Physicochemical characterization and consumer preference of rice (Oryza sativa) varieties grown in Costa Rica / Caracterización fisicoquímica y de preferencia sensorial en variedades de Arroz (Oryza sativa) de Costa Rica

Introduction: Rice is a staple food in Costa Rica representing almost 24 % of the total calorie intake in the diet. Consumers have become more quality conscious about the rice consumed, so producers need to focus on the quality of rice along with production. Objective: The aim of this study was to investigate the physicochemical profile and consumer preference of five Costa Rican rice varieties: Palmar 18, Basmatico, Chin Chin, INTA-Miravalles, and CR- 5272. Materials and methods: Proximate analysis, amylose, and mineral content were performed in the raw grain. Two different sessions were performed (n=120 each) to evaluate consumer preference measurements using the John Brown R-Index (RJB) index. The first sensory panel selected the best cooking preparation and the second, the preferred rice variety. Instrumental color measurements (L*, C*, hº, DE) were applied to the cooked rice varieties (76-96ºC for 38 min). Results: Regarding the physicochemical characterization, INTAMiravalles showed the highest protein content (8.2%), while Basmatico and Chin Chin, the lowest. Four varieties presented high amylose content (AC) and INTA-Miravalles reported an intermediate AC. The mineral content varied among varieties. INTA-Miravalles showed the highest N, followed by Palmar 18. The cooking preparation from the regulatory agency was preferred by consumers. The consumers' preference of the varieties ranked from high to low: Basmatico>Chin Chin=CR5772>Palmar 18=INTA-Miravalles. Conclusions: This study suggests that consumer preference for cooked rice was influenced by physicochemical characteristics such as protein, AC, mineral content, and aromatic attributes. Consumer acceptance is an important factor to consider when new varieties are developed. The water-to-rice ratio during cooking played an important role in cooked rice sensory quality(AU)

Introducción: el arroz es un alimento básico de consumo en Costa Rica que representa casi el 24% de la ingesta total de calorías en la dieta. Los consumidores se han vuelto más conscientes de la calidad del arroz que consumen, por lo que los productores deben enfocar esfuerzos en la calidad y producción del arroz. Objetivo: El objetivo de este estudio fue investigar el perfil fisicoquímico y la preferencia del consumidor de cinco variedades de arroz de Costa Rica: Palmar 18, Basmatico, Chin Chin, INTA-Miravalles y CR-5272. Materiales y métodos: Se realizó el análisis proximal, contenido de amilosa (CA) y de minerales en el grano crudo y color instrumental en el arroz cocido. Se realizaron dos mediciones de preferencia de los consumidores (n=120) utilizando el índice R de James Brown (RJB). En la primera se seleccionó el mejor método de preparación y en la segunda, la variedad de arroz preferido. El color instrumental (L*, C*, hº, DE) se midió a las variedades de arroz cocinado (76-96ºC por 38 min). Resultados: Miravalles mostró el mayor contenido en proteínas (8,2%), mientras que Basmatico y Chin Chin, el menor. Cuatro variedades presentaron un alto CA y el INTAMiravalles reportó un CA intermedio. El contenido mineral varió entre las variedades. INTA-Miravalles mostró el mayor contenido de nitrógeno, seguido de Palmar 18. El método de cocción del ente regulador fue el preferido por los consumidores. La preferencia de los consumidores por las variedades de mayor a menor fue: Basmatico > Chin Chin = CR5772 > Palmar 18 = INTA-Miravalles. Conclusiones: La preferencia de los consumidores por el arroz cocido se vio influenciada por características fisicoquímicas como proteína, CA, minerales y atributos aromáticos. La aceptación de los consumidores es un factor importante cuando se desarrollan nuevas variedades. La relación agua/ arroz durante la cocción desempeñó un papel importante en la calidad del arroz cocido(AU)

Chemical characterization of the antioxidant, antihyperglycemic and antihypertensive capacities of red rice (Oryza sativa L. ) whole flour / Caracteristicas físico-químicas, capacidad antioxidante, anti-hiperlucémica y antihipertensiva de la harina de arroz rojo (Oryza sativa L. )

Oryza sativa L. rice has large amounts of proteins and minerals, besides presenting several pigmented varieties. Red rice is distinguishable due to its great nutritional value compared to the regular white variety. Its red pericarp pigmentation is due to the bioactive compounds that are responsible for its health benefits. The objective of this study was to evaluate the physical-chemical characterization, antioxidant, antihyperglycemic and antihypertensive capacity of flours of three different red rice cultures (Rubi, Virgínia and Pequeno). All samples presented specific levels of carbohydrates for cereals with low fat content and excellent levels of protein and resistant starch. In addition, the samples had a high antioxidant, antihyperglycemic and antihypertensive capacity. Antihyperglycemic capacities were measured as percent inhibition for amylase (56.7-76.5%) and glycosidase (81.0-76.6%), respectively, and antihypertensive capacity as the percentage inhibition of the angiotensin converting enzyme (38.4-34.7%). In addition, Pequeno flour presented the best results for antioxidant and antihyperglycemic capacity in comparison to the two flours tested. Thus, all red rice flours can be a source of functional compounds when added to food.

