VITAMINA D EN LA PREVENCIÓN Y EVOLUCIÓN DE LA DIABETES MELLITUS / VITAMIN D IN THE PREVENTION AND EVOLUTION OF DIABETES MELLITUS

Introducción: El déficit de vitamina D y la diabetes son dos situaciones prevalentes en todas las edades, regiones geográficas y niveles socioeconómicos. La presencia de receptores para 1,25(OH)2D y la existencia de la enzima 1-α-hidroxilasa en la célula beta ­que permite la síntesis del metabolito activo­ sugieren que la vitamina D juega un papel importante en dichas células y que su deficiencia podría ser un factor capaz de acelerar el inicio y la evolución de la enfermedad. Objetivos: Se realizó una revisión del tema vitamina D y Diabetes. A su vez, se analizó el rol de la vitamina D en la insulinorresistencia y en la DM2, así como en la autoinmunidad y la DM1. También se indagó en el estado actual sobre los efectos de la suplementación con vitamina D en la prevención, el control glucémico y la evolución de las complicaciones asociadas a esta enfermedad. Materiales y Métodos: Se realizó una búsqueda bibliográfica utilizando los buscadores PubMed, MEDLINE, Cochrane, Research Gate. Los criterios de búsqueda fueron "vitamin D", "vitamin D and diabetes", "vitamin D and supplementation". Conclusiones: Existe suficiente evidencia acerca de que los niveles séricos de 25(OH)D deberían alcanzar valores entre 30 y 50 ng/ml para influir en las funciones metabólicas. Se enfatiza en la importancia de incluir el dosaje de 25(OH)D en el control clínico de rutina. Teniendo en cuenta la escasa distribución de la vitamina D en los alimentos naturales, el bajo consumo de los alimentos fuente en la población argentina y las recomendaciones actuales de limitar la exposición al sol por el cáncer de piel, emerge como necesario contar con alimentos fortificados de consumo masivo, además de la leche

Introduction: Vitamin D deficiency and diabetes are two prevalent situations in all ages, geographic regions and socioeconomic levels. The presence of receptors for 1,25(OH)2D and the existence of the enzyme 1-α-hydroxylase in the beta cell ­which allows the synthesis of the active metabolite­ suggest that vitamin D plays an important role in these cells and that vitamin deficiency could be a factor that can accelerate the onset and progression of the disease. Objectives: The subject vitamin D and Diabetes was review. The role of vitamin D in insulin resistance and DM2, as well as autoimmunity and DM1, were analyze. We also evaluated the effects of vitamin D supplementation on prevention, glycemic control and evolution of associated complications. Materials and methods: A bibliographic search was carried out using the search engines PubMed, MEDLINE, Cochrane, Research Gate. The search criteria were "vitamin D", "vitamin D and diabetes", "vitamin D and supplementation". Conclusions: There is sufficient evidence that blood levels of 25(OH)D should reach values between 30 and 50 ng/ml to influence metabolic functions. The importance of including 25(OH)D dosage in routine clinical control is emphasized. Taking into account the scarce distribution of vitamin D in natural foods, the low consumption of source foods in the Argentine population and the current recommendations to limit sun exposure due to skin cancer, it emerges as necessary to have fortified foods for mass consumption, in addition to milk

Correction: Effects of extruded whole-grain sorghum (Sorghum bicolor (L.) Moench) based diets on calcium absorption and bone health of growing Wistar rats.

Correction for 'Effects of extruded whole-grain sorghum (Sorghum bicolor (L.) Moench) based diets on calcium absorption and bone health of growing Wistar rats' by María Gimena Galán et al., Food Funct., 2020, 11, 508-513, DOI: 10.1039/C9FO01817D.

