Botryosphaeran

Botryosphaeran is an exopolysaccharide (EPS) produced by the ascomyceteous fungus Botryosphaeria rhodina. Characterization of the chemical structure of botryosphaeran showed this EPS to be a (1→3)(1→6)-β-D-glucan.This particular β-glucan can be produced by several strains of Botryosphaeria rhodina that include: MAMB-05, DABAC-P82, and RCYU 30101. Botryosphaeran exhibits interesting rheological properties and novel biological functions including hypoglycaemia, hypocholesterolaemia, anti-atheroslerosis and anti-cancer activity, with potential commercial applications. Three cosmetic products formulated with botryosphaeran have been developed to promote skin health and treat skin conditions for future intended commercialization purposes. Botryosphaeran is an exopolysaccharide (EPS) produced by the ascomyceteous fungus Botryosphaeria rhodina. Characterization of the chemical structure of botryosphaeran showed this EPS to be a (1→3)(1→6)-β-D-glucan.This particular β-glucan can be produced by several strains of Botryosphaeria rhodina that include: MAMB-05, DABAC-P82, and RCYU 30101. Botryosphaeran exhibits interesting rheological properties and novel biological functions including hypoglycaemia, hypocholesterolaemia, anti-atheroslerosis and anti-cancer activity, with potential commercial applications. Three cosmetic products formulated with botryosphaeran have been developed to promote skin health and treat skin conditions for future intended commercialization purposes. The ascomycete and filamentous fungus, Botryosphaeria rhodina (strain MAMB-05), was isolated from a canker on the trunk of a eucalypt tree, and was molecularly characterized by sequencing the Internal Transcribed Spacer (ITS) region of rDNA. The β-glucan, botryosphaeran, was discovered accidentally in 1994 while cultivating Botryosphaeria rhodina MAMB-05 on nutrient media containing glucose to produce the enzyme, laccase. This fungal isolate produces a constitutive laccase that could be induced to higher enzyme titers by various lignin-like aromatic compounds, and especially veratryl alcohol. The fungus was found to be ligninolytic. Botryosphaeran is secreted by the fungus during growth and appears in the fermentation broth where its presence causes an increase in the broth’s viscosity. It can easily be extracted from the broth by precipitation methods. Veratryl alcohol, however, suppresses the formation of botryosphaeran. Botryosphaeran is produced under submerged fermentation conditions when Botryosphaeria rhodina MAMB-05 is grown on nutrient media containing glucose and mineral salts. Extracting the fermentation broth with alcohol causes the EPS (botryosphaeran) to precipitate from solution, and this can be separated by centrifugation or filtration. The precipitate recovered can be lyophilized to a white fibrous material that is sparingly soluble in water. Alternatively, the recovered precipitate is resolubilized in water (gentle heating with stirring) to form a viscous solution that forms a firm gel when cooled to 5°C. Solubilization of botryosphaeran can be enhanced through chemical derivatization with various functional groups. The influence of the composition of the nutrient medium, including nitrogen, phosphate, minerals, supplements (soybean oil, Tween 80), and the carbon source (carbohydrates),, is important in enhancing the production of botryosphaeran and biomass during fermentation by Botryosphaeria rhodina MAMB-05. Catabolite repression, and the presence of β-glucan-hydrolyzing enzymes that attack botryosphaeran during the fermentation process are critical and limit the production of botryosphaeran. Statistical factorial design methods, such as the response surface methodology (RSM), are effective in investigating complex fermentation parameters and their interactions to optimize metabolite production by microorganisms. RSM assists in defining the effects and interactions of the physiological factors playing a role in biotechnological processes in the production of microbial metabolites including exopolysaccharides such as β-glucans. Statistical methodologies reduce the number of experiments to provide sufficient information for statistically acceptable results.