• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.3
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• pp.172-178
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• 2004

When soybean sprouts aye grown in the closed condition (where the ratio of $\textrm{O}_2$ and $\textrm{CO}_2$ is 7 ： 3), amount of $\textrm{CO}_2$ is increased and $\textrm{O}_2$ is decreased with the passage of time. At the same time, the amount of ethylene is automatically increased. By increasing the concentration of ethylene gas up to 0.5-1.0 ppm in the growth room, the length of sprouts was restricted to 6-7 cm and the thickness of sprouts was increased to 2.70$\pm$0.30 mm. The production of good quality sprouts which were fat and short was possible without application of any growth regulators such as indole-3-acetic acid known to have accumulation problem in humane body. To maintain the freshness during the transportation and prevent sprouts from rotting and bad smell at market, cold storage at 2-$5^{\circ}$ and airtightness which will restrict photosynthesis and respiration (higher than $10^{\circ}$) are needed. The freshness of sprouts is depended on the increase of $\textrm{CO}_2$ and the depletion of $\textrm{O}_2$ in the package. When the sprouts were stored below 1$0^{\circ}C$ (preferably below 8$^{\circ}C$), the concentration of $\textrm{CO}_2$ in the package remained below 30% for more than 60 hours, which was possible to keep sprouts in freshness without any offensive odor, But sprouts were maintained at $13^{\circ}$ for more than 25 hours, the concentration of $\textrm{CO}_2$ increased over 30% and produced an offensive odor. The little amount of $\textrm{O}_2$ gas was existing for 30 hours at $5^{\circ}$ but it was disappeared completely within 7 hours over $10^{\circ}$ and the sprouts became rot and produced severe offensive odor.

• The Korean Journal of Nuclear Medicine
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• v.35 no.5
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• pp.334-341
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• 2001

Purpose: Ascorbic acid us known to act as an antioxidant. Therefore, it can be used in increasing the efficiency of radiochemical labeling of Technetium-99m setamibi by inhibition of oxidation of $Sn^{2+}$ at low concentration. We intended to estimate the efficiency of radiochemical labeling and the stability of the newly formed formulation when ascorbic acid was added to a commercial kit. Materials and Methods: Synthesis of sestamibi was performed according to Dong-A's patent procedure (No.10-2001-0012877). First, we undertook a study to evaluate the efficiency of radiochemical labeling of sestamibi containing ascorbic acid. The stability of the vials was assessed using either $7.5{\mu}g\;or\;75{\mu}g$ of ascorbic acid, added to commercial vials under the accelerated condition(Temp : $40^{\circ}C{\pm}2^{\circ}C$, Relative humidity : $75{\pm}5%$). Results: Sestamibi was synthesized in overall 35-40% yield over 5 steps from a commercially available methallyl chloride as a starling material. When ascorbic acid was added, the efficiency of radiochemical labeling was maintained compared to the vial with no ascorbic acid. The accelerated test showed that the addition of ascorbic acid inhibited the oxidation of $Sn^{2+}$ ion by antioxidation mechanism. Also, the efficiency of radiochemical labeling of this vial after 9 months was nearly the same as the starting point. Therefore, the storage period of the kit is likely to be extended. Taken together, it suggests that the addition of ascorbic acid as a stabilizer is desirable. Conclusion: To increase the stability of a sestamibi cold kit, it is desirable to add ascorbic acid as a stabilizer to the commercial formulation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.11
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• pp.1678-1683
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• 2010

For extension of storage period of cabbage-kimchi, effects of heat treatment as well as nisin or yucca extract were examined on the growth of microbes. Firstly, when kimchi was heated at various temperatures in polyethylene plastic bottle or membrane pouch, the optimum inhibitory condition giving no sensory change was at $80^{\circ}C$ for 30 min in a plastic membrane pouch and this treatment made a reduction of $0.3\;log_{10}CFU/g$ in total microbes. The result showed that use of plastic bottle was inefficient due to low heat transfer rate. Interestingly, pasteurization of seasoning pastes at $80^{\circ}C$ for 30 min separately from cabbage resulted in better inhibitory effect reducing $0.5\;log_{10}CFU/g$ of total bacteria and $1.0\;log_{10}CFU/g$ of lactic acid bacteria, and this operation was regarded as a promising inhibitory method. Secondly, when nisin and yucca extract were separately added in kimchi, microbial growth was inhibited during storage period and their inhibition effects were enhanced at lower temperature.

