Antimicrobial, Antioxidant and In Vivo Toxicity Studies of Triumfetta rhomboidea Jacq Leaf Extract in Male Wistar Rats

Abstract

Although Triumfetta rhomboidea (TR) has found its place in folklore medicinal applications, the scientific basis of these applications is poorly understood. This study examined the antioxidant and antibacterial properties of TR and its potential alteration of the renal and liver functions. The chemical constituents and antioxidant capacity of the ethanol extract of TR leaves were determined using FTIR, GC-MS and standard methods, and the agar well diffusion method was used to measure the antimicrobial activity. For the toxicity study, fifteen rats were divided into three groups: A – C; control, 200 mg/kg and 300 mg/kg ethanol TR extract per body weight administered orally for fourteen days. Biochemical assays were performed on the plasma, liver and kidney homogenates, and histo-pathological changes were examined in the tissues. Results showed that TR leaves contain total flavonoids (0.1316 ± 0.0001 mg/ GAE/100g) and total phenols (0.13 ± 0.0002 mg GAE/100g). GC-MS analysis of the leaf extract showed the presence of 44 major compounds. The extract demonstrated significant inhibitory activity against Bacillus cereus, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Salmonella typhimurium. Biochemical assay revealed no significant effect on the liver and renal function changes compared to the control group, except for the critical (p< 0.05) increase in Na. The antioxidant parameters in both the kidney and liver homogenates of TR-treated rats were not significantly altered except for reduced SOD levels at 200 mg/kg. Histopathological assay revealed relative degenerative changes in the two organs. TR leaves have antimicrobial and antioxidant properties, but could be toxic to the liver and kidneys at high doses.