Isolation, Structural Characterization, and Hypoglycemic Activities In Vitro of Polysaccharides from Pleurotus eryngii

Abstract

Pleurotus eryngii (PE) is an edible mushroom with high nutritional value. Pleurotus eryngii polysaccharides (PEPs) are one of the main active ingredients and manifest a great variety of biological activities. This study mainly focused on the chemical characterization and biological activities of PEPs, which were separated into two fractions (named WPS and P-1). WPS is mainly dominated by β-glycosidic bonds and contains α-glycosidic bonds, and P-1 only contains α-glycosidic bonds. The molecular weights of WPS and P-1 were 4.5 × 105 Da and 2.2 × 104 Da. The result of GC indicated that two the fractions were composed of rhamnose, arabinose, xylose, mannose, glucose, and galactose, with a ratio of 0.35:0.24:0.45:0.24:28.78:1.10 for WPS and 0.95:0.64:0.66:1.84:60.69:0.67 for P-1. The advanced structure studies indicated that the two fractions had no triple-helical structure, where WPS had a dense structure and P-1 had a loose structure. In addition, the antioxidant activity of WPS surpassed P-1, and the two fractions also exhibited a high hypoglycemic activity via inhibiting α-glycosidase activities and promoting the expression of PI3K-AKT signaling pathway based on in vitro assay and cell experiments.

Ultrasound-assisted polysaccharide extraction from Cercis chinensis and properites, antioxidant activity of polysaccharide

“…The protein content was determined using the Bradford method [16] . In a nutshell, both diluted polysaccharide solutions in water reacted with Coomassie brilliant blue solution, which was then measured at 595 nm.…”

Extraction and Purification, Structural Characterization and Biological Activity of a Polysaccharide, PRP‐1, from Plumeria rubra

“…Salicylic acid can react with •OH radical to form 2,3-dihydroxybenzoic acid and 2,5-dihydroxybenzoic acid. [18] The capacity of PRP-1 to scavenge OH radical was measured according to the previous literature with slight modification. [46] Briefly, 50 μL of different concentrations (0.156, 0.312, 0.625, 1.250, 2.500, 5.000 mg/mL) of PRP-1 were mixed with 50 μL of 9.0 mM FeSO 4 , 50 μL of 9.0 mM salicylic acid and 50 μL of 8.8 mM H 2 O 2 .…”

“…Because large-molecular-weight polysaccharides may have more repetitive units interacting with receptors. [18] However, another study shows that the lower the molecular weight of poly-saccharides, the higher their antioxidant capacity, presumably because low molecular weight polysaccharides present a greater number of reducing ends for reacting with free radicals species. [19] Therefore, the bioactivity of polysaccharides is not only determined by their molecular weight, but also correlate the structure, glycosidic bonds, and chemical composition.…”

Antioxidant Activity of Polysaccharides from the Edible Mushroom Pleurotus eryngii

“…Among the Pleurotus genus, Pleurotus eryngii (known as king trumpet or king oyster mushroom), besides its excellent taste and flavor, represents one of the most commercially important species in the world due to the capability to efficiently degrade many agricultural wastes and grow at a wide range of temperatures [8]. Additionally, it possesses many biological activities such as antitumor, antioxidative, immunomodulatory, hepatoprotective, anti-inflammatory, antiviral, hypoglycemic, hypolipidemic, hypocholesterolemic and fibrinolytic [3,[9][10][11][12][13][14][15]. Due to the significant content of proteins, glucans, fibers, unsaturated fatty acids, phenolic compounds, vitamins, minerals and secondary metabolites associated with a low lipid content, P. eryngii have been appreciated for their nutritional value [8,16].…”

“…Cultivated oyster mushrooms of the genus Pleurotus are interesting as a source of biologically active glucans with a variety of bioactivities, with potential use in the field of biomedical sciences [17]. In particular, many of the biological activities of P. eryngii, such as immunostimulating, antitumor, hepatoprotective, antioxidant, hypolipidemic and hypoglycemic, are attributable to polysaccharides [9,13,14,[18][19][20][21][22]. β-glucans from Pleurotus sp.…”