• Korean Journal of Microbiology
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• v.25 no.4
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• pp.309-317
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• 1987

It was known that normal-haemolymph from the 3rd instar larvae of Lucillia illustris contain a lysozyme (or lysozyme-like substance) with bactericidal activity to fram positive bacteria, and the bactericidal activity of injured-haemolymph was increased significantly after injuring the body wall. To elucidate the defence mechanism of insect against the nonpathogenic bacteria, the immune-haemolymph against Escherichia coli K-12 was prepared after immunization. The bactericidal activity between injured and immune-haemolymph was compared, and it was revealed that the immune-haemolymph showed higher titer of bactericidal activity to fram positive bacteria as well as to Escherichia coli. The bactericidal substance from the immune-haemolymph was purified through a successive chromatographies on Sephacryl S-300 and CM-Sepharose CL-6B, and it was characterized as a basic protein in nature with heat stable property at acidic conditions.

• Food Science of Animal Resources
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• v.29 no.3
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• pp.302-309
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• 2009

This study investigated the effects of infrared (IR) radiation combined with air blast thawing on the physical properties of pork. Regardless of air velocity, increasing IR dosage produced an exponential increase in the thawing rate of pork. This rate increased further when air blast velocity was increased. IR treatments showed significantly lower thawing loss than that of 0 Watt treatment, while increasing air velocity significantly increased thawing loss of pork (p<0.05). Increasing both IR power and air velocity tended to decrease the cooking loss of pork. Moreover, increased IR power tended to decrease the water holding capacity and shear force of pork. The shear force changes were not significant (p>0.05). Shear force also increased with increasing air velocity. In addition, the higher the air velocity the higher the shear force of pork. In Commission Internationale de l'Eclairage (CIE) colour determination, control of temperature prevented discolouration from overheating of sample surface. The results suggest that IR dosage combined with air blast has potential in thawed meat quality aspects, and that humidity control could prevent surface drying.

• Journal of Plant Biology
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• v.39 no.4
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• pp.309-314
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• 1996

Developmental of photosynthetic pigments and changes in chlorophyll fluorescence of dark-grown rice seedlings were studied during greening. Light-illumination stimulated accumulations of total chlorophylls and carotenoids in leaves of etiolated seedlings, accompanied by a decrease in the ratio of chlorophyll a to chlorophyll b. When the composition of carotenoids was analyzed, violaxanthin level was shown to increase up to 24 h after the beginning of light illumination, followed by a subsequent decline. In contrast to this, zeaxanthin level increased consistently with progress of deetiolatin. The role of zeaxanthin is discussed in relation to chlorophyll fluorescence quenching. A study on chlorophyll fluorescence kinetics of the rice seedlings being deetiolated showed a time-dependent increase in Fv/Fm (yield of variable fluorescence/maximum yield of fluoresecnece) ratios, indicating that greening is responsible for the activation of photochemical reaction centers of the photosystem. When chlorophyll fluorescence quenching was examined, qNP (nonphotochemical quenching) and qE (energy-dependent quenching) exhibited a time-dependent decline with progress of greening. The presented results indicate that greening-induced development of the photosynthetic machinery is associated the conversion of the carotenoid violaxanthin to zeaxanthin, suggesting that zeaxanthin synthesized in the illuminated leaves may provide the protection from the damage when etiolated plants are exposed to light.

• Bulletin of the Korean Chemical Society
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• v.21 no.3
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• pp.305-309
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• 2000

The cerium ion intercalated aluminosilicate was prepared by ion exchange reaction between $Na^+$ in montmorillonite and $Ce^{+4}$ in aqueous solution. The X-ray absorption near edge structrure(XANES) analyses indicate that the $Ce^{+4}$ ions are partially reduced to the $Ce^{+3}$ ones during the intercalation into layered aluminosilicate due to a charge transfer between host and intercalant. From the EXAFS analysis, two different (Ce-O) bonding pairs could be characterized with the distances and coordination numbers of 2.31 $({\pm}0.02){\AA}$ ${\times}$ 8.2 $({\pm}1.5)$ and 2.66 $({\pm}0.02){\AA}$ ${\times}$ 2.7 $({\pm}1.0)$, respectively, with the oxygen atoms as the first nearest neighbor, and two (Ce-Ce) pairs at 3.78 ${\AA}$ as the second neighbor. It is therefore concluded that the most probable Ce-species stabilized in the interlayer space of aluminosilicate after the intercalation is the tetrameric Ce-polyoxy/hydorxy cations with the mixed valent state of 0.75 $Ce^{+4}$.0.25 $Ce^{+3}$.

