Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 21
Filtrar
Mais filtros










Intervalo de ano de publicação
1.
Bioprocess Biosyst Eng ; 47(5): 651-663, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38554182

RESUMO

During scaling of fermentations, choosing a bioreactor is fundamental to ensure the product's quality. This study aims to produce bioherbicides using Trichoderma koningiopsis fermentation, evaluating process parameters in an Airlift bioreactor. As a response, we quantified the production of enzymes involved in the bioherbicide activity (amylase, cellulase, laccase, lipase, and peroxidase). In addition, it evaluated the agronomic efficiency of the fermented extract optimized through tests that promoted soybean growth and nodulation, soybean seed germination, and in vitro phytopathogen control. As a result of optimizing the scaling bioprocess, it was possible to obtain an adequate fermentation condition, which, when applied to soybean seeds, had beneficial effects on their growth. It allowed the production of an enzyme cocktail. These results add a crucial biotechnological potential factor for the success of the optimized formulation in the Airlift bioreactor, in addition to presenting relevant results for the scientific community.


Assuntos
Reatores Biológicos , Glycine max , Trichoderma , Glycine max/metabolismo , Glycine max/crescimento & desenvolvimento , Trichoderma/crescimento & desenvolvimento , Trichoderma/metabolismo , Fermentação
2.
Bioprocess Biosyst Eng ; 46(12): 1729-1754, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37743409

RESUMO

This review aimed to show that bioherbicides are possible in organic agriculture as natural compounds from fungi and metabolites produced by them. It is discussed that new formulations must be developed to improve field stability and enable the commercialization of microbial herbicides. Due to these bottlenecks, it is crucial to advance the bioprocesses behind the formulation and fermentation of bio-based herbicides, scaling up, strategies for field application, and the potential of bioherbicides in the global market. In this sense, it proposed insights for modern agriculture based on sustainable development and circular economy, precisely the formulation, scale-up, and field application of microbial bioherbicides.


Assuntos
Herbicidas , Herbicidas/farmacologia , Herbicidas/metabolismo , Fungos/metabolismo , Fermentação , Agricultura
3.
Bioprocess Biosyst Eng ; 46(5): 665-679, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36795191

RESUMO

This study evaluated the bioherbicidal potential of wild fungi grown on microalgal biomass from the digestate treatment of biogas production. Four fungal isolates were used and the extracts were evaluated for the activity of different enzymes and characterized by gas chromatography coupled with mass spectrometry. The bioherbicidal activity was assessed by application on Cucumis sativus, and the leaf damage was visually estimated. The microorganisms showed potential as agents producing an enzyme pool. The obtained fungal extracts presented different organic compounds, most acids, and when applied to Cucumis sativus, showed high levels of leaf damage (80-100 ± 3.00%, deviation relative to the observed average damage). Therefore, the microbial strains are potential biological control agents of weeds, which, together with the microalgae biomass, offer the appropriate conditions to obtain an enzyme pool of biotechnological relevance and with favorable characteristics to be explored as bioherbicides, addressing aspects within the environmental sustainability.


Assuntos
Microalgas , Biomassa , Cromatografia Gasosa-Espectrometria de Massas , Biocombustíveis , Fungos , Extratos Vegetais
4.
Biotechnol Rep (Amst) ; 34: e00718, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35686010

RESUMO

Efficient Microorganisms (EM) are commonly used in organic crops; however, there are no studies on their effects on the production of citrus seedlings. The work aimed to evaluate the impact of applying the inoculants Native Efficient Microorganisms (NEM) and the commercial product EM1® in forming the seedling of the rootstock Poncirus trifoliata (L.) Raf and in the development of young plants of Sweet Orange "Valência" (Citrus sinensis (L.) Osbeck) and Murcott tangor (Citrus sinensis x Citrus reticulata Blanco). The inoculant based on efficient microorganisms from the homemade technology of capture and multiplication, native efficient microorganisms (NEM), showed greater microbial diversity when compared to the commercial product EM1®. The results obtained from the dry mass analysis of the Valência orange and Murcott tangor plants indicate that positive effects resulting from the use of EM1® and NEM inoculums can be obtained by cultivating the respective crops in a system with oat straw cover. It was observed that the use of efficient microorganisms, as microbial natural bioactive formulation, has potential use in citrus and that farmers with fewer resources will be able to produce the microorganisms on their properties.

