• 제목/요약/키워드: pH dependent

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효모의 미토콘드리아와 M-DNA (On the Mitochmria of Yeast and M-DNA)

  • 홍순우
    • 미생물학회지
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    • 제9권1호
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    • pp.39-45
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    • 1971
  • saccharomyces cerevisiae J170, mutant를 사용하여 YEP 배지에서 20시간 진탕 배양하여 생장이 왕성한 영양시기의 효모세포를 얻었다. 이 세포를 sporulation medium에 접종하여 3$0^{\circ}C$에서 20시간 진탕 배양하면 약 80%의 ascospore를 형성함을 볼 수 있었다. 포자형성시기와 생장시기를 택하여 D-C-glucose 운반에 관하여 비교 검토한 결과는 다음과 같다. haploid인 포자형성시나 diploid인 생장시기의 포도당 흡수는 PH6.0에서 최대이었다. 이 두 시기는 포도당 운반은 2,4-dinitrophenol에 의하여 저해되었으므로 포자형성기의 포도당운반도 역시 energy를 요구하는 능동수송과 연관이 있음을 알게 되었아. 생장시기의 포도당 흡수정도는 포자형성기 보다 높았으며 이때에 fructose나 galactose와 포도당흡수의 관계는 서로 경쟁적으로 작용함을 알 수 있었다. 효모세포의 당 성분은 ribose, mannose, $\alpha$,$eta$-glucose로 되어 있으며 특히 포자형성기의 mannose 함량은 영양세포 때보다 현저히 적었다.

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호두 첨가가 양조간장의 지방산 조성에 미치는 영향 (Effects of Addition of Walnuts on Fatty Acid Composition of Soy Sauce)

  • 최희은;유범석;최호민;김준협;정성모;이난희;김나율;최웅규
    • 한국식품영양학회지
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    • 제30권5호
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    • pp.860-866
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    • 2017
  • This study was conducted to assess effects of addition of walnuts on soy sauce quality. The pH was significantly increased by adding more than 4 percent of walnuts. As the addition of walnuts increased, Hunter's color values and brown color increased. Total solid of soy sauce did not change significantly with the addition of walnuts. Crude fat content increased by two times in the 2 percent added walnuts group compared to the control group, but it was not dependent on the addition of walnuts. DPPH radical scavenging activity was significantly increased with the addition of walnuts. The addition of walnuts decrease saturated fatty acids and increased unsaturated fatty acids. Composition ratio of linoleic acid was highest in the control group and all the additions. These results revealed that soy sauce made with walnuts have a positive effect on functionality and preference.

DNA 사슬 종결형 항암제인 플루다라빈에 의해 유도된 세포독성에 대한 아로니아-홍삼 에탄올 혼합 추출물의 효과 (Effects of Aronia melanocarpa and Korean Red Ginseng Ethanol Extracts Combination on Cytotoxicity induced by Fludarabine, a DNA Chain Terminating Anti-Cancer Drug)

  • 김민섭;정유헌;오홍근;박종군
    • 한국식품영양학회지
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    • 제30권4호
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    • pp.673-680
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    • 2017
  • Fludarabine, a chain terminating anti-cancer drug, is a purine analogue that causes DNA strand breaks in normal cells. In this study, we determined if A. melanocarpa and Korean red ginseng extract mixture reduce cytotoxicity of fludarabine. Treatment of HaCaT cells with $10{\mu}M$ of fludarabine for 24 hours decreased cell viability and increased DNA strand breaks. Treatment of A. melanocarpa and Korean red ginseng extract mixture for 24 hours increased cell viability as compared with single extract treatment. The protective effect of these extracts on cell activity increased in a concentration-dependent manner. DNA strand breaks induced by fludarabine decreased as concentration of extract mixture increased. p-H2AX level, a marker of DNA strand breakage, decreased depending on the concentration of extract mixture. The effect of mixed extract of A. melanocarpa and Korean red ginseng on DNA damage is due to the anti-oxidative effect of A. melanocarpa and signal transmission through glucocorticoid receptor upon binding of saponin of Korean red ginseng.

