以高通量方法筛选红桑叶的抗菌活性并进行活性组分的分离研究

目的通过一种简单快速的高通量方法筛选具有抗菌活性的植物提取物,并通过此种方法从有活性的粗提物中纯化活性组分。方法首先建立植物提取物库和抗菌的高通量筛选方法。然后针对转糖链球菌Streptococcus mutans和伴放线放线杆菌Actinobacillus actinomycetemcomitans进行高通量筛选。结果通过筛选发现红桑叶具有很强的抑菌活性。为了进一步研究其活性,将其粗提物通过HPLC进行分离得到71个组分,再通过同样的高通量筛选方法进行抗菌活性测定,对有活性的组分通过血琼脂法进行验证。实验数据表明红桑叶的一个组分#31对两种细菌有几乎完全的抑制(抑制率>99%),而另外两个组分对伴放线放线杆菌Actinobacillus actinomycetemcomitans有部分抑制。结论所建立的高通量筛选方法简便快捷,筛选结果稳定可靠,可用于大规模的植物提取物的抗菌活性筛选。红桑叶具有很强的抗菌活性,且可分离得到活性组分,红桑叶具有进一步开发为抗菌药物和保健品的潜力。

Identification of the Antibacterial Activity ofMorus rubra Leaves by a High- Throughput Screening Method

Objective This research intended to test the antibacterial activity of a plant extract library using a simple and fast colorimetric detection method and identify those plant extracts with bioactivity,and to further purify those bioactive fractions of the selected plant extracts.Methods We first created a plant extract library and developed an antimicrobial High Throughput Screening(HTS) method.Then,the plant extracts were tested for antibacterial activity against two species of bacteria,S.mutans and A.actinomycestemcomitans.Results The Morus rubra leaf extract was selected because it had the strongest biological activity against the oral bacteria tested.To further study the Morus rubra leaves,the extract was separated into small fractions via high-performance liquid chromatography(HPLC).The fractions were tested against bacteria S.mutans and A.actinomycestemcomitans using HTS and the antibacterial activity of those selected bioactive fractions was further confirmed by blood agar plating method.One fraction of Morus rubra leaves,#31,exhibited near complete inhibiton(99% or better) for both bacteria,while two other fractions exhibited some,but not complete,inhibition of A. actinomycestemcomitans.Conclusion The HTS can be used to screen for a large plant extract library due to its fast and simple procedure.Morus rubra leaves exhibited the strongest antibacterial activity and the active fraction was obtained.The Morus rubra leaves have potential usage to treat bacterial infection in the future.