Purpose:
The purpose of the study is to evaluate the antimicrobial and antitumor activities of
Stevia rebaudiana
(Asteraceae) leaf extracts.
Methods:
Four solvent extracts (ethyl acetate, acetone, chloroform and water) of
Stevia rebaudiana leaves were investigated against
Staphylococcus aureus
,
Salmonella typhi
,
Escherichia coli
,
Bacillus subtilis
,
Aeromonas hydrophila
and
Vibrio cholerae
by using agar well diffusion method.
Candida albicans
,
Cryptococcus neoformans
,
Trichophyton mentagrophytes
and
Epidermophyton
species were used to test anti-yeast and antifungal activity. The cytotoxic effects of the extracts on Vero and HEp2 cells were assayed using 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide [MTT].
Results:
Among the four extracts tested, acetone extract had effective antibacterial potential, followed by ethyl acetate extract. The acetone extract showed greater activity against Gram-positive than against Gram-negative organisms. All the extracts were active against
Epidermophyton species and
Candida albicans . The 1:8 dilution of the acetone extract was non-toxic to normal cells and also had both anticancer and anti-proliferative activities against cancerous cells.
Conclusion:
The study confirms the antimicrobial and antitumor activities of
Stevia rebaudiana leaves extracted using various solvents, and is therefore, a potential drug that requires further studies and development.
