Protective activity of water soluble components of some common diet vegetables on rat liver microsome and the effect of thermal treatment

The water soluble antioxidant properties of carrot, cauliflower, celery, eggplant, mushroom, garlic, onio, white cabbage, white potato, tomato, yellow bell pepper, and zucchini were investigated. Vegetable juices were obtained by centrifugation, and each antioxidant properties was determined in terms of the protective activity (PA%) against rat liver microsome lipid peroxidation induced by CCl4 and measured by mlaondialdehyde release. All juices were found to be active. PA was very high and constant for mushroom, garlic, cauliflower, and potato. For white cabbage, zucchini, and eggplant the PA reached similar values, but was less constant. Onion and yellow bell pepper showed high PA which was more variable, and the PA for tomato and celery was less high and very variable, especially in the case of carrot juice.The juices were also analysed after different technological treatments (boiling, freezing, and freeze-drying). In general boiling and freezing juices resulted in a slightly decreased PA while freeze-drying slighlty increased their PA values. Custer analysis was carried out considering the PA values of teh various treated juices and their relative RSD values and permitted us to subdivided the vegetables according to their behavior. Juice components were separated according to their polarity on a Baker C18 cartridge. Buond and unbound fractions obtained from each vegetable juice were shown to be protective against lipid peroxidation with the exception of the bound yellow bell pepper fraction. The results pointed out different interactions between the vegetable juice components.