• Korean Journal of Poultry Science
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• v.18 no.3
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• pp.183-196
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• 1991

In order to establish ELISA method to detect antibody against IBV various factors involved were examined. Antigen was prepared from Massachusetts type IBV which is known to be one of serotypes distributed most widely. The virus was grown in embryonated SPF chicken eggs. Allantoic fluid harvested was processed to ultracentrifugation and sucrose density gradient centrifugation to produce a purified antigen The antisera selected from the field samples based on hemagglutination inhibition test were used as the standard positive and negative sera for this study and the results obtained were summarized as follows. 1 , It was found that ELISA test was satisfactory when the purified antigen was coated on the plate in the amount of about 40ng protein per well. In case of the phospholipase treated hemagglutinating antigen it gave satisfactory results when the each well wns coated with 1.2 to 2.5 hemagglutinating unit which was equivalent to 40 to 90ng of protein. 2. There was no significant difference in the ratio of optical density of positive to that of negative serum whether the coated antigen was held for 1 hour at 37$^{\circ}C$ or it was held overnight at 4$^{\circ}C$. The coated antigen could be kept in dried state without change of antigenecity for at least one month of experimental period at 4$^{\circ}C$. 3. There was a big variation in the optical density and P/N values depending on the maker of the plates and on the plate of the same maker. 4. It was found that background optical density was negligible when serum was diluted more than 1：50 and serum dilution of 1：100 appeared to be appropriate as a routine test dilution to screen the antibody. 5. Optical density was fairly constant 15 minutes afterward from the time substrate was treated and during the 4 hours after stopper was treated. 6. There was a low correlation(r＝0.42) between ELISA and HI test. However, when 74serum samples were tested for the IBV antibody, 98.7% were found to be positive by both tests in which titers of 2$^{6}$ or more by HI test and P/N values of 1.4 or more by ELISA were considered to be positive, 7 Day-old IBV vaccinated chickens shows a similar antibody decay and rising pattern until 8 weeks of age by the two tests, ELISA and HI.

• Journal of Dairy Science and Biotechnology
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• v.24 no.1
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• pp.9-18
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• 2006

Total 150 packs of UHT milk and UHT-ESL milk, produced by different domestic milk companies, were compared at refrigerated and room temperature for 35 days in terms of microbiological qualities such as incidence date, number of incidence packs, and numbers of bacteria, and post-pasteurization contamination. Overall qualities of UHT-ESL milk were slightly better than that of UHT milk in relations to total bacteria in milk. No coliforms were detected in two groups of UHT milk samples after 35 days. Aerobic spores were more common in two brands of UHT milks stored in 20$^{\circ}$C than those in 7$^{\circ}$C, in which spores were broken out at 7 and 14 day. No incidences of thermoduric bacteria were founded until 14 days in two groups of UHT milks, but high level of counts (<300${\sim}$<3,000 CFU/ml) after 21 days at 20$^{\circ}$C and 40${\sim}$3,600 CFU/ml at 7$^{\circ}$C were detected, respectively. Psychrotrophic bacteria were higher in UHT milk than in UHT-ESL milk, in which began to detect at 28 days. No post-pasteurization contamination by salmonella spp. and staphylococcus aureus were found throughout the experimental periods. One may conclude that the shelf life of UHT milk under cold-chains system can be extended up to 21days, as long as UHT treated milk are filled in sterilized containers by aseptic packaging system.

• Journal of Food Hygiene and Safety
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• v.27 no.2
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• pp.161-168
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• 2012

This study was conducted to evaluate microbial contamination levels of Korea traditional rice cakes such as Sirutteok, Garaetteok and Gyeongdan in the manufacturing process and environment. The microbial contamination levels such as total aerobic bacteria, fungi, coliforms, Escherichia coli, Staphylococcus aureus, Bacillus cereus and Clostridium perfringens of rice cake products were analyzed. The contamination levels of total aerobic bacteria, coliforms, fungi and B. cereus in raw materials were in the range of 2.4~4.5, ND~1.9, 1.2~2.1 and 1.0~2.1 log CFU/g, respectively. The microbial contamination levels of total aerobic bacteria, coliforms, fungi and B. cereus in manufacturing process of rice cakes were increased in the soaking and grinding steps and were decreased in steaming step. E. coli, S. aureus and C. perfringens were not detected in any manufacturing process and environment. The microbial contamination levels of raw materials and final products of rice cake were suitable for microbial safety standard in Korea. However, the manufacturing environment such as equipments and employee's sanitation were in trouble for microbial safety. The results of this study suggest that safety educatio n for personal hygiene and safetymanagement in processing environment are continuously required to assure safety in working environment and employee's individual hygiene.

• Weed & Turfgrass Science
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• v.7 no.1
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• pp.35-45
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• 2018

The seaweed Ulva spp., which is frequently bloomed in coastal areas, have negatively affected on marine ecosystem and industrial activities. Therefore, many researches have been conducted to solve this problem in the worldwide. In this study, we carried out several experiments to develop the methods for effectively controlling Ulva growth through an alone or mixture application of chemical and temperature. Three chemical mixtures ($H_2O_2$+N-vanillylnonanamide; $H_2O_2$+nonanoic acid; $H_2O_2$+sodium citrate), those had a synergistic effect to the death of Ulva australis (ULAUS), were found out. On the other hand, the death of ULAUS was significantly enhanced and accelerated as some chemicals were briefly treated with warm water of $40^{\circ}C$ rather than $25^{\circ}C$, showing that peracetic acid 100 ppm, sodium percarbonate 100 ppm, and hydrogen peroxide 30 ppm has a better activity than that of sodium chlorite 200 ppm and menadione sodium bisulfite 4 ppm. In addition, a strong synergistic effect to the death of ULAUS thallus was also observed when the sodium citrate 1,000 ppm (pH 3.0) or acetic acid 200 ppm (pH 3.5) solution prepared in f/2 medium were treated in a short time at $40^{\circ}C$. However, an additive effect was only appeared as pH values of their solutions were increased to 8.0. Taken together, It seemed that our results could be developed as one of an eco-friendly practical measures useful for alleviating Ulva bloom in the future.

