非金属矿物材料脱霉性能评价方法研究进展

Evaluation Method of Non-metallic Mineral Materials for Mycotoxins Removal: a Review

饲料极易霉变产生霉菌毒素,不但危害动物机体健康,还会引发食品安全问题。蒙脱石、凹凸棒石、海泡石及沸石等非金属矿物材料具有天然的层状、纤维状及孔状纳米结构,矿物表面含有丰富的羟基和悬挂键,晶体结构比较稳定,具有良好的吸附性能和离子交换能力,在饲料脱霉领域的应用前景十分广阔。添加到饲料中的脱霉材料可能会与动物体内的营养物质、抗生素、微量元素等相互作用;另外,饲料内会同时含有多种霉菌毒素,不同霉菌毒素间会产生协同作用。因此,脱霉材料对饲料内不同霉菌毒素的脱除效果有很大差异。目前国内外尚且没有统一的非金属矿物材料脱霉性能的检验方法和评价标准,主要原因在于标准溶液中霉菌毒素的浓度及脱霉材料的添加浓度有很大差异,不易统一。市场上脱霉产品良莠不齐,脱霉效果又不容易直观评价,不仅给用户的选择带来很大困扰,还给畜牧业的发展带来了极大影响,因此建立科学统一的非金属矿物材料脱霉性能检测实验方法和评价标准势在必行。脱霉材料性能检测实验方法主要分为体外实验法、体内实验法及体外模拟实验法。其中,体外实验方法简单、快捷,易于实现,应用广泛,但缺少动物消化吸收环境,不能准确评定脱霉材料对霉菌毒素的实际吸附效果,但可判断脱霉材料对霉菌毒素的吸附是否有效。体内实验虽然可以准确评价脱霉材料的有效性和安全性,但动物体内消化吸收过程复杂,实验过程所需周期较长,工作量大,样品的采集和制备比较困难。随着对动物消化吸收过程研究的深入,可建立体外模拟生物消化系统来对脱霉材料进行检测、评价,其结果更接近动物体内脱霉材料与霉菌毒素的结合,但建立体外模型复杂,难度较大,设备购买昂贵。因此,在体外模拟酶消化法和体外实验吸附-解吸法的基础上提出一种新的体外模拟实验法来对非金属矿物材料的脱霉性能进行测定。本文介绍了典型非金属矿物材料脱霉性能的主要检测实验方法、研究进展及发展方向,以期为非金属矿物材料脱霉性能检测及评价方法标准化奠定基础。

Animal feed is easily contaminated by mycotoxins,which will cause severe threat to animal and human health.Non-metallic mineral materials,such as montmorillonite,attapulgite,sepiolite and zeolite,have natural layered,fibrous and poreous nanostructures.Moreover,abundant hydroxyl and dangling bonds at the surface of the non-metallic mineral materials are usually accessible to contaminant,acting as adsorption sites,and the relatively stable crystal structure possess high ion exchangeable capacity.These characteristics make it a powerful adsorbent for contaminant,which has broad application prospects to remove mycotoxins.However,there exist some difficulties for evaluation method of non-metallic mineral materials to remove mycotoxins.For example,mycotoxins removal material may interact with nutrients,antibiotics,trace elements,etc.in the body of animals.Moreover,various mycotoxins may occur simultaneously in animal feeds,and the toxic effects may be amplified due to their synergistic interaction.Therefore,the mycotoxins removal capacity of material is rather different.So far,there was no uniform test method and evaluation standard for the non-metallic mineral materials to remove mycotoxins.The main restrict of the evaluation method on the adsorption capacity is that the diversity of mycotoxins and their variety concentration in the feed.Furthermore,the diverse,vary and complicated removal product caused great trouble to choose,which seriously hampered the healthy development of livestock and feed industries.Therefore,it is imperative to establish a scientific,effective and unified test method and evaluation standard of non-metallic mineral materials for mycotoxins removal.At present,in vitro,vivo and vitro simulation methods were widely used to test the properties of mycotoxin removal materials.All these methods are effective to a certain degree,but they still have considerable limitations in practical applications.For instance,in vitro method is simple,fast and easy to implement.However,it lacked similar animal digestion and absorption environment that limit accurate evaluation of the remove capacity.In vivo method can accurately evaluate the effectiveness and safety of mycotoxin removal materials.Nevertheless,the process of digestion and absorption in the body of animal was complicated,the experimental process was time-consuming,and the collection of the sample was extremely difficult.With the deepening of research on the digestion and absorption process of animals,an in vitro simulated biological digestion system can be established to detect and evaluate the mycotoxin removal materials.However,the establishment of in vitro simulation model was complicated and the equipment was expensive.Therefore,a novel in vitro simulation method for determining the mycotoxin removal performance of non-metallic mineral materials was proposed,which is on the basis of in vitro simulated enzymatic digestion method and in vitro experimental adsorption-desorption method.This paper reviewed the latest research progress on test methods and development direction of the mycotoxins removal performance of typical non-metallic mineral materials.It is expected that this review can provide a certain reference for the standardization of evaluation methods for non-metallic mineral materials to remove mycotoxins in animal feed.