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1.
Parasitol Res ; 123(5): 204, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38709330

RESUMO

In recent years, there has been growing concern on the potential weakening of honey bees and their increased susceptibility to pathogens due to chronic exposure to xenobiotics. The present work aimed to study the effects on bees undergoing an infection by Nosema ceranae and being exposed to a frequently used in-hive acaricide, amitraz. To achieve this, newly emerged bees were individually infected with N. ceranae spores and/or received a sublethal concentration of amitraz in their diets under laboratory conditions. Mortality, food intake, total volume excrement, body appearance, and parasite development were registered. Bees exposed to both stressors jointly had higher mortality rates compared to bees exposed separately, with no difference in the parasite development. An increase in sugar syrup consumption was observed for all treated bees while infected bees fed with amitraz also showed a diminishment in pollen intake. These results coupled with an increase in the total number of excretion events, alterations in behavior and body surface on individuals that received amitraz could evidence the detrimental action of this molecule. To corroborate these findings under semi-field conditions, worker bees were artificially infected, marked, and released into colonies. Then, they were exposed to a commercial amitraz-based product by contact. The recovered bees showed no differences in the parasite development due to amitraz exposure. This study provides evidence to which extent a honey bee infected with N. ceranae could potentially be weakened by chronic exposure to amitraz treatment.


Assuntos
Nosema , Toluidinas , Animais , Abelhas/efeitos dos fármacos , Abelhas/microbiologia , Abelhas/parasitologia , Nosema/efeitos dos fármacos , Nosema/fisiologia , Acaricidas
2.
Environ Microbiome ; 18(1): 38, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37098635

RESUMO

Pollinators, including solitary bees, are drastically declining worldwide. Among the factors contributing to this decline, bee pathogens and different land uses are of relevance. The link between the gut microbiome composition and host health has been recently studied for social pollinators (e.g. honeybees), whereas the information related to solitary bees is sparse. This work aimed at the characterization of the gut microbiome of the solitary bees Xylocopa augusti, Eucera fervens and Lasioglossum and attempted to correlate the gut microbial composition with the presence and load of different pathogens and land uses. Solitary bees were sampled in different sites (i.e. a farm, a natural reserve, and an urban plant nursery) showing different land uses. DNA was extracted from the gut, 16S rRNA gene amplified and sequenced. Eight pathogens, known for spillover from managed bees to wild ones, were quantified with qPCR. The results showed that the core microbiome profile of the three solitary bees significantly varied in the different species. Pseudomonas was found as the major core taxa in all solitary bees analyzed, whereas Lactobacillus, Spiroplasma and Sodalis were the second most abundant taxa in X. augusti, E. fervens and Lasioglossum, respectively. The main pathogens detected with qPCR were Nosema ceranae, Nosema bombi and Crithidia bombi, although differently abundant in the different bee species and sampling sites. Most microbial taxa did not show any correlation with the land use, apart from Snodgrassella and Nocardioides, showing higher abundances on less anthropized sites. Conversely, the pathogens species and load strongly affected the gut microbial composition, with Bifidobacterium, Apibacter, Serratia, Snodgrassella and Sodalis abundance that positively or negatively correlated with the detected pathogens load. Therefore, pathogens presence and load appear to be the main factor shaping the gut microbiome of solitary bees in Argentina.

3.
Plants (Basel) ; 11(23)2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36501370

RESUMO

Varroa destructor is a parasitic mite, which is considered a severe pest for honey bees causing serious losses to beekeeping. Residual hydrolats from steam extraction of hop essential oils, generally considered as a waste product, were tested for their potential use as acaricides on V. destructor. Four hop varieties, namely Cascade, Spalt, Victoria, and Mapuche, showed an interesting performance as feasible products to be used in the beekeeping industry. Some volatile oxidized terpenoids were found in the hydrolats, mainly ß-caryophyllene oxide, ß-linalool, and isogeraniol. These compounds, together with the presence of polyphenols, flavonoids, and saponins, were probably responsible for the promissory LC50 values obtained for mites after hydrolat exposition. Victoria hydrolat was the most toxic for mites (LC50: 16.1 µL/mL), followed by Mapuche (LC50 value equal to 30.1 µL/mL), Spalt (LC50 value equal to 114.3 µL/mL), and finally Cascade (LC50: 117.9 µL/mL). Likewise, Spalt had the highest larval survival, followed by Victoria and Mapuche. Cascade was the variety with the highest larval mortality. In addition, none of the extracts showed mortality higher than 20% in adult bees. The Victoria hydrolat presented the best results, which makes it a good compound with the prospect of an acaricide treatment against V. destructor.

