Phomotide A, a novel polyketide, from the endophytic fungus Phomopsis sp. CFS42

A Close View of the Production of Bioactive Fungal Metabolites Mediated by Chromatin Modifiers

Secondary metabolites produced by fungi are well known for their biological properties, which play important roles in medicine. These metabolites aid in managing infections and treating chronic illnesses, thereby contributing substantially to human health improvement. Despite this extensive knowledge, the vast biodiversity and biosynthetic potential of fungi is still largely unexplored, highlighting the need for further research in natural products. In this review, several secondary metabolites of fungal origin are described, emphasizing novel structures and skeletons. The detection and characterization of these metabolites have been significantly facilitated by advancements in analytical systems, particularly modern hyphenated liquid chromatography/mass spectrometry. These improvements have primarily enhanced sensitivity, resolution, and analysis flow velocity. Since the in vitro production of novel metabolites is often lower than the re-isolation of known metabolites, understanding chromatin-based alterations in fungal gene expression can elucidate potential pathways for discovering new metabolites. Several protocols for inducing metabolite production from different strains are discussed, demonstrating the need for uniformity in experimental procedures to achieve consistent biosynthetic activation.

Potential of Secondary Metabolites of Diaporthe Species Associated with Terrestrial and Marine Origins

Diaporthe species produce versatile secondary metabolites (SMs), including terpenoids, fatty acids, polyketides, steroids, and alkaloids. These structurally diverse SMs exhibit a wide range of biological activities, including cytotoxic, antifungal, antibacterial, antiviral, antioxidant, anti-inflammatory, and phytotoxic activities, which could be exploited in the medical, agricultural, and other modern industries. This review comprehensively covers the production and biological potencies of isolated natural products from the genus Diaporthe associated with terrestrial and marine origins. A total of 275 SMs have been summarized from terrestrial (153; 55%) and marine (110; 41%) origins during the last twelve years, and 12 (4%) compounds are common to both environments. All secondary metabolites are categorized predominantly on the basis of their bioactivities (cytotoxic, antibacterial, antifungal, and miscellaneous activity). Overall, 134 bioactive compounds were isolated from terrestrial (92; 55%) and marine (42; 34%) origins, but about half the compounds did not report any kind of activity. The antiSMASH results suggested that Diaporthe strains are capable of encoding a wide range of SMs and have tremendous biosynthetic potential for new SMs. This study will be useful for future research on drug discovery from terrestrial and marine natural products.

Acetylcholinesterase and butyrylcholinesterase inhibition by nectriapyrone and tryptophol isolated from endophytic fungus Phomopsis sp

Cholinesterase (ChE) inhibitors are currently the main drugs used to treat the cognitive symptoms of Alzheimer's disease (AD). Dual cholinesterase inhibitors, that is, compounds capable of inhibiting both acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE), are considered a new potential approach for the long-term treatment of patients with AD. We evaluated the ethyl acetate extract of Phomopsis sp., grown in liquid medium malt extract and potato dextrose (PDB), an endophyte isolated from the Brazilian medicinal plant Hancornia speciosa. The anticholinesterase (AChE) and butyrylcholinesterase (BuChE) activities were evaluated. The extracts exhibited dual action against AChE and BuChE. The compounds isolated from these extracts, nectriapyrone (1) and tryptophol (2), showed inhibitory action on BuChE (IC50 = 29.05 and 34.15 μM respectively), being selective towards BuChE. The discovery of selective BuChE inhibitors is extremely important for the development of drugs that can be used in the treatment of patients diagnosed with AD.

Z, Cubilla-Rios L. Structurally Uncommon Secondary Metabolites Derived from Endophytic Fungi

Among microorganisms, endophytic fungi are the least studied, but they have attracted attention due to their high biological diversity and ability to produce novel and bioactive secondary metabolites to protect their host plant against biotic and abiotic stress. These compounds belong to different structural classes, such as alkaloids, peptides, terpenoids, polyketides, and steroids, which could present significant biological activities that are useful for pharmacological or medical applications. Recent reviews on endophytic fungi have mainly focused on the production of novel bioactive compounds. Here, we focus on compounds produced by endophytic fungi, reported with uncommon bioactive structures, establishing the neighbor net and diversity of endophytic fungi. The review includes compounds published from January 2015 to December 2020 that were catalogued as unprecedented, rare, uncommon, or possessing novel structural skeletons from more than 39 different genera, with Aspergillus and Penicillium being the most mentioned. They were reported as displaying cytotoxic, antitumor, antimicrobial, antiviral, or anti-inflammatory activity. The solid culture, using rice as a carbon source, was the most common medium utilized in the fermentation process when this type of compound was isolated.

Potential of Endophytic Diaporthe sp. as a New Source of Bioactive Compounds

Endophytic fungi are symbiotically related to plants and spend most of their life cycle within them. In nature, they have a crucial role in plant micro-ecosystem. They are harnessed for their bioactive compounds to counter human health problems and diseases. Endophytic Diaporthe sp. is a widely distributed fungal genus that has garnered much interest within the scientific community. A substantial number of secondary metabolites have been detected from Diaporthe sp. inhabited in various plants. As such, this minireview highlights the potential of Diaporthe sp. as a rich source of bioactive compounds by emphasizing on their diverse chemical entities and potent biological properties. The bioactive compounds produced are of significant importance to act as new lead compounds for drug discovery and development.

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

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.

Hot off the Press

A personal selection of 32 recent papers is presented covering various aspects of current developments in bioorganic chemistry and novel natural products such as flavipeside A from Aspergillus flavipes.