刺梨及其近缘种质叶片主要活性物质含量及抗氧化性分析

为明确刺梨及其2个近缘种质无籽刺梨和无刺刺梨叶片中活性物质含量变化及其对抗氧化能力的贡献,本研究以刺梨、无籽刺梨和无刺刺梨为试验材料,测定其不同叶龄叶片(幼叶、成熟叶和老叶)中维生素C(Vc)、总三萜、总酚、总黄酮含量及超氧化物歧化酶(SOD)活性变化,并用铁离子还原(FRAP)、2,2'-联氨-二(3-乙基-苯并噻唑-6-磺酸)二铵盐(ABTS)和1,1-二苯基-2-苦肼基(DPPH)3种体系分析其体外抗氧化能力,同时对5种抗氧化活性物质进行主成分分析。结果表明,3个材料的不同叶龄叶片中,总酚、总黄酮、Vc含量和SOD活性变化以及3种抗氧化活性均依次表现为成熟叶>幼叶>老叶,而总三萜含量均在老叶中为最高;3个试验材料成熟叶中,无刺刺梨的总酚含量及其对ABTS自由基的清除能力、刺梨的Vc含量及其对DPPH自由基的清除能力,以及无籽刺梨的SOD活性及其对FRAP抗氧化能力均高于其他2个材料,刺梨老叶中的总三萜含量显著高于其他2个材料。相关性分析表明,总酚、总黄酮、Vc与3种抗氧化方法测定结果呈显著正相关;主成分分析表明,成熟叶中具有抗氧化能力的5种活性物质对抗氧化能力贡献依次表现为总酚、Vc>总三萜、SOD>总黄酮,且3种主成分的累计贡献率达90%以上。本研究结果为了解和开发利用上述3个蔷薇属种质叶片功能成分提供了理论依据。

Analysis of Main Active Substances and Antioxidant Activities in Leaves of Rosa roxburghii and the Two Related Species

This study aimed to understand the changes of the active substance contents and their contributions to the antioxidant properties in leaves of Rosa roxburghii Tratt. and its two related germplasm R. sterilis S.D. Shi and R. roxburghii f. Eseiosa Ku. The contents of vitamin C (Vc) total triterpenoids, total phenols, total flavonoids, and superoxide dismutase (SOD) were determined in leaves of three developmental stages (young leaves, mature leaves and old leaves) of the three germplasms. The iron ion reduction (FRAP), 2,2'-amino-bis (3-ethyl-benzothiazoline-6-sulfonate) ammonium salt (ABTS) and1,1-, two phenyl,-2-hydrazine group (DPPH) were used to evaluate the antioxidant activity in vitro and the principal component analysis of five kinds of antioxidant active substances were also made.The results showed that the changes of total phenolics, total flavonoids, Vc contents and SOD activities and the three antioxidant activities presented mature leaves> young leaves> old leave in 3 different leaf ages of 3 materials, while the total triterpenoids have the highest content in the old leaves. In mature leaves of 3 materials, the total phenolic contents and ABTS·+ free radical scavenging capacity of R. roxburghii f. Eseiosa, the Vc contents and DPPH·+ free radical scavenging capacity of R. roxburghii and the SOD activity and FRAP free radical capacity of R. sterilis were higher than the other two materials, whereas the total triterpene contents in old leaves of R. roxburghii were significantly higher than the other two materials. Correlation analysis showed that total phenol, total flavonoids and Vc were significantly positively correlated with the value of three antioxidant methods. The principal component analysisindicated that the five active compounds with antioxidant capacity in mature leaves contributed to the antioxidant properties showed total phenols and Vc > total triterpenes and SOD > total flavones, and the cumulative contribution rate of the three components were more than 90%. The above results provide important theoretical basis for understanding and developing the functional components of three Rosa germplasms leaves.