Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 81
Filtrar
Mais filtros

Medicinas Complementares
Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Plant Physiol Biochem ; 198: 107679, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37121165

RESUMO

Plant cuticles cover aerial organs to limit non-stomatal water loss and protect against insects and pathogens. Cuticles contain complex mixtures of fatty acid-derived waxes, with various chain lengths and diverse functional groups. To further our understanding of the chemical diversity and biosynthesis of these compounds, this study investigated leaf cuticular waxes of Welsh onion (Allium fistulosum L.) wild type and a wax-deficient mutant. Leaf waxes were extracted with chloroform, separated using thin layer chromatography (TLC), and analyzed using gas chromatography-mass spectrometry (GC-MS). The extracts contained typical wax compound classes found in nearly all plant lineages but also two uncommon compound classes. Analyses of characteristic MS fragmentation patterns followed by comparisons with synthetic standards identified the latter as very-long-chain ketones and primary ketols. The ketols were minor compounds, with chain lengths ranging from C28 to C32 and carbonyls mainly on C-18 and C-20 in wild type wax, and a C28 chain with C-16 carbonyl in the mutant. The ketones made up 70% of total wax in the wild type, consisting mainly of C31 isomers with carbonyl group on C-14 or C-16. In contrast, the mutant wax comprised only 4% ketones, with chain lengths C27 and C29 and carbonyls predominantly on C-12 and C-14, respectively. A two-carbon homolog shift between wild type and mutant was also observed in the primary alcohols (a major wax compound class), whilst alkanes exhibited a four-carbon shift. Overall, the compositional data shed light on possible biosynthetic pathways to wax ketones that can be tested in future studies.


Assuntos
Allium , Ceras , Ceras/metabolismo , Cebolas/genética , Cebolas/metabolismo , Allium/metabolismo , Álcoois/análise , Álcoois/química , Álcoois/metabolismo , Folhas de Planta/metabolismo , Cetonas/análise , Cetonas/química , Cetonas/metabolismo , Carbono/metabolismo
2.
Front Immunol ; 11: 1533, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32793208

RESUMO

Pre-pregnancy body mass index (BMI) is a major relevance factor, since maternal overweight and obesity can impair the pregnancy outcome and represent risk factors for several neonatal, childhood, and adult conditions, including excessive weight gain, cardiovascular disease, diabetes mellitus, and even behavioral disorders. Currently, breast milk (BM) composition in such category of mothers was not completely defined. In this field, metabolomics represents the ideal technology, able to detect the whole profile of low molecular weight molecules in BM. Limited information is available on human BM metabolites differences in overweight or obese compared to lean mothers. Analyzing all the metabolomics studies published on Medline in English language, this review evaluated the effects that 8 specific types of metabolites found altered by maternal overweight and obesity (nucleotide derivatives, 5-methylthioadenosine, sugar-alcohols, acylcarnitine and amino acids, polyamines, mono-and oligosaccharides, lipids) can exert on the risk of offspring obesity development and other potentially associated health outcomes and complications. However, metabolites variations in samples collected from overweight and obese mothers and the potentially correlated effects highlighted below still need further investigations and should be confirmed in future metabolomics studies on larger samples. Finally, the positive or negative influence of maternal overweight and obesity on the offspring, potentially exerted by breastfeeding, should be analyzed in close correlation with maternal age, genetic and environmental factors, including diet, and taking into account the interactions occurring between BM metabolites and lactobiome. The evaluation of all the factors affecting BM metabolites in overweight and obese mothers can lead to the comprehensive description of such biofluid and the related effects on breastfed subjects, potentially highlighting personalized needs of BM supplementation or short- and long-term prevention strategies to optimize offspring health.


Assuntos
Metaboloma , Metabolômica , Leite Humano/metabolismo , Obesidade/metabolismo , Sobrepeso/metabolismo , Álcoois/metabolismo , Aminoácidos/metabolismo , Feminino , Humanos , Lipídeos/química , Leite Humano/imunologia , Nucleotídeos/metabolismo , Obesidade/imunologia , Sobrepeso/imunologia , Poliaminas/metabolismo , Gravidez , Açúcares/metabolismo
3.
J Food Sci ; 85(2): 306-315, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31976554

