Brown rice

About: Brown rice is a research topic. Over the lifetime, 8180 publications have been published within this topic receiving 81079 citations.

Gamma Oryzanol Content in Glutinous Purple Rice Landrace Varieties

Abstract: Our objective was to investigate whether purple glutinous rice synthesizes an agricultural nutrition distinguishable from white rice. The grains of ten purple rice landrace and two white rice varieties were examined for the amount of crude oil, semi-gamma oryzanol and gamma oryzanol (γ - oryzanol). Extrac- tions were sampled from unpolished grains. Hexane and ethyl acetate were used as the solvents in extraction of crude oil yield. The amount of γ- oryzanol was analyzed in the HPLC. The results showed that the amounts of crude oil yield extracted from the unpolished rice grain varied from 2.19 to 2.91 g/100 g brown rice. With equal amounts of crude oil fed into the HPLC, the con- tents of semi purified γ- oryzanol were equal in both rice types, of purple rice (2.08 g/100g grain, on average) and of the white rice (1.99 g/100g grain, on average). In contrast, the contents of γ- oryzanol varied among varieties. The purple rice exhibited the higher content (55.58 mg/100g brown rice, on aver- age) which was greater than the mean of the white rice check varieties (30.68 mg/100g brown rice). Genetic variation of γ- oryzanol apparently existed in the population of purple rice varieties as different contents were found. Among the purple rice, Kum Doi Saket and Kum Doi Musur yielded the greatest amount of γ- oryzanol (72.95, 70.16 mg/100 g brown rice, respectively). There was not any relationship between γ- oryzanol and crude oil content. This indicated that information on crude oil could not be applied as criteria in selection for γ- oryzanol in rice grains.

Transfer of Technetium from Soil to Paddy and Upland Rice

Abstract: Soil-plant transfer factors (concentration ratio between the plant and soil) of technetium in paddy and upland rice plants were obtained from laboratory experiments. The transfer factor is one of the most important parameters for environmental radiation dose assessment. Technetim tracer (95mTcO4-) was added to the soil prior to rice cultivation. The transfer factor of technetium for the hulled grains (brown rice) of paddy rice (< or = 0.0002) was much lower than for that of upland (0.021). The transfer factors for both types of hulled grains were much lower than in the leaves. The technetium decontamination rate from hulled grains by polishing was 34%, the percentage of the weight decrease being 12%. The concentration of technetium in the soil solution collected from the paddy rice soil (flooded conditions) decreased rapidly with time due to its adsorption on the soil. In the upland rice soil (non-flooded) solution, the decrease in the technetium concentration was fairly slow. The low transfer factors for the paddy rice plants could be explained by the immobilization of technetium in the flooded soil. The oxidation-reduction potentials (Eh) in the flooded soil decreased rapidly with time. We conclude that technetium tracer added as TcO4- to flooded soil is readily transformed to an insoluble form (e.g. TcO2) under the reducing conditions provided by flooding.

Mechanisms of carbon dioxide gas adsorp-tion by grains and its application to skin-packaging

Abstract: The data obtained with warburg's manometry have revealed that grains such as rice, wheat, corn, peanuts, soybeans, red beans, sesame seeds, and coffee beans and their flours can adsorb a significant amount of CO2 gas. The mechanism of CO2 adsorption phenomenon was examined. The results obtained are summarized as follows: 1. Solubility of CO2 gas into the moisture and lipids of the grains is assumed to have a minor effect on this adsorption phenomenon. 2. Diffusion of CO2 gas into the grain is important in this phenomenon. This adsorption phenomenon is very similar to that observed in sorp-tion of gases by charcoal and silica gel, which sorbe gases into their many pores. The CO2 sorbed by the porous tissues of the grains is considered to remain in solid solution. 3. The amount of CO2 gas adsorbed by brown rice under varying partial pressures follows the classic sorption isoterm of Freundlich. 4. Microautoradiographic experiments show that the radioactivity of 14CO2 appears to be uniformly distributed throughout the tissues of germ and cotyledon. The adsorption phenomenon has led to the development of a new techni-que for skin-packaging, the Carbon Dioxide Exchange Method (CEM). This method and two modifications are explained. The merit and useful-ness of these techniques are discussed.