Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 45
Filtrar
1.
Crit Rev Food Sci Nutr ; : 1-15, 2023 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-37574586

RESUMO

Functional foods and their by-products contain a wide range of bioactive components with an array of health benefits and were proposed to improve public health, well-being, and others. To achieve a circular economy, the processing and extraction of flavonoids, phenolic compounds, and others from functional food and agri-food wastes will require the use of environmentally friendly, sustainable, and a low-cost solution. Extraction methods that can eliminate the use of organic solvents, suitable for use in the laboratory and production of extracts will be covered. This will include subcritical water extraction (SBE), pressurized hot water extraction (PHWE), supercritical fluid extraction (SFE), and others. Based on the selected analytical methods, the determination of the marker or bioactive compounds and chemical fingerprints will provide the control measures to identify the batch-to-batch variation of the composition of the functional food products obtained. The combination of chemical standardization with antioxidant assay, such as DPPH and ABTS+ will provide further information on the quality of the extracts. Lastly, to ascertain the biological and physiological relevance of the antioxidant properties of the target sample, treatment of the antioxidant compounds or extracts was carried out using cellular models, and validated using other experimental endpoints, such as metabolomics.

2.
Int J Mol Sci ; 24(11)2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37298458

RESUMO

Small molecules play an important role in extracting energy from cells, synthesising new macromolecules, and indicating metabolic shift and other processes (Figure 1) [...].

3.
Crit Rev Anal Chem ; : 1-16, 2023 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-37454386

RESUMO

Bioactive compounds in functional foods, medicinal plants and others are considered attractive value-added molecules based on their wide range of bioactivity. It is clear that an important role is occupied by polyphenol, phenolic compounds and others. Urine is an effective biofluid to evaluate and monitor alterations in homeostasis and other processes related to metabolism. The current review provides a detailed description of the formation of urine in human body, various aspects relevant to sampling and analysis of urinary metabolites before presenting recent developments leveraging on metabolite profiling of urine. For the profiling of small molecules in urine, advancement of liquid chromatography mass tandem spectrometry (LC/MS/MS), establishment of standardized chemical fragmentation libraries, computational resources, data-analysis approaches with pattern recognition tools have made it an attractive option. The profiling of urinary metabolites gives an overview of the biomarkers associated with the diet and evaluates its biological effects. Metabolic pathways such as glycolysis, tricarboxylic acid cycle, amino acid metabolism, energy metabolism, purine metabolism and others can be evaluated. Finally, a combination of metabolite profiling with chemical standardization and bioassay in functional food and medicinal plants will likely lead to the identification of new biomarkers and novel biochemical insights.

4.
Biomed Pharmacother ; 162: 114578, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36996678

RESUMO

BACKGROUND: The peptide hormone relaxin has potent anti-fibrotic and anti-inflammatory properties in various organs, including the kidneys. However, the protective effects of relaxin in the context of diabetic kidney complications remain controversial. Here, we aimed to evaluate the effects of relaxin treatment on key markers of kidney fibrosis, oxidative stress, and inflammation and their subsequent impact on bile acid metabolism in the streptozotocin-induced diabetes mouse model. METHODS AND RESULTS: Male mice were randomly allocated to placebo-treated control, placebo-treated diabetes or relaxin-treated diabetes groups (0.5 mg/kg/d, final 2 weeks of diabetes). After 12 weeks of diabetes or sham, the kidney cortex was harvested for metabolomic and gene expression analyses. Diabetic mice exhibited significant hyperglycaemia and increased circulating levels of creatine, hypoxanthine and trimethylamine N-oxide in the plasma. This was accompanied by increased expression of key markers of oxidative stress (Txnip), inflammation (Ccl2 and Il6) and fibrosis (Col1a1, Mmp2 and Fn1) in the diabetic kidney cortex. Relaxin treatment for the final 2 weeks of diabetes significantly reduced these key markers of renal fibrosis, inflammation, and oxidative stress in diabetic mice. Furthermore, relaxin treatment significantly increased the levels of bile acid metabolites, deoxycholic acid and sodium glycodeoxycholic acid, which may in part contribute to the renoprotective action of relaxin in diabetes. CONCLUSION: In summary, this study shows the therapeutic potential of relaxin and that it may be used as an adjunctive treatment for diabetic kidney complications.