4.
Genetica ; 149(5-6): 343-350, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34698977

RESUMO

Analysis of the mtDNA variation in Apis mellifera L. has allowed distinguishing subspecies and evolutionary lineages by means of different molecular methods; from RFLP, to PCR-RFLP and direct sequencing. Likewise, geometric morphometrics (GM) has been used to distinguish Africanized honey bees with a high degree of consistency with studies using molecular information. High-resolution fusion analysis (HRM) allows one to quickly identify sequence polymorphisms by comparing DNA melting curves in short amplicons generated by real-time PCR (qPCR). The objective of this work was to implement the HRM technique in the diagnosis of Africanization of colonies of A. mellifera from Argentina, using GM as a validation method. DNA was extracted from 60 A. mellifera colonies for mitotype identification. Samples were initially analyzed by HRM, through qPCRs of two regions (485 bp/385 bp) of the mitochondrial cytochrome b gene (cytb). This technique was then optimizing to amplify a smaller PCR product (207 bp) for the HRM diagnosis for the Africanization of colonies. Of the 60 colony samples analyzed, 41 were classified as colonies of European origin whereas 19 revealed African origin. All the samples classified by HRM were correctly validated by GM, demonstrating that this technique could be implemented for a rapid identification of African mitotypes in Apis mellifera samples.


Assuntos
Abelhas/classificação , Abelhas/genética , DNA Mitocondrial/genética , Filogenia , Animais , Citocromos b/genética , Evolução Molecular , Genes Mitocondriais/genética , Desnaturação de Ácido Nucleico , Reprodutibilidade dos Testes
5.
J Sci Food Agric ; 101(12): 5082-5088, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33570749

RESUMO

BACKGROUND: Kiwifruit is an important horticultural crop all over the world and its development is important in Argentina. This dioecious crop has a short blooming period with nectarless flowers, and its fruit production depends on cross-pollination. Here, we tested whether kiwifruit quality increases by using honeybees exposed to female flowers treated with an artificial fragrance. The three experimental treatments were: A, sprinkled female flowers with 1:1 sugar syrup + Lavandula hybrida extract solution (a new attractant substance especially developed for this study named Lavandin Grosso); B, sprinkled female flowers with 1:1 water + sugar syrup (female flowers with additional sugar syrup reward); C (control; female flowers exposed to honeybees). RESULTS: The results showed a higher number of visits of honeybees to the female flowers sprinkled with the attractant substance, Lavandin Grosso, as well as higher fruit quality (weight, number of seeds, regularity in fruit size). CONCLUSION: Our study demonstrates the potential of fragrance-treated flowers to improve yield production in kiwifruit. © 2021 Society of Chemical Industry.


Assuntos
Actinidia/parasitologia , Abelhas/fisiologia , Frutas/química , Odorantes/análise , Actinidia/química , Actinidia/crescimento & desenvolvimento , Animais , Argentina , Flores/crescimento & desenvolvimento , Flores/parasitologia , Frutas/crescimento & desenvolvimento , Frutas/parasitologia , Polinização , Controle de Qualidade
6.
Parasitol Int ; 81: 102244, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33217549

RESUMO

Lotmaria passim (Kinetoplastea) is considered the most prevalent as well as the most virulent trypanosomatid associated to the European honey bee Apis mellifera. We used qPCR to screen for the presence of this parasite in 57 samples from ten Argentinian provinces, and were able to detect its presence throughout most of the country with 41% of the samples testing positive. In a retrospective analysis, we detected L. passim in 73% of honey bee samples from 2006 showing that this flagellate has been widely present in Argentina for at least ~15 years. Additionally, three primer sets for L. passim detection were compared, with the pair that produced smallest PCR product having the best detection capability. Finally, we also found L. passim DNA in 100% (n = 6) of samples of the mite Varroa destructor. The role of this ectoparasite in the lifecycle of Lotmaria, if any, remains unrevealed.


