不同经霜时间霜桑叶品质的变化规律  

Change in Quality of Frosted Mulberry Leaves After Different Frost⁃ing Time

作　　者：王丽[1,2] 文海朝 张凌峰 杨凝薇 李红姣 Wang Li;Wen Haichao;Zhang Lingfeng;Yang Ningwei;Li Hongjiao(College of Forestry,Hebei Agricultural University,Baoding Hebei 071000,China;Key Laboratory of Forest Germ-plasm Resources and Forest Protection of Hebei Province,Baoding Hebei 071000,China)

机构地区：[1]河北农业大学林学院,河北保定071000 [2]河北省林木种质资源与森林保护重点实验室,河北保定071000

出　　处：《蚕业科学》2023年第4期299-312,共14页ACTA SERICOLOGICA SINICA

基　　金：河北省自然科学基金项目(C2019204257);河北省高等学校科学技术研究项目青年基金项目(QN2019052)。

摘　　要：通过对7个桑树品种霜桑叶不同经霜时间(5 d、10 d、15 d)21个指标的测定,探究桑树叶片经霜过程中营养品质、功能性成分和抗氧化活性的变化规律。结果表明:不同经霜时间霜桑叶品质发生显著变化(P<0.05)。经霜5 d时,霜桑叶叶绿素a含量、叶绿素b含量、类胡萝卜素含量、总叶绿素含量和清除ABTS自由基能力较高;经霜10 d时,霜桑叶可溶性糖含量、绿原酸含量和单宁含量较高;经霜15 d时,霜桑叶含水率、可溶性蛋白含量、氨基酸含量、黄酮含量、MDA含量、SOD活性和POD活性较高。氨基酸含量、黄酮含量、MDA含量、SOD活性和POD活性在经霜期内随经霜时间增加呈上升趋势。对21个指标进行主成分分析,从中提取了6个主成分,其累计方差贡献率达到85.962%,能够较好地体现霜桑叶品质的大部分信息;通过建立主成分综合模型计算样品综合得分,确定经霜时间对桑叶多酚含量、绿原酸含量、总叶绿素含量、抗坏血酸含量、CAT活性、清除ABTS自由基能力、清除DPPH自由基能力等7个霜桑叶品质指标的影响最大。本研究为霜桑叶适时采收及开发利用提供了理论依据。Through measuring 21 indexes of frosted mulberry leaves of seven mulberry varieties after different frosting time(5 d,10 d,15 d),the changes of nutrients,functional components and antioxidant activity of mulberry leaves dur⁃ing frosting were explored.The results showed that the quality of frosted mulberry leaves changed significantly after differ⁃ent frosting time(P<0.05).The contents of chlorophyll a,chlorophyll b,carotenoids,total chlorophyll and ABTS free radical scavenging ability of frosted mulberry leaves were higher after 5 d of frosting.The contents of soluble sugar,chlo⁃rogenic acid and tannin of frosted mulberry leaves were higher after 10 d of frosting.The contents of water,soluble pro⁃tein,amino acid,flavonoids,MDA,as well as SOD and POD activity of frosted mulberry leaves were higher after 15 d of frosting.Generally speaking,the amino acid content,flavonoids content,MDA content,SOD activity and POD activity in⁃creased with the frost time.Principal component analysis was carried out on 21 indexes,and 6 principal components were extracted from them,with the cumulative variance contribution rate reaching 85.962%,which can better reflect most of the information about the quality of frosted mulberry leaves.The comprehensive score of the sample was calculated by establishing the comprehensive model of principal components.It was finally determined that frosting time had the greatest impact on the seven quality indicators of frosted mulberry leaves,including polyph⁃enol content,chlorogenic acid content,total chlorophyll content,ascorbic acid content,CAT activity,the ability to scav⁃enge ABTS free radicals,and the ability to scavenge DPPH free radicals.This study provides a theoretical basis for timely harvesting,development and utilization of frosted mulberry leaves.

关 键 词：霜桑叶 桑椹品种 桑叶品质 主成分分析 

分 类 号：S886.9[农业科学—特种经济动物饲养]