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2.
Insects ; 15(1)2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38249066

RESUMEN

Certain soil insects, such as the root-damaging larvae of the maize pest Diabrotica virgifera virgifera (Coleoptera: Chrysomelidae), are increasingly difficult to control because of recent bans of some insecticides. An alternative and safer approach may be the development of biopesticides based on entomotoxic defense proteins of higher fungi. Many of these potentially interesting proteins are protease inhibitors, and some have been shown to adversely affect insects. We examined the effects of the cysteine protease inhibitors macrocypin 1, 3, and 4 from Macrolepiota procera, clitocypin from Clitocybe nebularis, and cocaprin 1 and the serine protease inhibitor cospin 1 from Coprinopsis cinerea on D. v. virgifera. We confirmed the inhibition by mycocypins of the cysteine catalytic-type proteolytic activities in gut extracts of larvae and adults. The inhibition of pGlu-Phe-Leu-hydrolyzing activity was stronger than that of Z-Phe-Arg-hydrolyzing activity. Mycocypins and cospin resisted long-term proteolytic digestion, whereas cocaprin 1 was digested. Bioassays with overlaid artificial diet revealed no effects of proteins on neonatal mortality or stunting, and no effects on adult mortality. Immersion of eggs in protein solutions had little effect on egg hatching or mortality of hatching neonates. Microscopic analysis of the peritrophic matrix and apical surface of the midguts revealed the similarity between larvae of D. v. virgifera and the chrysomelid Leptinotarsa decemlineata, which are sensitive to these inhibitors. The resistance of D. v. virgifera to fungal protease inhibitors is likely due to effective adaptation of digestive enzyme expression to dietary protease inhibitors. We continue to study unique protein complexes of higher fungi for the development of new approaches to pest control.

3.
J Pharm Biomed Anal ; 235: 115611, 2023 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-37542828

RESUMEN

Enrichment of pharmaceutically important vinca alkaloids, vinblastine and vincristine, in the leaves of Madagascar periwinkle (Catharanthus roseus) plants through different pre- or postharvest treatments or cultivation conditions, e.g., exposing the plants to UV-irradiation, has been in focus for decades. Controlled LED environment in the visible light range offers the possibility of monitoring the changes in the concentration of metabolites in the vinca alkaloid-related pathway without involving UV-related abiotic stress. In the frame of our targeted metabolomics approach, 64 vinca alkaloids and metabolites were screened with the help of a UPLC-ESI-QTOF-MS instrumental setup from the leaf extracts of C. roseus plants grown in chambers under control (medium light), low light, and high blue / high red/ high far-red conditions. Out of the 14 metabolites that could be assigned either unambiguously with authentic standards or tentatively with high resolution mass spectrometry-based methods, all three dimer vinca alkaloids, that is, 3',4'-anhydrovinblastine, vinblastine and vincristine showed an at least nine-fold enrichment under high blue irradiation when compared with the control conditions: final concentrations of 961 mg kg-1 dry weight, 33.8 mg kg-1 dry weight, and 11.7 mg kg-1 dry weight could be achieved, respectively. As supported by multivariate statistical analysis, the key metabolites of the vinca alkaloid pathway were highly represented among the metabolites that were specifically stimulated by high blue light application.


Asunto(s)
Antineoplásicos , Catharanthus , Alcaloides de la Vinca , Alcaloides de la Vinca/análisis , Alcaloides de la Vinca/metabolismo , Vinblastina/metabolismo , Catharanthus/metabolismo , Vincristina , Antineoplásicos/metabolismo , Metabolómica
4.
Bioengineering (Basel) ; 10(6)2023 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-37370587

