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1.
J Food Sci Technol ; 56(5): 2501-2507, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31168132

RESUMO

Potato starch is an important agricultural product in Hokkaido, the northernmost island of Japan, with output of around 0.18 million tons/year. The present investigation was conducted to evaluate the physicochemical properties of potato starch samples manufactured in 10 factories in Hokkaido. The starch samples were analyzed for pasting properties by rapid visco analyzer (RVA), gelatinization properties by differential scanning calorimetry (DSC), color components, and minerals, amylose, and resistant starch (RS) contents. The phosphorus and potassium contents of potato starches averaged 746 ppm and 681 ppm, ranging from 669 to 835 ppm and from 481 to 803 ppm, respectively. Relatively wide ranges were noted in the contents of sodium (35-134 ppm), magnesium (50-121 ppm), and calcium (34-164 ppm). RVA analysis revealed clear differences in peak viscosity (PV) and breakdown (BD) among starch samples examined. Higher contents of divalent cations, magnesium, and calcium, were associated with lower values of PV and BD, whereas the phosphorus content did not affect PV and BD. The differences in amylose content, DSC gelatinization properties and color components as well as RS content in raw starch were not large.

2.
J Food Sci Technol ; 55(4): 1360-1365, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29606750

RESUMO

Iron fortification was applied to commercial potato starch by immersion in different concentrations of ferrous sulfate (FeSO4) aqueous solutions. To determine the impact of iron fortification on the properties of potato starch, all of the starches obtained through the process mentioned above were analyzed for their pasting properties, color, gelatinization properties, and resistant starch content. Results indicated that the iron content markedly increased from 16 to 890 ppm when the potato starch was treated with a FeSO4 aqueous solution. During iron fortification, pasting properties markedly changed. Peak viscosity and breakdown decreased while peak viscosity temperature increased with iron fortification. Iron fortification caused a little reduced whiteness (slightly lower L*-value) and enhanced yellowish color (higher b*-value). In contrast, iron fortification had little influence on the gelatinization temperature and enthalpy. Moreover, no significant change in the resistant starch content was observed due to iron fortification.

3.
Molecules ; 19(9): 14556-66, 2014 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-25225719

RESUMO

Calcium- and magnesium-fortified potato starches were prepared by immersion in various concentrations of CaCl2 and MgCl2 aqueous solutions, respectively. The pasting properties, i.e., peak viscosity and breakdown, of all the starches obtained above were analyzed using a Rapid Visco Analyzer. Furthermore, the gelatinization properties and in vitro digestibility of the representative calcium- and magnesium-fortified starches were tested. The maximum calcium content of the fortified potato starches was as high as 686 ppm with the addition of a high-concentration CaCl2 solution, while the calcium content of the control potato starch was 99 ppm. The magnesium content increased from 89 to 421 ppm by treatment of the potato starch with an MgCl2 solution. Markedly lower values of peak viscosity and breakdown were observed in calcium- and magnesium-fortified potato starches than in the control potato starch. However, the gelatinization temperature and enthalpy as well as resistant starch content of calcium- and magnesium-fortified potato starches were similar to those of the control potato starch. It is concluded that potato starches with altered pasting properties can be easily manufactured by the use of solutions containing high levels of calcium and magnesium.


Assuntos
Cálcio/química , Magnésio/química , Amido/química , Viscosidade , Amilose/química , Solanum tuberosum , Amido/síntese química , Temperatura
4.
Plant Foods Hum Nutr ; 65(3): 266-70, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20582572

RESUMO

Rats fed a diet containing Shadow Queen (SQ), an anthocyanin-rich potato cultivar, previously showed an increase in the hepatic superoxide dismutase (SOD)-2 mRNA level. We investigated whether an extract of SQ would directly increase the hepatic SOD-2 mRNA level in HepG2 cells. Furthermore, we estimated the intracellular signaling pathway for the induction of SOD-2 mRNA expression. HepG2 cells were stimulated using extracts of four crops, including SQ, for 12 h; only extracts of colored potatoes induced SOD-2 mRNA expression significantly. This induction of SOD-2 mRNA expression was blocked by an inhibitor of the extracellular signal-related kinase (ERK) 1/2 pathway. Furthermore, an extract of SQ increased the phosphorylation of ERK1/2 after 15 or 30 min of stimulation. These data indicate that an extract of SQ directly induces hepatic SOD-2 mRNA expression via activation of ERK1/2 pathway in HepG2 cells.


Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Preparações de Plantas/farmacologia , RNA Mensageiro/biossíntese , Solanum tuberosum , Superóxido Dismutase/biossíntese , Cruzamento , Células Hep G2 , Humanos , Fosforilação , Tubérculos , RNA Mensageiro/análise , Transdução de Sinais/efeitos dos fármacos , Solanum tuberosum/genética , Superóxido Dismutase/genética
5.
J Sci Food Agric ; 90(7): 1232-7, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20394006

RESUMO

BACKGROUND: Relationships between buckwheat (Fagopyrum esculentum Moench) flour lipase, lipoxygenase and peroxidase activity, along with levels of individual free fatty acids (FFAs) and levels of headspace volatile compounds of boiled buckwheat noodles, were investigated for 12 different buckwheat varieties. Enzyme activities and FFA levels in flour were correlated with their respective varietal arrays of boiled noodle headspace volatile compounds, measured by gas chromatography-mass spectrometry. RESULTS: The volatiles hexanal, tentative butanal, tentative 3-methylbutanal and tentative 2-methylbutanal showed significant positive correlation with one another, indicating that they may be generated through similar mechanisms. These important volatile components of buckwheat flavor were also positively correlated with lipase and/or peroxidase activity, indicating that enzymatic reactions are important in flavor generation in boiled buckwheat noodles. On the other hand, pentanal, which showed no significant correlation with any enzyme activity, showed a significant positive correlation to the levels of C18:2 and C18:3 FFAs, suggesting the existence of a 'non-enzymatic' and/or 'uncertain enzymatic pathway' for flavor generation in boiled buckwheat noodles. CONCLUSION: Lipase and peroxidase in buckwheat flour are important for flavor generation of boiled buckwheat noodles. This information is important for increasing desirable flavor of buckwheat products as well as for selecting varieties with improved flavor.


Assuntos
Enzimas/metabolismo , Fagopyrum/metabolismo , Ácidos Graxos não Esterificados/metabolismo , Análise de Alimentos , Proteínas de Plantas/metabolismo , Sementes/metabolismo , Compostos Orgânicos Voláteis/metabolismo , Fagopyrum/química , Fagopyrum/genética , Genótipo , Lipase/metabolismo , Lipoxigenase/metabolismo , Peroxidase/metabolismo , Sementes/genética , Sensação , Paladar
6.
Plant Foods Hum Nutr ; 64(3): 193-8, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19629697

RESUMO

To investigate whether yam improves glucose metabolism, yam-containing diets were given to Wistar rats. In a short-term experiment, fasted-rats were given 1.0 g of a control and 20% yam-containing diets. At 60 min after start of the feeding, glucose level in the yam diet group was lower or tended to be lower than that in the control diet. Insulin levels at 30 min and 60 min were significantly lower than those in the control group. In a long-term experiment, a normal diet (N) or 25% high fat diets with (Y) or without 15% yam powder (HF) were given to rats for 4 weeks. At 4 weeks, in an oral glucose tolerance test, the area under the curve (AUC) of plasma glucose level was higher in the HF group than that in the N group, whereas those in the Y groups did not differ from that in the N group. Glycosylated hemoglobin levels had similar tendency to the AUCs. Plasma leptin levels in the Y groups were significantly higher than that in the N group. In conclusion, yam may contribute to improvement of glucose metabolism. Additionally, we speculated that leptin level is possibly involved in the insulin-response to yam diets.


