著者

征矢野 清 泉田 大介

出版者

低温生物工学会

雑誌

低温生物工学会誌 (ISSN:13407902)

巻号頁・発行日

vol.61, no.1, pp.27-30, 2015-04-15 (Released:2017-06-15)

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Water temperature directly affects the physiological phenomena of fish categorized into heterothermic animal. In particular, the water temperature has been known as a major factor that controls the reproductive phenomena, such as sexual differentiation, gametogenesis, spawning, etc. In the present paper, we describe about the effects of water temperature on the reproductive phenomena in fish.

著者

平康 博章 因野 要一 西村 和彦

出版者

低温生物工学会

雑誌

低温生物工学会誌 (ISSN:13407902)

巻号頁・発行日

vol.60, no.2, pp.73-77, 2014-10-15 (Released:2017-06-15)

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Pulse combustion drying was used for dry preservation of lactic acid bacteria. An antioxidant i.e., 0.01% ascorbic acid or 1.0% glutathione was added to skimmed milk (5%) and trehalose (5%) to protect against desiccation of bacterial cells. The survival rate of dried lactic acid bacteria was > 90% on addition of the antioxidants, while addition of only skimmed milk and trehalose resulted in a 27% survival rate. Neither oxidized ascorbic acid nor glycine demonstrated this effect. Therefore, addition of an antioxidant to prevent peroxidation of the lipid membrane of microorganisms is effective in maintaining the viability of lactic acid bacteria subjected to pulse combustion drying. This the first study to achieve a sufficiently high survival rate of lactic acid bacteria in order to develop a microbiological agent using pulse combustion dryer.

著者

山口 良文

出版者

低温生物工学会

雑誌

低温生物工学会誌 (ISSN:13407902)

巻号頁・発行日

vol.66, no.1, pp.11-15, 2020 (Released:2020-09-01)

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Mammalian hibernation is a strategy to survive during harsh winter with severe hypothermia and immobility state. It has attracted many researchers for a long time but still remains to be elucidated. Studies in obligate hibernators such as ground squirrels, chipmunk, and bears have revealed that they undergo systemic body remodeling in a season-dependent manner prior to hibernation. By contrast, a facultative hibernator, Syrian hamster, can hibernate in an environment-dependent manner; when they are exposed cold and short photoperiod condition for several months, they begin to hibernate. This inducible hibernation allows researchers to study mechanisms and significance of hibernation under a laboratory condition, whereas exact nature of systemic body remodeling for hibernation in Syrian hamsters remain unclear yet. Using histology and exhaustive gene expression analyses, we compared summer-like hamsters and winter-like hamsters and found that Syrian hamsters extensively remodel white adipose tissues during a pre-hibernation period. Particularly, simultaneous up-regulation of gene expression in both lipid catabolisms and lipid anabolisms takes place in winter-like hamsters, which is a unique property of Syrian hamsters, a“food-storing” hibernator who ingests food stored in the nest during hibernation season.

著者

春日 純

出版者

低温生物工学会

雑誌

低温生物工学会誌 (ISSN:13407902)

巻号頁・発行日

vol.65, no.1, pp.1-6, 2019 (Released:2019-09-01)

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In order to survive severe winters without snow cover, boreal tree species have evolved superior freezing adaptation mechanisms. The freezing resistance of living cells in their aerial parts is well-controlled seasonally and exceeds -30°C in mid-winter. Although freeze–thawing can cause functional failure of their water transport system, boreal tree species have abilities to solve the problem and resume growth in spring. In this review, I introduce two topics on freezing responses of boreal tree species: (1) freezing adaptation mechanisms of xylem parenchyma cells which avoid intracellular freezing by deep supercooling, and (2) winter embolism formation mechanisms by which hydraulic architectures, vessels and tracheids, lose their function. In addition, possible relationship between freezing behavior of xylem parenchyma and their roles in embolism repair in early-spring is discussed.

