Neutral detergent fibre in piglet diets: digestibility, performance, and deposition of body nutrients

ABSTRACT A total 120 piglets with an average live weight of 7.00 kg, weaned at 21 days, were used to evaluate the effect of neutral detergent fibre levels on the digestibility of nutrients and energy from the diets, productive performance, and the composition and rate of deposition of nutrients and energy in the bodies of piglets in the nursery phase. The animals were distributed according to a randomized-block design into five treatments, which consisted of neutral detergent fibre levels, with six replicates and four animals per plot. A quadratic effect was detected for the digestibility coefficients of nutrients and energy, feed intake and weight gain. The increase in fibre level promoted a linear increase in fat content in the carcass, blood, and body, whereas the energy in the carcass, organs, and body showed an inverse response. The results showed a quadratic effect on the nutrient deposition rate in the carcass, organs and body. In conclusion, the best digestibility of nutrients and energy from the diet is obtained with 10-11.5% neutral detergent fibre, as higher weight gain and greater protein deposition in the body are achieved at neutral detergent fibre levels of 10.6% and 10.3%, respectively.

Efeito hipolipemiante da suplementação dietética com a farinha do cubiu (Solanum sessiliflorum Dunal) em ratos hipercolesterolêmicos / Hypolipidemic effect of diet supplementation with cocona (Solanum sessiliflorum Dunal) flour in hypercholesterolemic rats

Estudos com frutas e vegetais ricos em fibra alimentar tem demonstrado efeito redutor das concentrações sanguíneas de colesterol total, atuando de forma preventiva contra a hipercolesterolemia. O objetivo do presente trabalho foi analisar a composição química da farinha de cubiu e avaliar o efeito de seu consumo sobre a lipemia de ratos hipercolesterolêmicos. Foram utilizados 8 animais para cada tratamento, em 7 grupos sendo: 1 controle; 3 experimentais com 5%, 25% e 50% da recomendação de fibras (AIN-93) provenientes da farinha de cubiu; e 3 grupos per feeding tendo celulose e pectina como fonte de fibra alimentar nas mesmas proporções dos grupos experimentais. Ao final do ensaio foi verificado que não houve variação significativa no consumo de ração pelos animais e no ganho de massa corporal no decorrer do experimento. Os tratamentos com farinha de cubiu reduziram as concentrações de colesterol total (-21,6%), LDL-c (-56,8%), aumentaram a excreção de colesterol fecal (+116%), e diminuíram o colesterol hepático (-32,1%). Nenhum dos tratamentos promoveu alteração significativa nas concentrações de triglicerídeos. Os tratamentos com pectina e celulose demonstraram resultados semelhantes aos do cubiu. Os resultados observados servem como base para futuros estudos visando o aproveitamento biotecnológico deste fruto.

Studies with fruit and vegetables rich in dietary fiber have shown lowering effects on the blood concentrations of total cholesterol (TC), acting preventively against hypercholesterolemia. The aim of this study was to analyze the chemical composition of cocona and evaluate the effect of the consumption of cocona flour on lipemia of Wistar rats with hypercholesterolemia. Eight animals were used for each treatment, in 7 groups: control; 3 experimental groups with 5%, 25% and 50% of the recommended fiber (AIN-93) from cocona flour; 3 groups per feeding with pectin and cellulose as source of dietary fiber, in the same proportions of the experimental groups. At the end of the assay, we verified that there were not significant variations in the consumption of the animals and the body weight during the experiment. Treatments with cocna flour were responsible for reducing the concentrations of total cholesterol (-21.6%), LDL-c (-56.8%), increasing the excretion of fecal cholesterol (+116%) and lowering the liver cholesterol (-32.1%). None of the treatments significantly altered the triglyceride concentrations. Treatments using pectin and cellulose show results similar to cocona. The observed results can be used in further studies aimed at the biotechnological exploitation of this fruit.

