• 한국식품영양학회지
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• 제12권2호
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• pp.164-169
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• 1999

To develope the scientific preparation method of Dorean traditional rice drink 'Sikhye', effect of malt and commercial amylolytic enzymes in preparation of malt-Sikhye were studied. amylase activity of malt used in this study was 9,725unit/g. In malt-Sikhye preparation effective saccharifying conditions were 4% of malt 20% of rice at 6$0^{\circ}C$ for 5hour. Commercial amylolytic enzymes such as $\beta$-amylase(Bio-zyme ML Himaltosin GL) $\alpha$-amylase(Bokhabhyoso 5000, Teramyl and Fungamyl) and pulluanase(en-zyme CK-20) were not effective in saccharification for Sikhye preperation.

• Journal of Microbiology and Biotechnology
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• 제24권4호
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• pp.447-452
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• 2014

To isolate novel and useful microbial enzymes from uncultured gastrointestinal microorganisms, a fecal microbial metagenomic library of the pygmy loris was constructed. The library was screened for amylolytic activity, and 8 of 50,000 recombinant clones showed amylolytic activity. Subcloning and sequence analysis of a positive clone led to the identification a novel gene (amyPL) coding for ${\alpha}$-amylase. AmyPL was expressed in Escherichia coli BL21 (DE3) and the purified AmyPL was enzymatically characterized. This study is the first to report the molecular and biochemical characterization of a novel ${\alpha}$-amylase from a gastrointestinal metagenomic library.

• Archives of Pharmacal Research
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• 제13권1호
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• pp.33-37
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• 1990

The effects of pH values, temperature and some elements on the amylolytic activity and stability of the purified S. aureofacienc 77 amylase were studied in this investigation. The purified enzyme showed its maximum activity at pH 6 within 8 min incubation at $40^{\circ}C$. None of the tested 6 metals showed on stimulatory effect on the enzymatic activity, $Fe^{+++}$, $Cu^{++}$ and $Hg^{++}$ at high dose inhibited the enzyme activity to great extent as compared with $Zn^{++}$, $Mn^{++}$ and $Fe^{++}$ whih gave less effect in this respect. The enzyme liquor was found to be thermolabile, since it lost completely its activity after 4 days incubation under room temperature and showed maximum activity during this period as a result of additions of $Ca^{++}$and NaCl, Gradual reduction was however recorded until activity reached 30% after 60 days of incubation.

• 한국균학회지
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• 제30권2호
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• pp.147-151
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• 2002

Trichoderma속 균주는 느타리버섯 재배 시 발생되는 버섯 푸른곰팡이병의 주요 원인균이다. 후발효된 버섯 배지로부터 버섯 푸른곰팡이병균에 항균활성을 나타내는 길항세균(KATB 99121, KATB 99122 및 KATB 99123)을 분리하였다. 분리세균 중 KATB 99121은 T. harzianum(4균주). T. viride 및 T. hamatum과 동물병원성 곰팡이 Candida albicans에 대하여 우수한 억제 활성이 관찰되었고, 특히 세균의 배양상등액 접종실험에서 강한 항균활성을 보였다. 또한, KATB 99121은 전분, 단백질 및 섬유소를 분해하는 효소를 세포외로 분비하는 것으로 관찰되었고, KATB 99122와 KATB 99123은 전분, 단백질, 섬유소 분해효소는 물론 지질 분해효소도 분비하고 있었으며 ${\beta}$-glucosidase활성도 높은 것으로 확인되었다. 앞으로 이들 길항세균들을 이용하여 느타리버섯 푸른곰팡이병 방제를 위한 미생물 살균제의 개발에 대한 연구를 수행할 예정이다.

