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1.
BMC Complement Med Ther ; 22(1): 8, 2022 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-34991582

RESUMO

INTRODUCTION: The use of traditional medicinal plants in the management of diarrhea has long been practiced in Ethiopia. B. abyssinica fresen is one of the plants traditionally used to treat diarrhea whereas an in vivo study had not yet been conducted. Thus, this study aimed to evaluate the antidiarrheal activity of crude extract and solvent fractions of the leaf of B. abyssinica in mice. METHODS: Cold maceration within 80% methanol was used to extract the leaf powder and extract of the leaf was fractionated using n-hexane, chloroform, and distilled water. The in vivo antidiarrheal activity of crude extracts and solvent fractions were tested in experimental models of castor oil-induced diarrhea, enteropooling, and antimotility test. Five groups each with 6 mice were used under the three antidiarrheal models. Positive controls were treated with loperamide 3 mg/kg and atropine 5 mg/kg and 2% tween 80 was used in the treatment of negative controls. The extract and solvent fractions were administered at doses of 100, 200, and 400 mg/kg. Time of onset of diarrhea, number and weight of total and wet feces, the percent reduction in the number of wet feces, weight and volume of intestinal contents, and percent inhibition of intestinal motility were recorded. Data were analyzed using SPSS version 20. RESULT: Defecation of castor oil-induced diarrheal or loose stools was inhibited (p < 0.01 to p < 0.001) at 200 mg/kg and 400 mg/kg of crude extract and aqueous fraction. The crude extract and the aqueous fraction at three doses (p < 0.01 to p < 0.001), the chloroform fraction at 200 mg/kg and 400 mg/kg (p < 0.01 to p < 0.001), and the n-hexane fraction at 400 mg/kg (p < 0.05) reduced intraluminal fluid accumulation compared with the negative control. Castor oil-induced intestinal motility was significantly suppressed with the three-doses of aqueous fraction (p < 0.05 to p < 0.001), 200 mg/kg and 400 mg/kg of crude extract (p < 0.05 to p < 0.01), 400 mg/kg of chloroform and n-hexane (p < 0.01 to p < 0.001) compared with negative control. CONCLUSION: The crude extract, aqueous, and chloroform fractions of B. abyyssinica leaves have promising anti-diarrheal effects, supporting the plant's traditional use to treat diarrhea.


Assuntos
Antidiarreicos/uso terapêutico , Diarreia/tratamento farmacológico , Magnoliopsida , Fitoterapia , Extratos Vegetais/uso terapêutico , Animais , Antidiarreicos/farmacologia , Óleo de Rícino , Clorofórmio , Defecação/efeitos dos fármacos , Diarreia/induzido quimicamente , Etiópia , Fezes , Motilidade Gastrointestinal/efeitos dos fármacos , Intestinos/efeitos dos fármacos , Medicina Tradicional Africana , Metanol , Camundongos , Extratos Vegetais/farmacologia , Folhas de Planta , Distribuição Aleatória , Solventes
2.
J Mol Graph Model ; 110: 108048, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34656942

RESUMO

Due to the importance of synthesis gas's entire conversion to methanol, the separation of methanol from unconverted synthesis gas is an industrial challenge. In this work, the influence of temperature, guest molecules concentrations (methanol and ethanol), and acid site density (Si/Al) of zeolites on the diffusion of methanol and ethanol, pure and binary mixture (80% methanol and 20% ethanol) in silicalite-1 and HZSM-5 (Si/Al = 47 and 23) were studied by using of the COMPASS force-field molecular dynamics method. Also, the adsorption of pure methanol and ethanol and binary mixture through these zeolites has been studied by using the Grand Canonical Monte Carlo (GCMC) method. The calculated adsorption rate and isosteric heat of adsorption for ethanol are lower and higher than methanol, respectively. The results of the binary mixture show that HZSM-5 (Si/Al = 23) has the lowest adsorption selectivity and most diffusion selectivity. The calculated diffusion coefficients of methanol and ethanol guest molecules decreased with rising guest molecule concentration and Si/Al-ratios. The effect of both agents was investigated by analysis of mean square displacement (MSD) and RDF diagram.


