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1.
J Sci Food Agric ; 100(3): 1204-1212, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31696521

RESUMO

BACKGROUND: The aim of this study was to select appropriate low-toxicity degreasing solvents to degrease black soldier fly (BSF, Hermetia illucens L.) larvae to prepare high-quality protein. Aqueous ethyl acetate was chosen as the solvent to extract BSF protein, and traditional solvents, such as petroleum ether, n-hexane, and isopropanol, were chosen as controls. RESULTS: The meal degreased by aqueous ethyl acetate (the volume ratio of ethyl acetate to water is 90 to 10, EA + W10) shows a high degreasing rate (29.04%), crude protein content (562.3 g kg-1 ), essential amino acid index (EAAI, 95.57), and digestible indispensable amino acid score (DIAAS, 85). The digestibility of the degreased meal samples in the simulated in vitro intestine can reach 76.52%. Thermodynamic analysis and the apparent morphology of the protein fragments showed that the meal degreased by EA + W10 exhibited thermodynamic stability, which suggests that using aqueous ethyl acetate as the degreasing solvent did not affect the nutritional value of the degreased meal. CONCLUSION: The results suggest that aqueous ethyl acetate (EA + W10) can be used as a novel solvent in the degreasing of BSF larvae meal to prepare high-quality protein with high EAAI and DIAAS and good digestibility. © 2019 Society of Chemical Industry.


Assuntos
Acetatos/química , Manipulação de Alimentos/métodos , Larva/química , Simuliidae/química , Animais , Temperatura Alta , Valor Nutritivo
2.
J Sci Food Agric ; 100(3): 1038-1047, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31650558

RESUMO

BACKGROUND: The aquafeed sector has been replacing conventional dietary ingredients with more economic and eco-friendly ingredients. Insects embody a promising alternative as a result of being highly nutritious and showing traits leading to a circular bioeconomy. Atlantic salmon (Salmo salar L.) at the sea-water stage were fed diets with a partial or complete substitution of fishmeal with meal of Hermetia illucens larvae reared on a media containing Ascophyllum nodosum mixed with organic wastes (60:40). The present study aimed to assess the quality of fillets by characterizing its physico-chemical traits with conventional and innovative methods, such as the proton transfer reaction-time of flight-mass spectrometer technique, allowing the analysis of samples at room temperature. Finally, steamed fillets underwent a consumer test to investigate the liking of consumers and their intention of re-consumption. RESULTS: The main findings showed that a complete dietary substitution of fishmeal with H. illucens larvae meal did not impair the physico-chemical quality of A. salmon fillets. Notably, neutral n-3 polyunsaturated fatty acids (PUFA) slightly but significantly increased in the fillets of A. salmon fed H. illucens, also as a result of the additional fish oil present in the diets containing insect. The volatile organic profile was not altered by the different diets. The consumer-liking test revealed that Italian consumers appreciated the tested salmon irrespective of the administered feed. CONCLUSION: Tailoring the insect fatty acid profile by rearing the larvae on a PUFA-rich substrate, coupled with a dietary modulation of the oily source, can successfully maintain or even increase the cardioprotective characteristics of fillets. © 2019 Society of Chemical Industry.


Assuntos
Ração Animal/análise , Larva/química , Salmo salar/metabolismo , Compostos Orgânicos Voláteis/análise , Animais , Dieta/veterinária , Ácidos Graxos Insaturados/análise , Ácidos Graxos Insaturados/metabolismo , Pesqueiros , Larva/metabolismo , Carne/análise , Salmo salar/crescimento & desenvolvimento , Simuliidae/química , Simuliidae/metabolismo , Compostos Orgânicos Voláteis/metabolismo
3.
Parasitol Res ; 118(8): 2353-2359, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31263951

RESUMO

Simulium dermatitis is an IgE-mediated skin reaction in animals and humans caused by the bites of black flies. Although Simulium nigrogilvum has been incriminated as the main human-biting black fly species in Thailand, information on its salivary allergens is lacking. Salivary gland extract of S. nigrogilvum females was subjected to sodium dodecylsulfate-polyacrylamide gel electrophoresis, and the separated components were applied onto nitrocellulose membranes for immunoblotting, which was performed by probing the protein blots with sera from 17 individuals who were allergic to the bites of S. nigrogilvum. IgE-reactive protein bands were characterized further by liquid chromatography-mass spectrometry (LC-MS/MS) analysis. Nine protein bands (79, 42, 32, 25, 24, 22, 15, 13, and 11 kDa) were recognized in the serum of the subjects. Four of the nine protein bands (32, 24, 15, and 11 kDa) showed IgE reactivity in all (100%) of the tested sera, and they were identified as salivary secreted antigen 5-related protein, salivary serine protease, erythema protein, and hypothetical secreted protein, respectively. Three other proteins, salivary serine protease (25 kDa), salivary D7 secreted protein (22 kDa), and hypothetical protein (13 kDa), reacted with > 50% of the sera. The relevance of the identified protein bands as allergens needs to be confirmed by using pure recombinant proteins, either in the in vivo skin prick test or in vitro detection of the specific IgE in the serum samples of allergic subjects. This will be useful for the rational design of component-resolved diagnosis and allergen immunotherapy for the allergy mediated by the bites of black flies.


