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Influence of Polyphosphate Hydrolysis on the Degradation of Volatile Fatty Acids (VFAs) in Anaerobic Digestion
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作者 Ikechukwu Maxwell Onoh Gordian Onyebuchukwu Mbah Albert Chibuzo Agulanna 《Advances in Chemical Engineering and Science》 2017年第4期439-449,共11页
The degradation rate of Volatile Fatty Acids (VFAs) produced predominantly in the acidogenesis stage is a key process parameter to be optimised to ensure a successful Anaerobic digestion (AD). Thermodynamically, the o... The degradation rate of Volatile Fatty Acids (VFAs) produced predominantly in the acidogenesis stage is a key process parameter to be optimised to ensure a successful Anaerobic digestion (AD). Thermodynamically, the oxidation of the VFAs are energetically unfavourable, and as such external energy source apart from the energy derived from the hydrolysis of Adenosine Triphosphate (ATP) is needed for the initial activation of the VFAs, initial growth of the methanogens in AD process and improved degradation rate of the VFAs. Thus, this research investigated the influence of polyphosphate hydrolysis on the degradation rate of the VFAs at high concentration. Sodium-propionate, Sodium-butyrate and Sodium-acetate salts were added at the start of experiments in order to increase the concentration of the VFAs. The polyphosphate salts used were;Na-hexametaphosphate, Na-tripolyphosphate and potassium pyrophosphate. The control experiment was polyphosphate free and three process parameters (degradation rate, cumulative biogas production and specific methane content) of anaerobic digestion were investigated. The experiments were carried out at a mesophilic temperature of 37.5°C for 41 days. The results of the investigation showed that the treated reactors with the polyphosphate salt solution in low concentration performed better than the reactors with high concentration of the polyphosphate salts solution. All the treated reactors with poly-P salts performed better than reactor Nr-9 (control experiment), but reactor Nr-1 was outstanding with an improved degradation rate of 47%, cumulative biogas production of 21% and specific methane content of 23%. 展开更多
关键词 volatile fatty acids (vfas) POLYPHOSPHATE SALTS Anaerobic DIGESTION BIOENERGETICS Syntrophic DEGRADATION
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Volatile fatty acids carbon source for biological denitrification 被引量:7
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作者 Xu Yatong (Centre of International Research for Water and Environment, Lyonnaise des Eaux,France) 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1996年第3期257-268,共12页
In the suspended sludge system, when pH and temperature were suitable and carbon source was not limited, the denitrification and C-uptake rate followed a zero-order reaction. Mixed VFA C-source had higher denitrificat... In the suspended sludge system, when pH and temperature were suitable and carbon source was not limited, the denitrification and C-uptake rate followed a zero-order reaction. Mixed VFA C-source had higher denitrification rate than single VFA C-source consisting of them. When VFA were used as carbon source, consumed carbon quantity for denitrification was closed to 1. 07 mg VFA-C/mg NO-N. About 20% of the applied C/N was used for assimilative purposes. As rising up influent C/N by increasing the C load ,the sludge yield YN increased. The part of carbon consumption increased and the effluent oxidized nitrogen decreased. At pH 7. 5, 25℃ and sludge yield 0.72 mg VSS/mg NO-N, the calculated influent VFA-C /NO critical value was 1. 43 for complete denitrification. 展开更多
关键词 biological denitrification suspended sludge volatile fatty acids (vfa) nitrate NITRITE C/N ratio.
