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1.
J Sci Food Agric ; 2024 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-39412364

RESUMO

BACKGROUND: Postweaning intestinal damage in piglets is a challenging issue in the livestock industry. Short-chain fatty acids (SCFAs) are important metabolic products of the gut microbiota and are widely recognized for their role in maintaining normal colonic function and regulating the intestinal immune system. However, the effects of branched short-chain fatty acid (BSCFA) isobutyrate on intestinal health remain largely unknown. This study aims to explore the potential of isobutyrate for alleviating postweaning intestinal damage. RESULTS: This study indicates that isobutyrate can alleviate diarrhea in weaned piglets, enhance their growth performance, and optimize the gut microbiota. This is mainly achieved through increasing the relative abundance of probiotic bacteria such as Lactobacillus, Megasphaera, and Prevotellaceae_UCG-003, while concurrently reducing the relative abundance of potentially harmful bacteria such as Clostridium_sensu_stricto-1 and Escherichia-Shigella. It promotes the production of SCFAs, including acetate, isobutyrate, and butyrate. Furthermore, it activates G-protein-coupled receptors (GPR43/109A), inhibits the TLR4/MyD88 signaling pathway, strengthens the intestinal barrier function, and regulates the expression of related cytokines. CONCLUSION: In summary, exogenous isobutyrate can be considered a promising feed additive for improving the intestinal microbiota and regulating intestinal health in piglets. © 2024 Society of Chemical Industry.

2.
AAPS PharmSciTech ; 25(7): 202, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39237685

RESUMO

The focus of the present work was to develop amorphous solid dispersion (ASD) formulation of aprepitant (APT) using sucrose acetate isobutyrate (SAIB) excipient, evaluate for physicochemical attributes, stability, and bioavailability, and compared with hydroxypropyl methylcellulose (HPMC) based formulation. Various formulations of APT were prepared by solvent evaporation method and characterized for physiochemical and in-vivo performance attributes such as dissolution, drug phase, stability, and bioavailability. X-ray powder diffraction indicated crystalline drug conversion into amorphous phase. Dissolution varied as a function of drug:SAIB:excipient proportion. The dissolution was more than 80% in the optimized formulation (F10) and comparable to HPMC based formulation (F13). Stability of F10 and F13 formulations stored at 25 C/60% and 40°C/75% RH for three months were comparable. Both ASD formulations (F10 and F13) were bioequivalent as indicated by the pharmacokinetic parameters Cmax and AUC0-∞. Cmax and AUC0-∞ of F10 and F13 formulations were 2.52 ± 0.39, and 2.74 ± 0.32 µg/ml, and 26.59 ± 0.39, and 24.79 ± 6.02 µg/ml.h, respectively. Furthermore, the bioavailability of ASD formulation was more than twofold of the formulation containing crystalline phase of the drug. In conclusion, stability and oral bioavailability of SAIB based ASD formulation is comparable to HPMC-based formulation of poorly soluble drugs.


Assuntos
Disponibilidade Biológica , Excipientes , Solubilidade , Sacarose , Sacarose/análogos & derivados , Sacarose/química , Administração Oral , Animais , Excipientes/química , Masculino , Derivados da Hipromelose/química , Química Farmacêutica/métodos , Estabilidade de Medicamentos , Difração de Raios X/métodos
3.
Int J Mol Sci ; 24(10)2023 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-37240050

RESUMO

Anxiety is one of the most common central nervous system disorders, affecting at least one-quarter of the worldwide population. The medications routinely used for the treatment of anxiety (mainly benzodiazepines) are a cause of addiction and are characterized by many undesirable side effects. Thus, there is an important and urgent need for screening and finding novel drug candidates that can be used in the prevention or treatment of anxiety. Simple coumarins usually do not show side effects, or these effects are much lower than in the case of synthetic drugs acting on the central nervous system (CNS). This study aimed to evaluate the anxiolytic activity of three simple coumarins from Peucedanum luxurians Tamamsch, namely officinalin, stenocarpin isobutyrate, and officinalin isobutyrate, in a 5 dpf larval zebrafish model. Moreover, the influence of the tested coumarins on the expression of genes involved in the neural activity (c-fos, bdnf) or dopaminergic (th1), serotoninergic (htr1Aa, htr1b, htr2b), GABA-ergic (gabarapa, gabarapb), enkephalinergic (penka, penkb), and galaninergic (galn) neurotransmission was assessed by quantitative PCR. All tested coumarins showed significant anxiolytic activity, with officinalin as the most potent compound. The presence of a free hydroxyl group at position C-7 and the lack of methoxy moiety at position C-8 might be key structural features responsible for the observed effects. In addition, officinalin and its isobutyrate upregulated the expression of genes involved in neurotransmission and decreased the expression of genes connected with neural activity. Therefore, the coumarins from P. luxurians might be considered as promising drug candidates for the therapy of anxiety and related disorders.