Assuntos
Mordeduras e Picadas/imunologia , Galectina 3/imunologia , Proteínas de Insetos/química , Glândulas Salivares/química , Simuliidae/fisiologia , Alérgenos/química , Alérgenos/imunologia , Animais , Mordeduras e Picadas/parasitologia , Cromatografia Líquida , Eletroforese em Gel de Poliacrilamida , Feminino , Galectina 3/química , Humanos , Imunoglobulina E/imunologia , Proteínas de Insetos/imunologia , Glândulas Salivares/imunologia , Simuliidae/química , Simuliidae/imunologia , Espectrometria de Massas em Tandem , Tailândia
4.
Meat Sci ; 153: 26-34, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30861487

RESUMO

Pork quality characteristics related to the dietary substitution of soybean meal by the micro-alga Spirulina (Arthrospira platensis) or black soldier fly (Hermetia illucens) partly-defatted larval meal were observed. Through a duplicated study totalling 48 individually-fed barrows (Pietrain × (Large White × Landrace)) allocated into two experimental groups and a control, the effect of dietary protein source on physico-chemical and sensory pork quality was monitored under current industrial packaging conditions (highly­oxygenated modified atmosphere packaging). The results show that physico-chemical characteristics are not degraded by including alternative protein sources in pig diets. Hermetia illucens increased lauric acid levels in backfat indicating that this fatty acid may be suitable as a biomarker for Hermetia illucens-fed pork. This goes to show that protein alternatives do not compromise pork quality.


Assuntos
Ração Animal/análise , Carne Vermelha/análise , Simuliidae/química , Spirulina/química , Tecido Adiposo/química , Fenômenos Fisiológicos da Nutrição Animal , Animais , Dieta/veterinária , Proteínas na Dieta , Larva/química , Ácidos Láuricos/análise , Masculino , Simuliidae/crescimento & desenvolvimento , Sus scrofa/crescimento & desenvolvimento
5.
Food Res Int ; 116: 276-282, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30716946

RESUMO

Black soldier fly (BSF, Hermetia illucens) represents a valuable source of biomolecules and it also constitutes an economic way to valorise residual biomasses. BSF prepupae contain high amounts of lipids (37% DM basis). The present investigation aimed at studying the composition of BSF lipids and the effect of killing/storage on their quality. The main fatty acid was lauric acid, sterols were represented primarily by beta-sitosterol and campesterol. Global fatty acid and sterol profiles, determined by GC-MS, were only slightly affected by the killing procedure, while lipid classes distribution, determined by 1H NMR, strongly changed. Prepupae killed by freezing showed a drastic reduction of acylglycerols during storage and a relevant release of free fatty acids, likely due to activation of lipases. On the contrary, prepupae killed by blanching have a stable lipid fraction constituted mainly by triacylglycerols. Therefore, killing procedure strongly influences BSF oil composition and the potential applications.


Assuntos
Manipulação de Alimentos/métodos , Homicídio , Lipídeos/análise , Simuliidae/química , Animais , Composição Corporal , Dípteros , Ácidos Graxos/análise , Congelamento , Glicerídeos/análise , Larva/química , Esteróis/análise
6.
Food Res Int ; 115: 116-125, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30599922

RESUMO

Insects are being explored as novel protein sources in order to overcome the future food demands connected to world growing population. Insects for food/feed uses are currently slowly killed through freezing by most insect rearing companies, and typically, enzymatic browning takes place in the insect proteins fractions. However, very little is known about the influence of these enzymatic reactions on the protein physical, chemical, nutritional and technological properties. In this work a metabolomics and proteomic study was conducted on Black Soldier Fly (Hermetia illucens) prepupae, killed by two different methods: freezing (commonly used), and blanching (with the aim to inhibit the enzymatic activities). Proton nuclear magnetic resonance (1H NMR) metabolomics demonstrated that slow killing method by freezing, compared with blanching, elicits the activation of several enzymatic pathways, among them melanisation with tyrosine consumption, energetic metabolism and lipolysis. These metabolic changes have an impact also on protein nutritional quality, with a loss of cysteine and lysine, likely involved in the process of melanisation and enzymatic browning. A strong effect was also observed on protein extractability: proteins from prepupae killed by blanching were found to be more extractable in milder conditions by chemical methods, and more prone to enzymatic digestion (97% of proteins released in solution upon proteolysis) than proteins from prepupae killed by freezing. All these data indicate that killing by blanching inhibits the browning reaction and other enzymatic changes occurring during slow killing by freezing, increasing the extractability of proteins in aqueous solutions, avoiding essential amino acid loss, and improving enzymatic digestibility.


