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High-performance liquid chromatography with diode array (LC-DAD) and electrospray ionization mass spectrometric detection (ESI-MS) was used to analyze phenolic compounds of two blackberry species ( Rubus glaucus Benth. and Rubus adenotrichus Schlech.) growing in South America. UV-visible spectrophotometry was a valuable tool for identifying the class of phenolic compound, whereas MS and MS ( n ) fragmentation data were useful for their structural characterization. Ellagitannins were the major compounds, with sanguiin H-6 and lambertianin C being the predominant ones. The anthocyanin composition as well as the presence or absence of kaempferol glycosides can be used to distinguish the Rubus species studied. Flavonol hexoside-malonates were identified in both berries. Hydroxycinnamic acids were minor compounds and found as ferulic, caffeic, and p-coumaric acid esters. Similar contents were obtained by analysis of soluble ellagitannins and ellagic acid glycosides as ellagic acid equivalents and by analysis of ellagic acid equivalents released after acid hydrolysis.

The objective of this study was to create a French database on the polyphenol content of fruit and vegetables as uncooked fruits and vegetables and then to evaluate polyphenol intake through fruit and vegetable consumption in France. To achieve this, we used the Folin-Ciocalteu method adapted to fruit and vegetable polyphenol quantitation (1). Vegetables with the highest polyphenol concentration were artichokes, parsley, and brussels sprouts [>250 mg of gallic acid equivalent (GAE)/100 g fresh edible portion (FEP)]; fruits with the highest concentrations were strawberries, lychees, and grapes (>180 mg of GAE/100 g FEP). Conversely, melons (Cantaloupe cv.) and avocados had the lowest polyphenol concentration for fruits and vegetables, respectively. Based on fruit consumption data, apples and strawberries are the main sources of polyphenols in the French diet, whereas potatoes, lettuces, and onions are the most important vegetable sources. Total polyphenol intake from fruit is about 3 times higher than from vegetables, due to the lower polyphenol concentration in vegetables. The calculation of polyphenol intake, based on both assessment methods used [(Société d'Etudes de la Communication, Distribution et Publicité (SECODIP) and Supplémentation en Vitamines et Minéraux Antioxydants (SUVIMAX)], showed that apples and potatoes provide approximatively half of the total polyphenol intake from fruit and vegetables in the French diet.

Polyphenols, widely spread in our diet by the consumption of plant food products, are commonly determined using Folin-Ciocalteu reagent that interacts with other different reducing nonphenolic substances and leads to an overestimation of polyphenol content. In this paper we report an optimized Folin-Ciocalteu method to specifically determine the contents of total polyphenols and vitamin C. After the optimal conditions for the colorimetric assay were set, solid-phase extraction (Oasis HLB (hydrophilic-lipophilic balance)) was carried out to eliminate the water-soluble reducing interferences including vitamin C. Colorimetric correction was thus performed by subtracting interfering substances contained in the water washing extract from the raw extract. Moreover, vitamin C present in the water washing extract can be destroyed by heating and thus colorimetrically deduced. This procedure was set up with synthetic solutions and validated on different extracts from fruit products.

Propolis is produced by honey bees from a series of resinous, gummy and balsamic substances collected from the leaf buds of different tree species and mixed with their secretions. It is used as a sealant and antiseptic in the hive. Because of its antimicrobial properties, propolis has become a popular alternative medicine or food for health protection and disease prevention. The presence of a large number of flavonoids, aromatic acids and phenolic compounds has been suggested to be responsible for most biological and pharmacological activities of propolis. This review aims to provide a critical analysis of the different studies which evaluate the activity of propolis against fungi and to identify the chemical components responsible for such activity. The discussion of the methodological approaches used and the issued results is a key point of this review to highlight knowledge gaps. This review will first describe the chemical composition of the propolis and the factors of variability including geographical and botanical origins and then examine its antifungal activities with a focus against phytopathogenic fungi. Finally, it will discuss the main components responsible for such activities and their mechanism of action. [ABSTRACT FROM AUTHOR]

Abstract: Major compounds (i.e. phenolic compounds and carotenoids) were analysed in the extracts of the edible part of three tropical fruits: the Andean blackberry, the naranjilla and the tree tomato. Ellagitannins and anthocyanins were predominant in blackberries and phenolic composition can be used to differentiate the two species studied. Similar phenolic composition occurred in red and yellow tree tomato except for anthocyanins which were absent in the yellow tree tomato. Phenolic acids were detected in the naranjilla pulp. Carotenoids were analysed in the fruits. The composition in carotenoids was similar in the two varieties of tree tomato and their vitamin A activity was calculated. Carotenol fatty acid esters were predominant. β-Cryptoxanthin esters and β-carotene were the major carotenoids. The carotenoid content was high compared to literature data, providing an important high vitamin A activity. In blackberries and naranjilla, this class of compounds was found only at trace level. Finally, ORAC values were estimated in different solvent extracts and results were compared with published data in common fruits. [Copyright &y& Elsevier]