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311.
E. H. Kim P. Seguin J. E. Lee C. G. Yoon H.‐K. Song J.‐K. Ahn I.‐M. Chung 《Journal of Agronomy and Crop Science》2011,197(1):75-80
The gradual disruption of the ozone layer in the stratosphere has resulted in increased exposure of plants to ultraviolet‐B (UV‐B, 280–315 nm) radiation. UV‐B radiation is known to affect crop growth and quality negatively. A study was conducted to determine the impact of elevated UV‐B radiation levels on the isoflavones and phenolic compound concentrations of seven soybean varieties. UV‐B radiation significantly reduced the concentration of most isoflavones and phenolic compounds in soybean seeds. Exposure to elevated UV‐B levels overall resulted in 35 % reduction in total isoflavones and 31 % in phenolic compounds concentrations. The effect on individual isoflavones and phenolic compounds depended on the compound and variety, but UV‐B overwhelmingly reduced concentrations. This study suggests that increased UV‐B radiation negatively impacted soybean quality by reducing the concentration of compounds that have health‐beneficial properties. 相似文献
312.
Eun-A Kim Eui-Jeong Han Junseong Kim Ilekuttige Priyan Shanura Fernando Jae-Young Oh Kil-Nam Kim Ginnae Ahn Soo-Jin Heo 《Marine drugs》2022,20(2)
In this study, we investigated the anti-allergic effects of 3,4-dihydroxybenzaldehyde (DHB) isolated from the marine red alga, Polysiphonia morrowii, in mouse bone-marrow-derived cultured mast cells (BMCMCs) and passive cutaneous anaphylaxis (PCA) in anti-dinitrophenyl (DNP) immunoglobulin E (IgE)-sensitized mice. DHB inhibited IgE/bovine serum albumin (BSA)-induced BMCMCs degranulation by reducing the release of β-hexosaminidase without inducing cytotoxicity. Further, DHB dose-dependently decreased the IgE binding and high-affinity IgE receptor (FcεRI) expression and FcεRI-IgE binding on the surface of BMCMCs. Moreover, DHB suppressed the secretion and/or the expression of the allergic cytokines, interleukin (IL)-4, IL-5, IL-6, IL-13, and tumor necrosis factor (TNF)-α, and the chemokine, thymus activation-regulated chemokine (TARC), by regulating the phosphorylation of IκBα and the translocation of cytoplasmic NF-κB into the nucleus. Furthermore, DHB attenuated the passive cutaneous anaphylactic (PCA) reaction reducing the exuded Evans blue amount in the mouse ear stimulated by IgE/BSA. These results suggest that DHB is a potential therapeutic candidate for the prevention and treatment of type I allergic disorders. 相似文献
313.
Jeoung-Hwa Shin Yun Gyong Ahn Ju-Hee Jung Sun-Hee Woo Hag-Hyun Kim Shela Gorinstein Hee-Ock Boo 《Plant foods for human nutrition (Dordrecht, Netherlands)》2017,72(1):13-19
Platycodon grandiflorum (PG), a species of herbaceous flowering perennial plant of the family Campanulaceae, has been used as a traditional oriental medicine for bronchitis, asthma, pulmonary tuberculosis, diabetes, hepatic fibrosis, bone disorders and many others similar diseases and as a food supplement. For the primary profiling of PG gas chromatography coupled with high resolution – time of flight mass spectrometry (GC/HR-TOF MS) was used as an analytical tool. A comparison of optimal extraction of metabolites was carried out with a number of solvents [hexane, methylene chloride, methanol, ethanol, methanol: ethanol (70:30, v:v)]. In extracts with methanol: ethanol (70:30 v:v) were detected higher amounts of metabolites than with other solvents. Principal component analysis (PCA) and partial least-squares discriminant analysis (PLS-DA) plots showed significant differences between the diploid and tetraploid metabolite profiles. Extracts of tetraploid showed higher amounts of amino acids, while extracts of diploid contained more organic acids and sugars. 相似文献
314.
Tu Thanh Dung Freddy Haesebrouck Patrick Sorgeloos Nguyen Ahn Tuan Frank Pasmans Annemieke Smet Annemie Decostere 《Aquaculture (Amsterdam, Netherlands)》2009,295(3-4):157-159
Eight tetracycline resistant Edwardsiella ictaluri isolates obtained from diseased freshwater catfish (Pangasianodon hypophthalmus) in Vietnam, and showing different resistance phenotypes to other antimicrobial agents, were studied. The tet genes were determined using PCR. Conjugation experiments were performed to assess transferability of the tetracycline resistance determinant and the size and incompatibility group (Inc) of each tet-carrying plasmid were determined. PCR and sequencing were used for characterization of the co-transferred resistance genes. A tetA gene was demonstrated in the E. ictaluri isolates and for all of them, Escherichia coli transconjugants were obtained. All transconjugants contained high-molecular weight tetA-carrying plasmids (~ 140 kb) belonging to the incK group, as was shown with the PCR-based replicon typing method. The strA–strB, dhfr1 and sul 2 genes were detected on the tetA-carrying plasmids of the transconjugants showing resistance to streptomycin, trimethoprim and sulfonamides, respectively. The dhfr1 gene was found to be located in a class 1 integron as determined by PCR and sequencing. Interestingly, the 3′ CS region of class 1 integrons was not detected by PCR. This study shows the presence of incK plasmid-mediated tetracycline resistance among E. ictaluri isolates from diseased freshwater catfish in Vietnam. 相似文献
315.