• 한국식품과학회지
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• 제22권3호
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• pp.296-299
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• 1990

제조방법이 간편하고 감미도가 높은 새로운 식혜 제조 방법을 개발하였다. 역가가 높은 엿기름만을 분획하여 Tea-bag$(16{\times}20cm)$에 넣어 엿기름 추출공정을 간편하게 하였으며 여기에 ${\alpha}-amylase$, glucoamylase, glucoisomerase를 첨가하여 쌀 전분의 분해를 촉진시켜 단맛이 강한 단당류로 분해되도록 하였다. 식혜의 제조는 엿기름과 효소를 넣은 Tea-bag을 물로 추출한 후 여기에 고두밥을 넣어 당화시켰다. 재래식 방법에 의하여 만든 식혜의 당 조성은 fructose 1.8%, glucose 7.5%, maltose 49.5%, DP3 8.6% 그리고 DP4 이상이 32.5%이었으나 본 연구에서 개발된 방법에 의하여 제조한 식혜는 fructose 6.7%, glucose 89.0%, maltose 1.9%, DP3 0.9% 그리고 DP4 이상이 1.6%로 나타나 쌀 전분의 대부분이 단당류로 분해가 되어 설탕 첨가없이도 감미가 높은 식혜를 제조할 수 있었다.

• 한국미생물·생명공학회지
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• 제23권6호
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• pp.737-746
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• 1995

Through the study of identification of filamentous molds isolated from 12 traditional Nuruk, collected from several regions in Korea, 78 strains of Absidia spp., including Absidia corymbifera, Absidia ramosa, and Absidia sp. of which specific names were not identified, 19 strains of Rhizopus spp. including Rhizopus cohnii, Rhizopus arrhizus, and Rhizopus oryzae, 8 strains of Circinella spp., 1 strain of Actinomucor sp., 49 strains of Aspergillus spp., including Aspergillus oryzae, Aspergillus flavus, Aspergillus flavus var. columnaris, Aspergillus wentii, Aspergillus candidus, Aspergillus fumigatus, Aspergillus niger, and Aspergillus foetidus, 2 strains of Cladospoyium spp. and 2 strains Botryotrichum spp., etc. total 159 kinds of filamentous molds were isolated and identified. There were many differences in numbers and distributions of filamentous molds from each Nuruk according to their collected region. Absidia spp. were most frequently isolated from every Nuruk sample. Aspergillus oryzae, Aspergillus candidus, and Rhizopus cohnii showed even distribution. Penicillium sp. and Mucor sp. were not detected. Actinomucor sp., Aspergillus foetidus, Botryotrichum sp., and Cladosporium spp., which have not been reported by far, were found. Amylase activities, pH stability of amylase, and acid productivity of isolated strains were compared.

• 미생물학회지
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• 제7권4호
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• pp.159-166
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• 1969

It is necessry to develop and strengthen the activity of enzymic source which in low applied for maggerley brewing as an amylolytic and proteolytic starter, recently in this country the active and strong enzymic starter is required for the better brewing and to substitute another starch material for the present wheat flour. In this study, manufacturing method the strong enzymic source have been developed and established with use of raw wheat bran plus fungal strains of Rhizopus sp. and Aspergillus usamii the culture of starter. The results on experimental the activities of enzymic sources (stater) are as following ; 1. Method of making the enzymic source (starter) is to cultivate the strains of Asperguillus orzyae, Asp. kawachii, Asp usamii and Rhizopus sp. in the acid treated raw or heatboiled wheat bran. 2. The saccharogenic pwoer (S.P.) of enzymic source which consisted of raw bran plus fungi and cultured in it is generally stronger than those of heat-boiled bran plus fungi, the strongest power was shown in the culture of Rhizopus plus raw bran, and the next other is in mixture of Asp.usamii and Rhizopus on raw wheat bran. 3. The most strong alpha amylase activity was expressed in the plot of Asp.oryzae on heat-boiled wheat bran, the next was in the culture of Rhizopus nad Aspergillus usamii on raw wheatbran. 4. The most vigourous acidic proteinase activity was expressed in the micture of raw bran plus Asp. usamii and Rhizopus those were independentlu cu;tured before mixing for neutral proteinase activity, it was shown in the mixed culture of Asp. usamii and Rhizopus on raw wheat bran, the msot active alkaline proteinase activity of enzymic source was found in the plot of raw bran material. 5. For poly-preptidase activity in pH 6.5 it is found that the culture of Rhizopus and Asp.usamii on raw bran was most active among them of enzymic sources. 6. Generally, it is concluded that culture of fungi on acid treated raw wheat bran is stronger in its activity than those of heat boiled wheat bran, especially the culture of Rhizopus nad Asp.usamii on raw bran exhibited the most vigorous and non-polarized activity for all aspects, so it is considered to be most desirable enzymic stater in Korean Maggerley brewing and this would be able to substitute brewing material for the present wheat flour because of its strong and wide hand activity of amylolytic and proteolytic action.

