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71.
Ji Hyung Kim Sun Young Hwang Jee Soo Son Jee Eun Han Jin Woo Jun Sang Phil Shin Casiano Choresca Jr Yun Jaie Choi Yong Ho Park Se Chang Park 《Journal of veterinary science (Suw?n-si, Korea)》2011,12(1):41-48
The antibiotic resistance of 16 Aeromonas (A.) salmonicida strains isolated from diseased fish and environmental samples in Korea from 2006 to 2009 were investigated in this study. Tetracycline or quinolone resistance was observed in eight and 16 of the isolates, respectively, based on the measured minimal inhibitory concentrations. Among the tetracycline-resistant strains, seven of the isolates harbored tetA gene and one isolate harbored tetE gene. Additionally, quinolone-resistance determining regions (QRDRs) consisting of the gyrA and parC genes were amplified and sequenced. Among the quinolone-resistant A. salmonicida strains, 15 harbored point mutations in the gyrA codon 83 which were responsible for the corresponding amino acid substitutions of Ser83→Arg83 or Ser83→Asn83. We detected no point mutations in other QRDRs, such as gyrA codons 87 and 92, and parC codons 80 and 84. Genetic similarity was assessed via pulsed-field gel electrophoresis, and the results indicated high clonality among the Korean antibiotic-resistant strains of A. salmonicida. 相似文献
72.
Min‐Jung GU Md. Jahangir ALAM Seon‐Ho KIM Che‐Ok JEON Moon‐Baek CHANG Young‐Kyoon OH Sang‐Cheol LEE Sang‐Suk LEE 《Animal Science Journal》2011,82(5):663-672
Molecular diversity of methanogens in the rumen of Korean black goats was investigated with 16S rRNA gene clone libraries using methanogen‐specific primers. The libraries were composed of rumen fluid‐associated methanogens (FAM) and rumen particle‐associated methanogens (PAM) from rumen‐fistulated Korean black goats. Among the 141 clones of the FAM library, the sequences were mostly related to two phyla, the Methanobacteriaceae family (77.3%) and the Thermoplasmatales family (22.7%); and among the 68 clones of the PAM library, sequences were also mainly clustered in the two phyla, the Thermoplasmatales family (63.24%) and the Methanobacteriaceae family (35.29%). Most of the sequenced clones in the two libraries were closely related to uncultured methanogenic archaeon. Quantitative real‐time PCR revealed that PAM (8.97 log 10) had significantly higher (P < 0.01) density of methanogens by the methanogenic 16S rRNA gene copies than FAM (7.57 log 10). The two clone libraries also showed difference in Shannon index (FAM library 1.70 and PAM library 1.59) and Chao 1 estimator (FAM library 18 and PAM library 17 operational taxonomic units). Apparent differences found in the microbial community from the two 16S rRNA gene libraries could be a result of such factors as the chemical and physical nature of the target material surface, types or component of diets, the interaction between the methanogens and other microbes, and age of the experimental goats. 相似文献
73.
Flavonol glycosides and novel iridoid glycoside from the leaves of Morinda citrifolia 总被引:5,自引:0,他引:5
Sang S Cheng X Zhu N Stark RE Badmaev V Ghai G Rosen RT Ho CT 《Journal of agricultural and food chemistry》2001,49(9):4478-4481
One new iridoid glycoside and five known flavonol glycosides have been isolated from the leaves of Morinda citrifolia. The new iridoid exists as an epimeric mixture in solution. Complete assignments of the proton and carbon chemical shifts for the individual epimers were accomplished on the basis of high-resolution 1D and 2D NMR data. Their antioxidative activities were measured. All of these compounds showed DPPH free radical scavenging activity at the concentration of 30 microM. 相似文献
74.
New prenylated benzoic acid and other constituents from almond hulls (Prunus amygdalus Batsch). 总被引:2,自引:0,他引:2
Shengmin Sang Karen Lapsley Robert T Rosen Chi-Tang Ho 《Journal of agricultural and food chemistry》2002,50(3):607-609
One new prenylated benzoic acid derivative, 3-prenyl-4-O-beta-D-glucopyranosyloxy-4-hydroxylbenzoic acid, and three known constituents, catechin, protocatechuic acid, and ursolic acid, have been isolated from the hulls of almond (Prunus amygdalus). Complete assignments of the proton and carbon chemical shifts for the new prenylated benzoic acid derivative were accomplished on the basis of high-resolution 1D and 2D nuclear magnetic resonance data. All of these compounds except ursolic acid are being reported from almond hulls (P. amygdalus) for the first time. 相似文献
75.
Sang S Zou M Xia Z Lao A Chen Z Ho CT 《Journal of agricultural and food chemistry》2001,49(10):4780-4783
Three new spirostanol saponins have been isolated from the seeds of Allium tuberosum. On the basis of acid hydrolysis and comprehensive spectroscopic analysis, their structures were established as tuberoside J, (25R)-5alpha-spirostan-2alpha,3beta,27-triol 3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranoside; tuberoside K, (25R)-5alpha-spirostan-2alpha,3beta,27-triol 3-O-alpha-L-rhamnopyranosyl-(1-->2)-[alpha-L-rhamnopyranosyl-(1-->4)]-beta-D-glucopyranoside; and tuberoside L, 27-O-beta-D-glucopyranosyl-(25R)-5alpha-spirostan-2alpha,3beta,27-triol 3-O-alpha-D-rhamnopyranosyl-(1-->2)-[alpha-L-rhamnopyranosyl-(1-->4)]-beta-D-glucopyranoside. 相似文献
76.