Assuntos
Abelhas/parasitologia , Trypanosomatina/isolamento & purificação , Animais , Argentina
7.
Vet Sci ; 7(4)2020 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-33302502

RESUMO

Acaricides and the gut parasite Nosema ceranae are commonly present in most productive hives. Those stressors could be affecting key semiochemicals, which act as homeostasis regulators in Apis mellifera colonies, such as cuticular hydrocarbons (CHC) involved in social recognition and ethyl oleate (EO) which plays a role as primer pheromone in honey bees. Here we test the effect of amitraz, coumaphos, tau-fluvalinate and flumethrin, commonly applied to treat varroosis, on honey bee survival time, rate of food consumption, CHC profiles and EO production on N. ceranae-infected and non-infected honey bees. Different sublethal concentrations of amitraz, coumaphos, tau-fluvalinate and flumethrin were administered chronically in a syrup-based diet. After treatment, purified hole-body extracts were analyzed by gas chromatography coupled to mass spectrometry. While N. ceranae infection was also shown to decrease EO production affecting survival rates, acaricides showed no significant effect on this pheromone. As for the CHC, we found no changes in relation to the health status or consumption of acaricides. This absence of alteration in EO or CHC as response to acaricides ingestion or in combination with N. ceranae, suggests that worker honey bees exposed to those highly ubiquitous drugs are hardly differentiated by nest-mates. Having determined a synergic effect on mortality in worker bees exposed to coumaphos and Nosema infection but also, alterations in EO production as a response to N. ceranae infection it is an interesting clue to deeper understand the effects of parasite-host-pesticide interaction on colony functioning.

8.
PLoS One ; 15(11): e0241666, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33147299

RESUMO

When developing new products to be used in honeybee colonies, further than acute toxicity, it is imperative to perform an assessment of risks, including various sublethal effects. The long-term sublethal effects of xenobiotics on honeybees, more specifically of acaricides used in honeybee hives, have been scarcely studied, particularly so in the case of essential oils and their components. In this work, chronic effects of the ingestion of Eupatorium buniifolium (Asteraceae) essential oil were studied on nurse honeybees using laboratory assays. Survival, food consumption, and the effect on the composition of cuticular hydrocarbons (CHC) were assessed. CHC were chosen due to their key role as pheromones involved in honeybee social recognition. While food consumption and survival were not affected by the consumption of the essential oil, CHC amounts and profiles showed dose-dependent changes. All groups of CHC (linear and branched alkanes, alkenes and alkadienes) were altered when honeybees were fed with the highest essential oil dose tested (6000 ppm). The compounds that significantly varied include n-docosane, n-tricosane, n-tetracosane, n-triacontane, n-tritriacontane, 9-tricosene, 7-pentacosene, 9-pentacosene, 9-heptacosene, tritriacontene, pentacosadiene, hentriacontadiene, tritriacontadiene and all methyl alkanes. All of them but pentacosadiene were up-regulated. On the other hand, CHC profiles were similar in healthy and Nosema-infected honeybees when diets included the essential oil at 300 and 3000 ppm. Our results show that the ingestion of an essential oil can impact CHC and that the effect is dose-dependent. Changes in CHC could affect the signaling process mediated by these pheromonal compounds. To our knowledge this is the first report of changes in honeybee cuticular hydrocarbons as a result of essential oil ingestion.


