Antibacterial Activity of Thai Medicinal Plants Pikutbenjakul
Sumalee Kondo PhD*, Chisanucha Sattaponpan BSc**, Souwalak Phongpaichit PhD***, Apichai Srijan BSc****, Arunporn Itharat PhD*****
Affiliation : * Department of Preclinical Science, Faculty of Medicine, Thammasat University, Pathumthani, Thailand ** Research section, Faculty of Medicine, Thammasat University, Pathumthani, Thailand *** Department of Microbiology, Faculty of Science, Prince of Songkla University, Songkhla, Thailand **** Department of Enteric Diseases, USAMC-AFRIMS, Bangkok, Thailand ***** Department of Applied Thai Traditional Medicine center, Faculty of Medicine, Thammasat University, Pratumthani, Thailand
Background : Bacterial infections caused by resistant strains have been increased dramatically. Pikutbenjakul, a Thai
medicinal plant formula containing Piper longum, Piper sarmentosum, Piper interruptum, Plumbago indica and Zingiber
officinale have been widely used in Thai traditional medicine.
Objective : To determine antimicrobial activity of Pikutbenjakul formula and its components in order to develop the medicinal
plants for alternative treatment of bacteria causing diarrhea.
Material and Method: Activity of Pikutbenjakul formula and its components was tested using disc diffusion and broth dilution
methods against bacteria associated a set of bacteria associated with diarrheal disease including Vibrio cholerae, Vibrio
vulnificus, Salmonella, Shigella, Escherichia coli (EIEC, ETEC, EPEC, EAEC and EHEC) and Staphylococcus aureus. The
extraction was performed by maceration in 95% ethanol.
Results : The results showed all tested strains were susceptible to P. indica while other components were able to inhibit some
strains. P. sarmentosum showed antimicrobial activity against Vibrios with the MIC values between 0.625 to > 5mg/ml. P.
sarmentosum, P. indica and Pikutbenjakul formulas inhibited the growth of all Vibrios. P. interruptum inhibited V. cholerae
serogroups O1 and non-O1/non-O139. P. longum was able to inhibit only two isolates of V. cholerae serogroup O139 (MIC
= 1.25 mg/ml) and V. vulnificus (MIC > 5 mg/ml). The activity of Pikutbenjakul containing Zingiber spp. and Pikutbenjakul
containing Z. officinal against Vibrios, Shigella spp. and S. aureus was not significantly different. P. indica could inhibit
Salmonella (MIC > 5 mg/ml), E. coli (MIC > 5 mg/ml) and S. aureus (MIC = 1.25 mg/ml).
Conclusion : The results support the Thai medicinal plants for treatment of diarrhea caused by these bacteria. This study also
provides an insightful knowledge on antimicrobial activity which would lead to further development of an effective formula of
Pikutbenjakul for diarrheal disease and other infectious diseases in future.
Keywords : Antibacterial activity, Pikutbenjakul, Diarrheal disease
