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1.
Belletti N Ndagijimana M Sisto C Guerzoni ME Lanciotti R Gardini F 《Journal of agricultural and food chemistry》2004,52(23):6932-6938
The aim of this research was to assess the antimicrobial activity of nine different industrial essences used in a soft drink factory in relation to their composition, as well as to verify the role of vapor pressure on their bioactivity. The essences were tested against a Saccharomyces cerevisiae strain isolated from spoiled soft drinks. The tests were carried out by adding the essences directly to a liquid medium or into the headspace of closed systems inoculated with the yeast. The headspace composition was evaluated through a solid phase microextraction-gas chromatography technique. The use of a mass spectrometer allowed the identification of the peaks detected. The microbial growth was indirectly monitored by measuring the metabolic CO2 released by the yeast. The results obtained indicated that the most effective essences were characterized by the highest concentration of some terpenes, such as citral, beta-pinene, and p-cymene. Moreover, all of the essences were more bioactive when added directly to the liquid medium. 相似文献
2.
Lanciotti R Belletti N Patrignani F Gianotti A Gardini F Guerzoni ME 《Journal of agricultural and food chemistry》2003,51(10):2958-2963
The aims of this work were to evaluate the effects of different concentrations of hexanal, (E)-2-hexenal, hexyl acetate, and their mixtures on the fate of pathogenic species such as Escherichia coli, Salmonella enteritidis, and Listeria monocytogenes inoculated in model systems as well as the antimicrobial activity against the target species of the chosen molecules when added to the packaging atmosphere of inoculated fresh-sliced apples. The result obtained in this work pointed out the potential use of compounds such as hexanal, (E)-2-hexenal, and hexyl acetate for both the extension of shelf life and an improvement of hygienic safety of "minimally processed foods". In fact, hexanal, (E)-2-hexenal, and hexyl acetate had a significant inhibitory effect against pathogen microorganisms frequently isolated from raw materials (E. coli, S. enteritidis, and L. monocytogenes) when inoculated in both model and real systems. In this last condition, these compounds, at the levels used (150, 150, and 20 ppm for hexanal, hexyl acetate, and (E)-2-hexenal, respectively), displayed a bactericide effect on L. monocytogenes and they exhibited significant extensions of lag phase of E. coli and S. enteritidis inoculated at levels of 10(4)-10(5) CFU/g. 相似文献
3.
Rosalba Troncoso-Rojas Yolanda Corral-Acosta Alberto Sánchez-Estrada Raymundo García-Estrada Alfonso Aguilar-Valenzuela Javier Ojeda-Contreras Martín Ernesto Tiznado-Hernández 《Phytoparasitica》2009,37(5):445-451
The fungicidal activity of allyl-isothiocyanate (allyl-ITC), benzyl-isothiocyanate (benzyl-ITC) and a mixture of isothiocyanates
(allyl-ITC, benzyl-ITC, phenyl-isothiocyanate and 2-phenylethyl-isothiocyanate; MCIT), was tested in netted melon infected
with Alternaria alternata as, was the effect of these compounds on the postharvest quality. Fruits were inoculated with A. alternata and exposed to allyl-ITC, benzyl-ITC, or MCIT, at 0.25 and 0.5 mg ml−1 concentrations. A commercial fungicide, Captan (CF), was used as a positive control. The fruit was stored at 20°C and 92%
relative humidity for up to 8 days. Allyl-ITC and MCIT at both tested concentrations, significantly reduced Alternaria rot,
by 82.73% to 88.67%. None of the ITC treatments had a significant effect on weight loss, total soluble solids, titratable
acidity or pH. Fruits treated with 0.5 mg ml−1 of AITC were more firm than others. Treatment with allyl-ITC, benzyl-ITC, or MCIT appears to be a promising alternative to
synthetic fungicides for controlling postharvest diseases in netted melon. 相似文献
4.
Martelli G Boccuzzi R Grandi M Mazzone G Zaghini G Sardi L 《Berliner und Münchener tier?rztliche Wochenschrift》2010,123(11-12):457-462
Eighty Italian heavy pigs having an initial body weight of about 75 kg were allotted to two experimental groups: a low light intensity group (LL), in which pigs received the lowest level of illumination mandatory in piggeries (40 lux) and a high light intensity group (HL), in which pigs were exposed to a higher level of illumination (80 lux). For both groups the light phase lasted 12 hours per day. Pigs were slaughtered at about 160 kg body weight. Light intensity showed to have no effects on the growth traits, carcass parameters or neutrophil-to-lymphocyte ratio of heavy. With the exception of drinking (more frequently observed among LL pigs; P < 0.01) and sternal recumbency (more frequently observed among pigs belonging to HL group; P < 0.01), the behavioural observations, carried out on 20 pigs per group, indicated that light intensity did not affect the main behavioural traits of pigs. Agonistic interactions were significantly higher (P < 0.05) among pigs receiving a lower level of illumination (40 lux; LL group) and pigs exposed to the higher level of illumination (80 lux; HL group) showed a tendency (P < 0.1) towards a higher proportion of tactile social interactions. Our results confirm that a proper illumination level can be included among environmental conditions having a positive effect in order to preserve swine welfare. 相似文献
5.
