摘要
【目的】探讨不同发育时期‘早酥’梨及其红皮芽变‘红早酥’梨果皮类黄酮组成与合成模式。【方法】以‘早酥’梨与芽变‘红早酥’梨不同发育时期的果实为材料,通过HPLC-MS2法测定其果实发育过程中类黄酮组分的含量变化,通过实时荧光定量PCR测定相关合成基因表达水平的变化。【结果】‘早酥’梨和‘红早酥’梨果皮类黄酮组分与含量差异较大,差异主要集中在黄酮醇、原花青素和花青苷代谢支路。2个品种果实自然发育过程中的类黄酮积累模式基本一致,以酚酸、原花青素、黄酮醇和花青苷为主的多数类黄酮组分的合成高峰位于果实发育早期,随着果实发育成熟,酚酸类物质含量呈现不断下降趋势,大部分原花青素、花青苷和黄酮醇类物质在果实膨大期后含量维持稳定。‘早酥’梨葡糖糖苷类黄酮、原花青素组分儿茶素和原花青素B2在果实成熟期出现第二个积累高峰。类黄酮合成高峰期,大多数类黄酮合成基因表达水平达到峰值。果实发育后期,下游类黄酮合成基因DFR、ANR、ANS和UFGT表达量相应提高。【结论】‘红早酥’梨果皮比‘早酥’梨果皮含有更多类黄酮物质,特别是类黄酮糖苷衍生物的种类更为丰富,含量也显著升高。‘红早酥’梨和‘早酥’梨果皮中的类黄酮合成高峰均位于果实发育早期。随着果实的发育,‘红早酥’成熟果皮中类黄酮组分含量虽有下降,但仍含有较高水平的原花青素和类黄酮糖苷类衍生物。
【Objective】‘Red zaosu’,a spontaneous sport of green Chinese white pear‘Zaosu’,overproduce anthocyanin in the fruit peel resulting in a unique appearance with red stripe.However,anthocyanin is not the only changed flavonoid compound in‘Red zaosu’pear,the flavonoid variation between the two pears is still unclear.The present study aimed at identifying flavonoid compound and their individual biosynthesis pattern in the fruit peels of‘Zaosu’pear and its red bud mutant‘Red zaosu’during their development stage.【Methods】The fruits of‘Zaosu’pear and its spontaneous sport‘Red zaosu’were selected and harvested during their development stage in Yangling,Shaanxi Province.The concentration of each flavonoid compound was qualified and quantified using HPLC-MS2.The expression level of related biosynthesis genes was detected by Real-time quantitative PCR.【Results】The composition and concentration of flavonoid compounds dispalyed various difference between‘Zaosu’pear and‘Red zaosu’pear.This diversity especially occurred in the flavonols pathway,procyanidin pathway and anthocyanin pathway.In summary,the flavonoid accumulated profiles were similar between the two cultivars,most flavo-noid compounds accumulated maximum in the early age of fruit stage including phenolic acids,procyanidins,flavonols and anthocyanins.Then the concentration of phenolic acids continuously decreased during the fruits developing,while for most procyanidins,anthocyanins and flavonols,their concentration barely changed after fruit expanding.However,the flavonoid glucosides,catechin and procyanidin B2 also accumulated in the fruit ripen stage in‘Zaosu’pear,quecertin 3-O glucoside continuously accumulated during the whole fruit development stage in‘Red zaosu’.Moreover,most flavonoid biosynthesis genes reached the highest expression levels which were consistent with the flavonoid biosynthesis peak during the young fruit age,and the downstream biosynthesis genes,such as DFR,ANR and UFGT,were up-regulated in the ripen age.【Conclusion】Flavonoid metabolites were enriched in the fruit peel of‘Red zaosu’than them in‘Zaosu’,especially for flavonoid glycosides.During the early age of fruit development,most flavonoid compounds enormously accelerated in both cultivars.The concentration of procyanidins and flavonoid glycosides stayed in a relative high level in the peel of matured‘Red zaosu’fruits,although the concentration of flavonoid compounds decreased during the fruit development stage.
作者
翟锐
房晨
范二婷
蔡猛
王志刚
徐凌飞
ZHAI Rui;FANG Chen;FAN Erting;CAI Meng;WANG Zhigang;XU Lingfei(College of Horticulture,Northwest A&F University,Yangling 712100,Shaanxi,China)
出处
《果树学报》
CAS
CSCD
北大核心
2016年第S1期75-82,共8页
Journal of Fruit Science
基金
国家自然科学基金(31572086
31171925)
关键词
梨
类黄酮
抗氧化
合成模式
Pear
Flavonoid
Antioxidant
Biosynthesis pattern
