Unfolding the structure of polysaccharide isolated from Myxopyrum smilacifolium leaves toward a robust antioxidant

• Published in: Bioactive carbohydrates and dietary fibre 2023-05, Vol.29, p.100347, Article 100347
• Main Authors: Le, Trung Hieu, Nguyen, Thi Hong Chuong, Le, Lam Son, Nguyen, Dang Giang Chau, Tran, Thi Van Thi, Nguyen, Minh Nhung, Tran, Thanh Minh, Bui, Van Tuyen, Nguyen, Thi Thanh Huyen, Hoang, Thi Lan Huong, Nguyen, Chinh Chien
• Format: Article
• Language: English
• Subjects: Antioxidant activity; Extraction; Isolation; Myxopyrum smilacifolium; Polysaccharide
• ISSN: 2212-6198; 2212-6198
• DOI: 10.1016/j.bcdf.2023.100347

Polysaccharides (PS) have emerged as an outstanding candidate to tackle radical-derived health issues. To this end, the exploration of novel and robust bioactive polysaccharides has attracted increasing attention over the past decades. The presented study attempts to isolate such a polysaccharide from Myxopyrum smilacifolium leaves in an alkaline medium (i.e., Na2CO3 solution) for the first time. The structural characterizations of the obtained product were carried out by GC/MS and NMR techniques. A novel polymer (denoted as PS-MSL), possessing a molecular weight of 2.22 × 105 Da and consisting of three monosaccharides (i.e., d-glucose, d-fructose, and d-galactose) in the backbone through the repeating unit of [→3)-α-D-Galp-(1 → 2)- α-D-Glup-(1 → 3)-β-D-Frucf-2→3)]n, has been disclosed for the first time. Impressively, the achieved PS-MSL sample exhibits superior antioxidant activities toward ABTS and DPPH radical scavengers, corresponding to the IC50 values of 0.82 and 3.56 mg/mL, respectively. Such outstanding bioactivity can promote the utilization of PS-MSL polysaccharides as a promising source for antioxidant development.