• KSBB Journal
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• 제11권2호
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• pp.151-158
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• 1996

섬유소는 효소에 의한 가수분해에 의하여 유용한 화학물질이냐 연료 등으로 전환될 수 있다. 그러나 효소가 온도나 전단응력에 의해 쉽게 비활성화 되고 생성물인 당에 의한 억제 효과가 심각하기 때문에 효과적인 당화공정이 이루어지지 못하는 실정이다. 본 실험에서는 섬유소 가수분해에서의 두 효소, 즉 셀룰라아제 와 ${\beta}$-glucosidase의 통력학적 특정틀 을 이해하고, 생성물 억제영향 빛 효소의 비활성화 를 관찰하여, 섬유소의 고농도 당화 공정에 적용가 능한 통력학적 이론을 규명하고자 하였다. 셀룰라아제 벚 ${\beta}$-glucosidase는 다양한 통력학적 특정들을 보였으며, 반응기내에 5gN 의 포도당이 존재하여도 $\beta$glucosidase의 역가가 70% 이상 감소하는 것으로 나타나, 포도탕에 의한 ${\beta}$-glucosi­d dase의 억 제 영향이 가장 심각한 것으로 나타났다. 또한 셀로바이오스의 농도가 109/p 일때 역시 셀롤 라야제의 역가가 약 70% 감소하였다. ${\beta}$-glucosi dase의 경우 셀룰라아제와 비교하여 약 1.6배 정도 비활성화에 더 민강한 것으로 밝혀졌다. 당화 공정 모사 결과는 대체척으로 신뢰할 수 있는 범위의 결 과를 얻었으며, 가수분해가 진행되는동안 실험결과 와 모사에 의한 계산값은 잘 일치하였다.

• 생명과학회지
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• 제20권11호
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• pp.1589-1594
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• 2010

Exiguobacterium sp. 유래의 $\beta$-glucosidase 고정을 위하여 글루타르알데하이드를 사용한 키토산 비드를 조제하였다. 키토산 비드의 교차결합 및 고정화의 조건을 최적화하였다. $\beta$-glucosidase 고정화의 최적생산 조건에서 20%의 수율과 5.22 U/g의 효소활성을 나타냈다. 최적 pH 와 온도는 9.0과 $55^{\circ}C$를 나타냈다. 고정된 효소의 안정성은 pH 7.0-10.0에서는 80%, $40^{\circ}C$ 2시간 반응에서는 80% 및 $50^{\circ}C$ 1시간 반응에서는 48%의 활성을 보유하였다. 이러한 결과는 높은 pH와 고온에서 비고정 효소보다 안정성을 보여주었다. 고정된 효소를 가지고 대두 이소플라본 배당체의 높은 가수분해능을 확인하였다. 이상의 결과는 고정화 효소의 다양한 이용 가능성을 시사하였다.

• 한국식품영양학회지
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• 제14권6호
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• pp.591-595
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• 2001

참깨 탈지박에 다량존재하는 수용성 lignan화합물을 $\beta$-glucosidase로 처리하여 얻어진 참깨박 추출물의 항산화 효과 및 기존 항산화제들과의 상승효과를 비교, 검토하고자 하였다. 참깨박 추출물 중에서도 sesamin 및 sesamolin이 peak가 확인되었으며, 각각 8.32%(8,315.4mg/100g) 및 0.28%(2,824.5mg/100g)의 함량을 나타냈다. Sesamin과 sesamolin은 배당체의 aglycone으로서 탈지박 중에 존재하는 것으로 나타났다. 참깨박 추출물의 항산화효과는 첨가농도가 증가함에 따라 증가되었으며, 이들의 효과는 같은 농도(100ppm)의 $\alpha$-tocopherol이나 ascorbyl palmitate 첨가구보다 항산화효과가 우수하였으나 BHA보다는 다소 약한 효과를 보였다. 또한 가수분해 물은 $\alpha$-tocopherol과 강한 상승 작용을 보여주었으나 ascorbyl palmitate와는 비교적 약한 상승작용을 나타내었다.