잔류 불산에 의한 모델 지질토양시료의 광물 용해 및 비소 용출 특성 (Impact of Residual Hydrofluoric Acid on Leaching of Minerals and Arsenic from Different Types of Geological Media)

  • 전필용;문희선;신도연;현성필
    • 한국지하수토양환경학회지:지하수토양환경
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    • 제23권2호
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    • pp.23-29
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    • 2018
  • This study explored secondary effects of the residual hydrofluoric acid (HF) after a hypothetical acid spill accident by investigating the long-term dissolution of minerals and leaching of pre-existing arsenic (As) from two soil samples (i.e., KBS and KBM) through batch and column experiments. An increase in the HF concentration in both soil samples resulted in a dramatic increase in the release of major cations, especially Si. However, the amounts of mineral dissolved were dependent on the soil type and mineral characteristics. Compared to the KBM soil, relatively more Ca, Mg and Si were dissolved from the KBS soil. The column experiment showed that the long-term dissolution rates of the minerals are closely associated with the acid buffering capacity of the two soils. The KBM soil had relatively higher effluent pH values compared to the KBS soil. Also, more As was leached from the KBM soil, with a more amorphous hydrous oxide-bound As fraction. These results suggest that the potential of heavy metal leaching by the residual acid after an acid spill will be influenced by heavy metal speciation and mineral structure in the affected soil.

Heteroexpression and Functional Characterization of Glucose 6-Phosphate Dehydrogenase from Industrial Aspergillus oryzae

  • Guo, Hongwei;Han, Jinyao;Wu, Jingjing;Chen, Hongwen
    • Journal of Microbiology and Biotechnology
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    • 제29권4호
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    • pp.577-586
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    • 2019
  • The engineered Aspergillus oryzae has a high NADPH demand for xylose utilization and overproduction of target metabolites. Glucose-6-phosphate dehydrogenase (G6PDH, E.C. 1.1.1.49) is one of two key enzymes in the oxidative part of the pentose phosphate pathway, and is also the main enzyme involved in NADPH regeneration. The open reading frame and cDNA of the putative A. oryzae G6PDH (AoG6PDH) were obtained, followed by heterogeneous expression in Escherichia coli and purification as a his6-tagged protein. The purified protein was characterized to be in possession of G6PDH activity with a molecular mass of 118.0 kDa. The enzyme displayed maximal activity at pH 7.5 and the optimal temperature was $50^{\circ}C$. This enzyme also had a half-life of 33.3 min at $40^{\circ}C$. Kinetics assay showed that AoG6PDH was strictly dependent on $NADP^+$ ($K_m=6.3{\mu}M$, $k_{cat}=1000.0s^{-1}$, $k_{cat}/K_m=158.7s^{-1}{\cdot}{\mu}M^{-1}$) as cofactor. The $K_m$ and $k_{cat}/K_m$ values of glucose-6-phosphate were $109.7s^{-1}{\cdot}{\mu}M^{-1}$ and $9.1s^{-1}{\cdot}{\mu}M^{-1}$ respectively. Initial velocity and product inhibition analyses indicated the catalytic reaction followed a two-substrate, steady-state, ordered BiBi mechanism, where $NADP^+$ was the first substrate bound to the enzyme and NADPH was the second product released from the catalytic complex. The established kinetic model could be applied in further regulation of the pentose phosphate pathway and NADPH regeneration of A. oryzae to improve its xylose utilization and yields of valued metabolites.

Far-infrared radiation stimulates platelet-derived growth factor mediated skeletal muscle cell migration through extracellular matrix-integrin signaling

