Effect of soybean oil and Tween 80 on the production of botryosphaeran by Botryosphaeria rhodina MAMB-05

The addition of soybean oil and Tween 80 was evaluated with the objective of increasing the production of botryosphaeran, an exopolysaccharide (EPS) of the (1 → 3;1 → 6)-β-d-glucan type produced by the fungus Botryosphaeria rhodina MAMB-05. Factorial design and analysis by response surface methodology was developed to select the main factors that would affect and enhance EPS production. The optimized culture conditions were: 40 g l−1 glucose with 10 ml l−1 soybean oil, and 4.5 ml l−1 Tween 80, during 72 h cultivation at 28 °C (180 rpm) and initial pH 5.7. The predicted result for botryosphaeran production was 8.22 ± 1.36 g l−1, and compared with the experimental value of 7.74 ± 0.13 g l−1. Partial characterization of the botryosphaeran produced under the optimized conditions showed one type of polysaccharide with β-glycosidic linkages containing glucose as monosaccharide.