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1.
ACS Appl Mater Interfaces ; 9(27): 22568-22577, 2017 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-28603967

RESUMO

Cellulose, which is one of the most-abundant and -renewable natural resources, has been extensively explored as an alternative substance for electrode materials such as activated carbons. Here, we demonstrate a new class of coffee-mediated green activation of cellulose as a new environmentally benign chemical-activation strategy and its potential use for all-paper flexible supercapacitors. A piece of paper towel is soaked in espresso coffee (acting as a natural activating agent) and then pyrolyzed to yield paper-derived activated carbons (denoted as "EK-ACs"). Potassium ions (K+), a core ingredient of espresso, play a viable role in facilitating pyrolysis kinetics and also in achieving a well-developed microporous structure in the EK-ACs. As a result, the EK-ACs show significant improvement in specific capacitance (131 F g-1 at a scan rate of 1.0 mV s-1) over control ACs (64 F g-1) obtained from the carbonization of a pristine paper towel. All-paper flexible supercapacitors are fabricated by assembling EK-ACs/carbon nanotube mixture-embedded paper towels (as electrodes), poly(vinyl alcohol)/KOH mixture-impregnated paper towels (as electrolytes), and polydimethylsiloxane-infiltrated paper towels (as packaging substances). The introduction of the EK-ACs (as an electrode material) and the paper towel (as a deformable and compliant substrate) enables the resulting all-paper supercapacitor to provide reliable and sustainable cell performance as well as exceptional mechanical flexibility. Notably, no appreciable loss in the cell capacitance is observed after repeated bending (over 5000 cycles) or multiple folding. The coffee-mediated green activation of cellulose and the resultant all-paper flexible supercapacitors open new material and system opportunities for eco-friendly high-performance flexible power sources.

2.
Int J Mol Med ; 36(2): 463-72, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26035417

RESUMO

Chamaecyparis obtusa has been traditionally used as an antibiotic agent and in cosmetics for the prevention of microorganism infection and skin troubles. Atopic dermatitis (AD) is a chronic inflammatory skin disease that encompasses immunologic responses, susceptibility factors and compromised skin-barrier function. Use of plant medicines in therapeutic treatment of AD has recently been suggested as an alternative therapeutic option. The present study examined the effect of elemol, an active component of Chamaecyparis obtusa, on AD using in vivo and in vitro models. RBL-2H3 cells were stimulated with concanavalin A and dinitrophenyl human serum albumin, and atopic dermatitis was induced in BALB/c mice by topical application of 2,4-dinitrochlorobenzene (DNCB) prior to elemol treatment. The mRNA expression was evaluated by reverse transcription quantitative polymerase chain reaction, and the levels of ß-hexosaminidase and serum immunoglobulin E (IgE) were examined by ELISA. Histological changes were also performed by microscopy. Elemol attenuated the onset of AD-like skin lesions, reduced serum IgE levels and decreased mast cell infiltration into the dermis and hypodermis. In addition, elemol downregulated the transcriptional expression of several pro-inflammatory cytokines, including TNF-α, IL-1ß, IL-6 and IκBα, in the skin of the DNCB-induced animal models of AD. In the RBL-2H3 mast cell line, elemol significantly inhibited the mRNA expression of IL-4 and IL-13, and further attenuated the release of ß-hexosaminidase from mast cells. Histological examination revealed that elemol significantly ameliorated the DNCB-induced dermal destruction in mice. The results of the present study suggested that elemol may have therapeutic potential in the treatment of AD due to its immunosuppressive effects.


Assuntos
Chamaecyparis/química , Dermatite Atópica/induzido quimicamente , Dermatite Atópica/tratamento farmacológico , Dinitroclorobenzeno , Sesquiterpenos/uso terapêutico , Pele/efeitos dos fármacos , Pele/patologia , Animais , Linhagem Celular , Citocinas/análise , Dermatite Atópica/sangue , Dermatite Atópica/patologia , Humanos , Imunoglobulina E/sangue , Masculino , Camundongos Endogâmicos BALB C , Óleos Voláteis/química , Óleos Voláteis/uso terapêutico , Sesquiterpenos/química
3.
Mol Med Rep ; 12(1): 345-50, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25760811

