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1.
Chemosphere ; 309(Pt 1): 136725, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36208804

RESUMO

Simultaneous multiresidual pesticide analysis of saliva samples was performed using scaled-down QuEChERS extraction with LC-MS/MS and GC-MS/MS. The optimum extraction procedure using acidified acetonitrile was applicable to 336 pesticides (287 for LC-MS/MS and 49 for GC-MS/MS). To determine pesticide multiresidues in saliva, 100 µL of the sample was extracted with 200 µL of 0.1% formic acid in acetonitrile, and the initial extract was partitioned with 40 mg of MgSO4 and 10 mg of NaCl. The organic supernatants (120 µL) were then mixed with acetonitrile (30 µL) for matrix-matching (4:1, v/v), and the final extract solution was injected into the LC-MS/MS (4 µL) and GC-MS/MS (2 µL) systems. The established analytical method showed a good LOQs between 5 and 25 ng/mL with reliable accuracy/precision values and recovery results (50-140%) for the target pesticides. Under the two different storage conditions, most of the analytes did not undergo chemical changes in the saliva samples, whereas some pesticides were more stable in freeze-thaw processes than those left at room temperature. Biomonitoring of farmers (ten mixers and ten sprayers) was successfully applied using the validated method, and two carbamates (fenobucarb and propamocarb) were determined at trace concentrations (12.5-675.0 ng/mL from 11 positively detected samples).


Assuntos
Resíduos de Praguicidas , Praguicidas , Humanos , Praguicidas/análise , Cromatografia Líquida , Espectrometria de Massas em Tandem/métodos , Resíduos de Praguicidas/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Monitoramento Biológico , Fazendeiros , Saliva/química , Cloreto de Sódio/análise , Acetonitrilas/análise , Carbamatos/análise , Extratos Vegetais/análise
2.
Molecules ; 26(9)2021 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-34063650

RESUMO

Coffee has been shown to attenuate sarcopenia, the age-associated muscle atrophy. Myostatin (MSTN), a member of the TGF-ß growth/differentiation factor superfamily, is a potent negative regulator of skeletal muscle mass, and MSTN-inhibition increases muscle mass or prevents muscle atrophy. This study, thus, investigated the presence of MSTN-inhibitory capacity in coffee extracts. The ethanol-extract of coffee silverskin (CSE) but not other extracts demonstrated anti-MSTN activity in a pGL3-(CAGA)12-luciferase reporter gene assay. CSE also blocked Smad3 phosphorylation induced by MSTN but not by GDF11 or Activin A in Western blot analysis, demonstrating its capacity to block the binding of MSTN to its receptor. Oral administration of CSE significantly increased forelimb muscle mass and grip strength in mice. Using solvent partitioning, solid-phase chromatography, and reverse-phase HPLC, two peaks having MSTN-inhibitory capacity were purified from CSE. The two peaks were identified as ßN-arachinoyl-5-hydroxytryptamide (C20-5HT) and ßN-behenoyl-5-hydroxytryptamide (C22-5HT) using mass spectrometry and NMR analysis. In summary, the results show that CSE has the MSTN-inhibitory capacity, and C20-5HT and C22-5HT are active components of CSE-suppressing MSTN activity, suggesting the potential of CSE, C20-5HT, and C22-5HT being developed as agents to combat muscle atrophy and metabolic syndrome.


Assuntos
Café/metabolismo , Músculo Esquelético/metabolismo , Músculos/efeitos dos fármacos , Miostatina/antagonistas & inibidores , Administração Oral , Animais , Glicemia/análise , Peso Corporal , Osso e Ossos/metabolismo , Etanol , Ácidos Graxos não Esterificados/metabolismo , Concentração Inibidora 50 , Masculino , Síndrome Metabólica/metabolismo , Camundongos , Camundongos Endogâmicos ICR , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , RNA Mensageiro/metabolismo , Solventes/química , Fator de Crescimento Transformador beta/metabolismo , Proteína Desacopladora 1/metabolismo
3.
Nutr Metab (Lond) ; 17: 44, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32549901

