Study On The Form Of Aluminum In Enteromorpha Prolifera

Enteromorpha prolifera is a kind of green nutrition food with low fat,high protein,high fiber and rich mineral content,but in recent years,it has been frequently detected that the aluminum content is seriously exceeded.Aluminum has low solubility under neutral conditions,and has been considered as a non-toxic element in the past.In recent years,a large number of studies have shown that aluminum has neurotoxicity,reproductive toxicity and immunotoxicity at a certain dose,and it has potential connection with Alzheimer’s disease,Parkinson’s disease,osteoporosis and other diseases.The toxicity of aluminum is not determined by the total aluminum content,but closely related to its existing form.The toxicity of different forms of aluminum is far from each other.In order to ensure the edible safety of Enteromorpha prolifera,it is necessary to analyze the different forms of aluminum in Enteromorpha prolifera and its combination mechanism.In this paper,the distribution and existing forms of aluminum in Enteromorpha prolifera were analyzed,and the combination mechanism of polysaccharide aluminum was revealed.In order to provide the necessary support for the scientific evaluation of Enteromorpha Enteromorpha,and provide the theoretical basis for the detection of active aluminum in Enteromorpha Enteromorpha.At the same time,it can also fill the blank of aluminum binding mechanism in Enteromorpha prolifera.The specific research results are as follows:1.It speciation and distribution of aluminum in Enteromorpha prolifera were revealed.The results show that the active aluminum is mainly trivalent aluminum ion,hydroxy ground aluminum and aluminum fluoride,accounting for only 8.57%～11.38%.The stable aluminum is mainly combined with soluble polysaccharide,protein,fiber,etc.,accounting for 88.62%～91.43% of the total aluminum,among which the aluminum combined with soluble polysaccharide is the highest,accounting for 39.76%～42.08% of the total aluminum,while the fat can not be combined with aluminum.At the same time,aluminum is mainly distributed in the polysaccharides,proteins and fibers between cell walls,and only a small amount of aluminum is distributed in the cells in a free state.2.Study on the adsorption process and binding mechanism of Enteromorpha Enteromorpha and aluminum.The results show that the adsorption of aluminum by Enteromorpha prolifera is a dynamic equilibrium process.It is found that the adsorption of aluminum by Enteromorpha prolifera may be related to the electronic covalent force between metal ions and the functional groups and charges on the surface of Enteromorpha prolifera.The correlation coefficient R~2 of Langmuir dynamic fitting formula is 99.5±0.02,which is more consistent with the adsorption process of aluminum by Enteromorpha Enteromorpha.At the same time,aluminum was mainly bound to cellulose and hemicellulose in Enteromorpha prolifera And O-H in carbohydrates such as polysaccharides,O-H in carboxy group and C-O in ether group,ester group,alcohol and phenols in roots,but not methyl in oil compounds in cell wall and membrane components.3.The binding mechanism of polysaccharide aluminum in Enteromorpha prolifera was revealed.The results show that EPP-1,EPP-2 and EPP-3 are all pyranopolysaccharides,EPP-2 may beβ-D-glucopyranose and protein complex acid polysaccharide,EPP-3 may beβ-D-glucopyranose acid polysaccharide,and the content of aluminum is 38.75%-40.38%,7.21%-8.72%,9.21%-10.53%,respectively.According to the infrared spectrum analysis before and after the adsorption of aluminum by Enteromorpha prolifera margin polysaccharide,aluminum is mainly combined with ester group in EPP-1,C-O of O-acetyl,C-O-C,C-O-H andα-glycoside bond of pyran ring;with C-H bond,ester group,O-acetyl,α-glycoside bond andβ-D-glucopyranose ring in EPP-2;with ester group,O-acetyl andα-glycoside bond in EPP-3.