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1.
Molecules ; 26(15)2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34361724

RESUMO

Orchids are rich treasure troves of various important phytomolecules. Among the various medicinal orchids, Ansellia africana stands out prominently in the preparing of various herbal medicines due to its high therapeutic importance. The nodal explants of A. africana were sampled from asymbiotically germinated seedlings on basal Murashige and Skoog (MS) medium and were micropropagated in MS medium supplemented with 3% sucrose and 10 µM meta topolin (mT) + 5 µM naphthalene acetic acid (NAA) +15 µM indole butyric acid (IBA) + 30 µM phloroglucinol (PG). In the present study, the essential oil was extracted by hydrodistillation and the oleoresins by the solvent extraction method from the micropropagated A. africana. The essential oil and the oleoresins were analysed by Gas Chromatography (GC) and GC/MS (Mass spectrometry). A total of 84 compounds were identified. The most predominant components among them were linoleic acid (18.42%), l-ascorbyl 2,6-dipalmitate (11.50%), linolenic acid (10.98%) and p-cresol (9.99%) in the essential oil; and eicosane (26.34%), n-butyl acetate (21.13%), heptadecane (16.48%) and 2-pentanone, 4-hydroxy-4-methyl (11.13%) were detected in the acetone extract; heptadecane (9.40%), heneicosane (9.45%), eicosane (6.40%), n-butyl acetate (14.34%) and styrene (22.20%) were identified and quantified in the ethyl acetate extract. The cytotoxic activity of essential oil and oleoresins of micropropagated A. africana was evaluated by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium Bromide) assay on Vero cells compared to the standard drug doxorubicin chloride. The present research contains primary information about the therapeutic utility of the essential oil and oleoresins of A. africana with a promising future research potential of qualitative and quantitative improvement through synchronised use of biotechnological techniques.


Assuntos
Citotoxinas/isolamento & purificação , Óleos Voláteis/isolamento & purificação , Orchidaceae/química , Extratos Vegetais/isolamento & purificação , Plântula/química , Acrilatos/isolamento & purificação , Alcanos/isolamento & purificação , Animais , Ácido Ascórbico/isolamento & purificação , Sobrevivência Celular/efeitos dos fármacos , Chlorocebus aethiops , Cresóis/isolamento & purificação , Meios de Cultura/química , Meios de Cultura/farmacologia , Citotoxinas/farmacologia , Cromatografia Gasosa-Espectrometria de Massas , Hidroponia/métodos , Ácido Linoleico/isolamento & purificação , Extração Líquido-Líquido/métodos , Óleos Voláteis/farmacologia , Orchidaceae/metabolismo , Palmitatos/isolamento & purificação , Pentanóis/isolamento & purificação , Pentanonas/isolamento & purificação , Extratos Vegetais/farmacologia , Plantas Medicinais , Plântula/metabolismo , África do Sul , Estireno/isolamento & purificação , Células Vero , Ácido alfa-Linolênico/isolamento & purificação
2.
World J Microbiol Biotechnol ; 36(11): 171, 2020 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-33067644

RESUMO

Aureobasidium strains isolated from diverse unconventional environments belonging to the species A. pullulans, A. melanogenum, and A. subglaciale were evaluated for Volatile Organic Compounds (VOCs) production as a part of their modes of action against Botrytis cinerea of tomato and table grape. By in vitro assay, VOCs generated by the antagonists belonging to the species A. subglaciale showed the highest inhibition percentage of the pathogen mycelial growth (65.4%). In vivo tests were conducted with tomatoes and grapes artificially inoculated with B. cinerea conidial suspension, and exposed to VOCs emitted by the most efficient antagonists of each species (AP1, AM10, AS14) showing that VOCs of AP1 (A. pullulans) reduced the incidence by 67%, partially confirmed by the in vitro results. Conversely, on table grape, VOCs produced by all the strains did not control the fungal incidence but were only reducing the infection severity (< 44.4% by A. pullulans; < 30.5% by A. melanogenum, and A. subglaciale). Solid-phase microextraction (SPME) and subsequent gas chromatography coupled to mass spectrometry identified ethanol, 3-methyl-1-butanol, 2-methyl-1-propanol as the most produced VOCs. However, there were differences in the amounts of produced VOCs as well as in their repertoire. The EC50 values of VOCs for reduction of mycelial growth of B. cinerea uncovered 3-methyl-1-butanol as the most effective compound. The study demonstrated that the production and the efficacy of VOCs by Aureobasidium could be directly related to the specific species and pathosystem and uncovers new possibilities for searching more efficient VOCs producing strains in unconventional habitats other than plants.