  • Lee, Donghee;Seo, Yelim;Kim, Young-Won;Kim, Seongtae;Bae, Hyemi;Choi, Jeongyoon;Lim, Inja;Bang, Hyoweon;Kim, Jung-Ha;Ko, Jae-Hong
    • The Korean Journal of Physiology and Pharmacology
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    • 제23권2호
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    • pp.141-150
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    • 2019
  • Despite increased evidence of bio-activity following far-infrared (FIR) radiation, susceptibility of cell signaling to FIR radiation-induced homeostasis is poorly understood. To observe the effects of FIR radiation, FIR-radiated materials-coated fabric was put on experimental rats or applied to L6 cells, and microarray analysis, quantitative real-time polymerase chain reaction, and wound healing assays were performed. Microarray analysis revealed that messenger RNA expressions of rat muscle were stimulated by FIR radiation in a dose-dependent manner in amount of 10% and 30% materials-coated. In 30% group, 1,473 differentially expressed genes were identified (fold change [FC] > 1.5), and 218 genes were significantly regulated (FC > 1.5 and p < 0.05). Microarray analysis showed that extracellular matrix (ECM)-receptor interaction, focal adhesion, and cell migration-related pathways were significantly stimulated in rat muscle. ECM and platelet-derived growth factor (PDGF)-mediated cell migration-related genes were increased. And, results showed that the relative gene expression of actin beta was increased. FIR radiation also stimulated actin subunit and actin-related genes. We observed that wound healing was certainly promoted by FIR radiation over 48 h in L6 cells. Therefore, we suggest that FIR radiation can penetrate the body and stimulate PDGF-mediated cell migration through ECM-integrin signaling in rats.

Electrochemical Characteristics of Water-Soluble Phosphate-Functionalized Naphthalene- and Perylene-Bisimides and Their Zirconium Bisphosphate Multilayers on ITO Electrode

  • Cho, Kwang Je;Kim, Yeong Il;Shim, Hyun Kwan
    • 대한화학회지
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    • 제63권1호
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    • pp.37-44
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    • 2019
  • N,N'-bis(ethyldihydrogen phosphate)-1,4,5,8-naphthalene bis(dicarboximide) (EPNI) and N,N'-bis(ethyldihydrogen phosphate)-3,4,9,10-perylene bis(dicarboximide) (EPPI) and their zirconium bisphosphate multilayers (Zr-EPNI and Zr-EPPI), that had been briefly reported by us, were further investigated in terms of their electrochemical properties. EPNI in aqueous solution showed typical two reversible reductions at ITO electrode but the reductions were strongly dependent on solution pH while EPPI showed only an irreversible reduction. The single and mixed multilayers of Zr-EPNI and Zr-EPPI were well constructed on ITO electrode by the alternate adsorptions of zirconium ion and the bisimides. While Zr-EPNI multilayer on ITO electrode showed single broad reversible reduction with $E_{1/2}=-0.68V$, Zr-EPPI gave two separated reductions at $E_{1/2}=-0.54$ and -0.81 V vs SCE, quite differently from the solution properties. The average layer densities of the multilayers were estimated as $1.5{\times}10^{-10}$ and $2.3{\times}10^{-10}mol/cm^2$ for Zr-EPNI and Zr-EPPI, respectively. Both the monolayers of Zr-EPNI and Zr-EPPI could not completely block the electron transfer between $Fe(CN){_6}^{3-}$ in solution and ITO electrode but 3-5 layers of Zr-EPNI and Zr-EPPI could block it completely and mediated the one-way electron transfer at the potential shifted to their reduction potentials. When the monolayer of zirconium 1,10-decanediylbisphosphonate (Zr-DBP) was used as a sublayer of Zr-EPNI and Zr-EPPI layers, the mediated electron transfer became prominent without any direct electron transfer.

Genetic overgrowth syndrome: A single center's experience

  • Cheon, Chong Kun;Kim, Yoo-Mi;Yoon, Ju Young;Kim, Young A
    • Journal of Genetic Medicine
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    • 제15권2호
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    • pp.64-71
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    • 2018
  • Purpose: Overgrowth syndromes are conditions that involve generalized or localized areas of excess growth. In this study, the clinical, molecular, and genetic characteristics of Korean patients with overgrowth syndrome were analyzed. Materials and Methods: We recruited 13 patients who presented with overgrowth syndrome. All patients fulfilled inclusion criteria of overgrowth syndrome. Analysis of the clinical and molecular investigations of patients with overgrowth syndrome was performed retrospectively. Results: Among the 13 patients with overgrowth syndrome, 9 patients (69.2%) were found to have molecular and genetic causes. Among the seven patients with Sotos syndrome (SS), two had a 5q35microdeletion that was confirmed by fluorescent in situ hybridization. In two patients with SS, intragenic mutations including a novel mutation, c.5993T>A (p.M1998L), were found by Sanger sequencing. One patient had one copy deletion of NDS1 gene which was confirmed by multiplex ligation-dependent probe amplification. Among five patients with Beckwith-Wiedemann syndrome, three had aberrant imprinting control regions; 2 hypermethylation of the differentially methylated region of H19, 1 hypomethylation of the differentially methylated region of Kv. In one patient displaying overlapping clinical features of SS, a de novo heterozygous deletion in the chromosomal region 7q22.1-22.3 was found by single nucleotide polymorphism-based microarray. Conclusion: Considering high detection rate of molecular and genetic abnormalities in this study, rigorous investigations of overgrowth syndrome may be an important tool for the early diagnosis and genetic counseling. A detailed molecular analysis of the rearranged regions may supply the clues for the identification of genes involved in growth regulation.

