Chemical Constituents From Petrosimonia Sibirica L. And Research On Its Antimicrobial And Antioxidant Activities

Petrosimonia sibirica L.(the genus Petrosimonia, family Chenopodiaceae) is an annual herbaceous plant, which grows mostly in arid and saline areas. In China, it is found only in Xin Jiang. It is used in desert area as sand fixing plant providing substantial forage yields. To the best of our knowledge, there are few reports on its chemical composition and bioactivity.This research is focus on isolating chemical composition and evaluating the bioactivity of the parts of compounds from P. sibirica L. The chemical composition was separated from chloroform extract and ethyl acetate extract based on bioassay-guided separation. Then these compounds were evaluated by the antibacterial, antioxidant bioactivity. The main results are follows.1. By bioassay-guided fractionation, thirteen compounds were isolated and purified by TLC, column chromatography on silica gel, and Sephadex LH-20 column chromatography from the chloroform extract and ethyl acetate extract of P. sibirica L. Based on the spectrometric analysis of their 1H-NMR, 13C-NMR and MS data, eleven compounds were identified as 3-(4-chlorophenyl)-1-phenyl-1H-pyrazole-4-carbaldehyde, Methyl-4-hydroxyl benzoate, Nonacosane, 4-hydroxybenzaldehyde, 4-Hydroxybenzoic acid, Methyl-3-hydroxy-4-methoxybenzoate, β-hydroxypropiovanillone, α-spinasterone, 2-hydroxy benzoic acid,adenosine and dibutyl phthalate. Ten of these compounds were isolated from P. sibirica L. for the first time.2. Seven strains of bacterial and two strains of fungi were used as the test microorganism,and the MIC and IC50 values were used to evaluate the antimicrobial activity of the five compounds which were isolated from P. sibirica L. It was showed in the antibacterial test that most of the isolated compounds strongly inhibited the growth of the microorganisms.3-(4-Chlorophenyl)-1-phenyl-1H–pyrazole-4-carbaldehyde(A) and 4-Hydroxybenzoic acid(K) exhibited inhibitory activity on most of the selected bacterial strains.4-hydroxybenzaldehyde exhibited the strongest inhibitory effect on Soil agrobacteria,Alternaria solani, with MIC value of 0.05, 0.05 mg/m L, and IC50 value of 0.0351,0.0166 mg/m L; and it was found to be more effective than the positive control with the value of MIC were 〉1, 0.2 mg/m L, and IC50 were 0.0950, 0.1631 mg/m L. The above mentioned compounds strongly inhibited Escherichia coli. 4-Hydroxybenzoic acid exhibited effective inhibition against Xanthomonas vesicatoria, Escherichia coli, and Bacillus subtilis, which the value of MIC were 0.2, 0.05, 0.05 mg/m L, and IC50 were 0.1197, 0.0449, 0.0454 mg/m L.They are more effective than the positive control. Methyl-4-hydroxybenzoate more effective than the positive control, with IC50 was 0.0275 mg/m L. 3-(4-Chlorophenyl)-1-phenyl-1H-pyrazole-4-carbaldehyde exhibited the best inhibition of Bacillus subtilis and Methyl-4-hydroxybenzoate exhibited the best inhibition of Staphylococcus epidermidis among the five compounds, but are weaker than positive control.It was showed in the antioxidant test that most of the compounds exhibited some antioxidant potential. β-hydroxypropiovanillone exhibited more antioxidant potential with thevalue of 3.728 mmol/g, still weaker than the two positive controls(5.593, 12.502 mmol/g) in the method FRAP. Howere, more effective than the positive control with the value of 0.2826,1.2692 mg/m L in the method DPPH, β-hydroxypropiovanillone with IC50 value of 0.1948mg/m L.