RESUMO

BACKGROUND: Vitamin D deficiency has been often observed in obese persons. One of the mechanisms suggested for low vitamin D status in obesity was decreased bioavailability of vitamin D (VD) due to sequestration in adipose tissue. However, only few studies have investigated this mechanism via quantifying vitamin D levels from tissues from the obese. METHODS: Six-wk-old C57BL/6 mice were fed 10 or 45% kcal fat (CON or HFD) diets containing 50, 1000 or 25,000 IU vitamin D3/kg diet (LVd, CVd or HVd) for 13 wks. Serum 25-hydroxyvitamin D (25(OH)D) levels were determined by radioimmunoassay and liver and adipose tissue cholecalciferol (VD3) and 25-hydrocholecalciferol (25(OH)D3) levels were measured by LC-MS/MS. mRNA levels of jejunal Mttp, Cd36, Sr-b1, Npc1l1, and Abca1 and liver and adipose tissue 25-hydroxylases (Cyp2r1 and Cyp27a1) were determined by real-time PCR. RESULTS: Serum 25(OH)D levels were affected by dietary vitamin D content but differential effects were observed between HFD and CON groups. When vitamin D intake was at a supplementary level, the HFD-HVd group had lower serum 25(OH)D levels than the CON-HVd group, while there was no significant difference between the HFD and CON groups fed LVd or CVd. Total amount of VD3 in liver and adipose tissue were significantly higher in HFD-HVd group compared with the CON-HVd group. However, no difference in total amount of tissue VD3 was observed between the CON and HFD groups fed CVd. In jejunum, mRNA levels of Mttp and Abca1 were significantly higher in HFD groups than CON groups. There was no difference in mRNA levels of liver 25-hydroxylases by both dietary fat amount and vitamin D content. CONCLUSION: A significant amount of VD3 seemed to be stored in the liver and adipose tissue when dietary vitamin D is at a supplementation level; thus excess body adiposity could contribute to relatively low serum 25(OH)D level when vitamin D was supplemented.

4.
J Agric Food Chem ; 65(16): 3387-3395, 2017 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-28345909

RESUMO

A multiresidue method for the simultaneous and rapid analysis of 360 pesticides in representative agricultural produce (brown rice, orange, spinach, and potato) was developed using a modified QuEChERS procedure combined with gas chromatography-tandem mass spectrometry (GC-MS/MS). Selected reaction monitoring transition parameters (e.g., collision energy, precursor and product ions) in MS/MS were optimized to achieve the best selectivity and sensitivity for a wide range of GC-amenable pesticides. A short (20 m) microbore (0.18 mm i.d.) column resulted in better signal-to-noise ratio with reduced analysis time than a conventional narrowbore column (30 m × 0.25 mm i.d.). The priming injection dramatically increased peak areas by masking effect on a new GC liner. The limit of quantitation was <0.01 mg/kg, and the correlation coefficients (r2) of matrix-matched standards were >0.99 within the range of 0.0025-0.1 mg/kg. Acetonitrile with 0.1% formic acid without additional buffer salts was used for pesticide extraction, whereas only primary-secondary amine (PSA) was used for dispersive solid phase extraction (dSPE) cleanup, to achieve good recoveries for most of the target analytes. The recoveries ranged from 70 to 120% with relative standard deviations of ≤20% at 0.01 and 0.05 mg/kg spiking levels (n = 6) in all samples, indicating acceptable accuracy and precision of the method. Seventeen real samples from local markets were analyzed by using the optimized method, and 14 pesticides in 11 incurred samples were found at below the maximum residue limits.


Assuntos
Citrus sinensis/química , Contaminação de Alimentos/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Oryza/química , Resíduos de Praguicidas/química , Solanum tuberosum/química , Spinacia oleracea/química , Limite de Detecção
5.
World J Microbiol Biotechnol ; 28(4): 1575-83, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22805939

