Antimicrobial Activity and Phytochemical Screening of Sarcocolla Gum Resin

Background and objective: Searching for a new antimicrobial agent is a significant challenge because of increasing resistance of microbes to antibiotics. Because plants are an inexpensive source of rich metabolic substances that are highly efficient, this study was designed to evaluate the antimicrobial activity of Sarcocolla gum resin extracted from Astragalus sarcocolla root and its phytochemicals. To the best of the author's knowledge, the antimicrobial activity of Sarcocolla gum resin has not previously been reported.

Materials and methods: The antimicrobial activity of Sarcocolla gum resin was evaluated using a well diffusion assay. The effect of water and ethanol extracts in various concentrations (20, 40 and 60%) against the growth of pathogenic bacteria and yeast were tested.

Results: The results showed that the lower concentration (20%) of water and ethanol extracts had no inhibitory effect on any of the tested microbes except Staphylococcus aureus (S. aureus) ATCC 29213. However, an antimicrobial effect of water and ethanol extracts was observed on most tested microbes at higher concentrations (40 and 60%). The S. aureus ATCC 29213 was resistant to all ethanol extract concentrations. In contrast, S. aureus ATCC 29213 was inhibited by water extracts at all concentrations tested. Minimum inhibitory concentrations (MIC) were estimated using a 2-fold dilution method and MIC values were between 12.5-25 μg mL-1. Phytochemical screening was performed using standard procedures that showed the presence of sterols, terpenoids, flavonoids, alkaloids, saponins and tannins.

Conclusion: This study showed that Sarcocolla gum resin extract possesses high antimicrobial activity that depends on the solvent type, the concentration of plant extract and the microbe type. These results provide a new source of antimicrobial that may be useful in the manufacture of antibiotics.