El arroz integral (Oryza sativa L.) posee importantes cantidades de proteínas, vitaminas, minerales y fitoquímicos. El arroz rojo se destaca por su gran valor nutricional. La pigmentación roja del pericarpio está asociado al contenido de compuestos bioactivos, que están directamente relacionados a los beneficios de salud humana. Teniendo en cuenta lo antes expuesto se propuso evaluar las caracteristicas físico-químicas, capacidad antioxidante, anti-hiperglucémica y antihipertensiva de las harinas de tres diferentes cultivos de arroz rojo (Rubí, Virginia y Pequeño). Todas las muestras presentaron niveles específicos de carbohidratos para cereales con bajo contenido de grasa y altos contenidos de proteína y almidón resistente. Además, las muestras presentaron una alta capacidad antioxidante, anti-hiperglucémica y antihipertensiva. La capacidad anti-hiperglicémica se midió en porcentaje de inhibidores de α-amilasa (56.7-76.5%) y α-glucosidasa (81.0-76.6%), respectivamente; y capacidad antihipertensiva como el porcentaje de inhibición de la enzima convertidora de la angiotensina (38.4-34.7%). El cultivar Pequeño presentó mayor capacidad antioxidante y anti-hiperglucémica en comparación a los demás cultivares. Así, todas las harinas de arroz rojo pueden ser vehículos de compuestos funcionales en los alimentos.

Evaluación del contenido nutricional de productos lácteos en programa de alimentación venezolano / Evaluation of the nutritional content of dairy products in the Venezuelan food program

En Venezuela se distribuyen productos lácteos en polvo a través de los Comité Locales de Abastecimiento y Producción (CLAP). Con el objetivo de evaluar la composición nutricional de catorce marcas de productos lácteos provenientes de industrias mexicanas y distribuidos en Venezuela, se realizó un estudio descriptivo y transversal, con muestreo a conveniencia de 14 marcas de lácteos obtenidas en hogares beneficiados del área metropolitana de Caracas-Venezuela. Se cotejó la información presentada en el rotulado del producto y se efectuó un análisis químico de la composición nutricional. Los valores obtenidos se compararon utilizando como referencia a la norma COVENIN. En el etiquetado se encontró que sólo 2 marcas se denominan producto lácteo y el 43% de las marcas expresan el mismo contenido nutricional en el rótulo. En la analítica química se encontró inexactitud con la información presentada en el etiquetado nutricional. El análisis de componentes principales seguido de un conglomerado jerárquico permitió diferenciar 4 clúster o grupos: 2 reales y 2 ideales. La mayoría de los productos analizados son significativamente más altos en carbohidratos y sodio (p<0,05), además de bajos en proteínas y calcio (p<0,05). En conclusión, todas las muestras evaluadas incumplen la normativa correspondiente, al presentar irregularidades en la denominación del producto e informar valores que no se corresponden con el contenido nutricional resultante de los análisis químicos(AU)

In Venezuela, powdered milk products are distributed through the Local Supply and Production Committee (CLAP). The objective was to evaluate the nutritional composition of fourteen brands of dairy products from Mexican industries distributed in Venezuela, a descriptive and cross-sectional study was conducted, with convenience sampling of 14 brands of dairy products obtained in households benefiting from the Caracas Metropolitan area - Venezuela. The information presented in the product labeling was checked and a chemical analysis of the nutritional composition was performed. The values obtained were compared using the COVENIN standard as a reference. In the labeling, it was found that only 2 brands are called dairy products and 43% of the brands express the same nutritional content on the label. The chemical analysis showed inaccuracy with the information presented in the nutritional labeling. The analysis of principal components followed by a hierarchical conglomerate allowed us to differentiate 4 clusters or groups: 2 real and 2 ideal. Most of the products analyzed are significantly higher in carbohydrates and sodium (p <0.05), as well as low in protein and calcium (p <0.05). In conclusion, all the samples evaluated fail to comply with the corresponding regulations, presenting irregularities in the product name and reporting values that do not correspond to the nutritional content resulting from chemical analyzes(AU)

Determinação de pH em diferentes etapas da preparação de materia prima (arroz) para sushis em restaurantes de comida japonesa de Porto Alegre/RS / Determination of pH in different moments of preparation of sushis raw material (rice) in japanese food restaurants of Porto Alegre/RS

A gastronomia japonesa no Brasil tem conquistado cada vez mais adeptos, utilizando pescados crus ou in natura em seus pratos mais populares. A preparação do arroz utilizado na elaboração de sushi é complexa e exige cuidados quanto ao pH, visando manter o alimento seguro. O objetivo deste trabalho foi determinar o pH do arroz utilizado na preparação de sushi em cinco restaurantes japoneses na cidade de Porto Alegre/RS, avaliando o cumprimento da Portaria municipal 1109/2016. A matéria prima (arroz) utilizada para a preparação de sushi nos restaurantes estudados foi submetida à aferição de pH em dois momentos diferentes, logo após a cocção e após o tempero. Os restaurantes analisados apresentaram resultado favorável no que diz respeito ao pH, sendo os valores encontrados iguais ou menores que 4,5 conforme estipulado pela legislação municipal vigente.

