Lectures L 12 . 1 Physico - chemical methods of analysis of bioactive food compound

Bioactive natural products are those chemical compounds produced by living organisms that exert a biological effect on other organisms. This includes therapeutic activity for humans and animals, and well-being and in contrary toxic activity for human and animal. Variation in content of bioactive components depends upon both genetics and environment, including growing conditions, harvest and storage, processing and storage. There is a need for improving extraction efficiency and to address complexity in the phenolic compounds profile to obtain the optimum antioxidant efficiency and to deal with possible effects of food processing on the overall antioxidant potential of foods, losses and formation of naturally occurring antioxidants activity, interactions among different compounds (e.g. lipids and natural antioxidants, lipids and Maillard reaction products). At last but not least how different compounds bioactivity is manifested in living organism, in target tissues, cells etc. Consequently, a high demand exists for novel and efficient screening technologies, which enable successful incorporation of natural products in food chain. Over recent years several techniques have been developed, which interfaced continuous-flow biochemical detection, biochromatography with a range of analytical instruments, such as LC, DAD, UV and MS. Reversed phase HPLC is recognized as the most broadly applicable of bonded phases for this purpose and when interfaced with a diode array detector (DAD) and especially with mass spectrometry. On the other hand for volatile flavor and odor compounds; toxic and anti-toxic compounds in food gas chromatography, or comprehensive chromatography combined with mass spectrometry are techniques of choice. New emerging techniques are multidimensional combinations of gas chromatography (GC) and liquid chromatography combined with MS and/ or NMR and/or IR. Efficient methods of separation from matrix and clean-up are elaborated, thus providing the tools for identification, quantitation and quality control of bioactive ingredients in food products. L12.2