Xylo-oligosaccharides preparation through acid hydrolysis of hemicelluloses isolated from press-lye

The preparation of xylo-oligosaccharides(XOSs)through hydrolysis of hemicelluloses was studied.The hemicelluloses were isolated from the press lye discharged in the production of viscose,which contained about 30%xylan.Then,a factorial experimental design was applied to compare the influences of several factors including the concentrations of sulphuric acid and hemicelluloses,the duration and temperature of the hydrolysis,on the conversion of xylan,and the selectivity for the product–XOSs.The results showed that the hydrolysis duration affects the yield of XOSs to the greatest extent.It is difficult to obtain a high yield of XOSs with sulphuric acid as the hydrolysis catalyst.

Separation of xylo-oligosaccharides from enzymatic hydrolytes using membrane reactor

The time course of xylo-oligosaccharides concentration and xylo-oligosaccharides yield in the separation of xylo-oligosaccharides from enzymatic hydrolytes was studied using a membrane reactor with constant permeate flux of 4 L·m -2 ·h -1 . The results show that xylanases retain 90% of its activity in the reactor. The concentration of xylo-oligosaccharides achieves the maximum, about 5.48 g/L in 30 min. The difference of xylo-oligosaccharides in the retentate and permeate stream is low, <0.62 g/L, therefore it can permeate through membrane. Under the operating conditions that xylan concentration is 30.0 g/L, pH 5.0, operating pressure 16 kPa, temperature 48 ℃, feed velocity 400 mL/min, reaction volume 400 mL, enzyme dosage 10%(volume fraction), dilution rate 1 h -1 , and enzymatic hydrolysis time 195 min, the yield of xylo-oligosaccharides reaches 31.69%.

Effectiveness of dietary xylo-oligosaccharides for broilers fed a conventional corn-soybean meal diet

An experiment was conducted to investigate the effect of dietary supplementation of xylo-oligosaccharides（XOS） on growth performance, meat quality, immune functions, duodenal morphology and intestinal microbial populations of broilers fed a conventional corn-soybean meal basal diet. A total of 450 1-day-old commercial Arbor Acres male broiler chicks were randomly allocated by bodyweight to 1 of 5 treatments with 6 replicate cages（15 broilers per cage） for each of 5 treatments in a completely randomized design. Chicks were fed the basal corn-soybean meal diets supplemented with 0, 25, 50, 75, or 100 mg of XOS kg–1 of diet, respectively, for an experimental duration of 42 days. The results showed that supplementation of XOS affected feed conversion rate（feed/gain, F/G） during days 22–42 and 1–42（P〈0.03）, drip loss in thigh muscle（P=0.02）, and duodenal crypt depth（P=0.005） on day 42, but had no effect（P〉0.05） on all other measured indices. The chicks fed the diet supplemented with 100 mg of XOS kg–1 had the lowest（P〈0.05） F/G and drip loss in thigh muscle. The drip loss in thigh muscle decreased linearly（P=0.003） as the supplemented XOS increased. Duodenal crypt depth decreased（P〈0.05） at the supplemental level of 75 mg of XOS kg–1. The results indicate that dietary supplementations of 75 and 100 mg of XOS kg–1 are beneficial to broilers fed a conventional corn-soybean meal diet.

Effects of xylanase,protease,and xylo-oligosaccharides on growth performance,nutrient utilization,short chain fatty acids,and microbiota in Eimeria-challenged broiler chickens fed high fiber diet