Assuntos
Zeolitas , Adsorção , Etanol , Metanol , Simulação de Dinâmica Molecular
3.
J Sci Food Agric ; 102(1): 425-433, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34143901

RESUMO

BACKGROUND: Apple wine is a popular alcoholic beverage for its nutrition and fresh taste. However, the methanol existing in apple wine restricts its quality. Unfortunately, there are no methods to reduce the methanol content in fruit wine. To this end, bentonite (B), calcium chloride (CC) and their combination (B&CC) were added into apple juice in this study. The treated juice (0) and supernatant obtained by standing the juice at 25 °C for 24 h were fermented at 25 °C and 10 °C, respectively. RESULTS: Bentonite was an excellent methanol interrupter, a pectin retainer and a wine quality defender both at 25 and 10 °C. The lowest methanol content of 1.41 mg L-1 and higher pectin content of 84.74 mg L-1 were reached in the finished wine by B0 at 10 °C. Calcium chloride decreased pectin content, elevated methanol content and changed the profile of individual organic acids. In fact, the wine by B&CC0 at 25 °C showed dramatic changes in individual organic acids. The content of l-malic acid and succinic acid was only 2.22% and 6.29% of the control, respectively, while the lactic acid content was 17.72 times that of the control. CONCLUSIONS: It is suggested that B0 and fermented at 10 °C was the most effective way to decrease methanol content, retain pectin content and defend wine quality. © 2021 Society of Chemical Industry.


Assuntos
Bebidas Alcoólicas/análise , Bentonita/química , Cloreto de Cálcio/química , Manipulação de Alimentos/métodos , Malus/química , Fermentação , Manipulação de Alimentos/instrumentação , Frutas/química , Metanol/química , Pectinas/química
4.
J Colloid Interface Sci ; 605: 354-363, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34332409

RESUMO

HYPOTHESIS: Organic co-solvents, which are universally employed in adsorption studies of hydrophobic organic chemicals (HOCs), can inhibit HOC adsorption by competing for active sites on the adsorbent. The adsorbent structure can influence co-solvent interference of HOC adsorption; however, this effect remains unclear, leading to an incomplete understanding of the adsorption mechanism. EXPERIMENTS: In this study, dioctyl phthalate (DOP) was used to investigate competitive adsorption on functionalized graphene sheet in a water-methanol co-solvent system through molecular dynamics simulations and quantum chemical calculations. FINDINGS: The simulations showed that the functional groups in the graphene defects had a strong adsorption affinity for methanol. The adsorbed methanol occupied a large number of active sites at the graphene center, thereby weakening DOP adsorption. However, the methanol adsorbed at the graphene edges could not compete with DOP for the active sites. -COOH had the strongest binding affinity for methanol among the functional groups and thus predominantly controlled the interaction between graphene and methanol. This study makes an innovative contribution toward understanding the competitive adsorption of methanol and DOP on functionalized graphene sheet, especially in visualizing the competition for active sites, and provides theoretical guidance for the removal of HOCs and practical application of graphene.


Assuntos
Dietilexilftalato , Grafite , Adsorção , Metanol , Simulação de Dinâmica Molecular , Solventes
5.
Food Chem ; 372: 131272, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-34628121

RESUMO

Bioactive compounds from strawberries have been associated with multiple healthy benefits. The present study aimed to assess chemical characterization of a methanolic extract of the Romina strawberry variety in terms of antioxidant capacity, polyphenols profile and chemical elements content. Additionally, potential toxicity, the effect on amyloid-ß production and oxidative stress of the extract was in vivo evaluated in the experimental model Caenorhabditis elegans. Results revealed an important content in phenolic compounds (mainly ellagic acid and pelargonidin-3-glucoside) and minerals (K, Mg, P and Ca). The treatment with 100, 500 or 1000 µg/mL of strawberry extract did not show toxicity. On the contrary, the extract was able to delay amyloid ß-protein induced paralysis, reduced amyloid-ß aggregation and prevented oxidative stress. The potential molecular mechanisms present behind the observed results explored by RNAi technology revealed that DAF-16/FOXO and SKN-1/NRF2 signaling pathways were, at least partially, involved.


