The isolation and characterization of polysaccharides from longan pulp

• Published in: Separation and purification technology Vol. 63; no. 1; pp. 226 - 230
• Main Authors: Yang, Cuixian, He, Ning, Ling, Xueping, Ye, Meiling, Zhang, Chenxiao, Shao, Wenyao, Yao, Chuanyi, Wang, Zhiyuan, Li, Qingbiao
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.10.2008; Elsevier Science
• Subjects: Applied sciences; Characterization; Chemical engineering; Exact sciences and technology; Ion exchange; Isolation; Longan; Polysaccharide; Characterization; Longan; Isolation; Polysaccharide; HPLC chromatography; Microwave; Extract; Pretreatment; Ion exchange; Hot water; Gel permeation chromatography
• ISSN: 1383-5866; 1873-3794
• DOI: 10.1016/j.seppur.2008.05.004

Crude water-soluble longan polysaccharides (LPSs) were extracted from longan pulp using hot water assisted by microwave pretreatment and ethanol precipitation. Neutral and acidic polysaccharides were separated by DEAE-cellulose anion-exchange chromatography. High performance gel permeation chromatography (HPGPC) analysis showed that the average molecular weight ( M w) of neutral polysaccharide (LPS-N) was approximately 13.8 kDa, and those of two acidic polysaccharides (LPS-A1 and LPS-A2) were approximately 1382 and 571 kDa, respectively. Structural properties and compositions of these three LPS were examined by FTIR and HPLC. It was hypothesized that LPS belong to β-type acidic heteropolysaccharides with pyran group, among which LPS-N was composed of xylose and glucose at the molar ratio of 1:1.9; LPS-A1 consisted of rhamnose, xylose, arabinose and galactose at the molar ratio of 1:1.64:4.33:2.28; and LPS-A2 comprised only rhamnose. The total uronic acid content of LPS-A1 and LPS-A2 were 6% and 19%, respectively.