The Relative Molecular Mass, Monosaccharide Composition and Antioxidant Activity of Ziziphus jujuba FleshPolysaccharide at Different Stages

For the purpose of exploring the polysaccharide content, relative molecular mass, monosaccharide composition, as well as antioxidant activity in Ziziphus jujuba flesh polysaccharide (ZJFP) at distinct growth stages. The content, relative molecular weight, monosaccharide composition and free radical scavenging ability of ZJFP in wild-type and plant-type at different growth stages were studied by phenol-sulfuric acid assay, high performance gel chromatography, high performance ion chromatography, and DPPH free radical scavenging experiment. Moreover, the results determined that the polysaccharide content of ZJFP in both wild and plant types demonstrated a trend of first decreasing and consequently rising. Furthermore, the relative molecular mass of the two types of ZJFP gradually decreased with the development of the Ziziphus jujuba. During the initial stage of fruit development, the ZJFP exhibited the highest content of rhamnose, reaching 46.14 mg/g, followed by galactose up to 33.10 mg/g. Whereas, in the later stage of fruit development, the highest monosaccharide content in the two types of ZJFP was arabinose up to 60.30 mg/g, preceded by galacturonic acid up to 45.02 mg/g. Additionally, the trend of DPPH free radical scavenging capacity of ZJFP of the two types was identical to the trend of polysaccharide content in Ziziphus jujuba flesh. Plant-type and wild-type Ziziphus jujuba illustrated the identical trend regarding polysaccharide content, the relative molecular weight of polysaccharides, monosaccharide composition, as well as free radical scavenging ability, and both were of the type of fruit that reduces sugar accumulation. The research serve as a valuable reference for the future development and utilization of Ziziphus jujuba flesh resources.