The contents of antioxidant nutritional compounds, total soluble phenolics (TSP), vitamin C, vitamin E, beta-carotene, and total carotenoids (TC), were correlated with the total antioxidant capacity (AOC) of hydrophilic (HPE) and lipophilic extracts (LPE) from eight horticultural crops, namely, guava, avocado, black sapote, mango, papaya, prickly pear fruit, cladodes, and strawberry. AOC was measured using six different assays: 2,2'-diphenyl-1-picrylhydrazyl (DPPH), N,N-dimethyl-p-phenylendiamine (DMPD), ferric-ion-reducing antioxidant power (FRAP), oxygen radical absorbance capacity (ORAC), Trolox equivalent antioxidant capacity (TEAC), and total oxidant scavenging capacity (TOSC). AOC values from HPE were about 95 times higher than LPE values. HPE of guava had the highest AOC value when evaluated with DMPD, DPPH, FRAP, TEAC, and TOSC assays, whereas with ORAC assay, black sapote had the highest value. HPE of papaya and prickly pear fruit presented the lowest AOC values with all assays. From HPE, vitamin C and TSP contents were highly correlated with AOC for all assays, while from LPE, TC and beta-carotene contents possessed a high correlation with AOC only in the DMPD assay.

Mangofruit has a relatively short storage life of about 2 to 3 weeks at 13C. In order to prolong the storage life of 'Haden' mangoes, fruit were coated with 3 concentrations (8,16 and 24 g.L-9 of the edible coating film "Sempefiesh " and then stored at 13C and 85% RH. Fruit were then evaluated every 4 days for up to 32 days for total soluble solidr (TSS), titratable acidity (TA), pH, firmness, weight loss, color of the skin, and ascorbic acid content. All 3 concentrations applied to the h i t affected j u i t ripening. TA, jirmness, and green color were higher in coated juit, and weight loss, SST, and pH were lower compared with the noncoatedBit. 'Sempei@esh'' had no efect on decay development. Ascorbic acid decreased in all storedfruit, but this decrease was slower in coatedjuit, and there were no significant differences between the different "Semper$-esh " concentrations.

A single copy of the N-acetyl-L-glutamate synthase gene (SlNAGS1) has been isolated from tomato. The deduced amino acid sequence consists of 604 amino acids and shows a high level of similarity to the predicted Arabidopsis NAGS1 and NAGS2 proteins. Furthermore, the N-terminus ArgB domain and the C-terminus ArgA domain found in SlNAGS1 are similar to the structural arrangements that have been reported for other predicted NAGS proteins. SlNAGS1 was expressed at high levels in all aerial organs, and at basic levels in seeds, whereas it was not detected at all in roots. SlNAGS1 transcript accumulation was noticed transiently in tomato fruit at the red-fruit stage. In addition, an increase of SlNAGS1 transcripts was detected in mature green tomato fruit within the first hour of exposure to low oxygen concentrations. Transgenic Arabidopsis plants have been generated expressing the SlNAGS1 gene under the control of the cauliflower mosaic virus (CaMV) 35S promoter. Three homozygous transgenic lines expressing the transgene (lines 1-7, 3-8, and 6-5) were evaluated further. All three transgenic lines showed a significant accumulation of ornithine in the leaves with line 3-8 exhibiting the highest concentration. The same lines demonstrated higher germination ability compared to wild-type (WT) plants when subjected to 250 mM NaCl. Similarly, mature plants of all three transgenic lines displayed a higher tolerance to salt and drought stress compared to WT plants. Under most experimental conditions, transgenic line 3-8 performed best, while the responses obtained from lines 1-7 and 6-5 depended on the applied stimulus. To our knowledge, this is the first plant NAGS gene to be isolated, characterized, and genetically modified.

