• Title/Summary/Keyword: -cyclodextrin

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Evaluation of the Diversity of Cyclodextrin-Producing Paenibacillus graminis Strains Isolated from Roots and Rhizospheres of Different Plants by Molecular Methods

  • Vollu Renata Estebanez;Fogel Rafael;Santos Silvia Cristina Cunha dos;Mota Fabio Faria da;Seldin Lucy
    • Journal of Microbiology
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    • v.44 no.6
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    • pp.591-599
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    • 2006
  • To address the diversity of cyclodextrin-producing P. graminis strains isolated from wheat roots and rhizospheres of maize and sorghum sown in Australia, Brazil, and France, restriction fragment length polymorphism analysis of part of genes encoding RNA polymerase (rpoB-RFLP) and DNA gyrase subunit B (gyrB-RFLP) was used to produce genetic fingerprints. A phylogenetic tree based on rpoB gene sequences was also constructed. The isolates originated from Brazil could be separated from those from Australia and France, when data from the rpoB-based phylogenetic tree or gyrB-RFLP were considered. These analyses also allowed the separation of all P. graminis strains studied here into four clusters; one group formed by the strains GJK201 and $RSA19^T$, second group formed by the strains MC22.02 and MC04.21, third group formed by the strains TOD61, TOD 221, TOD302, and TOD111, and forth group formed by all strains isolated from plants sown in Cerrado soil, Brazil. As this last group was formed by strains isolated from sorghum and maize sown in the same soil (Cerrado) in Brazil, our results suggest that the diversity of these P. graminis strains is more affected by the soil type than the plant from where they have been isolated.

Fed-batch Fermentations of Recombinant Escherichia coli to Produce Bacillus macerans CGTase

  • Park, Yong-Cheol;Kim, Chang-Sup;Kim, Chung-Im;Choi, Kyu-Hwan;Seo, Jin-Ho
    • Journal of Microbiology and Biotechnology
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    • v.7 no.5
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    • pp.323-328
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    • 1997
  • The recombinant Escherichia coli BL21(DE3)pLysE : pTCGT1 was grown to overproduce Bacillus macerans cyclodextrin glucanotransferase (CGTase) able to synthesize ${\alpha}$-cyclodextrin (CD) with a selectivity of 67%. A number of batch fermentations were performed to test the possibility of using lactose as an inducer of the E. coli T7 promoter system. A mixture of isopropyl ${\beta}$-D-thiogalactoside (IPTG) and lactose (1 : 1) gave a maximum CGTase activity of 2.4 U/ml, which was higher than the value obtained with induction by IPTG alone. Fed-batch fermentations involving a glucose-controlled growth period followed by a gene-expression phase with mixtures of IPTG and lactose were employed to achieve high cell density and thereby increase total CGTase activity. Optimized fed-batch fermentation using the modified inducer (IPTG : lactose=1 : 3) and 100 g/l yeast extract solution in the gene-expression phase resulted in a maximum CGTase activity of 62.9 U/ml and a final cell mass of 53.5 g/l, corresponding to a 31-fold increase in CGTase activity and a 29-fold increase in cell mass compared with the control batch fermentation.

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Chemical Sensors Using Polymer/Graphene Composite and The Effect of Graphene Content on Sensor Behavior (고분자/그래핀 복합재료의 센서 응용 및 그래핀 함량이 센서 거동에 미치는 영향)

  • Bae, Joonwon
    • Applied Chemistry for Engineering
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    • v.31 no.1
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    • pp.25-29
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    • 2020
  • In this study, a polymer/graphene hybrid composite was prepared by a simple roll-method and a simple sensor was produced by a convenient surface engineering procedure. The sensor performance was examined and the effect of graphene content on the sensing behavior was monitored. A polymer (polydimethylsiloxane, PDMS) paste containing graphene powder was prepared by a three-roll apparatus and polymer/graphene hybrid composite was produced by a two-roll technique. The sensing medium, cyclodextrin (CD) was introduced by a convenient bio-conjugation method. The efficacy of surface modification was confirmed by FT-IR spectroscopy and the ohmic relation was observed on composite surfaces. An analyte (e.g., methyl paraben, MePRB) at a 10 nM concnetration could be detected. When the graphene loading was low, the sensor performance was relatively poor. This was attributed to the absence of graphene alignments, which were observed for the composites having a high graphene loading. This indicates that the sensor performance was influenced by physical alignments of the filler. This article can provide important information for future research on developing sensing devices.