RESUMEN

Microencapsulation of extra virgin olive oil has been taken into consideration. Initially, emulsions were prepared using extra virgin olive oil and aqueous solutions of different proportions of maltodextrin (MD) having dextrose equivalent (DE) 19 and whey protein isolates (WPI), such as 100% MD, 100% WPI, 25% MD + 75% WPI, 50% MD + 50% WPI and 75% MD + 25% WPI. Subsequently, emulsions were used for dehydration by either spray-drying (SD) or freeze-drying (FD) to produce olive oil microcapsules. Emulsion stability, viscosity and droplet size influenced the characteristics of the microcapsules. The highest encapsulation efficiency was achieved using 50% MD + 50% WPI in the emulsions with subsequent SD. The moisture content of the microcapsules increased with increasing proportions of MD. The size of the microcapsules increased with increasing proportions of WPI. The bulk density and tapped density were reduced with higher proportions of MD in the microcapsules. Furthermore, microcapsules with a higher proportion of MD exhibited poor flowability and high cohesiveness. Microcapsules from the higher proportion MD emulsions, followed by SD were spherical with a smooth surface; however, microcapsules with dent structures were produced from 100% WPI in the emulsions with subsequent SD. Microcapsules, produced from emulsions with a higher proportion of WPI, followed by FD were flat flakes and had irregular surfaces.

5.
Membranes (Basel) ; 13(3)2023 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-36984716

RESUMEN

The goals of the present investigation are to study and to model pale lager beer dealcoholization via reverse osmosis (RO). Samples were dealcoholized at a temperature of 15 ± 1 °C. An Alfa Laval RO99 membrane with a 0.05 m2 surface was used. The flux values were measured during the separations. The ethanol content, extract content, bitterness, color, pH, turbidity, and dynamic viscosity of beer and permeate samples were measured. The initial flux values were determined using linear regression. The initial ethanol flux (JEtOH 0) values were calculated from the initial flux values and the ethanol content values. A 2P full factorial experimental design was applied, and the factors were as follows: transmembrane pressure (TMP): 10, 20, 30 bar; retentate flow rate (Q): 120, 180, 240 L/h; JEtOH 0 was considered as the response. The effect sizes of the significant parameters were calculated. The global maximum of the objective function was found using a self-developed Grid Search code. The changes in the analytical parameters were appropriate. The TMP had a significant effect, while the Q had no significant effect on the JEtOH 0. The effect size of the TMP was 1.20. The optimal value of the factor amounted to TMP = 30 bar. The predicted JEtOH 0 under the above conditions was 121.965 g/m2 h.

6.
Metallomics ; 15(1)2023 01 10.
Artículo en Inglés | MEDLINE | ID: mdl-36496173

RESUMEN

Automated and specific picking of selenium-containing molecular entities has not been an obvious option for software tools associated with electrospray high-resolution mass spectrometry (MS). In our study, a comprehensive pattern matching approach based on intra-isotopologue distance and isotopologue ratio data was critically evaluated in terms of reproducibility and selenium isotope selection on three samples, including selenized Torula yeast and the selenium hyperaccumulator plant Cardamine violifolia. Hydrophilic interaction liquid chromatography was applied to provide a one-step separation for water soluble metabolites to put an end to the need for either orthogonal setups or poor retention on reversed phase chromatography. Assistance from inductively coupled plasma-MS was taken only for chromatographic verification purposes, and the involvement of absolute mass defect (MD) data in selenometabolite-specific screening was assessed by multivariate statistical tools. High focus was placed on screening efficiency and on the validation of discovered selenized molecules to avoid reporting of artefacts. From the >1000 molecular entries detected, selenium-containing molecules were picked up with a recovery rate of >88% and a false positive rate of <10%. Isotop(ologu)e pairs of 78Se-80Se and 80Se-82Se proved to be the most performant in the detection. On the basis of accurate mass information and hypothetical deamination processes, elemental composition could be proposed for 72 species out of the 75 selenium species encountered without taking into account selenocompound databases. Absolute MD data were used to significantly differentiate a potentially sample-specific subgroup of false positive molecular entities from non-selenized and selenized entities.