Assuntos
Aureobasidium/química , Botrytis/efeitos dos fármacos , Solanum lycopersicum/crescimento & desenvolvimento , Vitis/crescimento & desenvolvimento , Compostos Orgânicos Voláteis/farmacologia , Butanóis/isolamento & purificação , Butanóis/farmacologia , Cromatografia Gasosa-Espectrometria de Massas , Solanum lycopersicum/microbiologia , Testes de Sensibilidade Microbiana , Micélio/efeitos dos fármacos , Pentanóis/isolamento & purificação , Pentanóis/farmacologia , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle , Microextração em Fase Sólida , Vitis/microbiologia , Compostos Orgânicos Voláteis/isolamento & purificação
3.
Food Chem ; 329: 127175, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32516708

RESUMO

This report describes the development of a methodology based on micellar electrokinetic chromatography for the separation of alcohols on chip-based systems aiming the determination of alcoholic content in whiskey samples. The separation conditions were optimized the best results were achieved using 50 mmolL-1 phosphate buffer containing 30 mmolL-1 sodium dodecyl sulfate. The alcoholic content was determined in 16 seized whiskey samples from 4 different brands as well as in the original samples. The methodology presented herein allowed the correct classification of 75% of the seized samples as adulterated and the data obtained did not statistically differ from those recorded by a reference technique. The proposed analytical approach emerges as a promising tool to provide a rapid screening of the beverages authenticity and it may be useful to be widely explored for the quality control.


Assuntos
Bebidas Alcoólicas/análise , Cromatografia Capilar Eletrocinética Micelar/métodos , Análise de Alimentos/métodos , Soluções Tampão , Butanóis/isolamento & purificação , Cromatografia Capilar Eletrocinética Micelar/instrumentação , Etanol/isolamento & purificação , Qualidade dos Alimentos , Pentanóis/isolamento & purificação , Dodecilsulfato de Sódio
4.
Biosci Biotechnol Biochem ; 84(7): 1339-1344, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32290758

RESUMO

Catathelasmols C, D, and E, which had been isolated from Catathelasma imperiale as inhibitors for 11-hydroxysteroid dehydrogenases, were comprehensively semisynthesized from commercially available D-glutamic acid. The key synthetic intermediate, (R)-pentane-1,2,5-triol, was site-selectively acetylated by treatment with vinyl acetate and Candida antarctica lipase B (Novozym 435) in tetrahydrofuran (THF) at 25°C to furnish 1,5-diacetate (catathelasmol E, quantitative). The acetylation occurred site-selectively on the primary alcohols at the C-1 and C-5 positions over the secondary alcohol at the C-2 position. Dichromic acid oxidation provided 2-oxopentane-1,5-diyl diacetate (catathelasmol C, 78%). Burkholderia cepacia lipase-catalyzed transesterification with methanol in THF at - 5°C proceeded preferentially on the acetate at C-1 located adjacent to the C-2 carbonyl group over the other terminal acetate at the C-5 position. 5-Hydroxy-4-oxopentyl acetate (catathelasmol D) was obtained in 53% yield.


