• Korean Journal of Ichthyology
• /
• v.24 no.4
• /
• pp.247-252
• /
• 2012

Structure on the feeding organs in two Korean ricefishes, Oryzias latipes and O. sinensis, was examined in the jaws and the teeth. In the jaw, O. latipes has a dent on the dorsal edge of distal arm of premaxilla (vs. straight in O. sinensis) and a alveolar arm of premaxilla running in straight line with distal arm of premaxilla (vs. ventra line in O. sinensis). O. latipes has also a dent on the posterior edge of dentary which is connected to coronoid process of dentary (vs. straight in O. sinensis). Large teeth developing only in the male, which is sexual dimorphism, developed into outside direction of the mandible in O. latipes (vs. dorsal direction in O. sinensis). In the teeth forms, O. latipes has two types (conical type and arrowhead type), whereas O. sinensis has only one type (conical type). Through this study, we confirmed that two Korean ricefishes show distinctive characteristics in the structure of the feeding organs.

• Journal of Ecology and Environment
• /
• v.36 no.3
• /
• pp.159-166
• /
• 2013

Oryzias latipes and Oryzias sinensis are indigenous species found in Japan, China, and other East Asian countries, including Korea. Based on morphological differences, the species have been classified distinctly. However, the range of morphological characters such as the number of gill rakers, vertebrae, and spots on the lateral body overlaps and is too vague for clear identification, so their classification based on their morphological characteristics remains uncertain. In this study, the mitochondrial cytochrome oxidase subunit I (COI) gene, which is used for DNA barcoding, was applied to clarify interspecific variation of O. latipes and O. sinensis. Intraspecific genetic diversity was calculated to identify correlations with geographic distributions. We studied two species collected from 55 locations in Korea. All individuals carried a 679-base pair gene without deletion or insertion. Between species, 525 base pairs of the gene were shared. The Kimura two parameter (K2P) distance of O. latipes and O. sinensis was 0.41% and 1.39%, respectively. Mean divergence within genera was 23.5%. Therefore, the species were clearly different. The distance between O. latipes and O. sinensis was 14.0%, which is the closest within genera. Interestingly O. latipes from the Japanese and Korean group represented 16.5% distant. These results were derived from geohistorical and anthropogenic environmental factors. The O. latipes haplotypes were joined in only one group, but O. sinensis was divided into two groups, one is found in the Han River and upper Geum River watershed; the other is found in the remaining South Korean watersheds. Further studies will address the causes for geographic speciation of O. sinensis haplotypes.

• Natural Product Sciences
• /
• v.3 no.2
• /
• pp.106-107
• /
• 1997

Indole-3-methylethanoate was isolated for the first time form natural source i.e. from the leaves of Camellia sinensis (L.) O. Kuntz and fully characterized by physical and chemical evidence, the biological activity of the compound was studied by wheat coleoptile bioassay which showed growth promoting activity.

• Natural Product Sciences
• /
• v.3 no.1
• /
• pp.11-13
• /
• 1997

From the methanolic extract of defatted tender leaf of Camellia sinensis a new 4-hydroxy angular furocoumarin $C_{12}H_8O_5$, m.p. $212^{\circ}C$, was isolated using high-speed counter-current chromatographic technique. The structure of the compound was established as 4-hydroxy-2'-methoxy angular furocoumarin on the basis of physical methods viz. $^1H$ NMR, $^{13}C$ NMR and MS.

• Biomedical Science Letters
• /
• v.25 no.3
• /
• pp.288-292
• /
• 2019

In vitro antimicrobial activities of hot water extracts of Camellia sinensis (L.) O. Kuntze, for carbapenem-resistant Enterobacteriaceae (CRE) were compared to commonly used conventional antimicrobial agents. CRE was not only resistant to imipenem, meropenem or ertapenem, but also to various antimicrobial agents, such as amikacin (> $128{\mu}g/mL$). The hot water extracts of Camellia sinensis (L.) O. Kuntze had the lowest MIC ($0.06{\sim}0.5{\mu}L/mL$) of the carbapenem-resistant E. coli, K. pneumoniae, and Enterobacter spp. tested, and it was possible more potent than various conventional antimicrobial agents. Synergistic combinations of the extract with used commonly antimicrobial agents might even improve its antimicrobial chemotherapy property.

• Korean Journal of Ichthyology
• /
• v.25 no.1
• /
• pp.33-37
• /
• 2013

A study on the structures of the pharyngeal bones and teeth in two Korean ricefishes, Oryzias latipes and O. sinensis, was carried out to find out interspecfic differences. In the pharyngeal bones, both two species have a pair of upper pharyngeal bone (stilliform shape) and lower pharyngeal bone (rectangular shape). In the lower pharyngeal bones, in particular, the number of the row was 6 to 7 in O. latipes and 5 to 6 in O. sinensis. The pharyngeal teeth also showed different types in two species: O. latipes of a top-hooked type and O. sinensis of a conical type. Through this study, we confirmed that the two Korean ricefishes show distinctive characteristics in the structure of the pharyngeal teeth.

• Natural Product Sciences
• /
• v.6 no.2
• /
• pp.79-81
• /
• 2000

Investigation of the fruits of Chaenomeles sinensis (Rosaceae) resulted in the isolation of a minor flavonoid. The structure of flavanone glycoside was determined to be as $2-hydroxynaringenin-7-O-{\beta}-glucoside$ on the basis of FAB-MS and spectral evidence, especially by 2D-NMR $(^1H-^1H\;COSY,\;HMQC,\;HMBC\;and\;NOESY)$.

• Proceedings of the PSK Conference
• /
• 2003.10b
• /
• pp.201.3-201.3
• /
• 2003

The ethanol extract from the fruit of Terminalia chebula (Combretaceae) and the hook of Uncaria sinensis (Rubiaceae) exhibited significant inhibitory activity on oxidative stress and the age-dependent shortening of the telomeric DNA length. In the peroxidation model using t-BuOOH, human epidermal keratinocytes-neonatal foreskin (HEK-N/F) cells were treated with the T. chebula and U. sinensis extracts. The results showed a notable enhancing effect on the cell viability of 60.5 ${\pm}$ 3.8 and 65.0 ${\pm}$ 3.0%, respectively, by 50 $\mu\textrm{g}$/ml of the extracts. (omitted)

• Proceedings of the Plant Resources Society of Korea Conference
• /
• 2007.11a
• /
• pp.366.1-366.1
• /
• 2007

• Korean Journal of Ichthyology
• /
• v.18 no.3
• /
• pp.163-169
• /
• 2006

The Korean ricefish, Oryzias, consisted of 2 species, O. latipes and O. sinensis. Through investigation on their distributions, it was confirmed that O. sinensis was restricted to western areas, and O. latipes was distributed throughout Korea. Interestingly, Daecheon region near the West Sea was sympatric, existing O. latipes and O. sinensis. In addition to their distributions, O. latipes was well distinguished from O. sinensis as the following morphological characteristics: mean 31 vertebrae (vs. 30), mean 15 gill rakers (vs. 12), lots of dots in both sides of body (vs. absent), and yellowish ventral and anal fins (vs. blackish).