Enzyme-extracted raspberry pectin exhibits a high-branched structure and enhanced anti-inflammatory properties than hot acid-extracted pectin. (30th July 2022)

• Record Type: Journal Article
• Authors: Wu, Dongmei; Chen, Shiguo; Ye, Xingqian; Zheng, Xiaoliang; Ahmadi, Shokouh; Hu, Weiwei; Yu, Chengxiao; Cheng, Huan; Linhardt, Robert J.; Chen, Jianle
• Is Part Of: Food chemistry. Volume 383(2022)
• Publication Date: 2022-07-30
• Subjects: Raspberry -- Polysaccharide -- Arabinan sidechains -- Purification -- Characterization -- Immunomodulatory; Food -- Analysis -- Periodicals; Food -- Composition -- Periodicals; 664
• DOI: 10.1016/j.foodchem.2022.132387
• Languages: English
• ISSNs: 0308-8146

Abstract

Highlights: Two purified raspberry pectins were extracted using different methods. Enzyme extraction kept the highly branched structure of raspberry pectin. Enzyme-extracted pectin exhibited higher anti-inflammatory activity. Abstract: To characterize the structure of purified raspberry pectin and discuss the impact of different extraction methods on the pectin structure, raspberry pectin was extracted by hot-acid and enzyme method and purified by stepwise ethanol precipitation and ion-exchange chromatography isolation. Enzyme-extracted raspberry pectin (RPE50%-3) presented relatively intact structure with molecular weight of 5 × 10 4 g/mol and the degree of methylation was 39%. The 1D/2D NMR analysis demonstrated RPE50%-3 was a high-branched pectin mainly containing 50% homogalacturonan, 16% branched α-1, 5-arabinan and α-1, 3-arabinan, 18% β-1, 4-galactan and β-1, 6-galactan. Acid-extracted raspberry pectin (RPA50%-3) contained less arabinan than RPE50%-3. Moreover, RPE50%-3 inhibited the nitric oxide (NO), TNF-α, IL-6 production of lipopolysaccharide-induced macrophages by 67%, 22% and 46% at the dosage of 200 ug/mL, while the inhibitory rate of RPA50%-3 were 33%, 9%, and 1%, respectively. These results suggested that enzyme-extracted raspberry pectin contained more arabinan sidechains and exhibited better immunomodulatory effect.