The endophytic Aspergillus strains: A bountiful source of natural products

Abstract

Fungi that invade plant inner tissues without inducing disease symptoms are known as fungal endophytes. They represent a promising and tremendous reservoir of natural products with valuable biological potentials for application in medicine, agriculture and industry. Among the numerous existing endophytic fungi, Aspergillus strains constitute one of the most prolific sources of secondary metabolites with diverse chemical classes and interesting biological activities. This review covers the literature of the year 2020, reporting the isolation of 202 compounds obtained from more than 10 different endophytic Aspergillus species associated with different host plants. Analysis and interpretation of the collected data revealed that chemical investigation of endophytes belonging to the genus Aspergillus may greatly contribute to the discovery of potential drug leads. The isolated metabolites were chemically various and exhibited diverse biological activities such as antibacterial, anti‐cancer, anti‐plasmodial, anti‐inflammatory, antioxidant, immunosuppressive and antifungal activities. Moreover, adoption of advanced technology in molecular biology together with modern chemical tools is anticipated to improve the discovery of new biopharmaceuticals from this valuable microbial world in the future.

A New Unsaturated Aliphatic Anhydride from Aspergillus candidus T1219W1, an Endophytic Fungus, from Pittosporum mannii Hook f.

“…Aspergillus candidus, an endophyte, was isolated from the leaves of Pittosporum mannii and cultured with PDA and unpolished rice. Successive normal phase column chromatography used to fractionate and purify the ethyl acetate crude extract of A. candidus led to the isolation of eleven compounds (1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11), among which an unparalleled unsaturated aliphatic anhydride derivative (Z)-(12Z)-heptadec-12-enoic-2′-hydroxypropanoic anhydride (1) as well as ten known compounds (2-11) (Figure 1). Compound (1) was obtained as a dextrorotatory ([a] 24 D � +0.89 (c 0.01; MeOH)) white amorphous powder.…”

“…Figure S16-S17: 1 H-NMR and HMBC spectra of 5,4"-dihydroxy-7,8-dimethoxyfavone (4). Figure S18-S19: 1 H-NMR and 13 C-NMR spectra of 3hydroxyterphenyllin (6). Figure S20-S21: 1 H-NMR and 13 C-NMR spectra of 1,4-dimethoxy-2,4,"4″-trihydroxy-pterphenyllin (5).…”

“…Fungal endophytes show a wide diversity and host specifcity [3,4]. Te endophytic fungal genus Aspergillus is a signifcant reservoir of promising biologically active chemical leads including butenolides, alkaloids, terpenoids, cytochalasins, phenalenones, p-terphenyls, xanthones, sterols, diphenyl ether, and anthraquinone derivatives and consequently diverse biological activities [5,6]. Aspergillus candidus had been shown to be rich in favonoid secondary metabolites [7] amongst which are antibiotic chlorfavonin [8] and cytotoxic terphenyls [9,10].…”

Metabolites of medicine food homology-derived endophytic fungi and their activities

“…Eurotiales mainly includes Aspergillus and Penicillium , which may produce terpenoids, polyketides, polysaccharides, esters, phenols, and organic acids. Endophytes of Aspergillus ( El-hawary et al, 2020 ; Hagag et al, 2022 ), Penicillium ( Marie et al, 2020 ), Fusarium ( Manoj and Anil, 2016 ; Marie and Toghueo, 2019 ), Drechmeria ( Liang et al, 2018 ; Yu et al, 2018 ; Zhao, J. et al, 2018b ), and Trichoderma ( Patel, J. et al, 2019 ) possess significant antibacterial, antifungal, antioxidant, anti-inflammatory, and anticancer activities.…”

Anti-Tobacco Mosaic Virus Indole Alkaloids from the Nicotiana tabacum-Derived Fungus Aspergillus versicolor

“…Endophytic fungi represent a promising and huge natural product pool with valuable biological potential for applications in medicine, agriculture, and industry . Among the numerous existing endophytic fungi, Aspergillus strains constitute one of the most prolific sources of secondary metabolites (SMs) with diverse chemical classes and interesting biological activities. , Whole genome sequencing has revealed that Aspergillus strains have the capacity to produce a far greater number of SMs than those that have been isolated. − Prenylated indole alkaloids as hybrid natural products, derived from prenyl diphosphates and tryptophan or its precursors, have attracted widespread attention from chemists and biologists due to their diverse chemical structures and biological activities. , Among them, the fungal neurotoxin α-cyclopiazonic acid ( α -CPA), a nanomolar inhibitor of Ca 2+ -ATPase, has a pentacyclic indole tetramic acid scaffold and was first isolated from Penicillium cyclopium followed by many Penicillium and Aspergillus strains . In addition, a large number of CPA variations have been isolated in nature, involving indole or oxindole alkaloids of the tetramic acid unit, with attractive biological activities such as anti-TMV activity, , cytotoxicity, , antioxidant activity, , antibacterial activity, and other activity .…”