Assuntos
Proteínas de Insetos/metabolismo , Reação de Maillard , Metabolômica , Proteômica , Simuliidae/química , Animais , Composição Corporal , Manipulação de Alimentos/métodos , Congelamento , Larva/química , Monofenol Mono-Oxigenase , Simuliidae/crescimento & desenvolvimento
7.
ACS Appl Mater Interfaces ; 10(49): 42127-42135, 2018 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-30451483

RESUMO

We report on the antibacterial and cytocompatibility properties of a bio-based electrospun polyhydroxyalkanoate (PHA) nanofiber modified with Black Soldier Fly (BSF) pupa shell. A 5-50 µm chitosan powder (CSP) was made by grinding BSF pupa shell in water, acid, alkali. CSP was combined with PHA in an electrospinning machine using a biaxial feed method and manufactured into a 50-500 nm antibacterial nanofiber. We studied the morphology, mechanical properties, water absorption, and antibacterial properties of the electrospun PHA/CSP nanofiber. To improve the fiber's compatibility and functionality, acrylic acid (AA) was grafted onto PHA. The resulting tensile properties and morphological characterizations indicated enhanced adhesion between CSP and PHA- g-AA nanofiber, as well as an improvement in its water resistance and tensile strength, compared with the PHA/CSP nanofiber. To study the cytocompatibility of the material, human foreskin fibroblasts were seeded onto the nanofiber specimens with 3.0 and 6.0 wt % CSP. Increasing the CSP content in PHA/CSP and PHA- g-AA/CSP nanofibers enhanced cell proliferation; additionally, the nanofibers with CSP showed strong inhibition of bacteria. The enhanced antibacterial and biodegradable properties of PHA- g-AA/CSP and PHA/CSP nanofibers demonstrate their potential for biomedical material applications.


Assuntos
Antibacterianos , Bactérias/crescimento & desenvolvimento , Materiais Biocompatíveis , Fibroblastos/metabolismo , Nanofibras/química , Poli-Hidroxialcanoatos/química , Simuliidae/química , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Quitosana/química , Quitosana/farmacologia , Fibroblastos/citologia , Humanos , Pupa/química
8.
J Sci Food Agric ; 98(15): 5776-5784, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29752718

RESUMO

BACKGROUND: Wastes can be used as rearing substrate by black soldier fly (BSF) larvae, the latter being exploitable as a protein source in animal feed. This research aimed to assess the influence of four rearing substrates (Trial 1 (organic wastes): a mixture of vegetable and fruit (VEGFRU) vs. a mixture of fruits only (FRU); Trial 2 (agro-industrial by-products): brewery (BRE) vs. winery (WIN) by-products) on BSF larvae development, waste reduction efficiency and nutritional composition. RESULTS: If respectively compared to FRU and WIN, VEGFRU and BRE larvae needed less time to reach the prepupal stage (22.0, 22.2, 20.2 and 8.0 days of trial, respectively) and had higher protein content (229.7, 257.3, 312.9 and 395.7 g kg-1 dry matter). The waste reduction index ranged from 2.4 (WIN) to 5.3 g d-1 (BRE). BRE larvae showed the lowest saturated and the highest polyunsaturated fatty acid proportions (612.4 and 260.1 g kg-1 total fatty acids, respectively). CONCLUSION: Vegetable and fruit wastes and winery by-products can be used as rearing substrates for BSF larval mass production. Brewery by-products led to very promising larval performance and nutritional composition. However, given BRE limited availability, low BRE dietary inclusion levels could be used with the purpose of increasing larval performance. © 2018 Society of Chemical Industry.


Assuntos
Larva/química , Simuliidae/crescimento & desenvolvimento , Resíduos/análise , Ração Animal/análise , Animais , Feminino , Frutas/química , Frutas/metabolismo , Larva/crescimento & desenvolvimento , Larva/metabolismo , Masculino , Simuliidae/química , Simuliidae/metabolismo , Verduras/química , Verduras/metabolismo
9.
Food Res Int ; 106: 420-427, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29579943

