Antimicrobial Potential of Endophytic Fungi From Artemisia argyi and Bioactive Metabolites From Diaporthe sp. AC1

Abstract

Endophytic fungi of medicinal plants are important sources of active natural products. In this study, 26 fungi were isolated from Artemisia argyi, which were belonging to eight genera, namely, Alternaria, Fusarium, Chaetomium, Phoma, Diaporthe, Trichoderma, Gibberella, and Colletotrichum. The antimicrobial activities of all fungal extracts were tested by using the cup-plate method against Staphylococcus aureus, Salmonella enteritidis, and Fusarium graminearum. The results demonstrated that 25 extracts (96%) exhibited inhibitory activity against at least one of the tested pathogenic microorganisms. The strain Diaporthe sp. AC1, which showed good antimicrobial activity and high yield of crude extract from fermentation, was selected for the study of secondary metabolites. The crude extract of strain AC1 was purified by silica gel column chromatography, Sephadex LH-20 gel column chromatography, and HPLC, and finally, a new compound phomopsolide G (1), together with three known phomopsolides (2–4) and four other known compounds (5–8), was obtained. The structures of the compounds were elucidated by NMR and/or HR-MS spectroscopy. Microdilution method and MTT colorimetry were used to determine the bioactivity of the compounds. The study demonstrated that the new compound 1 had moderate antifungal activity against F. graminearum, Fusarium moniliforme, and Botrytis cinerea and weak antibacterial activity against Staphylococcus aureus. Compound 1 also showed weak cytotoxicity against HepG2, A549, and MDA-MB-231, with IC50 values of 89.91, 107.65, and 53.97 μM. Additionally, other compounds also exhibited antimicrobial and/or cytotoxic activities. The findings provided the basis for searching drug and agricultural lead compounds from A. argyi-associated fungi resources.

Antibacterial and Antioxidant Activity of Endophytic Fungi Extract Isolated from Leaves of Sungkai (Peronema canescens)

“…It has proven that 6-pentyl-𝛼-pyron, which is produced by T. harzianum and T. hamatum, efficiently has antioxidant and antibacterial properties against Acidovorax avenae, Erutimcarafavora, and Xanthomonas campestris (Al Rajhi et al, 2022;Baazeem et al, 2021). T. asperellum is also known to contain compounds such as alkaloids, tannins, phenolics, triterpenoids, and flavonoids which effectively have bioactivity, such as antipyretic, antibacterial, anticancer, and antioxidant (Gu et al, 2022;Karuppiah et al, 2019;Scudeletti et al, 2021;Singh et al, 2021). Secondary metabolites from endophytic fungi can be used as relevant sources of raw materials for new medicine.…”

Pioneering Metabolomic Studies on Diaporthe eres Species Complex from Fruit Trees in the South-Eastern Poland

“…Moreover, phomopsolide A/C ( 62 ), from the endophytic Diaporthe sp. AC1 from Artemisia argyi , was proved to inhibit the growth of Fusarium graminearum , F. moniliforme , Botrytis cinerea , and Verticillium dahliae , indicating that the compound may have a broad spectrum of antifungal activity [ 29 ].…”

“…Over the past decade, 335 bioactive secondary metabolites have been obtained from known Diaporthe species and from those for which only a generic name has been assigned. [ 25 , 27 , 28 ] Among bioactive compounds 246 were isolated from Phomopsis , 106 from Diaporthe , and 17 from both species [ 25 , 29 ]. The metabolites produced by this genus include terpenoids, steroids, macrolides, ten-membered lactones, alkaloids, flavonoids, fatty acids, and polyketides, being the main structural type [ 25 ].…”

Antimicrobial and Cytotoxic Activity of Endophytic Fungi from Lagopsis supina

“…Four pathogenic bacteria, including Staphylococcus aureus (ATCC25923), Listeria monocytogenes (CGMCC1.10753), Escherichia coli (ATCC 8739), and Salmonella enteritidis (ATCC13076) were purchased from the Shanghai Bioresource Collection Center (SHBCC). Seven pathogenic fungi, including Fusarium graminearum , F. oxysporum , F. moniliforme , F. stratum , Botrytis cinerea , Magnaporthe oryzae , and Verticillium dahliae , were all separated and identified by our laboratory [ 15 , 16 ].…”