• 한국식품영양학회지
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• 제11권5호
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• pp.488-492
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• 1998

This study was performed to investigate the influcence of various dietary fiber sources in Korea for activities of bacterial enzymes (${\beta}$-glucosidase, ${\beta}$-glucuronidase) and amounts of putrefactive product (indole) in aged rats. ${\beta}$-Glucosidase activity in the intestinal content was significantly lower in the seamustard 15% group than in other groups whereas the activity of ${\beta}$-glucuronidase was higher in the mugwort 15% group than other experimental groups. The amount of indole and pH in the intestinal content of aged rats were significantly lower in mugwort groups than in other groups.

• 미생물학회지
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• 제24권3호
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• pp.251-262
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• 1986

High-molecular-weight ${\beta}-glucosidase$ (EC 3.2.1.21) was purified from the culture filtrate of Trichoderma koningii through a four-step procedure including chromatography on Bio-Gel P-150, DEAE-Sephadex A-50 and SP-Sephadex C-50; and chromatofocusing on Polybuffer exchanger PBE 94. The molecular weight of the enzyme was determined to be about 101,000 by SDS-polyacrylamide gel electrophoreses, and the isoelectric point was estimated to be 4.96 by analytical isoelectric focusing. The temperature optimum for activity was about $55^{\circ}C$, and the pH optimumwas 3.5. The enzyme was considerably thermostable, for no loss of activity was observed when the enzyme was preincubated at $60^{\circ}C$ for 5h. Km values for cellobiose, gentiobiose, sophorose, salicin and $p-nitrophenyl-{\betha}-D-glucoside$ were 99.2, 14.7, 7.09, 3.15 and 0.70 mM, respectively, which indicates that the enzyme has much higher affinity towards $p-nitrophenyl-{\betha}-D-glucoside$ than towards the other substrates, especially cellobiose. Substrate inhibition by $p-nitrophenyl-{\betha}-D-glucoside$ and salicin was observed at the conecntrations exceeding 5mM. Gluconolactone was a powerful inhibitor against the action of the enzyme on $p-nitrophenyl-{\betha}-D-glucoside\;(K_i\;37.9\;{\mu}M)$, wherease glucose was much less effective ($K_i$ 1.95 mM). Inhibition was of the competitive type in each case. Transglucosylation activity was detected shen the readtion products formed from $p-nitrophenyl-{\betha}-D-glucoside$ by the enzyme were analysed using high-performance liquid chromatography.

• 한국식품조리과학회지
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• 제26권2호
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• pp.214-219
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• 2010

In this study, phytoestrogen for the industrial production of soybean probiotics by lactic acid bacteria (LAB) was studied in a soybean extract. Soybean was fermented with LAB, Lactobacillus plantarum KCTC 3108 and Bifidobacterum longum ATCC 15707. The change in the content of various isoflavones (aglycone and glucoside) and the $\beta$-glucosidase activity in soybean during fermentation were investigated and shown to be dependent on the starter organism. Soybean extract powder fermented with L. plantarum showed the highest $\beta$-glucosidase activity and the greatest increase in the aglycone content. After 48h of fermentation, the contents of daidzin, genistin and glycitin in L. plantarum decreased from a mean initial levels of $83.03{\pm}2.17$, $168.13{\pm}8.17$ and $20.02{\pm}1.07$, respectively, to mean levels of $5.34{\pm}3.24$, $3.79{\pm}0.57$ and $1.87{\pm}1.09\;mg$/100 g. Whereas, after 48h fermentation, the contents of daidzein, genistein and glycitein increased from a mean initial levels of $8.09{\pm}0.78$, $11.20{\pm}0.84$ and $4.71{\pm}0.46$, respectively, to mean levels of $85.76{\pm}0.84$, $175.87{\pm}2.21$ and $22.41{\pm}0.91\;mg$/100 g. Taken together, these results suggested an increase of aglycones and decrease of glucoside in isoflavones occurred during fermentation, which coincided with an increase of $\beta$-glucosidase activity in the fermented soybean extract powder.

