Changes in free sugar, protein and starch contents of morning-glory callus cells and culture medium during growth were determined. Changes in the activities of cell wall-bound invertase, cytoplasmic acid and neutral invertases, UDPGppase, sucrose synthetase(sucrose synthesis and sucrose cleavage activities)and sucrose phosphate synthetase of the cells were also determined. Sucrose in the medium disappeared by 35%at 5 days and 85%at 10 days after inoculation. Conversely, fructose and glucose contents increased in the medium and the fructose content was larger than that of glucose during growth. The maximum content of sucrose in the cells was at 10 days and those of reducing sugars was at 5 days. The ratios of glucose and fructose were O.9:1in early stage of culture(5 to 10 days)and Q.75:1in middle and final stages of culture(after 15 days). Acid invertase activities in cell wall and cytoplasmic fractions showed the maximum in early stage(5 days)and a maximum in final stage. Both enzyme activities varied largely and were closely correlated during growth. In cytoplasma, neutral invertase activity was as large as acid invertase activity and did not vary largely during growth. Sucrose synthetase showed the maximum activity at middle stage of culture(15 days)and large change in its activity during growth. Sucrose phosphate synthetase activity did not vary largely during growth. Based on these data, sucrose metabolism of morning-glory callus cells was discussed.

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Recently we prepared a new syrup from the mixture of starch and sucrose by the action of cyclodextrin glycosyltransf erase. This syrup contained mainly sucrose (GF) and oligosaccharides, such as glucosylsucrose (G2F), maltosylsucrose (G3F) and maltotriosylsucrose (G4F) terminated sucrose at the reducing end. In addition, this syrup contained a small amount of maltooligosaccharides, such as glucose (G), maltose (G2) and maltotriose (G3). In this report, we tried to analyze the sugar composition in this syrup by High Performance Liquid Chromatography. Various sugars, such as fructose (F), G, GF, G2, G2F, G3, G3F were separated and quantitatively determined under the following conditions:, column, μ BONDAPAK/Carbohydrate(4×300 mm) ; solvent system, water/acetonitrile=20/80; flow rate, 2 ml/min or 4 ml/min. Because of less solubility of the oligosaccharides larger than G2F in this solvent system, it was difficult to analyze these oligosaccharides.

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A gas chromatographic method has been developed to determine the oligosaccharides (sucrose, raffinose, stachyose and verbascose) in beans and their products. Sugars are extracted from foods with 80% ethanol, an aliquot of the extract is dried, trimethylsilylated, and TMS-sugars are determined by GLC . Precision study showed when the contents of a sugar is below 1% and more than 1%, the average of coefficients of variations (the range of coefficients of variations) are 4 .1% (0.00-16. 43%) and 3.8% (0.44-8.08%), respectively. Recovery of added raffinose in extracts were 89.3-102.0%.

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Physical and chemical properties were investigated for amylomaize starches, which were irradiated with gamma rays at total doses of from 0.02 to 60 Mrad. 1) Under below a dose of 1 Mrad, although reducing power, iodine absorption and the limits of β-amylolysis were hardly affected, solution viscosity of the all starches used (five varieties) decreased greatly. Among tested starches, amylomaize starches were more resistant to radiation damage than the other. The cause of difference in sensitivity to gamma irradiation which observed between amylomaize and other starches, was further investigated . The results confirmed that this difference was independent of amylose content and the degree of crystalinity of starch. Irradiated starches became soluble in cold water at above a dose of 30 Mrad . Reducing power increased, and absorption peak of the iodine complex was shifted toward shorter wavelength. The findings seemed to indicate molecular degradation . Furthermore, the recognition of glucose, maltose and oligosaccharides as breakdown products evidenced that the irradiation caused hydrolytic cleavage of the starch molecules. 2) The insoluble residues of irradiated starches were characterized by the determination of DP, β-amylolysis and gel filtration of the pullulanase hydrolyzates. DP of insoluble residues from irradiated starches were 30-40. But these residues contained considerable amounts of high molecular weight components eluted at void volume on Sephadex G-50 column . The elution patterns of the pullulanase hydrolysates of these residues on Sephadex G-50 column showed a marked decrease in amylose fraction. But X-ray diffractograms and scanning electron photomicrographs of the residues did not show a significant changes as compared with those of original starches. The properties of insoluble residues from irradiated starches were compared with those of Nageli amylodextrins and of a-amylase treated starches prepared from non-irradiated starches. The results obtained indicated that the residues differed significantly from amylodextrins and α-amylase treated starches in characteristics . These findings suggested that the starch granules were destroyed at random in both crystalline and amorphous parts by gamma irradiation . 3) In vitro digestion of amylomaize starch granules with pancreatic a-amylase was improved with increasing radiation dose levels. But in vivo digestibility of this starch in rats showed a tendency to be lowered by irradiation, and concomitant increase in weight of feces and cecum contents was also observed. From the results in vivo observation, it seemed that starch granules on the irradiation received some structural modification, in which they could not be cleaved by amylolytic enzymes of digestive tract.

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