• Preventive Nutrition and Food Science
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• v.1 no.2
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• pp.252-255
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• 1996

As an index of freeze-injury of yeast, the leakage of intracellular substances from yeast cells after freeze-thawing was investigated. It was found that much more ultraviolet-absorbing substances leaked out from non-freeze tolerant yeast (NETY) than from freeze-tolerant yeast. Furthermore, the rate of leakage of cellular substances form NFTY during incubation exceeded that of FTY, indicating that NFTY is more susceptible to freeze-injury than FTY during frozen-storage. An apparent degradation of phospholipid was observed during incubation of perfermented frozen-cells of NFTY, while little change of phospholipid occurred in FTY, These results suggested that the difference in the sensitivity of yeast might be due to the strength of cell membrane in terms of the degradation of phospholipid by enzymes, phospholipases, attached to cell membranes.

• Journal of Microbiology and Biotechnology
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• v.21 no.9
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• pp.954-959
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• 2011

There have been a number of studies conducted in order to compare the efficiencies of recovery rates, utilizing different protocols, for the isolation of L. monocytogenes. However, the severity of multiple cell injury has not been included in these studies. In the current study, L. monocytogenes ATCC 19112 was injured by exposure to extreme temperatures ($60^{\circ}C$ and $-20^{\circ}C$) for a one-step injury, and for a two-step injury the cells were transferred directly from a heat treatment to frozen state to induce a severe cell injury (up to 100% injury). The injured cells were then subjected to the US Food and Drug Administration (FDA), the ISO-11290, and the modified United States Department of Agriculture (mUSDA) protocols, and plated on TSAyeast (0.6% yeast), PALCAM agar, and CHROMAgar Listeria for 24 h or 48 h. The evaluation of the total recovery of injured cells was also calculated based on the costs involved in the preparation of media for each protocol. Results indicate that the mUSDA method is best able to aid the recovery of heat-injured, freeze-injured, and heat-freeze-injured cells and was shown to be the most cost effective for heat-freeze-injured cells.

• Korean Journal of Plant Tissue Culture
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• v.27 no.4
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• pp.339-343
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• 2000

When plants are exposed to subfreezing temperatures ice crystals are forming within extracelluar space in leaves. The growth of ice crystal is closely related to the degree of freezing injury. It was shown that an antifreeze protein binds to an ice nucleator through hydrogen bonds to prevent growth of ice crystal and also reduces freezing damage. The antifreeze proteins in plants are similar to PR proteins but only the PR proteins induced upon cold acclimation were shown to have dual functions in antifreezing as well as antifungal activities. Three of the genes encoded for CLP, GLP, and TLP were isolated from barley and Kentucky bluegrass based on amino acid sequence revealed after purification and low temperature-inducibility as shown in analysis of the protein. The deduced amino acid of the genes cloned showed a signal for secretion into extracellular space where the antifreezing activity sup-posed to work. The western analysis using the antisera raised against the antifreeze proteins showed a positive correlation between the amount of the protein and the level of freeze tolerance among different cultivars of barely. Besides it was revealed that TLP is responsible for a freeze tolerance induced by a treatment of trinexapac ethyl in Kentucky bluegrass. Analysis of an overwintering wild rice, Oryza rufipogon also showed that an acquisition of freeze tolerance relied on accumulation of the protein similar to CLP. The more direct evidence for the role of CLP in freeze tolerance was made with the analysis of the transgenic tobacco showing extracellular accumulation of CLP and enhanced freeze tolerance measured by amount of ion leakage and rate of photosynthetic electron transport upon freezing. These antifreeze proteins genes will be good candidates for transformation into crops such as lettuce and strawberry to develop into the new crops capable of freeze-storage and such as rose and grape to enhance a freeze tolerance for a safe survival during winter.

