Fruits of 10 cultivars of muscadine grapes (five bronze skin and five purple skin) grown in southern Georgia were separated into skin, seed, and pulp. Each fruit part and the leaves from the corresponding varieties were extracted for HPLC analysis of major phenolics. Total phenolics were determined colorimetrically using Folin-Ciocalteu reagent. Total anthocyanins were determined according to a pH-differential method, using a UV-visible spectrophotometer. Antioxidant capacity was determined by the Trolox equivalent antioxidant capacity (TEAC) assay. Gallic acid, (+)-catechin, and epicatechin were the major phenolics in seeds, with average values of 6.9, 558.4, and 1299.4 mg/100 g of fresh weight (FW), respectively. In the skins, ellagic acid, myricetin, quercetin, kaempferol, and trans-resveratrol were the major phenolics, with respective average values of 16.5, 8.4, 1.8, 0.6, and 0.1 mg/100 g of FW. Contrary to previous results, ellagic acid and not resveratrol was the major phenolic in muscadine grapes. The HPLC solvent system used coupled with fluorescence detection allowed separation of ellagic acid from resveratrol and detection of resveratrol. Reported here for the first time are the phenolic content and antioxidant capacity of muscadine leaves. Major phenolics in muscadine leaves were myricetin, ellagic acid, kaempferol, quercetin, and gallic acid, with average concentrations of 157.6, 66.7, 8.9, 9.8, and 8.6, respectively. Average total phenolics were 2178.8, 374.6, 23.8, and 351.6 mg/g gallic acid equivalent in seed, skin, pulp, and leaves, respectively. Total anthocyanin contents were 2.1 and 132.1 mg/100 g of FW in the skins of bronze and purple grapes, respectively, and 4.3 and 4.6 mg/100 g of FW in seeds and pulps, in that order. Antioxidant capacity values were, on average, 2.4, 12.8, 281.3, and 236.1 microM TEAC/g of FW for pulps, skins, seeds, and leaves, respectively.

The dumping of tanneries is a severe pollution problem because it generated wastewater full of chemical and toxic substances which deteriorate the water sources and the health of organisms that are living there. The aim of this project was to determine the removal capacity of the total chromium (Cr) and chlorides (Cl-) present in the wastewater of the tanneries by the bioremediation with the Chlorella sp. and Scenedesmus sp. microalgaes, orange peels and citrus pectin. The methods applied were: i) the inoculation of a single or mixture microalgaes in the 434 Victor Alfonso Ramirez Losada et al. water of tanneries for a period of 24 or 48 hours (h), or a photoperiod 12h:12h (light:darkness); ii) orange peels with particle sizes: 0.5mm, 1.0mm and 2.0mm, were exposed to residual water during 2h, 4h or 6h with a rate of 0.5g/100mL; and iii) citrus pectin with equal parameters of those used in the orange peels. The initial concentration of residual water was Cr=352.2 mg/L and Cl-=25100 mg/L. The Scenedesmus sp. algae removed 98.63% (4.82 mg/L) of Cr and 54.18% (11500mg / L) of Cl-after 48h while the orange peel with particle size of 0.5mm and with only 2h of exposition decreased the initial concentration of Cr and Cl-in a 94% (21.1mg/L) and 59.76% (10100mg/L) respectively. Finally, the pectin at a contact time of 6h showed the highest absorption of Cr (98.23%-6.2 mg/L). Therefore, the three different tested products presented a very high efficiency in the reduction of ion concentration of Cr and Cl-and lead new and novel alternatives for the treatment of wastewater of the tannery industries.

El cultivo del tabaco se ha convertido en uno de los más importantes en Colombia, generando empleo a mano de obra calificada y no calificada. En la poscosecha del tabaco se han detectado varias problemáticas a resolver, una de ellas la concerniente al alto costo del combustible empleado en los hornos de curado. Por ello, se realizó una evaluación al intercambiador de calor tradicional tipo hornilla para determinar la eficiencia del uso del combustible. La información obtenida deja en evidencia la gran dificultad que se tiene con este sistema de transferencia de calor por convección natural para mantener temperaturas estables al interior del horno, generando condiciones ambientales que se alejan considerablemente de las previstas para este proceso, dependiendo estas variaciones, en gran medida, de la frecuencia de cargue de la hornilla, encontrándose además, que la eficiencia en el aprovechamiento de la energía entregada por el carbón es menor del 10%.

A traditional oven for curing tobacco leaves was redesigned (based on existing infrastructure); a forced-convection heat exchanger system was implemented in it which worked with coffee hulls as fuel. This oven (called a forced-convection tobacco leaf curing oven) was evaluated during the harvesting season. It was found that temperature and relative humidity inside the furnace could be controlled with this assembly during the three stages involved in curing tobacco leaves. The equipment used performed excellently when using coffee hulls as fuel, having the following approximate consumption during curing: 8.92 kilograms per hour during the yellowing stage, 17.75 kilograms per hour during the leaf drying and color fixation phase and 19.29 kilograms per hour during the stem drying stage. Comparative analysis of the ovens operating costs along with the proposed adjustments to be made to it would allow its implementation as a promising alternative in the existing tobacco chain.