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1.
Biosci Biotechnol Biochem ; 77(5): 984-7, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23649258

RESUMEN

Xanthone compounds in mangosteen (Garcinia mangostana Linn.) fruit have been reported to have biological activities including antioxidative and anti-inflammatory effects, and the major xanthone compounds in mangosteen are α-mangostin and γ-mangostin. The objectives of this research were to quantify and qualify the major xanthones in each part of the mangosteen fruit with and without yellow gum from the point of view of effective utilization of agricultural product. Quantitative evaluation revealed that yellow gum had extremely high amounts of α-mangostin and γ-mangostin (382.2 and 144.9 mg/g on a wet basis, respectively) followed by pericarp and aril. In mangosteen fruit with yellow gum inside, xanthones seemed to have shifted from the pericarp and to have concentrated in a gum on the surface of aril, and there was almost no difference between the amounts of α-mangostin and γ-mangostin in whole fruits with and without yellow gum. Pericarp and yellow gum showed much higher radical-scavenging activity and ferric reducing antioxidant potential than the aril.


Asunto(s)
Antioxidantes/metabolismo , Antioxidantes/farmacología , Frutas/anatomía & histología , Frutas/metabolismo , Garcinia mangostana/metabolismo , Xantonas/metabolismo , Xantonas/farmacología , Antioxidantes/aislamiento & purificación , Xantonas/aislamiento & purificación
2.
Mycopathologia ; 172(4): 323-30, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21424857

RESUMEN

The occurrence of mycotoxins in small grain cereals and their retention in final products are serious concerns for food safety. Previously, we investigated the fate of deoxynivalenol and nivalenol in a Japanese soft red winter wheat cultivar during milling and we found that deoxynivalenol and/or nivalenol was readily distributed among flours for human consumption. In the present study, we analyzed the ergosterol concentrations in the milling fractions as an index of fungal biomass to elucidate the relationship between deoxynivalenol/nivalenol accumulation and fungal invasion into the grain, after the in-house validation of an analytical method for quantifying ergosterol in the resulting milling fractions (patent flour, low-grade flour, bran, and shorts). Using three samples with different levels of deoxynivalenol and/or nivalenol contamination, the contents of deoxynivalenol/nivalenol and ergosterol in the resulting milling fractions were evaluated. The concentration of ergosterol was always lowest in patent flour and highest in bran or shorts, indicating that most of the fungi is retained in the outer layers of grain (bran and shorts) even in highly contaminated grain. On the other hand, the concentrations of deoxynivalenol and nivalenol were similar in the low-grade and patent flours and only slightly lower than in the medium-level and high-level contaminated grains. Moreover, the percentage distribution of ergosterol was higher in bran than in other fractions in all cases, which differed from that of deoxynivalenol/nivalenol. This result indicates the diffusion of deoxynivalenol/nivalenol inside the grain that is independent of fungal invasion.


Asunto(s)
Ergosterol/análisis , Microbiología de Alimentos , Fusarium/crecimiento & desarrollo , Tricotecenos/análisis , Triticum/química , Triticum/microbiología
3.
Biocontrol Sci ; 16(2): 79-83, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21719994

RESUMEN

The decontamination effect of milling by a jet mill was investigated by counting the number of bacteria in brown and white rice flour with mean particle diameters of 3, 20, and 40µm prepared by the jet mill. In the jet mill, the particles are crushed and reduced in size by the mechanical impact caused by their collision. Although the brown and white rice grains were contaminated with approximately 10(6) and 10(5) CFU/g bacteria, the microbial load of the rice flour decreased as the mean particle diameter decreased, ultimately decreasing to approximately 104 and 103 CFU/g in the brown and white rice flour. The temperature and pressure changes of the sample were not considered to have an effect on reducing the bacterial count during the milling. Hence, it was thought that the rice flour was decontaminated by other effects.


Asunto(s)
Descontaminación/métodos , Harina/microbiología , Manipulación de Alimentos/métodos , Microbiología de Alimentos/métodos , Oryza/microbiología , Carga Bacteriana , Descontaminación/instrumentación , Diseño de Equipo , Manipulación de Alimentos/instrumentación , Microbiología de Alimentos/instrumentación , Oryza/química , Tamaño de la Partícula , Semillas/química , Semillas/microbiología
4.
J Food Prot ; 73(10): 1817-23, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21067669