Asunto(s)
Selenio , Selenio/metabolismo , Reproducibilidad de los Resultados , Cromatografía Líquida de Alta Presión/métodos , Espectrometría de Masa por Ionización de Electrospray/métodos , Cromatografía Liquida , Saccharomyces cerevisiae/metabolismo
7.
Arthropod Struct Dev ; 72: 101228, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36427428

RESUMEN

The onion thrips, Thrips tabaci Lindeman, is a cryptic species complex of three distinct lineages: L1, L2, and T, which exhibit considerable variation in their biological and ecological traits. The most accurate method for their identification is based on molecular techniques. This study aimed to investigate the morphometric variation of T. tabaci cryptic species complex and to distinguish characters that may be useful in discriminating the lineages. For this purpose, morphometric measurements were performed on the eggs, newly hatched first instar larvae, and newly emerged adults. Our results revealed significant differences in egg size between the three lineages. Moreover, the PCA analysis conducted on morphometric measurements of the first instar larvae and adults showed that females of the T lineage are very well separated from the females of the L lineages in the adult stage but not in the first instar larval stage. The distinction between the females is partially congruent with the results of genetic studies. Moreover, our results indicate that adult sexual dimorphism with regard to size in L1 and T lineages is not mediated by the size of eggs and first instar larvae, and this may be due to the different growth rates of males and females.


Asunto(s)
Thysanoptera , Femenino , Masculino , Animales , Thysanoptera/genética , Larva , Cebollas
8.
Plants (Basel) ; 11(24)2022 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-36559539

RESUMEN

There are hundreds of morphologic and morphometric traits available to classify and identify grapevine (Vitis vinifera L.) genotypes, while statistical evaluation of those has certain limitations, especially when we have no information about the traits that are discriminative to a certain sample set. High numbers of investigated characters could cause redundancy, while reducing those numbers may result in data loss. Grapevine is one of the most important horticultural crops, with many cultivars in production. The characterization of the genotypes is of undeniably high importance. In this study, we analyzed a dataset of scientific and historical importance with 125 morphological traits of 97 grapevine cultivars described by Németh in 1966. However, the traits are not independent in a set of a large number of categorical traits with too few cultivars. Therefore, the number of traits was first reduced using a simple and effective algorithm to eliminate traits with redundant information content using the asymmetric measure of association Goodman and Kruskal's λ. We reduced the number of traits from 125 to 59 without any information loss. For the classification, we applied a random forest (RF) method. In this way, 93% of the cultivars were correctly classified using only four traits of the data set. To our knowledge, only a few studies applied a trait elimination algorithm similar to ours in ampelography that can be used for other biological data sets of similar structure. The classification results give a morphological explanation to several cultivars from the Carpathian Basin, a territory where all three Vitis vinifera L. geographical groups, occidentalis, orientalis and pontica, are represented. We found that the information-loss-avoiding data reduction method we applied in our study solved the redundancy-caused interdependencies and provided a suitable dataset for classifying grapevine genotypes. For example, this method may successfully be applied in digital image analysis-based traditional morphometric investigations in ampelography.

9.
Insects ; 13(5)2022 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-35621744

RESUMEN

In two haplodiploid species, sex allocation in young arrhenotokous females is mediated by egg size. We tested if sex allocation is mediated by egg size in two arrhenotokous lineages of the haplodiploid species complex of T. tabaci: L1 and T. We measured the size of eggs produced by very young mothers, 3-5-day-old mothers (just like in the case of Tetranychus urticae) and 7-10-day-old mothers (as in Pezothrips kellyanus). Moreover, we measured the size of eggs oviposited by mothers in their entire lifespan. We found that in T. tabaci, sex allocation is not mediated by egg size. Egg size and gender were independent of maternal age in the L1 lineage, whilst in the T lineage, the observed egg size difference between males and females was only present in the progeny of young females (7-10-day-old mothers). Furthermore, we found that male eggs produced by mated mothers were larger than those produced by virgin mothers in the L1 lineage, but in the T lineage, there were no differences in the size of male eggs produced by mated and virgin mothers. Our results indicate that these two subspecies have different resource allocation strategies in response to maternal mating status.

10.
Biology (Basel) ; 11(3)2022 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-35336770

RESUMEN

Thrips tabaci Lindeman is a serious pest of various cultivated plants, with three, distinct lineages within a cryptic species complex. Despite the well-known significance of this pest, many attributes of these lineages are not yet fully understood, including their reproductive behaviour. We performed no-choice-design cross-mating experiments under a controlled laboratory environment with virgin adult individuals from all three lineages. The behaviour of thrips was recorded with a camera mounted on a stereomicroscope, and the recordings were analysed in detail. We found that the so-called leek-associated lineages of this cryptic species complex are reproductively isolated from the tobacco-associated lineage; therefore, they represent different species. Divergence in the behaviour of conspecific and heterospecific pairs became evident only after contact. There were no marked differences between the lineages in their precopulatory and copulatory behaviour, except in the duration of the latter. We confirmed mating between thelytokous females and arrhenotokous males; however, we assume some form of loss of function in the sexual traits of asexual females. The post-mating behaviour of males indicated the presence and role of an anti-aphrodisiac pheromone. We also demonstrated differences between lineages regarding their activity and their propensity for exhibiting an escape response upon interaction with heterospecific thrips.

