• 한국식품영양학회지
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• 제6권4호
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• pp.294-300
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• 1993

This study was carried out to investigate the influences of cultural conditions of koji on the production of saccharogenic amylase during rice-koji making by Aspergillus awamori var. kawachii which is now widely used as koji-mold in brewing Tikju and Yakju in Korea. The optimum cultural temperature for the production of saccharogenic amylase by this mold was 36$^{\circ}C$, and at this temperature it needed 40 hours of cultivation for maximum production of this enzyme. It was favorable for high production of both organic acid and saccharogenic amylase to shift the cultural temperature form initial 36$^{\circ}C$ to 32$^{\circ}C$ after 20~25 hours of cultivation. The production of saccharogenic amylase was low when the water content of steamed rice was below 35%, but its production was high at 40~60% of water content. When the quantity of conidial inoculation was too small, the production of saccharogenic amylase was low in initial phase, but it was retrived after 40 hours of cultivation. When koji-thickness was over 3cm, the production of saccharogenic amylase was markedly restricted. The saccharogenic amylase of this koji was stable at pH 2~7, and showed high activity at pH 2~5.

• 미생물학회지
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• 제11권2호
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• pp.89-100
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• 1973

Dextrinogenic and saccharogenic amylase activities of Rhizopus isolated from various substrates collected throughout South Korea are measured, and their amylase activities are surveyed from taxnomical, ecological, and physiological viewpoints. Among the 151 strains of Rhizopus, strain number 49 exhibiting most prominent saccharogenic amylase activity is selected as a best strain, and strain number 17 is selected as a best strain for dextrinogenic amylase activity. Amylase activities of Rhizopus are so variable in different strains even in the same species. In general, however, R. japonicus, R. liquefaciens, and R. shanghaiensis show high saccharogenic amylase activities, and R.chiuniang, R.achlamydosporus, and R.bahrnensis show high dextrinogenic amylase activities, while R.nigricans exhibits lower activities for both amylase. The strains isolated from kneaded cereals, such as "meju" and "kockja", exhibited very strong dextrinogenic and saccharogenic amylase activities as compared with the strains isolated from other sunstrates. The mean value of dextrinogenic amylase activities of the strains from southern inland region and saccharogenic amylase activities of the strains from middle coast region are, more or less, higher than those of the strains from the other regions. In the culture at 30.deg.C, those strains which exhibit better mycelial and air mycelial growth than sporangial formation show very high dextrinogenic and saccharogenic amylase activities. amylase activities.

• 한국식품영양학회지
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• 제7권1호
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• pp.51-57
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• 1994

A nuluk, a Korean traditional koji for brewing, was made with wheat flour and Aspergillus usamii mot. shirousamii S1 which had strong abilities in producing amylase and protease. The cultural conditions for the production of saccharogenic and proteolytic enzymes were tested. The productivities of saccharogenic and dextrogenic enzymes were improved when nuluk was made with unsteamed wheat flour as compared with steamed one, but those of proteolytic enzyme and organic acid were reduced. The addition of water containing 0.5% of hydrochloric acid was unfavorable for the production of saccharogenic, dextrogenic and proteolytic enzymes. The optimum ratios of water added to wheat flour for the production of saccharogenic enzyme and proteolytic enzyme were 32% and 28%, respectively on the basis of wheat flour. The optimum temperatures for the production of saccharogenic enzyme and proteolytic enzyme were 36$^{\circ}C$ and 28$^{\circ}C$, respectively. The activity of saccharogenic enzyme reached its maximum after 120 hours of cultivation at 36$^{\circ}C$, but that of proteolytic enzyme 96 hours. The productivity of saccharogenic enzyme was enhanced when the nuluk was molded after 24 hours of precultivation but that of proteolytic enzyme was reduced as compared with no molding.

