Wheat amylase

Amylase occurs in many plants, such as barley, wheat, rye, soy beans, and potatoes, where it is generally accompanied by some a-amylase. [ -Amylase initiates hydrolysis at the nonreducing end of an amylose or amylopectin chain, and removes maltose units successively until the reducing end of the molecule is encountered in amylose or a branch is met in amylopectin. ( -Amylase is used commercially in the preparation of maltose symps. After P-amylase hydrolysis of amylopectin there remains a P-amylase limit dextrin. ( -Amylase has been used as a probe of the fine stmcture of amylopectin (43-46). 

Previously, it has been reported that the amounts of eukaryotic initiation factors in wheat germ extract prepared by a common method were deficient for the translation of some kinds of mRNAs including a-amylase mRNA and (i-globin mRNA [2]. Therefore, it can be expected that the activity of wheat germ extract prepared by a common method can be enhanced by the simple addition of extract containing deficient initiation factors. In this study, a wheat germ extract was further purified partially by ammonium sulfate fractionation... 

KOIKE D, YAMADERA K, DiMAGNO E p (1995) Effect of a wheat amylase inhibitor on canine carbohydrate digestion, gastrointestinal function, and pancreatic growth. Gastroenterology. 108 1221-9. 

Levels of the enzyme a-amylase in wheat grains also affect breadmaking quality. Flour for bread-making requires low levels of a-amylase and this is favoured by a dry ripe dormant grain. The Falling Number (Hagberg) Test is used to determine a-amylase levels. A... 

The enzymes in wheat, and hence in flour, that often cause problems in the bakery are present in the seed to make nutrient available to the seed. Similarly, this is why sprouted wheat causes problems if it is allowed to get into flour. Thus, the a-amylase is low in mature wheat grains but rises rapidly on germination. In bread, a low, but not too low, level of a-amylase is desirable since it produces sugars to feed the yeast and opens up the structure. Deliberate additions of malt flour were once common, but are now rarely made, to increase the amylase level. 

The Hagberg Falling Number test only just qualifies for this section as it is an effective way of measuring the a-amylase activity of wheat or flour. It has the considerable advantage that it is unaffected by any added fungal a-amylase. In addition, it only requires a supply of distilled water and electricity - there is no need for chemical glassware or any reagents. 

When Canadian wheat flour was the norm in British bakeries, with a falling number as high as 600, it was desirable to introduce malt flour to increase the a-amylase to feed the yeast and open up the structure of the crumb. 

A literature survey indicated that very little work has been done to produce an optimal cellulase system as described above. Here, we used solid-state fermentation (SSF) to achieve this objective. SSF processes, such as the "koji" process, have been used extensively for amylase production on wheat bran in Japan its application was extended to cellulase production on wheat bran and Ugnocellulosic materials by Toyama (13), Since then, wheat bran has become an important substrate for producing various products by SSF (14-20), In this study, we tested various lignocellulosic substrates for the production of cellulase and )3-glucosidase from T, reesei QMY-1 by SSF. 

Other enzymes may be Inhibited, too. Llener (43) recently summarized the literature on amylase Inhibitors In wheat and their effectiveness against stored product pests ... 

American-Maize Products Co., Hammond, IN), ordinary corn (Maltrin M-250, Grain Processing Corp., Muscatine, lA) and potato (Avebe America Inc., Hopelawn, NJ) hydrolysates were obtained commercially. Wheat, cassava, rice, and amylomaize VII starches were enzymatically hydrolyzed using a thermally stable alpha-amylase from Bacillus licheniformis (E.C.3.2.1.1 ... 

Here are some questions relating to this activity. Enzymes such as amylase are destroyed by heat—how could you confirm this experimentally If you boil one starch solution for only a few minutes and a second starch solution for an excessively long time, which will be light blue and which will be dark blue when you add iodine Many instant Cream of Wheat cereals contain papain, an enzyme related to amylase. Can it be said that these instant cereals are being digested before reach-ing your mouth ... 

It is now supposed that gibberellic acid stimulates the hormonal production of a-amylase (and, probably, of /9-amylase and others) in the aleurone layer surrounding the endosperm starch-reserve. Gibberellic acid released 400 mg. equivalents of D-glucose per g. in 90 hours in wheat grains, with a maximum hydrolytic activity after 60 hours. The effect on /9-amylase was thought to be a release (to the extent of 85%) from the protein-bound, insoluble form.876... 

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