The effect of micro-wave irradiation at 2, 450MHz on potato starch was studied. The irradiation was carried out on the starch in a closed test tube at various temperatures (final temperatures, 85-150°C) and at various moisture levels (moisture contents of starch, 5-25%).
In contrast to the treatment by conductive heating (heat-moisture treatment), which changes the “B” X-ray diffraction pattern of potato starch to the “A” pattern, the micro-wave heating does not cause such transition, but weakens the sharpness of the pattern showing the increase of amorphous region. The sharpness of B-crystalline peaks of the treated starches was partially recovered by steeping in water. On the other hand, the gelatinization properties of micro-wave irradiated starches were similar to those of the heat-moisture treated starch.
The susceptibility of starch to the amylases (α-amylase, glucoamylase) was found to be increased greatly by micro-wave irradiation in parallel with the increase of the adsorption capability to amylases.

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In order to separate cyclodextrins (CD) from other dextrins obtained by the action of Bacillus macerans enzyme on starch, the fractionation using the ultrafiltration membrane was studied.
Five grades of membranes having cut-off molecular weight of 8, 000-100, 000 were used. As the result, the synthetic high polymer membrane having the cut-off molecular weight of 20, 000 was shown to be suitable. Using the membrane, permeate of CD's concentration of 90% could be obtained.

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To discuss the effect of addition of isolated soybean protein (ISP) on physical properties of starch noodle (Harusame), the noodles were made from potato, mung bean or broad bean starch mixed with ISP using pressure extruder, at 80°C unless otherwise mentioned. The extruded starch were heated in boiling water for 3min, washed with water, and dried immediately, or, frozen, thawed, drained and dried. The noodles were cooked in boiling water for 3min, washed and their transparency, swelling power, solubility and texture by tensipresser were measured for comparison and they were also subjected to organoleptic test. The results obtained were as follows.
1. The noodle from potato starch added by 5% ISP is transparent, higher tensile strength and elongation elastic modulus, less adhesiveness, being non-sticky, and lower solubility than the noodle from potato starch only. According to organoleptic test ISP was effective to make more acceptable, ranking next to noodles made in China.
2. By raising extrusion temperature from 80°C to 120°C the cooked noodle from potato starch only was extremely hard and sticky, being difficult to separate each other, however, the addition of ISP made the noodle more elastic and chewy, and, even in the case of ordinary drying, the noodles were not sticky and easy to separate each other.
3. Effect of freezing of noodle before drying on physical properties of cooked noodles were examined and the effects were evident in potato starch showing higher value in compression and tension test, and not in mung bean starch and mixture of potato and sweet potato starch (1:1). However by adding ISP physical properties of noodles from these starches were improved, being better than frozen noodles from potato starch.

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The continuous production of cyclodextrins (CD) using the ultrafiltration (UF) is described. This expperiment is based on the use of the membrane reactor system in which UF membrane modules, having the cut off molecular weight 100, 000 each, are equipped. The experimental procedures were as follows. Cyclodextrins mixture was prepared by the action of Bacillus macerans cycladextrin glucanotransferase on liquefied potato starch. This reaction mixture was pumped up to and recycled through the UF membrane reactor system. On the other hand, during the above mentioned operation, liquefied potato starch solution which was prepared by the continuous liquefying equipment was supplied continuously to the system as much as the volume of the permeate from the UF modules. The experiments were carried out for 6 days as the 1 cycle.
As the result, the recovery of CD in the permeate filtrate was 73% and the total yield of CD was 65.6%. The reaction efficiency of this continuous UF membrane reactor system was 2.6 times higher than that of the batch operation.

