• Journal of Soil and Groundwater Environment
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• v.11 no.5
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• pp.43-50
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• 2006

Bioreporter bacteria, such as recombinant bioluminescent bacteria, have been used for the detection of specific compounds in complex environmental media. In this study, optimum conditions for the preparation and application of deep-freezed and Iyophilized recombinant bioluminescent strain KG1206 were investigated for the future application on contaminated environmental sites. Genetically engineered microorganism, Pseudomonas putida mt-2 KG1206, contains TOL plasmid and the plasmid inserted $P_{m}$, promoter on the upper part of lux gone in vector pUCD615, and m-toluate and benzoate are considered direct inducers for bioluminescence. Optimum conditions determined for the preparation and application of the deep-freezed and lyophilized strain were followings: cryoprotective agent (24% sucrose), lyophilization time (12 hrs), strain concentration ($OD_{600}=0.6$), reconstitution for freezed strain (quick reconstitution at $35^{\circ}C$), reconstitution for lyophilized strain ($3{\sim}6$ hrs exposure on LB medium), carrying conditions (keep at $20^{\circ}C$ after reconstitution). These results demonstrate the feasibility of deep-freezed or lyophilized state of genetically engineered bioluminescent strain for environmental usage.

• Journal of fish pathology
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• v.22 no.3
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• pp.335-342
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• 2009

The stability of immunoglobulin M (IgM) on different serum storage conditions and specific antibody response were tested using the serum collected from sevenband grouper Epinephelus septemfasciatus by enzyme-linked immunosorbent assay (ELISA). To test the effect of storage temperature and duration, sevenband grouper antiserum against bovine serum albumin (BSA) was stored at -80, -20 or 4${^{\circ}C}$ for 1, 34, 61 or 119 days. In addition, to test the effect of repeated freeze-thawing condition, the anti-BSA fish serum was frozen at -20 and -80${^{\circ}C}$ and then thawn and frozen for 1, 5 or 10 times repeatedly. Consequently, no significant difference was found in ELISA optical density (O.D.) values of sera for the above mentioned storage conditions: different temperatures (-80, -20 and 4${^{\circ}C}$), durations of storage (1, 34, 61 and 119 days), and repeated thaw-freeze cycles (1, 5, and 10 times), indicating that IgMs of test fish were stable. The specific antibody response of sevenband grouper was observed after BSA-immunization of the test fish reared at 20 ${^{\circ}C}$ or 25${^{\circ}C}$. At the rearing temperature of 20${^{\circ}C}$, the specific antibody against BSA first appeared at 14 days and maximum antibody titer was observed between 21 and 28 days, while at the rearing temperature of 25 ${^{\circ}C}$, specific antibody appeared at 7 days and maximum antibody titer was observed between 14 and 21 days. In conclusion, the rearing temperature at 25${^{\circ}C}$ gave a faster and higher specific antibody response than at 20${^{\circ}C}$ and the specific antibody response maintained for approximately 2 months at 20℃ and 25${^{\circ}C}$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.5
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• pp.770-774
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• 2002

The effect of mixing ratio of materials and their retort processing conditions on the physical properties and preference of oyster porridge were investigated. Rice gave adequate viscosity (about 800 cp) to the porridge as it was used 10～12% level and half of it was ground. Potato starch, waxy corn starch, and Perfectamyl AC showed small variation in viscosity unrelated to the temperature, that was a good condition for high quality porridge. Especially, waxy corn starch had a good property for retort porridge because its viscosity was maintained high during the processing and decreased to preferable one after processing. Purity CSC, modified starch gave gum-like texture and didn't cause water-separation much after freezing and thawing treatment of the porridge. Therefore, it was good for enhancing the physical property of the porridge as a co-additive of waxy corn starch when it was used at quarter level of waxy corn starch. Xanthan gum increased dispersibility of materials and it was useful for stabilizing physical quality of the porridge without affecting preference when it was used below 0.2% concentration. As a result, the optimal material-mixing ratio was determined as rice 10% (50% of it was ground), waxy corn starch 1.5%, Purity CSC 0.5%, xmthan gum 0.2%, salt 0.3%, and water 87.5%. Oyster's porridge, retort processed with this recipe, showed stable physical property after 6 month storage at room temperature.