Effects of fat replacement on properties of whole wheat bread

Bread characteristics are dependent upon the chemical composition and fiber content of the wheat flour used. A healthy diet can help prevent chronic diseases, where whole grains and fewer calories from fat are components of a healthy diet. The aims of this study were to determine the centesimal composition of wheat flour samples (whole, refined, and flour blends) along with their farinographic parameters (water absorption, development time and stability) and also to verify the specific volume, crumb texture profile and digital imaging of bread loaves made with 60% whole wheat flour and 3% fat or fat replacer. Increasing the whole wheat flour percentage in the blends also increased levels of protein, ash and insoluble fiber. All the farinographic parameters were also increased. Enzymatically modified starch was found to be an effective fat replacer in whole wheat loaves. The loaves made using fat replacer had the same specific volume and higher cell density as those made with fat, but exhibited different texture profile parameters such as higher hardness value and lower springiness value.

A composição química da farinha de trigo e a presença de fibras afeta as características dos pães. Uma forma de contribuir com a prevenção de doenças crônicas não transmissíveis é através de alimentação saudável, incluindo grãos integrais na dieta alimentar e reduzindo as calorias de determinado alimento, substituindo a gordura. Assim, este trabalho tem como objetivo determinar a composição centesimal das amostras de farinha de trigo integral, refinada e as misturas entre elas; bem como os parâmetros farinográficos (absorção de água, tempo de desenvolvimento e estabilidade) das mesmas. Além disso, verificar volume específico, perfil de textura do miolo e análise de imagem de pães elaborados com 60% de farinha de trigo integral e com 3% de gordura ou com substituto de gordura. Os dados foram submetidos à análise de variância. À medida que aumenta o percentual de farinha integral, os teores de proteína, cinzas e fibra insolúvel alcançam valores significativamente maiores e a absorção de água fica maior na farinografia, bem como o tempo de desenvolvimento e a estabilidade. O amido modificado enzimaticamente utilizado na elaboração de pão com 60% de farinha de trigo integral funcionou como um efetivo substituto de gordura. O pão integral elaborado com substituto de gordura apresentou volume específico significativamente igual ao pão integral elaborado com gordura, porém com diferenças em relação a parâmetros do perfil de textura, maior firmeza e menor elasticidade além de maior densidade celular do que o pão elaborado com gordura.

La cascarilla de la soja: potencial componente de alimentos funcionales / Soybean hull: potential ingredients for functional foods

The effects of soybean bran, a residue of soybean oil extraction, rich in dietary fiber-both soluble and insoluble -on fat distribution, plasmatic and liver lipids, glycemia and glycemic load, were studied on adult male obese diabetic 0 rats. Two hundred days old ft rats were fed two diets with 15 percent sodium caseinate as protein source and 10 percent dietary fiber from soybean bran (S) or cellulose (C) during 30 and 60 days. Significant diminutions in blood cholesterol levels were registered in group S on day 30 as well as on day 60. Diet S significantly attenuated the characteristic increase in blood triacylglycerols levels and the usual progressive increase in blood glucose levels expressed in this line of rats. Diet S decreased significantly liver total lipids, cholesterol and triacylglycerols compared with C. No differences were registered between groups neither in food intake nor in biomass. These effects are attributed to the combined effects of the soluble and insoluble fiber fractions present in soybean bran. In conclusion, soybean bran may be considered as a useful component of functional foods designed for human nutrition.

Se estudiaron los efectos de la cascarilla o salvado de la soja, con alto contenido de fibra dietaria, de tipo insoluble y soluble, sobre la distribución del tejido adiposo, el perfil lipídico sanguíneo y hepático, la glicemia basal y post sobrecarga glucídica, en ratas adultas de la línea IIMb/p, obesa y diabética. Ejemplares de 200 días fueron alimentados durante 30 y 60 días con dos dietas con caseinato como fuente proteica y 10 g/100g de fibra de salvado de soja (S) o celulosa microcristalina (C). Tanto a los 30 como a los 60 días de tratamiento se constataron niveles de colesterol sérico significativamente menores en el grupo S con respecto a C. Los valores de C fueron asimismo superiores a los del inicio del experimento. La dieta S atenuó el aumento de los triacilgliceroles séricos, manifestado en el grupo C y el progresivo aumento de la glucemia basal habitual en estos roedores. Se registró una significativa disminución de los lípidos totales, el colesterol y los triacilgliceroles hepáticos en el grupo S. Se atribuyen estos efectos, a los mecanismos fisiológicos combinados de las fracciones de fibra del salvado de la soja. Se concluye que este producto podría evaluarse en humanos como un potencial componente de alimentos funcionales.

