Recent developments and future prospects of antimicrobial metabolites produced by endophytes

Endophytes, found ubiquitous in all plant species in the world, contribute to their host plants by producing plenty of substances that provide protection and ultimately survival value to the plant. Many researches have proven that endophyte is a new and potential source of novel natural products for exploitation in modern medicine, agriculture and industry. So far, a great number of novel natural products possessing antimicrobial activities have been isolated from endophytes. It is believed that screening for antimicrobial compounds from endophytes is a promising way to overcome the increasing threat of drug resistant strains of human and plant pathogen. Antimicrobial metabolites isolated from endophytes belong to diverse structural classes, including: alkaloids, peptides, steroids, terpenoids, phenols, quinones, and flavonoids. In this review, many well-studied areas are presented and examples will be given to discuss the structure of compounds isolated from endophytes extracts with antimicrobial activities and show the wide variety of approaches taken within the field. These achievements would provide the opportunity to utilize endophytes as a new source for production of antibiotics.