Assuntos
Ansiolíticos , Animais , Ansiolíticos/farmacologia , Peixe-Zebra/genética , Frutas/química , Isobutiratos/análise , Ansiedade/tratamento farmacológico , Ansiedade/metabolismo , Cumarínicos/química , Expressão Gênica
4.
Pharm Dev Technol ; 28(10): 928-938, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37870222

RESUMO

This study aims to improve the RXB bioavailability using hybrid nanoparticles. A modified melt dispersion technique created different formulas with varying GMO-SAIB: RXB and GMO: SAIB ratios, with fixed GMO-SAIB: poloxamer 407 ratios. The PS, PDI, ZP, and EE were measured to determine the optimal formula, which was selected using Design-Expert™ software. The optimized formula was lyophilized and tested for PS, PDI, ZP, and EE. The chosen lyophilized formula (L4) was characterized using FTIR, DSC, PXRD, dissolution studies, and pharmacokinetics studies. The study found correlations between variables and identified how GMO-SAIB concentration affects drug encapsulation. The dissolution parameters were calculated, including % Q5 and % DE). The % Q5 values were 68.4 ± 1.7% and 89.7 ± 3.6% for Xarelto and L4 tablets, respectively. The % DE values were 89.7 ± 0.4% and 97.5 ± 2.1% for Xarelto and L4 tablets, respectively. The AUC values were 2117.0 ng.h/mL (±77.3) and 3919.4 ng.h/mL (±134.8) for Xarelto and L4 tablets, respectively. The Cmax values were 241.3 ng/mL (±21.0) and 521.5 ng/mL (±91.5) for Xarelto and L4 tablets, respectively. In conclusion, the study found that using GMO-SAIB as co-formers effectively enhanced the bioavailability of RXB. The authors recommend using the hybrid nanoparticles technique and suggest further research to enhance its effectiveness for drug delivery.


Assuntos
Nanopartículas , Rivaroxabana , Plantas Geneticamente Modificadas , Disponibilidade Biológica , Sacarose
5.
Appl Microbiol Biotechnol ; 106(2): 605-618, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34985570

RESUMO

Using microbial enrichment cultures for the production of waste-derived polyhydroxyalkanoates (PHAs) is a promising technology to recover secondary resources. Volatile fatty acids (VFAs) form the preferred substrate for PHA production. Isobutyrate is a VFA appearing in multiple waste valorization routes, such as anaerobic fermentation, chain elongation, and microbial electrosynthesis, but has never been assessed individually on its PHA production potential. This research investigates isobutyrate as sole carbon source for a microbial enrichment culture in comparison to its structural isomer butyrate. The results reveal that the enrichment of isobutyrate has a very distinct character regarding microbial community development, PHA productivity, and even PHA composition. Although butyrate is a superior substrate in almost every aspect, this research shows that isobutyrate-rich waste streams have a noteworthy PHA-producing potential. The main finding is that the dominant microorganism, a Comamonas sp., is linked to the production of a unique PHA family member, poly(3-hydroxyisobutyrate) (PHiB), up to 37% of the cell dry weight. This is the first scientific report identifying microbial PHiB production, demonstrating that mixed microbial communities can be a powerful tool for discovery of new metabolic pathways and new types of polymers. KEY POINTS: • PHiB production is a successful storage strategy in an isobutyrate-fed SBR • Isomers isobutyrate and butyrate reveal a very distinct PHA production behavior • Enrichments can be a tool for discovery of new metabolic pathways and polymers.