RESUMO

Wine yeast Saccharomyces cerevisiae 71B was used in fermentation of green tea to modulate the volatiles and nonvolatiles. After fermentation, higher alcohols, esters, and acids, such as isoamyl alcohol, isobutanol, ethyl octanoate, ethyl decanoate, octanoic, and decanoic acids were generated. Some key aroma compounds of tea including linalool, hotrienol, dihydroactinidiolide, and 2-phenylethanol increased significantly. Among these compounds, linalool and 2-phenylethanol increased by 1.3- and 10-fold, respectively, which impart floral and fruity notes to fermented green tea. Alkaloids including caffeine, theobromine, and theophylline were reduced significantly after fermentation, while the most important free amino acid in tea, theanine, was not metabolized by S. cerevisiae. Tea catechins decreased whereas gallic and caffeic acids increased significantly, resulting in the unchanged antioxidant capacity of the fermented green tea. Hence, this work highlighted the potential of using S. cerevisiae to modulate green tea aroma and nonvolatiles. PRACTICAL APPLICATION: A novel fermented tea is produced by yeast fermentation. Saccharomyces cerevisiae led to significant changes in tea volatiles and nonvolatiles. Antioxidant capacity remained stable after fermentation.


Assuntos
Camellia sinensis/microbiologia , Saccharomyces cerevisiae/metabolismo , Ácidos/análise , Ácidos/metabolismo , Álcoois/análise , Álcoois/metabolismo , Biotransformação , Camellia sinensis/metabolismo , Ésteres/análise , Ésteres/metabolismo , Fermentação , Odorantes/análise , Folhas de Planta/metabolismo , Folhas de Planta/microbiologia , Chá/metabolismo
4.
Bioresour Technol ; 283: 350-357, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30933901

RESUMO

Improving the economic feasibility is necessary for algae-based processes to achieve commercial scales for biofuels and bioproducts production. A closed-loop system for fusel alcohol production from microalgae biomass with integrated nutrient recycling was developed, which enables the reuse of nitrogen and phosphorus for downstream application and thus reduces the operational requirement for external major nutrients. Mixed fusel alcohols, primarily isobutanol and isopentanol were produced from Microchloropsis salina hydrolysates by an engineered E. coli co-culture. During the process, cellular nitrogen from microalgae biomass was converted into ammonium, whereas cellular phosphorus was liberated by an osmotic shock treatment. The formation of struvite from the liberated ammonium and phosphate, and the subsequent utilization of struvite to support M. salina cultivation was demonstrated. The closed loop system established here should help overcome one of the identified economic barriers to scale-up of microalgae production, and enhance the sustainability of microalgae-based chemical commodities production.


Assuntos
Álcoois/metabolismo , Biomassa , Microalgas/metabolismo , Nutrientes/metabolismo , Estramenópilas/metabolismo , Escherichia coli/metabolismo , Microalgas/crescimento & desenvolvimento , Nitrogênio/metabolismo , Fósforo/metabolismo , Reciclagem , Estramenópilas/crescimento & desenvolvimento , Estruvita/metabolismo
5.
Trends Biotechnol ; 37(8): 855-869, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30871798

RESUMO

'Higher' alcohols, which contain more than two carbons, have a higher boiling point, higher cetane number, and higher energy density than ethanol. Blends of biodiesel and higher alcohols can be used in internal combustion engines as next-generation biofuels without any modification and are minimally corrosive over extensive use. Producing higher alcohols from biomass involves fermenting and metabolizing amino acids. In this review, we describe the pathways and regulatory mechanisms involved in amino acid bioprocessing to produce higher alcohols and the effects of amino acid supplementation as a nitrogen source for higher alcohol production. We also discuss the most recent approaches to improve higher alcohol production via genetic engineering technologies for three microorganisms: Saccharomyces cerevisiae, Clostridium spp., and Escherichia coli.


Assuntos
Álcoois/metabolismo , Aminoácidos/metabolismo , Clostridium/metabolismo , Escherichia coli/metabolismo , Redes e Vias Metabólicas , Saccharomyces cerevisiae/metabolismo , Biotecnologia/métodos , Biotransformação , Clostridium/genética , Escherichia coli/genética , Saccharomyces cerevisiae/genética
6.
Food Microbiol ; 76: 354-362, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30166161

RESUMO

Due to the increasing consumer demand, the production of low alcoholic and non alcoholic beer is the new goal of the present brewing producers. Although the beer with reduced alcohol content is currently obtained by physical methods, the use of non-Saccharomyces yeast, with low fermentations capacities, may represent an interesting biological approach. In this study the ethanol content and the volatile profile of a beer obtained using the basidiomycetous psychrophilic yeast strain Mrakia gelida DBVPG 5952 was compared with that produced by a commercial starter for low alcohol beers, Saccharomycodes ludwigii WSL17. The two beers were characterized by a low alcohol content (1.40% and 1.32% v/v) and by a low diacetyl production (5.04 and 5.20 µg/L). However, the organoleptic characteristics of the beer obtained using M. gelida are more appreciated by the panelists, in comparison to the analogous produced with the commercial strain of S. ludwigii.