Numerous time series studies have quantified the potential association between daily variations in air pollution and daily variations in non-accidental deaths. In order to account for the presence of unmeasured confounders, a smooth function of time trend is typically used as a proxy for these variables. We shed light on the validity of the results obtained by using this approach. Specifically, we use data from the National Morbidity, Mortality and Air Pollution Study database, and carry out a carefully designed simulation study. Our findings suggest that the use of a smooth function of time trend cannot fully account for the presence of unmeasured confounders, especially when their impact is strong relatively to the effect of air pollution, and when several unobservables are not included in the model. 相似文献
6.
S Naik N Bouladoux C Wilhelm MJ Molloy R Salcedo W Kastenmuller C Deming M Quinones L Koo S Conlan S Spencer JA Hall A Dzutsev H Kong DJ Campbell G Trinchieri JA Segre Y Belkaid 《Science (New York, N.Y.)》2012,337(6098):1115-1119
Intestinal commensal bacteria induce protective and regulatory responses that maintain host-microbial mutualism. However, the contribution of tissue-resident commensals to immunity and inflammation at other barrier sites has not been addressed. We found that in mice, the skin microbiota have an autonomous role in controlling the local inflammatory milieu and tuning resident T lymphocyte function. Protective immunity to a cutaneous pathogen was found to be critically dependent on the skin microbiota but not the gut microbiota. Furthermore, skin commensals tuned the function of local T cells in a manner dependent on signaling downstream of the interleukin-1 receptor. These findings underscore the importance of the microbiota as a distinctive feature of tissue compartmentalization, and provide insight into mechanisms of immune system regulation by resident commensal niches in health and disease. 相似文献
7.
R. Gornati S. Gualdoni R. Cavaliere G. Terova M. Saroglia G. Bernardini 《Aquaculture International》2005,13(1-2):51-55
The issue of animal welfare in aquaculture is of growing interest and there is an increasing consumer demand for documentation of safe and ethically defendable food production. In this context, we have looked for molecular markers among those genes whose expression is modified by the different farming conditions. We have compared gene expression of sea bass farmed at different population densities by differential display, and we have obtained six bands differentially expressed whose sequences have been deposited in the public databases; two of them were suppressed by high population density, while four were induced by the treatment. These genes can be used as biomarkers, and together with a panel of stress-related genes of sea bass (D. labrax) that we have already obtained, could allow the rapid diagnosis of the welfare status of a fish using RT-PCR. We are certain that the new molecular techniques will find their place in the everyday management of fish farming. On the other hand, we are also aware that the scarcity of genomic resources for some fish species, in spite of their economical interest, will retard the beneficial effects that modern biotechnology could bring to aquaculture industry. Therefore, an effort should be made to reduce, as far genomic resources are concerned, the gap that separates farmed species from model organisms such as Danio rerio and Fugu rubripes. 相似文献
8.
9.
AY Escobedo-Lozano N Estrada F Ascencio G Contreras R Alonso-Rodriguez 《Marine drugs》2012,10(5):1044-1065
The dinoflagellate Gymnodinium catenatum produces paralyzing shellfish poisons that are consumed and accumulated by bivalves. We performed short-term feeding experiments to examine ingestion, accumulation, biotransformation, histopathology, and paralysis in the juvenile Pacific calico scallop Argopecten ventricosus that consume this dinoflagellate. Depletion of algal cells was measured in closed systems. Histopathological preparations were microscopically analyzed. Paralysis was observed and the time of recovery recorded. Accumulation and possible biotransformation of toxins were measured by HPLC analysis. Feeding activity in treated scallops showed that scallops produced pseudofeces, ingestion rates decreased at 8 h; approximately 60% of the scallops were paralyzed and melanin production and hemocyte aggregation were observed in several tissues at 15 h. HPLC analysis showed that the only toxins present in the dinoflagellates and scallops were the N-sulfo-carbamoyl toxins (C1, C2); after hydrolysis, the carbamate toxins (epimers GTX2/3) were present. C1 and C2 toxins were most common in the mantle, followed by the digestive gland and stomach-complex, adductor muscle, kidney and rectum group, and finally, gills. Toxin profiles in scallop tissue were similar to the dinoflagellate; biotransformations were not present in the scallops in this short-term feeding experiment. 相似文献
10.
Rosalba Gornati Genziana Terova Davide Vigetti Mariangela Prati Marco Saroglia Giovanni Bernardini 《Aquaculture (Amsterdam, Netherlands)》2004,230(1-4):229-239
The issue of animal welfare in aquaculture is growing of interest and there is an increasing consumer demand for documentation of safe and ethically defendable food production. In this context, we have looked for molecular markers among those genes whose expression results modified by the different farming conditions. We have compared gene expression of seabass farmed at different population densities by differential display. We have obtained six bands differentially expressed whose sequences we have deposited in the public databases; two of them resulted suppressed by high population density, while four were induced by the treatment. Population density has, therefore, an effect at gene level by repressing or enhancing the expression of different genes. These genes can be used as biomarkers to rapidly detect, by polymerase chain reaction (PCR), the occurred exposure of the fish to the stressor.
We are certain that the new molecular techniques will find their place in the everyday management of fish farming; on the other hand, we are also aware that the scarcity of the genomic resources for some fish species, in spite of their economical interest, will retard the beneficial effects that modern biotechnology could bring to aquaculture industry. Therefore, an effort should be made to reduce, as far as it concerns genomics resources, the gap that separates farming species from “model organisms”. 相似文献