Assuntos
Reatores Biológicos , Poli-Hidroxialcanoatos , Ácidos Graxos Voláteis , Fermentação , Isobutiratos , Poli-Hidroxialcanoatos/metabolismo
6.
Pediatr Allergy Immunol ; 32(2): 264-272, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32920883

RESUMO

BACKGROUND: There remains an unmet need in objective tests for diagnosing asthma in children. The objective of this study was to investigate the potential of metabolomic profiles of exhaled breath condensate (EBC) to discriminate stable asthma in Asian children in the community. METHODS: One hundred and sixty-five Asian children (92 stable asthma and 73 non-asthmatic controls) participating in a population-based cohort were enrolled and divided into training and validation sets. Nuclear magnetic resonance-based metabolomic profiles of EBC samples were analyzed by using orthogonal partial least squares discriminant analysis. RESULTS: EBC metabolomic signature (lactate, formate, butyrate, and isobutyrate) had an area under the receiver operator characteristic curve (AUC) of 0.826 in discriminating children with and without asthma in the training set, which significantly outperformed FeNO (AUC = 0.574; P < .001) and FEV1 /FVC % predicted (AUC = 0.569; P < .001). The AUC for EBC metabolomic signature was 0.745 in the validation set, which was slightly but not significantly lower than in the testing set (P = .282). We further extrapolated two potentially involved metabolic pathways, including pyruvate (P = 1.67 × 10-3 ; impact: 0.14) and methane (P = 1.89 × 10-3 ; impact: 0.15), as the most likely divergent metabolisms between children with and without asthma. CONCLUSION: This study provided evidence supporting the role of EBC metabolomic signature to discriminate stable asthma in Asian children in the community, with a discriminative property outperforming conventional clinical tests such as FeNO or spirometry.


Assuntos
Asma , Expiração , Asma/diagnóstico , Biomarcadores , Testes Respiratórios , Criança , Humanos , Óxido Nítrico , Espirometria
7.
Bioorg Med Chem ; 46: 116364, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34450570

RESUMO

The nucleoside metabolite of remdesivir, GS-441524 displays potent anti-SARS-CoV-2 efficacy, and is being evaluated in clinical as an oral antiviral therapeutic for COVID-19. However, this nucleoside has a poor oral bioavailability in non-human primates, which may affect its therapeutic efficacy. Herein, we reported a variety of GS-441524 analogs with modifications on the base or the sugar moiety, as well as some prodrug forms, including five isobutyryl esters, two l-valine esters, and one carbamate. Among the new nucleosides, only the 7-fluoro analog 3c had moderate anti-SARS-CoV-2 activity, and its phosphoramidate prodrug 7 exhibited reduced activity in Vero E6 cells. As for the prodrugs, the 3'-isobutyryl ester 5a, the 5'-isobutyryl ester 5c, and the tri-isobutyryl ester 5g hydrobromide showed excellent oral bioavailabilities (F = 71.6%, 86.6% and 98.7%, respectively) in mice, which provided good insight into the pharmacokinetic optimization of GS-441524.


Assuntos
Adenosina/análogos & derivados , Antivirais/farmacologia , SARS-CoV-2/efeitos dos fármacos , Adenosina/farmacocinética , Adenosina/farmacologia , Adenosina/toxicidade , Animais , Antivirais/síntese química , Antivirais/farmacocinética , Antivirais/toxicidade , Chlorocebus aethiops , Masculino , Camundongos Endogâmicos ICR , Testes de Sensibilidade Microbiana , Pró-Fármacos/síntese química , Pró-Fármacos/farmacocinética , Pró-Fármacos/farmacologia , Pró-Fármacos/toxicidade , Células Vero
8.
J Chem Ecol ; 47(8-9): 732-739, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34347234

RESUMO

The pine brown tail moth, Euproctis terminalis (Walker 1855), is a periodic pest in pine plantations in South Africa. The larvae feed on pine needles and can cause severe defoliation when population densities are high. Population densities fluctuate temporally and spatially, complicating the prediction of potential growth loss and tree mortality. The aim of this study was to identify the sex pheromone of the pine brown tail moth to provide stakeholders with a tool for monitoring it. Gas chromatography-electroantennogram detection and gas chromatography/mass spectrometry analyses of female pheromone gland extracts identified the major component as (Z,Z,Z,Z)-7,13,16,19-docosatetraen-1-ol isobutyrate. Traps baited with (Z,Z,Z,Z)-7,13,16,19-docosatetraen-1-ol isobutyrate caught more males than unbaited traps. A delta trap was shown to be a superior design compared to a bucket funnel trap. This pheromone can now be used for monitoring E. terminalis in pine plantations.