Assuntos
11-beta-Hidroxiesteroide Desidrogenases/antagonistas & inibidores , Agaricales/química , Domínio Catalítico , Ácido Glutâmico/metabolismo , Lipase/metabolismo , Pentanóis/síntese química , Acetatos/metabolismo , Acetilação , Burkholderia cepacia/enzimologia , Catálise , Proteínas Fúngicas/metabolismo , Furanos/metabolismo , Metanol/metabolismo , Pentanóis/isolamento & purificação , Metabolismo Secundário
5.
Food Chem ; 255: 282-289, 2018 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-29571478

RESUMO

2-Mercapto-3-methyl-1-butanol (2M3MB) imparts an onion-like off-flavor to beer and is believed to result from the hot aeration of brewer's wort. However, little has been reported regarding the mechanism of formation of 2M3MB. This paper investigates the precursors of 2M3MB formed during the brewing process. Our study of a cysteine conjugate as a precursor showed its negligible contribution to the formation of 2M3MB. The 2M3MB precursor was found to be a volatile compound because 2M3MB was formed in the distillate of hop extract. The precursor was purified through distillation, column chromatography, and preparative gas chromatography, and the 2M3MB-producing potential was measured as an index for estimating the concentration of the precursor. The accurate mass of the precursor was measured using gas chromatography coupled to quadrupole-time-of-flight-mass spectrometry (GC/QTOF). The molecular structure was identified from the product ion spectra by GC/QTOF to be 2,3-epoxy-3-methylbutanal.


Assuntos
Aldeídos/química , Cerveja/análise , Aromatizantes/química , Odorantes/análise , Pentanóis/química , Cromatografia Gasosa-Espectrometria de Massas , Cebolas/química , Pentanóis/isolamento & purificação , Pró-Fármacos/química , Paladar
6.
Cell Mol Biol (Noisy-le-grand) ; 63(2): 112-121, 2017 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-28364792

RESUMO

The rapid diagnosis of respiratory infections has always been an important goal for medical professionals, because rapid and accurate diagnosis leads to proper and timely treatment, and consequently, reduces the costs of incorrect and long-term treatments, and antibiotic resistance. The present study was conducted with the aim of detecting volatile organic compounds (VOCs) in three bacteria: Pseudomonas aeruginosa, Acinetobacter baumannii, Klebsiella pneumoniae. Headspace of the studied bacteria, after separately culturing in two types of liquid medium in three different time-periods, was extracted by solid phase microextraction and analysed by gas chromatography mass spectrometry The analysis results of the VOCs produced by the studied bacteria indicate that some VOCs are common and some are unique in each bacterium. 1-penten-3-ol, levomenthol, and 2-octyl-1-ol for P. aeruginosa, cyclohexene, 4-ethenyl, and cis-Dihydro-α-terpinyl acetate for A. baumannii and 1,3-butadiene, butyraldehyde, longifolene, octyl acetate, tridecanol, dodecenal, (E)-2-hexyl ester, butanoic acid, and 5,5-dodecadinyl-1 12-diol for K. pneumoniae were identified as unique VOCs for each bacterium. Finally, it can be said that an accurate and rapid bacterial detection method can be achieved by using a tool that can detect bacterial VOCs. However, more studies are needed to design a tool for which all aspects have been assessed, so that it can give us a more complete pattern for the use of these compounds as biomarkers.


Assuntos
Acinetobacter baumannii/química , Klebsiella pneumoniae/química , Pseudomonas aeruginosa/química , Compostos Orgânicos Voláteis/análise , Acetatos/análise , Acetatos/isolamento & purificação , Aldeídos/análise , Aldeídos/isolamento & purificação , Infecções Bacterianas/microbiologia , Butadienos/análise , Butadienos/isolamento & purificação , Ácido Butírico/análise , Ácido Butírico/isolamento & purificação , Cicloexenos/análise , Cicloexenos/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Pentanóis/análise , Pentanóis/isolamento & purificação , Sistema Respiratório/microbiologia , Sesquiterpenos/análise , Sesquiterpenos/isolamento & purificação , Microextração em Fase Sólida , Especificidade da Espécie , Compostos Orgânicos Voláteis/isolamento & purificação
7.
J Biotechnol ; 238: 60-68, 2016 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-27671695