Assuntos
Diabetes Mellitus Experimental , Nefropatias Diabéticas , Relaxina , Animais , Camundongos , Masculino , Nefropatias Diabéticas/tratamento farmacológico , Diabetes Mellitus Experimental/tratamento farmacológico , Relaxina/farmacologia , Estreptozocina/farmacologia , Rim , Estresse Oxidativo , Inflamação/tratamento farmacológico , Fibrose
5.
Sci Rep ; 13(1): 20303, 2023 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-37985702

RESUMO

Endothelial dysfunction is a critical initiating factor contributing to cardiovascular diseases, involving the gut microbiome-derived metabolite trimethylamine N-oxide (TMAO). This study aims to clarify the time-dependent molecular pathways by which TMAO mediates endothelial dysfunction through transcriptomics and metabolomics analyses in human microvascular endothelial cells (HMEC-1). Cell viability and reactive oxygen species (ROS) generation were also evaluated. TMAO treatment for either 24H or 48H induces reduced cell viability and enhanced oxidative stress. Interestingly, the molecular signatures were distinct between the two time-points. Specifically, few Gene Ontology biological processes (BPs) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways were modulated after a short (24H) compared to a long (48H) treatment. However, the KEGG signalling pathways namely "tumour necrosis factor (TNF)" and "cytokine-cytokine receptor interaction" were downregulated at 24H but activated at 48H. In addition, at 48H, BPs linked to inflammatory phenotypes were activated (confirming KEGG results), while BPs linked to extracellular matrix (ECM) structural organisation, endothelial cell proliferation, and collagen metabolism were repressed. Lastly, metabolic profiling showed that arachidonic acid, prostaglandins, and palmitic acid were enriched at 48H. This study demonstrates that TMAO induces distinct time-dependent molecular signatures involving inflammation and remodelling pathways, while pathways such as oxidative stress are also modulated, but in a non-time-dependent manner.


Assuntos
Células Endoteliais , Doenças Vasculares , Humanos , Células Endoteliais/metabolismo , Metilaminas/metabolismo , Inflamação/induzido quimicamente , Inflamação/genética , Inflamação/metabolismo , Óxidos
6.
Antioxidants (Basel) ; 12(11)2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-38001785

RESUMO

The mangosteen (Garcinia mangostana L.) pericarp is known to be rich in potent bioactive phytochemical compounds such as xanthones, which possess pharmacologically important antioxidant activity and beneficial cardiometabolic properties. Mangosteen pericarp is typically classified as unavoidable food waste and discarded, despite being rich in bioactive phytochemical compounds that therefore present an exciting opportunity for valorization. Thus, this study aims to extract phytochemical compounds from mangosteen pericarp using pressurized hot water extraction (PHWE) and determine its biological effects in endothelial cells using RNA sequencing. Liquid chromatography with MS/MS (LC/MSMS) and UV detection (LC/UV) was subsequently used to identify three key phytochemical compounds extracted from the mangosteen pericarp: α-Mangostin, γ-Mangostin, and Gartanin. Within the tested range of extraction temperatures by PHWE, our results demonstrated that an extraction temperature of 120 °C yielded the highest concentrations of α-Mangostin, γ-Mangostin, and Gartanin with a concomitant improvement in antioxidant capacity compared to other extraction temperatures. Using global transcriptomic profiling and bioinformatic analysis, the treatment of endothelial cells with mangosteen pericarp extracts (120 °C PHWE) for 48 h caused 408 genes to be differentially expressed. Furthermore, our results demonstrated that key biological processes related to "steroid biosynthesis and metabolism", likely involving the activation of the AMPK signaling pathway, were upregulated by mangosteen pericarp extract treatment. In conclusion, our study suggests a green extraction method to valorize phytochemical compounds from mangosteen pericarp as a natural product with potential beneficial effects on cardiometabolic health.

