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91.
Humio Kurasawa Yoshiaki Kanauchi Tadakatsu Wakayama Toshiro Hayakawa Ikuo Igaue 《Bioscience, biotechnology, and biochemistry》2013,77(12):2913-2916
Varoius piericidin analogues (PS-I, -II and -III in Fig. 2) were synthesized from three 4-acetoxy-6-formylpyridines by Wittig reaction to determine the structure-activity relationships. New type inhibitors, 5-alkenyl-2, 3-dimethoxy-4-hydroxy-6-methylpyridines (PS-IV) were synthesized by intramolecular cyclization. 相似文献
92.
In the course of investigation of alicyclic hydrocarbon-utilizing microorganisms, five strains of ethylcyclohexane-utilizing bacteria were isolated from soil samples.Among those bacteria, the strain S6B1 that was identified as Alcaligenes faecalis, showed the best growth in shaking culture.The strain S6B1 was found to produce 4-ethylcyclohexanol from ethylcyclohexane.This substance separated from culture broth was purified and identified to be trans-4-ethylcyclohexanol by the use of NMR. 相似文献
93.
Masakuni Okuhara Yoshiaki Kubochi Tokuya Harada 《Bioscience, biotechnology, and biochemistry》2013,77(9):1376-1380
Many strains of yeast which can utilize n-alkanes as the sole source of carbon were isolated from flowers and fruits. Among them, a strain, OH23, identified as Candida tropicalis, formed acidic substances from n-alkanes. The principal products from n-alkanes with odd and even numbers of carbons were identified as glutaric and adipic acids, respectively. The culture conditions for their formation were investigated. n-Pentadecane and n-hexadecane were the best substrates for the formation of glutaric and adipic acids, respectively. Yields of 170 mg of glutaric and 64 mg of adipic acid were obtained from 100 ml of media containing 4% (v/v) n-pentadecane and n-hexadecane, respectively, and 0.5% casamino acids. 相似文献
94.
A polyuronide, main component of the water extract of achine of Ficus awkeotsang MAKINO (on-gyo-tye), was purified by ion-exchange chromatography on DEAE-cellulose. The polyuronide (Fraction IB) is homogeneous electrophoretically and consists mainly of galacturonic acid. Optical rotation of Fraction IB is and content of methoxyl group is trace. In periodate oxidation of Fraction IB, molar ratio of galacturonic acid residue and periodate consumption was 1, and formic acid formation was very small. Periodate oxidation product of Fraction IB was oxidized further with bromine and the resulted substance was hydrolyzed. In the hydrolyzate, presence of large amount of tartaric and glyoxylic acids and small amount of tartronic acid were detected by paper chromatography. Reduced viscosity of aquous solution of Fraction IB increased with decreasing of the concentration of Fraction IB solution. From these results, it was deduced that Fraction IB has a linear structure of 1→4 linkage of d-galacturonic acid, probably α-linkage. 相似文献
95.
Yoshiaki Nakahara Masanao Matsui Kenji Mori 《Bioscience, biotechnology, and biochemistry》2013,77(11):2243-2245
A novel synthetic method of 3-substituted furans was developed and syntheses of perillen and dendrolasin are described. 相似文献
96.
Yoshiaki Iwamuro Michiko Murata Koichiro Kanamaru Yoichi Mikami Takuro Kisaki 《Bioscience, biotechnology, and biochemistry》2013,77(2):525-526
The aroL gene, encoding shikimate kinase of Brevibacterium lactofermentum, a coryneform glutamic acid-producing bacterium, was cloned. Recombinant plasmids containing the aroL gene caused elevated levels of shikimate kinase synthesis in B. lactofermentum. It was found that in addition to the aroL gene, the aroB and aroE genes, encoding dehydroquinate synthase and shikimate dehydrogenase, respectively, also existed on these recombinant plasmids, in complementation tests with various Escherichia coli and B. lactofermentum aromatic amino acid auxotrophs. The aroL, aroB and aroE genes of B. lactofermentum are located closely on the cloned DNA fragment, in that order. It was shown that at least these three aro genes form a cluster on the chromosome of B. lactofermentum. 相似文献
97.
Masaru Enomoto Wataru Kitagawa Yoshiaki Yasutake 《Bioscience, biotechnology, and biochemistry》2013,77(8):1324-1327
The quinoline antibiotics aurachins C, D, and L, and a structurally simplified analog of aurachin C were synthesized from 1-(2-nitrophenyl)butane-1,3-dione via reductive cyclizations of δ-nitro ketone intermediates, with zinc or iron as key steps. The results of antimicrobial tests indicate that the N-hydroxyquinolone nucleus mimics the electron carrier in the respiratory chain more strongly than the quinoline N-oxide nucleus. 相似文献
98.
Young Man Park Kazuya Matsumoto Yoo Jin Seo Min Jeung Kang Hidetoshi Nagashima 《Biological Rhythm Research》2013,44(1):39-51
The healthy 455 subjects above 60 years of age were questioned on their sleep habit inventory and the morningness-eveningness questionnaire. We analyzed the effects of age and sex on sleep habits and sleep-related trouble. Bedtimes on weekdays and weekends became earlier with aging, and women went to bed significantly later than men did. The length of sleep on weekdays slightly increased with aging, and it was longer for men than for women. The number of urinations and awakenings during nocturnal sleep and the amount of daytime napping increased with aging. The score on morningness-eveningness shifted toward the morning type with aging. In comparison with men, women had significantly longer sleep latency; and a higher percentage of subjects who reported that they sleep for only a short time, have sleep trouble, have received medical treatment for their sleep trouble, and take sleep medication. From these results, we deduced that the phase of sleep shifted forward in subjects above 60 years of age, and they showed frequent interruptions during nocturnal sleep and long daytime napping. We discussed the factor of gender difference in sleep in relation to social and cultural factors, particularly the household activities of women. 相似文献
99.
Mi Young Yang Mary Beth Hilton Steven Seaman Diana C. Haines Kunio Nagashima Christina M. Burks Lino Tessarollo Pavlina T. Ivanova H. Alex Brown Todd M. Umstead Joanna Floros Zissis C. Chroneos Brad St. Croix 《Cell reports》2013,3(5):1457-1464
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100.
Michael J. Miller Yoshito Chikaraishi Nanako O. Ogawa Yoshiaki Yamada Katsumi Tsukamoto Naohiko Ohkouchi 《Biology letters》2013,9(1)
What eel larvae feed on in the surface layer of the ocean has remained mysterious. Gut contents and bulk nitrogen stable isotope studies suggested that these unusual larvae, called leptocephali, feed at a low level in the oceanic food web, whereas other types of evidence have suggested that small zooplankton are eaten. In this study, we determined the nitrogen isotopic composition of amino acids of both natural larvae and laboratory-reared larvae of the Japanese eel to estimate the trophic position (TP) of leptocephali. We observed a mean TP of 2.4 for natural leptocephali, which is consistent with feeding on particulate organic matter (POM) such as marine snow and discarded appendicularian houses containing bacteria, protozoans and other biological materials. The nitrogen isotope enrichment values of the reared larvae confirm that the primary food source of natural larvae is consistent only with POM. This shows that leptocephali feed on readily available particulate material originating from various sources closely linked to ocean primary production and that leptocephali are a previously unrecognized part of oceanic POM cycling. 相似文献