Assuntos
Mariposas/fisiologia , Atrativos Sexuais/análise , Animais , DNA/química , Complexo IV da Cadeia de Transporte de Elétrons/genética , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Isobutiratos/análise , Isobutiratos/farmacologia , Larva/crescimento & desenvolvimento , Masculino , Mariposas/química , Mariposas/crescimento & desenvolvimento , Pinus/parasitologia , Análise de Sequência de DNA , Atrativos Sexuais/farmacologia , Comportamento Sexual Animal/efeitos dos fármacos
9.
Phytother Res ; 35(10): 5741-5753, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34355433

RESUMO

Currently available therapies for hepatocellular carcinoma (HCC), with a high morbidity and high mortality, are only marginally effective and with sharp adverse side effects, which makes it compulsory to explore novel and more effective anticancer molecules. Chinese medicinal herbs exhibited prominent anticancer effects and were applied to supplement clinical cancer treatment. Here, we reported a compound, trilobolide-6-O-isobutyrate (TBB), isolated from the flowers of Wedelia trilobata with a markedly cytotoxic effect on HCC cells. We found that TBB time- and dose-dependently inhibited HCC cells' growth and colony formation in vitro. Moreover, TBB induced cell cycle arrest at the G2/M phase, mitochondrial caspase-dependent apoptosis, and suppressed migration and invasion, as well as the glycolysis of HCC cells. Mechanistically, our data indicated that TBB inhibited the STAT3 pathway activation by directly interacting with the TYR 640/657 sites of the STAT3 protein and decreasing the level of p-STAT3. TBB also regulated the expression of PCNA, Ki67, Cyclin B1, Cyclin E, Bax, Bcl2, MMP2/9, and PGK1 through the inhibition of the IL-6/STAT3 signaling pathway. Lastly, we confirmed that TBB effectively eliminated tumor growth without causing overt toxicity to healthy tissues in the xenograft tumor model. The exploration of anticancer activity and the underlying mechanism of TBB suggested its usage as a promising chemotherapeutic agent for HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Apoptose , Butiratos , Carcinogênese , Carcinoma Hepatocelular/tratamento farmacológico , Linhagem Celular Tumoral , Proliferação de Células , Furanos , Humanos , Interleucina-6/metabolismo , Isobutiratos , Neoplasias Hepáticas/tratamento farmacológico , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais
10.
Int J Mol Sci ; 22(16)2021 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-34445372

RESUMO

The synthesis of ester compounds is one of the most important chemical processes. In this work, Zn-Mg-Al mixed oxides with different Zn2+/Mg2+ molar ratios were prepared via co-precipitation method and supported gold nanoclusters to study the direct oxidative esterification of aldehyde and alcohol in the presence of molecular oxygen. Various characterization techniques such as N2-physical adsorption, X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and CO2 temperature programmed desorption (TPD) were utilized to analyze the structural and electronic properties. Based on the results, the presence of small amounts of Zn2+ ions (~5 wt.%) provoked a remarkable modification of the binary Mg-Al system, which enhanced the interaction between gold with the support and reduced the particle size of gold. For oxidative esterification reaction, the Au25/Zn0.05MgAl-400 catalyst showed the best performance, with the highest turnover frequency (TOF) of 1933 h-1. The active center was believed to be located at the interface between metallic gold with the support, where basic sites contribute a lot to transformation of the substrate.


Assuntos
Aldeídos/química , Hidróxido de Alumínio/química , Ouro/química , Hidróxido de Magnésio/química , Óxidos/química , Esterificação , Nanopartículas Metálicas , Microscopia Eletrônica de Transmissão , Oxirredução , Estresse Oxidativo , Tamanho da Partícula , Difração de Raios X , Zinco
11.
AAPS PharmSciTech ; 23(1): 35, 2021 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-34950995

RESUMO

The focus of the present investigation was to develop amorphous glassy solutions (AGSs) of BCS Class II and IV drugs using sucrose acetate isobutyrate (SAIB). The drugs studied were rifaximin (RFX), dasatinib (DST), aripiprazole (APZ), dolutegravir (DLT), cyclosporine (CYS), itraconazole (ITZ), tacrolimus (TAC), sirolimus (SRL), aprepitant (APT), and carbamazepine (CBZ). AGSs were prepared by dissolving known quantity of the drug in the SAIB at 120 (TAC and APZ), 140 (CYS) or 150 oC (RFX, DST, DLT, ITZ, SRL, APT, and CBZ). They were characterized visually and by NIR, NIR hyperspectroscopy (NIR-H), and XRPD. Stability were determined by exposing open vials to 40 oC/75% RH for a week. AGSs behave like a glassy solid at room temperature and liquified above 60 oC. The solubility of APT, DLT, SRL, APZ, RFX, CBZ, TAC and CYS in SAIB was 0.4±0.0, 1.7±0.4, 1.9±0.0, 21.6±2.6, 36.4±0.9, 76.5±4.0, 115.1±2.3, and 239.0±12.6 mg/g, respectively. NIR, NIR-H, and XRPD data indicated the amorphous nature of the AGSs. Furthermore, AGSs were stable against devitrification on exposure to high temperature and humidity. In summary, SAIB can be employed to develop stable AGSs of poorly soluble drugs to increase dissolution, and oral bioavailability with the addition of hydrophilic excipients.


