Cloning and Identification of Essential Residues for Thermostable β-glucosidase (BgIB) from Thermotoga maritima

홍수영,조계만,김용희,홍선주,조수정,조용운,김훈,윤한대,Hong, Su-Young,Cho, Kye-Man,Kim, Yong-Hee,Hong, Sun-Joo,Cho, Soo-Jeong,Cho, Yong-Un,Kim, Hoon,Yun, Han-Dae Korean Society of Life Science 2006 생명과학회지 Vol.16 No.7

A hyperthermophilic bacterium Thernotoga maritima produced thermostable ${\beta}-glucosidase$. The gene encoding ${\beta}-glucosidase$ from T. maritima MSB8 was cloned and expressed in Escherichia coli. The en-zyme (BgIB) hydrolyzed ${\beta}-glucosidase$ linkages between glucose and alkyl, aryl of saccharide groups such as salicin, arbutin, and $_pNPG$. The insert DNA contained ORF with 2,166 bp encodes a 721 amino acids (calculated molecular mass of 80,964 and pl of 4.93). The amino a.id sequence of BglB showed the similarity to family 3 glycosyl hydrolases. The molecular weight of the enzyme was estimated to be approximately 81kDa by MUG-nondenaturing PAGE (4-methylumbelliferyl 13-D-glucoside-nondenaturing polyacrylamide gel electophoresis) and SDS-PACE. The ${\beta}-glucosidase$ exhibited maximal activity at pH 7.0 and $80^{\circ}C$. By exchanging two possible residues (Glu-232 and Asp-242) to Ala by site-directed mutagenesis method, it was found that these were essential for enzymatic activity. 초고온성 세균인 Thermotoga maritima로부터 ${\beta}-glucosidase$ 유전자를 클로닝한 후 대장균 숙주에서 발현시켰다. 이 효소는 salicin, arbutin, $_pNPG$과 같은 탄소원의 ${\beta}$-글루코시드 결합을 가수분해하였다. 721개의 아미노산을 암호화하는 2,166 bp의 DNA 염기서열로된 유전자이였다. 다른 ${\beta}-glucosidase$ 효소들과 단백질 유사성을 비교한 결과 glycosyl hydrolase family 3에 속하였으며 MUG-nondenaturing PAGE와 SDS-PAGE에 의해 확인된 단백질의 크기는 약 81 kDa이었다. 효소활성은 pH 7.0, $80^{\circ}C$에서 가장 높은 활성을 나타냈으며 이 효소의 아미노산 서열에 있는 두 개의 아미노산 잔기 (232번 글루탐산과 242번 아스파르트산 잔기)를 알라닌으로 치환시켜 활성이 없어지는 것으로 보아 이 두 잔기가 효소활성에 중요한 역할을 하는 것으로 추정된다.

연구보문 : 자연과학; 야콘의 기능성 물질 프락토올리고당 특성과 효능

김수정 ( Su Jeong Kim ),권오근 ( Oh Keun Kwon ),홍수영 ( Su Young Hong ),남정환 ( Jung Hwan Nam ),손황배 ( Hwang Bae Sohn ),진용익 ( Yong Ik Jin ),장동칠 ( Dong Chil Chang ),조현묵 ( Hyun Mook Cho ) 한국국제농업개발학회 2013 韓國國際農業開發學會誌 Vol.25 No.3

Yacon [Samallanthus sonchifolius (Poepp. & Endl.) H. Robinson] , Peruvian ground apple, is a tuberous root crop with crisp, crunchy and sweet roots and considered as the king of oligosaccharides in Korea. Yacon`s fructooligosaccharides are non-digestible carbohydrates and composed of kestose, nystose, and fructofranosylnystose. The fructooligosaccharides have physiological prebiotic functionalities such the lactic acid bacteria of intestinal bifido bacteria growth, increasing mineral absorption, promoting formal functions, improving lipid metabolism, anti-obesity effects, and prevention of cardiovascular disease of triglyceride synthesis. The content of fructooligosaccharides in yacon was about 8.1% in fresh weight basis which was higher than those of other root crops such as garlic, budock, etc. However, during the storage period, the content of fructooligosaccharides decreased from 8.1% to 4.8% and 2.4% in 1 and 3 months after storage, respectively. Therefore improvement of storage conditions is needed to minimize the decrease of fructooligosaccharides. Considering these results and other studies on yacon`s biological functionalities, Various studies are needed to utilize the yacon as a functional food material.