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Impacts of the unsaturation degree of long-chain fatty acids on the volatile fatty acid profiles of rumen microbial fermentation in goats in vitro 被引量:3
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作者 GAO Jian WANG Meng-zhi +3 位作者 JING Yu-jia SUN Xue-zhao WU Tian-yi SHI Liang-feng 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第12期2827-2833,共7页
This study investigated the impacts of the degree of unsaturation (unsaturity) of long-chain fatty acids on volatile fatty acid (VFA) profiles of rumen fermentation in vitro. Six types of long-chain fatty acids, i... This study investigated the impacts of the degree of unsaturation (unsaturity) of long-chain fatty acids on volatile fatty acid (VFA) profiles of rumen fermentation in vitro. Six types of long-chain fatty acids, including stearic acid (C18:0, control group), oleic acid (C18:1, n-9), linoleic acid (C18:2, n-6), a-linolenic acid (C18:3, n-3), arachidonic acid (C20:4, n-6) and eicosapentaenoic acid (C20:5, n-3), were tested. Rumen fluid from three goats fitted with ruminal fistulae was used as inoculum and the inclusion rate of long-chain fatty acid was at 3% (w/w) of substrate. Samples were taken for VFA analysis at 0, 3, 6, 9, 12, 18 and 24 h of incubation, respectively. The analysis showed that there were significant differences in the total VFA among treatments, sampling time points, and treatment×time point interactions (P〈0.01). a-Linolenic acid had the highest total VFA (P〈0.01) among different long-chain fatty acids tested. The molar proportion of acetate in total VFA significantly differed among treatments (P〈0.01) and sampling time points (P〈0.01), but not treatment×time point interactions (P〉0.05). In contrast, the molar proportion of propionate did not differ among treatments during the whole incubation (P〉0.05). However, for butyrate molar proportions, significant differences were found not only among sampling time points but also among treatments and treatment×time point interactions (P〈0.01), with eicosapentaenoic acid having the highest value (P〈0.01). Additionally, no statistically significant differences were found in the acetate to propionate ratios among treatments groups (P〉0.05), even the treatments stearic acid and a-linolenic acid were numerically higher than the others. The inclusion of 3% long-chain unsaturated fatty acids differing in the degree of unsaturation brought out a significant quadratic regression relation between the total VFA concentration and the double bond number of fatty acid. In conclusion, the a-linolenic acid with 3 double bonds appeared better for improving rumen microbial fermentation and the total VFA concentration. 展开更多
关键词 volatile fatty acid unsaturation degree long-chain fatty acid in vitro fermentation
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Characteristics of physico-chemical properties, volatile compounds and free fatty acid profiles of commercial set-type Turkish yoghurts 被引量:1
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作者 Zehra Güler Young W. Park 《Open Journal of Animal Sciences》 2011年第1期1-8,共8页
Ten most popular brands of commercial Turkish set-type yoghurts were collected from local retail outlets in Hatay, Turkey for two separate periods, and analyzed for basic nutrients, physico-chemical properties, volati... Ten most popular brands of commercial Turkish set-type yoghurts were collected from local retail outlets in Hatay, Turkey for two separate periods, and analyzed for basic nutrients, physico-chemical properties, volatile aroma compounds and free fatty acid profiles to compare their differences among the yoghurt products. The results showed that there were significant differences (P<0.05, 0.01, or 0.001) and variations in physico-chemical indices, volatile aroma compounds and volatile free fatty acid profiles among the yoghurt brands, which ultimately influence the flavor quality of the product. Acetaldehyde was predominant volatile compound in yoghurts, which followed by acetone, acetoin, diacetyl and ethanol. The level of diacetly was inversely related to titratable acidity, acetaldehyde and ethanoic acid. From ketones with high carbones 2-undecanone and 2-pentadecanone were higher than 2-butanone, 2-nanonane and 2-tridecanone. These ketones are related to fat content of yoghurt. Among short chain free fatty acids, ethanoic (acetic) acid was the most abundant in yoghurts, followed by hexanoic, octanoic and butanoic acids. These differences in detected chemical compositions of volatile compounds and free fatty acids would be applicable to predict flavor, nutritional value, quality control or shelf-life of the commmercial set-type Turkish yoghurts. 展开更多
