• Korean Journal of Environmental Biology
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• v.26 no.1
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• pp.15-21
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• 2008

Ionizing radiation causes many alterations in photosynthetic machineries. However, there is no information about effects of ionizing radiation on the development of photosynthetic machineries in plants. We investigated the greening of etiolated mung bean seedlings after gamma-irradiation of 50 to 300 Gy. The irradiation inhibited seedling growth with great dependence on the radiation dose. In particular, growth of stems was more affected than that of hypocotyls. Irradiated leaves showed inhibition in growth, aberration in morphology, and yellowing in color depending on the radiation dose. Contents of photosynthetic pigments such as chlorophylls and carotenoids were significantly decreased in the irradiated leaves. The apparent electron transport rate for photosynthesis, ETR, was similarly changed depending on the radiation dose. However, the maximal photochemical efficiency of Photosystem II (PSII), Fv/Fm, was little affected by the irradiation. Moreover, the 50-Gy seedlings maintained the control level of light saturating for photosynthesis and showed slightly higher Fv/Fm values in spite of significant decreases in the photosynthetic pigment content and ETR. These results suggest that the inhibition of the overall photosynthetic capacity couldn’t be causally relatqaed with the repression in the initial development of irradiated seedlings and that the overall photosynthetic machineries can develop and work to some extent as a concerted system for photosynthesis even after exposure to acute doses of ionizing radiation.

• Food Science of Animal Resources
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• v.35 no.2
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• pp.156-163
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• 2015

The effects of low molecular-weight collagen peptides derived from porcine skin were investigated on the physicochemical and sensorial properties of chocolate ice cream. Collagen peptides less than 1 kDa in weight were obtained by sub-critical water hydrolysis at a temperature of $300^{\circ}C$ and a pressure of 80 bar. Ice cream was then prepared with gelatin powder and porcine skin hydrolysate (PSH) stabilizers mixed at seven different ratios (for a total of 0.5 wt%). There was no significant difference in color between the resulting ice cream mixtures. The increase in apparent viscosity and shear thinning of the ice cream was more moderate with PSH added than with gelatin. Moreover, the samples containing more than 0.2 wt% PSH had enhanced melting resistance, while the mixture with 0.2 wt% PSH had the lowest storage modulus at $-20^{\circ}C$ and the second highest loss modulus at 10℃, indicating that this combination of hydrocolloids leads to relatively softer and creamier chocolate ice cream. Among the seven types of ice creams tested, the mixture with 0.2 wt% PSH and 0.3 wt% gelatin had the best physicochemical properties. However, in sensory evaluations, the samples containing PSH had lower chocolate flavor scores and higher off-flavor scores than the sample prepared with just 0.5 wt% gelatin due to the strong off-flavor of PSH.

• Food Science of Animal Resources
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• v.38 no.5
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• pp.995-1007
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• 2018

Changes in the physicochemical properties of ready-to-feed liquid infant formula (LIF) stored at different temperatures (10, 20, 30, and $40^{\circ}C$) for 6 mon, focusing on 5-hydroxymethylfurfural (HMF) content, color, pH, fat globule size distribution, and rheological properties were determined. The HMF content increased with storage time, and LIF stored at $40^{\circ}C$ had a higher HMF content than that of LIF stored at $10^{\circ}C$. The lightness ($L^*$) decreased while redness ($a^*$) and yellowness ($b^*$) increased with increasing HMF content. The fat globule size and pH of LIF stored at $10^{\circ}C$ did not change. However, in the case of LIF stored at $30^{\circ}C$ and $40^{\circ}C$, the fat globule size increased and the pH decreased during storage for 6 mon. LIF stored at $40^{\circ}C$ had a higher apparent viscosity (${\eta}_{a,10}$) than that of LIF stored at $10^{\circ}C$, and the shear-thinning behavior of LIF stored at higher temperature was stronger than that of LIF stored at low temperature. The physicochemical changes of LIF during storage were accelerated by Maillard reaction (MR) at higher storage temperatures. Therefore, even if LIF is aseptically manufactured, we recommend that sterilized LIF should be stored at low temperature in order to minimize quality changes during storage.

