Starch lintnerized

Robin, J. P., Mercier, C., Charbormiere, R., and Guilbot, A. (1974). Lintnerized starches. Gel filtration and enzymatic studies of insoluble residues from prolonged acid treatment of potato starch. Cereal Chem. 51, 389 05. 

CGTase Activity Assay. Aaivity was measured by the Pharmacia Phadebas Amylase Assay at pH 6.0, 60 C in O.IM sodium acetate (100 ppm Ca+ " ) for 15 minutes using B, stearothermophilus alpha-amylase as a standard. Alpha-amylase preparations were assayed under the same conditions. One Phadebas unit is defined as the amount of enzyme that will catalyze the hydrolysis of 1.0 micromole of glucosidic linkages of Lintner starch per minute at 6OOC, pH 6.0. 

The CGTase was observed to retain 100% of its activity when incubated in 5% Lintner starch O.IM sodium acetate pH 5.0 (50ppm Ca" "" ") for 50 minutes at 95 while Termamyl and B. stearothermophilus alpha-amylases retained 0% and 38% activity, respectively. In the absence of starch substrate and Ca+ +, the residual CGTase activity is approximately 95% when incubated at 80 C, pH 5.0 for 40 minutes while no activity remains in the case of the alpha-amylases (Figure 4). 

Figure 3. Aaion pattern from Lintner starch at 60 pH 6.0.

Another special type of t. by thermal modification is Zulkowsky starch which is used in the same applications as Lintner starch. 

The characteristic of beta amylases of reaching a limit in the hydrolysis of starches gives the investigator a simple criterion for ascertaining whether his amylase preparation has been freed from alpha amylase, which usually accompanies beta amylase in nature. If the hydrolysis of Lintner s soluble potato starch at pH 4.5 ceases when approximately 64%... 

The ratio of dextrinogenic to saccharogenic activities for pancreatic amylase, measured with Lintner s soluble potato starch under comparable conditions at 40°, is approximately 2 to 45,57 The achroic point is reached in the hydrolysis of potato starch by highly purified pancreatic amylase when approximately 20% of the glucose linkages of the starch have been broken.41... 

Influence of Dialysis During Hydrolysis upon the Extent of the Hydrolysis of Lintner s Soluble Potato Starch by Pancreatic Amylase (Data of Alfin and Caldwell 1)... 

The amylase of Aspergillus oryzae causes a very rapid decrease in the viscosity of its substrates and a very rapid disappearance from its reaction mixtures of products which give color with iodine. When examined under favorable conditions71 at 40° with Lintner s soluble potato starch, the achroic point was reached with highly purified maltase-free amylase when approximately 12% of the glucose linkages of the substrate had been ruptured. 

When measured at 40° with Lintner s soluble potato starch, the ratio of the dextrinogenic to the saccharogenic activities is approximately 6 to 1 for the amylase of Aspergillus oryzae. This value is given by both crude and purified preparations of the amylase if the measurements are carried out under comparable conditions. This constancy in the ratio of these two activities has led to the conclusion that, like pancreatic amylase, the amylase of Aspergillus oryzae is not accompanied in nature by beta amylase. Reacting mixtures of the amylase of Aspergillus oryzae and starch exhibit alpha mutarotation.72... 

Similarly, the addition of maltose to reaction mixtures failed to influence the extent of the hydrolysis of Lintner s soluble potato starch... 

Very highly purified preparations of alpha amylase of malted barley give a value of approximately 4 to 1 for the ratio of their dextrinogenic to their saccharogenic activities when the measurements are made at 40° with Lintner s soluble potato starch.81 Under the same conditions approximately the same value is obtained with products precipitated by alcohol from malted barley extracts which had been treated to inactivate beta amylase.23 81 However, a constant value for these ratios is not proof that beta amylase is entirely absent. There is at present no satisfactory way of making certain that malted barley alpha amylase is not contaminated with traces of beta amylase. The crystallization of alpha amylase from malted barley has been reported since this manuscript was written.79... 

It was Brown and Morris (15) in 1888 who employed Raoult s method. They reported a value of 30,000 for the molecular weight of amylodextrin, a degradation product of the hydrolysis of starch. Subsequently Lintner and Dull (16) also using cryoscopy reexamined amylodextrin, and reported the molecular weight as 17,500. In a third paper, Rodewald and Kattein (17) in 1900, measured the molecular weight of starch by osmotic pressure experiments carried out on aqueous solutions of starch iodide. They obtained somewhat higher molecular weights, 36,700 and 39,700. 

---