pig slurry as substrates. All the processes involved in the production of bioenergy as well as the avoided processes accrued from the biogas production system were evaluated. The results evidencedmore » the environmental importance of the cultivation step and the environmental credits associated to the avoided processes. In addition, this plant was compared with two different plants that digest both substrates separately. The results revealed the environmental benefits of the utilisation of pig slurry due to the absence of environmental burdens associated with its production as well as credits provided when avoiding its conventional management. The results also presented the environmental drawbacks of the utilisation of maize silage due to the environmental burdens related with its production. Accordingly, the anaerobic mono-digestion of maize silage achieved the worst results. The co-digestion of both substrates was ranked in an intermediate position. Additionally, three possible digestate management options were assessed. The results showed the beneficial effect of digestate application as an organic fertiliser, principally on account of environmental credits due to avoided mineral fertilisation. However, digestate application involves important acidifying and eutrophicating emissions.« less

Anaerobic digestion of slaughterhouse waste: main process limitations and microbial community interactions.

PubMed

Palatsi, J; Viñas, M; Guivernau, M; Fernandez, B; Flotats, X

2011-02-01

Fresh pig/cattle slaughterhouse waste mixtures, with different lipid-protein ratios, were characterized and their anaerobic biodegradability assessed in batch tests. The resultant methane potentials were high (270-300 L(CH4) kg(-1)(COD)) making them interesting substrates for the anaerobic digestion process. However, when increasing substrate concentrations in consecutive batch tests, up to 15 g(COD) kg(-1), a clear inhibitory process was monitored. Despite the reported severe inhibition, related to lipid content, the system was able to recover activity and successfully degrade the substrate. Furthermore, 16SrRNA gene-based DGGE results showed an enrichment of specialized microbial populations, such as β-oxidizing/proteolitic bacteria (Syntrophomonas sp., Coprothermobacter sp. and Anaerobaculum sp.), and syntrophic methanogens (Methanosarcina sp.). Consequently, the lipid concentration of substrate and the structure of the microbial community are the main limiting factors for a successful anaerobic treatment of fresh slaughterhouse waste. Copyright © 2010 Elsevier Ltd. All rights reserved.

Effect of Recycle Sludge on Anaerobic Digestion of Palm Oil Mill Effluent in A Thermophilic Continuous Digester

NASA Astrophysics Data System (ADS)

Irvan; Trisakti, B.; Tomiuchi, Y.; Harahap, U.; Daimon, H.

2017-06-01

The objective of this research is to maintain short retention time and high degradation of palm oil mill effluent (POME) to biogas by applying recycle sludge. Fresh POME from Rambutan Mill without further treatment was used as feed. Two lab-scale digesters supported from Metawater Co. Ltd. have been applied to treat POME at thermophilic (55°C) condition. Both digesters were operated under intermittent operation mode. Experiments were performed in two methods: with and without recycle sludge. Hydraulic retention time (HRT) of both methods was maintained at 6 days, while sludge retention time (SRT) was maintained at various days. The result showed that by extending SRT in return sludge process where 25% of digested slurry recycled to the digester, improvement of volatile solid (VS) decomposition was obtained around 84% at HRT of 6 days and SRT of 21 days. Then, chemical oxygen demand (COD) removal efficiency could be reached until 85% by using recycle sludge.

Performance assessment of two-stage anaerobic digestion of kitchen wastes.

PubMed

Bo, Zhang; Pin-Jing, He

2014-01-01

This study is aimed at investigating the performance of the two-phase anaerobic digestion of kitchen wastes in a lab-scale setup. The semi-continuous experiment showed that the two-phase anaerobic digestion of kitchen wastes had a bioconversion rate of 83%, biogas yield of 338 mL x (g chemical oxygen demand (COD))(-1) and total solid conversion of 63% when the entire two-phase anaerobic digestion process was subjected to an organic loading rate (OLR) of 10.7 g x (L d)(-1). In the hydrolysis-acidogenesis process, the efficiency of solubilization decreased from 72.6% to 41.1%, and the acidogenesis efficiency decreased from 31.8% to 17.8% with an increase in the COD loading rate. On the other hand, the performance of the subsequent methanogenic process was not susceptible to the increase in the feeding COD loading rate in the hydrolysis-acidogenesis stage. Lactic acid was one of the main fermentation products, accounting for over 40% of the total soluble COD in the fermentation liquid. The batch experiments indicated that the lactic acid was the earliest predominant fermentation product, and distributions of fermentation products were pH dependent. Results showed that increasing the feeding OLR of kitchen wastes made the two-stage anaerobic digestion process more effective. Moreover, there was a potential improvement in the performance of anaerobic digestion of kitchen wastes with a corresponding improvement in the hydrolysis process.

[Survival of probiotic microorganisms in the conditions in vitro imitating the process of human digestion].

PubMed

Darmov, I V; Chicherin, I Iu; Pogorel'skiĭ, I P; Lundovskikh, I A

2011-01-01

Assessment of survival bifidobacteria and lactobacteria under the conditions in vitro, simulating digestion in human stomach and intestine, and study of survival probiotic and indigenous microorganisms in co-cultivation on solid nutrient medium. Probiotic microorganisms from commercial preparations Bifidobacterin and Lactobacterin, clinical isolates lactobacillus (Lactobacillus acidophilus No 1, L. brevis No 2) were used in experiments. Survival study of probiotic microorganisms was performed on a model in vitro, simulating the process of digestion in the human body. Assessment of the relationship of probiotic microorganisms and indigenous microorganisms was carried out in co-cultivation in vitro on solid nutrient medium. A significant reduction in the number of viable probiotic microorganisms during their incubation in model media was set as well as suppression of probiotic microorganisms growth by cultures of a clinical strains of lactobacillus, corresponding to biocompatibility by type "host against probiotic". While choosing probiotics in the treatment of dysbacterioses the character of relationship between probiotic microorganisms and indigenous microorganisms of a patient is recommended to be preliminarily tested. Also microorganisms of own microflora should be stimulated using modern prebiotics.

Development and validation of a simplified titration method for monitoring volatile fatty acids in anaerobic digestion.

PubMed

Sun, Hao; Guo, Jianbin; Wu, Shubiao; Liu, Fang; Dong, Renjie

2017-09-01

The volatile fatty acids (VFAs) concentration has been considered as one of the most sensitive process performance indicators in anaerobic digestion (AD) process. However, the accurate determination of VFAs concentration in AD processes normally requires advanced equipment and complex pretreatment procedures. A simplified method with fewer sample pretreatment procedures and improved accuracy is greatly needed, particularly for on-site application. This report outlines improvements to the Nordmann method, one of the most popular titrations used for VFA monitoring. The influence of ion and solid interfering subsystems in titrated samples on results accuracy was discussed. The total solid content in titrated samples was the main factor affecting accuracy in VFA monitoring. Moreover, a high linear correlation was established between the total solids contents and VFA measurement differences between the traditional Nordmann equation and gas chromatography (GC). Accordingly, a simplified titration method was developed and validated using a semi-continuous experiment of chicken manure anaerobic digestion with various organic loading rates. The good fitting of the results obtained by this method in comparison with GC results strongly supported the potential application of this method to VFA monitoring. Copyright © 2017. Published by Elsevier Ltd.

Anaerobic digestion of selected Italian agricultural and industrial residues (grape seeds and leather dust): combined methane production and digestate characterization.

PubMed

Caramiello, C; Lancellotti, I; Righi, F; Tatàno, F; Taurino, R; Barbieri, L

2013-01-01

A combined experimental evaluation of methane production (obtained by anaerobic digestion) and detailed digestate characterization (with physical-chemical, thermo-gravimetric and mineralogical approaches) was conducted on two organic substrates, which are specific to Italy (at regional and national levels). One of the substrates was grape seeds, which have an agricultural origin, whereas the other substrate was vegetable-tanned leather dust, which has an industrial origin. Under the assumed experimental conditions of the performed lab-scale test series, the grape seed substrate exhibited a resulting net methane production of 175.0 NmL g volatile solids (VS)(-1); hence, it can be considered as a potential energy source via anaerobic digestion. Conversely, the net methane production obtained from the anaerobic digestion of the vegetable-tanned leather dust substrate was limited to 16.1 NmL gVS(-1). A detailed characterization of the obtained digestates showed that there were both nitrogen-containing compounds and complex organic compounds present in the digestate that was obtained from the mixture of leather dust and inoculum. As a general perspective of this experimental study, the application of diversified characterization analyzes could facilitate (1) a better understanding of the main properties of the obtained digestates to evaluate their potential valorization, and (2) a combination of the digestate characteristics with the corresponding methane productions to comprehensively evaluate the bioconversion process.

Resampling: A Marriage of Computers and Statistics. ERIC/TM Digest.

ERIC Educational Resources Information Center

Rudner, Lawrence M.; Shafer, Mary Morello

Advances in computer technology are making it possible for educational researchers to use simpler statistical methods to address a wide range of questions with smaller data sets and fewer, and less restrictive, assumptions. This digest introduces computationally intensive statistics, collectively called resampling techniques. Resampling is a…

Very high expander processing of maize on animal performance, digestibility and product quality of finishing pigs and broilers.

PubMed

Puntigam, R; Schedle, K; Schwarz, C; Wanzenböck, E; Eipper, J; Lechner, E-M; Yin, L; Gierus, M

2018-07-01

The present study investigated the effect of hydrothermic maize processing and supplementation of amino acids (AA) in two experiments. In total, 60 barrows and 384 broilers were fed four diets including either unprocessed (T1), or hydrothermically processed maize, that is short- (T2), or long-term conditioned (LC) (T3), and subsequently expanded maize of the same batch. Assuming a higher metabolizable energy (ME) content after processing, the fourth diet (T4) contains maize processed as treatment T3, but AA were supplemented to maintain the ideal protein value. Performance, digestibility and product quality in both species were assessed. Results show that in pigs receiving T4 the average daily feed intake was lower compared with the other treatments, whereas no difference was observed in broilers. The T3 improved the feed conversion rate compared with T1 (P<0.10) for both species. In contrast, average daily gain (ADG) (1277 g/day for T2 and 1267 g/day for T3 v. 971 g/day for T1) was only altered in pigs. The hydrothermic maize processing increased the apparent total tract digestibility (ATTD) of dry matter, starch and ether extract after acid hydrolysis. This may be a consequence of higher ATTD of gross energy in the finishing phase for both animal species, suggesting a higher ME content in diets with processed maize. The higher ME content of diets with processed maize is supported also by measurements of product quality. Supplementation of AA in T4 enhanced the loin depth in pigs as well as the amount of breast meat in broilers. Further effects of processing maize on meat quality were the reduced yellowness and antioxidative capacity (P<0.10) for broilers, likely due to the heat damage of xanthophylls and tocopherols. Processing also increased springiness and chewiness (P<0.10) of the broilers breast meat, whereas the loin meat of pigs showed a decreased lightness and yellowness (P<0.10) in meat when hydrothermic processed maize was used (for T2, T3 and T4). LC

Changes in the microbial communities during co-composting of digestates.

PubMed

Franke-Whittle, Ingrid H; Confalonieri, Alberto; Insam, Heribert; Schlegelmilch, Mirko; Körner, Ina

2014-03-01

Anaerobic digestion is a waste treatment method which is of increasing interest worldwide. At the end of the process, a digestate remains, which can gain added value by being composted. A study was conducted in order to investigate microbial community dynamics during the composting process of a mixture of anaerobic digestate (derived from the anaerobic digestion of municipal food waste), green wastes and a screened compost (green waste/kitchen waste compost), using the COMPOCHIP microarray. The composting process showed a typical temperature development, and the highest degradation rates occurred during the first 14 days of composting, as seen from the elevated CO2 content in the exhaust air. With an exception of elevated nitrite and nitrate levels in the day 34 samples, physical-chemical parameters for all compost samples collected during the 63 day process indicated typical composting conditions. The microbial communities changed over the 63 days of composting. According to principal component analysis of the COMPOCHIP microarray results, compost samples from the start of the experiment were found to cluster most closely with the digestate and screened compost samples. The green waste samples were found to group separately. All starting materials investigated were found to yield fewer and lower signals when compared to the samples collected during the composting experiment. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

Anaerobic sludge digestion with a biocatalytic additive. [Lactobacillus acidophilus

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ghosh, S.; Henry, M.P.; Fedde, P.A.

1982-01-01

Aimed at improving the process operating characteristics of anaerobic digestion for sludge stabilization and SNG production, this study evaluates the effects of a lactobacillus additive under normal, variable, and overload conditions. This whey fermentation product of an acid-tolerant strain of L. acidophilus fortified with CoCO/sub 3/, (NH/sub 4/)/sub 2/HPO/sub 4/, ferrous lactate, and lactic acid provides growth factors, metabolic intermediates, and enzymes needed for substrate degradation and cellular synthesis. Data indicate that the biochemical additive increases methane yield, gas production rate, and volatile solids reduction; decreases volatile acids accumulation; enhances the digester buffer capacity; and improves the fertilizer value andmore » dewatering characteristics of the digested residue. Digester capacities could be potentially doubled when the feed is so treated. Results of field tests with six full-scale digesters confirm observations made with bench-scale digesters.« less

Effect of cooking and in vitro digestion on the stability of co-enzyme Q10 in processed meat products.

PubMed

Tobin, Brian D; O'Sullivan, Maurice G; Hamill, Ruth; Kerry, Joseph P

2014-05-01

The use of CoQ10 fortification in the production of a functional food has been demonstrated in the past but primarily for dairy products. This study aimed to determine the bio-accessibility of CoQ10 in processed meat products, beef patties and pork breakfast sausages, fortified with CoQ10. Both the patties and sausages were fortified with a micellarized form of CoQ10 to enhance solubility to a concentration of 1mg/g of sample (NovaSolQ®). An assay was developed combining in vitro digestion and HPLC analysis to quantify the CoQ10 present in fortified products (100mg/g). The cooking retention level of CoQ10 in the products was found to be 74±1.42% for patties and 79.69±0.75% for sausages. The digestibility for both products ranged between 93% and 95%, sausages did have a higher digestibility level than patties but this was not found to be significant (P<0.01). Copyright © 2013 Elsevier Ltd. All rights reserved.

Energetic and biochemical valorization of cork boiling wastewater by anaerobic digestion.

PubMed

Marques, Isabel Paula; Gil, Luís; La Cara, Francesco

2014-01-01

In addition to energy benefits, anaerobic digestion offers other interesting advantages. The cork industry is of great environmental, economic and social significance in the western Mediterranean region, with Portugal being the world-leading producer and exporter. Cork boiling wastewater (CBW) is a toxic and recalcitrant organic effluent produced by this sector, which constitutes a serious environmental hazard. However, there is no documented research on anaerobic treatment/valorization performed with this effluent. The work presented here was developed with the aim to use the anaerobic digestion process to convert the CBW polluting organic load into an energy carrier gas and valuable molecules for industry. No lag phases were observed and a methane yield of 0.126 to 0.142 m(3) kg(-1) chemical oxygen demand (COD)added was registered in the mesophilic consortium experiments carried out in batch flasks at 37 ± 1°C. Anaerobic digestion can be advantageously connected to ultrafiltration or electrochemical processes, due to the following: 1) reduction of ellagic acid content and consequent decrease of CBW viscosity; and 2) increase in conductivity after the anaerobic process, avoiding the electrolyte application of the electrochemical process. The improvement of several CBW biochemical features shows that anaerobic digestion may provide additionally useful molecules. The rise in concentration of some of these compounds, belonging to the benzoic acid family (gallic, protocatechuic, vanillic and syringic acids), is responsible for the increase of antiradical activity of the phenolic fraction. Additionally, some enzymatic activity was also observed and while the laccase activity increased in the digested effluent by anaerobiosis, xylanase was formed in the process. The multidisciplinary approach adopted allowed the valorization of CBW in terms of energy and valuable biomolecules. By exploiting the anaerobic digestion process potential, a novel methodology to toxic

Energetic and biochemical valorization of cork boiling wastewater by anaerobic digestion

PubMed Central

2014-01-01

Background In addition to energy benefits, anaerobic digestion offers other interesting advantages. The cork industry is of great environmental, economic and social significance in the western Mediterranean region, with Portugal being the world-leading producer and exporter. Cork boiling wastewater (CBW) is a toxic and recalcitrant organic effluent produced by this sector, which constitutes a serious environmental hazard. However, there is no documented research on anaerobic treatment/valorization performed with this effluent. The work presented here was developed with the aim to use the anaerobic digestion process to convert the CBW polluting organic load into an energy carrier gas and valuable molecules for industry. Results No lag phases were observed and a methane yield of 0.126 to 0.142 m3 kg-1 chemical oxygen demand (COD)added was registered in the mesophilic consortium experiments carried out in batch flasks at 37 ± 1°C. Anaerobic digestion can be advantageously connected to ultrafiltration or electrochemical processes, due to the following: 1) reduction of ellagic acid content and consequent decrease of CBW viscosity; and 2) increase in conductivity after the anaerobic process, avoiding the electrolyte application of the electrochemical process. The improvement of several CBW biochemical features shows that anaerobic digestion may provide additionally useful molecules. The rise in concentration of some of these compounds, belonging to the benzoic acid family (gallic, protocatechuic, vanillic and syringic acids), is responsible for the increase of antiradical activity of the phenolic fraction. Additionally, some enzymatic activity was also observed and while the laccase activity increased in the digested effluent by anaerobiosis, xylanase was formed in the process. Conclusions The multidisciplinary approach adopted allowed the valorization of CBW in terms of energy and valuable biomolecules. By exploiting the anaerobic digestion process potential, a

Verification Of The Defense Waste Processing Facility's (DWPF) Process Digestion Methods For The Sludge Batch 8 Qualification Sample

DOE Office of Scientific and Technical Information (OSTI.GOV)

Click, D. R.; Edwards, T. B.; Wiedenman, B. J.

