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831.
Aqueous and ethanolic extracts obtained from nine Chilean marine macro-algae collected at different seasons were examined in vitro and in vivo for properties that reduce the growth of plant pathogens or decrease the injury severity of plant foliar tissues following pathogen infection. Particular crude aqueous or organic extracts showed effects on the growth of pathogenic bacteria whereas others displayed important effects against pathogenic fungi or viruses, either by inhibiting fungal mycelia growth or by reducing the disease symptoms in leaves caused by pathogen challenge. Organic extracts obtained from the brown-alga Lessonia trabeculata inhibited bacterial growth and reduced both the number and size of the necrotic lesion in tomato leaves following infection with Botrytis cinerea. Aqueous and ethanolic extracts from the red-alga Gracillaria chilensis prevent the growth of Phytophthora cinnamomi, showing a response which depends on doses and collecting-time. Similarly, aqueous and ethanolic extracts from the brown-alga Durvillaea antarctica were able to diminish the damage caused by tobacco mosaic virus (TMV) in tobacco leaves, and the aqueous procedure is, in addition, more effective and seasonally independent. These results suggest that macro-algae contain compounds with different chemical properties which could be considered for controlling specific plant pathogens. 相似文献
832.
Carvajal-Zarrabal O Waliszewski SM Barradas-Dermitz DM Orta-Flores Z Hayward-Jones PM Nolasco-Hipólito C Angulo-Guerrero O Sánchez-Ricaño R Infanzón RM Trujillo PR 《Plant foods for human nutrition (Dordrecht, Netherlands)》2005,60(4):153-159
The scientific basis for the statement that plants and their active constituents play an important role in the prevention
of chronic and degenerative diseases is continously advancing. The object of the present study was to evaluate the effect
of Hibiscus sabdariffa L. dried calyx ethanolic extract on the serum lipid profile of Sprague-Dawley rats. The rats were fed during 4 weeks with
either a basal diet, containing high cholesterol (1%), cholic acid (0.25%), lard oil (10%), or a supplemental diet with H. sabdariffa extract at 5%, 10%, and 15% levels (SD5, SD10, SD15). Weight gain and faeces dry weight were both very significantly less (p ≤ 0.01) in SD10 and SD15 groups as compared to the control group, as was food efficiency in SD15. In the case of SD10, food efficiency was only significantly lower (p ≤ 0.05). Faeces dry weight in SD5 however, was the only one found to be significantly higher (p ≤ 0.05). Triacylglycerols and LDL levels were both significantly less (p ≤ 0.05) in all groups (SD5, SD10, and SD15) as compared to the control. For total lipids, SD10 and SD15 showed significantly lower levels (p ≤ 0.05), whereas very significant differences (p ≤ 0.01) were observed in the case of SD5. All groups had lower cholesterol levels compared to controls; however, only the SD5 group was statistically significant (p ≤ 0.05). No significant results were found in any group in the cases of either phospholipid or HDL levels. A hypothesis of
hibiscus acid racemization, (+)-HCA to (−)-HCA, mediated by intestinal flora enzymes possibly explains the significant triacylglycerol
decrease in all experimental groups. VLDL, the precursor of LDL, is composed predominantly of triacylglycerols, suggesting
that the significant decrease in LDL is related to observed triacylglycerol synthesis inhibition. Five percent H. sabdariffa extract addition showed the best results in the reduction of serum lipids under study conditions. 相似文献
833.
González-Espinosa de los Monteros LA Ramón-Gallegos E Torres-Torres N Mora-Escobedo R 《Plant foods for human nutrition (Dordrecht, Netherlands)》2011,66(4):355-362
Germination of soybeans increases the bioavailability of some nutrients. An evaluation was done to determine if germination
increased the anti-adipogenic and lipolytic effects of soybean. Soybeans were germinated for 0 to 6 days and protein concentrates
extracted from beans germinated at each period. Soy protein concentrates can retain notable amounts of phytochemicals with
anti-adipogenic activity. For this reason, it was evaluated the effect of protein hydrolysates with and without phytochemicals
in the adipocyte-like cells after 3T3-L1 (murine fibroblasts) cell line differentiation. Cell viability decreased with exposure
to the germinated soybean protein hydrolysates during the differentiation stage, but not during the fibroblast or mature adipocyte
stages. Adipogenesis and triglycerides accumulation were strongly inhibited by the hydrolysate from soybeans germinated for
2 days (with ethanol-soluble phytochemicals), when compared to ungerminated soybean. Adipolysis increased with exposure to
hydrolysates from beans germinated for 2 days (with phytochemicals) and 5 days (without phytochemicals). Germinated soy protein
hydrolysates had an effect on inhibition of lipid storage in adypocites and increasing lipolysis, which was improved by changes
of the protein and increased phytochemical content due to germination. 相似文献
834.
Gonzalez-Saiz JM Pizarro C Esteban-Díez I Ramírez O Gonzalez-Navarro CJ Saiz-Abajo MJ Itoiz R 《Journal of agricultural and food chemistry》2007,55(8):2930-2936
The valorization of vegetable byproducts is one of the main objectives of industry today. The project on which this study is based examined the potential usefulness of worthless onions (Allium cepa L. sp.) and overproduction to obtain several functional products with different applications in the food industry. Near-infrared (NIR) spectroscopy, combined with multivariate calibration, has been used to monitor the alcoholic fermentation of onion juice. Good results were obtained, revealing the suitability of NIR spectroscopy for controlling and optimizing this process in real time. 相似文献
835.
