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J. -K. Huang K. C. Keudell Su-Jin. Seong W. E. Klopfenstein L. Wen M. O. Bagby R. A. Norton R. F. Vesonder 《Biotechnology letters》1996,18(2):193-198
Summary A new microbial isolate, Bacillus sp. U88, transformed 12-hydroxyoctadecanoic acid to 12,15-, 12,16- and 12,17-dihydroxyoctadecanoic acids when grown aerobically in 1 % yeast extract medium at 30°C and shaken at 250 rpm for 5 days. These three dihydroxyfatty acids were derivatized with Trimethylsilyl ether and identified by GC-MS analysis. The yield of 12,15-, 12,16- and 12,17-dihydroxyoctadecanoic acids after 5 day incubation were 2.8 %, 7.1 % and 1.1 %, respectively.Names are necessary to report factually on available data; however the USDA neither guarantees nor warrants the standard of the product, and the use of the name by USDA implies no approval of the product to the exclusion of other that may also be suitable. 相似文献
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Jun Seong Jeong Min Jee Kim Jeong Sun Park Keon Hee Lee Yong Hun Jo Jun-ichi Takahashi Yong Soo Choi Iksoo Kim 《Journal of Asia》2021,24(2):135-147
The yellow-legged hornet, Vespa velutina nigrithorax (Hymenoptera: Vespidae), invaded South Korea in 2003 through Busan metropolitan city, which is located in the southeast region of the country. Previous studies aiming to trace the origin of V. velutina in Korea used a portion of mitochondrial (mt) COI and detected a single haplotype common to the site of origin. However, no subsequent study on invasive dynamics such as additional entry and/or another site of entry has been performed. In this study, segments of mt COI, CytB, and lrRNA were sequenced from 238 individuals collected in 11 Korean and two Japanese localities, but no variation in each gene was observed. Thus, we developed two intergenic spacer (IGS) sequences from the publicly available mt genome of V. velutina, which provided substantially increased variability (i.e., 19 haplotypes with 1.74% maximum sequence divergence in 1,129–1,146-bp-long concatenated sequences). Population genetic analyses using the concatenated sequences unexpectedly provided higher genetic diversity estimates in the northwest and southwest regions, both of which also harbor international cargo ports, than in the southeast region, in which Busan is located. Furthermore, this genetic result was roughly concordant with our questionnaire survey demonstrating that V. velutina was observed in apiaries located in the northwest and southwest regions up to 2012, when there was no reported prevalent distribution of the hornet beyond the southeast region. These results collectively suggest that the northwest and southwest regions of Korea are additional sites of V. velutina entry to the country, independent from the southeast region origin. 相似文献
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A novel extraction method was developed aiming at increasing the stability of enzymes in organic solvent media. Horseradish peroxidase (HRP), inactivated in a tetrahydrofuran (THF)/water (1:1, v/v), regained and maintained its activity when HRP was extracted by adding a THF/benzene mixture to the original solution. However, the HRP activity was drastically lowered in the enzyme-free blank solution that had been formed by employing the same extraction procedure. As a result, the reactivation after the extraction is believed to depend on enzyme history, and might be arisen from an irreversible structural change of the enzyme. 相似文献