Phytochemical Screening and Microcidal Activity of the Ethanolic and Aqueous Extracts of Annona muricata against Some Pathogenic Bacteria

Objective: To investigate the phytochemical composition and evaluate the microbial activity of the ethanolic and aqueous extracts of Annano muricata against some pathogenic bacteria.

Methods: The leaf of Annano muricata from Annonaceae family which is used as herbal remedies for the cure of many ailments by natives in northern part of Nigeria, was collected in June, 2018 from the Professor’s Quarters of Modibbo Adama University of Technology (MAUTECH) Yola. The leaf was air dried, pulverized and extracted by simple overnight maceration technique and then analyzed. Aqueous extract of the aforementioned leaf was screened phytochemically for the determination of its chemical constituents which was then subjected to antimicrobial activity against Escherichia coli, Staphylococcus aureus, Staphylococcus epidermidis, Proteus vulgari, Salmonella typhi and Methicillin-resistant Staphylococcus aureus (MRSA).

Results: The result revealed the presence of alkaloid, tannin, flavonoid, volatile oil, triterpene, and saponin in the ethanolic extract of Annano muricata and tannin, flavonoid, alkaloid, triterpene, saponin in the aqueous extract of Annano muricata. The results of the antimicrobial activity carried out using disc diffusion method showed a zone of inhibition against tested organisms, with Escherichia coli being the most inhibited (27 mm) at concentration (1 mg/mL) with ethanolic extract followed by salmonella typhi (25 mm) at the same concentration with aqueous extract. At least concentration (0.125 mg/mL), almost all the organisms showed a zone of inhibition (6 mm) with the exception of Salmonella typhi (9 mm) with the aqueous extract and Proteus vulgari (9 mm) with the ethanolic extract of Annano muricata.

Conclusion: This study conclusively demonstrate that Annona muricata is a better source of various phytochemicals like: tannin, alkaloid, saponin, flavonoid, triterpenoid, phenol and also justify the use of the plant as bactericidal agent for the treatment of so many diseases.