Assuntos
Glicemia/metabolismo , Dioscorea , Hemoglobinas Glicadas/metabolismo , Insulina/sangue , Leptina/sangue , Preparações de Plantas/farmacologia , Animais , Área Sob a Curva , Culinária , Dieta , Gorduras na Dieta/administração & dosagem , Teste de Tolerância a Glucose , Masculino , Pós , Ratos , Ratos Wistar
7.
J Agric Food Chem ; 57(1): 259-64, 2009 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-19090759

RESUMO

Concentrations of gamma-aminobutyric acid (GABA), rutin, minor flavonoids (such as orientin), anthocyanin, and 2''-hydroxynicotianamine (2HN) were quantified in the leaves of common and tartary buckwheat (Fagopyrum esculentum Moench and Fagopyrum tataricum Gaertn., respectively), at 14, 28, and 42 days after sowing (DAS). GABA and rutin concentrations peaked at 42 DAS, whereas anthocyain, 2HN, and minor flavonoid concentrations declined with the age of the plants. However, at 42 DAS, anthocyanin concentrations in the leaves of tartary buckwheat Hokkai T10 leaves were at least 10-fold greater than in the other buckwheats tested. In addition, the effects on target compound concentrations and 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity of three different drying methods (20 h at 40 degrees C, 7 h at 70 degrees C, or lyophilization) were investigated. In general, the drying method had no significant effect on the parameters tested. These results indicate that, in terms of GABA, rutin, and anthocyanin concentrations, leaf powder from 42 day old Hokkai T10 has the potential to be a useful food ingredient, such as Ao-jiru juice.


Assuntos
Antocianinas/análise , Ácido Azetidinocarboxílico/análogos & derivados , Dessecação/métodos , Fagopyrum/química , Flavonoides/análise , Ácido gama-Aminobutírico/análise , Ácido Azetidinocarboxílico/análise , Sequestradores de Radicais Livres/análise , Cinética , Folhas de Planta/química , Rutina/análise
8.
Food Chem ; 110(4): 814-20, 2008 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-26047265

RESUMO

The phenolic compositions of non-germinated/germinated seeds and seed sprouts (at 6-10 day-old) of common (Fagopyrum esculentum Möench) and tartary (Fagopyrum tataricum Gaertn.) buckwheats were investigated. Phenolic compounds, including chlorogenic acid, four C-glycosylflavones (orientin, isoorientin vitexin, isovitexin), rutin and quercetin, were determined in the seed sprouts by high-performance liquid chromatography (HPLC). In the edible parts of common buckwheat sprouts, individual phenolics significantly increased during sprout growth from 6 to 10 days after sowing (DAS), whereas in tartary buckwheat sprouts they did not. While the sum contents of phenolic compounds in the edible part (mean 24.4mg/g DW at 6-10 DAS) of tartary buckwheat sprouts were similar to those of common buckwheat sprouts, rutin contents in the non-germinated/germinated seeds (mean 14.7mg/g DW) and edible parts (mean 21.8mg/g DW) of tartary buckwheat were 49- and 5-fold, respectively, higher than those of common buckwheat. Extracts of the edible parts of both species showed very similar free radical-scavenging activities (mean 1.7µmol trolox eq/g DW), suggesting that the overall antioxidative activity might be affected by the combination of identified phenolics and unidentified (minor) components. Therefore, buckwheat seed sprouts are recommended for their high antioxidative activity, as well as being an excellent dietary source of phenolic compounds, particularly tartary buckwheat sprouts, being rich in rutin.

