Effect of heat pre-treatment temperature on isolation of hydrogen producing functional consortium from soil

摘要

A functional hydrogen producing consortium was isolated from soil by heat pre-treatment technique and hydrogen production at different substrate concentration was evaluated. The forest soil was heat pre-treated at 65, 80, 95, 105 and 120 ℃ temperature for 1 h. As revealed by PCR-DGGE analysis and hydrogen yield, the hydrogen producing microbial community changed with increase in heat pre-treatment temperatures giving potential hydrogen producing consortium at 95-105 ℃ soil pre-treatment. The maximum hydrogen production rate, hydrogen yield and cumulative hydrogen with 15-20 g glucose were 1390-1576 mL/L/day, 1.83-1.93 mol H_2/mol glucose, and 2966-3146 mL H_2/L, respectively. The metabolic pathways shifted from ethanol-type to acetate-formate type as soil pre-treatment temperature increased from 65 to 120 ℃. The soil heat pre-treatment approach is effective for isolating hydrogen producing natural Clostridium consortium from the soil as enumerations of the functional strains need specific temperature range to florish.