Assuntos
Excipientes , Itraconazol , Disponibilidade Biológica , Estabilidade de Medicamentos , Solubilidade , Difração de Raios X
12.
Biotechnol Bioeng ; 117(7): 2223-2236, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32333614

RESUMO

Medium-chain esters are versatile chemicals with broad applications as flavors, fragrances, solvents, and potential drop-in biofuels. Currently, these esters are largely produced by the conventional chemical process that uses harsh operating conditions and requires high energy input. Alternatively, the microbial conversion route has recently emerged as a promising platform for sustainable and renewable ester production. The ester biosynthesis pathways can utilize either lipases or alcohol acyltransferase (AAT), but the AAT-dependent pathway is more thermodynamically favorable in an aqueous fermentation environment. Even though a cellulolytic thermophile Clostridium thermocellum harboring an AAT-dependent pathway has recently been engineered for direct conversion of lignocellulosic biomass into esters, the production is not efficient. One potential bottleneck is the ester degradation caused by the endogenous carbohydrate esterases (CEs) whose functional roles are poorly understood. The challenge is to identify and disrupt CEs that can alleviate ester degradation while not negatively affecting the efficient and robust capability of C. thermocellum for lignocellulosic biomass deconstruction. In this study, by using bioinformatics, comparative genomics, and enzymatic analysis to screen a library of CEs, we identified and disrupted the two most critical CEs, Clo1313_0613 and Clo1313_0693, that significantly contribute to isobutyl acetate degradation in C. thermocellum. We demonstrated that an engineered esterase-deficient C. thermocellum strain not only reduced ester hydrolysis but also improved isobutyl acetate production while maintaining effective cellulose assimilation.


Assuntos
Acetatos/metabolismo , Proteínas de Bactérias/metabolismo , Celulose/metabolismo , Clostridium thermocellum/metabolismo , Esterases/metabolismo , Proteínas de Bactérias/genética , Celulose/genética , Clostridium thermocellum/genética , Esterases/genética , Microbiologia Industrial/métodos , Engenharia Metabólica/métodos
13.
Pharmacol Res ; 160: 105082, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32679183

RESUMO

BACKGROUND: Maternal diet plays a beneficial role in the health, including the neurodevelopment, of offspring. Insufficient fibre consumption among the general population has increased concern about neurocognitive diseases. However, the association between maternal low-fibre diet (MLFD) and neurocognitive function in offspring is still unclear. METHODS: Mice were fed diets containing diverse levels of fibre or administered short-chain fatty acids (SCFAs) during gestation. The neurocognitive functions of the offspring and synaptic plasticity-related protein levels were measured. Gene expression was disrupted by siRNA interference. Samples from pregnant women and paired umbilical cord blood (UCB) samples were analysed by the general linear model. RESULTS: We found that MLFD impaired cognitive function and synaptic plasticity in offspring and that the impairments were reversed by butyrate intake but not propionate intake. Mechanistic studies showed that histone deacetylase (HDAC)-4 is the most likely mediator of butyrate-dependent neurocognitive improvement. In addition, using human maternal serum and paired UCB samples, we demonstrated that SCFA levels in offspring were positively correlated with levels in the maternal serum. CONCLUSION: These results provide solid evidence that fibre in the maternal diet regulates neurocognitive functions in offspring through altering SCFA levels and supports the use of SCFA-dependent perinatal intervention for improving offspring health in the clinic.


