Phytase wheat

As discussed above, wheat has been used only rarely for molecular farming. Thus far, the only example of a pharmaceutical protein produced in wheat is a single chain Fv antibody, which was expressed using the Ubil promoter and achieved a maximum expression level of 1.5 pg g 1 dry weight [77]. Transgenic wheat producing Aspergillus phytase has also been reported [78]. 

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. 

Bioavailability of nutrients may be influenced beneficially or adversely by pelleting. For example, the availability of phytate phosphorus in grains was found to be increased by steam-pelleting (Bayley et al., 1975). On the other hand, there may be destruction of heat-labile nutrients and components, such as phytase enzyme in wheat or vitamin A. 

Wheat Endosperm-specific phytase expression Seed Aspergillus fumigatus PhyA (40)... 

Brearley, C.A., and Hanke, D.E., 1996b, Inositol phosphates in barley (Hordeum vulgare L.) aleurone tissue are sterochemically similar to the products of breakdown of Ins P6 in vitro by wheat bran phytase. Biochem. J. 318 279-286. 

Each meal included two-bran muffins that contained 6 g each of either whole bran or dephytinized bran (36 g of bran consumed each day). The bran was milled from a single lot of hard red spring wheat and one-half was dephytinized by action of the endogenous phytase. The mean iron intake was 18.2 mg per day, approximately one-third in the muffins. Phytic acid intakes were 2.0 and 0.2 g per day, respectively, when whole bran muffins or dephytinized bran muffins were consumed, but there was no difference in neutral detergent fiber intakes, 17 g per day. 

The phytate content of California small white beans (Phaseolus vulgaris) can be greatly reduced by allowing a suspension of raw beans to autolyze (pH 5.2, 35°-55°C, 20-48 hr) or by adding a preparation of wheat germ phytase under the same conditions (47, 59). 

Rodehutscord, M. M. Faust H. Lorenz. Digestibility of phosphorus contained in soybean meal, barley, and different varieties of wheat, without and with supplemental phytase fed to pigs and additivity of digestibility in a wheat-soybean meal diet. /. Anim. Phys. Anim. Nutr. 1996, 75, 40-48. 

Activation energy values for the hydrolysis of myo-inositol hexakisphosphate and of esters with lower phosphate content were between 35.6 kJ/mol in germinated Phaseolus aureus (Mandal et al., 1972) and 50.2 kJ/mol in wheat bran (Nagai and Funahashi, 1962). The optimum temperature for the enzymatic hydrolysis of myo-inositol hexakisphosphate varies among phytases between 45 and 57°C (Nayini and Markakis, 1986), and even up to 60°C for the phytase of Bacillus subtilis (Powar and Jagannathan, 1982). 

The lowest and the highest values for myo-inositol hexakisphosphate hydrolysis were reported in phytases of Aspergillus ficuum (pH 5.3, 0.01 mM) and in that of germinated Phaseolus aureus (0.65 mM), respectively. The highest values reported were of wheat bran phytase towards myoinositol tetrakis- and trisphosphate (5 mM see Nayini and Markakis, 1986). K and K, values for the enzymatic hydrolysis of myoinositol hexakisphosphate by different Bacillus spp. were determined to be approximately 0.44 mM and 18.6/s, respectively. The affinity of myo-inositol pentakisphosphate for the phytase enzymes and their maximal rates of hydrolysis were lower (K = 0.50-0.76 mM 7.4-16/s) than that of myo-inositol hexakisphosphate (Greiner et al., 2002). 

Eim, P.E. andTate, M.E. (1 973)The phytases. III. Properties of phytase fractions F, and from wheat bran and the m/o-inositol phosphates produced by fraction F. Biochimica et Biophysica Acta 302, 315-328. 

Nagai, Y. and Funahashi, S. (1952) Phytase from wheat bran. I. Purification and substrate specificity. Agricultural and Biological Chemistry 26,... 

Richardson, A.E., Hadobas, P.A. and Hayes, J.E. (2000) Phosphomonoesterase and phytase activities of wheat (Triticum aestivum L.) roots and utilisation of organic phosphorus substrates by seedlings grown in sterile culture. Plant, Cell and Environment 23, 397 05. 

Romero J, Zydney AL (2002) Affinity ultrafiltration effects of ligand binding on selectivity and process optimization. Biotechnol Bioeng 77(3) 256-265 Roopesh K, Ramachandran S, Nampoothiri KM et al. (2006) Comparison of phytase production on wheat bran and oilcakes in solid-state fermentation by Mucor racemosus. Biores Technol 97(3) 506-511... 

Barrier-Guillot B., Casado R, Maupetit R.Jondreville C., Gatel F., 1996. Wheat phosphorus availability 2. In vivo study in broilers and pigs relationship with endogenous phytasic activity and phytic phosphorus content in wheat). Sci. FoodAgric., 70,69-74. 

Various dermatan sulfate derived di-, tetra-, hexa-, octa-, deca- and dodeca-saccharide mixtures have been prepared and purified (on a semi-preparative scale) by controlled depolymerization of dermatan sulfate using chondroitin ABC lyase, The pathways of InsPe hydrolysis by phytase from wheat bran of Triticum aestivum have recently been established. ... 

Liu, Z. H., H. Y. Wang, X. E. Wang, G. P. Zhang, P. D. Chen, and D. J. Liu. 2006. Phytase activity, phytate, iron, and zinc contents in wheat pearling fractions and their variation across production locations. Journal of Cereal Science 45 319-326. 

In his Natural History (1826), Pliny the Elder stated that those persons who are dieted npon fermented bread are stronger in body , which is an early statement on the health benefits of sourdough breads. Whole meals of cereals are a good source of minerals. Their bioavailability is limited, as they are often bound to phytic acid (myo-inositol-hexophospate). Wheat and rye contain about 1.2% of dry matter (Fretzdorff Briimmer, 1992). With the drop in pH during sourdough fermentation, endogenous phytases of the cereals are activated and the bound minerals are released (Fretzdorff Briimmer, 1992). Lactic acid bacteria and yeasts also possess phytase... 

Wheat bran phytase hydrol. prod, of sodium phytate. Mp 195-197° dec. 

A phytase has been isolated from the protein bodies of whole, milled, ungerminated barley, and this enzyme appears to be associated with the protein bodies of the aleurone layer (aleurone grains), a known storage site of phytin [141]. There is strong evidence (e.g. in wheat and rice) against the association... 

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