Vitamina D y Diabetes Mellitus. Parte 1 / Vitamin D and Diabetes Mellitus. Part 1

Introducción: la diabetes mellitus (DM) se ha convertido en un importante problema global de salud pública. Por su parte, el déficit de vitamina D (VD) tiene características de pandemia y sus consecuencias van más allá de su conocido efecto sobre el metabolismo óseo. El descubrimiento de receptores de la vitamina en diversos tejidos despertó un creciente interés en funciones no esqueléticas, varias de las cuales se relacionan con la prevención y evolución de la DM. La 25(OH)D es la principal forma circulante y constituye el marcador más adecuado y el más utilizado para evaluar el estado nutricional de VD, ya que refleja tanto la producción endógena cuanto la ingesta de la vitamina. Objetivos: como Grupo de Trabajo nos propusimos hacer una revisión del tema VD y DM. En esta primera parte analizamos la VD: los aspectos metabólicos, el aporte alimentario y las controversias sobre la definición de los niveles séricos adecuados. Materiales y métodos: se realizó una búsqueda bibliográfica utilizando los buscadores PubMed, MEDLINE, Cochrane, Research Gate. Los criterios de búsqueda fueron "vitamin D", "vitamin D and diabetes", "vitamin D functions, metabolism, sources" "vitamin D toxicity". Se seleccionaron artículos completos relacionados con el tema. El contenido de vitamina D de los alimentos se obtuvo de las bases de datos de composición de alimentos Souci Fachmann Kraut y USDA. Conclusiones: teniendo en cuenta la escasa distribución de la VD en los alimentos naturales, el bajo consumo de los alimentos fuente en la población argentina y las recomendaciones actuales de limitar la exposición al sol por el cáncer de piel, emerge como necesario contar con alimentos fortificados de consumo masivo, además de la leche. Los suplementos nutricionales ofrecen una opción segura para complementar la dieta siempre que se supervisen los niveles séricos. No hay consenso sobre los niveles de referencia para considerar a un individuo deficiente, aunque la mayor parte de los autores coincide en la necesidad de mantener niveles séricos por encima de 30 ng/ml

Introduction: diabetes mellitus (DM) has become a major global public health problem. Vitamin D (VD) deficiency, on the other hand, has pandemic characteristics and its consequences go beyond its known effect on bone metabolism. The discovery of vitamin receptors in various tissues has led to increased interest in non-skeletal functions, many of which are related to the prevention and progression of DM. 25(OH) D is the main circulating form and is the most appropriate and most widely used marker for assessing the nutritional status of VD, since it reflects both endogenous production and intake of the vitamin. Objectives: as a Working Group we proposed to make a review of the topic VD and Diabetes. In this first part we analyzed the VD: metabolic aspects, food intake and controversies about the definition of adequate serum levels. Materials and methods: a bibliographic search was carried out using the PubMed, MEDLINE, Cochrane, Research Gate search engines. The search criteria were "vitamin D", "vitamin D and diabetes", "vitamin D functions, metabolism, sources" "vitamin D toxicity". Complete articles related to the topic were selected. The vitamin D content of foods was obtained from the Souci Fachmann Kraut and USDA food composition data bases. Conclusions: considering the scarce distribution of VD in natural foods, the low consumption of source foods in the Argentine population and the current recommendations to limit sun exposure due to skin cancer, it is necessary to have fortified foods for massive consumption, in addition to milk. Nutritional supplements offer a safe option to supplement the diet as long as serum levels are monitored. There is no consensus on reference levels for considering an individual deficient, although most authors agree on the need to maintain serum levels above 30 ng/m

Refined sorghum flours precooked by extrusion enhance the integrity of the colonic mucosa barrier and promote a hepatic antioxidant environment in growing Wistar rats.

The effects of precooked-refined sorghum flour consumption on antioxidant status, lipid profile, and colonic and bone health were evaluated. Twenty-four male Wistar rats were fed with control diet (C), or red or white precooked-refined sorghum based diets (SD) for 60 days. The intake of SD was lower than that of C, but the efficiency of all diets was similar. Rats fed with SD showed lower feces excretion, cecal pH and enzyme activities (ß-glucosidase, ß-glucuronidase and mucinase) than C. White SD improved intestinal architecture, cell proliferation and apoptosis, upregulated ZO1 and occludin tight junction proteins and stimulated goblet cell differentiation, enhancing the integrity of the mucosa barrier in both proximal and distal colonic mucosa in a better way than red SD. Consumption of SD significantly decreased serum triglyceride levels compared with the C diet. The mineral content of the right femur was not different among diets. The liver enzyme activities (superoxide dismutase, catalase, glutathione reductase, and glutathione peroxidase) did not show differences among diets. Liver reducing power and reduced glutathione/oxidize glutathione ratio were higher for animals consuming SD than C. It can be concluded that the consumption of precooked refined sorghum flours still has beneficial effects for health, mainly at the colonic level, despite the lower phenolics and fibre contents of refined flours with respect to whole grain flours.