Assuntos
Abelhas/efeitos dos fármacos , Abelhas/metabolismo , Eupatorium/química , Óleos Voláteis/metabolismo , Óleos Voláteis/toxicidade , Alcanos/metabolismo , Alcenos/metabolismo , Animais , Abelhas/microbiologia , Hidrocarbonetos/metabolismo , Nosema/patogenicidade
9.
Arch Virol ; 165(9): 2053-2056, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32556548

RESUMO

Chronic bee paralysis virus (CBPV) is a positive single-stranded RNA virus that exhibits a worldwide distribution. Although the effects of this virus on honeybees' health are well known, its presence in other bee species has not been fully studied. In this work, CBPV was detected in several native bees from Argentina, including Bombus pauloensis, Halictillus amplilobus, Peponapis fervens, and members of the genus Xylocopa. Here, we report for the first time the presence of CBPV in native bees from South America.


Assuntos
Abelhas/virologia , Vírus de Insetos/isolamento & purificação , Vírus de RNA/isolamento & purificação , Animais , Argentina , Abelhas/classificação , Vírus de Insetos/classificação , Vírus de Insetos/genética , Filogenia , Vírus de RNA/classificação , Vírus de RNA/genética
10.
Insects ; 10(11)2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31726686

RESUMO

The high annual losses of managed honey bees (Apis mellifera) has attracted intensive attention, and scientists have dedicated much effort trying to identify the stresses affecting bees. There are, however, no simple answers; rather, research suggests multifactorial effects. Several works have been reported highlighting the relationship between bees' immunosuppression and the effects of malnutrition, parasites, pathogens, agrochemical and beekeeping pesticides exposure, forage dearth and cold stress. Here we analyze a possible connection between immunity-related signaling pathways that could be involved in the response to the stress resulted from Varroa-virus association and cold stress during winter. The analysis was made understanding the honey bee as a superorganism, where individuals are integrated and interacting within the colony, going from social to individual immune responses. We propose the term "Precision Nutrition" as a way to think and study bees' nutrition in the search for key molecules which would be able to strengthen colonies' responses to any or all of those stresses combined.

11.
Insects ; 10(10)2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31581467

RESUMO

In temperate climates, beekeeping operations suffer colony losses and colony depopulation of Apis mellifera during overwintering, which are associated with biotic and abiotic stressors that impact bees' health. In this work, we evaluate the impacts of abscisic acid (ABA) dietary supplementation on honey bee colonies kept in Langstroth hives. The effects of ABA were evaluated in combination with two different beekeeping nutritional strategies to confront overwintering: "honey management" and "syrup management". Specifically, we evaluated strength parameters of honey bee colonies (adult bee and brood population) and the population dynamics of Nosema (prevalence and intensity) associated with both nutritional systems and ABA supplementation during the whole study (late autumn-winter-early spring). The entire experiment was designed and performed with a local group of beekeepers, "Azahares del sudeste", who showed interest in answering problems associated with the management of honey bee colonies during the winter. The results indicated that the ABA supplementation had positive effects on the population dynamics of the A. mellifera colonies during overwintering and on the nosemosis at colony level (prevalence) in both nutritional strategies evaluated.

12.
Insects ; 8(3)2017 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-28809782

RESUMO

Many biotic and abiotic stressors impact bees' health, acting as immunosupressors and contribute to colony losses. Thus, the importance of studying the immune response of honey bees is central to develop new strategies aiming to enhance bees' fitness to confront the threats affecting them. If a pathogen breaches the physical and chemical barriers, honey bees can protect themselves from infection with cellular and humoral immune responses which represent a second line of defense. Through a series of correlative studies we have previously reported that abscisic acid (ABA) and nitric oxide (NO) share roles in the same immune defenses of Apis mellifera (A. mellifera). Here we show results supporting that the supplementation of bee larvae's diet reared in vitro with l-Arginine (precursor of NO) or ABA enhanced the immune activation of the granulocytes in response to wounding and lipopolysaccharide (LPS) injection.