• Korean Journal of Food Science and Technology
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• v.5 no.2
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• pp.95-100
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• 1973

In order to study the effect of gamma-ray on the storage stability and quality of polished wheat, the grain was irradiated at $50{\sim}1000$ krad levels and quality assessment was made for three-month storage period. The results are summarized as follows: 1) Growth of molds was apparent at equilibrium moisture content above 14.8% of the grain, but their growth was retarded at 250 krad level. 2) Irradiation at 250 krad level had no adverse effect on fat acidity, reducing sugar content and color of the grain. 3) Irradiation of the grain caused the increase of degree of gelatinization and the decrease of viscosity. 4) Irradiation at 250 krad level brought about higher digestibility of the grain but had no effect on the rate of retrogradation.

• Biomedical Science Letters
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• v.16 no.3
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• pp.201-206
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• 2010

In order to develop procedures for the rapid isolation of recombinant sugar transporter in functional form from away from the endogenous insect cell transporter, gene fusion techniques were exploited. Briefly, BamH1-digested human HepG2 type glucose transport protein cDNA was first cloned into a transfer vector pBlueBacHis, containing a tract of six histidine residues. Recombinant baculoviruses including the human cDNA were then generated by allelic exchange following transfection of insect cells with wild-type BaculoGold virus DNA and the recombinant transfer vector. Plaque assay was then performed to obtain and purify recombinant viruses expressing the human transport protein. All the cell samples that had been infected with viruses from the several blue plaques exhibited a positive reaction in the immnuassay, demonstrating expression of the glucose transport protein. In contrast, no color development in the immunoassay was observed for cells infected with the wild-type virus or no virus. Immunoblot analysis showed that a major immunoreactive band of apparent Mr 43,000~44,000 was evident in the lysate from cells infected with the recombinant baculovirus. Following expression of the recombinant fusion protein with the metal-binding domain and enterokinase cleavage site, the fusion protein was recovered by competition with imidizole using immobilized metal charged resin. The leader peptide was then removed from the fusion protein by cleavage with porcine enterokinase. Final separation of the recombinant protein of the interest was achieved by passage over $Ni^{2+}$-charged resin under binding conditions. The expressed transport protein bound cytochalasin B and demonstrated a functional similarity to its human counterpart.

• Korean Institute of Interior Design Journal
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• v.14 no.2 s.49
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• pp.178-187
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• 2005

The Danish furniture designer, Verner Panton's work is comprised of the appreciation and application of the traditional for the application of a wide range of high-tech material accompanied by the bold and primary color used his work, the purpose of this study is to draw the expressive characteristics apparent in his work by analyzing the origin, background and case study of his design. The origin including the background of Verner Panton's design is based on the identity of the Danish Modernism and International design trend, which is revolved around the pop culture and is under the direct influence of Martin Johansen and Poul Henningsen. In order to understand the expressive characteristics found in the Verner Panton's chair design, a case study was conducted from 1955 where his debut piece of work, Cone chair was premiered at the Fredericia furniture Fair up through 1970 where Visiona 2 project was presented at the Koln International furniture fair. As a result, the total of 41 chair designs was analyzed by the following four criteria: form, finishing, functionality, and structure. According to the result of the analysis, the design by Verner Panton was based on the experiment of the organic form, his tendency to the pop culture, the concept of space, mobility, simplicity, and sensible creativity of space. Once criticized for being extemporary and consumptive, nevertheless, the outcome of Verner Panton's chairs not only introduced the fresh new and positive ideas that have been mass-producing for over 40 yews but also they keep on getting upgraded in accordance with the development of material.

• Journal of Pharmaceutical Investigation
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• v.28 no.3
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• pp.177-183
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• 1998

Low toxicity, reverse thermal gelation and high drug loading capabilities suggest that poloxamer 407 gels have great potential as a topical drug delivery system. Kojic acid (KA) is an antimelanogenic agent which has been widely used in cosmetics to whiten the skin color. However, it has the drawbacks of skin irritancy due to its acidic pH. Poloxamer gels of different polymer contents were formulated to overcome the problem and compared to the cream type formulations of either w/o/w multiple emulsion cream or o/w type emulsion cream. Using Franz diffusion cells mounted with a synthetic cellulose membrane (MWCO 12,000), drug release characteristics of the formulations were evaluated by the HPLC assay of KA concentration in the receptor compartment of pH 7.4 phosphate buffered saline solutions. Drug release from w/o/w multiple emulsion cream was controlled by oil membrane, showing the apparent zero order release kinetics. The KA release from the poloxamer gels was also controlled by the gel matrix, showing that drug release increased linearly as KA contents increase, but decreased exponentially as the polymer contents increase. In the skin irritancy test, the primary irritancy index(PII) of poloxamer gel base was lower than those of multiple emulsion cream base and o/w cream. Depending on KA contents or polymer contents in the gel. PH values in poloxamer gels were ranged from 1.3 to 2.0, which are interpreted as low or negligible irritation on skin. There was a good correlation between the log value of flux in drug release and PII value in skin irritation. It was possible to conclude that the poloxamer gels containing KA might be a good candidate for an antimelanogenic topical delivery system by virtue of the controlled release of the drug and the reduced skin irritancy.