Efecto de un yogur con inulina sobre la función intestinal de sujetos sanos o constipados / Effect of an inulin containing yougurt on intestinal function of healthy and constipated volunteers

The effect of the consumption of a yogurt with 2.36 g inulin and 1.77g polydextrose was evaluated in 33 healthy and 37 constipated adults, compared with the same product without inulin. The study includes two 5-week periods, one with the experimental product and the other with the control product, separated by a three week wash-out. The subjects had to ingest 1 yougurt/day during the first week of each period, 2/day during the third week and 3/day during the fifth week; simultaneously they had to register daily the intensity of the digestive symptoms as well as the frequency and consistency of their stools. The results showed that in healthy subjects, the intake of 2 yogurts with inulin or more per day significantly increased the digestive symptoms (p=0.03), due to a greater emission of rectal gas (p=0.000). Similar findings were observed in the constipated subjects consuming 3 yogurts daily (p=0.0085 y p=0.0048, respectively); stool frequency and consistency were significantly improved in these subjects (p=0.0039 and p=0.014, respectively). These results suggest that the consumption of 2 yogurts with inulin by day help to fight constipation in subjects with this complain while the intake of this same amount may increase discomfort in healthy subjects.

En 33 adultos sanos y 37 constipados se evaluó el efecto del consumo de un yogur que contenía 2.36 g de inulina y 1.77 g de polidextrosa, en comparación con un yogur control sin inulina. El estudio incluyó dos períodos de 5 semanas separados por tres semanas de reposo: uno con el producto experimental y otro con el control. Los sujetos consumieron 1 yogur al día la primera semana de cada período, 2 al día en la tercera y 3 al día en la quinta, y anotaron diariamente la intensidad de los síntomas digestivos así como el número de deposiciones emitidas y su consistencia. Los resultados muestran que a partir de un consumo diario de 2 yogures con inulina existe un aumento significativo de la sintomatología digestiva en los sujetos sanos (p=0.03), debido principalmente a la mayor emisión de gases rectales (p=0.000). Observaciones similares se realizaron en los sujetos constipados con el consumo de 3 productos diarios (p=0.0085 y p=0.0048, respectivamente); sin embargo en aquellos se observó además un mejoramiento significativo tanto en la frecuencia de las deposiciones (p= 0.0039) como en su consistencia (p= 0.014). Este estudio sugiere que el consumo del producto con inulina contribuye a aliviar las molestias de los individuos constipados pero que en los sujetos sanos un consumo de dos yogur al día aumenta los síntomas desagradables.

Effect of soluble fiber or fructooligosaccharide supplementation upon trinitrobenzenesulphonic acid induced colitis in rats / Efeito da suplementação de fibra solúvel ou frutooligossacarídeo na colite induzida por ácido trinitrobenzenossulfônico em ratos

PURPOSE: To evaluate the effect of soluble fiber or fructooligosaccharide (FOS) supplementation upon trinitrobenzene sulphonic acid (TNBS)-induced colitis in rats. METHODS: 64 Wistar rats were given water, soluble fiber or FOS intragastrically during 14 days prior to colitis induction with TNBS (n=48) or rectal enema with water (n=16; control group). On the 7th or 14th day following colitis induction the rats were weighed and euthanized in order to determine the colon weight/length ratio and macroscopic and microscopic scores. RESULTS: On the 7th day following colitis induction the body weight had decreased significantly, the colon weight/length ratio had increased and macroscopic and microscopic colon lesions were observed. On the 14th day following colitis induction no difference in body weight was observed, in spite of the persistence of macroscopic and microscopic lesions and increased colon weight/length ratio. Supplementation with soluble fiber or FOS did not revert colon lesions or any of the study parameters. Supplementation with FOS, but not with fiber, was associated with increased colon weight/length ratio on the 14th day. CONCLUSION: Supplementation with soluble fiber or FOS produced no significant impact on TNBS-induced colitis in rats.

