• Title/Summary/Keyword: ${\alpha}$-amylase activity

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Quality Characteristics of Rice-doenjang during Fermentation by Differently Shaped Meju and Adding Starter (메주 형태와 Starter 첨가에 따른 쌀된장의 품질특성 변화)

  • Lee, Sun-Young;Park, Na-Young;Kim, Ji-Yeun;Choi, Hye-Sun
    • The Korean Journal of Food And Nutrition
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    • v.25 no.3
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    • pp.505-512
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    • 2012
  • This study evaluated the quality characteristics of rice-doenjang prepared with Aspergillus oryzae MD05 and Bacillus subtilis HJ18-4. The physicochemical characteristics of rice-doenjang prepared with three types of meju, such as grain type(Rice 1), disc shape(Rice 2), and brick shape(Rice 3), were compared. We determined amino and ammonia nitrogen contents, protease and amylase activities, reducing sugar content, and total aerobic counts and lactic acid bacteria counts. The amino nitrogen and reducing sugar contents in all meju types gradually increased during fermentation. The amino nitrogen contents reached 151.5~200.0 mg%. Rice 3 were had the highest levels among the 4 types of rice-doenjang. After 42 days of fermentation, amylase and protease activity of Rice 3 were 366.57 and 94.26 unit/g, respectively, which were the highest levels among the 4 types of rice-doenjang. The total aerobic bacteria counts were not changed during 42-day fermentation. This results suggest that high quality characteristics of brick-shaped meju(Rice 3) were better than those of the other meju preparations.

Quality Characteristics of Yakju Fermented with Wild Grape and 4 Kinds of Cereals (곡물을 달리하여 제조한 머루(Vitis coignetiae) 약주의 품질특성에 관한 연구)

  • Seo, Jung-Soon;Lee, Jae-Sung;Byun, Gwang-In;Kwak, Eun-Jung
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.37 no.11
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    • pp.1472-1478
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    • 2008
  • Four kinds of wild grape Yakju were fermented with wild grape and cereal such as rice, glutinous rice, barley or millet, and their quality characteristics were investigated. Reducing sugar, total sugar, and activities of $\alpha$- and $\beta$-amylase decreased until 2nd day, increased on 3rd day, and gradually decreased after 5 days of fermentation. Reducing sugar content was in the order of glutinous rice> barley> rice> millet group, and this was consistent with the result of $\beta$-amylase activity. Total sugar content was in the order of glutinous rice> rice> barley> millet group, and it was consistent with starch content of each cereal. Alcohol content decreased after 2 days, then glutinous rice group gradually increased from 3 days whereas other groups showed no difference from 5 days of fermentation. pH decreased until 2 days of fermentation, slightly increased and then showed almost no change after 5 days of fermentation. Total acid increased until 2 days, then decreased on 3rd day of fermentation, and gradually increased in the order of barley> millet> rice> glutinous rice group. L value was the highest in the initial day of fermentation, however it decreased with fermentation time. While a value was also the highest in the initial day of fermentation, it gradually decreased after slightly increasing in 3 days of fermentation. In contrast, b value was the lowest in the initial day of fermentation. It greatly increased until 3 days, then decreased on 5th day of fermentation and gradually increased again. Groups of rice and glutinous rice had more brown color than those of barley and millet. In the sensory evaluation, wild grape Yakju using rice was the most preferred in taste, flavor, and overall preference.