RESUMO

Lipases are important catalysts in chiral synthesis due to their wide substrate recognition combined with a high stereoselectivity. We demonstrate here that the state, free or immobilized, of Candida antarctica lipase B (CaLB) affects enantioselectivity and also alters the temperature dependancy of the enzyme. This indicates that CaLB undergoes various conformations induced by its interaction with the different immobilization supports studied. Molecular imprinting experiments, using immobilized enzyme co-dried with mimic substrate molecules, enhanced the enantiomeric ratio two-fold or three-fold, depending on the immobilization support. The structure of the acyl donor has a pronounced effect on CaLB catalyzed resolution, due to the proximity of the acyl and alcohol moieties during catalysis. When the acylation of pentan-2-ol was examined, we found that the 3C methyl propanoate donor afforded the highest resolution. Trans-(Z)-cyclooct-5-en-1,2-diol was used as a model racemic substrate to study the ability of lipase to catalyze the resolution of difunctionalized compounds. There was a clear enhancement in the enantiomer selectivity of the biotransformation of the diol when vinyl butanoate is used as the acyl donor. The conversion and enantiomeric excess of (1R,2R)-monoacetates were enhanced, using immobilized CaLB, when the chain length of the donors increased from C2 to C4.


Assuntos
Reatores Biológicos , Ciclo-Octanos/química , Enzimas Imobilizadas/metabolismo , Proteínas Fúngicas/metabolismo , Lipase/metabolismo , Pentanóis/química , Ciclo-Octanos/isolamento & purificação , Ciclo-Octanos/metabolismo , Nitrogênio , Pentanóis/isolamento & purificação , Pentanóis/metabolismo , Temperatura
8.
J Lipid Res ; 57(6): 1051-8, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27127078

RESUMO

Acne is a multifactorial skin disorder frequently observed during adolescence with different grades of severity. Multiple factors centering on sebum secretion are implicated in acne pathogenesis. Despite the recognized role of sebum, its compositional complexity and limited analytical approaches have hampered investigation of alterations specifically associated with acne. To examine the profiles of lipid distribution in acne sebum, 61 adolescents (29 males and 32 females) were enrolled in this study. Seventeen subjects presented no apparent clinical signs of acne. The 44 affected individuals were clinically classified as mild (13 individuals), moderate (19 individuals), and severe (12 individuals) acne. Sebum was sampled from the forehead with Sebutape(TM) adhesive patches. Profiles of neutral lipids were acquired with rapid-resolution reversed-phase/HPLC-TOF/MS in positive ion mode. Univariate and multivariate statistical analyses led to the identification of lipid species with significantly different levels between healthy and acne sebum. The majority of differentiating lipid species were diacylglycerols (DGs), followed by fatty acyls, sterols, and prenols. Overall, the data indicated an association between the clinical grading of acne and sebaceous lipid fingerprints and highlighted DGs as more abundant in sebum from adolescents affected with acne.


Assuntos
Acne Vulgar/metabolismo , Diglicerídeos/isolamento & purificação , Lipídeos/isolamento & purificação , Pele/metabolismo , Esteróis/isolamento & purificação , Acne Vulgar/patologia , Adolescente , Adulto , Cromatografia Líquida de Alta Pressão , Diglicerídeos/metabolismo , Feminino , Hemiterpenos , Humanos , Lipídeos/química , Lipídeos/classificação , Masculino , Pentanóis/química , Pentanóis/isolamento & purificação , Sebo/metabolismo , Índice de Gravidade de Doença , Pele/química , Pele/patologia , Esteróis/metabolismo
9.
Metab Eng ; 34: 25-35, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26708516

RESUMO

Branched C5 alcohols are promising biofuels with favorable combustion properties. A mevalonate (MVA)-based isoprenoid biosynthetic pathway for C5 alcohols was constructed in Escherichia coli using genes from several organisms, and the pathway was optimized to achieve over 50% theoretical yield. Although the MVA pathway is energetically less efficient than the native methylerythritol 4-phosphate (MEP) pathway, implementing the MVA pathway in bacterial hosts such as E. coli is advantageous due to its lack of endogenous regulation. The MVA and MEP pathways intersect at isopentenyl diphosphate (IPP), the direct precursor to isoprenoid-derived C5 alcohols and initial precursor to longer chain terpenes, which makes independent regulation of the pathways difficult. In pursuit of the complete "decoupling" of the MVA pathway from native cellular regulation, we designed novel IPP-bypass MVA pathways for C5 alcohol production by utilizing promiscuous activities of two enzymes, phosphomevalonate decarboxylase (PMD) and an E. coli-endogenous phosphatase (AphA). These bypass pathways have reduced energetic requirements, are further decoupled from intrinsic regulation, and are free from IPP-related toxicity. In addition to these benefits, we demonstrate that reduced aeration rate has less impact on the bypass pathway than the original MVA pathway. Finally, we showed that performance of the bypass pathway was primarily determined by the activity of PMD. We designed PMD mutants with improved activity and demonstrated titer increases in the mutant strains. These modified pathways would be a good platform for industrial production of isopentenol and related chemicals such as isoprene.


