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1.
Bull Entomol Res ; 106(5): 672-8, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27296280

RESUMEN

Despite the continued efforts on the search for different genotypes, Capsicum annuum (L.) is quite susceptible to attack by pest arthropods, especially the broad mite Polyphagotarsonemus latus Banks. Thus, the host preference, population growth and the injuries assessment of P. latus was studied on six C. annuum genotypes used in Brazil (Atlantis, California Wonder, Impact, Palloma, Rubia and Tendence). Host preference was accessed in choice tests, pairing the several genotypes, and the population growth was observed through non-choice tests in laboratory. The injuries assessments were evaluated in the greenhouse, comparing the injury level among the six genotypes. The results indicate that California Wonder and Palloma genotypes were more preferred by P. latus, and Impact and Tendence were less preferred. P. latus presented positive population growth rates (ri) on all the genotypes, however, Palloma and California Wonder showed the highest values of population growth rate (ri = 0.344 and ri = 0.340, respectively), while Impact had the lowest value (ri = 0.281). All the evaluated C. annuum genotypes showed low tolerance to P. latus and exhibited several injuries, but there was no statistical difference between them. California Wonder had the highest average number of mites/leaf (57.15), while Impact and Tendence obtained the lowest values (36.67 and 35.12, respectively) at the end of the evaluation period. The total average of injuries notes at the end of the bioassay did not differ between the genotypes. The number of mites/leaf was growing for the injury scale to the note 3.0, but when the injury scale approached the note 4.0, there was observed a decrease in the number of mites/leaf for all the genotypes.


Asunto(s)
Capsicum/fisiología , Herbivoria , Ácaros/fisiología , Animales , Brasil , Capsicum/genética , Preferencias Alimentarias , Genotipo , Especificidad del Huésped , Densidad de Población
2.
J Econ Entomol ; 109(2): 660-6, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26868417

RESUMEN

Spodoptera frugiperda (Smith 1797) (Lepidoptera: Noctuidae) is a major pest of maize, Zea mays L. Its control is often achieved through repeated applications per season of insecticides, which may lead to adverse effects on the ecosystem. Thus, the study of alternative methods with less environmental impact has expanded to include the use of essential oils. These oils are products of the secondary metabolism in plants, and their insecticidal activity has been widely demonstrated in populations of many pest insects. This study evaluated the insecticidal activities of essential oils from Eucalyptus staigeriana, Ocimum gratissimum, and Foeniculum vulgare on Spodoptera frugiperda. Gas chromatography­mass spectrometry profiles and contact toxicity of these oils as well as their sublethal effects on larvae and reproductive parameters in adults were evaluated. All three oils had sublethal effects on S. frugiperda; however, the oil of O. gratissimum showed the best results at all doses tested. These essential oils may have promise for control of S. frugiperda.


Asunto(s)
Eucalyptus/química , Foeniculum/química , Insecticidas/análisis , Ocimum/química , Aceites Volátiles/toxicidad , Spodoptera/efectos de los fármacos , Animales , Aceites Volátiles/química , Reproducción/efectos de los fármacos
3.
J Econ Entomol ; 107(1): 144-53, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24665696

RESUMEN

The combination of essential oils and Bacillus thuringiensis Berliner may represent an interesting control strategy. Thus, the study tested the following hypothesis: the combination of long pepper oil (Piper hispidinervum L.) and clove (Syzygium aromaticum L.) oils in two concentrations with Xentari WG (Bta) yields a more effective control of Spodoptera frugiperda (JE Smith) (Lepidoptera: Noctuidae) affecting biological and reproductive parameters and leading to changes in the levels of phenoloxidase and nitric oxide in the hemolymph of the pest. The results demonstrate that only long pepper oil, at the highest concentration with Xentari WG (Bta), promotes reduced larval survival. However, both oils with or without the insecticide interfere in the biology and humoral immunity of S.frugiperda. All treatments caused a decrease in the amount of eggs, except for the clove oil at both concentrations without Bta. Therefore, the use of these oils is a promising alternative for the integrated management of S. frugiperda; however, its association with Bta demonstrated no significant increase in their efficiency.


