ABSTRACT
The study is aimed to explore the effect of different water on the content of total saponins,astragaloside Ⅳ and gene expression in the growth of Astragalus membranceus. In this study, one-year-old A. membranaceus was used as the experimental material, by pot culture different water treatments were simulated at herbal garden in Jilin Agricultural University. The content of astragaloside Ⅳ was determined by HPLC and the total saponins by UV spectrophotometry. With 18 S RNA as a reference gene, fluorescent quantitative PCR was applied to analyze the eight key enzymes in astragalus saponin synthesis pathway AACT,HMGS,HMGR,IDI,FPS,SS,SE,CAS expression. With the decrease of soil water, the content of astragaloside Ⅳ in the root tissue of A. membranaceus showed an increasing trend, up to 1.46 mg·g~(-1). The total saponin content tended to increase, up to 6.80 mg·g~(-1). The results of relative expression of genes showed that the eight genes showed different effects at different water. With the change of soil water content, the amount of(AACT,IDI,SS) relative expression in drought stress group firstly increased and then decreased, then increased, and then decreased. The amount of(HMGS,HMGR,FPS) relative expression in drought stress group increased firstly and then decreased. The amount of(SE,CAS) relative expression in drought stress group increased firstly and then decreased, and continued to decrease after rehydration. The expression of key enzyme genes involved in the synthesis of astragaloside was influenced by each other, and the expression of key enzyme in roots showed a correlation with the content of astragaloside. Correlation analysis showed that there was a very significant positive correlation between HMGR gene and total saponins content in drought stress group and a significant negative correlation between content of CAS and total saponins. The contents of FPS,SE,CAS and astragaloside Ⅳ were very significantly and negative correlated. The relationship between other genes and quality was positive. Therefore, HMGR, FPS, SE and CAS genes have significant effects on the regulation of saponin content under water control. On the 15 th day after water regulation, the total amount of astragaloside and total saponins reached the highest value and could be harvested.
Subject(s)
Astragalus Plant , Metabolism , Chromatography, High Pressure Liquid , Droughts , Saponins , Stress, Physiological , Triterpenes , WaterABSTRACT
AIM: To investigate the effects of oral administration of Astragalus membranceus, mung bean and arsenolite on the toxic of the arsenolite induced rats and the possible mechanisms with metallothionein (MT). METHODS: All the rats were oral administration with arsenolite. The Astragalus membranceus and mung bean were compared with the cadmium chloride which induced MT synthesis. The contents of MT were determined by cadmium saturation method, the liver mRNA levels for MT 1, MT 2 were detected by RT PCR. The protective effects of renal and liver were observed by testing alanine aminotransferase (ALT), blood urea nitrogen (BUN) and serum creatinine (SCR). RESULTS: The contents of MT were accorded with the mRNA expression of MT 1, MT 2. Arsenolite, Astragalus membranceus and mung bean could induce the synthesis of MT, but the contents of MT which arsenolite induced were trace. The contents of MT significantly increased after oral administration of Astragalus membranceus and mung bean, especially in the Astragalus membranceus group (P