9.
Can J Anaesth ; 54(12): 998-1005, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18056209

RESUMO

PURPOSE: gamma-Aminobutyric acid (GABA) and N-methyl-D-aspartate (NMDA) receptors are important targets for anesthetic action at the in vitro cellular level. Gabaculine is a GABA-trans-aminase inhibitor that increases endogenous GABA in the brain, and enhances GABA activity. We have recently shown that unconsciousness is associated with the enhanced GABA activity due to gabaculine, but that immobility is not. MK-801 is a selective NMDA channel blocker. In this study, we examined behaviourally whether gabaculine in combination with MK-801 could produce these components of the general anesthetic state. We further compared the effect of MK-801 with ketamine, another NMDA channel blocker. METHODS: All drugs were administered intraperitoneally to adult male ddY mice. To assess the general anesthetic components, two endpoints were used. One was loss of the righting reflex (LORR; as a measure of unconsciousness) and the other was loss of movement in response to tail-clamp stimulation (as a measure of immobility). RESULTS: Large doses of MK-801 alone (10-50 mg.kg(-1)) induced neither LORR nor immobility in response to noxious stimulation. However, even a small dose (0.2 mgxkg(-1)) significantly enhanced gabaculine-induced LORR (P < 0.05), although gabaculine in combination with MK-801 (0.2-10 mgxkg(-1)) produced no immobility. However, gabaculine plus a subanesthetic dose of ketamine (30 mgxkg(-1)), which acts on NMDA, opioid and nicotinic acetylcholine receptors and neuronal Na(+) channels, suppressed the pain response, but did not achieve a full effect. Ketamine alone dose-dependently produced both LORR and immobility. CONCLUSION: These findings suggest that gabaculine-induced LORR is modulated by blocking NMDA receptors, but that immobility is not mediated through GABA or NMDA receptors.


Assuntos
Ácidos Cicloexanocarboxílicos/farmacologia , Maleato de Dizocilpina/farmacologia , Inibidores Enzimáticos/farmacologia , Movimento/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Reflexo/efeitos dos fármacos , Anestesia Geral , Animais , Sinergismo Farmacológico , Masculino , Camundongos , Receptores de GABA/efeitos dos fármacos , Receptores de GABA/fisiologia , Receptores de N-Metil-D-Aspartato/efeitos dos fármacos , Receptores de N-Metil-D-Aspartato/fisiologia
10.
J Agric Food Chem ; 55(23): 9571-5, 2007 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-17941697

RESUMO

The anthocyanin profiles and variety/breeding-line differences of anthocyanin concentrations in petals of common buckwheat flowers have been studied. Four anthocyanins, cyanidin 3-O-glucoside, cyanidin 3-O-rutinoside, cyanidin 3-O-rhamnoside, and cyanidin 3-O-galactosyl-rhamnoside were isolated from the petals of common buckwheat (Fagopyrum esculentum Moench), separated using high performance liquid chromatography and identified using reversed-phase liquid chromatography-electrospray ionization-tandem mass spectrometry techniques. In every variety/breeding line tested, cyanidin 3-O-rutinoside was detected as the major anthocyanin and the next is cyanidin 3-O-glucoside whereas cyanidin 3-O-rhamnoside and cyanidin 3-O-galactosyl-rhamnoside were trace or not detectable in white and pink flowered buckwheat. Of all the varieties/breeding lines tested, Gan-Chao, a Chinese variety, contained the highest amount of anthocyanins. The largest part of cyanidin moiety was presented as a proanthocyanidin form (PAs-Cy). Anthocyanins and PAs-Cy in petals were increased along with increase of flower development stages. Therefore, fully developed petals of red flowered buckwheat, especially Gan-Chao, are promising as a new anthocyanin-rich material for food processing.


Assuntos
Antocianinas/análise , Antocianinas/química , Fagopyrum , Flores/química , Flores/crescimento & desenvolvimento , Fagopyrum/química , Fagopyrum/crescimento & desenvolvimento
11.
J Agric Food Chem ; 55(15): 6314-8, 2007 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-17580874

RESUMO

The anthocyanin profiles and varieties/breeding line differences of anthocyanin concentrations in common/tartary buckwheat sprouts have been studied. Four anthocyanins, cyanidin 3-O-glucoside, cyanidin 3-O-rutinoside, cyanidin 3-O-galactoside, and cyanidin 3-O-galactopyranosyl-rhamnoside, were isolated from the sprouts of common buckwheat, were separated using high-performance liquid chromatography (HPLC), and were identified using reversed-phase liquid chromatography (LC)/electrospray ionization-mass spectrometry (ESI-MS)/MS techniques. In tartary buckwheat sprouts, two anthocyanins (cyanidin 3-O-glucoside and cyanidin 3-O-rutinoside) were identified. Among 19 common/tartary buckwheat varieties/breeding lines, Hokkai T10 contained the highest amounts of anthocyanins. Cyanidin 3-O-glucoside and cyanidin 3-O-rutinoside concentrations in 6-10 days after seeding sprouts of Hokkai T10 ranged from 0.16 to 0.20 mg/g dry wt and from 5.55 to 6.57 mg/g dry wt, respectively. In addition, dark-grown sprouts of Hokkai T10 accumulated 0.091 and 2.77 mg/g dry wt of cyanidin 3-O-glucoside and cyanidin 3-O-rutinoside whereas other varieties/breeding lines accumulated trace amounts of anthocyanins. Given its anthocyanin-rich red cotyledons, Hokkai T10 is a promising line for use as "Moyashi" type sprouts and is strongly recommended as a new functional food, rich in dietary anthocyanins.


