Polysaccharides from Basidiocarps of Cultivating Mushroom Pleurotus ostreatus: Isolation and Structural Characterization

Abstract

Oyster mushrooms are an interesting source of biologically active glucans and other polysaccharides. This work is devoted to the isolation and structural characterization of polysaccharides from basidiocarps of the cultivated oyster mushroom, Pleurotus ostreatus. Five polysaccharidic fractions were obtained by subsequent extraction with cold water, hot water and two subsequent extractions with 1 m sodium hydroxide. Branched partially methoxylated mannogalactan and slightly branched (1→6)-β-d-glucan predominated in cold- and hot-water-soluble fractions, respectively. Alternatively, these polysaccharides were obtained by only hot water extraction and subsequent two-stage chromatographic separation. The alkali-soluble parts originating from the first alkali extraction were then fractionated by dissolution in dimethyl sulfoxide (DMSO). The polysaccharide insoluble in DMSO was identified as linear (1→3)-α-d-glucan, while branched (1→3)(1→6)-β-d-glucans were found to be soluble in DMSO. The second alkaline extract contained the mentioned branched β-d-glucan together with some proteins. Finally, the alkali insoluble part was a cell wall complex of chitin and β-d-glucans.

Extraction and characterization of chitin and chitosan from Termitomyces titanicus

“…Several recent studies [11,15,19,26,37] show that chitin and chitosan can be extracted from different species of fungus, including Ganoderma lucidum, Agaricus sp., Pleurotus sp., Pleurotus ostreatus, Fomes fomentarius, Boletus bovinus, etc. The extraction yield of the obtained chitin varied between 7 and 43% depending on the type of fungus.…”

Extraction and Physicochemical Characterization of Chitin Derived from the Asian Hornet, Vespa velutina Lepeletier 1836 (Hym.: Vespidae)

“…Structurally, it is the simplest of the glycosaminoglycans, being a β (1→4) linked linear homopolymer of N-acetylglucosamine (GlcNAc, [C 8 H 13 O 5 N] n, where n››1). It primarily exists in alga [1,2], fungi [3], arthropods (crab, shrimp, crayfish, and insects) [4], copepod, and mollusks (squid) [5]. It was cited that approximately 100 billion tons of CHI are produced, as a major structural component in the exoesqueleton from the above organisms [6], being around 80,000 t obtained per year from the marine by-products by industry for commercial exploitation.…”

“…Two new sources as fungi and insect species have been recently researched as an alternative origin for these functional materials in order to expand the chitin-chitosan based source and obtain a better material and more consistent quality [3,7,[27][28][29][30][31]. The insect and fungal biopolymers have many features that can make them more advantageous than those biopolymers from seafood waste origin [32], due to potential advantages in terms of homogenous polymer length, high degree of deacetylation and solubility over the current marine source [7].…”

Immunomodulatory and antioxidant effects of polysaccharides from the parasitic fungus Cordyceps kyushuensis

“…Purification and structural characterization of fungal polysaccharides is thus very important for their further application as selective and effective immune modulators (Baeva et al 2019). The present study was undertaken to elucidate the antioxidant and immune stimulatory activities of the polysaccharides from the stoma of C. kyushuensis.…”