Antibacterial activity of aqueous and methanolic extracts of Ficus Natalensis (Natal Fig) stem bark against laboratory archived isolates of Neisseria Gonorrhoeae

Abstract

Antimicrobial resistant Neisseria gonorrhoeae is a public health challenge globally. Due to the development of antimicrobial resistance worldwide, natural products from higher plants have traditionally been regarded as important sources of antimicrobial agents. These have attracted extensive attention in fundamental research and clinical applications. WHO indicates about 80% of the African population uses traditional medicine for primary health care and in most of the African countries, traditional healers administer plant remedies to patients suffering from sexually transmitted infections. Therefore, the present study aimed at investigating the antibacterial activity of aqueous and methanolic stem bark extracts of Ficus natalensis against laboratory archived isolates of Neisseria gonorrhoeae. Aqueous and methanolic extracts of Ficus natalensis stem bark were prepared and tested using agar-well diffusion method against laboratory archived isolates of Neisseria gonorrhoeae cultured on sterile plates of chocolate Agar. Minimum inhibitory concentrations for both extracts were also determined. Ceftriaxone and sterile distilled water were used as positive and negative controls respectively. Both aqueous and methanolic Ficus natalensis stem bark extracts showed antibacterial activity against laboratory archived isolates of Neisseria gonorrhoeae, Aqueous stem bark extract showed higher antibacterial activity than methanolic extract. Methanolic stem bark extract had a higher minimum inhibitory concentration (MIC) compared to that of aqueous extract (MIC). Therefore, both the aqueous and methanolic extracts of Ficus natalensis stem bark show antibacterial activity against laboratory archived isolates of Neisseria gonorrhoeae; the aqueous extract having the higher activity. The finding that Ficus natalensis has antibacterial effect serves to suggest that there is a potential in discovering novel antibacterial agents from bark cloth tree. This however needs further investigation.