RESUMO

Aromatherapy has been suggested as an alternative therapeutic method for the treatment of atopic dermatitis (AD), eczema and other skin diseases. In the current study, the anti-atopic properties of the volatile organic compounds of Chamaecyparis obtusa (VOCCo) were examined to determine whether they are amenable for use as a pharmaceutical candidate. The alterations in histological features, serum IgE levels and mast cell infiltration following exposure to VOCCo were determined in a 2,4-dinitrochlorobenzene (DNCB)-induced AD-like mouse model. The results of these experiments demonstrated that VOCCo inhibited the development of AD-like skin lesions by reducing the serum IgE level and mast cell infiltration into the dermal and subcutaneous layers. This was supported by screening of immune cytokine mRNAs, including interleukin (IL)-1ß and IL-6 from the skin of DNCB-treated mice. The expression of IL-1ß and IL-6 in the skin lesions of mice was dose-dependently inhibited by treatment with VOCCo. Furthermore, treatment with VOCCo resulted in the recovery of histopathological features in AD-like skin lesions. These results suggest that VOCCo may have therapeutic and preventive effects for the development of AD.


Assuntos
Chamaecyparis/química , Dermatite Atópica/patologia , Extratos Vegetais/farmacologia , Pele/efeitos dos fármacos , Compostos Orgânicos Voláteis/farmacologia , Animais , Chamaecyparis/metabolismo , Dermatite Atópica/induzido quimicamente , Dermatite Atópica/terapia , Dinitroclorobenzeno/toxicidade , Modelos Animais de Doenças , Regulação da Expressão Gênica/efeitos dos fármacos , Imunoglobulina E/sangue , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Interleucina-6/genética , Interleucina-6/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , RNA Mensageiro/metabolismo , Pele/metabolismo , Pele/patologia , Compostos Orgânicos Voláteis/isolamento & purificação
4.
Nano Lett ; 14(10): 5677-86, 2014 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-25226349

RESUMO

The rapidly approaching smart/wearable energy era necessitates advanced rechargeable power sources with reliable electrochemical properties and versatile form factors. Here, as a unique and promising energy storage system to address this issue, we demonstrate a new class of heterolayered, one-dimensional (1D) nanobuilding block mat (h-nanomat) battery based on unitized separator/electrode assembly (SEA) architecture. The unitized SEAs consist of wood cellulose nanofibril (CNF) separator membranes and metallic current collector-/polymeric binder-free electrodes comprising solely single-walled carbon nanotube (SWNT)-netted electrode active materials (LiFePO4 (cathode) and Li4Ti5O12 (anode) powders are chosen as model systems to explore the proof of concept for h-nanomat batteries). The nanoporous CNF separator plays a critical role in securing the tightly interlocked electrode-separator interface. The SWNTs in the SEAs exhibit multifunctional roles as electron conductive additives, binders, current collectors and also non-Faradaic active materials. This structural/physicochemical uniqueness of the SEAs allows significant improvements in the mass loading of electrode active materials, electron transport pathways, electrolyte accessibility and misalignment-proof of separator/electrode interface. As a result, the h-nanomat batteries, which are easily fabricated by stacking anode SEA and cathode SEA, provide unprecedented advances in the electrochemical performance, shape flexibility and safety tolerance far beyond those achievable with conventional battery technologies. We anticipate that the h-nanomat batteries will open 1D nanobuilding block-driven new architectural design/opportunity for development of next-generation energy storage systems.

5.
Phytochemistry ; 82: 15-21, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22884779

RESUMO

In this study, dehydrogenative polymers (DHP) were synthesized in vitro through dehydrogenative polymerization using different ratios of coniferyl alcohol (CA) and sinapyl alcohol (SA) (10:0, 8:2, 6:4, 2:8, 0:10), in order to investigate the monolignol coupling mechanism in the presence of horseradish peroxidase (HRP), Coprinus cinereus peroxidase (CiP) or soybean peroxidase (SBP) with H(2)O(2), respectively. The turnover capacities of HRP, CiP and SBP were also measured for coniferyl alcohol (CA) and sinapyl alcohol (SA), and CiP and SBP were found to have the highest turnover capacity for CA and SA, respectively. The yields of HRP-catalyzed DHP (DHP-H) and CiP-catalyzed DHP (DHP-C) were estimated between ca. 7% and 72% based on the original weights of CA/SA in these synthetic conditions. However, a much lower yield of SBP-catalyzed DHP (DHP-S) was produced compared to that of DHP-H and DHP-C. In general, the DHP yields gradually increased as the ratio of CA/SA increased. The average molecular weight of DHP-H also increased with increasing CA/SA ratios, while those of DHP-C and DHP-S were not influenced by the ratios of monolignols. The frequency of ß-O-4 linkages in the DHPs decreased with increasing CA/SA ratios, indicating that the formation of ß-O-4 linkages during DHP synthesis was influenced by peroxidase type.


