Chemical constituents and structural characterization of polysaccharides from four typical bamboo species leaves.

Cheng-Zhang Wang,Jian-Zhong Ye,Hong-Yu Zhang,Wen-Jun Li

doi:10.3390/molecules20034162

Abstract

In order to find bamboo leaves with high contents of bioactive polysaccharides, 32 samples were chosen to analyze their polysaccharide content by GC and sulfuric acid-anthrone colorimetric assays. Purified polysaccharides (BLPS) were separated from the four varieties P. nigra (Lodd.) Munro (PN), P. vivax McClure (PV), Chimonobambusa quadrangularis (Fenzi) Makino (CQ), and P. bambussoides cv. Tanakae (PB) by ultrasound extraction, solution precipitation, ion exchange resin, DEAE-52 and Sephadex G-100 chromatography. BLPS structural characterization was accomplished by HPLC-GPC, Fourier transform infra-red spectroscopy (FTIR) and NaIO4-HIO4 oxidation reactions. The results showed that the total polysaccharides of the bamboo leaves in samples 1–32 ranged between 1.4% and 5.4%, Samples No. 29–No. 32 (PN, PV, CQ, and PB) contained 2–3 fold more polysaccharides than No. 1~No. 28 among the 32 different species, particularly the content of galactose was in a range of 21.5%–34.1% for these four typical bamboo species leaves, which was also more than 2–3 fold higher than in No. 1–No. 28. Sugar analysis indicated that PN-PBLPS-1, PV-PBLPS-1, CQ-PBLPS-1 and PB-PBLPS-1 from the four varieties were homogeneous polysaccharides with molecular weights of 2.04 × 104, 1.15 × 104, 8.75 × 104 and 1.48 × 104 Da, respectively. PB-PBLPS-1 was a mixture of α-galactopyranose and β-d-glucopyranose linkages with α-(1→6) or β-(1→6)glycosidic bonds, while PN-PBLPS-1, PV-PBLPS-1, and CQ-PBLPS-1 had α galactopyranose linkages with α-(1→6) glycosidic bonds.

Highlights

IntroductionChina has been known as the “bamboo kingdom”, and bamboo timber is a traditional forest product containing high cellulose, hemicellulose and lignin used as a construction material [1]
Bamboo belongs to the Gramineae Bambusoideae subfamily and is one of the most valuable evergreen perennial plants in China and South-east Asia
Hemicelluoses are a family of polysaccharides which contain a backbone of D-xylopyranosyl residues, linked together by β-(1→4)-glycosidic bonds [2], while the bioactive polysaccharides in bamboo are oligosaccharides of β-D-glucan and xyloglucan or p-coumaroyl arabinoxylan [3]

Summary

Introduction

China has been known as the “bamboo kingdom”, and bamboo timber is a traditional forest product containing high cellulose, hemicellulose and lignin used as a construction material [1]. The investigation showed that bamboo shoot polysaccharides are composed of arabinoxylan (1→3,1→4)-β-D-glucan, xyloglucan and glucomannan [4], and other kinds of arabino-glucuronoxylans are isolated from bamboo shoot with a linear (1→4)-β-D-xylopranosyl backbone to which α-L-arabinofuranose units or short chains of 4-O-methylglucuronic acid. These hemicellucosic polysaccharides have a average molecular weight (Mr) range of 10 × 104–40 × 104 Da, and this results in very weak physiological activity. In order to get strongly bioactive polysaccharides with a average Mr range of less than 10 × 104 Da, scientists often use chemical or biological ways to degradate macromolecular polysaccharides

Methods

Results

Conclusion