In Vitro Anti-microbial Activity of Hydroethanolic Extracts of Ruellia tuberosa L. Eco-friendly Based-product Against Selected Pathogenic Bacteria

Search for new sources of antibacterial agents that are more environmentally-friendly to the environment and human health has emerged since synthetic antimicrobial drugs led to antibiotic resistance. South East Asia region is one of the world's most biodiverse regions and provide reservoir of new and potentially useful molecules from plants. Ruellia tuberosa L., an indigenous species from South East Asia, is a plant that is grown in almost in every area in Indonesia. In the current study, anti-microbial activity of hydroethanolic extracts of R. tuberosa L. was screened against S. aureus and E. coli, using well diffusion method. Results showed that hydroethanolic extracts of R. tuberosa L. at concentrations of 5; 10; 20, 50; 75; and 100% (v/v) resulted in inhibition zones of 7; 7; 9.80; 11.50; 14.15; and 15.25 mm, respectively, against S. aureus, Gram-positive bacteria. The inhibition zones against E. coli, Gram-negative bacteria, resulted in 7; 7; 7; 10.75; 11.00; and 15.00 mm, for concentrations of 5; 10; 20, 50; 75; and 100% (v/v), respectively. The commercial antibiotics, chloramphenicol and ampicillin were used for the control, and resulted in inhibition zones of 30.20 and 25.70 mm for S. aureus; 29.85 and 25.40 mm for E. coli. These results indicated that both extracts and antibiotics were more potent to inhibit S. aureus than E. coli. This study contributes to the development of environmentally friendly based-product for diseases caused by bacteria.