Endophytic fungi – an untapped source of potential antioxidants

Antioxidants are the substances that interact inside and outside of a biological system, against the damaging effects of highly reactive molecules called free radicals produced during metabolism. Among various natural alternative sources of bioactive metabolites, endophytic fungi have emerged as a significant reservoir of potent antioxidant compounds. These scantly explored micro-organisms are prolific producers of novel metabolites and have the capability to produce compounds that are exclusively isolated from Plantae. A wide array of compounds like nucleobases, polyketides, terpenoids, flavonoids, coumarins, xanthones, semiquinones, peptides, and phenolic acids have been identified as natural antioxidants. Some of these free radical scavengers have shown a wide application in the food and pharmaceutical industry as potential food preservatives, nutraceuticals, antibacterial, anticancer and antifungal agents. This review aims to highlight some of the novel compounds from endophytic fungi, discovered between the years 2013 – 2018 and their application as potential antioxidant candidates discussed through various biological assays.