• Korean Journal of Environmental Agriculture
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• v.33 no.4
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• pp.403-408
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• 2014

BACKGROUND: Kiwifruit is a warm-temperate, deciduous fruit tree. It is sensitive to frost or freeze damage during winter. Therefore, the farmers cover kiwifruit trunk with rice straw to preclude freeze injury. This study was conducted to evaluate trunk wraps for protection of freeze injury of kiwifruit (Actinidia deliciosa) vines. METHODS AND RESULTS: The experimental orchard was located in Sacheon (lat. $34^{\circ}56'N$, long. $128^{\circ}03'E$) of Gyeongsangnam-do, South Korea. The vines were 5-6-year-old 'Hayward'. Two wrap materials, rice straw and silver-cushioned mat (reflective foil-coated, plastic-foamed mat, Ganan Industry, Rep. of Korea) were evaluated for their heat-retaining ability. The trunks of kiwifruit vines were wrapped in late December, and the wraps were removed in mid-April the following year (2012/13 and 2013/14). Temperature inner wraps were recorded from January to March in 2013 and 2014 by WatchDog 2450 (Spectrum Technologies, Inc., USA). In 2013, the lowest ambient temperature of January and February was $-10.2^{\circ}C$, $-10.9^{\circ}C$, respectively. The lowest temperature of inner-wrap of silver -cushioned mat was $-6.3^{\circ}C$, $-2.6^{\circ}C$ in January and February, respectively. However, rice straw showed $-9.8^{\circ}C$ and $-9.9^{\circ}C$ in its lowest value of January and February. And also silver cushioned mat appeared to be superior to rice straw in its ability of heat-retaining during night time.

• Korean journal of food and cookery science
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• v.11 no.1
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• pp.9-12
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• 1995

The molar ratio of sterol to phospholipid differed from yeast strains, and the ratio was relatively higher in non-freeze-tolerant yeast strain, S. cerevisiae than freeze-tolerant yeast strains, D$\sub$2-4/ or CFY. Phospholipid composition of these yeast were also investigated. Phosphatidylcholine content was larger among phospholipids in all yeasts. Higher ratio of PC/PE was found in freeze-tolerant yeast than non-freeze-tolerant yeast. Higher proportion of linolein acid(18 : 2) against total fatty acid attached to phospholipid was observed in D$\sub$2-4/ than S. cerevisiae or CFY, and the degree of unsaturation of fatty acid was higher in D$\sub$2-4/ and CFY than in S. cerevisiae. These results suggested that the fluidity of yeast cell membrane was different in yeast strains, which might result in the difference in freeze-injury of yeast at low temperatures.

• Korean Journal of Agricultural and Forest Meteorology
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• v.11 no.4
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• pp.213-220
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• 2009

In order to predict the risk of freeze injury for 'Changhowon Hwangdo' peach trees, we used the dormancy depth (i.e., the daily chill unit accumulation during the overwintering period) as a proxy for the short-term, physiological tolerance to freezing temperatures. A Chill-days model was employed and its parameters such as base temperature and chilling requirement were optimized for peach trees based on the 12 observational experiments during the 2008-2009 winter. The model predicted the flowering dates much closer to the observations than other models without considering dormancy depth, showing the strength of employing dormancy depth into consideration. To derive empirical equations for calculating the probabilistic freeze risk, the dormancy depth was then combined with the browning ratio and the budburst ratio of frozen peach fruit branches. Given the exact date and the predicted minimum temperature, the equations calculate the probability of freeze damages such as a failure in budburst or tissue browning. This method of employing dormancy depth in addition to freezing temperature would be useful in locating in advance the risky areas of freezing injury for peach trees production under the projected climate change.

• Korean Journal of Agricultural and Forest Meteorology
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• v.11 no.4
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• pp.221-232
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• 2009

The geographical distribution of freeze risk determines the latitudinal and altitudinal limits and the maximum acreage suitable for fruit production. Any changes in its pattern can affect the policy for climate change adaptation in fruit industry. High-definition digital maps for such applications are not available yet due to uncertainty in the combined responses of temperature and dormancy depth under the future climate scenarios. We applied an empirical freeze risk index, which was derived from the combination of the dormancy depth and threshold temperature inducing freeze damage to dormant buds of 'Changhowon Hwangdo' peach trees, to the high-definition digital climate maps prepared for the current (1971-2000), the near future (2011-2040) and the far future (2071-2100) climate scenarios. According to the geospatial analysis at a landscape scale, both the safe and risky areas will be expanded in the future and some of the major peach cultivation areas may encounter difficulty in safe overwintering due to weakening cold tolerance resulting from insufficient chilling. Our test of this method for the two counties representing the major peach cultivation areas in South Korea demonstrated that the migration of risky areas could be detected at a sub-grid scale. The method presented in this study can contribute significantly to climate change adaptation planning in agriculture as a decision aids tool.