RESUMEN

The fate of the Fusarium mycotoxins deoxynivalenol and nivalenol during the milling of Japanese wheat cultivars artificially infected with Fusarium was investigated. Grain samples with different mycotoxin concentrations were milled using a laboratory-scale test mill to produce eight fractions: three breaking flours (1B, 2B, and 3B), three reduction flours (1M, 2M, and 3M), wheat bran, and wheat shorts. Patent flour for human consumption was made from the 1B, 2B, 1M, and 2M flours, and low-grade flour was made from 3B and 3M flours. The four resulting samples (patent flour, low-grade flour, bran, and shorts) were analyzed for deoxynivalenol and/or nivalenol with an in-house validated analytical method using high-performance liquid chromatography with UV absorbance detection. In samples with different mycotoxin concentrations, the distribution of those toxins differed among the milling fractions. Grains with a lower level of contamination produced bran and shorts samples with a high relative concentration of nivalenol. A high percentage of nivalenol was found in patent flour, followed by bran. Contrary to the less-contaminated sample, the concentration of nivalenol in moderately contaminated grain was high only in the shorts sample. The highest percentage of deoxynivalenol and nivalenol was observed in the patent flour. The results of this study indicate that the distribution of deoxynivalenol and nivalenol in milled Japanese wheat could be influenced by the contamination level of the original grain, and the milling process is not always effective for removal of toxins from wheat grains.


Asunto(s)
Contaminación de Alimentos/análisis , Manipulación de Alimentos/métodos , Fusarium/metabolismo , Tricotecenos/análisis , Triticum , Cromatografía Líquida de Alta Presión , Seguridad de Productos para el Consumidor , Harina/análisis , Fusarium/crecimiento & desarrollo , Humanos , Tricotecenos/biosíntesis , Triticum/química , Triticum/microbiología
5.
Biosci Biotechnol Biochem ; 73(7): 1671-3, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19584528

RESUMEN

The possibility of using two kinds of sorghum as raw materials in consolidated bioprocessing bioethanol production using Flammulina velutipes was investigated. Enzymatic saccharification of sweet sorghum was not as high as in brown mid-rib (bmr) mutated sorghum, but the amount of ethanol production was higher. Ethanol production from bmr mutated sorghum significantly increased when saccharification enzymes were added to the culture.


Asunto(s)
Fuentes de Energía Bioeléctrica , Productos Agrícolas/metabolismo , Etanol/metabolismo , Flammulina/metabolismo , Sorghum/metabolismo , Fermentación , Hidrólisis , Cinética
6.
J Agric Food Chem ; 53(4): 1108-18, 2005 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-15713027

RESUMEN

Changes in the taste of japonica, hybrid, and indica brown and milled rice, stored for 10 months at low (5 degrees C, 65-70% relative humidity) and room temperatures were observed by physicochemical analyses and a novel method using a taste sensing system. During storage, some properties increased or decreased while others were fairly constant. The main taste components of cooked rice such as sweetness (sucrose) and umami tastes (glutamic acid and aspartic acid) were reduced during storage, whereas glucose and fructose increased. The increase of fat acidity and consequent decrease of the pH value of the cooking solution may contribute to the off-taste of cooked stored rice. A taste sensing system with 10 lipid membrane sensors was also used to classify new and old rice samples using principal component analysis. Fresh and room temperature stored japonica and indica rice could be clearly distinguished; however, it was not possible to differentiate the samples stored at low temperature.


Asunto(s)
Manipulación de Alimentos/métodos , Conservación de Alimentos , Oryza/química , Gusto , Ácido Aspártico/análisis , Fenómenos Químicos , Química Física , Ácido Glutámico/análisis , Calor , Concentración de Iones de Hidrógeno , Oryza/clasificación , Sensación , Sacarosa/análisis , Factores de Tiempo
7.
J Food Prot ; 75(10): 1823-8, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23043831

RESUMEN

The fate of radioactive cesium ((134)Cs plus (137)Cs) during the milling of contaminated Japanese wheat cultivars harvested in FY2011, and during the cooking of Japanese udon noodles made from the wheat flour, was investigated. Grain samples containing various radioactive cesium concentrations (36.6 to 772 Bq/kg [dry weight]) were milled using a laboratory-scale test mill to produce eight fractions: three break flours (1B, 2B, and 3B), three reduction flours (1M, 2M, and 3M), bran, and shorts. The concentrations of radioactive cesium were found to be highest in the bran fractions of all the samples tested, with 2.3- to 2.5-fold higher values than that of the whole grain. Shorts contained radioactive cesium levels similar to that of the whole grain. In contrast, radioactive cesium concentrations in other fractions were found to be less than half the concentration in whole grain. The average processing factor (PF) value calculated for patent flour (0.401 ± 0.048), made from the mixture of 1B, 2B, 1M, and 2M for human consumption, or for low-grade flour (0.467 ± 0.045), made from the mixture of 3B and 3M, was found to be less than 0.5; whereas the average PF value (2.07 ± 0.232) for feed bran (mixture of bran and shorts), which has been used mainly as livestock feed in Japan, was over 2.0. Boiling udon noodles (made from patent flour) resulted in a substantial reduction (>70 % of initial amount) of radioactive cesium. Moreover, radioactive cesium was reduced further (<10 % of the initial amount) in the subsequent rinsing process, and the PF value of boiled noodles was recorded as 0.194. These results demonstrated that patent flour containing radioactive cesium can be made safe for human consumption by adopting the standard limit for radioactive cesium in wheat grain and that radioactive cesium in udon noodles is substantially reduced by cooking.


