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排序方式: 共有306条查询结果,搜索用时 406 毫秒
301.
Bernardo M. M. N. Borges Matheus Sampaio C. Barreto Paulo S. Pavinato Henrique C. J. Franco João Luís Nunes Carvalho Mathias Strauss Saran Sohi 《European Journal of Soil Science》2023,74(4):e13400
Innovation is required on many fronts in agriculture, not only to improve nutrient use efficiency but also to mitigate the effects of climate change. Our previous studies presented the high agronomic efficiency of an experimental phosphate fertilizer using a biochar-matrix, called ‘BioFert’. However, the efficiency of BioFert for soil carbon sequestration goals has not yet been evaluated. We incubated BioFert and initial raw sugarcane-biochar over 56 days in two soils (i.e., Ferralsol and Alisol) and measured the total CO2 and δ13C-CO2 to quantify the contribution of native soil organic matter, sugarcane-biochar, or BioFert to carbon mineralization. There was no significant difference in cumulative CO2 release between BioFert and the control (without carbon addition), and BioFert was less mineralized than carbon from sugarcane-biochar regardless of soil type. In addition, accelerated aging by thermal oxidation of these carbon sources revealed that more than 80% of BioFert-carbon was prevented from accelerated mineralization, while sugarcane-biochar achieved ~80% of carbon mineralization. The residual solids after oxidation were analysed by X-ray photoelectron spectroscopy and indicated aliphatic/aromatic and carboxylic chemical bonds on the BioFert surface, which might offer new cation exchange sites over time. We conclude that BioFert is not only a phosphate fertilizer with high phosphorus use efficiency but also a stable source of carbon for soil carbon sequestration purposes. 相似文献
302.
Oliveira DF Pereira AC Figueiredo HC Carvalho DA Silva G Nunes AS Alves DS Carvalho HW 《Fitoterapia》2007,78(2):142-145
A screening was conducted with 26 plants collected in the Brazilian southeast region, to identify plant extracts with antibacterial properties against Aeromonas hydrophila, Bacillus subtilis, Pseudomonas aeruginosa and Staphylococcus aureus. Initially, the agar diffusion method was employed. Then, those extracts presenting activity were submitted to a broth microdilution assay to determine the minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC). It was observed that 13 of the tested extracts showed antibacterial activity. The best results were obtained with those from Lantana lilacina and Phyllanthus tenellus. 相似文献
303.
Bruno Bianch Loureiro Fernanda Rodrigues Goulart Fernanda Teixeira Macagnan Sharine Nunes Descovi Naglezi de Menezes Lovatto Thais Soares dos Santos Marina Osmari Dalcin Leila Picolli da Silva 《Aquaculture Nutrition》2019,25(5):1115-1123
The aim of this study was to assess the effect of increasing inclusion levels (100, 150, 200 and 300 g/kg) of rice bran protein concentrate (RBPC) in jundiá (Rhamdia quelen) diets using growth, body composition, somatic indices and digestive enzyme activity as parameters. Five isoproteic (370.08 ± 0.04 g/kg) and isocaloric (13.38 ± 0.04 MJ/kg) diets were formulated with four replicates per treatment. After acclimation, 500 jundiá juveniles (initial mean weight of 6.28 ± 0.12 g) were distributed into 20 round polyethylene tanks (280 L) (25 fish per tank) coupled to a thermoregulated water recirculating system. The fish were fed experimental diets three times daily (at 9:00, 13:00 and 17:00 hr) to apparent satiation. At the end of the trial (45 days), no significant differences were found in the body chemical composition, somatic indices, and trypsin and chymotrypsin enzymes of the fish fed experimental diets. A lower final weight and a lower condition factor were found in fish fed diets RBPC10 (100 g/kg of RBPC) and RBPC15 (150 g/kg of RBPC). Based on the results of this study, it is clear that the use of RBPC (at high dietary inclusion levels of 200 and 300 g kg?1) is an effective alternative protein source to fishmeal. 相似文献
304.
