Antimicrobial activity of selected nutraceutical plants used in Northern Uganda

Background: Nutraceutical plants (NP) play a vital role as supportive treatment with antiretroviral drugs (ARVs). However, there is limited  scientific evidence on the efficacy of NP to justify their extensive use. This study aimed to evaluate the antibacterial activity of three nutraceutical plants which are commonly used as antimicrobials. Methodology: Leaves of Cajanus cajan L. Millsp. and Eucalyptus globulus Labill., and stem bark of Mangifera indica L. were collected from  Northern Uganda. The three samples of each NP were extracted with acetone and the minimum inhibitory concentration (MIC) values of  the extracts against Staphylococcus aureus, Streptococcus pneumoniae, Pseudomonas aeruginosa and Klebsiella pneumoniae were determined using the serial broth microdilution technique [1]. The mean MIC values of the extracts against each bacterial species were  recorded. Results: The three NP extracts were active against all the four bacteria species with MIC ranging from 0.08 to 2.5 mg/ml. The extract of  Cajanus cajan was very active against Klebsiella pneumoniae with the lowest recorded MIC value of 0.08 mg/ml. The extract of Mangifera  indica bark was very active against Pseudomonas aeruginosa with the lowest MIC of 0.08 mg/ml. Conclusion: The results of the present  study support the traditional use of the nutraceutical plants as antimicrobials.