Assuntos
Hidrogênio/química , Peroxidase/metabolismo , Fenóis/química , Fenilpropionatos/química , Polimerização , Biocatálise , Coprinus/enzimologia , Peroxidase do Rábano Silvestre/metabolismo , Peróxido de Hidrogênio/química , Peso Molecular , Glycine max/enzimologia
6.
Bioresour Technol ; 104: 687-94, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22088658

RESUMO

This study employed thermogravimetric analysis (TGA) and analytical Py-GC/MS in order to examine the catalytic effect of main inorganic metals (K, Mg and Ca) on the thermal degradation and the formation of pyrolytic products in lignocellulosic biomass. In addition, potential mechanisms of the primary pyrolysis in presence of the inorganic metals were derived. TG analysis showed that when potassium content increased in the biomass, char formation increased from 10.5 wt.% to 19.6 wt.% at 550 °C, and temperatures at which the maximum degradation rate was achieved shifted from 367 °C to 333 °C. With increasing magnesium content, the maximum degradation rate increased from 1.21 wt.%/°C to 1.43 wt.%/°C. Analytical Py-GC/MS revealed that potassium had a distinguished catalytic effect promoting the formation of low molecular weight compounds and suppressing the formation of levoglucosan. An increase in the yield of C6 and C2C6 lignin derivatives with increasing potassium content was also observed.


Assuntos
Calefação/métodos , Lignina/química , Lignina/efeitos da radiação , Metais/química , Metais/efeitos da radiação , Madeira/química , Madeira/efeitos da radiação , Biodegradação Ambiental
7.
Bioresour Technol ; 102(19): 9020-5, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21840709

RESUMO

1-Ethyl-3-methylimidazolium acetate ([Emim][CH3COO]) was used for the extraction of lignin from poplar wood (Populus albaglandulosa), which was called to ionic liquid lignin (ILL) and structural features of ILL were compared with the corresponding milled wood lignin (MWL). Yields of ILL and MWL were 5.8±0.3% and 4.4±0.4%, respectively. The maximum decomposition rate (V(M)) and temperature (T(M)) corresponding to V(M) were 0.25%/ °C and 308.2 °C for ILL and 0.30%/ °C and 381.3 °C for MWL. The amounts of functional groups (OMe and phenolic OH) appeared to be similar for both lignins; approximately 15.5% and 6.7% for ILL and 14.4% and 6.3% for MWL. However, the weight average molecular weight (M(w)) of ILL (6347 Da) was determined to be 2/3-fold of that of MWL (10,002 Da) and polydispersity index (PDI: M(w)/M(n)) suggested that the lignin fragments were more uniform in the ILL (PDI 1.62) than in the MWL (PDI 2.64).


Assuntos
Líquidos Iônicos/química , Lignina/química , Populus/química , Cromatografia em Gel , Imidazóis , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Termogravimetria
8.
J Biosci Bioeng ; 106(2): 162-7, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18804059

RESUMO

Enzymatic saccharification of lignocellulosic biomass was performed using culture filtrates of brown rot fungi including Gloeophyllum sepiarium, Fomitopsis pinicola, and Laetiporus sulphureus. Biological treatment with white rot fungi was used as pretreatment prior to enzymatic saccharification. Endoglucanase, beta-glucosidase, xylanase and cellobiohydrolase activities were determined from concentrated culture filtrates of the brown rot fungi. L. sulphureus has the highest endoglucanase, beta-glucosidase, and xylanase activities, and F. pinicola has the highest cellobiohydrolase activity. When enzymes from L. sulphureus were used along with the lignocellulosic biomass pretreated with Stereum hirsutum as the carbon source, the total sugar yield was 11.36 mg/0.25 g of dry weight biomass, with the highest activities of cellulase and hemicellulase. In order to increase the sugar yield, the enzymes from L. sulphureus were mixed with those from F. pinicola, which showed high cellobiohydrolase activity. This caused an increase in the sugar yield from 11.36 mg to 15.22 mg. When temperature was increased to 50 degrees C, the total sugar yield increased to 17.74 mg for the same reaction time. The crystallinity of lignocellulosic biomass decreased from 68.4% to 60.2%, when lignocellulosic biomass pretreated with S. hirsutum was hydrolyzed using enzymes from L. sulphureus.