Biochemical and nutritional changes were studied during the ripening process of three Opuntia morphospecies with different ripening behavior: Naranjona (O. ficus-indica), Blanca Cristalina (Opuntia sp.), and Esmeralda (Opuntia sp.) of early, early-intermediate, and intermediate-late ripening, respectively. In loss of fresh weight, Naranjona showed the highest values, while in Blanca Cristalina and Esmeralda, a discrete weight loss was found. No significant differences were found among morphospecies in soluble solids, total titratable acidity and pH during the postharvest days. Blanca Cristalina and Esmeralda showed an increase in the content of carotenoids, while these diminished in Naranjona. The cell wall enzymes evaluated showed particular behaviors during the ripening of each morphospecies suggesting a fine biochemical control and not a clear relationship between fruit softening and enzyme activity. This study provides basic information on prickly pear ripening, in order to understand this process for its control and for improving shelf life.

Starch is an attractive raw material as ingredient for edible film manufacture because of its low cost, abundant availability, renewability, and biodegradability. Nevertheless, starch based films exhibit several disadvantages such as brittleness and poor mechanical and barrier properties, which restrict its application for food packaging. The use of the extrusion technology as a pretreatment of the casting technique to change the starch structure in order to obtain edible films, may constitute an alternative to generate coatings with good functional properties and maintain longer the postharvest quality and shelf life of fruits. For this reason, the objective of this study was to optimize the conditions of an extrusion process to obtain a formulation of modified starch to elaborate edible films with good functional properties using the casting technique and assess the effect during the storage when applied on a model fruit. The best conditions of the extrusion process and concentration of plasticizers were obtained using response surface methodology. From optimization study, it was found that appropriate conditions to obtain starch edible films with the best mechanical and barrier properties were an extrusion temperature of 100 °C and a screw speed of 120 rpm, while the glycerol content was 16.73%. Also, once applied in fruit, the loss of quality attributes was diminished.

Extrusion technology is widely used for the production of breakfast cereals (BC). In order to improve their nutritional/nutraceutical quality, the addition of citrus fruit pomace rich in bioactive compounds has been suggested. The objective of this work was to study the effect of extrusion temperature (ET, 88.79-131.21°C) and dehydrated naranjita pomace content (DNP, 0.64-13.36%) on physicochemical, nutritional and antioxidant properties of BC. For statistical analysis, the response surface methodology was used. When ET was elevated, the bulk density, breaking stress, color b* and soluble dietary fiber increased, whereas when DNP was higher, the water solubility index, color b*, soluble dietary fiber, total phenolic compounds, and antioxidant activity increased. The extrusion process decreased the β-glucans content compared to a non-extruded control. These findings indicated that it is possible to produce BC with acceptable physicochemical, nutritional and antioxidant characteristics by adding DNP, whose consumption presents potential benefits in human health. Efecto de la extrusión sobre propiedades fisicoquímicas, nutricionales y antioxidantes de cereales para desayuno producidos a partir de salvado y subproductos de naranjita deshidratados RESUMEN La tecnología de extrusión es utilizada ampliamente para la producción de cereales para desayuno (CPD). Con el fin de mejorar su calidad nutricional/nutracéutica, se ha sugerido la adición de subproductos de frutos cítricos ricos en compuestos bioactivos. El objetivo de este trabajo fue estudiar el efecto de la temperatura de extrusión (TE, 88.79-131.21°C) y del contenido de subproductos de naranjita deshidratados (SND, 0.64-13.36%) sobre las propiedades fisicoquímicas, nutricionales y antioxidantes de CPD. Para el análisis estadístico, se utilizó la metodología de superficie de respuesta. Cuando se incrementó TE, aumentaron la densidad aparente, resistencia a la ruptura, color b* y fibra dietaria soluble, mientras que cuando se incrementó DNP, aumentaron el índice de solubilidad en agua, color b*, fibra dietaria soluble, compuestos fenólicos totales y actividad antioxidante. El proceso de extrusión disminuyó el contenido de β-glucanos en comparación con un control no extrudido. Estos hallazgos indican que es posible producir CPD con aceptables características fisicoquímicas, nutricionales y antioxidantes mediante la adición de SND, cuyo consumo tiene beneficios potenciales en la salud humana.

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