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排序方式: 共有677条查询结果,搜索用时 15 毫秒
521.
Martina agalj Danijela Skroza María del Carmen Razola-Díaz Vito Verardo Daniela Bassi Roberta Frleta Ivana Generali Mekini Giulia Tabanelli Vida imat 《Marine drugs》2022,20(1)
The underexplored biodiversity of seaweeds has recently drawn great attention from researchers to find the bioactive compounds that might contribute to the growth of the blue economy. In this study, we aimed to explore the effect of seasonal growth (from May to September) on the in vitro antioxidant (FRAP, DPPH, and ORAC) and antimicrobial effects (MIC and MBC) of Cystoseira compressa collected in the Central Adriatic Sea. Algal compounds were analyzed by UPLC-PDA-ESI-QTOF, and TPC and TTC were determined. Fatty acids, among which oleic acid, palmitoleic acid, and palmitic acid were the dominant compounds in samples. The highest TPC, TTC and FRAP were obtained for June extract, 83.4 ± 4.0 mg GAE/g, 8.8 ± 0.8 mg CE/g and 2.7 ± 0.1 mM TE, respectively. The highest ORAC value of 72.1 ± 1.2 µM TE was obtained for the August samples, and all samples showed extremely high free radical scavenging activity and DPPH inhibition (>80%). The MIC and MBC results showed the best antibacterial activity for the June, July and August samples, when sea temperature was the highest, against Listeria monocytogenes, Staphylococcus aureus, and Salmonella enteritidis. The results show C. compressa as a potential species for the industrial production of nutraceuticals or functional food ingredients. 相似文献
522.
523.
David E. Johnson Sin E. Rees Daniela Diz Peter J.S. Jones Callum Roberts Christopher Barrio Frojn 《水产资源保护:海洋与淡水生态系统》2019,29(Z2):181-194
- 相似文献
524.
Gsta Baganz Daniela Baganz Georg Staaks Hendrik Monsees Werner Kloas 《Aquaculture Research》2020,51(7):2711-2724
This case study examined the productivity and economic performance of a double recirculation aquaponic system in Germany with a total interior area of about 540 m2. Calculations were carried out as an ex post analysis based on one‐year production data. The initial situation was not profitable; therefore, two scenarios were developed, which envisaged a significantly improved productivity of the fish as well as of the plant unit and a more than threefold enlargement of the greenhouse to make maximum use of the fish effluent. An ex ante analysis was performed and showed that the second scenario was profitable with a payback period of about 12 years. On the basis of this scenario, a simple but comprehensive model case with the complete set of economic key indicators showed that aquaponics is feasible if it exploits its potential, regardless of the high initial investment costs. The model case would cover an overall space of about 2,000 m2, which is suitable for professional aquaponics in urban and peri‐urban areas with their limited space availability. Furthermore, multi‐loop aquaponics with its inherent circles fits into the circular city concept and implements resource‐efficient and sustainable food production into the urban fabric, which is important with increasing urbanization. 相似文献
525.
Daniela Portz Eckhard Koch Alan J. Slusarenko 《European journal of plant pathology / European Foundation for Plant Pathology》2008,122(1):197-206
The volatile antimicrobial substance allicin (diallylthiosulphinate) is produced in garlic when the tissues are damaged and
the substrate allicin (S-allyl-l-cysteine sulphoxide) mixes with the enzyme alliin-lyase (E.C.4.4.1.4). Allicin undergoes thiol-disulphide exchange reactions
with free thiol groups in proteins and it is thought that this is the basis of its antimicrobial action. At 50 μg ml-1, allicin in garlic juice inhibited the germination of sporangia and cysts and subsequent germ tube growth by Phytophthora infestans both in vitro and in vivo on the leaf surface. Disease severity in P. infestans-infected tomato seedlings was also reduced by spraying leaves with garlic juice containing allicin over the range tested
(55–110 μg ml−1) with an effectiveness ranging from approximately 45–100%. Similarly, in growth room experiments at concentrations from 50–1,000 μg
ml−1, allicin in garlic juice reduced the severity of cucumber downy mildew caused by Pseudoperonospora cubensis by approximately 50–100%. These results suggest a potential for developing preparations from garlic for use in specialised
aspects of organic farming, e.g. for reducing pathogen inoculum potential and perhaps for use under glass in horticulture. 相似文献
526.