Cardiovascular disease represents a leading cause of mortality and is often characterized by the emergence of endothelial dysfunction (ED), a physiologic condition that takes place in the early progress of atherosclerosis. In this study, two cytoprotective peptides derived from blue mussel chymotrypsin hydrolysates with the sequence of EPTF and FTVN were purified and identified. Molecular mechanisms underlying the cytoprotective effects against oxidative stress which lead to human umbilical vein endothelial cells (HUVEC) injury were investigated. The results showed that pretreatment of EPTF, FTVN and their combination (1:1) in 0.1 mg/mL significantly reduced HUVEC death due to H2O2 exposure. The cytoprotective mechanism of these peptides involves an improvement in the cellular antioxidant defense system, as indicated by the suppression of the intracellular ROS generation through upregulation of the cytoprotective enzyme heme oxygenase-1. In addition, H2O2 exposure triggers HUVEC damage through the apoptosis process, as evidenced by increased cytochrome C release, Bax protein expression, and the elevated amount of activated caspase-3, however in HUVEC pretreated with peptides and their combination, the presence of those apoptotic stimuli was significantly decreased. Each peptide showed similar cytoprotective effect but no synergistic effect. Taken together, these peptides may be especially important in protecting against oxidative stress-mediated ED. 相似文献
316.
Joo Sung Ahn Jung-Hyun Kim Jae-Gon Kim Yungoo Song Hi-Soo Moon 《Water, air, and soil pollution》2003,150(1-4):23-42
The geochemical behavior of metals, including Fe, Mn, Pb and Zn, in contaminated paddy soils was investigated during the cultivation of rice crops through laboratory microcosm experiments. From the two paddy fields contaminated by mine tailings, Siheung and Deokeum in Korea, paddy soils were collected and analyzed for their geochemical characteristics. The Siheung paddy soil showed higher levels of heavy metals, whereas the higher potential for the release of metals was anticipated due to the extremely acidic conditions at Deokeum. In microcosm experiments of flooded paddy soils over 18 weeks, Fe and Mn were released in subsurface pore waters by reductive dissolution, and Pb and Zn were dissolved in high amounts at the surface by oxidation of sulfides. Although amorphous Fe oxide-rich layers were formed at the surface of both paddy soils, the release of Pb and Zn were controlled at the surface by these layers only under slightly alkaline conditions at Siheung. Lead and Zn were associated with the reducible and carbonate fractions at the surface paddy soil of Siheung from the sequential extraction on core samples collected during the flooded period. In the acidic conditions at Deokeum, Pb and Zn were continuously released until the late stage of flooding. A great increase in the exchangeable fraction of metals was observed after the soils had drained. The bioavailability of metals for rice crops would be high under acidic conditions at Deokeum, despite the lower levels of heavy metal contamination. 相似文献
317.
S.-J. Kwon W.-G. Ha H.-G. Hwang S.-J. Yang H.-C. Choi H.-P. Moon S.-N. Ahn 《Plant Breeding》2002,121(6):487-492
Improving grain yield and quality of ‘Tongil’‐type rice (indica/japonica) continues to be a major breeding objective in Korea. In this study, genetic divergence among 13‘Tongil’‐type rice cultivars was evaluated and the relationship between genetic distance and hybrid performance in all possible nonreciprocal crosses between them assessed. The 78 F1 hybrids together with the 13 parents were evaluated for eight traits of agronomic importance, including yield, in a replicated field trial. The 13 parents were examined for DNA polymorphism using 71 micro‐satellite or simple sequence repeats and 46 random decamer oligonucleotide primers. A total of 319 polymorphic variants were generated and, based on the polymorphism data, genetic distances (GDs) ranged from 0.021 to 0.437. Cluster analysis based on GDs revealed associations among cultivars which was in agreement with the pedigree data. Heterosis was observed in hybrids for most of the traits, and yield exhibited the highest heterosis among the eight traits examined. The correlation values of GDs with F1 performance were mostly nonsignificant, except for yield, culm length and spikelets per panicle. The correlations of GDs with midparent and better‐parent heterosis were not significant enough to be of predictive value. These results indicate that GDs based on the microsatellite and random amplified polymorphic DNA (RAPD) markers may not be useful for predicting heterotic combinations in ‘Tongil’‐type rice and support the idea that the level of correlation between hybrid performance and genetic divergence is dependent on the germplasm used. 相似文献
318.
