Sugar beet pulp and apple pomace dietary fibers improve lipid metabolism in rats fed cholesterol

The effect of diets supplemented with sugar beet pulp fiber (SBP, 10%) and apple pomace fiber (AP, 10%) on lipids and lipids peroxides was investigated in 60 male Wistar rats. The rats were divided into six groups of 10 and adapted to cholesterol-free or 0.3% cholesterol diets. The basal diet (BD) contained wheat meal, barley meal, wheat hulls, meat-bone meal, barley sprouts, skimmed milk, fodder yeast, mineral and vitamin mixtures. The Control group (Control) consumed BD only. To the BD were added 3 g/kg cholesterol (Chol), 100 g/kg dry sugar beet pulp fiber (SBP), both 100 g/kg sugar beet pulp fiber and 3 g/kg cholesterol (SBP+Chol), 100 g/kg apple pomace fiber (AP), both 100 g/kg apple pomace fiber and 3 g/kg cholesterol (AP+Chol). The experiment lasted 40 days. Plasma total cholesterol (TC), LDL cholesterol (LDL-C), HDL cholesterol (HDL-C), triglycerides (TG), total phospholipids (TPH), HDL phospholipids (HDL-PH), lipid peroxides (LP) and liver TC concentration were measured. Groups did not differ before the experiment. In the Chol+SBP and the Chol+AP vs. Chol group the sugar beet pulp and apple pomace dietary fiber supplemented diet significantly (P<0.05) hindered the rise of plasma lipids: (a) TC−2.97 vs. 3.69 mmol/l, −20% and 3.01 vs 3.69 mmol/l, −18.4%, respectively; (b) LDL-C −1.36 vs. 2.02 mmol/l, −32.6% and 1.39 vs. 2.02 mmol/l, −31.2%, respectively; (c) TG −0.73 vs. 0.88 mmol/l, and 0.75 vs. 0.88 mmol/l; −17 and −14.8%, respectively, and TC in liver (17.1 vs. 24.3 μmol/g, −29.6% and 17.9 v. 24.3 μmol/g, −26.3%, respectively. Sugar beet and apple pomace fiber-supplemented diets significantly hindered the decrease in HDL-PH (0.79 vs. 0.63 mmol/l, −25.3%, P<0.025 and 0.75 vs. 0.63 mmol/l, −19%, P<0.05, respectively) and decreased the level of TPH (1.34 vs. 1.74 mmol/l, −23%, P<0.005 and 1.37 vs. 1.74 mmol/l, −21.3%, P<0.01, respectively). Both sugar beet pulp fiber and apple pomace fiber, in rats fed the basal diet without cholesterol, did not significantly affect the variables measured. Neither sugar beet pulp fiber or apple pomace fiber-supplemented diets influenced the level of lipid peroxides. These results demonstrate that sugar beet pulp fiber and to a lesser degree apple pomace fiber possess hypolipidemic properties. This is more evident when sugar beet pulp fiber or apple pomace fiber are added to the diet of rats fed cholesterol. The hypolipidemic effects of both sugar beet pulp fiber and apple pomace fiber can be attributed to their water-soluble parts. The sugar beet pulp and apple pomace fibers have no antioxidant properties.     

The correlation between serum total cholesterol and some trace elements in serum,liver and heart of rats fed high cholesterol diet