Assuntos
Antocianinas/análise , Fagopyrum/química , Plântula/química , Antocianinas/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Especificidade da Espécie , Espectrometria de Massas por Ionização por Electrospray , Fatores de Tempo
12.
Anesth Analg ; 104(6): 1415-21, table of contents, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17513634

RESUMO

BACKGROUND: The general anesthetic state comprises behavioral and perceptual components, including amnesia, unconsciousness, analgesia, and immobility. In vitro, glutamatergic excitatory neurons are important targets for anesthetic action at the cellular and microcircuits levels. Riluzole (2-amino-6-[trifluoromethoxy]benzothiazole) is a neuroprotective drug that inhibits glutamate release from nerve terminals in the central nervous system. Here, we examined in vivo the ability of riluzole to produce components of the general anesthetic state through a selective blockade of glutamatergic neurotransmission. METHODS: Riluzole was administered intraperitoneally in adult male ddY mice. To assess the general anesthetic components, three end-points were used: 1) loss of righting reflex (LORR; as a measure of unconsciousness), 2) loss of movement in response to noxious stimulation (as a measure of immobility), and 3) loss of nociceptive response (as a measure of analgesia). RESULTS: The intraperitoneal administration of riluzole induced LORR in a dose-dependent fashion with a 50% effective dose value of 27.4 (23.3-32.2; 95% confidence limits) mg/kg. The behavioral and microdialysis studies revealed that time-course changes in impairment and LORR induced by riluzole corresponded with decreased glutamate levels in the mouse brain. This suggests that riluzole-induced LORR (unconsciousness) could result, at least in part, from its ability to decrease brain glutamate concentrations. Riluzole dose-dependently produced not only LORR, but also loss of movement in response to painful stimulation (immobility), and loss of nociceptive response (analgesia) with 50% effective dose values of 43.0 (37.1-49.9), and 10.0 (7.4-13.5) mg/kg, respectively. These three dose-response curves were parallel, suggesting that the behavioral effects of riluzole may be mediated through a common site of action. CONCLUSIONS: These findings suggest that riluzole-induced LORR, immobility, and antinociception appear to be associated with its ability to inhibit glutamatergic neurotransmission in the central nervous system.


Assuntos
Analgésicos/farmacologia , Ácido Glutâmico/metabolismo , Imobilização , Medição da Dor/efeitos dos fármacos , Reflexo/efeitos dos fármacos , Riluzol/farmacologia , Analgésicos/uso terapêutico , Animais , Relação Dose-Resposta a Droga , Imobilização/métodos , Masculino , Camundongos , Movimento/efeitos dos fármacos , Dor/tratamento farmacológico , Medição da Dor/métodos , Estimulação Física/efeitos adversos , Estimulação Física/métodos , Reflexo/fisiologia , Riluzol/uso terapêutico
13.
Anesth Analg ; 104(6): 1422-9, table of contents, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17513635

