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1.
Ng  Shing-Lai  Joung  Shoou-Jeng 《Fisheries Science》2022,88(6):703-720

Small-bodied sharks are recognized as mesopredators on different communities in a large variety of habitats, thus linking the trophic levels in the marine ecosystem. Dietary analysis on these species can provide insight into the trophic relationships in food webs. Our study analyzed the diet composition of Galeus sauteri, an abundant small shark inhabiting neritic shelf waters at depths between 60 and 200 m. For this purpose, a stomach content analysis was realized in 678 specimens collected by bottom trawlers off northeastern Taiwan from September 2018 to August 2019. The two most commonly consumed preys were teleosts (prey-specific index of relative importance, %PSIRI?=?51.94) and crustaceans (%PSIRI?=?30.08).The results for the Levin’s index (Ba?=?0.06) and graphical analysis based on the Costello method revealed a high degree of specialization on lanternfishes and other teleosts. The mean trophic position was 4.29. Feeding habits differed significantly in relation to maturity condition and between seasons. Our result showed that G. sauteri is a primary piscivorous shark that preys mainly on lanternfishes and other teleosts, and feeds opportunistically on crustaceans and cephalopods.

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2.
6[8'(Z)-pentadecenyl]salicylic acid, otherwise known as anacardic acid (C15:1), inhibited the linoleic acid peroxidation catalyzed by soybean lipoxygenase-1 (EC 1.13.11.12, type 1) with an IC50 of 6.8 microM. The inhibition of the enzyme by anacardic acid (C15:1) is a slow and reversible reaction without residual activity. The inhibition kinetics analyzed by Dixon plots indicates that anacardic acid (C15:1) is a competitive inhibitor and the inhibition constant, KI, was obtained as 2.8 microM. Although anacardic acid (C15:1) inhibited the linoleic acid peroxidation without being oxidized, 6[8'(Z),11'(Z)-pentadecadienyl]salicylic acid, otherwise known as anacardic acid (C15:2), was dioxygenated at low concentrations as a substrate. In addition, anacardic acid (C15:2) was also found to exhibit time-dependent inhibition of lipoxygenase-1. The alk(en)yl side chain of anacardic acids is essential to elicit the inhibitory activity. However, the hydrophobic interaction alone is not enough because cardanol (C15:1), which possesses the same side chain as anacardic acid (C15:1), acted neither as a substrate nor as an inhibitor.  相似文献   
3.
A population of hybrids between Arisaema triphyllum subsp. stewardsonii and A. dracontium was investigated using molecular markers to document the hybrid origin. Total genomic DNA was extracted from A. triphyllum, A. dracontium, and the hybrids, and subjected to sequence analysis of various regions of intergenic spacer and genes of chloroplast or intergenic spacer and genes of nuclear ribosome for single nucleotide polymorphisms (SNPs). Clustering was performed using the unweighted pair group method with averages (UPGMA) tested by bootstrap (BS). Hybrid origin could not be easily confirmed in some regions. However, dendrograms constructed with a combined sequence analysis of A. triphyllum 26S ribosomal RNA gene [sequence identification (SI) 467] plus A. tortuosum phytochrome C-like (phyC) gene (SI 468) were very similar to dendrograms constructed from sequences of all regions. This suggests that selecting SI 467 and SI 468 would be practical to identify hybrid origins involving two parental species. Clustering of hybrids together with the female parent in most target regions suggests that, in Arisaema, cpDNA is considered maternally inherited.  相似文献   
4.
Lipoxygenase inhibitory activity of octyl gallate   总被引:2,自引:0,他引:2  
Octyl gallate inhibited soybean lipoxygenase-1 (EC 1.13.11.12, type I) with an IC(50) of 1.3 microM. The inhibition of the enzyme by octyl gallate is a slow and reversible reaction without residual activity. The inhibition kinetics analyzed by Lineweaver-Burk plots indicates that octyl gallate is a competitive inhibitor, and the inhibition constant, K(I), was obtained as 0.54 microM. One molecule of octyl gallate scavenged six molecules of 1,1-diphenyl-2-picrylhydrazyl and inhibited autoxidative lipid peroxidation. In addition, octyl gallate was effective in preventing lipid peroxidation.  相似文献   
5.
The ionic composition of total suspended particulate (TSP) and fine (PM2.5) fractions was investigated from an 1,100 site in the middle of Mt. Halla in Jeju Island, Korea from March to November 2006. The sum concentrations of cation and anion species in TSP fraction were 205 ± 170 and 183 ± 164 neq m?3, respectively, while those for PM2.5 as 118 ± 129 and 88.5 ± 89.3 neq m?3, respectively. In TSP, the concentration of the major ions changed in the order of SO4 2? > NH4 + > Ca2+ > Na+ > NO3 ? > Mg2+ > K+ > Cl?, while its PM2.5 counterpart as NH4 + > SO4 2? > Ca2+ > NO3 ? > Na+ > Mg2+ > K+ > Cl?. Inspection of the temporal variabilities of ionic components indicated that most ions peaked in spring or fall months. The back trajectory analysis showed that the atmospheric composition of the major ionic species was affected fairly sensitively by long-range transport from China under the favorable meteorological conditions. In contrast, the lowest ionic concentration levels were seen most abundantly, when air masses passed from South Sea. Hence, the analysis of ionic concentration data suggests that their distributions are controlled by the combined effects of various source processes including the most prominent Chinese origin and the meteorological condition favorable for such transport.  相似文献   
6.
