• 미생물학회지
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• 제26권2호
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• pp.122-128
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• 1988

The enzymatic properties of soil cellobiohydrolase were examined and compared with those of cellobiohydrolase-active extracts from soil in the forms of enzyme-humic complex and humicfree enzyme, and cellobiohydrolase partially pruified from Aspergillus niger. The pH optima of soil cellobiohydrolase and cellobiohydrolase-humic complex were greater by 1.5-3.0 pH units than those of cellobiohydrolase in humic-free extract and from A. niger. Soil cellobiohydrolase and cellobiohydrolase-humic complex were remarkably resistant to thermal denaturation and proteolysis. These results confirm that cellobiohydrolase in soil is atable in conditions which rapidly inactivate microbial cellobiohydrolase and that its stability is due to the immobilization of this enzyme by association with humic substances. The Michaelis-Menten constants (Km) for soil, cellobiohydrolase-humic complex, humic free extract and cellobiohydrolase from A. niger were 22.1mg/ml, 11.3mg/ml, 10.6mg/ml and 4.5 mg/ml of Avicel, respectively.

• Asian-Australasian Journal of Animal Sciences
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• 제17권4호
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• pp.523-532
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• 2004

An experiment was conducted to investigate the effect of microbial phytase ($Natuphos^{R}$) supplementation in combination with enzyme complex (composed of enzymes targeted to SBM dietary components such as $\alpha$-galactosides and galactomannans; $Endo-Power^{R}$) to diet with low nutrient levels on growth performance and ileal nutrient digestibility of weaned pigs. A total of 210 crossbred weaned pigs (Landrace$\times$Yorkshire$\times$Duroc), 6.68$\pm$0.98 kg of initial body weight, were randomly allotted to five dietary treatments, based on weight and age, according to a randomized complete block design. There were three pens per treatment and 14 pigs per pen. The dietary treatments were 1) CON (Control diet with no phytase and enzyme complex (EC)), 2) LP+EC 100 (Control diet with 0.15% unit lower available phosphorus (aP) level+0.1% phytase (500 FTU/kg diet) and 0.1% enzyme complex), 3) LP+EC 80 (Control diet with 0.15% unit lower aP level+0.08% phytase (400 FTU/kg diet) and 0.08% enzyme complex, 4) LPEA+EC 100 (Control diet with 0.15% unit lower aP and 3% lower ME and amino acid levels (lysine, methionine, threonine and typtophan)+0.1% phytase (500 FTU/kg diet) and 0.1% enzyme complex), 5) LPEA+EC 80 (Control diet with 0.15% unit lower aP and 3% lower ME and amino acid levels+0.08% phytase (400 FTU/ kg diet) and 0.08% enzyme complex). For the determination of ileal nutrients digestibility, a total of 15 T-cannulated pigs (initial body weight; 7.52$\pm$1.24 kg; 3 replicates per treatment) were used in the present study. Piglets were weighted and allotted into same dietary treatments as one in growth trial and phase I experimental diets were provided for ileal digestibility study. There was no significant difference (p>0.05) in average daily gain (ADG) and average daily feed intake (ADFI) among dietary treatments during the whole experimental period (0 to 5 weeks). However, piglets in LP+EC 100 group had a significantly higher gain/feed ratio (G:F) than piglets had in control (p<0.05). Crude protein, energy and phosphorus digestibilities were significantly improved when both of phytase and enzyme complex were supplemented at the revel of 0.1%, respectively to diets with low nutrient level (aP or (and) ME and amino acids) (p<0.05). Piglets in LP+EC 100 and LPEA+EC 100 groups showed significantly higher phosphorus content (%) in bone than that of piglets in control group (p<0.05). Supplementation of both of phytase and enzyme complex at 0.1%, respectively, to diet with low nutrient levels (aP or (and) ME and amino acids) significantly improved total ileal essential amino acid and nonessential amino acid digestibilities compared to control group (p<0.05). In conclusion, the results from the present study suggest that the simultaneous inclusion of phytase and enzyme complex to diets at recommended level is advantageous with respect to improving growth performance and nutrient digestibility of weaned pigs and may contribute to increased economic return when added to corn-soy based weaned pig diets.