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The continuous reaction ot cyclodextrin (CD) formation From potato starch by immobilized cyclodextrin glucanotransferase (CGT-ase) on ion exchange resins is reported in this paper. As suitable carriers of the immobilized CGT-ase, high-porous type resins were selected, one was IRA-93 as a weakly basic resin, the other was HN-11-22 as a strongly basic resin (both are products of Organo Co.). Experiments were done using plug flow column.
At first, relationship between amount of immobilized enzyme on ion exchange resin and CD formation ratios for varied flow rates (SV) was studied. It was clear that CD formation ratio is greatly affected by the relationship between the amount of enzyme immobilized and the flow rate of substrate. when the amount of the immobilized enzyme is too much for the substrate solution's flow rate, the CD formation ratio is decreased. It is presumably due to other reactions of CGT-ase except the cyclization. The CD formation can be controlled to some extent by increasing or decreasing the SV value, i.e. flow rate of substrate according to the amount of immobilized enzyme.
In the second, the 30 days continuous running experiment was undertaken using immobilized CGT-ase on IRA-93 ion exchange resin by passing the liquefied potato starch solution through the resin column plug flow reactor. As the result, the activity of immobilized CGT-ase decreased with a half-life period of about 21 days. By decreasing the flow rate of the substrate solution stepwise starting with the initial SV value of 0.5 down to the final SV value of 0.26, the continuous running could be performed over a period of 21 days. The results here obtained led to a conclusion that an industrially practicable process could be established possibly by the cycling use of 3 to 4 columns in connection each filled with the immobilized CGT-ase.

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Starch samples were prepared from the seeds (cereals) of the three kinds of Gramineae plants growing wild in Japan: Chikara-shiba, Pennisetum alopecuroides Spreng., Enokoro-gusa, Setaria viridis Beauv.; and Ta-inu-bie, Echinochloa crus-galli Beauv. var. oryzicola Ohwi, in the yields of 16, 15 and 20% of the seeds, respectively.
These starches were examined on granular size and shape, contents of phosphorus and protein, X-ray diffraction pattern, iodine coloration, swelling power, solubility, amylogram, digestibility of raw starches by glucoamylase, and other properties.
Granular size of these three starches was comparatively small and the properties of them, including granular shape, almost resembled to those of corn starch. Each of starches showed the following characteristic properties: Chikara-shiba starch had a higher swelling power than sweet potato starch used as a control, and both starches of Enokoro-gusa and Ta-inu-bie showed high values in phosphorus content, 0.127 and 0.114%, respectively.

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Some chemical and physical properties of saffron starch were investigated. The results obtained were as follows.
1) The most popular size and the mean particle size of saffron starch were 10-20μm and 9.7μm, respectively.
2) The susceptibility of saffron starch granules to hog pancreatin was approximately 50% to that of normal-maize in the early reaction stages, but it was similar to that of normal-maize by 24 hr's reaction.
3) By scanning electron microscopy (SEM), we could observe pin holes and erosion on the surface of saffron starch granules attacked by pancreatin.
4) Amylose contents of saffron starch were determined to be 26.0% by the amperometric iodine titration and 29.2% by gel filtration of isoamylase-debranched starch.
5) The initiation temperature of gelatinization obtained by photopastegraphy and onset temperature by differential scanning calorimetry (DSC) of saffron starch were 59.5 and 65°C, respectively.
6) By X-ray diffractometry saffron starch showed. C_a-type pattern.
7) The initial pasting temperature of saffron starch measured by Brabender's amylography (of 8% starch samples) was 80.5°C, the maximum viscosity was 620 B. U., the breakdown was 320 B. U. and the viscosity-increase by cooling was 320 B. U.

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Cellulose is a polymer of 1, 4-β-glucan which is the most abundant organic substance on earth. It is deposited in crystalline microfibrils in the cell walls of higher plants during growth. Plant membranes may contain at least two UDP-glucose 4-β-glucosyltransferases, one with UDP-xylose that is involved in xyloglucan synthesis and the other may form cellulose. No one has not succeeded in the synthesis of cellulose at cell free system, although cellulose shouhd occur in plasma membranes. The question is “Where is the cellulose synthase in higher plants? and where do we go?”