Assuntos
Doença de Alzheimer , Proteínas de Caenorhabditis elegans , Fragaria , Peptídeos beta-Amiloides/genética , Animais , Antioxidantes , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Ligação a DNA/metabolismo , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/metabolismo , Fragaria/genética , Fragaria/metabolismo , Metanol , Estresse Oxidativo , Extratos Vegetais , Fatores de Transcrição/metabolismo
6.
J Environ Manage ; 301: 113927, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34638043

RESUMO

The study demonstrates a two-stage integrated process for bio-methanol production using Methylosinus trichosporium NCIMB 11131, coupled with sequestration of methane and carbon dioxide. The first stage involved generation of methanotrophic biomass via sequestration of methane; which was used as biocatalyst to reduce carbon dioxide into methanol in the second stage. Maximum biomass titer of 3.39 g L-1 and productivity of 0.60 g L-1 d-1 were achieved in semi-batch stirred tank reactor with methane concentration in the inlet gas mixture of 2.5% v/v and gas flow rate of 0.5 vvm. Methane fixation rate was estimated to be 0.32 g L-1 d-1. Maximum methanol titer of 0.58 g L-1 was achieved at headspace carbon dioxide concentration of 50% v/v and liquid to headspace volume ratio 10:90. Subsequently, a kinetic model was developed to predict and understand the system behaviour in terms of dynamic profile of growth, methanol formation, concentration of dissolved methane or carbon dioxide in the aqueous phase and headspace carbon dioxide concentration, in response to varying process parameters. The model can serve as a tool for estimation of process parameters and aid in overall production optimization.


Assuntos
Metano , Methylosinus trichosporium , Biomassa , Dióxido de Carbono , Metanol
7.
Talanta ; 237: 122888, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34736708

RESUMO

In this work, based on the dual catalytic properties of copper (Cu) particles for methanol oxidation and persulfate initiated radical polymerization, a temperature-controlled catalytic electrode, defined the PNIPAM-Cu@CP, was constructed by electrodepositing Cu particles on a carbon paper electrode and triggering the polymerization of the temperature-sensitive polymer N-isopropylacrylamide (PNIPAM) on the surface of the electrode, which is expected to be applicated in the micro-direct methanol fuel cell (DMAC) for detection of methanol crossover and also has temperature recognition and high-temperature self-protection functions. Cu particles and PNIPAM were characterized by X-ray diffraction (XRD), fourier-transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM) for their specific structure and morphology. The cyclic voltammetry (CV) results showed the proposed electrode as a temperature-controlled switch-like methanol sensor, has a wide linear range (1-300 mM and 300-1200 mM), excellent sensitivity (72.8 µA cm-2 mM-1 and 11.5 µA cm-2 mM-1) and a low detection limit of 0.3 mM for methanol. In addition, the sensor also has excellent selectivity and temperature-triggered switchable electrocatalytic activity. The efficient and simple preparation method of the electrode is expected to be used in the development of a methanol sensor for real-time methanol detection in micro-DMAC.


Assuntos
Cobre , Metanol , Catálise , Técnicas Eletroquímicas , Eletrodos , Limite de Detecção , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura
8.
J Biotechnol ; 343: 128-137, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34906603

RESUMO

Methanol is a promising green feedstock for producing fuels and chemicals because it is inexpensive, clean, environmentally friendly, and easily prepared. Thus, many studies have been devoted to engineering non-native methylotrophic platform microorganisms to utilize methanol. This study adopted a series of strategies to develop a synthetic methylotrophic Bacillus subtilis that can use methanol as the carbon source, including the heterologous expression of methanol dehydrogenase (Mdh), enhancement of the expressions of 3-hexulose-6-phosphate synthase (Hps) and 6-phospho-3-hexuloisomerase (Phi), regulation of the expressions of key enzymes at both the translational and transcriptional levels, stabilization of the key enzyme expression through a dual-system for expressing the target genes on both the plasmid and genome, and improvement of the catalytic activity of Mdh with a recycling strategy for NAD+. As a result, the methanol consumption of the synthetic methylotrophic B. subtilis reached 4.09 g/L, with the maximum OD600 showing a 2.21-fold increase compared with the wild-type B. subtilis, which cannot use methanol. We further deleted the phosphoglucose isomerase (Pgi) and added co-substrates to increase the supply of ribulose-5-phosphate (Ru-5-P), and the specific methanol consumption rate increased by an additional 27.54%. Finally, we successfully constructed two strains that cannot grow in M9 medium with xylose or ribose unless methanol is utilized. The strategies used in this study are generally applicable to other studies on synthetic methylotrophy.


