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61.
Lippia alba (Verbenaceae) hydrolate as sedative of tambaqui (Colossoma macropomum) juveniles in simulated transport conditions
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Hugo Napoleão Pereira da Silva Elen Monique de Oliveira Sousa Janna Laely dos Santos Maia Mônica Tatiane Lima Pinheiro Soraia Valeria de Oliveira Coelho Lameirão Rosa Helena Veras Mourão José Guilherme Soares Maia Bernardo Baldisserotto Lenise Vargas Flores da Silva 《Aquaculture Research》2018,49(1):128-134
Lippia alba hydrolate (LAH) is produced as a secondary product in essential oil extraction. The objective of this study was to evaluate the use of LAH in a simulation of the transport of tambaqui (Colossoma macropomum) juveniles. A series of 17 hr simulations were performed using load densities of 30, 60 and 90 juveniles per L and four LAH concentrations of 0.4%, 1%, 2% and 5%, with a control of just water. Fish survival, temperature, dissolved oxygen, conductivity, pH, ammonia excretion, alkalinity water hardness and net Na+, K+, Cl‐ fluxes, were all evaluated before and after the transport simulations. Mucous cell densities in the gills were also determined microscopically, post simulation. The results showed that addition of 5% LAH achieved better survival during the simulation than the water control. Dissolved oxygen was significantly lower with an increased load density. Also, conductivity, NH4 excretion and net ionic fluxes (K+ and Cl?) were lower with 5% LAH, although mainly where higher load densities were tested. Mucous cell density was lower in LAH concentrations of 2% and 5%, again with higher load densities. In view of these findings, it is suggested that 5% LAH is an effective sedative for use in the transport of tambaqui, mainly with high load densities. This work is the first study of LAH and highlights its potential applications in aquaculture management. 相似文献
62.
María Sofía Larroulet Estela Noemí Hepper Mónica Patricia Álvarez Redondo Valeria Belmonte Ana María Urioste 《Arid Land Research and Management》2016,30(1):105-119
Before and after a prescribed burning, the upper 2.5 cm of soil in patches of forage, nonforage, and shrub vegetation were sampled. Then, bulk density, gravimetric moisture, pH in water, available phosphorus, exchangeable cations, cationic exchange capacity, total nitrogen, total, particulate, and mineral organic carbon contents were determined. Maximum temperature ranges reached over the ground during burning were measured and the highest values were registered in shrubs. Results showed that total, particulate, and mineral organic carbon and total nitrogen contents and percent base saturation increased in all soils after burning, without detecting differential effects between vegetation patches. After burning, available phosphorus content increased both for forage and shrub patches. A Na+ content decrease was observed for all soils in the different patches while Mg2+ content increased. No changes in the other analyzed variables were observed. Prescribed burning, as studied in the present work, might improve the Caldenal soils’ chemical fertility, mainly due to an increase in labile organic matter and some nutrients essential for plant growth. 相似文献
63.
64.
Delgado María C. Orsini Galleano Mónica Añón María C. Tironi Valeria A. 《Plant foods for human nutrition (Dordrecht, Netherlands)》2015,70(1):27-34
Plant Foods for Human Nutrition - We evaluated the capacity of simulated gastrointestinal digests or alcalase hydrolysates of protein isolates from amaranth to scavenge diverse physiologically... 相似文献
65.
Chiara Nobili Simone D’Angeli Maria Maddalena Altamura Valeria Scala Anna Adele Fabbri Massimo Reverberi Corrado Fanelli 《European journal of plant pathology / European Foundation for Plant Pathology》2014,139(2):423-438
Wheat germinating caryopses may represent a starting point for the Fusarium Head Blight disease; however, only few studies concern the defence repertoire of wheat caryopses against fungal challenge. The germinating caryopses of two wheat commercial varieties (Blasco and Sagittario), differentially susceptible to FHB in the field, were inoculated with F. graminearum and the redox status in the interaction milieu, oxylipin production, the expression profile of some host-defence related genes, and programmed cell death in the aleuronic layer, were analysed. In Sagittario, the redox balance was profoundly modified and 9-oxylipins accumulated during fungal contamination. In this variety, F. graminearum produced a high quantity of deoxynivalenol whilst programmed cell death, also through metacaspases activation, was enhanced in the aleuronic layer of its caryopses. In Blasco, the expression of tolerance factors such as Pathogenesis-Related-protein1, glucosyl-transferase and glutathione transferase genes was up-regulated consequent to infection. Results show that unscavenged ROS and 9-oxylipins may be related to deoxynivalenol accumulation in the germinating caryopses of wheat after F. graminearum infection. 相似文献
66.