2013-03-18

This report contains the results and comparison of data generated from inductively coupled plasma – atomic emission spectroscopy (ICP-AES) analysis of Aqua Regia (AR), Sodium Peroxide/Sodium Hydroxide Fusion Dissolution (PF) and Cold Chem (CC) method digestions and Cold Vapor Atomic Absorption analysis of Hg digestions from the DWPF Hg digestion method of Sludge Batch 8 (SB8) Sludge Receipt and Adjustment Tank (SRAT) Receipt and SB8 SRAT Product samples. The SB8 SRAT Receipt and SB8 SRAT Product samples were prepared in the SRNL Shielded Cells, and the SRAT Receipt material is representative of the sludge that constitutes the SB8 Batch ormore » qualification composition. This is the sludge in Tank 51 that is to be transferred into Tank 40, which will contain the heel of Sludge Batch 7b (SB7b), to form the SB8 Blend composition.« less

Application of Anaerobic Digestion Model No. 1 for simulating anaerobic mesophilic sludge digestion

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mendes, Carlos, E-mail: carllosmendez@gmail.com; Esquerre, Karla, E-mail: karlaesquerre@ufba.br; Matos Queiroz, Luciano, E-mail: lmqueiroz@ufba.br

2015-01-15

Highlights: • The behavior of a anaerobic reactor was evaluated through modeling. • Parametric sensitivity analysis was used to select most sensitive of the ADM1. • The results indicate that the ADM1 was able to predict the experimental results. • Organic load rate above of 35 kg/m{sup 3} day affects the performance of the process. - Abstract: Improving anaerobic digestion of sewage sludge by monitoring common indicators such as volatile fatty acids (VFAs), gas composition and pH is a suitable solution for better sludge management. Modeling is an important tool to assess and to predict process performance. The present studymore » focuses on the application of the Anaerobic Digestion Model No. 1 (ADM1) to simulate the dynamic behavior of a reactor fed with sewage sludge under mesophilic conditions. Parametric sensitivity analysis is used to select the most sensitive ADM1 parameters for estimation using a numerical procedure while other parameters are applied without any modification to the original values presented in the ADM1 report. The results indicate that the ADM1 model after parameter estimation was able to predict the experimental results of effluent acetate, propionate, composites and biogas flows and pH with reasonable accuracy. The simulation of the effect of organic shock loading clearly showed that an organic shock loading rate above of 35 kg/m{sup 3} day affects the performance of the reactor. The results demonstrate that simulations can be helpful to support decisions on predicting the anaerobic digestion process of sewage sludge.« less

Effect of different pH-values on process parameters in two-phase anaerobic digestion of high-solid substrates.

PubMed

Lindner, Jonas; Zielonka, Simon; Oechsner, Hans; Lemmer, Andreas

2015-01-01

In many publications, primary fermentation is described as a limiting step in the anaerobic digestion of fibre-rich biomass [Eastman JA, Ferguson JF. Solubilization of particulacte carbon during the anaerobic digeston. J WPCF. 1981;53:352-366; Noike T, Endo G, Chang J, Yaguchi J, Matsumoto J. Characteristics of carbohydrate degradation and the rate-limiting step in anaerobic digestion. Biotechnol Bioeng. 1985;27:1482-1489; Arntz HJ, Stoppok E, Buchholz K. Anaerobic hydroysis of beet pulp-discontiniuous experiments. Biotechnol Lett. 1985;7:113-118]. The microorganisms of the primary fermentation process differ widely from the methanogenic microorganisms [Pohland FG, Ghosh S. Developments in anaerobic stabilization of organic wastes-the two-phase concept. Environ Lett. 1971;1:255-266]. To optimize the biogas process, a separation in two phases is suggested by many authors [Fox P, Pohland GK. Anaerobic treatment applications and fundamentals: substrate specificity during phase separation. Water Environ Res. 1994;66:716-724; Cohen A, Zoetemeyer RJ, van Deursen A, van Andel JG. Anaerobic digestion of glucose with separated acid production and methane formation. Water Res. 1979;13:571-580]. To carry out the examination, a two-phase laboratory-scale biogas plant was established, with a physical phase separation. In previous studies, the regulation of the pH-value during the acid formation was usually carried out by the addition of sodium hydroxide [Cohen A, Zoetemeyer RJ, van Deursen A, van Andel JG. Anaerobic digestion of glucose with separated acid production and methane formation. Water Res. 1979;13:571-580; Ueno Y, Tatara M, Fukui H, Makiuchi T, Goto M, Sode K. Production of hydrogen and methane from organic solid wastes by phase separation of anaerobic process. Bioresour Technol. 2007;98:1861-1865; Zoetemeyer RJ, van den Heuvel JC, Cohen A. pH influence on acidogenic dissimilation of glucose in an anaerobic digestor. Water Res. 1982;16:303-311]. A new technology

HANDBOOK ON ADVANCED PHOTOCHEMICAL OXIDATION PROCESSES

EPA Science Inventory

This handbook summarizes commercial-scale system performance and cost data for advanced photochemical oxidation (APO) treatment of contaminated water, air, and solids. Similar information from pilot- and bench-scale evaluations of APO processes is also included to supplement the...

Effect of Acylglycerol Composition and Fatty Acyl Chain Length on Lipid Digestion in pH-Stat Digestion Model and Simulated In Vitro Digestion Model.

PubMed

Qi, Jin F; Jia, Cai H; Shin, Jung A; Woo, Jeong M; Wang, Xiang Y; Park, Jong T; Hong, Soon T; Lee, K-T

2016-02-01

In this study, a pH-stat digestion model and a simulated in vitro digestion model were employed to evaluate the digestion degree of lipids depending on different acylglycerols and acyl chain length (that is, diacylglycerol [DAG] compared with soybean oil representing long-chain triacylglycerol compared with medium-chain triacylglycerol [MCT]). In the pH-stat digestion model, differences were observed among the digestion degrees of 3 oils using digestion rate (k), digestion half-time (t1/2 ), and digestion extent (Φmax). The results showed the digestion rate order was MCT > soybean oil > DAG. Accordingly, the order of digestion half-times was MCT < soybean oil < DAG. In simulated in vitro digestion model, digestion rates (k') and digestion half-times (t'1/2 ) were also obtained and the results showed a digestion rate order of MCT (k' = 0.068 min(-1) ) > soybean oil (k' = 0.037 min(-1) ) > DAG (k' = 0.024 min(-1) ). Consequently, the order of digestion half-times was MCT (t'1/2 = 10.20 min) < soybean oil (t'1/2 = 18.74 min) < DAG (t'1/2 = 29.08 min). The parameters obtained using the 2 models showed MCT was digested faster than soybean oil, and that soybean oil was digested faster than DAG. © 2015 Institute of Food Technologists®

Gastric digestion of raw and roasted almonds in vivo

USDA-ARS?s Scientific Manuscript database

Almonds are an important dietary source of lipids, protein, and alpha-tocopherol. It has been demonstrated that the physical form of almond kernels will affect their digestion and absorption, but the influence of thermal processes on the digestion of almonds has received little attention. The obje...

Mathematical modelling of disintegration-limited co-digestion of OFMSW and sewage sludge.

PubMed

Esposito, G; Frunzo, L; Panico, A; d'Antonio, G

2008-01-01

This paper presents a mathematical model able to simulate under dynamic conditions the physical, chemical and biological processes prevailing in a OFMSW and sewage sludge anaerobic digestion system. The model proposed is based on differential mass balance equations for substrates, products and bacterial groups involved in the co-digestion process and includes the biochemical reactions of the substrate conversion and the kinetics of microbial growth and decay. The main peculiarity of the model is the surface based kinetic description of the OFMSW disintegration process, whereas the pH determination is based on a nine-order polynomial equation derived by acid-base equilibria. The model can be applied to simulate the co-digestion process for several purposes, such as the evaluation of the optimal process conditions in terms of OFMSW/sewage sludge ratio, temperature, OFMSW particle size, solid mixture retention time, reactor stirring rate, etc. Biogas production and composition can also be evaluated to estimate the potential energy production under different process conditions. In particular, model simulations reported in this paper show the model capability to predict the OFMSW amount which can be treated in the digester of an existing MWWTP and to assess the OFMSW particle size diminution pre-treatment required to increase the rate of the disintegration process, which otherwise can highly limit the co-digestion system. Copyright IWA Publishing 2008.

HANDBOOK ON ADVANCED NONPHOTOCHEMICAL OXIDATION PROCESSES

EPA Science Inventory

The purpose of this handbook is to summarize commercial-scale system performance and cost data for advanced nonphotochemical oxidation (ANPO) treatment of contaminated water, air, and soil. Similar information from pilot-and bench-scale evaluations of ANPO processes is also inclu...

Use of hydrodynamic disintegration to accelerate anaerobic digestion of surplus activated sludge.

PubMed

Grübel, Klaudiusz; Machnicka, Alicja

2009-12-01

Hydrodynamic disintegration of activated sludge resulted in organic matter and polymers transfer from the solid phase into the liquid phase. Disintegration by hydrodynamic cavitation had a positive effect on the degree and rate of excess sludge anaerobic digestion. Also, addition of a part of anaerobic digested sludge containing adapted microorganisms resulted in acceleration of the process. The disruption of cells of foam microorganisms and addition to the digestion process led to an increase of biogas production.

Biogas by semi-continuous anaerobic digestion of food waste.

PubMed

Zhang, Cunsheng; Su, Haijia; Wang, Zhenbin; Tan, Tianwei; Qin, Peiyong

2015-04-01

The semi-continuous anaerobic digestion of food waste was investigated in 1-L and 20-L continuously stirred tank reactors (CSTRs), to identify the optimum operation condition and the methane production of the semi-continuous anaerobic process. Results from a 1-L digester indicated that the optimum organic loading rate (OLR) for semi-continuous digestion is 8 g VS/L/day. The corresponding methane yield and chemical oxygen demand (COD) reduction were 385 mL/g VS and 80.2 %, respectively. Anaerobic digestion was inhibited at high OLRs (12 and 16 g VS/L/day), due to volatile fatty acid (VFA) accumulation. Results from a 20-L digester indicated that a higher methane yield of 423 mL/g VS was obtained at this larger scale. The analysis showed that the methane production at the optimum OLR fitted well with the determined kinetics equation. An obvious decrease on the methane content was observed at the initial of digestion. The increased metabolization of microbes and the activity decrease of methanogen caused by VFA accumulation explained the lower methane content at the initial of digestion.

Effect of Different Heat Treatments on In Vitro Digestion of Egg White Proteins and Identification of Bioactive Peptides in Digested Products.

PubMed

Wang, Xuefen; Qiu, Ning; Liu, Yaping

2018-04-01

Chicken eggs are ingested by people after a series of processes, but to date, only a few studies have explored the nutrient variations caused by different heat treatments. In this work, the impacts of different heat treatments (4, 56, 65, and 100 °C on the in vitro digestibility of egg white proteins were investigated by hydrolysis with pepsin or pepsin + pancreatin to simulate human gastrointestinal digestion, and the digested products were identified using Nano-LC-ESI-MS/MS. Egg white proteins treated at 65 °C had the highest in vitro pepsin digestibility value whereas the pepsin + pancreatin digestibility increased significantly (P < 0.05) as the cooking temperature was raised. The molecular weight distribution of the digested products indicated that, when compared to pepsin-treated samples, pepsin + pancreatin-treated samples contained more low-molecular-weight peptides (m/z < 849.2) with higher signal intensities. The number of unique peptides identified in every digestion product showed a positive correlation with their in vitro digestibility. Additionally, bioactive peptides such as antioxidant, antimicrobial and antihypertensive peptides were found present in egg white digested products, especially in samples treated at 4 and 100 °C. These findings may facilitate a better understanding of nutritive values of egg white proteins and their digested products under different cooking temperatures, such as antibacterial and antioxidant peptides identified in the digestion samples treated, respectively at 4 and 100 °C. This study also provided information for improving the applications of eggs in the food industry as well as a theoretical basis for egg consumption. © 2018 Institute of Food Technologists®.

Co-digestion of sewage sludge from external small WWTP's in a large plant

NASA Astrophysics Data System (ADS)

Miodoński, Stanisław

2017-11-01

Improving energy efficiency of WWTPs (Waste Water Treatment Plants) is crucial action of modern wastewater treatment technology. Technological treatment process optimization is important but the main goal will not be achieved without increasing production of renewable energy from sewage sludge in anaerobic digestion process which is most often used as sludge stabilization method on large WWTP's. Usually, anaerobic digestion reactors used for sludge digestion were designed with reserve and most of them is oversized. In many cases that reserve is unused. On the other hand, smaller WWTPs have problem with management of sewage sludge due to lack of adequately developed infrastructure for sludge stabilization. Paper shows an analysis of using a technological reserve of anaerobic digestion reactors at large WWTP (1 million P.E.) for sludge stabilization collected from smaller WWTP in a co-digestion process. Over 30 small WWTPs from the same region as the large WWTP were considered in this study. Furthermore, performed analysis included also evaluation of potential sludge disintegration pre-treatment for co-digestion efficiency improvement.

Phenolic compounds, antioxidant potential and antiproliferative potential of 10 common edible flowers from China assessed using a simulated in vitro digestion-dialysis process combined with cellular assays.

PubMed

Huang, Weisu; Mao, Shuqin; Zhang, Liuquan; Lu, Baiyi; Zheng, Lufei; Zhou, Fei; Zhao, Yajing; Li, Maiquan

2017-11-01

Phenolic compounds could be sensitive to digestive conditions, thus a simulated in vitro digestion-dialysis process and cellular assays was used to determine phenolic compounds and antioxidant and antiproliferative potentials of 10 common edible flowers from China and their functional components. Gallic acid, ferulic acid, and rutin were widely present in these flowers, which demonstrated various antioxidant capacities (DPPH, ABTS, FRAP and CAA values) and antiproliferative potentials measured by the MTT method. Rosa rugosa, Paeonia suffruticosa and Osmanthus fragrans exhibited the best antioxidant and antiproliferative potentials against HepG2, A549 and SGC-7901 cell lines, except that Osmanthus fragrans was not the best against SGC-7901 cells. The in vitro digestion-dialysis process decreased the antioxidant potential by 33.95-90.72% and the antiproliferative potential by 13.22-87.15%. Following the in vitro digestion-dialysis process, phenolics were probably responsible for antioxidant (R 2 = 0.794-0.924, P < 0.01) and antiproliferative (R 2 = 0.408-0.623, P < 0.05) potential. Moreover, gallic acid may be responsible for the antioxidant potential of seven flowers rich in edible flowers. The antioxidant and antiproliferative potential of 10 edible flowers revealed a clear decrease after digestion and dialysis along with the reduction of phenolics. Nevertheless, they still had considerable antioxidant and antiproliferative potential, which merited further investigation in in vivo studies. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Impact of different particle size distributions on anaerobic digestion of the organic fraction of municipal solid waste.