Asunto(s)
Conducta Alimentaria/efectos de los fármacos , Mariposas Nocturnas/efectos de los fármacos , Aceites Volátiles/toxicidad , Piper/química , Syzygium/química , Animales , Toxinas de Bacillus thuringiensis , Proteínas Bacterianas , Endotoxinas , Fertilidad/efectos de los fármacos , Hemolinfa/metabolismo , Proteínas Hemolisinas , Insecticidas , Monofenol Monooxigenasa/metabolismo , Mariposas Nocturnas/enzimología , Mariposas Nocturnas/crecimiento & desarrollo , Óxido Nítrico/metabolismo , Aceites Volátiles/química
4.
Neotrop Entomol ; 52(4): 652-696, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36656492

RESUMEN

In this contribution, supplementary descriptions of Cyphoderus innominatus Mills, 1938 and C. limboxiphius nitricola Rapoport & Izarra, 1962 are provided; and three new species are described: C. adversus sp. nov., C. amazonicus sp. nov., and C. parafolsomi sp. nov.; chaetotaxy for all of them is included. The new species have a labial triangular field with a1-5, m, e, l1 smooth chaetae, and l2 as reduced spine, but C. adversus sp. nov. is characterized by a trochateral organ with at least 9 spine-like chaetae; tenent hair capitate; colophore chaeta D mic, lateral flap chaetae with uneven length; dens with De1-De6/Di1-Di6 feathered chaetae; mucro only with a, while C. amazonicus sp. nov. is differentiated by a trochateral organ with at least 16 spine-like chaetae; tenent hair acuminate; colophore chaeta D mac, lateral flap chaetae small and subequal; dens with De1-De6/Di1-Di5 feathered chaetae; mucro with aA. Cyphoderus parafolsomi sp. nov. has trochateral organ with more than 14 spine-like chaetae; unguis with 1 unpaired internal tooth; tenent hair capitate; dens with De1-De6/Di1-Di5 feathered chaetae; mucro with aA. A key for identification of the Neotropical species is provided. Also, the paper describes the information about the association of Cyphoderus with different ant species, and a new taxonomic status for C. nitricola (Rapoport & Izarra, 1962) comb. nov.


Asunto(s)
Artrópodos , Animales
5.
Bioprocess Biosyst Eng ; 35(3): 351-8, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21779888

RESUMEN

Both stability and catalytic activity of two commercial immobilized lipases were investigated in the presence of different organic solvents in ultrasound-assisted system. In a general way, for Novozym 435, the use of ethanol as solvent led to a loss of activity of 35% after 10 h of contact. The use of iso-octane conducted to a gradual increase in lipase activity in relation to the contact time, reaching a maximum value of relative activity of 126%. For Lipozyme RM IM, after 5 h of exposure, the enzyme presented no residual activity when ethanol was used as solvent. The solvents tert-butanol and iso-octane showed an enhancement of about 20 and 17% in the enzyme activity in 6 h of exposure, respectively. Novozym 435 and Lipozyme IM presented high stability to storage after treatment under ultrasound-assisted system using n-hexane and tert-butanol as solvents.


Asunto(s)
Enzimas Inmovilizadas/química , Lipasa/química , Octanos/química , Solventes/química , Sonido , Proteínas Fúngicas , Temperatura , Factores de Tiempo
6.
Braz J Biol ; 81(3): 621-631, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-32876168

RESUMEN

Campomanesia xanthocarpa, a plant belonging to the Myrtaceae family, is popularly known as gabiroba. Leaves of gabiroba has been popularly used to treat various diseases, including inflammatory, renal, and digestive, among others. Additionally, studies have shown an effect to reduce blood cholesterol levels. The aim of this study was to evaluate the antihyperglycemic and hypolipidemic effects of Campomanesia xanthocarpa seed extract in hyperglycemic rats. The results showed that 400 mg/kg of seed extract was able to decrease blood glucose levels and to increase the muscular and hepatic glycogen content as well as to inhibit the sucrase and maltase activity. At doses of 200 mg/kg and 800 mg/kg, the activity of these enzymes was also reduced. In the lipid profile 400 mg/kg produced a decrease in total and LDL cholesterol serum levels; and with 200 mg/kg there was an increase in HDL cholesterol levels. The extract did not present hepatic and renal toxic effects at the different doses tested. The results suggest that the treatment with Campomanesia xanthocarpa seeds extract is useful in reducing glycemia, total cholesterol and LDL levels with potential adjuvant therapeutic in the treatment of diabetes and hypercholesterolemia, however, additional pharmacological and toxicological studies are still required.


