Enhanced kefiran production by mixed culture of Lactobacillus kefiranofaciens and Saccharomyces cerevisiae

• Published in: Journal of biotechnology Vol. 100; no. 1; pp. 43 - 53
• Main Authors: Cheirsilp, Benjamas, Shimizu, Hiroshi, Shioya, Suteaki
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 09-01-2003; Amsterdam Elsevier; New York, NY
• Subjects: Animals; Biological and medical sciences; Biotechnology; Cell Count; Cells, Cultured; Coculture Techniques - methods; Fundamental and applied biological sciences. Psychology; Hydrogen-Ion Concentration; Kefiran; Lactic Acid - metabolism; Lactobacillus; Lactobacillus - cytology; Lactobacillus - growth & development; Lactobacillus - metabolism; Methods. Procedures. Technologies; Microbial engineering. Fermentation and microbial culture technology; Milk - metabolism; Milk - microbiology; Mixed culture; Polysaccharide production; Polysaccharides - biosynthesis; Polysaccharides, Bacterial - biosynthesis; Quality Control; Saccharomyces cerevisiae - classification; Saccharomyces cerevisiae - cytology; Saccharomyces cerevisiae - growth & development; Saccharomyces cerevisiae - metabolism; Sensitivity and Specificity; Species Specificity; Yeast; Kefiran; Yeast; Mixed culture; Polysaccharide production; Lactobacillus; Anaerobiosis; Culture medium; Aerobiosis; Fermentation; Fungi; Mixed cropping; Medium effect; Production; Bacteria; Lactobacillaceae; Ascomycetes; Lactic acid; Polysaccharide; Saccharomyces cerevisiae; Thallophyta
• ISSN: 0168-1656; 1873-4863
• DOI: 10.1016/S0168-1656(02)00228-6

In a batch mixed culture of
Lactobacillus kefiranofaciens and
Saccharomyces cerevisiae, which could assimilate lactic acid, cell growth and kefiran production rates of
L. kefiranofaciens significantly increased, compared with those in pure cultures. The kefiran production rate was 36 mg l
−1 h
−1 in the mixed culture under the anaerobic condition, which was greater than that in the pure culture (24 mg l
−1 h
−1). Under the aerobic condition, a more intensive interaction between these two strains was observed and higher kefiran production rate (44 mg l
−1 h
−1) was obtained compared with that under the anaerobic condition. Kefiran production was further enhanced by an addition of fresh medium in the fed-batch mixed culture. In the fed-batch mixed culture, a final kefiran concentration of 5.41 g l
−1 was achieved at 87 h, thereby attaining the highest productivity at 62 mg l
−1 h
−1. Simulation study considered the reduction of lactic acid in pure culture was performed to estimate the additional effect of coculture with
S. cerevisiae. Slightly higher cell growth and kefiran production rates in the mixed culture than those expected from pure culture by simulation were observed. These results suggest that coculture of
L. kefiranofaciens and
S. cerevisiae not only reduces the lactic acid concentration by consumption but also stimulates cell growth and kefiran production of
L. kefiranofaciens.