11.
Foods ; 11(4)2022 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-35205995

RESUMEN

The use of minimal thermal processing techniques such as sous vide technology to improve the quality of meat-based foods has gained a special focus in recent years. A proper combination of temperature and time parameters in sous vide processing plays an important role in the water-holding capacity, texture properties, and juiciness of the meat. The present study aimed to assess the impact of the one-step and two-step sous vide processing on different quality properties of chicken breast with special emphasis on the cooking loss, color, texture properties, protein solubility, and lipid oxidation. According to the results, chicken breast treated with a two-step temperature (50 and 60 °C) showed improved texture parameters (shear force, hardness, chewiness, and gumminess), lower cooking loss, acceptable redness values, and decreased lipid oxidation levels than the chicken breast treated with the one-step temperature of 60 °C. Moreover, the two-step sous vide technique revealed significantly higher total protein solubility of the chicken breast than the one-step sous vide. Based on pasteurization values, the two-step sous vide technique was equally safe as the one-step sous vide technique for vegetative cells' inactivation for the main pathogens of interest (C. perfringens and L. monocytogenes).

12.
Int J Biol Macromol ; 192: 461-470, 2021 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-34600952

RESUMEN

Probiotic L. acidophilus La-14 cells were co-encapsulated with Ganoderma lingzhi extract to prolong the viability of the cells under simulated gastrointestinal (SGI) condition and to protect the active ingredients of Reishi mushroom during the storage period. Combinations of distinctive reagents (sodium alginate, chitosan, maltose, Hydroxyethyl-cellulose (HEC), hydroxypropyl methylcellulose (HPMC), and calcium lactate) were tested. Optimal double layer Ca-alginate hydrogel beads were fabricated with significantly improved characteristics. The incorporation of maltose significantly decreases the release rate of mushrooms' phenolics, antioxidants, and ß-glucan during the storage time. Significant improvement in probiotic cells viability under SGI condition has been found and confirmed by confocal laser microscopy in maltose containing double layer coated calcium alginate beads variants. The encapsulation of newly formulated prebiotic Reishi extract and probiotic L. acidophilus is creating a new potential food application for such medicinal mushrooms and natural products with unpleasant taste upon oral consumption.


Asunto(s)
Agaricales/química , Alginatos/química , Productos Biológicos/química , Ganoderma/química , Lactobacillus acidophilus/química , Probióticos/química , Antioxidantes/química , Antioxidantes/farmacología , Productos Biológicos/aislamiento & purificación , Productos Biológicos/farmacología , Fraccionamiento Químico/métodos , Fenómenos Químicos , Composición de Medicamentos/métodos , Glucosa/química , Metilcelulosa/química , beta-Glucanos/química
13.
Foods ; 10(9)2021 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-34574127

RESUMEN

The effect of heat treatment on dried fruiting bodies of Reishi medicinal mushroom (Ganoderma lingzhi) is investigated. Control and samples treated for 20 min at temperatures of 70, 120, 150 and 180 °C were subjected for their free radical scavenging capacity, different glucans and total phenolic content determination. The growth rate of Escherichia coli and Lactobacillus casei supplemented with control and heat-treated samples is also investigated. The roasted mushroom samples at 150 °C and 180 °C showed the highest level of ß-glucan (37.82%) and free radical scavenging capacity on 2,2-diphenyl-1-picrylhidrazyl (DPPH•) and 2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS•+). The content of total phenolics (TPC) was also influenced by heat treatment and significantly higher TPC values were recorded in samples treated at 120 °C and 150 °C. The presence of reducing sugars was only detected after heat treatment at 150 °C (0.23%) and at 180 °C (0.57%). The heat treatments at 120, 150 and 180 °C, significantly attenuated the number of colony-forming units (CFU) of pathogenic E. coli, in a linear relationship with an elevated temperature. The supplementation of heat-treated Reishi mushroom at 120 °C resulted in the highest growth rate of probiotic L. casei. The obtained results in this study revealed the significant effect of short-term heat treatment by enhancing the antioxidant capacity, ß-glucan solubility and prebiotic property of the dried basidiocarp of Reishi mushroom.