7.
Int J Bioprint ; 9(5): 776, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37457944

RESUMO

Orange peels are often discarded as food waste despite being a nutritious source of vitamins and antioxidants. These orange peel wastes (OPW) are produced in millions of tons globally every year; discarding them results in detrimental environmental and economical impacts. This paper discusses the application of 3D printing technology to effectively upcycle the OPW into edible, healthy snacks for consumption. We aimed to develop a method to enable OPW to formulate 3D-printable inks for direct ink writing (DIW). Using DIW 3D printing, we successfully created edible constructs of rheologically modified inks containing OPW. The formulated ink possessed an initial viscosity of 22.5 kPa.s, a yield stress of 377 Pa, and a storage modulus of 44.24 kPa. To validate the method, we conducted a biochemical analysis of the OPW at each stage of the fabrication process. This study suggested that our ink formulation and 3D printing process did not affect the content of bioflavonoids and antioxidants of the OPW. The cell viability test using human dermal microvascular endothelium (HMEC-1) suggested that the OPW did not exhibit cytotoxicity throughout the entire process of the ink manipulation. Overall, this study has highlighted a potential scenario to revalorize food waste into the food value chain using 3D printing toward more sustainable and circular food manufacturing and consumption.

8.
Anal Bioanal Chem ; 403(3): 847-56, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22434276

RESUMO

Berberine, long used as a remedy in China and India for intestinal infections, has been discovered in recent years in western countries and is now being used to treat ailments ranging from urinary tract infections to diabetes and obesity. In order to study the effect of berberine more deeply, a combined metabolomic and metallomic approach was developed in this study using the hypercholesterolaemic rat model, which involved the use of proton nuclear magnetic resonance for the analysis of rat urine to achieve metabolic fingerprinting and inductively coupled plasma mass spectrometry for the analysis of rat blood serum to achieve metallomic fingerprinting. The results obtained indicated that major metabolic processes like Krebs cycle, cholesterol metabolism and osmoregulation in hypercholesterolaemic rats are perturbed upon berberine injection. In addition, the changes of some elements, such as V, Mn, Na and K, revealed in the metallomic study may contribute to the search of new biomarkers for hypercholesterolaemic disease. We concluded that both the metabolomic and metallomic profiles of berberine-treated hypercholesterolaemic rats were different from those of the control group and that the selected metabolites and elements could probably be applied as potential biomarkers for the understanding of the effect of berberine on biochemical process in the animal model. Such a multi-analytical approach will potentially provide an information-rich platform for the elucidation of effects of xenobiotics and drug efficacy studies.


Assuntos
Berberina/farmacologia , Hipercolesterolemia/metabolismo , Metaboloma/efeitos dos fármacos , Metabolômica/métodos , Metais/metabolismo , Animais , Coptis/química , Hipercolesterolemia/sangue , Hipercolesterolemia/tratamento farmacológico , Hipercolesterolemia/urina , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Ratos , Ratos Sprague-Dawley
9.
Mol Cell Proteomics ; 2010 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-20147338

RESUMO

Colorectal cancer (CRC) arises as the consequence of progressive changes from normal epithelial cells through polyp to tumor, and thus is an useful model for studying metabolic shift. In the present study, we studied the metabolomic profiles using high analyte specific gas chromatography/mass spectrometry (GC/MS) and liquid chromatography tandem mass spectrometry (LC/MS/MS) to attain a systems-level view of the shift in metabolism in cells progressing along the path to CRC. Colonic tissues including tumor, polyps and adjacent matched normal mucosa from 26 patients with sporadic CRC from freshly isolated resections were used for this study. The metabolic profiles were obtained using GC/MS and LC/MS/MS. Our data suggest there was a distinct profile change of a wide range of metabolites from mucosa to tumor tissues. Various amino acids and lipids in the polyps and tumors were elevated, suggesting higher energy needs for increased cellular proliferation. In contrast, significant depletion of glucose and inositol in polyps revealed that glycolysis may be critical in early tumorigenesis. In addition, the accumulation of hypoxanthine and xanthine, and the decrease of uric acid concentration, suggest that the purine biosynthesis pathway could have been substituted by the salvage pathway in CRC. Further, there was a step-wise reduction of deoxycholic acid concentration from mucosa to tumors. It appears that to gain a growth advantage, cancer cells may adopt alternate metabolic pathways in tumorigenesis and this flexibility allows them to adapt and thrive in harsh environment.