RESUMO

Edible insects are part of the diets of a significant proportion of rural populations in the tropics especially Africa and Asia, and their use as source of key nutrients for better nutrition is re-emerging. Indigenously, elemental methods are used to process the insects before they are consumed or sold in retail outlets. In recent years, better knowledge of processing, packaging and storage has become necessary because of commercialisation needs. A common processing approach involves drying after a brief heat-treatment step, and then milling into a powdered product which is sold to manufacturers or consumers as ingredient for processing final products. The hydration properties of dried powders of edible house cricket and black soldier fly larvae (BSFL) were studied with the aim of predicting shelf-life stability under typical packaging and storage temperatures experienced in the tropics. Moisture adsorption isotherms were determined gravimetrically at 25, 30 and 35 °C, over 0.11-0.97 water activity (aW) range, and the data fitted to various models. Sorption isotherms were of type II according to Brunauer classification indicating monolayer-multilayer sorption behaviour. Cricket powder exhibited higher hydration capacity, and aW of this product was less sensitive to temperature variation as compared to BSFL powder. In the two products, water exhibited transitions from bound- to free- state at ~5 g/100 g moisture content. Based on Heiss-Eichner model, a shelf-life of 7 months at 25 °C can be achieved if the cricket and BSFL powders are dried to ca. 5 g/100 g moisture content and packaged in 80 µm thick polyethylene films. At 35 °C the shelf-life of the cricket product is shortened three- to four-fold whereas the BSFL powder is unable to store.


Assuntos
Proteínas na Dieta/química , Manipulação de Alimentos/métodos , Embalagem de Alimentos/métodos , Conservação de Alimentos/métodos , Gryllidae/química , Proteínas de Insetos/química , Valor Nutritivo , Simuliidae/química , Água/química , Adsorção , Animais , Dessecação , Modelos Químicos , Polietileno/química , Pós , Temperatura Ambiente , Fatores de Tempo
10.
Artigo em Inglês | MEDLINE | ID: mdl-28278126

RESUMO

Edible insects have emerged as an alternative and sustainable source of high-quality, animal-derived protein and fat for livestock production or direct human nutrition. During the production of insects, substrate quality is a key parameter to assure optimal insect biomass gain as well as the safety of feed and food derived from commercially reared insects. Therefore, the influence of a realistic substrate contamination scenario on growth performance and accumulation behaviour of black soldier fly larvae (BSFL; Hermetia illucens L.) was investigated. Newly hatched larvae were fed on a corn-based substrate spiked with heavy metals (As, Cd, Cr, Hg, Ni, Pb), mycotoxins (aflatoxins B1/B2/G2, deoxynivalenol, ochratoxin A, zearalenone) and pesticides (chlorpyrifos, chlorpyrifos-methyl, pirimiphos-methyl) under defined breeding conditions (10 days, 28°C, 67% relative humidity). The extent of contaminants' bioaccumulation in the larval tissue as well as the effect on growing determinants were examined. The applied heavy metal substrate contamination was shown to impair larval growing indicated by significantly lower post-trial larval mass and feed conversion ratio (FCR). Cd and Pb accumulation factors of 9 and 2, respectively, were determined, while the concentrations of other heavy metals in the larvae remained below the initial substrate concentration. In contrast, mycotoxins and pesticides have neither been accumulated in the larval tissue nor significantly affected the growing determinants in comparison with the control. The use of BSFL as livestock feed requires contaminant monitoring - especially for Cd and Pb - in the substrates as well as in feedstuff containing BSFL to ensure feed and food safety along the value chain.


Assuntos
Ração Animal/análise , Cadeia Alimentar , Contaminação de Alimentos/análise , Metais Pesados/análise , Micotoxinas/análise , Praguicidas/análise , Simuliidae/química , Simuliidae/crescimento & desenvolvimento , Animais , Larva/química , Larva/crescimento & desenvolvimento
11.
Animal ; 10(12): 1923-1930, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27339654

RESUMO

In order to expand with validated scientific data the limited knowledge regarding the potential application of insects as innovative feed ingredients for poultry, the present study tested a partial substitution of soya bean meal and soya bean oil with defatted black soldier fly (Hermetia illucens) larvae meal (H) in the diet for growing broiler quails (Coturnix coturnix japonica) on growth performance, mortality, nutrients apparent digestibility, microbiological composition of excreta, feed choice, carcass and meat traits. With this purpose, a total of 450 10-day-old birds were allocated to 15 cages (30 birds/cage) and received three dietary treatments: a Control diet (C) and two diets (H1 and H2) corresponding to 10% and 15% H inclusion levels, respectively (H substituted 28.4% soya bean oil and 16.1% soya bean meal for H1, and 100% soya bean oil and 24.8% soya bean meal for H2, respectively). At 28 days of age, quails were slaughtered, carcasses were weighed, breast muscles were then excised from 50 quails/treatment, weighed, and ultimate pH (pHu) and L*, a*, b* colour values were measured. Breast muscles were then cooked to assess cooking loss and meat toughness. For the digestibility trial, a total of 15 28-day-old quails were assigned to the three feeding groups. The excreta samples were subjected to chemical and microbiological analysis. The same 15 quails were then simultaneously provided with C and H2 diets for a 10-day feed choice trial. Productive performance, mortality and carcass traits were in line with commercial standards and similar in all experimental groups. With the exception of ether extract digestibility, which was lower in H1 group compared with C and H2 (P=0.0001), apparent digestibility of dry matter, CP, starch and energy did not differ among treatments. Microbial composition of excreta was also comparable among the three groups. Feed choice trial showed that quails did not express a preference toward C or H2 diets. Breast meat weight and yield did not differ among C, H1 and H2 quails. Differently, the inclusion of H meal reduced meat pHu compared with C. In conclusion, this study demonstrated that H. illucens larvae meal can partially replace conventional soya bean meal and soya bean oil in the diet for growing broiler quails, thus confirming to be a promising insect protein source for the feed industry. Further research to assess the impact of H meal on intestinal morphology as well as on meat quality and sensory profile would be of utmost importance.