PubMed

Zhang, Y; Banks, C J

2013-02-01

Particle size may significantly affect the speed and stability of anaerobic digestion, and matching the choice of particle size reduction equipment to digester type can thus determine the success or failure of the process. In the current research the organic fraction of municipal solid waste was processed using a combination of a shear shredder, rotary cutter and wet macerator to produce streams with different particle size distributions. The pre-processed waste was used in trials in semi-continuous 'wet' and 'dry' digesters at organic loading rate (OLR) up to 6kg volatile solids (VS) m(-3)day(-1). The results indicated that while difference in the particle size distribution did not change the specific biogas yield, the digester performance was affected. In the 'dry' digesters the finer particle size led to acidification and ultimately to process failure at the highest OLR. In 'wet' digestion a fine particle size led to severe foaming and the process could not be operated above 5kgVSm(-3)day(-1). Although the trial was not designed as a direct comparison between 'wet' and 'dry' digestion, the specific biogas yield of the 'dry' digesters was 90% of that produced by 'wet' digesters fed on the same waste at the same OLR. Copyright © 2012 Elsevier Ltd. All rights reserved.

Experience of curing serious obstruction of advanced-stage upper digestive tract tumor using laser under endoscope

NASA Astrophysics Data System (ADS)

Mu, Hai-Bin; Zhang, Man-Ling; Zhang, Xiao-Qiang; Zhang, Feng-Qiu; Kong, De-Jia; Tang, Li-Bin

1998-11-01

The patients who suffer from upper digestive tract tumor, such as cancer of esophagus, cancer of cardia, all have serious obstruction and fail to get nutrition and can not bear the strike of the radiotherapy and chemotherapy. In order to reduce the obstruction symptom and suffering of the patients and to prolong their life time, since 1989, our hospital used the laser to cure the upper digestive tract tumor 11 cases with serious obstruction and got remarkable curative effect.

Process Recovery after CaO Addition Due to Granule Formation in a CSTR Co-Digester-A Tool to Influence the Composition of the Microbial Community and Stabilize the Process?

PubMed

Liebrich, Marietta; Kleyböcker, Anne; Kasina, Monika; Miethling-Graff, Rona; Kassahun, Andrea; Würdemann, Hilke

2016-03-17

The composition, structure and function of granules formed during process recovery with calcium oxide in a laboratory-scale fermenter fed with sewage sludge and rapeseed oil were studied. In the course of over-acidification and successful process recovery, only minor changes were observed in the bacterial community of the digestate, while granules appeared during recovery. Fluorescence microscopic analysis of the granules showed a close spatial relationship between calcium and oil and/or long chain fatty acids. This finding further substantiated the hypothesis that calcium precipitated with carbon of organic origin and reduced the negative effects of overloading with oil. Furthermore, the enrichment of phosphate minerals in the granules was shown, and molecular biological analyses detected polyphosphate-accumulating organisms as well as methanogenic archaea in the core. Organisms related to Methanoculleus receptaculi were detected in the inner zones of a granule, whereas they were present in the digestate only after process recovery. This finding indicated more favorable microhabitats inside the granules that supported process recovery. Thus, the granule formation triggered by calcium oxide addition served as a tool to influence the composition of the microbial community and to stabilize the process after overloading with oil.

Effects of organic composition on mesophilic anaerobic digestion of food waste.

PubMed

Li, Yangyang; Jin, Yiying; Borrion, Aiduan; Li, Hailong; Li, Jinhui

2017-11-01

Anaerobic digestion of food waste (FW) has been widely investigated, however, little is known about the influence of organic composition on the FW digestion process. This study aims to identify the optimum composition ratios of carbohydrate (CA), protein (CP) and lipid (EE) for maintaining high methane yield and process stability. The results show that the CA-CP-EE ratio was significantly correlated with performance and degradability parameters. Controlling the CA-CP-EE ratio higher than 1.89 (CA higher than 8.3%, CP lower than 5.0%, and EE lower than 5.6%) could be an effective way to maintain stable digestion and achieve higher methane production (385-627mL/gVS) and shorter digestion retention (196-409h). The CA-CP-EE ratio could be used as an important indicator for digestion performance. To effectively evaluate organic reduction, the concentration and removal efficiency of organic compositions in both solid phases and total FW should be considered. Copyright © 2017. Published by Elsevier Ltd.

Digestion in sea urchin larvae impaired under ocean acidification

NASA Astrophysics Data System (ADS)

Stumpp, Meike; Hu, Marian; Casties, Isabel; Saborowski, Reinhard; Bleich, Markus; Melzner, Frank; Dupont, Sam

2013-12-01

Larval stages are considered as the weakest link when a species is exposed to challenging environmental changes. Reduced rates of growth and development in larval stages of calcifying invertebrates in response to ocean acidification might be caused by energetic limitations. So far no information exists on how ocean acidification affects digestive processes in marine larval stages. Here we reveal alkaline (~pH 9.5) conditions in the stomach of sea urchin larvae. Larvae exposed to decreased seawater pH suffer from a drop in gastric pH, which directly translates into decreased digestive efficiencies and triggers compensatory feeding. These results suggest that larval digestion represents a critical process in the context of ocean acidification, which has been overlooked so far.

Advanced Manufacturing Systems in Food Processing and Packaging Industry

NASA Astrophysics Data System (ADS)

Shafie Sani, Mohd; Aziz, Faieza Abdul

2013-06-01

In this paper, several advanced manufacturing systems in food processing and packaging industry are reviewed, including: biodegradable smart packaging and Nano composites, advanced automation control system consists of fieldbus technology, distributed control system and food safety inspection features. The main purpose of current technology in food processing and packaging industry is discussed due to major concern on efficiency of the plant process, productivity, quality, as well as safety. These application were chosen because they are robust, flexible, reconfigurable, preserve the quality of the food, and efficient.

Process simulation for advanced composites production

DOE Office of Scientific and Technical Information (OSTI.GOV)

Allendorf, M.D.; Ferko, S.M.; Griffiths, S.

1997-04-01

The objective of this project is to improve the efficiency and lower the cost of chemical vapor deposition (CVD) processes used to manufacture advanced ceramics by providing the physical and chemical understanding necessary to optimize and control these processes. Project deliverables include: numerical process models; databases of thermodynamic and kinetic information related to the deposition process; and process sensors and software algorithms that can be used for process control. Target manufacturing techniques include CVD fiber coating technologies (used to deposit interfacial coatings on continuous fiber ceramic preforms), chemical vapor infiltration, thin-film deposition processes used in the glass industry, and coatingmore » techniques used to deposit wear-, abrasion-, and corrosion-resistant coatings for use in the pulp and paper, metals processing, and aluminum industries.« less

Adaptive control of anaerobic digestion processes-a pilot-scale application.

PubMed

Renard, P; Dochain, D; Bastin, G; Naveau, H; Nyns, E J

1988-03-01

A simple adaptive control algorithm, for which theoretical stability and convergence properties had been previously demonstrated, has been successfully implemented on a biomethanation pilot reactor. The methane digester, operated in the CSTR mode was submitted to a shock load, and successfully computer controlled during the subsequent transitory state.

Protein Molecular Structures, Protein SubFractions, and Protein Availability Affected by Heat Processing: A Review

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yu,P.

2007-01-01

The utilization and availability of protein depended on the types of protein and their specific susceptibility to enzymatic hydrolysis (inhibitory activities) in the gastrointestine and was highly associated with protein molecular structures. Studying internal protein structure and protein subfraction profiles leaded to an understanding of the components that make up a whole protein. An understanding of the molecular structure of the whole protein was often vital to understanding its digestive behavior and nutritive value in animals. In this review, recently obtained information on protein molecular structural effects of heat processing was reviewed, in relation to protein characteristics affecting digestive behaviormore » and nutrient utilization and availability. The emphasis of this review was on (1) using the newly advanced synchrotron technology (S-FTIR) as a novel approach to reveal protein molecular chemistry affected by heat processing within intact plant tissues; (2) revealing the effects of heat processing on the profile changes of protein subfractions associated with digestive behaviors and kinetics manipulated by heat processing; (3) prediction of the changes of protein availability and supply after heat processing, using the advanced DVE/OEB and NRC-2001 models, and (4) obtaining information on optimal processing conditions of protein as intestinal protein source to achieve target values for potential high net absorbable protein in the small intestine. The information described in this article may give better insight in the mechanisms involved and the intrinsic protein molecular structural changes occurring upon processing.« less

40 CFR 428.80 - Applicability; description of the wet digestion reclaimed rubber subcategory.

Code of Federal Regulations, 2014 CFR

2014-07-01

... digestion reclaimed rubber subcategory. 428.80 Section 428.80 Protection of Environment ENVIRONMENTAL... CATEGORY Wet Digestion Reclaimed Rubber Subcategory § 428.80 Applicability; description of the wet digestion reclaimed rubber subcategory. The provisions of this subpart are applicable to process waste water...

40 CFR 428.80 - Applicability; description of the wet digestion reclaimed rubber subcategory.

Code of Federal Regulations, 2012 CFR

2012-07-01

... digestion reclaimed rubber subcategory. 428.80 Section 428.80 Protection of Environment ENVIRONMENTAL... CATEGORY Wet Digestion Reclaimed Rubber Subcategory § 428.80 Applicability; description of the wet digestion reclaimed rubber subcategory. The provisions of this subpart are applicable to process waste water...

40 CFR 428.80 - Applicability; description of the wet digestion reclaimed rubber subcategory.

Code of Federal Regulations, 2013 CFR

2013-07-01

... digestion reclaimed rubber subcategory. 428.80 Section 428.80 Protection of Environment ENVIRONMENTAL... CATEGORY Wet Digestion Reclaimed Rubber Subcategory § 428.80 Applicability; description of the wet digestion reclaimed rubber subcategory. The provisions of this subpart are applicable to process waste water...

[Advance in interferogram data processing technique].

PubMed

Jing, Juan-Juan; Xiangli, Bin; Lü, Qun-Bo; Huang, Min; Zhou, Jin-Song

2011-04-01

Fourier transform spectrometry is a type of novel information obtaining technology, which integrated the functions of imaging and spectra, but the data that the instrument acquired is the interference data of the target, which is an intermediate data and couldn't be used directly, so data processing must be adopted for the successful application of the interferometric data In the present paper, data processing techniques are divided into two classes: general-purpose and special-type. First, the advance in universal interferometric data processing technique is introduced, then the special-type interferometric data extracting method and data processing technique is illustrated according to the classification of Fourier transform spectroscopy. Finally, the trends of interferogram data processing technique are discussed.

Anaerobic digestion and co-digestion of slaughterhouse waste (SHW): influence of heat and pressure pre-treatment in biogas yield.

PubMed

Cuetos, M J; Gómez, X; Otero, M; Morán, A

2010-10-01

Mesophilic anaerobic digestion (34+/-1 degrees C) of pre-treated (for 20 min at 133 degrees C, >3 bar) slaughterhouse waste and its co-digestion with the organic fraction of municipal solid waste (OFMSW) have been assessed. Semi-continuously-fed digesters worked with a hydraulic retention time (HRT) of 36 d and organic loading rates (OLR) of 1.2 and 2.6 kg VS(feed)/m(3)d for digestion and co-digestion, respectively, with a previous acclimatization period in all cases. It was not possible to carry out an efficient treatment of hygienized waste, even less so when OFMSW was added as co-substrate. These digesters presented volatile fatty acids (VFA), long chain fatty acids (LCFA) and fats accumulation, leading to instability and inhibition of the degradation process. The aim of applying a heat and pressure pre-treatment to promote splitting of complex lipids and nitrogen-rich waste into simpler and more biodegradable constituents and to enhance biogas production was not successful. These results indicate that the temperature and the high pressure of the pre-treatment applied favoured the formation of compounds that are refractory to anaerobic digestion. The pre-treated slaughterhouse wastes and the final products of these systems were analyzed by FTIR and TGA. These tools verified the existence of complex nitrogen-containing polymers in the final effluents, confirming the formation of refractory compounds during pre-treatment. (c) 2010 Elsevier Ltd. All rights reserved.

Anaerobic Digestion I. Sludge Treatment and Disposal Course #166. Instructor's Guide [and] Student Workbook.

ERIC Educational Resources Information Center

Arasmith, E. E.

This lesson is the first of a two-part series on anaerobic digestion. Topics discussed include the five basic functions of an anaerobic digester, basic theory of the biological processes involved, basic equipment necessary for digestion, and the products of digestion. The lesson includes an instructor's guide and student workbook. The instructor's…

Effect of radiation processing on in vitro protein digestibility and availability of calcium, phosphorus and iron of peanut

NASA Astrophysics Data System (ADS)

Hassan, Amro B.; Diab, Eiman E.; Mahmoud, Nagat S.; Elagib, Randa A. A.; Rushdi, Mohamed A. H.; Osman, Gammaa A. M.

2013-10-01

The effect of gamma irradiation of two peanut cultivars (Sodari and Madani) on protein content, in vitro protein digestibility and availability of calcium, phosphorus and iron was determined. Seeds were treated with gamma irradiation at dose levels of 1.0, 1.5 and 2.0 kGy. Total protein in seeds was not changed significantly by irradiation. However, the in vitro protein digestibility was decreased for both cultivars. In addition, the irradiation also caused an increment on the available calcium, phosphorus and iron for both cultivars. Moreover, radiation processing caused an increment on tannin content of the seeds especially at the dose 2 kGy for both cultivars. Regarding these results, irradiation treatment of peanut up to 2 kGy can be used as an effective alternative method to chemical treatments for insect disinfestation and microbial disinfection.

Molecular motors that digest their track to rectify Brownian motion: processive movement of exonuclease enzymes.

PubMed

Xie, Ping

2009-09-16

A general model is presented for the processive movement of molecular motors such as λ-exonuclease, RecJ and exonuclease I that use digestion of a DNA track to rectify Brownian motion along this track. Using this model, the translocation dynamics of these molecular motors is studied. The sequence-dependent pausing of λ-exonuclease, which results from a site-specific high affinity DNA interaction, is also studied. The theoretical results are consistent with available experimental data. Moreover, the model is used to predict the lifetime distribution and force dependence of these paused states.

Assessment of advanced coal gasification processes

NASA Technical Reports Server (NTRS)

Mccarthy, J.; Ferrall, J.; Charng, T.; Houseman, J.

1981-01-01

A technical assessment of the following advanced coal gasification processes is presented: high throughput gasification (HTG) process; single stage high mass flux (HMF) processes; (CS/R) hydrogasification process; and the catalytic coal gasification (CCG) process. Each process is evaluated for its potential to produce synthetic natural gas from a bituminous coal. Key similarities, differences, strengths, weaknesses, and potential improvements to each process are identified. The HTG and the HMF gasifiers share similarities with respect to: short residence time (SRT), high throughput rate, slagging, and syngas as the initial raw product gas. The CS/R hydrogasifier is also SRT, but is nonslagging and produces a raw gas high in methane content. The CCG gasifier is a long residence time, catalytic, fluidbed reactor producing all of the raw product methane in the gasifier.

Integration of pyrolysis and anaerobic digestion--use of aqueous liquor from digestate pyrolysis for biogas production.

PubMed

Hübner, Tobias; Mumme, Jan

2015-05-01

Anaerobic digestion of aqueous pyrolysis liquor derived from pyrolysis of solid digestate was tested in batch mode using an un-adapted inoculum. Three pyrolysis liquors produced at 330°C, 430°C and 530°C in four COD-based concentrations of 3, 6, 12 and 30 g L(-1) were investigated. The three lower concentrations showed considerable biogas production, whereas the 30 g L(-1) dosage caused process inhibition. The highest methane yield of 199.1±18.5 mL g(COD)(-1) (COD removal: 56.9±5.3%) was observed for the 330°C pyrolysis liquor, followed by the 430°C sample with only slightly lower values. The 530°C sample dropped to a yield of 129.3±19.7 mL g(COD)(-1) (COD removal: 36.9±5.6%). Most VOCs contained in the pyrolysis liquor (i.e. furfural, phenol, catechol, guaiacol, and levoglucosan) were reduced below detection limit (cresol by 10-60%). Consequently, integrated pyrolysis and anaerobic digestion in addition to thermochemical conversion of digestate also promises bioconversion of pyrolysis liquors. Copyright © 2015 Elsevier Ltd. All rights reserved.

