海拔对桃儿七果实特性、活性成分含量及抗氧化能力的影响

Effect of altitude on fruit characteristics,bioactive compounds and antioxidant capacity in Podophyllum hexandrum

为了探明海拔对桃儿七果实特性以及活性成分积累的影响,更好地保护和利用桃儿七野生资源,本研究以不同海拔(2400~2500 m和2900~3000 m)的野生桃儿七果实为材料,分别对果实特性、活性物质含量以及抗氧化能力进行了测定与分析。结果表明,海拔对桃儿七果实特性、活性成分积累以及组织间的差异性具有显著影响。低海拔果实开花期至成熟期的天数为111 d,较高海拔延长5 d,成熟期较高海拔提前13 d,低海拔果实的纵径、横径、干重、种子数量和千粒干重均高于高海拔,而纵横比则相反;低海拔果皮和果肉中可溶性糖、总黄酮和酚类化合物的含量分别显著高于高海拔;低海拔果皮70%和10%乙醇提取液的抑制率、铁离子还原/氧化能力(FRAP值)以及果肉70%乙醇提取液的FRAP值分别显著大于高海拔。同一海拔不同组织而言,果肉中可溶性糖的含量显著高于果皮,总黄酮和酚类含量则相反;在低海拔地区,果皮70%和10%乙醇提取液的抑制率和FRAP值分别显著大于果肉,而在高海拔地区,仅果皮70%乙醇提取液的FRAP值显著大于果肉。因此,较低海拔有利于桃儿七果实的生长与发育以及果实中可溶性糖、总黄酮和酚类化合物等活性物质的积累。

This study investigated the effect of altitude on fruit characteristics and the accumulation of bioactive compounds in the fruit of Podophyllum hexandrum,with the aim of better protecting and utilizing this wild resource.The experiments were conducted at different altitudes（2400-2500 m and 2900-3000 m）,with measurements taken of fruit characteristics,bioactive compound content and antioxidant capacity.Differences in altitude showed very strong effects on fruit characteristics and the accumulation of bioactive compounds in fruit tissue.The duration from flowering to fruit ripening stages at lower altitudes was 111 d,5 d longer than that at higher altitudes,and the duration of the ripening stage increased by 13 d.The length,diameter,dry weight,seed number and thousand-seed weight per fruit were greater at lower than at higher altitudes,while the ratio of length-diameter was lower.The contents of soluble sugar,total flavonoid and phenolic in both peel and pulp at lower altitudes were significantly higher than those at higher altitudes.The inhibition percentages（I%） and ferric reducing/antioxidant power（FRAP value） of 70% and 10% ethanol extracts from the peel and the FRAP value of 70% ethanol extracts from the pulp at lower altitudes were significantly higher than those at higher altitudes.At the same altitude,the content of soluble sugar in the pulp was significantly greater than that in the peel,while the contents of total flavonoid and phenolic were lower.The I% and FRAP value of 70% and 10% ethanol extracts from peel were significantly greater than those from pulp at lower altitudes,while at higher altitudes only the FRAP value of 70% ethanol extracts from the peel was significantly greater than that from the pulp.In conclusion,this study indicates that low altitude is conducive for fruit growth and development and for the accumulation of soluble sugar,total flavonoid and phenolic contents in the fruit of P.hexandrum.