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Total Phenolic Compounds (total + phenolic_compound)
Selected AbstractsStorage stability of a high dietary fibre powder from orange by-productsINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 4 2009Juana Fernández-López Summary The goal of this investigation was to evaluate the effects of storage time and conditions on the physicochemical and microbiological properties of a high dietary fibre powder (HDFP). HDFP for this study was manufactured from orange juice industry by-products. The storage period was 11 months and samples were stored under vacuum or air exposure and under dark or light exposure. The HDFP is a stable product (based on chemical, microbiological and physicochemical properties) with large amounts of dietary fibre (71.62 ± 0.24 g 100 g,1 dry sample) and polyphenols content (40.67 ± 0.45 mg g,1 dry sample). Hesperidin is the major compound identified in HDFP (higher than 50% of total phenolic compounds). The packaging material used protects the HDFP only up to 6 months. After this time, the increase in moisture content decreases the quality of the product. The best storage conditions are packaging under vacuum and darkness. Both conditions preserve the colour of the fibres probably by means of avoiding pigment degradation. [source] STABILITY OF ANTHOCYANINS, PHENOLS AND FREE RADICAL SCAVENGING ACTIVITY THROUGH SUGAR ADDITION DURING FROZEN STORAGE OF BLACKBERRIESJOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 2009MIRELA KOPJAR ABSTRACT Influence of sugar and mixtures of sugar on color retention of two varieties of blackberries, Thornfree and Cacanska bestrna, were investigated during storage at ,18C for 12 months. After harvest, blackberries were coated with sugars (sucrose, fructose and glucose) and different sugar (sucrose + fructose + glucose, fructose + glucose, fructose + sucrose) mixtures. Anthocynin content, total phenol content and free radical scavenging activity of prepared samples were evaluated. Ratio of fruit : sugar was 1:1. The highest anthocyanin retention was in blackberry samples with glucose addition and the lowest in samples with sucrose addition, in both cultivars. Blackberry samples with sucrose addition had even lower retention than samples without sugar addition. Samples with an addition of other sugars had higher retention of anthocyanin than samples stored without sugars. PRACTICAL APPLICATION Possibility of phenols retention of blackberries due to sugar addition, during cold storage was investigated. Results showed that glucose had the most positive effect on anthocyanins retention as well as total phenolic compounds content. For that reason, certain amount of sucrose in fruit preserves can be replaced by addition of glucose, and for that reason retention of phenolic compounds can be higher and, as could be expected, more effective against oxidative stress in human body due to intake of product formulation with glucose. [source] EFFECTS OF VARIETY AND GROWTH SEASON ON THE ORGANOLEPTIC AND NUTRITIONAL QUALITY OF HYDROPONICALLY GROWN TOMATOJOURNAL OF FOOD QUALITY, Issue 1 2006MIKEL ANZA ABSTRACT The effects of variety and season on several organoleptic and nutritional quality parameters (i.e., dry weight (dw), total sugars, soluble solid compounds, titratable acidity (TA), electrical conductivity (EC), juiciness, firmness, vitamin C (vit C), total phenolic compounds, hydrophilic antioxidant capacity and minerals) of five different varieties of tomatoes (i.e., Jack, Cabrales, Jaguar, Iker and Nevada) grown in two crop cycles (spring and autumn) were studied. Each variety presented its own specific characteristics regarding the chosen parameters. Firmness, TA and EC were season dependent, whereas soluble solids content did not change between cycles. In some varieties, the dw, juiciness and total sugars were affected by climatic conditions. The total phenolic compounds and the hydrophilic antioxidant capacity were variety dependent in both cycles. By contrast, the vit C content was variety dependent only in the autumn cycle. Similarly, these latter parameters (phenolic compounds, hydrophilic antioxidant capacity and vit C) were also season dependent, showing higher values in the spring than in the autumn cycle. The effect of tomato variety and season on mineral contents is also discussed. Those tomatoes grown in the spring cycle had better quality according to the organoleptic parameters studied here as well as to a higher antioxidant capacity. The percentages of the recommended dietary allowances supplied by the studied tomatoes were not significantly affected by variety or season, despite differences in their physicochemical compositions. [source] Antioxidative Ability, Dioscorin Stability, and the Quality of Yam Chips from Various Yam Species as Affected by Processing MethodJOURNAL OF FOOD SCIENCE, Issue 2 2009Y.