不同猕猴桃品种果实发育过程中总酚和类黄酮含量及抗氧化活性的动态变化

Dynamic changes in total phenols, flavonoids and antioxidant capacity during fruit development of different kiwifruit cultivars

【目的】探讨不同猕猴桃品种果实发育过程中总酚、类黄酮含量及抗氧化活性的动态变化差异。【方法】以江西主栽的美味猕猴桃'金魁’和中华猕猴桃'红阳’以及本课题组自主选育的毛花猕猴桃'赣猕6号’为试材,对果实生长发育过程中总酚、类黄酮含量和FRAP抗氧化能力、清除羟基自由基(·OH)、DPPH自由基(DPPH·)和超氧阴离子自由基(·O2-)的能力进行检测分析。【结果】3个猕猴桃品种果实总酚和类黄酮含量在果实生长发育过程中大体呈现由高到低的变化趋势;但不同品种其含量差异显著,尤其'赣猕6号’总酚含量高于其他两个品种十几倍。对抗氧化活性检测发现',赣猕6号’比其他两个品种具有较强的FRAP抗氧化能力和清除超氧阴离子自由基(·O2-)能力。相关性分析显示',赣猕6号’清除·OH和·O2-能力与总酚、类黄酮含量存在极显著或显著相关性',金魁’FRAP抗氧化能力与总酚、类黄酮含量存在极显著和显著相关性,而'红阳’FRAP抗氧化能力、清除DPPH·能力分别与总酚、类黄酮含量存在显著和极显著相关性。【结论】猕猴桃果实含有丰富的酚类物质,随着果实的生长发育呈现逐渐降低的趋势。猕猴桃抗氧化能力与总酚、类黄酮含量呈显著正相关。毛花猕猴桃'赣猕6号’比美味猕猴桃'金魁’和中华猕猴桃'红阳’具有更高含量的酚类物质和更强的抗氧化能力。本试验为猕猴桃优良品种的推广、野生资源发掘、新品种选育、天然抗氧化保健药物以及功能性食品的开发奠定了基础。

【Objective】Phenolics are rich in kiwifruit, especially in the fruit of Actinidia eriantha, butthere is not much research on this. The main aim of this study was to discover and analyze the dynamicchanges in the contents of total phenols, flavonoids and the antioxidant activity during the fruit develop-ment in different kiwifruit cultivars. At the same time, the relationship of the contents of total phenolsand flavonoids with antioxidant capacity was analyzed.【Methods】’Jinkui’(A. deliciosa) and’Hong-yang’(A. chinensis), the two main cultivars in Jiangxi, and’Ganmi-6’(A. eriantha), a new cultivarbred by our group, were selected as materials. Not less than 30 fruit with the same shape and uniformsize were randomly collected from the south side of the tree crown of the three cultivars every 15 daysfrom 30 d after blooming until the fruit ripened at 165 days after blooming. All the fruit were put in iceboxes and immediately brought back to the lab to test the contents of total phenols and flavonoids, theFRAP antioxidant ability and the scavenging capacity of hydroxyl radical(· OH), 1,1-dipphenyl-2-pic-rylhydrazyl radical(DPPH ·) and superoxide anion radical(· O2-) during the fruit development. The dif-ferences in the contents of total phenols and flavonoids as well as antioxidant capacity in all tested threecultivars were compared, and the correlation of the contents of total phenols and flavonoids with antioxi-dant capacity were analyzed.【Results】The results indicated that the contents of total phenols and flavo-noids in all the tested cultivars showed a similar change trend from high to low during fruit develop-ment. However, there were significant differences in the contents of total phenols and flavonoids in dif-ferent cultivars. The content of the total phenols in’Ganmi-6’was more than ten times higher than inthe other two cultivars. During the fruit development, the lowest content of total phenols in’Ganmi-6’was 4 660.6 mg · kg-1, while the maximum total phenol content in’ Jinkui’was 2 457.6 mg · kg-1 and2 143.3 mg · kg-1 in’Hongyang’. Content of flavonoids was lowest in mature fruit, which was 235.7 mg · kg-1, 190.0 mg · kg-1 and 173.1 mg · kg-1 in the fruit of’ Ganmi-6’,’ Jinkui’and’ Hongyang’,respectively. The results of antioxidant activity showed that the FRAP antioxidant ability decreasedwith the ripening of the fruit in’Hongyang’, but it fluctuated in the fruit of’Jinkui’, and the FRAP an-tioxidant ability at the ripening stage was lower than that of the young fruit. However, the FRAP antioxi-dant capacity of’Ganmi-6’in the whole process of fruit growth remained high with the FRAP value inthe range of 786.5 mg · kg-1-838.2 mg · kg-1, which was significantly higher than that in the other twocultivars from 90 days after blooming. Although the scavenging capacity of DPPH · in the fruit of’Gan-mi-6’was at a higher level, there was a slow change from low to high during the fruit development inthe three tested cultivars. The scavenging capacity of · OH in the fruit of’Jinkui’and’Hongyang’fluc-tuated slightly and the value of the ripe fruit was slightly lower than that of the young fruit. However,the scavenging capacity of · OH in the fruit of’Ganmi-6’gradually increased, and the value of 71.40%at 165 d after blooming was significantly higher than the value of 27.82% at 30 d after blooming. Thescavenging capacity of · O2-in the fruit of’Jinkui’and’Hongyang’changed gently during the earlystage of fruit development, then slightly declined at the middle stage of fruit development, and rose ob-viously at the ripe stage. The scavenging capacity of · O2-in the fruit of’Ganmi-6’gradually declined,and the value of 52.08% at 165 d after blooming was significantly lower than 65.29% at 30 d afterblooming. The result of the scavenging capacity of · O2-also showed that’Ganmi-6’had stronger anti-oxidant ability than the other two cultivars. Correlation analysis revealed that there were extremely sig-nificant positive correlations between · O2-scavenging capacity and the contents of total phenols and fla-vonoids, and significant positive correlations between · OH scavenging capacity and the contents of to-tal phenols during the’Ganmi-6’fruit development. During the’Jinkui’fruit development, there werealso significant positive correlations between the FRAP antioxidant ability and the contents of total phe-nols and flavonoids. Significant positive correlations were also found between the FRAP antioxidantability and the contents of total phenols and flavonoids in’Hongyang’. In addition, there were extreme-ly significant positive correlations between DPPH · scavenging capacity and the contents of total phe-nols and flavonoids during the’Hongyang’fruit development.【Conclusion】The contents of phenolicswere high in the three tested kiwifruit cultivars and gradually decreased during the fruit development.The contents of total phenols and flavonoids were significantly correlated with the fruit antioxidant ca-pacity. However, the contents of phenolics and the antioxidant capacity were significantly differentamong cultivars.’Ganmi-6’had higher phenolics contents and stronger antioxidant capacity than’Jinkui’and’Hongyang’.