• Journal of the Korean Society of Food Culture
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• v.36 no.2
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• pp.210-217
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• 2021

This study evaluated the biological activity and cytoprotective effect of guava (Psidium guajava L.) branch against oxidative stress. The contents of vitamin C, beta-carotene, total carotenoids, quercetin and catechin determined were 26.783, 43.676, 65.083, 58.245, and 8.309 mg/100 g, respectively. To measure antioxidant activity, the guava branch was extracted using various concentrations of ethanol (60, 80, or 100%) and water. The highest content of polyphenols (0.245 mg gallic acid equivalent/mg residue) and flavonoids (0.128 mg cathechin equivalent/mg residue) was found in the 100% ethanol extract of the branch (E100). Moreover, E100 also possessed the highest radical scavenging activities and showed the highest inhibition rate of α-glucosidase (77.692%). E100 was the most effective extract to impart cytoprotectant activity against oxidative stress in HepG2 cells. Taken together, our results determine the promising antioxidant activity of guava branch, and indicate the potential to be applied as a natural antioxidant.

• Journal of Powder Materials
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• v.30 no.4
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• pp.305-309
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• 2023

This study aims to prepare a colloidal silica-containing powder to enhance the solubility and dissolution rate of rivaroxaban using a self-nanoemulsifying drug delivery system (SNEDDS). We investigate the impact of colloidal silica on a nanoemulsion system for preparing powdered SNEDDS. The liquid SNEDDS comprises 30/20/50 (w/w/w) Peceol/Cremophor RH40/Tween 80, which results in the formation of the smallest droplets. Three powdered SNEDDS formulations are prepared by suspending the liquid SNEDDS formulation using colloidal silica and spray drying. The powdered SNEDDS prepared with liquid SNEDDS and colloidal silica at a ratio of 1/0.5 (w/w) exhibits the highest water solubility (0.94 ± 0.62 vs. 26.70 ± 1.81 ㎍/mL) and dissolution rate (38.4 ± 3.6 vs. 85.5 ± 3.4%, 45 min) when compared to the drug alone. Morphologically, the liquid SNEDDS is adsorbed onto colloidal silica and forms smaller particles. In conclusion, an SNEDDS containing rivaroxaban, prepared using colloidal silica, facilitates the creation of a nanoemulsion and enhances the water solubility of rivaroxaban. Accordingly, this technology holds significant potential for commercialization.

• Analytical Science and Technology
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• v.13 no.3
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• pp.309-314
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• 2000

The quantitative analysis of various trace metals including fission products in lithium molten salts has been performed using a inductively coupled plasma atomic emission spectrometer (ICP-AES). The spectral interferences of lithium content, 500, 1,000 and 2,000 mg/L, in the sample solution were investigated using an optimum wavelength for the respective metal species. As a result, the line intensities for Y, Nd, Sr, and La had no influences from the lithium content up to 2,000 mg/L, while Mo, Ba, Ru, Pd, Rh, Zr and Ce showed spectral interferences of 10% to 50%. The group separation of metals from lithium in the molten salts solution was carried out by adding ammonia water into the solution. The recovery of Ru, Y, Rh, Zr, Nd, Ce, La and Eu was found to be over 90%, while Mo, Ba, Pd, and Sr provided low recovery percentages.

• Journal of Bio-Environment Control
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• v.6 no.4
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• pp.299-309
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• 1997