• Journal of Bio-Environment Control
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• v.24 no.1
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• pp.8-12
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• 2015

There are various limiting factors that take part in the production of daughter plants, but the important thing for mother plants of strawberries is to undergo a sufficient period of dormancy during winter. It is a well known fact that many runners and daughter plants are generated from mother plants that have been through sufficient cold treatment, but such researches were not found in Korea. This experiment was conducted due to the recent need for a research on the effects of cold treatment using 'Seolhyang,' 'Maehyang' and 'Ssanta' cultivars bred in Korea for two years in 2012 and 2013. The strawberries were divided into 4 types treatments: cold treatment plants in which 1,000 hours have passed in the temperature of $5^{\circ}C$ and below; cold+heated treatment plants in which 1,000 hours have passed in the temperature of $5^{\circ}C$ and below, and then 2 weeks in the greenhouse; greenhouse treatment plants raised in the greenhouse; and plants in harvest treatment. The results of the 2012 experiment showed that 'Seolhyang' had the bigger number of daughter plants in the cold, cold+heated, and harvest than greenhouse. 'Maehyang' had the biggest number of daughter plants in the cold+heated, and lowest in the greenhouse and harvest. 'Ssanta' had no significant difference in all treatments. The results of the 2013 experiment showed that 'Seolhyang' and 'Maehyang' both had more daughter plants in cold and cold+heated than in the greenhouse and harvest. 'Ssanta' tended to show a similar result and cold+heated had statistically more daughter plants than greenhouse.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.45 no.4
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• pp.399-408
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• 2019

Arbutin, which is used as a whitening ingredient, can produce hydroquinone, known as causing skin disease and carcinogen. Preservatives are essential to prevent microbial contamination during long-term storage and use of cosmetics, but safety issues such as toxicity and skin irritation are being raised. This study was conducted to determine hydroquinone and 21 preservatives levels in 40 arbutin-containing whitening functional cosmetics sold on-line and off-line. Result showed that 9 products contained hydroquinone. The concentrations in 7 products were ranged from 0.3 to 0.9 ppm, which were within the maximum allowed amount established by the Ministry of Food and Drug Safety. However, 2 products were 8.4 and 50.5 ppm and exceeded the allowed amount. Preservatives were detected 20 products. Detected items and ranges were phenoxy ethanol 0.1 ~ 0.7% (N = 15), Methyl paraben 0.19 ~ 0.21% (N = 2), Chlorphenesin 0.13% (N = 1), chlorhexidine 0.006% (N = 1), Propyl paraben 0.06% (N = 1), which were within maximum allowed amount established by the Ministry of Food and Drug Safety. Also, in cases of functional cosmetics the phrase "functional cosmetics" should be expressed on the primary or secondary package of cosmetics by cosmetics act. However, 1 product did not state the phrase as functional cosmetics. This study suggest that preservatives were safely managed. However, hydroquinone in hydroquinone-detected products could be produced by the decomposition of arbutin. Thus, further studies on the decomposition of arbutin are required to improve the quality control of the cosmetics.

• Journal of Food Hygiene and Safety
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• v.26 no.2
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• pp.182-185
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• 2011

This study was conducted to develop an appropriated management for safety of children snacks sold around school. Total 598 items as targeted food were collected; 66 biscuits, 320 candies, 57 chocolates, 40 ice creams and 115 beverages. Microbiological hazards such as total aerobic bacteria, Coliforms, Escherichia coli, Bacillus ceruse, Yeasts & molds were measured by analytical method in Korean food code. Total aerobic bacteria and Yeasts & molds were detected in cookies at the level of less than 2.69 and 2.65 $log_{10}$ CFU/g and the detection rates were 54.55 and 62.12%, respectively. Bacillus cereus was detected in 1 snack only at the level of 1.39 $log_{10}$ CFU/g but it was less than Korean microbial standards and specifications (3 $log_{10}$ CFU/g). Total aerobic bacteria and Yeasts & molds were detected in candies less than 2.86, 3.36 $log_{10}$ CFU/g and the detection rates were 46,8% respectively. Total aerobic bacteria, Yeast & mold were detected in chocolates at the levels less than 2.52 and 1.87 $log_{10}$ CFU/g and the detection rates were 33 and 22% respectively. Total aerobic bacteria in both ice creams and beverages were detected at the levels less than 3.39 and 1.35 $log_{10}$ CFU/g and the detection rates were 82 and 5% respectively. Coliforms were found in one ice cream (1.39 $log_{10}$ CFU/g) only. The result of this study indicated that all children snacks around school were suitable for microbial standard and specifications in Korean Food Code. However, since most children snacks around school are circulated without proper storage temperature and handing condition, consistent microbial management for children snacks are needed.