Assuntos
Ração Animal/análise , Dieta/veterinária , Proteínas na Dieta/análise , Carne/normas , Simuliidae/química , Fenômenos Fisiológicos da Nutrição Animal , Animais , Peso Corporal , Digestão/fisiologia , Larva/química , Músculos Peitorais , Codorniz/fisiologia , Soja
12.
PLoS One ; 10(3): e0118904, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25786206

RESUMO

The suite of pheromones that promote communal oviposition by Simulium vittatum, a North American black fly species, was identified and characterized using gas chromatography-mass spectrometry, electrophysiological, and behavioral bioassays. Behavioral assays demonstrated that communal oviposition was induced by egg-derived compounds that were active at short range and whose effect was enhanced through direct contact. Three compounds (cis-9-tetradecen-1-ol, 1-pentadecene, and 1-tridecene) were identified in a non-polar solvent extract of freshly deposited S. vittatum eggs that were capable of inducing the oviposition response. Electroantennography demonstrated that two of these three compounds (1-pentadecene and 1-tridecene) actively stimulated antennal neurons. Identification of the oviposition pheromones of this family may be helpful in developing control measures for nuisance black flies and for medically-important species such as Simulium damnosum sensu lato.


Assuntos
Oviposição/efeitos dos fármacos , Feromônios/análise , Feromônios/farmacologia , Simuliidae/química , Simuliidae/fisiologia , Alcenos/análise , Alcenos/farmacologia , Animais , Comportamento Animal/efeitos dos fármacos , Feminino , Insetos Vetores/química , Insetos Vetores/efeitos dos fármacos , Insetos Vetores/fisiologia , Masculino , Oncocercose Ocular/transmissão , Óvulo/efeitos dos fármacos , Óvulo/fisiologia , Simuliidae/efeitos dos fármacos , Solventes/química
13.
Parasit Vectors ; 8: 71, 2015 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-25649358

RESUMO

BACKGROUND: Black flies (Diptera: Simuliidae) are haematophagous insects that can cause allergic reactions and act as vectors of pathogens. Although their saliva has been thought to contain a diverse array of physiologically active molecules, little information is available on antimicrobial factors in black fly salivary glands, especially no defensins have been reported so far. METHODS: A novel cationic defensin designated SibaDef was purified using reverse phase high-performance liquid chromatography (RP-HPLC) from the salivary glands of the black fly Simulium bannaense. The amino acid sequence of SibaDef was determined by a combination method of automated Edman degradation and cDNA sequencing. The morphologic changes of Gram-positive bacteria Staphylococcus aureus or Bacillus subtilis treated with SibaDef were assessed by scanning electron microscopy (SEM). Quantitative PCR (qPCR) was performed to analyze the expression of SibaDef mRNA in whole bodies of insects after oral infection with the bacteria S. aureus or B. subtilis. RESULTS: Surprisingly, the phylogenetic analysis of defensin-related amino acid sequences demonstrated that SibaDef is most closely related to defensins from the human body louse Pediculus humanus corporis (Anoplura: Pediculidae), rather than to other dipteran defensins. SibaDef showed potent antimicrobial activities against Gram-positive bacteria with minimal inhibitory concentrations (MICs) ranging from 0.83 µM to 2.29 µM. SEM analysis indicated that SibaDef killed microorganisms through the disruption of cell membrane integrity. The transcript levels of SibaDef in the bacteria-immunized flies increased with the time course, reaching maximum at 36 h and then slowly decreased from that time point. CONCLUSIONS: Our results indicate that SibaDef is involved in the innate humoral response of the black fly S. bannaense, and it might play a significant role in the defence against microorganisms in both sugar and blood meals.


