Antimicrobial characteristics of endophytic Aspergillus terreus and acute oral toxicity analysis

Background: Endophytic fungi produce biologically robust metabolites suitable for diverse applications, which support the increasing exploration of these fungi. The study aimed to investigate the in vitro antimicrobial properties of the metabolites of endophytic fungus Aspergillus terreus which isolated from the leaves of Psidium guajava plants while the acute oral toxicity was assessed in vivo. Results: A. terreus (OR125572) was successfully isolated for the first time from P. guajava. . The ethyl acetate extract of A. terreus exhibited antibactericidal effects against Enterobacter aerogenes with a minimum inhibitory concentration of 18.75 mg/ml in contrast to 75.00 +/- 0.0, 37.50, and 37.50 mg/ml, respectively against Staphylococcus aureus, Escherichia coli, and Bacillus sphaericus were 75.00 +/- 0.0, 37.50, and 37.50 mg/ml, respectively. Analysis of the crude extract obtained from A. terreus by GC-MS revealed a total of 32 distinct compounds. The major components included 1,2-benzenedicarboxylic acid, di-isooctyl ester; hexyl oxecan-2-one and phenol. The acute oral toxicity study found no symptoms of toxicity and no mortality until the 14th d, suggesting that the LD50 50 value of A. terreus extract might exceed 1 ml/kg. The group receiving 0.5 ml/kg of A. terreus extract experienced a 42.9% increase in body weight, while administration of varying dosages resulted in a significant reduction in MCV levels. There was also a significant increase in the proportion of monocytes across all treated groups. Conclusions: The study demonstrated the potential of A. terreus as a source of antimicrobial and other bioactive compounds, with relatively low acute toxicity. How to cite: Shehabeldine AM, Abdelaziz AM, Abdel-Maksoud MA, et al. Antimicrobial characteristics of endophytic Aspergillus terreus and acute oral toxicity analysis. Electron J Biotechnol 2024;72. https://doi. org/10.1016/j.ejbt.2024.07.003. (c) 2024 The Authors. Published by Elsevier Inc. on behalf of Pontificia Universidad Cat & oacute;lica de Valparaiso. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-ncnd/4.0/).