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1.
Chemical composition of Lippia spp. essential oil and antimicrobial activity against Aeromonas hydrophila 下载免费PDF全文
Cláudia Majolo Silvia Imaculada Barros da Rocha Edsandra Campos Chagas Francisco Célio Maia Chaves Humberto Ribeiro Bizzo 《Aquaculture Research》2017,48(5):2380-2387
Phytotherapy can replace antibiotic administration as an alternative to control Aeromonas hydrophila, one of the main bacteria involved in the aetiology of farmed fish diseases. Given that plants of the Lippia spp. genus show biological potential for antimicrobial activity, this study evaluated the chemical composition of essential oils extracted from Lippia alba, Lippia origanoides and Lippia sidoides and their activity against A. hydrophila. The oils were obtained by steam distillation in a Clevenger‐type apparatus and their composition determined by gas chromatography and mass spectrometry (CG/MS). Antibacterial activity was assessed by calculating the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) using broth microdilution method. The main compounds identified were geranial (25.4%) and neral (16.6%) in L. alba oil, carvacrol (40.4%) and p‐cymene (11.4%) in L. origanoides oil and thymol (76.6%) and ortho‐cymene (6.3%) in L. sidoides oil. The three Lippia species showed bacteriostatic and bactericidal action against A. hydrophila, with MICs and MBCs ranging from 1250 to 5000 μg mL?1. Of the species tested, the best performance was obtained with essential oil of L. sidoides. 相似文献
2.
Andreia I. G. Raposo Susana M. F. Ferreira Rodolfo Ramos Pedro M. Santos Catarina Anjos Teresa Baptista Carla Tecelo Jos L. Costa Ana Pombo 《Aquaculture Research》2019,50(8):2023-2038
In this study, the effects of three diets were investigated to enhance Paracentrotus lividus production for commercial purposes. P. lividus were fed ad libitum for 80 days with: diet A—fresh Codium tomentosum Stackhouse, 1797; diet B—formulated using a jellified mix of macroalgae and vegetables, including C. tomentosum (20%), Coralina sp. Linnaeus, 1758 (17%), cabbage Brassica oleracea var. capitata Linnaeus, 1753 (30%), carrot Daucus carota Linnaeus, 1753 (30%) and agar (3%) as a gelling agent. Diet C consisted of maize Zea mays Linnaeus, 1753 (56%) and New Zealand spinach Tetragonia tetragonoides (Pallas, 1781) Kuntze, 1891 (44%). Their effects on the gonadal and somatic growths, gonadosomatic index (GI) and gametogenesis were evaluated, as well as on the total lipid content and fatty acid composition of sea urchin's gonads. Diet A provided high values of eicosapentaenoic acid (EPA). Gonads of sea urchins fed with diet A were found mostly in growth and maturation stages of gametogenesis and showed the lowest lipid content. Sea urchins fed with diet B presented their gonads in the reabsorption stage and had the highest values of omega‐3 polyunsaturated fatty acids (PUFAs). Sea urchins fed with diet C were in the early stages of gametogenesis and had the highest values of lipid content, plus omega‐6 PUFAs. Once as an ingredient in a balanced mix with vegetables, C. tomentosum can be a key factor to the development of new promising high‐quality and low‐cost feed for P. lividus roe enhancement. 相似文献
3.
Kennya Gomes Silva Addam Scheila Anelise Pereira Gabriel Fernandes Alves Jesus Lucas Cardoso Nichola Syracuse Gustavo Ruschel Lopes Nicollas Breda Lehmann Bruno Correa da Silva Lúvia Souza de S Francisco Clio Maia Chaves Maurício Latera Martins Jos Luiz Pedreira Mourio 《Aquaculture Research》2019,50(10):2960-2971
This study evaluated the effects of dietary supplementation of organic acids blend (OAB) alone or in combination with essential oil, Lippia origanoides (OAE) for Nile tilapia fed supplemented diets for 30 days. Fish (1.1 ± 0.04 g) were fed control (Control), or OAB 0.5% or OAB 0.5% + essential oil 0.125% (OAE) respectively. At the end of the experiment, samples were collected for de hemato‐immunological, histological analysis of the intestine and liver, as well as microbiology of the intestine. The pH of the diets supplemented with OAB and OAE reduced 0.92 and 0.19 respectively. The growth and FCR were unaffected by the treatments, but survival was significantly higher in the OAB treatment. Fish fed the OAB diet showed reduced concentration of total heterotrophic bacteria and Pseudomonas sp. in the intestine. Increased glucose in fish fed OAB and high number of circulating monocytes in fish fed OAE diet were observed. The anterior intestine of fish fed OAE diet showed larger number of goblet cells and increased villi height. The diet supplemented with OAB, mainly, improved the intestinal health and survival of tilapia juveniles and can be used in juvenile production. 相似文献
4.
Felipe Nogueira Soares Maria Emilia Franco Oliveira Luciana Cristina Padilha-Nakaghi Luís Guilherme de Oliveira Marcus Antônio Rossi Feliciano Felipe Brener Bezerra de Oliveira Pedro Paulo Maia Teixeira Wilter Ricardo Russiano Vicente Cristian Faturi Luiz Fernando de Souza Rodrigues 《Tropical animal health and production》2015,47(8):1465-1471
5.
The ethanolic extract of the fruit bark from Magonia glabrata yielded shikimic acid, scopoletin, sitosterol glycoside and 2-O-methyl-l-inositol. Antioxidant, icthyotoxicity and brine shrimp lethality activities were observed in this extract. The major constituent, 2-O-methyl-l-inositol, was found to be inactive in two assays but showed moderate activity as a radical scavenger. 相似文献
6.
