Analytical importance of determination of lipase activity for the express analysis of contamination by heavy metals of sunflower seeds

During the last decades becoming more sharply there is a problem of chemical and environmental monitoring and industrial inspection the content of toxic elements in food raw materials and foodstuff. At the same time there is a need to develop rapid methods, informative, integral, reflecting not only the safety but also the ecological purity of food raw materials. The method of determination of content of toxic elements on activity of its own lipase of in situ (AОL-method) in seeds of oil-bearing crops, on the example of sunflower is offered. The system of mathematical assessment of analytical criteria of laboratory test used in clinical laboratory diagnostics was for this purpose adapted. Sunflower seeds in which established the maintenance of toxiferous elements served as an object of a research: Cd, Pb, As, Hg, by atomic absorption method on the KVANT-Z.ETA device. Further tests divided on clear, including high-quality and pollution-free, and polluted - naturally containing toxiferous elements and which are artificially contaminated. Definition of activity of a lipase of seeds was carried out by the standard titrimetric method. Decrease of the activity of enzyme was connected with the maintenance of toxiferous elements. Proceeding from the received results counted an analytical significance (sensitivity, specificity, and predictive value of descriptiveness the positive and negative results) of determination of level of maintenance of toxiferous elements in sunflower seeds by the AОL-method. The set values of analytical specificity of a method and predictive value of a positive take at the level of 77.3% and 71.4% respectively, do not allow to use the offered method for the quantitative analysis, however, analytical sensitivity at the level of 86.2% and the predictive value of the negative result at the level of 89.5%, allow to recommend the AOL-method for screening programs of chemical environmental monitoring and technological monitoring of a contamination of seeds of sunflower toxiferous elements.