关键词 TURKISH YOGHURT free fatty acidS volatile compounds PHYSICO-CHEMICAL properties
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Effects of Ultrasonic and Acid Pretreatment on Food Waste Disintegration and Volatile Fatty Acid Production
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作者 Qinglian Wu Wanqian Guo +3 位作者 Shanshan Yang Haichao Luo Simai Peng Nanqi Ren 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2015年第3期1-6,共6页
This study aims at investigating the effects of ultrasonic and acid pretreatment on food waste( FW)disintegration and volatile fatty acid( VFA) production. Single-factor experiments are carried out to obtain optimal c... This study aims at investigating the effects of ultrasonic and acid pretreatment on food waste( FW)disintegration and volatile fatty acid( VFA) production. Single-factor experiments are carried out to obtain optimal conditions of individual ultrasonic and acid pretreatment,and response surface method( RSM) is applied to optimize the conditions of the combination of ultrasonic and acid( UA) pretreatment. Results show that the optimal acid,ultrasonic and UA pretreatments conditions are individual pH 2,individual ultrasonic energy density of 1. 0 W / mL and the combination of ultrasonic energy density1. 11 W / mL and pH 1. 43,respectively. Correspondingly,the maximum disintegration degrees( DD) of 46. 90%,57. 38% and68. 83%are obtained by acid,ultrasonic and UA pretreatments,respectively. After optimizing pretreatment conditions,batch experiments are operated to produce VFA from raw and pretreated FW under anaerobic fermentation process. Both the maximum VFA production( 976. 17 mg COD / gV S) and VFA / SCOD( 72. 89%) are obtained with ultrasonic pretreatment, followed by UA pretreatment, non-pretreatment and acid pretreatment,respectively. This observation demonstrates that a higher acidity on acid and UA pretreatments inhibits the generation of VFA. Results suggest that ultrasonic pretreatment is preferable to promote the disintegration degree of FW and VFA production. 展开更多
关键词 food waste(FW) ultrasonic and acid pretreatment response surface method(RSM) anaerobic fermentation volatile fatty acid(vfa)
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Understanding changes in volatile compounds and fatty acids of Jincheng orange peel oil at different growth stages using GC-MS
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作者 XIE Jiao CAO Qi +2 位作者 WANG Wen-jun ZHANG Hong-yan DENG Bing 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第7期2282-2294,共13页
Jincheng orange(Citrus sinensis Osbeck)is widely grown in Chongqing,China,and is commonly consumed because of its characteristic aroma contributed by the presence of diverse volatile compounds.The changes in aroma dur... Jincheng orange(Citrus sinensis Osbeck)is widely grown in Chongqing,China,and is commonly consumed because of its characteristic aroma contributed by the presence of diverse volatile compounds.The changes in aroma during the development and maturation of fruit are indicators for ripening and harvest time.However,the influence of growth stages on the volatile compounds in Jincheng orange remains unclear.In addition,volatiles originate from fatty acids,most of which are the precursors of volatile substances.On this basis,gas chromatography-mass spectrometry(GC-MS)was performed to elaborate the changes in volatile constituents and fatty acids as precursors.This study tested proximately 60 volatiles and 8 fatty acids at 9 growth and development stages(AF1-AF9).Of those compounds,more than 92.00%of total volatiles and 87.50%of fatty acids were terpenoid and saturated fatty acids,respectively.As shown in the PCA plot,the AF5,AF6,and AF9 stages were confirmed as completely segregated and appeared different.In addition,most of the volatiles and fatty acids first increased at the beginning of the development stage,then decreased from the AF6 development stage,and finally increased at the AF9 maturity stage.Moreover,the highest contents of terpenoid,alcohols,aldehydes,ketones,and saturated fatty acids in Jincheng orange peel oil were d-limonene,linalool,octanal,cyclohexanone,and stearic acid during development stages,respectively.Our results found that the growth stages significantly affected the volatile constituents and precursors in Jincheng orange peel oil. 展开更多
