Utilization of sugar molasses for economical l(+)-lactic acid production by batch fermentation of Enterococcus faecalis

Department of Material Chemical and Biochemical Engineering, Chonnam National University, Gwangju 500-757, Korea; Biohelix Co., Biotechnology Industialization Center, Naju, Jeonnam 520-811, Korea; School of Biological Sciences and Technology, Chonnam National University, Gwangju 500-757, Korea
Enzyme and Microbial Technology (Impact Factor: 2.97). 12/2004; DOI: 10.1016/j.enzmictec.2004.08.008

ABSTRACT Lactic acid production from sugar molasses by batch fermentation of Enterococcus faecalis RKY1 was investigated in order to reduce the manufacturing cost of lactic acid. When the fermentation was carried out at pH 7.0, 95.7 g/l of lactic acid was obtained with a yield of 94.9% and productivity of 4.0 g/l h. Lactic acid fermentation using molasses was significantly affected by yeast extract concentrations. The maximum lactic acid productivity was obtained to 5.3 g/l h at 20 g/l of yeast extract. The final lactic acid increased with the increase of molasses concentrations, whereas the lactic acid productivity decreased probably due to substrate inhibition. When the medium containing 15 g/l of yeast extract was used, the maximum lactic acid concentration (134.9 g/l) and the maximum productivity (4.3 g/l h) were obtained at molasses concentrations of 333 g/l (equivalent to 170 g/l of total sugar) and 130 g/l (equivalent to 68 g/l of total sugar), respectively. In addition, l(+)-lactic acid content of lactic acid produced from molasses was above 98% in all cases experimented in this study.

  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The present study was conducted to investigate the influence of initial sucrose concentration, pH and aeration rate on biomass and inulinase production by Kluyveromyces marxianus var. bulgaricus in a stirred batch reactor. Maximum inulinase activity (15.29 UmL-1) was obtained at a sucrose concentration of 10 g L-1, pH 5.0 and aeration rate of 1 vvm. The 20 g L-1 sucrose concentration was suitable for cell growth; however, enzymatic activity at this concentration was inhibited due to catabolic repression. The increase in aeration rate caused a reduction in enzyme activity with no relevant biomass increase.
    Brazilian Archives of Biology and Technology 06/2010; 53(3):701-707. · 0.45 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The aim of this work was to study the capability of amylolytic of lactic acid bacteria to hydrolyze the onggok tapioca for lactic acid production. Of the three strains tested, Streptococcus bovis was selected. S. bovis was found to produce lactic acid directly from onggok substrate at pH 5.5. It has been demonstrated that lactic acid concentration as high as 39.98 g/l can be obtained from onggok-tofu liquid waste-20 g/l concentrates maguro waste. The yield and productivity of lactic acid in batch fermentation were 85% and 3.01 g/l.h, respectively.
  • [Show abstract] [Hide abstract]
    ABSTRACT: Para la producción fermentativa de ácido láctico se evaluaron como sustrato residuos de cosecha de caña de azúcar (variedad CC85-92). Las fermentaciones se realizaron a 32°C y pH 6,0, utilizando jugos obtenidos de hojas y cogollos (JTL), y Lactococcus lactis subs. lactis aislado de caña de azúcar de la misma variedad. En las fermentaciones se midieron la concentración de ácido láctico (LA), la conversión de sustrato (SC), la concentración de biomasa, la velocidad de formación de producto (rp) y el rendimiento (Yp/s), y los resultaron se compararon con fermentaciones que utilizaron la misma cepa y medio de cultivo comercial MRS adicionado de glucosa hasta 60g·l-1. Utilizando JTL se pueden obtener concentraciones de ácido láctico por encima de 28,5g·l-1 y rendimientos de 0,85g·g-1 en 48 horas de fermentación. Los sustratos JTL y MRS mostraron diferencias estadísticamente significativas en Yp/s, SC y concentración de biomasa, y diferencias estadísticamente no significativas en LA y rp. Los resultados sugieren que los residuos de cosecha de caña de azúcar pueden ser utilizados como materia prima barata para la producción fermentativa de ácido láctico.
    Interciencia 05/2007; 32(5):328-332. · 0.25 Impact Factor