TITLE:
Optimization of Nutrients in Fermentative Lactic Acid Production Using Oil Palm Trunk Juice as Substrate
AUTHORS:
Nisa Saelee, Klanarong Sriroth
KEYWORDS:
Lactic Acid, Oil Palm, Oil Palm Trunk Juice, OPT, Lactobacillus rhamnosus, Box Behkhen Design, BBD
JOURNAL NAME:
Advances in Bioscience and Biotechnology,
Vol.5 No.12,
October
31,
2014
ABSTRACT: Complex nutrients e.g. carbon, nitrogen, peptides, vitamin and salts
significantly play important roles in lactic acid production efficiency
depending on types of microorganism and sources of raw material. In this study
oil palm trunk juice and Lactobacillus rhamnosus TISTR 108 (ATTC 10863)
were utilized for lactic acid production. Additional nutrients including
peptone, yeast extract and mixed salts were tested. Response surface
methodology involving Box Behkhen Design (BBD) was applied to examine the
optimal condition. Prediction of optimization was performed using full
quadratic regression equation. The predicted maximum lactic acid concentration
was obtained at 64.05 g·l-1 within a period of 48 h under an optimal
condition of 10 g·l-1 peptone with mixed salts containing 0.4 g·l-1 MgSO4·7H2O, 0.1 g·l-1 MnSO4·4H2O,
3 g·l-1 K2HPO4, 3 g·l-1 KH2PO4 and 3 g·l-1 CH3COONa·3H2O in 250 ml shake
flask using CaCO3 as a titrant. Verification of optimization condition
was performed in 2 l fermenter using Ca(OH)2 as neutralizing agent.
Increase in lactic acid fermentation was achieved at 92.81 g·l-1 at 48
h cultivation. The lactic acid yield and volumetric productivity were 0.94 g·g-1 and 1.91 g l-1·h-1, respectively. This suggests that OPT
juice is potentially used as carbon and nutrient sources for lactic acid
production.