• 한국식품영양학회지
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• 제6권2호
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• pp.96-102
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• 1993

A Nuluk, a Korean traditional koji for brewing, was made with wheat flour and Rhizopus japonicus T2 which had a good aroma and strong abilities in producing saccharogenic and proteolytic enzymes, and cultural conditions for the production of those two enzymes were tested. The productivity of saccharogenic enzyme was markedly improved when Nuluk was made with unsteamed wheat flour as compared with that with steamed one, but that of acid protease was reduced. The addition of water containing 0.5% hydrochloric acid was unfavorable for the production of saccharogenic enzyme and neutral protease. The optimum ratio of water added to wheat flour for the production of saccharogenic enzyme and proteolytic enzyme was 28% on the basis of wheat flour. The productivity of saccharogenic enzyme was enhanced "when the Nuluk was molded after 10~20 hours precultivation but that of proteolytic enzyme was reduced as compared with no molding. The optimum temperature for the production of saccharogenic enzyme was 28f and that of proteolyic enzyme was also 28$^{\circ}C$. The optimum cultural time for the production of saccharogenic enzyme was 36 ~72 hours at 3$0^{\circ}C$ and that of proteolytic enzyme was 36 hours.ours.

• 한국식품영양학회지
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• 제6권2호
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• pp.89-95
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• 1993

A Nuluk, a Korean traditional Koji for brewing, was made with wheat flour and Aspergillus oryzae L2 which had a good aroma and strong abilities In producing saccharogenic and dextrogenic enzymes. The cultural conditions for the production of saccharogenic and proteolytic enzymes were tested. The productivity of dextrogenic enzyme was improved when Nuluk was made with unsteamed wheat flour as compared with steamed one, but that of proteolytic enzyme was reduced. The addition of water containing 0.5% hydrochloric acid was unfavorable for the production of those two enzymes. The optimum ratio of water added to wheat flour for the production of those two enzymes was 28$^{\circ}C$ on the basis of wheat flour, The productivity of saccharogenic enzyme was enhanced when the Nuluk was molded after 20 hours of precultivation, but that of proteolytic enzyme was reduced as compared with no molding. The optimum temperatures for the production of saccharogenic enzyme and proteolytic enzyme were 36$^{\circ}C$ and 28$^{\circ}C$, respectively.

• Journal of Microbiology
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• 제43권6호
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• pp.561-568
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• 2005

A newly-isolated thermophilic strain of the zygomycete fungus Rhizomucor pusillus 13.36 produced highly active dextrinogenic and saccharogenic enzymes. Cassava pulp was a good alternative substrate for amylase production. Dextrinogenic and saccharogenic amylases exhibited optimum activities at a pH of 4.0-4.5 and 5.0 respectively and at a temperature of $75^{\circ}C$. The enzymes were highly thermostable, with no detectable loss of saccharogenic or dextrinogenic activity after 1 hand 6 h at $60^{\circ}C$, respectively. The saccharogenic activity was inhibited by $Ca^{2+}$ while the dextrinogenic was indifferent to this ion. Both activities were inhibited by $Fe^{2+}\;and\;Cu^{2+}$ Hydrolysis of soluble starch by the crude enzyme yielded $66\%$ glucose, $19.5\%$ maltose, $7.7\%$ maltotriose and $6.6\%$ oligosaccharides.

• Mycobiology
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• 제39권4호
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• pp.278-282
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• 2011

The objective of this study was to find useful fungi with ${\alpha}$-amylase activity from the Korean traditional nuruk for the quality of traditional Korean alcoholic beverage. In this study, 165 samples of traditional nuruk were collected from 170 regions throughout Korea and the fungi were isolated to a total of 384 strains. In order to investigate the effect of microflora on nuruk, ${\alpha}$-amylase activity, saccharogenic power (SP), starch hydrolysis activity and acid producing activity were evaluated. Ten strains were selected by ${\alpha}$-amylase activity, which ranged from 458.47 to 1,202.75 U/g. The size of the discolored zone for the starch hydrolysis activity of each fungus ranged from 0.3 to 2 cm. The SP of the 10 strains ranged from 228.8 to 433.4 SP. Of the 10 stains, three were identified as Aspergillus oryzae, two as Aspergillus flavus, two as Lichtheimia sp., one as Rhizopus oryzae and two as other strains. The total aflatoxins present in the nuruks were examined using enzyme-linked immunosorbent assay. The 10 nuruks had less than 1.11 ppb of aflatoxins.