RESUMO

BACKGROUND: The general anesthetic state comprises behavioral and perceptual components, including amnesia, unconsciousness, and immobility. gamma-Aminobutyric acidergic (GABAergic) inhibitory neurotransmission is an important target for anesthetic action at the in vitro cellular level. In vivo, however, the functional relevance of enhancing GABAergic neurotransmission in mediating essential components of the general anesthetic state is unknown. Gabaculine is a GABA-transaminase inhibitor that inhibits degradation of released GABA, and consequently increases endogenous GABA in the central nervous system. Here, we examined, behaviorally, the ability of increased GABA levels to produce components of the general anesthetic state. METHODS: All drugs were administered systemically in adult male ddY mice. To assess the general anesthetic components, two end-points were used. One was loss of righting reflex (LORR; as a measure of unconsciousness); the other was loss of movement in response to tail-clamp stimulation (as a measure of immobility). RESULTS: Gabaculine induced LORR in a dose-dependent fashion with a 50% effective dose of 100 (75-134; 95% confidence limits) mg/kg. The behavioral and microdialysis studies revealed that the endogenous GABA-induced LORR occurred in a brain concentration-dependent manner. However, even larger doses of gabaculine (285-400 mg/kg) produced no loss of tail-clamp response. In contrast, all the tested volatile anesthetics concentration-dependently abolished both righting and tail-clamp response, supporting the evidence that volatile anesthetics act on a variety of molecular targets. CONCLUSIONS: These findings indicate that LORR is associated with enhanced GABAergic neurotransmission, but that immobility in response to noxious stimulation is not, suggesting that LORR and immobility are mediated through different neuronal pathways and/or regions in the central nervous system.


Assuntos
Encéfalo/metabolismo , Imobilização , Reflexo/fisiologia , Ácido gama-Aminobutírico/biossíntese , Animais , Encéfalo/efeitos dos fármacos , Ácidos Cicloexanocarboxílicos/farmacologia , Relação Dose-Resposta a Droga , Imobilização/métodos , Masculino , Camundongos , Estimulação Física/métodos , Reflexo/efeitos dos fármacos , Ácido gama-Aminobutírico/metabolismo
14.
Anesth Prog ; 54(1): 2-6, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17352526

RESUMO

Monitoring and assessing of patient respiratory function during conscious sedation are important because many drugs used for conscious sedation produce respiratory depression and subsequent hypoventilation. The purpose of this study is to assess the value of a dynamic air-pressure sensor for respiratory monitoring of clothed patients. Eight clothed adult volunteers were reclined on a dental chair positioned horizontally. The air bag for measuring air-pressure signals corresponding to respiration was placed on the seat back of the dental chair in the central lumbar area of the subject. The subject breathed through a face mask with a respirometer attached for measuring expiratory tidal volume. The air-pressure signals corresponding to respiration were obtained and the time integration values for air pressure during each expiration (integral P(exp)) were calculated. The expiratory tidal volume (TV(exp)) was measured simultaneously by respirometer. The relationship between TV(exp) and integral P(exp) for each subject was assessed by a Pearson correlation coefficient. A strong correlation between TV(exp) and integral P(exp) was observed in all subjects. Measuring integral P(exp) by dynamic air-pressure sensor makes it possible to estimate respiratory volume breath by breath, and the respiratory pressure-time integral waveform was useful in visually monitoring the respiration pattern. We believe that in the future this device will be used to monitor respiratory physiology in clothed patients, contributing to safer sedative procedures.


Assuntos
Monitorização Fisiológica/instrumentação , Respiração , Adulto , Pressão do Ar , Desenho de Equipamento , Expiração/fisiologia , Feminino , Humanos , Masculino , Máscaras , Espirometria/instrumentação , Volume de Ventilação Pulmonar/fisiologia , Transdutores de Pressão
15.
Biosci Biotechnol Biochem ; 70(5): 1173-80, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16717419

RESUMO

To clarify the effects of storage temperature on potato components and acrylamide in chips, tubers from five cultivars were stored at various temperatures (2, 6, 8, 10, and 18 degrees C) for 18 weeks, and the contents of sugars, free amino acids in tubers, and acrylamide in chips after frying were analyzed. At temperatures lower than 8 degrees C, the contents of reducing sugars increased markedly in all cultivars, with similar increases in the acrylamide level and dark brown chip color. Free amino acids showed little change at the storage temperatures tested and varied within certain ranges characteristic of each cultivar. The contents of reducing sugars correlated well with the acrylamide level when the fructose/asparagine molar ratio in the tubers was <2. When the fructose/asparagine ratio was >2 by low-temperature storage, the asparagine content, rather than the reducing sugar content, was found to be the limiting factor for acrylamide formation.


