• Analytical Science and Technology
• /
• v.25 no.6
• /
• pp.339-344
• /
• 2012

In this research, hydride generation in HPLC-ICPMS for the selenium speciation was investigated. Chemical and photochemical vapor generation techniques were compared for the effective generation of selenium vapour. $HBr/KBrO_3$ was used for the chemical reduction and a UV lamp was used for the photochemical reduction. It was found out that the photochemical reduction was more effective than the chemical reduction in all of selenium species studied. The optimum conditions for the generation of vapour are 0.4% KI, 2.5% $NaBH_4$, and 1.0 M HCl. The enhancement factor using a photochemical hydride generation was from 6.3 to 16.7 times for inorganic and organic selenium species.

• ALGAE
• /
• v.21 no.4
• /
• pp.445-452
• /
• 2006

The morphometry and distribution of the unarmoured dinoflagellates Brachidinium capitatum F.J.R. Taylor, Asterodinium gracile Sournia, Microceratium orstomii Sournia and the toxic species Karenia papilionacea Haywood et Steidinger have been investigated in open waters of the SE Pacific Ocean. The genus Microceratium Sournia is recorded for the first time since the initial description. These taxa showed a high morphological similarity and they may correspond to life stages of a highly versatile single species that is able to project body extensions. Karenia papilionacea showed the higher abundance in the surface waters of the more productive areas (the Marquesas Archipelago and the Perú-Chile Current). Brachidinium capitatum and K. papilionacea often co-occurred, predominating B. capitatum in offshore surface waters. Asterodinium gracile was recorded at the bottom of the euphotic zone (down to 210 m depth), with a shallower distribution in more productive areas. Intermediate specimens of Asterodinium-Brachidinium-Karenia, with variable disposition and size of the body extensions were illustrated.

• Animal Systematics, Evolution and Diversity
• /
• v.36 no.2
• /
• pp.182-184
• /
• 2020

Isaacsicalanus paucisetus Fleminger, 1983, a monotypic species of the family Spinocalanidae Vervoort, 1951, was first reported from a hydrothermal vent field in the East Pacific Rise off the mouth of the Gulf of California. The mitochondrial cytochrome oxidase I(mtCOI) DNA barcodes are considered a useful tool to assist traditional taxonomy and species discrimination in calanoid copepods. However, the mtCOI DNA barcodes of I. paucisetus have not been reported due to the species rarity and the difficulty of sampling. In this study, we firstly determined the mtCOI DNA barcodes of the I. paucisetus newly collected from a hydrothermal vent in the North Fiji Basin of the southwestern Pacific. All mtCOI DNA barcodes of I. paucisetus were identical and intraspecies variations of spinocalanid species were 0.0-3.0%. Interspecies and intergeneric variations were 13.4-25.2% and 16.7-24.1%, respectively. The DNA barcodes of I. paucisetus obtained in the present study would be helpful for understanding taxonomic relationships of widespread spinocalanid species.

• Animal Systematics, Evolution and Diversity
• /
• v.35 no.1
• /
• pp.30-32
• /
• 2019

The brachyuran crab Bythograeidae Williams, 1980 is common in hydrothermal vent fields worldwide and has recorded to sixteen species of six genera. In this study, we firstly determined the cytochrome c oxidase subunit 1 (CO1) DNA barcodes for the fifth species of Austinograea, A. hourdezi, from hydrothermal vent regions of the North Fiji Basin in southwestern Pacific Ocean. All CO1 DNA barcodes of A. hourdezi were identical. The interspecies variations of three bythograeid genera were 10.9-13.3% for Austinograea, 6.6-15.7% for Bythograea, and 9.7% for Gandalfus. These results would be helpful to understand taxonomy of brachyuran crabs living in hydrothermal vent fields using CO1 DNA barcodes.

• Journal of Species Research
• /
• v.1 no.2
• /
• pp.218-223
• /
• 2012

While preparing a floristic study of Korean hepatics, we discovered four unrecorded species collected from Mt. Geumo, Donggang river, Mt. Deokhang, and Mt. Naebyeon in Korea. Plagiochila shangaica Steph., Porella stephaniana (C. Massal.) S. Hatt., Porella chinensis (Steph.) S. Hatt., Solenostoma horikawanum (Amakawa) V$\acute{a}\check{n}$a, Hentschel & J. Heinrichs are reported for the first time in Korea here.

• Journal of the Korean Chemical Society
• /
• v.66 no.5
• /
• pp.341-348
• /
• 2022

In this work, radio frequency magnetron sputtering was used to deposit zinc selenide thin films on p-type silicon (100) wafers and glass substrates in a high vacuum chamber. Several surface characterization instruments were implemented to study the thin films. X-ray photoelectron spectroscopy results revealed that oxidized Zn bound to Se (Zn-Se) at 1022.7 ± 0.1 eV becomes the dominant oxidized species when Se concentration exceeds 70%. Scanning electron microscopy coupled with energy dispersive spectroscopy showed that incorporating Se in Zn thin films will lead to formation of ZnSe grains on the surface. Contact angle measurements indicated that ZnSe-60 exhibited the lowest total surface free energy value of 24.94 mN/m. Lastly, ultraviolet-visible spectrophotometry and ultraviolet photoelectron spectroscopy data evinced that the energy band gap gradually increases with increasing Se concentration with ZnSe-70 having the highest work function value of 4.91 eV.