RESUMO

The growth-inhibiting activities of Paeonia lactiflora (Paeoniaceae) root steam distillate constituents and structurally related compounds against nine harmful intestinal bacteria and eight lactic acid-producing bacteria were compared with those of two antibiotics, amoxicillin and tetracycline. Thymol, α-terpinolene, (-)-perilla alcohol and (1R)-(-)-myrtenol exhibited high to extremely high levels of growth inhibition of all the harmful bacteria, whereas thymol and α-terpinolene (except for Lactobacillus casei ATCC 393) inhibited the growth of all the beneficial bacteria (MIC, both 0.08-0.62 mg mL(-1)). Tetracycline and amoxicillin exhibited extremely high level of growth inhibition of all the test bacteria (MIC, <0.00002-0.001 mg mL(-1)). 1,8-Cineole, geraniol, (-)-borneol, (1S,2S,5S)-(-)-myrtanol, nerol, (S)-(-)-ß-citronellol and (±)-lavandulol also exhibited inhibitory activity but with differing specificity and levels of activity. Structure-activity relationship indicates that structural characteristics, such as geometric isomerism, degrees of saturation, types of functional groups and types of carbon skeleton, appear to play a role in determining the growth-inhibiting activity of monoterpenoids. Global efforts to reduce the level of antibiotics justify further studies on naturally occurring P. lactiflora root-derived materials as potential preventive agents against various diseases caused by harmful intestinal bacteria such as clostridia.


Assuntos
Antibacterianos/farmacologia , Enterobacteriaceae/efeitos dos fármacos , Paeonia/química , Extratos Vegetais/farmacologia , Raízes de Plantas/química , Amoxicilina/farmacologia , Antibacterianos/química , Antibacterianos/isolamento & purificação , Humanos , Lactobacillales/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Vapor , Relação Estrutura-Atividade , Tetraciclina/farmacologia
6.
Korean J Hepatol ; 15(4): 504-9, 2009 Dec.
Artigo em Coreano | MEDLINE | ID: mdl-20037269

RESUMO

Herbal remedies and health foods are widely used, and their side effects have been reported. We describe two cases of symptomatic toxic hepatitis that developed in middle-aged women after ingesting arrowroot juice. The clinical manifestations were nausea, vomiting, and jaundice. The diagnosis of toxic hepatitis was made using the Roussel Uclaf Causality Assessment Method score on the basis of the patient's history and laboratory data. After supportive care, the patients showed rapid improvements of clinical symptoms, laboratory findings, and liver stiffness. Clinicians should be aware that the consumption of arrowroot juice can cause toxic hepatitis.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/diagnóstico , Marantaceae/química , Extratos Vegetais/toxicidade , Alanina Transaminase/sangue , Aspartato Aminotransferases/sangue , Doença Hepática Induzida por Substâncias e Drogas/complicações , Doença Hepática Induzida por Substâncias e Drogas/diagnóstico por imagem , Técnicas de Imagem por Elasticidade , Exantema/complicações , Feminino , Humanos , Pessoa de Meia-Idade
7.
Drug Metab Dispos ; 36(6): 1010-5, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18332082

RESUMO

Woohwangcheongsimwon is a traditional medicine for treating hypertension, arteriosclerosis, coma, and stroke in China and Korea. To assess potential interactions of herb and drug metabolism, commercially available Woohwangcheongsimwon suspensions were examined for their potential to inhibit the activity of nine human cytochrome P450 enzymes. The Woohwangcheongsimwon suspensions showed strong inhibition of CYP2B6 activity. To identify individual constituents with inhibitory activity, the suspension was partitioned using hexane, ethyl acetate, and dichloromethane, and each fraction was tested for its inhibitory effect on CYP2B6-catalyzed bupropion hydroxylation. The hexane fraction possessed inhibitory activity, and gas chromatography/mass spectrometry analysis identified borneol and isoborneol as major constituents of the hexane fraction. These two terpenoids moderately inhibited CYP2B6-catalyzed bupropion hydroxylase activity in a competitive manner, with K(i) values of 9.5 and 5.9 microM, respectively, as well as efavirenz 8-hydroxylase activity, with K(i) values of 22 and 26 microM, respectively. Additionally, reconstituted mixtures of borneol and isoborneol, at the same concentrations as in the Woohwangcheongsimwon suspension, had comparable potency in inhibiting bupropion hydroxylation. These in vitro data indicate that Woohwangcheongsimwon preparations contain constituents that can potently inhibit the activity of CYP2B6 and suggest that these preparations should be examined for potential pharmacokinetic drug interactions in vivo.


