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Copyright of Journal of Agricultural Science & Technology (1008-0864) is the property of Journal of Agricultural Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Agricultural Science & Technology (1008-0864) is the property of Journal of Agricultural Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We conducted an experiment with five treatments in winter wheat of the dryland of Northwest China, i.e . 30 t·hm -2 cow dung (M) plus different doses of nitrogen fertilizer (0, 75, 150, 225, and 300 kg N·hm -2 ), denoted by M+N 0 , M+N 75 , M+N 150 , M+N 225 , and M+N 300 , respectively. After three years of treatment, wheat yield, grain quality, and soil biological characteristics were measured in two consecutive years (2018 and 2019). The results showed that the combination of manure with nitrogen fertilizer significantly increased wheat yield compared with the manure-only treatment (M+N 0 ). Compared with the manure-only treatment, the combined treatments significantly increased wheat grain protein content, wet gluten, sedimentation value, and extensibility, but not for starch content. Neither wheat yield nor grain quality had significant differences among the M+N 150 , M+N 225 , and M+N 300 treatments, but both were prominently higher than those of M+N 75 . Soil microbial biomass carbon (MBC) and nitrogen (MBN) reached highest in M+N 150 for both years, which were distinctly higher than those of M+N 0 , M+N 225 , and M+N 300 . In 2018, soil β-1, 4-glucosidase, cellobiohydrolase, L-leucine aminopeptidase, β-1,4-N-acetyl glucosaminidase, and alkaline phosphatase activities in M+N 150 treatment were higher than those of other treatments. In 2019, soil enzyme activities (excluding L-leucine aminopeptidase) in M+N 150 were higher than those of M+N 0 and M+N 225 . MBC significantly positively correlated with MBN, and both significantly positively correlated with the activities of cellobiohydrolase, β-1, 4-N-acetyl glucosaminidase, and alkaline phosphatase. MBN significantly positively correlated with total nitrogen content and negatively correlated with NO 3 - . Considering winter wheat yield, grain quality, and soil biological characteristics, M+N 150 was conducive to sustainable production of winter wheat in drylands of Northwest China.

Deficient activity of endo-1,4-beta-glucanase II (Cel5A) secreted by Trichoderma reesei is one of the challenges involved in effective cellulase saccharification of cellulosic substrates. Therefore, we expressed Cel5A in Pichia pastoris by constructing a recombinant strain. With the gene optimization based on codon bias, and the construction of expression vector pPIC9K-eg2, the optimized gene was electro-transformed into P. pastoris GS115 to form transformants. Then, a high Cel5A activity producing recombinant, namely P. pastoris GS115-EG Ⅱ, was selected on G-418 resistant plates, followed by shake-flask cultivation. Enzyme characterization showed that the recombinant Cel5A reacted optimally at pH 4.5 and 60 ℃, with 50 kDa of molecular weight, preferentially degrading amorphous cellulose. Recombinant Cel5A was not significantly different from the native T. reesei Cel5A. Moreover, a shake-flask fermentation of the recombinant strain was optimized as below: incubation temperature 28 ℃, initial pH 5.0, inoculum volume 2%, methanol addition (per 24 h) 1.5% (V/V), sorbitol addition (per 24 h) 4 g/L and Tween 80 4 g/L. Under above optimized condition, the recombinant produced 24.0 U/mL of the Cel5A after 192 h fermentation. When incubated in a 5 L fermentation, Cel5A enzyme activity reached 270.9 U/mL at 180 h, with 4.16 g/L of the total protein. The study indicates that the recombinant strain P. pastoris GS115-EG Ⅱ is extremely suitable for heterologous expression of T. reesei cellulase Cel5A. And the recombinant Cel5A can be used as an alternative to the native T. reesei Cel5A in development of a commercially relevant enzyme based biorefinery process.