Structural Features and Immunomodulatory Effects of Water-Extractable Polysaccharides from Macrolepiota procera (Scop.) Singer

Abstract

Macrolepiota procera (MP) is an edible mushroom used in the treatment of diabetes, hypertension and inflammation. However, the structure and biological effects of its polysaccharides (PSs) are unclear. This study investigates the structural features of a PS complex from MP (MP-PSC), its immunomodulatory activities and effects on probiotic and pathogenic bacteria. MP-PSC was obtained by boiling water, and PSs were characterized by 2D NMR spectroscopy. The immunomodulatory effects on blood and derived neutrophils, other leukocytes, and murine macrophages were studied by flow cytometry, chemiluminescence, spectrophotometry, and ELISA. The total carbohydrate content of MP-PSC was 74.2%, with glycogen occupying 36.7%, followed by β-D-glucan, α-L-fuco-2-(1,6)-D-galactan, and β-D-glucomannan. MP-PSC (200 μg/mL) increased the number of CD14+ monocyte cells in the blood, after ex vivo incubation for 24 h. It dose-dependently (50–200 μg/mL) activated the spontaneous oxidative burst of whole blood phagocytes, NO, and interleukin 6 productions in RAW264.7 cells. MP-PSC exhibited a low antioxidant activity and failed to suppress the oxidative burst and NO generation, induced by inflammatory agents. It (2.0%, w/v) stimulated probiotic co-cultures and hindered the growth and biofilm development of Escherichia coli, Streptococcus mutans and Salmonella enterica. MP PSs can be included in synbiotics to test their immunostimulating effects on compromised immune systems and gut health.

Characterization of Polysaccharide Extracts of Four Edible Mushrooms and Determination of In Vitro Antioxidant, Enzyme Inhibition and Anticancer Activities

“…Consistent with our results, it was determined that M. procera (from Bulgaria) polysaccharide extract contained high amounts of glucose (62.3%), galactose (19.7%), mannose (6.9%), and minor amounts of fucose (3.4%). 23 The main monosaccharides of Crat HW1, Crat 2%1, and Crat 25%1 polysaccharide extracts from C. tubaeformis (from Finland) were reported as glucose (11.9 ± 0.5−68.5 ± 0.5%), galactose (4.1 ± 0.2−17.8 ± 0.6%), mannose (17.8 ± 0.1−32.6 ± 0.6%), and xylose (5.7 ± 0.0−22.0 ± 0.3%). 22 The monosaccharide composition of C. cornucopioides polysaccharide fraction was mannose: xylose: glucose: fructose: arabinose with a molar ratio of 0.7:0.18:0.05:0.05:1.…”

“…The characteristic bands around 880 cm −1 showed the presence of β-glycosidic linkage of the sugar units. 22,23,28,29 2.4. 1 H NMR Analysis.…”

“…26 M. procera (from Bulgaria) polysaccharide extract was purified with a double extraction method from alcohol-insoluble parts of the mushroom, and the approximate MW was reported as 66.3 × 10 4 g/mol. 23 The approximate MW of the polysaccharide extract from M. procera (from China) obtained by the ethanol precipitation from hot water extract method was expressed as 7.71 × 10 5 Da. 38 Qu et al calculated the approximate MW of Hygrophorus lucorum polysaccharide extract (obtained by the ethanol precipitation from the hot water extract method) as 20.4 kDa.…”

“…Neutral branched (acetylated) β-D-glucomannan and α-1,4-D-glucan polysaccharides with anti-immunomodulatory and antibacterial activities were purified from M. procera. 23 Also, phenolic and triterpene compounds and antioxidant, antiproliferative, and anticholinesterase activities of different extracts of this mushroom were investigated in earlier studies. 24,25 In recent years, the remarkable bioactive properties of mushrooms have been attributed to their polysaccharide contents, and interest in the study of polysaccharides has increased.…”

Edible and Medicinal Macrofungi

“…In this Special Issue, the structural features of polysaccharides from M . procera , in addition to its immunomodulatory activities and effects on probiotic and pathogenic bacteria, are investigated [ 7 ]. Another study on polysaccharides from Volvariella volvacea (VVP) showed that it could be a good source for a moisturizing, anti-wrinkle, and whitening agent in cosmetic preparations [ 8 ].…”