Understanding the antimicrobial properties of natural plant extracts and herbal infusions

草药，茶和天然产品长期以来一直用于中国和印度的传统药物，并越来越受欢迎的自我护理，并用于现代临床实践。2018年NICE和PHE咳嗽指南指出，抗生素不应作为一线治疗药物，建议使用蜂蜜和几种草药（如天竺葵）。需要考虑对复杂的多微生物群落（例如生物膜）的有效性，已知这些群落是大多数慢性感染的原因。试点数据还显示，一种绿色茶基输液（山茶）和一种姜黄输液（姜黄）在针对冠状病毒进行测试时显示出抗病毒活性。许多其他草药和天然产品都具有已报道的抗菌活性，但通常基于单一物种研究，并不能反映现实情况。基于NBIC资助的试点研究的初步数据，该项目旨在使用标准和先进的方法系统地测试一系列草药和植物提取物以及输液。使用一系列通常与上呼吸道感染相关的细菌和病毒病原体，包括产热链球菌、铜绿假单胞菌、流感嗜血杆菌、卡他莫拉菌、冠状病毒、RSV和流感，我们将测试现有的和开发新的用于测量抗菌活性的模型。这将包括了解作用机制。目的：使用MBEC和MBIC试验评估一系列浸提液对几种关键细菌病原体的生物膜活性。开发一种细胞培养试验，以便对上呼吸道细胞系上的关键病毒病原体进行研究，从而检测浸提液的抗病毒活性。确定与抗菌活性相关的浸提液之间的任何协同或拮抗关系。使用转录组学，蛋白质组学和先进的显微镜成像，以及跟踪可行的，但不可培养（VBNC）的人口和耐药谱的发展了解抗菌活性的机制。

Herbs, teas and natural products have long been used in traditional Chinese and Indian medicines and are becoming increasingly popular for selfcare, and for use in modern clinical practice. The 2018 NICE and PHE guidelines for coughs states that antibiotics should not be a first line treatment, and that honey and several herbs (such as Pelargonium) were recommended.There is a need to consider efficacy on complex polymicrobial communities (e.g. biofilms), which are known to be responsible for most chronic infections. Pilot data has also shown that a green tea-based infusion (Camellia sinsensis) and a turmeric infusion (Curcuma longa) demonstrates anti-viral activity when tested against coronavirus. Many other herbs and natural products have antimicrobial activity that has been reported but are often based on single species studies and do not reflect realistic conditions. Building on preliminary data from a NBIC-funded pilot study, this project aims to systematically test a range of herbal and plant extracts, and infusions, using standard and advanced methods. Using a range of bacterial and viral pathogens commonly associated with upper respiratory tract infections, including Streptococcus pyrogenes, Pseudomonas aeruginosa, Haemophilus influenzae, Moraxella catarrharis, coronavirus, RSV, and flu, we will test existing, and develop new, models for measuring antimicrobial activity. This will include understanding the mechanisms of action. Aims: Assessment of the antibiofilm activity of a range of extracts on several key bacterial pathogens using MBEC and MBIC assays. Develop a cell culture assay to allow investigation with key viral pathogens on upper respiratory tract cell lines to test the antiviral activity of extracts. Determine any synergistic or antagonistic relationships between extracts linked to antimicrobial activity. Understand the mechanisms of antimicrobial activity using transcriptomics, proteomics and advanced microscopy imaging, as well as tracking the development of viable but nonculturable (VBNC) populations and resistance profiles.