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71.
Casado FJ Sánchez AH Rejano L Montaño A 《Journal of agricultural and food chemistry》2007,55(9):3503-3507
The occurrence of d-amino acids in commercial ripe olives, a well-known sterilized alkali-treated product, was investigated by high-performance liquid chromatography (HPLC) with precolumn automatic derivatization. Absolute amounts of D-amino acids were in total 18.6-38.2 mg/100 g edible portion. The major D-amino acids were D-aspartic acid, D-glutamic acid, D-serine, and D-leucine. Furthermore, to evaluate the effects of sterilization time and olive pH on amino acid racemization, a simulated processing of green ripe olives was carried out. Serine (both free and bound form) was the most-racemized amino acid after heat treatment. Sterilization (15-35 min at 121 degrees C) increased the racemization values of both free and protein-bound amino acids, although in case of protein-bound phenylalanine the increase was not statistically significant. With an increase of pH from 8 to 10 units, the racemization values of all amino acids increased significantly, except for free forms of aspartic and glutamic acids. In general, the effects of the sterilization time and olive pH on total concentration (L + D enantiomers) of each amino acid were also significant. 相似文献
72.
Pérez-López AJ López-Nicolas JM Núñez-Delicado E Del Amor FM Carbonell-Barrachina AA 《Journal of agricultural and food chemistry》2007,55(20):8158-8164
Consumers demand organic products because they believe they are more flavorful and respectful to the environment and human health. The effects of conventional, integrated, and organic farming, grown in a controlled greenhouse, on color, minerals, and carotenoids of sweet pepper fruits ( Capsicum annuum), cv. Almuden, were studied. Experimental results proved that organic farming provided peppers with the highest (a) intensities of red and yellow colors, (b) contents of minerals, and (c) total carotenoids. Integrated fruits presented intermediate values of the quality parameters under study, and conventional fruits were those with the lowest values of minerals, carotenoids, and color intensity. As an example, the concentrations of total carotenoids were 3231, 2493, and 1829 mg kg (-1) for organic, integrated, and conventional sweet peppers, respectively. Finally, organic red peppers could be considered as those having the highest antioxidant activity of all studied peppers (agricultural farming and development stage). 相似文献
73.
Jaime L Mendiola JA Ibáñez E Martin-Alvarez PJ Cifuentes A Reglero G Señoráns FJ 《Journal of agricultural and food chemistry》2007,55(26):10585-10590
In the present work sub- and supercritical extraction conditions using carbon dioxide were studied in order to obtain extracts with different compositions from the green microalgae Dunaliella salina. Different compositions of beta-carotene isomers were identified in the extracts by using HPLC-DAD. Also, antioxidant activity of the extracts was measured using a TEAC assay. An experimental design was applied considering two factors, extraction pressure and temperature, in a wide range of values, trying to maximize the extraction yield. Higher yields were obtained at high pressures and low temperatures, that is, at higher CO2 densities. Attempts were made to correlate the antioxidant activity of the extracts with their chemical composition by means of principal component analysis. A certain relationship was found between their antioxidant activity and the isomeric composition of beta-carotenes. As a result, an original equation is proposed to predict the antioxidant activity of extracts from D. salina in terms of the ratio 9-cis-beta-carotene/all-trans-beta-carotene, the concentration of alpha-carotene, and, especially, the concentration of 9-cis-beta-carotene. 相似文献
74.
Traditionally antioxidant activity of melanoidins has only been evaluated in food for implication in shelf life but gastrointestinal digestion is necessary to study their potential bioactivity. In addition, the biological fate of melanoidins has been stressed during the past decade since they did not behave as inert substances. In the present paper a soluble coffee melanoidin isolated from brewed coffee after ultrafiltration with a 10 kDa cutoff membrane was treated ionically and enzymatically collecting the respective high and low molecular weight fractions. Antioxidant activity of these fractions was evaluated with five well-described assays (DPPH, ABTS, ORAC, HOSC, and FRAP) that were previously setup in a plate reader based automatized analysis. Low molecular weight compounds released from melanoidin after gastrointestinal digestion exerted the highest antioxidant activity, even higher than compounds bound ionically to melanoidins. Gastrointestinal digestion is able to modify coffee melanoidins to some extent, as hypothesized from their absolute antioxidant activities. Two options are plausible: by modifying/releasing the ionically bound compounds and/or by genesis of new more active structures from the melanoidin skeleton after enzymatic treatment. 相似文献
75.
Sotelo A López-García S Basurto-Peña F 《Plant foods for human nutrition (Dordrecht, Netherlands)》2007,62(3):133-138
Nutrient and antinutritional/toxic factors present in some edible flowers consumed in Mexico were determined. The edible flowers
were: Agave salmiana, Aloe vera, Arbutus xalapensis, Cucurbita pepo (cultivated), Erythrina americana, Erythrina caribaea, Euphorbia radians benth and Yucca filifera. The nutrient content in the flowers studied is similar to that of the edible leaves and flowers studied mainly in Africa.
