Antibacterial And Antimosquito Active Research About Eclipta Prostrata L Extracts And ItsExtraction Method

With the rapid development of the global economy, more and more people seek to have a healthy and green life. As a result, the medical pattern has been changed, more and more people are paying attention to natural medicines. Eclipta as a kind of traditional Chinese medicine has been wildly applied in ealthcare due to its immunoregulation, hemostasis, protective effects for liver, antibacterial activity and anti-mosquito characteristics. However, this filed lacks a sufficient survey and research about the active ingredients in Eclipta, which limits further medical development and utilization of Eclipta.To address this issue, the extraction technology of active ingredients of Eclipta has been studied in this paper firstly. For comparison, two methods including solvent extraction and ultrasound assisted extraction of the solvent extraction have been adopted to extract the active ingredients from herb of Eclipta. The analysis of the experimental results has shown that the extracted ingredients are not able to have an anticipated and satisfying antibacterial Property.Then,simultaneous distillation extraction has been adopted to extract the active ingredients from herb of Eclipta, respectively. It has been shown that the ingredients extracted from the herb of Eclipta via simultaneous distillation extraction can achieve the best effect in antibacterial activity. As a result, the simultaneous distillation extraction method on the herb of Ecliptahas been determined to extract the active ingredients in our study.It is necessary to analyze the active ingredients. Based on GC-MS equipment, Peak area normalization method was used to estimate the portion of various components in Eclipta. A total of 24 kinds of main active components are elected, including acids, erucamid, thiophenes, esters, alkanes, ketones, aldehydes and more.Finally, the retention indices of some active ingredients have been calculated as the foundation for the following studies.Antibacterial activity about Eclipta based on 14 kinds of representative gram strains.these strains have been selected as testing strains to test for their proclaimed antibacterial. The results haven shown that the not concentration extraction from Eclipta has a poor antibacterial effects, which even has no antibacterial effects for some bacterial strains. However, after concentration, the antibacterial performance improved significantly. And the minimal range needed to have an effect is 160-1280μg/mL. It has been demonstrated that the extraction has an optimal antibacterial performance.At the end of this paper, the effect of Eclipta essential oil of mosquito repellent has been investigated. Hoping to develop a new kind of natural mosquito repellent drugs. The experiments were conducted in two aspects including mosquito killing test and mosquito avoidance test. The results of the mosquito killing test have shown that the active ingredients extracted from Eclipta are more effective to kill mosquito larva with a small dense of 128 μg/mL.25%(wt) Eclipta samples based on active ingredients are still effective for adult mosquitoes with an eradicative rate of 92.60%, which shows its robust and effects for mosquito control and expellant.As a summary, this thesis focuses on the extraction of active ingredients and their application and proposes a framework about extraction, identification and application of active ingredients in Eclipta. It is believed that the thesis sheds light on the development and fundamental research behind Chinese herbal medicines and contributes to the development of new medicines.