Assuntos
Bacillus , Metanol , Bacillus/genética , Bacillus subtilis/genética , Engenharia Metabólica , Plasmídeos
9.
Sci Total Environ ; 804: 150236, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34520913

RESUMO

Renewable energy sources for harnessing biofuels are the viable solution to substitute fossil fuels and reduce production cost. In this study, waste cooking oil was converted into biodiesel via a customized solar reactor. The solar reactor was customized using copper tubes and black surface to trap solar energy for conversion of waste cooking oil into biodiesel. The main experimental parameters studied are temperature (30 to 50 °C), stirring speed (100 to 500 rpm), catalyst loading (0.25 to 1.25 wt%), flow rate (3 to 15 LPH), and methanol to oil ratio (3:1 to 15:1), respectively. The uppermost conversion of 82% was achieved at catalyst load of 0.75 wt%, stirring speed of 300 rpm, flow rate of 3 LPH and methanol/oil ratio of 12:1. Performance of biodiesel blend (D80 + BD20) in CI engine showed a decrease in ignition delay (10.5 deg. CA) and brake thermal efficiency (32.7%) at maximum load (100%). Smoke emission was also decreased with an increase in biodiesel blend at lower brake power, but an increase in brake power increased the smoke emission.


Assuntos
Biocombustíveis , Culinária , Biocombustíveis/análise , Catálise , Metanol , Óleos Vegetais , Emissões de Veículos
10.
Appl Microbiol Biotechnol ; 105(23): 8761-8769, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34748038

RESUMO

Promoters play an important role in regulating gene expression, and construction of microbial cell factories requires multiple promoters for balancing the metabolic pathways. However, there are only a limited number of characterized promoters for gene expression in the methylotrophic yeast Ogataea polymorpha, which hampers the extensive harnessing of this important yeast toward a cell factory. Here we characterized the promoters of methanol utilization pathway, precursor supply pathway, and reactive oxygen species (ROS) defense system, by using a green fluorescence protein variant (GFPUV) as a quantification signal. Finally, the characterized promoters were used for tuning a fatty alcohol biosynthetic pathway in O. polymorpha and realized fatty alcohol production from methanol. This promoter box should be helpful for gene expression and pathway optimization in the methylotrophic yeast O. polymorpha. KEY POINTS : • 22 promoters related to methanol metabolism were characterized in O. polymorpha. • Promoter truncation resulted shorter and compact promoters. • Promoters with various strengths were used for regulating a fatty alcohol biosynthesis from methanol.


Assuntos
Engenharia Metabólica , Metanol , Pichia/genética , Regiões Promotoras Genéticas , Saccharomycetales
11.
Molecules ; 26(21)2021 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-34771068

RESUMO

Caragana rosea Turcz, which belongs to the Leguminosae family, is a small shrub found in Northern and Eastern China that is known to possess anti-inflammatory properties and is used to treat fever, asthma, and cough. However, the underlying molecular mechanisms of its anti-inflammatory effects are unknown. Therefore, we used lipopolysaccharide (LPS) in RAW264.7 macrophages to investigate the molecular mechanisms that underlie the anti-inflammatory activities of a methanol extract of Caragana rosea (Cr-ME). We showed that Cr-ME reduced the production of nitric oxide (NO) and mRNA levels of iNOS, TNF-α, and IL-6 in a concentration-dependent manner. We also found that Cr-ME blocked MyD88- and TBK1-induced NF-κB and IRF3 promoter activity, suggesting that it affects multiple targets. Moreover, Cr-ME reduced the phosphorylation levels of IκBα, IKKα/ß and IRF3 in a time-dependent manner and regulated the upstream NF-κB proteins Syk and Src, and the IRF3 protein TBK1. Upon overexpression of Src and TBK1, Cr-ME stimulation attenuated the phosphorylation of the NF-κB subunits p50 and p65 and IRF3 signaling. Together, our results suggest that the anti-inflammatory activity of Cr-ME occurs by inhibiting the NF-κB and IRF3 signaling pathways.


