The pulp and seed of Star apple, Chrysophyllum cainito, was analyzed for its nutrients, anti-nutrients, antimicrobial potentials and microbial profile, using standard methods. The microbial count of the fruits ranged from 1.0x109 to 2.4x1010 for the total aerobic plate count, 1.0x107 to 2.0x107 for fungal count and 1.0x108 to 1.2x109 for coliform count. The identities of the normal flora on the surfaces of healthy fruits and of spoilage organisms were confirmed to include species of Bacillus, Corynebacterium, Staphylococcus, Micrococcus, Acinetobacter, Enterococcus, and Pseudomonas (which are all pathogenic microorganisms). The fungal isolates include species of Rhizopus, Aspergillus, Penicillum and Saccharomyces. The high bacterial and fungal counts and their presence, portend a serious health implication. Aspergillus and Penicillium species produce mycotoxins involved in mycotoxicosis of humans and animals. Staphylococcus and Bacillus species produce potent toxins implicated in food borne illnesses, while the presence of Enterococcus indicates faecal contamination. Vitamins such as vitamin A (0.027mg to 0.089mg) and vitamin C (10.0mg to 43.54mg) were also present. Minerals such as calcium, magnesium, phosphorus, potassium and sodium were present at concentrations of 37.0mg, 5.0mg, 8.0mg, 38.0mg and 21.0mg respectively, for the pulp extract’s. Chrysophyllum cainito is a good source of minerals, which are needed for electrolyte balance, neurotransmission, development of strong teeth and bones. The proximate composition of star apple consists of protein (1.96 g to 4.63g), moisture (56.04g to 75.90g), fat (0.88g to 15.81g), fibre (2.31g to 4.19g), ash (0.56g to 0.84g) and carbohydrate (18.39g to 78.49g). Varying concentrations of phytochemicals such as spinning, flavonoids, tannin, steroid and cardiac glycoside were detected. The seed and pulp showed varying levels of antibacterial and antifungal activities against some clinical isolates such as Escherichia coli and species of Salmonella, Staphylococcus, Pseudomonas, Aspergillus, Candida and Penicillium. Chrysophyllum cainito holds great potentials as an antimicrobial agent for chemotherapeutic medicine and it is a rich source of nutrient and phytochemicals. Regular consumption of this fruit should be encouraged for its potential nutrition and health benefits.Keywords:
Chrysophyllum cainito, anti-nutritive composition, antimicrobial activity.