• 한국식품영양과학회지
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• 제28권5호
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• pp.1051-1057
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• 1999

The effects of gamma irradiation on taste compounds of low salted and fermented squid were investig ated. Salted and fermented squid products were prepared with salt concentrations of 5%, 10%, and 20% and was fermented at 15oC and 25oC after gamma irradiation with a dosage of 2.5~10 kGy. Amino nitrogen (AN), volatile basic nitrogen(VBN), trimethylamine(TMA), and hypoxanthine(Hx) contents were examined during the fermentation periods. Results showed that gamma irradiation had no effect on the initial con tents of AN, VBN, TMA, and Hx compared with non irradiated salted and fermented squid. During the fermentation periods, these contents rapidly increased in accordance with the decrease in NaCl concen tration and irradiation dose, and the increase in fermentation temperature. Specifically, the taste compounds of salted and fermented squid prepared with a NaCl concentration of 10% and an irradiation dose of 10 kGy maintained the appropriate level for the fermentation period at 15oC.

• 한국분말재료학회지
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• 제12권2호
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• pp.122-130
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• 2005

Layered silicate was synthesized at hydrothermal condition from silica adding to various materials. Nano-clay was synthesized by intercaltion of various amine compounds into synthetic layered silicate. The products were analysed by XRD, SEM, and FT-IR in order to examine the condition of synthesis and intercalation. From the results, it was confirmed that kaolinite was synthesized from precipitated silica and gibbsite at $220^{\circ}C$ during 10 days, and hetorite was synthesized from silica sol at $100^{\circ}C$ during 48 h. Na-Magadiite was synthesized from silica gel at $150^{\circ}C$ during 72 h, and Na-kenyaite was synthesized from silica gel at $160^{\circ}C$ during 84 h. Nano-clay was prepared using synthetic layered silicate intercalated with various amine compounds. Kenyaite was easily intercalated by various organic compounds, and has the highest basal-spacing value among other layered silicates. Basal-spacing was changed according to the length of alkyl chain of amine comopounds. Polymer can be easily intercalated by dispersion with large space of interlayer. Finally, epoxy/nano-clay nanocomposite can be easily prepared.

• 한국산업보건학회지
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• 제32권4호
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• pp.371-380
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• 2022

Objectives: To ensure that employers handling petroleum compounds understand whether petroleum-based UVCB (unknown or variable composition, complex reaction products, or biological materials) substances contain hazardous substances and comply with the Occupational Safety and Health Act, petroleum-based UVCB substances were analyzed and the results from samples were compared with MSDS (Material Safety Data Sheet) contents. Methods: Twenty-one petroleum samples were analyzed using GC-MS (Gas Chromatography-Mass Spectrometry), targeting ten volatile organic compounds regulated by the Occupational Safety and Health Act. Results: The target chemicals were detected in 13 out of 21 samples. All 13 samples were in the naphtha (low boiling point naphthas (gasolines)) group. There were also naphtha group samples containing 2% benzene. Some naphtha samples used as solvents contained about 1% benzene. Conclusions: This study shows that naphtha group petroleum substances contain hazardous chemicals in many cases. In particular, if benzene, n-hexane, and toluene with low occupational exposure limits are contained above the limit concentration. Such information should be delivered in the article on MSDS legal regulations.

• 한국식품저장유통학회지
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• 제19권5호
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• pp.757-766
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• 2012

