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81.
A novel 15C compound, pseudoalteromone B (1), possessing a novel carbon skeleton, was obtained from a marine bacterium Pseudoalteromonas sp. CGH2XX. This bacterium was originally isolated from a cultured-type octocoral Lobophytum crassum, that was growing in cultivating tanks equipped with a flow-through sea water system. The structure of 1 was established by spectroscopic methods. Pseudoalteromone B (1) displayed a modestly inhibitory effect on the release of elastase by human neutrophils. 相似文献
82.
Li-Hsueh Wang Jyh-Horng Sheu Shih-Yao Kao Jui-Hsin Su Yung-Husan Chen Yu-Hsin Chen Yin-Di Su Yu-Chia Chang Lee-Shing Fang Wei-Hsien Wang Yang-Chang Wu Ping-Jyun Sung 《Marine drugs》2012,10(11):2415-2434
The structures, names, bioactivities and references of 105 natural products obtained from gorgonian corals belonging to the family Plexauridae with an Indo-Pacific distribution are described in this review. All compounds mentioned in this review were obtained from gorgonian corals belonging to the genera Astrogorgia, Bebryce, Echinomuricea, Euplexaura and Menella. 相似文献
83.
Major fish bacterial diseases in Korea are edwardsiellosis, streptococcosis, and vibriosis. Among vibrionaceae, Listonella anguillarum, Vibrio harveyi, V. ichthyoenteri, and Photobacterium damselae were identified as causative organisms of vibriosis in flounder. In this study, we developed a multiplex PCR method using the RNA polymerase β subunit (rpoB) gene, known as a housekeeping gene for identification of Vibrio spp. causing vibriosis in flounder. Three pairs of PCR primers were designed based on the rpoB sequence of three species, V. harveyi, V. ichthyoenteri, and P. damselae. The PCR assay, using a mixture of six primers, yielded amplicons of 601, 434, and 533 bp in V. harveyi, V. ichthyoenteri, and P. damselae. None of the untargeted species yielded an amplicon. The detection limits for pure culture in kidney were 2.5 × 104 cfu/g kidney for V. harveyi, 2.5 × 105 cfu/g kidney for V. ichthyoenteri, and 2.5 × 106 cfu/g kidney for P. damselae. From the colonies on TCBS agar plates of different samples, 632 Vibrio spp. isolated from aquacultured flounder between 2004 and 2010 were identified by the multiplex PCR method. As a result, 265 strains (41.9 %) were V. ichthyoenteri; 115 strains (18.2 %) were V. harveyi and 72 strains (11.4 %) were P. damselae. 相似文献
84.
Binod Prasad Luitel Na-Young Ro Ho-Cheol Ko Jung-Sook Sung Ju-Hee Rhee On-Sook Hur 《Journal of Crop Science and Biotechnology》2018,21(5):499-506
A total of 47 core collections of pepper (Capsicum chinense Jacq.) conserved in National Agrobiodiversity Center (NAC) were studied under field condition at Jeonju over two consecutive years (2015 and 2016). All accessions were characterized for their 14 qualitative and 16 quantitative characters. Results revealed that both qualitative and quantitative characters exhibited wide variation among the studied germplasm. Distribution of fruit characters (fruit length, width, and fruit wall thickness) among the accessions was positively skewed. Of the 47 accessions evaluated, 38.3% accessions had conical shaped fruits and mature fruit color was predominantly red (51.1%), orange (21.3%) and yellow (14.9%). Principal component analyses revealed that (i) 56.64% of the qualitative (fruit shape, color and fruit surface) variation and (ii) 89.42% of the quantitative (plant width, height and fruit maturity days) variation were explained by the first two components. Clustering revealed two groups and dendrogram revealed morphological variation among accessions. The phenotypic diversity exists in this core collections provide valuable information to improve agronomic traits in pepper breeding program. 相似文献
85.