Assuntos
Metabolismo dos Carboidratos , Coriolaceae/enzimologia , Enzimas/metabolismo , Pinus/metabolismo , Biomassa , Cristalografia por Raios X , Meios de Cultura
9.
Bioresour Technol ; 99(8): 2736-41, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-17698351

RESUMO

In order to investigate the possibility of using waste mushroom logs as a biomass resource for alternative energy production, the chemical and physical characteristics of normal wood and waste mushroom logs were examined. Size reduction of normal wood (145 kW h/tone) required significantly higher energy consumption than waste mushroom logs (70 kW h/tone). The crystallinity value of waste mushroom logs was dramatically lower (33%) than normal wood (49%) after cultivation by Lentinus edodes as spawn. Lignin, an enzymatic hydrolysis inhibitor in sugar production, decreased from 21.07% to 18.78% after inoculation of L. edodes. Total sugar yields obtained by enzyme and acid hydrolysis were higher in waste mushroom logs than in normal wood. After 24h fermentation, 12 g/L ethanol was produced on waste mushroom logs, while normal wood produced 8 g/L ethanol. These results indicate that waste mushroom logs are economically suitable lignocellulosic material for the production of fermentable sugars related to bioethanol production.


Assuntos
Agaricales/crescimento & desenvolvimento , Biomassa , Etanol/metabolismo , Lentinula/crescimento & desenvolvimento , Eliminação de Resíduos de Serviços de Saúde/métodos , Agaricales/metabolismo , Metabolismo Energético , Fermentação , Hidrólise , Lignina/metabolismo , Nitrobenzenos , Oxirredução , Madeira , Difração de Raios X
10.
J Microbiol Biotechnol ; 17(11): 1811-7, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18092465

RESUMO

Extracellular enzymes from Lentinus edodes M290 on normal woods (Quercus mongolica) and waste logs from oak mushroom production were comparatively investigated. Endoglucanase, cellobiohydrolase, beta-glucosidase, and xylanase activities were higher on waste mushroom logs than on normal woods after L. edodes M290 inoculation. Xylanase activity was especially different, with a three times higher activity on waste mushroom logs. When the waste mushroom logs were used as a carbon source, a new 35 kDa protein appeared. After the purification, the optimal pH and temperature for xylanase activity were determined to be 4.0 and 50 degrees C, respectively. More than 50% of the optimal xylanase activity was retained when the temperature was increased from 20 to 60 degrees C, after a 240 min reaction. At 40 degrees C, the xylanase maintained 93% of the optimal activity, after a 240 min reaction. The purified xylanase showed a very high homology to the xylanase family 10 from Aspergillus terreus by LC/MS-MS analysis. The highest Xcorr (1.737) was obtained from the peptide KWI SQGIPIDGIG SQTHLGSGGS WTVK originated from Aspergillus terreus, indicating that the 35 kDa protein was xylanase. This protein showed low homology to a previously reported L. edodes xylanase sequence.


Assuntos
Endo-1,4-beta-Xilanases/metabolismo , Cogumelos Shiitake/enzimologia , Agaricales , Sequência de Aminoácidos , Biomassa , Endo-1,4-beta-Xilanases/química , Endo-1,4-beta-Xilanases/isolamento & purificação , Concentração de Íons de Hidrogênio , Dados de Sequência Molecular , Cogumelos Shiitake/crescimento & desenvolvimento , Temperatura
11.
Biofactors ; 29(2-3): 67-75, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17673824

RESUMO

Previously we reported that cadalene extracted from Zelkova serrata inhibited lung tumorigenesis in mice. However, the precise mechanism has not yet investigated. Here, we examined the effects of cadalene on signal pathways important for apoptosis, cell cycle, and protein translation in lung cancer cells. Our results showed that cadalene suppressed the expression of Akt and its phosphor-forms through controlling PI3K and PTEN. Cadalene also induced apoptosis through facilitating pro-apoptotic protein expression. In addition, cadalene caused cell cycle arrest and decreased mTOR-mediated protein translation. Taken together, cadalene may be developed as a lung cancer therapeutic agent in the future.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Sesquiterpenos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Neoplasias Pulmonares/patologia , PTEN Fosfo-Hidrolase/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Sesquiterpenos Policíclicos , Biossíntese de Proteínas/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/biossíntese , Transdução de Sinais/efeitos dos fármacos
12.
Biotechnol Bioeng ; 97(6): 1516-22, 2007 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-17221890

