Phytochemical Analysis and Antibacterial Efficacy of Nauclea Latifolia L (African Peech/Bon Bon Leave) Leaf Extracts Against Bacterial Isolates - Salmonella Typhi & Escherichia Coli

Abstract

Nauclea latifolia Sm, a useful medicinal plant belonging to the Rubiaceae family, is found in the humid tropical rainforest and West and Central Africa. This study aims to investigate the phytochemical constituents and antibacterial efficacy of Nauclea latifolia (African Peach/Bon Bon leaf) ethanol leaf extracts against two clinically significant bacterial pathogens: Salmonella typhi and Escherichia coli. Fresh leaves of N. latifolia were collected around the Fendall Campus, University of Liberia, dried and ponded into fine powder, 50g of the powder was macerated in 250mL of ethanol, resulting in a percent yield of 5.4%. After the Qualitative phytochemical screening of the phytoconstituents documented the presence of key bioactive compounds, including saponins, steroids, anthraquinones, flavonoids, alkaloids, tannins, and resins phytochemicals known for their therapeutic and antimicrobial properties. Antibacterial activity was assessed using the agar disk diffusion method, with ciprofloxacin as the standard control. The ethanolic extracts exhibited concentration dependent inhibitory effects on both S. typhi and E. coli, producing inhibition zones ranging from 16 mm to 22 mm, while ciprofloxacin demonstrated higher inhibition zones of 35 mm and 26 mm, respectively. Although the extract showed moderate antibacterial activity compared to the standard antibiotic, it remained effective and nonresistant within Clinical and Laboratory Standards Institute (CLSI) interpretation thresholds. These findings support the traditional medicinal use of N. latifolia and highlight its potential as a complementary agent in managing bacterial infections, especially in settings confronted with rising antimicrobial resistance. Further research is recommended to isolate active constituents, determine minimum inhibitory concentrations, and evaluate potential synergistic interactions with conventional antibiotics.