Zizyphus Jujuba Cv Research Articles

Antioxidant activities of polysaccharides from the fruiting bodies of Zizyphus Jujuba cv. Jinsixiaozao

Four water-soluble polysaccharides fractions (ZSP1b, ZSP2, ZSP3c and ZSP4b) were isolated and purified from the fruiting bodies of Zizyphus Jujuba cv. Jinsixiaozao by DEAE-SepharoseCL-6B and SepharoseCL-6B column chromatography. Their chemical and physical characteristics were determined by chemical methods, gas chromatography (GC) and high-performance size-exclusion chromatography (HPSEC). Antioxidant activities of crude polysaccharide from the fruiting bodies of Zizyphus Jujuba cv. Jinsixiaozao (CZSP) and its purified fractions were investigated including superoxide anion, 2,2-diphenyl-1-picrylhydrazyl (DPPH), hydroxyl radical-scavenging activity and reducing power. Antioxidant results showed that ZSP3c and ZSP4b containing more uronic acid had the stronger free radical scavenging activities than ZSP1b containing no uronic acid. Available data obtained with in vitro models suggested that uronic acid was an effective indicator of antioxidant activity of the samples.

Isolation, purification and structure of a new water-soluble polysaccharide from Zizyphus jujuba cv. Jinsixiaozao

A novel water-soluble polysaccharide (ZSP3c) was isolated from Zizyphus jujuba cv. Jinsixiaozao and its structure was investigated. ZSP3c was obtained by extraction with hot water followed by purification using DEAE-SepharoseCL-6B anion-exchange, SepharoseCL-6B and Sephadex G-200 column chromatography. It was eluted as a single symmetrical narrow peak on high-performance gel-permeation chromatography (HPGPC) and the average molecular weight (Mw) was estimated to be 1.4 × 10 5 Da. The ZSP3c was composed of l-rhamnose, d-arabinose and d-galactose in a molar ratio of 1:2:8. The structural features of ZSP3c were investigated by partial hydrolysis with acid, methylation analysis and NMR spectroscopy analysis. The results revealed that the main backbone chain of ZSP3c was (1 → 4)- d-galacturonopyranosyl residues interspersed with (1 → 2)- l-rhamnopyranosyl residues and (1 → 2,4)- l-rhamnopyranosyl residues. The neutral side chains of arabinofuranosyl residues and galactopyranosyl residues were attached to the backbone at the O-4 position of rhamnopyranosyl residues.

Optimization of the ultrasonically assisted extraction of polysaccharides from Zizyphus jujuba cv. jinsixiaozao

Recently, the use of ultrasound has attracted considerable interest as an alternative approach to the traditional extraction methods. In the present study, in order to maximize the yield and purity of polysaccharides from Zizyphus jujuba cv. jinsixiaozao, response surface methodology (RSM) was employed to optimize the ultrasound-assisted extraction conditions. The results indicated optimum extraction conditions were temperature of 45–53 °C, actual sonic power of 31.7 W, time of 20 min and water/solid ratio of 20:1, respectively. The chemical analysis of crude polysaccharides revealed the polysaccharides extracted were most contaminated by co-extracted proteins. Using a short application of ultrasound, the yield of polysaccharides was 20.2% above that of classical extraction and the purity increased by a factor of 1.2, which confirmed the importance and great potential of ultrasound-assisted extraction of the polysaccharides from different tissues of plant materials.

Comparison of antioxidant capacities of extracts from five cultivars of Chinese jujube

The antioxidant capacities of extracts from five cultivars of Chinese jujube were evaluated and compared the antioxidant activities of α-tocopherol. The data indicated that the antioxidant capacity differed in cultivars. The antioxidant activities, scavenging effect on the 2,2-diphenyl-1-pycril-hydrazyl (DPPH) radical and reducing power of extracts decreased in the order of Zizyphus jujuba cv. jinsixiaozao, Zizyphus jujuba cv. yazao, Zizyphus jujuba cv. jianzao, Zizyphus jujuba cv. junzao, Zizyphus jujuba cv. sanbianhong. The antioxidant activities of extracts from Zyphus jujuba cv. jinsixiaozao, Zizyphus jujuba cv. yazao and Zizyphus jujuba cv. jianzao were stronger than α-tocopherol. Significant differences ( p < 0.05) were found between α-tocopherol and both Zyphus jujuba cv. jinsixiaozao and Zizyphus jujuba cv. yazao, while no significant differences ( p > 0.05) were found between α-tocopherol and Zizyphus jujuba cv. jianzao. Additionally, no correlation between total phenolic contents and antioxidant capacities of extracts from five cultivars of Chinese jujube was found.