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991.
Irene Romero María T. Sanchez-Ballesta María I. Escribano Carmen Merodio 《Postharvest Biology and Technology》2008,49(1):1-9
In this study, we have analyzed the profiles of individual anthocyanins in the skin of Cardinal table grapes and their contribution to the total antioxidant capacity (TAC) in response to low temperature (0 °C) and high CO2 levels (20% for 3 days). An analysis of the representative colour parameters of this red-violet variety was also determined. The anthocyanin composition was determined using high-performance liquid chromatography coupled to diode array detector and mass spectrometry (HPLC–DAD–MS). The contribution of individual anthocyanins to the TAC value of table grapes was calculated on the basis of their concentration and antioxidant capacity measured as the TEAC value (slope of the anthocyanin/slope of Trolox). Chromatographic analysis identified six anthocyanins, including pelargonidin 3-glucoside (Pg-3-G), in the skin of Cardinal table grapes. Short-term storage at 0 °C in air had an increasing effect on the concentration of each of the identified anthocyanins. After 3 days at 0 °C, untreated grapes had the highest anthocyanin content (27.55 mg/100 g FW) and displayed the largest TAC value (52.45 mM TE/100 g FW). Peonidin 3-glucoside (Pn-3-G) was the predominant anthocyanin, and it was mainly responsible for the rise in the calculated TAC value in untreated grapes. Pn-3-G had a low average TEAC value (1.73 mM), but its contribution could be explained by the sharp increase in the content of this anthocyanin the first days of storage at 0 °C. In contrast, the Pn-3-G content in grapes at the end of the 3-day CO2 treatment did not change, and both the total anthocyanin content and the calculated TAC value remained significantly constant in comparison to the levels in pre-stored grapes. In addition CO2 treatment had a positive effect on the amount of Pg-3-G concomitant with a pronounced decline in delphinidin 3-glucoside (Dp-3-G) and smaller decreases in petunidin 3-glucoside (Pt-3-G) and malvidin 3-glucoside (Mv-3-G). These effects of high CO2 levels on the profile of individual anthocyanins were progressively lost when grapes were transferred to air. Indeed, after prolonged low-temperature storage when the colour of the berries become dark violet, similar calculated TAC values were quantified in untreated grapes and in those exposed to 20% CO2. These data provide new insights about the effect of low temperature and high CO2 levels on the concentration of the individual anthocyanins identified in cardinal table grapes. 相似文献
992.
Campos Isidro González-Gómez Laura Villodre Julio Calera Maria Campoy Jaime Jiménez Nuria Plaza Carmen Sánchez-Prieto Sergio Calera Alfonso 《Precision Agriculture》2019,20(2):214-236
Precision Agriculture - This paper explored the ability of remote sensing (RS) and meteorological data to map the variability of yield/biomass in cultivated wheat (Triticum aestivum). The... 相似文献
993.
Nazareth Torres Daniel Plano M. Carmen Antolín Carmen Sanmartín Maite Domínguez-Fernández María-Paz De Peña 《Archives of Agronomy and Soil Science》2019,65(10):1341-1353
Grapevine leaves are widely discarded in open fields despite their known antioxidant properties. We tested the cytotoxicity of leaf extracts from three clones (CL-260, CL-1048, CL-8) of Vitis vinifera L. cv. Tempranillo against four human cancer cell lines: colon, HT-29; breast, MCF-7; lung HTB-54; and lymphoblastic leukemia, CCRF-CEM. Grapevines were cultivated at either ambient (24/14 °C) or elevated (28/18 °C) day/night temperatures, and inoculated (+M) or not (-M) with arbuscular mycorrhizal fungi (AMF). Cytotoxicity was analysed by MTT assays. Elevated air temperatures enhanced the cytotoxicity of leaf extracts from CL-260 against HT-29, CCRF-CEM and HTB-54 and that from CL-8 against MCF-7. Mycorrhization improved the cytotoxicity of leaf extracts from CL-1048 against HT-29, CCRF-CEM, HTB-54 and MCF-7. The cytotoxic activities of CL-260 against HTB-54 and CL-1048 against HT-29 were correlated, respectively, with total phenols and total antioxidant capacity. We conclude that the predicted increase in air temperature for the future climate and the mycorrhizal association of grapevines may enhance the cytotoxicity of leaves, which strengthens the potential application of these agricultural residuals for biomedicine. However, the clonal diversity in the response to AMF and air temperature highlights the importance of choosing the most adequate clone for a concrete environmental scenario. 相似文献
994.
Weber John C. Sotelo Montes Carmen Soumana Idrissa Diallo Boukary Ousmane Abasse Tougiani Larwanou Mahamane Bationo André Babou 《New Forests》2019,50(4):643-661
New Forests - Some tree improvement programs in Africa use nursery tests to investigate genetic and geographic variation in growth, but do they lead to the same conclusions as field tests? We... 相似文献
995.