Assuntos
Escherichia coli/metabolismo , Hemiterpenos/metabolismo , Engenharia Metabólica/métodos , Redes e Vias Metabólicas/fisiologia , Ácido Mevalônico/metabolismo , Compostos Organofosforados/metabolismo , Pentanóis/metabolismo , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Análise do Fluxo Metabólico , Metaboloma/fisiologia , Pentanóis/isolamento & purificação , Transdução de Sinais/fisiologia
10.
Talanta ; 116: 866-9, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-24148486

RESUMO

We analyzed 21 neat acetone samples from 15 different suppliers to demonstrate the utility of a coupled stable isotope and trace contaminant strategy for distinguishing forensically-relevant samples. By combining these two pieces of orthogonal data we could discriminate all of the acetones that were produced by the 15 different suppliers. Using stable isotope ratios alone, we were able to distinguish 8 acetone samples, while the remaining 13 fell into four clusters with highly similar signatures. Adding trace chemical contaminant information enhanced discrimination to 13 individual acetones with three residual clusters. The acetones within each cluster shared a common manufacturer and might, therefore, not be expected to be resolved. The data presented here demonstrates the power of combining orthogonal data sets to enhance sample fingerprinting and highlights the role disparate data could play in future forensic investigations.


Assuntos
Acetona/isolamento & purificação , Ciências Forenses/métodos , Espectrometria de Massas/estatística & dados numéricos , Acetona/classificação , Isótopos de Carbono , Terrorismo Químico/prevenção & controle , Deutério , Análise Discriminante , Ciências Forenses/instrumentação , Hexanonas/isolamento & purificação , Humanos , Cetonas/isolamento & purificação , Pentanóis/isolamento & purificação , Pentanonas/isolamento & purificação
11.
Sensors (Basel) ; 13(3): 2818-29, 2013 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-23447013

RESUMO

Static headspace gas chromatographic (SHS-GC) analysis was performed to determine the release of 13 odorants in hydrocolloid model systems containing original or regio-selectively carboxylated cellulose at different pH values. The release of most odor compounds was decreased in the hydrocolloid solutions compared to control, with the amounts of 2-propanol, 3-methyl-1-butanol, and 2,3-butanedione released into the headspace being less than those of any other odor compound in the hydrocolloid model systems. However, there was no considerable difference between original cellulose-containing and carboxylated-cellulose containing systems in the release of most compounds, except for relatively long-chain esters such as ethyl caprylate and ethyl nonanoate. The release from the original and carboxylated cellulose solutions controlled to pH 10 was significantly higher than that from solutions adjusted to pH 4 and 7 in the case of some esters (ethyl acetate, methyl propionate, ethyl propionate, ethyl butyrate, butyl propionate, ethyl caproate) and alcohols (2-propanol, 3-methyl-1-butanol), in particular, ethyl butyrate and 3-methyl-1-butanol. In contrast, the release of 2,3-butanedione from both the original and carboxylated cellulose solutions was increased at pH 4 and 7 compared to that at pH 10 by about 70% and 130%, respectively. Our study demonstrated that the release of some odorants could be changed significantly by addition of both original and carboxylated cellulose in hydrocolloid model systems, but only minor effect was observed in pH of the solution.


