フォロアの初期移動を考慮したリーダ追従型隊列誘導に関する研究

電気通信大学200

Purification and Characterization of α-Glucosidases from Spinach Seeds

Four molecular forms of α-glucosidase were isolated from spinach seeds by several kinds of chromatography. The molecular masses of α-glucosidases Ⅰ,Ⅱ,Ⅲ,and Ⅳ were 78,78,82 and 82kDa by SDS-PAGE, and 62,62,190,and 70kDa by gel filtration, respectively. α-Glucosidases Ⅰand Ⅱ showed similar enzymatic properties. The Km for soluble starch was about 10 times lower than that for maltose, and they had higher activity not only towards malto-oligosaccharides but also towards α-glucans. The optimum pH was 4.5-5.5 and about 50% of the activity remained after incubation at 71℃ for 20 min. On the other hand, α-glucosidases Ⅲ and Ⅳ showed similar enzymatic propreties. The Km for maltose was 3-4 times lower than for solble starch, and they had high activity toward malto-oligosaccharides but faint activity towards α-glucnas. The optimum pH was 4.5-5.0 and no activity was found after incubation at 70℃ for 20 min. However, anti-α-glucosidase Ⅲ serum precipitated specifically with α-glucosidase Ⅲ.α－グルコシダーゼの分子多型が各種クロマトグラフィーによりホウレンソウ種子から単離された。α－グルコシダーゼⅠ、Ⅱ、Ⅲ、Ⅳの分子量は、それぞれSDS－PAGEにより78、78、82、82kDA、ゲル濾過のより62,62,190、70kDであった。α-グルコシダーゼⅠとⅡは、可溶性デンプンを基質とした際のKm値がマルトースよりも約10倍低く、さらに、α－グルカンだけでなくマルトオリゴ糖に対しても高い活性を示すことから、同じような酵素的特性を持つことが示された。最適pHは4.5ｶﾗ5.5を示し、温度安定性は70℃、20分処理で約50％の残存活性を示した。一方、α－グルコシダーゼⅢとⅣは、マルトースを基質とした際のKm値が可溶性デンプンよりも3－4倍低い値を示し、マルトオリゴ糖に対しては高い活性を示すが、α－グルカンに対してはほとんど活性を示さないことから、同じような酵素的特性を有することが示された。最適pHは4.5－5.5、そして70℃、20分処理では活性が認められなかった。しかしながら、抗α－グルコシダーゼⅢ血清は、α－グルコシダーゼⅢに対してのみ特異的に沈降線を形成した

ホウレンソウ種子に存在するα-グルコシダーゼの分子多型変化

Two molecular forms of α-glucosidase were isolated from spinach seeds after storage at 4℃ by CM-cellulose column chromatography and gel filtration. The molecular masses of α-glucosidase A and B were 78 kDa and 82 kDa by SDS-PAGE, and 62 kDa and 70 kDa by gel filtration, respectively. α-Glucosidase A had high activity not only toward maltooligosaccharides but also toward α-glucans. The optimum pH was 4.5-5.5 and about 50% of the activity remained after incubation at 65℃ for 20 min. On the other hand, α-glucosidase B had high activity toward maltooligosaccharides but faint activity toward α-glucans. The optimum pH was 5.0 and no activity was found after incubation at 65℃ for 20 min. The enzymatic and immunological properties of α-glucosidase A and B were similar to those of α-glucosidase. Ⅰor Ⅱ, and α-glucosidase Ⅲ or Ⅳ, isolated from spinach seeds without 4℃ storage, respectively. These findings suggest that the α-glucosidase in spinach seeds is modified to be two molecular forms.4℃保存したホウレンソウ種子から2種のα-グリコシダーゼをCM-セルロースカラムクロマトグラフィーとゲル濾過により精製した。α-グルコシダーゼAとBの分子量はそれぞれSDS-PAGEで78kDA、82kDa、ゲル濾過で62kDa、70kDaであった。α-グルコシダーゼAはマルトオリゴ糖だけではなく可溶性デンプンに対して強い加水分解活性を示した。至適pHは4.5-5.5であり、65℃、20分処理後に約50％の残存活性を示した。一方、α-グルコシダーゼBはマルトオリゴ等に対して強い加水分解活性を示したが、可溶性デンプンに対してほとんど活性を示さなかった。至適pHは5.0であり、65℃、20分処理後に活性を消失した。α-グルコシダーゼAとα-グルコシダーゼBは、4℃保存を行わない種子に見出されたα-グルコシダーゼⅠ、Ⅱとα-グルコシダーゼⅢ、Ⅳにそれぞれ酵素化学的性質、免疫化学的性質が類似していた。これらの結果、ホウレンソウ種子に存在するα-グルコシダーゼの分子多型は2種類に収束されることが示唆された

Nanostructural Deformation Analysis of Calcium Silicate Hydrate in Portland Cement Paste by Atomic Pair Distribution Function