Diez-Ercilla Marta Falagán Carmen Yusta Iñaki Sánchez-España Javier 《Journal of Soils and Sediments》2019,19(3):1527-1542
Journal of Soils and Sediments - Biogeochemical processes occurring in lake sediments are crucial for element cycling. In acidic pit lakes, they play a major role in acidity neutralization and... 相似文献
996.
The current situation of worldwide concern over the emission of greenhouse gases and its effect on the climate demands an evaluation, from the perspective of energy efficiency and more specifically of non-renewable energy sources, of tendencies for change in the management of agricultural systems which have arisen in recent years. This article uses energy balances to evaluate the contribution of organic olive growing to the increase in the energy efficiency of Mediterranean agriculture, distinguished according to type of watering regime and intensiveness of cultivation. The results show, on one side, the lower energy efficiency of irrigated land as opposed to dryland (i.e. non-irrigated) regardless of their style of management and, on the other, the greater non-renewable energy efficiency of organic olive growing in comparison with the conventional production. Nevertheless, organic management could still improve its energy efficiency if it further adjusts and internalizes the flows of nutrients needed in order to achieve greater sustainability. 相似文献
997.
Geographic variation in tree growth and wood density of <Emphasis Type="Italic">Guazuma crinita</Emphasis> Mart. in the Peruvian Amazon 总被引:1,自引:0,他引:1
Guazuma crinita Mart. is a fast-growing timber tree in the Peruvian Amazon. A trial of 11 Peruvian provenances was established in three planting
zones. Tree growth at 6, 12, 18 and 30 months and wood density at 32 months were analyzed across and within zones. Zones accounted
for more variation than provenances. Density varied significantly due to provenances in the analysis across zones, whereas
growth exhibited strong provenance by zone interactions. The local provenance grew well and produced relatively dense wood
in all zones. The relative magnitude of variation due to provenances depended on the planting zone. Density was greater in
the lower than in the upper stem. Density increased with longitude from the more humid to the drier part of the sample region.
In general, correlations indicated that larger trees had lower density and a larger difference in density between the lower
and upper stem, but the strength of these relationships depended on the provenance and zone. Results suggest that fast-growing
provenances can be selected at an early age without significantly reducing wood density. The local provenance is recommended
for reforestation pending future research demonstrating the superiority of foreign provenances. Some practical implications
for tree-improvement programs are discussed. 相似文献
998.
This work concerns the pharmacological activity of inuviscolide, a sesquiterpenoid from Inula viscosa. It exerts inhibitory effects on elastase, cyclooxygenase 1 and secretory phospholipase A(2). Furthermore, it reduces the skin leukocyte infiltration in a murine model of dermatitis induced by repeated application of 12-O-tetradecanoylphorbol 13-acetate. 相似文献
999.
R. Mora-Escobedo Maria del Carmen Robles-Ramírez Eva Ramón-Gallegos Rafael Reza-Alemán 《Plant foods for human nutrition (Dordrecht, Netherlands)》2009,64(4):271-278
Consumption of soybeans can reduce the risk of different types of cancer. Little is known about the effect of germination
on the anticancer properties of soya. This study was done to determine if germination improves the anticancer properties of
soybean protein through generation of amino acids or bioactive peptides. Soybean was germinated for 0, 2, 3, 4, 5, and 6 days
and proteins were isolated from the seeds. Isolates with and without ethanol-soluble phytochemicals were hydrolyzed with digestive
enzymes and their effect on growth in HeLa and C-33 (epidermoid cervical carcinoma) and HaCaT (non-cancerous human keratinocytes)
cells were evaluated with the Alamar Blue method. Germination induced degradation of the α and α’ fractions of β-conglycinin
and acid fraction of glycinin, generating low molecular weight peptides. Degrees of hydrolysis ranged from 73–77%. Hydrolysates
inhibited the growth of HeLa cells and C-33 at concentrations exceeding 1.25 mg/ml. Major inhibition was observed with the
hydrolysate germinated for 2 days and containing ethanolsoluble phytochemicals (IC50 2.15 and 2.27 mg/ml for HeLa and C-33, respectively). Interestingly, hydrolysate cytoxicity for normal cells was minimal
in comparison to cancer cells. 相似文献
1000.
Olga Alvarez Colom Isabel Barrachina Ildefonso Ayala Mingol M. Carmen Gonzalez Mas Pilar Moya Sanz Adriana Neske Alicia Bardon 《Journal of pest science》2008,81(2):85-89
From an Argentine collection of Annona cherimolia and a Bolivian collection of Annona montana (Annonaceae), the acetogenins, squamocin, molvizarin, itrabin, almuñequin, cherimolin-1, annonacin, annonacin-A, densicomacin-1, cis-annonacin-10-one and murihexocin-A, were obtained to study their toxicity against the cotton pest Oncopeltus fasciatus (Hemiptera: Lygaeidae). Topical ventral application of O. fasciatus nymphs with solutions of the mentioned acetogenins produced acute and delayed mortality. 相似文献