Kluyveromyces marxianus KD-15,called flex yeast,is a strain that is insensitive to catabolite
repression and has the capacity to produce ethanol efficiently from a mixture of beet
molasses and whey powder.When a fermentation test was conducted in 50 mL of
a medium containing 200 mg mL1 of sugar as sugar beet thick juice diluted with an
arbitrary amount of crude whey,strain KD-15 produced over 99 mg mL1 ethanol in all the
media tested,and ethanol formation decreased in proportion to the volume of whey by K.
marxianus NBRC 1963,the parental strain of KD-15,and Saccharomyces cerevisiae NBRC 0224,
the reference strain for conventional ethanol production.Fermentation of thick juice
diluted with whey alone by strain KD-15 at 30 C initially proceeded slower than that at
33 Ce 37 C but finally bore the highest level of ethanol.The maximum ethanol concen-
tration obtained in1.5 Lof a medium using a 2-L fermentor was elevated by aeration of
15 e 50 mL min 1 and reduced by that in excess of 100 mL min1. Under optimized condi-
tions in 72 h,strain KD-15 converted all of the sugars derived from thick juice and whey to
ethanol at 102 mg mL1, corresponding to 92.9 % of the theoretical yield.
Kluyveromyces marxianus KD-15,called flex yeast,is a strain that is insensitive to cataboliterepression and has the capacity to produce ethanol efficiently from a mixture of beetmolasses and whey powder.When a fermentation test was conducted in 50 mL ofa medium containing 200 mg mL1 of sugar as sugar beet thick juice diluted with anarbitrary amount of crude whey,strain KD-15 produced over 99 mg mL1 ethanol in all themedia tested,and ethanol formation decreased in proportion to the volume of whey by K.marxianus NBRC 1963,the parental strain of KD-15,and Saccharomyces cerevisiae NBRC 0224,the reference strain for conventional ethanol production.Fermentation of thick juicediluted with whey alone by strain KD-15 at 30 C initially proceeded slower than that at33 Ce 37 C but finally bore the highest level of ethanol.The maximum ethanol concen-tration obtained in1.5 Lof a medium using a 2-L fermentor was elevated by aeration of15 e 50 mL min 1 and reduced by that in excess of 100 mL min1. Under optimized condi-tions in 72 h,strain KD-15 converted all of the sugars derived from thick juice and whey toethanol at 102 mg mL1, corresponding to 92.9 % of the theoretical yield.
การแปล กรุณารอสักครู่..