한국산 구절초속 식물의 꽃 형태학적 특성에 따른 분류

김수정(Su Jeong Kim),남정환(Jung-Hwan Nam),진용익(Yong Ik Jin),홍수영(Soo Young Hong),윤영호(Young Ho Yoon),정진철(Jin-Cheol Jeong),김기선(Ki Sun Kim) 한국원예학회 2011 한국원예학회 학술발표요지 Vol.2011 No.10

통합세척시스템 활용시 포장재 종류별 세척감자의 품질 특성

김수정(Su Jeong Kim),손황배(Hwang Bae Sohn),Manjulata Mekapogu,권오근(Oh Keun Kwon),홍수영(Su Young Hong),남정환(Jung Hwan Nam),진용익(Yong Ik Jin),장동칠(Dong Chil Chang),서종택(Jong Taek Suh),정진철(Jin Cheol Jeong),김율호(Yul H 한국식품과학회 2016 한국식품과학회지 Vol.48 No.3

우리나라에서 가장 많이 유통되고 있는 감자 품종인 ‘수미’를 사용하여 세척감자의 실용화를 위한 적정 포장재를 개발하고자 본 연구를 수행하였다. 세척감자의 포장재에 따른 품질특성의 변화를 구명하기 위해 무포장(NP, positive control), 종이봉투(PB, negative control), 양파망(ON), 무공투명비닐백(TP), 유공불투명비닐백(OP) 총 5종의 포장재를 대상으로 Hunter 값, 색차값(ΔE value), 총 엽록소 및 글리코알카로이드(PGA) 함량 등 품질 특성을 평가하였다. 그 결과, Hunter a값(적색도/녹색도)은 세척감자 저장 12일째에 양파망(ON)과 무공투명비닐백(TP)에서 −a값을 나타내 녹색도로 바뀌었다. 색차값은 무포장(NP)에서 높게 나타나 다른 포장재에 비해 녹화가 심했다. 총 엽록소 함량은 저장기간에 따라 뚜렷하게 증가하는 경향을 보였으며, 무포장에서 저장 15일째 가장 큰 증가를 보였다. 세척감자의 괴경 내피 부위의 PGA 함량은 모든 처리에서 저장 15일째 5 mg/100 g 이하로 낮았으며, 외피 부위에서도 4.5-9.3 mg/100 g으로 국제연합식량농업기구(FAO) 권장기준(20 mg/100 g)보다 낮았다. 녹화와 각 품질평가 요인의 상관성을 구명하기 위해, 피어슨 상관분석을 한 결과, 엽록소 함량은 색차값(0.90786)과 높은 정의 상관관계를 보였으나, Hunter a값은 색차값(−0.86021), 엽록소 함량(−0.85196)과는 높은 부의 상관관계를 보였다. 글리코알카로이드(PGA)와 녹색도 품질평가 요인과는 상관관계가 없는 것으로 나타났다. 이러한 엽록소 함량, 색도 색차와 PGA 함량 등의 결과를 바탕으로 녹화와 소비자 선호도를 고려할 때 평가항목에서 우수한 유공불투명포장재가 세척감자 소포장재로 유망할 것으로 판단되었다. This study was performed to investigate the effect of packaging materials on quality characteristics of washed potatoes such as Hunter’s a value, chlorophyll and potato glycoalkaloids (PGA) content during their storage for 15 days. Packaging methods were evaluated into five ways: no packaging (NP, positive control), paper bag (PB, negative control), onion net (ON), transparent oriented to polypropylene without hole (TP), opaque oriented polypropylene with 4 holes (OP). Hunter’s a values of washed potatoes showed minus in NP and TP after 12 days storage, whereas all plus values were observed in those of PB, ON, and OP. Total chlorophyll content of washed potatoes was the highest in no packaging at 15 days after storage. The PGA content of washed potatoes showed low levels in flesh part (below 5 mg/100 g · FW) as well as in peel part (4.5-9.3 mg/100 mg · FW) in all packagings up to 15 days after storage.

