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1.
J Vet Sci ; 25(2): e19, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38568821

RESUMO

A 2-year-old spayed female British Shorthair cat presented with an increased frequency and duration of cough since infant period. Based on radiographic, ultrasonographic, and computed tomography findings, peritoneopericardial diaphragmatic hernia was considered so that repair surgery was planned. During celiotomy, lax diaphragm was identified instead of defect. Transabdominal diaphragmatic plication was performed to resolve lax diaphragm and to prevent recurrence by overlapping relatively normal part of diaphragm. Diagnosed with diaphragmatic eventration postoperatively, the cat showed improvement in clinical signs and imaging results. Transabdominal diaphragmatic plication is a suitable treatment; the patient maintained normally during a 14-month follow-up period.


Assuntos
Doenças do Gato , Eventração Diafragmática , Hérnia Diafragmática , Feminino , Gatos , Animais , Eventração Diafragmática/cirurgia , Eventração Diafragmática/veterinária , Diafragma/cirurgia , Hérnia Diafragmática/veterinária , Doenças do Gato/diagnóstico por imagem , Doenças do Gato/cirurgia
2.
Sci Rep ; 13(1): 15038, 2023 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-37700092

RESUMO

The bioactive compounds and antioxidant activities of propolis extracts were investigated using subcritical water extraction (SWE). SWE was performed by varying temperature (110-200 °C) and time (10-30 min). SWE using only water as solvent successfully to extracted bioactive compounds from propolis using high-purity glass thimbles. The concentrations of galangin (16.37 ± 0.61 mg/g), and chrysin (7.66 ± 0.64 mg/g) were maximal at 200 °C for 20 min, and 170 °C for 20 min, respectively. The antioxidative properties from propolis increased with the increasing extraction temperature and extraction time on SWE. The maximum yields of the total phenolics (226.37 ± 4.37 mg/g), flavonoids (70.28 ± 1.33 mg/g), and antioxidant activities (88.73 ± 0.58%, 98.86 ± 0.69%, and 858.89 ± 11.48 mg/g) were obtained at 200 °C for 20 min. Compared with using ethanol extraction (at 25 °C for 24 h, total phenolics = 176.28 ± 0.35, flavonoids = 56.41 ± 0.65, antioxidant activities = 72.74 ± 0.41%, 95.18 ± 0.11%, 619.51 ± 8.17 mg/g), all yields of SWE extracts obtained at 200 °C for 20 min were higher. SWE is suitable for a much faster and more efficient method extracting bioactive compounds from propolis compared to traditional extraction method.


Assuntos
Ascomicetos , Própole , Abelhas , Animais , Água , Antioxidantes , Flavonoides , Fenóis , Extratos Vegetais
3.
Pharmacol Res Perspect ; 11(4): e01114, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37417539

RESUMO

A growing number of patients with metabolic disorders are receiving statin and antidiabetic therapies as comedications. A signal of increased risk of myotoxicity due to potential interactions between antidiabetics and statins has been detected in previous studies. To investigate the effects of metformin on myopathy risks when added to preexisting statin therapy in dyslipidemia patients, we performed a retrospective cohort study using the Korean national health insurance data in statin-treated dyslipidemia patients with or without concomitant metformin use. We compared the risk of myopathy in statin + metformin users against statin-only users. Hazard ratios (HRs) and 95% confidence intervals (CIs) have been calculated following propensity score (PS) matching between study groups and subsequent stratification per patient factors. We included 4092 and 8161 patients in PS-matched statin + metformin and statin-only groups, respectively. The risk of myopathy decreased when metformin was used together with statins (adjusted HR 0.84; 95% CI 0.71-0.99). In subgroup analyses per individual statin agent and in stratified risk analyses, no specific statin agents or patient factors were associated with statistically significant myopathy risk. This study found that a comedication with metformin was associated with decreased myopathy risk in statin-treated dyslipidemia patients compared to statin-only users. Our findings suggest that metformin may provide protective effects on potential muscle toxicities induced by statin therapy.