Asunto(s)
Dióxido de Carbono , Myrtaceae , Animales , Hipoglucemiantes/farmacología , Extractos Vegetales/farmacología , Ratas , Semillas
7.
Braz J Biol ; 81(2): 291-300, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-32696852

RESUMEN

The use of medicinal plants for disease prevention, treatment and cure is an ancient practice used by humanity, and many plants species are used in bioprospecting research. In this context, its stands out Eugenia uniflora L., populary known as pitangueira and belongs to the Myrtaceae family, with a wide geographic distribution and native of Brazil. In view of the therapeutic qualities of the plant and the lack of the studies on its seeds, the present study had as objective to evaluate the phytochemical profile of the extracts of Eugenia uniflora L. seeds, from different solvents, as well as their antibacterial activity, antioxidant and its inhibitory effect of intestinal disaccharidases. Results showed a high content of phenolic compounds and total flavonoids, thus characterizing antioxidant activity, also highlighting the best bacteriostatic action for the Gram positive strain of Staphylococcus aureus in the ethanolic fraction. Regarding the disaccharidases, a strong inhibitory action was observed for all concentrations, evidencing a antihyperglycemic potential. The present research allowed to concluded that Eugenia uniflora L. seeds have promising biological activities for the industrial sector, but a more detailed investigation is needed regarding their bioactive compounds.


Asunto(s)
Eugenia , Antibacterianos/farmacología , Antioxidantes/farmacología , Brasil , Disacaridasas , Extractos Vegetales/farmacología , Semillas
8.
Braz J Biol ; 83: e244647, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34190758

RESUMEN

The essential oil of citronella (Cymbopogon winterianus) has several biological activities, among them the insect repellent action. Some studies showed that cinnamic acid esters can be applied as natural pesticides, insecticides and fungicides. In this context, the objective of the present work was to evaluate the production of esters from citronella essential oil with cinnamic acid via enzymatic esterification. Besides, the essential oil toxicity before and after esterification against Artemia salina and larvicidal action on Aedes aegypti was investigated. Esters were produced using cinnamic acid as the acylating agent and citronella essential oil (3:1) in heptane and 15 wt% NS 88011 enzyme as biocatalysts, at 70 °C and 150 rpm. Conversion rates of citronellyl and geranyl cinnamates were 58.7 and 69.0% for NS 88011, respectively. For the toxicity to Artemia salina LC50 results of 5.29 µg mL-1 were obtained for the essential oil and 4.36 µg mL-1 for the esterified oils obtained with NS 88011. In the insecticidal activity against Aedes aegypti larvae, was obtained LC50 of 111.84 µg mL-1 for the essential oil of citronella and 86.30 µg mL-1 for the esterified oils obtained with the enzyme NS 88011, indicating high toxicity of the esters. The results demonstrated that the evaluated samples present potential of application as bioinsecticide.


Asunto(s)
Aedes , Cymbopogon , Repelentes de Insectos , Insecticidas , Aceites Volátiles , Animales , Esterificación , Insecticidas/toxicidad , Larva , Aceites Volátiles/toxicidad
9.
Neotrop Entomol ; 49(3): 420-434, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32399957

RESUMEN

Two new species of Collembola are described, full body chaetotaxy is given. Ptenothrix dalii sp. nov. and Seira pietata sp. nov. were originally found in metalogenic areas covered with transitional vegetation of savanna and forest in Minas Gerais, Southeastern Brazil. Ptenothrix dalii sp. nov. is part of the "gracilis-group" of species, with large, blunt macrochaetae on head and body. Seira pietata sp. nov. is part of the "andensis-group" of species, lacking macrochaeta on abdominal segment I.


Asunto(s)
Insectos/anatomía & histología , Insectos/clasificación , Animales , Brasil , Cuevas , Bosques
10.
Lett Appl Microbiol ; 49(1): 60-6, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19422476

RESUMEN

AIMS: The objective of this work was to investigate the lipase production by a newly isolated Penicillium sp., using experimental design technique, in submerged fermentation using a medium based on peptone, yeast extract, NaCl and olive oil, as well as to characterize the crude enzymatic extracts obtained. METHODS AND RESULTS: Lipase activity values of 9.5 U ml(-1) in 96 h of fermentation was obtained at the maximized operational conditions of peptone, yeast extract, NaCl and olive oil concentrations (g l(-1)) of 20.0, 5.0, 5.0 and of 10.0 respectively. The partial characterization of crude enzymatic extract obtained by submerged fermentation showed optimum activity at pH range from 4.9 to 5.5 and temperature from 37 degrees C to 42 degrees C. The crude extract maintained its initial activity at freezing temperatures up to 100 days. CONCLUSIONS: A newly isolated strain of Penicillium sp. used in this work yielded good lipase activities compared to the literature. SIGNIFICANCE AND IMPACT OF THE STUDY: The growing interest in lipase production is related to the potential biotechnological applications that these enzymes present. New lipase producers are relevant to finding enzymes with different catalytic properties of commercial interest could be obtained, without using genetically modified organisms (GMO).