13.
Proc Biol Sci ; 284(1852)2017 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-28381619

RESUMO

The natural composition of nutrients present in food is a key factor determining the immune function and stress responses in the honeybee (Apis mellifera). We previously demonstrated that a supplement of abscisic acid (ABA), a natural component of nectar, pollen, and honey, increases honeybee colony survival overwinter. Here we further explored the role of ABA in in vitro-reared larvae exposed to low temperatures. Four-day-old larvae (L4) exposed to 25°C for 3 days showed lower survival rates and delayed development compared to individuals growing at a standard temperature (34°C). Cold-stressed larvae maintained higher levels of ABA for longer than do larvae reared at 34°C, suggesting a biological significance for ABA. Larvae fed with an ABA-supplemented diet completely prevent the low survival rate due to cold stress and accelerate adult emergence. ABA modulates the expression of genes involved in metabolic adjustments and stress responses: Hexamerin 70b, Insulin Receptor Substrate, Vitellogenin, and Heat Shock Proteins 70. AmLANCL2, the honeybee ABA receptor, is also regulated by cold stress and ABA. These results support a role for ABA increasing the tolerance of honeybee larvae to low temperatures through priming effects.


Assuntos
Ácido Abscísico/administração & dosagem , Abelhas/fisiologia , Temperatura Baixa , Animais , Larva/fisiologia
14.
Microb Ecol ; 74(4): 761-764, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28389730

RESUMO

Besides the incipient research effort, the role of parasites as drivers of the reduction affecting pollinator populations is mostly unknown. Given the worldwide extension of the beekeeping practice and the diversity of pathogens affecting Apis mellifera populations, honey bee colonies are a certain source of parasite dispersion to other species. Here, we communicate the detection of the microsporidium Nosema ceranae, a relatively new parasite of honey bees, in stingless bees (Meliponini) and the social wasp Polybia scutellaris (Vespidae) samples from Argentina and Brazil by means of duplex PCR. Beyond the geographic location of the nests, N. ceranae was detected in seven from the eight Meliponini species analyzed, while Nosema apis, another common parasite of A. mellifera, was absent in all samples tested. Further research is necessary to determine if the presence of the parasite is also associated with established infection in host tissues. The obtained information enriches the current knowledge about pathologies that can infect or, at least, be vectored by native wild pollinators from South America.


Assuntos
Abelhas/microbiologia , Nosema/fisiologia , Vespas/microbiologia , Animais , Argentina , Brasil , Nosema/genética , RNA Fúngico/análise , RNA Ribossômico 16S/análise
15.
Vet Res ; 47(1): 51, 2016 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-27118545

RESUMO

Nosema ceranae is an obligate intracellular parasite and the etiologic agent of Nosemosis that affects honeybees. Beside the stress caused by this pathogen, honeybee colonies are exposed to pesticides under beekeeper intervention, such as acaricides to control Varroa mites. These compounds can accumulate at high concentrations in apicultural matrices. In this work, the effects of parasitosis/acaricide on genes involved in honeybee immunity and survival were evaluated. Nurse bees were infected with N. ceranae and/or were chronically treated with sublethal doses of coumaphos or tau-fluvalinate, the two most abundant pesticides recorded in productive hives. Our results demonstrate the following: (1) honeybee survival was not affected by any of the treatments; (2) parasite development was not altered by acaricide treatments; (3) coumaphos exposure decreased lysozyme expression; (4) N. ceranae reduced levels of vitellogenin transcripts independently of the presence of acaricides. However, combined effects among stressors on imagoes were not recorded. Sublethal doses of acaricides and their interaction with other ubiquitous parasites in colonies, extending the experimental time, are of particular interest in further research work.


