• Title/Summary/Keyword: Fad

Search Result 224, Processing Time 0.036 seconds

Production of (R)-(-)-mandelic acid by electrochemically driven enzyme bioreactor

  • Kim, Mi-Hae;Yun, Se-Eok
    • 한국생물공학회:학술대회논문집
    • /
    • 2001.11a
    • /
    • pp.642-645
    • /
    • 2001
  • Enterococcus faecalis was cultivated under oxidative conditions established by adding some oxidants. FAD and lipoic acid either stimulate the biosynthesis of benzoylformate reductase or stabilize the enzyme, while $MV^{2+}$ enhance the biosynthesis of the oxidoreductase but destabilize it. Since $MV^{2+}$ destabilize the benzoylformate reductase, substituting FAD for $MV^{2+}$ as a redox mediator would be desirable. Production of (R)-(-)-mandelic acid by a coupled reaction between the enzymatic reaction using benzoylformate reductase and the electrocatalytic reduction under the conditions of 1.5 U LiDH $ml^{-1}$, 0.2 mM FAD, and 0.3 mM $NAD^+$ is now performing.

  • PDF

BIOCHEMICAL STUDIES ON THE RIBOFLAVIN IN GREENBEANS DURING GERMINATION

  • Lee, Chul-Joon;Chung, Dong-Hyo
    • Applied Biological Chemistry
    • /
    • v.2
    • /
    • pp.29-35
    • /
    • 1961
  • The daily variation in the total quantity of flavin compounds (FAD, FMN, FR) in greenbean during its germination were measured by Yagi's methods. The results obtained were as follow. 1. The total quantity of flavin compounds of the greenbean sprouts was increased with growth of sprouts until the 8th days. After this period its contents were decreased slightly. 2. The flavin compounds of greenbean sprouts were comfirmed to be synthesized as free riboflavin during its germination. 3. FAD was the major pat of total flavin compounds in cotyledon but there was significant variation in the contents of FAD, FMN and FR in hypocotyl.

  • PDF

EFFECTS OF IONIZING RADIATION ON THE FORMATION OF RIBOFLAVIN IN SOYBEAN SPROUTS

  • Lee, C.Y.;Kim, H.T.;Shin, Y.S.;Choo, C.R.;Lee, K.Y.
    • Applied Biological Chemistry
    • /
    • v.1
    • /
    • pp.62-67
    • /
    • 1960
  • 1) The variations of flavin adenine dinucleotide(FAD), flavin monomucleotide(FMN) and free riboflavin in control and 600r X-ray irradiated soybean sprout were estimated by the paper chromatographic method. 2) It was found that the formation of riboflavin in soybean sprout was mainly in FAD. 3) There were no great variation of FMN and free riboflavin in soybean sprout during the germination. 4) The moderate amount (600r) of X-ray irradiation accerelated the formation of FAD in soybean sprout during the germination.

  • PDF

Studies on the Development of Photoreceptor in the Nonchromatophore Organisms (V) - Effects of FAD and $FADH_2$ on Light-Induced Mitochondrial ATPase and ATP Synthase in Lentinus edodes - (무흡광색소 생물의 감광수용체 개발연구(V) - 표고버섯 중의 광감응성 Mitochondrial ATPase 및 ATP synthase에 대한 FAD 및 $FADH_2$의 효과 -)

  • Park, Sang-Shin;Min, Tae-Jin
    • The Korean Journal of Mycology
    • /
    • v.17 no.3
    • /
    • pp.161-168
    • /
    • 1989
  • Mitochondria in L. edodes were separated and purified by stepped sucrose density gradient centrifugation. In our previous work, we have found that the activation wavelengths of the mitochondrial ATPase and ATP synthase were 680 nm and 470 nm within the range of 400-700 nm, respectively. The activities of the above enzymes with wavelengths of 300-400 nm region were investigated. The mitochondrial ATPase and ATP synthase were stimulated at 380 nm and 330 nm, respectively, for 30 min illumination compared with dark control group. They, however, were inhibited at 330 nm and 350 nm, respectively. The presence of FAD resulted in inhibition of the activity of the ATPase and stimulation of the activity of the ATP synthase by the activation and inhibition wavelengths. However, the activities of these enzymes were not changed by NADH for the above wavelengths. In the spectral properties, the oxidation of $FADH_2$ into FAD occurs in the presence of the enzymes for illumination of the activation and inhibition wavelengths. Therefore, we can predict that the mitochondrial ATPase and ATP synthase may function as oxidant in the redox reaction by the light illumination and that the light-induced pigment of the mitochondrial ATP synthase should be an oxidized form of a flavoprotein.

  • PDF

Is TQM a Dying Fad? (TQM의 시대는 지나가고 있는가?)

  • Park Young-Taek;Roh Jae-Heon
    • Proceedings of the Korean Society for Quality Management Conference
    • /
    • 1998.11a
    • /
    • pp.659-664
    • /
    • 1998
  • Even though advocates of TQM emphasize the role of TQM more than before, the interest of general public have decreased in recent years. A few months ago, the Fortune introduced a survey result showing that management tools (including TQM) are to some extent fashion items, becoming chic or declasse with the march of the management zeitgeist. According to the article, TQM has cooled off and other approaches have risen to take the place. Is TQM a really dying fad? This paper discusses the problem.

