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Abstract The food industry is facing the remarkable challenge of developing new food products with special health enhancing characteristics. Recently, the importance of dietary fiber in the diet has been extensively investigated . Dietary fiber promoted several beneficial metabolic and physiological effects in human. br Therefore, the present study was carried out to choose same plant sources rich in dietary fiber i.e. Pumpkin , Cauliflower , Doum and psyllium husks and used them in diets . The physicochemical and functional properties of this plant sources rich in dietary fiber were also determined . The functional properties was also determined . FTIR and thermal properties for this dietary fiber as well as studying the physiological effects of the dietary fiber on the histopathological alterations induced in colon , aorta , heart and brain were also investigated . br The results obtained -#102;-#114;-#111;-#109; the present study could be summarized as follows: br 5.1. Physicochemical properties of tested samples . br 5.1.1. Chemical composition of pumpkin , cauliflower , doum and psyllium husks powders . br The investigated samples contain high levels of carbohydrate being 94.94 , 89.85 , 81.18 and 69.75 for Ps , D , Pk and Cf , respectively. Crude fiber of these plants ranged between 6.7% in Ps as a minimum percentage and to 16.1% in Pk as maximum, -#119;-#104;-#101;-#114;-#101;as both C and D contained 11.44 and 13.62 % , respectively . On the other hand , the same samples had either very low levels of fat being 0.01 and 0.43 % for Ps and D , respectively , or relatively higher fat levels being 2.03 and 4.09 for Pk and , Cf , respectively . Cauliflower could be considered as an important vegetable source of protein being 21.72% in dry matter . br 5.1.2. Fiber analysis of pumpkin , cauliflower , doum and psyllium husks powders . br The total dietary fiber (TDF) of the studied samples (Pk , Cf , D and Ps ) were significantly different , it varied between 24.6 (Pk) and 80.9% (Ps ) -#119;-#104;-#101;-#114;-#101;as Cf and D had about 35 and 39% TDF , respectively . The highest ratio of soluble fraction in the 4 aforementioned items was found in Ps reached to about 98.6% . The other 3 DF sources contained about 83.2 , 50.0 and 68.1% soluble fractions. The insoluble DF fractions constitute about 16.8, 50.0, 31.9 and 1.4% -#102;-#114;-#111;-#109; TDF for Pk , Cf , D and Ps , respectively . As regard to the three dietary fiber fractions celluloses , hemicelluloses and lignin, they constitute about 66.4 , 0.5 and 14.5% -#102;-#114;-#111;-#109; TDF in Pk ; 46.6 , 3.6 and 2.8% in Cf as well as 35.4 , 17.5 and 28.1% in D ; 7.3 , 54.7 and 0.5 % in Ps, respectively. br 5.1.3. Mineral composition. br Eight minerals in the 4 plant specimens Pk , Cf , D and Ps were determined . These minerals were Ca , K , Mg , Na , Mn , Fe , Cu and Zn . The three principal minerals in Cf were K , Fe and Na ; in Pk : K ,Ca and Fe ; in D :K , Fe and Mg ; -#119;-#104;-#101;-#114;-#101;as in Ps :K , Fe and Ca . All plants used in the present investigation as a source of dietary fibers contained relatively large amounts of both K (247-606 mg/100 g DMB) and Fe (79-116 mg/100 g DMB) . However Na (in Cf ) , Ca( in Pk and Ps ) and Mg (in D) were also found in relatively large quantities. br 5.2. Physical properties br 5.2.1. Particle Size and degree of fineness br The corresponding highest ratio of particle fractions of Cf sample were 25.02% and 24.82 % on the sieve -lt;160 µm and 400 µm, respectively . While the highest particle size fractions was -#102;-#114;-#111;-#109; D , it was 42.18% on sieve 160 µm -#119;-#104;-#101;-#114;-#101;as Ps had 38.61% on sieve 400 µm, respectively . In the contrary , data showed that little meshing values in D , Cf , Ps and Pk were 4.83% , 5.28% , 5.43% and 6.29% on the sieve -gt;500µm , respectively . While particle size distribution on sieve -lt;160 µm of Pk , Cf and D were ranged between 22-25% except Ps which had 6.49% at the same sieve . br With regard to the modulus of fineness the following descending -#111;-#114;-#100;-#101;-#114;ed for the tested samples; Ps , Cf , Pk and D were 2.65 , 2.01 , 1.97 and 1.69 , respectively . while when the modules of uniformity was considered , the data showed difference within the two samples . The ratio of the coarse , medium and fine particles was (3:2:5) in cauliflower and pumpkin . While there