OBJETIVO: Avaliar a suplementação de fibra solúvel ou frutooligossacarídeos (FOS) na colite induzida por TNBS em ratos. MÉTODOS: Sessenta e quatro ratos Wistar receberam por gavagem água, fibra solúvel ou FOS. Após 14 dias, foram submetidos à indução de colite com TNBS. O grupo controle recebeu água por gavagem e por enema retal. Decorridos 7 ou 14 dias, após a avaliação do peso, os ratos foram sacrificados e o peso do colo, escores macroscópicos e microscópicos da lesão cólica foram aferidos. RESULTADOS: No 7° dia após indução da colite, houve uma significativa diminuição do peso dos ratos, um aumento do peso do cólon e lesão cólica macroscópica/microscópica. A suplementação com fibra ou FOS não reverteu nenhum destes parâmetros. No 14° dia após a indução da colite não foram observadas diferenças no peso dos ratos, entretanto houve uma persistência da lesão cólica macroscópica/microscópica e do aumento do peso do cólon. A suplementação com fibra ou FOS não reverteu à lesão cólica. A suplementação de FOS, mas não de fibra, aumentou o peso do colo comparado com o grupo colite no 14° dia. CONCLUSÃO: A suplementação com fibra solúvel ou com FOS não alterou a colite por TNBS em ratos.

A ação da fibra dietética solúvel (Ispaghula Husk) na preservação da densidade volumétrica da parede colônica irradiada: estudo experimental em ratos / The action of the soluble dietary fiber (Ispaghula Husk) in the preservation of the volumetric density of the radiated colonic wall: experimental study in rats

Introdução: os efeitos deletérios da radiação ionizante na parede colônica constituem um significante obstáculo à utilização desse método. Trabalhos científicos têm creditado à fibra dietética efeitos positivos sobre o trofismo intestinal. Objetivo: o objetivo deste estudo foi a análise da ação da suplementação de fibras dietéticas solúveis na preservação da densidade da parede do cólon de ratos irradiados. Material e método: foram utilizados 30 ratos machos adultos da raça Wistar, com peso variando de 250-300g, divididos em três grupos de estudo. O primeiro grupo (Grupo Controle) foi constituído de 10 animais sadios, alimentados com ração própria para a espécie. O segundo grupo (Grupo Controle Irradiado), composto por 10 animais, foi alimentado com ração própria para a espécie durante todo o período e submetido à irradiação de fração única de 10Gy no oitavo dia de experimentação. O terceiro grupo (Grupo Irradiado Sob Fibra), composto por 10 animais, foi alimentado durante todo o período com ração enriquecida com fibra solúvel (Ispaghula husk) e submetido à irradiação de fração única de 10Gy no oitavo dia de experimentação. Todos os animais foram sacrificados no décimo quinto dia de experimentação e submetidos a laparotomia para a ressecção do segmento distal do cólon. As peças foram processadas e submetidas à análise estereológica e estatística (teste não paramétrico de Mann-Whitney). Foram analisados os seguintes parâmetros morfométricos: volume da mucosa, volume da muscular da mucosa, volume da submucosa, volume da muscular própria, volume parcial do epitélio e volume parcial da lâmina própria. Resultados: observamos a diminuição da espessura da parede colônica no grupo II, com diminuição do volume parcial do epitélio e aumento do volume parcial da lâmina própria quando comparado ao grupo I. A espessura da parede colônica aumentou significativamente no grupo III em relação ao grupo I, sem, contudo, alterar o volume parcial de cada camada em relação ao volume total da parede. Conclusão: concluímos que a suplementação dietética de fibra solúvel é capaz de promover a hipertrofia global da parede colônica, porém não evita a diminuição do volume parcial do epitélio e o correspondente aumento do volume parcial da lâmina própria.

