ABSTRACT
OBJECTIVE: To find out the distribution of ursolic acid and oleanolic acid in fresh leaves, fallen leaves and flowers of Eriobotrya japonica Lindl, and to explore the variation in contents of the triterpene acids in the leaves at different harvest time. METHODS: Samples were collected in the campus once every month for 12 months. Determination of ursolic and oleanolic acid was carried out by ultra-high performance liquid cromatography (UPLC) with an acquity BEH 18 column (2.1 mm × 100 mm, 1.7 μm) using methanol-water-glacial acetic acid-triethylamine (250:50:0.10:0.05) as the mobile phase. The flow rate was 0.25 mL · min-1. The detection wavelength was set at 210 nm. RESULTS: The contents of ursolic and oleanolic acids in Erobotrya japonica leaves were significantly higher compared with those in Erobotrya japonica flowers. The contents of the two triterpene acids in the fallen leaves were higher than those in the fresh leaves. The annual curves of dynamic changes of the two triterpene acids contents in Erobotrya japonica leaves showed that the total triterpene acids contents in the Erobotrya japonica leaves collected at the different time varied from 0.874% to 0.988%. CONCLUSION: The distribution of the contents of ursolic and oleanolic acid in the fresh leaves, fallen leaves and flowers was different, and there was minor variation in the contents of the two triterpene acids in fresh Erobotrya japonica leaves collected at the different harvest time. This study therefore provides evidence that the Erobotrya japonica leaves included in Chinese Pharmacopoeia (2010 edition, Volume I) can be harvested all the year round. Furthennore, the results suggest that the optimal harvesting time oi Erobotrya japonica leaves should be between pre-defoliation period and defoliation period.
ABSTRACT
Objective To understand the level and distribution of antibody F1 against plague in population of Ningxia natural plague foci in 2007 and 2008. Methods Seven hundred and eighteen blood samples were collected in five major cities and counties of natural plague foci, and 475 blood samples were collected in nonplague area as control group. Conventional indirect hemagglutination, colloidal gold test, and enzyme-linked immunoassay were employed to test the antibody. If the result was tested positive by more than two methods used then the result was defined as positive. Antibody titer that did not reach the positive standard was defined as suspected samples. Results A total of 718 serum samples were tested, the results showed that 9 samples were positive (antibody titer was 1:16 - 1:64), the positive rate was 1.25%(9/718), suspected samples was 28, the detection rate was 3.90%(28/718). Four hundred and seventy-five serum samples in the non-plague area were all negative by the three methods. There was a significant difference of antibody F1 positive rate between residents in historical epidemic area and history nonepidemic area(χ2 = 4.44, P< 0.05). There was no statistical significance of the positive rate[1.25%(9/718), 1.25%(9/718),2.51%(18/718)]among the three methods used(χ2 = 1.91, P> 0.05). Conclusion There still exists a certain proportion of Fl antibody positive people in Ningxia natural plague foci, and these people are distributed in areas where several animal plague prevalent in recent years.