Covering: the literature from 1998 to 2004 The aim of the present review is to summarise the knowledge about newly isolated acetogenins (ACGs) in the last six years. It will also report the total syntheses that have allowed either the confirmation or the revision of some structures, together with the biological activities and mechanism of action of such interesting natural products. In fact, of the 417 isolated compounds reviewed, over 176 have been added during the period from 1998 to 2004.

The main objective of this study was to compare the performance of two liquid organic fertilizers, an animal and a plant-based fertilizer, with mineral fertilization on citrus trees. The source of the fertilizer (mineral or organic) had significant effect in the nutritional status of the organic and conventionally managed mandarins. Nutrient uptake, vegetative growth, carbohydrate synthesis and soil characteristics were analyzed. Results showed that plants fertilized with animal based liquid fertilizers exhibited higher total biomass with a more profuse development of new developing organs (leaves and fibrous roots). Liquid organic fertilization resulted in an increased uptake of macro and micronutrients compared to mineral fertilized trees. Moreover, organic fertilization positively affected the carbohydrate content (fructose, glucose and sucrose) mainly in summer flush leaves. Liquid organic fertilization also resulted in an increase of soil organic matter content. Animal-based fertilizer, due to intrinsic composition, increased total tree biomass and carbohydrate leaves content, and led to lower soil nitrate concentration and higher P and Mg exchangeable in soil extract compared to vegetal-based fertilizer. Therefore, liquid organic fertilizers could be used as an alternative to traditional mineral fertilization in drip irrigated citrus trees.

Chemical content in peels of fruits belonging to cultivars of Clementine mandarin (Fino, Loretina and Marisol), Satsume mandarin (Owari), Navel orange (Navelate and Navelina) and Common orange (Valencia Late) groups have been analyzed. The influence of the variety on the content of bioactive constituents at the varietal level is discussed. Rind contents showed similar tendencies for the majority of compounds although Satsume group presented the highest amounts on the flavanone glycosides hesperidin and narirutin, as well as the highest amounts of the carotenoid and β-cryptoxanthin, comparing with the remaining varieties studied. Both mandarin and orange varieties studied showed similar tendencies concerning to other phenolic compounds and total ascorbic acid concentrations. Limonene was the most abundant peel essential oil in all cultivars studied, followed by myrcene. Calcium and potassium were the dominant macronutrients for each cultivar studied, although the proportion of the individual nutrients ranged among different cultivars.