The increasing demand for traditional and natural foods has renewed the interest in hulled wheat species. Among these, Triticum dicoccum Schübler has survived in Italy only in a few hilly and mountainous areas of central and southern Italy. As a rule, emmer is cultivated in marginal areas with organic farming procedures that use very low N inputs, since this wild species is characterised by low yield, long and weak culms that easily lodge under windy conditions. Unfortunately, there is a lack of information on crop productivity and N effect for this crop. Research was carried out to study the effect of cultivation year (2004 and 2005), plant origin (Garfagnana, Leonessa and Molise) and N dressing (N0, N30, N60 and N90 kg ha−1) on crop yield and grain quality of emmer grown in south-central Italy. Fertilizer was split at seeding, tillering and stem elongation. Tested parameters were highly influenced either by crop origin or N application (biomass, hulled and threshed grain yield, spikes m−2, spikelets per spike, kernel weight, plant height, lodging, kernel ash and proteins). Several parameters augmented as fertilization rate increased (hulled and unhulled grain yield, biomass accumulation, spikes m−2, kernels m−2, protein content); 1000-kernel weight showed an opposite trend and in some cases no differences were noticed among fertilized treatments (plant height and spikelets per spike). Molise was the most productive population, closely followed by Garfagnana. The present research rejected some common belief that emmer has to be grown without N dressing, and crop undergoes lodging in marginal mountainous areas. Besides, grain yield of N90 and N60 treated emmer was only 6 and 18% lower compared to the five most important durum wheat varieties cultivated in the same area, suggesting emmer as a possible alternative crop to durum wheat in marginal areas of Mediterranean-type agro-ecosystems. 相似文献
67.
Chalinulasterol (1) a new chlorinated sterol disulfate was isolated from the Caribbean sponge Chalinula molitba. Its structure was elucidated using mass spectrometry and NMR experiments. The possible role of chalinulasterol as modulator of the PXR nuclear receptor was investigated but, in spite of the close structural relationship with the PXR agonist solomonsterol A (2), it showed no activity. The structural requirements for the PXR nuclear receptor activity were discussed. 相似文献
68.
Antonia Concetta Elia Valentina Ciccotelli Nicole Pacini Ambrosius Josef Martin Dörr Marilena Gili Mauro Natali Laura Gasco Marino Prearo Maria Cesarina Abete 《Fish physiology and biochemistry》2014,40(4):1055-1068
Oxytetracycline (OTC) is employed in fish farms to contest or prevent bacterial infections. We simulated an OTC treatment at therapeutic level (75 mg kg?1) and at higher doses (150, 300 mg kg?1) for 10 days. A withdrawal period of 10 days was considered for treated carp, carrying out the same chemical and biochemical analyses (total glutathione, superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, glutathione S-transferase and malondialdehyde). The aim was to obtain data related to the carryover in muscle and on variations in the antioxidant indicators in liver and kidney. The OTC residual levels in muscle showed a dose–response relationship. After 10 days of treatment at the recommended dose (75 mg kg?1), the mean value in muscle was 295 μg kg?1. After 10 withdrawal days, residues in all treated groups were not entirely eliminated by fish. Residues of recommended 75 mg kg?1 OTC dose were lower than the maximum permitted by EEC regulation: 100 μg kg?1. Disturbance in the antioxidant systems in liver and kidney was recorded in (150, 300 mg kg?1) carp, as well as during the withdrawal period. A lowered superoxide dismutase activity and higher levels of catalase, glutathione peroxidase, glutathione reductase and glutathione were evaluated in liver, while in kidney only higher malondialdehyde and glutathione S-transferase concentrations were recorded for 300 mg kg?1 dose. The therapeutic OTC dose exerted lower effects, and only in liver, enhancement of GPx and GR activities was recorded. After the withdrawal period, altered antioxidant responses in tissues were restored for all three OTC doses. 相似文献
69.
María Susana Fortunato Sabina Baroni Ana Julieta González Jesús David Álvarez Roncancio Mariana Papalia Manuela Martinefsky Valeria Trípodi Estela Planes Alfredo Gallego Sonia Edith Korol 《Water, air, and soil pollution》2018,229(4):120
Biodegradability of chlorhexidine (CH), triclosan (TC), and benzalkonium chloride (CBA) has been tested in 18 surface water sampling points in the urban area of Buenos Aires. Sampling points were located in both the Reconquista and the Matanza-Riachuelo basins as well as in the La Plata River. High tolerance to the three disinfectants was found and indigenous strains capable of degrading CBA and TC were isolated. Neither tolerance nor biodegradation were correlated with sewage pollution. A strain that degrades CBA was identified as belonging to the genus Pseudomonas using the API20NE system and 16SRNA sequencing. In batch assays, the strain was capable of degrading 100, 200, and up to 500 mg L?1 of CBA in 10, 25, and 46 h respectively with specific growth rates (μ) of 0.56, 0.30, and 0.14 h?1. The efficiency of the process was between 99.5–98.0% in terms of compound removal and between 93.8–89.1% in terms of chemical oxygen demand (COD). The detoxification of the compound as a result of the biodegradation was assessed using Pseudokirchneriella subcapitata, Vibrio fischeri, and Lactuca sativa as test organisms. 相似文献
70.
Claudio Zaccone Valeria D’Orazio William Shotyk Teodoro M. Miano 《Journal of Soils and Sediments》2009,9(5):443-456