Assuntos
Álcoois/análise , Basidiomycota/metabolismo , Cerveja/análise , Álcoois/metabolismo , Cerveja/microbiologia , Diacetil/análise , Diacetil/metabolismo , Fermentação , Microbiologia de Alimentos , Humanos , Hypericum/química , Hypericum/metabolismo , Odorantes/análise , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Paladar
7.
Appl Microbiol Biotechnol ; 102(4): 1617-1628, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29353309

RESUMO

Cyanobacteria are photosynthetic prokaryotes that can fix atmospheric CO2 and can be engineered to produce industrially important compounds such as alcohols, free fatty acids, alkanes used in next-generation biofuels, and commodity chemicals such as ethylene or farnesene. They can be easily genetically manipulated, have minimal nutrient requirements, and are quite tolerant to abiotic stress making them an appealing alternative to other biofuel-producing microbes which require additional carbon sources and plants which compete with food crops for arable land. Many of the compounds produced in cyanobacteria are toxic as titers increase which can slow growth, reduce production, and decrease overall biomass. Additionally, many factors associated with outdoor culturing of cyanobacteria such as UV exposure and fluctuations in temperature can also limit the production potential of cyanobacteria. For cyanobacteria to be utilized successfully as biofactories, tolerance to these stressors must be increased and ameliorating stress responses must be enhanced. Genetic manipulation, directed evolution, and supplementation of culture media with antioxidants are all viable strategies for designing more robust cyanobacterial strains that have the potential to meet industrial production goals.


Assuntos
Biocombustíveis/toxicidade , Cianobactérias/efeitos dos fármacos , Cianobactérias/fisiologia , Tolerância a Medicamentos , Microbiologia Industrial/métodos , Estresse Fisiológico , Álcoois/metabolismo , Álcoois/toxicidade , Alcanos/metabolismo , Alcanos/toxicidade , Cianobactérias/genética , Etilenos/metabolismo , Etilenos/toxicidade , Ácidos Graxos/metabolismo , Ácidos Graxos/toxicidade , Engenharia Genética/métodos
8.
PLoS One ; 12(2): e0172682, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28234963

RESUMO

The study was focused on assessing the presence of arabinogalactan proteins (AGPs) and pectins within the cell walls as well as prenyl lipids, sodium and chlorine content in leaves of Tilia x euchlora trees. The leaves that were analyzed were collected from trees with and without signs of damage that were all growing in the same salt stress conditions. The reason for undertaking these investigations was the observations over many years that indicated that there are trees that present a healthy appearance and trees that have visible symptoms of decay in the same habitat. Leaf samples were collected from trees growing in the median strip between roadways that have been intensively salted during the winter season for many years. The sodium content was determined using atomic spectrophotometry, chloride using potentiometric titration and poly-isoprenoids using HPLC/UV. AGPs and pectins were determined using immunohistochemistry methods. The immunohistochemical analysis showed that rhamnogalacturonans I (RG-I) and homogalacturonans were differentially distributed in leaves from healthy trees in contrast to leaves from injured trees. In the case of AGPs, the most visible difference was the presence of the JIM16 epitope. Chemical analyses of sodium and chloride showed that in the leaves from injured trees, the level of these ions was higher than in the leaves from healthy trees. Based on chromatographic analysis, four poly-isoprenoid alcohols were identified in the leaves of T. x euchlora. The levels of these lipids were higher in the leaves from healthy trees. The results suggest that the differences that were detected in the apoplast and symplasm may be part of the defensive strategy of T. x euchlora trees to salt stress, which rely on changes in the chemical composition of the cell wall with respect to the pectic and AGP epitopes and an increased synthesis of prenyl lipids.