This experiment was conducted to determine the mineral absorption character and develop the optimum composition of nutrient solution for dill(Anethum graveolens L.) in hydroponics. Dill(Anethum graveolens L.) plants were grown in nutrient film technique(NFT) supplied with 1/4, 1/2, and 1 strength of the nutrient solution developed by National Research Station in Japan(HRS). Plants grown in 1/2 strength showed the best growth in plant height, fresh weight, and dry weight compared with those grown in 1/4 or 1 strength. In 1/2 strength solution, pH and EC changed little and proper nutrient contents were observed in the leaves as compared to plant nutrient diagnosis standard. Based on these results, optimum macronutrients were composed by nutrient- water absorption rate(n/w) with 1/2 strength: NO$_2$―N 8.85, NH$_4$―N 0.55, P 2.1, K 6.2, Ca 2.8, and Mg 1.7 me L$^{-1}$ To examine the suitability of the nutrient solution developed(SCU) , dill plants were grown in NFT supplied with two different kinds of solution and concentration. 1/2, 1, 3/2 and 25 of SCU and 1/2S of HRS. Changes of pH and EC were not distinct in 1S, but a significant change of pH was shown in low concentrations-HRS 1/2S and SCU 1/2S. Shoot fresh and dry weight were much higher in the plants grown in SCU IS as compared with HRS 1/2S. There were no significant differences in growth of plants grown in SCU IS, 3/2S, and 25. In addition, nutrient contents in the leaves grown by SCU 1S were in proper levels as compared with plant nutrient diagnosis standard. SCU 1S developed in this experiment was found to be optimum for dill in hydroponics.

• Food Science of Animal Resources
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• v.23 no.4
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• pp.309-314
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• 2003

Color and its stability in venison, longissumus dorsi (LD) and quadriceps femoris (QF) muscles, from 8 wild Cervus nippon yesoensis (Japanese Yeso Deer) were investigated by means of the CIE L$^{*}a{*}b{*}$ measurement and autoxidation rate recorded using partially purified myoglobin. It was observed a common feature of the change of three mean values($L^{*}$, $a^{*}$ and $b^{*}$) in both LD and QF that mean value increased at 1 or 2 day post-mortem and then decreased during storage. The differences between 1 and 7 days was the largest in $a^{*}$ value than those in $L^{*}$ and $b^{*}$ values. The mean differences among storage days were only significant in $a^{*}$ except for $b^{*}$ of LD. It was same tendency that the mean difference of CIE $L^{*}$, $a^{*}$ and $b^{*}$ values during refrigerator storage was larger in $a^{*}$ than both in $L^{*}$ and $b^{*}$ reported in beef(Sekikawa et al., 1995) and venison(Stevenson et al., 1989) during storage. The smaller $a^{*}$ value was indicated that bright red of meat changed to dull red, brown red causing met-Mb formation. To compare of color stability with respects to the Mb autoxidation rate, we measured this rate of deer and horse muscles, because horse Mb was considered to have the fastest autoxidation rate among domestic animals, and we used crude Mb and pH 6.0, which might be reflected to the intact meat. Mean value of the autoxidation rate measured in this study in deer was 0.037 and that was 0.026 in horse(sigma). Although there was no significant mean difference and were different Mb purity between deer(A409/A 280 nm = 4.0) and horse(5.6), in generally Mb purity was the higher and the faster autoxidation rate, but this rate in deer was faster than in horse. These results might indicate that venison meat discolors at faster rate compared with beef.

• Korean Journal of Plant Tissue Culture
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• v.21 no.5
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• pp.309-314
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• 1994

To develop simple and efficient transformation methods of monocotyledonous plane, electroporation-mediated delivery of DNA into intact embryogenic cell clumps was investigated in zoysiagrass and rice. Calli of zoysiagrass, induced from 3-week-old immature embryos, were suspension-cultured in MS basic medium supplemented with 1.0 mg/t 2.4-D and used for elechuporation. Calli, derived from immature inflorescences of 20 mm lenth of rice, were also suspension-cultured on N6 basic medium supplemented with 1.0 mg/L 2.4-D. Suspension-cultured embryogenic cell clumps were electroporated in liqid MS medium added with a Plasmid DNA (30 $\mu\textrm{m}$/ml), pGA1074, encoding ${\beta}$-glucuronidiase (GUS). DNA delivery into the cells through cell walls and cell membrane was confirmed by the transient expression of the GUS gene. Cell clumps of zoysiagrass and rice, electroporated with 400 volt at 800 pF capacitance, expressed GUS gene activity at a mean frequency of 25 units (one unit = one clony of blue cells) per 200 ${\mu}\ell$ of packed cell volume. Untreated cells and healed non-embryogenic cells did not exhibit GUS activity These results indicate that electroporation-mediated transformation can use intact embryogenic cells (thus avoiding the use protoplasts) in zoysiagrass and rice.