Coat and hair color: hair cortisol and serotonin levels in lactating Holstein cows under heat stress conditions
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Jalil Ghassemi Nejad Byong‐Wan Kim Bae‐Hun Lee Kyung‐Il Sung 《Animal Science Journal》2017,88(1):190-194
The deleterious effects of heat stress on animal health are being increasingly recognized. This study aimed to determine hair cortisol (HC) and serotonin levels in lactating Holstein cows under heat stress conditions with different coat and hair‐cut color. Forty‐five multiparous lactating Holstein cows (days in milk = 130 ± 47, body weight = 753 ± 85 kg) were divided to two main groups of over 80% black coat color (BC) and over 85% white coat color (WC) visually observed based on registry certificates and subdividing to black hair sample (BH) and white hair samples (WH) in 2 × 2 factorial arrangements. Hair samples were taken from the forehead of the individuals. Higher HC levels were observed in BC than WC cows (P < 0.05). No differences were found in HC levels between BH and WH groups (P > 0.05). Serotonin levels showed no difference between BC and WC (P > 0.05). Interaction between coat color and hair color was not significant (P > 0.05). The cortisol levels in hair are not affected by pigmentation. However, pigmentation within the coat alters cortisol levels. In conclusion, white coat color retains less cortisol than the black coat. Therefore, white coats are preferable for dairy cows under heat stress conditions. 相似文献
86.
To increase the spinning speed of poly(trimethylene terephthalate) (PTT) fibers, polystyrene (PS) was selected as an additive
polymer in the PTT matrix. Mixing of the immiscible PS with PTT led to an increase in spinning speed up to 5,500 m/min. PS
was employed to improve the extensibility of the matrix PTT in the spinning process as it can prevent PTT molecular orientation.
Experimental results show that the mixing of PS achieved this. The elongation at break of spun fibers increased with the amount
of PS. PS addition prevented fiber orientation, especially amorphous orientation, and improved drawability, and as such, increased
spinning speed up to 5,500 m/min. 相似文献
87.
Sung PJ Li GY Su YD Lin MR Chang YC Kung TH Lin CS Chen YH Su JH Lu MC Kuo J Weng CF Hwang TL 《Marine drugs》2010,8(10):2639-2646
Two new 12-hydroxybriarane diterpenoids, designated as excavatoids O (1) and P (2), were isolated from the octocoral Briareum excavatum. The structures of briaranes 1 and 2 were established on the basis of extensive spectral data analysis. Excavatoid P (2) is the first metabolite which possesses a 6β -chlorine atom in briarane analogues. 相似文献
88.
Chih-Yang Liu Tsong-Long Hwang Mei-Ru Lin Yung-Husan Chen Yu-Chia Chang Lee-Shing Fang Wei-Hsien Wang Yang-Chang Wu Ping-Jyun Sung 《Marine drugs》2010,8(7):2014-2020
A new bioactive sterol glycoside, 3β-O-(3′,4′-di-O-acetyl-β-d-arabinopyranosyl) -25ξ-cholestane-3β,5α,6β,26-tetrol-26-acetate) (carijoside A, 1), was isolated from an octocoral identified as Carijoa sp. The structure of glycoside 1 was established by spectroscopic methods and by comparison with spectral data for the other known glycosides. Carijoside A (1) displayed significant inhibitory effects on superoxide anion generation and elastase release by human neutrophils and this compound exhibited moderate cytotoxicity toward DLD-1, P388D1, HL-60, and CCRF-CEM tumor cells. 相似文献
89.
Hyeok Ran Kwon Gyung Ja Choi Yong Ho Choi Kyoung Soo Jang Nack‐Do Sung Mun Seong Kang Yilseong Moon Seung Kyu Lee Jin‐Cheol Kim 《Pest management science》2010,66(6):634-639
BACKGROUND: Pine wilt disease (PWD) is very complex and has been reported to be caused by pine wood nematode, Bursaphelenchus xylophilus (Steiner & Buhrer) Nickle, and its accompanying bacteria. However, there is no report on the control of PWD by antibacterial agent. The present study was performed to investigate disease control efficacy of antibacterial agents against PWD. RESULTS: Among six antibacterial antibiotics tested, oxolinic acid (OA) showed the strongest antibacterial activity against five bacteria isolated from three strains of pine wood nematode. In in vivo assay, it effectively suppressed the development of PWD in three‐year‐old seedlings of Pinus densiflora Sieb. & Zucc.; it showed 71% control when injected at 3 mg per seedling. A mixture of OA and the nematicidal agent abamectin (Ab) showed higher disease control efficacy against PWD than either OA or Ab alone. In addition, OA alone and a mixture of OA and Ab also controlled PWD in approximately 20‐year‐old pine trees under field conditions. CONCLUSION: This is the first report on the suppression of PWD by OA. The result strongly indicates that PWD could be controlled by antibacterial antibiotic alone and a combination of antibacterial and nematicidal agents. Copyright © 2010 Society of Chemical Industry 相似文献
90.