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Copyright of Journal of Chinese Institute of Food Science & Technology / Zhongguo Shipin Xuebao is the property of Journal of Chinese Institute of Food Science & Technology Periodical Office 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.)

To observe the therapeutic effect of intragastric administration of sodium pyruvate solution on deep Ⅱ° scald in diabetic rats and to analyze the possible mechanism. Methods Fifty male SD rats were randomly divided into the control group, model group and experimental groups 1, 2 and 3, with 10 rats in each group. The diabetic rat models were established by intraperitoneal injection of streptozotocin. After successful modeling, a deep partial thickness scald with diameter of 4 cm was inflicted on the back of each rat in the model group and the experimental groups. Rats in the experimental groups 1, 2 and 3 were given 2. 5%, 7. 5% and 10% sodium pyruvate solution by gavage, respectively, once a day, and rats in the control group and the model group were given the same amount of normal saline by gavage. On day 1, 3, 7, 14, and 21 of drug administration, the wound healing rate was observed and calculated, and the body weight and blood glucose of rats were detected. Nicotinamide adenine dinucleotide (NAD+/NADH), malondialdehyde (MDA), superoxide dismutase (SOD), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) in the wound tissues were detected by ELISA. Results The wound healing rates of the model group on day 14 and 21 of administration were lower than those of the control group, and the wound healing rate of each experimental group on day 14 and 21 of administration was higher than that of control group, and the wound healing rate of the experimental group 3 was higher than those of the experimental groups 1 and 2 (all P<0. 05). The blood glucose of the model group was higher than that of the control group at each time point of administration, and the blood glucose of each experimental group was lower than that of the model group, and that of experimental group 3 was lower than those of experimental groups 1 and 2 (all P<0. 05). The body weight of the model group was lower than that of the control group from day 3 to 21 of administration, and the body weight of each experimental group was higher than that of the model group, and the body weight of the experimental group 3 was higher than that of the experimental groups 1 and 2 from day 7 to 21 of administration (all P<0. 05). The levels of NAD+/ NADH and SOD in the wound tissues after administration in the model group were lower than those in the control group, and those in each experimental group were higher than those in the model group, and those in experimental group 3 were higher than those in experimental groups 1 and 2 (all P<0. 05). The levels of MDA, IL-6, and TNF-α in wound tissue after administration in the model group were higher than those in the control group, and those in each experimental group were lower than those in the model group, and those in experimental group 3 were lower than those in experimental groups 1 and 2 (all P<0. 05). Conclusion Intragastric administration of sodium pyruvate solution can promote wound healing, reduce blood glucose, and maintain normal body weight in diabetic rats with deep II° scald, and the mechanism may be related to inhibiting inflammatory response and peroxidation damage of wound and improving energy metabolism. [ABSTRACT FROM AUTHOR]

Objective: This paper mainly studied the effects and regulation of exogenous addition of pyruvate, overexpression of pyruvate kinase and acetyl-CoA synthase on the synthesis of Bacillomycin D. Methods: In this study, B. amyloliquefaciens fmbJ was used as the initial strain. Firstly, the effect of exogenous pyruvate with different concentrations on the yield of Bacillomycin D was detected by HPLC. The regulation of pyruvate in this process was detected by RT-PCR. Then, pyruvate kinase (pyk) and acetyl-CoA synthase (acs) overexpression strains B. amyloliquefaciens fmbJ-pyk and fmbJ-acs were constructed by electrotransformation, and their Bacillomycin D production induced by different concentrations of IPTG was studied. Results: 0.075% pyruvate could increase the yield on Bacillomycin D to 1.41-fold that of the control group. The upregulation of Bacillomycin D synthesis gene also verified this enhancement. In addition, pyruvate could up-regulate the expression of regulatory factors such as comA, comP, comQ, sigH, sigM, degU, degQ, spo0A and codY, down-regulate the expression of rapC and abrB, promote the production of acetyl CoA synthase, and finally jointly promote the synthesis of Bacillomycin D. Under the induction of 50 mg/L IPTG, the yield of Bacillomycin D of fmbJ-acs and fmbJ-pyk increased to 1.16-fold and 1.34-fold that of fmbJ, respectively. Conclusion: This study found that exogenous addition of pyruvate and overexpression of acs or pyk could promote the synthesis of Bacillomycin D, clarified the regulation of pyruvate in the synthesis of Bacillomycin D, and widened a new research idea for promoting the efficient production of Bacillomycin D.

Copyright of Storage & Process is the property of Tianjin Academy of Agricultural Sciences 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.)

