In silico PASS analysis and determination of antimycobacterial, antifungal, and antioxidant efficacies of maslinic acid in an extract rich in pentacyclic triterpenoids

Objective/background: Microbial infections such as tuberculosis is a major cause of mortality worldwide. Plant-derived phytochemicals have a long history of providing much-needed novel therapeutics. Triterpenoids are among the prominent phytochemicals that possess numerous biological activities. Among them is maslinic acid (MA), a biologically active olean-type pentacyclic triterpenoid. In search of a novel antimicrobial agent, we aimed to evaluate the antimicrobial potential of MA. Methods: Antibacterial and antifungal activity was evaluated through the agar well diffusion method. Antitubercular activity was analysed through the agar well diffusion and disc diffusion methods, respectively. Antioxidant capacity was determined through assays for total antioxidant capacity, 2,2-diphenyl-1-picrylhydrazyl radical scavenging, hydrogen peroxide radical scavenging, and Fe3+ reducing power. The program Prediction of Activity Spectra for Substances was used to calculate the possible biological activity of MA. Results: MA showed dose-dependent antioxidant activity similar to that of ascorbic acid. It had no inhibitory effect on bacterial strains, but it had moderate activity against the fungi Aspergillus flavus and Ustilago maydis, with Aspergillus niger being the most sensitive to MA. MA also exhibited strong antimycobacterial activity. Probable antioxidant, antibacterial, and antifungal activity of MA based on software calculations are 0.479, 0.363 and 0.589 respectively. Conclusion: This work provides scientific evidence of the antioxidant, antifungal, and antimycobacterial activities of MA, showing its potential application in the development of natural antioxidants and antimicrobial agents for the agro-food and pharmaceutical industries. (C) 2016 Asian-African Society for Mycobacteriology. Production and hosting by Elsevier Ltd.