Jorge Miguel Silva Faria Inês Sena Bruno Ribeiro Ana Margarida Rodrigues Carla Maria Nobre Maleita Isabel Abrantes Richard Bennett Manuel Mota Ana Cristina da Silva Figueiredo 《Journal of pest science》2016,89(1):207-217
The Columbia root-knot nematode (CRKN), Meloidogyne chitwoodi, is an EPPO A2 type quarantine pest since 1998. This nematode causes severe damage in economically important crops such as potato and tomato, making agricultural products unacceptable for the fresh market and food processing. Commonly used nematicidal synthetic chemicals are often environmentally unsafe. Essential oils (EOs) may constitute safer alternatives against RKN. EOs, isolated from 56 plant samples, were tested against CRKN hatching, in direct contact bioassays. Some of the most successful EOs were fractionated and the hydrocarbon molecules (HM) and oxygen-containing molecules (OCM) fractions tested separately. 24 EOs displayed very strong hatching inhibitions (≥90 %) at 2 µL mL?1 and were further tested at lower concentrations. Dysphaniaambrosioides, Filipendula ulmaria, Ruta graveolens, Satureja montana and Thymbra capitata EOs revealed the lowest EC50 values (<0.15 µL mL?1). The main compounds of these EOs, namely 2-undecanone, ascaridol, carvacrol, isoascaridol, methyl salicylate, p-cymene and/or γ-terpinene, were putatively considered responsible for CRKN hatching inhibition. S. montana and T. capitata OCM fractions showed hatching inhibitions higher than HM fractions. The comparison of EO and corresponding fractions EC50 values suggests interactions between OCM and HM fractions against CRKN hatching. These species EOs showed to be potential environmentally friendly CRKN hatching inhibitors; nonetheless, bioactivity should be considered globally, since its HM and OCM fractions may contribute, diversely, to the full anti-hatching activity. 相似文献
7.
Rauter AP Filipe MM Prata C Noronha JP Sampayo MA Justino J Bermejo J 《Fitoterapia》2005,76(5):433-438
Diacronema sp. was cultured and its sterols were separated by column chromatography on silica gel. The new sterol 24-ethyl-4alpha-methyl-cholestane-3,20-diol (1) was characterised by NMR and MS spectrometry, as well as (22E)-24-ethyl-4alpha-methyl-5alpha-cholest-22-en-3beta-ol (2) and beta-sitosterol, the major components of the sterol fractions. Neither the biosynthetic origin of the new dihydroxysterol nor its role in the biochemistry of Diacronema is known. 相似文献
8.
Carla Bacchetta Andrea S. Rossi Raúl E. Cian Silvina R. Drago Jimena Cazenave 《Aquaculture Nutrition》2019,25(4):761-769
This study was conducted to investigate the effects of dietary synthetic β‐carotene on growth performance, haematological and immunological parameters, energy reserves and antioxidant status of juvenile fish Piaractus mesopotamicus. Two hundred and ten fish (12.24 ± 2.98 g) were fed with a control extruded feed (CEF) and the same diet supplemented with β‐carotene (BEF) for 90 days. A higher weight gain and specific growth rate were found in fish fed BEF in comparison with those fed CEF. In addition, BEF‐fed fish showed lower liver somatic index and a higher percentage of eosinophils. No statistical differences were found in energy reserves, except for plasma triglycerides which decreased in fish fed with BEF. Regarding oxidative stress markers, decreased activities of antioxidant enzymes were found in intestine and gills of BEF‐fed fish (SOD and GST, respectively). In the liver, both LPO levels and CAT activity decreased in fish fed with BEF. Additionally, lower brain LPO levels without changes in the antioxidant enzymes were observed in BEF‐fed fish. The inclusion of dietary synthetic β‐carotene improved growth and antioxidant status, and had a plasma triglyceride‐lowering effect in juvenile P. mesopotamicus. 相似文献
9.
Tiago Edu Kaspary Luan Cutti Rafael Schwalm Rafaeli Carla Andrea Delatorre Aldo Merotto Jr 《Weed Research》2020,60(6):435-449
Evolution of flooding tolerance in weedy rice has occurred in several rice-growing regions, but the genes related to this process and the environmental effects are unknown. The objective of this study was to analyse the expression of genes related to flooding tolerance in response to temperature and flooding during the initial establishment of weedy rice. The experiments were carried out with rice cultivars IRGA 417 and Nipponbare, which are sensitive to flooding, and weedy rice ITJ03 and AV04 genotypes that have high and intermediate tolerance to flooding, respectively. The expression of genes related to reserve mobilisation, anaerobic respiration, escape and quiescence strategies was analysed at periods up to 24 days after sowing. The flooding tolerance of weedy rice genotype ITJ03 was associated with the expression of RAmy3D and OsTPP7 , which are involved in the mobilisation of carbohydrate reserves, ADH1 and ADH2, which participate in anaerobic respiration, and SNRKL1 that triggers rapid elongation of the coleoptile and emergence. Although the genes PDC1, SUS3 and SUB1 are important for flooding tolerance in cultivated rice, their expression was not directly related to flooding tolerance in weedy rice. A temperature of 20°C reduced levels of expression of the RAmy3D, ADH2 and SNRKL1 genes and low temperature had a negative effect on the establishment of weedy rice. Breeding of rice genotypes with tolerance of low temperatures and anaerobic conditions may be a viable strategy to improve the control of weedy rice in paddy fields. 相似文献
10.