Asunto(s)
Proteínas Fúngicas/aislamiento & purificación , Proteínas Fúngicas/metabolismo , Lipasa/aislamiento & purificación , Lipasa/metabolismo , Penicillium/enzimología , Medios de Cultivo/química , Estabilidad de Enzimas , Congelación , Proteínas Fúngicas/química , Concentración de Iones de Hidrógeno , Lipasa/química , Penicillium/aislamiento & purificación , Temperatura
11.
Biotech Histochem ; 93(1): 36-48, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29205073

RESUMEN

The armyworm, Spodoptera frugiperda, is the principal pest of corn in Brazil. Control is achieved primarily by synthetic insecticides, which cause problems for the agro-ecosystem. Alternative methods of control are under investigation and citronella (Cymbopogon winterianus) essential oil appears to be a promising agent. We investigated the effects of citronella oil using histological, histochemical and immunohistochemical methods. The midgut of larvae treated with citronella exhibited altered epithelium including cytoplasmic protrusions, columnar cell extrusion, pyknotic nuclei, and increased periodic acid-Schiff positive granules. Regenerative cells in the epithelium of the midgut increased in number, which facilitated subsequent regeneration of this tissue. After exposure to citronella, trophocytes, the principal cell type of the fat body, possessed enlarged vacuoles and mitotic bodies, and contained reduced amounts of glycogen, lipid, and protein. Citronella oil caused morphological changes of the midgut and reduction of stored resources in the fat body, which may adversely affect insect reproduction and survival.


Asunto(s)
Sistema Digestivo/efectos de los fármacos , Aceites de Plantas/farmacología , Spodoptera/efectos de los fármacos , Animales , Bioensayo , Cromatografía de Gases , Relación Dosis-Respuesta a Droga , Cuerpo Adiposo , Espectrometría de Masas , Estándares de Referencia
12.
Braz. j. biol ; 83: 1-5, 2023. tab, graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1468822

RESUMEN

The essential oil of citronella (Cymbopogon winterianus) has several biological activities, among them the insect repellent action. Some studies showed that cinnamic acid esters can be applied as natural pesticides, insecticides and fungicides. In this context, the objective of the present work was to evaluate the production of esters from citronella essential oil with cinnamic acid via enzymatic esterification. Besides, the essential oil toxicity before and after esterification against Artemia salina and larvicidal action on Aedes aegypti was investigated. Esters were produced using cinnamic acid as the acylating agent and citronella essential oil (3:1) in heptane and 15 wt% NS 88011 enzyme as biocatalysts, at 70 °C and 150 rpm. Conversion rates of citronellyl and geranyl cinnamates were 58.7 and 69.0% for NS 88011, respectively. For the toxicity to Artemia salina LC50 results of 5.29 μg mL-¹ were obtained for the essential oil and 4.36 μg mL-¹ for the esterified oils obtained with NS 88011. In the insecticidal activity against Aedes aegypti larvae, was obtained LC50 of 111.84 μg mL-¹ for the essential oil of citronella and 86.30 μg mL-¹ for the esterified oils obtained with the enzyme NS 88011, indicating high toxicity of the esters. The results demonstrated that the evaluated samples present potential of application as bioinsecticide.


O óleo essencial de citronela (Cymbopogon winterianus) possui diversas atividades biológicas, entre elas a ação repelente a insetos. Alguns estudos mostraram que os ésteres do ácido cinâmico podem ser aplicados como pesticidas naturais, inseticidas e fungicidas. Nesse contexto, o objetivo do presente trabalho foi avaliar a produção de ésteres a partir do óleo essencial de citronela com ácido cinâmico via esterificação enzimática. Além disso, foi investigada a toxicidade do óleo essencial antes e após a esterificação contra Artemia salina e a ação larvicida sobre Aedes aegypti. Os ésteres foram produzidos utilizando ácido cinâmico como agente acilante e óleo essencial de citronela (3: 1) em heptano e 15% em peso da enzima NS 88011 como biocatalisadores, a 70 ° C e 150 rpm. As taxas de conversão de cinamatos de citronelil e geranil foram 58,7 e 69,0% para NS 88011, respectivamente. Para a toxicidade sobre Artemia salina foram obtidos CL50 de 5,29 μg mL-¹ para o óleo essencial e 4,36 μg mL-¹ para os óleos esterificados com NS 88011. Na atividade inseticida contra larvas de Aedes aegypti, obteve-se CL50 de 111,84 μg mL-¹ para o óleo essencial de citronela e 86,30 μg mL-¹ para os óleos esterificados com a enzima NS 88011, indicando alta toxicidade dos ésteres. Os resultados demonstraram que as amostras avaliadas apresentam potencial de aplicação como bioinseticida.


