The Effects Of Lactobacillus Plantarum P9 On Alleviating Cadmium And Lead Toxicity

Cadmium and lead are two toxicity heavy metals.Excessive exposure causes a variety of health effects.Previous studies have demonstrated that Lactic acid bacteria(LAB)strains can efficiently adsorb different heavy metals.The Lactobacillus plantarum P9 strain is a novel probiotic strain that has shown convincing health-promoting effects and excellent pesticide-degrading activity.Thus,this study aimed to investigate the capacity to reduce the toxicity of cadmium and lead,and evaluate the effect of P9-supplemented to lower heavy metals in populations of farmers in Kaifeng City.The main results are as follows:1.Firstly,the cadmium and lead adsorption,tolerance,and antioxidant capacity of L.plantarum P9 were evaluated.L.plantarum P9 has an adsorption advantage for lead,and the adsorption rates at 10 mg/L and 50 mg/L lead concentrations were 36.2% and 24.3%,respectively.At the same time,this strain also had significantly better cadmium and lead tolerance.With the evaluation of DPPH radical scavenging,hydroxyl radical scavenging and reducing activity,P9 exhibited good antioxidative capacity.The above experimental results showed that P9 can effectively adsorb cadmium and lead,and reduce the toxicity of cadmium and lead.2.The pH value,temperature and cell concentration have a great influence on the adsorption effect of L.plantarum P9 on cadmium and lead.The results show that:(1)As the pH value increased,the adsorption quantity also increased,and when the pH is 5,the maximum adsorption of cadmium is 1.87 mg/g;the maximum adsorption of lead at pH 6 is3.49 mg/g;(2)At 37? and 45?,the maximum adsorption of cadmium and lead were 2.05mg/g and 3.41 mg/g,respectively;(3)As the cell concentration increased,which would decrease adsorption capacity and increase efficiency.3.Fourier infrared spectroscopy scanning results show that the active groups such as amino,carboxyl and phosphoric acid groups on the surface of L.plantarum P9 bacteria are involved in the adsorption process of cadmium and lead.When the amino and carboxyl groups are masked,the cadmium and lead adsorption ability of L.plantarum P9 decreased significantly.The Langmuir isothermal model predicts that the theoretical maximum adsorption capacity of L.plantarum P9 for cadmium and lead is 1.94 mg/g(wet bacteria)and 3.58mg/g(wet bacteria),respectively.In summary,L.plantarum P9 can adsorb cadmium and lead efficiently and stably,and the adsorption sites are mainly concentrated on the surface of the cell wall.4.We want to investigated the potential for L.plantarum P9-supplemented to lower toxic heavy metal levels in at-risk populations.The results showed that after 30 days of intervention,compared with the placebo group,the blood cadmium content increased significantly(P < 0.05),while the probiotic group remained stable;the urine lead content of the probiotic group increased significantly(P < 0.001),the urine cadmium content also showed a trend to decrease(P = 0.07),while there was no change in the placebo group.The above results indicate that the intake of L.plantarum P9 helped maintain the stability of blood cadmium content,and accelerated the excretion of cadmium and lead in the urine.This paper combined in vivo and in vitro experiments to evaluate the probiotic effects of L.plantarum P9.It was found that L.plantarum P9 could effectively adsorb cadmium and lead,and accelerated the excretion of toxic heavy metals.