Potential Use of Chromolaena odorata Linn. Flavonoids against Escherichia coli Induced Diarrhoea in Mice

ABSTRACT flavonoids are important chemotaxonomic markers for the genus Chromolaena. Chromolaena odorata Linn. (CO) is used in folklore medicines to treat gastrointestinal diseases such as diarrhoea. This study examined the feasibility of total flavonoids from C. odorata (TFCO) as an antibacterial agent in vitro, and the mechanism of action of TFCO in combating Escherichia coli-induced diarrhoea in mice. MBC and MIC values of 0.25 and 0.125 g TFCO/ml showed it was effective as an antibacterial agent against E. coli (CMCC 44752) in vitro. Ninety Kunming mice were randomly divided into five groups of 18 mice per group (1 male: 1 female). The groups were control (saline), negative control (E. coli + 0 mg/kg TFCO), low dose (E. coli + 10 mg/kg TFCO), medium dose (E. coli + 40 mg/kg TFCO), and high dose (E. coli + 160 mg/kg). TFCO was administered by gavage 3 h post intraperitoneal (i.p) E. coli injection. Serum IgM, IgA, IgG, TGF-β1 mRNA expression in duodenal villi, and histopathology of duodenum were also studied. TFCO significantly increased the IgA and IgG concentration (P