is great difference between doum and psyllium husks that were (2:1:7) and (4:3:3) , respectively . br 5.2.2. Density of the tested sample br A decrease in Pk , Cf and D particle size was associated with an increase in their density . br 5.2.3. Water holding capacity (WHC) br The strong effect of PS on WHC exhibited inverse relationship between PS and WHC values . WHC values of powder of different PS were between 1.22-2.08 g/g DMB in Pk ; 3.15-7.11 g/g DMB in Cf ; 1.15-1.83 g/g dry weight in D and 5.28-10.13 g/g dry weight in Ps . These results suggested that dietary fiber -#102;-#114;-#111;-#109; Ps and Cf was more able to bind and /or entrap more water than both Pk and D. br 5.2.4. Swelling capacities(SWC) br The swelling capacities of Both Pk and Ps were also significantly higher than those of Cf and D and decreased with reducing particle sizes. These high values could be related to (SDF) content of both Pk and Ps samples. br 5.2.5. Water adsorption br Data also proved that there is proportional relation between particle size and water adsorption . For instance Pk sample had 0.305 to 0.252 g H2O/g solid when particles reduced -#102;-#114;-#111;-#109; (-gt;500 to -lt;160µm) and Ps had (0.216 to 0.169 g H2O/g solid) at the same sieves. The highest water adsorption was 0.402 g H2O/g solid at particle size -gt;500 µm in D and the lowest value was 0.142 g H2O/g solid at particle size -lt;160 µm in Cf samples . br 5.2.6. Fat absorption capacity(FAC) br Fat absorption capacity (FAC) ranged -#102;-#114;-#111;-#109; 2.39 to 5.17g/g when the PS was -gt;500µm and between 2.05 to 3.17 when PS was reduced to -lt; 160 µm . br 5.2.7. Wettability br Within each of the samples ; the following results were obtained, the highest wettability was 75 S. in Ps at particle size -lt;160 µm and on the contrary the D recorded the lowest wettability (25 S. at particle size -gt;500µm ) , as general trend the decrease in particle size for there samples was associated with an increase in wettability in all sample in the range of -gt;500µm to -lt;160 µm in Pk , Cf , D and Ps br 5.2.8. Least gelation concentration (LGC) br The least gelation concentration of Pk and Ps sample was 2% and for Cf sample it was 4% , while the LGC of D sample was up to 14% . br 4.2.9. Rheological managements. br Pk , Cf , D and Ps are of Non-Newoeutonian nature . The values of viscosity indicated the presence of a noticeable variation of all tested samples at any given shear rate . For instance ; at shear rate 3.0 S-1 the apparent viscosity were 7995.0 , 3075.0 , 8302.5 and 6150.0 cp for the Pk , Cf , D and Ps at 5% concentration , respectively. br The flow behavior index (n) of all tested samples namely Pk , Cf , D and Ps at different concentrations were less than 1.0 giving a value ranged -#102;-#114;-#111;-#109; 0.1071 to 0. 4776 ; a pattern which indicating their strong Non-Newoeutonian pseudoplastic behaviur . A noticeable increase in consistency coefficient (k) was found with increasing concentration -#102;-#114;-#111;-#109; 2.5 to 7.5% . br 5.3. Instrumental analysis br 5.3.1. Assignments of functional groups by the Fourier transform Infrared Spectrum Technique of pumpkin , cauliflower , doum and psyllium husks powders . br The functional groups that namely alkanes at wave numbers 3317 , 2364 and 1107 Cm-1 were identified in Pk sample and they were noticed at 2927 and 671 Cm-1 in Cf sample ,while alkyl halides groups of Pk samples were appeared at 1242 and 617 Cm-1 and it had 1330 and 528 Cm-1 in Cf sample . On the other hand the carboxylic acid group of Pk and Cf sample were found at 3379 and 1249 Cm-1 , respectively . Amines and amides groups were found at 3344 and 1631 Cm-1 in Pk sample , while aromatics groups were observed at 1423 , 867 and 825 Cm-1 in Pk sample and they found at 1407, 871 , 821 Cm-1 in Cf sample br D and Ps samples had alkanes groups at wave numbers 2935 and 914 cm-1 in D sample and at 2927, 1651 and 667 cm-1 in Ps sample , while the carboxylic acid group were found at 3386 cm-1 in D sample , 2360 and 1041 cm-1 in Ps sample . -#119;-#104;-#101;-#114;-#101;as the ethers group of D sample were appeared at 1242 and 1114 cm-1 and it was found at 1253 cm-1 in Ps sample . The alcohol groups was found in D sample at 3560 cm-1 , -#119;-#104;-#101;-#114;-#101;as , the phenol groups was found at 3205 cm-1 in Ps sample . br 5.3.2. Differential scanning calorimetry (DSC): br Onset temperature (T0) of all the tested samples