不同叶菜型甘薯品种茎尖绿原酸含量及清除DPPH·能力

Chlorogenic Acid Contents in Shoot-Tips of Different Vegetable-Use Sweetpotato Varieties and Their DPPH-Scavenging Capacities

【目的】研究叶菜型甘薯茎尖绿原酸的含量及其清除DPPH·能力,为叶菜型甘薯的品种筛选、栽培及产业化提供理论依据。【方法】在6个不同生长期分别采收广菜薯2号、莆薯53和福薯7-6的茎尖,测定并分析茎尖叶片、叶柄和茎绿原酸含量及其与DPPH·清除能力之间的相关性。【结果】(1)6次采收期的不同甘薯品种茎尖绿原酸平均含量大小为:广菜薯2号(0.2920%fb)>莆薯53(0.2750%fb)>福薯7-6(0.1638%fb),其中叶片(0.3539%fb)>茎(0.1444%fb)>叶柄(0.1173%fb),叶片含量是叶柄和茎平均值的2.70倍;广菜薯2号、莆薯53和福薯7-6茎尖前3个采收时期绿原酸的平均含量分别是后3个时期的2.22、2.68和2.41倍,其中叶片、叶柄和茎前3次采收期绿原酸含量的平均值分别是后3次采收期的2.49,2.53和2.20倍。差异均达到显著水平。(2)根据3个品种6次采收期的平均值计算,叶片对茎尖绿原酸含量的贡献率为73.64%,叶柄为11.96%,茎为14.41%。(3)茎尖6次采收期的DPPH·清除能力平均大小为:广菜薯2号(34.99%)>莆薯53(31.05%)>福薯7-6(18.83%),其中叶片(32.52%)>茎(23.64%)>叶柄(17.91%);前3个采收时期的茎尖、叶片、茎和叶柄的DPPH·平均清除能力分别是后3个时期的1.91、2.02、1.69和1.99倍。【结论】叶菜型甘薯茎尖绿原酸含量在品种、部位和采收期间有显著差异;DPPH·清除能力与绿原酸含量具有显著或极显著正相关。因此,在叶菜型甘薯品种选育、栽培和产业化过程中要充分考虑茎尖绿原酸含量的变化特点。

【Objective】 Sweetpotato vine is composed of 3 parts,namely leaf,petiole and stem.It has received more and more attentions from the researchers,consumers,and are popular in vegetable market because sweetpotato vine is an excellent source of antioxidative polyphenolics which have anthocyanins and phenolic acids such as chlorogenic acid,and is superior in this regard to other commercial vegetables.So,the differences in chlorogenic acid contents in shoot-tips among varieties,parts and topping times of vegetable-use sweetpotato and their DPPH-scavenging capacities were studied in present paper.【Method】 The contents and DPPH-scavenging capacities of chlorogenic acid in leaves,petioles and stems of shoot tips of 3 vegetable-use sweetpotato varieties Guangcaishu No.2,Pushu 53 and Fushu 7-6 at 6 topping times after transplanting were determined and the correlationship between the chlorogenic acid content and its DPPH-scavenging capacity was analyzed.【Result】 The order of 3 varieties about their average chlorogenic acid contents in shoot tips during 6 topping times was Guangcaishu No.2（0.2920%fb）Pushu 53（0.2750%fb）Fushu 7-6（0.1638%fb）,and the order of 3 parts of shoot tips was leaf（0.3539%fb）stem（0.1444%fb）petioles（0.1173%fb） and the average chlorogenic acid content in leaves was 2.70 times the average of chlorogenic acid contents in petioles and stems.The average chlorogenic acid contents during the former 3 topping times in shoot tips of Guangcaishu No.2,Pushu 53 and Fushu 7-6 were 2.22,2.68 and 2.41 times those during the latter 3 topping times,respectively.And the average chlorogenic acid contents during the former 3 topping times in leaf,petiole and stem of shoot tips were 2.49,2.53 and 2.20 times those during the latter 3 topping times,respectively.The above differences in chlorogenic acid content were all significant.The significant variations of chlorogenic acid contents among varieties,parts and topping times were derived partly from the variety,and the effect of part,topping time and their interactions were also significant.73.64% of chlorogenic acid in shoot tips was distributed in leaves,11.96% in petioles and 14.41% in stems.The order of average DPPH-scavenging capacities of shoot tips of the 3 varieties during 6 topping times was Guangcaishu No.2（34.99%）Pushu 53（31.05%）Fushu 7-6（18.83%）,and the order of 3 parts was leaf（32.52%）stem（23.64%） petioles（17.91%）.The average DPPH-scavenging capacities during the former 3 topping times in shoot tips,leaf,stem and petiole were 1.91,2.02,1.69 and 1.99 times those during the latter 3 topping times,respectively.The DPPH-scavenging capacities of shoot tips,leaf,stem and petiole were all significant positively correlated with their chlorogenic acid contents.【Conclusion】 There were significant differences in chlorogenic acid contents among different varieties,parts and topping times of vegetable-use sweetpotato and these differences had significant effects on the shoot tips DPPH-scavenging capacities.The behavior of chlorogenic acid content variation should be taken into account in the breeding,cultivation and industrialization of vegetable-use sweetpotato.