Asunto(s)
Animales , Aedes , Artemia , Cymbopogon/enzimología , Cymbopogon/toxicidad , Ésteres/toxicidad
13.
Braz. j. biol ; 832023.
Artículo en Inglés | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469038

RESUMEN

Abstract The essential oil of citronella (Cymbopogon winterianus) has several biological activities, among them the insect repellent action. Some studies showed that cinnamic acid esters can be applied as natural pesticides, insecticides and fungicides. In this context, the objective of the present work was to evaluate the production of esters from citronella essential oil with cinnamic acid via enzymatic esterification. Besides, the essential oil toxicity before and after esterification against Artemia salina and larvicidal action on Aedes aegypti was investigated. Esters were produced using cinnamic acid as the acylating agent and citronella essential oil (3:1) in heptane and 15 wt% NS 88011 enzyme as biocatalysts, at 70 °C and 150 rpm. Conversion rates of citronellyl and geranyl cinnamates were 58.7 and 69.0% for NS 88011, respectively. For the toxicity to Artemia salina LC50 results of 5.29 g mL-1 were obtained for the essential oil and 4.36 g mL-1 for the esterified oils obtained with NS 88011. In the insecticidal activity against Aedes aegypti larvae, was obtained LC50 of 111.84 g mL-1 for the essential oil of citronella and 86.30 g mL-1 for the esterified oils obtained with the enzyme NS 88011, indicating high toxicity of the esters. The results demonstrated that the evaluated samples present potential of application as bioinsecticide.


Resumo O óleo essencial de citronela (Cymbopogon winterianus) possui diversas atividades biológicas, entre elas a ação repelente a insetos. Alguns estudos mostraram que os ésteres do ácido cinâmico podem ser aplicados como pesticidas naturais, inseticidas e fungicidas. Nesse contexto, o objetivo do presente trabalho foi avaliar a produção de ésteres a partir do óleo essencial de citronela com ácido cinâmico via esterificação enzimática. Além disso, foi investigada a toxicidade do óleo essencial antes e após a esterificação contra Artemia salina e a ação larvicida sobre Aedes aegypti. Os ésteres foram produzidos utilizando ácido cinâmico como agente acilante e óleo essencial de citronela (3: 1) em heptano e 15% em peso da enzima NS 88011 como biocatalisadores, a 70 ° C e 150 rpm. As taxas de conversão de cinamatos de citronelil e geranil foram 58,7 e 69,0% para NS 88011, respectivamente. Para a toxicidade sobre Artemia salina foram obtidos CL50 de 5,29 g mL-1 para o óleo essencial e 4,36 g mL-1 para os óleos esterificados com NS 88011. Na atividade inseticida contra larvas de Aedes aegypti, obteve-se CL50 de 111,84 g mL-1 para o óleo essencial de citronela e 86,30 g mL-1 para os óleos esterificados com a enzima NS 88011, indicando alta toxicidade dos ésteres. Os resultados demonstraram que as amostras avaliadas apresentam potencial de aplicação como bioinseticida.

14.
Braz. j. biol ; 83: e244647, 2023. tab, graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1278527

RESUMEN

Abstract The essential oil of citronella (Cymbopogon winterianus) has several biological activities, among them the insect repellent action. Some studies showed that cinnamic acid esters can be applied as natural pesticides, insecticides and fungicides. In this context, the objective of the present work was to evaluate the production of esters from citronella essential oil with cinnamic acid via enzymatic esterification. Besides, the essential oil toxicity before and after esterification against Artemia salina and larvicidal action on Aedes aegypti was investigated. Esters were produced using cinnamic acid as the acylating agent and citronella essential oil (3:1) in heptane and 15 wt% NS 88011 enzyme as biocatalysts, at 70 °C and 150 rpm. Conversion rates of citronellyl and geranyl cinnamates were 58.7 and 69.0% for NS 88011, respectively. For the toxicity to Artemia salina LC50 results of 5.29 μg mL-1 were obtained for the essential oil and 4.36 μg mL-1 for the esterified oils obtained with NS 88011. In the insecticidal activity against Aedes aegypti larvae, was obtained LC50 of 111.84 μg mL-1 for the essential oil of citronella and 86.30 μg mL-1 for the esterified oils obtained with the enzyme NS 88011, indicating high toxicity of the esters. The results demonstrated that the evaluated samples present potential of application as bioinsecticide.