5.
Acta sci., Biol. sci ; 42: e48714, fev. 2020. tab, map, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1460919

RESUMO

Meliponinae eusocial bees are among the most important pollinators in the Neotropics and their beekeeping has been growing as both recreational and economic activity. Information on the pollen preferences and niche overlap among species coexisting in the same location is still scarce. This study focused on the use of pollen resources by three native species of Meliponinae in the Atlantic Forest, Melipona quadrifasciata quadrifasciata (Lepeletier 1836), Scaptotrigona depilis (Moure 1942), and Tetragonisca angustula (Latreille 1811), at two different sites. The use of pollen resources was evaluated from reserves inside hives collected monthly between February 2015 and January 2016. It was also estimated the Mean Minimal Distance (Dm) traveled by the bees to obtain pollen. The bees differed regarding the diversity of pollen types, Dm, and proportion of pollen from different plant life-form. Local factor promoted differences only for Dm. M. q. quadrifasciata foraged a low diversity of pollen species and traveled greater distances with a higher proportion of trees plus palm species. Tetragonisca angustula foraged a higher diversity of pollen and flew shorter distances with a lower proportion of trees and palms. The species factor predominates over the local factor in the clustering pattern, based on pollen profile similarity.


Assuntos
Animais , Abelhas/anatomia & histologia , Pólen/anatomia & histologia , Pólen/citologia
6.
Environ Sci Pollut Res Int ; 26(32): 33014-33022, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31512133

RESUMO

Swine production chain generates residues with potential application in environmental processes. This study aimed at the use of swine hair as a potential biofilter for hexavalent chromium (Cr(VI)) removal from wastewater of tannery industry. The hair was pretreated using H2O2 in alkaline medium, and statistical analysis was carried out to evaluate the hair degradation, as well the Cr(VI) removal by the potential pretreated biofilter. The results showed 99% of Cr(VI) removal in 105 min of treatment in large pH range (1-10). Treated and untreated effluents were submitted to cytotoxicity study using vegetable and animal cells, demonstrating a significant reduction on toxicity to both cells. Therefore, swine hair demonstrated to be a promising residue for heavy metal removal on the perspective of an environmentally friendly technique.


Assuntos
Cromo/análise , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/análise , Animais , Peróxido de Hidrogênio/análise , Metais Pesados/análise , Suínos , Águas Residuárias/química
7.
Heliyon ; 5(5): e01676, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31193093

RESUMO

The prospection of bioherbicides has been an alternative to weed control, aiming at mitigating chemical risks to human, animal and environmental health due to extreme use of synthetic herbicides. In the present study, various fungi were isolated from plants with symptoms of fungal diseases for bioherbicide purposes against weeds (Urochloa plantaginea, Euphorbia heterophylla and Bidens pilosa). Fungi isolated were identified by molecular methods and enzymatic products obtained by fungi fermentation (cellulase, lipase, peroxidase, and amylase) were quantified. Bioherbicide selectivity study was performed on crops (soybean and corn), as well as on resistant weeds. Among the isolated fungi, Fusarium oxysporum, Fusarium ploriferatum, and Trichoderma koningiopsis presented bioherbicide potential. T. koningiopsis, in particular, presented the highest effect on Euphorbia heterophylla (popular name - Mexican fire plant), causing up to 60% of foliar damage, without presenting phytotoxicity against corn crop. New perspectives for weeds control and their use in corn crops were prospected, considering the bioherbicide selectivity described in this study.

