Affiliation:
1. Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, King Khalid University, Abha, Saudi Arabia
Abstract
Abstract
Background:
Since the past decade, there has been a significant rise in invasive infections by Trichosporon and nonneoformans cryptococcus species, especially in immunocompromised patients having hematological malignancies. These infections, usually associated with the use of indwelling devices, are difficult to cure because of the resistance to standard antifungal agents and the formation of biofilms on indwelling devices. The long-term use of antimicrobials adds to the severity of the disease.
Objective:
The objective of this study was to investigate the antifungal and antibiofilm properties of ethanolic leaf extract of Myrtus communis against Trichosporon mucoides and Cryptococcus humicola and evaluate the impact of the extract on the efficacy of the common antifungal medications such as fluconazole and nystatin.
Materials and Methods:
Agar well diffusion method and microplate dilution methods were used to determine the zone of inhibition and minimum inhibitory concentrations (MIC). Crystal violet and microplate alamarBlue methods were used to investigate the biofilm formation and growth kinetics of the fungi. A checkboard assay was used to determine the combined effect of M. communis extract and standard antifungal agents against these fungal strains.
Results:
The M. communis leaf extract inhibited the planktonic and biofilm growth of both the fungal strains T. mucoides and C. humicola with MIC of 78 μg/ml and MFIC of 19.5 μg/ml. The zone of inhibition for T. mucoides and C. humicola was found to be 22 mm and 23 mm, respectively. The growth inhibition in both the strains was dose dependent, with more growth inhibition at 2 × MIC than at MIC. The extract showed synergistic activity in association with fluconazole, while in association with nystatin its activity was indifferent for both the strains tested.
Conclusion:
The bioactives of ethanolic M. communis leaf extract possess a strong antifungal activity and could inhibit the growth of fungal cells entrenched in biofilm matrix. Purification and evaluation of compounds for antifungal activity need to be explored.