Anti-inflammatory, anti-bacterial and antioxidant activities of Thai medicinal plants for diarrheal treatment

A Thai traditional remedy called Thatbunjob (TBJ) is normally used to treat abdominal pain, diarrheal disease and health promotion in the list of National herbal medicinal products A.D.2011 of Thailand. Its formula consists of 23 plants. The objective of this investigation was to study on antioxidant, anti-bacterial and anti-inflammatory activities of extract from TBJ and each plant component. The antioxidant assay by DPPH radical scavenging assay [1], antimicrobial assay by disc diffusion [2] and anti-inflammatory assay by inhibition nitric oxide release on lipopolysaccharide (LPS) induction in RAW 264.7 cells [3] were determined. The extraction of TBJ was imitated by traditional using (ethanolic and water extract gave drug: extract ratio as 100:9.85 and 100: 10.40). The results were found that water and ethanolic extracts of TBJ showed stronger antioxidant activity than BHT (EC₅₀= 7.22 ± 0.72, 13.52 ± 0.99 and 14.55 ± 0.69 µg/ml. respectively). The water extract of Zingiber officinale Roscoe as one component of TBJ exhibited the higher inhibitory effect on nitric oxide production in RAW 264.7 than indomethacin (IC₅₀ = 2.06 ± 0.09 and 20.32 µg/ml). The ethanolic extract of TBJ also exhibited moderate inhibition of NO production (IC₅₀= 27.48 ± 1.25 µg/ml). The ethanolic extract of TBJ exhibited against six diarrheal strains such as Vibrio. parahaemolyticus, Staphylococcusaureus, Vibrio cholerae, Shigella dysenteriae, Escherichia coli, Salmonella typhi (MIC = 0.625,1.25,2.5,2.5,5,5 mg/ml) and gentamycin as positive control. It was considered as moderate antibacterial activity. It concluded that TBJ extract had a potential therapeutic agent for abdominal pain, diarrheal disease and health promotion.

References:

[1] Yamazaki, K. et al. (1994) Chem. Pharm. Bull., 42: 1663 – 1665.

[2] Tewtrakul, S. and Subhadhirasakul, S. 2008. J.ethnopharmacol: 120; 81 – 84.