• Korean Journal of Environmental Biology
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• v.36 no.4
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• pp.576-583
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• 2018

Investigation of optimal temperature, irradiance and photoperiod conditions for free-living gametophytes of Saccharina sculpera for natural resources conservation and mass cultivation of endangered species in the eastern coast of Korea. Induction of regeneration and maturation of the free-living gametophytes of S. sculpera were cultured at temperatures (5, 10, 15, 20 and $25^{\circ}C$), irradiance (10, 20, 40, 60 and $80{\mu}mol\;photons\;m^{-2}\;s^{-1}$ and photoperiods (14:10, 12:12 and 10:14 h L:D). The female gametophyte were actively regenerated without reaching sexual maturity under $10^{\circ}C$, $20{\mu}mol\;photons\;m^{-2}\;s^{-1}$ and 12:12 h (L:D) conditions. In contrast, the conditions for male gametophytes were slightly different at $15^{\circ}C$, $10{\mu}mol\;photons\;m^{-2}\;s^{-1}$ and 12:12 h (L:D). The sexual maturation of female and male gametophytes took place under $15^{\circ}C$, $40{\mu}mol\;photons\;m^{-2}\;s^{-1}$, 14:10 h (L:D) and $10^{\circ}C$, $20{\mu}mol\;photons\;m^{-2}\;s^{-1}$, 10:14 h (L:D), respectively. These results provide basic information for controlling the regeneration and maturation of free-living gametophytes for conservation and utilization of S. sculpera.

• Journal of environmental and Sanitary engineering
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• v.12 no.1
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• pp.85-95
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• 1997

Behavior of Listeria monocytogenes in Skim milk during fermentation by Lactobacillus bulgaricus YI-2 and Streptococcus lactis FYI-1 were determined. Autoclaved skim milk was inoculated with ca. 10$^{3}$ L. monocytogenes (Strain LM91-1 or LM 96-2) cells/ml, and with 5.0, 1.0, 0.5 or 0.1% of a milk culture of either L. bulgaricus TI-2 or S. lactis FYI-1. Skim milk containing ca. 10$^{3}$ L. monocytogenes was incubated at 37 or 42$\circ $C for 15 h with L. bulgaricus YI-2, and at 21 or 30$\circ $C for 15 h with S. lactis FYI-1. Cultured skim milks were stored at 4$\circ $C in the refrigerater. Samples were plated on Oxford Agar with oxford antimicrobic supplement to enumerate L. monocytogenes and on either modified MRS agar to enumerate lactic acid bacteria. L. monocytogenes survived the 15-h fermentation with S. lactis FYI-1 in all combinations of level of inoculum and temperature of incubation, but inhibition of growth ranged from 94 to 100%. When incubated with over the 1.0% of L. bulgaricus, L. monocytogenes inhibited or disappeared in fermented skim milk from 9 h after incubation. Especially, incubation at 42$\circ $C with 5.0% L. bulgaricus YI-2 as inoculum appeared to be the most effective inhibitory combination for strain LM 91-1, causing 100% inhibition in growth based on maximum papulation attained. In most instances of incubated with L. bulgaricus YI-2, growth of the pathogene appeared to be completely inhibited when the pH dropped below 4.38.

• YAKHAK HOEJI
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• v.34 no.4
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• pp.262-266
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• 1990

Acetylshikonine, isolated from the root of Lithospermum erythrorhizon showed a strong cytotoxic activity ($ED_{50}=0.10\;ug/ml$) against L1210 cell and T/C = 182% in ICR mice bearing S-180 at a dose of 5 mg/kg. Administrations of 10 mg/kg and 15 mg/kg reduced the T/C values to 60 and 77% respectively. Higher doses reveal toxicity. Seven naphthazarin derivatives synthesized showed good cytotoxic activities against L1210 cell. Especially, naphthazarin and hydronaphthazarin have strong activities ($ED_{50}=0.05\;ug/ml$ for both). Naphthazarin showed a severe toxic effect on ICR mice bearing S-180; no significant toxic effect was observed at a dose of 1 mg/kg or 2 mg/kg, but a severe toxicity (T/C = 23%) by administration of 5 mg/kg. Alkylation of C-2 of naphthazarin is necessary for reducing the toxic effect on ICR mice bearing S-180.