Assuntos
Celulose/química , Coloides/química , Odorantes/análise , 2-Propanol/análise , 2-Propanol/isolamento & purificação , Ácidos Carboxílicos/química , Cromatografia Gasosa , Diacetil/isolamento & purificação , Ésteres/isolamento & purificação , Concentração de Íons de Hidrogênio , Pentanóis/isolamento & purificação
12.
Molecules ; 18(2): 2166-82, 2013 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-23434869

RESUMO

Polyprenols separated from lipids are promising new components from Ginkgo biloba L. leaves (GBL). In this paper, ginkgo lipids were isolated by extraction with petroleum ether, saponification, and molecular distillation. Eight known compounds: isophytol (1), nerolidol (2), linalool (3), ß-sitosterol acetate (4), ß-sitosterol (5), stigmasterol (6), ergosterol (7), ß-sitosterol-3-O-ß-D-glucopyranoside (8) and Ginkgo biloba polyprenols (GBP) were separated from GBL by chromatography and identified mainly by NMR. The separated and identified compounds 1, 2 and 3 are reported here for the first time in GBL. The 3D-DAD-HPLC-chromatogram (190-232 nm) of GBP was recorded. This study provides new evidence as there are no previous reports on antibacterial/antifungal activities and synergistic interactions between GBP and the compounds separated from GBL lipids against Salmonella enterica, Staphylocococus aureus and Aspergillus niger. Nerolidol (2) showed the highest activity among all the tested samples and of all mixture groups tested the GBP with isophytol (1) mixture had the strongest synergistic effect against Salmonella enterica among the three tested strains. A proportion of isophytol and GBP of 38.19%:61.81% (wt/wt) was determined by mixture design as the optimal proportion for the synergistic effect of GBP with isophytol against Salmonella enterica.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Ginkgo biloba/química , Lipídeos/isolamento & purificação , Pentanóis/farmacologia , Folhas de Planta/química , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antifúngicos/química , Antifúngicos/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Sinergismo Farmacológico , Hemiterpenos , Lipídeos/química , Testes de Sensibilidade Microbiana , Pentanóis/química , Pentanóis/isolamento & purificação , Fitol/análogos & derivados , Fitol/farmacologia , Salmonella enterica/efeitos dos fármacos
13.
J Am Chem Soc ; 134(20): 8703-10, 2012 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-22545712

RESUMO

Four porous isostructural mixed-metal-organic frameworks (M'MOFs) have been synthesized and structurally characterized. The pores within these M'MOFs are systematically tuned by the interplay of both the metalloligands and organic ligands which have enabled us not only to direct their highly selective separation of chiral alcohols 1-phenylethanol (PEA), 2-butanol (BUT), and 2-pentanol (2-PEN) with the highest ee up to 82.4% but also to lead highly selective separation of achiral C(2)H(2)/C(2)H(4) separation. The potential application of these M'MOFs for the fixed bed pressure swing adsorption (PSA) separation of C(2)H(2)/C(2)H(4) has been further examined and compared by the transient breakthrough simulations in which the purity requirement of 40 ppm in the outlet gas can be readily fulfilled by the fixed bed M'MOF-4a adsorber at ambient conditions.


Assuntos
Álcoois Benzílicos/isolamento & purificação , Butanóis/isolamento & purificação , Compostos Organometálicos/química , Pentanóis/isolamento & purificação , Adsorção , Cristalografia por Raios X , Ligantes , Modelos Moleculares , Compostos Organometálicos/síntese química , Porosidade , Estereoisomerismo
14.
Fitoterapia ; 82(6): 834-40, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21596107

RESUMO

The hepatoprotective effects of polyprenols from Ginkgo biloba L. leaves were evaluated against carbon tetrachloride induced hepatic damage in Sprague-Dawley rats. The elevated levels of serum ALT, AST, ALP, ALB, TP, HA, LN, TG, and CHO were restored towards normalization significantly by GBP in a dose dependent manner. The biochemical observations were supplemented with histopathological examination of rat liver sections. Meanwhile, GBP also produced a significant and dose-dependent reversal of CCl(4)-diminished activity of the antioxidant enzymes and reduced CCl(4)-elevated level of MDA. In general, the effects of GBP were not significantly different from those of the standard drug Essentiale.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Ginkgo biloba/química , Hepatopatias/prevenção & controle , Pentanóis/farmacologia , Extratos Vegetais/farmacologia , Animais , Antioxidantes/metabolismo , Tetracloreto de Carbono/toxicidade , Feminino , Hemiterpenos , Masculino , Pentanóis/química , Pentanóis/isolamento & purificação , Extratos Vegetais/química , Folhas de Planta/química , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley
15.
Bioresour Technol ; 99(17): 8016-21, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18445522