Assuntos
Dislipidemias , Inibidores de Hidroximetilglutaril-CoA Redutases , Metformina , Doenças Musculares , Humanos , Metformina/efeitos adversos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Estudos Retrospectivos , Estudos de Coortes , Hipoglicemiantes/uso terapêutico , Doenças Musculares/induzido quimicamente , Doenças Musculares/epidemiologia , Dislipidemias/induzido quimicamente , Dislipidemias/tratamento farmacológico , Dislipidemias/epidemiologia
4.
Food Chem ; 424: 136430, 2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37245473

RESUMO

The conversion of isoflavones during subcritical water extraction were studied using first-order reaction kinetics modeling. Isoflavones were extracted from soybean using temperatures from 100℃ to 180℃ for 3 to 30 min. It was found that malonylgenistin was the most thermally unstable, with little being detected above 100℃. The optimal extraction temperatures for acetylgenistin (AG), genistin (G), and genistein (GE) were 120℃, 150℃, and 180℃, respectively. A larger sum of the numbers of both hydroxyl groups and oxygen molecules was associated with a lower melting point and optimal extraction temperature. Kinetics modeling of reaction rate constant k and activation energy Ea showed that all of the reaction rates tended to increase with temperature, with the relationship fitted well by a first-order model in nonlinear regression. For temperatures between 100℃ and 150℃, AG â†’ G and AG â†’ GE conversions showed the highest rate constants, but G â†’ GE and G â†’ D3 (degraded G) conversions became dominant at 180℃. Chemical compounds studied in this article: genistein (PubChem CID: 5280961), genistin (PubChem CID: 5281377), 6″-O-malonylgenistin (PubChem CID: 15934091), 6″-O-acetylgenistin (PubChem CID: 5315831).


Assuntos
Genisteína , Isoflavonas , Água , Cinética , Solubilidade , Isoflavonas/química , Glycine max/química , Cetonas
5.
Medicine (Baltimore) ; 102(5): e32773, 2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36749259

RESUMO

The purpose of this study was to investigate the clinical effect and safety of thread embedding acupuncture (TEA) in patients with facial nerve palsy sequelae. This was a retrospective observational study on 82 patients treated with TEA from January 2021 to May 2022. The Facial Disability Index (FDI) reported by patients and Sunnybrook Facial Grading System scores assessed by clinical practitioners were used to evaluate the intensity of facial movements, functional problems, and psychosocial status. One-way repeated measure analysis of variance showed that the Sunnybrook Facial Grading System scores improved significantly following the 2nd to 6th TEA treatments (Txs). FDI scores also showed significant increases except for the 4th Tx. Additionally, the physical scores improved significantly among the subscales of FDI, but the social/well-being scores did not. There were no reported serious adverse events or adverse events requiring medical Tx. TEA is a safe Tx that has a clinically cumulative effect, in terms of patient-oriented self-assessment of functional problems and objective facial movements, for treating facial nerve palsy sequelae.


Assuntos
Terapia por Acupuntura , Paralisia de Bell , Paralisia Facial , Humanos , Nervo Facial , Paralisia de Bell/terapia , Estudos Retrospectivos
6.
Front Vet Sci ; 9: 819627, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35782562

RESUMO

Arterial thromboembolism is associated with high morbidity and mortality rates in cats. Definitive diagnosis requires advanced imaging modalities, such as computed tomography angiography (CTA) and contrast-enhanced (CE) magnetic resonance angiography (MRA). However, CTA involves exposure to a large amount of ionized radiation, and CE-MRA can cause systemic nephrogenic fibrosis. Non-contrast-enhanced (NE) MRA can help accurately diagnose vascular lesions without such limitations. In this study, we evaluated the ability of NE-MRA using three-dimensional electrocardiograph-gated fast spin-echo (3D ECG-FSE) and 3D time-of-flight (3D TOF) imaging to visualize the aorta and external iliac arteries in clinically healthy cats and compared the results with those obtained using CE-MRA. All 11 cats underwent 3D ECG-FSE, 3D TOF, and CE-MRA sequences. Relative signal intensity (rSI) for quantitative image analysis and image quality scores (IQS) for qualitative image analysis were assessed; the rSI values based on the 3D TOF evaluations were significantly lower than those obtained using 3D ECG-FSE (aorta 3D TOF: 0.57 ± 0.06, aorta 3D ECG-FSE: 0.83 ± 0.06, P < 0.001; external iliac arteries 3D TOF: 0.45 ± 0.06, external iliac arteries 3D ECG-FSE:0.80 ± 0.05, P < 0.001) and similar to those obtained using CE-MRA (aorta: 0.58 ± 0.05, external iliac arteries: 0.57 ± 0.03). Moreover, IQS obtained using 3D TOF were significantly higher than those obtained using 3D ECG-FSE (aorta 3D TOF: 3.95 ± 0.15, aorta 3D ECG-FSE: 2.32 ± 0.60, P < 0.001; external iliac arteries 3D ECG-FSE: 3.98 ± 0.08, external iliac arteries 3D ECG-FSE: 2.23 ± 0.56, P < 0.001) and similar to those obtained using CE-MRA (aorta: 3.61 ± 0.41, external iliac arteries: 3.57 ± 0.41). Thus, 3D TOF is more suitable and produces consistent image quality for visualizing the aorta and external iliac arteries in clinically healthy cats and this will be of great help in the diagnosis of FATE.

