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101.
102.
Effects of lipase,lipoxygenase, peroxidase and free fatty acids on volatile compound found in boiled buckwheat noodles 总被引:1,自引:0,他引:1
Tatsuro Suzuki Sun‐Ju Kim Yuji Mukasa Toshikazu Morishita Takahiro Noda Shigenobu Takigawa Naoto Hashimoto Hiroaki Yamauchi Chie Matsuura‐Endo 《Journal of the science of food and agriculture》2010,90(7):1232-1237
BACKGROUND: Relationships between buckwheat (Fagopyrum esculentum Moench) flour lipase, lipoxygenase and peroxidase activity, along with levels of individual free fatty acids (FFAs) and levels of headspace volatile compounds of boiled buckwheat noodles, were investigated for 12 different buckwheat varieties. Enzyme activities and FFA levels in flour were correlated with their respective varietal arrays of boiled noodle headspace volatile compounds, measured by gas chromatography–mass spectrometry. RESULTS: The volatiles hexanal, tentative butanal, tentative 3‐methylbutanal and tentative 2‐methylbutanal showed significant positive correlation with one another, indicating that they may be generated through similar mechanisms. These important volatile components of buckwheat flavor were also positively correlated with lipase and/or peroxidase activity, indicating that enzymatic reactions are important in flavor generation in boiled buckwheat noodles. On the other hand, pentanal, which showed no significant correlation with any enzyme activity, showed a significant positive correlation to the levels of C18:2 and C18:3 FFAs, suggesting the existence of a ‘non‐enzymatic’ and/or ‘uncertain enzymatic pathway’ for flavor generation in boiled buckwheat noodles. CONCLUSION: Lipase and peroxidase in buckwheat flour are important for flavor generation of boiled buckwheat noodles. This information is important for increasing desirable flavor of buckwheat products as well as for selecting varieties with improved flavor. Copyright © 2010 Society of Chemical Industry 相似文献
103.
Okihashi M Osakada M Uchida K Nagayoshi H Yamaguchi T Kakimoto K Nakayama Y Obana H 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2010,51(5):253-257
To conduct proficiency testing for the analysis of pesticide residues in processed foods, fortified samples of retort curry and pancake were examined. In the case of retort curry, heating and mixing were necessary at the time of preparation to provide a homogenous analytical sample. A mixture of 4 carbamates and 11 organophosphorus pesticides was spiked and 14 of them showed consistent results in the samples. In the case of pancake, 10 kinds of pesticides were added to the pastry. The prepared pastry was them cooked. The relative concentrations of most of the pesticides in the pancake were not affected and all the pesticides showed consistent results in the samples. These results showed that the two tested samples were suitable for proficiency testing. 相似文献
104.
105.
Dr. Fumika Karaki Sho Umemoto Karin Ashizawa Tomoya Oki Noriko Sato Takumi Ogino Naoto Ishibashi Ryoto Someya Dr. Kanako Miyano Dr. Shigeto Hirayama Prof. Yasuhito Uezono Prof. Hideaki Fujii 《ChemMedChem》2019,14(21):1840-1848
Although the advantages of sp3-rich, sterically complicated molecules in drug development have been pointed out, modern screening libraries are filled with planar, sp2-rich components. Compounds that are sp3-rich are difficult to synthesize, and thus we aimed to invent an efficient method to construct sp3-rich libraries. By modifying sp3-rich 7-azanorbornane scaffolds through click chemistry, we efficiently prepared a small set of compounds. These compounds were not only sp3-rich, but also had sufficient “lead-like” properties in view of molecular weights and hydrophobicity. Screening assays of this library provided weak κ opioid receptor agonists and growth hormone secretagogue receptor agonists with high hit rates. These results indicate that the 7-azanorbornane scaffold may be a “privileged structure” for lead identification in drug discovery. 相似文献
106.
Peerawut Yutthagowith Akihiro Ametani Naoto Nagaoka Yoshihiro Baba 《IEEJ Transactions on Electrical and Electronic Engineering》2011,6(4):324-330
This article presents calculations of tower surge responses and insulator voltages of an actual transmission tower including ground wires and phase wires. The partial element equivalent circuit (PEEC) method is applied as a simulation tool. Surge responses of the tower and insulator voltages calculated by the PEEC method are compared with electro magnetic transients program (EMTP) simulated results and experimental results collected from the literatures. The results calculated by the PEEC method agree well with the experimetal results, not only amplitudes but also waveshapes. © 2011 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
107.