Assuntos
Anti-Inflamatórios/farmacologia , Caragana/química , Inflamação/tratamento farmacológico , Metanol/química , Extratos Vegetais/farmacologia , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Células Cultivadas , Células HEK293 , Humanos , Inflamação/induzido quimicamente , Inflamação/metabolismo , Fator Regulador 3 de Interferon/antagonistas & inibidores , Fator Regulador 3 de Interferon/metabolismo , Lipopolissacarídeos/antagonistas & inibidores , Camundongos , NF-kappa B/antagonistas & inibidores , NF-kappa B/metabolismo , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Células RAW 264.7 , Transdução de Sinais/efeitos dos fármacos , Receptor 4 Toll-Like/antagonistas & inibidores , Receptor 4 Toll-Like/metabolismo
12.
Braz J Biol ; 83: e243332, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34730611

RESUMO

The present study was aimed to manifest the antibacterial and antifungal activity of methanolic extracts of Salix alba L. against seven Gram-positive and Gram-negative bacterial pathogens e.g. Streptococcus pyogenes, Staphylococcus aureus (1), S. aureus (2), Shigella sonnei, Escherichia coli (1), E. coli (2) and Neisseria gonorrhoeae and three fungal isolates from the air such as Aspergillus terreus, A. ornatus, and Rhizopus stolonifer. Two different serotypes of S. aureus and E. coli were used. The agar well-diffusion method results showed the dose-dependent response of plant extracts against bacterial and fungal strains while some organisms were found resistant e.g. E. coli (1), S. sonnei, A. terreus and R. stolonifer. The highest antibacterial activity was recorded at 17.000±1.732 mm from 100 mg/mL of leaves methanolic extracts against S. pyogenes while the activity of most of the pathogens decreased after 24 h of incubation. The highest antifungal activity was reported at 11.833±1.0 mm against A. ornatus at 50 mg/mL after 48 h of the incubation period. These experimental findings endorse the use of S. alba in ethnopharmacological formulations and suggest the use of methanolic extracts of the said plant to develop drugs to control the proliferation of resistant disease causing pathogenic microbes.


Assuntos
Antifúngicos , Salix , Antibacterianos/farmacologia , Antifúngicos/farmacologia , Aspergillus , Escherichia coli , Metanol , Testes de Sensibilidade Microbiana , Extratos Vegetais/farmacologia , Rhizopus , Staphylococcus aureus
13.
Washington, D.C.; OPS; 2021-11-04. (OPS/NMH/MH/21-0034).
em Espanhol | PAHO-IRIS | ID: phr-55111

RESUMO

Esta hoja informativa ofrece información sobre el alcohol no registrado, es decir, el que no se contabiliza en los sistemas oficiales del gobierno y suele producirse, distribuirse y venderse fuera de los canales formales bajo control gubernamental. En ella se describen los tipos de alcohol no registrado y los peligros para la salud asociados a su consumo, y se ofrecen recomendaciones para los consumidores sobre los productos alcohólicos no comerciales y para los gobiernos sobre la regulación del alcohol no registrado.


Assuntos
Alcoolismo , Bebidas Alcoólicas , Regulamentação Governamental , Alimentos e Bebidas Fermentados , Etanol , Metanol , Transtornos Relacionados ao Uso de Álcool , Antissépticos Bucais , Higienizadores de Mão , Cegueira , Morte , América
14.
Washington, D.C.; PAHO; 2021-11-04. (PAHO/NMH/MH/21-0034).
em Inglês | PAHO-IRIS | ID: phr-55110

RESUMO

This fact sheet provides information on unrecorded alcohol. Unrecorded alcohol is alcohol that is not accounted for by official government systems and is usually produced, distributed, and sold outside the formal channels under government control. The fact sheet outlines the types of unrecorded alcohol and the dangers to health associated with its consumption. It also provides recommendations for consumers on non-commercial alcohol products and for governments on the regulation of unrecorded alcohol.


