• Microbiology and Biotechnology Letters
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• v.26 no.3
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• pp.250-256
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• 1998

D-Tagatose production from D-galactose was investigated using 35 type strains of American Culture Type Collection (ATCC) and Korean Collection for Type Cultures (KCTC) which have potential to produce D-tagatose. Enterobacter agglomerans ATCC 27987 was selected as a D-tagatose producing strain due to its short fermentation time and high production of D-tagatose. Optimization of the culture conditions for D-tagatose production by E. agglomerans ATCC 27987 was performed. Among various carbon sources, D-galactose was the most effective carbon source for D-tagatose production. As the D-galactose concentration was increased, cell growth and D-tagatose production increased. Effect of nitrogen sources on D-tagatose production was studied. Of inorganic nitrogen sources, ammonium sulfate was effective one for D-tagatose production and yeast extract was the most suitable organic nitrogen nutrient. The concentrations of inorganic compounds such as KH$_2$PO$_4$, K$_2$HPO$_4$, and MgSO$_4$$.$7H$_2$O were also optimized for D-tagatose production. The optimal medium was determined to contain D-galactose of 20 g/l, yeast extract of 5.0 g/l, (NH$_4$)$_2$SO$_4$ of 2.0 g/l, KH$_2$PO$_4$ of 5.0 g/l, K$_2$HPO of 5.0 g/l, and MgSO$_4$$.$7H$_2$O of 5 mg/l. The optimal environmental conditions in a 250-$m\ell$ flask were found to be pH of 6.0, temperature of 30$^{\circ}C$, and agitation speed of 150 rpm. D-tagatose of 0.41 g/l could be obtained in 24 h from 20 g/l D-galactose at the optimal culture condition without induction and cell concentration.

• KSBB Journal
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• v.27 no.2
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• pp.97-102
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• 2012

In the present study, the biomass productivity of two green microalgae (Chlorella sp. and Dunaliella salina DCCBC2) were assessed in a 12 L tubular photobioreactor under optimum culture conditions. In the batch culture optimization process, the Chlorella sp. biomass was obtained as 1.2 g/L under atmospheric air as a sole $CO_2$ source and other culture conditions as follows: light intensity, temperature, pH, $NH_4Cl$ and $K_2HPO_4$ were 100 ${\mu}E/m^2/s$, $27^{\circ}C$, 7.0, 20.0 mM and 2.0 mM, respectively. On the other hand, 2.9 g/L of D. salina DCCBC2 biomass production was observed under the following conditions: light intensity, temperature, pH, $KNO_3$ and $K_2HPO_4$were 80 ${\mu}E/m^2/s$, $27^{\circ}C$, 8.0, 3.0 mM and 0.025 mM, respectively. At 1% $CO_2$ supply to the reactor, the Chlorella sp. production was reached 1.53 g/L with 25% increment under the same operating conditions. In addition, the maximum D. salina DCCBC2 biomass was observed as 3.40 g/L at 3% $CO_2$ concentration. Based on the aforementioned optimized conditions, the dilution rate and maximal biomass productivity of Chlorella sp. and D. salina DCCBC2 in the continuous cultivation were 0.4/d and 0.6 g/L/d and 0.6/d and 1.5 g/L/d, respectively.

• Korean Journal of Food Science and Technology
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• v.35 no.6
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• pp.1244-1247
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• 2003

The purpose of this study was to isolate lactic acid bacteria that produced L(+) lactic acid from infant feces. Thirteen colonies were isolated with a MRS-plate containing 0.5% $CaCO_3$ to determine their ability to produce lactic acid. Based on their lactic acid production, 10 strains of Lactobacillus were identified to assess the ratio of lactate isomer using HPLC. A strain producing L-lactic acid was identified as Lactobacillus acidophilus, using API carbohydrate fermentation patterns and physiological tests, and named KY1909. The strain exhibited good acid tolerance in an artificial gastric juice as well as high bile resistance in MRS containing 0.5% bile acids. L. acidophilus KY1909 produced D(-) and L(+) lactic acid at a ratio of 6 : 94; whereas commercial strains of Lactobacillus acidophilus produced D(-) and L(+) lactic acid at a ratio of 1 : 1. These results demonstrate the L. acidophilus KY1909 can be utilized in fermented milk products and dietary supplements as a probiotic culture.