-M. Liu ABSTRACT:, The antioxidative ability, stability of storage protein dioscorin, and the quality of fried yam chips from different cultivars of Chinese yams influenced by various processing treatments were investigated. Total phenolic content and DPPH free radical scavenging effect were found to be the highest in Mingchien (MC) and the lowest in Keelung (KL) yam. Following processing, freeze-dried yams of all varieties showed the least decrease in total phenolic compounds and DPPH radical scavenging effect, while boiling caused the greatest decrease in both. Fresh yams of all varieties contained the highest dioscorin contents comparing with their counterparts. Boiling and deep-frying caused severe protein denaturation resulting in loss of dioscorin solubility after purification. Freeze-drying resulted in increase in protein surface hydrophobicity (So); nonetheless, it attained higher total phenol content, antioxidative capacity, and dioscorin stability of yams compared with other processing treatments. The peroxide values of all yam chips increased during the initial stage, then declined with advanced storage. Fracturability of all yam chips gradually decreased, due to the absorption of moisture, with increasing storage time. [source] The Effects of Bacillus pumilus, Isolated from Wheat Rhizosphere, on Resistance in Wheat Seedling Roots against the Take-all Fungus, Gaeumannomyces graminis var. triticiJOURNAL OF PHYTOPATHOLOGY, Issue 11-12 2007E. Sari Abstract The aim of this study was to verify that induced resistance was another mechanism through which Bacillus pumilus 7 km can suppress Gaeumannomyces graminis (Sacc.) Von Arx and Oliver var. tritici Walker (Ggt). Also, plant growth-promotion activity of B. pumilus 7 km and its effect on disease severity of take-all were evaluated. Soil was drenched with B. pumilus 7 km and disease severity, root and shoot fresh weights and root and shoot heights were evaluated. The activities of soluble peroxidase (SPOX), ionically cell wall-bound peroxidase (CWPOX), , -1,3-glucanase, , -1,4-glucanase and the contents of total phenolic compounds were also determined. The results indicated that disease severity in the bacterized roots was significantly less than the pathogen control roots. Also this isolate promoted root height, root and shoot fresh weights, compared with the healthy control plants. Wheat plants treated with B. pumilus 7 km showed increased presence of SPOX, CWPOX, , -1,3-glucanase, , -1,4-glucanase and phenolic compounds in bacterized roots challenged with the pathogen. In this treatment, maximum SPOX, , -1,3-glucanase and , -1,4-glucanase activities on day 4 and CWPOX activity on day 8 were recorded. Also, maximum total phenolic concentration on day 6 was recorded. The results suggest that the inhibitory effect of B. pumilus 7 km on the take-all may be related to its ability to enhance defense responses in the wheat roots. [source] Induced Resistance in Yali Pear (Pyrus bretschneideri Rehd.) Fruit against Infection by Penicillium expansum by Postharvest Infiltration of Acibenzolar-S-methylJOURNAL OF PHYTOPATHOLOGY, Issue 11-12 2005J. Cao Abstract The objective of the present study was to evaluate how disease resistance in Yali pear fruit (Pyrus bretschneideri Rehd.) was affected by the infiltration of acibenzolar-S-methyl (ASM) after harvest. The disease incidence and lesion area in/on the fruit inoculated with Penicillium expansum significantly (P < 0.05) decreased by the infiltration with 0.5 mm ASM, and the duration of protection conferred by ASM lasted over 15 days. ASM did not directly inhibit the mycelial growth of P. expansum in vitro. However, ASM treatment significantly enhanced activities of the main defence enzymes including peroxidase, phenylalanine ammonia-lyase and chitinase, and activities of antioxidant enzymes including superoxide dismutase and catalase in the fruit during the infection. Two kinds of second metabolites, total phenolic compounds and flavonoids, and two productions of lipid peroxidation, H2O2 and malondialdehyde, were also involved in the resistance and significantly accumulated in ASM-treated fruit in the infection. The inhibitory effect of ASM on the disease may be related to its ability to enhance defence responses in the fruit. The application of ASM in inducing resistance in fruit possesses promising in control of postharvest diseases alternative to fungicides. [source] Impact of sorghum processing on phytate, phenolic compounds and in vitro solubility of iron and zinc in thick porridgesJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 5 2007AP Polycarpe Kayodé Abstract This study focussed on the impact of process variables on levels of phytate and phenolic compounds, and in vitro solubility of iron (Fe) and zinc (Zn) in sorghum porridges, a major staple in semi-arid tropics. The aim was to identify practices that enhance the mineral availability in this type of staple food. We studied the example of the West African porridge ,dibou' for which the processing methods involve grain cleaning, milling, sieving and cooking. Regional variations occur in the process, particularly in the cleaning which may be done wet or dry; sieving may be omitted in certain locations. Cleaning reduced the phytate content of the grain by 24,39%, while milling, sieving and cooking had no