Resumo O óleo essencial de citronela (Cymbopogon winterianus) possui diversas atividades biológicas, entre elas a ação repelente a insetos. Alguns estudos mostraram que os ésteres do ácido cinâmico podem ser aplicados como pesticidas naturais, inseticidas e fungicidas. Nesse contexto, o objetivo do presente trabalho foi avaliar a produção de ésteres a partir do óleo essencial de citronela com ácido cinâmico via esterificação enzimática. Além disso, foi investigada a toxicidade do óleo essencial antes e após a esterificação contra Artemia salina e a ação larvicida sobre Aedes aegypti. Os ésteres foram produzidos utilizando ácido cinâmico como agente acilante e óleo essencial de citronela (3: 1) em heptano e 15% em peso da enzima NS 88011 como biocatalisadores, a 70 ° C e 150 rpm. As taxas de conversão de cinamatos de citronelil e geranil foram 58,7 e 69,0% para NS 88011, respectivamente. Para a toxicidade sobre Artemia salina foram obtidos CL50 de 5,29 μg mL-1 para o óleo essencial e 4,36 μg mL-1 para os óleos esterificados com NS 88011. Na atividade inseticida contra larvas de Aedes aegypti, obteve-se CL50 de 111,84 μg mL-1 para o óleo essencial de citronela e 86,30 μg mL-1 para os óleos esterificados com a enzima NS 88011, indicando alta toxicidade dos ésteres. Os resultados demonstraram que as amostras avaliadas apresentam potencial de aplicação como bioinseticida.


Asunto(s)
Animales , Aceites Volátiles/toxicidad , Aedes , Cymbopogon , Repelentes de Insectos , Insecticidas/toxicidad , Esterificación , Larva
15.
Sci Total Environ ; 605-606: 677-682, 2017 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-28675877

RESUMEN

This work demonstrates that cork used as oil-spill sorbents, contaminated with liquid hydrocarbons, herein demonstrated with hexadecane, can be biologically treated by Rhodococcus opacus B4 with concomitant lipids production. R. opacus B4 consumed up to 96% of hexadecane (C16) impregnated in natural and regranulated cork sorbents after 48h incubation, producing 0.59±0.06g of triacylglycerol (TAG) g-1 of C16 consumed with a TAG content of 0.60±0.06gg-1 of cellular dry weight (CDW) and 0.54±0.05g TAG g-1 of C16 consumed with a TAG content of 0.77±0.04gg-1 (CDW), respectively. TAG was mainly composed by fatty acids of 16 and 18 carbon chains demonstrating the feasibility of using it as raw material for biodiesel production. In addition, the obtained lipid-rich biomass (whole cells) can be used for biomethane production, at a yield of 0.4L CH4 g-1 (CDW). The obtained results support a novel approach for management of oil-spill contaminated cork sorbents through its valorisation by producing bacterial lipids, which can be used as feedstocks for biofuels production.


Asunto(s)
Biodegradación Ambiental , Biocombustibles , Hidrocarburos/metabolismo , Rhodococcus/metabolismo , Triglicéridos/química , Alcanos/metabolismo
16.
Environ Technol ; 38(23): 2928-2938, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28088876

RESUMEN

The separation of Jatropha curcas oil from azeotropes of ethyl alcohol-n-hexane and isopropyl alcohol-n-hexane using ceramic membranes with different cutoffs (5, 10 and 20 kDa) is presented. The mass ratios of oil:azeotropes (O:S) studied were 1:3 for feeding pressures of 0.1, 0.2 and 0.3 MPa, and 1:1 for the feeding pressure of 0.1 MPa. Isopropyl alcohol was the best solvent for the membranes conditioning to permeate n-hexane (240 kg/m2 h). In the separation of J. curcas oil and azeotropes of solvents, both membranes showed oil retention and total flux decreases with time. Overall, the lowest decrease in the retentions was reached in the 5 kDa membrane, while the lowest decrease in the total flux was reached in the 20 kDa. In the separation of oil and ethyl alcohol-n-hexane azeotrope, the best retention at 60 min of the process was equal to 17.3 wt% in the 20 kDa membrane at 0.3 MPa and O:S ratio equalled to 1:3. In this condition, the total permeate flux was 17.5 kg/m2 h. Different retentions and permeabilities are provided when changing the O:S ratio, the feeding pressure and the molecular weight cutoff of membranes.