Historical Analysis of Portuguese Primary School Textbooks (1920-2005) on the Topic of Digestion

ERIC Educational Resources Information Center

Carvalho, Graca S.; Silva, Rui; Clement, Pierre

2007-01-01

Our previous studies have shown that Portuguese primary school pupils and teachers have three main difficulties in the representation of the digestion process: the sequence of the digestive tract, blood absorption, and the relationship of the digestive function with other human functions. In this study we analysed the topic of digestion in 63…

Immunohistochemical localization of translationally controlled tumor protein in the mouse digestive system

PubMed Central

Sheverdin, Vadim; Jung, Jiwon; Lee, Kyunglim

2013-01-01

Translationally controlled tumor protein (TCTP) is a housekeeping protein, highly conserved among various species. It plays a major role in cell differentiation, growth, proliferation, apoptosis and carcinogenesis. Studies reported so far on TCTP expression in different digestive organs have not led to any understanding of the role of TCTP in digestion, so we localized TCTP in organs of the mouse digestive system employing immunohistochemical techniques. Translationally controlled tumor protein was found expressed in all organs studied: tongue, salivary glands, esophagus, stomach, small and large intestines, liver and pancreas. The expression of TCTP was found to be predominant in epithelia and neurons of myenteric nerve ganglia; high in serous glands (parotid, submandibular, gastric, intestinal crypts, pancreatic acini) and in neurons of myenteric nerve ganglia, and moderate to low in epithelia. In epithelia, expression of TCTP varied depending on its type and location. In enteric neurons, TCTP was predominantly expressed in the processes. Translationally controlled tumor protein expression in the liver followed porto-central gradient with higher expression in pericentral hepatocytes. In the pancreas, TCTP was expressed in both acini and islet cells. Our finding of nearly universal localization and expression of TCTP in mouse digestive organs points to the hitherto unrecognized functional importance of TCTP in the digestive system and suggests the need for further studies of the possible role of TCTP in the proliferation, secretion, absorption and neural regulation of the digestive process and its importance in the physiology and pathology of digestive process. PMID:23834399

Disinhibition of excessive volatile fatty acids to improve the efficiency of autothermal thermophilic aerobic sludge digestion by chemical approach.

PubMed

Jin, Ningben; Jin, Bo; Zhu, Nanwen; Yuan, Haiping; Ruan, Jianbo

2015-01-01

In this study, we explored a chemical approach to eliminate inhibition of excessive volatile fatty acids (VFAs) in autothermal thermophilic aerobic digestion (ATAD). Ferric nitrate, ferric chloride, potassium nitrate and potassium chloride were employed to demonstrate the combined action of ferric ion and nitrate ion. Supplementation of ferric nitrate in the sludge digestion system resulted in reducing the concentration of Total VFAs (TVFA) by round 5000mg/L and more than 2000mg/L of acetic acid at the end of digestion. Lower TVFA concentration contributed to faster sludge stabilization rate and the VS removal of ferric nitrate dosed digester achieved 38.18% after 12days digestion which was 9days in advance compared with the stabilization time of sludge in digester without chemicals addition. Lower concentrations of NH4(+)-N and SCOD in supernatant while higher content of TP in digestion sludge were obtained in digester with ferric nitrate added. Copyright © 2014 Elsevier Ltd. All rights reserved.

Plant Lectins as Medical Tools against Digestive System Cancers.

PubMed

Estrada-Martínez, Laura Elena; Moreno-Celis, Ulisses; Cervantes-Jiménez, Ricardo; Ferriz-Martínez, Roberto Augusto; Blanco-Labra, Alejandro; García-Gasca, Teresa

2017-07-03

Digestive system cancers-those of the esophagus, stomach, small intestine, colon-rectum, liver, and pancreas-are highly related to genetics and lifestyle. Most are considered highly mortal due to the frequency of late diagnosis, usually in advanced stages, caused by the absence of symptoms or masked by other pathologies. Different tools are being investigated in the search of a more precise diagnosis and treatment. Plant lectins have been studied because of their ability to recognize and bind to carbohydrates, exerting a variety of biological activities on animal cells, including anticancer activities. The present report integrates existing information on the activity of plant lectins on various types of digestive system cancers, and surveys the current state of research into their properties for diagnosis and selective treatment.

Plant Lectins as Medical Tools against Digestive System Cancers

PubMed Central

Estrada-Martínez, Laura Elena; Cervantes-Jiménez, Ricardo; Ferriz-Martínez, Roberto Augusto; Blanco-Labra, Alejandro

2017-01-01

Digestive system cancers—those of the esophagus, stomach, small intestine, colon-rectum, liver, and pancreas—are highly related to genetics and lifestyle. Most are considered highly mortal due to the frequency of late diagnosis, usually in advanced stages, caused by the absence of symptoms or masked by other pathologies. Different tools are being investigated in the search of a more precise diagnosis and treatment. Plant lectins have been studied because of their ability to recognize and bind to carbohydrates, exerting a variety of biological activities on animal cells, including anticancer activities. The present report integrates existing information on the activity of plant lectins on various types of digestive system cancers, and surveys the current state of research into their properties for diagnosis and selective treatment. PMID:28671623

Positive Discipline. ERIC Digest.

ERIC Educational Resources Information Center

ERIC Clearinghouse on Elementary and Early Childhood Education, Urbana, IL.

This ERIC Digest suggests methods and language that can be used in handling difficult, but common, situations involving young children. Discussion focuses on: (1) 12 methods of discipline that promote self-worth; (2) the process of creating a positive climate that promotes self-discipline; (3) harmful and negative disciplinary methods; and (4)…

Prediction of in vivo neutral detergent fiber digestibility and digestion rate of potentially digestible neutral detergent fiber: comparison of models.

PubMed

Huhtanen, P; Seppälä, A; Ahvenjärvi, S; Rinne, M

2008-10-01

Eleven 1-pool, seven 2-pool, and three 3-pool models were compared in fitting gas production data and predicting in vivo NDF digestibility and effective first-order digestion rate of potentially digestible NDF (pdNDF). Isolated NDF from 15 grass silages harvested at different stages of maturity was incubated in triplicate in rumen fluid-buffer solution for 72 h to estimate the digestion kinetics from cumulative gas production profiles. In vivo digestibility was estimated by the total fecal collection method in sheep fed at a maintenance level of feeding. The concentration of pdNDF was estimated by a 12-d in situ incubation. The parameter values from gas production profiles and pdNDF were used in a 2-compartment rumen model to predict pdNDF digestibility using 50 h of rumen residence time distributed in a ratio of 0.4:0.6 between the non-escapable and escapable pools. The effective first-order digestion rate was computed both from observed in vivo and model-predicted pdNDF digestibility assuming the passage kinetic model described above. There were marked differences between the models in fitting the gas production data. The fit improved with increasing number of pools, suggesting that silage pdNDF is not a homogenous substrate. Generally, the models predicted in vivo NDF digestibility and digestion rate accurately. However, a good fit of gas production data was not necessarily translated into improved predictions of the in vivo data. The models overestimating the asymptotic gas volumes tended to underestimate the in vivo digestibility. Investigating the time-related residuals during the later phases of fermentation is important when the data are used to estimate the first-order digestion rate of pdNDF. Relatively simple models such as the France model or even a single exponential model with discrete lag period satisfied the minimum criteria for a good model. Further, the comparison of feedstuffs on the basis of parameter values is more unequivocal than in the case

Benefits of supplementing an industrial waste anaerobic digester with energy crops for increased biogas production

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nges, Ivo Achu, E-mail: Nges.Ivo_Achu@biotek.lu.se; Escobar, Federico; Fu Xinmei

2012-01-15

Highlights: Black-Right-Pointing-Pointer This study demonstrates the feasibility of co-digestion food industrial waste with energy crops. Black-Right-Pointing-Pointer Laboratory batch co-digestion led to improved methane yield and carbon to nitrogen ratio as compared to mono-digestion of industrial waste. Black-Right-Pointing-Pointer Co-digestion was also seen as a means of degrading energy crops with nutrients addition as crops are poor in nutrients. Black-Right-Pointing-Pointer Batch co-digestion methane yields were used to predict co-digestion methane yield in full scale operation. Black-Right-Pointing-Pointer It was concluded that co-digestion led an over all economically viable process and ensured a constant supply of feedstock. - Abstract: Currently, there is increasing competitionmore » for waste as feedstock for the growing number of biogas plants. This has led to fluctuation in feedstock supply and biogas plants being operated below maximum capacity. The feasibility of supplementing a protein/lipid-rich industrial waste (pig manure, slaughterhouse waste, food processing and poultry waste) mesophilic anaerobic digester with carbohydrate-rich energy crops (hemp, maize and triticale) was therefore studied in laboratory scale batch and continuous stirred tank reactors (CSTR) with a view to scale-up to a commercial biogas process. Co-digesting industrial waste and crops led to significant improvement in methane yield per ton of feedstock and carbon-to-nitrogen ratio as compared to digestion of the industrial waste alone. Biogas production from crops in combination with industrial waste also avoids the need for micronutrients normally required in crop digestion. The batch co-digestion methane yields were used to predict co-digestion methane yield in full scale operation. This was done based on the ratio of methane yields observed for laboratory batch and CSTR experiments compared to full scale CSTR digestion of industrial waste. The economy of crop

Linking Microbial Community Structure and Function During the Acidified Anaerobic Digestion of Grass

PubMed Central

Joyce, Aoife; Ijaz, Umer Z.; Nzeteu, Corine; Vaughan, Aoife; Shirran, Sally L.; Botting, Catherine H.; Quince, Christopher; O’Flaherty, Vincent; Abram, Florence

2018-01-01

Harvesting valuable bioproducts from various renewable feedstocks is necessary for the critical development of a sustainable bioeconomy. Anaerobic digestion is a well-established technology for the conversion of wastewater and solid feedstocks to energy with the additional potential for production of process intermediates of high market values (e.g., carboxylates). In recent years, first-generation biofuels typically derived from food crops have been widely utilized as a renewable source of energy. The environmental and socioeconomic limitations of such strategy, however, have led to the development of second-generation biofuels utilizing, amongst other feedstocks, lignocellulosic biomass. In this context, the anaerobic digestion of perennial grass holds great promise for the conversion of sustainable renewable feedstock to energy and other process intermediates. The advancement of this technology however, and its implementation for industrial applications, relies on a greater understanding of the microbiome underpinning the process. To this end, microbial communities recovered from replicated anaerobic bioreactors digesting grass were analyzed. The bioreactors leachates were not buffered and acidic pH (between 5.5 and 6.3) prevailed at the time of sampling as a result of microbial activities. Community composition and transcriptionally active taxa were examined using 16S rRNA sequencing and microbial functions were investigated using metaproteomics. Bioreactor fraction, i.e., grass or leachate, was found to be the main discriminator of community analysis across the three molecular level of investigation (DNA, RNA, and proteins). Six taxa, namely Bacteroidia, Betaproteobacteria, Clostridia, Gammaproteobacteria, Methanomicrobia, and Negativicutes accounted for the large majority of the three datasets. The initial stages of grass hydrolysis were carried out by Bacteroidia, Gammaproteobacteria, and Negativicutes in the grass biofilms, in addition to Clostridia in the

Grain source and marginal changes in forage particle size modulate digestive processes and nutrient intake of dairy cows.

PubMed

Nasrollahi, S M; Khorvash, M; Ghorbani, G R; Teimouri-Yansari, A; Zali, A; Zebeli, Q

2012-08-01

This study investigated the effects of, and interactions between, dietary grain source and marginal changes in alfalfa hay (AH) particle size (PS) on digestive processes of dairy cows. A total of eight Holstein dairy cows (175 days in milk) were allocated in a replicated 4 × 4 Latin square design with four 21-day periods. The experiment was a 2 × 2 factorial arrangement with two levels of theoretical PS of AH (fine = 15 mm or long = 30 mm) each combined with two different sources of cereal grains (barley grain alone or barley plus corn grain in a 50 : 50 ratio). Results showed that cows consuming diets supplemented with corn had greater dry matter and nutrient intakes (P < 0.01), independent of forage PS. In addition, the apparent digestibility of fiber fractions was greater for diets supplemented with corn (P = 0.01). The feeding of barley grain-based diets was associated with greater apparent digestibility of non-fiber carbohydrates, and this variable was even greater when long AH was fed (P = 0.04). Moreover, the feeding of long AH resulted in longer time spent eating (P = 0.03) and higher pH (P < 0.01), as well as a tendency for higher acetate-to-propionate ratio in the rumen fluid (P = 0.06) at 3 h post feeding. In conclusion, the results indicated that the marginal increase of PS of AH may prolong eating time and improve rumen fermentation, particularly in diets based on barley grain. Partial substitution of barley grain by corn can improve feed intake and fiber digestibility in mid-lactation dairy cows.

Air Force Academy Aeronautics Digest - Spring/Summer 1982.

DTIC Science & Technology

1983-03-01

Ben Rich, discusses the philosophy of advanced aircraft design and development that has made the "Skunk Works" so successful. Editorial Review by Capt...This Digest has been reviewed and is approved for publication. Thomas E. McCann, Lt. Colonel, USAF Director of Research and Continuing Education... review . Our thanks also to Associate Editor, Martha Arends, and Production Artist, Deborah Ross, of Contract Techical Services, Inc. *The first eight

Review article: fungal microbiota and digestive diseases.

PubMed

Wang, Z K; Yang, Y S; Stefka, A T; Sun, G; Peng, L H

2014-04-01

The role of the fungal microbiota in digestive diseases is poorly defined, but is becoming better understood due to advances in metagenomics. To review the gastrointestinal fungal microbiota and its relationship with digestive diseases. Search of the literature using PubMed and MEDLINE databases. Subject headings including 'fungal-bacterial interactions', 'mycotoxins', 'immunity to fungi', 'fungal infection', 'fungal microbiota', 'mycobiome' and 'digestive diseases' were used. The fungal microbiota is an integral part of the gastrointestinal microecosystem with up to 10(6) microorganisms per gram of faeces. Next-generation sequencing of the fungal 18S rRNA gene has allowed better characterisation of the gastrointestinal mycobiome. Numerous interactions between fungi and bacteria and the complex immune response to gastrointestinal commensal or pathogenic fungi all impact on the pathophysiology of inflammatory bowel disease and other gastrointestinal inflammatory entities such as peptic ulcers. Mycotoxins generated as fungal metabolites contribute to disturbances of gastrointestinal barrier and immune functions and are associated with chronic intestinal inflammatory conditions as well as hepatocellular and oesophagogastric cancer. Systemic and gastrointestinal disease can also lead to secondary fungal infections. Fungal genomic databases and methodologies need to be further developed and will allow a much better understanding of the diversity and function of the mycobiome in gastrointestinal inflammation, tumourigenesis, liver cirrhosis and transplantation, and its alteration as a consequence of antibiotic therapy and chemotherapy. The fungal microbiota and its metabolites impact gastrointestinal function and contribute to the pathogenesis of digestive diseases. Further metagenomic analyses of the gastrointestinal mycobiome in health and disease is needed. © 2014 John Wiley & Sons Ltd.

Assessing the fate of Ascaris suum ova during mesophilic anaerobic digestion.

PubMed

Manser, Nathan D; Wald, Ileana; Ergas, Sarina J; Izurieta, Ricardo; Mihelcic, James R

2015-03-03

There is limited knowledge about the survival of geohelminths, which are soil-transmitted human pathogens, in mesophilic anaerobic digestion processes. This study examined the fate of embryonated and unembryonated Ascaris suum ova in six laboratory-scale mesophilic (35 °C) anaerobic digesters processing swine manure to identify their survival strategies and investigate potential mechanisms to enhance their destruction. There was no significant difference in inactivation of Ascaris suum ova in digesters operated at different solids residence times (SRT) or feeding frequencies. Ova exposed to an anaerobic environment became dormant, or remained unembryonated throughout their residence in the reactors. Approximately 65% of ova were able to retain their viability for up to 16 days, after which the rate of inactivation increased until nearly all ova were nonviable by day 24. In contrast, ova exposed to aerobic conditions did not become dormant and progressed through several developmental stages until day 16, after which nearly all ova were observed to be nonviable. In addition, only 35% of fully developed ova exposed to the anaerobic environment retained their viability by day 16 compared to 65% for dormant ova. Results suggest that some ova are physically destroyed during digestion and ova can be inactivated faster if their development cycle is aerobically triggered before entering the anaerobic digestion process. Results also suggest that transfer of resource recovery technologies such as mesophilic anaerobic digestion to developing world settings must account for local climatic and health conditions so mutually beneficial outcomes can be attained.