The Effect of Vinegar Fermentation on the Nutritional Quality of Lotus Flower Fermented Product

  • Nam, Mikyung;Chrysta, Maynanda Brigita;Lee, Eunsuk;Choi, Wonsik
    • 한국산업융합학회 논문집
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    • 제22권1호
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    • pp.61-69
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    • 2019
  • All the parts of lotus, including the seed, rhizome, leaf, stalk, petal, anther, pericarp, and fruit receptacle, have been used in traditional medicine system as a health beneficial supplement. However the most usually used from lotus plant is only the root. Therefore in this study, it will be discussed more the utilization of other parts of the lotus, namely the flower of lotus. The petals and stamens of lotus actually are also rich in bioactive components such as flavonoids and alkaloids, are used in the treatment of tissue inflammation, cancer, skin disease, and also for us as antidotes. One of the biotechnological process that can be used to improve the nutritional content, sensory, and also antioxidant activities is fermentation process. The final product desired from the fermentation process in this study is vinegar. The microbial strain powder used is Uinkin fermented powder with three variations of fermentation. The variations given in this study were initial sugar 32%, 24%, and 14% with the same fermentation temperature, $35^{\circ}C$ for 3 months. The results obtained showed that the pH value and sugar content of products during the fermentation process were decreasing during the fermentation process, with total polyphenol content of $283.7{\pm}97.6mg/100g\;QAE$, and total flavonoid content of $3.3{\pm}0.0mg/100g\;QAE$. For the DPPH radical scavenging ability of the fermentation product also increased in a concentration dependent manner, with ORAC activity of the product showed a high activity of $20.7{\pm}0.41{\mu}M$ TE. Therefore, fermentation process can be the one of method for improving the product. The efficiency of lotus flower vinegar fermentation can be reached with an initial sugar condition of 25% (sample B).

LPS로 유도된 RAW 264.7 세포에서 지칭개 추출물의 항염 효과 (Anti-inflammatory effect of Hemistepta lyrata Bunge (Bunge) on LPS-induced inflammation in RAW 264.7 cells)

  • 김재광;박수영;최화영;장미희;정대화;김상찬;조일제
    • 대한한의학방제학회지
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    • 제27권1호
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    • pp.7-16
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    • 2019
  • Objectives : Hemistepta lyrata Bunge (Bunge) has been used for treating wound, hemorrhage, fever in Korean traditional medicine. Present study investigated anti-inflammatory effect of H. lyrata chloroform extract (HLE) and its molecular mechanism involved. Methods : To assess anti-inflammatory effect of HLE, production of nitric oxide (NO) and expressions of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and pro-inflammatory cytokines were measured on lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. Moreover, nuclear factor-${\kappa}B$ (NF-${\kappa}B$) signaling pathway was examined to elucidate its molecular mechanism. Results : Pretreatment of HLE inhibited NO production in a concentration dependent manner. HLE also decreased expression of iNOS and COX-2, and alleviated expressions of pro-inflammatory cytokines in LPS-stimulated RAW 264.7 cells. Moreover, HLE pretreatment inhibited phosphorylation of inhibitory-${\kappa}B{\alpha}$ and p65. Conclusions : These results suggest that HLE exhibits anti-inflammatory effect via inhibition of NF-${\kappa}B$.