Anaerobic respiration metabolism plays an essential role in the controlled atmosphere storage process of fruits and vegetables. In this study, the effects different volume fractions of CO2 (5%, 8%, 11%, and 14%) treatments on the indicators' changes including pyruvate, pyruvate decarboxylase (PDC), alcohol dehydrogenase (ADH) contents, respiration rates, ethylene release rates of garlic under 4 °C storage were investigated with the fixed O2 volume fraction of 3.5%, in order to study the effects of composite modified atmosphere packaging on anaerobic respiratory metabolic pathways and related physiology of garlic. Results indicated that during storage, the pyruvate contents of garlic decreased continuously, while the PDC and ADH activities showed an increasing trend, and the CO2 volume fractions presented significant effects on enzymes activities, especially when CO2 volume fraction exceeded 8%. The trend of ethylene release rates was similar to that of respiration rates. The peaks appeared first at low volume fractions CO2 storage, and the ethylene release and respiration intensity were continuously increased at high CO2 volume fractions. The comprehensive analysis showed that when garlic bulbs were stored at low temperature (4 °C) and 3.5% O2, the ideal ratio was that the volume fraction of CO2 was not higher than 8%. Under these conditions, the pyruvate metabolism related enzymes activities were effectively inhibited, and the accumulation of harmful substances was reduced, meanwhile the ethylene release rate and respiratory intensity were also inhibited. [ABSTRACT FROM AUTHOR]

Copyright of Storage & Process is the property of Tianjin Academy of Agricultural Sciences 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 Environmental Science & Technology (10036504) is the property of Editorial Board of Environmental 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.)

[Objectives]The purpose : of this study is to investigate the effect of zearalcnone( ZKAJon lactic acid production in Sertoli cells (SC). [Methods]The SC of Vi istar rats were cultured in vitro as test materials. 0(control), 0.1,1,10,20,30 μ.mol·L-1 ZEA were used to detect the cytotoxicity of ZKA against SC by I.DH release assay kit. The lactic acid test (lactic acid kit) was used to observe the effect of ZKA on lactic acid production in SC. The pyruvate test was performed to observe the effect of ZKA on pyruvate production in SC. The Western blot was used to detect the expression of lactic acid prodi jcing relative proteins. The immunofluorescence assay was performed aiming at detecting the key prot ein I.DH of lactic acid produc tion in SC. [Results] With the increase of ZKA concentration, the cytotoxicity of ZKA on SC gradually increased( P<0.01), and the content of lactic acid inside and outside the cell, and tl: ic concentration of pyruvate in the cell showed a downward trend (P< 0.05 or P<0.01 ). The expressions of lactic acid production-related proteins GLUT1 and I.DH exposed to ZKA at 1,10,20,30 μ.mol·L group and above significantly decreased (P<0.01), and the expression of MCT4 at the 30μmol·L-1 ZKA group significantly decreased ( P<0.05). The immunofluorescence assay showed that the fluorescence intensitv of I.DH decreased with the increase of the concentration. Compared with the control group, the protein expressions in the eells exposed to ZEA at 10,20,30 (μmol·L-1 groups, and above significantly decreased (f<0.01). [ Conclusions ] The above results indicate ZEA can inhibit the producti on of lactic acid in SC, and interfere with the energy supply of SC to germ eells, whieh damage* > the mal e reproductive function. [ABSTRACT FROM AUTHOR]

Effective utilization of xylose is a basis for economic production of biofuels or chemicals from lignocellulose biomass. Over the past 30 years, through metabolic engineering, evolutionary engineering and other strategies, the metabolic capacity of xylose of the traditional ethanol-producing microorganism Saccharomyces cerevisiae has been significantly improved. In recent years, the reported results showed that the transcriptome and metabolome profiles between xylose and glucose metabolism existed significant difference in recombinant yeast strains. Compared with glucose, the overall process of xylose metabolism exhibits Crabtree-negative characteristics, including the limited glycolytic pathway activity, which reduces the metabolic flux of pyruvate to ethanol, and the enhanced cytosolic acetyl-CoA synthesis and respiratory energy metabolism. These traits are helpful to achieve efficient synthesis of downstream products using pyruvate or acetyl-CoA as precursors. This review provides a detailed overview on the modification and optimization of xylose metabolic pathways in S. cerevisiae, the characteristics of xylose metabolism, and the construction of cell factories for production of chemicals using xylose as a carbon source. Meanwhile, the existed difficulties and challenges, and future studies on biosynthesis of bulk chemicals using xylose as an important carbon source are proposed.

To develop a high-yield pyruvate strain, we first engineered a pyruvate-producing Escherichia coli KLPP from wild-type E. coli MG1655 by blocking the pathways for byproduct formation via gene knockout. Then, we built a library of mutant containing 7 197 monoclones by using the pUT Mini-Tn5 transposon vector for random mutagenesis with E. coli KLPP. We developed a high-throughput method for pyruvate detection based on dinitrophenylhydrazine reaction using 96-well microplate reader. After two-round screening we successfully obtained six mutants with increased pyruvate titer using this method, the titer of pyruvate was increased by 38%, 31%, 19%, 28%, 44% and 14%, respectively. The position of transposon insertion was determined by whole genome re-sequencing, and the gene locus possibly influencing pyruvate production was analyzed, which laid the foundation for subsequent strain improvement by metabolic engineering.