The work indicates the link between the serum cholesterol, atherosclerosis and certain metal metabolism. 122 adult albino rats were used in this study and classified into 5 groups: Control group, 29 rats fed the stock diet; group I, 32 rats fed the stock diet with 1 % cholesterol for 6 weeks; group II, 36 rats fed the stock diet with 1 % cholesterol for 8 weeks; group III_A, 17 rats fed the stock diet and 0.2 ml oil/day orally for 8 weeks and group III_B, 18 rats fed the stock diet and 0.2 ml oil with cholesterol daily (50 mg cholesterol/1 ml oil) for 8 weeks. The results obtained showed that: 1. A positive correlation was found between serum total cholesterol and serum copper, cadmium and Cd/Zn ratio, whereas a negative correlation occurred between serum total cholesterol and serum Zinc and Zn/Cu ratio. 2. A positive correlation was found between serum total cholesterol and cadmium, Zn/Cu and Cd/Zn ratio in liver. On the other hand, a negative correlation occurred between serum total cholesterol and copper in liver. 3. A positive correlation was found between serum total cholesterol and Zn/Cu ratio in heart which was negative in heart copper, cadmium and Cd/Zn ratio. Histopathological examination of liver sections of animals treated with cholesterol revealed the presence of mild degree of fatty change, while the kidney tissues showed glomerular lesion in the form of obliteration of Bowman's capsule with increased cellularity inside, beside degenerated tubules and interstitial fibrosis.     

Induction of oral tolerance, in mice, to gum arabic

As part of a programme of research on the immunological properties of the exudate gums, the capacity of gum arabic to induce immunologic hyporesponsiveness when fed (oral tolerance) has been examined. Inbred mice were fed saline or gum arabic; 1 week later all were systemically immunized with the antigen emulsified in complete Freund's adjuvant. Mice which had been fed the antigen had significant suppression of the humoral (P less than 0.01) and cell mediated (P less than 0.01) immune responses to the antigen. These results demonstrate that although gum arabic is a complex, proteinaceous polysaccharide antigen, it is tolerogenic when an animal encounters it by the natural route, via the gut.     

The correlation between serum total cholesterol and some trace elements in serum, liver and heart of rats fed high cholesterol diet.

The work indicates the link between the serum cholesterol, atherosclerosis and certain metal metabolism. 122 adult albino rats were used in this study and classified into 5 groups: Control group, 29 rats fed the stock diet; group I, 32 rats fed the stock diet with 1% cholesterol for 6 weeks; group II, 36 rats fed the stock diet with 1% cholesterol for 8 weeks; group IIIA, 17 rats fed the stock diet and 0.2 ml oil/day orally for 8 weeks and group IIIB, 18 rats fed the stock diet and 0.2 ml oil with cholesterol daily (50 mg cholesterol/1 ml oil) for 8 weeks. The results obtained showed that: 1. A positive correlation was found between serum total cholesterol and serum copper, cadmium and Cd/Zn ratio, whereas a negative correlation occurred between serum total cholesterol and serum Zinc and Zn/Cu ratio. 2. A positive correlation was found between serum total cholesterol and cadmium, Zn/Cu and Cd/Zn ratio in liver. On the other hand, a negative correlation occurred between serum total cholesterol and copper in liver. 3. A positive correlation was found between serum total cholesterol and Zn/Cu ratio in heart which was negative in heart copper, cadmium and Cd/Zn ratio. Histopathological examination of liver sections of animals treated with cholesterol revealed the presence of mild degree of fatty change, while the kidney tissues showed glomerular lesion in the form of obliteration of Bowman's capsule with increased cellularity inside, beside degenerated tubules and interstitial fibrosis.     

Determination of the calorific value of gum arabic in rats using modified versions of the growth bioassay and the digestibility assay

The calorific values of gum arabic (GA), cellulose (Solka Floc) and sucrose were measured in a rat model using modifications to the growth assay and energy balance procedures simultaneously. Although the two procedures gave consistent results for cellulose (Solka Floc) and sucrose, i.e. 0 and >3.5 kcal g⁻¹, respectively, contradictory results were obtained for GA. The growth assay procedure indicated that GA had zero calorific value while the energy balance procedure indicated a value of 3.1 kcal g⁻¹. Similar results have been reported by other researchers using the two different techniques separately. Results of this type have led to confusion as to the actual calorific value of GA. The anomalous results for GA may be explained in terms of losses resulting from processes which provide no calories for the rat, for example bacterial fermentations in the caecum. Other sources of loss may also have a role. We have proposed that the calorific value of zero as determined using the growth assay is the correct value in the context of the nutritive value of GA.     