RESUMO

Biodegradation kinetic behaviors of ethyl acetate and amyl acetate in a composite bead biofilter were investigated. The composite bead was the spherical PVA/peat/KNO3/GAC composite bead which was prepared in our previous works. Both microbial growth rate and biochemical reaction rate were inhibited at higher inlet concentration. For the microbial growth process, the microbial growth rate of ethyl acetate was greater than that of amyl acetate in the inlet concentration range of 100-400ppm. The degree of inhibitive effect was almost the same for ethyl acetate and amyl acetate in this concentration range. The half-saturation constant Ks values of ethyl acetate and amyl acetate were 16.26 and 12.65ppm, respectively. The maximum reaction rate Vm values of ethyl acetate and amyl acetate were 4.08 and 3.53gCh(-1)kg(-1) packed material, respectively. Zero-order kinetic with the diffusion limitation could be regarded as the most adequate biochemical reaction model. For the biochemical reaction process, the biochemical reaction rate of ethyl acetate was greater than that of amyl acetate in the inlet concentration range of 100-400ppm. The inhibitive effect for ethyl acetate was more pronounced than that for AA in this concentration range. The maximum elimination capacity of ethyl acetate and amyl acetate were 82.3 and 37.93gCh(-1)m(-3) bed volume, respectively. Ethyl acetate degraded by microbial was easier than amyl acetate did.


Assuntos
Acetatos/isolamento & purificação , Filtração/instrumentação , Microesferas , Pentanóis/isolamento & purificação , Bactérias/crescimento & desenvolvimento , Biodegradação Ambiental , Cinética , Compostos Orgânicos , Fatores de Tempo , Volatilização
16.
Acta Biochim Pol ; 54(4): 727-32, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18066396

RESUMO

The occurrence of polyprenols in leaves of over 340 species of dendroflora in natural habitats in the regions of Hanoi and Hue in Vietnam was studied. Plant material was collected in the late autumn (October/November) during the end of a vegetation season. Leaves of about 200 plant species did not contain detectable amounts of polyprenols in contrast to few systematic families, e.g. Moraceae, Euphorbiaceae, where polyprenols were highly abundant and their pattern could be used as a chemotaxonomic criterion. Most often dominating polyprenols were prenol-11 and prenol-12. In several angiosperm species prenol-13 and detectable amounts of prenol-14 were also found. The incidence of prenol-13 and -14 was not restricted to a specific taxonomic group since species exhibiting domination of such longer chain polyprenols belonged to various systematic families. In some plants (e.g. Ceiba pentandra) alpha-cis polyprenols were accompanied by alpha-trans counterparts. This report describes several new plant species that may serve as natural sources of long chain polyprenols.


Assuntos
Pentanóis/isolamento & purificação , Folhas de Planta/química , Hemiterpenos , Vietnã
17.
J Chem Ecol ; 33(5): 935-45, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17393281

RESUMO

Workers of the slave-making ant, Polyergus breviceps, raid nests of Formica ants and return with Formica pupae that mature into worker ants in the slave-makers' colony. These Formica workers then tend the Polyergus brood, workers, and reproductives. During raids in the mating season, winged virgin Polyergus queens accompany the workers in the raiding columns. During the raid, the virgin queens release a pheromone that attracts males that quickly mate with the queens. We report the identification, synthesis, and bioassay of the sex attractant pheromone of the queens as an approximately 1:6 ratio of (R)-3-ethyl-4-methylpentan-1-ol and methyl 6-methylsalicylate. The ants produce exclusively the (R)-enantiomer of the alcohol, and the (S)-enantiomer has no biological activity, neither inhibiting nor increasing attraction to blends of methyl 6-methylsalicylate with the (R)-enantiomer.