Four new steroidal saponins from the seeds of Allium tuberosum 总被引:3,自引:0,他引:3
Four new steroidal saponins, 26-O-beta-D-glucopyranosyl-(25S,20R)-20-O-methyl-5alpha-furost-22(23)-en-2alpha,3beta,20,26-tetraol 3-O-alpha-L-rhamnopyranosyl-(1-->2)-[alpha-L-rhamnopyranosyl-(1-->4)]-beta-D-glucopyranoside (1); 26-O-beta-D-glucopyranosyl-(25S,20R)-5alpha-furost-22(23)-en-2alpha,3beta,20,26-tetraol 3-O-alpha-L-rhamnopyranosyl-(1-->2)-[alpha-L- rhamnopyranosyl-(1-->4)]-beta-D-glucopyranoside (2); 26-O-beta-D-glucopyranosyl-(25S,20S)-5alpha-furost-22(23)-en-2alpha,3beta,20,26-tetraol 3-O-alpha-L-rhamnopyranosyl-(1-->2)-[alpha-L- rhamnopyranosyl-(1-->4)]-beta-D-glucopyranoside (3); and 26-O-beta-D-glucopyranosyl-(25S,20S)-5alpha-furost-22(23)-en-3beta,20,26-triol 3-O-alpha-L-rhamnopyranosyl-(1-->2)-[alpha-L-rhamnopyranosyl-(1-->4)]-beta-D-glucopyranoside (4), have been isolated from the seeds of Allium tuberosum. Their structures were established by spectroscopic studies such as MS, IR, NMR, and 2D-NMR and the results of acid hydrolysis and named tuberosides F, G, H, and I, respectively. 相似文献
77.
Sang S Kikuzaki H Lapsley K Rosen RT Nakatani N Ho CT 《Journal of agricultural and food chemistry》2002,50(16):4709-4712
One sphingolipid, 1-O-beta-D-glucopyranosyl-(2S,3R,4E,8Z)-2-[(2R)-2-hydroxyhexadecanoylamino]-4,8-octadecadiene-1,3-diol, and four other constituents, beta-sitosterol, daucosterol, uridine, and adenosine, have been isolated from the nuts of almond (Prunus amygdalus). Complete assignments of the proton and carbon chemical shifts for the sphingolipid were accomplished on the basis of high-resolution 1D and 2D NMR data. All of these compounds are being reported from almond nuts (P. amygdalus)for the first time. 相似文献
78.
79.
甘蓝型油菜种子萌发期耐铝毒特性综合评价及其种质筛选 总被引:1,自引:0,他引:1
种子萌发是油菜植株形态建成的重要阶段,铝毒是酸性土壤中影响其种子萌发的主要因素之一,因此筛选出种子萌发过程中耐铝毒种质对油菜生产及研究具有重要意义。本研究利用5份甘蓝型油菜品种(系)筛选出油菜萌发期耐铝毒种质资源处理的适宜胁迫浓度为90μg mL~(-1)。并以该浓度处理148份甘蓝型油菜品种(系)种子,于萌发期测定其发芽势、发芽率、鲜重、干重、根长和芽长等指标,通过铝毒胁迫耐性综合评价值(A值)、平均隶属函数值(ASF值)、对铝毒加权耐性系数(WAC值)、相关性、频数、主成分、灰色关联度、聚类和逐步回归分析等鉴定萌发期耐铝性,建立萌发期对铝毒耐性综合评价模型并筛选出适宜的评价鉴定指标。结果表明, 148份甘蓝型油菜的萌发期各指标在品种(系)间存在显著差异;筛选出萌发期耐铝毒甘蓝型油菜品种(系) 01188、WH-20、A109、甲预31棚等。根据灰色关联度及回归分析结果认为,在油菜萌发期测定其根长、芽长、鲜重、发芽率和发芽势,通过回归方程估算其A值,可以初步判断甘蓝型油菜种质的耐铝毒特性。 相似文献
80.
Soybean seed includes various bioactive substances. Also, they contain a variety of antinutritional factors including lipoxygenase, Kunitz trypsin inhibitor (KTI), lectin, and 7S α' subunit proteins. The genetic removal of these proteins will improve the nutritional value of soybean seed. The objective of this research was to breed new soybean with tetra recessive alleles (lox1lox2lox3/lox1lox2lox3‐ti/ti‐le/le‐cgy1/cgy1) for lipoxygenase, KTI, lectin, and 7S α' subunit proteins. Seven parents were used to breed tetra null strain. SDS‐PAGE and Western blot analysis were used to determine the presence or absence of lipoxygenase, 7S α' subunit, KTI, and lectin proteins in mature seed. Tetra null soybean line has a purple flower, determinate growth habit, tan pod, and yellow seed coat colour. Stem height of the breeding line was 62.3 cm. The 100‐seed weight of the breeding line was 27.1 g and yield (t/ha) was 2.84. This is the first soybean strain with lox1lox2lox3/lox1lox2lox3‐ti/ti‐le/le‐cgy1/cgy1 genotype (absence of lipoxygenase, KTI, lectin, and 7S α' subunit proteins). 相似文献