7.
Sensors (Basel) ; 22(11)2022 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-35684654

RESUMO

The core body temperature tends to decrease under general anesthesia. Consequently, monitoring the core body temperature during procedures involving general anesthesia is essential to ensure patient safety. In veterinary medicine, rectal temperature is used as an indicator of the core body temperature, owing to the accuracy and convenience of this approach. Some previous studies involving craniotomy reported differences between the brain and core temperatures under general anesthesia. However, noninvasive imaging techniques are required to ascertain this because invasive brain temperature measurements can cause unintended temperature changes by inserting the temperature sensors into the brain or by performing the surgical operations. In this study, we employed in vivo magnetic resonance thermometry to observe the brain temperatures of patients under general anesthesia using the proton resonance frequency shift method. The rectal temperature was also recorded using a fiber optic thermometer during the MR thermometry to compare with the brain temperature changes. When the rectal temperature decreased by 1.4 ± 0.5 °C (mean ± standard deviation), the brain temperature (white matter) decreased by 4.8 ± 0.5 °C. Furthermore, a difference in the temperature reduction of the different types of brain tissue was observed; the reduction in the temperature of white matter exceeded that of gray matter mainly due to the distribution of blood vessels in the gray matter. We also analyzed and interpreted the core temperature changes with the body conditioning scores of subjects to see how the body weight affected the temperature changes.


Assuntos
Temperatura Corporal , Termometria , Anestesia Geral , Animais , Encéfalo/diagnóstico por imagem , Cães , Humanos , Espectroscopia de Ressonância Magnética , Termometria/métodos
8.
Food Chem ; 388: 133029, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35468459

RESUMO

Subcritical water extraction (SWE) of four flavoring compounds from cinnamon was performed at various temperatures and for various extraction times. The extraction temperature (°C) and time (min) corresponding to the maximum content of flavoring compounds were 190 °C and 5 min for cinnamyl alcohol, 200 °C and 20 min for cinnamic acid, 130 °C and 10 min for cinnamaldehyde, and 170 °C and 20 min for coumarin, respectively. Cinnamaldehyde underwent structural conversion to benzaldehyde via hydrolysis at high temperatures, and the rate of conversion rapidly increased above 150 °C. The extraction efficiency using subcritical water was slightly higher or comparable to that using conventional extractants. SWE is a potential and highly selectivity technology for extracting flavoring compounds from cinnamon.


Assuntos
Cinnamomum zeylanicum , Óleos Voláteis , Cinnamomum zeylanicum/química , Aromatizantes , Hidrólise , Água
9.
Foods ; 11(8)2022 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-35454657

RESUMO

Pulsed electric field (PEF) treatment promotes the electroporation of biological membranes, and if included as a pre-treatment, could improve the extraction of certain constituents therefrom. The aim of this study was to determine the optimal extraction conditions for extracting the flavonoid quercetin from dried onion skin and to establish whether the yield could be enhanced by combining PEF pre-treatment with an eco-friendly extraction method that uses subcritical water extraction (SWE). Samples of onion skin were treated with PEF under conditions of varying electric field strength (0.5-2.5 kV/cm) and duration (5-120 s). SWE was then performed with an extraction time of 15 min and at temperatures ranging from 105 °C to 185 °C. Among the conditions tested, the yield of total quercetin was the highest after pretreatment with PEF at 2.5 kV/cm for 15 s, followed by SWE at 145 °C for 15 min (yield 19.25 ± 0.77 mg/g dried onion skin, mean ± standard deviation). Pretreatment with PEF improved the yield of total quercetin extracted by 33.22% compared with the PEF-untreated samples. These findings demonstrate that pretreatment of onion skin with PEF has the potential to improve flavonoid extraction.