This study assessed the altitudinal variations in the anthocyanin and isoflavone contents of six black seed coated soybean [Glycine max (L.) Merrill] cultivars. The black soybean cultivars Heugcheong, Seonheuk, Geomjeong 1, Geomjeong 2, Cheongja 2, and Cheongja 3 were planted at Milyang (12 m above mean sea level — low altitude) and Muju (600 m — high altitude), Korea on 10 June 2005 and 2006. The total anthocyanin and isoflavone contents and individual components were investigated by reverse-phase high performance liquid chromatography (HPLC). All black soybean cultivars cultivated in high altitude possessed significantly higher total anthocyanin (p < 0.01) and isoflavone (p < 0.01) contents than those grown in low altitude. For anthocyanin composition, cyanidin-3-O-glucoside, cyanidin-3-O-galactoside, and peonidin-3-O-glucoside contents were significantly higher while delphinidin-3-O-glucoside contents was significantly lower at high altitude. The composition of individual isoflavones, 6″-O-malonyldaidzin, and 6″-O-malonylgenistin contents significantly increased at high altitude.  相似文献   
7.
The sperm‐mediated gene transfer method is applicable to transgenesis in many species that use spermatozoa for reproduction recently, which has been shown various results. In the current study, we show that transgenic porcine embryos can be efficiently produced by employing a simple transfection method that uses magnetic nanoparticles (MNPs). The complexes formed between plasmid DNA and MNPs were bounded on ejaculated boar spermatozoa at a higher efficiency compared to methods using DNA alone or lipofection. Using confocal microscopy, rhodamine fluorophore‐labelled MNPs were detected on external surfaces of the spermatozoa membrane, which were bounded on zona pellucida of in vitro maturated oocyte during in vitro fertilization. Electron microscopy revealed that clusters of MNPs were detected in inside of plasma membrane and nucleus of the spermatozoa head. Additionally, we found that magnetofected boar spermatozoa could be fertilized with oocytes in vitro and that the resulting gene of green fluorescent protein was detected in fertilized eggs by genomic PCR analysis. Taken together, these results suggest that MNPs can be used to efficiently introduce a transgene into embryo via spermatozoa.  相似文献   
8.
1 亲本来源辽单 2 7号 (原名辽 940 4 )为辽宁省农业科学院作物研究所以自选系辽 2 30 9为母本 ,引入系丹340为父本杂交组配而成。辽 2 30 9自选系是 1 990年以美国先锋杂交种7861 3(op)为基础材料连续自交多代选择育成。辽 2 30 9一般配合力高 ,高抗大、小斑病和丝黑穗病 ,抗病毒病和茎基腐病 ,秆硬抗倒 ,株形紧凑 ,活秆成熟 ,产量高。2 辽单 2 7号选育经过1 992年冬在海南岛测配时用丹 340 (是当时测验种之一 )配制成辽 2 30 9×丹 340杂交组合。1 993~ 1 994年进行院内品比试验。 1 995年参加辽宁省区域试验预备试验 ,1 996~ 1 997…  相似文献   
9.
This study was initiated to attempt clarify the identities of taxa referred to as Prunus yedoensis that grows under natural environments in Jeju, Korea and of Yoshino cherry hybrids of cultivated origin (also recorded as P. × yedoensis) in Japan, and to understand the difference between these two taxa. P. yedoensis and other species collected from natural habitats from Jeju, Korea and cultivated materials of Yoshino cherries from Tokyo and Washington, DC, were analyzed with inter-simple sequence repeat (ISSR) markers, and sequence analysis of two chloroplast DNA (cpDNA) genes, rpl16 and trnL-trnF spacer. Depending on the source of Yoshino cherry, accessions show variations with ISSR and cpDNA. Accessions belonging to each of P. serrulata var. spontanea, P. serrulata var. pubescens, and P. sargentii were grouped closely to P. yedoensis and Yoshino cherry accessions. However, two Yoshino cherry accessions that include ‘Akebono’ showed the same rpl16 haplotype of A and A at the position of 113 and 206, respectively, which were found in 4 out of 16 P. yedoensis accessions. Twelve accessions of P. yedoensis and 11 other Yoshino cherries showed rpl16 haplotype of T and A at these positions. P. yedoensis native to Korea can be considered different from Yoshino cherry of hybrid origin from Japan based on ISSR markers and rpl16 haplotypes. Therefore, it may be concluded that the Korean taxon currently referred to as P. yedoensis can be considered indigenous and sufficiently distinct to warrant recognition as a distinct entity.  相似文献   
10.
The antifungal activity of ethylenediaminetetraacetic acid (EDTA) against Saccharomyces cerevisiae was significantly affected by various conditions such as inoculum size, pH, and metal ions (Mg(2+), Ca(2+)). EDTA was found to be effective against this yeast at the inoculum size of 10(5) colony forming units (CFU)/mL with the minimum inhibitory concentration of 400 mug/mL and the minimum fungicidal concentration of 6400 mug/mL, but it was not effective at 10(7) CFU/mL up to 6400 mug/mL. The fungicidal activity of EDTA against S. cerevisiae was significantly enhanced in combination with polygodial. Isobolograms, fractional inhibitory concentration, and fractional fungicidal concentration indices were used for evaluating the interaction between combined compounds. This synergistic effect is likely due to polygodial's destructive action on the cellular membrane, which facilitates the transmembrane transport of foreign compounds (EDTA) into yeast cells. Once inside the cells, EDTA forms chelation with divalent metals such as Mg(2+) and Ca(2+), which are required by various essential enzymes.  相似文献   
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