Concentrado proteico de arroz na alimentação do jundiá (Rhamdia quelen) / Rice protein concentrate in the feeding of silver catfish (Rhamdia quelen)

O objetivo do presente trabalho foi avaliar a inclusão do concentrado proteico da destilação de etanol obtido de arroz (CPA) na alimentação do jundiá. Trezentos e setenta e cinco peixes foram distribuídos em sistema de recirculação de água com 15 caixas (125L). Foram testadas três dietas (37% PB e 3200kcal/kg de energia digestível), sendo uma controle e duas testando a substituição da proteína da farinha de peixe em 25% (CPA-25%) ou 50% (CPA-50%) pelo CPA. Aos 30 dias, foram avaliadas as variáveis de desempenho, composição corporal e índices somáticos. Os animais submetidos ao tratamento CPA-25% apresentaram resposta de crescimento equivalente aos que receberam o tratamento controle, mas superior aos peixes submetidos ao CPA-50%. Não foram observadas diferenças significativas entre os tratamentos para os índices somáticos avaliados. Os animais submetidos às dietas contendo CPA apresentaram maior teor de gordura corporal. Já a deposição de gordura corporal foi superior para os peixes alimentados com CPA-25%, e a deposição de proteína corporal menor para os alimentados com CPA-50%. Os resultados indicam que o CPA pode substituir em até 25% a proteína da farinha de peixe, sem comprometer o crescimento dos jundiás, tendo esse nível de substituição proporcionado, inclusive, uma redução de 8% no custo da dieta.(AU)

The objective of this work was to evaluate the inclusion of protein concentrate from the distillation of ethanol from rice (CPA) in jundia feed. A total of 375 fish were distributed in water recirculation system with 15 boxes (125L). Three diets (37% PB and 3200kcal / kg digestible energy), one control and two were to test for the replacement of fishmeal protein by 25 (CPA-25%) and 50% (CPA-50%) by CPA. At 30 days, the variables of performance, body composition and somatic indexes were evaluated. The animals submitted to the CPA-25% treatment presented a growth response equivalent to those that received the Control treatment, but superior to the fish submitted to the CPA-50%. There were no significant differences between treatments for the somatic indices evaluated. Animals submitted to diets containing CPA had higher body fat content. Body fat deposition was higher for fish fed with CPA-25% and lower body protein deposition for those fed with CPA-50%. The results indicate that CPA can substitute up to 25% fish meal protein, without compromising the growth of jundias, and this level of substitution provided an 8% reduction in diet cost.(AU)

A comparative proteomic study of white and black glutinous rice leaves

Background Black glutinous rice contains remarkable levels of anthocyanins, which possess anti-oxidative properties and thus have health benefits. The accumulation of anthocyanins in grains of thirty black glutinous rice varieties was measured, and the results revealed that the accumulated anthocyanin content ranged from 0.262 to 2.539 mg/g. Black glutinous rice Br no. 19 was selected, and its leaf protein expression profile was compared with that of white glutinous rice RD 6 using 2D-PAGE, and the protein spots were then directly analyzed after proteolysis by LC-MS/MS. Results The proteins from the leaves of the two rice varieties were separated using 2D-PAGE and silver stained, and the spots were analyzed using Image Master 2D Platinum version 5 software. The results showed that the protein profiles of these two rice cultivars were different, with at least six protein spots that were detected only in Br no. 19. In addition, seven protein spots accumulated at higher levels in Br no. 19 than in RD 6. Conclusion The protein spot S1 (AP005098.4) is homologous to the Rc protein. Our results suggest that some of the proteins enriched in Br no. 19 may be involved in anthocyanin synthesis in the black glutinous rice.

Evaluación de un ingrediente funcional para el control glicémico en humanos / Evaluation of a functional ingredient for glycemic control in human