著者

阿部 周司 遠藤 優人 阿部 洋一 村上 由里子 北上 誠一 朝倉 一好 梶原 一人

出版者

低温生物工学会

雑誌

低温生物工学会誌 (ISSN:13407902)

巻号頁・発行日

vol.61, no.1, pp.45-53, 2015-04-15 (Released:2017-06-15)

被引用文献数

1

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The effects of freeze-thaw cycles on the gelation of heat-induced gel from frozen surimi were studied. The rheological properties of the heated gel were measured by rheometer. The kinds of bands between the proteins of gel were estimated by solubilities of the gel for various solvents. Freeze-thaw cycles caused decreasing in breaking strength and breaking strain of the gel. The protein solubility rates of heated gel showed that rates of ionic bond and hydrogen bond were increased, whereas hydrophobic interaction, S-S bonding and more intensive bonding interaction were decreased by freeze-thaw cycles. From these results, it was suggested that the changes of protein solubility rates caused rheological property deterioration of the heated gel.

著者

津田 みどり

出版者

低温生物工学会

雑誌

低温生物工学会誌 (ISSN:13407902)

巻号頁・発行日

vol.61, no.1, pp.9-11, 2015-04-15 (Released:2017-06-15)

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Utilization of dry food and generation/conservation of body water plays a principal role in the tolerance of organisms against various environmental stresses such as aridity and high temperature. Here, I review two topics: evolution of dry bean use and bound water in stored bean pest. A large proportion of Callosobruchus seed beetle species are pests of stored, dry postharvest beans (i.e., seeds of legumes). However, the evolution of this feeding habit is poorly understood. We reconstructed the phylogeny of Callosobruchus and assessed which traits have been associated with the evolutionary origin or gain/loss of ability to use dry beans. Dry-bean use was phylogenetically constrained and associated with adaptation to arid climate. Thus, physiological adaptation to an arid climate renders beetles predisposed to become pests of dry beans. Body water conditions, associated with water conservation, at different life stages of insects under heat are yet to be understood. We compared loosely bound water (LBW) in seed beetles' body among life stages and between stored and non-stored bean pests at high temperatures, using ^1H-nuclear magnetic resonance spectroscopy. LBW was lowest in pupae. A non-stored bean pest retained higher LBW than a stored bean pest. I suggest an interpretation of the results.

著者

片桐 千仭 金子文俊 金子文俊 長嶋 剣 剣 佐﨑 元 元

出版者

低温生物工学会

雑誌

低温生物工学会誌 (ISSN:13407902)

巻号頁・発行日

vol.67, no.1, pp.23-29, 2021 (Released:2021-06-18)

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In this short review, we introduce various aspects of insect body lipids, which have been progressively found to have many crucial physiological roles. The body-surface of insects is covered with cuticular lipids, mainly hydrocarbons. The cuticular hydrocarbons are synthesized in specialized cells called oenocytes residing beneath the epidermis. The hydrocarbons synthesized are transported to the outermost layer, wax layer, by the circulating lipoprotein, lipophorin. Although the principal role of the wax layer is the protection of internal body from desiccation, the essential features vary depending on insect species and development stage. The diapausing pupae of large and small cabbage white butterflies change the thickness and unsaturation of their cuticular hydrocarbons from their non-diapausing ones. The cuticular hydrocarbons also contribute to chemical communications. The unsaturated hydrocarbons of male crickets play an important role for sex discrimination before copulation. Modern in-situ surface analytical methods have a potential to provide more abundant and precise information about the structure and physicochemical properties of the cuticular hydrocarbons. Recent ATR FTIR spectroscopic studies indicated the necessity of correction in the phase-separation model of cuticular hydrocarbons proposed by A. G. Gibbs.