关键词 Jincheng orange volatile compounds fatty acids growth stages
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Microbial Community Profiles Related to Volatile Fatty Acids Production in Mesophilic and Thermophilic Fermentation of Waste Activated Sludge Pretreated by Enzymolysis
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作者 Xiaodong Xin Bingxin Wang +3 位作者 Junming Hong Junguo He Wei Qiu Bor-Yann Chen 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2020年第4期60-73,共14页
Mesophilic and thermophilic anaerobic fermentation performance of waste activated sludge(WAS)pretreated by enzymes catalysis associated with microbial community shifts were investigated.WAS disintegration was boosted ... Mesophilic and thermophilic anaerobic fermentation performance of waste activated sludge(WAS)pretreated by enzymes catalysis associated with microbial community shifts were investigated.WAS disintegration was boosted considerably by enzymolysis with 8750 mg/L of soluble COD release within 180 min.Mesophilic anaerobic fermentation(MAF)produced nearly equal VFA accumulation with over 3200 mg COD/L compared with that of thermophilic fermentation(TAF).Bacterial community consortia showed great shifting differences in dynamics of main T⁃RFs between MAF and TAF.Moreover,MAF was conducive to form intermediate bacterial community evenness compared to TAF,which preserved a robust function of VFA production.The enzymes catalysis prompted bio⁃energy(electricity)recovery potential of WAS organics via anaerobic fermentation(MAF/TAF)with evaluating electricity conversion efficiency of 0.75-0.82 kW·h/kg VSS(3.9 times higher than control test).Finally,this study proposed some novel thinking on future WAS treatment/management towards energy recovery coupled with energy⁃sufficient wastewater treatment by co⁃locating WAS anaerobic fermentation,MFC plant with wastewater treatment plant(s). 展开更多
关键词 waste activated sludge(WAS) enzymes catalysis volatile fatty acid(vfa) bacterial community electric energy conversion
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Processing Effect on the Physicochemical and Volatile Fatty Acid Profile of African Breadfruit (Treculia africana) Seed Oil
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作者 Titus U. Nwabueze Amarachi G. Emenonye 《Food and Nutrition Sciences》 2016年第7期627-635,共10页
African breadfruit seeds were subjected to three processing methods—parboiling, cooking and toasting, and the raw was used as control. The purpose of this research was to extract the oil from the seed and to determin... African breadfruit seeds were subjected to three processing methods—parboiling, cooking and toasting, and the raw was used as control. The purpose of this research was to extract the oil from the seed and to determine the effect of processing on the oil for physicochemical properties and volatile fatty acid profile. Physicochemical properties showed that the colour of the oil varied from golden yellow to brownish yellow with specific gravity varying between 0.802 g/cm3 and 0.813 g/cm3. Percentage yield of oil was 6.14% for raw extract, 6.62% for parboiled extract, 7.56% for toasted extract, and 5.01% for cooked extract. Acid, peroxide and saponification value for oil extracted from the raw seed varied with the processed samples value. The Volatile Fatty Acid (VFA), also known as Short Chain Fatty Acid (SCFA) found inherent in varying concentration, were formic, acetic, propionic, isobutyric, butyric, isovaleric, valeric, isocarproic, hexanoic and heptanoic acid. Overall results prove that heat results in increases in the VFA concentration of the processed oil. 展开更多
关键词 Component Formatting Style STYLING African Breadfruit volatile fatty acid (vfa) Short Chain fatty acid (SCFA) PHYSICOCHEMICAL
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A combined pig model to determine the net absorption of volatile fatty acids in the large intestine under different levels of crude fiber