Digested disorder

PubMed Central

DeForte, Shelly; Reddy, Krishna D; Uversky, Vladimir N

2013-01-01

The current literature on intrinsically disordered proteins is overwhelming. To keep interested readers up to speed with this literature, we continue a “Digested Disorder” project and represent a series of reader’s digest type articles objectively representing the research papers and reviews on intrinsically disordered proteins. The only 2 criteria for inclusion in this digest are the publication date (a paper should be published within the covered time frame) and topic (a paper should be dedicated to any aspect of protein intrinsic disorder). The current digest issue covers papers published during the period of April, May, and June of 2013. The papers are grouped hierarchically by topics they cover, and for each of the included paper a short description is given on its major findings. PMID:28516028

Effect of biochar and digestate on microbial respiration and pesticide degradation

NASA Astrophysics Data System (ADS)

Mukherjee, Santanu; Tappe, Wolfgang; Hofmann, Diana; Köppchen, Stephan; Disko, Ulrich; Weihermüller, Lutz; Burauel, Peter; Vereecken, Harry

2014-05-01

To overcome the problem of on farm point sources of pollution stemming from improper handling, spillages, and leakages of pesticides during filling and cleaning of spraying equipment, environmental friendly and low cost technology filter systems are currently under development. Based on a laboratory screening approach, where different biomixtures (soil, with biochar and/or digestate) are tested a full scale outdoor system will be developed. Therefore, different fundamental processes like pesticide mineralization, metabolization, sorption-desorption, and transport behavior of three radiolabelled pesticides (Bentazone, Boscalid and Pyrimethanil) will be investigated. Biochar and digestate mixtures with two contrasting soils (sandy and silt loam) had been used as a novel biofilter material for respiration study instead of conventional soil and straw mixtures. To analyze the pesticide degradation potential and to gain information about the temporal evolution of the degradation process of the biochar and digestate soil mixtures microbial respiration was measured over the course of three month. As expected, digestate acts as an easily available C-source leading to highest release of CO2 compared to other biomixtures used. In contrast, the addition of even small amounts (1 %) of biochar caused a profound suppression in the CO2 release from digestate based mixtures. The exact driving mechanism for this suppression can be manifold likes negative priming or chemisorption of CO2 on biochar or NH3 toxicity induced by the large amount of digestate applied in the experiment (30 %) or can be combination of all effects. Surprisingly, a repeated experiment with same but aged digestate did not show such negative priming. On the other hand, the fate of applied organic contaminants to biomixtures depends on several factors like soil properties and climatic conditions as well as biological degradation. To analyze the degradation potential of the different soil/amendment mixtures a

Discovery of digestive enzymes in carnivorous plants with focus on proteases.

PubMed

Ravee, Rishiesvari; Mohd Salleh, Faris 'Imadi; Goh, Hoe-Han

2018-01-01

Carnivorous plants have been fascinating researchers with their unique characters and bioinspired applications. These include medicinal trait of some carnivorous plants with potentials for pharmaceutical industry. This review will cover recent progress based on current studies on digestive enzymes secreted by different genera of carnivorous plants: Drosera (sundews), Dionaea (Venus flytrap) , Nepenthes (tropical pitcher plants), Sarracenia (North American pitcher plants) , Cephalotus (Australian pitcher plants) , Genlisea (corkscrew plants) , and Utricularia (bladderworts). Since the discovery of secreted protease nepenthesin in Nepenthes pitcher, digestive enzymes from carnivorous plants have been the focus of many studies. Recent genomics approaches have accelerated digestive enzyme discovery. Furthermore, the advancement in recombinant technology and protein purification helped in the identification and characterisation of enzymes in carnivorous plants. These different aspects will be described and discussed in this review with focus on the role of secreted plant proteases and their potential industrial applications.

Advanced information processing system for advanced launch system: Hardware technology survey and projections

NASA Technical Reports Server (NTRS)

Cole, Richard

1991-01-01

The major goals of this effort are as follows: (1) to examine technology insertion options to optimize Advanced Information Processing System (AIPS) performance in the Advanced Launch System (ALS) environment; (2) to examine the AIPS concepts to ensure that valuable new technologies are not excluded from the AIPS/ALS implementations; (3) to examine advanced microprocessors applicable to AIPS/ALS, (4) to examine radiation hardening technologies applicable to AIPS/ALS; (5) to reach conclusions on AIPS hardware building blocks implementation technologies; and (6) reach conclusions on appropriate architectural improvements. The hardware building blocks are the Fault-Tolerant Processor, the Input/Output Sequencers (IOS), and the Intercomputer Interface Sequencers (ICIS).

Diets high in resistant starch and arabinoxylan modulate digestion processes and SCFA pool size in the large intestine and faecal microbial composition in pigs.

PubMed

Nielsen, Tina S; Lærke, Helle N; Theil, Peter K; Sørensen, Jens F; Saarinen, Markku; Forssten, Sofia; Knudsen, Knud E Bach

2014-12-14

The effects of a high level of dietary fibre (DF) either as arabinoxylan (AX) or resistant starch (RS) on digestion processes, SCFA concentration and pool size in various intestinal segments and on the microbial composition in the faeces were studied in a model experiment with pigs. A total of thirty female pigs (body weight 63.1 (sem 4.4) kg) were fed a low-DF, high-fat Western-style control diet (WSD), an AX-rich diet (AXD) or a RS-rich diet (RSD) for 3 weeks. Diet significantly affected the digestibility of DM, protein, fat, NSP and NSP components, and the arabinose:xylose ratio, as well as the disappearance of NSP and AX in the large intestine. RS was mainly digested in the caecum. AX was digested at a slower rate than RS. The digesta from AXD-fed pigs passed from the ileum to the distal colon more than twice as fast as those from WSD-fed pigs, with those from RSD-fed pigs being intermediate (P< 0.001). AXD feeding resulted in a higher number of Faecalibacterium prausnitzii, Roseburia intestinalis, Blautia coccoides-Eubacterium rectale, Bifidobacterium spp. and Lactobacillus spp. in the faeces sampled at week 3 of the experimental period (P< 0.05). In the caecum, proximal and mid colon, AXD feeding resulted in a 3- to 5-fold higher pool size of butyrate compared with WSD feeding, with the RSD being intermediate (P <0.001). In conclusion, the RSD and AXD differently affected digestion processes compared with the WSD, and the AXD most efficiently shifted the microbial composition towards butyrogenic species in the faeces and increased the large-intestinal butyrate pool size.

Method of digesting an explosive nitro compound

DOEpatents

Shah, Manish M.

2000-01-01

The present invention is a process wherein bleaching oxidants are used to digest explosive nitro compounds. The process has an excellent reaction rate for digesting explosives and operates under multivariate conditions. Reaction solutions may be aqueous, non-aqueous or a combination thereof, and can also be any pH, but preferably have a pH between 2 and 9. The temperature may be ambient as well as any temperature above which freezing of the solution would occur and below which any degradation of the bleaching oxidant would occur or below which any explosive reaction would be initiated. The pressure may be any pressure, but is preferably ambient or atmospheric, or a pressure above a vapor pressure of the aqueous solution to avoid boiling of the solution. Because the bleaching oxidant molecules are small, much smaller than an enzyme molecule for example, they can penetrate the microstructure of plastic explosives faster. The bleaching oxidants generate reactive hydroxyl radicals, which can destroy other organic contaminants, if necessary, along with digesting the explosive nitro compound.

Digestibility and metabolizable energy values of processed cassava chips for growing and finishing pigs.

PubMed

Lokaewmanee, Kanda; Kanto, Uthai; Juttupornpong, Sukanya; Yamauchi, Koh-en

2011-02-01

Determinations of digestibility of dry matter (DM), digestible energy (DE), and metabolizable energy (ME) in cassava chips with different levels of crude fiber (CF) were measured in growing pigs (20 kg) and finishing pigs (60 kg). The treatments were (1) cassava starch (0% CF), (2) peeled cassava chips (2.5% CF), (3) non-peeled washed cassava chips (3.9% CF), and (4) non-peeled and non-washed cassava chips (5.2% CF). In the growing pigs, peeled cassava chips, non-peeled washed cassava chips, and non-peeled and non-washed cassava chips had DM digestibility of 87.51%, 78.63%, and 73.89%, respectively. Their DE was 3.69, 3.49, and 3.32 Mcal/kg DM, respectively (DE of cassava starch is 3.90 Mcal/kg DM). ME was 3.54, 3.35, and 3.19 Mcal/kg DM, respectively (ME of cassava starch is 3.74 Mcal/kg DM). On the other hand, in the finishing pigs, the digestibility of DM was 89.13%, 80.63%, and 76.13%, respectively. Their DE was 3.72, 3.53, and 3.43 Mcal/kg DM, respectively (DE of cassava starch is 3.91 Mcal/kg DM). ME was 3.57, 3.38, and 3.29 Mcal/kg DM, respectively (ME of cassava starch is 3.75 Mcal/kg DM). These values increased with decreasing CF content, and the peeled cassava chips had the highest values (P < 0.01). These suggest that the digestibility values of DM, DE, and ME of cassava chips is inversely related to the CF content in cassava chips. It is recommended that cassava chips be peeled for better nutrition for growing and finishing pigs.

Digestive morphophysiology of Gryllodes sigillatus (Orthoptera: Gryllidae).

PubMed

Biagio, Fernanda P; Tamaki, Fabio K; Terra, Walter R; Ribeiro, Alberto F

2009-12-01

The evolution of the digestive system in the Order Orthoptera is disclosed from the study of the morphophysiology of the digestive process in its major taxa. This paper deals with a cricket representing the less known suborder Ensifera. Most amylase and trypsin activities occur in crop and caeca, respectively. Maltase and aminopeptidase are found in soluble and membrane-bound forms in caeca, with aminopeptidase also occurring in ventriculus. Amaranth was orally fed to Gryllodes sigillatus adults or injected into their haemolymph. The experiments were performed with starving and feeding insects with identical results. Following feeding of the dye the luminal side of the most anterior ventriculus (and in lesser amounts the midgut caeca) became heavily stained. In injected insects, the haemal side of the most posterior ventriculus was stained. This suggested that the anterior ventriculus is the main site of water absorption (the caeca is a secondary one), whereas the posterior ventriculus secretes water into the gut. Thus, a putative counter-current flux of fluid from posterior to anterior ventriculus may propel digestive enzyme recycling. This was confirmed by the finding that digestive enzymes are excreted at a low rate. The fine structure of midgut caeca and ventriculus cells revealed that they have morphological features that may be related to their involvement in secretion (movement from cell to lumen) and absorption (movement from lumen to cell) of fluids. Furthermore, morphological data showed that both merocrine and apocrine secretory mechanisms occur in midgut cells. The results showed that cricket digestion differs from that in grasshopper in having: (1) more membrane-bound digestive enzymes; (2) protein digestion slightly displaced toward the ventriculus; (3) midgut fluxes, and hence digestive enzyme recycling, in both starved and fed insects.

Interfacial & colloidal aspects of lipid digestion.

PubMed

Wilde, P J; Chu, B S

2011-06-09

Amongst the main issues challenging the food manufacturing sector, health and nutrition are becoming increasingly important. Global concerns such as obesity, the ageing population and food security will have to be addressed. Food security is not just about assuring food supply, but is also about optimising nutritional delivery from the food that is available [1]. Therefore one challenge is to optimise the health benefits from the lipids and lipid soluble nutrients. Colloid scientists have an affinity for lipids because they are water insoluble, however this presents a challenge to the digestive system, which has to convert them to structures that are less insoluble so they are available for uptake. Despite this, the human digestive system is remarkably effective at digesting and absorbing most lipids. This is primarily driven through maximising energy intake, as lipids possess the highest calorific value, which was a survival trait to survive times of famine, but is now an underlying cause of obesity in developed countries with high food availability. The critical region here is the lipid-water interface, where the key reactions take place to solubilise lipids and lipid soluble nutrients. Digestive lipases have to adsorb to the oil water interface in order to hydrolyse triacylglycerols into fatty acids and mono glycerides, which accumulate at the interface [2], and inhibit lipase activity. Pancreatic lipase, which is responsible for the majority of lipid hydrolysis, also requires the action of bile salts and colipase to function effectively. Bile salts both aid the adsorption of co-lipase and lipase, and help solubilise the lipolysis products which have accumulated at the interface, into mixed micelles composing bile salts and a range of other lipids, to facilitate transport to the gut mucosal surface prior to uptake and absorption. The process can be affected by the lipid type, as shorter chain, fatty acids are more easily absorbed, whereas the uptake of longer

Flexible digestion strategies and trace metal assimilation in marine bivalves

USGS Publications Warehouse

Decho, Alan W.; Luoma, Samuel N.

1996-01-01

Pulse-chase experiments show that two marine bivalves take optimal advantage of different types of particulate food by varying food retention time in a flexible two-phase digestive system. For example, carbon is efficiently assimilated from bacteria by subjecting nearly all the ingested bacteria to prolonged digestion. Prolonging digestion also enhances assimilation of metals, many of which are toxic in minute quantities if they are biologically available. Detritus-feeding aquatic organisms have always lived in environments naturally rich in particle-reactive metals. We suggest that avoiding excess assimilation of metals could be a factor in the evolution of digestion strategies. We tested that suggestion by studying digestion of particles containing different Cr concentrations. We show that bivalves are capable of modifying the digestive processing of food to reduce exposure to high, biologically available, Cr concentrations. The evolution of a mechanism in some species to avoid high concentrations of metals in food could influence how effects of modern metal pollution are manifested in marine ecosystems.

Composting of the solid fraction of digestate derived from pig slurry: Biological processes and compost properties.

PubMed

Tambone, Fulvia; Terruzzi, Laura; Scaglia, Barbara; Adani, Fabrizio

2015-01-01

The aim of this paper was to assess the characteristics of the solid fractions (SF) obtained by mechanical separation of digestate, their compostability and compost quality. To do so, the SF of digestates obtained from anaerobic digestion of pig slurry, energy crops and agro-industrial residues were sampled in five plants located in Northern Italy. Results obtained indicated that anaerobic digestion by itself promoted the high biological stability of biomasses with a Potential Dynamic Respiration Index (PDRI) close to 1000 mgO2 kg V S(-1)h(-1). Subsequent composting of digestates, with an added bulking agent, did not give remarkably different results, and led only to a slight modification of the characteristics of the initial non-composted mixtures; the composts obtained fully respected the legal limits for high quality compost. Chemical studies of organic matter composition of the biomasses by using CP MAS (13)C NMR, indicated that the compost was composed of a high relative content of O-alkyl-C (71.47% of total C) (cellulose and hemicelluloses) and a low alkyl-C (12.42%) (i.e. volatile fatty acids, steroid-like molecules, aliphatic biopolymers and proteins). Copyright © 2014 Elsevier Ltd. All rights reserved.

Microbial community redundancy in anaerobic digestion drives process recovery after salinity exposure.

PubMed

De Vrieze, Jo; Christiaens, Marlies E R; Walraedt, Diego; Devooght, Arno; Ijaz, Umer Zeeshan; Boon, Nico

2017-03-15

Anaerobic digestion of high-salinity wastewaters often results in process inhibition due to the susceptibility of the methanogenic archaea. The ability of the microbial community to deal with increased salinity levels is of high importance to ensure process perseverance or recovery after failure. The exact strategy of the microbial community to ensure process endurance is, however, often unknown. In this study, we investigated how the microbial community is able to recover process performance following a disturbance through the application of high-salinity molasses wastewater. After a stable start-up, methane production quickly decreased from 625 ± 17 to 232 ± 35 mL CH 4 L -1 d -1 with a simultaneous accumulation in volatile fatty acids up to 20.5 ± 1.4 g COD L -1 , indicating severe process disturbance. A shift in feedstock from molasses wastewater to waste activated sludge resulted in complete process recovery. However, the bacterial and archaeal communities did not return to their original composition as before the disturbance, despite similar process conditions. Microbial community diversity was recovered to similar levels as before disturbance, which indicates that the metabolic potential of the community was maintained. A mild increase in ammonia concentration after process recovery did not influence methane production, indicating a well-balanced microbial community. Hence, given the change in community composition following recovery after salinity disturbance, it can be assumed that microbial community redundancy was the major strategy to ensure the continuation of methane production, without loss of functionality or metabolic flexibility. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Digested disorder

PubMed Central

Reddy, Krishna D; DeForte, Shelly; Uversky, Vladimir N

2014-01-01

The current literature on intrinsically disordered proteins grows fast. To keep interested readers up to speed with this literature, we continue a “Digested Disorder” project and represent a new issue of reader’s digest of the research papers and reviews on intrinsically disordered proteins. The only 2 criteria for inclusion in this digest are the publication date (a paper should be published within the covered time frame) and topic (a paper should be dedicated to any aspect of protein intrinsic disorder). The current digest issue covers papers published during the third quarter of 2013; i.e., during the period of June, July, and September of 2013. Similar to previous issues, the papers are grouped hierarchically by topics they cover, and for each of the included paper a short description is given on its major findings. PMID:28232877

Advanced Research Deposition System (ARDS) for processing CdTe solar cells

NASA Astrophysics Data System (ADS)

Barricklow, Keegan Corey

CdTe solar cells have been commercialized at the Gigawatt/year level. The development of volume manufacturing processes for next generation CdTe photovoltaics (PV) with higher efficiencies requires research systems with flexibility, scalability, repeatability and automation. The Advanced Research Deposition Systems (ARDS) developed by the Materials Engineering Laboratory (MEL) provides such a platform for the investigation of materials and manufacturing processes necessary to produce the next generation of CdTe PV. Limited by previous research systems, the ARDS was developed to provide process and hardware flexibility, accommodating advanced processing techniques, and capable of producing device quality films. The ARDS is a unique, in-line process tool with nine processing stations. The system was designed, built and assembled at the Materials Engineering Laboratory. Final assembly, startup, characterization and process development are the focus of this research. Many technical challenges encountered during the startup of the ARDS were addressed in this research. In this study, several hardware modifications needed for the reliable operation of the ARDS were designed, constructed and successfully incorporated into the ARDS. The effect of process condition on film properties for each process step was quantified. Process development to achieve 12% efficient baseline solar cell required investigation of discrete processing steps, troubleshooting process variation, and developing performance correlations. Subsequent to this research, many advances have been demonstrated with the ARDS. The ARDS consistently produces devices of 12% +/-.5% by the process of record (POR). The champion cell produced to date utilizing the ARDS has an efficiency of 16.2% on low cost commercial sodalime glass and utilizes advanced films. The ARDS has enabled investigation of advanced concepts for processing CdTe devices including, Plasma Cleaning, Plasma Enhanced Closed Space Sublimation

In vitro dynamic model simulating the digestive tract of 6-month-old infants

PubMed Central

Gallo, Marianna; Tornatore, Fabio; Frasso, Annalisa; Saccone, Giulia; Budelli, Andrea; Barone, Maria V.

