Objective: The goals of this investigation were to identify the species of the producers and ascertain the dose-dependent effect of extracellular products of Indonesian bacteria that generate β-lactamases inhibitors.
Methods: An agar diffusion technique for the lactamase inhibitor activity assay was performed. Observation of bacteria using phenotypic analysis was performed by observing colony color and cell shape morphology, biochemical assays and a series of carbohydrate fermentation tests. Bacterial identification was performed by comparing the nucleotide sequence of the 16S rDNA gene of target bacteria with available nucleotide sequences in Gene Library (NCBI). Combining data from phenotypic and genotypic analyses allowed for the identification of the producers.
Results: According to our findings, none of the bacteria's extracellular products, which contain β-lactamase inhibitors in a range of concentrations, showed a discernible impact on the values of the inhibition zone. The producers are Aeromonas popoffii, Alcaligenes faecalis, Streptomyces brasiliensis, Staphylococcus equorum, Pseudomonas putida, Pseudomonas fluorescens, Salmonella typhi, Enterobacter hormaechei, Serratia marcescens and Enterobacter sp. The highest potency of β-lactamase inhibitor was provided by the extracellular product of VR3 isolate bacteria which was identified as Serratia marcescens.
Conclusion: In conclusion, this study clearly showed that our isolated bacteria have the potential to be further investigated in order to maximize the recovery of β-lactamase inhibitor compounds
