In recent years, plant products have been reported to be efficient anti-microbial agents without side effects. Annona squamosa L. (Family: Annonaceae) is traditionally used in treating diarrhoea, dysentery, colds, chills, rheumatism, and sleeplessness. It also has an anticancer function. The seed oil is used against agricultural pests.
The present study focused on investigating the antibacterial activity of hexane, petroleum ether, chloroform, and ethanol extracts of A. squamosa seeds.
All the extracts were screened qualitatively for chemical constituents. The antibacterial activity of seed extract was evaluated by the agar well diffusion method against five pathogenic bacteria in five different concentrations (10, 5, 2.5, 1.25, and 0.625 mg) of the extract. The zones of inhibition were measured in mm.
Alkaloids, carbohydrates, glycosides, saponins, proteins, amino acids, phenols, flavonoids, terpenoids, steroids, tannins, anthraquinones, and quinones were detected. The tested organisms were susceptible to all the extracts at different concentrations. 10 mg hexane extract showed the highest zone of inhibition in cultures of Enterobacter cloacae (15 mm) and Escherichia coli (14 mm). Petroleum ether extract at 10 mg was effective against Escherichia coli (13 mm) and Klebsiella pneumoniae (12 mm). The chloroform extract was effective against Enterobacter cloacae (18 mm) and Escherichia coli (14 mm) cultures at 10 mg concentration. The zone of inhibition formed by 10 mg ethanol extract was highest in Escherichia coli (18 mm) and Staphylococcus aureus (18 mm). Conclusion: Our results confirm that A. squamosa seed extract has anti-bacterial efficacy due to the presence of various active principles in the extracts.