Anion exchange chromatography was carried out by stepwise and gradient eluting method, using a high performance liquid chromatograph of Hitachi 655 A-11 type, Hitachi gell 3013 N of anion exchange porous polymer and the authentic samples of nucleic acid related substances. Eluting solution A: 0.045M NH₄Cl·0.0075M KH₂PO₄·0.0075M K₂HPO₄·2% CH₃CN, pH 8.2. Eluting solution B: 0.06M NH₄Cl·0.01M KH2PO4·0.01M K₂HPO₄·5%CH₃CN, pH 82. Eluting solution C: 0.105M NH₄Cl·0.0175M KH₂PO₄·0.0175M K₂HPO₄·6%CH₃CN, pH 3.0. After nucleosides and purine and pyrimidine bases were eluted by eluting solution A, 5'-mononucleotides and 2'(3')-mononucleotides could be eluted separately by the gradient method of eluting solutions A and B. And then, ADP and ATP could be separated continuously by eluting solution C. The nucleotides of 5'-mononucleotides, 2'(3')-mononu-cleotides, ADP, and ATP in several seaweeds and fishes were separated and determined by the above described method. The seaweeds contained 2'(3')-mononucleotides in large quantities and 5'-mononucleotides in small quantities. However, 5'-GMP, 5'-IMP, ATP could be scarcely observed in the seaweeds. The fishes contained a large quantity of 5'-IMP (90-350mg/100g). However, the contents of 5'-mononucleotides except 5'-IMP and 2'(3')-mononucleotides were little in the fishes.

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Starches from seven varities of Australian Standard White (ASW) and three varieties of Japanese domestic wheat (Dom) were compared to investigate factors affecting the functional (noodle-making) properties. Two peaks were detected in high-performance size-exclusion chromatography (HPSEC) for the native starches. These peaks were identified as amylose and amylopectin based on their iodine binding. Results obtained from HPSEC were, however, inconsistent with the values from chemical analysis. Although prime starches (PS) had a slightly higher iodine capacity than starch tailings (ST), little difference was observed in HPSEC. Debranching decreased the ralative amylose content, and produced a single amylose peak and three peaks which considered to be originated from the degradation of amylopectin unit chains. Starches from ASW were characterized in their higher ratio of the lower molecular weight unit chains. During beta-amylolysis, both amylose and amylopectin were partially hydrolysed and a new peak was detected. Amylopectin of ASW was also characterized in its higher relative degradation ratio. There was a little difference in the amylose degradation. Although it will be needed to compare for the purified amylose and amylopectin, starches from ASW and Dom were considered to be somewhat different in their amylopectin structure.

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The emulsifying properties of α-, β-and γ-cyclodextrins (CD) were investigated by use of a series of soybean oil-water (1:1, v:v) systems. The minimum CD concentration of oil emulsification was about 0.5% for α-CD, 0.25% for β-CD and 2% for γ-CD, respectively. The emulsifying activity (EA) and emulsion stability (ES) increased with increasing concentration of each CD. The amount of inclusion complexes formed during emulsification was related to the behavior of emulsifying properties. The lowering ability of interfacial tension at an oil/water interface (β-CD>α-CD>>γ-CD) was compatible with the order of minimum CD concentration for emulsification. EA and ES increased with increasing concentration of xanthan gum or tragacanth gum added in the emulsifying systems. The addition of sodium chloride did not affect EA and ES, while citric acid inhibited emulsification. The CD emulsion added xanthan gum or tragacanth gum was resistant to the freeze-treatment. EA and amount of inclusion complexes decreased with emulsifying temperature and the emulsion was not formed over 50°C even the addition of xanthan gum or tragacanth gum.

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The effects of lowering Ca concentration on the formation of rennet gel of casein micelle solution were investigated using a gel firmness tester. The changes in gel firmness after renneting was continuously measured under non-destructive conditions. The rennet gelation time, the initial gelation velocity and the maximum gel firmness were obtained from the renneting-gel firmness curves. It was found that the rennet gelation time increased with a decrease in the Ca concentration of casein micelle solution, while the initial gelation velocity and the maximum gelation firmness increased. When lysozyme was added into the casein micelle solution having a lower Ca concentration, the values of the three gel parameters became similar to those of the control samples. For these reasons, lysozyme can perform the same rolle as Ca during gelation of the renneted casein micelle solution.

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Changes in the rheological properties of "Aigyokushi" gels stood at room temperature were studied. 1) The values for textual properties of the slime extracted within 15min were very high and gelation occurred, but then they decreased by syneresis, and after a considerable amounts of water were released from the gel, the values increased again a little. 2) The value for the strain of Hookean body of "Aigyokushi" was the highest after standing for 2h, however, the strain of Voigt, Newtonean and plastoelastic body, was lowest at that time, respectively. 3) Both in the syneresis rate and total amounts of water released from the gels withhin 10h were greater than those of low methoxyl pectin gels. However, the calcium and galacturonic acid contents in the released water of "Aigyokushi" gels were lower than those of low methoxyl pectin gels.

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In the previous paper, we reported that browning products of glucosamine (BGA) lowered the proportion of the total polyenoic acids in total lipids of serum and liver of rats. In this paper, the fatty acid composition of serum and liver lipid classes in rats administered free glucosamine (FGA) and BGA were examined by means of thin layer chromatography (TLC) and gas liquid chromatography (GLC). The results obtained were as follows; (1) Serum and liver lipid could be separated into seven classes (sterol esters, triacylglycerines, free fatty acids, 1.2-, 1.3-diacylglycerines, sterols and compound lipids). (2) Fifteen to twenty fatty acids were found in the serum and liver lipid; the major fatty acids were C 16:0, C 18:0, C 18:1, C 18:2 and C 20:4. (3) Total polyenoic acid content in serum of the rats administered FGA was higher than that of the animals administered BGA.

