Studies On The Degradation Of Organophosphorus Pesticides By Some Polysaccharides REE Complexes

Organophosphate is the main sort of the pesticides in common use currently. Organophosphorus pesticide has been produced at a great deal and used widely domestic and overseas at all times. But after the organophosphate completed the effects of poisoned target pests, there is at a certain extent residual on the food and in the environment. There are many methods of the degradation on the organophosphorus pesticide at present, for example: utilizing the microbe and microbial enzymes, the photocatalysis degradation and the ultrasonic degradation et al. But the above-mentioned techniques are difficult to be applied to the actual process of the food production because of some usage limitations. So people give theirs' attention to research the effective and convenient methods of degradation on the organophosphorus pesticide.Rare earth elements (REE) and their complexes have special physical and chemical properties and have been widely applied in nearly every aspect. But the allowance of REE added to food has been strictly limited and REE can't be efficiently used in neutral liquor, due to their insolubility at neutral system, meanwhile REE also has potential pollution for the environment. So people pay more and more attention to the state of REE in vivo and the bioactivities of REE combined with biomacromolicullars.Due to the recent studies of the REE complexes, the ligands are nearly all monosaccharide and their ramifications. To find richer and more stable ligands is getting to be a hot topic. There are plenty of organic substances in the waste liquids after extracting mannitol or sodium alginate from Laminaria; the outgrowth of processing tea polyphenols from coarse tea contains the tea polysaccharides and other substance. There are rich O, S, N, H, C, and P, in organic substance of the wasteliquids and tea polysaccharides, and can be a good and cheap source of ligands to be coordinated with REE and can be exploited to make various REE complexes with more capabilities.The paper shows that the polysaccharides could coordinate with Ce(NH4)2(NO3)6 or REE to prepare the complexes. We notarize the makeup of the complexes through the UV spectra and the fluorescent emission spectra. Then we research the degradation of phosphodiester bond in pNPP and organophosphorus pesticides. The results show that the complexes had efficient hydrolysis effect for pNPP and organophosphorus pesticides. Ce-Dex and Ce-Lam completed the hydrolysis of pNPP in 30-40 minutes. Compared with the self-degradation of chloropyrifos, the complexes can obviously promote the degradation of chloropyrifos at 25 °C and pH7.0 and the pesticide is almost degraded completely after 48h. We applied the complexes to the agricultural production and found that the complexes could promote the production of crops; and that the complexes could remarkably degrade the organophosphorus pesticides in the production of the no-social-effects-of-pollution vegetables and improve the quality of spanich and tea as biologic function fertilizer. The complexes also could obviously reduce the organophosphorus pesticides residual in the gingengs and improve the sanitation conditions of rare medicinal materials as the washing preparation.It is well known that the esterases have all-important functions in the degradation of organophosphorus pesticides. The data of the examination indicate that the same esterase can hydrolyze different organophosphorous compounds, carbamate and carboxyl acid esters in some instances. And the same complex can hydrolyze pNPP and different organophosphorous pesticides. So in a sense the complex is a sort of mimic hydrolase.The study of the hydrolysis of polysaccharides and their complexes will stimulate the highly-valued utilization of rich resources; improve the production and quality of the crop and also offer significative reference to produce the no-social-effects-of-pollution food.