Antimicrobial activity of emodin – secondary metabolites from Trichoderma against some human pathogenic bacteria in Wasit province, Iraq

Objective: To evaluate the antibacterial activity of emodin isolated from trichoderma longibrachiatum against certainpathogens in patients with bacterial disease.Methods: The cross-sectional study was conducted at Al-Zahraa Teaching Hospital, Wassit, Iraq, from December 2021to March 2022, and comprised tichoderma longibrachiatum taken from the Wasit University’s garden soil and weresubjected to plate morphology, microscopic examination, and polymerase chain reaction-internal transcribed spacertesting. Emodin was extracted by ethyl acetate with final yield of 58mg/L. Using the agar well diffusion method,emodin extract doses of 0.ug/ml, 1ug/ml, 2ug/ml and 4ug/ml were tested against clinical pathogenicmicroorganisms. Data was analysed using SPSS 22.Results: Emodin 0.5ug/ml showed high antibacterial activity against proteus mirabilis, with growth inhibition zoneof 8.7mm, followed by staphylococcus epidermidis 7mm, streptococcus pyogenes 7.6mm, staphylococcus aureus7.5mm, escherichia coli 6.7mm and klebsiella species 0.4mm. Pseudomonas aeruginosa was resistant to emodin0.5ug/ml.Conclusion: Emodin extract of trichoderma longibrachiatum showed high antimicrobial activity against humanpathogenic bacteria.5Keywords: Pseudomonas aeruginosa, Staphylococcus aureus, Proteus mirabilis, Escherichia coli, Trichoderma, Ethyl acetate,emodin, Agar, Mirabilis, Klebsiella, Bacterial, Polymerase.