Assuntos
Hidrocarboneto de Aril Hidroxilases/antagonistas & inibidores , Canfanos/farmacologia , Interações Ervas-Drogas , Oxirredutases N-Desmetilantes/antagonistas & inibidores , Preparações de Plantas/farmacologia , China , Citocromo P-450 CYP2B6 , Humanos , Coreia (Geográfico) , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/metabolismo , Oxigenases de Função Mista/metabolismo , Fitoterapia , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/prevenção & controle , Suspensões
8.
Phytomedicine ; 15(6-7): 533-5, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17913482

RESUMO

Antimalarial activity of anthothecol, a limonoid of Khaya anthotheca (Meliaceae) against Plasmodium falciparum was tested using a [(3)H]-hypoxanthine and 48h culture assay in vitro. Anthotechol showed potent antimalarial activity against malaria parasites with IC(50) values of 1.4 and 0.17microM using two different assays. Also, gedunin had antimalarial activity with IC(50) values of 3.1 and 0.14microM. However, the citrus limonoids, limonin and obacunone did not show any antimalarial activity. The antimalarial activities were compared with the three currently used antimalarial medicines quinine, chloroquinine and artemisinin.


Assuntos
Antimaláricos/farmacologia , Limoninas/farmacologia , Meliaceae/química , Plasmodium falciparum/efeitos dos fármacos , Animais , Antimaláricos/química , Antimaláricos/isolamento & purificação , Células Cultivadas , Humanos , Hipoxantina , Limoninas/química , Limoninas/isolamento & purificação , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Estrutura Molecular , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Espectrometria de Massas por Ionização por Electrospray , Trítio
9.
J Ethnopharmacol ; 108(1): 148-51, 2006 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-16766151

RESUMO

The antiplatelet and antiproliferative activities of extract of Tabebuia impetiginosa inner bark (taheebo) were investigated using washed rabbit platelets and cultured rat aortic vascular smooth muscle cells (VSMCs) in vitro. n-Hexane, chloroform and ethyl acetate fractions showed marked and selective inhibition of platelet aggregation induced by collagen and arachidonic acid (AA) in a dose-dependent manner. These fractions, especially the chloroform fraction, also significantly suppressed AA liberation induced by collagen in [(3)H]AA-labeled rabbit platelets. The fractions, especially the chloroform fraction, potently inhibited cell proliferation and DNA synthesis induced by platelet derived growth factor (PDGF)-BB, and inhibited the levels of phosphorylated extracellular signal regulated kinase (ERK1/2) mitogen activated protein kinase (MAPK) stimulated by PDGF-BB, in the same concentration range that inhibits VSMC proliferation and DNA synthesis.


Assuntos
Ácido Araquidônico/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Miócitos de Músculo Liso/efeitos dos fármacos , Casca de Planta/química , Preparações de Plantas/farmacologia , Agregação Plaquetária/efeitos dos fármacos , Tabebuia/química , Animais , Proliferação de Células/efeitos dos fármacos , Músculo Liso Vascular/citologia , Miócitos de Músculo Liso/citologia , Preparações de Plantas/química , Coelhos , Ratos
10.
J Ethnopharmacol ; 105(1-2): 255-62, 2006 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-16359837