Assuntos
Defensinas/isolamento & purificação , Proteínas de Insetos/isolamento & purificação , Simuliidae/química , Sequência de Aminoácidos , Animais , Sequência de Bases , Defensinas/química , Defensinas/genética , Defensinas/imunologia , Proteínas de Insetos/química , Proteínas de Insetos/genética , Proteínas de Insetos/imunologia , Dados de Sequência Molecular , Filogenia , Glândulas Salivares/química , Glândulas Salivares/imunologia , Alinhamento de Sequência , Simuliidae/classificação , Simuliidae/genética , Simuliidae/imunologia
14.
Insect Biochem Mol Biol ; 43(12): 1181-1188, 2013 12.
Artigo em Inglês | MEDLINE | ID: mdl-24446544

RESUMO

The silks of arthropods have an elementary role in the natural history of the organisms that spin them, yet they are coded by rapidly evolving genes leading some authors to speculate that silk proteins are non-homologous proteins co-opted multiple times independently for similar functions. However, some general structural patterns are emerging. In this work we identified three major silk gland proteins using a combined biochemical, proteomic, next-generation sequencing and bioinformatic approach. Biochemical characterization determined that they were phosphorylated with multiple isoforms and potentially differential phosphorylation. Structural characterization showed that their structure was more similar to silk proteins from distantly related aquatic Trichopteran species than more closely related terrestrial or aquatic Diptera. Overall, our approach is easily transferable to any non-model species and if used across a larger number of aquatic species, we will be able to better understand the processes involved in linking the secondary structure of silk proteins with their function between in an organisms and its habitat.


Assuntos
Proteômica , Seda/química , Animais , Fosforilação , Estrutura Secundária de Proteína , Seda/genética , Simuliidae/química , Simuliidae/genética
15.
Neotropical Biology and Conservation ; 7(1): 48-56, Jan, 2012. tab, graf
Artigo em Português | Sec. Est. Saúde SP, SESSP-SUCENPROD, Sec. Est. Saúde SP | ID: ses-37568

RESUMO

O objetivo deste trabalho foi determinar a distribuição e a abundância de espécies do gênero Simulium em 5 córregos do litoral norte paulista, com diferentes níveis de poluição.Larvas de simulídeos e amostras de água de cada córrego foram coletadas quinzenalmente no verão e no inverno de 2001. Para a amostragem das larvas foram colocados substratos artificiais em triplicata. A cada intervalo de 15 dias as larvas foram retiradas com auxílio de pinças entomológicas, acondicionadas em frascos de vidro com álcool 70% e transportadas ao laboratório para triagem, contagem e identificação. Nos locais da coleta foram obtidos valores de temperatura, oxigênio, condutividade, pH da água e vazão do córrego e em laboratório as amostras de água foram analisadas, obtendo-se valor es de nitrogênio total e dissolvido, N-amoniacal, N-nitrito, N-nitrato, ortofosfato, fósforo total e dissolvido. Pode-se observar que a qualidade da água foi um fator determinante tanto para a distribuição como para a abundância das espécies. S. pertinax ocorreu em ambientesmais limpos, S. inaequale nos mais poluídos e S. incrustatum nos intermediários.A espécie predominante foi S. pertinax com 57,5% de presença total nos criadouros, S.inaequale com 42,1% e S. incrustatum com pouca representatividade, 0,4% de presençanas amostras. A menor abundância de larvas foi registrada nos ambientes poluídos...(AU)


The aim of this work was to determine the distribution and abundance the species of Simulium:in 5 streams of the north coastal region of the state of São Paulo. Simulium larval andwater samples were collected every 2 weeks in summer and winter, 2001. The larval werecollected on artificial substrates (triplicate) preserved in alcohol (70%) and after analyzedquantitative and qualitative. From the streams the values of temperature, dissolved oxygen,conductivity, pH and stream discharge were measured. The contents of total nitrogenand dissolved nitrogen, ammoniacal nitrogen, nitrate, nitrite, orthophosphate, dissolvedphosphorus and total phosphorus were determined in the laboratory. Water quality hasgreat influence in the distribution and abundance of the species. S. pertinax was moreabundant in streams without or with low levels of pollution, S. inaequale in streams morepolluted and S. incrustatum in intermediary levels of pollution. S. pertinax was the speciesmore abundant with 57.5% of presence in the samples, the second more abundant wasS. inaequale with 42.1% of presence and S. incrustatum was rare with 0.4% of presence.The larval abundance was lower in the polluted environment...(AU)


Assuntos
Animais , Simuliidae/crescimento & desenvolvimento , Simuliidae/química
16.
Mem Inst Oswaldo Cruz ; 105(2): 174-8, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20428677

RESUMO

In this study, anticoagulant activity was detected in salivary gland homogenates (SGHs) of Thyrsopelma guianense (Diptera: Simuliidae). The SGH yielded 1.07 microg +/- 0.03 (n = 15) of total soluble protein per pair of glands. In addition, following SDS-PAGE (12.5% gel) and silver nitrate staining, 12 polypeptides with molecular weights ranging from 14-69 kDa were detected in all physiological ages analyzed (12 h, 24 h, 48 h and 72 h following emergence). Coagulation bioassays showed that the SGHs had activities that interacted at all levels of coagulation (the intrinsic, extrinsic and common pathways), by extending the plasma recalcification time, prothrombin time, thrombin time. This is the first report on the activity of salivary gland proteins from the main vector of onchocerciasis in Brazil. We also suggest detailed studies on the morphology and function of the salivary glands in order to understand the role of these proteins in host/vector interactions.


