The objective of this work is to investigate the fermentation capacity and metabolic characteristics of a novel strain of bacteria B49 isolated from anaerobic activated sludge. The examination was conducted in batch c...The objective of this work is to investigate the fermentation capacity and metabolic characteristics of a novel strain of bacteria B49 isolated from anaerobic activated sludge. The examination was conducted in batch culture at 35 ℃. The results showed that the carbon flow gave priority to the production of ethanol, and yield of ethanol is always greater than that of acetic acid. The hydrogen and ethanol occurred simultaneously. The exponential phase of the B49's cell growth was from 12 to 22 h. Evolution of hydrogen appeared to start after the exponential phase of cell growth and reach maximum production at the early stationary phase. The rate of hydrogen production reached a maximum of 16.8 mL/h, and the percentage of hydrogen gas in the headspace of serum bottle obtained a maximum of 41 % at 22 h. The B49 was able to grow using molasses as substrate for cell growth. When the molasses was used as substrate, maximum yield of hydrogen was obtained 2460 mL/L culture at 2 % (V/V) of molasses. The hydrogen yield was increased to 3060 mL/L culture after addition of 0.5 g/L of yeast extract in the molasses medium and the yield of hydrogen was increased by 24.4%.展开更多
The efficiency of using nanostructured silver in technological processes of making red wine has been studied with the purpose of substituting sulfur dioxide. For preparation of research objects, we used dry wine mater...The efficiency of using nanostructured silver in technological processes of making red wine has been studied with the purpose of substituting sulfur dioxide. For preparation of research objects, we used dry wine material of red grape variety ＂Saperavi＂. After completion of malolactic fermentation, the second racking the wine material off the lees and its treatment with antiseptics were carried out. Sulfur dioxide （Kadifit） and different doses of nanostructured silver were used. Microbiological investigation was performed on the presence of lactic bacteria after completion of malolactic fermentation and racking off the lees. The investigation of phenolic compounds was conducted at the following stages of technological processes： （1） after completion of alcoholic fermentation and racking off the lees; （2） after completion of malolactic fermentation; （3） after the second racking off the lees and treatment with antiseptics. By means of the HPLC analysis, the amounts ofcatechins, phenolcarbonic acids and flavonols were determined. It has been established that after conduction of malolactic fermentation in the process of racking the wine material off the lees and storage, the application of 0.6 mg/L of nano-silver for blocking of lactic-acid bacteria and inhibition of oxidation of phenolic compounds has the same effect as sulfitization with 50 mg/L of Kadifit.展开更多
To explore the mechanism of the inhibition of HIV-1 by Mycoplasma fermentans, culture supernatants and thallodic proteins from M.fermentans PG18 were prepared and the protein components of the supernatants were purifi...To explore the mechanism of the inhibition of HIV-1 by Mycoplasma fermentans, culture supernatants and thallodic proteins from M.fermentans PG18 were prepared and the protein components of the supernatants were purified with high performance liquid chromatography (HPLC).The inhibitory activities to reverse transcriptase (RT) and the nuclease activities were detected; the influence of M.fermentans on IL-10 secretion by both normal and HIV-1 infected human PBMC were determined, and the inhibitory effect of rhIL-10 on HIV-1 replication was detected with ELISA method. The results showed that the purified proteins with a molecular weight of 67-100 kDa or 10-25 kDa showed a 36% or 34% in hibitory activity to RT and partial nuclease activity. The thallodic protein could induce both normal and HIV-1 infected PBMC to secret IL-10 remarkably, and to the latter, this effect was more apparent. While rhIL-10 could inhibit replication of HIV-1 in PBMC in vitro in a dose-dependant manner. It concludes that the inhibitory effect of the M.fermentans PG18 culture supernatants on RT and the promoting effect of PG18 thallodic protein on IL-10 secretion in PBMC explain the mechanisms of inhibition to HIV-1 by M.fermentans PG18.展开更多
基金the National Natural Science Fundation of China(Grant No.30470054)
文摘The objective of this work is to investigate the fermentation capacity and metabolic characteristics of a novel strain of bacteria B49 isolated from anaerobic activated sludge. The examination was conducted in batch culture at 35 ℃. The results showed that the carbon flow gave priority to the production of ethanol, and yield of ethanol is always greater than that of acetic acid. The hydrogen and ethanol occurred simultaneously. The exponential phase of the B49's cell growth was from 12 to 22 h. Evolution of hydrogen appeared to start after the exponential phase of cell growth and reach maximum production at the early stationary phase. The rate of hydrogen production reached a maximum of 16.8 mL/h, and the percentage of hydrogen gas in the headspace of serum bottle obtained a maximum of 41 % at 22 h. The B49 was able to grow using molasses as substrate for cell growth. When the molasses was used as substrate, maximum yield of hydrogen was obtained 2460 mL/L culture at 2 % (V/V) of molasses. The hydrogen yield was increased to 3060 mL/L culture after addition of 0.5 g/L of yeast extract in the molasses medium and the yield of hydrogen was increased by 24.4%.
文摘The efficiency of using nanostructured silver in technological processes of making red wine has been studied with the purpose of substituting sulfur dioxide. For preparation of research objects, we used dry wine material of red grape variety ＂Saperavi＂. After completion of malolactic fermentation, the second racking the wine material off the lees and its treatment with antiseptics were carried out. Sulfur dioxide （Kadifit） and different doses of nanostructured silver were used. Microbiological investigation was performed on the presence of lactic bacteria after completion of malolactic fermentation and racking off the lees. The investigation of phenolic compounds was conducted at the following stages of technological processes： （1） after completion of alcoholic fermentation and racking off the lees; （2） after completion of malolactic fermentation; （3） after the second racking off the lees and treatment with antiseptics. By means of the HPLC analysis, the amounts ofcatechins, phenolcarbonic acids and flavonols were determined. It has been established that after conduction of malolactic fermentation in the process of racking the wine material off the lees and storage, the application of 0.6 mg/L of nano-silver for blocking of lactic-acid bacteria and inhibition of oxidation of phenolic compounds has the same effect as sulfitization with 50 mg/L of Kadifit.
基金This study was supported by a grant from the National Natural Science Foundation of China (No. 39770678)
文摘To explore the mechanism of the inhibition of HIV-1 by Mycoplasma fermentans, culture supernatants and thallodic proteins from M.fermentans PG18 were prepared and the protein components of the supernatants were purified with high performance liquid chromatography (HPLC).The inhibitory activities to reverse transcriptase (RT) and the nuclease activities were detected; the influence of M.fermentans on IL-10 secretion by both normal and HIV-1 infected human PBMC were determined, and the inhibitory effect of rhIL-10 on HIV-1 replication was detected with ELISA method. The results showed that the purified proteins with a molecular weight of 67-100 kDa or 10-25 kDa showed a 36% or 34% in hibitory activity to RT and partial nuclease activity. The thallodic protein could induce both normal and HIV-1 infected PBMC to secret IL-10 remarkably, and to the latter, this effect was more apparent. While rhIL-10 could inhibit replication of HIV-1 in PBMC in vitro in a dose-dependant manner. It concludes that the inhibitory effect of the M.fermentans PG18 culture supernatants on RT and the promoting effect of PG18 thallodic protein on IL-10 secretion in PBMC explain the mechanisms of inhibition to HIV-1 by M.fermentans PG18.