were ranged -#102;-#114;-#111;-#109; 21 and 290 ºC , while peak gelatinization temperature (Tp) was highest (319 ºC) in D sample followed by Cf sample (310 ºC) , while, the least one (67 ºC) was observed in the peak 1 in Ps sample . The conclusion temperature (Tc) of all tested samples ranged between 102 to 350 ºC and exhibited little variation between samples , -#119;-#104;-#101;-#114;-#101;as the gelatinization temperature(R) of the tested samples were ranged -#102;-#114;-#111;-#109; 33 to 95 ºC . ΔH value of gelatinization of Ps sample was highest (228.75 mcal/mg) and lowest (5.45 mcal/mg) in the peak 3 and peak 2 as recorded in their chart , respectively . br 5.3.3. Thermogravimetric Analysis (TGA) br The thermogravimetric curves of the D , Cf and Pk samples presented the first event of the thermal decomposition in temperature intervals of 42.67 , 48.03 and 49.05 ºC, respectively, while the Ps gave highest temperature at 234.50 ºC . The percent weight loss in the first stage in the tested samples , ranged -#102;-#114;-#111;-#109; 3.192 to 6.958 % . The Pk sample recorded two stages at 207 and 429 ºC with loss of 30% , while Cf sample recorded weight losses being 24.8 , 27.5 and 34.1% at the final three stages , respectively. br 5.4. . Breadmaking quality of the tested wheat flour supplemented with pumpkin , cauliflower , doum and psyllium husks powders samples at different level. br 5.4.1. Alveograph characteristics br The alveograph characteristics of the tested samples , that maximum over pressure (P) , a measure of dough elasticity, varied -#102;-#114;-#111;-#109; 200 to 41 (mmH2O) . The average of abscissa at rupture (L) , which is a measure of dough extensibility , ranged -#102;-#114;-#111;-#109; 11 to 72 mm . On the other hand , “L” gives information about dough extensibility , longer “L” values indicating weak dough . A high P and a short L values would denote very elastic dough . Also alveograph parameters showed that flour sample contained 7.5% Ps had the highest P/L value being 18.2 at 7.5 % supplementation level , while flour sample supplemented with 2.5 % Pk was the least one (1.36) . br 5.4.2. Mixolab br Mixolab curve is separated to five different stages . The first called development stage (C1) . The dough development values of the tested wheat flour samples supplemented by different levels of plant powders were ranged -#102;-#114;-#111;-#109; 1.01 to 1.16 Nm and the maximum torque reached during mixing in this stage at 30 ºC was appeared in flour samples supplemented by 10 % P sample followed by 5 , 7.5 % in Pk and 7.5 % D . The dough stability during heating of the control sample was 10.82 min , while sample supplemented by 10% D had 11.47 min followed by Ps sample of the same added level as it was 11.45 min and the lowest value of 6.03 min was found in Cf sample at the same level . However , in the second stage (C2) , protein reduction was 0.79 Nm in Ps at a level of 10 % compared to control sample (0. 51 Nm) followed by Ps at 7.5% (0.79 Nm) , while the torque values of protein reduction were as low as 0.31 and 0.35 Nm in Cf at 7.5 and 10 % , respectively . At the third stage (C3) , the highest value (2.01 Nm) was found in sample supplemented by 10% D and the lowest value (1.33 Nm) was observed in Ps at 10% supplementation . The temperatures associated to the starch gelatinization as pasting temperature range in this stage was 73.0- 86.2ºC for all tested samples . However at the fourth stage (C4) , the minimum torque reached during cooling to 50 ºC was 0.69 Nm of wheat flour sample supplemented by Ps at 10 % level and the highest value 1.92 Nm was observed at the same level in samples supplemented with D . On the other hand the torque values in P and Cf were ranged between 1.77 to 1.86 Nm and 1.36 to 1.57 Nm , respectively. During the fifth stage (C5), the highest value of torque produced after cooling at 50 ºC of starch gelling reached 3.15 Nm in D at 10 % supplementation level and the lowest value (1.02 Nm) was found in Ps at the same level . br 5.4.3. processing of pan bread . br The bread loaf volume was much better for all tested samples after 60 min fermentation time . However , sample with 2.5% Ps and that of control appeared almost to have statistically the same volume being 920 and 900 , respectively , compared to other flour samples under study. Weight of loaves -#102;-#114;-#111;-#109; tested flour samples was almost constant and ranged -#102;-#114;-#111;-#109; 