• Journal of Life Science
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• v.8 no.4
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• pp.410-415
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• 1998

Procine pepsin hydrolysis of hexapeptide L-S-pNF-Nle-A-OMe in the presence of dipeptide L-L generates a new peak on HPLC analysis of reaction mixtures that is not seen when enzyme is incubated with either peptide alone. The peaks can be detected spectroscopically at either 214 or 254 nm, the latter consistent with a new peptide containing the p-nitro-F residue. The data suggest acyl transpeptidation between E(L-S-pNF) and L-L to form L-S-pNF-L-L. Consistent with this inference are (1) the ability of L-L-NH$_{2}$ and inability of Boc-L-L to undergo a similar transpeptidation reaction, and (2) the data from electrospray mass spectrum. This synthesis requires that Nle-A-L-OMe be released before L-S-pNF, an order opposite to that proposed on the basis of product inhibition kinetics. Consistent with this inference are reciprocal solvent isotope effects ; normal isotope effects of 1.736$\pm$0.121 on the formation of Nle-A-L-OMe and 2.281$\pm$0.184 in the formation of L-S-pNF, coupled to an inverse isotope effects of 0.576$\pm$0.045 on the formation of L-S-pNF-L-L. Because transpeptidation precedes faster in D$_{2}$O, the isotopically-sensitive step must occur after release of Nle-A-L-OMe. Isotopically-enhanced transpeptidation is consistent with the Uni-Bi iso memchanism postulated on the basis of an isotope effects on Vmax but not on Vmax/Km$^{1)}$ and confirmed by isotope effects on the onset of inhibition by pepstatin$^{2)}$.

• Journal of the Korean association of regional geographers
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• v.22 no.1
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• pp.86-101
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• 2016

La situation de la $r{\acute{e}}gion$ rurale et maritime de la province de Jeollanam-do en $Cor{\acute{e}}e$ du sud se $caract{\acute{e}}rise$ par une relative $p{\acute{e}}nurie$ de population. Le projet 'Ces ${\hat{I}}les$ que l'on aime visiter', $g{\acute{e}}r{\acute{e}}$ par la province de Jeollanam-do, s'articule autour de villages insulaires lieux de bien- ${\hat{e}}tre$ pour viser une augmentation de la population. Il s'agit de $d{\acute{e}}velopper$ le tourisme durable en s'appuyant sur la $beaut{\acute{e}}$ des paysages naturels, l'histoire, la culture et les traditions de cette $r{\acute{e}}gion$ insulaire. Pour cela, la participation active des habitants est essentielle. Cette ${\acute{e}}tude$ a pour but de $r{\acute{e}}fl{\acute{e}}chir$ aux moyens de $d{\acute{e}}velopper$ la participation des habitants en se fondant sur une $enqu{\hat{e}}te$ $men{\acute{e}}e$ dans la campagne. Nous avons mutuellement $analys{\acute{e}}$ entre les moyens de la participation des habitants et l'apanage $d{\acute{e}}mographique$ ${\grave{a}}$ cause de leurs $r{\acute{e}}sultats$ $diff{\acute{e}}rentes$. Voici les moyens de la participation des habitants $fond{\acute{e}}s$ sur la $caract{\acute{e}}ristique$ communautaire: $l^{\prime}activit{\acute{e}}$ $r{\acute{e}}mun{\acute{e}}ratrice$ communautaire; $l^{\prime}am{\acute{e}}lioration$ de l'habitat; les loisirs dans la $r{\acute{e}}gion$. Nous proposons plusieurs exemples pour $d{\acute{e}}velopper$ des programmes $fond{\acute{e}}s$ sur la participation des habitants de $l^{\prime}{\hat{i}}le$ de Nangdo, d'un rite communautaire maritime et des programmes ${\acute{e}}ducationnels$ d'explication touristique.

