Adaptation fermentation of Pichia stipitis and combination detoxification on steam exploded lignocellulosic prehydrolyzate

Yeast Pichia stipitis CBS 5776 was developed through adaptation fermentation step by step in steam exploded corn stover prehydrolyzate because high concentration of weak acids and other inhibitors present in the prehydrolyzate could degrade the fermentability. However, the adaptability of Pichia stipitis CBS 5776 in the prehydrolyzate was so limited that steam strip-ping and overliming were applied to remove these inhibitors from it. Corn stover was steam exploded;the filtrate of steam exploded corn stover was hydrolyzed with dilute sulfuric acid, and then the acid hydrolyzate was detoxified and fermented by Pichia stipitis CBS 5776. Steam stripping could remove volatile com-pounds from the acid hydrolyzate and the fil-trate. At a steam stripping time of 120min, 81% acetic acid and 59% formic acid were removed from the acid hydrolyzate, 77% acetic acid and 45% formic acid were removed from the filtrate, while furfural was stripped off completely from the acid hydrolyzate and the filtrate. Overliming could reduce the contents of furfural and phe-nolics present in the acid hydrolyzate, however, sugars, especially pentoses, were also removed partially. It was necessary to detoxify the acid hydrolyzate in order to ferment the sugars to ethanol. Acid hydrolyzate detoxified with a combination of steam stripping for 120 min and overliming at pH11 and 60℃ for 90 min, its fer-mentability was significantly improved. Xylose was consumed nearly completely in 24h with an ethanol yield of 15.92g/l, 80.34% of theoretical.

Production of whey protein hydrolyzates and its incorporation into milk

Whey proteins provide an excellent source of low-molecular-weight bioactive peptides with important functional properties and bioactivities like antihypertensive,opioid,and antimicrobial effects.Presence of peptide molecules with lower molecular weight has a great role in food for health promotion.In this investigation,the release of low-molecular-weight peptides from whey protein concentrate was attempted by using enzymatic digestion.The hydrolyzate was then incorporated into milk to obtain enriched milk(EM)with low-molecular-weight peptides.Based on sensory analysis of EM,electrophoretic and RP-HPLC studies,hydrolyzates of 10%protein(degree of hydrolysis 5%;enzyme/substrate E/S,1:50)were finally incorporated into milk at 20%(v/v)to develop an acceptable product enriched with low-molecular-weight peptides.EM had higher protein content,viscosity and emulsifying properties than control milk with 3%fat.It is recommended that EM should not be sterilized as it results in coagulation,but can be safely pasteurized and spray dried without any undesirable effects.Maximum ACE-inhibition activity was obtained in hydrolyzate,followed by EM.This study is expected to boost the opportunity for the dairy industry to venture further into the nutraceutical dairy market.

Effect of high-protein peptide-based formula compared with isocaloric isonitrogenous polymeric formula in critically ill surgical patient

BACKGROUND Malnutrition is common in critically ill patients,and it is associated with an increased risk of complications.Early enteral nutrition with adequate caloric and protein intake is critical nevertheless it is difficult to achieve.Peptide-based formulas have been shown to be beneficial in patients with feeding intolerance.However,there are limited studies showing the efficacy and safety of high-protein peptide-based formula in critically ill surgical patients.AIM To determine the effects of a high-protein peptide formulation on gastrointestinal tolerance,nutritional status,biochemical changes,and adverse events in patients in the surgery intensive care unit(SICU)compared to an isocaloric isonitrogenous standard polymeric formulation.METHODS This study was a multi-center double-blind,randomized controlled trial.We enrolled adult patients in the surgical intensive care unit,age≥15 years and expected to receive enteral feeding for at least 5-14 d post-operation.They were randomly assigned to receive either the high-protein peptide-based formula or the isocaloric isonitrogenous standard formula for 14 d.Gastric residual volume(GRV),nutritional status,body composition and biochemical parameters were assessed at baseline and on days 3,5,7,9,11,and 14.RESULTS A total of 19 patients were enrolled,9 patients in the peptide-based formula group and 10 patients in the standard formula group.During the study period,there were no differences of the average GRV,body weight,body composition,nutritional status and biochemical parameters in the patients receiving peptide-based formula,compared to the standard regimen.However,participants in the standard formula lost their body weight,body mass index(BMI)and skeletal muscle mass significantly.While body weight,BMI and muscle mass were maintained in the peptide-based formula,from baseline to day 14.Moreover,the participants in the peptide-based formula tended to reach their caloric target faster than the standard formula.CONCLUSION The study emphasizes the importance of early nutritional support in the SICU and showed the efficacy and safety of a high-protein,peptide-based formula in meeting caloric and protein intake targets while maintaining body weight and muscle mass.