Daniela Erba Alyssa Hidalgo Jessica Bresciani Andrea Brandolini 《Journal of Cereal Science》2011,54(2):250-254
Trace elements (Zn, Fe, Cu and Mn) and minerals (Ca, Mg, P and K) concentrations were determined in whole meal flour of five einkorn accessions and one bread wheat cultivar, cropped in four different locations for two years. The major factors influencing mineral levels were year and genotype, as well as their interaction. Einkorn varieties exhibited higher Zn (7.18 ± 0.76 mg/100 g DM), Fe (5.23 ± 0.47), Mn (4.65 ± 0.23), Cu (0.90 ± 0.08), Mg (151.2 ± 9.00) and P (541.1 ± 35.37) concentration than bread wheat. Mg concentration correlated positively with that of other bivalent cations (Zn and Ca). The relevant amount of trace elements consistently found in einkorn further confirms the potential of this cereal in human nutrition, either by direct consumption or by introgression of superior alleles into enhanced polyploid wheat cultivars. 相似文献
527.
528.
Daniela Agüeria Pablo Sanzano Paulo Vaz-Pires Edgardo Rodríguez María I. Yeannes 《Journal Of Aquatic Food Product Technology》2013,22(5):708-723
ABSTRACTSensory methods are the most interesting methods to estimate fish quality. Among these, the recently developed quality index method (QIM) has gained popularity, as shown by the multiple publications of QIM schemes in the last years. The objective of this study was to create a new QIM scheme (QIM sensory table and corresponding point system) for the common carp (Cyprinus carpio), basing the definition of the rejection point on sensory, physicochemical (thiobarbituric acid reactive substances, total volatile basic nitrogen, pH, and color measurements), and microbiological criteria (counts of mesophiles, psychrotrophs, and Pseudomonas spp.). A new QIM scheme was developed and is proposed for use in the future; it will be useful for practical evaluations of carp freshness in all steps of the production chain, and it will contribute to a more effective use of the species as an alternative for human food supply. 相似文献
529.
Luisa Garofalo Angela Mastrogiacomo Paolo Casale Rossella Carlini Claudia Eleni Daniela Freggi Donatella Gelli Leyla Knittweis Carmen Mifsud Toni Mingozzi Nicola Novarini Dino Scaravelli Giovanni Scillitani Marco Oliverio Andrea Novelletto 《水产资源保护:海洋与淡水生态系统》2013,23(6):868-884
- that the north Adriatic, the Tunisian continental shelf, the waters around Malta and the Italian Ionian Sea represent important areas for the conservation of rookeries in Greece, Libya and Turkey, respectively;
- that waters off the Italian peninsula and the islands of Lampedusa and Malta are mainly inhabited by individuals of Mediterranean origin, with a major contribution from the nearest and largest colonies, while Atlantic turtles are restricted to the western areas;
- that specific migratory routes exist from rookeries to foraging grounds;
- a poor bi‐parental genetic structuring, which suggests a high male‐mediated gene flow in the Mediterranean;
- mixing of small turtles in waters distant from natal rookeries, and recovery of structuring for large‐sized individuals; and
- that uncommon mtDNA haplotypes are more powerful markers than microsatellite alleles in assessing an individual's origin, owing to their higher geographic specificity.
530.
Divas Karimanzira Karel Keesman Werner Kloas Daniela Baganz Thomas Rauschenbach 《Aquaculture Economics & Management (Blackwell Science)》2013,17(4):470-486
ABSTRACTIn this article, optimal control methods based on a metabolite-constrained fish growth model are applied to the operation of fish production in an aquaponic system. The system is formulated for the twin objective of fish growth and plant fertilization to maximize the benefits by optimal and efficient use of resources from aquaculture. The state equations, basically mass balances, required by the optimization algorithms are given in the form of differential equations for the number of fish in the stock, their average weight as mediated through metabolism and appetite, the water recirculation and waste treatment, hydroponic nutrient requirements and their loss functions. Six parameters, that is, water temperature, flow rate, stock density, feed ration size per fish, energy consumption rate and the quality of food (percentage of digestible proteins) are used to control the system under dynamic conditions. The time to harvest is treated as a static decision variable that is repeatedly adjusted to find the profit-maximizing solution. By modeling the complex interactions between the economic and biological systems, it is possible to obtain the most efficient decisions with respect to diet composition, feeding rates, harvesting time and nutrient releases. Some sample numerical results using data from a tilapia-tomato farm are presented and discussed. 相似文献