A 21-d experiment was conducted to study the effect of xylanase,protease,and xylo-oligosaccharides on growth performance,nutrient utilization,gene expression of nutrient transporters,cecal short-chain fatty acids(SCFA),and cecal microbiota profile of broilers challenged with mixed Eimeria spp.The study utilized 392 zero-d-old male broiler chicks allocated to 8 treatments in a 4×2 factorial arrangement,as follows:corn-soybean meal diet with no enzyme(Con);Con plus xylanase alone(XYL);Con plus xylanase combined with protease(XYL+PRO);or Con plus xylo-oligosaccharides(XOS);with or without Eimeria challenge.Diets were based on a high-fiber(100 g/kg soluble fibers and 14 g/kg insoluble fibers)basal diet.At d 15,birds in challenged treatment were gavaged with a solution containing Eimeria maxima,Eimeria acervulina,and Eimeria tenella oocysts.At d 21,birds were sampled.Eimeria depressed(P<0.01)growth performance and nutrient utilization,whereas supplementation had no effect.There were significant Eimeria×supplementation interactions for the sugar transporters GLUT5(P=0.02),SGLT1(P=0.01),SGLT4(P<0.01),and peptide transporter PepT1(P<0.01)in jejunal mucosa.Eimeria challenge increased the expression of GM-CSF2(P<0.01)and IL-17(P=0.04)but decreased(P=0.03)IL-1βexpression in the cecal tonsil.Eimeria×supplementation interactions for cecal acetate,butyrate,and total SCFA showed that concentrations increased or tended to be greater in the supplemented treatments,but only in non-challenged birds.Birds challenged with Eimeria spp.had higher concentrations of isobutyrate(P<0.01),isovalerate(P<0.01),and valerate(P=0.02)in cecal content.Eimeria challenge significantly(P<0.01)decreased the microbial richness and diversity,and increased(P<0.01)the proportion of Anaerostipes butyraticus,Bifidobacterium pseudolongum,and Lactobacillus pontis.In conclusion,Eimeria infection depressed growth performance,nutrient utilization with regulating nutrient transporters.Furthermore,Eimeria challenge shifted the microbial profile and reduced microbial richness and diversity.On the other hand,enzyme supplementation showed limited benefits,which included increased concentrations of SCFA.

Dietary xylo‑oligosaccharides and arabinoxylans improved growth efficiency by reducing gut epithelial cell turnover in broiler chickens

Background One of the main roles of the intestinal mucosa is to protect against environmental hazards.Supple-mentation of xylo-oligosaccharides(XOS)is known to selectively stimulate the growth of beneficial intestinal bacteria and improve gut health and function in chickens.XOS may have an impact on the integrity of the intestinal epithelia where cell turnover is critical to maintain the compatibility between the digestive and barrier functions.The aim of the study was to evaluate the effect of XOS and an arabinoxylan-rich fraction(AXRF)supplementation on gut func-tion and epithelial integrity in broiler chickens.Methods A total of 128 broiler chickens(Ross 308)were assigned into one of two different dietary treatments for a period of 42 d:1)control diet consisting of a corn/soybean meal-based diet;or 2)a control diet supplemented with 0.5%XOS and 1%AXRF.Each treatment was randomly distributed across 8 pens(n=8)with 8 chickens each.Feed intake and body weight were recorded weekly.On d 42,one male chicken per pen was selected based on aver-age weight and euthanized,jejunum samples were collected for proteomics analysis.Results Dietary XOS/AXRF supplementation improved feed efficiency(P<0.05)from d 1 to 42 compared to the con-trol group.Proteomic analysis was used to understand the mechanism of improved efficiency uncovering 346 dif-ferentially abundant proteins(DAP)(Padj<0.00001)in supplemented chickens compared to the non-supplemented group.In the jejunum,the DAP translated into decreased ATP production indicating lower energy expenditure by the tissue(e.g.,inhibition of glycolysis and tricarboxylic acid cycle pathways).In addition,DAP were associated with decreased epithelial cell differentiation,and migration by reducing the actin polymerization pathway.Put-ting the two main pathways together,XOS/AXRF supplementation may decrease around 19%the energy required for the maintenance of the gastrointestinal tract.Conclusions Dietary XOS/AXRF supplementation improved growth efficiency by reducing epithelial cell migration and differentiation(hence,turnover),actin polymerization,and consequently energy requirement for maintenance of the jejunum of broiler chickens.

Xylo-Oligosaccharide Preparation through Enzyme Hydrolysis of Hemicelluloses Isolated from Press Lye

The emerging food additive, xylo-oligosaccharide(XOSs), was prepared through enzymatic hydrolysis of hemicelluloses isolated from press lye. Two of the three experimental enzyme preparations presented favourable effects, while the other one consisting of the nominal enzyme preparations with high enzyme activity was found to have poor catalytic effects. The conversion of xylan exceeded 40% and the selectivity for XOSs reached 90% when the temperature, hemicellulose concentration, dosage of enzymes, and hydrolysis time were 40?C, 100 g/L, 1 ku/g, and 4 h, respectively. Xylo-oligosaccharide preparation through enzymatic hydrolysis of hemicelluloses isolated from press lye was proved to be a feasible process to utilize the by-product of the lye regeneration, which will substantially improve the economy of the lye regeneration and recycling.