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作者 Shengjun Zhao Liangkang Lv +6 位作者 Taotao Wu Zhi Feng Qiang Li Long Lei Zhengya Liu Hui Zhang Ying Ren 《Animal Models and Experimental Medicine》 CAS CSCD 2023年第4期375-380,共6页
Background:This study aimed to develop a combined model to quantify the net absorption of volatile fatty acids(VFA)in the large intestine(LI)of pigs.Methods:Fifteen female growing pigs(Duroc×Large White×Land... Background:This study aimed to develop a combined model to quantify the net absorption of volatile fatty acids(VFA)in the large intestine(LI)of pigs.Methods:Fifteen female growing pigs(Duroc×Large White×Landrace)were ranked by body weight(30±2.1 kg)on day 0 and assigned to one of three treatments,namely the basal diet containing different crude fiber(CF)levels(LCF:3.0%CF,MCF:4.5%CF,and HCF:6.0%CF).The pigs were implanted with the terminal ileum fistula and the cannulation of the ileal mesenteric vein(IMV),portal vein(PV),and left femoral artery(LFA)from days 6 to 7.[13 C]-Labeled VFA and P-aminohippuric acid were constantly perfused into the terminal ileum fistula and the cannulation of the IMV(day 15),respectively.Blood samples were collected from the PV and the LFA during perfusion(5 h),and LI samples were collected.Results:The net flux of[12 C]-acetic acid in the PV was greater for LCF versus MCF(p=0.045),but no difference was observed in the net flux of[12 C]-propionic acid(p=0.505)and[12 C]-butyric acid(p=0.35)in the PV among treatments.The deposition of[12 C]-acetic acid in the LI was greater for LCF versus MCF(p=0.014),whereas the deposition of[12 C]-propionic acid(p=0.007)and[12 C]-butyric acid(p=0.037)in the LI was greater for LCF versus HCF.Conclusions:In conclusion,this pig model was found conducive to study the net absorption of VFAs in the LI,and LCF had more net absorption of VFAs in the LI than MCF and HCF. 展开更多
关键词 crude fiber growing pigs large intestine T-type fistula volatile fatty acids
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Leaf Volatiles Induced by Mechanical Damage from Diverse Taxonomic Tree Species 被引量:2
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作者 平立岩 沈应柏 +1 位作者 金幼菊 郝建华 《Acta Botanica Sinica》 CSCD 2001年第3期261-266,共6页
Plant volatiles induced by wounding play key roles in plant-insect and plant-plant interactions. To deeply understand the mechanism of their induction by wounding and their functions in interplant communications, four... Plant volatiles induced by wounding play key roles in plant-insect and plant-plant interactions. To deeply understand the mechanism of their induction by wounding and their functions in interplant communications, four diverse tree species: ashleaf maples ( Acer negundo L.), hankow willow (Salix matsudana Koidz.), Chinese white poplar ( Populus tomentosa Carr.) and poplar opera 8277 (P. simonii x P. pyramibalis cv.), were used as materials. The blends of volatiles collected after damage were detected with GCMS. Most of the induced compounds reach high concentrations in 5 h. They are acyclic monoterpenes, fatty acid derivatives, and aromatic compounds. To authors' knowledge, dimethyl adipate, diisobutyl succinate and benthothiazole have never been reported in previous herbivore insect-plant systems, After being damaged 2 h, green leaf volatiles were released in large amount. The repellents were detected in higher concentration after 24 h. The time of releasing is different within different species, but many kinds of volatiles widely existed in different trees. There were some difference among species. Health ashleaf maple released more terpenoids, but poplars and willow produced more aromatic compounds. 展开更多
关键词 volatileS damage GC-MS TERPENOID fatty acid derivative aromatic compound
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Effects of thyme(Thymus vulgaris L.)addition on the volatile compounds of mutton broth during boiling 被引量:3
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作者 Shasha Qi Ping Zhan +3 位作者 Honglei Tian Peng Wang Xueping Ma Kaixuan Li 《Food Science and Human Wellness》 SCIE 2022年第2期305-315,共11页
