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排序方式: 共有349条查询结果,搜索用时 203 毫秒
71.
Enrique Ritter Leire Barandalla Raquel López José Ignacio Ruiz de Galarreta 《Potato Research》2008,51(3-4):301-311
Native potato species (NPS) are cultivated potatoes which do not belong to S. tuberosum ssp. tuberosum. They are maintained by the farmers of the Andes for subsistence under harsh environmental conditions where other potatoes cannot compete. Within the huge phenotypic variability between and within these species certain accessions possess resistances to different pests and diseases, remarkable culinary and processing quality and favourable nutritional properties. We present first evaluation results of a set of NPS for these characters and discuss prospects for exploiting this valuable germplasm for breeding and for developing novel products for niche markets. 相似文献
72.
The use of anaesthetic agents has been increasing to address the welfare needs of different fish species in scientific and aquaculture practices. MS-222 is the most used synthetic anaesthetic but some limitations and side effects have been reported. Natural substances have been used as potential substitutes with clove oil playing an important role due to its eugenol content. Yet, other monoterpenes have shown anaesthetic properties in different fish species. As such, a quantitative assessment has been conducted to explicitly relate and summarise the use of monoterpenes with described anaesthetic properties in fish. A combined PubMed, Web of Science, Scopus, PubMed Central and Europe PMC electronic database search was performed, from January 2002 to August 2022, following the PRISMA guidelines. Out of 1555 articles retrieved from the literature search, 30 English reports met the criteria for inclusion in the meta-analysis through a generic inverse-variance method (random-effects model) and according to the fish age. The findings show a total of 10 different monoterpenes with high homogeneity and effectiveness in inducing anaesthesia and recovery according to the fish anaesthetic criteria. Further subgroup analysis showed these effects were independent of fish age. Meta-regression of the included studies revealed an inverse linear association between anaesthesia induction and recovery time and water bath temperature while no further correlation was found with other confounding factors (body weight, water pH and dissolved oxygen levels). Although further studies will be required, this meta-analysis provides robust evidence that different monoterpenes serve as an attractive and effective alternative for fish anaesthesia although water bath temperature also played an important role in anaesthesia outcome. 相似文献
73.
Esteban R Jiménez ET Jiménez MS Morales D Hormaetxe K Becerril JM García-Plazaola JI 《Tree physiology》2007,27(10):1407-1414
Two xanthophyll cycles have been described in higher plants: the violaxanthin xanthophyll (V or VAZ) cycle, which is present in all species, and the taxonomically restricted lutein epoxide xanthophyll (Lx) cycle, which involves the light-induced de-epoxidation of Lx to lutein (L) and its epoxidation back to Lx in low light. Laboratory experiments indicate that the first reaction occurs quickly, but the second reaction is much slower. We investigated the Lx cycle under field conditions in several tree species of the Lauraceae family to determine its relationship with the ubiquitous V cycle. The field study was conducted in two natural laurel forests: one in the Canary Islands, where Laurus azorica (Seub.) Franco, Ocotea foetens (Aiton.) Benth, Apollonias barbujana (Cav.) Bornm. and Persea indica (L.) Spreng were studied; and one in the Basque Atlantic coast where Laurus nobilis L. was studied. The results were complemented by a taxonomic study. The presence of Lx was widespread among Lauraceae species, but its concentration varied even among closely related species. The V pool size correlated positively with growth irradiance, whereas the relationship between Lx pool size and growth irradiance varied with species. A functional Lx cycle was confirmed under field conditions only in O. foetens and L. nobilis. Furthermore, in O. foetens, a correlation between Lx de-epoxidation and photoinhibition suggested a protective role for this cycle. We conclude that, unlike the V cycle, which is normally correlated with irradiance, the operation and light dependence of the Lx cycle is species-dependent. 相似文献
74.
Raquel Lucas-González Manuel Viuda-Martos José Ángel Pérez-Álvarez Juana Fernández-López 《Plant foods for human nutrition (Dordrecht, Netherlands)》2017,72(1):67-73
The aim of the work was to study the influence of particle size in the composition, physicochemical, techno-functional and physio-functional properties of two flours obtained from persimmon (Diospyros kaki Trumb. cvs. ‘Rojo Brillante’ (RBF) and ‘Triump’ (THF) coproducts. The cultivar (RBF and THF) and particle size significantly affected all parameters under study, although depending on the evaluated property, only one of these effects predominated. Carbohydrates (38.07–46.98 g/100 g) and total dietary fiber (32.07–43.57 g/100 g) were the main components in both flours (RBF and THF). Furthermore, insoluble dietary fiber represented more than 68% of total dietary fiber content. All color properties studied were influenced by cultivar and particle size. For both cultivars, the lower particle size, the higher lightness and hue values. RBF flours showed high values for emulsifying activity (69.33–74.00 mL/mL), while THF presented high values for water holding capacity (WHC: 9.47–12.19 g water/g sample). The bile holding capacity (BHC) and fat/oil binding values were, in general, higher in RBF (19.61–12.19 g bile/g sample and 11.98–9.07, respectively) than THF (16.12–12.40 g bile/g sample and 9.78–7.96, respectively). The effect of particle size was really evident in both WHC and BHC. Due to their dietary fiber content, techno-functional and physio-functional properties, persimmon flours seem to have a good profile to be used as potential functional ingredient. 相似文献
75.