RESUMO

The growth-inhibiting activity of Tabebuia impetiginosa Martius ex DC dried inner bark-derived constituents against Helicobacter pylori ATCC 43504 was examined using paper disc diffusion and minimum inhibitory concentration (MIC) bioassays. The activity of the isolated compounds was compared to that of the commercially available anti-Helicobacter pylori agents, amoxicillin, metronidazole, and tetracycline. The biologically active components of Tabebuia impetiginosa dried inner bark (taheebo) were characterized by spectroscopic analysis as 2-(hydroxymethyl)anthraquinone, anthraquinone-2-carboxylic acid, and 2-hydroxy-3-(3-methyl-2-butenyl)-1,4-naphthoquinone (lapachol). With the paper disc diffusion assay 2-(hydroxymethyl)anthraquinone exhibited strong activity against Helicobacter pylori ATCC 43504 at 0.01 mg/disc. Anthraquinone-2-carboxylic acid, lapachol and metronidazole were less effective, exhibiting moderate anti-Helicobacter pylori activity at 0.1 mg/disc. Amoxicillin and tetracycline were the most potent compounds tested, displaying very strong activity at 0.005 mg/disc. 2-(Hydroxymethyl)anthraquinone exhibited moderate activity at this dose. Tetracycline still had strong activity at 0.001 mg/disc while amoxicillin had little activity at this dose. In the MIC bioassay, 2-(hydroxymethyl)anthraquinone (2 microg/mL), anthraquinone-2-carboxylic acid (8 microg/mL), and lapachol (4 microg/mL) were more active than metronidazole (32 microg/mL) but less effective than amoxicillin (0.063 microg/mL) and tetracycline (0.5 microg/mL). The anti-Helicobacter pylori activity of seven 1,4-naphthoquinone derivatives (structurally related to lapachol), 1,4-naphthoquinone, 5,8-dihydroxy-1,4-naphthoquinone (naphthazarin), 2-methyl-1,4-naphthoquinone (menadione), 2-hydroxy-1,4-naphthoquinone (lawsone), 5-hydroxy-2-methyl-1,4-naphthoquinone (plumbagin), 5-hydroxy-1,4-naphthoquinone (juglone), and 2,3-dichloro-1,4-naphthoquinone (dichlone) was also evaluated using the paper disc assay. Menadione and plumbagin were the most potent compounds tested with the later still exhibiting very strong activity at 0.001 mg/disc. Menadione, juglone and tetracycline had strong activity at this low dose while the latter two compounds and amoxicillin had very strong activity at 0.005 mg/disc. Lawsone was unusual in that it had very strong activity at 0.1 and 0.05 mg/disc but weak activity at doses of 0.01 mg/disc and lower. Naphthazalin, lapachol and dichlone had similar activities while metronidazole had the lowest activity of all compounds tested. These results may be an indication of at least one of the pharmacological actions of taheebo. The Tabebuia impetiginosa dried inner bark-derived materials, particularly 2-(hydroxymethyl)anthraquinone, merit further study as potential Helicobacter pylori eradicating agents or lead compounds.


Assuntos
Antibacterianos/farmacologia , Helicobacter pylori/efeitos dos fármacos , Extratos Vegetais/farmacologia , Tabebuia/química , Espectroscopia de Ressonância Magnética , Espectrometria de Massas/métodos , Testes de Sensibilidade Microbiana , Espectroscopia de Infravermelho com Transformada de Fourier
11.
J Ethnopharmacol ; 100(1-2): 176-9, 2005 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-15941638

RESUMO

The effects of methanol extract from Hericium erinaceus cultivated with Artemisia iwayomogi (HEAI) on proliferation of vascular smooth muscle cells and CCl(4)-induced hepatic damage were evaluated. HEAI was shown to have a potent inhibitory effect on the proliferation of vascular smooth muscle cells (VSMCs). Interestingly, a methanol extract of Hericium erinaceus showed no inhibitory effect on the proliferation of VSMCs, while a methanol extract of Artemisia iwayomogi possessed strong inhibitory effects on the proliferation of VSMCs. Therefore, the inhibitory effects of HEAI may be caused by the changes of chemical components in the culture broth after the addition of Artemisia iwayomogi in the HEAI growth media. HEAI also had a strong protective effect on CCl(4)-induced hepatic damage in rats. The activity was evaluated using biochemical parameters such as glutamic oxalacetic transaminase (GOT), glutamic pyruvic transaminase (GPT) and alkaline phosphatase (ALP). HEAI treatment caused a significant reduction in the activity of GOT but not of GPT and ALP in comparison with CCl(4) treatment alone. Histopathological studies showed that liver samples treated with HEAI were significantly different when compared to non-treated animals after CCl(4) exposure.