Assuntos
Adaptação Fisiológica , Parede Celular/efeitos dos fármacos , Lipídeos/biossíntese , Cloreto de Sódio/farmacologia , Estresse Fisiológico , Terpenos/metabolismo , Tilia/efeitos dos fármacos , Álcoois/isolamento & purificação , Álcoois/metabolismo , Parede Celular/química , Parede Celular/metabolismo , Lipídeos/isolamento & purificação , Mucoproteínas/biossíntese , Mucoproteínas/isolamento & purificação , Pectinas/biossíntese , Pectinas/isolamento & purificação , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Proteínas de Plantas/biossíntese , Proteínas de Plantas/isolamento & purificação , Salinidade , Solo/química , Terpenos/isolamento & purificação , Tilia/metabolismo , Árvores/efeitos dos fármacos , Árvores/metabolismo
9.
Bioresour Technol ; 219: 487-492, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27521785

RESUMO

Microwave enhanced fast and efficient alcoholysis (methanolysis and ethanolysis) of non-edible oils (algal, jatropha and pongamia) is achieved using chemically activated waste egg shell derived CaO (i.e. CaO(cesp)) as heterogeneous catalyst. CaO(cesp) was extracted from waste chicken egg shell and further activated chemically by supporting transition metal oxide. The maximum conversion was achieved using 3wt% catalysts under 700W microwave irradiation and 10:1 alcohol/oil ratio in 6min. Alcoholysis using ZnO activated CaO(cesp) catalyst has shown higher reaction yields in comparison to other modified catalysts. Methanolysis has shown better biodiesel conversion in comparison to ethanolysis. The catalyst has shown longer lifetime and sustained activity after being used for four cycles. Due to more saturated fatty acid content; algal biodiesel has shown improved fuel properties in comparison to other biodiesels.


Assuntos
Álcoois , Compostos de Cálcio/química , Casca de Ovo/química , Jatropha/química , Micro-Ondas , Óxidos/química , Óleos de Plantas , Pongamia/química , Álcoois/química , Álcoois/metabolismo , Animais , Biocombustíveis , Catálise , Óleos de Plantas/química , Óleos de Plantas/efeitos da radiação
10.
J Food Sci ; 81(8): C1908-13, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27384350

RESUMO

The inhibitory effect of 10 flavonoids on the formation of 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) in a creatinine-phenylalanine model system was investigated through electronic spin resonance and a quantitative structure-activity relationship. Alkoxy radicals were observed during the heating process, providing evidence for a radical pathway in the formation of PhIP. The alkoxy radical scavenging capability of the flavonoids was proportional to their inhibition of PhIP formation (IC50 ). We deduced that flavonoid inhibition of PhIP generation occurs via scavenging of alkoxy radicals during the heating process. Multiple linear regression and partial least squares models were used to elucidate the relationship between PhIP inhibition activity and structure characteristics of the flavonoids. The lipo-hydro partition coefficient and molecular fractional polar surface area of the flavonoids were found to be predictive of the inhibition effect.


Assuntos
Álcoois/metabolismo , Carcinógenos/metabolismo , Flavonoides/farmacologia , Radicais Livres/metabolismo , Imidazóis/metabolismo , Extratos Vegetais/farmacologia , Relação Quantitativa Estrutura-Atividade , Animais , Creatinina/metabolismo , Flavonoides/química , Compostos Heterocíclicos/metabolismo , Modelos Biológicos , Fenilalanina/metabolismo , Piridinas/metabolismo
11.
J Chem Inf Model ; 56(7): 1313-23, 2016 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-27387009

RESUMO

Zinc-dependent medium chain reductase from Candida parapsilosis can be used in the reduction of carbonyl compounds to pharmacologically important chiral secondary alcohols. To date, the nomenclature of cpADH5 is differing (CPCR2/RCR/SADH) in the literature, and its natural substrate is not known. In this study, we utilized a substrate docking based virtual screening method combined with KEGG, MetaCyc pathway, and Candida genome databases search for the discovery of natural substrates of cpADH5. The virtual screening of 7834 carbonyl compounds from the ZINC database provided 94 aldehydes or methyl/ethyl ketones as putative carbonyl substrates. Out of which, 52 carbonyl substrates of cpADH5 with catalytically active docking pose were identified by employing mechanism based substrate docking protocol. Comparison of the virtual screening results with KEGG, MetaCyc database search, and Candida genome pathway analysis suggest that cpADH5 might be involved in the Ehrlich pathway (reduction of fusel aldehydes in leucine, isoleucine, and valine degradation). Our QM/MM calculations and experimental activity measurements affirmed that butyraldehyde substrates are the potential natural substrates of cpADH5, suggesting a carbonyl reductase role for this enzyme in butyraldehyde reduction in aliphatic amino acid degradation pathways. Phylogenetic tree analysis of known ADHs from Candida albicans shows that cpADH5 is close to caADH5. We therefore propose, according to the experimental substrate identification and sequence similarity, the common name butyraldehyde dehydrogenase cpADH5 for Candida parapsilosis CPCR2/RCR/SADH.