• 생명과학회지
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• 제27권2호
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• pp.172-179
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• 2017

본 연구는 몽골 마유로부터 분리한 유산균 Enterococcus faecium SA5의 이화학 특성을 파악하고 유산균 E. faecium SA5의 ${\beta}$-glucosidase의 활성과 이를 통한 ginsenoside 전환을 확인하는 것을 목표로 진행되었다. E. faecium SA5는 내산성, 내담즙성을 나타내었으며 4종의 병원성 미생물(Salmonella typhimurium KCTC 3216, Listeria monocytogenes KCTC 3710, Bacillus cereus KCTC 1012, Staphylococcus aureus KCTC 1621)에 항균 활성을 가질 뿐만 아니라 항생물질 colistin, gentamycin, neomycin에 내성을 나타내었다. 또한, E. faecium SA5는 bile salt hydrolase 활성을 나타내어 혈액 내 콜레스테롤 수준 감소 효과가 있다고 사료되며 10% skim milk에서 배양하였을 때, pH가 감소하고 산도 및 생균수가 증가하는 것으로 보아 발효유 스타터로써의 활성을 갖는 것으로 판단되었다. 또한 E. faecium SA5의 ${\beta}$-glucosidase에 의해 ginsenoside $Rb_1$이 ginsenoside $Rg_3-s$와 $Rg_3-r$으로 전환되었음을 TLC 분석을 통해 확인하였다. 따라서 E. faecium SA5는 잠재적인 probiotics로 이를 이용하여 발효유 제조 및 ginsenoside 전환 관련 건강기능식품 개발에 응용할 수 있을 것으로 사료된다.

• Journal of Microbiology and Biotechnology
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• 제17권11호
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• pp.1789-1796
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• 2007

A ${\beta}$-glucosidase with the molecular mass of 160,000 Da was purified to homogeneity from cell extract of a cellulolytic bacterium, Cellulomonas uda CS1-1. The kinetic parameters ($K_m$ and $V_{max}$) of the enzyme were determined with pNP-cellooligosccharides (DP 1-5) and cellobiose. The molecular orbital theoretical studies on the cellulolytic reactivity between the pNP-cellooligosaccharides as substrate (S) molecules and the purified ${\beta}$-glucosidase (E) were conducted by applying the frontier molecular orbital (FMO) interaction theory. The results of the FMO interaction between E and S molecules verified that the first stage of the reaction was induced by exocyclic cleavage, which occurred in an electrophilic reaction based on a strong charge-controlled reaction between the highest occupied molecular orbital (HOMO) energy of the S molecule and the lowest occupied molecular orbital (LUMO) energy of the hydronium ion ($H_3O^+$), more than endocyclic cleavage, whereas a nucleophilic substitution reaction was induced by an orbital-controlled reaction between the LUMO energy of the oxonium ion ($SH^+$) protonated to the S molecule and the HOMO energy of the $H_2O_2$ molecule. A hypothetic reaction route was proposed with the experimental results in which the enzymatic acid-catalyst hydrolysis reaction of E and S molecules would be progressed via $SN_1$ and $SN_2$ reactions. In addition, the quantitative structure-activity relationships (QSARs) between these kinetic parameters showed that $K_m$ has a significant correlation with hydrophobicity (logP), and specific activity has with dipole moment, respectively.

• 한국미생물생명공학회:학술대회논문집
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• 한국미생물생명공학회 1986년도 추계학술대회
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• pp.525.1-525
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• 1986

To clone ${\beta}$-glucosidase gene from Cellulomonas sp. a gene library was constructed using E. coli JM83 pUC9. Among 2,500 pseudotransformants obtained, 20 clones developed yellow color on the p-nitrophenyl- -D-glucopyranoside filter paper These 20 clones were classified into three groups based on the results of activity staining using nondenaturating polyacrylamide gel electrophoresis and restriction enzyme digestions. Among the three groups, only one group containing pCEl plasmid has specificity for cellobiose.

• KSBB Journal
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• 제13권1호
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• pp.20-25
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• 1998

Optimum conditions of the cellulose-hydrolysis reaction with mixed enzymes(cellulase extracted from Penicellium funiculosum mixed with $\beta$-glucosidase extracted from Almod) were investigated to increase the production of glucose from cellulose. Experimental result showed that optimum conditions fro pH, activity ratio of $\beta$-glucosidase to cellulase, concentration of mixed enzymes, concentration of cellulose as a substrate, and temperature range were 4.2, 0.4, 0.8, U/mL, 40 g/L, and 37$\pm$3$^\circ C$, respectively. In these conditions, quantities of glucose productions by using mixed enzymes were larger than those by using cellulase at optimum conditions.