Assuntos
Acrilamida/análise , Aminoácidos/análise , Carboidratos/análise , Manipulação de Alimentos , Solanum tuberosum/química , Temperatura , Análise de Alimentos , Frutose/análise , Tubérculos/química
16.
Biosci Biotechnol Biochem ; 69(7): 1232-8, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16041124

RESUMO

Changes in the sugar and amino acid contents of potato tubers during short-term storage and the effect on the acrylamide level in chips after frying were investigated. The acrylamide content in chips began to increase after 3 days of storage at 2 degrees C in response to the increase of glucose and fructose contents in the tubers. There was strong correlation between the reducing sugar content and acrylamide level, R(2)=0.873 for fructose and R(2)=0.836 for glucose. The sucrose content had less correlation with the acrylamide content because of its decrease after 4 weeks of storage at 2 degrees C, while the reducing sugar in potato tubers and the acrylamide in chips continued to increase. The contents of the four amino acids, i.e., asparatic acid, asparagine, glutamic acid and glutamine, showed no significant correlation with the acrylamide level. These results suggest that the content of reducing sugars in potato tubers determined the degree of acrylamide formation in chips. The chip color, as evaluated by L* (lightness), was correlated well with the acrylamide content.


Assuntos
Acrilamida/metabolismo , Aminoácidos/metabolismo , Metabolismo dos Carboidratos , Culinária/métodos , Solanum tuberosum/química , Asparagina/análise , Ácido Aspártico/análise , Cromatografia Líquida de Alta Pressão , Temperatura Baixa , Cor , Manipulação de Alimentos/métodos , Conservação de Alimentos/métodos , Frutose/análise , Glucose/análise , Ácido Glutâmico/análise , Glutamina/análise , Fatores de Tempo
17.
Adv Exp Med Biol ; 561: 405-13, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16438315

RESUMO

Acrylamide concentrations in processed foods sold in Japanese markets were analyzed by LC-MS/MS and GC-MS methods. Most potato chips and whole potato-based fried snacks showed acrylamide concentration higher than 1000 microg/kg. The concentrations in non-whole potato based Japanese snacks, including rice crackers and candied sweet potatoes, were less tha. 350 microg/kg. Those in instant precooked noodles were less than 100 microg/kg with only one exception. The effect of storage condition of potato tubers on acrylamide concentration in potato chips after frying was also investigated. Sugar content in the tubers increased during cold storage, and the acrylamide concentration increased accordingly. The concentrations of asparagine and other amino acids, however, did not change during the cold storage. High correlations were observed between the acrylamide content in the chips and glucose and fructose contents in the tubers. This fact indicated that the limiting factor for acrylamide formation in potato chips is reducing sugar, not asparagine content in the tubers. Effects of roasting time and temperature on acrylamide concentration in roasted green tea are also described.


Assuntos
Acrilamida/análise , Manipulação de Alimentos/métodos , Solanum tuberosum/química , Acrilamidas/análise , Asparagina/química , Cromatografia Líquida , Culinária , Análise de Alimentos , Contaminação de Alimentos , Conservação de Alimentos , Frutose/análise , Cromatografia Gasosa-Espectrometria de Massas , Glucose/análise , Japão , Espectrometria de Massas , Modelos Químicos , Chá , Temperatura , Fatores de Tempo
18.
Pediatr Int ; 46(4): 387-93, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15310300