8.
Bioprocess Biosyst Eng ; 41(6): 851-857, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29516167

RESUMO

In this study, we evaluated the concentration of lipases from Aspergillus niger using efficient and low-cost methods aiming at application in the treatment of waste cooking oils. The change in ionic strength of the medium by the addition of salt and precipitation with ethanol increased the specific activity from 2.90 to 28.50 U/mg, resulting in a purification factor of 9.82-fold. The use of acetone resulted in a specific activity of 33.63 U/mg, resulting in a purification factor of 11.60-fold. After that, the concentrated lipase was used in the hydrolysis of waste cooking oil and 753.07 and 421.60 µmol/mL of free fatty acids were obtained for the enzyme precipitated with ethanol and acetone, respectively. The hydrolysis of waste cooking oil catalyzed by homemade purified lipase in ultrasonic media can be considered a pretreatment of oil by converting a significant amount of triglycerides into free fatty acids.


Assuntos
Aspergillus niger/enzimologia , Proteínas Fúngicas/química , Lipase/química , Óleos de Plantas/química , Ácidos Graxos/química , Hidrólise , Gerenciamento de Resíduos
9.
An Acad Bras Cienc ; 89(1): 57-63, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28423073

RESUMO

The present study evaluated the purification of inulinase by changing the ionic strength of the medium by addition of NaCl and CaCl2 followed by precipitation with n-propyl alcohol or iso-propyl alcohol. The effects of the concentration of alcohols and the rate of addition of alcohols in the crude extract on the purification yield and purification factor were evaluated. Precipitation caused an activation of enzyme and allowed purification factors up to 2.4-fold for both alcohols. The purification factor was affected positively by the modification of the ionic strength of the medium to 0.5 mol.L-1 NaCl before precipitation with the alcohol (n-propyl or iso-propyl). A purification factor of 4.8-fold and an enzyme yield of 78.1 % could be achieved by the addition of 0.5 mol.L-1 of NaCl to the crude extract, followed by the precipitation with 50 % (v/v) of n-propyl alcohol, added at a flow rate of 19.9 mL/min.


Assuntos
Álcoois/química , Precipitação Química , Glicosídeo Hidrolases/química , Glicosídeo Hidrolases/isolamento & purificação , Concentração Osmolar , Cloreto de Cálcio/química , Meios de Cultura/química , Kluyveromyces/química , Kluyveromyces/isolamento & purificação , Valores de Referência , Reprodutibilidade dos Testes , Sais/química , Cloreto de Sódio/química , Solventes/química
10.
An. acad. bras. ciênc ; 89(1): 57-63, Jan,-Mar. 2017. tab
Artigo em Inglês | LILACS | ID: biblio-886625

RESUMO

ABSTRACT The present study evaluated the purification of inulinase by changing the ionic strength of the medium by addition of NaCl and CaCl2 followed by precipitation with n-propyl alcohol or iso-propyl alcohol. The effects of the concentration of alcohols and the rate of addition of alcohols in the crude extract on the purification yield and purification factor were evaluated. Precipitation caused an activation of enzyme and allowed purification factors up to 2.4-fold for both alcohols. The purification factor was affected positively by the modification of the ionic strength of the medium to 0.5 mol.L-1 NaCl before precipitation with the alcohol (n-propyl or iso-propyl). A purification factor of 4.8-fold and an enzyme yield of 78.1 % could be achieved by the addition of 0.5 mol.L-1 of NaCl to the crude extract, followed by the precipitation with 50 % (v/v) of n-propyl alcohol, added at a flow rate of 19.9 mL/min.


