• Microbiology and Biotechnology Letters
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• v.26 no.5
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• pp.456-464
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• 1998

For the standardization and quality improvement of traditional Korean Nuruk, 10 strains of fungi, which were isolated from Nuruks and showed good productivity of the saccharogenic and dextrinogenic enzymes, acid and flavor, were selected and their enzymological characteristics and identification were carried out. Aspergillus spp. and Rhizopus sp. showed a high liquefying activity without regard to cultivation time, whereas the majority of strains except for Rhizopus sp. had decreasing saccharifying activity in proportion to the increase in cultivation time. Aspergillus spp. No.17-2, No.17-6 and Rhizopus sp. No.18-1 showed high liquefying and saccharifying activity after 15 and 30 day cultivation. The optimum temperature of most of these saccharogenic and dextrinogenic enzymes was from 40$^{\circ}C$ to 60$^{\circ}C$, and their optimum pH was extensive between pH 3 and pH 11. But Penicillium spp.(2 strains) and Rhizopus sp. showed low activity under the alkalic and acidic conditions. Among these isolated strains, 5 strains which had shown the high productivity of materials were identified as Aspergillus oryzae NR3-6 and Aspergillus oryzae NR17-6, Aspergillus penicilloides NR12-1, Penicillium expansum NR7-7 and Rhizopus oryzee NRl8-1, respectively. Five kinds of mixed culture were carried out and all of them showed a better productivity of saccharogenic and dextrinogenic enzymes than single culture. These results indicate that it is possible to make traditional Korean liquors of good quality by using these fungi.

• Food Science and Preservation
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• v.20 no.3
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• pp.386-393
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• 2013

This study was conducted to investigate the change in quality attributes of fresh-cut potatoes with heat and browning inhibitor treatment (CW: dip in the cold water for 30 sec at $4^{\circ}C$, HW: dip in the water for 60 sec at $55^{\circ}C$, AA: dip in the 0.1% solution of ascorbic acid for 60 sec at $4^{\circ}C$, HA: dip in the 0.1% solution of ascorbic acid for 60 sec at $55^{\circ}C$) during storage at $5^{\circ}C$. During storage, fresh-cut potatoes treated with HA showed the lowest value in surface color. PPO and PAL activities of fresh-cut potatoes treated with HA were gradually increased during storage. Hardness, weight loss, soluble solids content and moisture content had no significant difference between the treatments. In sensory acceptance, fresh-cut potatoes treated for HA marked the best quality. Conclusively, heat and browning inhibitor treatment showed the positive effect on browning inhibition while maintaining the quality of fresh-cut potatoes.

• Applied Microscopy
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• v.29 no.2
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• pp.241-253
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• 1999

Fertilization pattern of north temperate bats is known to be unique for their sperm storage in the female reproductive tract during hibernation (e.g. Korean greater horseshoe bats). They copulate in fall but their ejaculated spermatozoa survive until the next spring. In another words they can persist to survive during long hibernation under the cold condition $(8\sim13^{\circ}C)$ and are to be fertilized with the ovum ovulated in the next spring, so called delayed fertilization. The present study was designed to observe morphological and functional changes of spermatozoa plasma membrane of the bats, hamsters which are hibernators, and mice which are non-hibernators in the room and the cold (bat-hibernation) temperatures and to confirm influence of the temperature on spermatozoa; survival rate, acrosome reaction rate, protein distribution, $Na^+-K^+-ATPase$ activities and scanning electron microscopic histochemistry. Based on the experimental results obtained in the present study, there were no significant morphological and functional differences in the spermatozoa plasma membrane in both the room and cold (bat-hibernation) temperatures and such an absence of difference suggests that the spermatozoa plasma membrane might play a pertinent role as a protector for consistent fertilization during and after hibernation.

• The Korean Journal of Physiology
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• v.7 no.1
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• pp.1-11
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• 1973

To study the effects of Korean ginseng on mice visceral alkaline phosphatase activity and inorganic phosphate phosphorus level in the blood, the experimental groups of male and female mice were injected subcutaneously with 0.01 ml or 0.02 ml of Tyrode solution per 10 g of body weight daily, and 0. 1 mg or 0.2 mg of alcohol extract of ginseng which was diluted with Tyrode solution. After groups of mice were treated for 7 days or 14 days, the alkaline phosphatase activity in the jejunum, kidney and liver homogenate and serum were determined with sodium ${\beta}-glycerophophosphate$ as substrate, and quantified the content of inorganic phosphate phosphorus in the blood of above mice. 1. Alkaline phosphatase activity in the jejunum, kidney, liver and serum of male mice for the 7 day treatment with ginseng extract (0.1 mg/10 g) was increased by 15.28%, 12.86%, lg.05% and 11.70% respectively, compared with Tyrode solution group. 2. Alkaline phosphatase activity in the jejunum, kidney, liver and serum of female mice for the 7 day treatment with ginseng extract (0.2 mg/10 g) was increased 3.46%, 6.94%, 20.37% and 4.05 % respectively. 3. Alkaline phosphatase activity in the jejunum, kidney, liver and serum of male mice for the 14 day treatment with ginseng extract(0.1 mg/10 g) was increased·15.92%, 19.76f, 10.16% and -1.63 % respectively. 4. Alkaline phosphatase activity in the jejunum, kidney, liver and serum of female mice for the 14 day treatment with ginseng extract(0.2 mg/10 g) was increased 18.89%, 24.55%, 16.97% and 27.59% respectively. 5. Increasing activity of the enzyme in the liver of both male and female mice for the 7 day treatment was declined to some extent at the 14 day treatment, on the other hand, increasing activity of the enzyme in the jejunum, kidney and serum of mice for the 7 day treatment was more promoted at the 14 day treatment. 6. The 7 day and 14 day treatment with ginseng extract increased 20.20% and 20.96% of inorganic phosphate phosphorus in male blood, 22.38% and 17.57f in female blood respectively. In accordance with the results mutual relationships of ginseng, internal secretion, nucleic acid and alkaline phosphatase activity were disscussed.