RT Journal Article T1 Effects of carboxymethyl modification on the acidic polysaccharides from Calocybe indica: physicochemical properties, antioxidant, antitumor and anticoagulant activities A1 Nataraj, Ambika A1 Govindan, Sudha A1 Rajendran, Archana A1 Ramani, Prasanna A1 Subbaiah, Krishnamoorthy Akkana A1 Munekata, Paulo E. S. A1 Pateiro Moure, Mirian A1 Lorenzo Rodríguez, José Manuel K1 3309.03 Antioxidantes en Los Alimentos K1 3309.20 Propiedades de Los Alimentos K1 2417.06 Micología (Setas) AB An acidic polysaccharide fraction was obtained from Calocybe indica (CIP3a) after subjecting it to hot water extraction followed by purification through DEAE-cellulose 52 and Sepaharose 6B column chromatography. The CIP3a was further modified using chloroacetic acid to yield carboxymethylated derivatives (CMCIP3a). The modified polysaccharide was characterized using various spectroscopic methods. In addition, further antioxidant, antitumor and anticoagulant activities were also investigated. The polysaccharides CIP3a and CMCIP3a were heterogeneous in nature and composed of various molar percentages of glucose, arabinose and mannose with molecular weights of 1.456 × 103 and 4.023 × 103 Da, respectively. The NMR and FT-IR data demonstrated that the carboxymethylation on the polysaccharide was successful. In comparison to CIP3a polysaccharides, the modified derivatives had lower sugar and protein contents, and higher levels of uronic acid. The in vitro antioxidant activity showed that CMCIP3a with higher molecular weight displayed an elevated ability in scavenging the DPPH radical, ABTS, superoxide, hydroxyl radical, ferric reducing power, cupric reducing power and erythrocyte hemolysis inhibition with an EC50 value of 2.49, 2.66, 4.10, 1.60, 3.48, 1.41 and 2.30 mg/mL, respectively. The MTT assay results revealed that CMCIP3a displayed a dose-dependent inhibition on five cancer cells (HT29, PC3, HeLa, Jurkat and HepG-2) in the range of 10–320 μg/mL. The APTT, PT and TT were significantly extended by CMCIP3a in relation to dosage, indicating that the anticoagulant effect of CIP was both extrinsic and intrinsic, along with a common coagulation pathway. These findings demonstrated that carboxymethylation might effectively improve the biological potential of the derivatives and offer a theoretical framework for the creation of novel natural antioxidants, low-toxicity antitumor and antithrombotic drugs. PB Antioxidants SN 20763921 YR 2022 FD 2022-12-31 LK http://hdl.handle.net/11093/4340 UL http://hdl.handle.net/11093/4340 LA eng NO Antioxidants, 12(1): 105 (2023) NO GAIN (Axencia Galega de Innovación) | Ref. IN607A2019/01 DS Investigo RD 02-nov-2024