Decrease in serum total cholesterol and increase in high‐density lipoprotein cholesterol in rats following moderate intake of sherry

Moderate intake of sherry by rats resulted in a decrease in serum total cholesterol and an increase in the proportion of high‐density lipoprotein cholesterol. Oloroso, manzanilla, fino and amontillado sherries all exerted similar effects. These effects were apparently not related to the ethanol content, since an aqueous solution of ethanol did not modify cholesterol levels. Therefore other compounds must be responsible for the effects observed. This paper shows that, in addition to typical red and white wines, sherries should be included in the list of wines with beneficial physiological effects following moderate consumption. Copyright © 2004 Society of Chemical Industry     

Dietary effects on growth,liver peroxides,and serum and lipoprotein lipids in rats fed a thermoxidised and polymerised sunflower oil

The effect on food intake, weight gain, liver lipid peroxides, lipemia and lipoprotein composition was determined in rats fed a diet with 15% sunflower oil used repeatedly for frying and containing ∽19% polar material (group 2). These dietary effects were compared over a 4 week study period with those found in rats fed a control diet that contained 15% unused sunflower oil with ∽5% polar material (group 1). Both groups had similar food and nutrient intakes (except for linoleic acid, significantly lower (P<0·01) in group 2), yet the final weight gain and food efficiency and protein efficiency ratios were significantly lower in group 2. As a consequence of thermoxidised oil ingestion, liver homogenates from group 2 presented higher (P<0·02) levels of thiobarbituric acid reactive substances (TBARS) Liver TBARS levels were significantly correlated (P<0·01) with the amount of thermoxidised substances ingested. No treatment effect was found on VLDL lipid composition. However, the LDL fraction of group 2 animals appears enriched (P<0·05) in total and free cholesterol. In group 2 rats, phospholipids, and total and esterified cholesterol were significantly increased (P<0·05) in HDL. As a consequence of the changes in the lipoprotein composition, the amount of all forms of serum cholesterol, and serum phospholipids was significantly higher (at least P<0·05) while the amount of serum triacylglycerols remained unchanged in rats fed the used oil. HDL-phospholipids were significantly correlated (P<0·02) with the amount of thermoxidised compounds ingested. The increase in serum cholesterol and phospholipids, and in HDL-cholesterol and HDL-phospholipid concentration seens in group 2 rats may be a protective mechanism against the peroxidative stress produced by the ingestion of used sunflower oil. © 1998 SCI.     

精氨酸对夏季旱养肉鸭生长性能和免疫器官的影响

研究循环高温环境下精氨酸营养对肉鸭生长性能和免疫器官的影响。选择90只出壳健康商品樱桃谷肉鸭,随机分为3组,分别饲喂添加0%、0.5%和1.0%L-精氨酸的饲粮。结果显示:添加0.5%L-精氨酸可显著降低肉鸭生长全期(0～49日龄)的料重比(P<0.05),并可显著提高21日龄肉鸭肝脏指数和49日龄肝脏粗蛋白质的含量(P<0.05)。     

Increased concentrations of liver cholesterol in rats fed lactulose

The disaccharide lactulose (beta-D-galactopyranosyl-(1-4)-D-fructofuranose) is thought to be poorly hydrolized by intestinal enzymes but is broken down by microorganisms in the colon. Thus lactulose shares with pectin similar characteristics. Lactulose is used in the food industry and in the treatment of constipation. There is preliminary evidence that dietary lactulose (5%, w/w) causes increased concentrations of serum and liver cholesterol in rats when compared with pectin. This paper describes dose-response relationships between dietary lactulose and cholesterol in either serum or liver.     