• Applied Biological Chemistry
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• 제13권3호
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• pp.231-235
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• 1970

1. 내열성 사상균 Humicola속의 Amylase를 정제하였다. 2. DEAE-Cellulose Column Chromatography로 2개의 활성구분으로 나누어 졌다. 3. 즉 pH 6.0, 0.05M와 0.5M의 인산염완충용액으로 용출시킬때 전자에서 당화형, 후자에서 호정화형 Amylase가 각각 분리되었다. 4. 이 당화형 Amylase의 최적 pH는 $4.5{\sim}5.5$이고, 안정 pH 범위는 $4.0{\sim}9.0$범위였다. 최적온도는 $60{\sim}65^{\circ}C$로 다른 사상균의 그것보다 훨씬높고 $80^{\circ}C$ 이상에서는 불활성화 되었다.

• 미생물학회지
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• 제3권2호
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• pp.9-14
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• 1965

The enzyme-producing potentials of industrially important strains of Aspergillus spp. were studied. Irradiation of three original isolates of Aspergillus oryzae to ultra-violet rays resulted in the production of mutants which differed from the parent riboflavin and vitamin $B_{12}$ in culture media. 1. Irradition three strains of Aspergillus oryzae to ultraviolet light produced mutants and two strains of them were selected for soy sauce brewing. 2. The two strains are the physiological mutants of Aspergillus oryzae. Both were found to have superior enzyme activity to their relatives. 3. Aspergillus oryzae UV-induced mutant 172-722 and 569-713 were more powerful than others in the production of riboflavin and vitamin $B_{12}$. The enzyme activity of these strain were high and decreased only slightly even in 20 percent solution of NaCl. 4. Aspergillus oryzae UV-induced mutant 172-722 had more powerful protease producibility in wheat bran media than in modified Czapek's solution. On the contrary, Aspergillus oryzae UV-induced mutant 569-713 had more powerful producibility of saccharogenic and dextrinogenic amylase in modified Czapek's solution than in mold bran. 5. Aspergillus oryzae UV-induced mutant 172-722 formed the spore rapidly and Aspergillus oryzae UV-induced mutant 569-713 did ordinarily. 6. It is found from the results that Aspergillus oryzae UV-induced mutant 172-722 is valuable material for the manufacture of soy sauce because of its high protease activity in 20 percent solution of NaCl. Aspergillus oryzae UV-induced mutant 569-713 is suitable for soy bean mash and for fermented red pepper sauce for its high saccharogenic and dextrinogenic amylase activity in 20 percent solution of sodium chloride.

• Applied Biological Chemistry
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• 제8권
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• pp.45-50
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• 1967

세균성(細菌性) ${\alpha}-amylase$로 전분(澱粉)을 액화(液化)시키고 곰팡이 4균주(菌株)의 당화효소제(糖化酵素劑)로서 양화(糧化)시켜 발효율(醱酵率)을 비교(比較)하여 그 이용성(利用性)을 조사(調査)하고 담금농도(濃度)에 따라 필요(必要)한 SP를 실험(實驗)하였다. 1) 제국용(製麴用)곰팡이 Aspergillus 3주(株)와 Rhizopus 1주(株)에 대(對)하여 당화력(糖化力) 내산성(耐酸性) 발효성적(醱酵成績)을 비교실험(比較實驗)한 결과(結果) Asp. usamii mut shirousamii가 양호(良好)하였다. Rhi delemar 는 효소(酵素)로서의 제성질(諸性質)은 양호(良好)하나 대량제국시(大量製麴時) 오염도(汚染度)가 컸다. 2) 담금농도(濃度)와 국사용량(麴使用量)을 각각(各各) 다르게하여 발효실험(醱酵實驗)을 한결과(結果) 담금농도(濃度)에 따른 필요(必要)한 SP가 밝혀졌다. 3) 공장규모(工場規模)에 가까운 실험(實驗)을 통(通)하여 당화효소(糖化酵素)에 필요(必要)한 SP보다 1.2% 이상(以上) 첨가(添加)하는 것이 안전(安全)하였다. 그 이유(理由)로서는 열(熱) 산(酸)에 의(依)한 효소(酵素)의 파괴율(破壞率)을 생각(生覺)해야 하기 때문이다. 4) 세균성(細菌性) ${\alpha}-amylase$로 전분(澱粉)을 액화(液化)시킨다음 당화(糖化)하였음으로 효모(酵母)의 증식조건(增殖條件)이 알맞아 발효시간(醱酵時間)이 단축되었다.