M Yousefi1,2, N Shariatifar3, M Tajabadi Ebrahimi4, A M Mortazavian1, A Mohammadi1, N Khorshidian2, M Arab1, H Hosseini1. 1. Food Science and Technology Department, National Nutrition and Food Technology Research Institute, Faculty of Nutrition & Food Technology, Shahid Beheshti University of Medical Sciences, Tehran, Iran. 2. Food Safety Research Center (Salt), School of Nutrition and Food Sciences, Semnan University of Medical Sciences, Semnan, Iran. 3. Department of Food Safety and Hygiene, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran. 4. Department of Biology, Central Tehran Branch, Islamic Azad University, Tehran, Iran.
Abstract
AIMS: The current study aimed to investigate the ability of lactic acid bacteria (LABs) in removing four polycyclic aromatic hydrocarbons (PAHs) namely, benzo(a)pyrene (BaP), benz(a)anthracene (BaA), chrysene (Chr) and benzo(b)fluoranthene (BbF) from contaminated phosphate buffer saline (PBS). METHOD AND RESULTS: The effect of initial PAH concentrations (5, 10, 15, 20 μg ml-1 ), bacterial population (107 , 108 , 109 , 1010 CFU per ml) and pH (3, 5, 7) was studied to evaluate bacterial binding ability. All the tested bacteria could remove BaA, Chr, BbF and BaP from phosphate buffer solution and in almost all assays, removing of PAHs was as follows: BaP>Chr>BaA>BaF. Bifidobacterium lactis BB-12 had the lowest binding rate for all four PAHs, while the highest binding ability was related to Lactobacillus acidophilus LA-5. Moreover, cell viability was not required for the binding ability and even acid-treated, heat-treated and ultrasonic-treated bacterial cells showed more binding ability. The results showed that the bacteria-PAH complex was irreversible after washing with PBS. CONCLUSIONS: The removal of PAHs was significantly related to pH of media, strains of bacteria, type and concentration of PAHs SIGNIFICANCE AND IMPACT OF THE STUDY: This study has been focused on the reduction of polycyclic aromatic hydrocarbons using LABs and probiotics. Our results showed that not only live strains but also inactivated tested strains are able to remove PAHs from aqueous media, presenting new methods to diminish the amount of these contaminants in foods. Furthermore, the results of this study can be used in future research on evaluating the effects of oral administration of probiotic supplements and even dead probiotic strains on reducing PAHs in humans.
AIMS: The current study aimed to investigate the ability of lactic acid bacteria (LABs) in removing four polycyclic aromatic hydrocarbons (PAHs) namely, benzo(a)pyrene (BaP), benz(a)anthracene (BaA), chrysene (Chr) and benzo(b)fluoranthene (BbF) from contaminated phosphate buffer saline (PBS). METHOD AND RESULTS: The effect of initial PAH concentrations (5, 10, 15, 20 μg ml-1 ), bacterial population (107 , 108 , 109 , 1010 CFU per ml) and pH (3, 5, 7) was studied to evaluate bacterial binding ability. All the tested bacteria could remove BaA, Chr, BbF and BaP from phosphate buffer solution and in almost all assays, removing of PAHs was as follows: BaP>Chr>BaA>BaF. Bifidobacterium lactisBB-12 had the lowest binding rate for all four PAHs, while the highest binding ability was related to Lactobacillus acidophilus LA-5. Moreover, cell viability was not required for the binding ability and even acid-treated, heat-treated and ultrasonic-treated bacterial cells showed more binding ability. The results showed that the bacteria-PAH complex was irreversible after washing with PBS. CONCLUSIONS: The removal of PAHs was significantly related to pH of media, strains of bacteria, type and concentration of PAHs SIGNIFICANCE AND IMPACT OF THE STUDY: This study has been focused on the reduction of polycyclic aromatic hydrocarbons using LABs and probiotics. Our results showed that not only live strains but also inactivated tested strains are able to remove PAHs from aqueous media, presenting new methods to diminish the amount of these contaminants in foods. Furthermore, the results of this study can be used in future research on evaluating the effects of oral administration of probiotic supplements and even dead probiotic strains on reducing PAHs in humans.