• Journal of Food Hygiene and Safety
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• v.3 no.1
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• pp.19-26
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• 1988

Most of meat spoilage bacteria area Gram negative, which are very sensitive to freezing ; for instance , 90% of E. coli cells are killed or sub-lethally injured by freezing at -3$0^{\circ}C$, and the freeze-injury rate is dependent upon freezing rate. Since the injured bacterial cells are sensitive to selective agents, they fail to multiply in selective media. Injured bacterial cells are, however, capable of spontaneous repair at appropriate environmental and nutritional conditions . Enumeration of injured bacterial cells involves artificial induction of repair at these conditions. Cubic beef samples(3$\times$3$\times$3cm) were frozen at -6$0^{\circ}C$, -4$0^{\circ}C$, or -18$^{\circ}C$. The samples frozen at each temperature were thawed at 4$^{\circ}C$, 2$0^{\circ}C$, or by microwave . After these respective freezing an thawing treatments, the percentage of sub-lethally injured total coliforms out of total surviving ones was measured and compared. The results were as follows: 1. The interaction between freezing and thawing on injury rate was not significant. 2. The injury rates(as means of all three thawing treatments post-freezing) by freezing at -6$0^{\circ}C$, -4$0^{\circ}C$, or -18$^{\circ}C$ were 32.2$^{\circ}C$ and 19.2$^{\circ}C$ respectively . 3. The injury rates(as means of all three freezing treatments)by thawing at 4$^{\circ}C$, 2$0^{\circ}C$, or by microwave were 49.3%, 11.7% and 21.0% respectively. The highest injury rate was caused by freezing at -6$0^{\circ}C$ and subsequent thawing at 4$^{\circ}C$. However since the injury rates by freezing treatment were not significantly different, freezing at -18$^{\circ}C$ and subsequent thawing at 4$^{\circ}C$ can also be recommended , from an economic perspective.

• Archives of Pharmacal Research
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• v.27 no.11
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• pp.1136-1140
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• 2004

Red ginseng and fermented red ginseng were prepared, and their composition of ginsenosides and antiischemic effect were investigated. When ginseng was steamed at 98-$100{\circ}C$ for 4h and dried for 5h at $60{\circ}C$, and extracted with alcohol, its main components were ginsenoside $Rg_3$ > ginsenoside $Rg_1$> ginsenoside $Rg_2$. When the ginseng was suspended in water and fermented for 5 days by previously cultured Bifidobacterium H-1 and freeze-dried (fermented red ginseng), its main components were compound K > ginsenoside $Rg_3{\geq}$ ginsenoside $Rg_2$. Orally administered red ginseng extract did not protect ischemia-reperfusion brain injury. However, fermented red ginseng significantly protected ischemica-reperfusion brain injury. These results suggest that ginsenoside Rh2 and compound K, which was found to be at a higher content in fermented red ginseng than red ginseng, may improve ischemic brain injury.

• International Journal of Industrial Entomology and Biomaterials
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• v.35 no.2
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• pp.123-128
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• 2017

Hangover due to alcohol consumption causes social and physical problems. There is a growing interest in edible insects worldwide. We have previously published a new technology to make hard mature silkworm, Bombyx mori, into edible form, steamed and freeze-dried mature silkworm larval powder (SMSP). In this study, AIN-76 or SMSP (0.1 and 1 g/kg rat body weight) containing diets in SD rats were pretreated for 2 weeks, and ethanol (3 g/kg rat body weight) was administered as an oral gavage and sacrificed after 3 hours. As a result, blood alcohol and aldehyde levels were significantly decreased in SMSP fed rats. In addition, liver injury markers, alanine aminotransferase (ALT) and alkaline phosphatase (ALP) were significantly decreased in SMSP group compared to ethanol group. $TNF-{\alpha}$, an inflammatory cytokine, and malondialdehyde (MDA), an oxidative stress marker, also showed a dose-dependent decrease in the group receiving SMSP. Conclusively, consumption of SMSP not only reduced hangover induced by ethanol, but also decreased liver damage, oxidative stress, and inflammatory response.