• Korean Journal of Plant Resources
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• v.14 no.3
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• pp.251-258
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• 2001

Predehydration effects for cryopreservation in -196$^{\circ}C$ liquid nitrogen were studied in Korean native Aquilegia buergeriana var. oxysepala Kitamura and A. flabellata var. pumila Kudo seeds. Aquilegia species seeds were adjusted to moisture contents between 3.2 and 9.7% by air dry treatments. Seeds were placed in paper envelopes after submerged in liquid nitrogen and rewarming in 38 $^{\circ}C$ water. Seeds moisture contents by duration of drying were identified as controlling factors in the survival of Aquilegia species seeds for cryopreservation. Aquilegia species seeds having approximate 5% moisture content were able to withstand cooling to -l96$^{\circ}C$. Undehydrated seeds of Aquilegia buergeriana var. oxysepala Kitamura after being cryopreservated in liquid nitrogen have a 10.9% of moisture content and show 52.5% in germination. But, Aquilegia buergeriana var. oxysepala Kitamura seeds dehydrated by drying for 60 min. to have 6.0% of moisture content before cryopreservation show 84.7% in germination test. Properly dehydrated seeds after being stored in liquid nitrogen showed over 60% in germination rate and also shows an uniform sprouting time,11~13 days in average. Any morphologically deformity in germinating beds has not been observed. Results from this study suggest that Aquilegia species seeds can cryopreservation in liquid nitrogen if the seed moisture content is controled by a proper amount of dehydration.

• Journal of Applied Biological Chemistry
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• v.54 no.2
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• pp.108-113
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• 2011

The tyrosinase inhibitory activity of extracts from Phellodendron amurense was examined. Tyrosinase inhibitory activity of 60% ethanol extracts was determined as 25% and the inhibitory activity of 60% ethanol extracts against melanin biosynthesis in melanoma cell (B16F10) was 31.2%. The purified inhibitory compounds against tyrosinase by Sephadex LH-20, MCI-gel CHP-20 column chromatography from P. amurense was confirmed as obacunone by $^1H$-NMR, $^{13}C$-NMR and Fast atom bombardment (FAB)-Mass spectrum. The tyrosinase inhibitory activities of purified obacunone was respectively as 35.1%. The safety of essence with tyrosinase inhibitory compounds from P. amurense was also assayed by various safety profiles. First, pH and viscosity change of essence for 60 days were not detected. The essence also showed the stability against temperature and light for 60 days. All these findings suggest that extracts from P. amurense has a great potential as a cosmeceutical ingredient, which has a potent whitening effect.

• The Korean Journal of Food And Nutrition
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• v.10 no.3
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• pp.287-294
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• 1997

When bread making, the condition of thawing-fermentation for frozen dough were tested in variable temperature, and measured thawing-fermentation time and volume of frozen dough. L-Ascorbic acid (L-Aa) was added in frozen dough for the comparison test of develop volume in bread staling degree of baking bread were measured additive frozen dough which was stoppages in freezing, staling degrees were tested hardness with Rheometer. The test for comparison of thawing-fermentation time in variable temperature was shown the condition of dough conditioner at 3$0^{\circ}C$ was most effective for bread making, Because That condition was required very short time(74 min) But, in this comparison of volume in final products was shown the products in the condition of thawing-fermentation at 3$0^{\circ}C$ was smaller than the products at 5$^{\circ}C$(418 ml). The baking volume of L-Aa additive frozen dough which has under gone thawing-fermentation at 3$0^{\circ}C$, were shown baking volume of 420 ml in 2 weeks storage terms to 100 mg/kg L-Aa additive dough and shown baking volume of 454 ml in 4 weeks storage terms to dough of 200 mg/kg additive weight. Staling degrees of L-Aa additive frozen bread were measured with Rheometer. The hardness of 100 mg/kg L-Aa additive frozen bread was sown low level hardness in 1~2 weeks freezing term, 150 mg/kg L-Aa additive frozen bread was shown low level hardness in 3 weeks freezing term. In 4 weeks freezing term, 200 mg/kg L-Aa additive frozen bread was shown low level hardness compared with non-additive L-Aa frozen bread. In comparison of frozen bread quality, non-additive L-Aa products was better than additive L-Aa products in equality of baking shape and external apparence. But in total quality in external and internal apparence, additive L-Aa products was better than non-additive L-Aa products.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.04a
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• pp.82-82
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• 2019