Osnan Lennon Lameira Silva Antnia Rafaela Gonalves Macedo Emília do Socorro Conceio de Lima Nunes Keila Diniz Campos Leiliane Cristina Cardoso Araújo Xenna Tiburo Anne Suellen Oliveira Pinto Maria Regina Sarkis Peixoto Joele Micheli da Silva Ferreira Ana Carolina Ramos da Silva Renata Santana Lorenzo Raices Adriano Gomes da Cruz Leandro Juen Rossineide Martins da Rocha 《Aquaculture Research》2020,51(6):2336-2348
The objective of this study was to evaluate the effect of environmental factors on the fatty acid profiles and physicochemical composition of Crassostrea gasar cultured in two locations with differences in salinity and precipitation gradients. The study period was divided into four seasonal divisions—the rainy–dry transition period, the dry season, dry–rainy transition and the rainy season. The salinity, pH and temperature were measured at each site during specimen collection. A total of 712 oyster samples were used for fatty acid profiling and physicochemical analysis. Salinity and precipitation were the environmental parameters that influenced the fatty acid profile and physicochemical characteristics of oysters. C. gasar exhibited excellent values of n3 polyunsaturated fatty acids (DHA, EPA and eicosatrienoic), with a predominance of these acids during periods of higher precipitation. Variations in precipitation and salinity resulted in significant differences in oyster nutritional characteristics. Oysters grown in Amazonian estuaries can be considered nutritious throughout the year, with better conditions during the rainy season. 相似文献
305.
Y. Durmaz M. Donato M. Monteiro L. Gouveia M. L. Nunes T. Gama Pereira Ş. Gökpınar N. M. Bandarra 《Aquaculture International》2009,17(4):391-399
Diacronema vlkianum was grown in polyethylene bags at two different temperatures (18 and 26°C) in the laboratory. The biochemical composition
level decreased when the temperature increased from 18 to 26°C. The maximum cell number at 18°C was 11.9 × 106 cells ml−1, while maximum cell number at 26°C was 1.6 × 106 cells ml−1. The maximum level of α-tocopherol was 257.7 ± 21.6 μg g−1 dry weight (DW) at 18°C. The highest total carotenoids and chlorophylls were 6.5 mg g−1 DW and 4.3 mg g−1 DW, respectively, and the main pigments were determined as astaxanthin and lutein. Polyunsaturated fatty acids were found
to be the predominant group, reaching 39.5% of the total fatty acids at 18°C. This comprised 20:5(n − 3) as the main polyunsaturated
fatty acids (20.4%, at 18°C) followed by 22:6(n − 3) (4.8%, at 18°C). The results suggest that D. vlkianum can be successfully used as feed in shellfish hatcheries or aquaculture hatcheries, either as a substitute or in association
with other microalgae, when this algae is cultured at 18°C. 相似文献
306.
Alessia Caso Fernanda Barbosa da Silva Germana Esposito Roberta Teta Gerardo Della Sala Laura P. A. Nunes Cavalcanti Alessandra Leda Valverde Roberto Carlos C. Martins Valeria Costantino 《Marine drugs》2021,19(12)
Porifera, commonly referred to as marine sponges, are acknowledged as major producers of marine natural products (MNPs). Sponges of the genus Phorbas have attracted much attention over the years. They are widespread in all continents, and several structurally unique compounds have been identified from this species. Terpenes, mainly sesterterpenoids, are the major secondary metabolites isolated from Phorbas species, even though several alkaloids and steroids have also been reported. Many of these compounds have presented interesting biological activities. Particularly, Phorbas sponges have been demonstrated to be a source of cytotoxic metabolites. In addition, MNPs exhibiting cytostatic, antimicrobial, and anti-inflammatory activities have been isolated and structurally characterized. This review provides an overview of almost 130 secondary metabolites from Phorbas sponges and their biological activities, and it covers the literature since the first study published in 1993 until November 2021, including approximately 60 records. The synthetic routes to the most interesting compounds are briefly outlined. 相似文献