10.
Sci Rep ; 12(1): 13036, 2022 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-35906278

RESUMO

The pulp of avocado (Persea Americana) is widely consumed as the primary food source, while the seed is often discarded as food waste. Increased consumption of avocado would inevitably results in production of waste by-products such as avocado seeds, hence the ability to extract phytochemicals from such waste, and upcycling to potential nutraceutical products is of great interest. The overall aim of this study is to explore avocado seeds as potential functional food through the combined use of a green extraction method, chemical standardization and pattern recognition tools, and biological characterization assays. Specifically, this study utilized an organic solvent-free extraction method, pressurized hot water extraction (PHWE) to extract phytochemicals from avocado seeds and liquid chromatography mass spectrometry (LCMS) was used to identify the phytochemicals present in the avocado seeds. Our results demonstrated that avocado seed extracts have antioxidant activity and inhibited oxidative stress-induced metabolomics changes in endothelial cells, suggesting that avocado seed extracts have vasoprotective actions.


Assuntos
Persea , Eliminação de Resíduos , Antioxidantes/química , Células Endoteliais , Persea/química , Compostos Fitoquímicos/análise , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/química , Sementes/química , Água/análise
11.
Antioxidants (Basel) ; 11(9)2022 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-36139842

RESUMO

Orange peel waste (OPW) is known to contain an abundant amount of polyphenols compounds such as flavonoids, well-reported for their antioxidant and anti-inflammatory properties. While OPW is generally regarded as a food waste, the opportunity to extract bioactive compounds from these "wastes" arises due to their abundance, allowing the investigation of their potential effects on endothelial cells. Hence, this study aims to use a green extraction method and pressurized hot water extraction (PHWE) to extract bioactive compounds from OPW. Liquid chromatography with UV detection (LC/UV) and liquid chromatography mass spectrometry (LC/MS) were subsequently used to identify the bioactive compounds present. Through the optimization of the extraction temperature for PHWE, our results demonstrated that extraction temperatures of 60 °C and 80 °C yield distinct bioactive compounds and resulted in better antioxidant capacity compared to other extraction temperatures or organic solvent extraction. Despite having similar antioxidant capacity, their effects on endothelial cells were distinct. Specifically, treatment of endothelial cells with 60 °C OPW extracts inhibited TNFα-induced vascular inflammation and endothelial dysfunction in vitro, suggesting that OPW possess vasoprotective effects likely mediated by anti-inflammatory effects.

12.
Plants (Basel) ; 10(8)2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-34451690

RESUMO

Abelmoschus esculentus L. Moench (okra) is a commonly consumed vegetable that consists of the seeds and peel component which are rich in polyphenolic compounds. The aim of this study is to utilize pressurized hot water extraction (PHWE) for the extraction of bioactive phytochemicals from different parts of okra. A single step PHWE was performed at various temperatures (60 °C, 80 °C, 100 °C and 120 °C) to determine which extraction temperature exhibits the optimum phytochemical profile, antioxidant and antidiabetic activities. The optimum temperature for PHWE extraction was determined at 80 °C and the biological activities of the different parts of okra (Inner Skin, Outer Skin and Seeds) were characterized using antioxidant (DPPH and ABTS), α-glucosidase and vasoprotective assays. Using PHWE, the different parts of okra displayed distinct phytochemical profiles, which consist of primarily polyphenolic compounds. The okra Seeds were shown to have the most antioxidant capacity and antidiabetic effects compared to other okra parts, likely to be attributed to their higher levels of polyphenolic compounds. Similarly, okra Seeds also reduced vascular inflammation by downregulating TNFα-stimulated VCAM-1 and SELE expression. Furthermore, metabolite profiling by LC/MS also provided evidence of the cytoprotective effect of okra Seeds in endothelial cells. Therefore, the use of PHWE may be an alternative approach for the environmentally friendly extraction and evaluation of plant extracts for functional food applications.