Assuntos
Basidiomycota/química , Proliferação de Células/efeitos dos fármacos , Hepatopatias/tratamento farmacológico , Músculo Liso Vascular/efeitos dos fármacos , Extratos Vegetais/farmacologia , Animais , Tetracloreto de Carbono/antagonistas & inibidores , Doença Hepática Induzida por Substâncias e Drogas , Relação Dose-Resposta a Droga , Masculino , Músculo Liso Vascular/fisiologia , Extratos Vegetais/química , Ratos
12.
J Am Mosq Control Assoc ; 21(1): 80-3, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15825766

RESUMO

Five monoterpenes (carvacrol, p-cymene, linalool, alpha-terpinene, and thymol) derived from the essential oil of thyme (Thymus vulgaris) were examined for their repellency against the mosquito Culex pipiens pallens. All 5 monoterpenes effectively repelled mosquitoes based on a human forearm bioassay. Alpha-terpinene and carvacrol showed significantly greater repellency than a commercial formulation, N,N-diethyl-m-methylbenzamide (deet), whereas thymol showed similar repellency to that of deet. The duration of repellency after application for all these monoterpenes was equal to or higher than that of deet. These findings indicate that a spray-type solution containing 2% alpha-terpinene may serve as an alternative mosquito repellent.


Assuntos
Culex , Repelentes de Insetos , Monoterpenos , Thymus (Planta) , Monoterpenos Acíclicos , Animais , Monoterpenos Cicloexânicos , Cimenos , DEET , Humanos , Óleos de Plantas , Timol
13.
J Agric Food Chem ; 52(2): 374-9, 2004 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-14733524

RESUMO

To determine the antioxidant effects of rice hull extract exposed to far-infrared radiation, the added extracts were compared with sesamol in cooked turkey breast. Rice hull extract showed antioxidant properties in cooked turkey breast by reducing lipid oxidation and volatile aldehydes. Far-infrared radiation increased significantly the antioxidant activities of rice hull extracts. Rice hull extract irradiated by far-infrared (FRH) had lower TBARS values and fewer volatile aldehydes (hexanal, pentanal, and propanal) than a non-irradiated extract (IRH) during the 3 days of aerobic storage. Addition of FRH at 0.2% (w/w) in turkey meat could reduce the amounts of volatile hexanal to 18-47% of the control during the storage. However, the antioxidant activities of rice hull extracts did not last as long as those of pure sesamol due to the relatively low concentration of phenolics, and the extracts had some peculiar odor. Addition of rice hull extracts also increased both a and b values of the samples due to its brown intensity.


Assuntos
Antioxidantes/farmacologia , Raios Infravermelhos , Carne/análise , Oryza/química , Sementes/química , Perus , Aldeídos/análise , Animais , Antioxidantes/análise , Benzodioxóis , Cor , Irradiação de Alimentos , Temperatura Alta , Peroxidação de Lipídeos/efeitos dos fármacos , Odorantes/análise , Fenóis/farmacologia , Extratos Vegetais/química , Substâncias Reativas com Ácido Tiobarbitúrico/análise
14.
J Agric Food Chem ; 51(15): 4400-3, 2003 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-12848517

RESUMO

After far-infrared (FIR) radiation onto rice hull, a methanolic extract was prepared for the determination of antioxidant ability. After 30 min of FIR treatment, the radical scavenging activity and total phenol contents of rice hull extracts increased from 47.74 to 79.63% and from 0.12 to 0.19 mM, respectively, compared to control. Inhibition of lipid peroxidation in extracts was also increased from 41.07 to 47.96%. According to the GC-MS analysis, more phenolic compounds (p-coumaric acid, 3-vinyl-1-oxybenzene, p-hydroxybenzaldehyde, vanillin, p-hydroxybenzoic acid, and 4,7-dihydroxyvanillic acid) were detected in FIR-irradiated rice hull extract. These results indicated that FIR radiation onto rice hull could liberate and activate covalently bound phenolic compounds that have antioxidant activities.


Assuntos
Antioxidantes/análise , Raios Infravermelhos , Oryza/química , Sementes/química , Antioxidantes/farmacologia , Sequestradores de Radicais Livres/análise , Cromatografia Gasosa-Espectrometria de Massas , Peroxidação de Lipídeos/efeitos dos fármacos , Fenóis/análise , Extratos Vegetais/química
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