Effects of Selected Stabilizers on the Color Deterioration of Crude Pigment Extract from Schizandra fruit (Schizandra Fructus) (여러 가지 안정화 물질이 오미자 색소 추출물의 가열 변색에 미치는 영향)

  • Kim, Hyun-Jung;Cho, Sung-Bin;Chun, Hyang-Sook
    • Journal of the Korean Society of Food Culture
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    • v.18 no.5
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    • pp.475-482
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    • 2003
  • The effects of selected stabilizers and sugars on color deterioration of anthocyanin in Schizandra fructus were examined at $100^{\circ}C$ for $120{\sim}180$ min. Among four test sugars, it was found that fructose accelerated the thermal color deterioration while maltose retarded the color deterioration by 40%. Maltodextrin and ${\gamma}$-cyclodextrin showed the highest stabilizing effect on the thermal color deterioration of crude pigment extract from Schizandra fructus(CPES) containing 2 mg% of anthocyanin. Addition of maltodextrin or ${\gamma}$-cyclodextin at 5% retarded thermal color deterioration of CPES. In gel system, 5% of maltodextrin also retarded the color deterioration by $15{\sim}20%$ during storage at $25^{\circ}C\;and\;35^{\circ}C$.

Effect of Cholesterol and Serum Albumin on Sperm Ability and Lipid Peroxidation during the Storage of Miniature Pig Sperm (미니돼지정액의 보존 시 콜레스테롤과 혈청 알부민이 정자 성상과 지질 과산화에 미치는 영향)

  • Kim, Dong-Woo;Lee, Yong-Seung;Yoo, Han-Jun;Cheong, Hee-Tae;Yang, Boo-Keun;Park, Choon-Keun
    • Journal of Embryo Transfer
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    • v.26 no.1
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    • pp.71-78
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    • 2011
  • This study was undertaken to find out the effect of cholesterol and serum albumin on sperm ability and lipid peroxidation levels period to the liquid storage of miniature pig sperm. Ejaculated semen from miniature pigs was collected by gloved-hand method into a pre-warmed ($37^{\circ}C$) thermos bottle, and extended with Modena solution {with and without BSA, methyl-beta-cyclodextrin (-cholesterol) and cholesterol loaded cyclodextrin (+cholesterol)}. Each semen was assessed for viability (SYBR-14/PI staining) and acrosome intactness, intensity and capacitation status by chlorotetracycline (CTC) staining at 1, 3, 5, 7 and 10 days of storage. At for the effects of cholesterol and serum albumin on lipid peroxidation, semen were incubated with $H_2O_2$ ($10\;{\mu}M$), and lipid peroxidation level were measured by flow cytometry using the lipid peroxidation reporter probe $C_{11}-BODIPY^{581/591}$. The result, lipid peroxidation level in sperm added with cholesterol were lower in $10\;{\mu}M$ $H_2O_2$ compared to the added sperm with serum albumin. Also, added cholesterol to sperm had significant (p<0.05) higher viability when storage for 7 and 10 days and lower when 10 days of storage percentage of acrosome-reacted sperm (AR pattern) in acrosome state as say result compared to other treated groups. In conclusion, role of cholesterol during lipid storage in miniature pig spermatozoa was protected boar spermatozoa from lipid peroxidation prior to lipid storage. Addition serum albumin during lipid storage in sperm may be induce sperm membrane damage by lipid peroxidation. Therefore, addition of cholesterol to miniature pig sperm will be lead to extension of liquid storage periods.