Efficiency of dairy strains of lactic acid bacteria to bind bisphenol A in phosphate buffer saline

Bisphenol A (BPA) is an endocrine disruptor widely used in plastics and resin for food packaging. BPA migration to foods is believed to be a major source of human exposure of BPA. Lactic acid bacteria (LAB) are a promising solution to reduce exposure to toxins. The aim of the present study was to investigate the removal of BPA from aqueous solution by six LAB strains from commercial fermented dairy products. Effects of the bacteria viability, bacteria concentration, BPA concentration, incubation time, and temperature on the binding ability were tested. In addition, binding stability was determined by washing the bacteria BPA complexes with phosphate buffer saline (PBS). A considerable proportion (24.48%-50.80%) of BPA was removed from the aqueous solution by the six viable LAB strains. Moreover, an enhancement of bacterial ability to bind BPA was observed for nonviable strains via heat or acidic treatment. Binding was dependent on the bacterial concentration, initial BPA concentration, and incubation temperature. In addition, binding of BPA by six LAB strains was a rapid reaction. The reduction of BPA in the PBS solution was observed to reach a high level after 15 min of incubation time. The results on binding stability indicated that all strains tested show reversible binding on BPA, and the binding of Lactobacillus acidophilus and Lactobacillus plantarum on BPA was more stable, with 48.11% and 53.24% released in the PBS solution, respectively. In contrast to the viable cells, heat and acid treatments markedly enhanced the stability of the bacteria BPA complexes. The binding capability of the six LAB strains towards BPA could provide potential for detoxification of contaminated foods and reduction of the bioavailability of BPA in the human diet and animal feed. (C) 2016 Elsevier Ltd. All rights reserved.