Assuntos
Consumo de Bebidas Alcoólicas , Bebidas Alcoólicas , Regulamentação Governamental , Alimentos e Bebidas Fermentados , Etanol , Antissépticos Bucais , Higienizadores de Mão , Transtornos Relacionados ao Uso de Álcool , Metanol , Cegueira , Morte
15.
Toxicon ; 203: 40-50, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34610271

RESUMO

Moringa stenopetala (Baker f.) Cuf.and other Moringa species have traditionally been used to treat various diseases. The purpose of this study was to determine the cytotoxic and genotoxic effects of the methanolic extract of M. stenopetala leaf and its fractions on selected tumor cells. Cytotoxicity was determined by MTT assay. The comet assay was used toassess DNA damage, and gel electrophoresis was used to determine DNA fragmentation. Gene expression was analyzed by qPCR using two specific genes for each cancer cell line. Fractionation of the methanolic extract (E-1) on Diaion HP-20 yielded five fractions (Fr-2 to Fr-6); only Fr-4 and Fr-6 were cytotoxic to breast cancer cells (MCF-7; IC50 = 58.3 ± 0.93 and 35.8 ± 2.44 µg/mL, respectively), human hepatocellular carcinoma cells (HepG2; IC50 = 57.8 ± 1.57 and 39.3 ± 1.90 µg/mL, respectively), and Fr-4 was cytotoxic to human colon cancer cells (HCT-116; IC50 = 94.2 ± 4.9 µg/mL). In addition, exposure of the cancer cells to Fr-4 and Fr-6 resulted in a high level of DNA damage. Moreover, relative expression of MTAP and CDKN2A in MCF-7 were increased, whereas expression of p21 and p53 in HCT-116, and APC and TERT in HepG2 were decreased, similar to that of doxorubicin. LC-qTOF-MS was used to identify metabolites in E-1, the majority of which were enriched in Fr-4. Two terpenes (loliolide and dihydroactinidiolide), the majority of the flavonoids, and niazirin were about two fold enriched in Fr-4, whereas the majority of the lipids were 4-10 fold enriched. However, Fr-6 hardly showed compounds other than the two terpenes that were enriched 1.5 and 7 fold. The findings suggest that Fr-4 and Fr-6 are promising sources of compounds possessing cytotoxic and genotoxic properties.


Assuntos
Moringa , Dano ao DNA , Expressão Gênica , Humanos , Metaboloma , Metanol , Extratos Vegetais/farmacologia , Folhas de Planta
16.
J Chromatogr A ; 1657: 462583, 2021 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-34624711

RESUMO

Counter-current chromatography (CCC) is a widely used liquid-liquid separation technique. Much work has been performed to improve the retention of stationary phases and throughput. In previous research, high aspect ratio rectangular horizontal (RH) tubing has been proven to be able to improve resolution and throughput in comparison with standard circular (SC) tubing. However, those modifications and improvements of tubing shapes have only been tested on analytical tubing thus far. This study aims to verify whether RH tubing could achieve similar high stationary phase retention (Sf) and throughput on a semi-preparative CCC apparatus. First, a lighter and larger volume semi-preparative bobbin with thin-wall RH tubing was successfully manufactured. Then the Sf of this bobbin was tested with n-hexane-ethyl acetate-methanol-water (HEMWat) and dichloromethane-methanol-water (DMW) solvent systems, and its maximum throughput was explored with the mixture of Magnolia officinalis Rehd. Et Wils. The results show that the thin-wall RH tubing bobbin can retain high Sf for these solvent systems, even at a relatively high mobile phase flow rate, which is consistent with the analytical bobbin results. The throughput test demonstrates that 2.12 × throughput can be obtained with the RH tubing column bobbin compared to the conventional SC tubing column bobbin without changing the outside dimensions of the bobbin. The present study is a necessary step for the application of the RH tubing bobbin from a laboratory analytical scale to preparative industrial scale.


