Strain Lactobacillus fermentum MC3 isolated from fermented bamboo shoots was used in this study. This isolate had a high exopolysaccharide (EPS) production capability. It was inoculated in the medium with a supplement of various concentrations of carbohydrate source (2, 3, 4, 5, and 6% (w/v)). The mixtures were then cultured under different conditions of initial cell density, temperatures, pH, and incubation time to identify the optimum parameters for the EPS biosynthesis of this strain. The EPS yield was measured using the phenolsulfuric acid method. The results showed that adding glucose, lactose, and sucrose to the culture medium significantly increased the EPS production with a maximum amount of 4% of sugars. The yield was the highest for glucose at 178.207 mg/L, and the obtained figures for lactose and sucrose were 148.614 mg/L and 152.272 mg/L, respectively. The results indicated that the EPS production by L. fermentum MC3 reached the maximum values at 200.728 mg/L in the medium supplemented with 4% glucose at 40 °C, pH 6.0, and initial cell density of 10 6 CFU/mL for 48 h cultivation. By methylation and gas-chromatography mass spectrometry (GC-MS), it was found that the exopolysaccharide is composed of D-mannose, D-glucose, and D-galactose at the molar ratio of 1:0.74:0.09. 10 min, 4 °C). The supernatant was precipitated with two volumes of chilled absolute ethanol.After standing overnight at 4 °C, the resultant precipitate was collected by centrifugation (12 g, 20 min, 4 °C), dissolved in distilled water, dialyzed against distilled water at 4 °C for 24 h, and lyophilized. The total of EPS (expressed as mg/L) was estimated in each sample with the phenol-

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