Biomass accumulation of Panax vietnamensis in cell suspension cultures varies with addition of plant growth regulators and organic additives

Objective: To evaluate the impact of plant growth regulators including kinetin(KN),benzyl adenine and naphthalene acetic acid, yeast extract and casein hydrolyzate on biomass accumulation of Vietnamese ginseng Panax vietnamensis(P. vietnamensis) in cell suspension culture.Methods: Cell suspension cultures were established from friable calluses derived from leaves and petioles of 3-year-old in-vitro P. vietnamensis plants. The cell suspension cultures were grown in Murashige and Skoog basal media supplemented with various concentrations of KN, benzyl adenine, naphthalene acetic acid, and yeast extract and casein hydrolyzate.Results: All tested factors generated an increase in the cell biomass of P. vietnamensis in suspension culture, but the impact of each varies depended on the factor type, concentration, and incubation period. Addition of 2.0 mg/L KN resulted in the largest biomass increase after 24 d,(57.0 ± 0.9) and(3.1 ± 0.1) mg/m L fresh and dry weight, respectively,whereas addition of benzyl adenine or naphthalene acetic acid produced optimum levels of Panax cell biomass at 1.0 and 1.5 mg/L, respectively. Addition of the elicitor yeast extract led to a 1.4–2.4 fold increase in biomass of P. vietnamensis, while addition of casein hydrolyzate enhanced biomass accumulation 1.8–2.6 fold.Conclusions: The addition of each factor causes significant changes in biomass accumulation of P. vietnamensis. The largest biomass accumulation is from cultures grown in MS media containing 2.0 mg/L KN for 24 d. The outcome of the present study provides new insights into the optimal suspension culture conditions for studies on the in vitro cell biomass production of P. vietnamensis.

STUDY ON HYDROLYSIS OF MACROMOLECULAR GELATIN WITH ENZYMES IN COMBINATION MODE

The enzymatic hydrolysis of macromolecular gelatin with AS1.398 neutral protease, bromelain and their combinations was studied by estimating the molecular weights of their hydrolytic products. It was discovered that the products hydrolyzed by using combination enzymes had lower molecular weight than those obtained by using single ones, and the kind of enzymes, their combination mode and addition sequence are effective ways to control the molecular weights of gelatin hydrolyzates.

Hydrolysis Activities of Resins of Complexes Made from Polysaccharides and Ce^(4+)

Resins of complexes made from agarose-Ce4+ (RCA-Ce) and chitosan-Ce4+ (RCC-Ce) were prepared. Hydrolysis rates of methamidophos, omethoate and chlorpyrifos treated by RCA-Ce were 32.39%, 27. 12% and 46.62%, respectively, those of chlorpyrifos and methamidophos in mung bean sprout juice 38.28% and 35.45% , and that of chlorpyrifos in tea extract 59.76% . Hydrolysis rates of protein in tea extract treated by RCA-Ce increased by 86.46% . RCC-Ce could be employed in the apple juice production. The contents of methamidophos and parathion-methyl in the juice treated by RCC-Ce decreased 58.76% and 71.92% . Furthermore, RCC-Ce was used to clarification for beer by the ways of a column. RCC-Ce could hydrolyze sensitive protein and increase contents of free amino acid in the beer. Therefore, the beer treated by RCC-Ce could stay oxidation and aging procedure due to some metal ions being absorbed by RCC-Ce.