Assuntos
Concentração Osmolar , Precipitação Química , Álcoois/química , Glicosídeo Hidrolases/isolamento & purificação , Glicosídeo Hidrolases/química , Valores de Referência , Sais/química , Solventes/química , Kluyveromyces/isolamento & purificação , Kluyveromyces/química , Cloreto de Cálcio/química , Cloreto de Sódio/química , Reprodutibilidade dos Testes , Meios de Cultura/química
11.
Int J Biol Macromol ; 83: 30-3, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26616454

RESUMO

In this study the interference of potassium phosphate, sodium citrate, sodium chloride and sodium nitrate salts on protein quantification by Bradford's method was assessed. Potassium phosphate and sodium citrate salts are commonly used in aqueous two-phase systems for enzyme purification. Results showed that the presence of potassium phosphate and sodium citrate salts increase the absorbance of the samples, when compared with the samples without any salt. The increase in absorptivity of the solution induces errors on protein quantification, which are propagated to the calculations of specific enzyme activity and consequently on purification factor. The presence of sodium chloride and sodium nitrate practically did not affect the absorbance of inulinase, probably the metals present in the enzyme extract did not interact with the added salts.


Assuntos
Proteínas/química , Sais/química , Água/química , Citratos/química , Nitratos/química , Fosfatos/química , Compostos de Potássio/química , Cloreto de Sódio/química , Citrato de Sódio , Solubilidade
12.
Bioprocess Biosyst Eng ; 35(7): 1229-37, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22388740

RESUMO

This work is focused on the characterization of a commercial cellulase in terms of optimum pH and temperature, stability to pH and temperature and affinity of this enzyme to several substrates, determining the Michaelis-Menten parameters. Maximum activity of cellulase was obtained for the temperature range from 40 to 50 °C and pH from 5.2 to 5.5. Enzyme activity decreased only 15% after 150 h of reaction at temperatures between 30 and 50 °C. No loss of activity was observed at pH 5.0 and 5.5. The cellulase showed satisfactory results in the hydrolysis of agroindustrial substrates, since similar activity was verified on filter paper and other agroindustrial substrates.


Assuntos
Agricultura , Celulase/metabolismo , Celulase/antagonistas & inibidores , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , Hidrólise , Temperatura
13.
J Sci Food Agric ; 91(2): 273-7, 2011 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-20945512

RESUMO

BACKGROUND: The objective of this work was to evaluate the insecticidal and repellent effect of essential oils of Eucalyptus dunnii, E. saligna, E. benthamii, E. globulus and E. viminalis in the control of Sitophilus zeamais in maize grains. RESULTS: The essential oils chemical composition showed that the E. benthamii presents the cis-ocimene (56.88%) as major compound. Results permitted us to verify that the evaluated species presented different insecticidal action under Sitophilus zeamais. About 100% of mortality was achieved with doses of 65, 100 and 400 microL for E. dunnii, E. saligna and E. benthamii, respectively. After regression analysis the LD(50) values were calculated and E. dunnii was shown to be the most efficient (25.03 microL), followed by E. saligna (37.93 microL) and E. benthamii (121.09 microL). Using the previously calculated LD(50) values, the repellency activity was calculated, allowing us to conclude that all species presented significant values in terms of this important parameter. CONCLUSION: The essential oil of Eucalyptus sp. presented insecticidal and repellency against Sitophilus zeamais Motschulsky (Coleoptera, Curculionidae). Although from an economic point of view synthetic chemicals are still more frequently used as repellents, natural products (essential oils) have the potential to provide efficient and safer repellents for humans and the environment.


Assuntos
Alcenos/farmacologia , Eucalyptus/química , Inseticidas , Óleos Voláteis/farmacologia , Doenças das Plantas , Extratos Vegetais/farmacologia , Gorgulhos , Alcenos/análise , Animais , Grão Comestível , Inseticidas/análise , Dose Letal Mediana , Óleos Voláteis/isolamento & purificação , Extratos Vegetais/química , Análise de Regressão , Zea mays
14.
Environ Technol ; 31(4): 365-71, 2010 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-20450110

