Estudo químico e atividades biológicas dos extratos do fungo actinomucor elegans accc18.1a endofítico de rhizophora mangle l. (rhizophoraceae)

Abstract

The study of underexplored natural sources, especially in the Amazon region, has gained significance in recent years. Considering the Amazon as the largest forest in the world, it is notable that many species still remain undiscovered. In this context, research on secondary metabolites of endophytic fungi has sparked growing interest in the scientific community, driven by the potential these microorganisms hold in the field of health. Microorganisms have been a rich source of bioactive metabolites with various applications such as agrochemicals, antibiotics, immunosuppressants, antiparasitic, and anticancer agents. The aim of this study was to contribute to the investigation of endophytic fungi in mangrove plants of the Brazilian Amazon through the isolation and identification of compounds with antimicrobial, allelopathic, and anticancer activities from the fungus Actinomucor elegans AcCC181A, which was isolated as an endophyte from the plant Rhizophora mangle L. (Rhizophoraceae). Using chromatography techniques, the phenolic compounds tyrosol (S-1), 4-hydroxyphenylacetic acid (S-2), 4-formylphenyl 2-phenylacetate (S-3), and phenylacetic acid (S-4) were isolated. From tyrosol, the substances 4-(2-acetoxyethyl)-phenylacetate (S-5), 4-(2-(butyryloxy)ethyl)- phenylbutyrate (S-6), and 4-(2-(benzoyloxy)ethyl)phenylbenzoate (S-7) were obtained through structural derivatization. The structures of the substances were elucidated using Nuclear Magnetic Resonance (NMR) and Mass Spectrometry (MS) techniques. The substances and crude extract were tested against the bacteria E. coli, Bacillus subtilis, S. typhimurium, S. aureus, and Xanthomonas axonopodis pv. passiflorae, showing antimicrobial activity results. Cytotoxicity and cell viability assays of the isolated substances S-1, S-2, and S-3 were also performed. All tested substances demonstrated potential cytotoxic activity on gastric cancer cell lines. Additionally, the allelopathic potential of the crude extract was evaluated, showing activity with lettuce seeds. It is important to note that compounds S-6, S-3, and S-7 are being tested for the first time in antimicrobial assays. Furthermore, it is relevant to emphasize that this study represents the first report of antimicrobial assays conducted with the substances isolated in this work against the bacteria Xanthomonas axonopodis pv. passiflorae.