Effects Of Nutrients On Bioavailability And Bioaccessibility Of Polybrominated Diphenyl Ethers

As a class of persistent organic pollutants,polybrominated diphenyl ethers(PBDEs)are widely present in the environment.PBDEs can be harmful to the environment and human health.Bioaccessibility and bioavailability are two important factors in human exposure assessment.Dietary intake is one of the most important routes of exposure for PBDEs,and different nutrients can affect the bioaccessibility of PBDEs in food.Using the simulated human gastrointestinal tract,an experiment in vitro based on physiology was carried out to investigate the effects of oils,proteins,carbohydrates and dietary fibers on the bioaccessibility of PBDEs in fish.The results showed that the bioaccessibility of PBDEs in fish was 19.1-34.0%.The bioaccessibility of PBDEs in fish markedly increased when 0.001-0.08 g of oil,0.001-0.1 g of protein and 0.001-0.1 g of carbohydratecould were added.The bioaccessibility of PBDEs was increased by 10.7-35.0%,3.35-16.2% and16.2-35.1% when oil,protein and carbohydrate were added,respectively.However,the addition of 0.001-0.02 g of pectin had little effect on the bioaccessibility of PBDEs in fish.However,in vitro gastrointestinal digestion model did not have the intestinal epithelium to mimic uptake processes.Caco-2 cells were added to assess the effects of digestive juices of oil,protein,starch and pectin on bioaccessibility of PBDEs.The results showed that the transport ratio of PBDEs was significantly reduced by the digestive juices of different nutrients at the exposure concentration of 10 ng/m L.The transport ratio of PBDEs was decreased by 1.36-6.34% when 0.01-1 g of oil was added.The transport ratio was decreased by 1.59-4.94% when 0.15-1.5 g of protein was added.The transport ratio was decreased by 1.13-7.52% when 0.01-1 g of starch was added.And the transport ratio of PBDEs was decreased by 1.86-6.97% when0.01-0.3 g of pectin was added.Finally,the effects of nutrients on the bioavailability of PBDEs were studied by using mouse model.The results showed that the bioavailability of PBDEs in fish was reduced by 0.657-18.6% when oil,protein,starch and pectin were added.In conclusion,the uptake of PBDEs primarily occurred in the small intestine.The Caco-2 monolayer cell model was used to simulate the process of small intestine absorption,which was more similar to the actual human body absorption process and more accurate for the study of bioaccessibility.