10.
Food Chem ; 381: 132192, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35121309

RESUMO

Caraway contains terpenes such as carvone, limonene and carveol, that have antibacterial and antifungal properties. Subcritical-water extraction (SWE) can be used to extract terpenes by changing temperature under high pressure. This study evaluated the SWE of terpenes from caraway when varying the extraction conditions of temperature (110 °C-190 °C), time (5-15 min), and particle size (>1000, 850-1000, 425-850, and < 425 µm). The optimal conditions for the extraction of carvone, which determines the quality of caraway, were found to be 170 °C, 15 min, and a particle size of < 425 µm. Also, the carvone yield was much higher when using SWE (28.5 mg/g caraway) than for solvent extraction (20.2 mg/g caraway) and hydrodistillation (19.8 mg/g caraway). The overall results showed that oxygenated terpene like carvone has a high solubility in subcritical water, and nonoxygenated terpene like limonene can partially be converted to carvone via a process of SWE.


Assuntos
Carum , Limoneno , Solubilidade , Terpenos , Água
11.
Food Sci Biotechnol ; 30(12): 1527-1533, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34642565

RESUMO

Subcritical water extraction is an efficient technique for extracting components from various plants by changing the polarity of water. ß-caryophyllene is a natural bicyclic sesquiterpene with the highest content found among black pepper essential oils. In this study, the efficiency of extraction and yield of ß-caryophyllene from black pepper were investigated using a subcritical water extraction technique. The optimal conditions of ß-caryophyllene (1.19 ± 0.38 mg/g), and caryophyllene oxide (0.82 ± 0.38 mg/g) were obtained from black pepper under extraction conditions of 170 °C/10 min, and 200 °C/15 min, respectively. As the extraction temperature was increased, ß-caryophyllene oxidation proceeded and the extraction content of caryophyllene oxide increased. It is anticipated that both ß-caryophyllene and caryophyllene oxide with high biological activity can be used to selectively extract compounds using subcritical water extraction, which will be helpful in industrial applications.

12.
Foods ; 10(3)2021 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-33802508

RESUMO

This study determines the optimal extraction conditions for the subcritical-water extraction (SWE) of anthocyanin from blueberries and chokeberries and compares the performance using conventional extraction methods. SWE is carried out under different conditions of extraction temperature (110 °C, 130 °C, 150 °C, 170 °C, 190 °C, and 200 °C), extraction time (1, 3, 5, and 10 min), and solvent pH (water and 1% citric acid). The solubility and stability of anthocyanin from blueberries and chokeberries influences the optimal condition for SWE. The presence of more methoxy and hydroxyl functional groups in the basic skeleton of anthocyanin will result in a lower solubility at a high temperature. Water at a higher temperature exhibits a better dissociation reaction, and a solvent has a lower pH at a higher temperature. One percent citric acid is used to reduce the pH of the solvent, which increases the extraction efficiency of anthocyanin in a subcritical water state.

13.
Food Sci Biotechnol ; 30(2): 217-226, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33732512

RESUMO

The objective of this study was to identify whether the efficacy of extracting hesperidin and narirutin from Citrus unshiu peel by-products can be increased by combining pulsed electric field (PEF) and subcritical water extraction (SWE). The samples were treated with a PEF at a strength of 3 kV/cm for 60 and 120 s. Subsequent SWE was conducted at extraction temperatures of 110-190 °C for 3-15 min. The concentration of hesperidin was highest at 46.96 ± 3.37 mg/g peel (dry basis) after PEF treatment at 120 s, combined with SWE at 150 °C for 15 min, while that of narirutin peaked at 8.76 ± 0.83 mg/g after PEF treatment at 120 s, integrated with SWE at 190 °C for 5 min. The concentrations of both hesperidin and narirutin increased with PEF treatment time. The PEF increased the amounts of hesperidin and narirutin extracted by 22.1% and 33.6%, respectively. This study demonstrate the potential of PEF pretreatment for enhancing the SWE of flavonoids from C. unshiu peel.

