RT Journal Article ID 3818d4963fba2ee9 A1 Cateni, Francesca A1 Zacchigna, Marina A1 Bavisotto, Celeste Caruso A1 Procida, Giuseppe A1 Bonaventura, Giuseppe A1 Saporita, Paola A1 Calvo, Roberta A1 Venturella, Giuseppe A1 Gargano, Maria Letizia T1 Structural Characterization of Polysaccharides of a Productive Strain of the Culinary-Medicinal King Oyster Mushroom, Pleurotus eryngii (Agaricomycetes), from Italy JF International Journal of Medicinal Mushrooms JO IJM YR 2018 FD 2018-08-17 VO 20 IS 8 SP 717 OP 726 K1 Pleurotus eryngii K1 polysaccharides K1 antioxidant activity K1 MTT assay K1 medicinal mushrooms AB A preliminary biological investigation of the dry basidiomata of strain C-142-c of Pleurotus eryngii has shown significant antioxidant activity. Two different polysaccharides (PEPS-A1 and PEPS-A2) were isolated from the cultivated edible mushroom, P. eryngii C-142-c strain. Based on acid hydrolysis, methylation analysis, and nuclear magnetic resonance experiments (1H, 13C, distortionless enhancement by polarization transfer, double quantum filtered correlation spectroscopy, total correlation spectroscopy, nuclear Overhauser effect spectroscopy, heteronuclear single-quantum correlation spectroscopy, and heteronuclear multiple-bond correlation spectroscopy), the structures of the repeating unit of PEPS-A1 and PEPS-A2 were established as follows: (l)PEPS-Al (α-glucan): [→6)-α-D-Glcp-(1→6)-α-D-Glcp-(l→]n; and (2) PEPS-A2 (β-glucan): [→6)-β-D-Glcp-(1→6)-β-D-Glcp-(l→]n. The antioxidant activity of PEPS-A1 and PEPS-A2 was evaluated as hydroxyl radical scavenging activity. PEPS-A1 and PEPS-A2 showed SC50 values of 400 μg/mL and 122 μg/mL, respectively, suggesting their possible use as a dietary supplement in functional foods. The polysaccharides were tested for their activity on cell viability using a colorectal adenocarcinoma cell line (HT-29). Both polysaccharides affected cell viability after 48 and 72 hours of treatment, inducing the death of 50% of HT-29 cells between 0.25 and 1 μg/mL and between 0.5 and 1 μg/mL, respectively, for PEPS-A1 and PEPS-A2. These results are promising for future applications of these mushroom-derived polysaccharides as antioxidants and antitumor agents. PB Begell House LK https://www.dl.begellhouse.com/journals/708ae68d64b17c52,66746bdc1bb430f2,3818d4963fba2ee9.html