Assuntos
Álcool Desidrogenase/metabolismo , Candida/enzimologia , Candida/genética , Bases de Dados Genéticas , Genômica/métodos , Álcool Desidrogenase/química , Álcoois/metabolismo , Sequência de Aminoácidos , Avaliação Pré-Clínica de Medicamentos/métodos , Cinética , NAD/metabolismo , Conformação Proteica , Teoria Quântica , Especificidade por Substrato , Interface Usuário-Computador
12.
Enzyme Microb Technol ; 90: 35-44, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27241290

RESUMO

Industrial use of Novozym 435 in synthesis of structured lipids and biodiesel via alcoholysis is limited by mass transfer effects of the glycerides through immobilized enzymes and its low operational stability under operation conditions. To better understand this, differently modified Novozym 435 preparations, differing in their surface nature and in their interactions with reactants, have been compared in the alcoholysis of Camelina sativa oil. The three modifications performed have been carried out under conditions where all exposed groups of the enzyme have been modified. These modifications were: 2,4,6-trinitrobenzensulfonic acid (Novo-TNBS), ethylendiamine (Novo-EDA) and polyethylenimine (Novo-PEI). Changes in their operational performance are analyzed in terms of changes detected by scan electron microscopy in the support morphology. The hydrophobic nature of the TNBS accelerates the reaction rate; t-ButOH co-solvent swells the macroporous acrylic particles of Lewatit VP OC 1600 in all biocatalysts, except in the case of Novo-PEI. This co-solvent only increases the maximal conversions obtained at 24h using the modified biocatalysts. t-ButOH reduces enzyme inactivation by alcohol and water. In a co-solvent system, these four biocatalysts remain fully active after 14 consecutive reaction cycles of 24h, but only Novo-TNBS yields maximal conversion before cycle 5. Some deposits on biocatalyst particles could be appreciated during reuses, and TNBS derivatization diminishes the accumulation of product deposits on the catalyst surface. Most particles of commercial Novozym(®) 435 are broken after operation for 14 reaction cycles. The broken particles are fully active, but they cause problems of blockage in filtration operations and column reactors. The three derivatizations studied make the matrix particles more resistant to rupture.


Assuntos
Lipase/química , Lipase/metabolismo , Álcoois/química , Álcoois/metabolismo , Biocatálise , Biotecnologia , Estabilidade Enzimática , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Enzimas Imobilizadas/ultraestrutura , Etilenodiaminas/química , Proteínas Fúngicas , Lipase/ultraestrutura , Microscopia Eletrônica de Varredura , Óleos de Plantas/química , Óleos de Plantas/metabolismo , Polietilenoimina/química , Ácido Trinitrobenzenossulfônico/química
13.
Appl Microbiol Biotechnol ; 100(11): 4735-45, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27087523

RESUMO

Enhanced biological phosphorus removal (EBPR) process is one of the most economical and sustainable methods for phosphorus removal from wastewater. However, the performance of EBPR can be affected by available carbon sources types in the wastewater that may induce different functional microbial communities in the process. Glycogen accumulating organisms (GAOs) and polyphosphate accumulating organisms (PAOs) are commonly found by coexisting in the EBPR process. Predominance of GAO population may lead to EBPR failure due to the competition on carbon source with PAO without contributing phosphorus removal. Carbon sources indeed play an important role in alteration of PAOs and GAOs in EBPR processes. Various types of carbon sources have been investigated for EBPR performance. Certain carbon sources tend to enrich specific groups of GAOs and/or PAOs. This review summarizes the types of carbon sources applied in EBPR systems and highlights the roles of these carbon sources in PAO and GAO competition. Both single (e.g., acetate, propionate, glucose, ethanol, and amino acid) and complex carbon sources (e.g., yeast extract, peptone, and mixed carbon sources) are discussed in this review. Meanwhile, the environmental friendly and economical carbon sources that are derived from waste materials, such as crude glycerol and wasted sludge, are also discussed and compared.


