title: Correlation between the production of exopolysaccharides and oxalic acid secretion by Ganoderma applanatum and Tyromyces palustris.
abstract: The secretion of exopolysaccharides and oxalic acid in cultures of a white rot Ganoderma applanatum strain and a brown rot Tyromyces palustris strain were tested in terms of culture time, pH range, and temperature. The high yield of exopolysaccharides (EPS) required a moderate temperature of 28 °C for G. applanatum and 20 °C for T. palustris. G. applanatum and T. palustris accumulated more EPS when the concentration of the carbon source (maltose for G. applanatum and fructose for T. palustris) was 30 g/L. The results indicate that the production of oxalic acid by G. applanatum is correlated with the initial pH value of the culture medium and the concentration of oxalic acid increased to 1.66 ± 0.2 mM at the initial pH of 6.5 during the fungal growth. During the growth of T. palustris, the reduction of the initial pH value of the growing medium lowered the oxalic acid concentration from 7.7 ± 0.6 mM at pH 6.0 to 1.99 ± 0.2 mM at pH 3.5. T. palustris accumulated considerably more oxalic acid than G. applanatum and its presence did not affect significantly the production of exopolysaccharides. We also observed that the maximum amounts of exopolysaccharides secreted during cultivation of G. applanatum and T. palustris were 45.8 ± 1.2 and 19.1 ± 1.2 g/L, respectively.
authors.affiliation: Department of Biochemistry, Maria Curie-Sklodowska University, Akademicka Street 19, 20-033, Lublin, Poland, moniosi73@gmail.com.
authors.forename: Monika
authors.initials: M
authors.lastname: Osińska-Jaroszuk
authors.forename: Kamila
authors.initials: K
authors.lastname: Wlizło
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Szałapata
authors.forename: Anna
authors.initials: A
authors.lastname: Jarosz-Wilkołazka
mesh_terms: D002244:Carbon / Q000378:metabolism; D055453:Coriolaceae / Q000254:growth & development* / Q000378:metabolism*; D003470:Culture Media / Q000737:chemistry; D032902:Ganoderma / Q000254:growth & development* / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D019815:Oxalic Acid / Q000378:metabolism*; D011134:Polysaccharides / Q000378:metabolism*; D013696:Temperature; D013997:Time Factors
chemical_list: D003470:Culture Media; D011134:Polysaccharides; D002244:Carbon; D019815:Oxalic Acid