Effects of extruded whole-grain sorghum (Sorghum bicolor (L.) Moench) based diets on calcium absorption and bone health of growing Wistar rats.

Apparent calcium absorption, total bone mineral content and density, and mineral contents of the right femur were studied using a growing rat model. Twenty-four male Wistar rats were fed with diets based on extruded whole grain red (RSD) or white sorghum (WSD), and control diet (CD) up to 60 days. The animals fed with sorghum diets consumed less and gained less weight compared to those fed with CD, but the efficiency of all diets was similar. Calcium intake was lower in animals fed with sorghum diets, related to the lower total intake of these animals. Apparent calcium absorption in animals fed with RSD was lower than in those fed with CD (CD: 72.7%, RSD: 51.0%, WSD: 64.8%). No significant differences in bone mineral density of total body, spin, femur, distal femur, tibia and proximal tibia were observed among the groups. However, Ca and P contents in the right femur of the rats consuming RSD were lower, indicating a certain imbalance in the metabolism of these minerals.

Modification of nutritional properties of whole rice flours (Oryza sativa L.) by soaking, germination, and extrusion.

Modifications of nutritional properties (amino acids, available lysine, protein digestibility, fatty acids, fiber, inositol phosphate (IPs), free and bound phenolics, and antioxidant properties) of whole rice ingredients processed by soaking, germination, and/or extrusion cooking were evaluated. Soaking and germination reduced proteins by lixiviation and hydrolysis, respectively. Lysine was the limiting amino acid. Polyunsaturated fatty acids increased after germination. Protein digestibility was 100% for germinated rice, decreased to 75% after the extrusion process. Fiber content decreased around 73% after the extrusion of soaked and germinated flours. Soaking-extrusion combined processes produces >50% IPs reduction. Germination-extrusion produced flours with the highest antioxidant capacity (54 µmol trolox g-1 ), which was in accordance with the highest content of free and bound phenolics (66 and 69 mg GA 100 g-1 , respectively). Grain treatments changed nutritional properties of flours resulting in low antinutrient whole grain ingredients, which could be used to develop whole grain-based foods. PRACTICAL APPLICATIONS: Phytic acid (PA) is an antinutrient having negative effects on mineral bioavailability and protein digestibility. There are processes such as soaking, germination, and extrusion, which alone or combined can decrease PA. However, nutritional composition and functionality of flours can change. We observed PA was highly reduced by soaking or germination combined with extrusion and antioxidant capacity and phenolic content increased in germinated and germinated-extruded flours compared to the other treatments. These modified whole grain rice flours low in anti-nutrients could be used in the production of expanded products or pre-cooked ingredients to develop whole grain based foods nutritionally improved.

Effects of the intake of white wheat bread added with garlic and resistant starch: action on calcium bioavailability and metabolic parameters of growing Wistar rats.

Wheat bread is a widely consumed food and is suitable for the introduction of functional ingredients. The aim of this work was to study the effects of bread with garlic and resistant starch as a fiber source on physiological, metabolic, and functional parameters using an in vivo Wistar rat model. Rats were fed with three diets: a control diet prepared according to the American Institute of Nutrition (C), and two semisynthetic diets containing wheat bread (B) and wheat bread with garlic, resistant starch and calcium citrate (BGR). Fresh feces were weighed and lactobacilli (L) and Enterobacteriaceae (E) were analyzed at different times: 1, 20, 45 and 60 days. The pH of the caecal content was recorded and at the end of the study changes in the bone mineral density of total skeleton (ts BMD), femur (F-BMD), spine (S-BMD) and tibia (T-BMD) were determined. Lipoprotein profile was assessed, atherogenic indexes were calculated and malonaldehyde content was measured in the serum and liver. In relation to gut microbiota, the BGR group showed an increase in the L/E ratio with respect to the other groups which was correlated with a lower cecal pH. Besides, the BGR group presented lower weight and a more favourable metabolic profile. In relation to bone measurements, the BGR group presented higher values of ts BMC, ts BMD, F-BMD, and T-BMD than the B group. Thus, bread with resistant starch, garlic and calcium citrate showed a prebiotic effect increasing calcium bioavailability and deposition in bones, compared with wheat bread. The observed beneficial health effects allow us to consider the design of healthier breads.

