title: Influence of culture medium growth variables on Ganoderma lucidum exopolysaccharides structural features.
abstract: In this work the effect of carbon and nitrogen levels and initial pH of the wheat extract culture medium of submerged culture of Ganoderma lucidum on the amount, purity and structural features of exopolysaccharides (EPS) were studied. A low peptone level (1.65 g L(-1)) favored mycelium biomass, EPS purity, but a higher supply of peptone (4.80 g L(-1)) is needed for maximum EPS production. The carbohydrate composition of the EPS and structural features also changed significantly according to the different growing conditions, being observed significant differences in the (1 → 3)/(1 → 4)-Glcp ratio and also on the branching degree of EPS. As the biological activities of EPS are highly dependent on the polysaccharide structural features, this variability can have implications on the EPS biological activities, but can also be used advantageously to produce tailor made polysaccharides with specific applications.
authors.affiliation: CITAB - Centre for the Research and Technology of Agro-Environment and Biological Sciences, Universidade de Trás-os-Montes e Alto Douro, 5001-801 Vila Real, Portugal.
authors.forename: Irene
authors.initials: I
authors.lastname: Fraga
authors.affiliation: CQ-Vila Real, Chemistry Research Centre, Universidade de Trás-os-Montes e Alto Douro, Vila Real, Portugal.
authors.forename: João
authors.initials: J
authors.lastname: Coutinho
authors.affiliation: CITAB - Centre for the Research and Technology of Agro-Environment and Biological Sciences, Universidade de Trás-os-Montes e Alto Douro, 5001-801 Vila Real, Portugal.
authors.forename: Rui M
authors.initials: RM
authors.lastname: Bezerra
authors.affiliation: CITAB - Centre for the Research and Technology of Agro-Environment and Biological Sciences, Universidade de Trás-os-Montes e Alto Douro, 5001-801 Vila Real, Portugal.
authors.forename: Albino A
authors.initials: AA
authors.lastname: Dias
authors.affiliation: CITAB - Centre for the Research and Technology of Agro-Environment and Biological Sciences, Universidade de Trás-os-Montes e Alto Douro, 5001-801 Vila Real, Portugal.
authors.forename: Guilhermina
authors.initials: G
authors.lastname: Marques
authors.affiliation: CQ-Vila Real, Chemistry Research Centre, Universidade de Trás-os-Montes e Alto Douro, Vila Real, Portugal. Electronic address: fnunes@utad.pt.
authors.forename: Fernando M
authors.initials: FM
authors.lastname: Nunes
mesh_terms: D018533:Biomass; D018929:Cell Culture Techniques / Q000379:methods; D003470:Culture Media / Q000737:chemistry / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D011134:Polysaccharides / Q000737:chemistry* / Q000378:metabolism; D020940:Reishi / Q000737:chemistry* / Q000254:growth & development* / Q000378:metabolism
chemical_list: D003470:Culture Media; D011134:Polysaccharides
keywords: Central composite design; Exopolysaccharides; Ganoderma lucidum; Response surface methodology; Structural features; Submerged culture conditions