The performance of the Taylor‐Couette flow apparatus as a heat sterilizer is numerically investigated. The destruction of Clostridium botulinum and thiamine (vitamin B1) was selected as model reaction. When Taylor vortices were formed in the annular space, the heat transfer significantly enhanced as compared to the case without vortex flow. As a result, the equivalent lethality calculated from the temperature field increased, which is regarded as a quantum leap. Conversely, the improvement of heat transfer induced destruction of thiamine. These results suggest that there is a trade‐off relationship between the enhancement of heat transfer and the avoidance of thermal destruction of nutritional components. In conclusion, the Taylor‐Couette flow sterilizer has the potential for process intensification in heat sterilization processes. 相似文献
108.
Hiroyuki Koide Satoshi Hirano Takafumi Ide Kazuhiro Saito Hikaru Suzuki Go Yasuno Yoshitaka Hamashima Sei Yonezawa Naoto Oku Tomohiro Asai 《Advanced functional materials》2021,31(3):2005641
Protein affinity reagents (e.g., antibodies) are often used for basic research, diagnostics, separations, and disease therapy. Although a lot of “synthetic” protein affinity reagents have been developed as a cost-effective alternative to antibodies, their low biocompatibility is a considerable problem for clinical application. Lipid nanoparticles (LNP) represent a highly biocompatible drug delivery agent. However, little has been reported that LNP itself works as a protein affinity reagent in living animals. Here, LNP is engineered for binding to and neutralizing a target toxic peptide in living animals by multifunctionalization with amino acid derivatives. Multifunctionalized LNP (MF-LNP) is prepared using amino acid derivative-conjugated lipids. Optimized MF-LNP exhibits nanomolar affinity to the target toxic peptide and inhibits toxic peptide-dependent hemolysis and cytotoxicity. In addition, MF-LNP captures and neutralizes the toxic peptide after intravenous injection in the bloodstream; in addition, MF-LNP does not release the toxic peptide in the accumulated organ. These results reveal the potential of using LNP as a highly biocompatible protein affinity reagent such as an antidote. 相似文献
109.
Sangho Koh Seika Imamura Naoto Fujino Masahiro Mizuno Nobuaki Sato Satoshi Makishima Peter Biely Yoshihiko Amano 《Journal of Applied Glycoscience》2019,66(4):131
The carbohydrate esterase family 1 (CE1) in CAZy contains acetylxylan esterases (AXEs) and feruloyl esterases (FAEs). Here we cloned a gene coding for an AXE belonging to CE1 from Irpex lacteus (IlAXE1). IlAXE1 was heterologously expressed in Pichia pastoris, and the recombinant enzyme was purified and characterized. IlAXE1 hydrolyzed p-nitrophenyl acetate, α-naphthyl acetate and 4-methylumbelliferyl acetate, however, it did not show any activity on ethyl ferulate and methyl p-coumarate. We also examined the activity on partially acetylated and feruloylated xylan extracted from corncob by hydrothermal reaction. Similarly, ferulic and p-coumaric acids were not liberated, and acetic acid was only detected in the reaction mixture. The results indicated that IlAXE1 is an acetylxylan esterase actually reacted to acetyl xylan. However, since IlAXE1 was unable to completely release acetic acid esterifying xylopyranosyl residues, it is assumed that acetyl groups exhibiting resistance to deacetylation by IlAXE1 are present in corn cob xylan. 相似文献
110.
Naoto Miyoshi 《Discrete Event Dynamic Systems》1997,7(3):275-293
Recently, Konstantopoulos and Zazanis (1992, 1994) and Brémaud and Lasgouttes (1993) derive the infinitesimal perturbation analysis (IPA) estimators for the stationary and ergodic G/G/1/ queue using Palm calculus, where neither regenerative structure nor convex property are required and the strong consistency is ensured by ergodic theorem. This work has been motivated by them and derives the smoothed perturbation analysis (SPA) estimator on the stationary and ergodic framework. The problem here is how to treat the catastrophic jumps on the sample path of the steady state and this is solved cleverly by using the Palm calculus. We deal with multi-class queues in this paper but our key formula is expected to be useful to any systems to which the SPA is applicable. 相似文献