The major amylolytic enzyme present in Meicelase, a commercial crude cellulase preparation from Trichoderma viride, was purified by consecutive column chromatography, and characterized as a glucoamylase [EC 3.2. 1.3] . The specific activity was brought to 18.3 units of soluble starch-saccharifying activity/mg of enzyme protein, and the enzyme showed a single band on polyacrylamide gel disc electrophoresis . Some properties of the purified glucoamylase were investigated . The optimum pH and the optimum temperature for the activity of the enzyme were pH 5 .0-5.5 and 60°C, respectively. The enzyme was stable over the range pH 5.0-7.0 at 4°C and was completely inactivated by heating at 90°C for 10 min. Hg²⁺ completely inhibited the enzyme, but other metalions tested had little effect on the activity at the concentration of ions used (1 mM) . The action of the enzyme on amylopectin, glycogen, soluble starch, short chain amylose (DP=17.3), maltose, isomaltose and panose was studied. Glucose was the sole hydrolysis product found in digests of these substrates. At the same substrate concentration (0.075%, w/v) and enzyme concentration, the initial rates of glucose production from amylopectin, soluble starch, short chain amylose and maltose were in the proportions 8 : 8 : 8 : 1.

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High-amylose corn starch, which contains 50% amylose, was oxidized with sodium hypochlorite and several properties of the oxidized starches were examined. The oxidation was carried out at a pH of 11 and at 40°C. The amount of oxidant added was 1-8% as available chlorine per starch. Yield of the high-amylose starch was 90% at 8% oxidant level and that of the ordinary starch was 80% at 60% level. Viscosity was measured by the Amylography at 15% starch concentration, for viscosity was not indicated at 7% starch concentration. Transmittance of the paste was measured by the Photopastegraphy and the transmittance of high-amylose starch was very low even at 90°C. As the degree of oxidation increased, the viscosity was lowered and the transmittance was increased. Swelling power and solubility was measured at 90°C. The swelling power was decreased slowly between 1-4% oxidant level and then rapidly between 5-8%. The solubility was increased linearly in proportion to the amount of oxidant. More carbonyl and carboxyl groups were formed, as the degree of oxidation increased. Functional group contents of high-amylose starch were slightly low as compared with ordinary starch. X-ray diffraction patterns showed that even 8% oxidant level gave little effect in crystalline regions.

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Changes in the activities of major starch-degrading enzymes -α-amylase (α-1, 4-glucan 4-glucanohydrolase, EC 3.2.1.1), /9-amylase (α-1, 4-glucan maltohydrolase, EC 3.2.1.1) and a-glucan phosphorylase (α-1, 4-glucan: orthophosphate glucosyltranferase, EC 2.4.1.1) were determined in the rice seed endosperm during germination in the dark at 30°C. Furthermore, the apparent changes occuring simultaneously in the endosperm tissue and isolated granules therefrom were followed by means of scanning electron microscope. α -Amylase activity was detectable only after about 4 days of seed imbibition and reached the peak activity at about 10 days.β-Amylase activity, although present already in the endosperm of ungerminated seeds, increased after about 4 days and showed the peak activity after 10-12 days. Phosphorylase activity was very low and hardly detectable throughout the course of germination (Fig. 1). The endosperm tissue of the ungerminated rice seed was composed of the square-pillar shaped cells arranged side by side and radiating from the center of the seed grain. These cells cotained a large number of starch granules of various sizes (mostly oval in shape) and the space between the starch granules was filled with cementing materials (Figs. 2 and 3). The compound starch granule consisted of a number of starch granulum which had characteristic polyhedral shape (Figs. 4 and 5) (“Starch granulum” used here is defined as the unit granule of compound starch and “starch granule” is defined as the whole starch consisting of an amyloplast). At the early stage of germination, the cementing materials embedding the starch granules disappeared, thus facilitating the contact of degradative enzymes to starch granules (Fig. 6). With the progress of germination, the square-pillar shaped cells were broken and concurrently, the amyloplast membrane disappeared. Starch granules, freed from coat materials, are ready to attack of degradative enzymes and there are some starch granules in the process of decomposing into granulums (Figs. 4, 7, 9 and 12). At this stage, however, starch granulums with pits on their surfaces were rarely observed in contrast to the case of germinating barley seeds (Fig. 8). At the later stage of germination, the pits on the surface of starch granulum increased in number, but the errosion did not progress further toward the interior of the granulum (Figs. 10 and 13). However, the average size of the starch granulum became smaller and there are indications showing the granulum being erroded over the whole surface (Fig. 11). Thus, the degradative patterns of starch granule and granulum in germinating rice seeds are quite different from those of starch granules in germinating barley seeds. These observations were discussed with special reference to the structure of starch granulum in rice seeds.

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Potato starch suspensions in water and water extract of potato were heated at 100°C for 5 min. The pastes, thus prepared, were kept at about 5°C and the progress of retrogradation was estimated by the method of glucoamylase digestion and X-ray diffraction. As a result, the more pronounced retrogradation and crystallization were observed in the paste prepared with potato extract than in that with water. This fact may suggest that the cytoplasmic fluid contributes to the crystallization of starch to form the granule in vivo.

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Starches from a very wide range of botanical materials have been isolated. Amylose contents of starches were measured by potentiometric titration of their iodine-binding capacities. The amylose contents of nonwaxy starches are in a range of 15% (rice) to 30% (pea). The iodine staining properties of amylose of a range DP 16 to 330 have been examined in terms of color, intensity of stain, and wave length of peak light absorption. Under the standard conditions used, amylose of DP 21 give a red color with a absorption peak at 510 nm, 28 purple 540, 34 violet 560, 41 blue violet 580, and 61 to 330 blue with 600 to 630 nm, respectively. Starches of corn, potato, kidney bean, sorghum and waxy rice have been fractionated into their component amylose and amylopectin. During the fractionation procedure, a fraction (C-fraction), which is precipitated by forming a complex with isoamylal cohol but not with n-butanol, was fractionated from corn-, kidney bean- and sorghum starches, respectively. Their properties have been investigated in detail. The properties of C-fraction show that they are essentially similar to amylopectin in nature. We studied the raising properties of the Japanese special confections "Arare" and"Okaki" which raise vigorously by themselves without any aids of gasses produced by fermentation or baking. Moreover, a method for the analysis of sugar mixtures containing glucose, fructose, sucrose, maltose, lactose and dextrin was investigated.

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The following is an enumeration of achievements of Hayashibara Kabushiki Kaisha after 1959 in the starch sugar industry .
1. Development of processes for obtaining glucoamylase from R, delemer and for production of pure glucose (DE 97) with the enzyme.
2. Discovery of pure 9-amylase in wheat bran and development of a high-maltose-syrup process with the enzyme.
3. Screening of debranching-enzyme-producing strains from numerous cells, and development of processes for production of amylose, maltose and maltitol with such strains and their uses in foods and pharmaceuticals.
4. Screening of glucose-transferase, and development of a process for production of oligosylfructose with the enzyme .
5. Development of a process for production of a polysaccharide, pullulan, and its uses as food ingredients and non-pollutant plastics.

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The phosphate derivatives of starch, the structure of maltitol, the character and application of starch sugar alcohols as well as the changes of starch granules during gelatinization with a novel photopastegraphy method have been studied. The study of starch sugar alcohols in particular revealed their new properties by hydrogenation, magnifying the application field of the starch sugar alcohols : Maltitol was applied for a low calorie sweetener as it was calorie free . Hydrogenated starch syrup solid has been watched as reduced sweetness food material with excellent stability and as an additive for powder.

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