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Lipase activity were examined in "Rice koji", "Soybean koji", "Okara koji" and "Sardine koji", molded with Aspergillus oryzae. Soybean koji", "Okara koji" and "Sardine koji" exhibited the lipase activity, while, the activity was negligible in "Rice koji".
Futhermore, effect of olive oil and pepton on the lipase activity was examined by using a mycelium. When A. oryzae was cultivated in the malt extract-dextrose medium, the lipase activity was not detectable. While, when the mycelium subsequently cultivated in the medium containing pepton, the lipase activity was high, but low in the medium containing olive oil. Lipase activity was mainly influenced by the nitrogenous compound in "Koji' such as pepton.

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The ascorbic acid contents at various parts of spinach leaves during storage were measured. The ascorbic acid contents of spinach leaf blades were higher than those of spinach petioles, and those of the inner leaves were higher than those of outer leaves. Ascorbic acid in outer leaves decreased during storage faster than in inner leaves. The relationhip between the rate of ascorbic acid reduction and storage temperature can be expressed as a following equation:
Loss%/day=e^{(0.102t+0.11)}
e: The base of natural logarithm t: Temperature (°C)

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To establish a rapid method for estimating maximum viscosity and breakdown of viscogram, effectiveness of Rapid Visco-Analyzer (RVA) was examined in the presence of ethylene diamine tetraacetic acid (EDTA (2K)) as an inhibitor of α-amylase. The results are as follows; 1. Viscosity parameters equivalent to maximum and minimum viscosity and breakdown of viscogram were measured by RVA under the following conditions for each measurement: (1) Amount of samples of whole meal: 4.3g, (2) EDTA solution: 25ml of 0.1M EDTA (2K), (3) Temperature and duration of measurement: 93°C for 12 to 13 minutes, (4) Items to be measured: maximum viscosity, minimum viscosity which was measured at 10min after the maximum viscosity was observed, and breakdown which was calculated from maximum viscosity minus minimum viscosity. This method gave good reproducibility as errors did not exceed about ±10 points from the average and its coefficient of variance was in an order of 1%. 2. Breakdown of viscogram began to reduce rapidly around 300 BU. When the slurry was prepared with 0.1M EDTA (2K) solution, breakdown of sprouted wheat flour was observed to be the same as the sound one. 3. A high correlation, r=0.649^* (n=13), was observed between RVA breakdown of whole meal and viscogram breakdown of wheat flour, and a higher one, r=0.908^*** (n=29), was observed in case of rice powder. The results showed that this method can be used practically for rapid estimation of breakdown of viscosity. 4. RVA had lower sensitivity to maximum viscosity and breakdown than viscograph in terms of range measured by the difference between the largest and the smallest values. The sensitivity was improved and the correlation was increased by holding the slurry at 60°C for two minutes for maximum viscosity and by gelatinizing at 90°C instead of 93°C for breakdown. (Ex. Correlation coefficient of wheat flour described above was improved from r=0.649^* to r=0.746**)

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When cyclodextrin (CD) was used as a bitterness masking agent to improve limonoids bitterness of canned Iyo orange segments, remarkable white cloud and precipitates were recognized in the syrup of canned fruits during storage. On the basis of solubility, shape of crystallines and spectrometric features, and of comparing with authentic samples and model inclusion compounds, the substances of the precipitates were elucidated.
The precipitate obtained from usual canned Iyo orange segments prepared without CD addition was identified to be hesperidin by infrared and ultraviolet absorption spectrometry.
The precipitate obtained from β-CD added group was presumed to be β-CD inclusioncompound containing components of Iyo orange juice sac membrane, fatty acids and sterols.The precipitate obtained from Dexyparl K-100 (mainly α-CD) added group was presumablyα-CD inclusion compound including a fatty acid fraction of Iyo orange juice sac membrane.
When the segment containing this crystalline inclusion compound was chewed in themouth, it gives very rough feeling on tongue and gritty to the teeth.

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The effects of sodium ascorbate on the pH, Hunter's white color values, degradation rate of chlorophyll, volatile isothiocyanates and their related components were investigated in the lightly pickled products of radish roots and takana leaves which were processed in brine containing various concentrations of sodium ascorbate. Sodium ascorbate had little effect on the pH of the all pickled products and their brine, Hunter's white color values of the radish pickles and the degradation rate of chlorophyll of the takana pickles. The amounts of the major pungent principles of radish roots, (Z)-and (E)-4-methylthio-3-butenyl isothiocyanates, were remarkably increased by addition of 0.1% and 0.25% of sodium ascorbate. When over 0.5% of sodium ascorbate was added, the amounts of the both pungent components were nearly equal to or less than those of the control. In the pickles of takana leaves, three major isothiocyanates (allyl, 3-methylthiopropyl, and 2-phenylethyl) and their related nitriles were also increased depending on the amounts (0.1-0.5%) of added sodium ascorbate, though their increased levels were not so high as in the radish pickles.

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Apparent lipase activity was reduced in the presence of pectin when the concentration of deoxycholate in the substrate emulsion was low. At the same time the surface area of oil droplets was considerably decreased, indicating the emulsion was destroyed and the available concentration of substrate of lipase was lowered. Pectin showed neither reduction of the lipase activity nor destruction of the emulsion when the the concentration of deoxycholate was high. However, it was not sufficiently clarified in this study whether the lipase repression was due to the destruction of the substrate emulsion by pectin.

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