Effects of guar gum and arabic gum on the physicochemical,sensory and flow behaviour characteristics of frozen yoghurt

This study investigated the effect of guar gum and arabic gum on physicochemical, sensory and flow behaviour properties of frozen yoghurt. The results indicated that gums significantly affected the viscosity, overrun and melting rate of frozen yoghurt. The highest overrun value was observed in sample containing 0.5% arabic gum. Frozen yoghurt containing 0.3% guar gum had the highest viscosity. The longest first dripping time was observed in sample containing 0.5% arabic gum. Flow behaviour of samples showed that all frozen yoghurts exhibited shear thinning behaviour. Guar gum at a concentration of 0.2% and arabic gum at a concentration of 0.5% presented the best total acceptability. The results of this study revealed that the frozen yoghurt produced with arabic gum had the better overall sensory and physicochemical characteristics.     

Characterisation of interactions between fish gelatin and gum arabic in aqueous solutions

The interactions between fish gelatin (FG) and gum arabic (GA) in aqueous solutions were investigated by turbidimetry, methylene blue spectrophotometry, zeta potentiometry, dynamic light scattering, protein assay, and state diagram at 40 °C and a total biopolymer concentration (C(T)) of 0.05%. FG underwent complex coacervation with GA, possibly via its conformational change, depending on pH and FG to GA ratio (FG:GA). The formation of FG-GA complexes was the most intense when pH 3.55 and FG:GA=50:50 (6.6:1 M ratio), however, the coacervate phase was found to be composed of a much higher FG fraction. The pH range of complex formation shifted to a higher pH region with increasing FG:GA. Soluble and insoluble FG-GA complexes were formed even in a pH region where both biopolymers were net-negatively charged. Varying C(T) significantly influenced not only the formation of FG-GA complexes but also the development and composition of coacervate phase.     

Effects of dietary calcium, vitamin D3, and corn supplementation on growth performance and mineral metabolism in young goats fed whole milk diets

Twenty-four male goats, approximately 2 to 4 wk of age, were allotted to four dietary treatments in a 2 X 2 factorial design and were fed a basal milk diet at 12.5% body weight for 20 wk. Vitamin D3 was added to the milk in two different amounts with and without supplemental CaCO3. At the end of wk 7, corn was added to all diets at 1% body weight. Over 20 wk, average daily gain was unaltered by addition of Ca or vitamin D3 to the diet. When corn was added to the diet, gains increased from 48 to 180 g/d. Plasma Ca concentrations were not affected by dietary treatment. Supplemental Ca decreased plasma Mg concentrations. Corn supplementation curtailed a depression in plasma Mg and seemed to prevent a whole milk-induced hypomagnesemia. Fecal excretion of all minerals measured was increased in goats fed supplemental Ca. Dietary Ca increased urinary Ca but decreased urinary Mg. Percentage of apparent absorption of Ca, Mg, and total ash was lower in Ca-supplemented goats, as was apparent retention of Ca and Mg. The physiological responses reported suggest the goat as a potential research model for mineral metabolism studies in other ruminants.     

A review of recent developments on the regulatory, structural and functional aspects of gum arabic

There have been substantial developments recently concerning the regulatory aspects of gum arable and the elucidation of its structure and functional characteristics. The aim of this paper is to present the position with regard to its current legal definition, to summarize what is now known about the structure of this complex polysaccharide and to illustrate how the structural features relate to its functional properties, notably its ability to stabilize oil-in-water emulsions and to form concentrated solutions of low viscosity.     

卡拉胶和阿拉伯胶的复配及其在低温火腿中的应用研究

旨在对卡拉胶和阿拉伯胶复配进行了研究,当卡拉胶:阿拉伯胶=3:2混合、总量为0.5%加入火腿类产品中,产品质构有明显提升,工业生产中值得推广应用.     