Assuntos
Comportamento Animal/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Butiratos/farmacologia , Cognição/efeitos dos fármacos , Dieta/efeitos adversos , Inibidores de Histona Desacetilases/farmacologia , Histona Desacetilases/metabolismo , Transtornos Neurocognitivos/prevenção & controle , Efeitos Tardios da Exposição Pré-Natal , Adulto , Fenômenos Fisiológicos da Nutrição Animal , Animais , Encéfalo/enzimologia , Encéfalo/fisiopatologia , Fibras na Dieta/metabolismo , Modelos Animais de Doenças , Ácidos Graxos/sangue , Feminino , Microbioma Gastrointestinal , Humanos , Fenômenos Fisiológicos da Nutrição Materna , Camundongos Endogâmicos C57BL , Transtornos Neurocognitivos/enzimologia , Transtornos Neurocognitivos/etiologia , Transtornos Neurocognitivos/fisiopatologia , Plasticidade Neuronal/efeitos dos fármacos , Estado Nutricional , Valor Nutritivo , Gravidez , Propionatos/farmacologia
14.
Appl Microbiol Biotechnol ; 104(11): 5119-5131, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32248436

RESUMO

Isobutyrate (i-butyrate) is a versatile platform chemical, whose acid form is used as a precursor of plastic and emulsifier. It can be produced microbially either using genetically engineered organisms or via microbiomes, in the latter case starting from methanol and short-chain carboxylates. This opens the opportunity to produce i-butyrate from non-sterile feedstocks. Little is known on the ecology and process conditions leading to i-butyrate production. In this study, we steered i-butyrate production in a bioreactor fed with methanol and acetate under various conditions, achieving maximum i-butyrate productivity of 5.0 mM day-1, with a concurrent production of n-butyrate of 7.9 mM day-1. The production of i-butyrate was reversibly inhibited by methanogenic inhibitor 2-bromoethanesulfonate. The microbial community data revealed the co-dominance of two major OTUs during co-production of i-butyrate and n-butyrate in two distinctive phases throughout a period of 54 days and 28 days, respectively. The cross-comparison of product profile with microbial community composition suggests that the relative abundance of Clostridium sp. over Eubacterium sp. is correlated with i-butyrate productivity over n-butyrate productivity.


Assuntos
Butiratos/metabolismo , Clostridium/metabolismo , Eubacterium/metabolismo , Isobutiratos/metabolismo , Metanol/metabolismo , Microbiota , Reatores Biológicos , Clostridium/isolamento & purificação , Eubacterium/isolamento & purificação , Fermentação
15.
J Environ Manage ; 258: 110008, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31929052

RESUMO

Microbial chain elongation (MCE) is a bioprocess that could utilise a mixed-culture fermentation to valorise organic waste. MCE converting ethanol and short chain fatty acids (SCFA; derived from organic waste) to caproate has been studied extensively and implemented. Recent studies demonstrated the conversion of SCFAs and methanol or ethanol into isomerised fatty acids as novel products, which may expand the MCE application and market. Integrating caproate and isomerised fatty acid production in one reactor system is theoretically feasible given the employment of a mixed culture and may increase the economic competence of MCE; however, the feasibility of such has never been demonstrated. This study investigated the feasibility of using two electron donors, i.e. methanol and ethanol, for upgrading SCFAs into isobutyrate and caproate concurrently in MCE Results show that supplying methanol and ethanol in MCE simultaneously converted acetate and/or butyrate into caproate and isobutyrate, by a mixed-culture microbiome. The butyrate supplement stimulated the caproate production rate from 1.5 to 2.6 g/L.day and induced isobutyrate production (1.5 g/L.day). Further increasing ethanol feeding rate from 140 to 280 mmol carbon per litre per day enhanced the direct use of butyrate for caproate production, which improved the caproate production rate to 5.9 g/L.day. Overall, the integration of two electron donors, i.e. ethanol and methanol, in one chain-elongation reactor system for upgrading SCFAs was demonstrated. As such, MCE could be applied to valorise organic waste (water) streams into a wider variety of value-added biochemical.


Assuntos
Caproatos , Etanol , Ácidos Graxos , Ácidos Graxos Voláteis , Fermentação , Isobutiratos , Metanol
16.
AAPS PharmSciTech ; 21(3): 99, 2020 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-32133549