To investigate the effects of thyme(Thymus vulgaris L.)addition on the flavor modification of mutton broth during boiling,three mutton-broth samples with various thyme contents 0.06%(S1),0.30%(S2),and1.50%(S3)were ana... To investigate the effects of thyme(Thymus vulgaris L.)addition on the flavor modification of mutton broth during boiling,three mutton-broth samples with various thyme contents 0.06%(S1),0.30%(S2),and1.50%(S3)were analyzed and compared,without thyme as control(0.00%,S0).The meaty,fatty,pastoral flavor and spicy were chosen as sensory attributes to evaluate the flavor of the mutton-broth samples.Sensory results were significantly different(P<0.001),with S2 having the optimum overall acceptability.A total of 99 volatile compounds were identified by gas chromatography-mass spectrometry,among which19 compounds were considered as the odor-active compounds according to their odor activity values.Significant changes(P<0.05)appeared in most volatiles in S0 with thyme addition,especially aldehydes.Free fatty acids(FFAs)were also identified,and all of them significantly increased with increased thyme(P<0.05).Correlation analysis of odor-active compounds,FFAs,and sensory attributes through partial least squares regression indicated the important volatiles and FFAs remarkably contributed to the mutton broth samples,and further confirmed that the 0.30%of thyme may be a desirable addition amount for the sensory characteristics of mutton broth. 展开更多
关键词 Mutton broth THYME volatile compounds Free fatty acids GC-MS PLSR
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Effects of Diet on the Volatile Flavor and Nutritional Ingredients of Common Octopus(Octopus vulgaris) 被引量:1
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作者 LUO Qihao WANG Weijun +5 位作者 LI Zan ZHU Xinghua WANG Xue ZHANG Tonghua XU He YANG Jianmin 《Journal of Ocean University of China》 SCIE CAS CSCD 2021年第2期393-401,共9页
Cephalopods are important economic shellfish that have been developed extensively in the coastal water of various countries. Octopus vulgaris is a large-scaled economic cephalopod that is mainly cultured in South Chin... Cephalopods are important economic shellfish that have been developed extensively in the coastal water of various countries. Octopus vulgaris is a large-scaled economic cephalopod that is mainly cultured in South China. This study explored the effect of different diets on the volatile flavor and nutritional ingredients of O. vulgaris. Four diets were tested in four groups: Group A(fish(Scomberomorus niphonius)), Group B(crab(Helice tridens tientsinensis Rathbun)), Group C(clam(Mactra veneriformis)), and Group D(squid(Loligo japonica)). Octopus muscles were sampled after 36 days of feeding, and volatile flavor substances(VFSs), fatty acids(FAs), and amino acids(AAs) were detected. Results showed that the VFSs, FAs, and AAs of octopus in the four groups were obviously different. The sum of volatile ketones and aldehydes was higher in Group B than in the other groups, which could present much more flavors. All groups were abundant in unsaturated FAs, including eicosapentaenoic acid(EPA) and docosahexaenoic acid(DHA). In terms of content and variety, the FAs in Group B were more beneficial to human health than those in the other groups. The content of each AA in Group B was basically higher than those in the other groups and was significantly higher than that in Group D(P < 0.05). Comparing the VFSs, FAs, and AAs in samples fed with four kinds of diets, the results indicate that using crab to feed O. vulgaris can achieve better effects on volatile flavor and nutritional ingredients. 展开更多
关键词 Octopus vulgaris volatile flavor substances fatty acids amino acids diet effect
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Effect of TRH and TSH on Circulatory Glucose and Fatty Acids Responses in Hypoinsulenemic Male Dwarf Goats
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作者 Rubina Mushtaq Rehana Mushtaq +1 位作者 Abdul Majeed Cheema Sobia Khwaja 《Advances in Bioscience and Biotechnology》 2014年第13期994-1002,共9页
