Wheat bran diets

Nicolle C, Manach C, Morand C, Mazur W, Adlercreutz H, Remesy C and Scalbert A (2002), Mammalian lignan formation in rats fed a wheat bran diet , J Agric Food Chem, 50, 6222-6226. 

Experiment 2. In this experiment the basal diet, a 5% HM-pectin diet and a 10% wheat bran diet (corresponding to 5% bran fiber) were fed to groups of 7 rats both with and without 0.5% dietary cholesterol. For comparison, 10% wheat bran and 10% oat bran diets were also studied (without cholesterol). 

The diet treatments were level of phytate intake, either 0.2 or 2.0 g/day. Each level was consumed for 15 days, three consecutive repeats of the 5-day menu cycle. To provide 2.0 g/day of phytic acid, 36 g of wheat bran was baked into 6 muffins and two muffins were eaten each meal. Dephytinized bran was prepared by incubating the bran in water and allowing the endogenous phytase to hydrolyze the phytate, then the entire incubation mixture was freeze-dried (4) and 36 g baked into 6 muffins. Thus, the intake of all nutrients and neutral detergent fiber was the same for both phytate intakes. Five subjects consumed the whole bran muffins for 15 days followed by the dephytinized bran muffins for 15 days and the other 5 subjects in the reverse order. Brilliant blue dye was given at breakfast on the first day of each collection period to aid in demarcation of stools. Stool composites were made for days 1-5, 6-15, 16-20 and 21-30 and urine composites for days 6-15, and 21-30. Daily food composites were made, homogenized, freeze-dried and then analyzed to determine mineral nutrient intakes. 

The wheat bran used in these studies was milled for us from a single lot of Waldron hard red spring wheat. Other foods and diet ingredients were purchased from local food suppliers. Data from HS-I was analyzed statistically by Student s paired t test, each subject acting as his own control. A three-way analysis of variance (ANOVA) was performed to test for significant differences betwen diet treatments, periods and individuals in HS-II and HS-III. 

Addition of bran from hard red and soft white wheat bran, psyllium fiber, and cellulose resulted in increased losses of calcium in feces in comparison to losses when no fiber supplements were used (P<0.05). Urinary calcium losses were not significantly affected however, calcium balances were lowered when these four fiber sources were added to the laboratory controlled diet (P < 0.05). 

Diet Codes rwb = red wheat bran wwb = white wheat bran cb = corn bran rb = rice bran pf = psyllium fiber p = pectin c cellulose... 

Utilization of iron was not affected at levels of 9 to 26g bran/day from corn or wheat (19, 2J0 2 ) or bY 16 g of bran/day (25). Negative balances were observed by Morris and Ellis (21) during the first balance period with daily intakes of 36g bran but not during the second 5-day balance period. However, Simpson et al. (24) found a marked inhibition of non-heme iron absorption from a single test meal which included 6 g of wheat bran. With a diet which provided 35g/day of NDF (neutral detergent fiber from bran bread), iron balances were decreased (26) compared to the 9 or 22g/day intake levels. 

Five differenf combinations of psyllium and wheat bran, with comparative levels of wheaf bran fo psyllium of 12% and 0%, 8% and 2%, 6% and 3%, 4% and 4%, and 0% and 6%, were evaluated and compared for fheir effects on chemically induced mammary tumorigenesis in F344 rats (Cohen et ah, 1996). After 19 weeks on the treatment diets, rats on 1 1 (wheat bran/psyllium) had the lowest rate of mammary tumorigenesis, and rats on the other combined fiber diets or on the psyllium-alone diet had an intermediate rate of fumorigenesis. Rats on a diet with higher level... 

Clark, C. A., Gardiner, J., McBurney, M. 1., Anderson, S., Weatherspoon, L. J., Henry, D. N., and Hord, N. G. (2006). Effects of breakfast meal composition on second meal metabolic responses in adults with type 2 diabetes mellitus. Eur. J. Clin. Nutr. 60,1122-1129. Cohen, L. A., Zhao, Z., Zang, E. A., Wyrm, T. T., Simi, B., and Rivenson, A. (1996). Wheat bran and psyllium diets Effects on N-methylnitrosourea-induced mammary tumorigenesis in F344 rats. /. Natl. Cancer Inst. 88, 899-907. 

