Determination of exopolysaccharides production by lactic acid bacteria of water kefir grains

Abstract

This work presents the investigation of exopolysaccharides (EPS) production by lactic acid bacteria from water kefir grains. Preliminary characterization, based on some morphological and physiological characteristics showed that the selected strains, T1 and T5 belonging to the genera Leuconostoc and Lactobacillus, respectively. Cultures were grown in modified MRS broth with sucrose instead of glucose. According to the investigation of influence of incubation time and temperature as well as concentration of sucrose on the amount of EPS produced, it was determined that the highest yields of 4.88 g / l and 8.20 g / l (for strain T1 and strain T5, respectively) were obtained in medium containing 10% sucrose, at 30oC, after 48 h of incubation.

U radu je odredjivana sposobnost proizvodnje egzopolisaharida (EPS) kod bakterija mlečne kiseline izolovanih iz vodenog kefira. Preliminarna karakterizacija, na osnovu odabranih morfoloških i fizioloških karakteristika, je pokazala da odabrani sojevi T1 i T5, pripadaju rodovima Leuconostoc i Lactobacillus, respektivno. Kulture su gajene u modifikovanom MRS bujonu sa saharozom umesto glukoze. Ispitivanjem uticaja vremena i temperature inkubacije kao i koncentracije saharoze, na količinu proizvedenih egzopolisaharida, utvrdjeno je da je najveći prinos, od 4.88 g/l i 8.20 g/l (za soj T1 i soj T5, respektivno) ostvaren u podlozi sa 10% saharoze, na 30oC, nakon 48h inkubacije.