Antimicrobial Activity of Ethyl Acetate and Ethanol Seed Extracts of Buchholzia coriacea (Wonderful Kola) against Multidrug-Resistant Clinical Isolates of Salmonella Species and Escherichia coli

The increasing failure of chemotherapeutics and antibiotic resistance exhibited by pathogens has led to screening of several medicinal plants for their antimicrobial potentials. This study was designed to determine the efficacy of ethanol and ethyl acetate seed extracts of Buchholzia coriacea against multidrug-resistant E. coli and Salmonella species isolated from urine samples of patients with urinary tract infections (UTIs) visiting Federal Teaching Hospital Abakaliki. One hundred and sixteen (116) bacterial pathogens (E. coli=80; Salmonella species=36) isolated from urine samples of UTI patients were subjected to antibiotic susceptibility testing using KirbyBauer disc diffusion technique. The antibacterial activity of ethanol and ethyl acetate seed extracts of Buchholzia coriacea against E. coli and Salmonella species was determined using agar well diffusion technique. Phytochemical screening for the presence of bioactive compounds in Buchholzia coriacea was done using standard analytical method. Results showed that E. coli and Salmonella spp. were generally susceptible to ertapenem, imipenem, gentamycin, ceftriaxone, and aztreonam but resistant to amoxicillin and nitrofurantoin. Ethanol and ethyl acetate seed extracts of Buchholzia coriacea had no activity against all the test organisms. Phytochemical screening results of Buchholzia coriacea seed extracts indicated the presence of some secondary metabolites such as saponin, tannin, flavonoids, alkaloids, phenolics, and anthocyanins which are beneficial to man's health for the prevention and management of diseases/ infections. Thus, this study revealed that ertapenem, imipenem, and gentamicin are still active against uropathogenic bacteria (E. coli and Salmonella species) while seed extracts of Buchholzia coriacea were ineffective and cannot be used as an alternative therapeutic choice in treating UTIs. Therefore, it is imperative to carry out awareness campaigns, especially in developing countries, to curtail the trend in consumption of some acclaimed herbal/ medicinal plants for the treatment of infectious diseases until scientific study on their therapeutic potentials is carried out.