240 to 265 g for all tested samples . Additionally , bread baked -#102;-#114;-#111;-#109; flour contained 2.5% Pk was of higher specific volumes reached 4.1 ml/g . In contrast , Cf at 10% sample showed the lowest specific volume (2.3 ml/g) . On the other hand sample with 10 % Cf had high density (0.44 g/ml) while loaves supplemented with 2.5% Pk recorded the lowest value (0.24 g/ml) and all tested sample ranged between 0.27-0.33 g/ml . The moisture content in pan bread ranged -#102;-#114;-#111;-#109; 39.56 and 27 % . The Ps samples records the high percent of moisture content as it was 39.6 , 37.6 , 36.7 and 34.9 and at Ps 10 , 7.5 , 5 and 2.5 % , respectively . br 5.4.4. Sensory evaluation br Mean sensory scores of volume showed significant differences (P ≤ 0.05) between the tested samples. -#119;-#104;-#101;-#114;-#101;as Ps sample at 7.5 % had the highest score value (13.3) followed by Pk and Cf samples at 2.5(13.2 and 13.0 , respectively ) , while control sample was 12.70 and the lowest score of volume 7.6 was recorded for the pan bread baked wheat flour supplemented with 10 % Cf powder . The crust color of breads changed -#102;-#114;-#111;-#109; light brown to dull brown . The best color typical for pan bread was bright to golden brown which observed in Ps , Pk , and Cf at 2.5 % supplemented samples compared to other tested samples and their recorded scores were 4.7 , 4.7 and 4.8 , respectively , while the color score of bread processed -#102;-#114;-#111;-#109; control sample was only 4.2 . On the other hand , the desired textural quality characteristics in pan bread with added Cf at 2.5 % and Ps at 7.5 % were greater in pliability and obtaining soft texture ; maximum scores were observed as 18.1 and 17.9 , respectively , followed by control , Pk and D at 2.5% level added to manufactured flour . Minimum score 9.6 was recorded for bread which had 10 % Cf . Control bread had strong flavor (13.6) of the crumb compared to other tested samples , followed by Ps , D and Pk at 2.5% ( ranged between 13 and 13.1) . Additionally, Cf at 7.5 and 10 % breads had weaker flavor they received 4 and 3.5 score values , respectively , compared to other tested samples . In addition control and D at 2.5 % breads did not differ significantly (P ≤ 0.05) for graininess . The scores of control was 16.6 followed by the Ps and D at 2.5 % (15.6) and Pk at 2.5 % (14.4) -#119;-#104;-#101;-#114;-#101;as the Cf at 10 % had the least score , being 9.5 . The maximum score of symmetry for Cf and D at 2.5 % level was 5.9 followed by control (5.8) and Ps at 7.5% (5.7) . Addition of Cf at 7.5 and 10% greatly reduced symmetry score to be only 3.3 and 3.5 , respectively . In the same time the minimum score was observed of break- shred in pan bread samples with added Cf at 10 % level . Control and pan bread with added Cf at 2.5 % had the maximum scores of break - shred , followed by Ps at 7.5% . br The overall acceptability of tested breads were ranged -#102;-#114;-#111;-#109; 42.96 to 83.4% . The maximum score of the overall acceptability was observed in the control , then bread supplemented by 2.5% added powders in all tested samples . -#119;-#104;-#101;-#114;-#101;as samples with added the Cf at 7.5% and 10 % showed overall acceptability gained scores of only 48.4 and 42.96, respectively -#119;-#104;-#101;-#114;-#101;as Pk at 10 % level shows overall acceptability of 49.8. br 4.5. Biological Evaluation of the pumpkin , cauliflower , doum and psyllium husks powders when added to experimental animal diets . br 4.5.1. Food consumption: br Among the experimental groups , however , no substantial differences of food consumption were observed. Furthermore, food consumption did not significantly alter with age (i.e 68and 98 days). The animals fed on diets containing Ps at levels of 10 and 20% followed by those fed on diets containing the D at the same both levels produced larger fecal weight . In cantrast , smaller fecal weights were observed for the positive control animals and for group which their diets contained 10% Pk . br 4.5.2. Body weight br Significant gradual increase in body weight of albino rats fed on different diets was continued with different rates depend on rats diet during the whole experiment up to 60 days. br 4.5.3. Organs weight of rats subjected to feeding on different diets. br The heart weight ranged between 0.5 and 1.0 gm after 30 and 60 days . Only the hearts of rats fed on the control negative