Wild Mediterranean plants as traditional food: a valuable source of antioxidants.

Some wild Mediterranean plants used as traditional food are an extraordinary source of antioxidants. We tested some properties of 10 of these herbaceous plants, used in Liguria (Northwest Italy) to prepare a traditional dish known as "prebuggiun." A total of 9 of them were found to have a polyphenol content and antioxidant properties similar or better than those of red chicory and blueberry, which are, in the case of vegetables and fruits, among the richest of antioxidants. Practical Application: In this article, we reported a study on wild plants growing in the Mediterranean area. These herbs have been neglected and this study aimed to revalue these plants because they are an extraordinary source of antioxidants. The increasing demand for natural antioxidants (additives in the food industry too) justifies the search for new sources of natural antioxidants. The revaluation of these plants will be interesting for: (1) consumer health, rediscovering a vegetable source of high antioxidant power; (2) possibility of producing new commercial products, such as food supplements of high quality and low cost; (3) pharmacological applications.

Fast and simple method for the simultaneous evaluation of the capacity and efficiency of food antioxidants in trapping peroxyl radicals in an intestinal model system.

A simple oxygraphic method, for which the theoretical and experimental bases have been recently revised, has been successfully applied to evaluate the peroxyl radical chain-breaking characteristics of some typical food antioxidants in micelle systems, among which is a system that reproduces conditions present in the upper part of the digestive tract, where the absorption and digestion of lipids occur. This method permits one to obtain from a single experimental run the peroxyl radical trapping capacity (PRTC, that is, the number of moles of peroxyl radicals trapped by a given amount of food), the peroxyl radical trapping efficiency (PRTE, that is, the reciprocal of the amount of food that reduces to half the steady-state concentration of peroxyl radicals), and the half-life of the antioxidant ( t(1/2)) when only a small fraction of peroxyl radicals reacts with the antioxidants present in foods. Examples of application of the method to various types of foodstuffs have been reported, assessing the general validity of the method in the simple and fast evaluation of the above-reported fundamental antioxidant characteristics of foods.

A method to evaluate capacity and efficiency of water soluble antioxidants as peroxyl radical scavengers.

In this paper, we report on a method to evaluate the activity of water soluble and H-atom donor antioxidants as peroxyl radical scavengers in a micelle system reproducing the conditions occurring in the upper small intestine in humans, during digestion and absorption of lipids. This method, which overcomes some of the problems of the total radical trapping antioxidant parameter (TRAP) assays, measures the peroxyl radical trapping capacity (n) and the peroxyl radical trapping efficiency IC50(-1) of antioxidants, that is the number "n" of peroxyl radicals trapped by one molecule of the studied antioxidant and the reciprocal of the antioxidant concentration that halves the steady-state concentration of peroxyl radicals, respectively. These two fundamental parameters characterizing the radical chain breaking of many water soluble antioxidants, among which dietary polyphenols, can be obtained with relatively good precision from a single experiment, on the basis of a rigorous treatment of the kinetic data.

Localization of a putative ClC chloride channel in spinach chloroplasts.

Seven genes seem to encode for putative ClC chloride channels (AtClC-a to AtClC-g) in Arabidopsis thaliana. Their function and localization is still largely unknown. AtClC-f shares considerable sequence similarity with putative ClC channel proteins from Synechocystis, considered to represent the precursor of chloroplasts. We show by biochemical and mass spectrometry analysis that ClC-f is located in the outer envelope membrane of spinach chloroplasts. Consistent with the plastidial localization of ClC-f, p-chlorophenoxy-acetic acid (CPA) reduces photosynthetic activity and the protein is expressed in etioplasts and chloroplasts but not in root tissue. These findings may represent a step toward the molecular identification of ion channel activities in chloroplast membranes.