【摘要】 以雨花3号水蜜桃果实为试验材料,分步提取不同成熟度桃果实细胞壁物质(CWM)、4种果胶多糖(CDTA-1、CDTA-2、N a2CO3-1、N a2CO3-2)、3种半纤维素多糖(KOH-1、KOH-2、KOH-3)和纤维素多糖(CWM-残渣)。采用气相色谱法测定各种多糖组分中的单糖组成,探讨桃果实成熟软化过程中随果实硬度的下降,细胞壁各多糖成分含量及其单糖组成的变化。结果表明:在桃果实成熟软化过程中,富含半乳糖醛酸的果胶主链发生断裂,果胶、半纤维素、纤维素多糖中支链阿拉伯糖、半乳糖也发生不同程度的解离。细胞壁半乳糖醛酸和半乳糖的降解与桃果实软化的启动密切相关,而阿拉伯糖的降解则可能是桃果实后熟软化的重要因素。更多还原

【Abstract】 Cell wall materials（CWM） were prepared from honey peach（Yuhua 3） fruit at different maturity and extracted sequentially into four pectic polysaccharide fractions（CDTA-1,CDTA-2,Na₂CO₃-1 and Na₂CO₃-2）,three hemicellulosic fractions（KOH-1,KOH-2 and KOH-3） and cellulose rich fraction（CWM-residue）.Gas chromatography was used to determine the sugar composition of these fractions,to demonstrate the modifications of the content and sugar composition of several polysaccharides in the course of peach softening accompanied with the changes of fruit firmness.The results showed that,during peach fruit softening,the backbone of pectins rich in galacturonic acid took rupture,arabinose and galactose that lied in the side chains of pectin,hemicellulose and cellulose were also degraded.The degradation of galacturonic acid and galactose associated closely with the set-up of honey peach fruit ripening,whereas the degradation of arabinose probably contributed to later ripening and softening.更多还原