살 오징어(Todarodes pacificus) 간췌장 유래 한외여과 Aminopeptidase Retentate Fraction의 특성과 쓴맛 개선효과

김진수 ( Jin-soo Kim ),이정석 ( Jung Suck Lee ),윤인성 ( In Seong Yoon ),강상인 ( Sang In Kang ),박선영 ( Sun Young Park ),정우철 ( U-cheol Jeong ),허민수 ( Min Soo Heu ) 한국수산과학회(구 한국수산학회) 2020 한국수산과학회지 Vol.53 No.1

This study investigated some enzymatic properties and bitterness improvement of an aminopeptidase retentate fraction (ARF) from common squid Todarodes pacificus hepatopancreas extract (HPE), obtained by ultrafiltration with a 10 kDa molecular weight cut off membrane. Endoprotease and aminopeptidase (AP) activity, and the purity of the ARF (>10 kDa) increased by 6.69-18.11 U/mg and 1.5-2.6 fold, respectively, compared to HPE (2.63-9.37 U/mg). The AP activity toward LeuPNA was stable at 20-55°C and pH 5-9, but decreased slightly with increasing concentration of NaCl in the reaction mixture. The ARF was the most active MetPNA and preferentially hydrolyzed Glu, Leu and AlaPNA. The bitterness tryptic casein hydrolysates (BTCHs) were treated with ARF, and the bitterness of ARF-BTCHs significantly decreased with increasing amounts of released amino acids Ala, Val, Met, Ile and Leu, which show strong correlations with bitterness. Therefore, the ARF of T. pacificus HPE obtained by ultrafiltration may have a considerable potential for application in protein hydrolysis and appears to be ideally suited to the purpose of lowing bitterness in protein hydrolysates.

폐경후 여성에서 2개월간의 호르몬대치요법이 혈청 지질과 Apolipoprotein(a)의 농도에 미치는 영향

민용기 ( Min Yong Gi ),장학철 ( Jang Hag Cheol ),이관우 ( Lee Gwan U ),한인권 ( Han In Gwon ),김치정 ( Kim Chi Jeong ) 대한내과학회 1993 대한내과학회지 Vol.44 No.2