Fermentation Characteristics of Low Salted Kochujang Prepared with Sub-materials (부원료를 첨가한 저식염 고추장의 발효특성 변화)

  • Kim, Dong-Han;Yang, Sung-Eun
    • Korean Journal of Food Science and Technology
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    • v.36 no.1
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    • pp.97-104
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    • 2004
  • Effects of sub-materials such as, ethanol, mustard, and chitosan, on enzymatic, microbial and physicochemical characteristics of kochujang were investigated during fermentation. Activity of ${\alpha}$-amylase was low in chitosan-added kochujang, whereas those of ${\beta}$-amylase and pretense did not show any remarkable difference. Viable cells of yeast and bacteria decreased in sub-material-added kochujang during fermentation, with yeast counts decreasing more rapidly in ethanol- and mustard-added kochujang than that with chitosan. Consistency of kochujang decreased during fermentation, with the highest consistency observed in ethanol-added kochujang. Oxidation-reduction potential was low in chitosan-added kochujang. Water activity of all kochujang groups decreased during fermentation with the lowest in ethanol-added kochujang. Hunter L-, a-, and b-values of chitosan-added kochujang were higher than other groups, whereas increase in total color difference of low-salt without sub-material group was lowest pH of kochujang was the highest in ethanol-added kochujang, whereas titratable acidity increased remarkably in chitosan-added group. Total sugar and reducing sugar contents of kochujang were high in ethanol-and mustard-added groups, whereas ethanol production decreased remarkably in mustard-added kochujang. Amino nitrogen content was highest in low-salt without sub-material kochujang during late aging period. Ammonia nitrogen content was lower in mustard-added kochujang. After 12 weeks of fermentation, ethanol-added kochujang was more acceptable than mustard-and chitosan-added groups in taste, color, and overall acceptabilities.

Studies on improvement of manufacturing method of enzymic source for Maggerley(Korea wine) brewing(I) (막걸리의 제조를 위한 효소제의 개발연구 1)

  • 이성범;최경환;임동순;김덕치
    • Korean Journal of Microbiology
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    • v.7 no.4
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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.

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Physiological Activities and Inhibitory Effect of Extracts of Cynanchi wilfordii Radix and Perilla sikokiana against Cell Differentiation in 3T3-L1 Adipocytes (백하수오와 자소엽 추출물의 생리활성 및 3T3-L1 전지방세포에 대한 분화 억제 효과)

  • Kim, Seon Jeong;Kang, Seung Mi;Ko, Keon Hee;Nam, Sanghae
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.45 no.5
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    • pp.642-650
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    • 2016
  • Cynanchi wilfordii Radix (CW) and Perilla sikokiana (PS) were extracted under different conditions to study their antioxidant, anti-diabetic, and anti-obesity activities. Their potentials as functional food ingredients were investigated. The highest total phenol contents were $15.74{\pm}0.69mg/g$ for CW100 [100% fermented ethanol (FE) extract from CW] and $39.37{\pm}3.46mg/g$ for PS50 (50% FE extract from PS). When extracts were processed at 1 mg/mL, DPPH radical scavenging activities were $79.79{\pm}0.79%$ and $82.69{\pm}1.07%$, respectively, at CW100 and PS50. ABTS radical scavenging activities were $80.20{\pm}2.86%$ and $75.00{\pm}1.78%$, respectively, at CW100 and PS50. However, ferric reducing antioxidant power activities at 1 mg/mL were higher than 80% for PS under all extraction conditions. The highest ${\alpha}$-amylase inhibitory activities were $51.56{\pm}0.56{\sim}59.2{\pm}1.13%$ at CW50 and $46.70{\pm}0.32{\sim}66.17{\pm}0.55%$ at PS0. Cell differentiation inhibitory effects in 3T3-L1 adipocytes were $29.49{\pm}2.98%$ at CW100 and $23.31{\pm}0.61%$ at PS50. The inhibitory effect of the CW100-PS50 mixture was $43.03{\pm}1.63%$, which was significantly higher than those of individual extracts.