Análisis crítico del consumo de fructosa. Parte 2. Efectos metabólicos y traducción clínica del exceso de fructosa / Critical analysis of fructose consuption. Part 2. Metabolic effects and clinical translation of excess fructose

El Grupo de Trabajo Terapéutica Nutricional en Diabetes Mellitus de la Sociedad Argentina de Nutrición publicó en marzo de 2017 la primera parte de esta revisión en la cual se analizaron las fuentes de fructosa en la alimentación y los aspectos metabólicos básicos. En esta segunda parte se aborda la traducción clínica de los efectos más importantes para la salud. La revisión realizada permite concluir que ingestas superiores a 50 g/día aumentan los triglicéridos postprandiales, efecto no observado con cantidades equivalentes de glucosa. Esto promueve la remodelación de lipoproteínas a un perfil lipídico más aterogénico. La sacarosa y el jarabe de maíz de alta fructosa (JMAF) producen efectos similares a la fructosa sola. Respecto de la enfermedad del hígado graso no alcohólico, para cuyo desarrollo un balance energético positivo es una condición necesaria, la fructosa aumenta los niveles de enzimas de la lipogénesis de novo, uno de los mecanismos responsables de dicha alteración. La actividad lipogénica es mayor con fructosa que con glucosa, pero es aún mayor con el consumo simultáneo de ambos azúcares, como sacarosa o JMAF. También favorece la producción de ácido úrico, un efecto fructosa-específico, y a través de este mecanismo puede producir aumento de la presión arterial en relación dosis dependiente. La presión sistólica sufre mayores aumentos que la diastólica. A diferencia de las enfermedades analizadas previamente, los resultados hallados sobre la relación entre fructosa y obesidad no son concluyentes. Con respecto al desarrollo de diabetes tipo 2 ligado al aumento del consumo de azúcares se ha demostrado que el exceso de fructosa produce desarrollo de insulinorresistencia. Finalmente podemos destacar que no hay necesidad de agregar fructosa o azúcares a la alimentación. Al reducir la ingesta de azúcares al 5% de las calorías totales, como sugiere actualmente la Organización Mundial de la Salud (OMS), la tolerancia a la glucosa mejora y disminuye la prevalencia de diabetes y los desórdenes metabólicos que la preceden y acompañan.

The Diabetes Mellitus Nutritional Therapy Working Group of the Argentine Society of Nutrition published in March 2017 the first part of this review in which the sources of fructose in the diet and the basic metabolic aspects were analyzed. This second part addresses the most important health effects associated to excess fructose consumption. Intakes higher than 50 g/day increase postprandial triglycerides, leading to lipoproteins remodeling to a more atherogenic lipid profile. Sucrose and HFCS produce similar effects, whose are not observed with equivalent glucose amounts. Fructose may promote non-alcoholic fatty liver disease, for whose development, a positive energy balance is a necessary condition. Fructose increases the activity of de novo lipogenesis enzymes, one of the responsible mechanisms for this alteration. The lipogenic activity is higher with fructose than glucose, but it is even greater with the simultaneous consumption of both sugars, as sucrose or HFCS. Fructose may increases uric acid production, a fructose-specific effect, and through this mechanism, it can increases blood pressure in a dose-dependent relationship; the effect is greater for systolic than diastolic pressure. About the relationship between fructose and obesity, the results found are not conclusive. With regard to the development of type 2 diabetes -linked to increased sugar consumption-, usual fructose intake has demonstrated to produce insulin resistance. Finally, there is no need to add fructose or sugars to the food. Reducing sugars intake to 5% of total calories, as currently suggested by WHO, improves glucose tolerance and decreases the prevalence of diabetes and the metabolic disorders that precede and accompany it.

