• 한국식품과학회지
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• 제47권5호
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• pp.545-555
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• 2015

Oxyresveratrol (trans-2,3',4,5'-tetrahydroxystilbene) has been receiving increasing attention because of its astonishing biological activities, including antihyperlipidemic, neuroprotection, antidiabetic, anticancer, antiinflammation, immunomodulation, antiaging, and antioxidant activities. Oxyresveratrol is a stilbenoid, a type of natural phenol and a phytoalexin produced in the roots, stems, leaves, and fruits of several plants. It was first isolated from the heartwood of Artocarpus lakoocha, and has also been found in various plants, including Smilax china, Morus alba, Varatrum nigrum, Scirpus maritinus, and Maclura pomifera. Oxyresveratrol, an aglycone of mulberroside A, has been produced by microbial biotransformation or enzymatic hydrolysis of a glycosylated stilbene mulberroside A, which is one of the major compounds of the roots of M. alba. Oxyresveratrol shows less cytotoxicity, better antioxidant activity and polarity, and higher cell permeability and bioavailability than resveratrol (trans-3,5,4'-trihydroxystilbene), a well-known antioxidant, suggesting that oxyresveratrol might be a potential candidate for use in health functional food and medicine. This review focuses on the plant sources, chemical characteristics, analysis, biosynthesis, and biological activities of oxyresveratrol as well as describes the perspectives on further exploration of oxyresveratrol.

• 대한화장품학회:학술대회논문집
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• 대한화장품학회 2003년도 IFSCC Conference Proceeding Book I
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• pp.35-49
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• 2003

In this study, in an attempt to search for functional cosmetic ingredients from higher fungal, we have produced exopolysaccharides (GF-l, approximately carbohydrate 75％, protein 25％) and polysaccharide (GF-2) of mycelium extract, by submerged culture of Grifolafrondosa. For applications in anti-aging cosmetic field, we investigated the diverse biological activities. Antioxidant activity and inhibition of Matrixmetalloproteinases (MMPs) were investigated enzymatic assays by measuring the superoxide scavenging activity using xanthine-xanthine oxidase system and the proteolytic activity of MMPs using EnzChek Collagenase/Gelatinase kits, respectively. GF-l polysacchairde showed inhibition of superoxide radical by 90％ at a concentration of 0.2％ (w/v) and inhibition of collagenase by 45％ at 0.2％ (w/v). GF-2 polysaccharide of mycelium extract also exhibited good antioxidant activity. However, MMPs inhibition activity was relatively lower level compared to GF-l polysaccharides. The treatment of human dermal fibroblast (HDF) with GF-l and GF-2 polysaccharides increased the proliferation of fibroblast by approximately 23-25％ at a concentration of 0.5％ (w/v), also showed collagen synthesis increase in HDF by about 50％ at 0.5％ (w/v) compared to that of untreated control. We also report the moisturizing effects of polysaccharides in cosmetic products (O/W emulation) and its own ingredient, in vitro and in vivo. The GF-1 polysaccharide showed higher moisturizing ability than sodium hyaluronate, which is the most commonly used moisturizers ingredient. These results suggest the GF-l polysaccharide, protein-bound polysaccharide, may be used as an ingredient for new moisturizing and anti-aging cosmeceuticals.

• Journal of the Korean Wood Science and Technology
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• 제15권4호
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• pp.18-25
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• 1987

섬유성 물질을 자화(資化)하는 미생물을 자연계로 부터 분리하여 효소생산 및 당화조건을 검토하였다. 분리 균주 256주 중 효소생산에 가장 유효하다고 인정되는 Aspergillus fumigatus KC-1을 우수 균주로 선발하였다. 본 균은 alkaline peroxide로 전처리한 현사시 목분 1%를 탄소원으로하여 $45^{\circ}C$에서 진탕 배양시 4~5일째 효소생성(여지, Avicel, 탈지면, CMC, Salicine 및 Xylan 당화활성)이 최고치에 달했다. 효소의 최적 pH는 4.5, 최적온도는 $60^{\circ}C$였다. 본 균의 효소에 의한 현사시 목분의 가수 분해시 1 % NaOH와 20% 과초산으로 탈리그닌한 목분의 가수 분해율이 가장 높았고, 최종 산물로 glucose와 약간의 cellobiose 및 xylose가 검출되었다. 따라서 본균의 cellulase는 cellulose를 쉽게 glucose로 당화하는데 매우 유효한 효소로 판단되었다. 현사시 목분의 효소분해에 대한 탈리그닌 정도, 기질의 크기 및 농도의 영향도 아울러 검토하였다.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2002년도 생물공학의 동향 (X)
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• pp.457-460
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• 2002

