ISOLATION AND BIOACTIVITIES OF SECONDARY METABOLITES FROM ENDOPHYTIC FUNGAL STRAINS ISOLATED FROM ROOT SAMPLES OF Persea americana (MILL.)
CHIAMAKA FELICITAS OKPALANWA1, JUSTINE ONYECHISOKA OZOMMA1,*, UKAMAKA FAITH OSUJI1, DINEBARI PHILIP BEREBON1, CHIJIOKE EMMANUEL EZEOBIORA2, STEPHEN CHIJIOKE EMENCHETA1,3,*, EBELE BENEDETTE ONUIGBO1, ANTHONY AMAECHI ATTAMA4
1. Department of Pharmaceutical Microbiology and Biotechnology, University of Nigeria, Nsukka, 410001, Nigeria.
2. Department of Pharmaceutical Microbiology and Biotechnology, University of Lagos, Nigeria
3. Division of Microbiology and Infection, University of Leicester, LE1 7RH, Leicester, United Kingdom.
4. Department of Microbiology, University of Nigeria, Nsukka, 410001, Nigeria
Afr. J Pharm Res Dev; Volume 18(1): . 626-641 ; 2026
ABSTRACT
The demand for the synthesis of innovative bioactive agents has been driven by rising rates of antibiotic resistance. Persea americana (Mill.) is a plant traditionally implicated for its therapeutic effects. This study aimed to isolate endophytic fungi from the roots of P. americana, extract secondary metabolites, and investigate their biological activities. Three (3) endophytic fungi (R12, R22P, R33P) were isolated from the plant root using standard protocols. Using the discontinuous batch method with a combined cooked rice and potato dextrose broth, the fungal isolates were employed in a fermentation system, and secondary metabolites were extracted with ethyl acetate. The antimicrobial activities of the metabolites against Escherichia coli, Klebsiella pneumonia, Bacillus subtilis, Serratia marcescens, Sarcina lutea, Staphylococcus aureus, Pseudomonas aeruginosa, Candida albicans, R12, R22P, and R33P fungi isolates using the agar-well diffusion method. In vivo, acute-inflammatory and toxicological assays were done using standard procedures. Against the bacteria, the antimicrobial effects of metabolites were highest against B. subtilis and E. coli (IZD = 9 mm), while S. lutea had the least across the metabolites (IZD = 0 mm). For fungi, the highest activity was recorded against R33P (IZD = 9 mm), while C. albicans have the least (IZD = 4 mm). The secondary metabolite of R12 had the best antibacterial activity, followed by R33P, then R22P, while R22P had the best antifungal activity, followed by R33P, then R12. In the in vivo acute inflammatory assay, the fungi metabolites generally showed an increase in inflammation from 0 minutes to 2 hours and a slight decrease from 3 to 4 hours. The toxicity assay carried out shows that the fungi metabolites are less toxic. The study highlights the importance of understanding endophytic fungi and presents room for improvement.
Keywords:Persea americana, Endophytic fungi, Secondary metabolites, Antimicrobial activity, Anti-inflammatory activity, Toxicological evaluation
Email of correspondence: stephen.emencheta@unn.edu.ng;
https://doi.org/10.59493/ajopred/2026.1.23 ISSN: 0794-800X (print); 1596-2431 (online)