Assuntos
Carbono/química , Fósforo/isolamento & purificação , Purificação da Água/métodos , Acetatos/metabolismo , Álcoois/metabolismo , Aminoácidos/metabolismo , Biodegradação Ambiental , Ciclo do Ácido Cítrico , Glucose/metabolismo , Glicerol/metabolismo , Glicogênio/metabolismo , Polifosfatos/metabolismo , Propionatos/metabolismo , Águas Residuárias/microbiologia
14.
Nat Prod Commun ; 11(1): 49-51, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26996018

RESUMO

Two new compounds, a quinoline alkaloid (1) and a 1,4-dioxane derivative (2), were isolated from culture broth of the marine-derived actinomycete Micromonospora sp. (strain G019) by bioassay-guided fractionation. This actinomycete strain was isolated from sediment, collected at Cát Bà Peninsula, Vietnam. The taxonomic identification was achieved by analysis of 16S rRNA gene sequences. On the basis of morphological and phylogenetic evidence, strain G019 was assigned to the genus Micromonospora. The structures of 1 and 2 were established by spectroscopic data analysis, including one- and two-dimensional NMR, and MS. Compound 1 was found to have antibacterial activity against Escherichia coli (MIC: 48 µg/mL), Salmonella enterica (MIC: 96 µg/mL) and Enterococcus faecalis (MIC: 128 µg/mL), while compound 2 showed inhibitory activity against Enterococcusfaecalis (MIC: 32 µg/mL) and Candida albicans (MIC: 64 µg/mL).


Assuntos
Actinobacteria/metabolismo , Álcoois/farmacologia , Alcaloides/farmacologia , Antibacterianos/metabolismo , Antifúngicos/metabolismo , Dioxanos/farmacologia , Etanol/análogos & derivados , Quinolinas/farmacologia , Actinobacteria/química , Actinobacteria/genética , Álcoois/química , Álcoois/metabolismo , Alcaloides/química , Alcaloides/metabolismo , Antibacterianos/química , Antifúngicos/química , Bactérias/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Dioxanos/química , Dioxanos/metabolismo , Etanol/química , Etanol/metabolismo , Etanol/farmacologia , Sedimentos Geológicos/microbiologia , Testes de Sensibilidade Microbiana , Estrutura Molecular , Oceanos e Mares , Quinolinas/química , Quinolinas/metabolismo , Vietnã
15.
Microb Cell Fact ; 14: 16, 2015 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-25889648

RESUMO

Early trials have demonstrated great potential for the use of duckweed (family Lemnaceae) as the next generation of energy plants for the production of biofuels. Achieving this technological advance demands research to develop novel bioengineering microorganisms that can ferment duckweed feedstock to produce higher alcohols. In this study, we used relevant genes to transfer five metabolic pathways of isoleucine, leucine and valine from the yeast Saccharomyces cerevisiae into the bioengineered microorganism Corynebacterium crenatum. Experimental results showed that the bioengineered strain was able to produce 1026.61 mg/L of 2-methyl-1-butanol by fermenting glucose, compared to 981.79 mg/L from the acid hydrolysates of duckweed. The highest isobutanol yields achieved were 1264.63 mg/L from glucose and 1154.83 mg/L from duckweed, and the corresponding highest yields of 3-methyl-1-butanol were 748.35 and 684.79 mg/L. Our findings demonstrate the feasibility of using bioengineered C. crenatum as a platform to construct a bacterial strain that is capable of producing higher alcohols. We have also shown the promise of using duckweed as the basis for developing higher alcohols, illustrating that this group of plants represents an ideal fermentation substrate that can be considered the next generation of alternative energy feedstocks.


Assuntos
Álcoois/metabolismo , Araceae/química , Biocombustíveis , Corynebacterium/metabolismo , Engenharia Metabólica/métodos , Extratos Vegetais/metabolismo , Butanóis/metabolismo , Corynebacterium/genética , Fermentação , Expressão Gênica , Glucose/metabolismo , Hidrólise , Isoleucina/metabolismo , Leucina/metabolismo , Redes e Vias Metabólicas/genética , Reprodutibilidade dos Testes , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Amido/metabolismo , Valina/metabolismo
16.
J Biosci Bioeng ; 119(3): 280-3, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25204793

RESUMO

Biolubricants from Castor oil were produced enzymatically by transesterification with higher alcohols using a lipase mixture of immobilized Mucor miehei (RMIM) and immobilized Candida antarctica lipase B (Novozym 435) under low water conditions. The conversions were in the range of 80-95% under the optimized conditions.