Asunto(s)
Radioisótopos de Cesio/análisis , Contaminación de Alimentos/análisis , Manipulación de Alimentos/métodos , Triticum/química , Seguridad de Productos para el Consumidor , Culinaria/métodos , Terremotos , Harina/análisis , Humanos , Japón , Reactores Nucleares , Liberación de Radiactividad Peligrosa , Contaminantes Radiactivos del Suelo/análisis , Contaminantes Radiactivos del Suelo/metabolismo
8.
Int J Environ Res Public Health ; 8(6): 1957-76, 2011 06.
Artículo en Inglés | MEDLINE | ID: mdl-21776212

RESUMEN

Rice is the staple food for nearly two-thirds of the world's population. Food components and environmental load of rice depends on the rice form that is resulted by different processing conditions. Brown rice (BR), germinated brown rice (GBR) and partially-milled rice (PMR) contains more health beneficial food components compared to the well milled rice (WMR). Although the arsenic concentration in cooked rice depends on the cooking methods, parboiled rice (PBR) seems to be relatively prone to arsenic contamination compared to that of untreated rice, if contaminated water is used for parboiling and cooking. A change in consumption patterns from PBR to untreated rice (non-parboiled), and WMR to PMR or BR may conserve about 43-54 million tons of rice and reduce the risk from arsenic contamination in the arsenic prone area. This study also reveals that a change in rice consumption patterns not only supply more food components but also reduces environmental loads. A switch in production and consumption patterns would improve food security where food grains are scarce, and provide more health beneficial food components, may prevent some diseases and ease the burden on the Earth. However, motivation and awareness of the environment and health, and even a nominal incentive may require for a method switching which may help in building a sustainable society.


Asunto(s)
Culinaria/métodos , Salud Ambiental , Oryza/química , Arsénico/aislamiento & purificación , Dióxido de Carbono , Conducta Alimentaria
9.
Bioresour Technol ; 101(10): 3711-7, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20093023

RESUMEN

This paper characterizes the physico-chemical properties of the soybean oil-based polymeric surfactant, Palozengs R-004 (hereafter referred to as R-004). The surface activity of R-004 is comparable to the reported activities of biosurfactants produced by microorganisms and higher than some of the conventional synthetic surfactants. The surface tension of Milli-Q water was reduced to a minimum value of roughly 30mN/m at a concentration of about 0.07wt.%. R-004 exhibited a unique aggregation behavior: small aggregates (pre-micelles) were formed at very low concentrations. Zeta-potential measurements showed that the micelles of R-004 are negatively charged due to the presence of carboxylic groups. The ability of R-004 to form and stabilize microbubbles was evaluated and was found to be greatly affected by filtration while remaining independent of R-004 concentration over the concentration range studied (0.05-0.5wt.%). These results suggest that a very low level of surfactant can be used to produce microbubbles without affecting their properties. Our results suggest the possibility of using soybean oil-based surfactants to food, pharmaceutical, and cosmetic applications.


Asunto(s)
Aceite de Soja , Tensoactivos , Filtración , Micelas , Tamaño de la Partícula , Tensión Superficial
10.
J Colloid Interface Sci ; 332(1): 208-14, 2009 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-19144348

RESUMEN

As interest in the application of microbubbles grows, it is becoming increasingly important to understand the factors affecting their formation and properties in order to effectively generate microbubbles. This paper investigates the effect of surfactant concentration and electrolyte addition on the size distribution and stability of microbubbles. The anionic surfactant sodium dodecyl sulfate (SDS) was used as the surfactant. Minimum bubble diameter and maximum stability were achieved at surfactant concentrations above the CMC. The effect of the electrolyte addition was studied by adding sodium chloride (NaCl) at an SDS concentration below the critical micelle concentration (CMC). Addition of NaCl decreased bubble size and improved bubble preparation to a certain extent. The addition of salt at low concentrations did not affect the surface tension; however, the surface tension was reduced as salt concentration was increased and reached a constant value for NaCl concentrations above 0.25%. The presence of NaCl resulted in a significant decrease in zeta-potential, implying a reduction in the surface charge of SDS micelles. This result suggests that the presence of NaCl may improve the generation and stability of bubbles by enhancing the structures of the adsorption monolayer and interfacial film.


Asunto(s)
Electrólitos/química , Micelas , Cloruro de Sodio/química , Dodecil Sulfato de Sodio/química , Tensión Superficial , Tensoactivos/química , Modelos Químicos
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