Assuntos
Acaricidas/farmacologia , Abelhas/efeitos dos fármacos , Microsporidiose/veterinária , Nosema , Animais , Abelhas/imunologia , Abelhas/microbiologia , Abelhas/parasitologia , Expressão Gênica/efeitos dos fármacos , Imunidade/efeitos dos fármacos , Imunidade/genética , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Varroidae/efeitos dos fármacos
16.
J Insect Physiol ; 59(1): 113-9, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23147024

RESUMO

The mite Varroa destructor is an ectoparasite affecting honey bees worldwide. Synthetic acaricides have been among the principal tools available to beekeepers for its control, although several studies have shown its negative effects on honey bee physiology. Recent research suggests that those molecules strongly impact on immune signaling cascades and cellular immunity. In the present work, LC(50) in six-day-old bees were determined for the following acaricides: tau-fluvalinate, flumethrin, amitraz and coumaphos. According to this obtained value, a group of individuals was treated with each acaricide and then processed for qPCR analysis. Transcript levels for genes encoding antimicrobial peptides and immune-related proteins were assessed. Flumethrin increased the expression of hymenoptaecin when comparing treated and control bees. Significant differences were recorded between coumaphos and flumethrin treatments, while the first one reduced the expression of hymenoptaecin and abaecin, the last one up-regulated their expressions. No significant statistically changes were recorded in the expression levels of vitellogenin, lysozyme or glucose dehydrogenase among bees treated with acaricides and control bees. This work constitutes the first report, under laboratory conditions, about induction of immune related genes in response to synthetic miticides.


Assuntos
Acaricidas/farmacologia , Abelhas/crescimento & desenvolvimento , Abelhas/genética , Expressão Gênica/efeitos dos fármacos , Proteínas de Insetos/genética , Acaricidas/síntese química , Animais , Abelhas/efeitos dos fármacos , Abelhas/imunologia , Proteínas de Insetos/imunologia
17.
Parasitol Res ; 110(6): 2333-40, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22190127

RESUMO

Phenotypic plasticity has been defined as the ability of a genotype to produce different phenotypes when exposed to distinct environments throughout its ontogeny. Morphological variability of individuals is an example of this plasticity. Taking into account that several studies have reported a wide morphological variability in Varroa destructor populations, we evaluated if the body size plasticity of the parasite constituted a key factor able to modulate mites survival when they were exposed to a drug bioassays. Drug bioassays against mites were conducted using three different Syzygium aromaticum essential oil concentrations (0.5, 1, and 5 µl/capsule) and controls. After 4 h of exposition, mite mortality was registered. The width (WS) and length (LS) of the dorsal shield were measured in dead mites. General lineal models were carried to determine if V. destructor survival to acaricides was related to the explanatory variables. Data modelling confirmed that WS and LS variables, together with time interaction, were significantly related to V. destructor survival when the parasites were exposed to acaricides. The models proposed demonstrated that for the smaller S. aromaticum essential oil concentration, the larger the parasite body, the greater the probability that it remains alive at the end of the bioassay. Such relationship was inverse for the other two concentrations tested. Possible causes explaining the body size variability in V. destructor individuals were discussed.


Assuntos
Acaricidas/farmacologia , Óleos Voláteis/farmacologia , Syzygium/química , Varroidae/anatomia & histologia , Varroidae/efeitos dos fármacos , Animais , Bioensaio , Tamanho Corporal , Modelos Estatísticos , Análise de Sobrevida
18.
Parasitol Res ; 110(2): 859-64, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21808980

RESUMO

Using molecular techniques, we documented the presence of Nosema ceranae in honeybees (Apis mellífera) from Argentina. Samples were collected from A. mellifera colonies in 38 districts of Buenos Aires province, Argentina. Molecular characterization was achieved with a multiplex PCR-based method, which allows parallel diagnosis of N. ceranae and N. osema apis. N. ceranae was identified in all the samples analyzed. Moreover, coinfections with N. apis were detected in Balcarce and Maipú districts. We identified three rRNA sequence variants of N. ceranae, which may represent diverse sources of bee importation. The results suggest that N. ceranae is widely distributed in Argentina and that the genetic variation observed between the different isolates could be related with the difference in the symptomatology found previously by our work group. Our results highlight the need to re-assess the health protocols currently in force so that they recognize N. ceranae as the main causal agent of Nosemosis in this country.