RESUMO

In this study, white rot fungus, Polyporus brumalis, was applied to degrade dibutyl phthalate (DBP), a major environmental pollutant. The degradation potential and resulting products were evaluated with HPLC and GC/MS. As DBP concentration increased to 250, 750, and 1,250 microM, the mycelial growth of P. brumalis was inhibited. However, growth was still observed in the 1,250 microM concentration. DBP was nearly eliminated from culture medium of P. brumalis within 12 days, with 50% of DBP adsorbed by the mycelium. Diethyl phthalate (DEP) and monobutyl phthalate (MBP) were detected as intermediate degradation products of DBP. In culture medium, the concentration of DEP was higher than that of MBP during the incubation period. After 12-15 days, the concentrations of both decreased rapidly in the culture medium. The primary final degradation product of DBP in culture medium was phthalic acid anhydride, as well as trace amounts of aromatic compounds, such as alpha-hydroxyphenylacetic acid, benzyl alcohol, and O-hydroxyphenylacetic acid. According to these results, the degradation of DBP in culture medium by the white rot fungus, P. brumalis, may be completed through two pathways-transesterification and de-esterification-which successively combine into an intracellular degradation pathway.


Assuntos
Basidiomycota/crescimento & desenvolvimento , Basidiomycota/metabolismo , Dibutilftalato/metabolismo , Biodegradação Ambiental
13.
J Microbiol ; 45(6): 485-91, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18176529

RESUMO

The effects of biological pretreatment on the Japanese red pine Pinus densiflora, was evaluated after exposure to three white rot fungi Ceriporia lacerata, Stereum hirsutum, and Polyporus brumalis. Change in chemical composition, structural modification, and their susceptibility to enzymatic saccharification in the degraded wood were analyzed. Of the three white rot fungi tested, S. hirsutum selectively degraded the lignin of this sortwood rather than the holocellulose component. After eight weeks of pretreatment with S. hirsutum, total weight loss was 10.7%, while lignin loss was the highest at 14.52% among the tested samples. However, holocellulose loss was lower at 7.81% compared to those of C. lacerata and P. brumalis. Extracelluar enzymes from S. hirsutum showed higher activity of ligninase and lower activity of cellulase than those from other white rot fungi. Thus, total weight loss and changes in chemical composition of the Japanese red pine was well correlated with the enzyme activities related with lignin- and cellulose degradation in these fungi. Based on the data obtained from analysis of physical characterization of degraded wood by X-ray Diffractometry (XRD) and pore size distribution, S. hirsutum was considered as an effective potential fungus for biological pretreatment. In particular, the increase of available pore size of over 120 nm in pretreated wood powder with S. hirsutum made enzymes accessible for further enzymatic saccharification. When Japanese red pine chips treated with S. hirsutum were enzymatically saccharified using commercial enzymes (Cellulclast 1.5 L and Novozyme 188), sugar yield was greatly increased (21.01%) compared to non-pretreated control samples, indicating that white rot fungus S. hirsutum provides an effective process in increasing sugar yield from woody biomass.


Assuntos
Basidiomycota/metabolismo , Pinus/metabolismo , Basidiomycota/crescimento & desenvolvimento , Biodegradação Ambiental , Biomassa , Celulase/metabolismo , Celulose/química , Celulose/metabolismo , Lignina/química , Lignina/metabolismo , Oxigenases/metabolismo , Pinus/química , Difração de Raios X
14.
Arch Pharm Res ; 29(12): 1114-8, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17225460

RESUMO

(+)-Eudesmin [4,8-bis(3,4-dimethoxyphenyl)-3,7-dioxabicyclo[3.3.0]octane] was isolated from the stem bark of Magnolia kobus DC. var. borealis Sarg. and found to have neuritogenic activity. 50 microM (+)-eudesmin induced neurite outgrowth and enhanced nerve growth factor (NGF)-mediated neurite outgrowth from PC12 cells. At this concentration, (+)-eudesmin also enhanced NGF-induced neurite-bearing activity and this activity was partially blocked by various protein kinase inhibitors. These included PD98059, a mitogen-activated protein kinase (MAPK) kinase inhibitor. GF109203X, a protein kinase C (PKC) inhibitor and H89, a protein kinase A (PKA) inhibitor. These results suggest that (+)-eudesmin can induce neurite outgrowth from PC12 cells by stimulating up-stream MAPK, PKC and PKA pathways.