14.
Sci Rep ; 10(1): 10890, 2020 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-32616865

RESUMO

Subcritical-water extraction is an ecofriendly method for extracting antioxidant compounds only using water. The Subcritical-water extraction was employed for the extraction of bioactive compounds from Orostachys japonicus known as rock pine by investigating the use of various temperatures (110-260 °C) and extraction times (5-20 min). The Subcritical-water extraction condition at 220 °C for 15 min; the total phenolics content (39.9 ± 4.1 mg/g), flavonoids content (11.4 ± 0.6 mg/g), and antioxidant activities (90.3 ± 2.2%, 96.0 ± 2.9%, and 662.4 ± 17.2 mg/g) of Subcritical-water extract were higher under this condition than for extraction with either methanol or ethanol. Triterpene saponins were observed only in subcritical-water extraction condition at 220 °C for 15 min. Further, some of its phenolic constituents; gallic acid, quercetin, and kaempferol were quantified by high performance liquid chromatography. Subcritical-water extraction is an effective method for extracting valuable bioactive compounds from Orostachys japonicus.


Assuntos
Antioxidantes/isolamento & purificação , Crassulaceae/química , Flavonoides/isolamento & purificação , Fenóis/isolamento & purificação , Plantas Medicinais/química , Benzotiazóis , Compostos de Bifenilo , Cromatografia Líquida de Alta Pressão , Etanol , Sequestradores de Radicais Livres/isolamento & purificação , Ácido Gálico/isolamento & purificação , Metanol , Picratos , Extratos Vegetais/química , Saponinas/isolamento & purificação , Solventes , Ácidos Sulfônicos , Triterpenos/isolamento & purificação , Água
15.
Food Sci Biotechnol ; 29(5): 631-639, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32419961

RESUMO

Active components were extracted from Angelica gigas Nakai by subcritical-water extraction (SWE) with the purpose of determining how the extraction conditions affect the SWE of antioxidant properties and active components (nodakenin and decursin), and to compare pilot-scale SWE (8 L) and conventional extraction methods. The extraction yields of nodakenin and decursin in the pilot-scale system were highest at 150 °C for 10 min and 190 °C for 15 min, respectively. The extraction yield of decursin increased as the stirring speed was increased to 200-250 rpm. Pearson's correlation indicated that the radical-scavenging activities using DPPH and ABTS assays were more sensitive to the Maillard reaction (R2 = 0.822 and 0.933, respectively) than to the total phenolic contents (R2 = 0.486 and 0.724, respectively). The extraction yield of decursin was higher when using conventional extraction methods than for SWE.

16.
Food Chem ; 308: 125670, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31655478

RESUMO

Oat (Avena sativa L.) ß-glucan is bound tightly to other components of the endosperm cell wall, which means that ß-glucan extraction processes are complex and involve many different stages. Subcritical-water extraction (SWE) has emerged as a promising method for extracting ß-glucan under high temperature and pressure conditions. This study investigated the efficiency of the SWE of ß-glucan from oat flour. The yield of ß-glucan was optimized under the following conditions: extraction temperature of 200 °C, solvent pH of 4.0, extraction time of 10 min, and particle size of 425-850 µm. The extraction yield under the optimal condition was 6.98 ±â€¯1.17 g/100 g oat flour, which was more than twofold higher than when using hot-water extraction at 60 °C for 3 h. ß-glucan degradation to 5-hydroxymethyl-2-furaldehyde was increased under high-temperature conditions. SWE is a feasible alternative for extracting ß-glucan in a single-step process, and could be developed into an effective industrial process.


Assuntos
Avena/química , Farinha/análise , beta-Glucanas/química , Temperatura Alta , Hidrólise , Solventes , Água
17.
Food Chem ; 270: 149-155, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30174028

RESUMO

Subcritical water extraction is an eco-friendly method for the extraction of less polar compounds without the use of organic solvents. This study determined the extraction conditions that maximize the contents of 6-gingerol and 6-shogaol obtained from ginger pulp and peel. The highest yields of 6-gingerol (0.68 ±â€¯0.08 mg/g), and 6-shogaol (0.39 ±â€¯0.03 mg/g) were obtained from ginger pulp at the extraction conditions of 130 °C/25 min, and 190 °C/15 min. 6-Shogaol content increased with the increasing extraction temperature and extraction time due to the conversion of 6-gingerol to 6-shogaol by thermal cracking. The antioxidant activity of ginger extracts were increased depending on the increasing of 6-shogaol content.