2017-01-01

Background In vivo assays cannot always be conducted because of ethical reasons, technical constraints or costs, but a better understanding of the digestive process, especially in infants, could be of great help in preventing food-related pathologies and in developing new formulas with health benefits. In this context, in vitro dynamic systems to simulate human digestion and, in particular, infant digestion could become increasingly valuable. Objective To simulate the digestive process through the use of a dynamic model of the infant gastroenteric apparatus to study the digestibility of starch-based infant foods. Design Using M.I.D.A (Model of an Infant Digestive Apparatus), the oral, gastric and intestinal digestibility of two starch-based products were measured: 1) rice starch mixed with distilled water and treated using two different sterilization methods (the classical method with a holding temperature of 121°C for 37 min and the HTST method with a holding temperature of 137°C for 70 sec) and 2) a rice cream with (premium product) or without (basic product) an aliquot of rice flour fermented by Lactobacillus paracasei CBA L74. After the digestion the foods were analyzed for the starch concentration, the amount of D-glucose released and the percentage of hydrolyzed starch. Results An in vitro dynamic system, which was referred to as M.I.D.A., was obtained. Using this system, the starch digestion occurred only during the oral and intestinal phase, as expected. The D-glucose released during the intestinal phase was different between the classical and HTST methods (0.795 grams for the HTST versus 0.512 for the classical product). The same analysis was performed for the basic and premium products. In this case, the premium product had a significant difference in terms of the starch hydrolysis percentage during the entire process. Conclusions The M.I.D.A. system was able to digest simple starches and a more complex food in the correct compartments. In this study

In vitro dynamic model simulating the digestive tract of 6-month-old infants.

PubMed

Passannanti, Francesca; Nigro, Federica; Gallo, Marianna; Tornatore, Fabio; Frasso, Annalisa; Saccone, Giulia; Budelli, Andrea; Barone, Maria V; Nigro, Roberto

2017-01-01

In vivo assays cannot always be conducted because of ethical reasons, technical constraints or costs, but a better understanding of the digestive process, especially in infants, could be of great help in preventing food-related pathologies and in developing new formulas with health benefits. In this context, in vitro dynamic systems to simulate human digestion and, in particular, infant digestion could become increasingly valuable. To simulate the digestive process through the use of a dynamic model of the infant gastroenteric apparatus to study the digestibility of starch-based infant foods. Using M.I.D.A (Model of an Infant Digestive Apparatus), the oral, gastric and intestinal digestibility of two starch-based products were measured: 1) rice starch mixed with distilled water and treated using two different sterilization methods (the classical method with a holding temperature of 121°C for 37 min and the HTST method with a holding temperature of 137°C for 70 sec) and 2) a rice cream with (premium product) or without (basic product) an aliquot of rice flour fermented by Lactobacillus paracasei CBA L74. After the digestion the foods were analyzed for the starch concentration, the amount of D-glucose released and the percentage of hydrolyzed starch. An in vitro dynamic system, which was referred to as M.I.D.A., was obtained. Using this system, the starch digestion occurred only during the oral and intestinal phase, as expected. The D-glucose released during the intestinal phase was different between the classical and HTST methods (0.795 grams for the HTST versus 0.512 for the classical product). The same analysis was performed for the basic and premium products. In this case, the premium product had a significant difference in terms of the starch hydrolysis percentage during the entire process. The M.I.D.A. system was able to digest simple starches and a more complex food in the correct compartments. In this study, better digestibility of the premium product was

Immunohistochemical localization of translationally controlled tumor protein in the mouse digestive system.

PubMed

Sheverdin, Vadim; Jung, Jiwon; Lee, Kyunglim

2013-09-01

Translationally controlled tumor protein (TCTP) is a housekeeping protein, highly conserved among various species. It plays a major role in cell differentiation, growth, proliferation, apoptosis and carcinogenesis. Studies reported so far on TCTP expression in different digestive organs have not led to any understanding of the role of TCTP in digestion, so we localized TCTP in organs of the mouse digestive system employing immunohistochemical techniques. Translationally controlled tumor protein was found expressed in all organs studied: tongue, salivary glands, esophagus, stomach, small and large intestines, liver and pancreas. The expression of TCTP was found to be predominant in epithelia and neurons of myenteric nerve ganglia; high in serous glands (parotid, submandibular, gastric, intestinal crypts, pancreatic acini) and in neurons of myenteric nerve ganglia, and moderate to low in epithelia. In epithelia, expression of TCTP varied depending on its type and location. In enteric neurons, TCTP was predominantly expressed in the processes. Translationally controlled tumor protein expression in the liver followed porto-central gradient with higher expression in pericentral hepatocytes. In the pancreas, TCTP was expressed in both acini and islet cells. Our finding of nearly universal localization and expression of TCTP in mouse digestive organs points to the hitherto unrecognized functional importance of TCTP in the digestive system and suggests the need for further studies of the possible role of TCTP in the proliferation, secretion, absorption and neural regulation of the digestive process and its importance in the physiology and pathology of digestive process. © 2013 Anatomical Society.

Advances in the study of berberine and its derivatives: a focus on anti-inflammatory and anti-tumor effects in the digestive system.

PubMed

Zou, Kun; Li, Zhao; Zhang, Yong; Zhang, Hao-Yue; Li, Bo; Zhu, Wei-Liang; Shi, Ji-Ye; Jia, Qi; Li, Yi-Ming

2017-02-01

It has been widely recognized that inflammation, particularly chronic inflammation, can increase the risk of cancer and that the simultaneous treatment of inflammation and cancer may produce excellent therapeutic effects. Berberine, an alkaloid isolated from Rhizoma coptidis, has broad applications, particularly as an antibacterial agent in the clinic with a long history. Over the past decade, many reports have demonstrated that this natural product and its derivatives have high activity against both cancer and inflammation. In this review, we summarize the advances in studing berberine and its derivatives as anti-inflammatory and anti-tumor agents in the digestive system; we also discuss their structure-activity relationship. These data should be useful for the development of this natural product as novel anticancer drugs with anti-inflammation activity.

Occurrence and Fate of Trace Contaminants during Aerobic and Anaerobic Sludge Digestion and Dewatering.

PubMed

Guerra, Paula; Kleywegt, Sonya; Payne, Michael; Svoboda, M Lewina; Lee, Hing-Biu; Reiner, Eric; Kolic, Terry; Metcalfe, Chris; Smyth, Shirley Anne

2015-07-01

Digestion of municipal wastewater biosolids is a necessary prerequisite to their beneficial use in land application, in order to protect public health and the receiving environment. In this study, 13 pharmaceuticals and personal care products (PPCPs), 11 musks, and 17 polybrominated diphenyl ethers were analyzed in 84 samples including primary sludge, waste activated sludge, digested biosolids, dewatered biosolids, and dewatering centrate or filtrate collected from five wastewater treatment plants with aerobic or anaerobic digestion. Aerobic digestion processes were sampled during both warm and cold temperatures to analyze seasonal differences. Among the studied compounds, triclosan, triclocarban, galaxolide, and BDE-209 were the substances most frequently detected under different treatment processes at levels up to 30,000 ng/g dry weight. Comparing aerobic and anaerobic digestion, it was observed that the levels of certain PPCPs and musks were significantly higher in anaerobically digested biosolids, relative to the residues from aerobic digestion. Therefore, aerobic digestion has the potential advantage of reducing levels of PPCPs and musks. On the other hand, anaerobic digestion has the advantage of recovering energy from the biosolids in the form of combustible gases while retaining the nutrient and soil conditioning value of this resource. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Anaerobic co-digestion of commercial food waste and dairy manure: Characterizing biochemical parameters and synergistic effects.

PubMed

Ebner, Jacqueline H; Labatut, Rodrigo A; Lodge, Jeffrey S; Williamson, Anahita A; Trabold, Thomas A

2016-06-01

Anaerobic digestion of commercial food waste is a promising alternative to landfilling commercial food waste. This study characterized 11 types of commercial food wastes and 12 co-digestion blends. Bio-methane potential, biodegradable fraction, and apparent first-order hydrolysis rate coefficients were reported based upon biochemical methane potential (BMP) assays. Food waste bio-methane potentials ranged from 165 to 496 mL CH4/g VS. Substrates high in lipids or readily degradable carbohydrates showed the highest methane production. Average bio-methane potential observed for co-digested substrates was -5% to +20% that of the bio-methane potential of the individual substrates weighted by VS content. Apparent hydrolysis rate coefficients ranged from 0.19d(-1) to 0.65d(-1). Co-digested substrates showed an accelerated apparent hydrolysis rate relative to the weighted average of individual substrate rates. These results provide a database of key bio-digestion parameters to advance modeling and utilization of commercial food waste in anaerobic digestion. Copyright © 2016 Elsevier Ltd. All rights reserved.

Participation in the Center for Advanced Processing and Packaging Studies

DTIC Science & Technology

2009-11-24

University, the University ofCalifomia, Davis, and North Carolina State University to assist in advancing food processing and packaging technology and...University, the University of California, Davis, and North Carolina State University to assist in advancing food processing and packaging technology and...amyloliquefaciens, spore inactivation, FT-IR spectroscopy, infrared 11 spectroscopy 12 13 14 15 16 17 Department of Food Science and Technology

Genetic Analysis of Digestive Physiology Using Fluorescent Phospholipid Reporters

NASA Astrophysics Data System (ADS)

Farber, Steven A.; Pack, Michael; Ho, Shiu-Ying; Johnson, Iain D.; Wagner, Daniel S.; Dosch, Roland; Mullins, Mary C.; Hendrickson, H. Stewart; Hendrickson, Elizabeth K.; Halpern, Marnie E.

2001-05-01

Zebrafish are a valuable model for mammalian lipid metabolism; larvae process lipids similarly through the intestine and hepatobiliary system and respond to drugs that block cholesterol synthesis in humans. After ingestion of fluorescently quenched phospholipids, endogenous lipase activity and rapid transport of cleavage products results in intense gall bladder fluorescence. Genetic screening identifies zebrafish mutants, such as fat free, that show normal digestive organ morphology but severely reduced phospholipid and cholesterol processing. Thus, fluorescent lipids provide a sensitive readout of lipid metabolism and are a powerful tool for identifying genes that mediate vertebrate digestive physiology.

Advances in biologically inspired on/near sensor processing

NASA Astrophysics Data System (ADS)

McCarley, Paul L.

1999-07-01

As electro-optic sensors increase in size and frame rate, the data transfer and digital processing resource requirements also increase. In many missions, the spatial area of interest is but a small fraction of the available field of view. Choosing the right region of interest, however, is a challenge and still requires an enormous amount of downstream digital processing resources. In order to filter this ever-increasing amount of data, we look at how nature solves the problem. The Advanced Guidance Division of the Munitions Directorate, Air Force Research Laboratory at Elgin AFB, Florida, has been pursuing research in the are of advanced sensor and image processing concepts based on biologically inspired sensory information processing. A summary of two 'neuromorphic' processing efforts will be presented along with a seeker system concept utilizing this innovative technology. The Neuroseek program is developing a 256 X 256 2-color dual band IRFPA coupled to an optimized silicon CMOS read-out and processing integrated circuit that provides simultaneous full-frame imaging in MWIR/LWIR wavebands along with built-in biologically inspired sensor image processing functions. Concepts and requirements for future such efforts will also be discussed.

FEU Technology Digest No. 3.

ERIC Educational Resources Information Center

Further Education Unit, London (England).

This digest contains four articles about technology and education in Britain. "The Development of an 'Additional Skills' Training Programme" (Peter Riley) details the organization and progress of a collaborative effort between Blackpool Processing Company and Flyde College's Additional Skills training program, a solution to achieving the…

Single-phase and two-phase anaerobic digestion of fruit and vegetable waste: Comparison of start-up, reactor stability and process performance

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ganesh, Rangaraj; Torrijos, Michel, E-mail: michel.torrijos@supagro.inra.fr; Sousbie, Philippe

Highlights: • Single-phase and two-phase systems were compared for fruit and vegetable waste digestion. • Single-phase digestion produced a methane yield of 0.45 m{sup 3} CH{sub 4}/kg VS and 83% VS removal. • Substrate solubilization was high in acidification conditions at 7.0 kg VS/m{sup 3} d and pH 5.5–6.2. • Energy yield was lower by 33% for two-phase system compared to the single-phase system. • Simple and straight-forward operation favored single phase process over two-phase process. - Abstract: Single-phase and two-phase digestion of fruit and vegetable waste were studied to compare reactor start-up, reactor stability and performance (methane yield, volatilemore » solids reduction and energy yield). The single-phase reactor (SPR) was a conventional reactor operated at a low loading rate (maximum of 3.5 kg VS/m{sup 3} d), while the two-phase system consisted of an acidification reactor (TPAR) and a methanogenic reactor (TPMR). The TPAR was inoculated with methanogenic sludge similar to the SPR, but was operated with step-wise increase in the loading rate and with total recirculation of reactor solids to convert it into acidification sludge. Before each feeding, part of the sludge from TPAR was centrifuged, the centrifuge liquid (solubilized products) was fed to the TPMR and centrifuged solids were recycled back to the reactor. Single-phase digestion produced a methane yield of 0.45 m{sup 3} CH{sub 4}/kg VS fed and VS removal of 83%. The TPAR shifted to acidification mode at an OLR of 10.0 kg VS/m{sup 3} d and then achieved stable performance at 7.0 kg VS/m{sup 3} d and pH 5.5–6.2, with very high substrate solubilization rate and a methane yield of 0.30 m{sup 3} CH{sub 4}/kg COD fed. The two-phase process was capable of high VS reduction, but material and energy balance showed that the single-phase process was superior in terms of volumetric methane production and energy yield by 33%. The lower energy yield of the two-phase system was due to the

Horse manure as feedstock for anaerobic digestion.

PubMed

Hadin, Sa; Eriksson, Ola

2016-10-01

Horse keeping is of great economic, social and environmental benefit for society, but causes environmental impacts throughout the whole chain from feed production to manure treatment. According to national statistics, the number of horses in Sweden is continually increasing and is currently approximately 360,000. This in turn leads to increasing amounts of horse manure that have to be managed and treated. Current practices could cause local and global environmental impacts due to poor performance or lack of proper management. Horse manure with its content of nutrients and organic material can however contribute to fertilisation of arable land and recovery of renewable energy following anaerobic digestion. At present anaerobic digestion of horse manure is not a common treatment. In this paper the potential for producing biogas and biofertiliser from horse manure is analysed based on a thorough literature review in combination with mathematical modelling and simulations. Anaerobic digestion was chosen as it has a high degree of resource conservation, both in terms of energy (biogas) and nutrients (digestate). Important factors regarding manure characteristics and operating factors in the biogas plant are identified. Two crucial factors are the type and amount of bedding material used, which has strong implications for feedstock characteristics, and the type of digestion method applied (dry or wet process). Straw and waste paper are identified as the best materials in an energy point of view. While the specific methane yield decreases with a high amount of bedding, the bedding material still makes a positive contribution to the energy balance. Thermophilic digestion increases the methane generation rate and yield, compared with mesophilic digestion, but the total effect is negligible. Copyright © 2016. Published by Elsevier Ltd.