著者

出原 信大 桑原 慎子 鈴木 伸吾 小髙 優子 藤川 清三 荒川 圭太

出版者

低温生物工学会

雑誌

低温生物工学会誌 (ISSN:13407902)

巻号頁・発行日

vol.63, no.2, pp.155-160, 2017 (Released:2018-04-14)

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It is known that some polyphenols with anti-ice nucleation activity decrease freezing temperature of the solution containing ice nucleators, resulting in maintenance of supercooling state of the solution for a long periods. In the previous study, recombinant proteins of Erwinia ananas ice nucleation protein, inaA with histidine-tag (His-inaA) were expressed in Escherichia coli cells and ice nucleation activity was detected in the cell suspension. In the present study, the purification and the characterization of His-inaA proteins from transformed E. coli cells were done to study the mechanism of anti-ice nucleation of these polyphenols in solutions containing inaA. When the extracts of E. coli cells expressing His-inaA were fractionated into soluble, membrane and inclusion body fractions, ice nucleation activities were detected in all three fractions. Then, His-inaA was purified from the soluble fraction by affinity column chromatography and ice nucleation activity of the purified His-inaA fraction was detected. Further, it is confirmed that anti-ice nucleation activity of polyphenols was detected in solutions containing His-inaA.

著者

松尾 光弘 松田 理登 石橋 孝明 菊池 優花 山北 伊織 盛 夏希 今村 鮎美 坂本 貴良 田代 佑治 酒井 泰良 山中 佳樹 西立野 興文 湯淺 高志

出版者

Japanese Society of Cryobiology and Cryotechnology

雑誌

低温生物工学会誌 (ISSN:13407902)

巻号頁・発行日

vol.61, no.1, pp.37-43, 2015-04-15 (Released:2017-06-15)

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Low temperature have been broadly applied for storage technique of various vegetable and crops. Sweetpotato is one of the most popular crops grown in tropical and temperature regions. Because sweetpotato, originated from semi-tropical plants, is susceptible to cold stress, severe chilling stress by itself causes deterioration and/or irreversible damage in sweetpotato tuber tissues. However, mechanisms involved in physiological and biochemical changes of sweetpotato under chilling stress remain unclear. Thus, we focused on the gene expression profiles of cold stress-responsive transcriptional factors and carbohydrate metabolisms of sweetpotato in response to chilling stress. A sweetpotato homolog of Drought Responsive Element Binding factor (swDREB) is induced in sweetpotato within 6 h after treatment of chilling stresses. The expression of swDREB under chilling stress was maintained until 3 d. Chilling stress sequentially upregulated the expression of β-amylase (β-AMY) and trehalose-6-phosphate phosphatase (TPP). Increase of amylase activity and sugar content was also observed in sweet potato under chilling stress, These results suggest that swDREB mediates the expression of β-AMY and TPP via a cold stress-responsive transcription factor cascade, leading to degradation of starch in sweetpotato tuber and accumulation of maltose and trehalose.

著者

近藤 皓介 原 賢二 阿部 周司 梶原 一人

出版者

低温生物工学会

雑誌

低温生物工学会誌 (ISSN:13407902)

巻号頁・発行日

vol.65, no.2, pp.71-74, 2019 (Released:2020-01-06)

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Hexagonal and cubic phases have been observed under atmospheric pressure as an ice crystalline phase. No study has reported the preparation of a cubic phase by directly freezing bulk water or by directly cooling the hexagonal phase. We hypothesize that the cubic phase is initially formed upon the crystallization of water and that it subsequently transitions to a hexagonal phase at a momentary rate. When pure water was used, it was not possible to capture the process of transferring to the hexagonal phase through the cubic phase at an integration interval of one second. However, when a 40 wt% aqueous glucose solution was used, it was possible to capture the process of transitioning from the supercooled liquid to the hexagonal phase through the cubic phase with an integration time of one second. This result is considered to indicate that the pure water may be instantaneously transferred from the supercooled liquid through the cubic phase to the hexagonal phase.

