1.Effects of carbon and nitrogen sources on 5-keto-gluconic acid production.
Zhilei TAN ; Hongcui WANG ; Yuqiao WEI ; Yanyan LI ; Cheng ZHONG ; Shiru JIA
Chinese Journal of Biotechnology 2014;30(1):76-82
Gluconobacter oxydans is known to oxidize glucose to gluconic acid (GA), and subsequently, to 2-keto-gluconic acid (2KGA) and 5-keto-gluconic acid (5KGA), while 5KGA can be converted to L-(+)-tartaric acid. In order to increase the production of 5KGA, Gluconobacter oxydans HGI-1 that converts GA to 5KGA exclusively was chosen in this study, and effects of carbon sources (lactose, maltose, sucrose, amylum and glucose) and nitrogen sources (yeast extract, fish meal, corn steep liquor, soybean meal and cotton-seed meal) on 5KGA production were investigated. Results of experiment in 500 mL shake-flask show that the highest yield of 5KGA (98.20 g/L) was obtained using 100 g/L glucose as carbon source. 5KGA reached 100.20 g/L, 109.10 g/L, 99.83 g/L with yeast extract, fish meal and corn steep liquor as nitrogen source respectively, among which the optimal nitrogen source was fish meal. The yield of 5KGA by corn steep liquor is slightly lower than that by yeast extract. For the economic reason, corn steep liquor was selected as nitrogen source and scaled up to 5 L stirred-tank fermentor, and the final concentration of 5KGA reached 93.80 g/L, with its maximum volumetric productivity of 3.48 g/(L x h) and average volumetric productivity of 1.56 g/(L x h). The result obtained in this study showed that carbon and nitrogen sourses for large-scale production of 5KGA by Gluconobacter oxydans HGI-1 were glucose and corn steep liquor, respectively, and the available glucose almost completely (85.93%) into 5KGA.
Bioreactors
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Carbon
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chemistry
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Culture Media
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chemistry
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Fermentation
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Gluconates
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metabolism
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Gluconobacter oxydans
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metabolism
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Industrial Microbiology
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Nitrogen
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chemistry
2.Thoughts on fund compensation of adverse events following immunization in China
Ting SU ; Zhilei ZHONG ; Dan YOU ; Litao RUAN ; Shengran YANG ; Qian LI ; Qiuyu CHEN ; Zexu YU ; Cheng LI
Shanghai Journal of Preventive Medicine 2022;34(4):382-387
After the promulgation and implementation of the Vaccine Administration Law of the People’s Republic of China, the compensation of suspected adverse reactions in China is to be reformed and innovated. There have been attempts at compensation through government finance and insurance, but there has been no precedent for a fund of vaccine-related compensation in China, which means that this could be a new method of solving disputes of compensation for vaccine-related incidences and enhancing public confidence in vaccination. It is suggested that under the current system, we can select a province as a pilot to explore the fund compensation mechanism. The fund comes from special financial allocation, special taxation of vaccine enterprises, fund investment income, charitable donation and other channels. Through a special fund management organization, the independent identification and compensation process can be realized, so as to shorten the current compensation procedure, improve the amount of compensation, ultimately protect the interests of all parties, and promote the steady development of vaccination.