• Fisheries and Aquatic Sciences
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• v.18 no.2
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• pp.131-135
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• 2015

Two new bitter-tasting cyclic peptides comprising six amino acids, namely gamakamide C and D, were isolated from cultured oysters Crassostrea gigas. Dimethylaminoazobenzene sulfonyl-amino acid analysis detected Val and Leu in gamakamide C and Ile and Leu in gamakamide D. The molecular formula of gamakamide C was determined as $C_{43}H_{60}N_{7}O_8S$ by high-resolution fast atom bombardment mass spectroscopy (HR FAB-MS) ($[M+H]^+m/z822.4200{\Delta}-2.4mmu$), and that of gamakamide D was determined as $C_{43}H_{62}N_7O_8S$ by HR FAB-MS ($[M+H]^+m/z836.4379{\Delta}-2.0mmu$). Comparison of amino acid analyses and fragment ions by MS/MS among gamakamide C, D, and E (known), the structures of gamakamide C and D were confirmed $as-{\small{L}}-Val-{\small{L}}-Met(SO)-{\small{L}}-NMe-Phe-{\small{L}}-Leu-{\small{D}}-Lys-{\small{L}}-Phe-$ and $-{\small{L}}-Ile-{\small{L}}-Met(SO)-{\small{L}}-NMe-Phe-{\small{L}}-Leu-{\small{D}}-Lys-{\small{L}}-Phe-$, respectively.

• Korean Journal of Environmental Biology
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• v.33 no.2
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• pp.248-255
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• 2015

Induction of regeneration and maturation of the free-living gametophytes of Saccharina japonica was studied at four temperatures (5, 10, 15 and $20^{\circ}C$), four levels of irradiance (5, 10, 20 and $40{\mu}mol\;m^{-2}\;s^{-1}$) and three photoperiods (14 : 10, 12 : 12 and 10 : 14 h L : D). Female gametophyte fragments were maintained in active regeneration without reaching sexual maturity under conditions of $15^{\circ}C$, $20{\mu}mol\;m^{-2}\;s^{-1}$, 10 : 14 h (L : D), whereas the conditions for male gametophytes were slightly different at $15^{\circ}C$, $5{\mu}mol\;m^{-2}\;s^{-1}$, 14 : 10 h (L : D). The sexual maturation of female and male gametophytes took place under $5^{\circ}C$, $20{\sim}40{\mu}mol\;m^{-2}\;s^{-1}$, 10 : 14 h (L : D) and $15^{\circ}C$, $40{\mu}mol\;m^{-2}\;s^{-1}$, 10 : 14 h (L : D), respectively. These results provide basic information for controlling the regenerationand maturation of free-living gametophytes for strain improvement and cross breeding of S. japonica.

• Journal of Aquaculture
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• v.8 no.1
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• pp.59-67
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• 1995

Growth rate, first reproductive age, life span and total offspring numbers were measured to study the effects of water temperature and salinity on the propagation of rotifer, Brachionus plicatilis. Three types of rotifer, Large (L), Small (S) and Thailand Small (TS)-types, were cultured in the $4\times4$ factorial culture conditions with four different salinities (5, 15, 25 and $35\%o$) at each of four different water temperatures (15, 20, 25 and $29^{\circ}C$). The results are as follows; Under the 4 different salinity gradients %$(5\%o,\;15\%o,\;25\%o,\;and\;35\%o)\;at\;29^{\circ}C$, the mean growth rates of L, Sand TS-type were 0.60, 0.84 and 0.96, respectively. The first reproductive age of three types rotifer appeared to be early at high water temperature. The total offspring numbers of the three types were higher at $25^{\circ}C\;and\;29^{\circ}C$, with the maximum value of 28.3 on the average at $29^{\circ}C$ for TS-type, and the minimum value at $15^{\circ}C$ for S-type. Life span decreased with high water temperature and increased with low water temperature. L-type and TS-type rotifer showed the longest life span of 13.5 days on the average at $15^{\circ}C$, and S-type showed shortest 6.2 days on the average at $29^{\circ}C$.

• Journal of Sericultural and Entomological Science
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• v.40 no.1
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• pp.78-85
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• 1998

Colorants were prepared by extraction of natural indigo which was harvested just in the blooming season(in the late of July). 100 g of fresh leaves soaking in 1 ιwater was kept at 3$0^{\circ}C$, 30 hours. A solution of 3g/l calcium hydroxide was added into it to precipitate dye substance and it was freezing-dried into powder form. The fermentation and dyeing conditions were investigated. The results obtained are summarized as follows; K/S value of dyed silk fabrics of fermentation conditions was higher at 95$^{\circ}C$ for 20 min. than at 4$0^{\circ}C$ for 20 hours. Furthermore, K/S value of dyed silk fabric was raised by the addition of 5g/l of glucose and 5g/l of NaOH. K/S value of dyed silk fabric was raised by the addition of 5g/l of glucose and 5g/l of NaOH. K/S value increased as extending of dyeing time when dyed till 2 hours at 3$0^{\circ}C$. K/S value decreased in order of 3$0^{\circ}C$, 4$0^{\circ}C$ and 5$0^{\circ}C$, at the various dyeing temperatures and dyeing concentrations, and colour fastness ranged from 4 to 5 grade in terms of washing, perspiration and light fastness.