Assuntos
Formigas/fisiologia , Pentanóis/isolamento & purificação , Salicilatos/isolamento & purificação , Atrativos Sexuais/isolamento & purificação , Animais , Feminino , Masculino , Pentanóis/síntese química , Pentanóis/farmacologia , Salicilatos/síntese química , Salicilatos/farmacologia , Atrativos Sexuais/síntese química , Atrativos Sexuais/farmacologia , Comportamento Sexual Animal/efeitos dos fármacos
18.
Comp Biochem Physiol B Biochem Mol Biol ; 139(2): 245-51, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15465671

RESUMO

The renal metabolism of the tripeptide, gamma-glutamylfelinylglycine, which our group recently identified in the blood of domestic cats (Felis catus), was investigated. To test our hypothesis that this unique tripeptide is metabolised by the kidney in a similar manner to glutathione-S-conjugates in other animal species, [(35)S]cysteine was administered intraperitoneally to an entire male cat, and urine collected at 1, 4 and 8 h post-injection. Radiolabelled fractions were isolated from the urine following reversed-phase (RP) HPLC. Four [(35)S]radiolabelled fractions were identified and characterised by amino acid analysis, mass spectrometry and comparison of retention times with synthetic compounds (felinine, N-acetyl felinine, felinylglycine, gamma-glutamylfelinylglycine). In addition to the previously described presence of free felinine, we showed the presence of several felinine-containing metabolites, including N-acetyl felinine, felinylglycine and unaltered gamma-glutamylfelinylglycine in cat urine. The results show that renal metabolism of gamma-glutamylfelinylglycine in cats, generally occurs in a similar manner to glutathione S-conjugates in other animal species, although the detection of felinylglycine indicates that subtle differences may exist. Additionally, our research indicates that previously reported estimates of felinine excretion in male cats need to be increased by as much as 54% to account for other felinine containing metabolites in the urine.


Assuntos
Gatos/urina , Glutationa/análogos & derivados , Rim/metabolismo , Oligopeptídeos/isolamento & purificação , Oligopeptídeos/urina , Pentanóis/isolamento & purificação , Animais , Cromatografia Líquida de Alta Pressão , Glutationa/isolamento & purificação , Glutationa/urina , Masculino , Espectrometria de Massas , Oligopeptídeos/metabolismo , Pentanóis/urina , Especificidade da Espécie , Radioisótopos de Enxofre/urina
19.
Zhong Yao Cai ; 27(5): 337-9, 2004 May.
Artigo em Chinês | MEDLINE | ID: mdl-15376386

RESUMO

OBJECTIVE: To research the methods of purifying polyprenol from leaves of Ginkgo biloba L.. METHODS: The purity of polyprenol was determined by HPLC to select the optimal purifying conditions. RESULTS: The optimal conditions were degreased by 160 times of petroleum ether-ethyl acetate (9:1) firstly, then through a silica gel column (100-140 mesh) and eluted with petroleum etherethyl acetate (19:1). CONCLUSION: The methods are feasible to purify polyprenol from leaves of Ginkgo biloba L. and could increase the purity of polyprenol obviously.


Assuntos
Medicamentos de Ervas Chinesas/isolamento & purificação , Ginkgo biloba/química , Pentanóis/isolamento & purificação , Plantas Medicinais/química , Polímeros/isolamento & purificação , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/química , Etil-Éteres , Hemiterpenos , Pentanóis/análise , Folhas de Planta/química , Polímeros/análise
20.
Nat Prod Res ; 18(3): 215-7, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15143830

RESUMO

An aroma chemical emitted from Gerris paludum insularis was analyzed by means of GC and GC-MS. The main constituent was identified as iso amyl alcohol (3-methyl-1-butanol). The chemical showed a characteristic aroma of Gerris paludum insularis.


Assuntos
Insetos/química , Odorantes , Pentanóis/isolamento & purificação , Animais , Cromatografia Gasosa-Espectrometria de Massas , Pentanóis/química
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