• Journal of Environmental Science International
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• v.6 no.1
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• pp.9-16
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• 1997

We investigated and analysed the actual conditions and characteristics of railroad noise levels for 17 sites in the vicinity of the Seoul-Pusan Line. The results i,we summarized as follows : 11 Railroad noise level ranged to 64 ~ 74 $L_{eq}$ dB(A) at day time and ranged to 60 ~ 72 $L_{eq}$ dB(A) at night time. 21 Increased night noise level depend on the increase of trains passing at night time. 31 The major factor of Increased noise level in the vicinity of stations are using loudspeakers and stream whistle on trains. 4) Decreased effect of noise according to distance is able to be described quantitatively using regression equations of multiplicative model. $L_{eq}$=$78.59^{X-0.056}$, n =25, r=-0.994, s.e. =1.007 $P_{av}$ = $105.68X^{-0.073}$, n =25, r =-0.997, s.e. = 1.007 Also increased and decreased effect of noise according to floor in apartment Is able to be described quantitatively using regression equations of multiplicative model. $L_{eq}$ = $64.238X^{0.0567}$, n = 39, r = 0.787, s.e. = 1.004 $P_{av}$ =79.963X0.0524, n =39, r =0.689, s.e. = 1.056 5) Average noise level in high floor is over 70 $L_{eq}$ dB(A) at day and night time. so more detailed soundproofing countermeasured in high floors apartment is required.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.41 no.5
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• pp.381-388
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• 2008

Induction of regeneration and maturation for the free-living gametophytes of Ecklonia cava Kjellman was conducted under various temperature, irradiance and photoperiod conditions. Culture conditions for female or male gametophyte fragments were 4 temperature (5, 10, 15 and $20^{\circ}C$), 4 irradiance (5, 10, 20 and $40{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$) and 3 photoperiod (14:10, 12:12 and 10:14 h L:D). Female and male gametophyte fragments were maintained in active regeneration without reaching sexual maturity under $5{\sim}10^{\circ}C$, $5{\sim}10{\mu}mol{\cdot}m-2{\cdot}s-1$, 12:12h or 10:14h (L:D) and $15-20^{\circ}C$, $20-40{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$, 14:10h (L:D), respectively. Sexual maturation of female and male gametophytes facilitated under $15^{\circ}C$, $20-40{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$, 14:10h (L:D) and $5-10^{\circ}C$, $5-10{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$, 10:14h (L:D), respectively. These results provide basic informations to control the regeneration or maturation of the free-living gametophytes for artificial seed production of E. cava.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.2
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• pp.155-161
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• 2011

Induction of regeneration and maturation of the free-living gametophytes of Undariopsis peterseniana (Kjellman) Miyabe et Okamura 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 $15^{\circ}C$, 20 ${\mu}mol\;m^{-2}\;s^{-1}$, 14:10 h (L:D). The sexual maturation of female and male gametophytes took place under $15^{\circ}C$, 20 ${\mu}mol\;m^{-2}\;s^{-1}$, 14:10 h (L:D) and $10^{\circ}C$, 10 ${\mu}mol\;m^{-2}\;s^{-1}$, 10:14 h (L:D), respectively. These results provide basic information for controlling the regeneration and maturation of free-living gametophytes for artificial seed production of U. peterseniana.

• Kyungpook Mathematical Journal
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• v.63 no.3
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• pp.425-435
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• 2023

The classical Hardy Theorem on R states that a function f and its Fourier transform cannot be simultaneously very small; this fact was generalized by Miyachi in terms of L¹ + L^∞ and log⁺-functions. In this paper, we consider the k-Hankel transform, which is a deformation of the Hankel transform by a parameter k > 0 arising from Dunkl's theory. We study Miyachi's theorem for the k-Hankel transform on ℝ^d.

• Proceedings of the Korean Magnestics Society Conference
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• 2007.05a
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• pp.194.1-194.1
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• 2007