Study On Chemical Constituents Of Apocynum Venetum In Xinjiang Altay

The world’s largest and best national reserve for wild Apocynum venetum is located in Altay, Xinjiang Province in China, GauBau company has spent more than ten years in the development of Apocynum venetum-related products. Till now health care products as well as textile products have been marketed. However, there was a lack of systemic research about the chemical constituents of Apocynum venetum and no report has been found for the classification of Apocynum venetum strains according to the method of chemotaxonomy. In this study, the leaves of A. hendersonii (Hook.f.) woodson.(AH) with five different phenotypes in the same habitat and the leaves of Apocynum venetum L.(AL) in three different habitats in the Altay area were collected as research materials and analyzed for flavonoids, amino acids (AA), fatty acids (FA), lipids and mineral elements. The genetic relationship analysis of AH was carried out with the obtained values combined with chemotaxonomy. The aim of this study was to offer basic information and scientific evidence for the classification of genetic resources, high quality breeding and artificial cultivation of Apocynum venetum. The main results obtained in this study are as follows:1. The flavonoid, amino acid and fatty acid levels all varied among the five different phenotypes of AH. The contents of flavonoids were:White AH (W-AH)(3.59 mg/g)> Medium Fine Leaf AH (ML-AH)(2.29 mg/g)> Cyan Stem AH (CS-AH)(1.71 mg/g)> Red Stem AH (RS-AH)(1.34 mg/g)>Special fine Leaf AH (SL-AH)(0.97 mg/g). Among the eight flavonoids, rutin showed the highest level with a percent of 54.3%-84.5% of total flavonoids. The amino acid contents were:SL-AH>CS-AH>RS-AH>W-AH>ML-AH and the range was between 16.07% and 19.31%. The content of fatty acids in the five materials was in the range of 357.24 mg/100g-612.15 mg/100g. Unsaturated fatty acids account for 55.29%- 63.89% of total fatty acids and trans-fatty acids was less than 1.5%. Since the ratio of ω-3 fatty acid to ω-6 fatty acid was close to 4, the plants showed high nutritive values.2. The five different phenotypes of AH were preliminarily divided into three groups according to the characteristics of their chemical constituents. The first group includes RS-AH and SL-AH that contain low level of flavonoids and FA; the second group consists of CS-AH and ML-AH that showed medium level of flavonoids, high level of FA, and high level of AA; the third group was W-AH that displayed high level of flavonoids, medium level of FA and low level of AA. All groups have the same FA varieties and synthetic routes, which indicates that these plants might have close affinities to each other.3. Soil environment exhibited great effects on the content of chemical composition of AL leaves. The total flavonoid ranged from 1.1195 mg/g to 1.3342 mg/g in the leaves of AL from the three habitats, and the content in RS-AH was significantly higher than that in other habitats (P<0.05). Rutin showed the highest content level (0.4181 mg/g-0.8075 mg/g) among the eight types of flavonoids, which was in agreement with the study of AH. The amino acid content was 14.34%-17.33%. All these AL leaves contain the eight types of saturated fatty acids and six types of FA, but these components differ in content. Compared with AH in Tushan area, AV exhibited high level of epicatechin, quercetin, kaempferol and hyperoside at 0.0307 mg/g,0.1832 mg/g,0.0177 mg/g and 0.1462 mg/g, respectively. In contrast, AH has a higher level in rutin (1.4430 mg/g) and total flavonoid (1.9799 mg/g).4. Soil organic carbon and total nitrogen displayed a positive correlation with rutin, total flavonoid and polyunsaturated fatty acids (PUFA) compositions in the leaves of AL(P<0.05), whereas soil pH was negatively correlated with rutin and PUFA(P<0.05). Soil available sodium had a significant correlation with total AA and flavonoid (P<0.05). Therefore, according to the high saline-alkali and drought characteristics of soil in this research area, application of soil organic manure and irrigation could be important in influencing soil fertility, lowing soil pH and improving soil quality.