• 미생물학회지
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• 제23권3호
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• pp.215-222
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• 1985

Distribution pattern and activity of heterotrophec bacteria were measured in the mudflat of Nakdong river estuary. In March and June, 1985, community sizes of amylolytic, lipolytic and proteolytic bacteria as well as total viable counts were measured. Vertical distribution of bacterial community size increased a few orders of magnitude from Narch to June. Heterotrophic activity was estimated in turnover time with $U-[^{14}C]-glucose$. Turnover time reduced considerably in June compared to that of March. To sxamine correlations for measured bacterial groups, turnover time and environmental factors, correlation coefficient matrix was obtained. These measured characteristics did not consistently correlate well with one another.

• Journal of Microbiology and Biotechnology
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• 제20권11호
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• pp.1539-1545
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• 2010

In beer, glutathione works as the main antioxidant compound, which also correlates with the stability of the beer flavor. In addition, high residual sugars in beer contribute to major nonvolatile components, which are reflected in a high caloric content. Therefore, in this study, the Saccharomyces cerevisiae GSH1 gene encoding glutamylcysteine synthetase and the Saccharomycopsis fibuligera ALP1 gene encoding ${\alpha}$-amylase were coexpressed in industrial brewing yeast strain Y31 targeting the ${\alpha}$-acetolactate synthase (AHAS) gene (ILV2) and alcohol dehydrogenase gene (ADH2), resulting in the new recombinant strain TY3. The glutathione content in the fermentation broth of TY3 increased to 43.83 mg/l as compared with 33.34 mg/l in the fermentation broth of Y31. The recombinant strain showed a high ${\alpha}$-amylase activity and utilized more than 46% of the starch as the sole carbon source after 5 days. European Brewery Convention tube fermentation tests comparing the fermentation broths of TY3 and Y31 showed that the flavor stability index for TY3 was 1.3-fold higher, whereas its residual sugar concentration was 76.8% lower. Owing to the interruption of the ILV2 gene and ADH2 gene, the contents of diacetyl and acetaldehyde as off-flavor compounds were reduced by 56.93% and 31.25%, respectively, when compared with the contents in the Y31 fermentation broth. In addition, since no drug-resistant genes were introduced to the new recombinant strain, it should be more suitable for use in the beer industry, owing to its better flavor stability and other beneficial characteristics.

• 한국식품과학회지
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• 제34권2호
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• pp.269-273
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• 2002

무는 소화 효소가 많이 함유되어 있어 소화작용을 돕는 것으로 알려져 있는 채소류로 배추에 비해 amlyase 함량이 월등히 높은 채소이다. 본 연구에서는 무 김치를 제조하여 발효일수별로 전분가수분해 효소인 ${\alpha}-$, ${\beta}-amlyase$, glucoamylase와 protease의 활성을 측정한 결과 전분 가수분해 효소 중 ${\alpha}-amylase$는 김치 제조 직후 0.49 unit/mg protein으로 최대 활성을 보인 후 감소되었다가 발효 2일 이후 활성이 증가되었다. 반면, ${\beta}-amylase$, glucoamylase, protease는 모두 pH 4.1, 산도 0.44%를 보인 무 김치의 숙성적기였던 발효 2일째 각각 505.73, 13.43, 1.72 unit/mg protein으로 최대활성을 보였다. 무 김치의 발효 일수별 관능 평가에서도 역시 효소 활성이 최대를 나타내었던 발효 2일째 전반적인 기호도가 가장 높게 나왔다. 김치의 숙성 적기에는 전분 가수분해 효소와 단백질 가수분해 효소가 활발히 작용하여 탄수화물과 단백질이 가수분해되어 유리당과 아미노산을 생성하면서 김치의 맛도 상승되는 것으로 여겨진다.