13.
Antioxidants (Basel) ; 9(11)2020 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-33187302

RESUMO

Quinoa is widely noted for its nutritional value. The seed is the main edible part of the plant and exists in at least three different colors: white, red and black. This study utilized a pressurized hot water extraction (PHWE) for the extraction of phytochemicals from quinoa. Chemical fingerprints with LC/UV and LC/MS using a targeted approach and pattern recognition tools were used to evaluate the quinoa extracts. The antioxidant properties for various types of quinoa were evaluated using DPPH assay, ABTS assay and the cytoprotective effect of quinoa extracts were investigated in HMEC-1 cell line. Distinctive chemical profiles obtained from black and red quinoa were well correlated with the antioxidant activities and cytoprotective effects. The combination of PHWE, chemical standardization with LC/UV and LC/MS, pattern recognition tools and biological assay provided an approach for the evaluation and eventual production of quinoa extracts for functional food.

14.
J Sep Sci ; 32(4): 613-22, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19160370

RESUMO

An approach that combined green-solvent methods of extraction with chromatographic chemical fingerprint and pattern recognition tools such as principal component analysis (PCA) was used to evaluate the quality of medicinal plants. Pressurized hot water extraction (PHWE) and microwave-assisted extraction (MAE) were used and their extraction efficiencies to extract two bioactive compounds, namely stevioside (SV) and rebaudioside A (RA), from Stevia rebaudiana Bertoni (SB) under different cultivation conditions were compared. The proposed methods showed that SV and RA could be extracted from SB using pure water under optimized conditions. The extraction efficiency of the methods was observed to be higher or comparable to heating under reflux with water. The method precision (RSD, n = 6) was found to vary from 1.91 to 2.86% for the two different methods on different days. Compared to PHWE, MAE has higher extraction efficiency with shorter extraction time. MAE was also found to extract more chemical constituents and provide distinctive chemical fingerprints for quality control purposes. Thus, a combination of MAE with chromatographic chemical fingerprints and PCA provided a simple and rapid approach for the comparison and classification of medicinal plants from different growth conditions. Hence, the current work highlighted the importance of extraction method in chemical fingerprinting for the classification of medicinal plants from different cultivation conditions with the aid of pattern recognition tools used.


Assuntos
Solventes/química , Stevia/química , Cor , Estrutura Molecular , Pressão , Temperatura , Água
15.
J Chromatogr A ; 1182(1): 34-40, 2008 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-18206897

RESUMO

Our earlier work showed that the stability of the bioactive compounds gastrodin (GA) and vanillyl alcohol (VA) in Gastrodia elata Blume behaved differently with varying compositions of water-ethanol using pressurized liquid extraction (PLE) at room temperature. To have a better understanding of the extraction process of these thermally labile compounds under elevated temperature conditions, pressurized hot water extraction (PHWE) and microwave-assisted extraction (MAE) methods were proposed. PHWE and MAE showed that GA and VA could be extracted using pure water under optimized conditions of temperature and extraction time. The extraction efficiency of GA and VA by the proposed methods was found to be higher or comparable to heating under reflux using water. The marker compounds present in the plant extracts were determined by RP-HPLC. The optimized conditions were found to be different for the two proposed methods on extraction of GA and VA. The method precision (RSD, n=6) was found to vary from 0.92% to 3.36% for the two proposed methods on different days. Hence, PHWE and MAE methods were shown to be feasible alternatives for the extraction of thermally labile marker compounds present in medicinal plants.


