以'华秀'李(Prunus salicina 'Huaxiu')果实为实验材料,对不同果肉着色期(黄色期、橙色期和红色期)的果实品质指标〔果实硬度、可溶性固形物(SS)含量、可滴定酸(TA)含量和固酸比(SS/TA)〕、色素〔叶绿素(Chl)、类胡萝卜素(Car)和花青苷(Ant)〕含量、抗氧化指标(类黄酮含量、总酚含量和DPPH·清除力)和内源激素〔吲哚乙酸(IAA)、玉米素(ZT)、脱落酸(ABA)和赤霉素(GA3)〕含量进行了比较,并对这些指标进行了相关性分析.结果表明:随着果肉着色进程,果实硬度及TA和Chl含量不断下降,SS/TA、DPPH·清除力及Car、Ant、类黄酮和IAA含量不断上升,但SS和ZT含量先上升后下降,而总酚、ABA和GA3含量先下降后上升.其中,果实硬度和SS含量在果肉由黄色期向橙色期转变过程中变化显著(P<0.05),Car及上述色素和内源激素含量在果肉由橙色期向红色期转变过程中变化显著,而TA、Chl和Ant含量及SS/TA在不同着色期差异显著.并且,随着果肉着色进程,Chl和Car含量所占比例不断下降,而Ant含量所占比例不断上升,且Chl和Ant含量所占比例变化明显.相关性分析结果表明:Car含量与类黄酮、总酚和IAA含量呈显著正相关;Ant含量与类黄酮和IAA含量呈显著正相关,与DPPH·清除力呈极显著(P<0.01)正相关;类黄酮含量与DPPH·清除力呈显著正相关,与IAA含量呈极显著正相关;DPPH·清除力与IAA含量呈显著正相关;ZT含量与ABA含量呈显著负相关.研究结果显示:在果肉着色过程中,'华秀'李果实硬度下降,酸味减少,甜味增加,色泽变艳,抗氧化能力增强;其果肉颜色是叶绿素、类胡萝卜素和花青苷综合作用的结果,且其果肉颜色与其抗氧化能力关系密切,因此,可通过果肉颜色判断'华秀'李果实的抗氧化能力.%Taking Prunus salicina 'Huaxiu' fruit as experimental material, fruit quality indexes 〔fruit firmness,soluble solid(SS)content,titratable acid(TA)content,and soluble solid/titratable acid ratio (SS/TA)〕, pigment 〔chlorophyll(Chl), carotenoid(Car)and anthocyanin(Ant)〕 contents, antioxidant indexes(flavonoid content, total phenols content, and DPPH·scavenging ability)and endogenous hormone 〔indole acetic acid(IAA), zeatin(ZT), abscisic acid(ABA), and gibberellin (GA3)〕 contents were compared at different flesh coloring stages(yellow stage, orange stage, and red stage),and correlation analysis among these indexes was analyzed. The results show that with the process of flesh coloring, fruit firmness, and TA and Chl contents decrease gradually, SS/TA, DPPH· scavenging ability,and Car,Ant,flavonoid and IAA contents increase gradually,but SS and ZT contents increase firstly and then decrease,while total phenols, ABA and GA3contents decrease firstly and then increase. In which, changes of fruit firmness and SS content are significant(P<0.05)during flesh transforming period from yellow stage to orange stage, and those of Car, above pigment and endogenous hormone contents are significant during flesh transforming period from orange stage to red stage,while the differences in TA,Chl and Ant contents and SS/TA at different coloring stages are significant. Besides, with the process of flesh coloring,the proportions of Chl and Car contents decrease gradually,while that of Ant content increases gradually,and those of Chl and Ant contents change obviously. The correlation analysis results show that there are significantly positive correlations of Car content with flavonoid, total phenolic and IAA contents, significantly positive correlations of Ant content with flavonoid and IAA contents and an extremely significantly(P<0.01)positive correlation with DPPH·scavenging ability,a significantly positive correlation of flavonoid content with DPPH·scavenging ability and an extremely significantly positive correlation with IAA content, a significantly positive correlation of DPPH· scavenging ability with IAA content, and a significantly negative correlation of ZT content with ABA content. It is suggested that during flesh coloring process, fruit firmness of P. salicina 'Huaxiu' decreases, sour taste reduces, sweet taste increases, color is brightening, and antioxidant ability enhances; its flesh color is the result of comprehensive effect of chlorophyll, carotenoid, and anthocyanin,and its flesh color is closely related to its antioxidant ability. Therefore, the antioxidant ability of P. salicina 'Huaxiu' fruit can be judged by flesh color.
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