Inhibitory activity of bark and fruit extracts from Tetrapleura teraptera (Schumach. and Thonn) Taub against methicillin resistant Staphylococcus aureus (MRSA)

Abstract

Background: Tetrapleura tetraptera an indigenous African medicinal plant commonly known as Aridan fruit, has been reportedly used for traditionally treatments of various ailments including infectious diseases.

Objective: This study was designed to investigate the anti-methicillin resistant Staphylococcus aureus activity of Tetrapleura teraptera bark and fruit.

Methods: Pulverized parts were extracted into absolute methanol at room temperature and concentrated using rotary evaporator. Using agar well diffusion and agar dilution method, sensitivity test and minimum inhibition concentration (MIC) were determined against six strains of MRSA. Data were analyzed using Microsoft excel.

Results: Methanol extracts of bark and fruit elicit inhibitory properties on the six strains of MRSA. At 200 mg/mL, the bark showed most significant inhibitory activity against SA422 and with zone of inhibition (ZOI) of 27.65±0.35 mm compared to gentamycin of 17.95±0.05 mm, it also demonstrated significant inhibitory activities at different concentration on the other MRSA strains. At 200 mg/mL, the fruit extract was very active as compared with the standard drug, especially on SA422 where it showed similar and comparable (ZOI) of 19.5±0.50mm with gentamycin. The bark extract had the best minimum inhibition concentration (MIC) of 0.78 mg/mL for SA422, SA776, and SA423 while the fruit also had MIC of 0.78 mg/mL on SA422 and 423.

Conclusion: Methanolic extract of the bark showed great inhibitory activity against tested organism even at the lowest concentration, justifying its wide use in traditional management of infectious diseases.