Assuntos
Distribuição Contracorrente , Magnolia , Cromatografia Líquida de Alta Pressão , Metanol , Solventes , Água
17.
J Chromatogr A ; 1657: 462586, 2021 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-34689906

RESUMO

Coumarin is a phytotoxin found in the popular spice cinnamon, which is used to flavor many Asian curry dishes. In this work, we developed and compared the analytical performance of reversed-phase liquid chromatography (RP-LC) and sweeping-micellar electrokinetic chromatography (MEKC) methods for the determination of coumarin in complex curry (gravy) samples. Using a matrix matched sample (curry after solvent extraction with methanol and diluted with 100 mM phosphoric acid), the intra-day and inter-day repeatability of retention/migration time and (corrected) peak area for both methods were acceptable (%RSD (n=6) ≤ 5%). The linear range and limit of quantitation (LOQ) were an order of magnitude better in RP-LC (RP-LC linear range = 0.11-108 mg/kg, LOQ = 0.11 mg/kg) (Sweeping-MEKC linear range = 2.16-216 mg/kg, LOQ = 2.16 mg/kg). However, the limit of detection (S/N=3) and LOQ in sweeping-MEKC was 0.65 mg/kg and 2.16 mg/kg, which were sufficient to report the levels of coumarin ≥ the European limit of 2 mg/kg in foods. During the analysis of 25 curry samples, relatively similar results for sweeping-MEKC and RP-LC were obtained for 6 samples that contained coumarin >LOQ of sweeping-MEKC. Interferences in RP-LC lead to significant overestimation of coumarin levels in 3 samples. Coumarin levels above the EU limit was found in 6 curry samples using the more selective sweeping-MEKC. This work should also raise public awareness on the presence of potentially high levels of coumarin in some foods.


Assuntos
Cromatografia Capilar Eletrocinética Micelar , Cromatografia de Fase Reversa , Cumarínicos , Metanol , Micelas
18.
J Chromatogr A ; 1658: 462631, 2021 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-34700137

RESUMO

A method to analyse short-chain bioactive peptides (MW < 800 Da) and their impurities was developed with a unified chromatography (UC) analysis, including a wide mobile phase gradient ranging from supercritical fluid to near-liquid conditions, with UV and electrospray ionization mass spectrometry detection (ESI-MS). Four stationary phases and three mobile phase compositions were examined. Ten model peptides were first selected to identify the best operating conditions, including five linear tripeptides and five cyclic pentapeptides, with log P values ranging from -5.9 to 3.6, and including isomeric species. Derringer desirability functions were designed to identify optimal operating conditions based on 7 criteria, namely the number of peaks detected (including all impurities resolved), the proportion of the chromatogram occupied by target peaks, the least favourable resolution observed between the main peptide and impurities, peak shape features (asymmetry and peak width at half height), and finally the signal-to-noise ratio observed both with UV (210 nm) and ESI-MS in positive ionization mode. The optimum conditions were obtained on Ascentis Express OH5 stationary phase, with a mobile phase composed of carbon dioxide and methanol, comprising 2% water and 20 mM ammonium hydroxide. The final gradient program ranged from 5 to 80% co-solvent in CO2, with a reversed flow rate gradient ranging from 3.0 to 1.5 mL/min. Back-pressure was set at 120 bar and the column oven temperature at 60°C. Optimal conditions were applied to a large set of 76 peptides (34 linear tripeptides and 42 cyclic pentapeptides) and provided adequate scattering of the peaks in the retention space, together with some separation of isomeric species, particularly for the cyclic peptides.