Biosynthesis of the extracellular enzymes in de novo during the differentiation of Aspergillus niger (검정곰팡이의 형태분화에 따른 세포외성효소의 신생적생합성에 관한 연구)

  • Kim, Jong-Hyup
    • The Korean Journal of Mycology
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    • v.6 no.2
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    • pp.1-10
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    • 1978
  • In de novo biosynthesis of the extracellulor enzymes-proteinsaes, alpha and gluc-amylases during the synchronized differentiation of Aspergillus niger in submerged culture and surface liquid culture were investigated. Gluc-amylase was synthesized in the stage of presporulation in which phialide formation is involved. Proteinase was synthesized both in the stages of conidiophore formation and presporulation. Alpha-amylase was synthesized during presporulation and sporulation stages, the activity of enzyme lasted for seven days on surface liquid culture. It seemed that the synthesis was occured in de novo partly repressed by the catabolite, and its nature was found to be constitutive since it is produced in non-starch medium. Polyacrylamide gel electrophoresis have shown that presporulating and sporulating body produced diverse types of the proteins whereas the earlier stages of vegetative body showed simpler profiles. The uptake of C-14 uracil into RNA and C-14 glutamate into protein were shown to be vigorous in presporulating body rather than those in sporulating body. Coincidence of alpha-amylase biosynthesis in de novo and sporulation may be significant in the study of differentiation in which gene expression is involved.

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Formation of biogenic amines and bioactivities of Makgeolli under different fermentation conditions (발효조건에 따른 막걸리의 Biogenic Amines(BAs)의 생성과 생리활성)

  • Kang, Seung Mi;Kim, Seon Jeong;Ko, Keon Hee;Nam, Sanghae
    • Food Science and Preservation
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    • v.23 no.3
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    • pp.402-412
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    • 2016
  • Generation of biogenic amines (BAs) and physiological activities of Makgeolli, Korean rice wine, were investigated during fermentation under different temperatures (20, 25, and $30^{\circ}C$) and time (3, 5, and 7 days). The pH was 3.96~4.36 during fermentation and the acidity increased proportionally with temperature and time. Alcohol and total phenolic contents peaked on day 5 at 25 by 9.0~9.8% and $3.01{\pm}0.07mg/g$, respectively. The organic acid mostly produced was lactic acid, which increased gradually with temperature and time. Formation of biogenic amines comprised of tryptamine and putrescine was observed during fermentation: 6.91, 11.70, and 15.63 mg/mL of tyramine on day 7 at 20, 25, and $30^{\circ}C$, respectively. Antioxidant activities from DPPH and FRAP assay were high in the order of $25^{\circ}C$>$20^{\circ}C$>$30^{\circ}C$ while that from ABTS assay was high regardless of temperature. Processed at 1 mg/mL and $30^{\circ}C$, the inhibitory effect on ${\alpha}$-amylase was $67.99{\pm}0.11$, $73.64{\pm}0.43$, and $75.51{\pm}0.26%$ on days 3, 5, and 7, respectively, which increased proportionally with temperature and time. Inhibitory activity on lipid accumulation in 3T3-L1 adipocytes was the highest in Makgeolli fermented on day 5 at $25^{\circ}C$. This study shows that fermentation at $25^{\circ}C$ for 5 days yields Makgeolli of the best quality with high bioactivities but no biogenic amines.

Characteristics of Byeo-Nuruk according to the Mixing Ratio of Wheat and the Addition Rate of Moisture (밀의 배합비율과 수분첨가율에 따른 벼누룩 품질특성)

  • Kim, Min-Seong;Jeon, Jin-A;Jeong, Seok-Tae;Choi, Ji-Ho;Choi, Han-Seok;Yeo, Soo-Hwan
    • Journal of the East Asian Society of Dietary Life
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    • v.21 no.6
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    • pp.897-904
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    • 2011
  • For set up the processing method of Byeo-Nuruk, we investigated the quality characteristics of Byeo-Nuruk according to the mixture ratio of rice and wheat, as well as the addition rate of moisture. After 12 hours of incubation, the temperature of Nuruk increased dramatically and reached a maxium temperature at 36 hours. After 36 hours, the temperature decreased gradually and was maintained at about $31{\sim}38^{\circ}C$. The ranges of pH and titratable acidity of Byeo-Nuruk were 4.85 to 7.42 and 1.0 to 2.3, respectively. A higher content of wheat ratio in Byeo-Nuruk, was associated with higher enzyme activities of ${\alpha}$-amylase, glucoamylase, and acidic-protease. Further, at a 70% wheat ratio, a 25% addition rate of moisture showed the highest enzyme activity. In the mixture ratio between rice and wheat, the 50:50 and 30:70 treatments contained the highest levels of microorganisms.

