不同采收及加工方式对穿心莲药材质量的影响

Effects of different harvesting and processing methods on quality of Andrographis Herba

通过考察穿心莲的生长期、产地加工、营养器官和全草分段等因素对药材质量的影响,为穿心莲优质药材的生产提供科学依据。采用"一测多评"法,同步测定78份样品中穿心莲内酯(andrographolide,AD)、新穿心莲内酯(neoandrographolide,NAD)、14-去氧穿心莲内酯(14-deoxyandrographolide,14-DAD)和脱水穿心莲内酯(dehydroandrographolide,DHAD)的含量,并分别采用直观分析、聚类分析和偏最小二乘法判别分析(PLS-DA)等统计学方法进行数据分析和挖掘。结果表明:穿心莲按照快速生长期(Ⅰ期)、枝叶茂盛期(Ⅱ期)、花蕾期(Ⅲ期)、花盛期(Ⅳ期)、盛果期(Ⅴ期)和果期后期(Ⅵ期)6个生长期来划分,4种二萜内酯总量(TC)在Ⅰ~Ⅲ期内较为稳定,Ⅳ期开始下降,Ⅴ期下降最为迅速,Ⅵ期降至最低,因此穿心莲药材的采收期以花蕾期为最佳。产地加工时,尽管晒干和阴干对TC的影响较小,但与晒干比较,阴干样品中AD含量降低,DHAD和NAD含量升高,即阴干过程可以导致AD的分解和转化。因此,在天气条件允许的情况下,产地加工尽量采用晒干法进行干燥。AD,DHAD和TC在穿心莲不同全草分段和营养器官的分布分别为:全草上部>全草中部≈全草>全草下部,叶>全草>茎,且4种二萜内酯在叶和全草中的含量远高于茎,建议药材采收时以全草的上部和中部或含叶以上部位为佳,以保证其叶的占比要求。

The effects of the growing periods, processing methods, nutritive organs and cut parts of the herbs on the quality of Andrographis Herba have been studied, which could provide scientific basis for producing high-quality crude materials of Andrographis Herba. A quantitative analysis of multi-components by single-marker(QAMS) method was used to simultaneously determine 4 diterpene lactones of andrographolide(AD), neoandrographolide(NAD), 14-deoxyandrographolide(14-DAD), and dehydroandrographolide(DHAD) in 78 batches of Andrographis Herba samples. Visual analysis, clustering analysis and partial least squares discrimination analysis(PLS-DA) were used for data processing and mining. The growing periods of Andrographis Herba were divide into the rapid growing stage(Ⅰ), the luxuriant foliage stage(Ⅱ), the bud stage(Ⅲ), the flower stage(Ⅳ), the fruiting stage(Ⅴ) and the later fruiting stage(Ⅵ), six ones in total. The results showed that the total contents of 4 diterpene lactones(TC) kept almost constant in growing periods of Ⅰ-Ⅲ, began to fall off in growing period Ⅳ, decreased rapidly in growing period Ⅴ and reduced to minimum in growing period Ⅵ. Therefore, the best harvesting period for Andrographis Herba was the bud stage. For the processing methods, none significant difference occurred for TC between drying by the sun and drying in the shade. However, in comparison of the samples dried by the sun, the samples dried in the shade exhibited lower content of AD, nonetheless, the higher contents of DHAD and NAD, indicating that the process of drying in the shade may lead to the decomposition and transformation of AD. Therefore, when the weather conditions permitted, the method drying by the sun should be used. The distributions of AD, DHAD and TC in the different cut parts and nutritive organs were determined as follows: upper cut parts > middle cut parts ≈ entire herbs > lower cut parts, leaves > entire herbs > stems. Furthermore, the contents of 4 diterpene lactones in leaves and herbs were much higher than those in stems. Therefore, it was suggested that the upper and middle cut parts of the herbs or the parts containing leaves should be preferred for harvesting to ensure the proportion of the leaves in Andrographis Herba.