Young-Joon Ahn Jum-Rae Cho Young-Joon Kim Jai-Ki Yoo Jeang-Oon Lee 《Pest management science》1997,51(4):455-461
The toxicity of herbicides widely used in apple orchards to the two-spotted spider mite (Tetranychus urticae) was evaluated in laboratory and field studies. In a laboratory study with susceptible T. urticae, glufosinate-ammonium was highly effective against larvae, protonymphs and adults, but non-toxic to eggs. Its efficacy was much greater than that of the commonly used acaricide azocyclotin. The immatures died within 24 h after treatment, suggesting that the nymphicidal action may be attributable to a direct effect rather than an inhibitory action of chitin synthesis. Glufosinate-ammonium showed a positive temperature coefficient of toxicity against T. urticae adults at six temperatures from 10 to 32°C, being more toxic at higher temperatures. Very low levels of resistance to the herbicide were observed in the seven field-collected T. urticae populations resistant to various acaricides. Treatment with glufosinate-ammonium did not cause a repellent response from either adults or immature stages of T. urticae. Paraquat dichloride and glyphosate were ineffective against all stages of T. urticae. In a field study of a population of T. urticae, glufosinate-ammonium when sprayed to weeds caused significant decrease in T. urticae population densities in apple trees for nine weeks after treatment, as compared with the control. Thereafter, a single application of standard acaricides to apple foliage greatly reduced population densities, although there was no difference in the densities between the glufosinate-ammonium-treated and control plots. Based upon laboratory and field data, two single treatments with glufosinate-ammonium to weeds in May and a selective acaricide to apple trees in July may be used to prevent damage by T. urticae. ©1997 SCI 相似文献
319.
Jung Eun Seol Sang Woo Ahn Bomin Seol Hyeong Rok Yun Nammi Park Hyoung Kyu Kim Elena A. Vasileva Natalia P. Mishchenko Sergey A. Fedoreyev Valentin A. Stonik Jin Han 《Marine drugs》2021,19(10)
Echinochrome A (Ech A, 7-ethyl-2,3,5,6,8-pentahydroxy-1,4-naphthoquinone) has been known to exhibit anti-oxidative and anti-inflammatory effects. However, no study has been carried out on the efficacy of Ech A against skin photoaging; this process is largely mediated by oxidative stress. Six-week-old male SKH-1 hairless mice (n = 36) were divided into five groups. Except for a group that were not treated (n = 4), all mice underwent ultraviolet-B (UVB) exposure for 8 weeks while applying phosphate-buffered saline or Ech A through intraperitoneal injection. UVB impaired skin barrier function, showing increased transepidermal water loss and decreased stratum corneum hydration. UVB induced dermal collagen degeneration and mast cell infiltration. Ech A injection was found to significantly lower transepidermal water loss while attenuating tissue inflammatory changes and collagen degeneration compared to the control. Furthermore, Ech A was found to decrease the relative expression of matrix metalloproteinase, tryptase, and chymase. Taken together, these results suggest that Ech A protects against UVB-induced photoaging in both functional and histologic aspects, causing a lowering of collagen degradation and inflammatory cell infiltration. 相似文献
320.
D. P. Nagahawatta Hyun-Soo Kim Young-Heun Jee Thilina U. Jayawardena Ginnae Ahn Jin Namgung In-Kyu Yeo K. K. Asanka Sanjeewa You-Jin Jeon 《Marine drugs》2022,20(1)
Sargassum horneri is an invasive brown seaweed that grows along the shallow coastal areas of the Korean peninsula, which are potentially harmful to fisheries and natural habitats in the areas where it is accumulated. Therefore, the author attempted to evaluate the anti-inflammatory mechanism of Sargachromenol isolated from S. horneri against particulate matter (PM)-stimulated RAW 264.7 macrophages. PM is a potent inducer of respiratory diseases such as lung dysfunctions and cancers. In the present study, the anti-inflammatory properties of Sargachromenol were validated using enzyme-linked immunosorbent assay (ELISA), Western blots, and RT-qPCR experiments. According to the results, Sargachromenol significantly downregulated the PM-induced proinflammatory cytokines, Prostaglandin E2 (PGE2), and Nitric Oxide (NO) secretion via blocking downstream activation of Toll-like receptor (TLR)-mediated nuclear factor kappa B (NF-κB) and MAPKs phosphorylation. Thus, Sargachromenol is a potential candidate for innovation in various fields including pharmaceuticals, cosmeceuticals, and functional food. 相似文献