The prevalence of non-transmissible chronic diseases such as obesity, dyslipidemia and type 2 diabetes, among others, have increased worldwide. One way to prevent and/or control them is through bioactive food compounds that can be incorporated as functional ingredients (IF). The IF isa compound IF: apple pomace, opuntia palette, tomato pomace and rice bran. Objective: Assess the functional ingredient (IF) for glycemic control in humans. Subjects and Methods: 48 Subjects, both sexes, aged between 40 and 60. Divided into three groups: non-obese (NO), obese (OB) and diabetic (DM) with 16 subjects per group. Subjects consumed 600 g daily of nonfat yogurt with artificial sweetener. 50 percent of the subjects in each group received yogurt with IF and 50 percent without IF for 44 days. Metabolic control of capillary blood glucose was performed weekly, of nutrition every week, as well as basal metabolic control, 22 and 44 with: fasting blood glucose, lipid profile, tolerance test to glucose with 2 point sampling and calculation of HOMA-IR. All analyses were performed at the Institute of Nutrition and Food Technology (INTA), University of Chile. The statistical analysis included measures of central tendency and dispersion. They compared the effect of the intervention vs control using the Mann-Whitney U test for independent samples and the Chi2 test for categorical variables. Results:15 subjects from the DM group, 16 from OB and 10 from NO completed the experiment. Significant differences were found between the intervention group and the placebo in the obese group, in the weight variation of the basal-22 days, 22-44 and basal-44 days with p = 0.007, p = 0.001 and p = 0.001respectively, and significant differences in the NO group between the placebo and intervention groups in the variation basal-22 days for HOMA-IR (p = 0.010) and 44 -22 days for LDL (p = 0.045). Conclusion: In this study no significant differences were found for subjects stratified into...

Simultaneous determination of 17 pesticide residues in rice by GC/MS using a direct sample introduction procedure and spiked calibration curves

A reliable, rapid and accurate method based on spiked calibration curves and direct sample introduction was developed for determination of 17 pesticide residues in rice by gas chromatography-mass spectrometry single quadrupole selected ion monitoring GC/MS-SQ-SIM. Sample preparation is based on extraction with acetonitrile without clean up. The use of spiked calibration curves for constructing the calibration curve substantially reduced adverse matrix-related effects. The average recovery of pesticides at 6 concentration levels was in range of 97.5-102.1%. The method was proved to be repeatable with RSDr in range of 0.7%-19.8%for all of the concentration levels. The limits of detection and limit of quantifications for all the pesticides were < 10 ng/g and < 25 ng/g, respectively. The developed method was applied for simultaneous determination of the selected pesticides in 23 rice samples collected from Tehran retail market in March 2009. Although many studies have been conducted regarding the determination of pesticides by using GC-MS, this is the first attempt in Iran using GC-MS-SIM technique that successfully can determine 17 pesticides with difference in physicochemical properties in rice

Black rice anthocyanidins prevent retinal photochemical damage via involvement of the AP-1/NF-kappaB/Caspase-1 pathway in Sprague-Dawley Rats

The effects of black rice anthocyanidins (BRACs) on retinal damage induced by photochemical stress are not well known. In the present study, Sprague-Dawley rats were fed AIN-93M for 1 week, after which 80 rats were randomly divided into two groups and treated with (n = 40) or without BRACs (n = 40) for 15 days, respectively. After treatment, both groups were exposed to fluorescent light (3,000 +/- 200 lux; 25degrees C), and the protective effect of dietary BRACs were evaluated afterwards. Our results showed that dietary BRACs effectively prevented retinal photochemical damage and inhibited the retinal cells apoptosis induced by fluorescent light (p < 0.05). Moreover, dietary BRACs inhibited expression of AP-1 (c-fos/c-jun subunits), up-regulated NF-kappaB (p65) expression and phosphorylation of IkappaB-alpha, and decreased Caspase-1 expression (p < 0.05). These results suggest that BRACs improve retinal damage produced by photochemical stress in rats via AP-1/NF-kappaB/Caspase-1 apoptotic mechanisms.

Aflatoxin contamination in stored rice variety PAU 201 collected from Punjab, India.

Background & objectives: The present study was carried out on stored rice variety PAU 201 in Punjab that was not permitted for milling and public distribution due to the presence of damaged grains at levels exceeding the regulatory limits of 4.75 per cent. The aim of the study was to determine fungal and aflatoxin contamination in the rice samples to assess hazard from the presence of damaged grains. Presence of iron in discoloured rice grains was also assessed. Methods: Stored samples of paddy of PAU 201 rice variety were collected from six districts of Punjab, milled and analysed for presence of fungal and aflatoxin contamination. Scanning electron microscopy (SEM), energy dispersive X-ray (EDX) analysis and Prussian blue staining was used to determine fungal spores and presence of iron, respectively. Results: Aflatoxin analysis of rice samples indicated that none exceeded the Food Safety and Standards (Contaminants, Toxins and Residues) Regulations, 2011 tolerance limit of 30 μg/kg and majority of the samples had levels <15 μg/kg. The proportion of damaged grains exceeding the limit of 5 per cent was observed in 85.7 per cent of the samples. SEM and Prussian blue staining and EDX analysis of black tipped and pin point damaged rice grains did not show presence of fungal structures and presence of iron. Interpretation & conclusions: The results of the study indicated that the stored rice samples did not pose any health concern with respect to aflatoxin contamination as per the criteria laid down by the Food Safety and Standards Authority of India.

Carbohydrate content and antioxidative potential of the seed of three edible indica rice (Oryza sativa L.) cultivars.

