Antimicrobial Potential of Miana Leaf Extract (Coleus scutellaroides(L) Benth) Against Salmonella typhi: In Vitro Study

Abstract

Introduction: Salmonella typhi is a bacilli gram-negative bacteria, belonging to the family Enterobacteriaceae, which causes typhoid fever. The high morbidity and mortality rates of typhoid fever and the problem of antibiotics resistance have encouraged development of the use of effective medicinal plants to treat typhoid fever. One of plant widely used as a medicinal plant is miana (Coleus scutellariodes (L.) Benth).Miana leaves contains flavonoid and tannin, in which flavonoid has antibacterial activity because it can denature and coagulate bacterial cell protein. Methods: Miana extracts were diluted in five concentration: 5%, 25%, 50%, 75% and 90%. Pure culture of S. typhi was identified by several biochemical test: TSIA, sulfide production, Indole, motility, vogesproskauer, methyl red and citrate. Inhibition test of extracts against bacteria using the Kirby-Bauer method with blank discs soaked in miana extract solutions, empirical antibiotics and negative control.  Results: Biochemical tests of S. typhi were TSIA: alkali/acid, sulfide production: positive, indole: negative, motility: positive, methyl red: positif, VogesProskauer: negative, and citrate: negative; they were suitable with characteristic of S. typhi. Miana extract inhibited the growth of S. typhi on concentrations of 5%, 25%, 50%, 75% and 90% with the mean inhibition zone diameter of 1.83 mm, 4.33 mm, 5.00 mm, 5.66 mm, and 6.00 mm, respectively and the average inhibition zone of empirical antibiotic levoflocaxin, chloramphenicol and amoxicillin were 24.17 mm, 21.50 mm and 0.00 mm,  respectively.

Conclusions: Based on the research results obtained, it can concluded that the miana extract were in the moderate categories as an antibacterial base ingredient. Miana extracts on all concentrations were more potent than amoxicillin.