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1.
Rev. bras. farmacogn ; 29(1): 69-76, Jan.-Feb. 2019. tab, graf
Artigo em Inglês | LILACS-Express | ID: biblio-990769

RESUMO

Abstract In this study, the adsorption/desorption characteristics of quercetin, luteolin and apigenin from Flos populi extract (Populus tomentosa Carrière, Salicaceae) on twelve macroporous resins (NKA-9, HPD-600, HPD-826, HPD-750, HPD-400, DM-130, AB-8, SP-825, X-5, D-101, HPD-100, HPD-200) were evaluated. Both high adsorption and desorption capacities of quercetin, luteolin and apigenin from Flos populi extract on SP-825 resin indicated that SP-825 resin was appropriate and its data were well fitted to the Langmuir and Freundlich isotherms. To get the optimal separation process, the influences of factors such as flow rates, loading sample volumes, concentrations of desorption solution were further investigated. Column packed with SP-825 resin was used to perform dynamic adsorption and desorption experiments. After one round of treatment, the contents of quercetin, luteolin and apigenin in the final products were 3.75-fold, 3.67-fold and 3.54-fold increased with recovery yields of 87.25, 85.19 and 82.22%, respectively. The results showed that the preparative enrichment of quercetin, luteolin and apigenin was available via adsorption and desorption on SP-825 resin. This method is a promising basis for the large-scale preparation of quercetin, luteolin and apigenin from Flos populi.


Assuntos
Quercetina , Apigenina , Luteolina , Adsorção , Populus
2.
Braz. J. Pharm. Sci. (Online) ; 55: e18114, 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1039045

RESUMO

The interest of this work is the discovery of new antimicrobial agents of plant origin to inhibit the formation of microbial biofilms. The present research was conducted to identify and quantify the phenolic compounds extracted from Populus nigra and Populus alba buds harvested in the area of Tizi-Ouzou (Algeria), and to evaluate their antimicrobial and antibiofilm activity. High performance liquid chromatography (HPLC) was performed to identify the phenolic compounds in the ethyl acetate fraction of P. nigra and the methanolic extracts of P. nigra and P. alba. The antimicrobial activity of the crude extracts and the fractions of these two species was tested against 11 microorganisms, using the disk diffusion method, while the antibiofilm effect of certain extracts was carried out in a 96-well microplate and on a biomaterial (catheter). HPLC analysis revealed the presence of 10 bioactive compounds. The main phenolic compounds identified in the three extracts were p-coumaric acid, ellagic acid, and Kaempferol. This study was able to demonstrate that the extracts of P. nigra and P. alba buds have interesting antimicrobial properties, with diameters ranging from 6.6 to 21.3 mm. In addition, extracts of P. nigra exhibited antibiofilm effects greater than 70%. Our results provide evidence for the antimicrobial and antibiofilm potential of bud extracts from both poplar species. Thus, these results will pave the way for further research on these two plants.


Assuntos
Extratos Vegetais , Biofilmes/classificação , Populus/anatomia & histologia , Anti-Infecciosos/farmacocinética , Cromatografia Líquida de Alta Pressão/instrumentação , Argélia/etnologia , Compostos Fenólicos/análise , Polifenóis/farmacocinética
3.
Braz. j. microbiol ; 49(supl.1): 236-245, 2018. graf
Artigo em Inglês | LILACS | ID: biblio-974331

RESUMO

ABSTRACT Salinity and alkalinity are major abiotic stresses that limit growth and development of poplar. We investigated biocontrol potential of saline- and alkaline-tolerant mutants of Trichoderma asperellum to mediate the effects of salinity or alkalinity stresses on Populus davidiana × P. alba var. pyramidalis (PdPap poplar) seedlings. A T-DNA insertion mutant library of T. asperellum was constructed using an Agrobacterium tumefaciens mediated transformation system; this process yielded sixty five positive transformants (T1-T65). The salinity tolerant mutant, T59, grew in Potato Dextrose Agar (PDA) containing up to 10% (1709.40 mM) NaCl. Under NaCl-rich conditions, T59 was most effective in inhibiting Alternaria alternata (52.00%). The alkalinity tolerant mutants, T3 and T5, grew in PDA containing up to 0.4% (47.62 mM) NaHCO3. The ability of the T3 and T5 mutants to inhibit Fusarium oxysporum declined as NaHCO3 concentrations increased. NaHCO3 tolerance of the PdPap seedlings improved following treatment with the spores of the WT, T3, and T5 strains. The salinity tolerant mutant (T59) and two alkalinity tolerant mutants (T3 and T5) generated in this study can be applied to decrease the incidence of pathogenic fungi infection under saline or alkaline stress.


Assuntos
Doenças das Plantas/microbiologia , Trichoderma/fisiologia , Cloreto de Sódio/metabolismo , Populus/crescimento & desenvolvimento , Álcalis/metabolismo , Alternaria/fisiologia , Antibiose , Doenças das Plantas/prevenção & controle , Estresse Fisiológico , Trichoderma/genética , Populus/microbiologia , Plântula/crescimento & desenvolvimento , Plântula/microbiologia
4.
Braz. j. microbiol ; 45(4): 1263-1270, Oct.-Dec. 2014. ilus, tab
Artigo em Inglês | LILACS | ID: lil-741276