14.
Int J Biol Macromol ; 183: 1136-1144, 2021 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-33932423

RESUMEN

The probiotics are extremely sensitive to various environmental factors, which imposes limitation on their health and functional effectiveness. Thus, development of delivery system for protection of viable cells while passing through different stages of the human digestion system is key factor in application of probiotic products. In our study, the effects of several polysaccharides such as alginate, κ-carrageenan, locust bean gum, gellan gum, xanthan gum and their combination with various prebiotic components (resistant starch, lactulose, lactosucrose) on encapsulation of probiotic Lactobacillus casei 01 strain were studied. Both regular and unregular beads with size distributions from 2 mm up to 5 mm were obtained. The encapsulation efficiencies varied from 64.4% up to 79%. Based on the texture's profiles, the capsules can be grouped into 5 clusters with squared Euclidean distance 3.5. Meanwhile, the starch-alginate and the lactosucrose LS55L - alginate beads were found to be the most stable and to have massive textural properties, whereas the gellan gum - xanthan gum and the chitosan coated alginate beads emerged as the softest. Encapsulation significantly improved the degree of gastric tolerance of probiotic cells even in the presence of pepsin. The INFOGEST in vitro digestion protocol was adapted to investigate the protection effects of different capsules. The highest survival (with loss rate of lower than 1 log CFU/g) was observed in the case of the cells encapsulated in starch-alginate beads. Moreover, the alginate microcapsules combined with lactosucrose LS55L also provided very promising shield for probiotics from the low pH of gastric conditions. Our findings suggest that incorporation of prebiotics into alginate-base encapsulation would be good idea in development of micro delivery systems that helps the survival of probiotics and their delivery to the target sites of action in human body.


Asunto(s)
Lacticaseibacillus casei/fisiología , Polisacáridos/química , Probióticos/química , Composición de Medicamentos , Estabilidad de Medicamentos , Humanos , Concentración de Iones de Hidrógeno , Lactulosa/química , Tamaño de la Partícula , Prebióticos , Almidón Resistente , Sacarina/química , Trisacáridos/química
15.
J Environ Sci Health B ; 56(2): 99-108, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33571042

RESUMEN

Several components of mushroom compost (wheat straw, chicken manure) can be contaminated with mycotoxins posing food health risks to mushroom consumers. To assess the relevance of such contaminations high-throughput analytical methods are needed. In this study, two sample preparation approaches, dilute & shoot (D&S) and modified citrate buffered Quick, Easy, Cheap, Effective, Rugged, Safe (QuEChERS) were compared in terms of extraction efficiency and matrix effect in case of 13 mycotoxins in complex matrices-wheat straw, the growing media and button mushrooms (Agaricus bisporus)-of mushroom cultivation using high-performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS). D&S method resulted in recoveries of LB medium, button mushroom and compost for ≥60% in case of all investigated mycotoxins except for DON-3G. However, using modified citrate buffered QuEChERS with 2% acidification of the extraction solvent showed the complete loss of strongly polar DON-3G and fumonisin B1 (FB1). The investigated matrices had suppressive effect on ionization in all target mycotoxins except for FB1. Regarding the use of isotopologues to compensate matrix effect, even U-[13C15]-DON and U-[13C24]-T-2 can also be used to quantify their related metabolites in the studied matrices, using internal standard method.


