Schizophyllan from Schizophyllum commune BRM 060008: Potential application as an inhibitor of lipase.

ß-D-glucan has significant implications in regulating lipid metabolism and preventing diseases associated with lipid accumulation. Schizophyllan (SPG) from Schizophyllum commune fungus is a commercially important ß-glucan with applications in the health food industry, pharmacy, and cosmetics. However, SPG was obtained by submerged culture of the wood-rotting and filamentous fungus S. commune BRM 060008, which may have been isolated from the Cerrado Biome of Brazil. In this study, to confirm that the polysaccharide produced by BRM 060008 strain fermentation was indeed (1→3)(1→6)-ß-D-glucan, it was purified and characterized using Fourier transform infrared spectroscopy, thermogravimetric analysis, high-performance size exclusion chromatography, nuclear magnetic resonance, and methylation analysis. The polysaccharide produced was identified as the ß-D-glucan expected with a high molecular weight (1.093 × 106 g/mol) and the thermogravimetric analysis indicated a maximum degradation temperature of ~324 °C and a 60 % residual weight, lower than commercial SPG. The molecular structure and thermal properties of the ß-D-glucan were similar to the commercial sample. Additionally, the in vitro pancreatic lipase inhibitory activity was evaluated, investigating anti-obesity and anti-lipidemic properties. The results showed unprecedented lipase inhibition activity to SPG prepared using the S. commune strain BRM 060008, making it promising for food and pharmaceutical applications.

Comparison of cell wall polysaccharides in Schizophyllum commune after changing phenotype by mutation.

The Agaricomycetes fungi produce various compounds with pharmaceutical, medicinal, cosmetic, environmental and biotechnological properties. In addition, some polysaccharides extracted from the fungal cell wall have antitumor and immunomodulatory actions. The aim of this study was to use genetic modification to transform Schizophyllum commune and identify if the phenotype observed (different from the wild type) resulted in changes of the cell wall polysaccharides. The plasmid pUCHYG-GPDGLS, which contains the Pleurotus ostreatus glucan synthase gene, was used in S. commune transformations. Polysaccharides from cell wall of wild (ScW) and mutants were compared in this study. Polysaccharides from the biomass and culture broth were extracted with hot water. One of the mutants (ScT4) was selected for further studies and, after hydrolysis/acetylation, the GLC analysis showed galactose as the major component in polysaccharide fraction from the mutant and glucose as the major monomer in the wild type. Differences were also found in the elution profiles from HPSEC and NMR analyses. From the monosaccharide composition it was proposed that mannogalactans are components of S. commune cell wall for both, wild and mutant, but in different proportions. To our knowledge, this is the first time that mannogalactans are isolated from S. commune liquid culture.

ß-(1→3),(1→6)-Glucans: medicinal activities, characterization, biosynthesis and new horizons.

Biological activities of medicinal mushrooms have been attributed to ß-(1→3),(1→6)-glucans that are present in the cell wall of fungi and some plants. Antitumor, immunomodulatory, antimicrobial, antinociception, antiinflammatory, prebiotic, antioxidant, and antidiabetic are some of different properties already described for ß-(1→3),(1→6)-glucans. Immune activation systems, including specific ß-glucan receptors like Dectin-1, complement (CR3), and Toll (TLR), have been identified to clarify these biological effects. The ß-(1→3)-glucans are synthesized by ß-(1→3)-glucan synthase (GLS), an enzyme belonging to the glucosyltransferase group, which has a catalytic unit (FKS) and another regulatory (RHO). The mechanisms for adding ß-(1→6) branches to the non-reducing ends of the ß-(1→3)-glucan chains are unclear until now. Due to the biological importance of ß-(1→3),(1→6)-glucan, it is necessary to understand the biochemical and molecular mechanisms of its synthesis, both to optimize the production of bioactive compounds and to develop antifungal drugs that interrupt this process. Therefore, the aim of this review is to gather information about the potential of ß-(1→3),(1→6)-glucans, their methods of isolation, purification, and chemical characterization, as well as how these biomolecules are synthesized by fungi and what studies involving biotechnology or molecular biology have contributed to this subject.

Guarana powder polysaccharides: characterisation and evaluation of the antioxidant activity of a pectic fraction.

Guarana is a fruit from the Amazon whose seeds are used to produce guarana powder. Guarana powder is consumed by the population mainly for its stimulant activity. It has been shown that guarana seeds contain low-molar-mass compounds; however, no data have been reported concerning the polysaccharides. In this work, the polysaccharides present in guarana powder were investigated. A pectic fraction and a xylan were isolated and characterised. Antioxidant activity tests were performed with a methanolic extract and the pectic fraction at concentrations of 0.1-10 mg/ml. The methanolic extract exhibited a strong capacity for scavenging DPPH radicals (90.9% at 10 mg/ml). At the same concentration, the polysaccharide showed a DPPH(·)-scavenging activity of 68.4%. At a higher concentration, the methanolic extract and the polysaccharide exhibited similar hydroxyl radical-scavenging effects (~70%). The results suggest that the polysaccharides present in guarana can contribute to the possible biological effects of guarana powder.

Characterization and antineoplasic effect of extracts obtained from Pleurotus sajor-caju fruiting bodies.

Fungi of the Pleurotus genus present a great industrial interest due to their possibility of producing pharmacological compounds, pigments, aromas, organic acids, polysaccharides, enzymes, vitamins, amino acids, etc. Among the therapeutic products, we can highlight those with antineoplasic activity, attributed to the fungi cell wall components. Based on this, the objective of this work was to study the antineoplasic capacity of the polysaccharidic fractions obtained from Pleurotus sajor-caju fruiting bodies. Female Swiss mice were inoculated with the Ehrlich ascitic tumor (5 x 10(6) cells/animal) in ascitic form. The polysaccharidic fractions were administered intraperitoneally, during a 6-day period. Fractions FI and FII presented a lower volume of ascitic liquid (3.1 and 1.8 mL, respectively) and a higher reduction in the number of neoplasic cells present in the ascitic liquid (86.2% and 85%, respectively), when compared to the positive control (group inoculated with the tumor but without treatment). These fractions were characterized in terms of monosaccharide composition. Glucose was the major component detected, followed by galactose and mannose. The anomeric carbon configuration of the beta-glucan was confirmed by the (13)C NMR (delta 103.7). Substituted and free C3 and C6 were also detected. Protein bands were confirmed through infrared analysis.