연구배경 : 폐경후 심혈관질환이 증가하며, 에스트로겐을 투여하면 이으 발생이 현저히 감소한다. Apolipoprotein(a)[apo(a)]는 lipoprotein(a)[Lp(a)]를 이루고 있는 당단백질이며 Lp(a)는 죽상경화증의 독립적인 위험인자라는 것이 밝혀져 있다. 폐경기 여성의 혈청apo(a)의 농도를 감소시키기 위한 많은 연구들이 있었으나, 호르몬 대치요법이 폐경기 여성의 혈청apo(a)의 농도에 미치는 영향은 잘 알려져 있지 않다. 이에 저자들은 폐경후 여성에서 2개월간의 에스트로겐 투여에 의한 혈청 지질 및 apo(a)농도의 변화와 이러한 변화에 프로게스토겐 병합요법이 어떠한 영향을 미치는가를 살펴보고자 전향적 연구를 시행하였다. 방법 : 혈청 FSH 농도가 40mIU/ml 이상이거나, 마지막 월경후 12개월 이상이 경과된 여성 272명을 대상으로 하였다. 자궁적출술을 시행하지 않은 여성은 무작위로 group A와 group B의 2군으로 나누어 group A는 25일 간 conjugated equine estrogen (CEE) 0.625mg과 후반 10일간 medroxyprogesterone acetate(MPA) 10mg을 병합 투여하였다. Group B는 25일간 CEE 0.625mg과 후반 10일간 MPA 5mg을 병합 투여하였다. 자궁적출술을 시행한 group C는 CEE 0.625mg 만을 25일간 경구 투여하였다. 각 group에서 이후 5일간은 투약을 중지하였으며 이를 매월 반복하였다. 혈청 콜레스테롤, 중성지방, 저밀도지단백질 콜레스테롤, 초저밀도지단백질 콜레스테롤, 고밀도지단백질 콜레스테롤, apo(a)의 농도를 측정하여 치료전후를 비교하였다. 결과 : 혈청 총콜레스테롤의 농도는 치료전 group A, B, C에서 각각 5.42±0.09mmol/L, 5.59±0.09mmol/L, 5.53±0.13mmol/L 이었고 2개월간의 호르몬대치요법후 group A, B에서 각각 4.93±0.08mmol/L, 5.22±0.08mmol/L로 통계적으로 유의하게 감소하였다(p=0.001). 혈청 저밀도지단백질 콜레스테롤의 농도는 치료전 group A, B, C에서 각각 3.29±0.07mmol/L, 3.41±0.07mmol/L, 3.40±0.10mmol/L 이었고 치료후 group A, B. C에서 각각 3.00±0.06mmol/L(p=0.0001), 3.14±0.06mmol/L, (p=0.0001) 3.18±0.12mmol/L(p=0.05)로 통계적으로 유의하게 감소하였다. 혈청 고밀도지단백질 콜레스테롤의 농도는 치료전 group A, B, C에서 각각 1.72±0.04mmol/L, 1.75±0.04mmol/L, 1.69±0.06mmol/L 이었고 치료후 group C에서만 1.90±0.07mmol/L로 통계적으로 유의하게 증가하였다(p=0.0001). 혈청 중성 지방의 농도는 치료전 group A, B, C에서 각각 1.45±0.08mmol/L, 1.54±0.08mmol/L, 1.68±0.15mmol/L 이었고 치료후 group A, B, C에서 모두 통계적으로 유의한 변화는 없었다. 혈청 초저밀도지단백질 콜레스테롤의 농도는 group A, B, C에서 각각 치료전 0.39±0.03mmol/L, 0.40±0.03mmol/L, 0.45±0.05mmol/L 이었고 치료후 group A, B에서 각각 0.30±0.02mmol/L(p=0.0001), 0.34±0.03mmol/L(p<0.05)로 통계적으로 유의하게 감소하였다. 혈청 apo(a) 농도는 group A, B, C에서 각각 치료전 357.5±33.2U/L, 348.7±28.22U/L, 376.8±54.2U/L 이었고 치료후 group A, B, C에서 각각 264.7±26.1U/L, 291.0±31.8U/L, 228±47.4U/L로 모든 group에서 통게적으로 유의하게 감소하였다(p=0.0001). 결론 : 폐경후 여성에게 호르몬 대치법을 시행하는 것은 혈청 지질과 apo(a)에 유익한 효과를 보이고 있으며, 따라서 심혈관질환 예방의 중요성을 감안할 때 폐경후 여성에게 호르몬대치요법을 시행하는 것이 바람직한 것으로 사료된다. Background : Postmenopausal women have a high risk of cardiovascular disease than premenopausal women and hormone replacement therapy [HRT] reduces the risk of cardiovascular disease. Apolipoprotein(a)[apo(a)] is attached by disulfide linkage to apo B-100 of LDL, forming lipoprotein(a)[Lp(a)]. The level of this lipoprotein is an independent risk factor for atherosclerosis. The serum level of apo(a) is stable and not affected by most dietary interventions and lipid lowering agents. There was little information available about the effect of HRT on levels of Lp(a). This study was conducted to assess the effect of HRT on serum lipids and apo(a) levels in postmenopausal women. Methods : Postmenopausal women with serum FSH level above 40mIU/ml or no menstruation for more than I year were included in the study. They received the combination of conjugnated equine estrogen (CEE) 0.625mg a day for 25 days plus medroxyprogesterone acetate 10mg(group A)or 5mg (group B) a day for the last 10 days followed by 5 days off. Hysterectomized women received CEE 0.625mg a day for 25 days (group C). HRT was repeated for 2 months. The baseline levels of serum total cholesterol, triglyceride, LDL cholesterol, VLDL cholesterol, HDL cholesterol, and apo(a) were compared with posttreatment levels. Results : Serum total cholesterol levels before treatment were 5.42±0.09mmol/L, 5.59±0.09mmol/L, 5.53±0.13mmol/L in group A, B, C respectively. After HRT they were significantly reduced to 4.93±0.08mmo/L, 5.22±0.08mmol/L in group A, B respectively (p=0.0001). Serum LDL cholesterol levels before treatment were 3.29±0.07mmol/L, 3.41±0.07mmol/L, 3.40±0.10mmol/L in gruop A, B, C respectively. After HRT they were significantly reduced to 3.00±0.06mmol/L (p=0.0001). 3.14±0.06mmol/L(p=0.0001), 3.18±0.13mmol/L(p=0.05) in gruop A, B, C respectively. Serum HDL cholesterol levels before treatment were 1.72±0.04mmol/L, 1.75±0.04mmol/L, 1.69±0.06mmol/L in gruop A, B, C respectively. After HRT they were significantly increased to 1.90±0.07mmol/L in gruop C (p=0.0001). Serum triglyceride levels before treatment were 1.45±0.08mmol/L, 1.54±0.08mmol/L, 1.68±0.15mmol/L in gruop A, B, C respectively. After HRT they were not significantly changed. Serum VLDL cholesterol levels before treatment were 0.39±0.03mmol/L, 0.40±0.03mmol/L, 0.45±0.05mmol/L in gruop A, B, C respectively. After HRT they were significantly reduced to 0.30±0.02mmol/L(p=0.0001), 0.34±0.03mmol/L (p<0.05) in gruop A, B respectively. Serum apo(a) levels before treatment were 357.5±33.2U/L, 348.7±28.2U/L, 376.8±54.2U/L in group A, B, C repectively. After HRT they were significantly reduced to 264.7±26.1U/L, 291.0±31.8U/L, 228.8±47.4U/L in group A, B, C reapectively (p=0.0001) Conclusion : These results suggest that HRT for 2 months in postmenopausal women has beneficial effect on serm lipids and apo(a) levels and HRT in postmenopausal women can improve their cardiovascular risk.

