Evaluation of Antibacterial Potency of Citrus Limon (Lemon) Juice Against Some Pathogenic Organisms as Alternative Source of Chemotherapy

The development of antibiotic resistance by pathogenic microorganisms have necessitated the quest for alternative drug therapy. The efficacy and safety of extract from Citrus limon for the development of alternative antibacterial drug using the cold-pressing extraction methods and column chromatography to obtain crude juice extracts and fractions respectively while the agar well diffusion and tube dilution methods were used to screen the juice extract and fractions for antibacterial activity against Salmonella enterica, Klebsiella pneumoniae, Streptococcus pneumoniae and Streptococcus pyogenes. A total of 277.5mL (12.313%) of juice was obtained from 2253.8g of fruit while the phytochemical analysis revealed the presence of 10 phytocomponents namely tannins, flavonoids, anthraquinones, alkaloids, steroids, phenols, cardiac glycoside, terpenes, resins and saponins. One hundred percent (100%) of the juice crude extract exhibited the highest activity with mean inhibition zones (MIZ) ranged from 25.00±0.57mm to 32.33±0.33mm while 25% (6.67±1.15mm to 10.00±1.00mm) exhibited the least activity. The minimum inhibitory concentration and minimum bactericidal concentration (MIC and MBC) for the juice crude extract ranged from 25% to 12.5% and 100% respectively while S. paratyphi C, S. typhi, K. pneumoniae and S. pneumoniae were still viable at 100%. Out of the three fractions eluted, only one (JEtOAc) was active against all the test organisms with MIZ ranged from 14.00±0.33mm to 22.33±1.20mm while 27 compounds were identified in the fractions by GCMS. Notable group of compounds identified include fatty acids, terpenes, aliphatic and aromatic hydrocarbons. The MIC and MBC for the fractions ranged from 30mg/mL to 15mg/mL and >120mg/mL to 30mg/mL. Based on these findings, it can therefore be concluded that the juice extract and ethyl acetate fraction of Citrus limon possess antibacterial activity due to the abundant presence of secondary metabolites and it is recommended that toxicity test be carried out on the crude extract and fraction for the development of alternative drugs for the control and treatment of infections caused by resistant organisms.