• 한국식품과학회지
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• 제25권5호
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• pp.430-437
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• 1993

본 연구는 품질이 우수한 미린을 생산하기 위하여 효소활성이 놀은 Aspergillus oryzae와 Aspergillus Shirousamii간의 융합주인 F-50으로 미린을 제조하였다. 융합주인 F-50과 이를 비교하기 위하여 이의 친주인 A. oryzae 9-12와 A. Shirousamii IFO 6082-60으로 재래식과 효소를 첨가한 개량식으로 미림을 제조하여 생성총당과 환원당을 조사한 결과, 개량식의 경우 F-50에서 각각 42.0%, 38%로 가장 높았고, 수율도 0.85g/mash g이었다. 미림 중에 들어있는 유리 아미노산은 재래식보다 효소첨가에 의한 개량식으로 만든 제품이 월등히 높았고, 그중 glutamic acid가 387.2 mg%, arginine이 283.8 mg%, leucine이 244.0 mg%, aspartic acid가 218.0 mg%, alanine이 213.1 mg%, serine이 168.3 mg% 및 phenylalanine이 148.6 mg%로 많이 들어 있으며, 전체 아미노산의 67.5 mg%를 차지하였다. 유기산의 함량은 oxalic acid, citric acid, malic acid, succinic acid, lactic acid, acetic acid 및 propionic acid가 들어 있으며, F-50에 의하여 개량식으로 만든 미림이 38.0%로 제일 낮았다. 당의 함량은 glucose, maltose, isomaltose, maltotriose, ribose, isomaltotriose 및 isomaltotetraose가 들어 있으며 glucose의 함량이 높았다. 미림은 저장 중 포도당에 의하여 백탁이 생성되는데, 개량식의 경우 ACPase의 활성이 높은 F-50으로 만든 미림은 alcohol clouding이 0.030, water clouding이 0.018 그리고 heat clouding이 음성으로 나타나 품질이 우수하였다.

• 한국식품과학회지
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• 제22권7호
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• pp.724-731
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• 1990

안동지방의 전통적인 식혜의 제법을 조사하고 10종의 시료를 채취하여 성분분석 및 관능시험으로 품질을 평가하였다. 점차 사라져가는 전통 안동식혜의 전통적인 제법을 계승, 보존하고 그 품질향상을 도모하고 상품화할 목적으로 관능시험의 결과 식혜 담그는 재료의 비와 그 제법공정을 확립하였다. 전통 안통식혜를 관능시험으로 가장 이상적인 식혜 제조시 재료의 비는 찹쌀 : 엿기름 : 무우 : 물 : 생강 : 고추가루의 중량비는 각각 80 : 50 : 100 : 500 : 8 : 4이었다. 전통 안통식혜의 성분 중 아미노태질소 함량은 낮았으며 수용성 아미노산과 염용해성 단백질의 아미노산 조성은 다같이 glycine, glutamic acid 및 aspartic acid의 함량이 많았다. 식혜의 당 조성은 총당 및 환원당의 함량은 대체로 높았으며 유리당의 함량은 maltose가 78%로써 가장 많았고 glucose, maltotriose순이었다. 산성 protease의 활성은 1.15 unit/ml였으며 전분당 화력은 $12.5D^{40}_{30}^{\circ}$로써 식혜의 감미를 크게 증가시켰다. 관능시험 결과 선정된 우량 식혜는 매운맛과 단맛 및 산미가 잘 조화된 전통식품으로 향기는 약간의 감주향에다 매운향이 잘 조화된 향취를 나타내었고 색은 약간 붉은색을 띠었다.

• Biotechnology and Bioprocess Engineering:BBE
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• 제8권2호
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• pp.106-111
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• 2003

A novel carbohydrolase, which is a DXAMase, containing both dextranase and amylase equivalent activities, was purified from Lipomyces starkeyi KSM22. The purified DXAMase was also found to hydrolyze cellobiose, gentiobiose, trehalose and melezitose, while disproportionation reactions were exhibited with various di- and tri-saccharides, such as maltose, isomaltose, gentiobiose, kojibiose, sophorose, panose, maltotriose, and isomaltotriose with various kinds of oligosaccharides produced as acceptor reaction products. Furthermore, the purified DXAMase hydrolyzed raw waxy rice Starch and produced maltodextrin to the extent of 50% as a glucose equivalent.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 춘계학술발표대회
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• pp.251-254
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• 2000

Effect of carbon sources including agro-industrial byproduct on cell growth and production of curdlan by Agrobacterium sp. ATCC 31749 was investigated. Maximal production of curdlan was obtained when the carbon source was sucrose. The conversion rate of curdlan from 2% (w/v) sucrose was 59%. Glucose, mannose and maltose were also found to be good carbon sources for production of curdlan. Production of curdlan increased up to 3% (w/v) glucose as the carbon source and then decrease as the concentration of glucose increased. The major components of agro-industrial byproduct (AIB) were glucose, maltose, and maltose, and maltotriose. Agrobacterium sp.ATCC 31749 utilized up to 25% (v/v) AIB and produced curdlan with 29.8g/1.