Efeito da fibra do polissacarídeo de soja no peso e na umidade das fezes de ratos em fase de crescimento / The effect of soy polysaccharide fiber on fecal weight and humidity in growing rats

OBJETIVO: Comparar, em ratos, o efeito do polissacarídeo de soja em relação a celulose e fórmula de soja sem fibra alimentar sobre o peso e a umidade fecal. MÉTODOS: Foram utilizados 12 ratos Wistar machos, com 21 dias de vida, distribuídos em três grupos, que receberam ração AIN-93G variando-se a fonte de fibra alimentar: grupo polissacarídeo, com 5 por cento de fibra na forma de polissacarídeo de soja; grupo fórmula de soja, com 5 por cento de fórmula de soja sem fibra; e grupo celulose, com 5 por cento de fibra na forma de celulose. As fezes foram coletadas em três períodos de 72 horas iniciados no 7º, 17º e 27º dia. As mesmas foram pesadas frescas e após secagem em estufa a 105 ºC até peso constante. A umidade foi calculada usando a fórmula [(peso fecal úmido - peso fecal seco)/peso fecal úmido] x 100. RESULTADOS: As somas do peso fecal úmido nos grupos polissacarídeo, fórmula de soja e celulose foram, respectivamente: 17,372±4,743 g; 6,045±0,619 g; 16,012±2,600 g (p = 0,001), observando-se diferença estatisticamente significante dos grupos celulose e polissacarídeo em relação ao grupo fórmula de soja. Não houve diferença estatisticamente significante entre os grupos celulose e polissacarídeo. Para o peso seco, na mesma ordem, observou-se: 6,463±1,177 g; 2,909±0,277 g; 10,068±1,085 g (p < 0,001), com diferença estatisticamente significante entre todos os grupos. CONCLUSAO: Os animais que receberam fórmula de soja apresentaram peso fecal úmido e seco inferior ao dos outros dois grupos, enquanto o polissacarídeo de soja determinou umidade fecal superior à da celulose, provavelmente por maior fermentação no cólon.

Dietary fibre and coronary heart disease.

Intake of dietary fibres lowers plasma lipids. Fibres particularly soluble ones lower serum total cholesterol (TC) and serum low-density lipoprotein cholesterol (LDL-C) without significant alteration in serum high-density lipoprotein cholesterol (HDL-C) and triacylglyccrol (TG). Consequently, the incidence of atherosclerotic heart diseases is lower in those who take high dietary fibre. Persons taking diet rich in saturated fat and poor in dietary fibre is more prone to develop coronary artery diseases. Dietary fibres also lower TC: HDL-C and LDL-C: HDL-C ratios. Higher TC: HDL-C and LDL-C: HDL-C ratios are in favour of development and progression of atherosclerotic vascular diseases, a pioneer cause of myocardial infarction (MI).

Protective effect of dietary fibers against colorectal carcinoma.

Dietary fibers are remnant of plant cells resistant to hydrolysis by human alimentary tract enzymes. These are cellulose, hemicellulose, lignin, pectins and gums. Intake of dietary fibers or foods rich in dietary fibers decreases the incidence of colorectal carcinoma. Reduced risk of colorectal carcinoma is reported when populations with diet high in red meat and total fats switched to a diet high in total fibers and certain whole grain, goods. Fibre intake is also inversely related to mortality from colorectal carcinoma. Beneficial influence of most vegetables and fruits against colorectal carcinoma is confirmed and this is due to their fibre contents.

Effects of different levels of coconut fiber on blood glucose, serum insulin and minerals in rats.