RESUMO

A sequential experimental design strategy is used to optimize the extraction of lead from slag. The slag is composed mainly of iron (= 60%) and lead (= 6%), and cannot be disposed of in conventional landfill due to its high lead content. The extraction of lead is based on the complexing properties of ethylenediaminetetra-acetic acid (EDTA), the iron being masked with fluoride ions. Atomic absorption spectroscopy (AAS) has been used for monitoring iron and lead concentrations. In a first step, Plackett-Burman PB-12 experimental design was used for screening the variables and for selecting those to be used. Two central composite designs (CCDs) were then carried out to determine the optimal conditions for lead extraction. The optimized experimental conditions were established to be: contact time with the fluoride solution 30 min; particle size of slag between 150 and 600 microm; molecular concentration of fluoride solution 2.4 x 10(-3) mol and of EDTA 5 x 10(-4) mol; pH 1.5; 8 h contact time with the EDTA solution; and temperature 60 degrees C. Under these experimental conditions the lead content was reduced by 57% compared with the raw sample.


Assuntos
Quelantes/química , Ácido Edético/química , Resíduos Industriais , Chumbo/isolamento & purificação , Gerenciamento de Resíduos/métodos , Concentração de Íons de Hidrogênio
15.
Acta sci., Biol. sci ; 32(1): 39-42, jan.-mar.2010. ilus, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1460633

RESUMO

A progeny of Cambona-4, a female maté plant (Ilex paraguariensis) selected by its agronomical characteristics and mild flavor, was evaluated using RAPD markers in order to identify its male parents. Using RAPD markers specifics of each one of the four potential males, the paternity of 84 out of 107 offsprings was confirmed. The majority of the offsprings (83.3%) were ascribed to pollen donor A, while male plants B, C, and D represented 11.9, 4.8, and 0%, respectively. The highly desirable agronomical characteristics and product quality of Cambona-4/pollen donor A offsprings, identified by RAPD markers, lead to the planting of an orchard Cambona-4 and pollinator A to obtain bi-clonal commercial seeds


Uma progênie da matriz feminina de erva-mate (Ilex paraguariensis) denominada Cambona-4, selecionada pelas suas características agronômicas e sabor suave, foi avaliada por marcadores RAPD para a identificação dos respectivos parentais masculinos. Usando-se fragmentos específicos de RAPD de cada um dos quatro polinizadores potenciais, a paternidade de 84 de 107 descendentes foi confirmada. A maioria dos descendentes (83,3%) foi atribuída ao polinizador A, enquanto os polinizadores B, C e D representaram 11,9; 4,8 e 0%, respectivamente. As características agronômicas e de qualidade do produto, oriundas da progênie Cambona-4/polinizador A, identificado pelos marcadores RAPD, direcionaram o plantio de um pomar a partir do cruzamento destas para obtenção de sementes comerciais biclonais.


Assuntos
Ilex paraguariensis , Polinização
16.
J Hazard Mater ; 172(2-3): 1677-80, 2009 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-19643541

RESUMO

The pyrometallurgic process that the exhausted batteries are submitted for the recovery of metallic lead generates great amount of a by-product called slag. The slag is composed mainly of iron ( approximately 60%) and lead ( approximately 6%), and this residue cannot be disposed in conventional landfill due to the high lead content. This work presents a new methodology for the extraction of lead from slag, based on the complexing effect of EDTA, a chelating ligand that has the ability to solubilize several heavy metals. As the iron (Fe(2+)/Fe(3+)) have a formation's constant with EDTA higher than the lead and is present in high concentrations in the samples, the fluoride ion (F(-)) was employed to mask the iron ions. The tests were carried out in a qualitative way, confirming the lead extraction by the formation of a yellow precipitate of lead iodide.


