Production of L(+) Lactic Acid by Lactobacillus amylophilus GV6 in Semi-Solid State Fermentation Using Wheat Bran
Basa Janakiram Naveena1, Mohammad Altaf1, Kalva Bhadrayya2 and Gopal Reddy1*
1Department of Microbiology, Osmania University, Hyderabad-500007, A.P., India
2Swaroop Technical Consultancy, Secunderabad-500003, A.P., India
Article history:
Received December 24, 2003
Accepted July 6, 2004
Key words:
L. amylophilus, wheat bran, response surface method, lactic acid, amylolytic strain, direct fermentation
Summary:
Lactobacillus amylophilus GV6 was used for direct fermentation of raw starch in wheat bran to L(+) lactic acid in semi-solid state fermentation. At m/V ratio of wheat bran 9 % (9 g of wheat bran in 100 mL of medium) with m/V ratio of CaCO3 0.375 %, 2.5 g of L(+) lactic acid was produced. To maximize the production of lactic acid, process variables like the volume of inoculum and incubation period were optimized keeping m/V ratio of wheat bran and CaCO3 at 9 and 0.375 %, respectively, and constant pH=6.5, using response surface method (RSM). The organism produced 3.5 g of L(+) lactic acid from 3.96 g of starch present in 9 g of wheat bran. Maximum starch conversion to lactic acid was observed at process conditions of wheat bran m/V ratio 9 % at 37 °C, pH=6.5, inoculum volume 3.5 mL and incubation period of 130 h.
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