Cultural Characteristics of Fungi Strains isolated from Korean Nuruk (전통누룩에서 분리한 양조용 곰팡이의 배양 특성 연구)

  • Mun, Ji-Young;Baek, Seong-Yeol;Park, Hye-Young;Ro, Hyeon-Su;Yeo, Soo-Hwan
    • Journal of the East Asian Society of Dietary Life
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    • v.26 no.2
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    • pp.125-140
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    • 2016
  • We analyzed the cultural characteristics of isolated brewing fungi for developing fermentation starters. In a previous study, we collected 87 domestic nuruk, from which 481 fungi strains were isolated and 11 were selected showing improved productivity. After culturing these 11 fungi strains in several types of media, temperatures, carbon and nitrogen sources, Rhizopus sp. grew well in MEA, ME20S, PDA medium while Aspergillus sp. grew well in ME20S and YES. Both Rhizopus sp. and Aspergillus sp. survived well at optimal growth temperatures of 30 and $37^{\circ}C$. Rhizopus sp. utilized lactose, glucose and peptone sources while Aspergillus sp. utilized glucose, mannose, fructose and yeast extract sources. ${\alpha}-Amylase$ activity was excellent in L. ramosa CN044, R. oryzae 82-7(MEB), R. oryzae CN174 and A. oryzae 58-11(WEB) culture extracts. This study suggests that R. delemar 26-4, 58-8 and A. oryzae 78-5, 37-7 might be appropriate fungi strains for fermentation starters based on development of large fungi bodies and their good enzyme activities.

Identification of Differentially-Methylated Genes and Pathways in Patients with Delayed Cerebral Ischemia Following Subarachnoid Hemorrhage

  • Kim, Bong Jun;Youn, Dong Hyuk;Chang, In Bok;Kang, Keunsoo;Jeon, Jin Pyeong
    • Journal of Korean Neurosurgical Society
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    • v.65 no.1
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    • pp.4-12
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    • 2022
  • Objective : We reported the differentially methylated genes in patients with subarachnoid hemorrhage (SAH) using bioinformatics analyses to explore the biological characteristics of the development of delayed cerebral ischemia (DCI). Methods : DNA methylation profiles obtained from 40 SAH patients from an epigenome-wide association study were analyzed. Functional enrichment analysis, protein-protein interaction (PPI) network, and module analyses were carried out. Results : A total of 13 patients (32.5%) experienced DCI during the follow-up. In total, we categorized the genes into the two groups of hypermethylation (n=910) and hypomethylation (n=870). The hypermethylated genes referred to biological processes of organic cyclic compound biosynthesis, nucleobase-containing compound biosynthesis, heterocycle biosynthesis, aromatic compound biosynthesis and cellular nitrogen compound biosynthesis. The hypomethylated genes referred to biological processes of carbohydrate metabolism, the regulation of cell size, and the detection of a stimulus, and molecular functions of amylase activity, and hydrolase activity. Based on PPI network and module analysis, three hypermethylation modules were mainly associated with antigen-processing, Golgi-to-ER retrograde transport, and G alpha (i) signaling events, and two hypomethylation modules were associated with post-translational protein phosphorylation and the regulation of natural killer cell chemotaxis. VHL, KIF3A, KIFAP3, RACGAP1, and OPRM1 were identified as hub genes for hypermethylation, and ALB and IL5 as hub genes for hypomethylation. Conclusion : This study provided novel insights into DCI pathogenesis following SAH. Differently methylated hub genes can be useful biomarkers for the accurate DCI diagnosis.