The Studies On Preparation And Properties Of Wheat Gluten Edible Films

Zearalenone (ZEN) is one of the main fungal toxin that contaminate grains and edible oil, of which has been established strict limitation standards by multiple countries including China. ZEN is the secondary metabolite of fusarium in specific conditions. ZEN leads to serious healt h risks to human, and financial looses of China’s livestock breeding. Utilizing the contaminated grains and edible oil reasonably and safely has became the urgent task of reducing the pollutio n of ZEN. The objective of this research is to explore a solution to degrade the toxin. This resea rch mainly works on screening and analyzing the mechanism of degradation, which is briefly o utlined as follow:The efficient screening methods of degrading ZEN stains were established based on th e previous work, which mainly included three method:1) screening and culturing the strains in basal salts medium by utilizing ZEN as the sole carbon source;2) utilizing LB as the basic med ium and adding ZEN strains for co-culturing, and3) enrichment culturing and screening of the dilute samples in basal salts medium by utilizing ZEN as the sole carbon source. Through the e nrichment culturing and purification, nine degradable ZEN stains were obtained in this researc h where three of the strains had better degradation effect. The preliminary identification of thes e three strains was made according to the physiological, biochemical and morphological charac ters. By completing the16s rRNA sequencing and the cluster analysis, a ulterior identification was then applied to these three strains and found that two of them were Bacillaceae. They wer e named as Y64-3, Y84-7and ASAG7respectively. After further stabilization and and experim ent, it turned out that the degradation rates of these three strains were60.08%,54.90%and99%.The research of the physiological characters and the degradation features of degradable str ains clarified the curve for strain growing with time, and the optimal growing temperature was28℃when ASAG7was culturing in the LB basic medium, as well as the degradation ability c hanging with time. It also proved that the strains degraded the ZEN by secreting degradation en zyme extracellularly. Three time-degradation rate diagrams which described the elimination eff ect of the three strains to ZEN were generated, and the fermentation medium which can enable the ASAG7massively produce the enzyme to degrade ZEN was also determined.Through preliminarily analyzing the mechanisms to degrade the ZEN of Y64-3and Y84-7, the mass spectrum indicated that these two strains generated new degradable substances during the degradation process to ZEN. And the degradation mechanism of ASAG7was analyzed by using two stage mass spectrometry, and concluded preliminarily. The obtainment of these strains and the analysis results of the degradation mechanisms would help clone encoding genes of related degradation and provide favorable materials for application...