RESUMO

The objective of the present investigation was to understand the effect of sucrose acetate isobutyrate (SAIB) on abuse-deterrent properties (ADPs) of abuse-deterrent formulations (ADFs) based on Polyox™. SAIB would enhance ADPs of Polyox™-based formulations due to its glassy liquid and hydrophobic properties. Formulations were prepared by granulation followed by compression and heat curing at 90°C. The formulations were evaluated for surface morphology, hardness, manipulation in coffee grinder, particle size distribution, drug (pseudoephedrine hydrochloride) extraction in water, alcohol, 0.1 N HCl, 0.1 N NaOH at room temperature and elevated temperature using microwave and oven, syringeability and injectability, and dissolution. The heat curing of formulations significantly increased the hardness (> 490 N). Addition of SAIB imparted elasticity to formulations and decreased brittleness as indicated by lower values of work done and gradient compared to control formulations. After grinding, about 7.7-25.6% of the powder remained on the sieve (1 mm pore opening), D90 was 53.1-136.7 µm more, and Q (fraction < 500 µm) was 17.8-40.7% less in SAIB-based formulations compared to control formulations. Drug extraction between control and test intact formulations was similar. However, drug extraction was 23.9-42.5% (water), 20.6-26.1% (0.1 N HCl), and 37.4-50.6% (0.1 N NaOH) less in SAIB-based powder cured and uncured formulations compared to control formulations. Dissolution varied from 65.6 ± 4.2 to 97.6 ± 4.0% in 9 h from the formulations. In conclusion, addition of SAIB to Polyox™-based ADFs has synergistic effect on ADPs. This would further decrease potential of drug abuse/misuse by various routes.


Assuntos
Formulações de Dissuasão de Abuso/métodos , Composição de Medicamentos/métodos , Desenvolvimento de Medicamentos/métodos , Sacarose/análogos & derivados , Formulações de Dissuasão de Abuso/tendências , Composição de Medicamentos/tendências , Desenvolvimento de Medicamentos/tendências , Dureza , Transtornos Relacionados ao Uso de Opioides/tratamento farmacológico , Transtornos Relacionados ao Uso de Opioides/metabolismo , Tamanho da Partícula , Pós , Sacarose/administração & dosagem , Sacarose/química , Difração de Raios X/métodos , Difração de Raios X/tendências
17.
Microb Cell Fact ; 18(1): 60, 2019 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-30909908

RESUMO

BACKGROUND: Corynebacterium glutamicum is an important industrial strain for the production of a diverse range of chemicals. Cpf1 nucleases are highly specific and programmable, with efficiencies comparable to those of Cas9. Although the Francisella novicida (Fn) CRISPR-Cpf1 system has been adapted for genome editing in C. glutamicum, the editing efficiency is currently less than 15%, due to false positives caused by the poor targeting efficiency of the crRNA. RESULTS: To address this limitation, a screening strategy was developed in this study to systematically evaluate crRNA targeting efficiency in C. glutamicum. We quantitatively examined various parameters of the C. glutamicum CRISPR-Cpf1 system, including the protospacer adjacent motif (PAM) sequence, the length of the spacer sequence, and the type of repair template. We found that the most efficient C. glutamicum crRNA contained a 5'-NYTV-3' PAM and a 21 bp spacer sequence. Moreover, we observed that linear DNA could be used to repair double strand breaks. CONCLUSIONS: Here, we identified optimized PAM-related parameters for the CRISPR-Cpf1 system in C. glutamicum. Our study sheds light on the function of the FnCpf1 endonuclease and Cpf1-based genome editing. This optimized system, with higher editing efficiency, could be used to increase the production of bulk chemicals, such as isobutyrate, in C. glutamicum.


Assuntos
Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/genética , Corynebacterium glutamicum/enzimologia , Corynebacterium glutamicum/genética , RNA/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/fisiologia , Endonucleases/fisiologia , Edição de Genes
18.
J Chem Ecol ; 45(5-6): 455-463, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31140030

RESUMO

The spherical mealybug Nipaecoccus viridis is a pest of several major crops including soybeans, grapes and citrus varieties. Sessile virgin females of N. viridis release two volatiles, 2,2,3,4-tetramethyl-3-cyclopentene-1-methanol (γ-necrodol) and γ-necrodyl isobutyrate, on a circadian rhythm with peak at 17:00 (11 hr of photophase) as determined by automated, sequential solid phase micro extraction with gas chromatography-mass spectrometry analysis. The females increased the released amounts with age by about seven-fold from 5 to 6 d to 10-12 d of age. trans-3,4,5,5-Tetramethyl-2-cyclopentene-1-methanol (trans-α-necrodol) and trans-α-necrodyl acetate, found in essential oil of Spanish lavender, Lavandula luisieri, were rearranged to γ-necrodol and then used to synthesize γ-necrodyl isobutyrate. GC-MS and NMR data confirmed the identifications. In a petri dish bioassay, N. viridis males were significantly attracted to filter paper discs impregnated with γ-necrodyl isobutyrate but not to γ-necrodol or controls. A mixture of the two compounds was not more attractive than γ-necrodyl isobutyrate alone. Similar results were obtained with trapping flying adults, suggesting that the sex pheromone consists only of γ-necrodyl isobutyrate. This compound has not been reported previously in insects. Conversion of α-necrodol in lavender essential oil simplifies the synthesis of the sex pheromone and should allow its use in management of this cosmopolitan invasive pest.