고랭지 지역에서 재배한 녹두 품종들의 항산화 활성 및 아미노산 조성 비교

진용익 ( Yong Ik Jin ),홍수영 ( Su Young Hong ),김수정 ( Su Jeong Kim ),옥현충 ( Hyeon Chung Ok ),이예진 ( Ye Jin Lee ),남정환 ( Jeong Hwan Nam ),윤영호 ( Young Ho Yoon ),정진철 ( Jin Cheol Jeong ),이순애 ( Soon Ae Lee ) 한국환경농학회 2010 한국환경농학회지 Vol.29 No.4

Abstract: This study was performed to investigate differences of antioxidant activity, the content of free amino acids including GABA(gama-amino butyric acid) among mungbean cultivars grown in Highland area (Jinbu) and to compare those between seeds and sprouts. In DPPH (diphenyl picrydrazyl) radical scavenging activity, `Jangan` mungbean activity was more higher than that of other cultivars. The content of total phenolic compounds of mungbean ranged from 1,186 to 1,493 ㎍/g in seed and 2,321 to 2,783 ㎍/g in sprout. Among amino acids of seeds, the content of glutamic acid was highest in `Soseon` mungbean, and contents of almost amino acids increased during sprouting of seeds. The content of GABA that are known as a material having high functional effects on human body was also analyzed. When the relatively high content of GABA was observed in seeds of almost mungbean grown in highland, and their contents rapidly increased after sprouting from seeds. As a result of this experiment, it is expected that mungbean will be developed to a good alternative crop having high value as functional food materials in highland area of Korea.

우박저항성과 관련된 감자품종의 줄기 특성

진용익 ( Yong Ik Jin ),장동칠 ( Dong Chil Chang ),조지홍 ( Ji Hong Cho ),조광수 ( Kwang Soo Cho ),임주성 ( Ju Sung Im ),홍수영 ( Su Young Hong ),김수정 ( Su Jeong Kim ),손황배 ( Whang Bae Sohn ) 한국환경농학회 2014 한국환경농학회지 Vol.33 No.4

BACKGROUND: Recently, weather disasters such as hail and typhoon occur frequently. These threaten the stable cultivation of potatoes. It is very important to cultivate potatoes with stable under unexpected weather disasters. This study was performed to investigate the correlation between mophological characteristics of potato stem and its resistance to hail damage in different potato cultivars. METHODS AND RESULTS: Hail fall occurred for 8 minutes on May 31, 2012 in the field of Highland Agriculture Research Center located in Jinbu-myeon Gangwon-do. Potato crop grown in the field was affected by hail due to which the stems of potato were broken. The percentage of broken stem of potato was investigated as the level of damage by hail. To determine the difference in theratio of broken stem among the potato cultivars, physical characteristics of potato stem such as diameter and hardness were measured. To evaluate recovery phase after hail damage, ground coverage and yield were measured. The percentage of broken stem of cv. Goun and cv. Saebong were 30%, 26%, respectively, whereas it was 5% in the cv. Atlantic. Damage by hail was the lowest in cv. Atlantic. Diameter of the stem was 15 mm in cv. Atlantic, 13 mm in cv. Goun and 11 mm in cv. Saebong. The hardness of potato cultivars was measured which was 74 N in cv. Atlantic. 71 N in cv. Goun and 59 N in cv. Saebong. The ground coverage in cv. Atlantic was 79%, which was the highest followed by 73% in cv. Saebong and 56% in cv. Goun. The yield of cv. Atlantic was monitored at 90 days after planting which was 40 MT/ha and that of cv. Saebong was 36 MT/ha, whereas in cv. Goun, it was 30 MT/ha which was the lowest. CONCLUSION: The ratio of broken stem in cv. Atlantic was the lowest compared to cultivars. In the physical characteristics of stem, cv. Atlantic was the highest in value of diameter and hardness. Based on these results, it wasconsidered that cv. Atlantic was resistant to hail damage compared to other cultivars.