Assuntos
Álcoois Benzílicos/química , Gastrodia/química , Glucosídeos/química , Micro-Ondas , Água/química , Fracionamento Químico/métodos , Cromatografia Líquida de Alta Pressão , Extratos Vegetais/química , Plantas Medicinais/química , Reprodutibilidade dos Testes , Temperatura
16.
Mol Neurobiol ; 55(2): 1537-1550, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28181190

RESUMO

Docosahexaenoic acid (DHA) is enriched in membrane phospholipids of the central nervous system (CNS) and has a role in aging and neuropsychiatric disorders. DHA is metabolized by the enzyme Alox15 to 17S-hydroxy-DHA, which is then converted to 7S-hydroperoxy,17S-hydroxy-DHA by a 5-lipoxygenase, and thence via epoxy intermediates to the anti-inflammatory molecule, resolvin D1 (RvD1 or 7S,8R,17S-trihydroxy-docosa-Z,9E,11E,13Z,15E,19Z-hexaenoic acid). In this study, we investigated the distribution and function of Alox15 in the CNS. RT-PCR of the CNS showed that the prefrontal cortex exhibits the highest Alox15 mRNA expression level, followed by the parietal association cortex and secondary auditory cortex, olfactory bulb, motor and somatosensory cortices, and the hippocampus. Western blot analysis was consistent with RT-PCR data, in that the prefrontal cortex, cerebral cortex, hippocampus, and olfactory bulb had high Alox15 protein expression. Immunohistochemistry showed moderate staining in the olfactory bulb, cerebral cortex, septum, striatum, cerebellar cortex, cochlear nuclei, spinal trigeminal nucleus, and dorsal horn of the spinal cord. Immuno-electron microscopy showed localization of Alox15 in dendrites, in the prefrontal cortex. Liquid chromatography mass spectrometry analysis showed significant decrease in resolvin D1 levels in the prefrontal cortex after inhibition or antisense knockdown of Alox15. Alox15 inhibition or antisense knockdown in the prefrontal cortex also blocked long-term potentiation of the hippocampo-prefrontal cortex pathway and increased errors in alternation, in the T-maze test. They indicate that Alox15 processing of DHA contributes to production of resolvin D1 and LTP at hippocampo-prefrontal cortical synapses and associated spatial working memory performance. Together, results provide evidence for a key role of anti-inflammatory molecules generated by Alox15 and DHA, such as resolvin D1, in memory. They suggest that neuroinflammatory brain disorders and chronic neurodegeneration may 'drain' anti-inflammatory molecules that are necessary for normal neuronal signaling, and compromise cognition.


Assuntos
Araquidonato 15-Lipoxigenase/metabolismo , Ácidos Docosa-Hexaenoicos/metabolismo , Memória de Curto Prazo/fisiologia , Córtex Pré-Frontal/metabolismo , Memória Espacial/fisiologia , Animais , Encéfalo/metabolismo , Masculino , Ratos , Ratos Wistar
17.
J Chromatogr A ; 1159(1-2): 242-9, 2007 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-17543977

RESUMO

A new, simple and rapid capillary electrophoresis-mass spectrometry (CE-MS) method, using a cationic polymer-coated capillary to reverse electroosmotic flow, is proposed and validated for the separation and simultaneous quantification of 11 gibberellins (GAs). Under optimum conditions, a baseline separation of 11 GAs, including GA1, GA3, GA4, GA5, GA6, GA7, GA13, GA19, GA20, GA24 and GA53 was accomplished within 25 min using 70 mM ammonium formate/formic acid buffer (pH 3.8) and 2% (v/v) acetonitrile with -25 kV as the separation voltage. Satisfactory results were obtained in terms of linearity (R2 between 0.984 and 0.995), precision (RSD of migration time below 0.8%) and sensitivity (LOD between 0.31 and 1.02 microM). Furthermore, a novel solid-phase extraction (SPE) procedure was developed for the pre-concentration and purification of GAs using Oasis MAX cartridges. The combination of SPE and CE-MS approach was applied to screen for endogenous GAs present in coconut (Cocos nucifera L.) water sample. To illustrate the applicability of the method, GA1 and GA3 were successfully detected and quantified in coconut water. Finally, the GA1 and GA3 identities were further unequivocally confirmed by CE-tandem MS experiments operating in the multiple reaction monitoring mode.


