• Korean journal of food and cookery science
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• v.13 no.4
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• pp.390-395
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• 1997

The inhibitory effects of cereal extracts and concentrates from barley, waxy rice flours and malt on enzymatic browning were measured using apple polyphenol oxidase (PPO). Malt concentrate showed the largest inhibitory effect on PPO among all. The relationship between the properties of malt concentrate such as browning intensity and reducing power and their inhibitory effect on PPO was also studied. As the heating time increased, the browning intensity and the reducing power of malt concentrates were increased, while PPO activities were decreased. Inhibitory effect of malt concentrates on PPO increased with heating time and their concentration. L-value and compression force of the apple slices dipped in malt concentrate decreased by 6.9% and 14.3%, respectively, showing the smallest changes compared with raw and water-dipped apple slices during cold storage for 9 days. These results suggest that malt concentrate can be a potential source for the control of enzymatic browning.

• Food Science of Animal Resources
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• v.38 no.5
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• pp.1029-1042
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• 2018

This study aimed to investigate the use of golden thread extract (GTE), clove extract (CE), and commercially available nitrite for retarding lipid and protein oxidation and for maintaining color stability and sensory attributes in beef patties stored at $4^{\circ}C$. GTE, CE, and nitrite treatment samples were found to be efficient in retarding lipid oxidation as all three treatments resulted in low thiobarbituric acid reactive substance (TBARS) content (p<0.05). By using GTE, CE, and nitrite into beef patties, protein oxidation was not developed. Incorporation of GTE and CE into beef patties maintained color stability by protecting against the decrease of $L^*$, $a^*$, $b^*$, chroma, and hue angle values and exhibited significant influence on sensory characteristics, including color and odor of beef patties (p<0.05). Compared to commercially available nitrite, GTE and CE were more effective as antioxidants for inhibiting lipid oxidation, and preserving color stability of fresh beef patties. The study indicated that GTE and CE could be utilized efficiently to extend the shelf life of beef patties.

• 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 Medicinal Crop Science
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• v.12 no.6
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• pp.494-499
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• 2004

A method for long-term conservation of somatic embryos of Eleutherococcus senticosos was described. Suspension cultured globular somatic embryos were successfully conservated for 36 months at $4^{\circ}C$. The embryos resumed growth within two weeks when returned to MS liquid medium containing $0.2\;mg/{\ell}$. 2,4-dichlorophenoxy acetic acid. The optimal condition for cell proliferation was achieved when somatic embryos cultured at $32^{\circ}C$ in 1/3 MS liquid medium, and about 1.2 g of embryogenic cell was induced from 150 globular embryos after 6 weeks of suspension culture. The embryogenic cells produced from these somatic embryos exhibited normal plant regeneration on auxin-free medium.

• The Korean Journal of Food And Nutrition
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• v.12 no.2
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• pp.133-141
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• 1999

Juice of Dongchime a Korean traditional vegetable food fermented with lactic acid bacteria has been traditionary used as broth for Naengmyon a Korean cold noodles with broth. This study was carried out to demonstrate the growth inhibition of two food born pathogens Listeria monocytogenes and Escherichia coli O157:H7 in Naengmyon-broth containing Dongchimi-juice fermented with high antibacterial lactic acid bacteria Lactobacillus homohiochii B21 and Leuconostoc mesenteroides C16. Naengmyon-broth were made with beef broth and Dongchimi-juice fermented with lactic acid bacteria and the changes in viable cell counts of the inoculated pathogens in Naengmyon-broths were investigated during storage at 2$0^{\circ}C$ and 1$0^{\circ}C$. In Naengmyon-broth of 100% Dongchimi-juice stored at 2$0^{\circ}C$ the numbers of Listeria monocyto-genes and Escherichia coli O157:H7 were rapidly decreased from 106CFU/ml to 106CFU/ml in 8 hours and 40 hours respectively. In Naengmyon-broth containing 50% Dongchimi-juice their numbers were also rapidly decreased though the decreasing rates were not so fast as those in 1005 Dongchimi-juice. In Naengmyon-broth containing 10% Dongchimi-juice the growths of the two pathogens were markedly inhibited compared with those in 100% beef broth though some growths were occurred in early phase. But in Naengmyon-broth of 100% beef broth their growths were very fast from early. Antibacterial ac-tivity of the Dongchimi-juice was more distinct at 2$0^{\circ}C$ than at 1$0^{\circ}C$ and was more active against Listeria monocytogenes than against Escherichia coli 157:H7.