Rice (Oryza sativa L.) grains or seeds are known to lose much of their nutrient and antioxidant contents, following polishing. The current study was undertaken to evaluate and compare the carbohydrate content and antioxidant parameters in the unpolished and polished seeds of three edible indica rice cultivars, namely Swarna (SW), the most popular indica rice cultivar in India and aromatic or scented cultivars Gobindobhog (GB) and Pusa Basmati (PB). While both the sucrose and starch content was the maximum in PB seeds (both unpolished and polished), the amylose content was the highest in SW polished seeds. SW polished seeds were superior as compared to GB and PB cultivars in terms of total antioxidant capacity, DPPH radical scavenging and Fe(II) chelation potential, as well as the highest lipoxygenase (LOX) inhibition or H2O2 scavenging potential, probably due to the maximum accumulation of total phenolics and flavonoids, the two important antioxidants. The reducing power ability was, however, identical in both SW and GB polished seeds. The PB polished seeds were more potent in superoxide and hydroxyl scavenging, whereas GB in nitric oxide (NO) scavenging. The common observation noted after polishing of seeds was the reduction in the level of carbohydrates and antioxidant potential, though the extent of reduction varied in the three cultivars. The only exception was GB, where there was no alteration in NO scavenging potential even after polishing. Our study showed the better performance of SW polished seeds with respect to higher amylose content and majority of the tested parameters governing antioxidant capacity and radical scavenging potential, thus highlighting the greater dietary significance of SW over the other two cultivars.

Nutritional composition of rice bran submitted to different stabilization procedures

In order to inactivate enzymatic deterioration, whole rice bran samples were subjected to two stabilization methods. Changes in nutritional value in terms of, concerning chemical composition, minerals and fatty acid content, were evaluated to supplement existing data and promote the utilization of rice bran in the human diet. The following homemade heat treatments were applied: roasting on a conventional stove or heating in a microwave oven. Based on the results, the different heating methods affected sample composition, since the levels of some nutrients of treated samples showed significant changes (p<0.05) compared to corresponding raw samples. The rice bran treated on a conventional stove produced products with lower moisture (5.14±0.10 g/100 g) and nutrients such as sodium 11.8%; palmitic acid 9.9% and stearic acid 8.1%. The microwave oven procedure resulted in better nutrient preservation, with slightly higher moisture content (6.28±0.10 g/100 g), and appears to be a practical and rapid tool for home heat stabilization of rice bran.

A fim de inativar a deterioração enzimática, as amostras de farelo de arroz foram submetidas a dois métodos de estabilização. As mudanças do valor nutricional, no que se refere a composição química, os minerais e o conteúdo de ácidos graxos, foram avaliadas para adicionar mais informações aos dados existentes e promover a utilização de farelo de arroz na dieta humana. Os seguintes tratamentos caseiros por calor foram aplicados: torra em forno convencional ou de aquecimento em forno de micro-ondas. Com base nos resultados, os diferentes métodos de aquecimento afetaram a composição das amostras, já que os níveis de alguns nutrientes mostraram alterações significativas (p <0,05), comparado com as amostras cruas correspondentes. O farelo de arroz tratado em fogão convencional forneceu produtos com menos umidade (5,14 ± 0,10 g/100 g) e nutrientes, tais como: de sódio 11,8%; ácido palmítico 9,9% e ácido esteárico 8,1%. O procedimento de forno de micro-ondas resultou em melhor preservação dos nutrientes, com teor de umidade um pouco maior (6,28 ± 0,10 g/100 g), o que parece ser uma ferramenta prática e rápida no tratamento térmico caseiro para o farelo de arroz.

Perspectivas del uso de bacterias rizosféricas en el control de Pyricularia grisea (Cooke Sacc) en el cultivo del arroz (Oryza sativa L) / Prospect of the use of bacteria in the control Pyricularia grisea (Cooke Sacc) on rice (Oriza sativa L)

El arroz es fuente de alimento para una gran parte de la población mundial, con alto promedio de consumo anual. En este cultivo las enfermedades de origen microbiano constituyen uno de los factores que inciden en la obtención de bajos rendimientos y calidad de los granos. La piriculariosis o añublo del arroz, causada por Pyricularia grisea, es la enfermedad más importante en este cultivo en América Latina, ya que puede provocar hasta el 100% de reducción de los rendimientos. Como parte de la estrategia de agricultura sostenible, se trata de controlar estos patógenos y lograr altos rendimientos del cultivo mediante una combinación adecuada de fertilizantes químicos y productos biológicos. En este sentido, la aplicación de inoculantes bacterianos constituidos por bacterias promotoras del crecimiento vegetal (Plant Growth- Promoting Bacteria, PGPB, por sus siglas en inglés) ha constituido una alternativa ecológica que favorece la conservación del medioambiente y el ecosistema. Este trabajo tiene como objetivo abordar el estado actual y las perspectivas de uso de bacterias rizosféricas en el control de Pyricularia grisea en el cultivo del arroz, tratando algunos temas relevantes, como son las principales enfermedades que afectan al cultivo, los géneros de PGPB más utilizados para el control de las mismas y sus principales mecanismos de acción.

