Untapped Potentials of Endophytic Fungi: A Review of Novel Bioactive Compounds with Biological Applications

Abstract

Over the last century, endophytic fungi have gained tremendous attention due to their ability to produce novel bioactive compounds exhibiting varied biological properties and are, therefore, utilized for medicinal, pharmaceutical, and agricultural applications. Endophytic fungi reside within the plant tissues without showing any disease symptoms, thus supporting the physiological and ecological attributes of the host plant. Ground breaking lead compounds, such as paclitaxel and penicillin, produced by endophytic fungi have paved the way for exploring novel bioactive compounds for commercial usage. Despite this, limited research has been conducted in this valuable and unique niche area. These bioactive compounds belong to various structural groups, including alkaloids, peptides, steroids, terpenoids, phenols, quinones, phenols, and flavonoids. The current review focuses on the significance of endophytic fungi in producing novel bioactive compounds possessing a variety of biological properties that include antibacterial, antiviral, antifungal, antiprotozoal, antiparasitic, antioxidant, immunosuppressant, and anticancer functions. Taking into consideration the portal of this publication, special emphasis is placed on the antimicrobial and antiviral activities of metabolites produced by endophytes against human pathogens. It also highlights the importance of utilization of these compounds as potential treatment agents for serious life-threatening infectious diseases. This is supported by the fact that several findings have indicated that these bioactive compounds may significantly contribute towards the fight against resistant human and plant pathogens, thus motivating the need enhance the search for new, more efficacious and cost-effective antimicrobial drugs.

Current State and Future Directions of Genetics and Genomics of Endophytic Fungi for Bioprospecting Efforts

“…A large number of potentially high-value bioactive compounds with pharmaceutical importance were discovered from cultivable endophytic fungi as reviewed by Manganyi and Ateba ( 2020 ). In this review we want to focus on the main strategies employed and the best practices to prevent experimental error in phenotyping endophytic fungi.…”

“…More than 100 years of research indicate that most, if not all of the billions of living land plants are host for different endophytic fungi in natural ecosystems. This makes this group of microorganisms one of the largest untapped natural resources for the bioprospecting of secondary metabolites and biosynthetic enzymes (Manganyi and Ateba, 2020 ).…”

“…for its proposed independent synthesis of taxol ( 1 ). Numerous studies have since then reported on the isolation of new and previously known secondary metabolites from endophytic fungi as recently reviewed by Manganyi and Ateba ( 2020 ) and Newman and Cragg ( 2020b ).…”

“…In this review we will first provide an overview of the phenotyping efforts of endophytic fungi including the best practices and a few interesting bioactive metabolites identified with each strategy. For a larger survey of bioactive secondary metabolites reported for endophytic fungi, we would like to refer to other recent reviews by Manganyi and Ateba ( 2020 ) and Newman and Cragg ( 2020a ). Second, genotyping strategies applied in endophytic fungi will be presented, followed by a brief overview of general strategies for hypothesis generation and experimental verification employed to establish a link between phenotype and genotype.…”

Screening of endophytic fungi from oil palm (Elaeis guineensis) in producing exopolysaccharides

“…Endophytic fungi have been considered as prominent bioresources of novel biomolecules and biologically active compounds in recent decades. Their capacity in producing secondary metabolites through fermentation with agricultural, biotechnological, industrial, and pharmaceutical prospects for downstream production and bio-economic development (Newman and Cragg 2015;Nisa et al 2015;Manganyi and Ateba 2020;Torres-Mendoza et al 2020). The first step in studying these fungi is through the isolation and identification of potential fungal strains which may be distinct for each host due to differentials in host species, sampling strategy and culture conditions (Zhang et al 2017).…”