Structural elucidation and antioxidant activity of an arabinogalactan from the leaves of Moringa oleifera

• Published in: International journal of biological macromolecules Vol. 112; pp. 126 - 133
• Main Authors: He, Tao-Bin, Huang, Yan-Ping, Huang, YeWei, Wang, Xuan-Jun, Hu, Jiang-Miao, Sheng, Jun
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.06.2018
• Subjects: 2,2-diphenyl-1-picrylhydrazyl; agarose; Antioxidant activity; Arabinogalactan; arabinogalactans; cations; cellulose; gel chromatography; leaves; molecular weight; Moringa oleifera; Structural characterization; sugars; Arabinogalactan; Moringa oleifera; Structural characterization; Antioxidant activity
• ISSN: 0141-8130; 1879-0003; 1879-0003
• DOI: 10.1016/j.ijbiomac.2018.01.110

A novel arabinogalactan (MOP-1) was isolated from leaves of Moringa oleifera and was purified by macro-porous resin, DEAE-52 Cellulose and Sepharose 6B gel filtration chromatography. High performance gel permeation chromatography (HPGPC) analysis showed that the molecular weight of MOP-1 was 7.65 × 107 Da. Monosaccharide composition analysis indicated that sugar composition is Rha: Ara: Gal in a molar ratio of 1:7.32:12.12. Structural analysis indicated that MOP-1 has a backbone of →1)-β-d-Galp-(3,4→ with highly branched chains at O-4 position. The branches were composed of →1)-β-d-Galp-(4→, →1)-α-d-Galp-(2→, Araf-(1→, Galp-(1→. Its antioxidant activities were evaluated by DPPH radical scavenging capacity, 2,2′-Azinobis-(3-ethylbenzthiazoline-6-sulphonate) (ABTS) radical cation scavenging capacity, and ferric-reducing antioxidant power (FRAP). The results indicated MOP-1 exhibited significant antioxidant activities. •A novel arabinogalactan (designated as MOP-1) was purified from leaves of Moringa oleifera.•The structural characterizations of MOP-1 were determined.•Antioxidant activities of MOP-1 in vitro were evaluated.•MOP-1 presents a promising natural source of antioxidant agents.