The deformation of nanostructure of calcium silicate hydrate (C-S-H) in Portland cement (PC) paste under compression was characterized by the atomic pair distribution function (PDF), measured using synchrotron X-ray diffraction. The PDF of the PC paste exhibited a unique deformation behavior for a short-range order below 2.0 nm, close to the size of the C-S-H globule, while the deformation for a long-range order was similar to that of a calcium hydroxide phase measured by Bragg peak shift. The compressive deformation of the C-S-H nanostructure was comprised of three stages with different interactions between globules. This behavior would originate from the granular nature of C-S-H, which deforms with increasing packing density by slipping the interfaces between globules, rearranging the overall C-S-H nanostructure. This new approach will lead to increasing applications of the PDF technique to understand the deformation mechanism of C-S-H in PC-based materials

Effect of different freezing methods on drip, texture, microstructure in fresh cheese (paneer)

Paneer is acid heat milk coagulated soft cheese popular in South East Asia. The shelf life is a major limitation for its utilization; even when kept under refrigeration. Similarly, the texture becomes flaky and fluffy after thawing. Freezing rate effects on the growth of ice crystals as well as microstructure damage that is responsible for the change in the textural quality of the Paneer. In this study, the effect of two-dimensional freezing by static air observed before and after freezing. Effect of freezing on panner were subject to analyses under slow freezing at -30°C, rapid freezing at -80 °C and supercooling freezing conditions. The quality evaluation carried out by means of drip loss, textural analysis, and microscopic observation. By using this technique, it was possible to decide the supercooling freezing is significantly best method for preserve the paneer to keep required hardness, low drip and small cracks and rupture in a microstructure in compare to another method

Studies on the Chironomid Midges Collected in Hokkaido and Northern Honshu

Collections of adult chironomids were conducted by H. Suzuki at 5 localities in southwestern Hokkaido in September, 1997, by M. Sasa in the Aizu area, Fukushima, in October, 1997, and by K. Kamimura in Aomori Prefecture in August 1997, by using light traps at night or by sweeping with insect net during daytime. The species identification was made after the specimens were individually mounted on slides in gum-chloral medium. In Hokkaido, 9 species were identified with specimens collected in the campus of Hokkaido University, 16 species including 5 new species at Ginzan, 14 species including 5 new species at Misumai, 8 species including 2 new species at Kyogoku, and 4 species at the foot of Mount Tarumae. In the Aizu area, 2 species were identified with specimens collected on fluorescent lamps at Koriyama, 4 species, including a species belonging to Protanypus, a genus new to Japan, were collected on the shore of Lake Inawashiro and another 4 species, including a new species of a new subgenus, Pseudosmittia (Hibarasmittia) hibaraundecima, were collected on the shore of Lake Hibara. In Aomori Prefecture, 2 species, including a new species of genus Macropelopia, at Sukayu, 2 species at Asamushi, and 3 species at Fukaura, including a new species of genus Tanytarsus, were identified

Studies on the Chironomid Midges of Tsushima and Iki Islands, Western Japan : Part 1. Species of Chironominae Collected on Tsushima

Collections of adult chironomid midges using light traps in night time and by sweeping with insect net in daytime were carried out by Suzuki during 3 days period from 24 to 26 March, 1998, on Tsushima Island, located on the channel between the Korean Peninsula and Kyushu, Japan. The specimens were preserved in 70% alcohol, screened under stereomicroscope in the laboratory, and a part of them were dissected and mounted individually on slides in gum-chloral medium. A total of 512 adult male specimens were examined this time and 253 among them were identified as belonging to the subfamily Chironomidae, and the rest 259 were those belonging to other subfamilies. The former group was further studied in details, and identified as belonging to 48 spepcies, among which 13 are the species already recorded from Japan, one species, Micropsectra junci (Meigen, 1818) is a new record to Japan, and the rest 34 are recorded in this paper as new species

Studies on the Species of Family Chironomidae (Diptera) Collected on Minamidaito Island, Okinawa, South Japan. Part 1.

Collections of the specimens of the insect family Chironomidae were conducted on a small island of Minamidaito, Okinawa, southwestern Japan, during the period from March 26 to 29, 2001, with insect net in daytime and light traps after sunset and to next morning, and also by rearing adults in the laboratory from bottom sediments. The adult males were dissected and individually mounted on slide glasses in gum-chloral medium, and their species were identified. As the results, they are classified into 31 species including 16 new species. It is again a surprising fact that so many the species of this family, including new species, were collected from such a small island

Studies on the Chironomid Midges of Tsushima and Iki Islands, Western Japan. : Part 2. Species of Orthocladiinae and Tanypodinae Collected on Tsushima.

Collection of the adult specimens of the insects family Chironomidae were carried out by Suzuki during the period from March 24 to 26, using light traps at 2 localities and by daytime sweeping with insect net at 18 localities on Tsushima Island. By microscopic examinations of 377 individually mounted slide specimens, 127 were found to be belonging to the subfamily Chironominae, and were classified into 48 species including 34 new species, and were described in our previous report (Sasa and Suzuki, 1999). The rest 250 specimens were classified into 56 species (including 31 new species) of the sub family Orthocladiinae, and 6 species (including 2 new species) of the sub family Tanypodinae. It was again demonstrated that this island is very rich in the chironomid fauna, and many new species are again added by the present studies. It is also shown that rather rare species so far collected only in central or eastern Japan are found in this remote island located in western Japan near the Asian continent