• Journal of Microbiology and Biotechnology
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• 제20권2호
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• pp.254-264
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• 2010

To obtain an efficient natural lignocellulolytic complex enzyme, we screened an efficient lignocellulose-degrading composite microbial system (XDC-2) from composted agricultural and animal wastes amended soil following a long-term directed acclimation. Not only could the XDC-2 degrade natural lignocelluloses, but it could also secrete extracellular xylanase efficiently in liquid culture under static conditions at room temperature. The XDC-2 degraded rice straw by 60.3% after fermentation for 15 days. Hemicelluloses were decomposed effectively, whereas the extracellular xylanase activity was dominant with an activity of 8.357 U/ml on day 6 of the fermentation period. The extracellular crude enzyme noticeably hydrolyzed natural lignocelluloses. The optimum temperature and pH for the xylanase activity were $40^{\circ}C$ and 6.0. However, the xylanase was activated in a wide pH range of 3.0-10.0, and retained more than 80% of its activity at $25-35^{\circ}C$ and pH 5.0-8.0 after three days of incubation in liquid culture under static conditions. PCR-DGGE analysis of successive subcultures indicated that the XDC-2 was structurally stable over long-term restricted and directed cultivation. Analysis of the 168 rRNA gene clone library showed that the XDC-2 was mainly composed of mesophilic bacteria related to the genera Clostridium, Bacteroides, Alcaligenes, Pseudomonas, etc. Our results offer a new approach to exploring efficient lignocellulolytic enzymes by constructing a high-performance composite microbial system with synergistic complex enzymes.

• Journal of Microbiology and Biotechnology
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• 제32권6호
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• pp.749-760
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• 2022

α-Galactosidase is a debranching enzyme widely used in the food, feed, paper, and pharmaceuticals industries and plays an important role in hemicellulose degradation. Here, T26, an aerobic bacterial strain with thermostable α-galactosidase activity, was isolated from laboratory-preserved lignocellulolytic microbial consortium TMC7, and identified as Parageobacillus thermoglucosidasius. The α-galactosidase, called T26GAL and derived from the T26 culture supernatant, exhibited a maximum enzyme activity of 0.4976 IU/ml when cultured at 60℃ and 180 rpm for 2 days. Bioinformatics analysis revealed that the α-galactosidase T26GAL belongs to the GH36 family. Subsequently, the pET-26 vector was used for the heterologous expression of the T26 α-galactosidase gene in Escherichia coli BL21 (DE3). The optimum pH for α-galactosidase T26GAL was determined to be 8.0, while the optimum temperature was 60℃. In addition, T26GAL demonstrated a remarkable thermostability with more than 93% enzyme activity, even at a high temperature of 90℃. Furthermore, Ca²⁺ and Mg²⁺ promoted the activity of T26GAL while Zn²⁺ and Cu²⁺ inhibited it. The substrate specificity studies revealed that T26GAL efficiently degraded raffinose, stachyose, and guar gum, but not locust bean gum. This study thus facilitated the discovery of an effective heat-resistant α-galactosidase with potent industrial application. Meanwhile, as part of our research on lignocellulose degradation by a microbial consortium, the present work provides an important basis for encouraging further investigation into this enzyme complex.

• Journal of Animal Science and Technology
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• 제66권2호
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• pp.398-411
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• 2024

Upregulation of the nutritional value of feed is the major target of various studies in the livestock industry, and dietary enzyme supplementation could aid in digesting the nondegrading nutrients of grains in feed ingredients. Dried distillers' grains with solubles (DDGS) is a byproduct of the fermentation process in the beverage industry and can be used as a large supply source of fiber in feed. Therefore, we conducted an experiment with male broiler chickens to investigate the effect of various types of enzymes on DDGS and compare the efficacy of single enzyme and multienzyme complexes on growth performance and gut environments in broiler chickens. We used 420 1-day-old broiler chickens (Ross 308), and they were allotted into 4 dietary treatments with seven replications (CON, corn-soybean meal [SBM] diet; NC, DDGS supplemented diet; SE, 0.05 % of mannanase supplemented DDGS-based diet; MC, 0.10% of multienzyme complex (mannanase and xylanase, glucanase) supplemented DDGS-based diet. The dietary exogenous enzyme in the DDGS-supplemented diet could improve growth performance as much as the growth of the control group, and digestibility of dry matter, crude protein, and gross energy were significantly increased by enzyme addition in groups of chicks fed DDGS-supplementation diet. Moreover, the populations of pathogenic bacteria, coliforms, and Bacteroidetes were significantly decreased by enzyme supplementation, which might lead to improved gut mucus-secreting cells and inflammatory cytokines in the jejunum. Collectively, dietary single enzyme and multienzyme complexes could improve gut environments, including intestinal immune responses and gut microbial population, and lead to improvement of growth performance in broiler chickens.