• Macromolecular Research
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• v.9 no.2
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• pp.116-121
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• 2001

A series of poly(1,4-phenylenevinylene-alt-3-alkyl-2,5-thienylenevinylene)s (alkyl = hexyl [PPV-alt-6-TV] and octyl (PPV-alt-8-TV] group) have been synthesized by the Heck coupling reaction. These polymers were characterized using $^1$H-NMR, FT-IR spectroscopy, and thermogravimetric analysis (TCA). They are solvent processible and have obviously copolymeric structure. The photophysical properties of the polymers were investigated using UV-visible and steady-state photoluminescence(PL) spectroscopy. We studied the change of light-emitting properties by incorporating the thiophene group into the PPV polymer backbone using alternating copolymer system. The properties of two synthesized polymers are very similar, but they exhibited apparent changes of light-emitting properties compared with other PPV backbone based polymers. The broad absorption bands from 350 to 570 nm are due to $\pi$-$\pi$* transitions of the polyconjugated systems. The absorption maxima of the two polymers were found at about 452 and 448 nm for PPV-alt-6-TV and PPV-alt-8-TV, respectively. The copolymers showed broad PL spectra between 550 and 700 nm without vibronic bands and PL emission maxima of PPV-alt-6-TV and PPV-alt-8-TV are about 620 and 605 nm, respectively. The copolymers exhibited the red emission (PPValt-6-TV), but more red shifted emissions are needed to obtain real red color.

• Preventive Nutrition and Food Science
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• v.18 no.1
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• pp.45-49
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• 2013

This study was carried out to determine a possibility of adding Corni fructus extract (CFE) into yogurt for improving the neutraceutical properties of yogurt and the effects of adding CFE (2~6%, v/v) on the physicochemical and sensory properties of the products during a 15-day storage period at $4^{\circ}C$. Incorporation of CFE into the yogurt samples resulted in a significant pH reduction and a significant increase in titratable acidity. When evaluating the color of the yogurt, the $L^*$-values were not significantly influenced by CFE supplementation; however, the $a^*$- and $b^*$-values significantly increased with the addition of CFE during storage. The power law and Casson models were applied to assess the flow behavior of CFE-added yogurt samples. The magnitudes of apparent viscosity (${\eta}_{a,100}$), consistency index (K), and yield stress (${\sigma}_{oc}$) for 4~6% CFE yogurt samples were significantly greater than those for the control, indicating that CFE can be used as a thickening agent for yogurt. The sensory test revealed that addition of CFE (2~4%) to yogurt did not significantly affect the overall scores, but the overall preference score for 6% CFE yogurt was significantly decreased. Based on the data obtained from the present study, we concluded that the concentrations (2~4%) of CFE could be used to produce a CFE-added yogurt without the significantly adverse effects on the physicochemical and sensory properties.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.5
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• pp.575-581
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• 2013

We examined the effect of starvation on the occurrence of tunic softness to determine the cause of mass mortality of cultured Halocynthia roretzi (Drasche) in the Tongyeong region, Korea. In terms of the survival rate of H. roretzi and the occurrence rate of tunic softness, H. roretzi starved for 35 days at water temperatures of 8, 12, and $15^{\circ}C{\pm}0.5^{\circ}C$ (room temperature of $15^{\circ}C{\pm}1^{\circ}C$) did not exhibit tunic softness at water temperatures of either $8^{\circ}C$ or $12^{\circ}C$. for morphological changes, although the tunic of H. roretzi was shrunken and became visibly smaller with a darkening color in all experimental groups, as compared to the state prior to starvation, its tunics bulbs continuously. The ratio of RNA/DNA concentrations and protein contents for each of the tunic sections were lower in the starved group. Our results indicate that tunic softness is not related to feeding deficiency, as no histopathological symptoms were apparent in the digestive gland or tunic of H. roretzi due to starvation.