Partially hydrolyzed guar gum in pediatric functional abdominal pain

AIM:To assess the effects of partially hydrolyzed guar gum(PHGG) diet supplement in pediatric chronic abdominal pain(CAP) and irritable bowel syndrome(IBS).METHODS:A randomized,double-blind pilot study was performed in sixty children(8-16 years) with functional bowel disorders,such as CAP or IBS,diagnosed according to Rome Ⅲ criteria.All patients underwent ultrasound,blood and stool examinations to rule out any organic disease.Patients were allocated to receive PHGG at dosage of 5 g/d(n = 30) or placebo(fruitjuice n = 30) for 4 wk.The evaluation of the efficacy of fiber supplement included IBS symptom severity score(Birmingham IBS Questionnaire),severity of abdominal pain(Wong-Baker Face Pain Rating Score) and bowel habit(Bristol Stool Scale).Symptom scores were completed at 2,4,and 8 wk.The change from baseline in the symptom severity scale at the end of treatment and at 4 wk follow-up after treatment was the primary endpoint.The secondary endpoint was to evaluate compliance to supplementation with the PHGG in the pediatric population.Differences within groups during the treatment period and follow-up were evaluated by the Wilcoxon signed-rank test.RESULTS:The results of the study were assessed considering some variables,such as frequency and intensity of symptoms with modifications of the bowel habit.Both groups were balanced for baseline characteristics and all patients completed the study.Group A(PHGG group) presented a higher level of efficacy compared to group B(control group),(43% vs 5%,P = 0.025) in reducing clinical symptoms with modification of Birmingham IBS score(median 0 ± 1 vs 4 ± 1,P = 0.025),in intensity of CAP assessed with the Wong-Baker Face Pain Rating Score and in normalization of bowel habit evaluated with the Bristol Stool Scale(40% vs 13.3%,P = 0.025).In IBS subgroups,statistical analysis shown a tendency toward normalization of bowel movements,but there was no difference in the prevalence of improvement in two bowel habit subsets.PHGG was therefore better tolerated without any adverse effects.CONCLUSION:Although the cause of pediatric functional gastrointestinal disorders is not known,the results show that complementary therapy with PHGG may have beneficial effects on symptom control.

Effect of Dietary Supplementation with Hydrolyzed Wheat Gluten on Growth Performance, Cell Immunity and Serum Biochemical Indices of Weaned Piglets (Sus scrofa)

To investigate the effects of dietary supplementation with hydrolyzed wheat gluten （HWG） on growth performance, cell immunity and serum biochemical indices of weaned piglets, 160 crossed （Large White×andrace） and weaned piglets were randomly divided into 4 treatments with 4 replicates of 10 piglets each. The piglets in each treatment were fed an experimental diet containing either 0 g kg-1 HWG （control group）, 30 g kg-1 HWG （3% HWG group）, 50 g kg-1 HWG （5% HWG group）, or 2.5 g kg-1 glycyl-L-glutamine （0.25% Gly-Gln group）. The results showed that the diarrhea rates in 3% HWG and 5% HWG groups were significantly lower than in control group from d 1 to 14 （P〈0.05）, while the average daily gain （ADG） in each of two groups was increased （P〉0.05）. When compared with control group, dietary supplementation with 3% HWG increased the ratio of CD4＋：CD8＋ and the ratio of serum albumin and globulin concentrations （A：G） on d 14 and 28, as well as the proliferation of T- and B-lymphocytes （P〉0.05） on d 28. In addition, on d 14 and 28, the A：G ratio in 5% HWG group was significantly higher than in control group （P〈0.05）, while the ratio of CD4＋：CD8＋ increased slightly （P〉0.05）. Interestingly, 0.25% Gly-Gln group had higher proportion of CD3＋ （P〉0.05） and CD4＋ （P〈0.05） on d 14 than control group, but growth performances of 0.25% Gly-Gln group were negatively affected at all experiment stages. These results suggested that HWG might improve the growth performance of piglets by strengthening cell immunity and decreasing the occurrence of diarrhea during the prophase after weaning.

