RESUMEN
Potato chips (PC) contain abundant amounts of the free radical scavenger ascorbic acid (AA) due to the rapid dehydration of potato tubers (Solanum tuberosum) that occurs during frying. To evaluate the antioxidant activity of PC, this study examined reactive oxygen species (ROS) levels in tissues from SMP30/GNL knockout (KO) mice that cannot synthesize AA and determined AA and ROS levels after the animals were fed 20 and 10% PC diets for 7 weeks. Compared with AA-sufficient mice, AA-depleted SMP30/GNL KO mice showed high ROS levels in tissues. SMP30/GNL KO mice fed a PC diet showed high AA and low ROS levels in the brain, heart, lung, testis, soleus muscle, plantaris muscle, stomach, small intestine, large intestine, eyeball, and epididymal fat compared with AA-depleted mice. The data suggest that PC intake increases AA levels and enhances ROS scavenging activity in tissues of SMP30/GNL KO mice, which are a promising model for evaluating the antioxidant activity of foods.
Asunto(s)
Ácido Ascórbico/metabolismo , Proteínas de Unión al Calcio/metabolismo , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Solanum tuberosum/metabolismo , Alimentación Animal/análisis , Animales , Encéfalo/metabolismo , Hígado/metabolismo , Pulmón/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Tubérculos de la Planta/química , Tubérculos de la Planta/metabolismo , Solanum tuberosum/química , Testículo/metabolismoRESUMEN
Potato (Solanum tuberosum) tubers contain vitamin C (VC) and commercial potato chips have more VC content per wet weight by dehydration during frying. However, intestinal absorption of VC from orally ingested potatoes and its transfer to the blood remains questionable. The present study was designed to determine whether the dietary consumption of potatoes affects VC concentration in plasma and urinary excretion of VC in human subjects. After overnight fasting, five healthy Japanese men between 22 and 27 years of age consumed 87 g mashed potatoes and 282 g potato chips. Each portion contained 50 mg of VC, 50 mg VC in mineral water and mineral water. Before and after a single episode of ingestion, blood and urine samples were collected every 30 min or 1 h for 8 h. When measured by subtraction of the initial baseline value before administration of potatoes from the values measured throughout the 8 h test period, plasma VC concentrations increased almost linearly up to 3 h. Subsequently, the values of potato-fed subjects were higher than those of water, but did not differ significantly from those of VC in water (P = 0·14 and P = 0·5). Less VC tended to be excreted in urine during the 8 h test than VC in water alone (17·0 (sem 7·5) and 25·9 (sem 8·8) v. 47·9 (sem 17·9) µmol/mmol creatinine). Upon human consumption, mashed potatoes and potato chips provide VC content that is effectively absorbed in the intestine and transferred to the blood. Clearly, potatoes are a readily available source of dietary VC.
Asunto(s)
Ácido Ascórbico/metabolismo , Comida Rápida/análisis , Manipulación de Alimentos , Tubérculos de la Planta/química , Solanum tuberosum/química , Adulto , Ácido Ascórbico/análisis , Ácido Ascórbico/sangre , Ácido Ascórbico/orina , Estudios de Cohortes , Culinaria , Estudios Cruzados , Humanos , Japón , Cinética , Masculino , Valor Nutritivo , Adulto JovenRESUMEN
We evaluated the antioxidative activity of a water soluble polysaccharide fraction (WSP) from pumpkin fruits (Cucurbita maxima Duchesne). In the WSP, DPPH radical scavenging and superoxide dismutase-like activity increased depending on the total sugar content. Furthermore, the WSP can serve as an inhibitor of ascorbic acid oxidation. The efficacy was also affected by the total sugar content.
Asunto(s)
Antioxidantes/farmacología , Polisacáridos/farmacología , Cucurbita , Solubilidad , Espectrofotometría Ultravioleta , AguaRESUMEN
Acrylamide (AAm) is produced in food through the reaction of asparagine and reducing sugar. We examined several methods of reducing the level of AAm using potato tubers. The fried model system that we employed consisted of thin slices that were first treated in water under different conditions before frying. A sufficient amount of water present in the fry material acts as an inhibitor against the formation of AAm and allows only a negligible amount of AAm to form. It was found that given the low content of water, the fry material temperature was sufficiently high to allow a relatively large level of AAm to form. Examination of water treatment prior to frying revealed that higher-temperature treatment water and longer treatment time resulted in the formation of lower levels of AAm. Moreover, removing some of the residual heat had an inhibiting effect on the formation of AAm.
Asunto(s)
Acrilamida/química , Manipulación de Alimentos , Tubérculos de la Planta/química , Solanum tuberosum/química , Asparagina/química , Carbohidratos/química , Temperatura , Agua/químicaRESUMEN
Free and bound-form phenolics were isolated from potato (cv. Toyoshiro) flesh and peel. The free and bound-form phenolics in the peel showed high DPPH radical scavenging activity, while those in the flesh showed low activity. The total amount of chlorogenic acid and caffeic acid in the free-form phenolics from the peel was highly correlated with the DPPH radical scavenging activity. Ferulic acid was identified as the active radical scavenging compound in the bound-form phenolics from the peel. The potato peel may therefore offer an effective source of an antioxidative.
Asunto(s)
Antioxidantes/química , Antioxidantes/farmacología , Fenoles/química , Fenoles/farmacología , Solanum tuberosum/química , Antioxidantes/aislamiento & purificación , Compuestos de Bifenilo , Cromatografía Líquida de Alta Presión , Radicales Libres/química , Fenoles/aislamiento & purificación , Picratos/químicaRESUMEN
Acrylamide (AAm) is formed from asparagine (Asn) and reducing sugar during cooking of foods at high temperature. We examined the formation of AAm in a model system using a glass fiber filter paper, and looked for suitable conditions for inhibiting AAm formation. In frying, the formation rate was about 10 times that in a moistureless oven. Increase of frying temperature and frying time increased AAm formation when the residual moisture was 5% or less. AAm increased with increasing amount of glucose (Glc) addition up to 1:1 with respect to Asn, but then decreased. On the other hand, in the case of fructose, as the amount added was increased, AAm increased accordingly. The AAm formation rate with respect to Asn increased when valine (Val) was co-present in a Glc and Asn reaction system. Cysteine and lysine inhibited the AAm formation rate. Pathways for the formation of AAm are proposed.