RESUMO

BACKGROUND: The presence of bone marrow (BM) metastasis and circulating tumor cells in patients with neuroblastoma is a significant prognostic factor at diagnosis and might antedate detection of a relapse by other diagnostic studies. In this study, the clinical value of reverse transcription-polymerase chain reaction (RT-PCR) to amplify mRNA for tyrosine hydroxylase (TH) and magnetic resonance imaging (MRI) during the clinical course of patients with advanced neuroblastoma, was evaluated. METHODS: Four patients with Stage 1, 4 or 4S neuroblastoma, were studied. BM and peripheral blood (PB), including peripheral blood stem cell (PBSC), samples were examined for TH mRNA using RT-PCR. Concurrently, MRI detection of BM metastasis was used. RESULTS: In all cases, except one that had no evidence of BM invasion, TH mRNA in BM and PB at diagnosis were positive, and TH mRNA at diagnosis disappeared after chemotherapy. In two cases, although involvement in the neurocentrum BM was detected by MRI, TH mRNA in the iliac crest BM was negative. The pathological area still remained on MRI after intensive therapy. CONCLUSION: RT-PCR for TH mRNA might be the most sensitive method for the detection of occult neuroblastoma cells in BM and PB. However, because invasion of the BM by neuroblastoma may have a focal distribution, sampling errors can occur. Therefore, not only RT-PCR but also MRI, need to be used to rule out marrow involvement, especially at diagnosis and BM relapse.


Assuntos
Neoplasias da Medula Óssea/diagnóstico , Neuroblastoma/patologia , Tirosina 3-Mono-Oxigenase/genética , Adolescente , Adulto , Medula Óssea/enzimologia , Medula Óssea/metabolismo , Medula Óssea/patologia , Neoplasias da Medula Óssea/metabolismo , Feminino , Humanos , Lactente , Imageamento por Ressonância Magnética , Masculino , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Radiografia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Coluna Vertebral/diagnóstico por imagem , Coluna Vertebral/patologia
19.
J Plant Res ; 117(2): 131-7, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-14986152

RESUMO

The storage of potato tubers at low temperatures leads to the accumulation of sugars in a process called "low-temperature sweetening." To understand this phenomenon, we measured the sugar contents and the activity of acid invertase over several months in tubers of six Japanese cultivars stored at 4 degrees C or 20 degrees C. At 20 degrees C, few changes in sugar contents took place in any of the tubers. On the other hand, when stored at 4 degrees C, three types of changes were observed among the cultivars: (1) increased levels of reducing sugars during storage; (2) a pattern similar to that of type 1, but with 4- to 6-fold lower levels of reducing sugars throughout storage; and (3) increased sucrose, but not reducing sugars. The activity of vacuolar acid invertase increased in the type-1 cultivars, whereas, in the type-2 and type-3 cultivars, the activities were very low during storage at 4 degrees C. Reverse transcription-polymerase chain reaction analysis of acid invertase showed that the transcripts of the enzyme accumulated in the tubers stored at 4 degrees C in the type-1 cultivars but not in type-3. These results suggest that the activity of vacuolar acid invertase is related to the types of changes that occurred in sugar content during low-temperature storage among the potato cultivars.


Assuntos
Temperatura Baixa , Manipulação de Alimentos , Conservação de Alimentos , Frutose/análise , Glucose/análise , Solanum tuberosum/química , beta-Frutofuranosidase/metabolismo , Solanum tuberosum/enzimologia
20.
No To Hattatsu ; 35(5): 411-6, 2003 Sep.
Artigo em Japonês | MEDLINE | ID: mdl-13677951

RESUMO

We report a 3-year-old girl with idiopathic hypereosinophilic syndrome. She was admitted to our hospital because of fever, cough, significant eosinophilia (16,500/microliter) and an elevated serum IgE level (114,685 u/ml). After wheezes continued for several days, paraplegia, dysuria and dyschezia developed. CSF, chest roentgenogram and spinal MRI were normal, as well as motor and sensory conduction velocities of the median and tibial nerves. Flaum's hematologic score was 4. Treatment with prednisolone resulted in remission of neurological symptoms and a rapidly normalization of the eosinophil count. During the following months, eosinophilia reappeared with tapering the medication, but there was no recurrence of neurological signs. Glucocorticoid therapy was discontinued after 21 months.


Assuntos
Síndrome Hipereosinofílica/etiologia , Paraplegia/etiologia , Pré-Escolar , Eosinófilos , Feminino , Humanos , Síndrome Hipereosinofílica/sangue , Síndrome Hipereosinofílica/diagnóstico , Síndrome Hipereosinofílica/tratamento farmacológico , Imunoglobulina E/sangue , Contagem de Leucócitos , Paraplegia/tratamento farmacológico , Prednisolona/administração & dosagem , Fatores de Tempo
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