Rice is an important food supply for a large part of the world population and its consumption rates are very high. Microbial diseases are one of the main causes that provoke low yields and low-quality spotted grains. Although fungi, bacteria and viruses are mostly the responsible for these losses, fungal diseases strike more frequently. Among fungi, Pyricularia grisea, the blast fungus is responsible for up to 100% of reduction in yields, being the blast the most important rice disease in Latin America. To control this pathogen, a strategy of sustainable agriculture might be developed, combining accurately chemical and biological products. PGPB based bioproducts have been considered as an eco-friendly alternative, which favours environment preservation. This work was aimed to approach the current status and outlook of the use of rhizobacteria in the biocontrol of Pyricularia grisea on rice. Main diseases attacking rice, most beneficial PGPB and its mechanisms of action will be discussed too in this review.

High-level expression of modified gene encoding human adiponectin in transgenic rice

Adiponectin is a polypeptide specifically secreted from human adipocytes, and its deficiency is closely linked to increased obesity and type II diabetes. There is an urgent demand for large-scale production of human adiponectin for pharmaceutical applications. Here, we report that we have successfully obtained a high-level of expression of modified genes encoding human adiponectin in transgenic rice. The 735 bp cDNA of the native human sequence was adopted to rice codon usage, fused to the translation initiation sequence in the N terminus and to the KDEL signal sequence in the C terminus. An amplification promoting sequence acting as an enhancer of transcription was also introduced to enhance gene expression. The presence of the transgene and mRNA transcripts was confirmed by PCR, Southern blot and RT-PCR. Western blot analysis revealed that a protein of approximately 30 kDa was produced in rice leaves. ELISA analysis was used to determine the amount of recombinant adiponectin in transformants with the modified gene in up to 0.32% of total soluble leaf protein. Our results establish the feasibility of high-level expression of recombinant human adiponectin in transgenic rice.

Characterization of seeds of selected wild species of rice (Oryza) stored under high temperature and humidity conditions.

Wild progenitors of rice (Oryza) are an invaluable resource for restoring genetic diversity and incorporating useful traits back into cultivars. Studies were conducted to characterize the biochemical changes, including SDS-PAGE banding pattern of storage proteins in seeds of six wild species (Oryza alta, O. grandiglumis, O. meridionalis, O. nivara, O. officinalis and O. rhizomatis) of rice stored under high temperature (45oC) and humidity (~100%) for 15 days, which facilitated accelerated deterioration. Under the treated conditions, seeds of different wild rice species showed decrease in per cent germination and concentrations of protein and starch, but increase in conductivity of leachate and content of sugar. The SDS-PAGE analysis of seed proteins showed that not only the total number of bands, but also their intensity in terms of thickness differed for each species under storage. The total number of bands ranged from 11 to 22, but none of the species showed all the bands. Similarity index for protein bands between the control and treated seeds was observed to be least in O. rhizomatis and O. alta, while the indices were 0.7 and 0.625 for O. officinalis and O. nivara, respectively. This study clearly showed that seed deterioration led to distinctive biochemical changes, including the presence or absence as well as altered levels of intensity of proteins. Hence, SDS-PAGE protein banding pattern can be used effectively to characterize deterioration of seeds of different wild species of rice.

Efeitos da parboilização do arroz (Oryza sativa L. ) integral sobre os compostos bioativos e a disponibilidade do amido / Effects of the parboiling process in brown rice (Oryza sativa L. ) on its both bioactive components and starch availability

O arroz (Oryza sativa L.) é consumido principalmente na forma polida, porém uma alternativa nutricionalmente melhor seria o arroz integral, que contém ao redor de 10% de farelo, rico em micronutrientes e compostos bioativos. Dentre esses destacam-se a vitamina E e γ-orizanol, aos quais se atribuem diversos efeitos benéficos à saúde. A literatura descreve vários estudos relacionados à presença desses compostos no arroz integral, porém pouco se sabe a respeito da sua estabilidade com o armazenamento, a parboilização e a cocção caseira. Pelo fato do arroz integral apresentar curta vida de prateleira, uma alternativa para aumentar o prazo para o consumo é o emprego da parboilização. A parboilização, que consiste em um processo hidrotérmico, provoca alterações estruturais no amido do grão e a literatura é controversa no que diz respeito à diminuição da digestibilidade do amido e consequentemente à redução do índice glicêmico (IG). Este trabalho teve como objetivos: avaliar os efeitos da parboilização sobre a disponibilidade do amido por meio da cinética de hidrólise do amido estimando o índice glicêmico (IG) em cultivares de arroz integral com diferentes teores de amilose; analisar o efeito da parboilização, do armazenamento por seis meses e da cocção caseira do arroz integral sobre a estabilidade dos compostos bioativos, e correlacionar os compostos bioativos com a atividade antioxidante do arroz, antes e após o processamento. Foram analisadas 36 amostras pertencentes a diferentes cultivares selecionadas de arroz integral e parboilizado integral das safras de 2007 e 2008 e outras três amostras de arroz integral e parboilizado integral, adquiridas no comércio local da cidade de São Paulo. A partir do índice de hidrólise (IH) in vitro, foi estimado o IG. A vitamina E e o γ-orizanol foram extraídos com metanol, separados por CLAE-fase reversa e quantificados por curvas padrão correspondentes. A atividade antioxidante foi avaliada pelos métodos de DPPH• e ORAC...