Digestion of Protein in Premature and Term Infants

PubMed Central

Dallas, David C; Underwood, Mark A; Zivkovic, Angela M.; German, J. Bruce

2014-01-01

Premature birth rates and premature infant morbidity remain discouragingly high. Improving nourishment for these infants is the key for accelerating their development and decreasing disease risk. Dietary protein is essential for growth and development of infants. Studies on protein nourishment for premature infants have focused on protein requirements for catch-up growth, nitrogen balance, and digestive protease concentrations and activities. However, little is known about the processes and products of protein digestion in the premature infant. This review briefly summarizes the protein requirements of term and preterm infants, and the protein content of milk from women delivering preterm and at term. An in-depth review is presented of the current knowledge of term and preterm infant dietary protein digestion, including human milk protease and anti-protease concentrations; neonatal intestinal pH, and enzyme activities and concentrations; and protein fermentation by intestinal bacteria. The advantages and disadvantages of incomplete protein digestion as well as factors that increase resistance to proteolysis of particular proteins are discussed. In order to better understand protein digestion in preterm and term infants, future studies should examine protein and peptide fragment products of digestion in saliva, gastric, intestinal and fecal samples, as well as the effects of the gut micro biome on protein degradation. The confluence of new mass spectrometry technology and new bioinformatics programs will now allow thorough identification of the array of peptides produced in the infant as they are digested. PMID:24744976

Bioethanol fermentation as alternative valorization route of agricultural digestate according to a biorefinery approach.

PubMed

Sambusiti, C; Monlau, F; Barakat, A

2016-07-01

This study investigates the feasibility of producing bioethanol from solid digestate after a mechanical fractionation (i.e. centrifugal milling), in order to improve the energy recovery from agricultural wastes and the sustainability of anaerobic digestion plants. A bioethanol yield of 37gkg(-1)TS was evaluated for the solid digestate fraction. Mass and energetic balances were performed and compared between two scenarios: (A) one-stage bioethanol fermentation and (B) two-stage anaerobic digestion-bioethanol fermentation, in order to evaluate the feasibility and the advantages of the two-stage process. Results revealed that, compared to the one-stage process, the dual anaerobic digestion-bioethanol process permitted: (i) to diversify biofuels production; (ii) to provide the thermal energy sufficient for drying digestate (13,351kWhthday(-1)), for the subsequent milling step; (iii) to reduce the electric energy requirement for the milling step (from 23,880 to 3580kWhelday(-1)); (iv) to produce extra electrical energy of 8483kWhelday(-1); (v) to improve the reduction of waste streams generated (from 13% to 54% of organic matter removal). Copyright © 2016. Published by Elsevier Ltd.

Effects of freezing, freeze drying and convective drying on in vitro gastric digestion of apples.

PubMed

Dalmau, Maria Esperanza; Bornhorst, Gail M; Eim, Valeria; Rosselló, Carmen; Simal, Susana

2017-01-15

The influence of processing (freezing at -196°C in liquid N2, FN sample; freeze-drying at -50°C and 30Pa, FD sample; and convective drying at 60°C and 2m/s, CD sample) on apple (var. Granny Smith) behavior during in vitro gastric digestion was investigated. Dried apples (FD and CD samples) were rehydrated prior to digestion. Changes in carbohydrate composition, moisture, soluble solids, acidity, total polyphenol content (TPC), and antioxidant activity (AA) of apple samples were measured at different times during digestion. Processing resulted in disruption of the cellular structure during digestion, as observed by scanning electron microscopy, light microscopy, and changes in carbohydrate composition. Moisture content increased (6-11% dmo), while soluble solids (55-78% dmo), acidity (44-72% dmo), total polyphenol content (30-61% dmo), and antioxidant activity (41-87%) decreased in all samples after digestion. Mathematical models (Weibull and exponential models) were used to better evaluate the influence of processing on apple behavior during gastric digestion. Copyright © 2016 Elsevier Ltd. All rights reserved.

Anaerobic digestion of dairy cattle manure autoheated by aerobic pretreatment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Achkari-Begdouri, A.

1989-01-01

A novel way to heat anaerobic digesters was investigated. Dairy cattle manure was autoheated by an aerobic pretreatment process and then fed to the anaerobic digester. Important physical properties of the dairy cattle manure were determined. These included bulk density, specific heat, thermal conductivity and the rheological properties; consistency coefficient, behavior index and apparent viscosity. These parameters were used to calculate the overall heat transfer coefficients, and to estimate the heat losses from the aerobic reactor to the outside environment. The total energy balance of the aerobic treatment system was then established. An optimization study of the main parameters influencingmore » the autoheating process showed that the total solids, the air flow rate and the stirring speed for operation of the aerobic pretreatment should be approximately 7%, 70 L/H and 1,400 rpm respectively. Temperatures as high as 65C were reached in 40 hours of aerobic treatment. At the above recommended levels of total solids, the air flow rate and the stirring speed, there was little difference in the energy requirements for heating the influent by aeration and heating the influent by a conventional heating system. In addition to the temperature increase, the aerobic pretreatment assisted in balancing the anaerobic digestion process and increased the methanogenesis of the dairy cattle manure. Despite the 8% decomposition of organic matter that occurred during the aerobic pretreatment process, methane production of the digester started with the aerobically heated manure was significantly higher (at least 20% higher) than of the digester started with conventionally heated manure. The aerobic system successfully autoheated the dairy cattle manure with an energy cost equal to that of conventionally heated influent.« less

Model calibration and validation for OFMSW and sewage sludge co-digestion reactors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Esposito, G., E-mail: giovanni.esposito@unicas.it; Frunzo, L., E-mail: luigi.frunzo@unina.it; Panico, A., E-mail: anpanico@unina.it

2011-12-15

Highlights: > Disintegration is the limiting step of the anaerobic co-digestion process. > Disintegration kinetic constant does not depend on the waste particle size. > Disintegration kinetic constant depends only on the waste nature and composition. > The model calibration can be performed on organic waste of any particle size. - Abstract: A mathematical model has recently been proposed by the authors to simulate the biochemical processes that prevail in a co-digestion reactor fed with sewage sludge and the organic fraction of municipal solid waste. This model is based on the Anaerobic Digestion Model no. 1 of the International Watermore » Association, which has been extended to include the co-digestion processes, using surface-based kinetics to model the organic waste disintegration and conversion to carbohydrates, proteins and lipids. When organic waste solids are present in the reactor influent, the disintegration process is the rate-limiting step of the overall co-digestion process. The main advantage of the proposed modeling approach is that the kinetic constant of such a process does not depend on the waste particle size distribution (PSD) and rather depends only on the nature and composition of the waste particles. The model calibration aimed to assess the kinetic constant of the disintegration process can therefore be conducted using organic waste samples of any PSD, and the resulting value will be suitable for all the organic wastes of the same nature as the investigated samples, independently of their PSD. This assumption was proven in this study by biomethane potential experiments that were conducted on organic waste samples with different particle sizes. The results of these experiments were used to calibrate and validate the mathematical model, resulting in a good agreement between the simulated and observed data for any investigated particle size of the solid waste. This study confirms the strength of the proposed model and calibration procedure

Fate of four phthalate plasticizers under various wastewater treatment processes.

PubMed

Armstrong, Dana L; Rice, Clifford P; Ramirez, Mark; Torrents, Alba

2018-05-18

The fate of four phthalate plasticizers during wastewater treatment processes at six different wastewater treatment plants (WWTPs) was investigated. Concentrations of benzyl butyl phthalate (BBP), di(2-ethylhexyl) phthalate (DEHP), diisononyl phthalate (DiNP), and diisodecyl phthalate (DiDP) were determined prior to either aerobic or anaerobic (conventional and advanced) treatment, after treatment, and in final, dewatered solids. Despite their elevated use worldwide, the fate of DiNP and DiDP during wastewater treatment have not been well characterized. DEHP was readily degraded during aerobic treatments while anaerobic digestion resulted in either no significant change in concentrations or an increase in concentration, in the case of more advanced anaerobic processes (thermal hydrolysis pretreatment and a two-phase acid/gas process). Impacts of the various treatment systems on DiNP, DiDP, and BBP concentrations were more varied - anaerobic digestion led to significant decreases, increases, or no significant change for these compounds, depending on the treatment facility, while aerobic treatment was generally effective at degrading the compounds. Additionally, thermal hydrolysis pretreatment of sludge prior to anaerobic digestion resulted in increases in DiNP, DiDP, and BBP concentrations. The predicted environmental concentrations for all four compounds in soils after a single biosolids application were calculated and the risk quotients for DEHP in soils were determined. The estimated toxicity risk for DEHP in soils treated with a single application of sludge from any of the six studied WWTPs is lower than the level of concern for acute and chronic risk, as defined by the US EPA.

Comparison of amino acid digestibility of feedstuffs determined with the precision-fed cecectomized rooster assay and the standardized ileal amino acid digestibility assay.

PubMed

Kim, E J; Utterback, P L; Applegate, T J; Parsons, C M

2011-11-01

The objective of this study was to evaluate and compare amino acid digestibility of several feedstuffs using 2 commonly accepted methods: the precision-fed cecectomized rooster assay (PFR) and the standardized ileal amino acid assay (SIAAD). Six corn, 6 corn distillers dried grains with or without solubles (DDGS/DDG), one wet distillers grains, one condensed solubles, 2 meat and bone meal (MBM) and a poultry byproduct meal were evaluated. Due to insufficient amounts, the wet distillers grains and condensed solubles were only evaluated in roosters. Standardized amino acid digestibility varied among the feed ingredients and among samples of the same ingredient for both methods. For corn, there were generally no differences in amino acid digestibility between the 2 methods. When differences did occur, there was no consistent pattern among the individual amino acids and methods. Standardized amino acid digestibility was not different between the 2 methods for 4 of the DDG samples; however, the PFR yielded higher digestibility values for a high protein DDG and a conventionally processed DDGS. The PFR yielded higher amino acid digestibility values than the SIAAD for several amino acids in 1 MBM and the poultry byproduct meal, but it yielded lower digestibility values for the other MBM. Overall, there were no consistent differences between methods for amino acid digestibility values. In conclusion, the PFR and SIAAD methods are acceptable for determining amino acid digestibility. However, these procedures do not always yield similar results for all feedstuffs evaluated. Thus, further studies are needed to understand the underlying causes in this variability.

Sequential Anaerobic/Aerobic Digestion for Enhanced Carbon/Nitrogen Removal and Cake Odor Reduction.

PubMed

Ahmad, Muneer; Denee, Marco Abel; Jiang, Hao; Eskicioglu, Cigdem; Kadota, Paul; Gregonia, Theresa

2016-12-01

  Anaerobic digestion (AD) has been proven to be an effective process for the treatment of wastewater sludge. However, it produces high levels of ammonia in the digester effluent, which may jeopardize meeting stringent nutrient discharge limits. In this study, the effect of a sequential anaerobic/aerobic (AN/AERO) digestion and a single-stage conventional AN digestion (as control) was investigated on mixed (primary + secondary) sludge generated by the Annacis Island wastewater treatment plant (WWTP) (BC, Canada). An overall sludge retention time (SRT) of 22.5 days under three different scenarios was chosen based on the current operational SRT of the digesters at the Annacis Island WWTP. The steady state results have shown that sequential AN/AERO digestion configurations achieved up to 11% higher volatile solids (VS) removal and 72% lower ammonia generation over single-stage conventional AN digestion. Furthermore, sequential AN/AERO system also showed enhanced dewaterability, improved fecal coliform destruction and reduced digested cake odors over control digesters.

Digested disorder: Quarterly intrinsic disorder digest (April-May-June, 2013).

PubMed

DeForte, Shelly; Reddy, Krishna D; Uversky, Vladimir N

2013-01-01

The current literature on intrinsically disordered proteins is overwhelming. To keep interested readers up to speed with this literature, we continue a "Digested Disorder" project and represent a series of reader's digest type articles objectively representing the research papers and reviews on intrinsically disordered proteins. The only 2 criteria for inclusion in this digest are the publication date (a paper should be published within the covered time frame) and topic (a paper should be dedicated to any aspect of protein intrinsic disorder). The current digest issue covers papers published during the period of April, May, and June of 2013. The papers are grouped hierarchically by topics they cover, and for each of the included paper a short description is given on its major findings.

Impact of a multicarbohydrase containing α-galactosidase and xylanase on ileal digestible energy, crude protein digestibility, and ileal amino acid digestibility in broiler chickens.

PubMed

Jasek, A; Latham, R E; Mañón, A; Llamas-Moya, S; Adhikari, R; Poureslami, R; Lee, J T

2018-06-08

Exogenous enzymatic supplementation of poultry feeds, including α-galactosidase and xylanase, has been shown to increase metabolically available energy, although little information has been published on the impact on amino acid digestibility. An experiment was conducted to investigate a multicarbohydrase containing α-galactosidase and xylanase on amino acid digestibility, ileal digestible energy (IDE), and CP in male broiler chicks. The experiment was a 2 × 2 (diet × enzyme) factorial arrangement with 15 replicates of 8 male broilers per replicate raised for 21 d in a battery setting. The 2 dietary treatments included a positive control (PC) and a negative control (NC) diet formulated to contain 2.5% less calculated AME and digestible amino acids. Each of these diets was fed with and without enzyme. Broilers were fed a starter diet from 0-14 d (crumble) and a grower from 14-21 d (pellet). Birds were sampled on day 21 to determine ileal amino acid digestibility, IDE, and CP digestibility. Titanium dioxide (TiO2) was used as an indigestible marker for the determination of digestibility coefficients. Total ileal amino acid digestibility was increased (P = 0.008) by 3.80% with the inclusion of enzyme. Methionine and lysine digestibility was improved (P < 0.05) with the inclusion of enzyme by 3.37% and 2.61%, respectively. Enzyme inclusion increased (P = 0.001) cysteine digestibility by 9.3%. Diet-influenced ileal amino acid digestibility with tryptophan, threonine, isoleucine, and valine digestibility being increased (P < 0.05) in the PC when compared to the NC. IDE was decreased (P = 0.037) in broilers fed the NC diet by 100 kcal/kg feed when compared to broilers fed the PC diet. Enzyme inclusion increased (P = 0.047) IDE value by 90 kcal/kg. Crude protein digestibility was not influenced by diet; however, similar improvements in CP digestibility with enzyme inclusion were observed as with energy. These data support the benefits of a multicarbohydrase containing �

Bioaugmentation of anaerobic sludge digestion with iron-reducing bacteria: process and microbial responses to variations in hydraulic retention time.

PubMed

Baek, Gahyun; Kim, Jaai; Shin, Seung Gu; Lee, Changsoo

2016-01-01

Although anaerobic digestion (AD) is a widely used option to manage waste activated sludge (WAS), there are some drawbacks related to its slow reaction rate and low energy productivity. This study examined an anaerobic WAS digester, augmented with an iron-reducing microbial consortium, relative to changes in microbial community structure and process performance at decreasing hydraulic retention times (HRTs) of 20 to 10 days. The enhanced methanation performance (approximately 40 % increase in methane yield) by the bioaugmentation was sustained until the HRT was decreased to 12.5 days, under Fe(3+)-rich conditions (ferric oxyhydroxide, 20 mM Fe). Enhanced iron-reducing activity was evidenced by the increased Fe(2+) to total Fe ratio maintained above 50 % during the stable operational phases. A further decrease in HRT to 10 days resulted in a significant performance deterioration, along with a drop in the Fe(2+) to total Fe ratio to <35 %, after four turnovers of operation. Prevailing existence of putative iron-reducing bacteria (IRBs) was identified by denaturing gradient gel electrophoresis (DGGE), with Spirochaetaceae- and Thauera-related organisms being dominant members, and clear dominance shifts among them with respect to decrease in HRT were observed. Lowering HRT led to evident shifts in bacterial community structure likely associated with washout of IRBs, leading to decreases in iron respiration activity and AD performance at a lower HRT. The bacterial community structure shifted dynamically over phases, and the community transitions correlated well with the changes in process performance. Overall, the combined biostimulation and bioaugmentation investigated in this study proved effective for enhanced methane recovery from anaerobic WAS digestion, which suggests an interesting potential for high-rate AD.