著者

村上 文哉 阿部 周司 梶原 一人

出版者

低温生物工学会

雑誌

低温生物工学会誌 (ISSN:13407902)

巻号頁・発行日

vol.65, no.2, pp.67-70, 2019 (Released:2020-01-06)

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Raffinose pentahydrate (R5W) was dehydrated at 30oC under a KOH saturated solution environment to prepare raffinose tetrahydrate (R4W). During the dehydration, the sample was measured by differential scanning calorimeter (DSC) and peak distortion was observed. Thus, an intermediate between R5W and R4W was detected. Even during the water absorption of R4W to R5W, DSC peak distortion was observed, indicating that an intermediate between R5W and R4W was generated. However, the intermediates of the dehydration and water absorption processes were considered to be different hydrates, named R4'W and R5'W, respectively. Moreover, the melting points of the hydrates from R5W to raffinose low hydrate were measured. These results suggest the existence of raffinose hydrate lower than R3W.

著者

高井 隆雄 鈴木 徹 佐藤 雄二 山田 有紀子

出版者

低温生物工学会

雑誌

低温生物工学会誌 (ISSN:13407902)

巻号頁・発行日

vol.43, no.2, pp.118-123, 1997-12-29 (Released:2017-06-19)

参考文献数

4

被引用文献数

2

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Recrystallization phenomena in frozen foods hurt the quality. In this study, rates of recrystallization of ice in frozen foods were determined for red meats of tuna and tofu cakes. These samples were frozen in methanol brine at -50℃ and stored at -50, -30, -20, -5℃ for maximum 80 days. Mean diameter of ice crystals in frozen foods were observed by microscope after these samples were fixed by freeze-substitution method and then sliced to very thin samples. The rates of recrystallization were k=135×10^3exp(-18.69/RT) and k=26×10^3exp(-1.6/RT) for tuna fish meat and tofu cake, respectively. These values were smaller by thousand times than the Zaritky's results. Zaritky's results were obtained at -20℃ final freezing temperature. The difference of final freezing temperature caused large difference in the recrystallization rates. The lower the final freezing temperature make the better storage conditions for frozen foods.

著者

菅野 正也 林 正和 村勢 則郎 網野 比佐子 北 潔

出版者

低温生物工学会

雑誌

低温生物工学会誌 (ISSN:13407902)

巻号頁・発行日

vol.54, no.2, pp.177-180, 2008-12-30 (Released:2017-06-19)

参考文献数

5

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For the establishment of successful cryopreservation of Caenorhabditis elegans, freezing survival of the nematode was investigated in the presence of dimethylsulfoxide. When nematodes were cooled to -20 ℃ with the rate of 0.2 ℃/min after ice seeding treatment at -3 ℃, survival rate of the nematode increased with the time of exposure to the DMSO solution before freezing. The rate was above 80% irrespective of the cooling temperature between -20 to -75 ℃. However, the nematodes hardly survived when they were quenched by liquid nitrogen after the pre-freezing at -20 ℃, The rate of freezing survival became higher with the decrease in the pre-freezing temperature before plunging into LN_2. Heating rate also affected freezing survival. Slow heating probably prevented rapid rehydration of the nematode and increased survival rate after thawing.

著者

米持 悦生

出版者

低温生物工学会

雑誌

低温生物工学会誌 (ISSN:13407902)

巻号頁・発行日

vol.51, no.1, pp.25-30, 2005-08-30 (Released:2017-06-19)