RESUMO

Trichoderma spp is the cause of the green mold disease in mushroom cultivation production. Many disinfection treatments are commonly applied to lignocellulose substrates to prevent contamination. Mushroom growers are usually worried about the contaminations that may occur after these treatments during handling or spawning. The aim of this paper is to estimate the growth of the green mold Trichoderma sp on lignocellulose substrates after different disinfection treatments to know which of them is more effective to avoid contamination during spawning phase. Three different treatments were assayed: sterilization (121 ºC), immersion in hot water (60 and 80 ºC), and immersion in alkalinized water. Wheat straw, wheat seeds and Eucalyptus or Populus sawdust were used separately as substrates. After the disinfection treatments, bagged substrates were sprayed with 3 mL of suspension of conidia of Trichoderma sp (10(5) conidia/mL) and then separately spawned with Pleurotus ostreatus or Gymnopilus pampeanus. The growth of Trichoderma sp was evaluated based on a qualitative scale. Trichoderma sp could not grow on non-sterilized substrates. Immersions in hot water treatments and immersion in alkalinized water were also unfavorable treatments for its growth. Co- cultivation with mushrooms favored Trichoderma sp growth. Mushroom cultivation disinfection treatments of lignocellulose substrates influence on the growth of Trichoderma sp when contaminations occur during spawning phase. The immersion in hot water at 60 ºC for 30 min or in alkalinized water for 36 h, are treatments which better reduced the contaminations with Trichoderma sp during spawning phase for the cultivation of lignicolous species.


Assuntos
Agaricales/crescimento & desenvolvimento , Desinfecção/métodos , Trichoderma/crescimento & desenvolvimento , Álcalis/metabolismo , Anti-Infecciosos/metabolismo , Eucalyptus/microbiologia , Temperatura Alta , Populus/microbiologia , Temperatura , Trichoderma/efeitos dos fármacos , Trichoderma/efeitos da radiação , Triticum/microbiologia
5.
Biocell ; 31(1): 41-49, abr. 2007. tab, graf
Artigo em Inglês | LILACS | ID: lil-491536

RESUMO

An in vitro collection has been Established with selected European aspen from Palencia province (Spain). Currently, this collection includes 32 high quality clones, selected for their good bearing and healthy state. Most of them belong to different discrete local populations. Populus tremula L. was propagated in proliferation Aspen Culture Medium; they required subculture every 3 months. The purpose of this study was, therefore, to select a medium which allows the maintenance of 32 clones for a period longer than 3 months without subculture and to observe the behavior of those clones in 15 different culture medium compositions. Seven nodal cutting stem explants from each clone were cultured in parallel in the different media. One and three months after setting on the stem explants, the number and the size of shoots, the root size, the presence or absence of callus and the survival, were evaluated. The survival was monthly recorded during 8 months. Taking into account the explant development, four media were proposed for collection preservation. One of them, Ga, with a reduction of salts, sucrose, 6-benzoaminopurine, omitting adenine sulphate and 1-naphthalene acetic acid, is the most economical. Behavior observations of the 32 clones in the 15 medium compositions showed the influence of the genotype of the clones.


Assuntos
Árvores/crescimento & desenvolvimento , Células Clonais , Estruturas Vegetais/crescimento & desenvolvimento , Meios de Cultura/química , Populus/crescimento & desenvolvimento , Técnicas de Cultura , Preservação Biológica , Espanha
6.
Bol. micol ; 20: 57-61, dic. 2005. ilus
Artigo em Espanhol | LILACS | ID: lil-476865

RESUMO

Entre septiembre a diciembre del 2004 el Instituto Forestal y el Servicio Agrícola y Ganadero, en investigaciones conjuntas de estrategias de control biológico para Tremex fuscicornis Fabr. (Hym. Siricidae), se profundizó en el conocimiento de la asociación simbiótica que presenta esta avispa xilófaga con un hongo. T. fuscicornis, es una avispa taladradora del álamo que presenta en sus glándulas micangiales el micelio y esporas de un hongo asociado, el cual inyectado al árbol en el momento de la oviposición, causa su posterior decaimiento y biodegradación. Desde hembras adultas se obtuvieron los micangios que contenían micelio y artrosporas del hongo, estos fueron macerados y posteriormente sembrados en agar papa dextrosa, desarrollándose colonias fúngicas que formaron artrosporas. El micelio de estas colonias fue inoculado en varios tipos de sustratos vegetales esterillizados, en especial en trozas de álamo, donde se desarrollaron basidiocarpos, los que taxonómicamente correspondieron a Cerrena unicolor (Bull.) Murr., primer reporte para Chile de este basidiomicete.


Since september to december 2004,Instituto Forestal and Servicio Agrícola y Ganadero, while investigating together the strategies for the biological control of Tremex fuscicornis Fabr. (Hym.Siricidae), acquired thorough knowledge about the symbiotic association existing between this xylophagus wasp with a fungus. T. fuscicornis is a horntail wasp attacking poplar trees and which has in its mycangial glands the mycelium and spores of an associated fungus that once injected in the tree at the oviposition stage, causes its further decayand rottenness. Mycangia containing mycelium and arthrospores of this fungi were obtained from adult females. They were macerated and then cultivated inpotato dextrose agar (PDA) what resulted in fungal colonies that further formed arthrospores. The myceliumof these colonies was inoculated into different kinds of sterilized vegetal substrates, mainly in pieces of poplartrees, where basidiocarpes were developed, taxonomically corresponding to Cerrena unicolor (Bull.) Murr., thisbeing the first report on this basidiomycete in Chile.


Assuntos
Fungos/isolamento & purificação , Fungos/classificação , Insetos Vetores , Insetos , Populus/microbiologia , Chile
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