랫드를 이용한 여주 추출물의 안전성 평가

류현열(Hyeon Yeol Ryu),이소민(Somin Lee),안규섭(Kyu Sup Ahn),연용(Yeon Yong),김혜진(Hye Jin Kim),김성은(Seong-Eun Kim),이학성(Hak Sung Lee),홍수영(Su-Young Hong),김현규(Hyun-Kyu Kim),황인국(In Guk Hwang),송경석(Kyung Seuk Song) 한국식품영양과학회 2017 한국식품영양과학회지 Vol.46 No.4

본 연구에서는 항당뇨에 유효성이 있는 천연물질인 여주 추출물을 이용하여 여주에 포함된 독성물질인 vicine의 분석과 경구투여에 따른 독성을 조사하기 위하여 단회 경구투여 독성시험과 13주 반복 경구투여 독성시험을 진행하였다. 본 시료는 여주 미숙과 열매추출물로 vicine의 분석 결과 존재하지 않거나 극미량일 것으로 판단된다. 단회 경구투여 독성시험과 시험물질에 의한 이상증상과 사망동물은 발생하지 않아 여주 추출물의 ALD는 암수 모두 5,000 mg/kg/d 이상으로 판단된다. 13주 반복 경구투여 독성시험의 투여용량을 결정하기 위하여 0, 1,250, 2,500 및 5,000 mg/kg/d의 투여용량으로 2주 반복투여 용량결정시험을 실시한 결과, 모든 시험군에서 시험물질에 의한 이상증상 및 독성 변화가 관찰되지 않아 동일한 용량으로 13주 반복 경구투여 독성시험을 진행하였다. 실험기간 동안 사망률, 일반증상, 체중 변화, 사료섭취량, 안검사, 요검사, 혈액학적 검사, 혈액응고시간 검사, 혈액생화학적 검사, 부검소견, 장기중량 및 조직병리학적 소견을 관찰한 결과, 시험물질에 의한 전신적인 독성학적 변화는 관찰되지 않았다. 따라서 여주 추출물의 NOAEL은 5,000 mg/kg/d로 판단되었고, 표적장기는 관찰되지 않았다. 본 연구의 결과로 볼 때 여주 추출물은 투여 가능한 최대 용량에서도 독성이 나타나지 않는 안전한 천연물로 확인하였고, 본 시험 결과를 바탕으로 ADI는 3,000 mg/man으로 판단된다. 따라서 기능성 식품으로서의 개발 가능성을 확인하였다. This study was performed to evaluate repeated dose oral toxicity upon administration of the test substance 1,2-benzisothiazolin-3-one for 90 days and to determine NOAEL (no observed adverse effect level) and target organs in Sprague-Dawley rats. Single, 2-week repeated, and 13-week repeated oral dose toxicity studies were conducted in Sprague-Dawley rats. The dose levels of groups were 1,250, 2,500, and 5,000 mg/kg/d. All dose groups were compared with the vehicle control group. The animals were observed for clinical signs and weekly body weight. Urinalysis, hematology, and serum biochemistry analyses were conducted. Subsequently, animals were sacrificed and subjected to histopathological examination. For the result, NOAEL of ethanol extract from unripe fruit of bitter melon had an optimal dose of 5,000 mg/kg/d and acceptable daily intake up to 3,000 mg/man. There was no target organ detected. Therefore, bitter melon, which contains a variety of bioactive substances, could be widely used as a health functional food ingredient.

