Abstract

Background: Ceftriaxone belongs to the third-generation β-lactam antibiotics and it is useful for the treatment of a number of infectious diseases caused by both aerobic and anaerobic Gram-positive and Gram-negative bacteria. Phenylalanine is an essential aromatic amino acid of human being, from which dopamine and norepinephrine neurotransmitters are being synthesized. In the present study, we examined their combined efficacy against different types of pathogenic bacterial strains.

Objective: The aim of the study was designed to investigate the effects of ceftriaxone combination with phenylalanine on antimicrobial activity

Method: Gram positive-bacteria and Gram negative- including Klebsiella pneumoniae, – ATCC 25923, Proteus vulgaris, Escherichia coli, Serratia marcrescens, Staphylococcus epidermis, Alpha haemolyticus streptococcus, Enterococcus faecium, Pseudomonas aeruginosa, Listeria monocytogenes ATCC 7644, Enterococcus durans, Salmonella kentucky, Enterobacter aerogenes ATCC 13048 and Candida albicans ATCC 26555 were exposed to ceftriaxone and phenylalanine based on disk-diffusion method, and Minimum inhibition concentration (MIC) was determined with ceftriaxone.

Results: 0.3 mol/L ceftriaxone and 0.3 mol/L phenylalanine solutions were mixed and observed greater zone of inhibition than ceftriaxone or phenylalanine alone against above mentioned bacterial strains. These results might open up a new avenue for using phenylalanine in combination with ceftriaxone to lower MIC level for better antibacterial effect, to reduce side effects of antibiotics, and to reduce emerging threats of antibiotic resistance bacteria.

Conclusion: In this study, combined use of phenylalanine and ceftriaxone has revealed increased antimicrobial sensitivity against some selected both Gram positive and Gram negative bacteria in vitro.

Keywords: Ceftriaxone, phenylalanine, pathogenic bacteria strains, antimicrobial activity, beta-lactam antibiotics, bacterial strains.

Graphical Abstract