Assuntos
Anticoagulantes/farmacologia , Proteínas de Insetos/farmacologia , Insetos Vetores/química , Glândulas Salivares/química , Simuliidae/química , Animais , Anticoagulantes/isolamento & purificação , Brasil , Eletroforese em Gel de Poliacrilamida , Feminino , Humanos , Proteínas de Insetos/isolamento & purificação , Oncocercose/transmissão , Fatores de Tempo
17.
Mem. Inst. Oswaldo Cruz ; 105(2): 174-178, Mar. 2010. ilus
Artigo em Inglês | LILACS | ID: lil-544623

RESUMO

In this study, anticoagulant activity was detected in salivary gland homogenates (SGHs) of Thyrsopelma guianense (Diptera: Simuliidae). The SGH yielded 1.07 ìg ± 0.03 (n = 15) of total soluble protein per pair of glands. In addition, following SDS-PAGE (12.5 percent gel) and silver nitrate staining, 12 polypeptides with molecular weights ranging from 14-69 kDa were detected in all physiological ages analyzed (12 h, 24 h, 48 h and 72 h following emergence). Coagulation bioassays showed that the SGHs had activities that interacted at all levels of coagulation (the intrinsic, extrinsic and common pathways), by extending the plasma recalcification time, prothrombin time, thrombin time. This is the first report on the activity of salivary gland proteins from the main vector of onchocerciasis in Brazil. We also suggest detailed studies on the morphology and function of the salivary glands in order to understand the role of these proteins in host/vector interactions.


Assuntos
Animais , Feminino , Humanos , Anticoagulantes/farmacologia , Proteínas de Insetos/farmacologia , Insetos Vetores/química , Glândulas Salivares/química , Simuliidae/química , Anticoagulantes/isolamento & purificação , Brasil , Eletroforese em Gel de Poliacrilamida , Proteínas de Insetos/isolamento & purificação , Oncocercose/transmissão , Fatores de Tempo
18.
Vet Immunol Immunopathol ; 132(1): 68-77, 2009 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-19836085

RESUMO

Insect bite hypersensitivity (IBH) is an allergic dermatitis of horses caused by bites of Culicoides and sometimes Simulium spp. The aim of this investigation was to identify Simulium allergens associated with IBH. A phage surface display cDNA library expressing recombinant Simulium vittatum salivary gland proteins was screened using sera of IBH-affected horses sensitized to S. vittatum salivary gland proteins as shown in immunoblot, resulting in the identification of seven cDNAs encoding IgE-binding proteins. The deduced amino acid sequences of these proteins showed sequence similarities to antigen 5 like protein (Sim v 1), to a serine protease inhibitor (Sim v 2), to two alpha-amylases (Sim v 3 and Sim v 4), and to three S. vittatum erythema proteins (SVEPs). The cDNA inserts were subcloned and expressed as [His](6)-tagged protein in Escherichia coli and purified using Ni(2+)-chelate affinity chromatography. Mice were immunised with the seven recombinant proteins and the antibodies tested against the recombinant proteins and salivary gland extract (SGE) of S. vittatum and Culicoides nubeculosus in immunoblot analyses. r-Sim v 1 specific mouse Abs recognized a band of about 32 kDa in immunoblots of both S. vittatum and C. nubeculosus SGE, detectable also by serum IgE of IBH-affected horses. Preincubation of horse serum with r-Sim v 1 completely inhibited IgE binding to the 32 kDa band demonstrating the presence of cross-reactive antigen 5 like proteins in both SGE. Determination of IgE levels against the r-Sim v proteins and crude S. vittatum extract by ELISA in sera from 25 IBH-affected and 20 control horses showed that IBH-affected horses had significantly higher IgE levels than controls against r-Sim v 1, 2, 3, 4 and S. vittatum extract, whereas the r-SVEP showed only marginal IgE binding. Further analyses showed that 60% of IBH-affected horses reacted to r-Sim v 1, suggesting that this could be a major allergen for IBH. Forty to twenty percent of the IBH-affected horses reacted with r-Sim v 2, 3 or 4. Combination of the results obtained with the 4 r-Sim v proteins showed that 92% of the IBH-affected but only 15% of the healthy horses had IgE levels against one or more of the 4 r-Sim v proteins. Seventy percent of the healthy horses had detectable IgE against S. vittatum extract, indicating a low specificity of the detection system used. Optimization of the ELISA system will be required to determine reliable cut-off values for the IBH-related allergens. Their in vivo relevance needs to be carefully assessed.