감자 주요 품종의 괴경 부위, 저장기간별 글리코알칼로이드(glycoalkaloid) 함량

김율호(Yul-Ho Kim),김금희(Guem Hee Kim),지혜림(Hye Rim Ji),이유영(Yu-Young Lee),박향미(Hyang-Mi Park),권오근(Oh-Keun Kwon),김수정(Su Jeong Kim),손황배(Whang-Bae Sohn),진용익(Yong-Ik Jin),홍수영(Su-Young Hong),남정환(Jeong-Hwan Nam),권 한국육종학회 2014 한국육종학회지 Vol.46 No.3

Potato glycoalkaloids (PGAs) are potentially toxic to humans at high levels, and current safety regulations have recommended that PGAs content in tubers of potato cultivars should not exceed 20 mg/100gFW. Accordingly, it is important to determine the PGAs composition and level on potato cultivars for food safety and the breeding for new cultivars with low levels of PGAs. The main aim of this study was to evaluate α-chaconine, α-solanine, and total PGAs content in the peel and cortex portions in four recent cultivars (‘Haryoung’, ‘Goun’, ‘Hongyoung’ and ‘Jayoung’), released by Highland Agriculture Research Center, together with ‘Superior’ and ‘Atlantic’. The total PGAs ranged from 16.5 to 47.7 mg/100gFW. The α-solanine/α-chaconine ratio was 1:3.2 (‘Jayoung’), 1:3.5 (‘Hongyoung’) and 1:2 (‘Superior’), whereas α-solanine was not detected in ‘Goun’, ‘Atlantic’ and ‘Hongyoung’ under the analytical condition of this experiment. 75-94% of total PGAs was existed in the peel part of all cultivars. We selected two cultivars (‘Atlantic’ and ‘Goun’) showing lower PGAs content in the cortex part. During storage at 4°C, total PGAs content fluctuated widely in early stage of storage and stabilized gradually over time in ‘Hongyoung’, ‘Superior’ and ‘Jayoung’. Thus, through the selection of cultivars and storage conditions, these results will provide consumers and breeders with fundamental information about the content of PGAs in Korea major cultivars.

호염성 Bacillus s p.가 생성하는 α -amylase 특성

조용운,조수정,홍수영,김홍출 진주산업대학교 2001 산업과학기술연구소보 Vol.- No.8

양질의 간장을 제조하기 위한 목적의 일환으로서 재래식 간장으로부터 α -amylase를 분비하는 미생물을 분리하기 위하여 Soluble starch를 넣어 GPY배지를 이용하여 투명환을 크게 나타내는 균주들을 분리 선정하였다. 1. 분리균 중에서 전분 분해능이 가장 우수한 것을 선정하여 각종 생리 및 생화학적 검사, BiologTM system을 통해 이 균주가 Bacillus sp.임을 확인하고 Bacillus sp.라고 명명하였다. 2. 이 균의 생육 최적 온도는 30℃이었으며 5% NaCl 첨가 배지에서 가장 생육도가 높은 호염성균이었다. 3. 균의 크기는 0.8∼1.0×2.5∼3㎛의 단간균으로서 flagella가 있다. 4. α -amylase의 활성은 균체내 효소인 경우 pH5.4, 50℃에서 최대 활성도를 나타내었으며 균체외 효소인 경우는 pH 6, 60℃에서 최대 활성을 나타내었다. 5. Starch-SDS-PAGE 방법에 의하여 α -amylase로 추정되는 3개의 활성 밴드를 확인하였는데 분자량은 각각 97KD 이상, 66KD, 55KD이었다. A bacterial strain which produced α -amylase was isolated from soy- souce, identified to B acillus sp. by physiological and biochemical analysis. For efficient selection of α -amylase producers, microorganisms which used it in the presense of soluble starch were isolated. The optimum culture condition of B acillus sp. was 30℃ and pH7. The strain grew at the medium include 2∼10% concentration of NaCl. The α -amylase activity of the extracellular and intracellular enzyme were shown the highest level at pH 6, 60℃ and pH 5.4, 50℃. The molecular weight of α -amylase was estimated to be over 97KD, 66KD and 55KD by Starch-SDS-PAGE.