Absorption Rate of Organic Matter of Fecal Solids of Recirculating Aquaculture System Using the Sea Cucumber

U-Cheol Jeong,Feng Jin,Ga-Hyun Kang,Jong-Kuk Choi,Byong-dae Choi,Seok-joong Kang 한국수산과학회 양식분과 2014 한국수산과학회 양식분과 학술대회 Vol.2014 No.7

Physio-Chemical Characteristics of Fecal Solids of Recirculating Aquaculture System for Renewal Feed Resource for Sea Cucumber

U-Cheol Jeong,Feng Jin,Ga-Hyun Kang,Jong-Kuk Choi,Byong-dae Choi,Seok-joong Kang 한국수산과학회 양식분과 2014 한국수산과학회 양식분과 학술대회 Vol.2014 No.7

Growth of Sea Cucumber Fed Biofloc Made from Fecal Solid of RAS

U-Cheol Jeong,Feng Jin,Ga-Hyun Kang,Jong-Kuk Choi,Byong-dae Choi,Seok-joong Kang 한국수산과학회 양식분과 2014 한국수산과학회 양식분과 학술대회 Vol.2014 No.7

EFFECT OF CULTURE CONDITIONS ON CHARACTERISTICS OF GROWTH AND PRODUCTION OF FATTY ACID BY Euglena gracilis

U-Cheol Jeong,Jong-Kuk Choi,Byeong-Dae Choi,Chang-Min Kang,Seok-Joong Kang 한국수산과학회 양식분과 2015 한국수산과학회 양식분과 학술대회 Vol.2015 No.5

배양방법에 따른 Euglena gracilis의 성장 및 지방산 조성

정우철 ( U Cheol Jeong ),최종국 ( Jong Kuk Choi ),강창민 ( Chang Min Kang ),최병대 ( Byeong Dae Choi ),강석중 ( Seok Joong Kang ) 한국수산과학회 2016 한국수산과학회지 Vol.49 No.1

The quality and quantity of live food sources strongly influence the success of fish production in farming operations. Thus, critical studies of live forage species are a crucial element for progress in fish aquaculture. The fat content of food is an especially important determinant of growth in marine fish. Omega-3 highly unsaturated fatty acids (HUFA) are essential components of diet that determine the nutritional value of larval fish. Euglena is a protist that has potential as a forage species. These single-celled organisms have plant and animal characteristics they are motile, elliptical in shape and 15.500 μm in diameter. Their nutritional content is excellent, but most studies have focused on cells raised in autotrophic culture. We therefore examined differences in the lipid and fatty acid contents, and the growth of Euglena cells grown under autotrophic, heterotrophic, and mixotrophic conditions. Biomass production reached 15.03 g/L, 12.28 g/L, and 3.66 g/L under mixotrophy, heterotrophy, and autotrophy, respectively. The proportional n-3 HUFA content differed among culture methods: 10.04%, 5.80% and 10.01% in mixotrophic, heterotrophic and autotrophic cultures, respectively. Mixotrophy was to be the best form of cultivation for improving the growth and nutritional content of Euglena.

배양조건에 따른 Schizochytrium mangrovei 의 성장 및 Docosahexaenoic acid의 생산특성

중우철 ( U Cheol Jeong ),최병대 ( Byeong Dae Choi ),강석중 ( Seok Joong Kang ) 한국수산과학회 2014 한국수산과학회지 Vol.47 No.2

Both docosahexaenoic acid (DHA, 22:6n-3) and eicosapentaenoic acid (EPA, 20:5n-3) have attracted increasing attention since the first epidemiological report on the importance of n-3 essential fatty acids. Lipids in microbial cells play various biological roles and, consequently, much research has been carried out on their role in cell physiology. The lipid composition of microorganisms can exhibit considerable variations depending on environment. The effects of culture conditions, temperature (15, 20, 24, 28, 32 and 36℃), salinity (10, 20, 30, 40 and 50 psu), pH (pH5, 6, 7, 8 and 9), rotation speeds (50, 100, 150 and 200 rpm), carbon sources, nitrogen sources and C/N ratio on the production of docosahexaenoic acid, fatty-acid profiles, and acids secreted to the broth culture by the oleaginous microorganism, Schizochytrium mangrovei (KCTC 11117BP), were studied. Temperature (initially 28℃), salinity (20 psu), pH (pH7), rotation speeds (100 rpm), organism fatty acids, and secreted acids in the broth were varied during cultivation of S. mangrovei. At pH 7.0, S. mangrovei was able to accumulate lipids up to 40% of its biomass, with 13% (w/w) DHA content. The monosaccharides glucose and fructose, and yeast extract were suitable carbon and nitrogen sources, respectively. The primary omega-3 polyunsaturated fatty acid produced was docosahexaenoic acid.

돌돔(Oplegnathus fasciatus) 사료의 어분대체원으로서 DHA가 다량 함유된 발효대두박의 효과

정우철 ( U Cheol Jeong ),김봉 ( Feng Jin ),한종철 ( Jong Cheol Han ),최병대 ( Byeong Dae Choi ),강석중 ( Seok Joong Kang ) 한국수산과학회 2014 한국수산과학회지 Vol.47 No.4

This study determined the level of fermented soybean meal (FSM) that could be substituted for fish meal in the diet for parrot fish Oplegnathus fasciatus. Fish meal (FM) was used the sole protein source in the control diet. FSM was substituted for 20, 40, 60, 80, and 100% of the fish meal in the experimental diets. The FSM resulted in increased crude protein, crude fat, and crude ash, but decreased crude fiber. The methionine and tryptophan contents in the FSM increased, while lysine and threonine decreased. The 18:2n-6 fatty acid content decreased from 55.30% to 28.67%. Fermentation increased 20:5n-3 (EPA) and 22:6n-3 (DHA) by 2.03% and 15.54%, respectively, although the differ-ences were not significant. Based on growth performance, we concluded that FSM could replace up to 60% of FM for the maximum growth of juvenile parrot fish.

Mixotrophic 배양조건에 따른 Euglena gracilis의 성장과 지질에 미치는 영향

정우철 ( U Cheol Jeong ),최종국 ( Jong Kuk Choi ),강창민 ( Chang Min Kang ),최병대 ( Byeong Dae Choi ),강석중 ( Seok Joong Kang ) 한국수산과학회 2016 한국수산과학회지 Vol.49 No.1

Microalgae are functional foods because they contain special anti-aging inhibitors and other functional components, such as ecosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and omega-3 polyunsaturated fatty acids. Many of these functional dietary components are absent in animals and terrestrial plants. Thus, microalgae are widely utilized in human functional foods and in the feed provided to farmed fish and terrestrial livestock. Many marine organisms consume microalgae, often because they are in an appropriate portion of the cell size spectrum, but also because of their nutritional content. The nutritional requirements of marine organisms differ from those of terrestrial animals. After hatching, marine animals need small live forage species that have high omega-3 polyunsaturated fatty acid contents, including EPA and DHA. Euglena cells have both plant and animal characteristics; they are motile, elliptical in shape, 15-500 μm in diameter, and have a valuable nutritional content. Mixotrophic cell cultivation provided the best growth rates and nutritional content. Diverse carbon (fructose, lactose, glucose, maltose and sucrose) and nitrogen (tryptone, peptone, yeast extract, urea and sodium glutamate) supported the growth of microalgae with high lipid contents. We found that the best carbon and nitrogen sources for the production of high quality Euglena cells were glucose (10 g L.1) and sodium glutamate (1.0 g L.1), respectively.