Abstract:
The increasing prevalence of antibacterial resistance and oxidative stress-related diseases has led to an increased interest in the search for natural therapeutic agents from medicinal plants. Hence, this study investigated the phytoconstituents and evaluated the antioxidant and antibacterial activities of the leaves and tubers of Icacina oliviformis. Extraction was conducted by maceration using ethanol (30% and 70%), and was subjected to qualitative phytochemical screening. FTIR and LC-HRMS were used for chemical characterization and metabolite profiling. Quantitative phytochemicals (phenols, flavonoids, and tannins) were analysed using standard colorimetric assays, while antioxidant activity was evaluated using the DPPH assay method. Antibacterial activity was assessed using agar disc diffusion against Escherichia coli, Bacillus cereus, Pseudomonas aeruginosa, Staphylococcus aureus, and Salmonella typhi. Qualitative phytochemical analysis revealed the presence of flavonoids, phenols, alkaloids, and terpenes. FTIR analysis also confirmed the presence of functional groups such as O-H, C-H, C=O, and C-O, which are associated with phenolic and aromatic compounds typical of medicinal plants. LC-HRMS tentatively identified metabolites such as scopanarin, violanthin, chlorogenic acid, glucocaffeic acid, isovitexin, vitexin, shaftoside, lutonarin, ligstroside, clovamide, verbascose, scoparin, isoscoparin, azelaic acid, and lutexin, some of which, for the first time, are reported in I. oliviformis. The 70% ethanolic leaf extract exhibited the highest phenolic and flavonoid contents (199.29 ± 1.84 mg GAE/g and 452.90 ± 13.92 mg QE/g, respectively), while the 70% ethanolic tuber extract had the highest tannin content (17.14 ± 0.52 mg TAE/g). All the extracts showed strong free radical scavenging activity, with the lowest IC_50 value observed in the 70% ethanolic leaf extract (15.37 ± 0.29 µg/mL), which demonstrated stronger activity than the standard ascorbic acid (16.56 ± 0.18 µg/mL). Amongst all the extracts, the highest antibacterial activity was observed in the 70% ethanolic leaf extract against P. aeruginosa and S. typhi with MIC values of 12.5 mg/mL. Overall, the leaf extracts exhibited greater bioactivity than the tuber extracts, indicating that Icacina oliviformis is a promising source of natural therapeutic agents, with potential application in the food, feed, cosmetic, pharmaceutical, and nutraceutical industries.
Keywords: Icacina oliviformis, antioxidant, antibacterial, phytochemicals, LC-HRMS, FTIR
Biography:
Mr. Adonai Yin-Anaab Kunduzore is a researcher at the University of Technology and Applied Sciences with an MPhil in Biochemistry and Molecular Biomedicine and a Bachelor’s degree in Biochemistry. My research interest focus on drug discovery and the development of novel therapeutic strategies to address antimicrobial resistance and oxidative stress. With my background in biochemistry and molecular biomedicine, I am particularly interested in identifying and developing promising compounds that can contribute to combating drug resistant pathogens as well as oxidative stress and addressing emerging challenges in infectious disease treatment.