• Applied Biological Chemistry
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• v.30 no.4
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• pp.328-334
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• 1987

The stability of lipids(Soybean oil & Ramyon lipid) by adding soybean products' extracts and Soybean, Soybean products was investigated, respectively. 1. Ethanolic extracts of defatted Soybean was very antioxidative in soybean oil. Soybean hot water extracts, defatted soybean water extracts and Soyprotein isolate water extracts possess antioxidative activities. But, Fresh Soybean cold extracts don't possess antioxidative activity. 2. The Oxidation of Ramyon Lipids (beef tallow) during storage at $45^{\circ}C$ incubator was effectively surpressed by addition of defatted Soybean hydrolyzate, tempeh (Defatted), Soy protein isolate hydrolyzate. The power of antioxidative activity is this order: Soy protein isolate hydrolyfate> Defatted Soybean hydrolyzate> BHA (200ppm)> Tempeh> Tempeh extracts> Defatted soybean.

• Journal of Food Hygiene and Safety
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• v.14 no.4
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• pp.422-427
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• 1999

Antimicrobial activity of Korean leek was effective on Staphylococcus aureus, Bacillus cereus, Bacillus subtilis, E. coli O157:H7, Pseudomonas fluorescens, Pichia membranaefaciens. Extract from raw Korean leek and that from frozen one showed antimicrobial activity; in contrast, extract stored frozen condition or extract from blanched one lost antimicrobial activity. Filtration, centrifugation, and vacuum concentration did not affect antimicrobial activity of the leek, nor did the changes in storage pHs. Addition of ground leek to soy milk, soy curd, and broth for cold noodle resulted in the prolonged shelf life by significantly reducing the number of viable cells.

• Ocean and Polar Research
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• v.33 no.3
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• pp.303-308
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• 2011

Polar psychrophiles which thrive under extreme conditions such as cold temperature, high salinity, and high dose ultraviolet light, emerge as novel targets for biotechnology. To prevent genetic drift and the possibility of contamination by subculturing, cryopreservation was employed for two psychrophilic microalgae, Porosira sp. (KOPRI AnM0008) and Pyramimonas sp. (KOPRI AnM0046), which have anti-freeze activities. Five cryoprotectants (dimethyl sulphoxide, ethylene glycol, glycerol, methanol and propylene glycol) showed toxicity at 20-30% (v/v). The optimal cryoprotectant concentration and equilibration time were less than 20% and 10 min, respectively. Cryopreservation was carried out in the presence of cryoprotectants either by direct freezing in liquid nitrogen ($LN_2$) or controlled freezing using a controlled rate freezer followed by storage in the $LN_2$ tank. As a result, Pyramimonas sp. (KOPRI AnM0046), a psychrophilic chlorophyta was revived. Cryopreserved Porosira sp. was not revived from either freezing protocols probably due to the silicic cell wall and its relatively large cell size. In the case of Pyramimonas sp. (KOPRI AnM0046), the controlled freezing method showed higher revival yield than the direct freezing method.

• Journal of Microbiology and Biotechnology
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• v.9 no.2
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• pp.213-218
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• 1999

Fructans are polyfructose molecules that function as nonstructural storage carbohydrates in several plants. In addition, it has been suggested that, due to their solubility, they can play an important role in helping plants survive periods of osmotic stress. In order to study the effect of levan synthesis on plant growth, the coding region of the levansucrase gene, which was isolated from Zymomonas mobilis, was introduced into tobacco plants using Agrobacterium tumefaciens-mediated transformation. The presence of the levansucrase gene in transgenic plants was verified by genomic DNA gel blot analysis. RNA gel blot and immunoblot analyses showed an accumulation of the corresponding transcript and protein product of the bacterial levansucrase gene in transgenic plants. Furthermore, a thin layer chromatography analysis revealed that fructans were synthesized and deposited in transgenic tobacco plants. When $T_1$ seeds were germinated and grown under polyethylene glycol-mediated drought stress or cold stress, the transgenic seedlings displayed a substantially higher level of growth than that of untransformed plants. These results suggest that fructans may playa significant role in the tolerance of plants under osmotic stress.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.53 no.3
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• pp.308-315
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• 2020

To obtain a value-added product from the non-toxic brown-backed toadfish Lagocephalus gloveri (pufferfish), we developed a retort pouched pufferfish soup (RPS) and characterized its processing conditions and quality metrics. We found that the most appropriate manufacturing process for the RPS consisted of detoxifying and cold-water dipping the pufferfish flesh, blanching it, and adding it to the retort pouch along with other ingredients (hot-water extract of pufferfish head and carcass, radish, bean sprouts, and garlic), after which the pouch was sealed, sterilized (120℃, F₀ value 7.5-10 min.), cooled, and inspected. The moisture, crude protein, and total volatile basic nitrogen contents of the RPS were 97.2%, 1.3% and 7.7 mg/100 g, respectively. The total free amino acid content was 903.2 mg/100 g, and the main free amino acids were glutamic acid, taurine, lysine, glycine, threonine, alanine, arginine, proline, and hydroxyproline. Sterilizing the RPS for up to F₀ value 10 min. did not cause any major problems in terms of chemical or sensory qualities. This RPS has good storage stability and organoleptic qualities compared with similar commercial pufferfish soups and is suitable for commercialization as a value-added instant seafood soup.