Assuntos
Alérgenos/imunologia , Doenças dos Cavalos/imunologia , Hipersensibilidade/veterinária , Imunoglobulina E/imunologia , Mordeduras e Picadas de Insetos/veterinária , Proteínas de Insetos/imunologia , Simuliidae/imunologia , Alérgenos/química , Alérgenos/genética , Alérgenos/isolamento & purificação , Sequência de Aminoácidos , Animais , Clonagem Molecular , Sequência Conservada , Bases de Dados de Ácidos Nucleicos , Ensaio de Imunoadsorção Enzimática , Cavalos , Hipersensibilidade/genética , Hipersensibilidade/imunologia , Mordeduras e Picadas de Insetos/genética , Mordeduras e Picadas de Insetos/imunologia , Proteínas de Insetos/química , Proteínas de Insetos/genética , Proteínas de Insetos/isolamento & purificação , Camundongos , Dados de Sequência Molecular , Alinhamento de Sequência , Simuliidae/química , Simuliidae/genética
19.
Vet Immunol Immunopathol ; 132(1): 62-7, 2009 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-19836841

RESUMO

Insect bite hypersensitivity (IBH) is an IgE-mediated allergic dermatitis of horses caused by bites of insects such as Culicoides or Simulium spp. The aim of the present study was to compare the IgE-binding pattern of sera of IBH-affected horses to Culicoides nubeculosus and Simulium vittatum salivary gland extracts (SGE). Individual IgE responses to proteins of S. vittatum and C. nubeculosus SGEs were evaluated in 15 IBH-affected and three healthy horses on immunoblots. Fourteen out of the 15 IBH-affected but none of the healthy horses showed individual IgE binding patterns to seven and six main protein bands in C. nubeculosus and S. vittatum SGE, respectively. These 14 sera showed IgE-binding to proteins from SGE of both C. nubeculosus and S. vittatum, but they reacted with fewer protein bands derived from S. vittatum than from C. nubeculosus SGE. Sera showing IgE-binding to a 32 kDa band from C. nubeculosus always bound to a 32 kDa band from S. vittatum. Similarly, all sera binding to a 70 kDa band from C. nubeculosus reacted with a corresponding band in S. vittatum SGE. The 70 kDa bands from S. vittatum and C. nubeculosus were identified by mass spectrometry as heat shock protein-70-cognate-3.


Assuntos
Ceratopogonidae/imunologia , Doenças dos Cavalos/imunologia , Hipersensibilidade/veterinária , Mordeduras e Picadas de Insetos/veterinária , Proteínas de Insetos/imunologia , Glândulas Salivares/imunologia , Simuliidae/imunologia , Alérgenos/química , Alérgenos/imunologia , Sequência de Aminoácidos , Animais , Ceratopogonidae/química , Proteínas de Choque Térmico HSP70/imunologia , Cavalos , Hipersensibilidade/imunologia , Hipersensibilidade/metabolismo , Imunoglobulina E/imunologia , Imunoglobulina E/metabolismo , Mordeduras e Picadas de Insetos/imunologia , Proteínas de Insetos/química , Dados de Sequência Molecular , Glândulas Salivares/química , Alinhamento de Sequência , Simuliidae/química
20.
J Vector Ecol ; 31(2): 406-11, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17249360

RESUMO

Saliva of female flies is responsible for localized hypersensitivity reactions and life-threatening systemic hemorrhagic syndromes in humans and animals. In this study, morphology and electrophoretic protein profiles of female salivary glands of Oriental black flies in the subgenus Simulium Latreille s. str., Simulium (Simulium) nigrogilvum, S. (S.) rufibasis, S. (S.) nodosum, and subgenus Gomphostilbia Enderlein, S. (Gomphostilbia) asakoae were analyzed. The paired female salivary glands of the four simuliid species were morphologically similar and situated on either side of the esophagus. Each gland is composed of two main parts, a secretory arm and a reservoir. In each species, the size of the gland correlated with salivary gland protein contents. SDS-PAGE analysis revealed differences of electrophoretic protein profiles and specifically major protein bands of the female salivary glands in each species, suggesting that protein profiles might be useful for construction of an additional tool to distinguish these black fly species. The information obtained from this study is an initial step for further research on salivary proteins that are involved in vertebrate hemostatic response.


Assuntos
Simuliidae/anatomia & histologia , Animais , Eletroforese em Gel de Poliacrilamida , Feminino , Proteínas de Insetos/análise , Glândulas Salivares/anatomia & histologia , Glândulas Salivares/química , Simuliidae/química , Especificidade da Espécie
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