Relation of Mineralizable N to Organic N Components in Dark Loessial Soils

Mineralizable N and organic N components in different layers (0～15, 15～30,30～45, 45～60, 60～80 and 80～100 cm) of six soils with different fertilities sampled from YongshouCounty, Shaanxi Province, China, were determined by the aerobic incubation method and the Bremnerprocedure, respectively. Correlation, multiple regression and path analyses were performed to studythe relation of mineralizable N to organic N components. Results of correlation and regressionanalyses showed that the amounts of the N mineralized were parallel to, and significantly correlatedwith, the total acid hydrolyzable N, but was not so with the acid-insoluble N. Of the hydrolyzableN, the amino acid N and the ammonia N had a highly consistent significant correlation with themineralized N, and their partial regression coefficients were significant in the regressionequations, showing their importance in contribution to the mineralizable N. The amino sugar N, onthe other hand, had a relatively high correlation with the mineralized N, but their partialregression coefficients were not significant in the regression equations. In contrast, thehydrolyzable unknown N had no such relations. Path analysis further indicated that the amino acid Nand ammonia N made great direct contributions to the mineralized N, but the contributions of theamino sugar N were very low. These strongly suggested that the mineralized N in the soils tested wasmainly from the hydrolyzable N, particularly the amino acid N and ammonia N which are the majorsources for its production.

酶解乳蛋白对初生仔猪小肠组织学结构及隐窝细胞增殖的影响(英文)

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Partially hydrolyzed guar gum attenuates non-alcoholic fatty liver disease in mice through the gut-liver axis

BACKGROUND The gut-liver axis has attracted much interest in the context of chronic liver disease pathogenesis.Prebiotics such as dietary fibers were shown to attenuate non-alcoholic fatty liver disease(NAFLD)by modulating gut microbiota.Partially hydrolyzed guar gum(PHGG),a water-soluble dietary fiber,has been reported to alleviate the symptoms of various intestinal diseases and metabolic syndromes.However,its effects on NAFLD remain to be fully elucidated.To determine whether treatment with PHGG attenuates NAFLD development in mice through the gut-liver axis.METHODS Seven-week-old male C57BL/6J mice with increased intestinal permeability were fed a control or atherogenic(Ath)diet(a mouse model of NAFLD)for 8 wk,with or without 5%PHGG.Increased intestinal permeability was induced through chronic intermittent administration of low-dose dextran sulfate sodium.Body weight,liver weight,macroscopic findings in the liver,blood biochemistry[aspartate aminotransferase(AST)and alanine aminotransferase(ALT),total cholesterol,triglyceride,free fatty acids,and glucose levels],liver histology,myeloperoxidase activity in liver tissue,mRNA expression in the liver and intestine,serum endotoxin levels in the portal vein,intestinal permeability,and microbiota and short-chain fatty acid(SCFA)profiles in the cecal samples were investigated.RESULTS Mice with increased intestinal permeability subjected to the Ath diet showed significantly increased serum AST and ALT levels,liver fat accumulation,liver inflammatory(tumor necrosis factor-αand monocyte chemotactic protein-1)and fibrogenic(collagen 1a1 andαsmooth muscle actin)marker levels,and liver myeloperoxidase activity,which were significantly attenuated by PHGG treatment.Furthermore,the Ath diet combined with increased intestinal permeability resulted in elevated portal endotoxin levels and activated toll-like receptor(TLR)4 and TLR9 expression,confirming that intestinal permeability was significantly elevated,as observed by evaluating the lumen-to-blood clearance of fluorescein isothiocyanate-conjugated dextran.PHGG treatment did not affect fatty acid metabolism in the liver.However,it decreased lipopolysaccharide signaling through the gut-liver axis.In addition,it significantly increased the abundance of cecal Bacteroides and Clostridium subcluster XIVa.Treatment with PHGG markedly increased the levels of SCFAs,particularly,butyric acid,acetic acid,propionic acid,and formic acid,in the cecal samples.CONCLUSION PHGG partially prevented NAFLD development in mice through the gut-liver axis by modulating microbiota and downstream SCFA profiles.

Nutritional and health benefits of semi-elemental diets: A comprehensive summary of the literature