Assuntos
Conservação dos Recursos Naturais , Eletrônica , Chumbo/isolamento & purificação , Quelantes , Ácido Edético , Resíduos Industriais/prevenção & controle , Ferro/isolamento & purificação
17.
Rev. bras. entomol ; 53(2): 304-307, June 2009. graf, tab
Artigo em Português | LILACS | ID: lil-521144

RESUMO

Resistência de pragas a inseticidas, danos ao ambiente em função da poluição do solo e de recursos hídricos vem sendo observados pelo uso de inseticidas químicos no controle de pragas em grãos armazenados. Com o intuito de minimizar estes problemas, estão sendo estudadas alternativas como o uso de inseticidas botânicos. Este trabalho foi realizado com o objetivo de avaliar o efeito do óleo essencial de Tagetes patula L. sobre, Sitophilus zeamais Motschulsky, 1855 em milho sob condições de laboratório. O óleo essencial de T. patula foi obtido através de arraste a vapor com aparelho clevenger. A caracterização química dos compostos encontrados no óleo essencial de T. patula foi realizada através de cromatografia gasosa acoplado a espectrometria de massas, sendo observados: limoneno (37,05 por cento), terpinoleno (32,61 por cento), piperitone (14,40 por cento), eofitadieno (5,91 por cento), sabineno (2,88 por cento), trans-ocimeno (2,02 por cento), beta-cariofileno (1,98 por cento), farnesol (1,84 por cento) e alfa-pineno (1,30 por cento). Os insetos utilizados nos bioensaios foram mantidos em temperatura e umidade relativa controlada. Foram avaliados os efeitos do óleo essencial de T. patula sobre o comportamento (atratividade e/ou repelência) e atividade inseticida sobre adultos de S. zeamais através de dois bioensaios. Pelos resultados pode-se observar o efeito repelente e inseticida do óleo essencial de T. patula sobre S. zeamais, na concentração de 10 µL (p<0,0001 e p=0,02) sendo portanto, eficaz no controle de adultos de S. zeamais.


Countless problems due to the use of chemical insecticides for the control of pests in stored grains have been observed. In order to minimize these problems, alternative measures have been developed, including the use of botanical insecticides. This work was carried out with the objective of evaluating the effect of the essential oil of Tagetes patula L. on, Sitophilus zeamais (Mots., 1855) in corn kernels in laboratory conditions. The T. patula essential oil was obtained through hidrodestilation with the Clevenger device. The chemical characterization of the compounds found in the essential oil of T. patula was carried by gas chromatography connected to the mass spectrometer. The compounds found were: limonene (37.05 percent), terpinolene (32.61 percent), piperitone (14.40 percent), neophitadiene (5.91 percent), sabinene (2.88 percent), trans-ocimene (2.02 percent), beta-cariphilene (1.98 percent), farnesol (1.84 percent), and alpha-pinene (1.30 percent). The insects used in the bio-test were kept under controled temperature and relative humidity environment. Two bioassays were carried out to evaluate the effect of the essential oil of T. patula on the behavior (activity/repellence) and insecticide activity on adults of S. zeamais. The results showed that this essential oil was efficient (concentration of 10 µL) to control adults of S. zeamais adults.


Assuntos
Animais , Asteraceae , Controle de Insetos , Repelentes de Insetos , Óleos Voláteis , Folhas de Planta , Caules de Planta , Gorgulhos
18.
Braz. arch. biol. technol ; 51(1): 175-181, Jan.-Feb. 2008. graf
Artigo em Inglês | LILACS | ID: lil-482067

RESUMO

The use of compressed carbon towards extracting semi-volatile compounds present in maté leaves (Ilex paraguariensis St. Hil.) is due to the growing interest in mate constituents to develop new products in the cosmetic, pharmaceutical and food industries. The objective of this work was to assess the chemical distribution of semi-volatile compounds in 20 native populations of maté collected all over Brazil. The extracts of bulk samples (30 plants) of each population were obtained by the high-pressure carbon dioxide extraction technique, and analyzed by GC/MSD. The quantification of compounds (caffeine, theobromine, phytol, squalene, vitamin E, eicosane, pentatriacontane, and stigmasterol) showed significant variations within the different populations and compounds analyzed, which are not related to geographical origin or macroclimate characteristics. The results pointed out to the importance of genetic and local environmental factors on the chemical composition of this species.