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Potato starch granules were treated with heat-moisture, acid or 85% dimethylsulfoxide, respectively, and enzymatic digestibility of resulting starches were compared with those of intact potato and barley starch granules. Whereas digestibility of starches increased greatly after the heat-moisture treatment that of acid-treated and dimethylsulfoxide-treated starches remained essentially unchanged. It was suggested that crystalline structure of potato starch granules was most responsible to their low digestibility.
A bacterium was isolated that can utilize potato starch granules as a sole carbon source and identified as Bacillus circulans F-2. An extracellular α-amylase produced by this bacterium was purified and its digestive activity toward starch granules of various origins was compared to those of percine pancreatic and Streptococcus bovis α-amylases. The amylase from B. circulans F-2 proved to be most potent in digesting starch granules, especially, those of potato.
B. circulans F-2 produced amylase only when cultivated on starch granules. Other soluble (autoclavable) carbon sources, including maltose and gelatinized starches, have little or no activity in inducing amylase. Recently, starches crosslinked with epichlorohydrin were found to induce amylase as effectively as potato starch granules. These are autoclavable and, therefore, are very convenient carbon source for the production of B. circulans F-2 amylase.

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(1) Isopullulanase [EC. 3. 2. 1. 57 pullulan 4-glucanohydrolase] from Aspergillus niger was highly purified by acetone-precipitation, ion-exchange chromatography and gel-filtration. This enzyme hydrolyzed α-1, 4-glucosidic linkages adjacent to α-1, 6-linkages of pullulan to produce only isopanose (6-maltosylglucose). Its substrate specificity was different from those of pullulanase [EC. 3. 2. 1. 41] and isoamylase [EC. 3. 2. 1. 68]. From the results, it was expected that isopullulanase would be used as a suitable enzyme for the structural analysis of α-1, 4-:-1, 6-glucooligosaccharide. (2) Cell free extract of Aureobasidium pullulans synthesized pullulan from UDPG in the presence of ATP. It was suggested that pullulan Would be synthesized through a sugarlipid intermediate. (3) Thermoactinomyces vulgaris α-amylase hydrolyzed α-1, 6-linkages in partial hydrolyzates of pullulan as well as α-1, 4-linkages in starch and pullulan. Pseudomonas stutzeri maltotetraose-forming amylase hydrolyzed starch from non-reducing end to produce α-anomer of maltotetraose, whereas glucoamylase and β-amylase hydrolyze starch from non-reducing end to produce β-anomer. (4) Large scale preparation of isopanose and panose from pullulan was facilitated by the use of special enzymes, isopullulanase and T. vulgaris α-amylase.

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I have now taken you over some 35 years of research to the forefront of our research in this area at the present time. I hope I have given you an overall picture of this fascinating area of metabolism which is under such very elegant control by interrelated covalent and non-covalent mechanisms.
Our own work has led to the discovery of the action of the debranching enzyme amylo-1, 6-glucosidase, the mechanism of action of the branching enzyme amylo-1, 4→1, 6-transglucosidase, the discovery of the covalent control of glycogenl synthase by the multiple phosphorylation of glycogen synthase on a single polypeptide chain, the discovery of the mechanism of action of insulin to bring about the activation of glycogen synthase by dephosphorylation, the discovery of the inactivation of the cAMP-dependent protein kinase by insulin and most recently the discovery of the novel insulin second messenger peptides. I wish to acknowledge the work of many coworkers in my own laboratory and the scientists in many other laboratories throughout the world who have also contributed to our understanding of this field of research.
At present it is clear that covalent control by phosphorylation of key catalysts within the cell is a dominant theme for research in the mechanism of hormonal control. Perhaps similar mechanisms of action may apply in the case of plant cells as well. The late Dr. Earl Sutherland, one of my teachers, told me in his last conversation with me just before he died, that he was going to begin research in the mechanism of action of plant hormones.

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