two-stage co-culture approach was employed in an acetone-butanol-ethanol(ABE)fermentation.An obligate aerobic bacterium,Arthrobacter sp.,was first grown for 6 h at 30℃ to create anaerobic conditions.Subsequently,Clos...two-stage co-culture approach was employed in an acetone-butanol-ethanol(ABE)fermentation.An obligate aerobic bacterium,Arthrobacter sp.,was first grown for 6 h at 30℃ to create anaerobic conditions.Subsequently,Clostridium beijerinckii TISTR 1461 was inoculated and a fermentation was performed at 37℃.To identify an intermediate temperature suitable for both microorganisms,their growth was examined at 30,34,and 37℃.C.beijerinckii exhibited the highest specific growth rate at 37℃,while Arthrobacter sp.displayed similar growth rates at all tested temperatures.Butanol production from a synthetic medium(P2 medium)by C.beijerinckii at different temperatures using oxygen-free nitrogen(OFN)gas flushing as a control treatment revealed that fermentation at 37℃ gave the highest butanol concentration(PB,9.98 g/L).Consequently,37℃ was chosen for butanol production from sweet sorghum stem juice(SSJ)by co-culture of these two microorganisms in 1-L screw-capped bottles.Compared to the control treatment,higher PB(11.38 g/L),yield(Y_(B/S),0.37 g/g)and productivity(Q_(B),0.24 g/L⋅h)were achieved using the co-culture system.These results were further confirmed by monitoring the oxidation-reduction potential(ORP)during ABE fermentation in a 2-L stirred-tank bioreactor(STR).Moreover,when the co-culture fermentation at 37℃ was scaled up in a 30-L STR,the PB,Y_(B/S)and Q_(B)values were comparable to those obtained in the 2-L STR.Therefore,co-culture fermentation of Arthrobacter sp.and C.beijerinckii TISTR 1461 at 37℃ represents a promising method for large-scale butanol production.展开更多
基金supported by the Fundamental Fund 2023 of Khon Kaen Universitysupport from the National Science,Research and Innovation Fund(NSRF),Thailand(Grant.No.179509).
文摘two-stage co-culture approach was employed in an acetone-butanol-ethanol(ABE)fermentation.An obligate aerobic bacterium,Arthrobacter sp.,was first grown for 6 h at 30℃ to create anaerobic conditions.Subsequently,Clostridium beijerinckii TISTR 1461 was inoculated and a fermentation was performed at 37℃.To identify an intermediate temperature suitable for both microorganisms,their growth was examined at 30,34,and 37℃.C.beijerinckii exhibited the highest specific growth rate at 37℃,while Arthrobacter sp.displayed similar growth rates at all tested temperatures.Butanol production from a synthetic medium(P2 medium)by C.beijerinckii at different temperatures using oxygen-free nitrogen(OFN)gas flushing as a control treatment revealed that fermentation at 37℃ gave the highest butanol concentration(PB,9.98 g/L).Consequently,37℃ was chosen for butanol production from sweet sorghum stem juice(SSJ)by co-culture of these two microorganisms in 1-L screw-capped bottles.Compared to the control treatment,higher PB(11.38 g/L),yield(Y_(B/S),0.37 g/g)and productivity(Q_(B),0.24 g/L⋅h)were achieved using the co-culture system.These results were further confirmed by monitoring the oxidation-reduction potential(ORP)during ABE fermentation in a 2-L stirred-tank bioreactor(STR).Moreover,when the co-culture fermentation at 37℃ was scaled up in a 30-L STR,the PB,Y_(B/S)and Q_(B)values were comparable to those obtained in the 2-L STR.Therefore,co-culture fermentation of Arthrobacter sp.and C.beijerinckii TISTR 1461 at 37℃ represents a promising method for large-scale butanol production.