In an effort to isolate novel strains expressing a thermostable esterase that hydrolyzed the rac-ketoprofen ethyl ester to ketoprofen in the stereospecific manner, we screened various soils and composts from broad ecological niches in which the activity was expected to be found. Three hundreds of microbial strains were tested to determine their ester-hydrolyzing activity by using an agar plate containing insoluble tributyrin as an indicative substrate, and then further screened by activity on the (R,S)-ketoprofen ethyl ester. Twenty-six strains were screened primarily at high growth and incubation temperature and further compared the ability to ethyl ester-hydrolyzing activity in terms of conversion yield and chiral specificity. Consequently, a strain JYl44 was isolated as a novel strain that produced a (R)-stereospecific esterase with high stability and systematically identified as a Bacillus stearothermophilus JY144. The enzyme indeed stables at a broad range of temperature, upto 65 $^{\circ}C$, and pH ranging from 6.0 to 10.0. The optimal temperature and pH for enzymatic conversion were 50 $^{\circ}C$ and 9.0, respectively. Based on the observations that resulted a poor cell growth, and enzyme expression in wild type strain, we further attempted the gene cloning into a general host Escherichia coli and determined its primary structure, concomitantly resulting a high level expression of the enzyme. The cloned gene had an open reading frame (250 amino acids) with a calculated molecular mass of 27.4 kDa, and its primary structure showed a relative high homology (45-52 %) to the esterases from Streptomyces and Bacillus strains. The recombinant whole cell enzyme could efficiently convert the rac-ketoprofen ethyl ester to (R)-ketoprofen, with optical purity of 99 % and yield of 49 %.

• 한국식품과학회지
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• 제10권4호
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• pp.380-386
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• 1978

Streptomyces spp. K-14에서 생성되는 포도당 이성화효소의 특성에 대해서 연구하였다. 효소 반응의 최적 pH와 온도는 5 mM $MgSO_4{\cdot}7H_2O$와 2 mM $CoCl_2{\cdot}6H_2O$의 존재 아래에 각각 $7.5{\sim}8.0$ 그리고 $70^{\circ}{\sim}75^{\circ}C$로 나타났다. 이러한 이성화 효소는 $Mg^{++}$과 $Co^{++}$두 양이온에 의하여 활성화 되었는데 $Mg^{++}$는 이성화 반응의 초기 활성화에 소요 되었으며 $Co^{++}$는 효소 단백질을 안정화 하는데 소요 되었다. 포도당 농도 60%까지는 효소 반응속도나 효소의 이성화율에 영향을 끼치지 않았다.

• 생태와환경
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• 제35권4호통권100호
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• pp.266-272
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• 2002

팔당호에 설치된 인공식물섬에서 미생물의 역할을 알아보기 위하여 동물플랑크톤 군집 크기, 총세균수, 활성세균수, ${\beta}$-glucosidase와 phosphatase의 체외효소활성도를 2001년 11월 3일부터 2002년 4월까지 격주로 인공식물섬이 설치된 지역과 바깥지역을 대상으로 조사 분석하였다 인공식물섬 아래에서는 일반적으로 측정하는 환경요인들은 대조구보다 수질이 나쁜 것으로 나타났다. 그러나, 동물 플랑크톤의 수는 대조구보다 굉균 25배, 활성세균의 수는 평균 3-8배, 그리고 체외효소활성도는 훨씬 높은 값을 보였다. 이러한 결과는 인공식물섬에서는 동물플랑크톤-식물플랑크톤-수초-세균의 밀접한 관계가 존재하고, 이 관계에 의하여 동물플랑크톤과 세균의 호흡, 분해작용으로 유기물이 제거되는 것으로 판단되었다.

• 한국식품저장유통학회지
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• 제19권3호
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• pp.323-327
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• 2012

신선절단 '쓰가루' 사과의 갈변과 미생물 성장 저해에 대해 ascorbic acid와 초음파 처리의 효과를 조사하였다. 사과를 8조각으로 자르고, 1분간 증류수에 침지(Cont), 1분 동안 1% ascorbic acid에 침지(AA), 1분 동안 초음파 처리(US), 또는 1분 동안 1% ascorbic acid용액으로 초음파 처리(AA+US) 후 0.04 mm polypropylnene film으로 열접합 포장하고, 8일 동안 $10^{\circ}C$에서 저장하면서 품질 변화를 분석하였다. AA+US 처리구에서 저장 마지막 날까지 가장 높은 $L^*$값과 낮은 $a^*$, $b^*$값을 보였고, polyphonoloxidase 활성 또한 가장 억제 된 것으로 나타났다. 총균수의 변화는 저장 초기부터 마지막 날까지 AA+US 처리구에서 미생물 성장이 가장 저해된 것으로 나타났다. 가용성 고형분 함량, 적정산도 및 pH 등은 처리조건에 따른 큰 차이를 보이지 않았다. 따라서 ascorbic acid와 초음파의 병용 처리는 신선 절단 사과의 효소적 갈변을 억제하고, 미생물 성장을 저해하는 효과를 가지는 것으로 확인되었다.

