Objective:To assess antioxidant activities of different parts of Euphorbia hirta（E.hirta）,and to search for new sources of safe and inexpensive antioxidants.Methods:Samples of leaves,stems, flowers and roots from E....Objective:To assess antioxidant activities of different parts of Euphorbia hirta（E.hirta）,and to search for new sources of safe and inexpensive antioxidants.Methods:Samples of leaves,stems, flowers and roots from E.hirta were tested for total phenolic content,and flavonoids content and in vitro antioxidant activity by diphenyl-1-picrylhydrazyl（DPPH） assay and reducing power was measured using cyanoferrate method.Results:The leaves extract exhibited a maximum DPPH scavenging activity of（72.96±0.78）%followed by the flowers,roots and stems whose scavenging activities were（52.45±0.66）%,（48.59±0.97）%,and（44.42±0.94）%,respectively.The standard butylated hydroxytoluene（BHT） was（75.13±0.75）%.The IC<sub>50</sub>,for leaves,flowers,roots,stems and BHT were 0.803,0.972,0.989,1.358 and 0.794 mg/mL,respectively.The reducing power of the leaves extract was comparable with that of ascorbic acid and found to be dose dependent. Leaves extract had the highest total phenolic content[（206.17±1.95） mg GAE/g],followed by flowers,roots and stems extracts which were（117.08±3.10） mg GAE/g,（83.15±1.19） mg GAE/g,and （65.70±1.72） mg GAE/g,respectively.On the other hand,total flavonoids content also from leave had the highest value[（37.970±0.003） mg CEQ/g],followed by flowers,roots and stems extracts which were（35.200±0.002） mg CEQ/g,（24.350±0.006） mg CEQ/g,and（24.120±0.004） mg CEQ/ g,respectively.HPTLC bioautography analysis of phenolic and antioxidant substance revealed phenolic compounds.Phytochemical screening of E.hirta leaf extract revealed the presence of reducing sugars,terpenoids,alkaloids,steroids,tannins,flavanoids and phenolic compounds. Conclusions:These results suggeste that E.hirta have strong antioxidant potential.Further study is necessary for isolation and characterization of the active antioxidant agents,which can be used to treat various oxidative stress-related diseases.展开更多
为研究经霜对桑叶总黄酮积累量影响的机制,分析桑叶经霜前后总黄酮积累量合成关键酶苯丙氨酸解氨酶(phenylalnine ammonialyase,PAL)活力的动态变化,并对总黄酮积累量及气候温度进行相关性分析。在6 m L pH 8.8、0.1 mol/L硼砂-盐酸缓...为研究经霜对桑叶总黄酮积累量影响的机制,分析桑叶经霜前后总黄酮积累量合成关键酶苯丙氨酸解氨酶(phenylalnine ammonialyase,PAL)活力的动态变化,并对总黄酮积累量及气候温度进行相关性分析。在6 m L pH 8.8、0.1 mol/L硼砂-盐酸缓冲液中加入0.2 g桑叶叶片、0.2 g聚乙烯吡咯烷酮,底物L-苯丙氨酸浓度为0.04 mol/L,40℃条件下水浴反应40 min后测定经霜前后桑叶PAL活力,采用紫外分光光度法测定经霜前后桑叶总黄酮积累量。结果表明:PAL活力与平均气温呈极显著负相关,与总黄酮积累量呈极显著正相关,较低的温度有利于黄酮类物质的积累。展开更多
基金Islamic Development Bank for the financial support with a master degree scholarship
文摘Objective:To assess antioxidant activities of different parts of Euphorbia hirta（E.hirta）,and to search for new sources of safe and inexpensive antioxidants.Methods:Samples of leaves,stems, flowers and roots from E.hirta were tested for total phenolic content,and flavonoids content and in vitro antioxidant activity by diphenyl-1-picrylhydrazyl（DPPH） assay and reducing power was measured using cyanoferrate method.Results:The leaves extract exhibited a maximum DPPH scavenging activity of（72.96±0.78）%followed by the flowers,roots and stems whose scavenging activities were（52.45±0.66）%,（48.59±0.97）%,and（44.42±0.94）%,respectively.The standard butylated hydroxytoluene（BHT） was（75.13±0.75）%.The IC<sub>50</sub>,for leaves,flowers,roots,stems and BHT were 0.803,0.972,0.989,1.358 and 0.794 mg/mL,respectively.The reducing power of the leaves extract was comparable with that of ascorbic acid and found to be dose dependent. Leaves extract had the highest total phenolic content[（206.17±1.95） mg GAE/g],followed by flowers,roots and stems extracts which were（117.08±3.10） mg GAE/g,（83.15±1.19） mg GAE/g,and （65.70±1.72） mg GAE/g,respectively.On the other hand,total flavonoids content also from leave had the highest value[（37.970±0.003） mg CEQ/g],followed by flowers,roots and stems extracts which were（35.200±0.002） mg CEQ/g,（24.350±0.006） mg CEQ/g,and（24.120±0.004） mg CEQ/ g,respectively.HPTLC bioautography analysis of phenolic and antioxidant substance revealed phenolic compounds.Phytochemical screening of E.hirta leaf extract revealed the presence of reducing sugars,terpenoids,alkaloids,steroids,tannins,flavanoids and phenolic compounds. Conclusions:These results suggeste that E.hirta have strong antioxidant potential.Further study is necessary for isolation and characterization of the active antioxidant agents,which can be used to treat various oxidative stress-related diseases.