• Korean journal of food and cookery science
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• v.13 no.5
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• pp.602-608
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• 1997

The antibacterial activity of low concentrations of clove (Eugenia caryophyllata Thumb) in culture broth against Listeria monocytogenes and Salmonella typhimurium was tested at 35, 5, and -20$^{\circ}C$. Tryptic soy broth (TSB) containing 0∼0.5% (w/v) of clove was inoculated with 10$\^$5/∼10$\^$7/ cell/ml of L. monocytogenes and S. typhimurium and incubated at each temperature. The growth of L. monocytogenes occured only after a prolonged lag period at 0.1% clove at 35$^{\circ}C$, while viabilities of the cells decreased by 1.4 and 3.3 log cycles at 0.3 and 0.5% clove, respectively. Growth of S. typhimurium occured at the presence of 0∼0.5% clove after a longer lag period with increasing concentration of clove at 35$^{\circ}C$. During refrigerated storage at 5$^{\circ}C$, the growth of L. monocytogenes occured after 6 days of lag period at 0.1% clove while viability of the cells were decreased during 24 days of storage. During frozen storage at -20$^{\circ}C$, the viability of L. monocytogenes and S. typhimurium decreased about 4 log cycles during 3 days of early period of storage at 0.1% clove. There were no major changes in the population of L. monocytogenes and S. typhimurium in TSB with different concentrations of clove during frozen storage.

• ALGAE
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• v.26 no.1
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• pp.79-86
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• 2011

Physiological studies on the hybrid by crossing between two dioecious species, Porphyra pseudolinearis and P. dentata from Korea were conducted at constant temperatures (5, 10, 15, 20, and $25^{\circ}C$), at photon flux densities (10, 20, 40, and $80\;{\mu}mol\;m^{-2}s^{-1}$) under photoperiods (14 L : 10 D and 10 L : 14 D). In the hybrid, higher growth of conchocelis was observed at 20 and $40\;{\mu}mol\;m^{-2}s^{-1}$ under 14 L : 10 D. Conchosporangial branches were produced under $10-80\;{\mu}mol\;m^{-2}s^{-1}$ at only $25^{\circ}C$, and were abundant when the conchocelis was cultured under 10 L : 14 D. Foliose thalli of the hybrid grew well at the conditions of $10-20^{\circ}C$, 10 L : 14 D and $15-20^{\circ}C$, 14 L : 10 D. The foliose thalli grew very slowly at $5^{\circ}C$ and $30^{\circ}C$, respectively. No archeospores were observed at any culture conditions. Spermatangial and zygotosporangial sori were formed at the marginal portion of mature thallus. Zygotospores from the hybrid were released at $10-2^{\circ}C$ under both photoperiods, and gave rise to form conchocelis filament. Monoecious thalli were observed at $10^{\circ}C$ under 14 L : 10 D. Neither monospores nor protothalli were produced from the conchocelis in culture.

• Korean Journal of Environmental Biology
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• v.35 no.4
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• pp.622-630
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• 2017

The induction of regeneration and the maturation of the free-living gametophytes of Undaria pinnatifida were studied at temperatures(5, 10, 15 and $20^{\circ}C$), irradiance (5, 10, 20 and $40{\mu}mol\;photons\;m^{-2}\;s^{-1}$) and photoperiods (14 : 10, 12 : 12 and 10 : 14 h L: D). Female gametophyte fragments were maintained in active regeneration without them reaching sexual maturity under conditions of $15^{\circ}C$, $20{\mu}mol\;photons\;m^{-2}\;s^{-1}$, 10 : 14 h (L : D); by contrast, the conditions for male gametophytes were slightly different at $15^{\circ}C$, $5{\mu}mol\;photons\;m^{-2}\;s^{-1}$, 14 : 10 h (L: D). The sexual maturation of female and male gametophytes took place under $5^{\circ}C$, $20-40{\mu}mol\;photons\;m^{-2}\;s^{-1}$, 10 : 14 h (L : D) and $15^{\circ}C$, $40{\mu}mol\;photons\;m^{-2}\;s^{-1}$, 10 : 14 h (L : D), respectively. These results provide basic information for controlling the regeneration and maturation of free-living gametophytes for srain improvement as well as the cross breeding of U. pinnatifida.