향미가 우수한 100년 묵은 재래 간장에서 부터 강력한 항진균 활성(antifungal)균주를 분리 동정하여 Bacillus velelzensis SSH100-10으로 명명하였다. B. velezensis SSH100-10은 식품 위해 및 식품 변패곰팡이에 대한 항곰팡이 활성과 장류에 이취를 주는 산막효모 등에 대한 항효모 활성이 동시에 있으며, 강력한 단백분해활성을 나타내었다. NaCl 내염성도 우수하여 12% NaCl 농도하에서도 생육 48시간에 $A_{600}$에서 3.51의 생육도를 나타내었다. 또한 최근 Bacillus subtilis group 중 일부 균주에서 설사형 독소인 enterotixon을 나타내는 균주들에 대한 보고가 증가함에 따라, 안전성검증의 일환으로 enterotoxin 생성 여부를 조사하였을 때, 본 분리 균주는 enterotoxin 검지반응에서 음성을 나타내었다. B. velezensis SSH100-10이 생산하는 항진균 활성물질을 SPE, preparative HPLC, reverse phase-HPLC로 정제 후, MALDI-TOF-MS와 아미노산 조성 분석을 통하여 그 항진균 원인 물질이 $C_{14}$ iturin A와 $C_{15}$ iturin A 임을 구명하였다. 또한 B. velezensis SSH100-10의 배양상징액과 분리 정제된 항진균 물질 $C_{14}$ iturin A와 $C_{15}$ iturin A와 대조구로 시판되는 $C_{14{\sim}15}$ iturin A의 pH, 온도, 효소 안정성 실험을 통하여 B. velezensis SSH100-10은 pH, 열, 효소처리에 매우 안정한 iturin A 이외에도 pH에 불안정한 또 다른 구명되지 않은 항진균 물질을 생산함을 보고하였다. 본 연구에서 보고된 강력한 항진균 활성을 지니는 B. velezensis SSH100-10은 맛있는 발효과정의 종균으로서의 작용과 더불어 콩발효식품에서 유해요소가 될 수 있는 바람직하지 못한 미생물을 제어함으로서 콩발효식품의 안전과 위생수준을 개선할 수 있는 우수한 종균으로 활용될 수 있을 것이다.

• 한국식품과학회지
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• 제8권2호
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• pp.107-112
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• 1976

본(本) 실험(實驗)은 Gonda-type 치이즈의 숙성중(熟成中) casein의 변화(變化)를 구명(究明)하고자 총질소(總窒素), 수용성질소(水溶性窒素), 12% TCA 가용성질소(可溶性窒素) 및 5% NaCl 가용성질소(可溶性窒素)의 양(量)을 정량(定量)하여 비교(比較)하였고 또한 DEAE-cellulose column과 polyacryl amide gel electrophoresis를 사용(使用)하여 그 변화(變化)를 실험(實驗)한 결과(結果)는 다음과 같다. 1. 총질소중(總窒素中) 수용성질소량(水溶性窒素量)은 숙성(熟成) 2개월(個月)과 4개월(個月)에 각각 19.03% 및 30.61%이였으며, 12% TCA 가용성질소량(可溶性窒素量)은 각각 7.72% 및 11.73%이였다. 2. 5% NaCl 가용성질소량(可溶性窒素量)은 총질소중(總窒素中) 제조직후(製造直後)에 10.76%에서 숙성(熟成) 2개월(個月)에는 41.13%로 증가(增加)하였으나 숙성(熟成) 4개월(個月)에는 22.86%로 감소(減少)하였다. 3. 각종(各種) 질소화합물(窒素化合物)을 분가(分加)한 바 각각 모두 5개의 주(主) peak와 $3{\sim}4$개의 minor peak가 나타났으며 각 fraction의 면적비(面積比)가 숙성기(熟成期)에 따라서 증가 또는 감소를 나타내었다. 4. 4개월(個月) 숙성(熟成)된 치이즈를 전기영동(電氣泳動)한 결과(結果) 질소화합물(窒素化合物)에 따라서 $5{\sim}8$개의 band를 나타내었다. 5. 12% TCA에서 침전(沈澱)된 부분(部分)과 가용성(可溶性) 부분(部分)을 아미노산(酸) 조성(組成)을 분석(分析)한 바 모두 16개의 아미노산(酸)으로 나타났으나 조성(組成)의 비율(比率)은 서로 다르게 나타났다.

