Screening open source traditional Chinese medicine extracts for growth-inhibiting properties towards Acinetobacter baumannii

Infections caused by Acinetobacter baumannii and other pathogenic bacteria are a worldwide concern due to their increasingly prevalent multidrug resistance. World leaders and health organizations across the globe have voiced their concerns over antibiotic resistance and the critical need for the development of novel antibiotics. Although the number of new antibiotic drugs entering the marketplace in recent years has been limited, it is encouraging to note that there are many initiatives in academia, industry, and government focused on this issue. This study outlines the investigation of a publicly available library of Traditional Chinese Medicine extracts to discover new compounds that could potentially inhibit the growth of a multidrug-resistant A. baumannii strain. Within this library of over 600 natural product samples, two individual extracts were found which exhibited over 50% mean growth inhibition of this bacterial strain at an extract concentration of 10 µg/mL. Fractionation of these two extracts into more isolated compounds also resulted in inhibitory activity. The results of this study highlight the value of this natural products library as a resource for further investigation in discovering anti-infective agents, especially during this global crisis of antibiotic resistance.  Key words: Traditional Chinese Medicine, Acinetobacter baumannii, growth inhibition, antibiotic resistance.