Synthesis of glucosylxyluloside (Glc-Xul) by the action of sucrose phosphorylase [EC 2.4. 1.7] from Leuconostoc mesenteroides was studied . In the transfer reaction using equimolar amount of a-D-glucose-l-phosphate (G-1-P) and D-xylulose, about 25% of D-xylulose was converted into Glc-Xul, whereas only 17% of D-fructose was converted into sucrose when D-fructose was used instead of D-xylulose . In the transfer reaction using equimolar amount of sucrose andD-xylulose, more than 60% of D-xylulose was converted into Glc -Xul . It was found that more than 80% of added D-xylulose was converted into Glc-Xul when the molar ratio of sucrose to D-xylulose was increased to 3.

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Gelatinization of wheat and kudzu starches and the physical states of water in a system of starch, surfactant (SA), and water containing 56.0% or 74.9% water were studied with differential scanning calorimetry (DSC). With increases in the SA concentration in the starch gel, up to about 5% (w/w) of the starch, or with a stronger hydrophile-lipophile balance (HLB) of the SA, the onset temperature of gelatinization of starch rose, probably because of suppression of swelling of the starch eranules. DSC of frozen gel samples immediately after gelatinization of a starch gel containing 56.0% water without SA showed two endothermic peaks arising from restricted and free water . Just after gelatinization, the peak due to restricted water in wheat starch with an SA was observed as a single peak, but the peak due to restricted water in kudzu starch was not. With 74.9% water, restricted water was not present with either kind of starch, whether SA was used or not. Without SA, the amount of unfreezable water was higher than that with SA. Just after the gelatinization of starch, with a higher HLB of the SA, the amount of unfreezable water decreased, but during storage, the amount of unfreezable water increased.

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It has been suggested that the composition of intestinal microflora is closely related to the health and diseases of their host and strongly influenced by dietary components. 4^G-β-D-Galactosylsucrose (O-β-D-galactopyranosyl-(1→4)-alpha;-D-glucopyranosyl-(1→2)-β-D-fructQfuranoside, "Lactosucrose" : LS) is synthesized from sucrose and lactose by jS-fructofuranosidase . LS is slightly hydrolyzed by mammalian digestive enzymes and readily utilized by human intestinal predominant Bifidobacterium. It is known that such low-caloric sweetening agents as sorbitol and maltitol involve the side effect of diarrhea when orally ingested in a single large dose. We examined, by cooperation of 84 healthy volunteers, whether watery stool is caused by oral administration of LS. The amounts of LS administered were 0.2, 0.4, 0.6 and 0.8 g/kg of body weight. The administration of 0.2-0.6 g/kgBW of LS had no effect. Only one male had watery stool by the administration of 0.6 g/kgBW. On the other hand, by the administration of 0.8 g/kgBW, 32.5% of the males and 20.5% of the females had watery stool. Compared with sucrose and lactose, LS is more similar to lactose in the point of the ratio of watery stool. The maximum non-effective dose was estimated to be 0.6 g/kgBW for females and close to 0.6 /kBW for males . LS is less likely to cause watery stool compared with other low-caloric sweetening agents .

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The effect of β-glucooligosaccharides on the human intestinal microflora was studied. The syrup containing β-glucooligosaccharides was produced from glucose syrup as the raw material with the reactions of transglucosylation and condensation of microbial β-glucosidase . β-glucooligosaccharides were selectively utilized by Bifidobacterium spp., Lactobacillus spp. except L. fermentum and L. salivarius group, and Mitsuokella multiacidus group ; however, almost all of Eubacterium spp., Fusobacterium spp. and Clostridium perfringens group could notutilize the saccharides. The administration of β-glucooligosaccharides (4 g daily for 10 days) promoted the growth of Bifidobacteria and lowered fecal pH, in vivo. Furthermore, the volunteers never had diarrhea or flatulence and the consistency of feces was improved. From these results, it was suggested that β-glucooligosaccharides might be utilized as brandnew oligosaccharides for the improvement of intestinal microflora.

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The preventive effect of oligosaccharides against denaturation of carp myofibrillar protein during freeze-drying was studied by measuring the inactivation of Ca²⁺-ATPase . In the presence of oligosaccharides, the activity of Ca²⁺-ATPase decreased fast at the stage of initial several hours and then remained the same level during subsequent freeze-drying period . The preventive effect was estimated by the following epuation : e=Δlog k_D/a, where k_D is the first order rate constant for inactivation of Ca²⁺-ATPase at the early stage, and a is the concentration (%, g/100 ml) of oligosaccharide. The e values of various oligosaccharide-containing syrups examined were observed to become lower in the order of #360, #470, #350, #450. It was also found that a values were high when syrups containing large amounts of maltotetraose or oligosaccharides of higher polymerization degree and only small amounts of glucose and maltose were used. Another preventive effect was investigated for the minimum concentration (%, g/100 ml) of oligosaccharide to keep the full activity of myofibrillar Ca²⁺-ATPase . The concentration was estimated by extrapolation of the linear relation between the logarithm of remaining myofibrillar Ca²⁺-ATPase activity and oligosaccharide concentration . The minimum concentrations of every oligosaccharide-containing syrup to prevent perfectly the activity of myofibrillar Ca²⁺-ATPase from the inactivation during freeze-drying were within the limits of 5-9% .

