The total acidity of orange juice is ordinarily determined by titrating a known volume of juice with a standard solution of NaOH, with phenolphthalein as indicator, the result beinog expressed as citric acid. This value includes all the substanees of an acidic nature in the juice that react with NaOH. It so happens, however, that in most fruits the chief substances reacting with NaOH are the or...

Valencia orange (Citrus sinensis) peel was employed in this work as raw material for the production of citric acid (CA) by solid-state fermentation (SSF) of Aspergillus niger CECT-2090 (ATCC 9142, NRRL 599) in Erlenmeyer flasks. To investigate the effects of the main operating variables, the inoculum concentration was varied in the range 0.5·10(3) to 0.7·10(8) spores/g dry orange peel, the bed ...

Agent Orange is at the core of an ongoing controversy involving veterans organizations that want the Federal govenment to complete a study intended to examine possible lasting health effects of exposure to this herbicide during the Vietnam War. Many Vietnam veterans are quite concerned that various health problems they have suffered may be associated with exposure to Agent Orange in Vietnam. Th...

A model solution of orange juice was prepared and stored. Factors affecting browning and formation of such decomposition products as 3-hydroxy-2-pyrone (3OH2P), 5-hydroxymethylfurfural (HMF), furfural, 5-hydroxymaltol, and 2-furoic acid were examined. Ascorbic acid (AsA) was essential for browning, which was stimulated by amino acids and citric acid, and repressed by chelators and radical scave...

BACKGROUND Decolorization of hazardous synthetic dyes using laccases in both free and immobilized form has gained attention during the last decades. The present study was designed to prepare immobilized laccase (purified from Paraconiothyrium variabile) on porous silica beads followed by evaluation of both free and immobilized laccases for decolorization of two synthetic dyes of Acid Blue 25 an...

Phenolic compounds of unripe and ripe sweet orange peels were determined using a high-performance liquid chromatography separation method with diode array detector (HPLC-DAD). The in vitro antioxidant properties and the EC50 (concentration required to obtain a 50% antioxidant effect) values were also determined. The predominant phenolic compounds were quercitrin, rutin, and quercetin with value...

Approximately 6% of dog platelets are positive for staining with thiazole orange, a dye frequently used to stain ribonucleic acid. In this report, thiazole-orange positivity is shown to mark platelets that are less than 24 hours old. Dog platelets were derivatized in vivo with N-hydroxysuccinimido biotin such that greater than 95% of all platelets were biotinylated. Newly synthesized, nonbiotin...

Our objective was to examine the effect of orange juice and hesperetin on serum total antioxidant capacity (TAC), lipid peroxidation (MDA), uric acid and hepatic xanthine oxidase (XO) and xanthine dehydrogenase (XDH) activity in hyperuricemic rats. Experimentally hyperuricemia in rats was induced by intraperitoneal injection of potassium oxonate (250 mg/kg). Orange juice (5 ml/kg) and hespereti...

BACKGROUND Consumption of fruit and vegetables is associated with improved health and a decreased prevalence of chronic degenerative processes. OBJECTIVES The objectives were to assess the bioavailability of vitamin C from orange juice and its influence on plasma vitamin C and 8-epi-prostaglandin F(2 alpha) (8-epi-PGF(2 alpha)) concentrations in a healthy human population. DESIGN Six men an...