Assuntos
Hemípteros/química , Atrativos Sexuais/química , Animais , Ciclopentanos/química , Ciclopentanos/isolamento & purificação , Ciclopentanos/farmacologia , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Hemípteros/fisiologia , Isomerismo , Espectroscopia de Ressonância Magnética , Masculino , Monoterpenos/química , Monoterpenos/isolamento & purificação , Monoterpenos/farmacologia , Atrativos Sexuais/isolamento & purificação , Atrativos Sexuais/farmacologia , Comportamento Sexual Animal/efeitos dos fármacos , Microextração em Fase Sólida
19.
Molecules ; 24(18)2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31527386

RESUMO

The two coordination compounds of cobalt were designed and synthesized. The substrates were carefully selected to allow gentle tuning of the molecular structure of the designed compounds. The crystal, molecular and supramolecular structure of studied compounds has been determined and discussed. The spectroscopic and thermal properties of designed coordination compounds have been studied and their application as precursors for the synthesis of cobalt oxide nanoparticles has been demonstrated. It was proven that not only are parameters of conversion of the precursor to nanoparticles important, but also small changes in molecular structure can considerably affect the size of formed particles. For unambiguous determination of the influence of compounds structure on their UV-Vis radiation absorption, density functional theory and time-dependent density functions theory calculations have been performed. The complexity of the correct ab-initio reflection of the open shell molecular system was outlined and discussed. The results obtained from density functional theory (DFT) calculations have been also employed for discussion of the bonding properties.


Assuntos
Cobalto/química , Complexos de Coordenação/química , Modelos Moleculares , Complexos de Coordenação/síntese química , Teoria da Densidade Funcional , Isomerismo , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Conformação Molecular , Estrutura Molecular , Óxidos/química , Análise Espectral
20.
J Anim Physiol Anim Nutr (Berl) ; 99(1): 123-131, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24702602

RESUMO

The objective of this study was to evaluate the effects of isobutyrate supplementation on rumen microflora, enzyme activities and methane emissions in Simmental steers consuming a corn stover-based diet. Eight ruminally cannulated Simmental steers were used in a replicated 4 × 4 Latin square experiment. The treatments were control (without isobutyrate), low isobutyrate (LIB), moderate isobutyrate (MIB) and high isobutyrate (HIB) with 8.4, 16.8 and 25.2 g isobutyrate per steer per day respectively. Isobutyrate was hand-mixed into the concentrate portion. Diet consisted of 60% corn stover and 40% concentrate [dry matter (DM) basis]. Dry matter intake (averaged 9 kg/day) was restricted to a maximum of 90% of ad libitum intake. Population of total bacteria, cellulolytic bacteria and anaerobic fungi were linearly increased, whereas that of protozoa and total methanogens was linearly reduced with increasing isobutyrate supplementation. Real-time PCR quantification of population of Ruminococcus albus, Ruminococcus flavefaciens, Butyrivibrio fibrisolvens and Fibrobacter succinogenes was linearly increased with increasing isobutyrate supplementation. Activities of carboxymethyl cellulase, xylanase and ß-glucosidase were linearly increased, whereas that of protease was linearly reduced. Methane production was linearly decreased with increasing isobutyrate supplementation. Effective degradabilities of cellulose and hemicellulose of corn stover were linearly increased, whereas that of crude protein in diet was linearly decreased with increasing isobutyrate supplementation. The present results indicate that isobutyrate supplemented improved microflora, rumen enzyme activities and methane emissions in steers. It was suggested that the isobutyrate stimulated the digestive micro-organisms or enzymes in a dose-dependent manner. In the experimental conditions of this trial, the optimum isobutyrate dose was approximately 16.8 g isobutyrate per steer per day.


Assuntos
Bovinos/fisiologia , Suplementos Nutricionais , Isobutiratos/farmacologia , Metano/metabolismo , Rúmen/microbiologia , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Dieta/veterinária , Relação Dose-Resposta a Droga , Isobutiratos/administração & dosagem , Masculino , Rúmen/enzimologia
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