雪松不同部位中原花青素的含量测定及其清除DPPH自由基的活性

Determination of proanthocyanidins and DPPH radical scavenging activity of different parts from Cedrus deodara

关键词:  雪松  原花青素  含量测定  紫外-可见分光光度法  DPPH自由基

Key words:  Cedrus deodara  proanthocyanidin  content determination  ultraviolet-visible spectrophotometer  DPPH free radical

摘要:

雪松(Cedrus deodara)是松科(Pianaceae)雪松属(Cedrus)树种的泛称,为广泛分布于喜马拉雅山脉的常绿树种,包括雪松(C. deodara)、黎巴嫩雪松(C. libani)、短叶雪松(C. brevifolia)和北非雪松(C. atlantica)等。雪松的针叶药用历史悠久,主要化学成分为黄酮类、苯丙素类、有机酸类、三萜类、甾体类、多糖及针叶胶等,具有抗肿瘤、抗氧化、改善记忆、抗菌及抗病毒等多种功效。为了测定雪松不同部位中原花青素的含量,并考察其清除DPPH自由基活性的能力,该研究以Fe³⁺ 离子为催化剂,用正丁醇-盐酸法分别测定雪松松针、花序、小枝、木质部、树皮中原花青素的含量,并对不同部位提取液清除DPPH自由基的能力进行测定。结果表明:松针、花序、木质部、树皮、小枝中原花青素的含量分别为12.93%、12.93%、6.41%、12.00%、3.37%,在质量浓度(以生药计)为0.8 mg·mL^-1时,其对DPPH自由基的清除率均达到或接近90%。该研究结果提示雪松各个部位的原花青素含量丰富,其提取液的体外抗氧化活性很高,这为雪松的进一步开发利用提供了很好的参考价值。

Abstract:

Cedrus deodara(Pinaceae family), which consists of C. deodara, C. libani, C. brevifolia and C. atlantica, is an evergreen tree growing extensively on the slopes of the Himalayas. Its leaves was a kind of chinese medicine for a long history. Its main chemical constituents include flavonoids, phenylpropanoids, organicacid,triterpenes,steroids,polysaccharides leaf glue and so on. The major pharmacological activities of pine needles of C. deodara include antitumor, antioxidation, improving memory, antibacterial and antivirus, ect. In order to determine proanthocyanidin content and DPPH radical scavenging activity of different parts from C. deodara. In this study, Fe³⁺ ion was used for catalysator, n-BuOH:HCl(95:5)was chromogenic agent and the detection wave-lengths were at 550 nm. And the content of proanthocyanidin was determined in different parts from C. deodara by ultraviolet-visible spectrophotometer. And antioxidant activity of extract from different parts of C. deodara were investigated by scavenging 1,1-Diphenyl-2-picrylhydrazyl free radical(DPPH). The results showed that proanthocyanidins content in different parts of C. deodara was pine needles(12.93%),inflorescence(12.93%),bark(12.00%), wood(6.41%), tender branchlets(3.37%). The extract from different parts of C. deodara had good antioxidant activity. In a certain concentration scope, there was a strong positive correlation between the scavenging activity and the concentrations. The order of IC₅₀ was tender branchlets > pine needles > wood> bark > inflorescence. Except for branchlets, their DPPH scavenging activities were around 90% while the concentration of the extract from different parts was 0.8 mg·mL^-1. The results indicated that there were higher proanthocyanidins content and antioxidant activities in different parts of C. deodara, which provide the reference on comprehensive development and utilization of C. deodara.