• Journal of Microbiology and Biotechnology
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• 제18권9호
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• pp.1544-1549
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• 2008

MhMTS and MhMTH are trehalose ($\alpha$-D-glucopyranosyl-[1,1]-$\alpha$-D-glucopyranose) biosynthesis genes of the thermophilic microorganism Metallosphaera hakonensis, and encode a maltooligosyltrehalose synthase (MhMTS) and a maltooligosyltrehalose trehalohydrolase (MhMTH), respectively. In this study, the two genes were fused in-frame in a recombinant DNA, and expressed in Escherichia coli to produce a bifunctional fusion enzyme, MhMTSH. Similar to the two-step reactions with MhMTS and MhMTH, the fusion enzyme catalyzed the sequential reactions on maltopentaose, maltotriosyltrehalose formation, and following hydrolysis, producing trehalose and maltotriose. Optimum conditions for the fusion enzyme-catalyzed trehalose synthesis were around $70^{\circ}C$ and pH 5.0-6.0. The MhMTSH fusion enzyme exhibited a high degree of thermostability, retaining 80% of the activity when pre-incubated at $70^{\circ}C$ for 48 h. The stability was gradually abolished by incubating the fusion enzyme at above $80^{\circ}C$. The MhMTSH fusion enzyme was active on various sizes of maltooligosaccharides, extending its substrate specificity to soluble starch, the most abundant natural source of trehalose production.

• 한국미생물·생명공학회지
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• 제25권2호
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• pp.109-114
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• 1997

The Oomycete Saprolegnia ferax produces an extracellular $\beta$-amylase, Maximum enzyme yield was attained after 7 days of growth in YNB starch medium (pH 6.5) at 25$\circ$C. The amylase was pu- rified 24-fold by ultrafitration, HPLC DEAE column and HPLC gel filtration. The purfied enzyme was a monomeric glycoprotein with a molecular weight of about 44,000 dalton. The pH and temperature optima were 6.5 and 50$\circ$C, respectively. The enzyme was fairly stable up to 50$\circ$C and at acidic pH region (pH 4.0-7.0). The apparent Km and Vmax values of the enzyme against soluble starch were 0.77 mg/ml and 2,174 $\mu$moles/mg protein, respectively. Amino acid analysis indicated that the enzyme was enriched in alanine, glycine, leucine and acidic amino acid. Starch hydrolysis with the enzyme released maltose but not glucose, whereas maltotriose, Schardinger dextrin ($\alpha$-cyclodextrin) and pullulan were not hydrolysed by the enzyme. The enzyme was inhibited by Schardinger dextrin, p-chloromercuribenzoate(PCMB), CU$^{2+}$' and Hg$^{2+}$. Inhibition of the enzyme by PCMB could be reversed by the addition of cysteine and mercaptoethanol.

• Journal of Microbiology and Biotechnology
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• 제13권5호
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• pp.815-818
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• 2003

Maltosyl(G2)-erythritol, produced by the transglycosylation reaction of erythritol with maltotriose by Bacillus stearothermophilus maltogenic amylase, was not utilized either as a substrate for lactic acid production or for water-insoluble glucan synthesis. An inhibition assay of dextransucrase and mutansucrase showed that the dental caries suppression effect of G2-erythritol was greater than that of erythritol.

• 한국미생물·생명공학회지
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• 제22권1호
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• pp.73-79
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• 1994

The optimum cultural temperature and time for the pullulanase production by Bacillus cereus subsp. mycoides were 35$\circ $C and 48 hrs, respectively. The addition of egg albumin and casein to the basal medium increased the enzyme production. The enzyme was purified by ammonium sulfate fractionation and DEAE-cellulose column chromatography. specific activity of the purified enzyme was 82.37 U/mg protein and yield of theenzyume activity was 62.1%. The purified enzuyme showed a single band on ployacrylamide disc gel electrophoresis and its molecular weight was estimated to be 66.,000 by SDS-polyacrylamide disc gel electrophoresis. The isoelcular point for the purified enzyme was pH 5.0. The optimum temperature and pH were 50$\circ $C and pH 6.5, respectively. The purified enzyme was stable below 40$\circ $C and in the pH range of 6.5~10.0 The pullulanase activity was greatly inhited by Ag$^{+}$, Hg$^{2+}$ and EDTA, and its heat stability was increased by the addition of Ca$^{2+}$. The tydrolysis product with the enzyme on pullulan was maltotriose.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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• pp.352-355
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• 2000

Production of pullulan by Aureobasidium pullulans HP-2001 with agro-industrial byproducts was investigated. Agro-industrial byproducts from the rice processing industry for the traditional Korean food (AIB-A), apple juice production (AIB-B), and soybean sauce production (AIB-C) were used for carbon and nitrogen source for production of pullulan. Major components of AIB-A were glucose, maltose, maltotriose, and dextran. AIB-A and B were found to be good substitute to glucose as carbon source. Productivity of pullulan with AIB-A and B as carbon source was similar to that glucose. Molecular weight of pullulan produced with AIB-A and B was higher than that with glucose. Major components of AIB-B and C were carbohydrate, protein, fat and ash. AIB-C was also a good substitute to yeast extract as nitrogen source. Some of physiological conditions were examined for the large scale production of pullulan.

• 한국식품영양학회지
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• 제10권3호
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• pp.309-313
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• 1997

멥쌀식혜와 찹쌀식혜의 한계덱스트린을 알코올침전, Biogel P-2의 겔 크로마토그래피, Superose 12 겔 크로마토그래피 칼럼을 사용한 FPLC로 정제하여 1H-NMR 분석을 행하였다. 멥쌀식혜의 한계덱스트린은 $\alpha$-1,4-글루코시드 결합과 $\alpha$-1,6-글루코시드 결합의 비율이 1:4.5, 찹쌀식혜의 한계덱스트린은 1:5.9를 나타냈다. Pullulanase 소화로 멥쌀식혜 및 찹쌀식혜의 한계덱스트린은 말토오스, 말토트리오스, 말토테트라오스, 말토펜타오스, 말토헥사오스까지 나타내 이들이 서로 조합하여 한계덱스트린을 만들고 있는 것으로 분석되었다.