Asunto(s)
Agaricus/química , Cromatografía Líquida de Alta Presión/métodos , Micotoxinas/análisis , Espectrometría de Masas en Tándem/métodos , Cromatografía Líquida de Alta Presión/instrumentación , Espectrometría de Masas en Tándem/instrumentación
16.
PLoS One ; 14(7): e0219975, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31318965

RESUMEN

Soil moisture is one of the most important factors affecting soil biota. In arid and semi-arid ecosystems, soil mesofauna is adapted to temporary drought events, but, until now, we have had a limited understanding of the impacts of the different magnitudes and frequencies of drought predicted to occur according to future climate change scenarios. The present study focuses on how springtails and mites respond to simulated repeated drought events of different magnitudes in a field experiment in a Hungarian semi-arid sand steppe. Changes in soil arthropod activities were monitored with soil trapping over two years in a sandy soil. In the first year (2014), we applied an extreme drought pretreatment, and in the consecutive year, we applied less devastating treatments (severe drought, moderate drought, water addition) to these sites. In the first year, the extreme drought pretreatment tended to have a negative effect (either significantly or not significantly) on the capture of all Collembola groups, whereas all mite groups increased in activity density. However, in the consecutive year, between the extreme drought and control treatments, we only detected differences in soil microbial biomass. In the cases of severe drought, moderate drought and water addition, we did not find considerable changes across the microarthropods, except in the case of epedaphic Collembola. In the cases of the water addition and drought treatments, the duration and timing of the manipulation seemed to be more important for soil mesofauna than their severity (i.e., the level of soil moisture decrease). We suggest that in these extreme habitats, soil mesofauna are able to survive extreme conditions, and their populations recover rapidly, but they may not be able to cope with very long drought periods.


Asunto(s)
Artrópodos , Biodiversidad , Sequías , Ecosistema , Suelo/parasitología , Animales , Biomasa , Suelo/química
17.
Int J Biol Macromol ; 136: 847-858, 2019 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-31226374

RESUMEN

Roseroot (Rhodiola rosea L.) is a medicinal plant with adaptogenic properties and several pharmaceutically important metabolites. In this study, a full length cDNA encoding a UDPG gene of roseroot was identified, cloned and characterized. Its ORF (1425 bp) was transferred into E. coli, where the expression of the recombinant enzyme was confirmed. To monitor the enzyme activity, 3 precursors (tyramine, 4-hydroxyphenylpyruvate & tyrosol) of salidroside biosynthesis pathway were added to roseroot callus cultures and samples were harvested after 1, 6, 12, 24, 48 & 96 h. Along with the controls (without precursor feeding), each sample was subjected to HPLC and qRT-PCR for phytochemical and relative UDP-glycosyltransferase gene expression analysis, respectively. The HPLC analysis showed that the salidroside content significantly increased; reaching 0.5% of the callus dry weight (26-fold higher than the control) after 96 h when 2 mM tyrosol was given to the media. The expression of the UDP-glycosyltransferase increased significantly being the highest at 12 h after the feeding. The effect of tyramine and 4-hydroxyphenylpyruvate was not as pronounced as of tyrosol. Here, we introduce a R. rosea specific UDPG gene and its expression pattern after biotransformation of intermediate precursors in in vitro roseroot callus cultures.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Glicosiltransferasas/genética , Glicosiltransferasas/metabolismo , Rhodiola/enzimología , Rhodiola/genética , Uridina Difosfato/metabolismo , Biotransformación , Técnicas de Cultivo , Alcohol Feniletílico/análogos & derivados , Alcohol Feniletílico/metabolismo , Filogenia , Rhodiola/crecimiento & desarrollo
18.
Poult Sci ; 97(2): 634-642, 2018 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-29077912