• Bulletin of the Korean Chemical Society
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• 제32권spc8호
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• pp.3022-3030
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• 2011

Since the discovery of the fact that compounds bearing a vinylic fluoride moiety often exhibit remarkable biological activities such as enzyme inhibitors, many synthetic methods for fluorine-substituted vinylic compounds have been developed. The synthesis of selectively fluorinated building blocks, such as arylsubstituted fluoro-alkenes, also has become an area of interest in recent years. Herein we describe a novel and practical method for the synthesis of 1,1-difluoro- and 1-fluoroalkenes starting from easily accessible trifluoroacetophenone derivatives. Various 1,1-difluoro- and 1-fluoroalkenes were prepared by the reaction of the corresponding tosyl hydrazones that were derived from trifluoroacetophenone derivatives by treating with alkyl or aryllithium reagents via addition-elimination and single electron transfer (SET) mechanism.

• Natural Product Sciences
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• 제16권4호
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• pp.223-227
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• 2010

The DNA Topoisomerase I (DNA Topo I) inhibitory effect of ten isolated compounds (1.10) from the leaf and stem of Vitis amurensis were examined. Among them, amurensin G (5) and r-2-viniferin (7) showed high potent inhibitory activity against DNA Topo I. DNA Topo I, an important target for anticancer drugs, can cause DNA breaks and play a key role during cell proliferation, transcription and repair. Thus, the results suggest that the selected compounds (5 and 7) from Vitis amurensis have a possibility as DNA Topo I-targeting anticancer agents.

• 한국주조공학회지
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• 제15권3호
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• pp.262-271
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• 1995

It is well known what is impossible to refine primary and eutectic Si simultaneously by addition of both Cu-P and Sr(or Na). Because of the formation of compound $Sr_3P_2(or Na_3P)$ in the melt, in the result, both effects disappear. In this study Al-Cu-P alloy that comprises AlP compounds inside is added in the melt with Sr simultaneously. As AlP compounds that act on nucleation sites of primary Si are not formed but added directly an the melt, it is difficult to form $Sr_3P_2$ by reaction with Sr. Therefore it is possible to refine primary and eutectic Si simultaneously in the general casting process by use of Al-Cu-P alloy and Sr.

• Natural Product Sciences
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• 제8권1호
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• pp.26-29
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• 2002

The MeOH extract of Sorbus commixta (Rosaceae) exhibited strong DPPH radical scavenging activity, and through activity-guided fractionation two antioxidant compounds were isolated and identified as $catechin-7-O-{\beta}-D-xylopyranoside$ (1) and $catechin-7-O-\;{\beta}-D-apiofuranoside$ (2) by physicochemical and spectrometric methods. To evaluate the antioxidant effect of these compounds, some in vitro tests, such as the DPPH radical scavenging activity test, the superoxide radical scavenging activity test and the lipid peroxidation inhibitory activity test, were performed. Compounds 1 and 2 showed stronger activities than both a-tocopherol and butylated hydroxy anisole (BHA) in each assay.

• 동의생리병리학회지
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• 제19권3호
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• pp.792-796
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• 2005

Disk assays on the compounds (10 and 12) showed both to have antifungal activity against the dermatophytic fungus Trichophyton mentagrophytes ATCC 28185, (1 and 3 mm inhibition zones at $60\;{\mu}g/disc$), but not against the Gram-positive bacterium B. subtilis or the Gram-negative bacteria Escherichia coli and Pseudomonas aeruginosa or fungi Cladosporium resinae and Candida albicans. However, the compound (13) did not show against antifungal activity. The geranyloxy compounds (10, 12, and 13) were cytotoxic to P388 murine leukaemia cells ATCC CCL 46 P388D1, ($IC_50$ >6,250 ng/mL at $7.5\;{\mu}g/disc$). These results suggest that The geranyloxy compounds possesses antimicrobial and antitumor activities.