Production of kefiran from molasses and spent yeast cells by lactobacillus kefiranofaciens JCM 6985

Abstract

Kefiran is an exopolysaccharides produced by Lactobacillus kefiranofaciens isolated from kefir grains. Kefir grains is a starter of traditional fermented milk that originated in the Caucasian Mountains in Russia. Kefiran contains glucose and galactose at a ratio 1:1. It is widely used as thickeners, stabilizers, emulsifiers and gelling agents. It also has antimicrobial and antitumor activity. The main aim of this work was to produce kefiran from low-cost carbon and nitrogen sources. Firstly, the effect of various sugars including glucose, sucrose, lactose, galactose and lactose on kefiran production were investigated. It was found that lactose gave the highest kefiran production of 283.33±15.3 mg/L followed by glucose (210±20 mg/L) and sucrose (180±5.8 mg/L). When molasses was used as a carbon source, the optimal molasses concentration was 80 g/L which gave kefiran production of 235±5.7 mg/L. The kefiran production using various low-cost nitrogen sources were investigated. Among nitrogen sources tested, spent yeast cells gave the highest kefiran production of 580±10 mg/L. Moreover, when spent yeast cells was hydrolyzed and used as nitrogen source the kefiran production was increased up to 1,286±18 mg/L. These results show that molasses and spent yeast cells can be used as low-cost nutrients for kefiran production. Kefiran is an exopolysaccharides produced by Lactobacillus kefiranofaciens isolated from kefir grains. Kefir grains is a starter of traditional fermented milk that originated in the Caucasian Mountains in Russia. Kefiran contains glucose and galactose at a ratio 1:1. It is widely used as thickeners, stabilizers, emulsifiers and gelling agents. It also has antimicrobial and antitumor activity. The main aim of this work was to produce kefiran from low-cost carbon and nitrogen sources. Firstly, the effect of various sugars including glucose, sucrose, lactose, galactose and lactose on kefiran production were investigated. It was found that lactose gave the highest kefiran production of 283.33±15.3 mg/L followed by glucose (210±20 mg/L) and sucrose (180±5.8 mg/L). When molasses was used as a carbon source, the optimal molasses concentration was 80 g/L which gave kefiran production of 235±5.7 mg/L. The kefiran production using various low-cost nitrogen sources were investigated. Among nitrogen sources tested, spent yeast cells gave the highest kefiran production of 580±10 mg/L. Moreover, when spent yeast cells was hydrolyzed and used as nitrogen source the kefiran production was increased up to 1,286±18 mg/L. These results show that molasses and spent yeast cells can be used as low-cost nutrients for kefiran production. Normal 0 false false false EN-US X-NONE TH /* Style Definitions */ table.MsoNormalTable {mso-style-name:ตารางปกต; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin-top:0cm; mso-para-margin-right:0cm; mso-para-margin-bottom:8.0pt; mso-para-margin-left:0cm; line-height:107%; mso-pagination:widow-orphan; font-size:11.0pt; mso-bidi-font-size:14.0pt; font-family:Calibri,sans-serif; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin;}