Strain improvement of Lactobacillus lactis for D-lactic acid production.
Three mutants, isolated by repeated UV mutagenesis of Lactobacillus lactis NCIM 2368, produced increased D: -lactic acid concentrations. These mutants were compared with the wild type using 100 g hydrolyzed cane sugar/l in the fermentation medium. One mutant, RM2-24, produced 81 g lactic acid/l which was over three times that of the wild type. The highest D: -lactic acid (110 g/l) in batch fermentation was obtained with 150 g cane sugar/l with a 73% lactic acid yield. The mutant utilizes cellobiose efficiently, converting it into D-lactic acid suggesting the presence of cellobiase. Thus, this strain could be used to obtain D-lactic acid from cellulosic materials that are pre-hydrolyzed with cellulase.
Joshi
D S
DS
NCIM Resource Center, National Chemical Laboratory, Dr. Homi Bhabha Road, Pune 411 008, Maharashtra, India.
Singhvi
M S
MS
Khire
J M
JM
Gokhale
D V
DV
D002475:Cellobiose / Q000378:metabolism; D003470:Culture Media / Q000737:chemistry / Q000378:metabolism; D019344:Lactic Acid / Q000096:biosynthesis*; D007778:Lactobacillus / Q000378:metabolism* / Q000528:radiation effects; D008965:Molasses; D016296:Mutagenesis / Q000528:radiation effects; D013395:Sucrose / Q000378:metabolism; D014466:Ultraviolet Rays
D003470:Culture Media; D002475:Cellobiose; D019344:Lactic Acid; D013395:Sucrose