The effect of neutral detergent fiber (NDF) from coconut kernel (Cocos nucifera L) in rats fed 5%, 15% and 30% level on the concentration of blood glucose, serum insulin and excretion of minerals was studied. Increase in the intake of fiber resulted in significant decrease in the level of blood glucose and serum insulin. Faecal excretion of Cu, Cr, Mn, Mg, Zn and Ca was found to increase in rats fed different levels of coconut fiber when compared to fiber free group. The result of the present investigation suggest that inclusion of coconut fiber in the diet results in significant hypoglycemic action.

Hypolipidemic effect of hemicellulose component of coconut fiber.

The neutral detergent fiber (NDF) isolated from coconut kernel was digested with cellulase and hemicellulase and the residual fiber rich in hemicellulose (without cellulose) and cellulose (with out hemicellulose) were fed to rats and compared with a fiber free group. The results indicate that hemicellulose rich fiber showed decreased concentration of total cholesterol, LDL + VLDL cholesterol and increased HDL cholesterol, while cellulose rich fiber showed no significant alteration. There was increased HMG CoA reductase activity and increased incorporation of labeled acetate into free cholesterol. Rats fed hemicellulose rich coconut fiber produced lower concentration of triglycerides and phospholipids and lower release of lipoproteins into circulation. There was increased concentration of hepatic bile acids and increased excretion of faecal sterols and bile acids. These results indicate that the hemicellulose component of coconut fiber was responsible for the observed hypolipidemic effect.

Glycaemic and insulinaemic responses to natural foods, frozen foods and their laboratory equivalents.

Glycaemic response to a food is determined by a large number of factors, of which composition is only one. The present study was designed to study the effect of composition and overnight refrigeration on the glycaemic response. The study involved determination of the glycaemic and insulinaemic response of healthy human volunteers to rice or potato, and to meals equivalent to these foods in terms of carbohydrate, protein, fat and fibre content; but made up of cornflour, casein, corn oil and cellulose. Further, each of these meals was served either freshly cooked, or after overnight storage in a refrigerator and rewarming. The natural foods led to a higher postprandial glycaemia than their respective equivalents, and the freshly cooked foods led to a higher glycaemic response than the refrigerated and rewarmed forms of the corresponding foods. No such consistent differences were observed in case of the insulinaemic responses. The difference in the glycaemic response to foods and their laboratory equivalents may be due to the unique physical arrangement of nutrients within the food or due to specific chemical differences in terms of macro-or micro-nutrients, non-nutrients or anti-nutrients. The difference in the glycaemic response to freshly cooked and refrigerated foods may be due to the formation of resistant starch during cold storage.

Efectos de la fibra dietética sobre la digestibilidad de las proteínas y de la energía en ratas / Effect of the dietary fiber on protein and energy digestibilities rats

Se realizó un balance nitrogenado y de energía en ratas para determinar la influencia del nivel de fibra dietética sobre la digestibilidad de las proteínas y de la energía de 25 productos vegetales. Se tomó en consideración la presencia de inhibidores de tripsina, lectinas y polifenoles en algunos de estos productos. Cinco muestras se ensayaron crudas y calentadas. Se encontró una relación inversa significativa entre el nivel de fibra dietética y la digestibilidad de las proteínas y de la energía. La presencia de inhibidores de tripsina, lectinas y polifenoles y el proceso de calentamiento no pareció ejercer ninguna influencia. La fibra dietética fue el factor más importante asociado con la digestibilidad de las proteínas y de la energía en estas muestras

Efeito da fibra alimentar sobre os níveis de colesterol, HDL-Colesterol e Triaciglicerol Serico / Effect of the fiber ingestion over the cholesterol, HDL-Cholesterol and Triglyceride