Assuntos
Furanos/farmacologia , Lignanas/farmacologia , Magnolia/química , Neuritos/efeitos dos fármacos , Casca de Planta/química , Animais , Flavonoides/farmacologia , Furanos/antagonistas & inibidores , Furanos/isolamento & purificação , Humanos , Indóis/farmacologia , Isoquinolinas/farmacologia , Lignanas/antagonistas & inibidores , Lignanas/isolamento & purificação , Espectroscopia de Ressonância Magnética , Maleimidas/farmacologia , Células PC12 , Inibidores de Proteínas Quinases/farmacologia , Ratos , Sulfonamidas/farmacologia
15.
Biol Pharm Bull ; 28(2): 201-7, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15684469

RESUMO

Two lignin-degrading basidiomycetes, Stereum hirsutum and Heterobasidium insulare, were used to degrade bisphenol A (BPA) in culture, and the estrogenic activity of the degradation products was examined using MCF-7 cell proliferation assays (E-screen) and analysis of pS2 mRNA expression in MCF 7 cells. Both S. hirsutum and H. insulare showed high resistance to BPA 100 ppm, and their mycelial growth was fully completed within 8 d of incubation at 30 degrees C. It took 7 to 14 d to achieve complete degradation (ca. 99%) of BPA by both fungi. MCF-7 cells proliferated actively at a BPA concentration of 10(-5) M. However, cell line proliferation was significantly inhibited when the cells were incubated in BPA culture media containing S. hirsutum and H. insulare. Similar results were obtained regarding pS2 mRNA expression. The pS2 mRNA expression levels decreased by 1.5-fold in supernatant from BPA treated with S. hirsutum and H. insulare compared with those treated with BPA alone.


Assuntos
Basidiomycota/metabolismo , Estrogênios não Esteroides/metabolismo , Fenóis/metabolismo , Compostos Benzidrílicos , Linhagem Celular , Estrogênios não Esteroides/análise , Humanos , Fenóis/análise
16.
J Agric Food Chem ; 51(17): 4884-8, 2003 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-12903940

RESUMO

The toxicity of Eugenia caryophyllata bud and leaf oil-derived compounds (acetyleugenol, beta-caryophyllene, eugenol, alpha-humulene, and methyl salicylate) and congeners of eugenol (isoeugenol and methyleugenol) against eggs and females of Pediculus capitis was examined using direct contact application and fumigation methods and compared with those of the widely used delta-phenothrin and pyrethrum. In a filter paper diffusion bioassay with female P. capitis, the pediculicidal activity of the Eugenia bud and leaf oils was comparable to those of delta-phenothrin and pyrethrum on the basis of LT(50) values at 0.25 mg/cm(2). At 0.25 mg/cm(2), the compound most toxic to female P. capitis was eugenol followed by methyl salicylate. Acetyleugenol, beta-caryophyllene, alpha-humulene, isoeugenol, and methyleugenol were not effective. Eugenol at 0.25 mg/cm(2) was as potent as delta-phenothrin and pyrethrum but was slightly less effective than the pyrethroids at 0.125 mg/cm(2). Against P. capitis eggs, methyl salicylate and eugenol were highly effective at 0.25 and 1.0 mg/cm(2), respectively, whereas little or no activity at 5 mg/cm(2) was observed with the other test compounds as well as with delta-phenothrin and pyrethrum. In fumigation tests with female P. capitis at 0.25 mg/cm(2), eugenol and methyl salicylate were more effective in closed cups than in open ones, indicating that the effect of the compounds was largely due to action in the vapor phase. Neither delta-phenothrin nor pyrethrum exhibited fumigant toxicity. The Eugenia bud and leaf essential oils, particularly eugenol and methyl salicylate, merit further study as potential P. capitis control agents or lead compounds.


Assuntos
Inseticidas/análise , Pediculus , Folhas de Planta/química , Óleos de Plantas/química , Estruturas Vegetais/química , Syzygium/química , Animais , Eugenol/análise , Feminino , Salicilatos/análise
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