• Advances in nano research
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• 제14권2호
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• pp.201-210
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• 2023

A ZnO/poly (amide-imide) hybrid nanocomposite film with different weight percentages of Zinc oxide (ZnO) nanoparticles is synthesized and characterized in this paper. A two-step reaction successfully synthesized a new kind of heteroaromatic diamine with bulky pendant groups. In order to produce 3, 5-dinitro-3, 3-bis (4-(4-Nitrophenoxy) phenyl) -2- benzofuran-1-one, 3, 3'-bis (4-hydroxyphenyl) benzofuran-1-one and 3'-bis (4-hydroxyphenyl) benzofuran-1-one were combined with 3'-bis (3-hydroxyphenyl) benzofuran-1-one. The obtained dinitro was then reduced by zinc dust and hydrochloric acid. The reaction of 4, 4^* carbonyl diphthalic anhydride with amino acid L-alanine in acetic acid leads to the production of very high yields of chiral diacid monomer. As a result of the direct polymerization of these monomers, new optically active polymers were formed (amide-imide). In order to synthesize poly (amide-imide)/ZnO nanocomposites with different weight percentages (2, 4, 6, 8, and 10%), PAI and ZnO nanoparticles were combined using ultrasonication SEM, Fourier transform infrared spectroscopy, X-ray diffraction and thermal gravimetry were used to characterize the PAI films.

• Natural Product Sciences
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• 제29권2호
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• pp.59-66
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• 2023

The anti-melanogenic activity of 259 actinomycete strains was tested, and based on the results for the inhibition of mushroom tyrosinase activity and the reduction in melanin content, Micromonospora sp. JCS1 and JCS7 were selected as the strains with the highest anti-melanogenic potential. The activity-guided fractionation of extracts from JCS1 and JCS7 led to the isolation of the dipeptides cyclo(ʟ-Phenyl alanine (Phe)-ʟ-Proline (Pro)) (1) and cyclo(ʟ-Tryptophan (Trp)-ʟ-Proline (Pro)) (2). These two compounds were tested for their inhibition of mushroom tyrosinase by monitoring ʟ-DOPA levels and melanin production. Cyclo(ʟ-Phe-ʟ-Pro) (1) and cyclo(ʟ-Trp-ʟ-Pro) (2) were thus confirmed to have the potential for use in functional whitening cosmetics containing actinomycete-derived secondary metabolites.

• 한국미생물·생명공학회지
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• 제24권1호
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• pp.44-49
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• 1996

By using the ${\beta}$-tyrosinase of Citrobacter freundii KCT2006, which was cloned and overexpressed in Escherichia coli, 3,4-dihydroxy phenyl-L-alanine (L-DOPA) was synthesized efficiently from pyrocatechol, sodium pyruvate, and ammonium acetate. Optimal temperature and pH for the reaction were determined to be about 18$^{\circ}C$ and 8.5, respectively. The effects of substrate concentrations were also examined at different concentrations of ammonium acetate, sodium pyruvate, and pyrocatechol. Ammoniumacetate and sodium pyruvate increased the reaction rate until the concentrations reached to 300mM and 50mM, respectively. Although pyrocatechol showed the optimal concentration at 20mM, it was controlled between 20mM and 50mM to avoid the depletion of substrate during the enzymatic synthesis. Meanwhile the synthetic rate was improved about 20% when ethanol was included in the reaction solution. Based on above results, a reaction medium for the productin of L-DOPA was prepared and incubated with 1 unit/ml of ${\beta}$-tyrosinase. Pyrocatechol and sodium pyruvate was added to the reaction solutin intermittently to avoid the substrate depletion during the enzymatic reaction. After 24 hour of reaction, 31.6g/l of L-DOPA was accumulated in the reaction solution as soluble and precipitated ones and the conversion yield was about 85.2%.

• 한국식품영양과학회지
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• 제9권1호
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• pp.23-32
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• 1980