Foi avaliado o efeito da fraçao fibra (pectina e lignina)e fonte de fibra (fibrax) em dietas ricas ou pobres em colesterol sobre os níveis séricos de colesterol, HDL-COL, e triacilglicerol de ratos. Foram aplicados 8 tipos de raçöes: 2 grupos controle (sem fibra, com ou sem a adiçao de 1g por cento de colesterol) e 6 grupos testes (com 5g por cento de lignina ou 5g por cento de pectina ou 10g por cento de fibrax, com ou sem adiçäo de 1g por cento de colesterol). O experimento foi realizado por 42 dias, utilizando 56 ratos. Ao final desse período, os ratos foram anestesiados e coletado o sangue por punçäo cardíaca. Pectina baixou o colesterol sérico, porém quando a dieta era rica em colesterol apresentou baixos níveis de HDL-COL. Lignina com colesterol dietético baixou o colesterol e HDL-COL sérico. Fibrax aumentou o colesterol sérico, porém baixou o triacilglicerol quando era adicionado colesterol dietético na raçäo. Dieta rica em colesterol, obteve menor nível de HDL-COL, em dietas isenta de fibra alimentar.

Nutrient interaction in relation to glycaemic and insulinaemic response.

Although it is known that protein, fat and fibre reduce the postprandial glycaemia following an oral carbohydrate load, the nature and extent of interaction of different nutrients with one another in this respect is not well understood. The present study was designed to explore systematically the glycaemic and insulinaemic response to glucose (G) alone, or in combination with one or more of the following: casein (CS), maize oil (MO), cellulose (CL) and pectin (P). Besides 100 g G, eleven isoenergetic and six isocarbohydrate meals were studied on healthy adult males using an incomplete block design. Addition of other nutrients to G led to a lowering of the glycaemic response. The lowest glycaemic responses were seen in case of meals containing the largest number of nutrients. P was more effective in reducing postprandial glycaemia than CL. As in case of glycaemic response, low insulinaemic responses were also associated with P-containing meals, and meals containing the largest number of nutrients. But unlike in case of glycaemic response, there was a tendency for elevation of the insulinaemic response in case of CL-containing meals. The degree of attenuation of glycaemic response observed with meals containing several nutrients was roughly predictable on the basis of the attenuation observed with meals in which only one nutrient had been added at a time to G. But the glycaemic response of natural foods is unlikely to be predictable on the basis of their nutrient composition because of the overriding influence of several other factors such as physical form, cooking, processing, storage and antinutrient content of the food.

Dietary fiber and lipid peroxidation: effect of dietary fiber on levels of lipids and lipid peroxides in high fat diet.

Effect of feeding coconut and blackgram fiber isolated as neutral detergent fiber (NDF) on the levels of lipids and lipid peroxides was studied in rats given a high fat diet. Concentration of cholesterol, free falty acid and phospholipids showed significant decrease in the serum, liver aorta and intestine of coconut and blackgram fiber groups. Concentration of malondialdehyde (MDA) and conjugated dienes was significantly decreased in liver and intestine of both fiber groups, while hydroperoxides showed significant increase in liver and heart of both the fiber groups. SOD and catalase activity was found to be increased in liver, intestine, heart proximal colon and distal colon of both the fiber groups. Serum ceruloplasmin levels showed a slight increase in animals fed coconut and blackgram fiber groups. Glutathione levels in liver, intestine proximal colon, distal colon and heart also showed a significant decrease in the animals of both the fiber groups.

Aortic/glycosaminoglycans alterations in antiatherogenic action of dietary fiber from unripe banana (Musa paradisiaca).

Dietary fiber isolated as neutral detergent residue from unripe banana altered the concentration of aortic glycosaminoglycans in rats fed cholesterol free and cholesterol diet. Concentration of hyaluronic acid (9.9%), heparan sulphate (53.4%), chondroitin 4-sulphate (32.6%), chondroitin 6-sulphate (17.9%), dermatan sulphate (18.8%) and heparin (10.1%) increased in the aorta in rats fed cholesterol free diet. In rats fed cholesterol diet, concentration of heparan sulphate (23.3%), chondroitin 4-sulphate (9.8%) and heparin (42.4%) increased while hyaluronic acid showed a decrease (29.7%). The activity of beta-glucuronidase (9.5%) and beta-hexosaminidase (19.7%) decreased in the aorta in rats fed cholesterol free diet and given dietary fiber, while only beta-hexosaminidase (19.3%) decreased in rats fed cholesterol diet.