• 한국미생물생명공학회:학술대회논문집
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• 한국미생물생명공학회 1986년도 추계학술대회
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• pp.506-508
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• 1986

Metabolic activity of inorganic nitrogenous compounds affects not only microbial growth but also metabolite production in fermentation technology. We have worked on the enzymes participating in ammonia assimulation of some fermentation bacteria. This paper summarizes the results on glutamine synthetase and its application in practical field. Glutamine synthetase (L-glutamate:ammonia ligase, EC. 6.3.1.2) catalyzes the formation of glutamine from glutamate and ammonia at the expense of cleavage of ATP and inorganic phosphate. The enzyme plays a dual role in nitrogen metabolism in bacteria; it is a key enzyme not only in the biosynthesis of various compounds through glutamine but also in the regulation of synthesis of some enzymes involved in the metabolism of nitrogenous compounds. The detailed works with the Eschericia coli and other enterobacterial enzymes revealed that glutamine synthetase is controlled by the following complex of mechanisms: (a) feedback inhibition by end products, (b) repression and derepression of enzyme synthesis, (c) modulation of enzyme activity in response to divalent cation and (d) covalent modification of enzyme protein by adenylylation and its cascade control. Comparative studies have also been made on the enzymes from other organisms.

• KSBB Journal
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• 제17권4호
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• pp.381-387
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• 2002

본 연구의 목적은 기존의 단일 균주보다 두 종의 서로 다른 균주를 복합시켰을 때 두 균주간의 상호 보완적인 면을 이용하여 효소생산을 극대화하기 위함이며, 다음과 같은 결론을 얻었다. 실험에서 사용된 T viride와 FB01는 최적 PH와 온도가 비슷하여 혼합배양이 가능하였으며, 이들의 복합균주를 개발하는데 성공하였다. 즉 두 균주는 회분배양 하였을 때, 서로의성장속도에 차이가 있었기 때문에 두 균주의 생장균형을 유지하기 위해 접종시기를 조절할 필요가 있었다. 접종시기를 변화시킴으로서 두 균주간의 상호작용으로 인해 단일 균주일때보다 CMCase, $\beta$-glucosidase 및 avicelase의 활성이 우수했으며 또한 계대배양을 통한 두 균주의 활성유지에 관한 실험에서는 pH 조절을 통해 $\beta$-glucosidase 활성이 최고 3.2배까지증가함을 알 수 있었다. 따라서 배양액내에서 초기 pH의 영향은 생산된 cellulase complex의 다양한 구성요소의 상대적인 농도를 결정하는 실질적인 요인으로 판명된다. pH 4.5에서의 enzyme activity는 12.5 U/mL CMCase, 2.46 U/mL If-glucosidase, 0.93 U/mL avicelase였으며 개발당시의 복합균주활성인, 2.04 U/ml CMCase, 0.78U/ml $\beta$-glucosidase, 0.2 U/mL avicelase과 비교할 때 각각 6, 3.2, 4.7배의 높은 활성을 보였다. 복합균주의 탄소원으로 볏짚을 이용했을 때 복합균주에 의한 효소생산이 단일 균주인 T. virile나 FB01보다 훨씬 높게 나타났으며, 이때의 볏짚의 최적 농도는 5%(w/v)였다. 이러한 배양조건에서 복합균주를 장기적으로 계대배양하면서 효소의 생산성 향상과 복합균주의 안정성을 관찰할 필요가 있다고 사료된다.

• 한국식품저장유통학회지
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• 제30권2호
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• pp.287-299
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• 2023

효소 및 미생물 복합제를 사용하여 인비트로 발효 루왁커피를 제조하여 non-fermented coffee beans(NFC)과 fermented coffee beans(FC)의 커피 품질을 비교하였다. 총유리아미노산 함량은 NFC가 254.01±4.89 mg/mL, FC가 264.15±16.80 mg/mL로 FC의 함량이 다소 높은 것으로 확인되었다. 이때 NFC는 glutamic acid, γ-aminon-butyric acid 등이 높았으나, FC는 lysine, leucine, valine 등 필수아미노산의 함량이 높았다. 커피 생두의 발효과정은 sucrose의 감소와 fructose 및 glucose의 유의적인 증가를 가져왔다. 커피 추출물의 색도는 NFC에 비해 FC 시료에서 높은 명도(L)와 적색도(a) 및 황색도(b)를 보였다. 카페인 함량은 NFC 1,130.22±1.55 ㎍/mL, FC 696.94±0.04 ㎍/mL로써 발효 후 약 38%의 카페인이 감소되었다. 폴리페놀 및 클로로겐산 함량은 NFC에서 각각 2.31±0.01 mg GAE/mL와 531.81±27.32 ㎍/mL, FC에서 각각 2.03±0.07 mg GAE/mL와 264.46±2.47 ㎍/mL로 발효에 따라 떫은맛 관련 성분의 함량이 유의적으로 감소됨을 알 수 있었다. 전자코 분석에서 NFC와 FC의 휘발성 향성분의 차이가 뚜렷함이 확인되었고, methylethyl formate, 2-methyl-1, 3-cyclopentadiene, 2-chloro-2-methylbutane, 2-methylbutanal 등의 휘발성 화합물이 발효 후 높은 강도로 감지되었다. 관능 평가에서는 NFC 추출물보다 FC 추출물의 aroma, body, aftertaste, overall에서 높은 관능 평점을 보여주었다(p<0.001). 이상의 결과에서 효소 및 미생물 복합제를 사용한 커피 생두의 발효는 유효 성분들의 변화를 일으켜 커피 원두의 로스팅 과정 중 Maillard 반응을 촉진함으로써, 향미가 증가되고 카페인 함량이 감소된 인비트로 루왁 커피의 제조 가능성을 시사하였다.