• Journal of Microbiology and Biotechnology
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• 제21권4호
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• pp.341-346
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• 2011

To study the effects of salinity-sodicity on bacterial population and enzyme activities, soil samples were collected from the Bay of Yellow Sea, Incheon, South Korea. In the soils nearest to the coastline, pH, electrical conductivity ($EC_e$), sodium adsorption ratio (SAR), and exchangeable sodium percentage (ESP) were greater than the criteria of saline-sodic soil, and soils collected from sites 1.5-2 km away from the coastline were not substantially affected by the intrusion and spray of seawater. Halotolerant bacteria showed similar trends, whereas non-tolerant bacteria and enzymatic activities had opposite trends. Significant positive correlations were found between EC, exchangeable $Na^+$, and pH with SAR and ESP. In contrast, $EC_e$, SAR, ESP, and exchangeable $Na^+$ exhibited significant negative correlations with bacterial populations and enzyme activities. The results of this study indicate that the soil chemical variables related with salinity-sodicity are significantly related with the sampling distance from the coastline and are the key stress factors, which greatly affect microbial and biochemical properties.

• 환경위생공학
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• 제23권2호
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• pp.1-18
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• 2008

The tetrachloroethylene (PCE) dehalogenase of Clostridium bifermentans DPH-1 (a halorespiring organism) was purified, cloned, and sequenced. This enzyme is a homodimer with a molecular mass of ca. 70 kDa and exhibits dehalogenation of dichloroethylene isomers along with PCE and trichloroethylene (TCE). Broad range of substrate specificity for chlorinated aliphatic compounds (PCE, TCE, cis-1,2-dichloroethylene, trans-1,2-dichloroethylene, 1,1-dichloroethylene, 1,2-dichloropropene, and 1,1,2-trichloroethane) for this enzyme was also observed. A mixture of propyl iodide and titanium citrate caused a light-reversible inhibition of enzymatic activity suggesting the involvement of a corrinoid cofactor. A partial sequence (81 bp) of the encoding gene for PCE dehalogenase was amplified and sequenced with degenerateprimers designed from the N-terminal sequence (27 amino acid residues). Southern analysis of C. bifermentans genomic DNA using the polymerase chain reaction product as a probe revealed restriction fragment bands. A 5.0 kb ClaI fragment, harboring the relevant gene (designated pceC) was cloned (pDEHAL5) and the complete nucleotide sequence of pceC was determined. The gene showed homology mainly with microbial membrane proteins and no homology with any known dehalogenase, suggesting a distinct PCE dehalogenase. So, C. bifermentans could play some important role in the initial breakdown of PCE and other chlorinated aliphatic compounds in sites contaminated with mixtures of halogenated substances.

• Journal of Microbiology and Biotechnology
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• 제30권8호
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• pp.1244-1251
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• 2020

Phospholipase A₂ (PLA₂) from Streptomyces violaceoruber is a lipolytic enzyme used in a wide range of industrial applications including production of lysolecithins and enzymatic degumming of edible oils. We have therefore investigated expression and secretion of PLA₂ in two workhorse microbes, Pichia pastoris and Escherichia coli. The PLA₂ was produced to an activity of 0.517 ± 0.012 U/ml in the culture broth of the recombinant P. pastoris. On the other hand, recombinant E. coli BL21 star (DE3), overexpressing the authentic PLA₂ (P-PLA₂), showed activity of 17.0 ± 1.3 U/ml in the intracellular fraction and 21.7 ± 0.7 U/ml in the culture broth. The extracellular PLA2 activity obtained with the recombinant E. coli system was 3.2-fold higher than the corresponding value reached in a previous study, which employed recombinant E. coli BL21 (DE3) overexpressing codon-optimized PLA₂. Finally, we observed that the extracellular PLA₂ from the recombinant E. coli P-PLA₂ culture was able to hydrolyze 31.1 g/l of crude soybean lecithin, an industrial substrate, to a conversion yield of approximately 95%. The newly developed E. coli-based PLA₂ expression system led to extracellular production of PLA₂ to a productivity of 678 U/l·h, corresponding to 157-fold higher than that obtained with the P. pastoris-based system. This study will contribute to the extracellular production of a catalytically active PLA₂.