Colonic and systemic effects of extruded whole-grain sorghum consumption in growing Wistar rats.

Colonic effects of extruded whole-grain sorghum diets were evaluated using a model of growing rats. In all, twenty-four male Wistar rats were fed control (C), extruded white sorghum (EWS) or red sorghum (ERS). Consumption of sorghum diets showed satiety properties, with reduction of caecal pH, and lower activity of ß-glucosidase and ß-glucuronidase enzymes. Decreased copper zinc superoxide dismutase and manganese superoxide dismutase and increased catalase and glutathione peroxidase levels were observed in colonic mucosa. The induction of antioxidant enzymes occurred through the activation of the nuclear factor erythroid 2-related factor 2 protein and its subsequent translocation into the nucleus. ERS was able to decrease the proliferation of proximal mucosa of colon, demonstrating a possible effect against colorectal tumourigenesis. EWS increased proliferation and also apoptosis, ensuring the re-establishment of homoeostasis of the colonic mucosa. No antioxidant systemic effect (serum or hepatic level) was observed. It is likely that despite the extrusion the low bioavailability of the phenolic compounds of sorghum diets caused them to exert mainly acute effects at the colon level. Extruded whole-grain sorghum is a good functional ingredient that might be promising in dietary prevention of intestinal diseases.

Análisis crítico del consumo de fructosa Parte 1. La fructosa en la alimentación. Aspectos metabólicos / CRITICAL ANALYSIS OF FRUCTOSE CONSUMPTION PART ONE. THE FRUCTOSE ON NUTRITION. METABOLIC ASPECTS

La fructosa es un monosacárido presente naturalmente en las frutas y miel. Además, forma parte de la sacarosa y del denominado jarabe de maíz de alta fructosa (JMAF), que constituyen sus fuentes principales por la presencia en alimentos procesados. La fructosa tiene un metabolismo diferente al de la glucosa, y debido a su independencia de la insulina y a que produce menor modificación de la curva de glucemia, sumado a su elevado poder edulcorante, se la consideró una solución para el paciente diabético. Sin embargo, posteriormente surgieron estudios en los que se expusieron efectos metabólicos adversos, e incluso se la asoció con la epidemia de obesidad. Actualmente hay suficiente evidencia de que el consumo de fructosa produce ciertas acciones metabólicamente desfavorables cuando se la compara con glucosa. Entre estos efectos se señalan: aumento de TG en ayunas y postprandial, mayor producción de ácido úrico, aumento de la presión arterial, resistencia insulínica y mayor capacidad de glicación de proteínas. Es importante considerar que no se hallaron diferencias entre el consumo de sacarosa y de JMAF, lo que es lógico dada su similar composición. Los efectos del consumo de fructosa sobre la salud dependen de la cantidad consumida. Luego de la revisión podemos concluir que un consumo moderado de fructosa, menor a 50 g/día, no tendría efectos deletéreos sobre la salud. En este marco se destaca que el consumo de 1,5 litros de bebidas cola puede aportar entre 88 y 129 g de fructosa. Nuestro grupo de trabajo elaboró una tabla de contenido de fructosa en alimentos con el fin de contar con una herramienta que permita evaluar la presencia de fructosa en la alimentación. Se concluye además que sería recomendable que se declare el contenido de fructosa en el rótulo de los alimentos envasados, lo que facilitaría el manejo nutricional del paciente.

α-Galactosides present in lupin flour affect several metabolic parameters in Wistar rats.

