Determination of Ochratoxin-A Detoxification and Antibiotic Resistance Potential of Acinetobacter calcoaceticus

Abstract

The ochratoxin A (OTA) is a mycotoxin which is present in food products as a contaminant, and it is one of the hazardous toxins causing health risks in animals and humans. One of the main health issues is the damage to kidneys. The most adopted technique used in detoxification of this mycotoxin is biodegradation. In this study, Acinetobacter calcoaceticus isolated from soil samples was used for the detoxification of ochratoxin, and also this study explains the antibiotic resistance potential of this organism. Acinetobacter calcoaceticus was tested to see if they could break down ochratoxin A(OTA). Acinetobacter calcoaceticus was shown to be able to break down OTA among the tested microorganisms. We tested the ability of A. calcoaceticus to degrade OTA in LB medium at 25 and 28°C, with OTA concentrations of 2ppm, 6ppm, and 10ppm. A. calcoaceticus was able to break down OTA from a starting concentration of 10 (g/ml) at these conditions. At 25 and 30°C, A. calcoaceticus removed an average of 0.1005 and 0.0636 (g/ml/h of OTA, respectively, from a medium containing an initial concentration of 10 (g/ml). A. calcoaceticus degraded ochratoxin A significantly during and after the log phase of cell development at both incubation temperatures. The hypothesis is that A. calcoaceticus degraded OTA into an ochratoxin with reduced toxicity. At the same time the potential of this microorganism strain was also measured using susceptibility testing and it showed the potential of development of its resistance. Strains of Acinetobacter calcoaceticus isolated from soil samples were tested for their susceptibility against different unrelated classes of antibiotics. A. calcoaceticus was resistant to multiple antibiotics. In vitro degradation assays were used exposing the toxin to the degrading enzyme or microorganism in a controlled laboratory environment. The degradation of the toxin was monitored using various techniques such as high-performance liquid chromatography (HPLC). The significance of this study is to highlight the capability of the Acinetobacter calcoaceticus in degrading ochratoxin A, so that health risks associated with it can be reduced; also, the antibiotic resistance potential measurement helps in development of optimum antimicrobial strategy.