Antioxidant and Antibacterial Activities of Selected Medicinal Plants from Addis Ababa against MDR-Uropathogenic...

This study determined the antioxidant and antibacterial activities of Thymus schimperi (Ts), Rhamnus prinoides (Rp), and Justicia schimperiana (Js) from Addis Ababa against MDR-Uropathogenic bacteria. Accordingly, Thymus schimperi had the highest total phenolic (TPC), flavonoid (TFC) and proanthocyanidin content. In Ts, the GC-MS analyses predicted 14 bioactive compounds. And among these, hexanedioic acid, bis(2-ethylhexyl) ester, thymol, and o-cymen-5-ol were the most predominant compounds, respectively. Six compounds were also predicted in Rp, where hexanedioic acid, bis(2-ethylhexyl) ester, β-D-glucopyranoside, methyl, and desulphosinigrin were the predominant, respectively. Whereas in the Js extract, five bioactive compounds were predicted, with hexanedioic acid, mono (2-ethylhexyl) ester, debrisoquine, and 8,11,14-heptadecatrienoate, methyl ester being predominant compounds, respectively. The extracts' TPC showed a strong negative correlation with the DPPH (2,2-diphenyl-1-picrylhydrazyl) assay (r = -0.999; p = 0.023). In addition, the TFC correlated significantly with the ABTS (2,2'-azino-di-(3-ethylbenzthiazoline sulfonic acid)) assay (r = 0.999; p = 0.032). Thymus schimperi showed the highest antibacterial activity against clinical isolates of Escherichia coli and Klebsiella pneumoniae ESBL at 1000 mg/mL, and Ts had the lowest MIC (4 mg/mL) among evaluated extracts against E. coli (ATCC25922). In conclusion, Ts and Rp possess higher predicted bioactive molecules, including antioxidant and antibacterial activities, which are potentially useful in treating urinary tract infections.