Jackson, K. A., D. A. I. Suter, and D. L. Topping. Oat bran, barley and malted barley lower plasma cholesterol relative to wheat bran but differ in their effects on liver cholesterol in rats fed diet with and without cholesterol. 

Carcinogenesis inhibition. Polysaccharide fraction of the dried seed hulls, administered to rats by gastric intubation, was active vs tumor induction with N-ethyl N-nitro-N nitrosoguanidine h Rice bran, administered orally to male rats at a concentration of 4% of the diet, was active. A 1 1 combination of wheat bran and psyllium, at a total level of 8% dietary fiber, offers the highest protection against colon tumor development . 

PO013 Cohen, L. A., Z. Zhao, E. A. Zhang, T. T. Wynn, B. Simi, and A. Rivenson. Wheat bran and psyllium diets effects on N-methylnitrosourea-induced mammary tumorigenesis in F344 rats. J Nat Cancer Inst 1996 88(13) 898-907. 

The best sources of manganese are wheat bran, dried legumes, seeds, nuts and leafy green vegetables, other good sources are cereal grains, coffee and tea. The adequate range in adult diet is 2.5 to 5.0 mg/day. 

Draganov (1986) reviewed findings on the utilization of brewers grains in poultry and livestock diets and concluded that it could be used as a partial substitute for wheat bran, soybean meal and sunflower seed meal in poultry diets, e.g. at levels up to 200g/kg in broiler diets. More recent research, however, has indicated that dried brewers grains caused a reduction in feed intake when included in broiler diets at more than lOOg/kg (Onifade and Babatunde, 1998). Results with laying hens indicated a reduction in body... 

The mechanism by which this reduction in availability occurs was recently evaluated (9). Chicks were fed 2000 ppm Mn for 14 days and then placed on diets containing 14 ppm Mn with or without 10% wheat bran supplementation. Chicks were killed serially for two weeks following the period of Mn "loading". Tissue Mn levels decreased with time, but wheat bran did not affect rate of tissue Mn depletion. Thus, wheat bran did not affect homeostasis of stored Mn. In another experiment (9), 10% dietary wheat bran was fed to chicks receiving varying amounts of inorganic Mn administered via intraperitoneal injection. 

In a series of studies ranging from 14 to 56 days each, adult human subjects were fed constant, measured, laboratory controlled diets. Diets were based on ordinary foods and included the following items milk, unenriched 70% flour bread (plus wheat bran in some studies), ready-to-eat oat or corn based breakfast cereals, green beans, tomato and orange juice (or apple juice in some studies), peanut butter, ground beef and tuna (or soy isolate products), peaches,... 

As shown on Table III, the subjects fed 20 g of hemicellulose from purified psyllium fiber excreted significantly more manganese in the feces than when they were fed bread without the hemicellulose supplement. Unlike wheat bran, purified psyllium fiber (sold commercially as a bulk laxative) contains no manganese or phytates hence, any change in fecal manganese excretion when psyllium fiber is added to human diets can probably be credited to the mixture of hemicellulose comprising this product. 

The effect on zinc balance of a 10-fold difference in dietary molar ratio of phytate/zinc was tested in a metabolic balance study with 10 adult men. The mean zinc balance was 2.7 mg per day vrtien the dietary molar ratio of phytate/zinc was about 12 and 2.0 mg per day when the ratio was about 1. Menus consisted of foods commonly consumed in the United States. The mean daily intake of zinc was 17 mg and of neutral detergent fiber 16 g. The molar ratios of phytate/zinc were attained by using 36 g per day of whole or dephytinized wheat bran. Analysis of hospital and self-chosen diets Indicate that the majority of the United States population consume diets with molar ratios of phytate/zinc less than 10, but which provide less than the recommended dietary allowance of zinc. The balance results are discussed in relation to magnitude of the zinc intake, the type of food consumed and the role of adaptive responses in maintaining adequate zinc nutriture. 

Many experiments have demonstrated the capacity of cellulases and of mixtures of cellulases, pectinases, and hemicellulases to break down or to soften plant cell walls. For human diets this would be beneficial in preparing infant or geriatric foods where reduced fiber content is desired. Recently treatment of wheat bran was found to increase the in vitro protein digestibility by 35% (63) and to increase weight gain of rats fed a bran-containing ration. The aleurone cell wall was the primary substrate for these enzymes. 

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