Volatile profiles of two Iberian dry-cured products, dry-cured loin and ham, from three different Iberian x Duroc genotypes, was assessed. Three groups of 10 pigs, each (5 males and 5 females) from different genotypes, were studied: GEN1 = male Iberian x female Duroc1; GEN2 = male Duroc1 x female Iberian; and GEN3 = male Duroc2 x female Iberian. The genotype Duroc1 (DU1) corresponded to pigs selected for the production of dry-cured meat products (hams, loins, and shoulders), with a high level of fattening, while the genotype Duroc2 (DU2) corresponded to animals selected for meat production. Genotype slightly affected the volatile profiles of both dry-cured meat products, although dry-cured loin from GEN3 showed higher hexanal content. Dry-cured loin showed a volatile profile very different to that found in dry-cured ham. Volatile compounds of dry-cured meat products were mainly originated by lipid and protein degradation. Most of the volatile detected in both meat products came from lipid oxidation such as acids, aldehydes, ketones, alcohols, and hydrocarbons. In addition, a high proportion of volatile compounds from the Maillard reaction was found. Branched aldehydes and some sulfur and nitrogen compounds have their origin in the amino acids degradation by the Strecker reaction, while branched alcohols and acids come from the lipid oxidation of branched aldehydes. Dry-cured ham showed a higher number and a higher level of compounds with origin in protein and lipid degradation than dry-cured loin, which agrees with the longer ripening of the hams (24 months) with respect to the loins (4 months). In dry-cured loins, apart from these compounds, seasoning mixture provides high amount of volatiles, such as terpenes (from paprika and oregano) and sulfur compounds (from garlic), which have great importance in the overall aroma of this product. 相似文献
836.
Fabiola G. Valenzuela Que Gilberto Villanueva-López Alejandro Alcudia-Aguilar Ojilve Ramón Medrano-Pérez Luisa Cámara-Cabrales Pablo Martínez-Zurimendi Fernando Casanova-Lugo Deb Raj Aryal 《Soil Use and Management》2022,38(2):1237-1249
Silvopastoral systems have great potential for storing carbon because of carbon assimilation in tree woody biomass, carbon input through litterfall and below-ground carbon turnover. In this study, we quantified and compared the carbon stocks at livestock ranches in Tabasco, Mexico, containing either scattered trees in grazing pastures (STP) or grass monocultures. Sampling plots were randomly established at each ranch where the above- and below-ground carbon stocks, carbon input from litterfall, grass production and arboreal biomass growth were measured. We found that silvopastoral systems stored an average of 257.45 Mg ha−1 of soil organic carbon (SOC) compared to 119.17 Mg SOC ha−1 at grass monoculture ranches (to 30 cm depth); silvopastoral systems also stored 44.64 Mg C ha−1 in wood biomass; and, grass monocultures had greater cumulative grass biomass production. Overall, it is concluded that livestock ranches in Tabasco, Mexico, with scattered trees in grazing pastures stored 58.8% more carbon than those grass monocultures, with carbon stocks of 327.01 Mg C ha−1and 134.47 Mg C ha−1, respectively. The results are useful for land management decision making for sustainable livestock systems framed in the Sustainable Development Goals (SDGs). 相似文献
837.
The sodium hydroxide (NaOH) test for determining wheat color class depends on the observation that on soaking in NaOH, red wheat turns a darker red and white wheat turns straw yellow. To understand the mechanism of this test, Raman spectra of wheat bran, wheat starch, ferulic acid, and whole kernels of wheat, before and after NaOH soak, were studied. The major observable components in the whole kernel were that of starch, protein, and ferulic acid, perhaps esterified to arabinoxylan and sterols. When kernels are soaked in NaOH, spectral bands due to ferulic acid shift to lower energy and show a slightly reduced intensity that is consistent with deprotonation of the phenolic group and extraction of a portion of the ferulic acid into solution. Other phenolic acids, alkyl resorcinols, and flavonoids observed in the NaOH extracts of wheat by HPLC were not observed in the Raman spectra. Wheat bran accounts for most of the ferulic acid in the whole kernel, as indicated by the increased intensity of the doublet at 1,631 and 1,600 cm‐1 in the bran. The intense starch band at 480 cm‐1 in whole kernel wheat was nearly absent in the wheat bran. 相似文献
838.
Arely Ramírez-García Omar Domínguez-Domínguez Eugenia López-López Rodrigo Moncayo-Estrada José De La Cruz-Agüero 《Ecology of Freshwater Fish》2023,32(1):53-63
In spring lakes, which have homogeneous environmental characteristics, it is expected that there will be no significant changes in the composition and structure of communities over time, and fluctuations will generally be related to the ecological attributes of the species. We studied the fish community in a small subtropical spring lake, Lake Zacapu, for two different decades to analyse its structural characteristics. Sampling was performed every 3 months at four sites from January to October 1995 and from May 2019 to May 2020. We determined the temporal variation (seasonal and decadal) in the fish community structure with respect to composition, abundance, diversity and dominance. We evaluated the association between species and water quality. Our results showed spatial homogeneity in most physicochemical variables that remained in the same range across decades, although some nutrients (NO3) recently increased. All species identified in the early samples were present in the recent surveys (eleven native and two nonnative species), indicating that the fish community composition had significant qualitative stability. However, the dominant littoral cyprinid in 1995 was replaced by the more limnetic atherinopsid in 2019–2020, and the diversity and abundance of sensitive fish decreased in recent samplings. Consequently, the current status of critically endangered species is supported for some restricted and microendemic fish. The changes in the community structure attributes, which show a tendency for reduction in native species, emphasise the need to implement efforts to conserve freshwater fish diversity in small spring lakes. 相似文献