Assuntos
Catecóis/química , Álcoois Graxos/química , Água/química , Zingiber officinale , Extratos Vegetais
18.
Food Chem ; 168: 21-6, 2015 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-25172678

RESUMO

This study compared the efficiencies of using subcritical water, hot water, and organic solvents to extract flavonols from black tea, celery, and ginseng leaf. The effect of key operating conditions was determined by varying the temperature (110-200°C), extraction time (5-15min), and pressure (about 10MPa) and the extracts were analysed quantitatively using HPLC. The yields of myricetin, quercetin, and kaempferol from plants were maximal at extraction temperatures of 170°C, 170°C and 200°C, respectively, and they depend on the number of hydroxyl groups included in the chemical structure of the flavonols, with more of those with fewer hydroxyl (OH) groups attached being extracted at higher temperatures. The results also showed that the yields of flavonols by subcritical water extraction were 2.0- to 22.7- and 1.8- to 23.6-fold higher than those obtained using the ethanol and methanol as traditional extraction methods, respectively.


Assuntos
Apium/química , Camellia sinensis/química , Flavonóis/química , Panax/química , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Fracionamento Químico , Cromatografia Líquida de Alta Pressão/métodos , Flavonóis/análise , Estrutura Molecular , Quercetina/análise , Água/química
19.
J Agric Food Chem ; 62(28): 6828-33, 2014 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-24918863

RESUMO

The subcritical-water extraction (SWE) of six kinds of flavanols from green tea leaves and the effect of extraction conditions were investigated by varying the temperature and time. The maximum yield of total flavanols, 71.36 ± 4.23 mg/g green tea leaves (mean ± SD), was obtained under extraction temperature/time conditions of 150 °C/5 min. The efficiency of SWE for total flavanols was slightly higher than that of the conventional extraction solvents such as methanol and ethanol. The extraction of flavanols via SWE was specifically adequate for epimer structures such as catechin, catechin gallate, and gallocatechin gallate due to the epimerization of epicatechins. The extraction efficiency of epimers was increased at temperatures up to 170 °C, whereas that of epicatechins was decreased. Thus, most epicatechins were converted to epimers during SWE, leading to some flavanol destruction at high temperatures, except when a short extraction time of 5 min was used.


Assuntos
Camellia sinensis/química , Catequina/isolamento & purificação , Flavonoides/isolamento & purificação , Folhas de Planta/química , Extratos de Tecidos/química , Antioxidantes/isolamento & purificação , Cromatografia Líquida de Alta Pressão/métodos , Solubilidade , Solventes , Água
20.
Food Chem ; 143: 147-55, 2014 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-24054224

RESUMO

Subcritical water (about 10MPa) is an excellent solvent for extracting non-polar flavonoids by varying the temperature-dependent dielectric constant. This study determined the optimum conditions for subcritical water extraction (SWE), such as the time and temperature, for extracting flavonoids from eight plants, and their dependence on the chemical structure of flavonoids (polarity of side chains and the presence of sugar, and double bonds). Flavonoids having an OH side chain (quercetin at 170°C/10min) were optimally extracted at lower temperatures than O-CH3 (isorhamnetin at 190°C/15min) and H (kaempferol at 190°C/15min) side chains. The optimal temperatures of the glycoside forms including sugar, such as quercitrin (110°C/5min), spiraeoside (150°C/15min), and isoquercitrin (150°C/15min), were lower than of the less-polar aglycones (170°C/10min and 190°C/15min). Apigenin, having double bonds, was extracted well at a higher temperature (190°C/15min) than naringenin (170°C/15min) in SWE.


Assuntos
Fracionamento Químico/métodos , Flavonoides/química , Flavonoides/isolamento & purificação , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Plantas/química , Água/química , Temperatura Alta , Estrutura Molecular , Solubilidade
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