젓갈은 전통(傳統)있는 수산발효식품(水産醱酵食品)으로서 옛부터 즐겨 먹어온 우리나라 고유(固有)의 기호식품(嗜好食品)으로 널리 애용(愛用)되고 있으나 이들에 관(關)한 상세(詳細)한 연구(硏究)는 많지 않다. 본(本) 연구(硏究)는 전어내장(內臟)젓의 맛성분(成分)을 밝히기 위해 전어내장(內臟)젓 숙성(熟成)중의 유리(遊離)아미노산(酸), 핵산관련물질(核酸關聯物質), betaine, TMAO 및 TMA의 변화(變化)를 실험(實驗)하였다. 전어내장(內臟)젓 숙성(熟成)중 ATP, ADP, AMP 및 IMP는 감소(減少)하고 반면 hypoxanthine은 증가(增加)하여 숙성(熟成) 50일(日) 후에는 7.2u mole/g으로서 원료(原料)에 비(比)하여 2배(倍)나 증가(增加)하였다. 원료(原料)의 유리(遊離)아미노산조성(酸組成)을 보면 함량(含量)이 많은 것은 lysine, glutamic acid, valine, alanine, serine이며 함량(含量)이 적은 것은 arginine, phenyl-alanine, tyrosine이었고 cysteine 및 proline은 흔적량(痕迹量)에 불과(不過)하였다. 젓갈 숙성(熟成) 중 유리(遊離)아미노산(酸)의 양적(量的)인 변화(變化)는 있었으나 조성(組成)에는 변화(變化)가 없었고 대부분(大部分) 원료(原料)에 많았던 lysine, valine, glutamic acid, serine methionine, 등의 유리(遊離)아미노산(酸)이 젓갈중에도 함량(含量)이 많았으며 엑스분질소(分窒素)에 대한 유리(遊離)아미노산질소(酸窒素)의 비율(比率)은 50일간(日間) 숙성(熟成)시킨 젓갈이 가장 높았다. betaine은 젓갈의 숙성(熟成)과 더불어 계속해서 증가(增加)하여 숙성(熟成) 50일(日) 후에는 14.5mg%로서 원료(原料)에 비(比)하여 약(約) 4.5배(倍) 증가(增加)하였다. TMAO는 성숙(成熟) 50일(日) 후에 17.1mg%, TMA는 56.0mg%였다. 전어내장(內臟)젓의 맛성분(成分)으로서는 함량(含量)이 많은 lysine, valine, glutamic acid, leucine, methionine, serine, alanine, arginine 등의 유리(遊離)아미노산(酸)과 핵산관련물질(核酸關聯物質)로서는 hypoxanthine 등이 식염(食鹽)의 짠맛과 조합(組合)되어 전어내장(內臟)젓의 맛에 중요(重要)한 구실을 할 것이라고 추정(推定)된다.

• 한국수산과학회지
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• 제15권2호
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• pp.117-122
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• 1982

오분자기의 정미성분에 관한 자료를 얻고자 핵산관연물질, 유리아미노산, TMAO, TMA 및 총creatinine을 분석하였다. 핵산관련물중 AMP가 가장 많아서 $2.21{\mu}mole/g$이었으며 IMP와 inosine은 흔적량이었다. 유리아미노산중 함양이 많은 것은 taurine, arginine 및glycine으로 이들 3종 아미노산이 전유리아미노산의 $79.3\%$를 차지하였으며 tyrosine과 phenyl alanine은 흔적량이었다. TMAO, TMA 및 총 creatinine의 사양은 각각 $5.4mg\%,\;1.0mg\%$, 그리고 $5.0mg\%$ 였다. Omission test 결과 오분자기의 정미성분은 유리아미노산이 그 주체를 이루고 여기에 유기산과 핵산관련물질이 보조적인 역할을 하는 것으로 생각된다.

• 대한수의학회지
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• 제50권2호
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• pp.145-149
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• 2010

This study was carried out to find whether phenidone (1-phenyl-3-pyrazolidinone), a cyclooxygenase as well as a lipoxygenase inhibitor, exhibits the preventive effect on carbon tetrachloride $(CCl_{4})-induced$ acute liver injury in rats. Rats were pretreated with phenidone at a dose of 50 or 200 mg/kg (p.o.) once daily for 3 consecutive days before $CCl_{4}$ administration. Serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were measured. Malondialdehyde (MDA) production was determined as an index of lipid peroxidation in the liver and serum. The histopathological changes in the liver were also examined in each group. The reduction in body weights was significantly inhibited in the phenidone-treated group than in the $CCl_{4}$ control group. Significant increase in the relative liver weights of the phenidone-treated groups was observed compared with either the vehicle or $CCl_{4}$ groups. Elevation of serum AST and ALT activities occurred after $CCl_{4}$ treatment was significantly attenuated by the pretreatment with phenidone. The elevation of MDA levels in liver and serum were completely inhibited in phenidone-treated groups. The protective effects on phenidone-treated groups were confirmed histopathologically. These results suggest that phenidone may be a useful protector through modulation of hepatic inflammation in $(CCl_{4})-induced$ acute liver injury.

• 한국작물학회지
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• 제41권5호
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• pp.521-525
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• 1996

본 연구는 우리나라에 자생하는 전조의 근에 대한 조성분, 유리 아미노산, 향기성분 등의 분석을 통하여 향료작물로서의 가능성을 검토하고자 수행하였는 바 얻어진 결과를 요약하면 다음과 같다 1. 전조 뿌리의 조성분가운데 조단백질은 7.69%, 조지방 1.74%, 조섬유 2.44%, 그리고 조회분은 3.76% 였으며 엑스 함량은 27.68%로 나타났다. 2. 유리 아미노산 조성 및 함량에서 종류는 총 16종이었으며 아미노산의 함량에 따른 순위는 phenylalanine>tyrosine>arginine>alanine>glutamic acid>aspartic acid>lysine>isoleucine>proline>glycine>histidine>thereonine>leucine>methionine>valine, serine이었고 유리 아미노산 함량 중 가장 높은 아미노산은 phenylalanlne으로 6.38 mg이었다. 3. 전조의 뿌리에 대한 향기성분은 $\alpha$-pinene, d-1imonene 등의 mono terpene류가 11종이었고 methyl eugenol 등의 phenyl propanoid류가 3종, 기타 8종으로 구성되어 있었으며 식물정유의 수율은 0.58%였다. 4. 종합적으로 볼 때, 한국산 전조에 대한 향료작물로서의 가능성이 있을 것으로 판단되어 금후 향기성분의 수율을 높이기 위한 재배법 연구의 일환으로 차광, 재배거리, 시비량 등의 시험이 필요한 것으로 판단되었다.

• Journal of Preventive Medicine and Public Health
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• 제28권3호
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• pp.678-689
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• 1995

Chromium is one of the representative toxic substance by occupational exposure which damage the mucosa of respiratory tract including nasal septal perforation. The aim of this study is to evaluate the effect of chromium exposure on olfactory function and to obtain the fundamental information about chromium exposure. The authors performed olfactory function test, laboratory tests and questionnaire interview on the subject of three groups, that is, two exposed groups and one nonexposed group from May 1 to June 30, 1994. Exposed group 1 was 15 male workers without nasal septal perforation, exposed group 2 was 15 male workers with nasal septal perforation among 103 workers in 22 chromium plating factories, and nonexposed group was 15 male medical students. The gathered informations were histories of chromium exposure, habits of smoking and alcohol drinking, the concentrations of chromium in serum and urine, and asparate aminotransferase(AST), alanine aminotransferase(ALT), gamma-glutamyl transferase, etc. Olfactory function was checked by T and T olfectometer using phenyl ethyl alcohol(material A), methyl cyclopentenolone(material B), iso-valeric acid(material C), $\gamma$-undecalactone(material D), skatole(material E) and the results were expressed by detection threshold(DT) and recognition threshold(RT). There was a significant difference between exposed groups and nonexposed group in A, B, C, D, E substances by DT and in A, B, C, D substances by RT(P<0.01). The degree of olfactory dysfunction was highest in the exposed group 2 and lowest in the nonexposed group in all five substances by DT and it was same in A B, D substances RT and the difference of RT and DT. As summary, olfactory dysfunction by chromium exposure was recognized and the degree of olfactory dysfunction was higher in the exposed group with nasal septal perforation. Therefore, it would be helpful to apply olfactory function test for the early detection of olfactory dysfunction, and this test would be considered as the basic tool within workers' compensation system.

• 한국가금학회지
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• 제14권2호
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• pp.103-108
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• 1987

본 연구는 우모를 3가지 다른 방법으로 가공한 우모분과 생우모분, 그리고 시판 우모분에 대한 병아리 생체내의 아미노산 이용율을 조사하였다. 우모의 가공방법으로서는 증기가압 솥에서 2kg/$\textrm{cm}^2$ 압력에서 30분간 처리한 우모분, 3kg/$\textrm{cm}^2$ 압력에서 90분간 처리한 우모분, 4kg/$\textrm{cm}^2$에서 120분간 처리한 우모분, 시판하는 우모분 그리고 생우모분으로서 이들 우모분을 Abor Acre 계통 육용계 수컷 (체증100-140g)에 반정제 사료 형탸로 meal feeding하고 대사성과 내인성 배설물의 아미노산을 측정키 위해 무단백질 사료를 급여하였다. 가공된 우모분과 배설물들의 시료는 ion-exchange chromatography에 의해서 아미노산을 측정하여 아미노산 조성과 아미노산 이용율을 결정하졌는데 그 결과는 다음과 같이 요약된다. 1. 증기가압처리의 증가에 따라 우모분의 cystine 함량이 현저히 감소하였으나 다른 아미노산은 변화가 없었다. 2. 아미노산 이용율에 있어서는 생우모분, 2kg/$\textrm{cm}^2$ 압력에서 30분처리 우모분, 시판 우모분, 4kg/$\textrm{cm}^2$ 압력에서 120분처리 우모분, 그리고 3kg/$\textrm{cm}^2$ 압력에서 90분간 처리 우모분이 각각 -3.09%, 63.28%, 67.46%, 71.22%, 그리고 73.75% 순위로 높았다. 3. 필수 아미노산의 평균 이용율에 있어서는 생우모분, 2kg/$\textrm{cm}^2$ 압력에서 30분처리 우모분, 시판 우모분, 4kg/$\textrm{cm}^2$ 압력에서 120분처리 우모분 3kg/$\textrm{cm}^2$ 압력에서 90분처리 우모분이 각각 2,55%, 66.78%, 66.89%, 72.56%, 73.62% 순위로 높았다. 4. 중기가압처리 우모분과 시판우모분의 개별 아미노산 이용율에 있어서는 methionine, phenyl-alanine, leucine, arginine, threonine, isoleucine순위로 높았으나 histidine, lysine, aspartic acid는 이용율이 낮았다. 이상의 결과로서 3kg/$\textrm{cm}^2$ 압력에서 90분처리 우모분은 아미노산 이용율이 우수함을 알 수 있었다.