Assuntos
Álcoois/química , Álcoois/metabolismo , Óleo de Rícino/química , Óleo de Rícino/metabolismo , Enzimas Imobilizadas/metabolismo , Proteínas Fúngicas/metabolismo , Lipase/metabolismo , Esterificação , Mucor/enzimologia , Água/análise , Água/metabolismo
17.
Food Microbiol ; 44: 87-95, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25084650

RESUMO

The aim of this study was to evaluate the use of yeasts as starter cultures in coffee semi-dry processing. Arabica coffee was inoculated with one of the following starter cultures: Saccharomyces cerevisiae UFLA YCN727, S. cerevisiae UFLA YCN724, Candida parapsilosis UFLA YCN448 and Pichia guilliermondii UFLA YCN731. The control was not inoculated with a starter culture. Denaturing gradient gel electrophoresis (DGGE) was used to assess the microbial population, and organic acids and volatile compounds were quantified by HPLC and HS-SPME/GC, respectively. Sensory analyses were evaluated using the Temporal Dominance of Sensations (TDS). DGGE analysis showed that the inoculated yeasts were present throughout the fermentation. Other yeast species were also detected, including Debaryomyces hansenii, Cystofilobasidium ferigula and Trichosporon cavernicola. The bacterial population was diverse and was composed of the following genera: Weissella, Leuconostoc, Gluconobacter, Pseudomonas, Pantoea, Erwinia and Klebsiella. Butyric and propionic acids, were not detected in any treatment A total of 47 different volatiles compounds have been identified. The coffee inoculated with yeast had a caramel flavor that was not detected in the control, as assessed by TDS. The use of starter cultures during coffee fermentation is an interesting alternative for obtaining a beverage quality with distinctive flavor.


Assuntos
Coffea/microbiologia , Leveduras/metabolismo , Álcoois/metabolismo , Aldeídos/metabolismo , Coffea/química , Coffea/metabolismo , Café/química , Fermentação , Humanos , Paladar , Leveduras/classificação , Leveduras/genética , Leveduras/isolamento & purificação
18.
Photosynth Res ; 122(1): 69-86, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24880610

RESUMO

A chlorosome is an antenna complex located on the cytoplasmic side of the inner membrane in green photosynthetic bacteria that contains tens of thousands of self-assembled bacteriochlorophylls (BChls). Green bacteria are known to incorporate various esterifying alcohols at the C-17 propionate position of BChls in the chlorosome. The effect of these functional substitutions on the biogenesis of the chlorosome has not yet been fully explored. In this report, we address this question by investigating various esterified bacteriochlorophyll c (BChl c) homologs in the thermophilic green non-sulfur bacterium Chloroflexus aurantiacus. Cultures were supplemented with exogenous long-chain alcohols at 52 °C (an optimal growth temperature) and 44 °C (a suboptimal growth temperature), and the morphology, optical properties and exciton transfer characteristics of chlorosomes were investigated. Our studies indicate that at 44 °C Cfl. aurantiacus synthesizes more carotenoids, incorporates more BChl c homologs with unsaturated and rigid polyisoprenoid esterifying alcohols and produces more heterogeneous BChl c homologs in chlorosomes. Substitution of phytol for stearyl alcohol of BChl c maintains similar morphology of the intact chlorosome and enhances energy transfer from the chlorosome to the membrane-bound photosynthetic apparatus. Different morphologies of the intact chlorosome versus in vitro BChl aggregates are suggested by small-angle neutron scattering. Additionally, phytol cultures and 44 °C cultures exhibit slow assembly of the chlorosome. These results suggest that the esterifying alcohol of BChl c contributes to long-range organization of BChls, and that interactions between BChls with other components are important to the assembly of the chlorosome. Possible mechanisms for how esterifying alcohols affect the biogenesis of the chlorosome are discussed.