AIM:To critically review and summarize the literature on nutritional and health outcomes of semi-elemental formulations on various nutritionally vulnerable patient populations who are unable to achieve adequate nutrition from standard oral diets.METHODS:We conducted a comprehensive literature search of Pubmed and Embase databases.We manually screened articles that examined nutritional and health outcomes(e.g.,growth,disease activity,gastrointestinal impairment,mortality,and economic impact)among various patient groups receiving semi-elemental diets.This review focused on full-text articles of randomized controlled clinical trials and other intervention studies,but pertinent abstracts and case studies were also included.Results pertaining primarily to tolerance,digestion,and absorption were summarized for each patient population in this systematic review.RESULTS:Results pertaining primarily to tolerance,digestion,and absorption were summarized for each patient population.The efficacy of semi-elemental whey hydrolyzed protein(WHP)diet have been reported in various nutritionally high risk patient populations including-Crohn’s disease,short bowel syndrome,acute and chronic pancreatitis,cerebral palsy,cystic fibrosis,cerebrovascular accidents,human immunodeficiency virus,critically ill,and geriatrics.Collectively,the evidence from the medical literature indicates that feeding with a semi-elemental diet performs as well or better than parenteral or amino acid based diets in terms of toler-ance,digestion,and nutrient assimilation measures across various disease conditions.CONCLUSION:Based on this comprehensive review of the literature,patient populations who have difficulty digesting or absorbing standard diets may be able to achieve improved health and nutritional outcomes through the use of semi-elemental WHP diets.

Effect of salt solutions on chain structure of partially hydrolyzed polyacrylamide

The effect of salt solutions(NaCl,Na2SO4 and CaCl2) on the conformational properties of partially hydrolyzed polyacrylamide(HPAM) was investigated by using static laser light scattering(SLLS).The special interaction between CaCl2 solution and HPAM was also researched.Experimental results show that the chain structure of HPAM is interrelated with the charge density,the kind and the concentration of salt solutions.The mean-square radius of gyration(Rz) and the second virial coefficient(A2) of HPAM decrease with increasing concentration of salt solutions,and the salt effect tends towards the maximum when the concentration of salt solution is increased to some amount.

Hydrolysis Activities of the Particle of Agarose-Ce^(4+) Complex for Compounds Containing Phosphodiester or Peptide Bonds

Hydrolysis activities of PACC (particle of agarose-Ce4+ complex, newly made through double emulsification) forcompounds containing phosphodiester or peptide bonds were studied. The results showed that PACC could hydrolyzeorganophosphorous pesticides not only in water but also in vegetable juice or tea extract. Hydrolysis rates of methamidophos,omethoate and chlorpyrifos in water are 32.39%, 27.12% and 46.62% respectively, those of chlorpyrifos and methami-dophos in mung sprout juice 38.28% and 35.45% respectively, and that of chlorpyrifos in tea extract 59.76%. Hydrolysisrates of BSA (bovine serum albumin) in water and protein in tea extract by PACC increase by 54.30% and 86.46% respec-tively as compared with the control.

Two New Phenolic Constituents from the Stems of Euphorbia griffithii

Phytochemical studies on MeOH extract of stems of Euphorbia griffithii led to the isolation of one new hydrolyzable tannin dimer,corilagiffithiin(1)and one new galloyl-glucoside(2),alongside six known ones(3-8).Their structures and absolute configurations were determined by in depth spectroscopic analyses and comparison of their 1D NMR and MS data with literature reported values.Configurations of sugar moieties were determined by acidic hydrolysis and subsequent GC analysis of their corresponding trimethylsilylated l-cysteine adduct.At a concentration of 50μM,compounds 1-3 showed no anti-inflammatory activities.

酸水解植物蛋白热反应制备烤牛肉香基的工艺研究

研究影响酸水解植物蛋白热反应制备烤牛肉香基的因素,同时考察不同反应条件对酸水解植物蛋白热反应制备烤牛肉香基的影响。在单因素初步试验的基础上,以烤牛肉香基的感官评分值为考察指标,通过单因素试验、正交试验及方差分析,考察各加工条件对酸水解植物蛋白热反应制备烤牛肉香基的影响,并采用顶空固相微萃取和气相色谱-质谱联用技术对最优条件下反应产物的挥发性物质进行检测分析。结果表明:添加酸水解植物蛋白126 g、I+G 2.5 g、L-谷氨酸1.0 g、L-半胱氨酸盐酸盐5.0 g、L-脯氨酸1.0 g、甘氨酸5.0 g、盐酸硫胺2.5 g、葵花子油4.0 g、还原糖0.075 mol,热反应条件为反应温度115℃、反应时间90 min、反应p H值7.5时制备的烤牛肉香基风味浓厚、圆润、真实、持久,香气评分值可达到95.86。对挥发性物质分析表明,最优条件下制备的烤牛肉香基中主要香气成分为吡嗪类、酮类、酯类、醇类、醛类化合物和一些杂环化合物。产物中含有的吡嗪类、酮类、醇类、醛类等化合物是重要的烤香和肉香味关键贡献性成分,烤牛肉香味特征明显。

