1.Determination of troxerutinum and coumarin in Keyanzhong Tablets by HPCE
Han QIU ; Sujian CHEN ; Feiyun YE ;
Chinese Traditional Patent Medicine 1992;0(11):-
Objective: To determine troxerutinum and coumarin in Keyanzhong Tablets. Methods: A HPCE method is used. Ibuprofen is used as internal standard with the running buffer of 25 mmol?L -1 borax boric acid (pH9.2),containing 30 mmol?L -1 SDS and 10% acetonitrile. The running voltage is 20KV, at the detection wavelength of 214nm.Results: The linear ranges of Troxerutinum and Coumarin are 50 250?g?mL -1 ( r = 0.9991 ) and 25 125?g?mL -1 ( r =0.9993),respectively. The average recoveries are 98.4% and 98.8%, respectively. RSD are 1.6% and 2.0% ( n =5),respectively.Conclusion: The method is simple, accurate and sensible, and can be used for quality control of the preparation.
2.Manipulation of isocitrate dehydrogenase genes affects the anti-autolytic ability of lager yeast.
Kejia YE ; Haobo WU ; Chunfeng LIU ; Chengtuo NIU ; Feiyun ZHENG ; Qi LI ; Jinjing WANG
Chinese Journal of Biotechnology 2023;39(8):3451-3463
Yeast autolysis affects the flavor and quality of beer. The regulation of yeast autolysis is a need for industrial beer production. Previous studies on brewer's yeast autolysis showed that the citric acid cycle-related genes had a great influence on yeast autolysis. To explore the contribution of isocitrate dehydrogenase genes in autolysis, the IDP1 and IDP2 genes were destroyed or overexpressed in typical lager yeast Pilsner. The destruction of IDP1 gene improved the anti-autolytic ability of yeast, and the anti-autolytic index after 96 h autolysis was 8.40, 1.5 times higher than that of the original strain. The destruction of IDP1 gene increased the supply of nicotinamide adenine dinucleotide phosphate (NADPH) and the NADPH/NADP+ ratio was 1.94. After fermentation, intracellular ATP level was 1.8 times higher than that of the original strain, while reactive oxygen species (ROS) was reduced by 10%. The destruction of IDP2 gene resulted in rapid autolysis and a decrease in the supply of NADPH. Anti-autolytic index after 96 h autolysis was 4.03 and the NADPH/NADP+ ratio was 0.89. After fermentation, intracellular ATP level was reduced by 8% compared with original strain, ROS was 1.3 times higher than that of the original strain. The results may help understand the regulation mechanism of citric acid cycle-related genes on yeast autolysis and provide a basis for the selection of excellent yeast with controllable anti-autolytic performance.
Humans
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Isocitrate Dehydrogenase/genetics*
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NADP
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Reactive Oxygen Species
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Autolysis
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Adenosine Triphosphate