Assuntos
Abelhas/microbiologia , Variação Genética , Nosema/classificação , Nosema/isolamento & purificação , Animais , Argentina , Análise por Conglomerados , Coinfecção , DNA Fúngico/química , DNA Fúngico/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Genes de RNAr , Dados de Sequência Molecular , Reação em Cadeia da Polimerase Multiplex , Nosema/genética , Filogenia , RNA Fúngico/genética , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
19.
Parasitol Res ; 110(3): 1103-12, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21845411

RESUMO

The aim of the present work was to determine the in vitro effect of Mentha piperita and Mentha pulegium essential oils against Echinococcus granulosus and to compare the effectiveness of both oils according to the exposure time and concentration. Although both treatments had a protoscolicidal effect, M. pulegium had a considerably stronger effect than M. piperita. Essential oil of M. pulegium produced dose- and time-dependent effects. Maximal protoscolicidal effect was observed after 12 days of incubation and reached 0% after 18 days. This lack of viability was proved during the determination of infectivity into mice. Essential oil of M. piperita produced only a time-dependent effect. At 24 days p.i., the viability of protoscoleces decreased to approximately 50%. Scanning and transmission electron microscopy (SEM and TEM) demonstrated the drug-induced ultrastructural damage. On the other hand, a loss of turgidity was detected in all M. pulegium-treated cysts respective of the drug concentration. There was a correlation between the intensity of damage and the concentration of the essential oil assayed. Studies by SEM revealed that the germinal layer of treated cysts lost the feature multicellular structure. M. pulegium essential oil showed piperitone oxide as main compound in their composition, and we suggest that this component could be responsible of the markedly anthelmintic effect detected. Our data suggest that essential oils of Mentha spp. can be a promising source of potential protoscolicidal agents. The isolation of active anthelmintic constituents is in progress and may lead to the discovery of compounds with improved therapeutic value.


Assuntos
Anti-Helmínticos/farmacologia , Echinococcus granulosus/efeitos dos fármacos , Echinococcus granulosus/crescimento & desenvolvimento , Mentha piperita/química , Mentha pulegium/química , Óleos Voláteis/farmacologia , Animais , Anti-Helmínticos/química , Relação Dose-Resposta a Droga , Equinococose/tratamento farmacológico , Equinococose/parasitologia , Echinococcus granulosus/patogenicidade , Echinococcus granulosus/ultraestrutura , Feminino , Camundongos , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Óleos Voláteis/química , Testes de Sensibilidade Parasitária , Fitoterapia , Óleos de Plantas/química , Óleos de Plantas/farmacologia , Especificidade da Espécie , Análise de Sobrevida , Fatores de Tempo
20.
Parasitol Res ; 108(1): 79-86, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20838808

RESUMO

Extracts of indigenous plants from South America have shown a broad spectrum of bioactivities. No-contaminant and natural substances have recently resurged as control treatment options for varroosis in honey bee colonies from Argentina. The aim of this work was to evaluate the biological activity of botanical extracts from Baccharis flabellata and Minthostachys verticillata on Varroa destructor and Apis mellifera. The acaricidal and insecticidal activities were assessed by the spraying application method. Both ethanolic extracts showed high levels of toxicity against the mites and were harmless to their host, A. mellifera. During the attractive-repellent test, the olfactory stimulus evoked for the extract from B. flabellata resulted as a repellent for mites. The aromatic stimulus of these extracts would be strong enough to cause disturbance on the behavior of V. destructor. Thus, the repellent effect of these substances plus the toxicity on mites postulate these botanical extracts like promising natural compound to be incorporated for the control of varroosis.


Assuntos
Acaricidas/farmacologia , Baccharis/química , Repelentes de Insetos/farmacologia , Lamiaceae/química , Extratos Vegetais/farmacologia , Varroidae/efeitos dos fármacos , Acaricidas/isolamento & purificação , Acaricidas/toxicidade , Animais , Argentina , Abelhas/efeitos dos fármacos , Feminino , Repelentes de Insetos/isolamento & purificação , Repelentes de Insetos/toxicidade , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/toxicidade , Análise de Sobrevida
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