Influence of fluid dynamics on anaerobic digestion of food waste for biogas production.

PubMed

Wang, Fengping; Zhang, Cunsheng; Huo, Shuhao

2017-05-01

To enhance the stability and efficiency of an anaerobic process, the influences of fluid dynamics on the performance of anaerobic digestion and sludge granulation were investigated using computational fluid dynamics (CFD). Four different propeller speeds (20, 60, 100, 140 r/min) were adopted for anaerobic digestion of food waste in a 30 L continuously stirred tank reactor (CSTR). Experimental results indicated that the methane yield increased with increasing the propeller speed within the experimental range. Results from CFD simulation and sludge granulation showed that the optimum propeller speed for anaerobic digestion was 100 r/min. Lower propeller speed (20 r/min) inhibited mass transfer and resulted in the failure of anaerobic digestion, while higher propeller speed (140 r/min) would lead to higher energy loss and system instability. Under this condition, anaerobic digestion could work effectively with higher efficiency of mass transfer which facilitated sludge granulation and biogas production. The corresponding mean liquid velocity and shear strain rate were 0.082 m/s and 10.48 s -1 , respectively. Moreover, compact granular sludge could be formed, with lower energy consumption. CFD was successfully used to study the influence of fluid dynamics on the anaerobic digestion process. The key parameters of the optimum mixing condition for anaerobic digestion of food waste in a 30 L CSTR including liquid velocity and shear strain rate were obtained using CFD, which were of paramount significance for the scale-up of the bioreactor. This study provided a new way for the optimization and scale-up of the anaerobic digestion process in CSTR based on the fluid dynamics analysis.

Alkaline treatment of high-solids sludge and its application to anaerobic digestion.

PubMed

Li, Chenchen; Li, Huan; Zhang, Yuyao

2015-01-01

High-solids anaerobic digestion is a promising new process for sludge reduction and bioenergy recovery, requiring smaller digestion tanks and less energy for heating, but a longer digestion time, than traditional low-solids anaerobic digestion. To accelerate this process, alkaline sludge disintegration was tested as a pretreatment method for anaerobic digestion of high-solids sludge. The results showed that alkaline treatment effectively disintegrated both low-solids sludge and high-solids sludge, and treatment duration of 30 min was the most efficient. The relation between sludge disintegration degree and NaOH dose can be described by a transmutative power function model. At NaOH dose lower than 0.2 mol/L, sludge disintegration degree remained virtually unchanged when sludge total solids (TS) content increased from 2.0 to 11.0%, and decreased only slightly when sludge TS increased to 14.2%. Although high-solids sludge required a slightly higher molarity of NaOH to reach the same disintegration level of low-solids sludge, the required mass of NaOH actually decreased due to sludge thickening. From the view of NaOH consumption, sludge TS of 8-12% and a NaOH dose of 0.05 mol/L were optimum conditions for alkaline pretreatment, which resulted in a slight increase in accumulative biogas yield, but a decrease by 24-29% in digestion time during the subsequent anaerobic digestion.

Calcium phosphates recovery from digester supernatant by fast precipitation and recrystallization

NASA Astrophysics Data System (ADS)

Vasenko, Liubov; Qu, Haiyan

2018-01-01

Conditional solubility of dicalcium phosphate dihydrate (DCPD) and hydroxyapatite (HAp) in digester supernatant was determined as a function of pH and was compared to its conditional solubility in distilled water. Conditional solubility of both substances in digester supernatant at pH >5-6 was higher than their conditional solubility in pure water due to the presence of impurities, and this influence is more significant for HAp. Amorphous CaP was precipitated through a fast precipitation process from digester supernatant with initial total phosphate concentration 0.008 mol/L and 0.015 mol/L and Ca/P ratios 2 and 5. The amorphous CaP can be subsequently recrystallized into crystalline CaP. Obtained amorphous products have Ca/P ratio > 1, which allow performing the recrystallization process without further Ca dosing into the system. Batch recrystallization of the amorphous products resulted in crystallization of HAp, DCPD or their mixture depending on the conditions of the process. Maximum achieved P-recovery was 69.5%. The increase of phosphate concentration and the addition of seeding decreased the yield of the process but promoted crystallization of DCPD. The increase of Ca/P ratio had a positive effect on the total P-recovery. Compared with the direct batch crystallization of CaP from digester supernatant, the two-step process with fast precipitation and recrystallization significantly improved the color of the obtained products.

Long non-coding RNA PVT1: Emerging biomarker in digestive system cancer.

PubMed

Zhou, Dan-Dan; Liu, Xiu-Fen; Lu, Cheng-Wei; Pant, Om Prakash; Liu, Xiao-Dong

2017-12-01

The digestive system cancers are leading cause of cancer-related death worldwide, and have high risks of morbidity and mortality. More and more long non-coding RNAs (lncRNAs) have been studied to be abnormally expressed in cancers and play a key role in the process of digestive system tumour progression. Plasmacytoma variant translocation 1 (PVT1) seems fairly novel. Since 1984, PVT1 was identified to be an activator of MYC in mice. Its role in human tumour initiation and progression has long been a subject of interest. The expression of PVT1 is elevated in digestive system cancers and correlates with poor prognosis. In this review, we illustrate the various functions of PVT1 during the different stages in the complex process of digestive system tumours (including oesophageal cancer, gastric cancer, colorectal cancer, hepatocellular carcinoma and pancreatic cancer). The growing evidence shows the involvement of PVT1 in both proliferation and differentiation process in addition to its involvement in epithelial to mesenchymal transition (EMT). These findings lead us to conclude that PVT1 promotes proliferation, survival, invasion, metastasis and drug resistance in digestive system cancer cells. We will also discuss PVT1's potential in diagnosis and treatment target of digestive system cancer. There was a great probability PVT1 could be a novel biomarker in screening tumours, prognosis biomarkers and future targeted therapy to improve the survival rate in cancer patients. © 2017 John Wiley & Sons Ltd.

Digested disorder

PubMed Central

Uversky, Vladimir N

2013-01-01

The current literature on intrinsically disordered proteins is blooming. A simple PubMed search for “intrinsically disordered protein OR natively unfolded protein” returns about 1,800 hits (as of June 17, 2013), with many papers published quite recently. To keep interested readers up to speed with this literature, we are starting a “Digested Disorder” project, which will encompass a series of reader’s digest type of publications aiming at the objective representation of the research papers and reviews on intrinsically disordered proteins. The only two criteria for inclusion in this digest are the publication date (a paper should be published within the covered time frame) and topic (a paper should be dedicated to any aspect of protein intrinsic disorder). The current digest covers papers published during the period of January, February and March of 2013. The papers are grouped hierarchically by topics they cover, and for each of the included paper a short description is given on its major findings. PMID:28516015

Blending protein separation and peptide analysis through real-time proteolytic digestion.

PubMed

Slysz, Gordon W; Schriemer, David C

2005-03-15

Typical liquid- or gel-based protein separations require enzymatic digestion as an important first step in generating protein identifications. Traditional protocols involve long-term proteolytic digestion of the separated protein, often leading to sample loss and reduced sensitivity. Previously, we presented a rapid method of proteolytic digestion that showed excellent digestion of resistant and low concentrations of protein without requiring reduction and alkylation. Here, we demonstrate on-line, real-time tryptic digestion in conjunction with reversed-phase protein separation. The studies were aimed at optimizing pH and ionic strength and the size of the digestion element, to produce maximal protein digestion with minimal effects on chromatographic integrity. Upon establishing optimal conditions, the digestion element was attached downstream from a capillary C4 reversed-phase column. A four-protein mixture was processed through the combined system, and the resulting peptides were analyzed on-line by electrospray mass spectrometry. Extracted ion chromatograms for protein chromatography based on peptide elution were generated. These were shown to emulate ion chromatograms produced in a subsequent run without the digestion element, based on protein elution. The methodology will enable rapid and sensitive analysis of liquid-based protein separations using the power of bottom-up proteomics methodologies.

Effluent composition prediction of a two-stage anaerobic digestion process: machine learning and stoichiometry techniques.

PubMed

Alejo, Luz; Atkinson, John; Guzmán-Fierro, Víctor; Roeckel, Marlene

2018-05-16

Computational self-adapting methods (Support Vector Machines, SVM) are compared with an analytical method in effluent composition prediction of a two-stage anaerobic digestion (AD) process. Experimental data for the AD of poultry manure were used. The analytical method considers the protein as the only source of ammonia production in AD after degradation. Total ammonia nitrogen (TAN), total solids (TS), chemical oxygen demand (COD), and total volatile solids (TVS) were measured in the influent and effluent of the process. The TAN concentration in the effluent was predicted, this being the most inhibiting and polluting compound in AD. Despite the limited data available, the SVM-based model outperformed the analytical method for the TAN prediction, achieving a relative average error of 15.2% against 43% for the analytical method. Moreover, SVM showed higher prediction accuracy in comparison with Artificial Neural Networks. This result reveals the future promise of SVM for prediction in non-linear and dynamic AD processes. Graphical abstract ᅟ.

Investigations into Improving Dewaterability at a Bio-P/Anaerobic Digestion Plant.

PubMed

Alm, Rebecca; Sealock, Adam W; Nollet, Yabing; Sprouse, George

2016-11-01

  Metropolitan Council Environmental Services has observed poorer than expected dewatering performance at its Empire Plant. This plant has both anaerobic digestion and enhanced biological phosphorus removal in its treatment train. A research program using pilot-scale anaerobic digesters investigated potential solutions to the plant's poor dewaterability. The dewaterability goal was to increase the cake solids from 12% total solids (TS) to 16% TS or higher. This research investigated 20 different reactor conditions including chemical, feed sludge, and digested sludge treatments. At the pilot scale, unaerated storage of waste activated sludge prior to thickening and addition of ferric chloride to digestion was found to achieve dewatered cake solids of nearly 17% TS with the added benefit of reducing polymer demand. Issues including the amount of chemical required and the resulting volatile solids destruction influence the viability of the process change, so a full-scale pilot and financial analysis is recommended before making permanent process changes.

[Occupational digestive diseases in chemical industry workers of West Siberia].

PubMed

Pomytkina, T E; Pershin, A N

2010-01-01

The high incidence of chronic digestive diseases is recorded in chemical industry workers exposed to the isolated action of noxious substances. The aim of the investigation was to make a hygienic assessment of the risk for occupational digestive diseases in chemical industry workers exposed to a combination of noxious drugs. The working conditions and the prevalence of digestive diseases were studied in 4120 workers engaged in chemical and auxiliary processes. Under the isolated action of noxious substances, the workers had an average of 35% increase in the incidence of digestive diseases than unexposed ones (p < 0.05). Under the combined action of hazardous substances, the incidence of digestive diseases was 1.7-fold greater (p < 0.05) than in the unexposed subjects and 1.2-fold greater in those under isolated action. The odd ratio and relative risk for digestive diseases in the workers exposed to a combination of noxious substances were 4.0-11.1 and 3.5-10.7 times higher, respectively (p < 0.05) than in the unexposed subjects.

Anaerobic co-digestion of coffee husks and microalgal biomass after thermal hydrolysis.

PubMed

Passos, Fabiana; Cordeiro, Paulo Henrique Miranda; Baeta, Bruno Eduardo Lobo; de Aquino, Sergio Francisco; Perez-Elvira, Sara Isabel

2018-04-01

Residual coffee husks after seed processing may be better profited if bioconverted into energy through anaerobic digestion. This process may be improved by implementing a pretreatment step and by co-digesting the coffee husks with a more liquid biomass. In this context, this study aimed at evaluating the anaerobic co-digestion of coffee husks with microalgal biomass. For this, both substrates were pretreated separately and in a mixture for attaining 15% of total solids (TS), which was demonstrated to be the minimum solid content for pretreatment of coffee husks. The results showed that the anaerobic co-digestion presented a synergistic effect, leading to 17% higher methane yield compared to the theoretical value of both substrates biodegraded separately. Furthermore, thermal hydrolysis pretreatment increased coffee husks anaerobic biodegradability. For co-digestion trials, the highest values were reached for pretreatment at 120 °C for 60 min, which led to 196 mLCH 4 /gVS and maximum methane production rate of 0.38 d -1 . Copyright © 2017 Elsevier Ltd. All rights reserved.

Demonstration-scale evaluation of a novel high-solids anaerobic digestion process for converting organic wastes to fuel gas and compost.

PubMed

Rivard, C J; Duff, B W; Dickow, J H; Wiles, C C; Nagle, N J; Gaddy, J L; Clausen, E C

1998-01-01

Early evaluations of the bioconversion potential for combined wastes such as tuna sludge and sorted municipal solid waste (MSW) were conducted at laboratory scale and compared conventional low-solids, stirred-tank anaerobic systems with the novel, high-solids anaerobic digester (HSAD) design. Enhanced feedstock conversion rates and yields were determined for the HSAD system. In addition, the HSAD system demonstrated superior resiliency to process failure. Utilizing relatively dry feedstocks, the HSAD system is approximately one-tenth the size of conventional low-solids systems. In addition, the HSAD system is capable of organic loading rates (OLRs) on the order of 20-25 g volatile solids per liter digester volume per d (gVS/L/d), roughly 4-5 times those of conventional systems. Current efforts involve developing a demonstration-scale (pilot-scale) HSAD system. A two-ton/d plant has been constructed in Stanton, CA and is currently in the commissioning/startup phase. The purposes of the project are to verify laboratory- and intermediate-scale process performance; test the performance of large-scale prototype mechanical systems; demonstrate the long-term reliability of the process; and generate the process and economic data required for the design, financing, and construction of full-scale commercial systems. This study presents conformational fermentation data obtained at intermediate-scale and a snapshot of the pilot-scale project.

Digested disorder: Quarterly intrinsic disorder digest (July-August-September, 2013).

PubMed

Reddy, Krishna D; DeForte, Shelly; Uversky, Vladimir N

2014-01-01

The current literature on intrinsically disordered proteins grows fast. To keep interested readers up to speed with this literature, we continue a "Digested Disorder" project and represent a new issue of reader's digest of the research papers and reviews on intrinsically disordered proteins. The only 2 criteria for inclusion in this digest are the publication date (a paper should be published within the covered time frame) and topic (a paper should be dedicated to any aspect of protein intrinsic disorder). The current digest issue covers papers published during the third quarter of 2013; i.e., during the period of June, July, and September of 2013. Similar to previous issues, the papers are grouped hierarchically by topics they cover, and for each of the included paper a short description is given on its major findings.

Analysis on carbon dioxide emission reduction during the anaerobic synergetic digestion technology of sludge and kitchen waste: Taking kitchen waste synergetic digestion project in Zhenjiang as an example.

PubMed

Guo, Qia; Dai, Xiaohu

2017-11-01

With the popularization of municipal sewage treatment facilities, the improvement of sewage treatment efficiency and the deepening degree of sewage treatment, the sludge production of sewage plant has been sharply increased. Carbon emission during the process of municipal sewage treatment and disposal has become one of the important sources of greenhouse gases that cause greenhouse effect. How to reduce carbon dioxide emissions during sewage treatment and disposal process is of great significance for reducing air pollution. Kitchen waste and excess sludge, as two important organic wastes, once uses anaerobic synergetic digestion technology in the treatment process can on the one hand, avoid instability of sludge individual anaerobic digestion, improve sludge degradation rate and marsh gas production rate, and on the other hand, help increase the reduction of carbon dioxide emissions to a great extent. The paper uses material balance method, analyzes and calculates the carbon dioxide emissions from kitchen waste and sludge disposed by the anaerobic synergetic digestion technology, compares the anaerobic synergetic digestion technology with traditional sludge sanitary landfill technology and works out the carbon dioxide emission reductions after synergetic digestion. It takes the kitchen waste and sludge synergetic digestion engineering project of Zhenjiang city in Jiangsu province as an example, makes material balance analysis using concrete data and works out the carbon dioxide daily emission reductions. The paper analyzes the actual situation of emission reduction by comparing the data, and found that the synergetic digestion of kitchen waste and sludge can effectively reduce the carbon dioxide emission, and the reduction is obvious especially compared with that of sludge sanitary landfill, which has a certain effect on whether to promote the use of the technology. Copyright © 2017 Elsevier Ltd. All rights reserved.

Practical Advances in Petroleum Processing

NASA Astrophysics Data System (ADS)