Antimicrobial and Phytochemical Properties of Atuna racemosa Raf. Kernel Extract

Atuna racemosa Raf., a forest tree used to season raw fish dish in the Philippines, is proven to have antibacterial properties. The study aimed to help elucidate the significance of using its kernel as a condiment and consequently, increase its value by assessing its antimicrobial and phytochemical properties. The antimicrobial activity of its ethanolic extracts were screened against Bacillus cereus, Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Salmonella enterica ser. Typhimurium, Aspergillus niger, Saccharomyces cerevisiae and Candida albicans using agar disc diffusion technique. Qualitative phytochemical screening was done, and total phenolic content was determined at a concentration of 100 mg dry sample per 1 mL solvent. The extract showed bacterial growth inhibition in Staphylococcus aureus, Pseudomonas aeruginosa and Bacillus cereus while a mild antifungal activity against Aspergillus niger was observed. Phytochemical analysis detected the presence of cardiac glycosides, tannins, phenolic compounds and saponins in the extract. It yielded a total phenolic content of 42.7 mg GAE/100 g. This denotes that the kernel of A. racemosa has the potential to be classified as a natural food preservative and functional food.