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The effects of L-ascorbic acid (L-AsA) and sodium D-isoascorbate (D-AsA-Na) as an improver for breadmaking on the physical properties of wheat dough and starch were studied with use of a domestic breadmaking apparatus. D-isoascorbic acid (D-AsA) was oxidized to its dehydro-form in a yield of 50% by AsA oxidase in a neutral buffer solution, while L-AsA was about 90%. After addition of D-AsA or L-AsA (100 ppm) to the ingredients for breadmaking, D-AsA remaining in the dough during the mixing for 30 min was about 10%, while that of L-AsA was only 4%. Addition of 20 ppm D-AsA-Na to the ingredients for breadmaking increased the specific volume of the bread, while lower and higher concentrations gave a decrease. The addition of 50 ppm D-AsA-Na to the wheat flour increased the mechanical stability of dough during mixing as compared to that of the control or D-AsA, by farinography. Also, addition of D-AsA-Na in the dough showed filamentous and viscous states intermediate between those of L-AsA and control, respectively, as evaluated by scanning electron microscopy. Furthermore, the gelatinization temperature of starch in the dough containing D-AsA-Na (50 ppm) after mixing for 25 min decreased to about Sit which is intermediate between that of L-AsA and control. The results suggested that D-AsA-Naoxidized the SH groups of gluten mildly, followed by SS-cross linkage which changed the wrapping of the starch granules, thereby causing a decrease in the gelatinization temperature.

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Starch was separated from arrowhead corms . The starch contained a high level of amylose (25.6%) among the popular starches and 53 ppm of organic phosphorus, and showed Ca X-ray diffraction pattern. The d, p. n, and apparent d. p, distribution of amylose were 2840, 7080, and 570-21300, respectively. The c . 1. n of amylose and amylopectin were 420 and 20. 2, respectively. The onset gelatinization temperature measured by photopastegraphy was low at 49.5°C. The pasting properties of the starch by a Rapid Visco Analyzer were the most similar to those of sweet potato starch among some popular starches tested, but arrowhead starch showed a little lower pasting temperature and higher breakdown than sweet potato starch. The retrogradation tendency of the aqueous paste showed also similar to that of sweet potato starch.

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The authors have isolated a number of starches from wild plants in Japan, predominantly in Kagoshima Prefecture, and studied some of their chemical and physicochemical properties over the past 15 years. Among them, 72 starch samples were summarized in a table : these starches were classified according to the plant classification. The starch storage plants were discussed on the relationship between their storage organs (tissues) and the families of the plant classification.

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Among the properties of starch samples, four terms were selected, i. e., the mean of granular size, the apparent amylose content, the maximum viscosity and the gelatinization temperature, and analyzed statistically to get their histograms and correlations . The cross-shaped graphics for the four terms was attempted for the respective starch to visualize its characters . Based on the graphs the characters of starches from wild plants in Japan were discussed from aspects of their starch storage organs (tissues), their families in the plant classification etc .

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Structures of amyloses and amylopectins of rice (japonica and indica), maize (normal, sugary-2, amylomaize) and other nine origins have been examined by the methods involving newly devised procedures, and were found to be of characteristic in the origins. Ultra-centrifugation of crude amyloses from exhaustively defatted starches was effective for purification. Purified amyloses having iodine affinities (i. a., g/100 g) of 19.4-21.7 were confirmed to be free of amylopectin by gel-permeation chromatography. Amyloses had various sizes [number-average d. p. (d. p._n) 690-5090], numbers (1.9-12.4) of chains and average chain-length (c.1. 200-525), and were composed of linear and slightly branched (4.9-19.3 chains on average) molecules in various ratios (branched molecule; 11-70% by mole). Branched molecules appeared to be larger than linear molecules. Several varieties of rice and maize had generally a small amylose (d. p._n, rice 920-1110, maize 690-960) and branched molecule with a small number (d. p._n, rice 5.7-9.7, maize 4.9-6.1) of chains compared with the other plants. Branched molecules of rice (Nihonbare) and maize (normal, unknown sp.) had side-chains with wide d. p. distribution (about 6-4000) with a peak d. p. of about 20, and the rice branched molecule was 1.6 times as large as the linear molecule. Rice and maize amylopectins had i. a. of 0.39-2.57 and 0.8-4.63, respectively, and c. 1. of 19-21 and 20-32, respectively, while amylopectins from the other origins had i. a. of 0-0.51 and c.1. of 21-24. Amylopectins with a high i. a. were found to be composed of a large amount of very long chains (d. p. >100) and a small amount of short (weight-average d. p. about 20) or long (d. p._n about 45) chains. The very long chains appeared to be poorly branched. Amylomaize starches were comprised of amylopectin components with various sizes and an unusual, short chain component having d. p._n, of about 90 and about 2 chains on average. The amylose content of starch has to be calculated by considering amylopectin i. a, since its i. a. differed in the origins. Indica rice starches had the same amylose content (about 18%) as japonica rice starches.

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