The aim of this study is to evaluate the influence of α-galactosides present in a lupin diet on metabolic parameters in growing Wistar rats. Lupin (Lupinus albus) is a rich source of non-digestible carbohydrates called α-galactosides whose beneficial health effects have been widely reported. For our investigation, twenty male Wistar rats were fed with two different diets: control (C) and lupin flour (L) for a 60-day period. The fermentation of these α-galactosides was monitored by measuring the following indicators: changes in the dynamic lactobacilli and enterobacteriaceae population, cecal content pH, generation of short chain fatty acids (SCFA), Ca and P absorption, and serum lipid (triglycerides and cholesterol) contents. The body weight was lower in the L diet than that in the control with significant differences (p < 0.05). The microbial analyses showed an increase of total lactobacilli counts and a decrease of enterobacteriaceae counts in the L diet when compared to the control, with significant differences (p < 0.05). The fermentations of α-galactosides were also confirmed by decrease in pH levels and the formation of relevant SCFA in the cecal content. The total content of SCFA (µmol per g) at the end of the assay period reached values of 13.58 and 3.64 for L and C rats, respectively. This significant increase of total SCFA in the L diet is responsible for a low pH of the cecal content that in turn prevents the growth and development of potentially pathogenic bacteria (p < 0.05). Regarding lipids, serum triglycerides and cholesterol levels were significantly reduced in the case of animals fed with lupin flour with respect to C animals (p < 0.05). Finally, the L rats showed higher values of an apparent Ca absorption percentage and bone volume percentage with respect to the C animals (p < 0.05). All these results confirm that lupin flour which contains α-galactosides could possibly be considered as a functional ingredient with health promoting properties.

Extruded whole grain diets based on brown, soaked and germinated rice. Effects on cecum health, calcium absorption and bone parameters of growing Wistar rats. Part I.

The influence of diets with whole rice processed ingredients on cecum health, calcium absorption and bone parameters was studied using an animal model. Thirty-two male Wistar rats were fed with Control (C), extruded Brown rice (B), extruded Soaked whole rice (S) and extruded Germinated whole rice (G) diets for 60 days. The cecum weight, cecal content pH, cecal sIgA content, and ß-glucosidase and ß-glucuronidase activities were determined. Calcium apparent absorption, total bone mineral content and density and right femur parameters (ashes, organic content, calcium and P) were evaluated. The results showed that animals fed with whole grain diets have lower food intake in comparison with the C diet, and decreased cecal content pH (7.06 vs. 6.33) and ß-glucosidase activity (1.66 vs. 0.21 µmol p-nitrophenol g(-1) cc h(-1)). Even though calcium apparent absorption was not different among treatments (∼70%), none of the whole grain diets improved calcium related bone parameters over the control fed rats (cellulose as dietary fibre).

Extruded whole grain diets based on brown, soaked and germinated rice. Effects on the lipid profile and antioxidant status of growing Wistar rats. Part II.

The influence of whole grain (WG) rice based diets on the lipid profile and antioxidant status was evaluated. Thirty-two male Wistar rats were fed with Control (C), extruded Brown rice (B), extruded Soaked whole rice (S) and extruded Germinated whole rice (G) diets for 60 days. Triacylglycerols (TAGs), cholesterol and malondialdehyde equivalent (MDA eq.) in serum and liver were determined. Catalase (CAT), Glutathione Reductase (GR) and Glutathione Peroxidase (GPx) enzyme activities and Glutathione Reduced (GSH) and Oxidized (GSSG) in the liver were analyzed. Animals consuming B and S diets presented lower body weight gain. All WG diets reduced TAGs in serum and MDA eq. content in liver in comparison with the C diet. WG rice diets improved the redox status in animals mainly fed G due to their higher GR activity and GSH/GSSG ratio.

Wheat bread enriched with organic calcium salts and inulin. A bread quality study.

The objective of this work was to study quality parameters of enriched wheat bread with calcium citrate (Ca3CI2) or lactate (CaLA2) and inulin (In), also to optimize bread formulation. Fermentation time (tf), specific volume (Vs), browning index of crust (BI) and crumb properties (moisture, alveolus, texture) were studied. Generally, tf and Vs decreased with prebiotic increment. Ca3CI2 did not change Vs at equal inulin quantity, whereas with CaLA2 smaller breads were obtained (at 6.5 % In). Moisture of crumbs decreased with an increase in Ca3CI2 (at ≤ 6.5 %); while for CaLA2 was more influenced by the prebiotic. Up to 6.5 % In, the addition of both salts decreased crumb firmness and increased cohesiveness. Using a desirability function, the optimum calcium-prebiotic bread obtained with Ca3CI2 contained 2.40 g/kg Ca and 7.49 % In and with CaLA2 presented 1.33 g/kg Ca and 4.68 % In. Breads of high-quality with higher calcium and prebiotic quantity were able to obtain with Ca3CI2.