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Solid dispersions of drug in polymers are widely used to obtain the amorphous state of materials. However amorphous is unstable and easily crystallized. An estimation method for the physical stability of amorphous drug and a clarification of the effect of polymer on crystallization of amorphous drug in solid dispersion are primarily required. Generally solid dispersions were containing different ratios of drug and polymers, e.g. Polyvinylpyrrolidone (PVP), Hydroxypropylmethylcellulose (HPMC). The physical stability of solid dispersion was evaluated by the induction period of the crystallization under isothermal condition. The induction period of crystallization from amorphous drug was gradually delayed with increasing amounts of polymer. The crystallization of drug was prevented by the present of polymer. Drug-polymer interaction was recognized as one of the central cause, and the FT-IR spectra of solid dispersion suggested the interaction between drug and polymer. In spite of no interaction between Flurbiprofen and PVP, the solid disperseon containing them was stable. It is noted that the interfacial free energy between drug crystal and supercooled liquid and the activation energy of diffusion of drug molecules which related to nucleation was closely related to the drug crystallization. In the case of tolbutamide or flurbiprofen and PVP, the interfacial free energy was not affected by PVP contents. The activation energy of diffusion was increased with increase the PVP contents in the solid dispersion, suggesting that the crystallization of TB in solid dispersion would be affected by the diffusivity of drug. On the other hand, in the solid dispersion of FBP, the activation energy of diffusion was not changed by PVP contents. These reports suggested that the retardation of crystallization of drug induced by the coexistense of polymer could be related to the interaction between drug and polymer and the increase of the activation energy of diffusion.

著者

中島 一格

出版者

低温生物工学会

雑誌

低温生物工学会誌 (ISSN:13407902)

巻号頁・発行日

vol.45, no.1, pp.1-6, 1999-08-31 (Released:2017-06-19)

参考文献数

3

被引用文献数

1

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Blood products for transfusion in Japan are regulated by the pharmaceutical affairs law enacted by the Ministry of Health and Welfare. The quality system of GMP regulation for pharmaceutical products was introduced in 1976 and was applied for blood centers and blood products. GMP consists of the regulation for facilities and equipment (GMP hard), and quality management (GMP soft). The aims of GMP are prevention of human errors, prevention of contamination and quality defect of drugs, and constitution of quality system for manufacturing high quality pharmaceutical products. GMP contains GMP system, standard documents, management of manufacture, quality control, calibration, validation, management for complaints and recall, internal audit, and educational training. Blood centers in Japan have just started to use GMP and they look to be behind to other pharmaceutical companies particularly in the respect of GMP Soft. Therefore, we have to promote activities for carrying out GMP especially in quality management.

著者

渡邉 亜沙子 岡畑 恵雄 古澤 宏幸 星 美奈子 櫻井 実

出版者

低温生物工学会

雑誌

低温生物工学会誌 (ISSN:13407902)

巻号頁・発行日

vol.51, no.2, pp.137-140, 2005-12-30 (Released:2017-06-19)

参考文献数

3

被引用文献数

1

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The effect of trehalose on the aggregation of β-amyloid (Aβ) was investigated using quartz crystal microbalance (QCM) and circular dichroism spectroscopy (CD). Here we prepared three types of host Aβ-guest Aβ systems differing in a combination of their secondary structures: namely, β-sheet-β-sheet (system (1)), β-sheet-random coil (system(2)) and random coil-random coil (system(3)). The host Aβ was fixed on the electrode of QCM, and the guest Aβ was dissolved in a buffer solution. The host-guest interaction was monitored through a frequency shift (ΔF) of the quartz vibration: a larger ΔF value means the occurrence of a larger degree of host-guest aggregation. When disaccharide (trehalose, neotrehalose or maltose) was added in the above system, the time dependent profile of ΔF was significantly affected. In systems (1) and (2), any of these disaccharides depressed significantly the host-guest aggregation: maltose and trehalose exhibited the strongest effect in systems (1) and (2), respectively. Interestingly, in system(3), trehalose rather promoted the aggregation compared with the control (without disaccharide), while both maltose and neotrehalose depressed the aggregation as much as in the cases of systems (1) and (2). The results of systems (2) and (3) imply that trehalose more strongly interacts with Aβ in a random coil than that in p-sheets. In fact, CD measurements indicated that trehalose retarded the transformation of Aβ from a random coil to β-sheet. Taken together, these results open up the possibility that trehalose modifies the aggregation process of Aβ through its preferential interaction with the random coil state of Aβ.

著者

松嶋 卯月 KARDJILOV Nikolay LEHMANN Eberhard H. HERPPICH Werner B.

