7种菜用甘薯品种（系）多酚类物质含量动态变化分析

多酚类物质是菜用甘薯中一种重要的功能性保健成分,以绿原酸类化合物为主,它们对提升菜用甘薯食用和加工品质起着重要的作用。采用 Folin-Ciocalteu法和高效液相色谱法分析了7份菜用甘薯品种（系）6个不同时期的总多酚以及绿原酸类化合物含量。结果表明,不同品种（系）的菜用甘薯中总多酚以及绿原酸类化合物的含量受采样时间的影响极显著,并呈现动态变化,即栽后45~85 d,各品种（系）的各类物质变化趋势相同,先增加后降低,在65 d达到最大值,在栽后85~140 d变化趋势存在差异。对7份菜用甘薯品种（系）的6个不同时期总多酚以及绿原酸类化合物含量进行变异分析,结果表明5-O-咖啡酰奎尼酸（5-O-caffeoylquinic acid, 5-CQA）、3,4-O-二咖啡酰奎尼酸（3,4-di-O-caffeoylquinic acid, 3,4-diCQA）、3,5-O-二咖啡酰奎尼酸（3,5-di-O-caffeoylquinic acid, 3,5-diCQA）和4,5-O-二咖啡酰奎尼酸（4,5-di-O-caffeoylquinic acid, 4,5-diCQA）含量变异幅度大,而总多酚含量变异幅度相对较小,其变异系数范围分别为30.80%~59.88%、45.18%~112.90%、45.19%~114.11%、41.82%~118.62%、19.82%~40.04%。总多酚以及绿原酸类物质含量的影响因素分析表明,总多酚以及绿原酸类化合物含量受采样时间、品种（系）以及两种因素交互作用的影响极显著,且总多酚含量与绿原酸类化合物含量存在极显著正相关。对菜用甘薯多酚类物质含量变化规律的研究,可为菜用甘薯叶的产业化开发利用奠定基础。

Dynamic Content Variation Analysis of Polyphenols in Seven Leafy Sweet Potato Varieties (Lines)

Polyphenol related materials which are mainly constituted by chlorogenic acids (CGAs) are one of the most important health protection components in leafy sweet potato. They play important roles for improving leafy sweet potato taste and processing quality. In this study, Folin-ciocalteu and HPLC methods were employed to determine the contents of total polyphenols and chlorogenic acids in seven leafy sweet potato varieties (lines) at 6 stages. The content of total polyphenols and CGAs in different varieties (lines) was significantly affected by stages and exhibited dynamic variation. All varieties (lines) showed the same content change trend from 45 days to 85 days after planting. They first increased and then decreased, reaching the maximum level in 65 days, however, there were differences in the change trend from 85 days to 140 days after planting. The variation coefficient of the substances demonstrated that 5-CQA (5-O-caffeoylquinic acid), 3,4-diCQA (3,4-di-O-caffeoylquinic acid), 3,5-diCQA (3,5-di-O-caffeoylquinic acid) and 4,5-diCQA (4,5-di-O-caffeoylquinic acid) displayed a wider range variation than total polyphenols, with the range of 30.80% to 59.88%, 45.18% to 112.90%, 45.19% to 114.11%, 41.82% to 118.62% and 19.82% to 40.04%, respectively. The overall variation analysis inferred that the total polyphenols and chlorogenic acids were significantly affected by sampling times, varieties (lines) and the cross effect of both. Moreover, the total polyphenols and CGAs were significantly positively correlated. The investigation of polyphenol related materials of leafy sweet potato could lay a foundation for industiral exploration.