Asunto(s)
Cerámica/química , Fraccionamiento Químico/métodos , Jatropha/química , Aceites de Plantas/aislamiento & purificación , Solventes/química , 2-Propanol/química , Hexanos/química , Membranas Artificiales , Aceites de Plantas/química
17.
Braz J Biol ; 66(4): 1045-9, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17299940

RESUMEN

The present research describes the histology of the midgut, gastric caeca, and pyloric valve of Tropidacris collaris (Stoll, 1813), (Orthopetera: Romaleidae). We used light microscopy, staining (Gomori's trichrome and periodic acid-Schiff (PAS)), and a routine histological analysis method (hematoxilin-eosin). The insects were obtained from, and also bred in, the Laboratory of Entomology, Department of Biology, of the Rural Federal University of Pernambuco (UFRPE). The collected material was fixed in alcoholic Botüin and embedded in paraplast. The results demonstrated that the midgut wall is composed of an inner epithelial layer and two outer layers of striate muscles: one internal (circular) and the other external (longitudinal), with connective tissue between the muscle fibers. The epithelium is single-layered, with two cell types: regenerative and elongated columnar. The gastric caeca presents muscle layers similar to those of the midgut. Simple columnar epithelium lines the gastric caeca, which presents villi and projects towards the lumen. The pyloric valve is of striate muscle tissue, covered by a single epithelial-cell layer.


Asunto(s)
Saltamontes/anatomía & histología , Mesenterio/anatomía & histología , Estómago/anatomía & histología , Animales , Saltamontes/citología , Mesenterio/citología , Estómago/citología
18.
Braz. j. biol ; 81(2): 291-300, 2021. tab, graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1153366

RESUMEN

The use of medicinal plants for disease prevention, treatment and cure is an ancient practice used by humanity, and many plants species are used in bioprospecting research. In this context, its stands out Eugenia uniflora L., populary known as pitangueira and belongs to the Myrtaceae family, with a wide geographic distribution and native of Brazil. In view of the therapeutic qualities of the plant and the lack of the studies on its seeds, the present study had as objective to evaluate the phytochemical profile of the extracts of Eugenia uniflora L. seeds, from different solvents, as well as their antibacterial activity, antioxidant and its inhibitory effect of intestinal disaccharidases. Results showed a high content of phenolic compounds and total flavonoids, thus characterizing antioxidant activity, also highlighting the best bacteriostatic action for the Gram positive strain of Staphylococcus aureus in the ethanolic fraction. Regarding the disaccharidases, a strong inhibitory action was observed for all concentrations, evidencing a antihyperglycemic potential. The present research allowed to concluded that Eugenia uniflora L. seeds have promising biological activities for the industrial sector, but a more detailed investigation is needed regarding their bioactive compounds.


A utilização de plantas com fins medicinais para prevenção, tratamento e cura de doenças é uma prática antiga utilizada pela humanidade, sendo que muitas espécies vegetais são usadas para a pesquisa da bioprospecção. Neste contexto, destaca-se a Eugenia uniflora L., conhecida popularmente como pitangueira e pertencente à família Myrtaceae, com ampla distribuição geográfica e nativa do Brasil. Diante das qualidades terapêuticas da planta e a falta de estudos sobre suas sementes, o presente trabalho teve como objetivo avaliar o perfil fitoquímico dos extratos das sementes de Eugenia uniflora L. a partir de diferentes solventes, bem como sua atividade antibacteriana, antioxidante e seu efeito inibidor de dissacaridases intestinais. Os resultados mostraram um alto teor de compostos fenólicos e flavonóides totais, caracterizando a atividade antioxidante, destacando também a melhor ação bacteriostática para a cepa Gram positiva de Staphylococcus aureus na fração etanólica. Em relação às dissacaridases, uma forte ação inibitória foi observada para todas as concentrações, evidenciando um potencial anti-hiperglicêmico. A presente pesquisa permitiu concluir que as sementes de Eugenia uniflora L. apresentam atividades biológicas promissoras para o setor industrial, mas é necessária uma investigação mais detalhada de seus compostos bioativos.


Asunto(s)
Semillas , Disacaridasas/antagonistas & inhibidores , Eugenia/química , Antibacterianos/farmacología , Antioxidantes/farmacología , Plantas Medicinales/química , Brasil , Extractos Vegetales/farmacología
19.
Braz. j. biol ; 81(3): 621-631, July-Sept. 2021. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1153391

RESUMEN

Abstract Campomanesia xanthocarpa, a plant belonging to the Myrtaceae family, is popularly known as gabiroba. Leaves of gabiroba has been popularly used to treat various diseases, including inflammatory, renal, and digestive, among others. Additionally, studies have shown an effect to reduce blood cholesterol levels. The aim of this study was to evaluate the antihyperglycemic and hypolipidemic effects of Campomanesia xanthocarpa seed extract in hyperglycemic rats. The results showed that 400 mg/kg of seed extract was able to decrease blood glucose levels and to increase the muscular and hepatic glycogen content as well as to inhibit the sucrase and maltase activity. At doses of 200 mg/kg and 800 mg/kg, the activity of these enzymes was also reduced. In the lipid profile 400 mg/kg produced a decrease in total and LDL cholesterol serum levels; and with 200 mg/kg there was an increase in HDL cholesterol levels. The extract did not present hepatic and renal toxic effects at the different doses tested. The results suggest that the treatment with Campomanesia xanthocarpa seeds extract is useful in reducing glycemia, total cholesterol and LDL levels with potential adjuvant therapeutic in the treatment of diabetes and hypercholesterolemia, however, additional pharmacological and toxicological studies are still required.


