The Optimal Culture Condition Of Hydrogen Production Bacteria And The Research Of The Measured Condition Of DHA

Bio-hydrogen production was paid attention to its advantages,anaerobic fermentation hydrogen production has the advantages of high hydrogen production capacity,stable hydrogen production and et al.A hydrogen producing bacterium was isolated from the CSTR,and was termed as Pectinatus sp.L6.Batch culture for fermentation hydrogen production of hydrogen producing bacteria L6 were examined with cultured temperature,and the hydrogen producing bacteria L6 was researched in five cultured temperature,including pH value,dry weight,terminal aqueous productions.The determination condition and cultured temperature of DHA was researched simultaneously.The results show that the optimal culture temperature was 35℃,and the order of culture temperature of hydrogen production capacity was as follow:30℃ 40℃,25℃,45℃.Under the temperature of 35℃ condition,The maximum biogas production rate and hydrogen production rate of hydrogen producing bacteria L6 was 84.7mL/h and 72.1mL/(L-h)at 33h,respectively.The maximum increment of dry weight per unit time was 579mg/L at 40h.The pH value was declined to 4.37 at 12h from the initial 6.13,and was stabilized to 4.45 at 64h.The order of percentage of the terminal aqueous productions was as follow:butyric acid,acetic acid,propionic acid and ethanol.The maximum percentage of butyric acid was 86.1%at 28h,and at the same time the percentage of acetic acid,propionic acid,ethanol was 8.3%、3.9%,1.3%,respectively.The fermentation type was butyric acid type.The rules of biogas production rate,hydrogen production rate,pH value,dry weight and terminal aqueous productions at other temperatures was similar with 35℃.But the hydrogen producting was the best at 35℃.At 30℃,40℃,25℃ and 45℃ the maximum hydrogen production rate was 59.0mL/(L·h),51.0mL/(L·h),31.8mL/(L·h),23.9mL/(L-h),respectively.The TTC-DHA method was choosed by comparing with the four measured methods of DHA.The results show that the optimum conditions of TTC-DHA were as follow:the centrifugal revolving speed was 6000rpm,the centrifugal time was 10min,the maximum absorption peak was at the point of 480nm,the bath temperature was 35℃,the reaction time was 4h,the extraction time was 10min,the optimal addition of extractant was 5mL,the reducing time of the standard curve of TTC-DHA method was 10 minutes,and the best dosage of Tris-HCl(pH=8.4),TTC,Na2SO3(0.36%)and Na2S2O4 was 2mL,2mL,1mL and 5mg.The order of culture temperature of DHA was as follow:30℃,40 ℃,25 ℃,45 ℃.The DHA of hydrogen producing bacteria L6 increased with increasing hydrogen production capacity and the DHA was the highest at 35℃.The increasing period,the stable period and the decreasing period of DHA was 0-24h,28-48h,52-64h,respectively.The initial TF value was 27mg/L,and the maximum TF value was 133mg/L at 32h,and declined to 94mg/L at 64h.