Rice (Oryza sativa L.) is consumed mostly in the milled form. However, due to its content of bran, vitamin E and γ-oryzanol, the intake of brown rice has been recommended. Although previous studies ascribed some important health benefits related to these brown rice's compounds, information regarding the effect of cooking, storage and parboiling on these substances remains to be elucidated. Rice parboiling is a hydrothermal process consisting of soaking, heating and drying that provide technological and nutritional benefits to the consumer. Until now, if parboiling process decreases the starch digestibility and consequently reduces the glycemic index (GI) is unclear. The objectives of the present study were: to evaluate the effect of the parboiling process on starch digestibility through a GI estimation by the kinetics of starch hydrolysis in rice cultivars with different levels of amylose; to analyze the effect of traditional parboiling, cooking and storage for six months on the stability of bioactive components as well as to correlate the content of bioactive components of rice with its antioxidant activity before and after parboiling. Thirty-six samples of brown rice and parboiled brown rice harvested in 2007 and 2008 were analyzed. In addition, three commercial cultivars of both brown and parboiled brown samples from local market that were obtained in São Paulo were also studied. The glycemic index (IG) was estimated from the hydrolysis index (IH). Vitamin E homologues and γ-oryzanol were extracted simultaneously with methanol and analyzed by HPLC-RP/UV and fluorescence detection in a single run. Peak areas were converted to the corresponding by the standards of α- and γ-tocopherol, α- and γ-tocotrienol and γ-oryzanol. The antioxidant capacity was evaluated by both, DPPH• and ORAC methods. The results indicated that starch digestibility from all rice samples was little affected by parboiling under the conditions employed in the present study. Samples with...

Composición de las soluciones caseras usadas en ninos con diarrea sin deshidratación: Mérida-Venezuela: [revisión] / Composition of home made solutions used in children with diarrhea without dehydration: [review]

La diarrea es una causa principal de morbi-mortalidad en niños y el uso de la terapia de rehidratación oral (uso de suero oral más líquidos caseros) puede prevenir la deshidratación. Identificar las soluciones caseras utilizadas en los niños con diarrea sin deshidratación, analizar su composición bioquímica y proponer las más adecuadas. Se entrevistaron 167 madres, en consultas pediátricas, seleccionadas al azar, durante los años 2004-2006, en Mérida-Venezuela; es un estudio epidemiológico, analítico, prospectivo y concurrente. Se identificaron cinco grupos de soluciones caseras: agua de arroz, sopa de plátano, sopa de cambur (banana), infusiones de hierbas y jugos de frutas. El análisis bioquímico se realizó mediante un pH metro, espectroscopia de absorción atómica (Na y K), argentometría (Cl), osmómetro (osmolaridad), glucosa peroxidasa (glucosa), hidrovolumetría por neutralización (bicarbonato) y bandas de absorción (citrato), procesadas en la Facultad de Ciencias de la Universidad de Los Andes. Todas las soluciones estudiadas tienen un pH ácido, con excepción del suero casero con bicarbonato. las concentraciones de electrolitos fueron mínimas en el agua de arroz, las infusiones de hierbas y los jugos de frutas, mientras que fueron más elevadas en las sopas de plátano y banana. (Na y Cl más elevado). Las osmolaridad fue baja en todas las soluciones y alta en los jugos de frutas. Ninguna de las soluciones reúne las concentraciones planteadas por la OMS, aunque en el niño con diarrea sin deshidratación la sopas de plátano y banana pueden ser utilizadas debido a la buena aceptación y al bajo costo. No se recomiendan los jugos de fruta por su alta osmolaridad.

Diarrhoea continues to be one the main causes of morbidity-mortality in latin american countries due to dehydration. this is why the most important strategy to avoid deaths due to dehydration is oral rehydration therapy (oral rehydration solution plus homemade solutions) which may vary according to each region of the country. To identify the most frequently used homemade solutions for preventing dehydration in children with acute diarrhoea within the community in Mérida, Venezuela; to analyze the biochemical composition of these solutions; to propose the use of the most adequate ones. By means o an epidemiological, analytical, prospective and concurrent study 167 inquiries were performed to mothers who sought medical help in the main assistance centers of the city. these mothers were selected randomly during 2004-2006. five groups of homemade solutions were identified: rice water (golden rice in esther grain or flour), plantain soup with or without chicken, banana soup, herbal infusions and fruit juices. Biochemical analysis was performed by means of: ohmmeters (pH), spectroscopy of atomic absorption (Na and K), argentometry (Cl), osmometer (osmolarity), glucose peroxidase (glucose), hidrovolumetry by neutralization (bicarbonate) and absorption bands (citrate) processed at the Science Faculty of the Universidad de Los Andes. All the homemade liquids have an acidic pH, except solutions with added bicarbonate. electrolytes concentrations were minimum except for the plantain and banana soups, which have a higher sodium and chloride concentration. The osmolarity of most solutions was low, with exception of fruit juices (orange and guava). Conclusions: none of the homemade solutions meet the requirements established by the World Health Organization as an ideal rehydration solution. However, plantain and banana soup may be used in children with diarrhea without dehydration due to their high availability.

