The polysaccharide composed of only D-glucose was extracted with cold water from the endosperm of buckwheat (Fagopyrum esculentum) and purified through a column of DEAESephadex A-50 (C1-form), It was revealed to be a phytoglycogen from the results of IR-analysis, methylation study, and enzymic hydrolysis. The weight average molecular weight of the polysaccharide was determined to be about 14, 800 by gel chromatography. β-Limit dextrin prepared from the polysaccharide was digested with pollulanase and then isoamylase. A ratio of maltose and maltotriose to higher oligosaccharides in the digest supported Meyer's model for the structure of this polysaccharide .

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The retrogradation process of gelatinized corn, kuzu, sweet potato, and potato starch was studied using X-ray crystallinity and rheological methods. The intensities of peaks in the X-ray diffraction patterns increased gradually with increasing storage time. The crystallinity time profiles of starch gels showed the typical X-ray diffraction pattern. Although the storage modulus of all starch gels increased during storage, the rate depended on the storage conditions. The rupture strain of all starch gels decreased during storage, but the rupture stress increased. The time dependences of crystallinity of starch gels were in disagreement with those of moduli. The universal correlation between the relative rupture strain and whiteness was observed during storage of starch gels. The retrogradation process of starch gels was affected by the initial storage temperature.

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A fungus producing a novel neutral amylase, namely, the alkalitolerant strain TOF225, was isolated from samples collected in a residential dwelling in Tokyo, and it was identified as a species of Acremonium from its morphological characteristics. The fungus produced an extracellular amylase in the presence of starch and sodium carbonate or sodium bicarbonate. The maximal rate of production of the enzyme was obtained when the fungus was cultured aerobically at 28°C for 4 days in an alkaline medium. The enzyme was purified by chromatog raphy on DEAEToyopearl, Sephadex G50, MonoQ and Superdex 75. The purified enzyme was electrophoretically homogeneous and its molecular weight was 53, 000 daltons. The optimum pH and temperature for activity were 6.57.5 and 45°C, respectively. The enzyme was stable up to 30°C between pH 6.0 and 10.5 for 10 min, and it was thermostable in the presence of 1 mM CaCl₂ at temperatures up to 35°C. The isoelectric point of the enzyme was 5.94. This amylase is considered to be an alkalitolerant enzyme.

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The pore size distribution curves of rice, corn, potato, sweet potato and kuzu starches were investigated to elucidate the relationship between the types of A, B and C forms and their porosity. Pore size distribution curves in the regions of pore radii 4 to 10.5 Å and 10.5 to 300 A were determined by the micropore (MP) method from the moisture adsorption isotherms and the Barrett Joyner Halenda (BJH) method from the moisture desorption isotherms, respectively. Moisture content at higher water activity than 0. 4, saturated moisture content and hysteresis loop of B form (potato) starch were larger than those of C form (kuzu, sweet potato) and A form (rice, corn) starches. The maximum peak at the vicinity of pore radius 8 A was observed not in the A and C form starches but in the B form starch . The plots of pore volume in the region of pore radii 10.5 to 300 A and B form percentage gave a straight line with correlation coefficient of 0.955.

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Paper is commonly surface-sized by means of a size press. Surface sizing of paper is primarily done to decrease the porosity of the surface. Starch is the principal surface sizing agent used commercially. This study is concerned with starch-borate complex colloidal solution as sizing agent. The properties, i. e., dry strength, moisture-resistant property, the degree of sizing and resistance to flame, were improved in comparison with starch only. In the case of preparation of colloidal solution, the most suitable amount of borax added to starch is 1.5 mmol/g (starch). Successively by the addition of phosphoric acid to starch-borate complex colloidal solution there has been remarkable progress in the degree of sizing and resistance to flame.

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Cellobiose was synthesized from sucrose by coupling reactions of sucrose phosphorylase, xylose isomerase and cellobiose phosphorylase in the presence of a catalytic amount of inorganic phosphate (P_i). When a reaction mixture (10 ml) containing 200 mM sucrose (684 mg), 20 mM P_i, 0.26 U/ml sucrose phosphorylase, 0.034 U/ml xylose isomerase and 0.21 U/ml cellobiose phosphorylase in 50 mM imidazol-HC1 buffer (pH 7.0) was incubated at 37°C, the concentration of cellobiose in the reaction mixture reached 147 mM after 100 hr (yield 73%). Finally, 286 mg of crystalline β-cellobiose was recovered from the reaction mixture by charcoal column chromatography and crystallization.

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Durable deodorizer and fragrance incorporated into cyclodextrins (CD) have been developed to control the release rate of the reagents. The release rate of the deodorizer and fragrance were low compared with that prepared without CD . Thus prepared deodorizer adsorbed ca. 50% of cigarette odor and the volatile fragrance incorporated into CD was suitable for a long-term use .

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