Diabetes mellitus or hypoinsulinemia was induced successfully in the male dwarf goats aged be-tween 2 - 3 years with 2 consecutive administrations of streptozotocin. A comparable group of intact control goats was also... Diabetes mellitus or hypoinsulinemia was induced successfully in the male dwarf goats aged be-tween 2 - 3 years with 2 consecutive administrations of streptozotocin. A comparable group of intact control goats was also maintained. In ruminants including goats unlike non-ruminants, insulin generally displays ineffectiveness or resistance in their biochemical setup to facilitate gluco-neogenesis, the only source of glucose in these animals. In present study almost in the absence of insulin through induced hypoinsulinemia the effects of thyrotropin releasing hormone (TRH) (30 μg/kg body weight) and thyroid stimulating hormone (TSH) (2.5 μg/kg body weight) on circulatory glucose and different fatty acid fractions were studied in insulin resistant ruminant model. Fatty acid fractions were estimated by gas chromatography. Both TRH and TSH administration lowered glycemia in insulin deficient goats compared to the controls but significantly with TSH dose only. In intact goats the detectable circulating long chain fatty acids (LCFAs) fractions of lauric, myristic, palmitic, stearic, oleic and linoleic acid were undetected except linoleic acid in the hypoinsulinemic state, however were found restored following TRH and TSH administrations and some of LCFAs;stearic (6417%), oleic (1676%) and linoleic acid (1225%) increased exceptionally with TSH dose. In Intact goats however the hormones variedly increased the fractions. The volatile fatty acid fractions (VFAs) of formic, acetic, propionic, iso-butyric, n-butyric, iso-valeric, n-valeric, iso-caproic, n-caproic and heptanoic acid were detected in the goats. The most VFAs fractions markedly increased in hypoinsulinemic goats compared to the control goats following TRH and TSH infusion. These results have indicated that endogenously stimulated thyroid hormones with TRH and TSH in insulin deficient state inhibit the mechanisms of utilizing the fatty acids in glucose production. Therefore the study reveals thyroid hormones inhibitory effects on gluconeogenesis in insulin resistance and hyperglycemia. 展开更多
关键词 GLUCOSE Goats Induced Hypoinsulinemia Long Chain fatty acidS Thyroid Stimulating HORMONE Thyrotrophin Releasing HORMONE volatile fatty acidS
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Valorisation of industrial hemp (Cannabis sativa L.) residues and cheese whey into volatile fatty acids for single cell protein production
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作者 Carlo Moscariello Silvio Matassa +2 位作者 Francesco Pirozzi Giovanni Esposito Stefano Papirio 《Environmental Science and Ecotechnology》 SCIE 2024年第5期369-380,共12页
The production of single cell protein(SCP)using lignocellulosic materials stands out as a promising route in the circular bioeconomy transition.However,multiple steps are necessary for lignocellulosics-to-SCP processe... The production of single cell protein(SCP)using lignocellulosic materials stands out as a promising route in the circular bioeconomy transition.However,multiple steps are necessary for lignocellulosics-to-SCP processes,involving chemical pretreatments and specific aerobic cultures.Whereas there are no studies that investigated the SCP production from lignocellulosics by using only biological processes and microbial biomass able to work both anaerobically and aerobically.In this view,the valorisation of industrial hemp(Cannabis sativa L.)biomass residues(HBRs),specifically hurds and a mix of leaves and inflorescences,combined with cheese whey(CW)was investigated through a semi-continuous acidogenic co-fermentation process(co-AF).The aim of this study was to maximise HBRs conversion into VFAs to be further used as carbon-rich substrates for SCP production.Different process conditions were tested by either removing CW or increasing the amount of HBRs in terms of VS(i.e.,two and four times)to evaluate the performance of the co-AF process.Increasing HBRs resulted in a proportional increase in VFA production up to 3115 mg HAc L^(-1),with experimental production nearly 40%higher than theoretical predictions.The synergy between HBRs and CW was demonstrated,proving the latter as essential to improve the biodegradability of the former.The produced VFAs were subsequently tested as substrates for SCP synthesis in batch aerobic tests.A biomass concentration of 2.43 g TSS L^(-1) was achieved with a C/N ratio of 5.0 and a pH of 9.0 after two days of aerobic fermentation,reaching a protein content of 42%(g protein per g TSS).These results demonstrate the overall feasibility of the VFA-mediated HBR-to-SCP valorisation process. 展开更多
关键词 Hemp biomass residues Cheese whey volatile fatty acids acidogenic fermentation Single cell protein
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Noria-PEI改性PVA载体固定化溶菌酶用于污泥发酵产VFAs研究