significant effect on phytate. Phenolic compounds measured as levels of reactive hydroxyl groups, remained constant after cleaning, milling and sieving, but significantly decreased by 38,65% after cooking. The Fe solubility tended to increase after cleaning but was drastically reduced due to cooking, and so was the soluble Zn. Levels of total phenolic compounds highly correlated with the Fe and Zn solubility (r2 = 0.73 and 0.82, respectively). Phenolic reaction products formed during the cooking process are presumably related with the extensive browning phenomenon observed in the dibou porridge, and with the reduction observed in Fe and Zn solubility. Copyright © 2007 Society of Chemical Industry [source] Free-radical scavenging activity of wormwood (Artemisia absinthium L) extractsJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 2 2005Jasna M Canadanovic-Brunet Abstract In an effort to discover new antioxidant natural compounds, wormwood (Artemisia absinthium L) an aromatic-bitter herb, was screened. The sequential extraction was realized with five solvents of different polarities (70% methanol, petroleum ether, chloroform, ethyl acetate, n -butanol). The antioxidative activity was tested by measuring their ability to scavenge stable 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical and reactive hydroxyl radical during the Fenton reaction trapped by 5,5-dimethyl-1-pyrroline- N -oxide (DMPO), using electron spin resonance (ESR) spectroscopy. Results demonstrated that the antiradical and antioxidative activity depend on the type and concentration of applied extracts and increased in the order ethyl acetate > methanol > n -butanol > chloroform > petroleum ether > remaining water extracts. The investigation showed that the antiradical activity increased with increasing concentration of all extracts. The high contents of total phenolic compounds (25.6 mg g,1) and total flavonoids (13.06 mg g,1) indicated that these compounds contribute to the antiradical and antioxidative activity. In a model system, the formation of o -semiquinone radicals from quercetin and chlorogenic acid was obtained to prove the mechanism (hydrogen donating and/or one-electron reduction) of free-radical scavenging activity. Copyright © 2004 Society of Chemical Industry [source] Total antioxidant capacity and content of flavonoids and other phenolic compounds in canihua (Chenopodium pallidicaule): An Andean pseudocerealMOLECULAR NUTRITION & FOOD RESEARCH (FORMERLY NAHRUNG/FOOD), Issue 6 2008J. Mauricio Peñarrieta Abstract Total antioxidant capacity (TAC), total phenolic compounds (TPH), total flavonoids (TF) and individual phenolic compounds were determined in canihua collected at approx. 3850 m altitude. The TAC values varied among samples from 2.7 to 44.7 by the ferric reducing antioxidant power (FRAP) method and from 1.8 to 41 by the 2,2,-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) method expressed as ,mol of Trolox equivalents/g dw. The content of TPH was 12.4,71.2 ,mol gallic acid equivalents/g dw and that of the TF ranged between 2.2 and 11.4 ,mol of catechin equivalents/g dw. The data obtained by the four methods showed several significant correlations. Prior to analysis by HPLC, the samples were subjected to acid hydrolysis and in the water-soluble extracts this led to an up to 20-fold increase in the TAC values in comparison with the values of the nonhydrolysed samples. HPLC analysis showed the presence of eight major compounds identified as catechin gallate, catechin, vanillic acid, kaempferol, ferulic acid, quercetin, resorcinol and 4-methylresorcinol. Their estimated contribution to the TAC value (FRAP method) indicated that resorcinols contributed most of the antioxidant capacity of the water-soluble extract. The results show that canihua is a potential source of natural antioxidant compounds and other bioactive compounds which can be important for human health. [source] Chemical composition and antibacterial activities of lupin seeds extractsMOLECULAR NUTRITION & FOOD RESEARCH (FORMERLY NAHRUNG/FOOD), Issue 5 2003Eleonora Lampart-Szczapa Abstract Determination of influence of lupin natural phenolic compounds on antibacterial properties of its seeds was carried out. Raw material were seeds of Lupinus albus, L. luteus, and L. angustifolius. The methods included the determination of the content of proteins, total phenolic compounds, free phenolic acids, and tannins as well as antibacterial properties with ethanol extracts. The content of total phenolic compounds was smaller in testas than in cotyledons and the highest levels are observed in bitter cultivars of Lupinus albus cv. Bac andL. angustifolius cv. Mirela. Lupin tannins mainly occurred in cotyledons of the white lupin, predominantly in the bitter cultivar Bac. Free phenolic acids were mainly found in testas. Only extracts from the testas displayed antibacterial properties, which excludes the possibility of alkaloid influence on the results. The results suggest that inhibition of test bacteria growth depended mainly upon the content of the total phenolic compounds. [source] | |||||||||||||