• The Journal of the Society of Korean Medicine Diagnostics
• /
• v.17 no.3
• /
• pp.263-273
• /
• 2013

Objectives This study was designed to investigate the anti-inflammatory effect of extracts from Ligustrum obtusifolium S. fruits(LOF) in RAW 264.7 Macrophages stimulated with lipopolysaccharide(LPS). Methods We examined productions of nitric oxide(NO), reactive oxygen species(ROS), inducible isoforms of NO synthase(iNOS), cyclooxygenase-2(COX-2) to investigate the anti-inflammatory effect of LOF extracts. In addition, we measured generation of pro-inflammatory cytokines(TNF-${\alpha}$, IL-6). Results Cell viability showed that LOF extracts had no cytotoxicity in Raw 264.7 cells. The treatment with LOF extracts significantly decreased the generation of NO and pro-inflammatory cytokines(TNF-${\alpha}$, IL-6) in LPS-stimulated macrophage cells. Furthermore LOF extracts inhibited intracellular ROS generation dose dependently and reduced the expression of iNOS, COX-2 proteins. Conclusions These results showed that the LOF extracts had an anti-inflammatory effect on LPS-stimulated Raw 264.7 cells. These findings provide scientific support for the use of this Ligustrum obtusifolium S. for inflammatory-related diseases.

• Korean Journal of Environmental Agriculture
• /
• v.37 no.2
• /
• pp.146-149
• /
• 2018

BACKGROUND: Selenium is an essential element for all life forms but can be toxic above certain narrow levels. Prevalent forms of selenium in oxic environment are selenium oxyanions such as selenite and selenate, which may be contaminants in soils and water bodies. Bacterial reduction of more mobile selenium species (selenite or selenate) to less mobile elemental selenium may suggest a benign solution for alleviating toxicity and bioavailability of the selenium species. METHODS AND RESULTS: A facultative anaerobic bacterium, Citrobacter strain SE4-1 was isolated from the contaminated stream sediments and found to effectively reduce selenite to elemental selenium. Aqueous phase of selenite was analyzed by inductively couple plasma spectroscopy and the precipitated sphere-shaped elemental selenium was observed by transmission electron microscopy. CONCLUSION: The bacterial strain SE4-1 isolated in this study suggests a potential role in biogeochemical cycle of selenium by the selenite reduction in the stream environment, and potentials for biotechnological applications to reduceselenium concentrations in selenium-contaminated systems such as wastewater, soil, and groundwater.

• Journal of Practical Agriculture & Fisheries Research
• /
• v.6 no.1
• /
• pp.90-101
• /
• 2004

Se is essential for a number of enzymes that perform important metabolic functions necessary for good health. However, people in many countries do not appear to consume adequate amounts of Se to support the maximal expression of the selenoproteins and Se retention in the body of animals and humans is dependent on the ingested Se source such as organic and inorganic Se. Therefore, this review was discussed to explore metabolic characterization regarding intestinal absorption, bioavailability and selenoprotein synthesis according to animal species such as monogastrics including human beings and ruminants. Generally, organic Se provided to animals is more effective than inorganic Se in body retention for the animal owing to the difference of manner for intestinal absorption. But, Se absorption in ruminants depending on its chemical form still remained questioned by several microbial actions and feeding regimen in the rumen. And Se absorbed through small intestine is utilized for the synthesis of selenoproteins and/or retained as selenoamino acids in the body. Retained Se in the body may be recycled to synthesize selenoproteins as lacked of dietary Se. In conclusion, desirable forms of Se ingestion in the animal may be useful for Se fortification in animal products as well as well being for humans and animals.

• The Korea Journal of Herbology
• /
• v.25 no.4
• /
• pp.7-10
• /
• 2010

Objectives : The purpose of this study was to investigate the nodakenin and decursin contents in each fermented Angelicae gigantis Radix by 4 species of ferment strains. Methods : The strains of fermented Angelicae gigantis Radix were Lactobacillus plantarum(SE1), L. acidophilus(AC), Bacillus subtilis(B2) and B. licheniformis(BL2). The fermentative changes of nodakenin and decursin were analyzed using HPLC. Results : All of 4 species strains reduced nodakenin and decursin concentration in Angelicae gigantis Radix by fermentation. But fermentability were difference between strains. The nodakenin concentration of AC was lower than B2. The decursin concentrations of SE1 and AC were lower than B2 and BL2. Conclusions : 4 species of fermental strain were difference decomposable rate with nodakenin and decursin in fermented Angelicae gigantis Radix.