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作者 王昊龙 张恩泽 +8 位作者 王梓诚 赵瑜涵 南军 孙彦民 马爱静 周立山 刘丽强 蔡巷 段兴宇 《工业水处理》 CAS CSCD 北大核心 2024年第4期155-163,共9页
生物酶促进污泥厌氧消化具有反应温和、高效环保等优点,然而回收困难和催化稳定性差严重制约其应用,固定化酶是解决上述问题的关键。采用水轮酚(Noria)和聚乙烯亚胺(PEI)共沉积法改性聚乙烯醇(PVA)载体,并研究了Noria-PEI改性PVA载体固... 生物酶促进污泥厌氧消化具有反应温和、高效环保等优点,然而回收困难和催化稳定性差严重制约其应用,固定化酶是解决上述问题的关键。采用水轮酚(Noria)和聚乙烯亚胺(PEI)共沉积法改性聚乙烯醇(PVA)载体,并研究了Noria-PEI改性PVA载体固定溶菌酶对污泥厌氧发酵产挥发性脂肪酸(VFAs)效能的影响。结果表明,固定化溶菌酶可强化污泥发酵提高SCOD,在36 h内SCOD最高浓度达到2 892.4 mg/L,相比空白组提升3.4倍(第6天),VFAs质量浓度在第4天达到峰值2 130.8 mg/L,乙酸和丙酸占比达到61.8%~80.7%。固定酶系统中污泥的平均粒径为42.957μm,比表面积为0.413 m^(2)/g,固定化溶菌酶强化了颗粒态污泥水解。微生物群落结构分析显示,在固定酶系统中Firmicutes、Proteobacteria和Bacteroides等水解产酸菌门占比较高;在属水平上,以Macellibacteroides、Petrimonas、Lactobacillus和Clostridium_sensu_stricto_1菌属为主,从微观层面上解释了固定酶强化污泥发酵产酸机理。 展开更多
关键词 水轮酚 聚乙烯醇载体 固定酶 剩余污泥 挥发性脂肪酸
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超声波预处理对餐厨垃圾产VFAs的影响 被引量:19
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作者 王佳明 蒋建国 +2 位作者 宫常修 张玉静 李梦露 《中国环境科学》 EI CAS CSCD 北大核心 2014年第5期1207-1211,共5页
采用超声波预处理餐厨垃圾以提高产挥发性脂肪酸(VFAs)产率.结果表明,在超声强度720W/L下处理15min后,餐厨垃圾SCOD含量比原样中SCOD提高了1倍,其中有机质中碳水化合物溶出量最大,由原样中8.2g/L提高到处理后的43.5g/L;在pH=6、温度35... 采用超声波预处理餐厨垃圾以提高产挥发性脂肪酸(VFAs)产率.结果表明,在超声强度720W/L下处理15min后,餐厨垃圾SCOD含量比原样中SCOD提高了1倍,其中有机质中碳水化合物溶出量最大,由原样中8.2g/L提高到处理后的43.5g/L;在pH=6、温度35℃条件下,对含固率约为12%的餐厨垃圾进行厌氧发酵,未预处理和超声处理后的餐厨垃圾产生的VFAs最大值分别达到33.4,42.5g/L,经超声预处理的餐厨垃圾产VFAs的量提高了27.2%. 展开更多
关键词 餐厨垃圾 超声波 挥发性脂肪酸 厌氧消化 volatile fatty acidS (vfas)
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NaCl对餐厨垃圾厌氧发酵产VFA浓度及组分的影响 被引量:32
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作者 王权 宫常修 +1 位作者 蒋建国 张玉静 《中国环境科学》 EI CAS CSCD 北大核心 2014年第12期3127-3132,共6页
通过间歇实验研究了最适反应条件(p H值为6.0、温度为35℃)下Na Cl含量对餐厨垃圾厌氧发酵产挥发性脂肪酸(VFA)的影响.考察了Na Cl含量为0.0,3.0,6.0,9.0,12.0g/L下的有机酸浓度及组成情况.结果表明,Na Cl对厌氧发酵液中VFA浓度影响显著... 通过间歇实验研究了最适反应条件(p H值为6.0、温度为35℃)下Na Cl含量对餐厨垃圾厌氧发酵产挥发性脂肪酸(VFA)的影响.考察了Na Cl含量为0.0,3.0,6.0,9.0,12.0g/L下的有机酸浓度及组成情况.结果表明,Na Cl对厌氧发酵液中VFA浓度影响显著,随Na Cl含量提高VFA浓度呈下降趋势,当Na Cl含量达到12.0g/L时,VFA浓度在第114h达到最大值4.14g/L,仅为未添加Na Cl条件下的10.1%.发酵液中各组分变化经历丁酸积累、乙酸积累与乙酸消耗3个阶段,Na Cl对厌氧发酵类型影响不显著,各批次发酵均为丁酸型发酵,仅当Na Cl含量超过6.0g/L时丁酸积累阶段时间延长. 展开更多
关键词 餐厨垃圾 挥发性脂肪酸(vfa) 厌氧发酵 NACL
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粪秆结构配比厌氧发酵中pH、VFA与产气效果的关系 被引量:31
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作者 张彤 李伟 +2 位作者 李文静 李轶冰 杨改河 《农业环境科学学报》 CAS CSCD 北大核心 2010年第12期2425-2430,共6页
为探索发酵原料产气量与pH值、挥发性脂肪酸之间的关系,确定最佳原料配比以及发酵温度是关键。通过试验在恒温条件下以不同配比的鸡粪、麦秆混合物为原料,在25~40℃范围内进行厌氧发酵,研究pH值和挥发性脂肪酸对沼气产量的影响。结果显... 为探索发酵原料产气量与pH值、挥发性脂肪酸之间的关系,确定最佳原料配比以及发酵温度是关键。通过试验在恒温条件下以不同配比的鸡粪、麦秆混合物为原料,在25~40℃范围内进行厌氧发酵,研究pH值和挥发性脂肪酸对沼气产量的影响。结果显示,在约50d的发酵过程中,以40℃、鸡粪和麦秸3∶1处理的(简称鸡麦3∶1)累积产气量最高,达11492mL,25℃、鸡麦3∶1处理的累积产气量最低,为6227mL。在25、30℃发酵条件下,随着麦秆比例的增加,产气量逐渐增加;在35、40℃发酵条件下,随着麦秆比例的减少,产气量逐渐增加。pH值与日产气量成正比,而挥发性脂肪酸与日产气量成反比。 展开更多
关键词 小麦秸秆 鸡粪 厌氧发酵 PH值 挥发性脂肪酸
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高盐高油对餐厨垃圾厌氧发酵酶活性及产VFAs的影响 被引量:8
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作者 谷士艳 闫屹嵩 +3 位作者 张文一 孙继阳 张敏 李轶 《农业工程学报》 EI CAS CSCD 北大核心 2021年第6期228-234,共7页
为探究高盐高油对厌氧发酵产酸及相关酶活性的影响,该研究以餐厨垃圾为发酵原料,在接种物质量为30%、TS(Total Solids)为8%、温度为35℃、初始pH值为7的条件下进行批式厌氧发酵试验,研究盐、油质量浓度为5、7、9、11、13、16 g/L的6个... 为探究高盐高油对厌氧发酵产酸及相关酶活性的影响,该研究以餐厨垃圾为发酵原料,在接种物质量为30%、TS(Total Solids)为8%、温度为35℃、初始pH值为7的条件下进行批式厌氧发酵试验,研究盐、油质量浓度为5、7、9、11、13、16 g/L的6个条件对发酵过程中的SCOD(Solluted Chemical Oxigen Demand)、VFAs(Volatile Fatty Acids)、淀粉酶、蛋白酶、辅酶F420和脱氢酶活性的影响。结果表明:随着盐油浓度的提高,SCOD峰值下降了23%~38%,并出现了2~3 d的延迟;高盐高油条件下产酸以丁酸为主,丙酸、乙酸和异戊酸含量次之,正己酸、异丁酸、正戊酸的含量最低,不同盐油条件下VFAs各组分比例差距较小;相关酶活性峰值均降低了5%~35%,相关酶活性峰值均推迟了3~6 d出现,盐油浓度越高抑制现象越明显。研究结果可为高盐高油对厌氧发酵的影响和后续试验提供参考。 展开更多
关键词 垃圾 发酵 酶活性 盐分 油脂 挥发性脂肪酸(vfas)
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不同原料配比对厌氧发酵过程中产气量VFA和脱氢酶活性的影响 被引量:21
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作者 张洪宾 谷洁 +2 位作者 孙薇 高华 王小娟 《农业环境科学学报》 CAS CSCD 北大核心 2012年第2期422-427,共6页
以牛粪和小麦秸秆为发酵原料,研究了不同牛粪(M)与小麦秸秆(S)的干物质配比(牛粪与秸秆的比例为1∶1、2∶1和3∶1)对厌氧发酵产气过程的影响。结果表明,添加小麦秸秆处理的产气量显著高于秸秆与牛粪单独发酵处理(P<0.05),其中牛粪与... 以牛粪和小麦秸秆为发酵原料,研究了不同牛粪(M)与小麦秸秆(S)的干物质配比(牛粪与秸秆的比例为1∶1、2∶1和3∶1)对厌氧发酵产气过程的影响。结果表明,添加小麦秸秆处理的产气量显著高于秸秆与牛粪单独发酵处理(P<0.05),其中牛粪与秸秆的配比是1∶1的产气量为(31823.7±691.2)mL,比秸秆、牛粪以及牛粪与秸秆比例为2∶1和3∶1四个处理的产气量分别提高了208.7%、11.5%、2.8%和5.2%。因此,以M∶S=1∶1进行混合厌氧发酵效果最好。挥发性脂肪酸(VFA)与日产量间呈极显著性正相关(P<0.01),但脱氢酶活性与产气量相关性不显著(P>0.05)。 展开更多
关键词 厌氧发酵 粪秆配比 挥发性脂肪酸 产气量
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