diets (without added C to normal diets) and rats fed on diets with added Ps weighed significantly less than the other groups . The remaining 7 treatments were either did not show any significant weight change (groups 2 and 5) or suffered a weight loss between 11.11 - 30% . Brain weight loss after 60 days , being -16.67 , -8.33 and -25% for groups fed on diets contained 20% Cf ,20 % D and 20 % Ps,were shown . br 4.5.4. Blood lipids profile br Addition of Ps to the hypercholesteremic diets was the most effective in reducing cholesterol (C) formation in blood. D powder addition to the rat diets also was very effective in reducing the rate of C formation in the blood . It is worthy mentioning that , examining the C levels of groups 3,4,5 and 6 contained Pk and Cf powders showed a long action effect of dietary fibers on these levels which decreased after 60 days compared to their levels after 30 days. br Supplementation C rich diets (1% C+0.2% cholic acid) with dietary fiber sources (Pk , Cf , D and Ps ) showed reduced rates of total and LDL-cholesterol and total lipids formations compared to hypercholesterolemic group. High density lipoprotein (HDL) was high in rats serum fed on diets supplemented with dietary fiber . br Very high atherogenic indices were obvious in rat’s group fed on the cholesterol –rich diet being 9.63 and 9.86 after 30 and 60 days , respectively . Far below levels were found in either the negative control group (1) or the remaining 8 groups fed on diets supplemented with sources (Pk , Cf , D and Ps) rich in dietary fibers ( at levels of 10and 20%). br 4.5.5. Histopathological alterations br 4.5.5.1. Colon br Description of histopathological alterations induced in colon of rats fed different rich-sources of dietary fiber was investigated in details. br Normal histological structure of the mucosal layer (mu) and muscularis (ml) as well as submucosa(sm)and senosa(s) were observed in control negative . Groups 2 , 3 , 5 , 6 , 7 , 9 and 10 subjected to hypercholesterolemic diet supplemented with rich –sources of dietary fibers (Pk , Cf , D and Ps at 10 and 20 % levels) show focal lymphoid cell aggregation in the mucosal layer (m) and few inflammatory cells infiltration in the submucosal layer(m) . In contrast , groups(4) supplemented with 20% Pk and (8) supplemented with 20% D did not show any histopathological alterations , i.e such level (20%) of dietary fibers -#102;-#114;-#111;-#109; Pk and D prevented any pathological changes induced in colon hypercholesterolemic rats . br 4.5.5.2. Aorta br The control rat group fed on the control diets and subjected to examination after 30 and 60 days showed no histopathological alteration; a normal histological structure of myocardium was recorded . With regard to the rats of group 2 which suffers induced hypercholesterolemia , their aorta showed diffuse vacuolization in the media after 30 and 60 days of feeding . In the rats of groups 3 , 5 , 6 , 7 and 8 there was vacuolization either mild or sever after 30 days . In contrast hypercholestremic diets supplemented with 10 or 20% Ps powder did not show histopathological alteration in rats aorta. Soluble fibers found in (Pk , Cf , D and Ps powders) have been considered and proved herein to be effective in the treatment of hypercholesterolemia. The aorta of groups 3 and 4 (Pk 10 and 20%) as well as 5 and 6 in addition to group 10 showed complete recovery and repairing . br 4.5.5.3. Heart br The experimental animal fed on the diet containing 1% C without added dietary fibers suffered myocardium focal haemorrhage as well as focal inflammatory cells infiltration (after 30 days) -#119;-#104;-#101;-#114;-#101;as after 60 days degenerative changes were also observed in the myocardium . It is of great importance to say that up to 20% of Ps powders in the diet could prevent and recover any histopathological alterations even in a short period br 4.5.5.4. Brain br Group 1 (control) showing a normal histological structure of the meninges (m) and cerebral cortex (cc) as well as hippocampus (hp) and striatum (s) . The histobathological alteration induced in the brain of hypercholesterolemic rats group 2 show plaques formation (g) with diffuse gliosis in between as well as neuronal degenerative (d) and cellular oedema (60 days) . Different less symptoms in brains of other 8 rat groups fed on two levels of DF had recorded after examinations which proved that positive effects occurred in these groups . |