• Ecology and Resilient Infrastructure
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• 제4권2호
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• pp.93-96
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• 2017

Spatial variations of physicochemical and microbiological variables were examined to understand spatial heterogeneity of those variables in intertidal flat. Variograms were constructed for understanding spatial autocorrelations of variables by a geostatistical analysis and spatial correlations between two variables were evaluated by applications of a Cross-Mantel test with a Monte Carlo procedure (with 999 permutations). Water content, organic matter content, pH, nitrate, sulfate, chloride, dissolved organic carbon (DOC), four extracellular enzyme activities (${\beta}-glucosidase$, N-acetyl-glucosaminidase, phosphatase, arylsulfatase), and bacterial diversity in soil were measured along a transect perpendicular to shore line. Most variables showed strong spatial autocorrelation or no spatial structure except for DOC. It was suggested that complex interactions between physicochemical and microbiological properties in sediment might controls DOC. Intertidal flat sediment appeared to be spatially heterogeneous. Bacterial diversity was found to be spatially correlated with enzyme activities. Chloride and sulfate were spatially correlated with microbial properties indicating that salinity in coastal environment would influence spatial distributions of decomposition capacities mediated by microorganisms. Overall, it was suggested that considerations on the spatial distributions of physicochemical and microbiological properties in intertidal flat sediment should be included when sampling scheme is designed for decomposition processes in intertidal flat sediment.

• Journal of Microbiology and Biotechnology
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• 제31권8호
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• pp.1123-1133
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• 2021

Biodegradation is the key process involved in natural lignocellulose biotransformation and utilization. Microbial consortia represent promising candidates for applications in lignocellulose conversion strategies for biofuel production; however, cooperation among the enzymes and the labor division of microbes in the microbial consortia remains unclear. In this study, metagenomic analysis was performed to reveal the community structure and extremozyme systems of a lignocellulolytic microbial consortium, TMC7. The taxonomic affiliation of TMC7 metagenome included members of the genera Ruminiclostridium (42.85%), Thermoanaerobacterium (18.41%), Geobacillus (10.44%), unclassified_f__Bacillaceae (7.48%), Aeribacillus (2.65%), Symbiobacterium (2.47%), Desulfotomaculum (2.33%), Caldibacillus (1.56%), Clostridium (1.26%), and others (10.55%). The carbohydrate-active enzyme annotation revealed that TMC7 encoded a broad array of enzymes responsible for cellulose and hemicellulose degradation. Ten glycoside hydrolases (GHs) endoglucanase, 4 GHs exoglucanase, and 6 GHs β-glucosidase were identified for cellulose degradation; 6 GHs endo-β-1,4-xylanase, 9 GHs β-xylosidase, and 3 GHs β-mannanase were identified for degradation of the hemicellulose main chain; 6 GHs arabinofuranosidase, 2 GHs α-mannosidase, 11 GHs galactosidase, 3 GHs α-rhamnosidase, and 4 GHs α-fucosidase were identified as xylan debranching enzymes. Furthermore, by introducing a factor named as the contribution coefficient, we found that Ruminiclostridium and Thermoanaerobacterium may be the dominant contributors, whereas Symbiobacterium and Desulfotomaculum may serve as "sugar cheaters" in lignocellulose degradation by TMC7. Our findings provide mechanistic profiles of an array of enzymes that degrade complex lignocellulosic biomass in the microbial consortium TMC7 and provide a promising approach for studying the potential contribution of microbes in microbial consortia.