紫苏叶挥发油化学型和组分影响因素探究Ⅰ——不同生长发育期

Research on effects of chemotype and components of Perilla frutescens leaf volatile oil I: different phenological periods

该论文以普遍存在的PK型、PA型及稀有的PL型3种紫苏种质为研究对象。在紫苏生长的营养期、开花期、果熟期3个时期进行紫苏成熟叶样品采集,同时分为1 d之中早7点、午12点、晚18点3个时间点,对其挥发油进行了提取(水蒸汽蒸馏法)和GC-MS分析,3种化学型的样品挥发油得率在0.08%~0.96%,不同生长时期挥发油得率大致为营养期>开花期>落叶期,营养期挥发油得率:PA型>PK型>PL型。各化学型类别不受生长发育影响,表明遗传因素决定了化学型。PA和PK型的特征成分和主要成分相对含量都比较稳定,而PL型的特征成分随生长发育大幅度降低,组成中还存在大量各类成分代谢的上游化合物,表明该化学型可能具有原始性和多变性。PA型特征成分紫苏醛相对含量各个时期基本上从早到晚逐渐降低。PK型特征成分紫苏酮在营养期和开花期中午相对含量高于早晚样品,果熟期则相反。PL型特征成分紫苏烯相对含量在营养期和果熟期都是中午最高,开花期则是傍晚样品最高。综合挥发油得率和主要成分相对含量,PA型的最佳采收时间在营养期的早晨采收;PK型的最佳采收期在各期午前均可;PL型的最佳采收期在营养期的晚上采收最好。

This experiment researched on three kinds of Perillafrutescens including the widespread PK, PA and rare PL chemotype. The Perilla samples were the mature leaves collected in nutrition, flowering and frutescence three different phenological periods, and at 7 am, 12 pm and 6 pm three day time. The volatile oil was extracted by steam distillationand analyzed by GC-MS, as a result, the three chemotypc samples＇volatile oil yield was between 0. 08% and O. 96% ; volatile oil yield of different growth period was as follow： nutrition 〉 flowering 〉 fructescence, and the volatile oil yield of nutrition period ： PA type 〉 PK type 〉 PL type. Each chemotype was not affected by the growth and development, indicating that the chemotype is determined by genetic factors. Characteristic and main components of PA and PK type are relatively stable, and the characteristic components of PL type are significantly decreased with thegrowth. There are still a large number of upstream metabolism components, and the chemical type may have their primitiveness and changeability. The relative content of perillaldehyde, characteristic components of PA type, is basically decreased from morning to night, in all the period. The relative content of perillaketone, characteristic components of PK type, in nutrition and flowering period, when samples were collected at 12 noon is relatively higher than that at 7 am and 6 pro, and contrary to samples collected in frutescence period. The relative content of perillene, characteristic components of PL type, in nutrition and fl＇utescence period are highest at 12 noon, while in flowering period is highest at 6 pm. According to the volatile oil yield and relative content of maincomponents, the best harvest time of PA type is in the morning of the nutrition period ; the best harvest time of PK type is in the morning of all the period ; and the best harvest time of PL type is at dusk of the nutrition period.