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Yu T.,South-Central University for Nationalities | Anbarasan S.,Aalto University | Wang Y.,South-Central University for Nationalities | Telli K.,Aalto University | And 12 more authors.
Extremophiles | Year: 2016

The gene of Thermotoga maritima GH10 xylanase (TmXYN10B) was synthesised to study the extreme limits of this hyperthermostable enzyme at high temperatures in the presence of biomass-dissolving hydrophilic ionic liquids (ILs). TmXYN10B expressed from Pichia pastoris showed maximal activity at 100 °C and retained 92 % of maximal activity at 105 °C in a 30-min assay. Although the temperature optimum of activity was lowered by 1-ethyl-3-methylimidazolium acetate ([EMIM]OAc), TmXYN10B retained partial activity in 15–35 % hydrophilic ILs, even at 75–90 °C. TmXYN10B retained over 80 % of its activity at 90 °C in 15 % [EMIM]OAc and 15–25 % 1-ethyl-3-methylimidazolium dimethylphosphate ([EMIM]DMP) during 22-h reactions. [EMIM]OAc may rigidify the enzyme and lower Vmax. However, only minor changes in kinetic parameter Km showed that competitive inhibition by [EMIM]OAc of TmXYN10B is minimal. In conclusion, when extended enzymatic reactions under extreme conditions are required, TmXYN10B shows extraordinary potential. © 2016 The Author(s)

Gong M.,Nanchang University | Gong M.,Jiangxi Science and Technology Normal University | Liu J.,Jiangxi Science and Technology Normal University | Zhan Z.,Wuhan Sunhy Biology Co. | And 2 more authors.
Journal of Food, Agriculture and Environment | Year: 2012

The objective of the study was to investigate the mechanism how dietary wheat with arabinoxylanase supplementation affected the growing performances of weaned pigs. In this experiment, 32-28 day old male pigs with approximately 7.74±1.03 kg initial body weight were divided into four dietary treatment groups randomly. Four groups; control group (basic diet), low-dose group (basic diet+0.5 g enzyme/kg wheat), middle-dose group (basic diet+1.0 g enzyme/kg wheat) and high-dose group (basic diet+1.5 g enzyme/kg wheat) were fed for 12, 24 and 30 days. Eventually intestinal villus length, crypt depth, intestinal epithelial columnar cell lymphocyte count and the number of goblet cells were tested. The results from the experiment showed that the jejunum villus length value of the middle jejunum in the control group was maximal, it was significantly different with that of the low-dose and middle-dose groups (P<0.05). The villus length value and the crypt depth value of terminal ileum in low dose group were higher than that of the middle and high-dose groups, which were significantly different (P<0.05). The number of lymphocytes on the intestinal epithelium of the terminal ileum in the control group was higher than that of the middle and high-dose groups, which was also significantly different (P<0.05). The number of goblet cells and lymphocytes on the intestinal epithelium in the control group and the low-dose group for the terminal ileum was higher obviously than in the middle jejunum; there were significant differences between groups (P<0.05). With the age increasing, the ratio of villus length and the crypt depth was amplifying in both middle jejunum and the terminal ileum. In conclusion, dietary wheat with arabinoxylanase could reduce the stimulation of nonstarch polysaccharides (NSP) on intestinal tract of weaned pigs. Intraepithelial lymphocytes and goblet cells were mainly distributed in the ileum, the intestinal absorption function increased ceaselessly over time.

Shengping W.,Hunan Agricultural University | Shengping W.,CAS Institute of Subtropical Agriculture | Fang J.,Hunan Agricultural University | Xiangshan T.,CAS Institute of Subtropical Agriculture | And 8 more authors.
Journal of Animal and Veterinary Advances | Year: 2012

NSP is the major factor introducing a low digestibility of cottonseed meal in piglets. The pre study was conducted to determine the effect of NSP enzyme on the nutrient digestibility of weaned piglets a cottonseed meal-based diets. About 15 weaned piglets (14±1.4kg) were selected and ileal fistula surgery done to determine the DE, CP, DM and NSP's apparent digestibility. The results indicated that NSP enz improved piglet's apparent digestibility (p<0.05) in varying degrees; pectinase resulted in obvious degrada of the cell wall and increased piglets' DE (26.69%) andCP of ileal digesta (20.33%) and compound enzyme better in improving cottonseed meal based diets than single enzyme. © Medwell Journals, 2012.

Liu Z.,Hunan Agricultural University | Li T.,Chinese Academy of Sciences | Yin F.,Chinese Academy of Sciences | Wang S.,Chinese Academy of Sciences | And 4 more authors.
Journal of Food, Agriculture and Environment | Year: 2013

Two experiments were conducted to select the optimal levels of either a single or a combination of two or three non-starch polysaccharides (NSP) degrading enzymes for NSP degradation in a selected cottonseed meal (protein content of which is low, collected from Xinjiang, China). In Exp. 1, the cottonseed meal was incubated with different levels of NSP-degrading enzymes, including xylanase, mannanase, glucanase and pectinase, at 40°C for 2 h in quadruplicates to measure the in vitro digestibility of NSP fractions. In Exp. 2, nine ileal cannulated pigs with an average body weight of 16 (SD 1.41) kg were assigned to nine dietary treatments in a 9 × 9 Latin square design. Diets were prepared by adding either a single or a combination of NSPdegrading enzymes at the appropriate level determined in Exp.1. Diets were fed for five days followed by a 24 h ileal digesta collection period for determining the apparent ileal digestibility (AID) of dry matter, energy, crude protein, and NSP fractions. Total NSP contents in the selected grains and other agricultural by-products were relatively low (less than 14%), except for that of barley (sample ID C-4); however, that in other agricultural by-products were relatively high, and some even up to 49.9% (for example palm kernel meal, sample ID T-4). The content of water-soluble nonstarch polysaccharides (WSNSP) was lower than that of water-insoluble NSP in all the tested feed ingredients. The monosaccharide contents were variable among feed sources and origins. The optimal levels of NSP-degrading enzymes per kg of sample for in vitro degradation of water-soluble and total NSP in the selected cottonseed meal were: xylanase (1000 U/kg), mannase (6000 U/kg), glucanase (2000 U/kg) and pectinase (3000 U/kg), respectively. The AID of dry matter, gross energy, crude protein, total WSNSP, arabinose and galactose in pectinase-supplemented (3000 U/kg) diet were higher (P < 0.05) than in control and in diets supplemented with xylanase, mannanase or glucanase. Collectively, dietary supplementation with NSP-degrading enzymes could effectively degrade dietary WSNSP and total NSP and therefore improve the digestibility of main nutrients and NSP fractions, and such function of pectinase was even better than that of combination of NSP-degrading enzymes in pigs.

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