Effects of extruded whole maize, polydextrose and cellulose as sources of fibre on calcium bioavailability and metabolic parameters of growing Wistar rats.

The aim of this study was to evaluate the influence of diets with different types of fibres on Ca bioavailability and metabolic parameters in growing Wistar rats. Twenty four male Wistar rats were fed with 3 different diets: control (C), polydextrose (PD), and extruded whole maize (M) during a 60 day period. Apparent Ca absorption percentage (%Ca Abs), total skeleton bone mineral content (t BMC), total bone mineral density (t BMD), femur (F), spine (S) and tibia (T) BMD, cecum weight, and pH were evaluated. Malondialdehyde (MDA) and lipid (TG and cholesterol) contents in serum and liver were also evaluated. The results showed that rats fed with M and PD had the same cecum weight, but higher than that of C (1.53 ± 0.02 vs. 0.94 ± 0.01). There was moderate acidification of the cecal content in rats fed with M compared to C (pH 5.93 vs. 6.98) and the fecal weight was 1.06 ± 0.02, 3.07 ± 0.03 and 4.81 ± 0.05 for PD, M and C, respectively. There were significant differences in %Ca Abs between PD and C (87.57 ± 1.20 vs. 71.10 ± 1.11). The PD group had the highest values of F-BMD, S-BMD, and T-BMD, but there were no differences between M and C groups. Regarding lipids, there was a significant lowering effect in the M liver triglycerides content. Moreover, liver MDA levels significantly decreased with M and PD diets. The consumption of PD and grain fibres can exert some beneficial gastrointestinal effects such as lowering of the pH, hepatic TG and MDA content related to fibre colon fermentation.

Polydextrose Enhances Calcium Absorption and Bone Retention in Ovariectomized Rats.

Purpose. To evaluate the effect of polydextrose (PDX) on Ca bioavailability and prevention of loss of bone mass. Methods. Twenty-four two-month-old ovariectomized rats were fed three isocaloric diets only varied in fiber source and content up to 60 days (FOS group, a commercial mixture of short- and long-chain fructooligosaccharide, OVX group fed AIN 93 diet, and PDX group). A SHAM group was included as control. Apparent Ca absorption percentage (%ABS), changes in total skeleton bone mineral content (tsBMC) and bone mineral density (BMD) and femur BMD, % Bone Volume, Ca and organic femur content, caecal weight, and pH were evaluated. Results. %ABS and caecum weight of PDX and FOS were higher, and caecum pH was lower compared to OVX and SHAM. PDX reached a higher pH and lower caecum weight than FOS possibly because PDX is not completely fermented in the colon. Changes in tsBMC and femur BMD in FOS and PDX were significant lower than SHAM but significantly higher than OVX. % Bone Volume and femur % of Ca in PDX were significantly higher than OVX and FOS but lower than SHAM. Conclusions. PDX increased Ca absorption and prevented bone loss in OVX rats.

Diseño de panes funcionales a base de harinas no tradicionales / Design of functional breads based on non-traditional flours

Functional breads constitute an interesting alternative as a vehicle of new dietary fiber sources. Two ingredients which are obtained and used at regional levels were studied: green banana flour (GBF) (Musa acuminata var nanica) and American carob flour (CF) (Prosopis alba). Breads were made mixing these flours with wheat flour (WF): GBF/WF 50:50 and CF/WF 25:75. Proximal composition of all samples was assessed according to AOAC methods. Iron, zinc and calcium contents were determined by AAS and mineral dialyzability using an in vitro method. The studied flours as well as the breads were characterized by high dietary fiber contents (12.4 and 31.0 in GBF and CF; and 6.9 and 10.2 in the green banana and carob breads, respectively). Breads had about 22% less available carbohydrates than white bread. Mineral dialyzability increased in breads about 30 to 50%, since fermentation promotes phytates degradation. The greatest effect was observed on iron dialyzability. These results indicate that these flours might be promising ingredients for use in the design of functional breads, with important levels of dietary fiber. These breads may be labeled as high fiber products according to current national regulations (minimum 6%). The inclusion of CF contributed to higher iron and calcium levels while the use of GBF, due to its functional properties, allowed for a greater replacement of wheat flour.