Antioxidant activity of commonly consumed cereals, millets, pulses and legumes in India.

Plant foods are important due to their antioxidant activity (AOA) attributed to the phenolics which are known to protect organisms against harmful effects of oxygen radicals. However, information on antioxidant activity of Indian plant foods is scanty. Therefore, the present study evaluated the AOA of cereals, millets, pulses and legumes, commonly consumed in India and assessed the relationship with their total phenolic content (TPC). AOA was assessed by DPPH (2,2-Diphenyl-1-picryl hydrazyl) radical scavenging assay, ferric reducing antioxidant power (FRAP) assay and reducing power. DPPH scavenging activity ranged from 0.24 and 1.73 mg/g, whereas FRAP ranged from 16.21 to 471.71 micromoles/g. Finger millet (Eleusine cora cana) and Rajmah (Phaseolus vulgaris) had the highest FRAP 471.71, 372.76 and DPPH scavenging activity 1.73, 1.07. Similar trends were observed with reducing power. Among cereals and legumes, Finger millet (Ragi) and black gram dhal (Phaseolus mungo Roxb) had the highest TPC, the values being 373 and 418 mg/100 g respectively, while rice (Oryza sativa) and green gram dhal (Phaseolus aureus Roxb) showed the least (47.6 and 62.4 mg/100 g). In the present study, FRAP (r = 0.91) and reducing power (r = 0.90) showed significant correlation with TPC in cereals and millets, but not in pulses and legumes. The results suggest that TPC contributes significantly to the AOA of Indian cereals and millets.

Arroz parboilizado efeito na glicemia de ratos Wistar

O amido é uma importante fonte energética podendo representar mais de 60% da ingestão calórica na dieta humana. A fração do amido, que é resistente à digestão enzimática, é denominada de amido resistente. Na parboilização de arroz ocorre a retrogradação do amido, com a formação do amido resistente tipo 3 (retrogradado), que apresenta efeitos benéficos à saúde, por atuar como prébiótico. Neste estudo, três amostras de arroz com alta, média e baixa amilose foram selecionadas, com o objetivo de avaliar o efeito de arroz convencional e parboilizado na glicemia de ratos Wistar. As amostras com alta e média amilose foram encharcadas durante 6h a 65°C e a amostra com baixa amilose durante 7h a 70°C, posteriormente foram autoclavadas em pressão 0,7 kgf.cm-2 durante 10 minutos. Utilizouse 6 ratos Wistar, machos, adultos por tratamento. Foram elaboradas 7 dietas experimentais, formuladas de acordo com AIN-93M, dieta controle e, dietas com substituição da fonte de carboidratos por arroz convencional e parboilizado. Determinou-se amido resistente nas dietas e a glicemia foi monitorada por leitura de glicofita, com sangue da parte distal da cauda do rato. Para a curva glicêmica as medidas de glicemia foram feitas em jejum, e ao longo de 90 minutos. Os resultados indicam que não foram encontradas diferenças significativas entre as dietas formuladas com arroz de alta, média e baixa amilose, parboilizado ou convencional na glicemia de jejum e pós-prandial de ratos Wistar.

The effect of parboiled rice on glycemia in Wistar rats. Starch is an important energy source and can represent more than 60% of the calories of the human diet. The starch fraction resistant to enzymatic digestion is called resistant starch. When rice is parboiled, the starch retrogrades with the formation of type 3- resistant starch (retrograded), which presents beneficial effects on the health, since it acts as a prebiotic. In the present study three types of rice were selected, with high, medium and low amylose contents, with the objective of evaluating the effects of conventional and parboiled rice on glycemia in Wistar rats. The samples with high and medium amylose contents were soaked for 6 h at 65ºC, and the low amylose sample for 7 h at 70ºC. The samples were subsequently autoclaved for 10 minutes at 0.7kgf.cm-2. Six male Wistar rats were used for each treatment. Seven experimental diets were elaborated, formulated according to AIN-93M, the control diet and diets substituting the carbohydrate source with conventional or parboiled rice. Resistant starch was determined in the diets and glycemia monitored using glucose paper strips, the sample being blood obtained from the distal part of the rat’s tail. For the glycemic curve, glycemia was measured in the fasting state and during 90 minutes post-prandial. The results indicated there were no significant differences between the diets formulated with high, medium and low amylose, parboiled or conventionally prepared, with respect to fasting or post-prandial glycemia in Wistar rats.