Potentiation of the hypolipidemic influence of dietary tender cluster bean (Cyamopsis tetragonoloba) by garlic in cholesterol fed rats

Tender cluster bean (Cyamopsis tetragonoloba) (CB), a rich source of soluble fibre was evaluated for hypolipidemic influence in atherogenic situation along with a known hypocholesterolemic spice garlic in rats. Wistar rats were rendered hypercholesterolemic by feeding 0.5% cholesterol diet for 8 weeks. Inclusion of CB (15%), garlic (1%) and their combination in high-cholesterol diet produced significant hypolipidemic effects. The combination produced 56% decrease in serum cholesterol. Decrease in serum cholesterol seen in basal groups by these dietary interventions was additive with the combination. Increase in serum triglycerides was countered in animals fed CB, garlic or their combination. Elevation in hepatic cholesterol and triglycerides was countered by CB and garlic, the combination reducing it even more. Biliary secretion of bile acids was increased by CB, garlic and their combination in atherogenic condition. Thus, garlic potentiated the beneficial influence of dietary CB on serum, liver and biliary lipids in high-cholesterol fed situation.     

Effect of various dietary fats and proteins on serum cholesterol level in rats

A 60 day experiment on growing rats was performed to evaluate the effect of two protein sources (casein and soybean protein isolate) and four fats (olive oil, OO; evening primrose oil, EO; linseed oil, LO; and butter, B) on plasma lipoprotein fractions: total cholesterol (TC), high‐density lipoprotein cholesterol (HDL‐C), low‐density lipoprotein cholesterol (LDL‐C) and triacylglycerol (TAG) levels. The different protein and fat sources had no influence on body weight gain of rats. Fats had no significant effect on TC and LDL‐C. Significant differences were found only in HDL‐C. OO gave the lowest (43.3 mg dl^?1) and EO the highest (54.4 mg dl^?1) value. Proteins had a significant influence on all lipids analysed. Soybean protein caused higher TC (78.5 vs 67.9 mg dl^?1), HDL‐C and TAG levels but significantly lowered LDL‐C in the plasma of rats. These results suggest that protein has a stronger effect on cholesterol level than fat. © 2002 Society of Chemical Industry     

Increased concentrations of liver cholesterol in rats fed lactulose (Short communication)

The disaccharide lactulose (β-D-galactopyranosyl-(1-4)-D-fructofuranose) is thought to be poorly hydrolized by intestinal enzymes but is broken down by microorganisms in the colon. Thus lactulose shares with pectin similar characteristics [1]. Lactulose is used in the food industry and in the treatment of constipation. There is preliminary evidence that dietary lactulose (5%, w/w) causes increased cocentrations of serum and her cholesterol in rats when compared with pectin [2]. This paper describes dose-response relationships between dietary lactulose and cholesterol in either serum or liver.     

Effects of different levels of gum arabic, low methylated pectin and xylan on in vitro digestibility of beta-lactoglobulin

Plant hydrocolloids used in the food industry to improve texture and stability of food, such as dairy products, can reduce protein digestibility and, consequently, modify the bioavailability of amino acids. We studied the in vitro hydrolysis at 37 degrees C of beta-lactoglobulin (beta-lg) in mixed dispersions containing either gum arabic or low-methylated pectin or xylan at levels of 0, 1, 10, 20, 30, and 50% weight. Proteolysis used either pepsin alone by progressive reduction of pH during proteolysis or pepsin followed by trypsin and chymotrypsin in two different dialysis bags with a molecular weight (MW) cutoff of 1000 or 8000 Da. Results showed that beta-lg was almost resistant to pepsin digestion and that the three plant hydrocolloids inhibited significantly beta-lg digestibility as determined using dialysis bag with a 1000-Da MW cutoff. Among the three polysaccharides used, xylan showed a digestibility decrease greater than that obtained with gum arabic and low-methylated pectin. On the other hand, no significant effect of polysaccharides on the in vitro beta-lg digestibility was detected using the dialysis bag with an 8000 Da MW cutoff. This mainly suggests that peptides with MW in the range 1000 to 8000 Da may interact with polysaccharides more than peptides and proteins with a greater molecular weight to decrease the protein digestibility, and that the nature of the polysaccharides plays a role in the interaction.