  • PDF

Influence of Food Dye on the Activity of Hepatic Azo Reductase and the Effect of Flavin (식용 Azo 색소가 Hepatic Azo Reductase에 미치는 영향과 Flavin의 효과)

  • 윤혜정;원형란
    • Journal of Food Hygiene and Safety
    • /
    • v.2 no.1
    • /
    • pp.9-14
    • /
    • 1987
  • With the market of food products, the use of food additives is on the increase. The dye as food additives, can be used for some foods which are difficult to preserve their own colors. It can be also classified as tar dye, vegetable dye and mineral dye. Because tar dye has dense toxicity, only 15 articles among them are legally allowed to be used. Among the allowed articles, the azo compound amaranth, tartrazine, sunset yellow, and allura red, were used in determining and comparing rat hepatic azo reductase activity and we observed the flavin's effects as follows: 1. Investigation with amaranth as substrate gave an apparent Km of $645\;\mu\textrm{M}$ and Vmax of 50 n mol/min/mg protein. 2. On investigation using a fixed amaranth concentration over a range of flavin concentration, FAD significantly increased the activity of the azo reductase compared with only minor increases in reaction mediated by the NADPH-generating system alone. 3. On investigation with amaranth, tartrazine, sunset yellow allura red as electron acceptor in the absence or presence of 300 mM-FAD, sunset yellow was reduced at a rat similar to amaranth, tartrazine was reduced at a slower rate and allura red was reduced a little more rapidly.

  • PDF

Analysis on the fishing conditions of tuna purse seiner belonging to the Korea-Ghana joint venture in the Atlantic Ocean (대서양 한-가나 합작법인 소속 다랑어 선망어선의 조업실태 분석)

  • KWON, Ki-Jun;LEE, Chun-Woo;KIM, Hyung-seok;RYU, Kyung-Jin;LEE, Yoo-Won
    • Journal of the Korean Society of Fisheries and Ocean Technology
    • /
    • v.57 no.3
    • /
    • pp.194-204
    • /
    • 2021
  • The research was analyzed the catch data of the five years (2016-2020) for six joint venture company tuna purse seiners in the Atlantic Ocean, with the aim of suggesting improvement measures for responsible and sustainable fishing according to changes of recommendation by International Commission for the Conservation of Atlantic Tuna (ICCAT) on the tropical tunas. In the last five years, the average catch of six tuna purse seiner gradually increased to 7,745 tons, 8,364 tons and 9,053 tons from 2016 to 2018, but decreased to 7,761 tons in 2019 and 6,214 tons in 2020. The reason for the decrease in fishing volume in 2019 and 2020 was the fluctuation of the formation of the cold water zone (22-23℃), and the total ICCAT convention area of FAD closure in January and February due to the expansion of the FAD closure area and poor free school catching during two months period, respectively. The analysis on fishing area showed that the percentage of fishing in the high sea was about 85% although the FAD closure area included the EEZ zone in coastal countries; the rise of the fishing license in coastal countries is also believed to be a factor. In order to overcome such situations and improve catching volume, it will be possible if excellent manpower is secured, school fishing is expanded, and the production of high value-added catch (purse seine special: PS).

Characterization of the Catalytic Properties of Recombinant Acetohydroxyacid Synthase from Tobacco

  • Kim, Joung-Mok;Choi, Jung-Do;Kim, Bok-Hwan;Yoon, Moon-Young
    • Bulletin of the Korean Chemical Society
    • /
    • v.26 no.2
    • /
    • pp.260-264
    • /
    • 2005
  • The nature of the active site of Tobacco acetohydroxyacid synthase (AHAS) in the substrate- and cofactorbinding was studied by kinetics and fluorescence spectroscopy. The substrate saturation curve does not follow Michaelis-Menten kinetics at different temperatures (7, 21 and 37 ${^{\circ}C}$), pH (6.5, 7.5 and 8.5) and buffers (Tris-HCl and MOPS). The concentration of one half of the maximum velocity ($S_{0.5}$) decreased in the following order: pyruvate $\gt$ ThDP $\approx$$Mg^{+2}$ $\gt$ FAD. However, the catalytic efficiency (K$_{cat}/S_{0.5}$) inversely decreased in the following order; FAD $\gt$ $Mg^{+2}$ $\approx$ThDP $\gt$ pyruvate, indicating that the cofactors by in decreasing order; FAD, $Mg^{+2}$, ThDP, affect the catalysis of AHAS. The dissociation constant ($K_d$) of the intrinsic tryptophan fluorescence decreased with the same tendency of the concentration of one half of the maximum velocity ($S_{0.5}$) decreasing order. This data provides evidence that the substrate and cofactor binding natures of the active site, as well as its activation characteristics, resemble those of other ThDP-dependent enzymes.