Assuntos
Proteínas de Bactérias/química , Bacterioclorofilas/química , Chloroflexus/química , Organelas/metabolismo , Ficobiliproteínas/química , Álcoois/metabolismo , Proteínas de Bactérias/metabolismo , Bacterioclorofilas/metabolismo , Carotenoides/metabolismo , Chloroflexus/fisiologia , Cromatografia Líquida , Transferência de Energia , Esterificação , Organelas/química , Ficobiliproteínas/metabolismo , Espectrometria de Massas em Tandem , Temperatura
19.
Phytochemistry ; 93: 105-15, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23578960

RESUMO

Withania somnifera (L.) Dunal (Solanaceae), commonly known as Ashwagandha, is one of the most valued Indian medicinal plant with several pharmaceutical and nutraceutical applications. Metabolic profiling was performed by GC-MS and NMR spectroscopy on the fruits obtained from four chemotypes of W. somnifera. A combination of (1)H NMR spectroscopy and GC-MS identified 82 chemically diverse metabolites consisting of organic acids, fatty acids, aliphatic and aromatic amino acids, polyols, sugars, sterols, tocopherols, phenolic acids and withanamides in the fruits of W. somnifera. The range of metabolites identified by GC-MS and NMR of W. somnifera fruits showed various known and unknown metabolites. The primary and secondary metabolites observed in this study represent MVA, DOXP, shikimic acid and phenylpropanoid biosynthetic metabolic pathways. Squalene and tocopherol have been rated as the most potent naturally occurring compounds with antioxidant properties. These compounds have been identified by us for the first time in the fruits of W. somnifera. Multivariate principal component analysis (PCA) on GC-MS and NMR data revealed clear distinctions in the primary and secondary metabolites among the chemotypes. The variation in the metabolite concentration among different chemotypes of the fruits of W. somnifera suggest that specific chemovars can be used to obtain substantial amounts of bioactive ingredients for use as potential pharmacological and nutraceuticals agents.


Assuntos
Frutas/química , Withania/química , Álcoois/química , Álcoois/metabolismo , Aminoácidos Aromáticos/química , Aminoácidos Aromáticos/metabolismo , Carboidratos/química , Dissacarídeos/química , Dissacarídeos/metabolismo , Ácidos Graxos/química , Ácidos Graxos/metabolismo , Frutas/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Hidroxibenzoatos/química , Hidroxibenzoatos/metabolismo , Espectroscopia de Ressonância Magnética , Análise de Componente Principal , Esteróis/química , Esteróis/metabolismo , Withania/metabolismo
20.
Adv Exp Med Biol ; 776: 21-8, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23392867

RESUMO

Excessive alcohol consumption is dangerous and causes serious damage to health. The main organ capable of alcohol oxidizing is liver which is also the main organ synthesizing taurine, a sulfur-containing ß-amino acid, which is the major free intracellular amino acid presenting in many tissues of human and animals and exerting many physiologic and pharmacologic functions. To investigate the effect of taurine and Chinese traditional medicine on alcohol metabolism after acute alcoholic intake, male Kunming mice were administered with 60% alcohol (0.4 ml) intragastrically. Water, taurine, or taurine coadministration with Chinese traditional medicine was intragastrically administered to mice 30 min before or after alcohol intake. The disappearance of body-righting reflex was used to determine the intoxication of mice. Durations between alcohol intake and intoxication (tolerance time), intoxication and recovery (maintenance time) were recorded. The concentration of blood alcohol, levels of hepatic alcohol dehydrogenase (ADH), and acetaldehyde dehydrogenase (ALDH) were detected at 20, 50, 90, 120, and 150 min after alcohol intake. The results showed that taurine administered alone or together with Chinese traditional medicine could both significantly reduce the number of intoxicated mice, postpone the tolerance time, shorten the maintenance time, and could obvisouly decrease blood level of alcohol, increase hepatic levels of ADH and ALDH. The results indicated that taurine administered alone or together with traditional Chinese medicine could significantly accelerate the metabolism of alcohol, reduce the toxicity of alcohol, and coadministration of taurine and traditional Chinese medicine had better effects.


Assuntos
Álcoois/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Medicina Tradicional Chinesa , Taurina/farmacologia , Álcool Desidrogenase/metabolismo , Intoxicação Alcoólica/sangue , Intoxicação Alcoólica/tratamento farmacológico , Álcoois/sangue , Aldeído Desidrogenase/metabolismo , Animais , Medicamentos de Ervas Chinesas/administração & dosagem , Medicamentos de Ervas Chinesas/uso terapêutico , Humanos , Fígado/enzimologia , Masculino , Camundongos , Taurina/administração & dosagem , Taurina/uso terapêutico
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA