Maize (Zea mays L.) genetic factors for preventing fumonisin contamination     

Butrón A  Santiago R  Mansilla P  Pintos-Varela C  Ordas A  Malvar RA 《Journal of agricultural and food chemistry》2006,54(16):6113-6117

Fusarium moniliforme and Fusarium proliferatum are the most frequently isolated fungi from maize (Zea mays L.) in Spain. Both Fusarium species produce toxins potentially dangerous for animals and humans, the fumonisins being the most significant of those toxins. White maize is preferred for human consumption, and extra care should be taken to avoid kernel mycotoxin contamination. The objectives of this study were to identify and quantify kernel infection by Fusarium spp. and contamination by fumonisin on white maize hybrids, to search for white maize sources of resistance to infection by Fusarium spp. and mycotoxin contamination, and to preliminarily study the genetics involved in such resistances. Ten F(1) single crosses derived from a diallel mating design among five white maize inbreds were evaluated in a randomized complete block design with three replications in 2002 at two locations. Fusarium verticilloides and F. proliferatum were detected on kernels of white maize hybrids cultivated in northwestern Spain. No differences in fungal infection were found among maize genotypes, but differences in fumonisin contamination were significant and could be related, in part, to differences in husk tightness. Among the genotypes studied, general combining ability (GCA) effects were the most important for resistance to fumonisin contamination. Inbreds EP10 and EC22 showed the most favorable GCA effects for husk tightness and fumonisin content, and the cross between them, EP10 x EC22, had the most favorable specific combining ability (SCA) effect for husk tightness. Inbreds EP10 and EC22 showed favorable GCA effects for fumonisin contamination and husk tightness, and the cross EP10 x EC22 was the only one with an average fumonisin level below 1 mug/g. Although this should be confirmed with more extensive studies, white maize inbreds developed from white maize landraces could be sources of resistance to fumonisin contamination.  相似文献   

Vapor-phase activities of cinnamon, thyme, and oregano essential oils and key constituents against foodborne microorganisms   总被引：1，自引：0，他引：1  

López P  Sanchez C  Batlle R  Nerín C 《Journal of agricultural and food chemistry》2007,55(11):4348-4356

The aim of the study presented here was to gain knowledge about the vapor-phase antimicrobial activity of selected essential oils and their major putatively active constituents against a range of foodborne bacterial and fungal strains. In a first step, the vapor-phase antimicrobial activities of three commercially available essential oils (EOs)-cinnamon (Cinnamomum zeylanicum), thyme (Thymus vulgaris), and oregano (Origanum vulgare)-were evaluated against a wide range of microorganisms, including Gram-negative bacteria (Escherichia coli, Yersinia enterocolitica, Pseudomonas aeruginosa, and Salmonella choleraesuis), Gram-positive bacteria (Listeria monocytogenes, Staphylococcus aureus, Bacillus cereus, and Enterococcus faecalis), molds (Penicillium islandicum and Aspergillus flavus), and a yeast (Candida albicans). The minimum inhibitory concentrations (MICs) were generally lower for oregano EO than for the thyme and cinnamon EOs, especially against the relatively resistant Gram-negative. The persistence of the EOs' antimicrobial activities over time was assessed, and changes in the composition of the atmosphere they generated over time were determined using single-drop microextraction (SDME) in combination with gas chromatography-mass spectrometry (GC-MS) and subsequent analysis of the data by principal component analysis (PCA). More relevant chemicals were selected. In addition, the vapor-phase activities of putatively key constituents of the oils were screened against representative Gram-positive (L. monocytogenes) and Gram-negative (S. choleraesuis) bacteria, a mold (A. flavus), and a yeast (C. albicans). Of the tested compounds, cinnamaldehyde, thymol, and carvacrol showed the strongest antimicrobial effectiveness, so their MICs, defined as the minimum vapor concentrations that completely inhibited detectable growth of the microorganisms, were calculated. To check for possible interactions between components present in the EOs, cinnamon EO was fortified with cinnamaldehyde and thyme EO with thymol, and then the antimicrobial activities of the fortified oils were compared to those of the respective unfortified EOs using fractional inhibitory concentration (FIC) indices and by plotting inhibition curves as functions of the vapor-phase concentrations. Synergistic effects were detected for cinnamaldehyde on A. flavus and for thymol on L. monocytogenes, S. choleraesuis, and A. flavus. In all other cases the fortification had additive effects, except for cinnamaldehyde's activity against S. choleraesuis, for which the effect was antagonistic. Finally, various microorganisms were found to cause slight changes over time to the atmospheres generated by all of the EOs (fortified and unfortified) except the fortified cinnamon EO.  相似文献   

Detection of Bemisia tabaci Mediterranean cryptic species on soybean in São Paulo and Paraná States (Brazil) and interaction of cowpea mild mottle virus with whiteflies     

Vinicius Henrique Bello  Felipe Barreto da Silva  Luís Fernando Maranho Watanabe  Eduardo Vicentin  Cristiane Muller  Regiane Cristina Oliveira de Freitas Bueno  Jessica Costa Santos  Bruno Rossitto De Marchi  Angélica Maria Nogueira  Valdir Atsushi Yuki  Julio Massaharu Marubayashi  Maria Márcia Pereira Sartori  Marcelo Agenor Pavan  Murad Ghanim  Renate Krause-Sakate 《Plant pathology》2021,70(6):1508-1520

Since the detection of Bemisia tabaci Middle East-Asia Minor 1 (MEAM1) species in Brazil in the early 1990s, this whitefly has been the predominant species and the main viral vector in the country. In this work, whiteflies were collected from commercial soybean fields near and far from greenhouses where Mediterranean (MED) species had previously been detected infesting vegetable crops. Results indicated that MEAM1 was the predominant whitefly species in soybean in most sampling sites, while MED was found colonizing soybean plants in open field conditions alone and/or with MEAM1 in several places. Among the tested insects, MED species was mostly detected harbouring the facultative endosymbiont Hamiltonella. We also detected cowpea mild mottle virus (CPMMV) infecting soybean plants. Transmission assays demonstrated that MED species was more efficient transmitting CPMMV from beans to beans and from soybean to soybean plants than MEAM1, while MEAM1 was more efficient in transmitting the virus from soybean to bean than MED. Performance assays indicated that adult emergence of both species on CPMMV-infected soybean plants was higher when compared with the emergence on healthy plants. Moreover, nonviruliferous MED and MEAM1 adults preferred to settle more often on healthy plants, while viruliferous adults settled more often on CPMMV-infected soybean plants. As MED has already been found in soybean open fields in São Paulo and Paraná States, Brazil, and it is a good vector of CPMMV, we anticipate problems related to whitefly management and to increase in the incidence of the virus in soybean.  相似文献   

Aligning landscape structure with ecosystem services along an urban–rural gradient. Trade-offs and transitions towards cultural services     

Herrero-Jáuregui  Cristina  Arnaiz-Schmitz  Cecilia  Herrera  Lorena  Smart  Simon M.  Montes  Carlos  Pineda  Francisco D.  Schmitz  Maria Fe 《Landscape Ecology》2019,34(7):1525-1545

Landscape Ecology - Urban–rural gradients provide a suitable framework for studying the provision of urban and rural ecosystem services (ES), linked to social welfare. Landscape structure...  相似文献   

The role of job uncertainty in inter‐regional commuting: The case of Italy     

Angela Parenti  Cristina Tealdi 《Growth and change》2019,50(2):634-671

This paper studies the evolution of the determinants of inter‐regional commuting in Italy in the period 1992–2016, during which the labour market has been significantly reformed. To capture the changes in commuting patterns, the analysis of the role of individual, job, firm, and regional characteristics is performed. Specifically, the focus is on the impact of job uncertainty at both micro and macro level, through the analysis of the way the diffusion of temporary contracts has affected the decision to commute for work. The findings suggest that in more recent years workers hired on a temporary contract are more likely to commute to another region. Moreover, the higher the relative share of temporary contracts in the region of residence, the higher the probability of commuting across regions. These findings support the idea that the strong utilisation of (short) temporary contracts represents a push factor, which drives workers away in search of better job opportunities, with potentially negative consequences for poorly performing regions.  相似文献   

Effect of Steeping Corn with Lactic Acid on Starch Properties     

Mnica Haros  Oscar E. Perez  Cristina M. Rosell 《Cereal Chemistry》2004,81(1):10-14

Pasting and thermal properties of starch from corn steeped in the presence of lactic acid and at different steeping times (8, 16, 24, 32, and 40 hr) were investigated. Corn kernels were steeped at 52°C with 0.2% (w/v) SO₂ and with and without 0.5% (v/v) lactic acid. The isolated starch obtained by corn wet‐milling was characterized by determining starch recoveries, retrogradation, and melting transition properties of the lipid‐amylose complex by differential scanning calorimetry (DSC), and pasting properties by the Rapid Visco Analyser (RVA). Damaged granules and the starch granule size were determined by using microscopic techniques. Starches from corn steeped in the presence of lactic acid (LAS) were compared with control starch (CS) steeped without lactic acid. Greater starch recoveries were obtained for LAS samples than for CS samples, and practically no damaged starch was present in the former preparations. The presence of lactic acid affected the RVA profiles and steeping time affected the viscosities of the starch suspensions. In general, the RVA parameters of LAS suspensions were lower than those of CS suspensions. No great modification of the thermal properties was observed; only a slight decrease in amylopectin retrogradation and in the melting enthalpy of the amylose‐lipid complex was observed. Hydrolysis of the starch during steeping seems the most probable explanation to the starch modifications produced by lactic acid addition.  相似文献   

Essential fish habitats and hotspots of nekto‐benthic diversity and density in the western Mediterranean     

M. Pilar Tugores  Francesc Ordines  Beatriz Guijarro  Cristina García‐Ruíz  Antonio Esteban  Enric Massutí 《水产资源保护:海洋与淡水生态系统》2019,29(3):461-471

Identification of Polyphenols from Chilean Brown Seaweeds Extracts by LC-DAD-ESI-MS/MS     

Carla Olate-Gallegos  Andrés Barriga  Cristina Vergara  Carolina Fredes  Paula García  Begoña Giménez 《Journal Of Aquatic Food Product Technology》2019,28(4):375-391

Polyphenol profiles were characterized in extracts of three Chilean brown seaweeds, Durvillaea antarctica (Chamisso) Hariot, Lessonia spicata (Suhr) Santelices, and Macrocystis integrifolia (Bory) by liquid chromatography with mass spectrometry detection (LC-MS/MS). Phlorotannins with different degrees of polymerization were identified in D. antarctica (trimers to octamers) and L. spicata (trimers to tetramers). No signals related to phlorotannins compounds were detected in M. integrifolia. L. spicata and M. integrifolia showed a great variety of flavonoid compounds in comparison with D. antarctica, mainly identified as glycoside forms in all the extracts. The antioxidant activity of brown seaweed extracts measured by ferric reducing power (FRAP) and oxygen radical absorbance capacity (ORAC) was significantly higher in D. antarctica, followed by M. integrifolia and L. spicata, in line with the total phenolic (TP) content. However, D. antarctica and M. integrifolia showed similar activity for free radical 2,2-diphenyl-1-picrylhydrazyl (DPPH) in spite of the differences found in TP content. D. antarctica as well as L. spicata would represent a potential source of phlorotannins, whereas M. integrifolia could be considered as an alternative source of flavonoids. The identification of polyphenols in extracts of Chilean brown seaweeds opens innovative opportunities for their use in the food and pharmaceutical industries.  相似文献   

Effect of environmental factors on the fatty acid profiles and physicochemical composition of oysters (Crassostrea gasar) in Amazon estuarine farming     

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   

Presence of Grapevine leafroll-associated virus 3 in primary salivary glands of the mealybug vector Planococcus citri suggests a circulative transmission mechanism     

Miguel Cid  Sonia Pereira  Cristina Cabaleiro  Franco Faoro  Antonio Segura 《European journal of plant pathology / European Foundation for Plant Pathology》2007,118(1):23-30

Grapevine leafroll-associated virus 3 (GLRaV-3) is a mealybug-transmissible ampelovirus. Though the transmission mechanism has been described as semipersistent on the basis of temporal parameters, definitive proof of this mechanism has never been provided. In the present study, we carried out preliminary assays to establish the location of the virus in its vector, Planococcus citri. After dissecting the insects, GLRaV-3 was detected by means of IC-RT-PCR in the salivary glands, intestine and Malpighian tubes, but not in the sucking apparatus. Immunogold labelling of the capsid protein revealed the presence of the virus in some cells of the primary salivary glands, but not in the alimentary channel of the stylet, or in the accessory salivary glands. The strong labelling of the electron-dense secretion vesicles in some cells of the primary salivary glands, together with the non-detection of the virus in the sucking apparatus suggests that the transmission mechanism may be different from that previously described. We propose a circulative transmission mechanism based on a specific transportation route for the viral particles from the midgut or hindgut to the salivary glands. As the transmission mechanism is generally a common feature of a viral genus, the existence of a circulative transmission mechanism for other mealybug-transmitted ampeloviruses is expected. Organ by organ analysis of GLRaV-1, another ampelovirus not transmissible by P. citri, showed the absence of the virus in the salivary glands, thus providing further, though indirect, evidence in favour of circulative transmission for this virus genus.  相似文献