Los panes funcionales representan una alternativa interesante como vehículo de nuevas fuentes de fibra. Se estudiaron materias primas cuya obtención y uso es aún de tipo artesanal: la harina de banana verde (HBV) (Musa acuminata var nanica) y la harina de algarroba (HA) (Prosopis alba). Se elaboraron panes en mezcla con harina de trigo (HT): HBV/HT 50:50 y HA/HT 25:75. La composición centesimal de todas las muestras se realizó según AOAC. Se determinó el contenido de hierro, zinc y calcio por EAA y la dializabilidad mineral por un método in vitro. Tanto las materias primas como los panes se caracterizaron por un alto contenido de fibra (12,4 y 31,0 para HBV y HA y 6,9 y 10,2 para los panes de harina de plátano y algarroba respectivamente). Los panes presentaron alrededor de 22% menos de carbohidratos disponibles que el pan blanco. La dializabilidad de minerales se incrementó en los panes entre un 30 y un 50% ya que la fermentación promueve la degradación de los fitatos. El mayor efecto se observó sobre la dializabilidad de hierro. Estos resultados señalan a estas harinas como ingredientes promisorios para su utilización en el diseño de panes funcionales, con un importante aporte de fibra dietaria, que permite considerarlos alimentos ricos en fibra, de acuerdo a la legislación vigente (Código Alimentario Argentino) que señala un mínimo de 6% para dichos productos. La inclusión de HA contribuyó a un mayor aporte de hierro y calcio, mientras que la de HBV, por sus características funcionales, permitió un mayor reemplazo de harina de trigo.

Chemical composition and nutritional value of unripe banana flour (Musa acuminata, var. Nanicão).

Banana flour obtained from unripe banana (Musa acuminata, var. Nanicão) under specific drying conditions was evaluated regarding its chemical composition and nutritional value. Results are expressed in dry weight (dw). The unripe banana flour (UBF) presented a high amount of total dietary fiber (DF) (56.24 g/100 g), which consisted of resistant starch (RS) (48.99 g/100 g), fructans (0.05 g/100 g) and DF without RS or fructans (7.2 g/100 g). The contents of available starch (AS) (27.78 g/100 g) and soluble sugars (1.81 g/100 g) were low. The main phytosterols found were campesterol (4.1 mg/100 g), stigmasterol (2.5 mg/100 g) and ß-sitosterol (6.2 mg/100 g). The total polyphenol content was 50.65 mg GAE/100 g. Antioxidant activity, by the FRAP and ORAC methods, was moderated, being 358.67 and 261.00 µmol of Trolox equivalent/100 g, respectively. The content of Zn, Ca and Fe and mineral dialyzability were low. The procedure used to obtain UBF resulted in the recovery of undamaged starch granules and in a low-energy product (597 kJ/100 g).

Fermented milk-starch and milk-inulin products as vehicles for lactic acid bacteria.

Formulations using cassava starch or inulin plus milk were fermented with three different lactic acid bacteria (LAB) strains: Lactobacillus plantarum D34, Lactobacillus sp. SLH6, and Streptococcus thermophilus ST4. Growth and acidification were followed in 3% powdered milk (M3), 3% milk-6% starch (M3-S6), and 3% milk-6% inulin (M3-In6). D34 and SLH6 growth was enhanced by starch in M3-S6, when compared to the count (CFU/ml) obtained in M3. Growth of all strains was promoted by inulin. All fermented products showed LAB counts of 8.0 log or higher. Carbohydrate utilization was in agreement with growth and acidification results. The highest increase in CFU in rat feces was observed in M3-S6 fermented with ST4; the D34 fermented product also increased CFU but SLH6 did not, either with starch or inulin. This suggests that ST4 and D34 strains provide a good choice to ferment the proposed formulations in order to obtain a marked improvement of natural intestinal flora.