Celia Carrillo Raquel Rey Marc Hendrickx María del Mar Cavia Sara Alonso-Torre 《Plant foods for human nutrition (Dordrecht, Netherlands)》2017,72(3):266-273
Red beetroot has been ranked among the 10 most potent antioxidant vegetables, although only extraction-based methods have been used to evaluate its total antioxidant capacity. Therefore, the present study aims at comparing the traditional extraction-based method with two more recent approaches (QUENCHER -QUick, Easy, New, CHEap and Reproducible- and GAR -global antioxidant response method), in order to establish their suitability in the case of beetroot. Our results indicate that the total antioxidant capacity of beetroot would be underestimated when using extraction-based procedures, since both QUENCHER and GAR methods resulted in a higher total antioxidant capacity. The effect of a thermal treatment on the total antioxidant capacity of beetroot varies among the methods evaluated and our findings suggest different compounds responsible for the total antioxidant capacity detected in each pre-processing method. Remarkably, the present study demonstrates that the traditional extraction-based method seems useful to screen for (changes in) the “bioavailable” antioxidant potential of the root. 相似文献
76.
Raico E Laria Lamela Yanis Cruz Quintana Raquel Silveira Coffigny Mercedes Martínez Norma González Herrate 《Aquaculture Research》2008,39(12):1316-1321
Formalin is used in shrimp industry to eliminate ectoparasites and as a disinfectant. However, the effect of formalin on shrimp's defense mechanism is unknown. Several biomarkers were used to assess the immune response of juveniles of the shrimp Litopenaeus schmitti exposed to different concentrations of formalin (10, 25 and 50 mg L?1) during 24 and 48 h. Formalin concentrations of 25 and 50 mg L?1 produced a significant reduction in the total haemocyte count at both 24 and 48 h. Peroxidase and phenoloxidase activity did not show variations. The total protein concentration in haemolymph of shrimps was not significantly different between experimental groups. Histological analysis showed hyperplasia in the gills of animals exposed at 10 mg L?1 for 24 h; however, the exposure at 25 and 50 mg L?1 caused necrosis in gills, hepathopancreas and the antennal gland. 相似文献
77.
78.
Yasunori SHINOZUKA Naoki SUZUKI Sohei KANEKO Kazuhiro KAWAI Tomomi KURUMISAWA Yuko SHIMIZU Tadashi IMANISHI Ayumu OHNO Mano TAKAHASHI Naoki ISOBE 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2022,84(3):310
The purpose of this study was to determine the concentrations of antimicrobial components (immunoglobulin A (IgA), lactoferrin (LF), lingual antimicrobial peptide (LAP), and S100A7) in normal milk and their relation to host factors (Age, somatic cell count (SCC), days in milk, richness, and alpha diversity of the milk microbiota) in dairy cows using multivariate regression tree analyses, and to clarify how the milk microbiota is related to the obtained results. Thirty normal milk samples were collected from a commercial dairy farm in June 2020. The thresholds that predicted the concentration of each antimicrobial component in milk were obtained by regression tree analysis, and the beta-diversity of the milk microbiota composition between groups divided according to each threshold was compared by an analysis of similarities test. The IgA and LF concentrations were mainly predicted by the SCC (177,500 and 70,000 cells/ml, respectively), and the LAP and S100A7 concentrations were predicted by Age (29.667 and 40.3 months, respectively). No relationship was observed between the concentration of IgA, LAP, or S100A7 and the milk microbiota composition between the groups divided by the threshold for prediction, but the milk microbiota composition was significantly different between the groups divided by the threshold for predicting the LF concentration. Our results indicated that the LF concentration in normal milk may be associated with the milk microbiota composition. 相似文献
79.
Sanchez R Vázquez A Riquelme D Villén J 《Journal of agricultural and food chemistry》2003,51(21):6098-6102
A fully automated on-line reversed phase liquid chromatography-gas chromatography system is described. The system uses a prototype of the automated through oven transfer adsorption desorption interface. The system is demonstrated by presenting a new rapid method for the determination of pesticide residue in olive oil, which is injected directly with no sample pretreatment step other than filtration. Methanol:water is used as the eluent in the LC preseparation step, while the LC fraction containing the pesticide is automatically transferred to the gas chromatograph. Detection limits of pesticides varied from 0.18 to 0.44 mg/L when a flame ionization detector was used. As an example, relative standard deviation and linear calibration are presented for terbutryne. 相似文献
80.
T Tsubota H Kanagawa K Yamamoto T Mano M Yamanaka I Kita T Tiba 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1992,54(1):1-5
Serum progesterone (P) concentrations using P-EIA kit (Ovucheck, Cambridge Life Science Co., Ltd.) were examined in 8 captive and 7 free-ranging female Hokkaido brown bears (Ursus arctos yesoensis). The intra- and inter-assay coefficients of variation were 8.9%, 12.6% and 16.6%, 22.7%, respectively, based on 2 serum samples. There was a significant correlation between EIA and radioimmunoassay results based on 64 serum samples (r = 0.725; p less than 0.01). Serum P concentrations were examined in 5 pregnant, 2 solitary non-pregnant bears and a lactating non-pregnant bear in captivity. Annual changes of P levels in pregnant bears were observed as a small elevation during the mating season (May-June), a re-elevation in September-October and a sharp elevation in November-December. The sharp elevation was suspected to reflect changes when implantation occurred. Annual changes of P levels in solitary non-pregnant bears were similar to those in pregnant bears. An annual change of P levels in a lactating non-pregnant bear maintained levels under 5 ng/ml. Two of 7 free-ranging bears exhibited P levels over 1 ng/ml and the birth of cubs was confirmed in the following year in 1 of the 2 bears. P concentrations of other free-ranging bears exhibited less than 1 ng/ml, and these bears were considered to be non-pregnant. It was concluded that P-EIA kit was available for measuring P concentrations in Hokkaido brown bears. 相似文献