NaOH/Urea Swelling Treatment and Hydrothermal Degradation of Waste Cotton Fiber

In this study,waste cotton fabric was used as cellulose raw material and pretreated in aqueous NaOH/urea solution system to investigate the effect of NaOH/urea pretreatment solution on the hydrolysis of cotton fiber.The cotton fiber was pretreated with different conditions of aqueous NaOH/urea solution,and the pretreated cotton fiber was hydrolyzed under the same conditions as the original cotton fiber.The results of characterization analysis showed that water retention value of pretreated cotton fiber was higher than that of unpretreated sample.Moreover,the cotton fiber presented both a convoluted structure and a coarser surface,XRD results suggested that the crystallinity degree of cellulose decreased dramatically,more cellulose II appeared,and the hydrogen bond is broken.Among the different pretreatment conditions,the pretreatment effect was the best when the reaction temperature was 0°C,the solid-liquid ratio was 2:50,and the NaOH/urea ratio was 7:12.The hydrolysis experiments of pretreated and unpretreated cotton fibers showed that when the hydrothermal temperature was 230°C,the heat preservation was 2 h,and the hydrochloric acid concentration was 5 wt.%,the glucose yield reached 29.99%.H+could catalyze the hydrolysis of cotton fiber more effectively due to damage to crystal structure and hydrogen bonds.

Separation of diaspore from bauxite by selective flocculation using hydrolyzed polyacrylamide

Selective flocculation is a new method to solve the problem of China's bauxite de-silication besides flotation and reverse flotation. The method of selective flocculation of bauxite using hydrolyzed polyacrylamide as flocculant was experimented and evaluated. The results of diaspore and kaolinite single mineral settling tests show that the difference between settlement yield of kaolinite(settling 15 min) and diaspore(settling 3 min) increases from 16% to 60% by adding flocculant at pH=7. Results of selective flocculation experiment of bauxite show that the higher concentrate grade(65.75) and Al-Si ratio(7.34) could be obtained with sodium carbonate as dispersant compared with sodium hexametaphosphate; under the action of flocculating agent, the concentrate grade and Al-Si ratio increase to 67.99 and 9.01. These results could meet the requirements of Bayer production, and the simpler process was expected to cost far less than traditional flotation method and a promising de-silication method of bauxite.

Rheological properties of salt-tolerant HPAM solutions with ultrahigh molecular weight

The rheological properties of salt-tolerant partially hydrolyzed polyacrylamide(HPAM)solutions with molecular of 2.5×107 g/mol at different concentrations were measured in steady-state shear flow mode by Haake Rheostress 150 rheometer.Three constitutive equations(Oldroyd four constant model,Guesekus model and FENE-P model) were used for describing the apparent viscosity and first normal stress difference.The apparent viscosity of salt-tolerant HPAM solutions appears a first Newtonian zone when the shear rate is approximately lower than 0.2 s-1.At high shear rate,the HPAM solutions show shear-thinning and elasticity.The results show that the FENE-P model has the best agreement between theoretical and experimental data within the available shear rate range.The material parameters are useful for numerical analysis of polymer solution flow fields.

Deformation of Linked Polymer Coils

Linked polymer solution (LPS) is defined as the solution of linked polymer coils (LPCs) dispersed in water, composed of low concentration partially hydrolyzed polyacrylamide (HPAM) and aluminum citrate (crosslinker). In the work, the conformational changes of LPCs under different conditions were investigated by the methods of membrane filtering under low pressure, dynamic light scattering and core flooding experiments. The results showed that in some conditions the LPCs could be compressed mechanically to 1/158.5 of their original volume because of relatively lower HPAM cross-linking. The hydration property of LPCs was similar to that of normal polymer coils. The deformation of LPCs was more restricted than that of ordinary polymer coils under the flow shear stress or the shift of hydration equilibrium caused in the variation of the electrolyte concentration which is responsible for the effective plugging in the throats of porous media when LPCs are used for deep diverting.