Search results for "ascorbic acid"
showing 10 items of 295 documents
Non-Classical Transformation of Benzendiazonium Hydrogen Sulfates. Access to 1,3-Dimethylisochromeno[4,3-c]pyrazol-5(1H)-one, a Potential Benzodiazep…
2013
The compound 2-((1,3-dimethyl-1H-pyrazol-5-yl)(methyl)carbamoyl)benzene-diazonium hydrogen sulfate (10) was reacted with copper sulfate and sodium chloride, in the presence of ascorbic acid as reducing agent, to afford a mixture of the chlorinated epimers 4′-chloro-2,2′,5′-trimethyl-2′,4′-dihydrospiro[isoindoline-1,3′-pyrazol]-3-one (18) and (19), the epimers 4′-hydroxy-2,2′,5′-trimethyl-2′,4′-dihydrospiro[isoindoline-1,3′-pyrazol]-3-one (20) and (21), and N-(1,3-dimethyl-1H-pyrazol-5-yl)benzamide (22). Under the foregoing conditions, diazonium salt 10 affords neither the 2-chloro-N-(1,3-dimethyl-1H-pyrazol-5-yl)-N-methylbenzamide (23) nor the tricyclic derivative 24, the classical products…
Determination of liposoluble vitamins in cooked meals, milk and milk products by liquid chromatography
2002
A method for the simultaneous determination of liposoluble vitamins in cooked meals was established. Saponification was performed with 50% (w/v) KOH at 80 degrees C, and ascorbic acid was added as antioxidant. The subsequent extraction was carried out with diethyl ether. This was followed by a liquid chromatographic separation on a reversed-phase C18 column with methanol-water (94:6, v/v as the mobile phase. Retinyl acetate was used as the internal standard. The analytical parameters linearity, detection limit (0.19 and 8.33 microg/100 g for retinol and alpha-tocopherol, respectively), precision of the method (RSD=5.24 and 6.99% for retinol and alpha-tocopherol, respectively) and recovery a…
Red wine extract prevents neuronal apoptosis in vitro and reduces mortality of transgenic mice.
2007
In this work, we have investigated the effects of nutritional antioxidants as antidegenerative agents on glutamate-induced apoptosis in primary cultures of cerebellar granule neurons (CGNs). Glutamate-induced apoptosis is also associated with intracellular [Ca(2+)]i overload, generation of reactive oxygen species (ROS), depression of cell energy metabolism, cytochrome c release, and increase in caspase-3 activity. Pretreatment (3 h) with red wine extract (5 microg/mL) and ascorbic acid (30 microM) blocks glutamate-induced apoptosis in CGNs. In vivo experiments carried out on transgenic mice expressing the human mutated Cu, Zn superoxide dismutase (SOD1) G93A (mSOD1(G93A)) show that mice fed…
EFFECT OF PASSIVE ATMOSPHERE AND CHEMICAL TREATMENT ON FRESH CUT OF WHITE-FLESH PEACH CULTIVAR 'SETTEMBRINA DI BIVONA'
2015
Peach germplasm in Italy includes white- and yellow-flesh peaches, all of them characterized by a persistent aroma and an excellent flavor. However, their behavior, in terms of postharvest maintenance and suitability for minimal processing, has never been investigated. The aim of this study was to investigate the effects of passive atmosphere and chemical treatment, with 2% ascorbic acid and 1% calcium lactate, in order to prevent fruit browning and to maintain the quality of fresh cut slices of the white-flesh peach cultivar ‘Settembrina di Bivona’. To achieve a passive atmosphere condition, approximately 150 g of peach fruit slices were placed in rigid bi-oriented polystyrene bags and sto…
EFFECT OF FRUIT-SET TIME ON THE QUALITY PERFORMANCE OF ANNONA CHERIMOLA MILL. FRUIT
2019
The aim of this work was to analyze the differences between fruits obtained by different dates of fruit set and identify the proper fruit-set time that allows to obtain the optimum fruit quality in Annona cherimola cv Fino de Jete, planted in Southern Italy. Six fruit-set dates were selected from the first week of June to the second week of July. Fruits were sampled from October to November, when 1500 Growing Degree Days (DD) were accumulated; The DD were calculated using a base temperature of 12 °C. Fruit fresh weight (FW) and skin colour were measured. These parameters were measured also after storage, and in addition, the following parameters were measured: fruit shape (FS), pulp colour,…
CHANGES IN ASCORBIC ACID CONTENT IN FRESH CUT SICILIAN YELLOW-FLESH PEACHES
2015
The traditional yellow-flesh peach cultivars 'Settembrina' and 'Ottobrina' di Leonforte ripen respectively during the first 10 days of September, and the first 10 days of November, in Sicily, Italy. During pit hardening, fruit are covered with a paper bag in order to protect them from Mediterranean fruit fly. To understand their behaviour in terms of postharvest maintenance and suitability for minimal processing, 'Settembrina' and 'Ottobrina' di Leonforte were processed (i.e., cleaned, washed, peeled, cut, dipped and packed) to obtain fresh-cut peaches. Fresh cut slices were stored in perforated or bi-oriented polystyrene bags, after soaking in either a 2% ascorbic acid and 1% calcium lacta…
Quality changes in fresh-cut mango cubes submitted to different gas partial pressure of active MAPs
2018
The study was performed to assess chemical-physical and sensory quality changes in 4±1°C stored fresh-cut mangos and to test the effect of active modified atmosphere packaging (MAP) with different gas partial pressures. Sicilian fruits of ‘Keitt’ mango (Mangifera indica L.) were immerged in hydrogen peroxide (H2O2) after being peeled. Next, the flesh was cut in cubes and dipped in citric acid (0.5%, w/v) and ascorbic acid (0.5%, w/v). Treated fruits were placed in a non-perforated high density polyethylene package flushing different gas mixtures and kept at 4°C for 21 days. We used four different gas partial pressures: a) 60 kPa N2, 30 kPa CO2 and 10 kPa O2; b) 30 kPa CO2 and 70 kPa N2; c) …
Use of xanthan gum as edible coating to prolong shelf life of cactus pear fruit
2022
The objective of this work was to elucidate the effect of xanthan gum-based edible coating C35H49O29 on the quality of cactus pear fruit (Opuntia ficus-indica). The research was conducted in 2018, on O. ficus-indica ‘Bianca’ fruit, coming from second bloom “scozzolatura”. After harvest, 100 fruits were coated with a xantan gum (XAN) and distilled water and on other 100 fruits were immersed in distilled water (CTR). All fruits were stored at 6±0.5°C with RH 90% for 30 days. Every 7 days, visual quality browning index score, flesh colour, total soluble solids (TSS), total acidity (TA), ascorbic acid and total phenols were measured. During cold storage, fruit treated with XAN (p<0.05) showe…
Effect of passive atmosphere and chemical treatment on fresh cut of white flesh peach cultivar Settembrina di Bivona
2013
Effect of Opuntia ficus-indica Mill. mucilage edible coating on quality of fresh-cut cactus pears during cold storage
2022
Cactus pear [(Opuntia ficus-indica (L.) Mill.] consumption and marketability are limited by the presence of spines and glochids on the fruit surface. Minimally processed cactus pear fruits are characterized by a short shelf life due to the peel removing that increases tissue senescence and deterioration. The aim of this study was to evaluate the effect of O. ficus-indica (OFI) mucilage edible coating on quality, nutraceutical, and sensorial parameters of minimally processed cactus pear. OFI fruits were collected in mid-October and were quickly moved to the nearby laboratory. One-year-old cladodes were sanitized, sliced into squares, and cooked in a microwave oven and mixed using a homogeniz…