出版者

低温生物工学会

雑誌

低温生物工学会誌 (ISSN:13407902)

巻号頁・発行日

vol.58, no.1, pp.9-14, 2012-04-15

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Neutron imaging is a useful method for studying the water distribution of intact plants, due to the strong interaction of neutrons with hydrogen. This interaction provides high image contrast, even in the presence of small quantities of water. Moreover, the combination of neutron imaging with low-contrast tracer D_2O enables direct visualization of water flow and calculation of water flow rates at the tissue level in plants, at high resolution. This article introduces these two visualization methods, and reports our most recent experimental results using these methods.

著者

堀川 大樹

出版者

低温生物工学会

雑誌

低温生物工学会誌 (ISSN:13407902)

巻号頁・発行日

vol.52, no.1, pp.61-65, 2006-08-21

被引用文献数

1

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Tardigrades are hydrophilous invertebrates with four pairs of lobopodous legs forming a phylum and inhabit various environments throughout the world. Terrestrial tardigrades lose their body water almost completely and contract their body into a form called as "tun" when the surrounding water disappears. Although the dried tardigrades show no sign of life, they will recover their activity if a drop of water is given. This ametabolic dry state is called "anhydrobiosis". Anhydrobiotic tardigrades are known to tolerate a variety of extreme environments: they can survive a wide range of temperatures from -273℃ to 151℃, vacuum, hydrostatic pressure up to 600 MPa, ionizing radiation (X-rays, y-rays and ultraviolet rays) and chemicals (alcohol and methyl bromide). Tardigrades may provide a useful model system to study extreme environmental biology in the future, although the mechanisms of tolerance to extreme environments remain unknown. We will summarize extraordinary high stress tolerance in tardigrades and discuss the possible mechanism responsible for it.

著者

林 正和 網野 比佐子 北 潔 村勢 則郎

出版者

低温生物工学会

雑誌

低温生物工学会誌 (ISSN:13407902)

巻号頁・発行日

vol.57, no.1, pp.87-90, 2011-04-15

参考文献数

8

被引用文献数

1

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Cryopreservation of the nematode Caenorhabditis elegans in the adult stage is of importance as the nematode is a powerful model organism. In this study, we applied the protocol previously established for cryopreservation of the L4 nematode to the adult one. Survival rate of 84% was obtained as a result. When ice nucleation active bacteria, Pseudomonas syringae, was used for the simplification of ice seeding procedure instead of the use of a pre-cooled needle, survival rate of 82% was obtained after thawing. Moreover, a simple method of cryopreservation using a deep freezer and polystyrene foam was developed for a practical purpose. According to the observation under a cryomicroscope, eggs in the nematode body were found to freeze at ca. -20℃ when cooled at the rate of 0.2℃/min after ice seeding at -3℃ although the nematode body remained unfrozen down to -100℃.

著者

大川 拓 黄川田 隆洋 奥田 隆 櫻井 実

出版者

低温生物工学会

雑誌

低温生物工学会誌 (ISSN:13407902)

巻号頁・発行日

vol.56, no.1, pp.39-42, 2010-03-15

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Here the three-dimensional (3-D) structure of TRET1, a novel trehalose transporter from an anhydrobiotic insect, Polypedilum vanderplanki, was predicted by homology modeling in which the 3-D structure (1SUK) of GLUT1, glucose transporter from human was selected as a template. It was found that TRET1 has 12 transmembrane (TM) helices with an inward-facing conformation. Next, to explore the dynamics of the protein, we performed molecular dynamics (MD) simulation for the protein embedded in a hydrated phospholipid bilayer. The result of principal component analysis indicated that the protein has a hinge-bending motion, that is, the helices on the intracellular side come close or draw apart together. This dynamics may be essential for substrate uptake. Furthermore, we performed docking simulation combined with binding energy calculation to investigate the substrate selectivity of TRET1. As a result, it was found that trehalose more strongly binds to TRET1 than its isomer, isotrehalose, consistent with available experimental data.