Resumo Campomanesia xanthocarpa, planta pertencente à família Mirtaceae, é popularmente conhecida como gabiroba. Folhas da gabiroba são popularmente usadas para tratar de doenças inflamatórias, renais, digestivas entre outras. Além disso, estudos têm mostrado um efeito redutor dos níveis de colesterol. O objetivo deste estudo foi avaliar os efeitos anti-hiperglicêmico e hipolipidêmico do extrato de sementes de Campomanesia xanthocarpa em ratos hiperglicêmicos. Os resultados mostraram que 400 mg/kg do extrato da semente foi capaz de reduzir os níveis de glicose sanguínea e aumentar o conteúdo de glicogênio hepático e muscular, bem como inibir a atividade da maltase e sacarase. Na dose de 200 mg/kg e 800 mg/kg, a atividade das enzimas também foi reduzida. No perfil lipídico, 400 mg/kg produziu uma redução nos níveis séricos de colesterol total e LDL e com 200 mg/kg houve um aumento nos níveis de colesterol HDL. O extrato não apresentou efeitos tóxicos hepáticos e renais nas doses testadas. Os resultados sugerem que o tratamento com o extrato de Campomanesia xanthocarpa é eficaz na redução da glicemia, de colesterol total e LDL com potencial para tratamento adjuvante do diabetes e hipercolesterolemia, no entanto estudos farmacológicos e toxicológicos adicionais são necessários.


Asunto(s)
Animales , Ratas , Dióxido de Carbono , Myrtaceae , Semillas , Extractos Vegetales/farmacología , Hipoglucemiantes/farmacología
20.
Transplant Proc ; 48(2): 512-5, 2016 03.
Artículo en Inglés | MEDLINE | ID: mdl-27109989

RESUMEN

BACKGROUND: The goal of this study was to investigate whether exogenous offer of L-arginine (LARG) modulates the gene expression of intestinal dysfunction caused by ischemia and reperfusion. METHODS: Eighteen Wistar-EPM1 male rats (250-300 g) were anesthetized and subjected to laparotomy. The superior mesenteric vessels were exposed, and the rats were randomized into 3 groups (n = 6): the control group (CG), with no superior mesenteric artery interruption; the ischemia/reperfusion group (IRG), with 60 minutes of ischemia and 120 minutes of reperfusion and saline injections; and the L-arginine group (IRG + LARG), with L-arginine injected in the femoral vein 5 minutes before ischemia, 5 minutes after reperfusion, and after 55 minutes of reperfusion. The total RNA was extracted and purified from samples of the small intestine. The concentration of each total RNA sample was determined by using spectrophotometry. The first-strand complementary DNA (cDNA) was synthesized in equal amounts of cDNA and the Master Mix SYBR Green qPCR Mastermix (SABiosciences, a Qiagen Company, Frederick, Md). Amounts of cDNA and Master Mix SYBR Green qPCR Mastermix were distributed to each well of the polymerase chain reaction microarray plate containing the predispensed gene-specific primer sets for Bax and Bcl2. Each sample was evaluated in triplicate, and the Student t test was applied to validate the homogeneity of each gene expression reaction (P < .05). RESULTS: The gene expression of Bax in IRG (+1.48) was significantly higher than in IRG-LARG (+9.69); the expression of Bcl2L1 in IRG (+1.01) was significantly higher than IRG-LARG (+22.89). CONCLUSIONS: The apoptotic cell pathway of 2 protagonists showed that LARG improves the gene expression of anti-apoptotic Bcl2l1 (Bcl2-like 1) more than the pro-apoptotic Bax (Bcl2-associated X protein).


Asunto(s)
Arginina/farmacología , Intestino Delgado/irrigación sanguínea , Intestino Delgado/metabolismo , Isquemia/metabolismo , Daño por Reperfusión/metabolismo , Proteína X Asociada a bcl-2/metabolismo , Animales , Apoptosis , Intestino Delgado/patología , Isquemia/complicaciones , Isquemia/patología , Masculino , Arteria Mesentérica Superior , ARN Mensajero/genética , ARN Mensajero/metabolismo , Distribución Aleatoria , Ratas , Ratas Wistar , Daño por Reperfusión/etiología , Daño por Reperfusión/patología , Proteína X Asociada a bcl-2/genética
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