RESUMEN

Several studies have examined the potential biological effects of electromagnetic fields (EMF) on birds; however, little attention has been paid to the extremely low frequency (ELF; 0-300 Hz; 0-50 µT) radiation found in an urbanized environment. For monitoring the effects of ELF EMF, we used a turkey (Meleagris gallopavo) model, because the nucleated erythrocytes of turkeys contain ß-adrenoceptors, and norepinephrine- (NE-) activated ß-adrenoceptors have an important role in physiological and behavioral processes. Our aims were the following: 1) to investigate the intracellular mechanisms; 2) to compare the intracellular mechanisms in the treated and control groups over time, considering inter-individual differences and intra-subject correlations; 3) and to study the reversible nature of the response. The turkeys in the treatment group were treated in vivo with ELF EMF (50 Hz; 10 µT) for 3 wk after a 1-wk-long adaptation period. The animals were not exposed to ELF EMF during the regeneration period (5 wk following the exposure). The NE-activated ß-adrenoceptor function was detected by measuring the amount of 3΄5΄-cyclic-adenosine-monophosphate (cAMP), and the biochemical enzyme parameters were defined. Repeated measurements of cAMP levels were analyzed using marginal models and a piecewise linear mixed model to compare treatment and control groups over time. According to our results, NE-activated ß-adrenoceptor function was decreased in the treated birds in a time-dependent manner, while there were no differences between toxicological parameters in the serum, compared to the normal ranges. The decreased NE-dependent ß-adrenoceptor function could be compensated by the homeostatic complex during the 5-wk regeneration period. Extended experimental periods and more sophisticated analysis methods may help prevent harmful environmental effects on birds; furthermore, these findings could affect public health and the economy.


Asunto(s)
Campos Electromagnéticos/efectos adversos , Norepinefrina/metabolismo , Receptores Adrenérgicos beta/metabolismo , Pavos/metabolismo , Animales , AMP Cíclico/metabolismo , Femenino , Receptores Adrenérgicos beta/genética
19.
Plant Physiol Biochem ; 119: 170-177, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28881276

RESUMEN

The aim of the present study was to investigate the impact of water deficiency on five Melissa officinalis genotypes. For three months water supply of 70% (control) and 40% (stress) of soil water capacity treatments have been adjusted in a pot experiment. Considering the morphological data, the different genetic potentials of cultivars were manifested only under optimum water regimes while under drought they merged into one homogeneous basic population representing the species. The biomass data decreased for all cultivars under drought stress, but the degree of loss was genotype specific. Genotype dependence of the change in essential oil accumulation was clearly proved by the data. Three of the cultivars ('Gold Leaf', 'Lorelei' and 'Quedlinburger Niederliegende') showed the same essential oil content both in control and stress treatments. Under drought stress the cultivar 'Lemona' produced only 35% of its essential oil content, however cv. 'Soroksár' reacted with 58% increase of essential oil accumulation to drought treatment. Considering the non-volatile bioactive compounds a unique response of the investigated accessions to drought stress was demonstrated. Cultivar 'Lorelei' showed an increased accumulation of total hydroxicinnamic acid derivatives content while cv. 'Gold Leaf' and 'Soroksár' clearly reacted with higher accumulation of total flavonoid fraction. In the case of cv. 'Quedlinburger Niederliegende' the remarkable decline in total flavonoid content is the most obvious stress reaction. The rosmarinic acid content of all genotypes showed lower accumulation level in consequence of lower water supply.


Asunto(s)
Flavonoides/biosíntesis , Melissa/metabolismo , Aceites Volátiles/metabolismo , Estrés Fisiológico , Deshidratación/metabolismo
20.
Food Res Int ; 99(Pt 1): 198-205, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28784476

RESUMEN

The application of the Poincaré method is discussed on the field of sensory panel performance monitoring. The Poincaré plot evaluates and visualizes the difference from the consensus for each panelist even for one product and for one attribute. Sensory tests were carried out on 5 commercially available brands of pear-lemon and josta flavoured bottled waters. Several sensory parameters were assessed and a complex dissimilarity index was calculated. Based on this index the attributes and panelists can be ranked highlighting the attribute which was the hardest to evaluate and the most consistent panel member. Our method has been compared to the other methods using the sum of ranking difference method and cross-validated by leave-one-out technique. Regarding both the ranking of the panelists and the ranking of the attributes significant differences were found between the Poincaré method and the traditional techniques since the sum of ranking difference was greater than the critical value of 39 and 79 at 5%, respectively. Only the Poincaré method was able to indicate sweet flavour as the easiest attribute to evaluate. Free R code is available to carry out the calculations and apply this method.


Asunto(s)
Agua Carbonatada/análisis , Aromatizantes/análisis , Odorantes , Percepción Olfatoria , Percepción del Gusto , Gusto , Comportamiento del Consumidor , Humanos , Juicio , Modelos Estadísticos , Reproducibilidad de los Resultados , Análisis y Desempeño de Tareas , Percepción Visual
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