종자은행은 종자를 보존하는 가장 경제적이고 효율적인 보전방법이지만, 수종에 따라 저장특성의 차이가 커서 수종별 저장방법의 확립이 필요하다. 초저온저장 방법은 세포 분열, 대사 작용을 정지 상태로 유지하므로 현재까지 장기간 보존을 위한 비용이 효율적이며 안정적인 방법이다. 공시재료는 멸종위기 야생식물 등 22종을 대상으로 하였다. 액체질소에 7일간 종자를 침지한 후 $37^{\circ}C$ 항온수조에서 10분간 해동하였다. 휴면이 있는 수종은 파종 전 종자를 저온습윤 하였고, 저온습윤 처리 후에도 휴면타파 되지 않는 수종은 농황산, 지베렐린을 개별 또는 혼용으로 처리하였다. 발아 및 유묘 평가는 $25^{\circ}C/20^{\circ}C$(광12h/암12h)조건에서 진행하였으며, 매일 28일차까지 발아조사를 수행한 후 평가하였다. 진달래속의 꼬리진달래와 철쭉이 초저온 민감성을 보였으며, 오리나무속의 물오리나무, 사방오리는 부분 민감성을 보였다. 민산초나무는 지하부건물중이 유의하게 감소한 결과를 보였으며, 이외의 수종은 초저온 민감성을 보이지 않았으므로 장기보존을 위한 초저온 동결보존이 가능한 것으로 보였다.

• Korean Journal of Food Science and Technology
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• v.49 no.1
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• pp.85-89
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• 2017

This study was conducted to prevent hardened texture in retorted frozen seafoods such as small octopus, squid, and top shell by adding sorbitol; the strength of mechanical hardness and other qualities were measured. The hardness of the 3 kinds of seafood pretreated with 2-4% (w/w) sorbitol solution decreased by 9-36% compared to the control. The hardness of retorted frozen octopus, squid, and top shell treated with sorbitol solution upon freezing significantly decreased to 1670, 1015, and $521g_f/cm^2$ compared to levels in untreated food of 1841, 1291, and $815g_f/cm^2$ (p<0.05), respectively. Yields based on weight in retorted seafood treated with sorbitol were increased by 2-5% compared to untreated samples. Additionally, the overall preference of texture was 0.4 points higher than that of control samples in descriptive sensory evaluation (p<0.05). The tissue softening of pretreated seafood was based on decreased dewatering due to the formation of small ice crystals during freezing as a result of sorbitol treatment.

• Korean Journal of Food Science and Technology
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• v.43 no.4
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• pp.426-431
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• 2011

In this study, we set an optimum blanching condition as a pretreatment condition to freeze welsh onion (Allium fistulosum L.) for the purpose of preserving the cooking material for long-term usage. With higher blanching temperature and longer processing time, the Hunter color values and the hardness of welsh onion tended to decrease, which confirmed softening of the tissue. Compared to before blanching, total bacterial counts decreased to near 2 log scale, whereas coliforms were not detected or decreased to a 1-2 log scale. Blanching by heating at 100$^{\circ}C$ for 5 min decreased peroxidase inactivity to more than 94%, whereas only 47% of the inactivity was achieved at 80$^{\circ}C$ for 1 min. The sensory evaluation for the blanched and defrosted welsh onion showed that the group blanched at 80$^{\circ}C$ for 1 min was preferred significantly (p<0.05).

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.10
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• pp.1475-1483
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• 2006

This study was carried out to examine the optimum processing conditions of seasoned semi-dried oyster, and to investigate its food component characteristics. Three types of semi-dried oyster were prepared: semi-dried oyster prepared without seasoning and coating (C), seasoned semi-dried oyster without coating (S) and seasoned semi-dried oyster coated with alginate (SA). SA was high in moisture (48.6%), while low in lipid (2.8%), and crude protein (25.9%) compared to those of C and S. Hardness and sensory scores of SA were $209.8g/cm^2$ and $3.9\sim4.5$ points, respectively. Total amino acid content (24,299 mg/100 g) of SA was lower than that (27,181 mg/100 g) of C, and the major amino acids were aspartic acid, glutamic acid, leucine and Lysine. The major fatty acids of SA were 16:0 (25.5%) as saturates and EPA (23.5%) and DHA (9.3%) as polyenes. Calcium and phosphorus contents of SA were 42.6 mg/100 g and 245.5 mg/100 g, respectively.