Assuntos
Cromatografia com Fluido Supercrítico , Espectrometria de Massas por Ionização por Electrospray , Metanol , Peptídeos , Solventes
19.
Phytomedicine ; 93: 153771, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34700271

RESUMO

BACKGROUND: Moringa oleifera Lam (MO) is native to India and is a cash crop widely cultivated in tropical and sub-tropical areas. The health improving properties of MO has been studied from a long time ago for the numerous phenolic compounds, including vitamins, flavonoids, phenolic acids, isothiocyanates, tannins and saponins, which are present in considerable amounts in the plant. A growing spectrum of therapeutic characteristics of MO leaves has been found and used in the remission or treatment of oxidative stress, liver disease, neurological disease, hyperglycemia and cancer. HYPOTHESIS: This review focused on researches applying MO or MO leaf extract as a functional food or cure against various disease and cellular injuries. We believed it would help the discovery of therapeutic application of MO and understanding of MO phytochemistry. METHODS: The data collected in this review were extracted from researches indexed in Web of Science, google scholar, PubMed, Science Direct and Scopus to find out health benefits and biological activities of MO leaves polyphenols. The studies reporting mechanistic route of phenolic compounds of MO leaves were also considered in the present study. RESULTS: It has been reported that polyphenols of MO leaf have protective characteristics against neurodegenerative disorders through reducing DNA damage, activation of AchE activity and inhibition of caspase-3 activity. It has been reported that, they protected the kidney from damage caused by melamine through suppressed the pro-inflammatory cytokine, metallopeptidase inhibitor 1 (TIMP-1), and kidney injury molecule 1 (KIM-1). Similarly, methanol extract of MO leaves has low hypoglycemic attributes and attenuate the risk of diabetes caused by alloxan by enhancing lipid metabolism and stimulating insulin release, glucose uptake, and glycogen synthesis. In addition, MO leaves are becoming the best phytomedicine to reduce hypertension, which are naturally known as angiotensin-1converting enzyme (ACE), acetylcholinesterase, arginase and phosphodiesterase 5 (PDE5) inhibitors. CONCLUSION: MO leaves extract as a health promoting food additives for human and animals due to its great protective effect against many diseases and the widely persistent environmental toxins which disrupted cellular metabolic function. More studies are required to use the phenolic compounds of MO leaves to develop and produce drugs for controlling and treatment of various diseases.


Assuntos
Moringa oleifera , Acetilcolinesterase , Animais , Antioxidantes/farmacologia , Humanos , Metanol , Fenóis/farmacologia , Extratos Vegetais/farmacologia , Folhas de Planta
20.
Chin J Physiol ; 64(5): 232-243, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34708715

RESUMO

Macrophages are essential for host defense as they control foreign pathogens and induce acquired immune responses. Activated macrophages secrete pro-inflammatory reactive substances causing local cell and tissue inflammatory response, which helps an organism resist the invasion of foreign pathogens. Excessive or chronic inflammation can cause several diseases. Previous studies have reported that vinegar treatment decreases the levels of several inflammatory cytokines and biomarkers, including mitogen-activated protein kinases, cyclooxygenase-2, inducible nitric oxide synthase (iNOS), and nitric oxide (NO). However, the benefits of wood vinegar produced from Griffith's ash (Fraxinus formosana Hayata) in reducing inflammation have not been investigated yet. Thus, assuming that wood vinegar exerts anti-inflammatory effects in macrophages, in this study, we investigated the potential anti-inflammatory effects of the wood vinegar from Griffith's ash using a lipopolysaccharide (LPS)-induced inflammatory response model in RAW264.7 macrophages. We showed that the wood vinegar inhibited the production of iNOS, NO, and interleukin 6. In addition, we found that the wood vinegar reduced the phosphorylation levels of p38 and protein kinase C-α/δ in the LPS-stimulated RAW264.7 macrophages. Based on these results, we suggest that the produced wood vinegar can reduce inflammation in LPS-activated macrophages.


Assuntos
Ácido Acético , Anti-Inflamatórios , Macrófagos/efeitos dos fármacos , Ácido Acético/farmacologia , Animais , Anti-Inflamatórios/farmacologia , Ciclo-Oxigenase 2 , Fraxinus , Inflamação/tratamento farmacológico , Mediadores da Inflamação , Lipopolissacarídeos , Metanol , Camundongos , NF-kappa B/metabolismo , Óxido Nítrico , Óxido Nítrico Sintase Tipo II , Células RAW 264.7
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