A extração empregando dióxido de carbono a altas pressões em erva-mate (Ilex paraguariensis St. Hil.), tem sido justificada pelo crescente interesse desta matriz vegetal ou de parte de seus constituintes na formulação de novos produtos, tais como cosméticos e medicamentos, entre outros. Neste contexto, o objetivo do presente trabalho é avaliar a distribuição química de compostos semi-voláteis em 20 populações de erva-mate coletadas em toda área de distribuição desta espécie no Brasil. 30 plantas foram selecionadas para produzir a amostra de cada população. Os extratos de cada amostra foram obtidos por extração com dióxido de carbono a alta pressão e, posteriormente, foram analisados por CG/EM. A quantificação de alguns compostos semi-voláteis presentes nos extratos (cafeína, teobromina, fitol, esqualeno, vitamina E, eicosano, pentatriacontano e stigmasterol), apresentaram variações significativas entre as concentrações dos diferentes compostos analisados nas diferentes populações, os quais não estão relacionados com origem geográfica ou com características de macroclima. Os resultados apontam para a importância dos fatores genéticos e/ou fatores de microclima sobre a composição química desta espécie.

19.
Braz. j. microbiol ; 38(4): 610-616, Oct.-Dec. 2007. graf, tab
Artigo em Inglês | LILACS | ID: lil-473470

RESUMO

This work reports antimicrobial activity of oregano (Origanum vulgare) essential oil against several bacteria in sausage. The in vitro minimum inhibitory concentration (MIC) was determined for 9 selected aerobic heterotrofic bacteria. The antimicrobial activity of distinct concentrations of the essential oil on the basis of the highest MIC found was tested in a food system comprised of fresh sausage. Batch food samples were also inoculated with Escherichia coli with a fixed concentration and the time course of the product was evaluated with respect to the action of the different concentrations of essential oil. Sensory analysis were conducted, and results showed that the addition of oregano essential oil to sausage may be a promising route as bacteriostatic effect was verified for oil concentrations lower than the MIC.


O presente trabalho reporta resultados referentes à testes de atividade antimicrobiana do óleo essencial de orégano (Origanum vulgare) contra várias bactérias em lingüiça. A concentração inibitória mínima (CIM) foi determinada para 9 bactérias aeróbicas heterotróficas. Com base no maior valor encontrado da CIM, testou-se a atividade antimicrobiana para distintas concentrações do óleo essencial in lingüiça fresca. Amostras do sistema alimentar escolhido foram inoculadas com Escherichia coli numa determinada concentração e a evolução temporal do produto concernente ao crescimento microbiano foi monitorada avaliando-se o efeito das diferentes concentrações de óleos essencial aplicadas ao produto inoculado. Os resultados das análises microbiológica e sensorial mostraram que a adição do óleo essencial de orégano a linguiça fresca coloca-se como promissora tendo em vista os efeitos bacteriostáticos observados em baixas concentrações do óleo essencial, inferiores a CIM.

20.
J Agric Food Chem ; 52(7): 1990-5, 2004 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-15053541

RESUMO

The aim of this work is to assess the influence of light intensity (plants with direct sun exposure and in a controlled light intensity) and age of leaves (6-24 months) on the characteristics of the extracts of mate tea leaves obtained from carbon dioxide at high pressures. Samples of mate were collected in an experiment conducted under agronomic control at Industria e Comercio de Erva-Mate Barão LTDA, Brazil. The content of selected organic compounds of the extracts was evaluated by gas chromatography together with mass spectrometry. Quantitative analysis of caffeine, theobromine, phytol, vitamin E, squalene, and stigmasterol was performed, and the results showed that field variables exert a strong influence on the liquid yield and on the chemical distribution of the extracts.


Assuntos
Agricultura/métodos , Ilex paraguariensis/química , Extratos Vegetais/química , Folhas de Planta/química , Brasil , Dióxido de Carbono , Tecnologia de Alimentos , Luz , Pressão , Fatores de Tempo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...