Assuntos
Cocos/química , Eletroforese Capilar/métodos , Giberelinas/análise , Espectrometria de Massas em Tandem/métodos , Soluções Tampão , Materiais Revestidos Biocompatíveis , Eletro-Osmose , Estudos de Viabilidade , Concentração de Íons de Hidrogênio , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Extração em Fase Sólida
18.
Food Chem ; 221: 1388-1393, 2017 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-27979104

RESUMO

In this study, extraction of immature fruits using an environmentally friendly pressurized hot water extraction (PHWE) method was compared with the traditional reflux method. Extracts were tested for their polyphenol content using the Folin-Ciocalteu assay and for their antioxidant activity using the oxygen radical absorbance capacity (ORAC) assay. The highest amount of polyphenol was extracted from grape (stem) using PHWE at 100°C, or reflux extraction. This was followed by reflux extraction of grape (fruit). The results were similar for the ORAC assay. All samples extracted using PHWE at 100°C showed cytoprotective activity against H2O2-induced oxidative stress in Crandell-Reese feline kidney (CRFK) cells. This study demonstrated that beneficial compounds can be extracted from immature fruits without the use of organic solvents. The utilization of beneficial compounds present in immature fruits can also contribute to the reduction in agriculture waste generated.


Assuntos
Antioxidantes/análise , Frutas/química , Extratos Vegetais/química , Polifenóis/análise
19.
Mol Biosyst ; 2(5): 250-8, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16880943

RESUMO

The investigation of differentially expressed proteins was used together with other techniques to study the inhibitory effects of two different doses of berberine in human liver cancer cell line HepG2. For HepG2 cells treated with 24.0 mg l(-1) of berberine, an increase in the sub G(0) phase that was indicative of cell death was observed in cell cycle analysis with flow cytometry. However, no significant increase in sub G(0) was observed in HepG2 cells treated with 4.0 mg l(-1) of berberine. Using flow cytometric analysis, significant activation of caspase 3 was not observed with HepG2 cells treated with 4.0 and 24.0 mg l(-1) of berberine. In this work, labeling of cells with stable isotope was not used in the proposed method developed. The whole cell lysates from the control and treated cells were digested with trypsin and the peptides were separated by two-dimensional (cation exchange and reversed phase) liquid chromatography and tandem mass spectrometry. Our preliminary data showed that the proposed platform provided a rapid approach to study the molecular mechanism due to the inhibitory effects of different doses of the berberine on HepG2 cell lines. This included a network of proteins involved in mitogen-activated protein kinase (MAPK) phosphorelay systems, metabolism, regulation of cell cycle and DNA damage response. The differentially expressed proteins identified using the current approach were consistent with the data obtained from cell cycle analysis with flow cytometry.


Assuntos
Berberina/farmacologia , Proteoma/efeitos dos fármacos , Berberina/uso terapêutico , Ciclo Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão/métodos , Humanos , Concentração Inibidora 50 , Neoplasias Hepáticas/tratamento farmacológico , Espectrometria de Massas/métodos , Proteômica/métodos , Células Tumorais Cultivadas
20.
J Chromatogr A ; 1112(1-2): 92-102, 2006 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-16388815

RESUMO

To reduce the use of organic solvent, pressurized hot water extraction (PHWE) has been shown to be a feasible option for the extraction of bioactive and marker compounds in botanicals and medicinal plants. The parameters that may affect the extraction efficiencies in PHWE include temperature, extraction time and addition of small percentage of organic solvent or surfactants. Currently, applications of PHWE for the extraction of thermally labile compounds in botanicals are still rather limited. PHWE with and without the additional of a small percentage of organic solvent such as ethanol is highly suited for the chemical standardization and quality control of medicinal plants. At the same time, it can be applied at the pilot scale as a manufacturing process for medicinal plants. Surfactant assisted PHWE was found to enhance the extraction of thermally labile and more hydrophobic species in medicinal plants at a lower temperature. The addition of small amount of surfactants in PHWE is highly suited for the determination of bioactive or marker compounds in medicinal plants. With proper optimization, PHWE was observed to have good extraction efficiency and precision when compared to other reference methods of extraction.


Assuntos
Biomarcadores/análise , Fracionamento Químico/métodos , Plantas/química , Fracionamento Químico/instrumentação , Temperatura Alta , Plantas Medicinais/química , Tensoativos , Água
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA