Optimization of a bioactive exopolysaccharide production from endophytic Fusarium solani SD5.

Microbiology Laboratory, Department of Botany and Forestry, Vidyasagar University, Midnapore 721 102, West Bengal, India.
Carbohydrate Polymers (Impact Factor: 3.92). 09/2013; 97(2):627-34. DOI: 10.1016/j.carbpol.2013.05.039
Source: PubMed

ABSTRACT Endophytic fungi were less investigated for exopolysaccharide production. In this study endophytic Fusarium solani SD5 was used for optimization of exopolysaccharide production. One variable at a time method and response surface methodology were employed to explore the optimum medium compositions and fermentation conditions. The organism produced maximum exopolysaccharide after 13.68 days of incubation at 28°C in potato dextrose broth supplemented with (g%/l) glucose, 9.8; yeast extract, 0.69; KCl, 0.05; KH2PO4, 0.05 with medium pH 6.46. Use of 50ml medium in 250ml Erlenmeyer flask gives highest exopolysaccharide production. The organism produced more than two times higher exopolysaccharide (2.276±0.032g/l EPS) at optimized condition compared to pre-optimized condition (0.96±0.021). In vivo toxicity test established nontoxic nature of the EPS (≤400mg EPS/Kg of body weight). The EPS slightly altered intestinal indigenous bacteria and influenced the growth of beneficial Lactobacillus spp.

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