The moisture content of the flowers varied from 860 to 932 g kg−1. Crude protein (CP) was between 113 to 275 g kg−1 DM, crude fiber, 104 to 177 g kg−1 DM and the nitrogen free extract, between 425 to 667 g kg−1 DM. The highest chemical score (CS) was found in E. americana and A. salmiana; in five samples the limiting amino acid was lysine, and in three of them it was tryptophan. Trypsin inhibitors and hemaglutinnins
had a very low concentration. Alkaloids were present in both the Erythrina species and the saponins in A. salmiana and Y. filifera. Cyanogenic glucosides were not found in the studied flowers. The traditional process of preparing these specific flowers
before consumption is by cooking them and discarding the broth; in this way the toxic substances are diminished or eliminated.
These edible flowers from wild plants consumed in local areas of the country play an important role in the diet of the people
at least during the short time of the season where they are blooming. 相似文献
76.
77.
Daz-Siefer Pablo Olmos-Moya Natalia Fontrbel Francisco E. Lavandero Blas Pozo Roco A. Celis-Diez Juan L. 《Journal of pest science》2022,95(2):567-576
Journal of Pest Science - Birds provide important ecosystem services in many ecosystems, including important pest control effects on productive systems. The typically low bird diversity observed in... 相似文献
78.
Primo Anacláudia Alves Araújo Maria Diana Melo Silva Karla da Fonseca Silva Ludmyla Araújo Pereira Graziella de Andrade Carvalho Fernandes Francisco Éden Paiva Pompeu Roberto Cláudio Fernandes Franco Natale William de Souza Henrique Antunes 《Agroforestry Systems》2021,95(8):1459-1464
Agroforestry Systems - The use of native trees in agroecosystems is a promising way to increase litter deposition and nutrient cycling and foster the recovery of degraded areas, especially in... 相似文献
79.
Patrícia Castro Monteiro Maria Inês Braga de Oliveira Franmir Rodrigues Brando Caio Francisco Santana Farias Cludia Majolo Francisco Clio Maia Chaves Humberto Ribeiro Bizzo Fernanda Loureiro de Almeida OSullivan Maurício Latera Martins Edsandra Campos Chagas 《Aquaculture Research》2022,53(1):265-275
This study evaluated the effect of short-term baths with the essential oils (EOs) of Lippia sidoides, Ocimum gratissimum and Zingiber officinale on the survival, haematological, biochemical and histopathological parameters of native fish tambaqui (Colossoma macropomum), challenged with Aeromonas hydrophila. After challenge, the fish infected with A. hydrophila received therapeutic baths of 60 min, for five consecutive days. Treatments were as follows: challenged and not treated; challenged and treated with 10 mg L?1 of gentamicin; challenged and treated with EO of L. sidoides (2.5 and 5.0 mg L?1); challenged and treated with EO of O. gratissimum (5.0 and 10.0 mg L?1); challenged and treated with Z. officinale EO (5.0 and 10.0 mg L?1). The highest survival rates were 89.5% (fish treated with 5.0 mg L?1 of O. gratissimum EO) and 75.0% (fish treated with 5.0 mg L?1 of L. sidoides EO). Reductions in the haematocrit percentage, haemoglobin and erythrocyte number were observed in fish treated with L. sidoides and Z. officinale EOs compared with control fish. Mild to moderate damage to the liver tissue of fish after challenge and EO treatments were observed. It is suggested that baths containing O. gratissimum and L. sidoides EOs consist in a viable treatment to increase survival rates of C. macropomum infected with A. hydrophila. 相似文献
80.
Sandra Villagmez-Estrada Jos F Prez Sandra van Kuijk Diego Melo-Durn Asal Forouzandeh Francesc Gonzalez-Sol Matilde DAngelo Francisco J Prez-Cano David Sol-Oriol 《Journal of animal science》2021,99(7)
The aim of the present study was to evaluate the effect of trace mineral nutrition on sow performance, mineral content, and intestinal gene expression of neonate piglets when inorganic mineral sources (ITM) were partially replaced by their organic mineral (OTM) counterparts. At 35 d postmating, under commercial conditions, a total of 240 hyperprolific multiparous sows were allocated into three experimental diets: 1) ITM: with Zn, Cu, and Mn at 80, 15, and 60 mg/kg, respectively; 2) partial replacement trace mineral source (Replace): with a 30 % replacement of ITM by OTM, resulting in ITM + OTM supplementation of Zn (56 + 24 mg/kg), Cu (10.5 + 4.5 mg/kg), and Mn (42 + 18 mg/kg); and 3) Reduce and replace mineral source (R&R): reducing a 50% of the ITM source of Zn (40 + 24 mg/kg), Cu (7.5 + 4.5 mg/kg), and Mn (30 + 18 mg/kg). At farrowing, 40 piglets were selected, based on birth weight (light: <800 g, and average: >1,200 g), for sampling. Since the present study aimed to reflect results under commercial conditions, it was difficult to get an equal parity number between the experimental diets. Overall, no differences between experimental diets on sow reproductive performance were observed. Light piglets had a lower mineral content (P < 0.05) and a downregulation of several genes (P < 0.10) involved in physiological functions compared with their average littermates. Neonate piglets born from Replace sows had an upregulation of genes involved in functions like immunity and gut barrier, compared with those born from ITM sows (P < 0.10), particularly in light piglets. In conclusion, the partial replacement of ITM by their OTM counterparts represents an alternative to the totally inorganic supplementation with improvements on neonate piglet gene expression, particularly in the smallest piglets of the litter. The lower trace mineral storage together with the greater downregulation of gut health genes exposed the immaturity and vulnerability of small piglets. 相似文献