• Applied Biological Chemistry
• /
• v.36 no.5
• /
• pp.364-369
• /
• 1993

Triton X-100 enhances to a marked extent the analytical sensitivity of the nitrobluetetrazolium (NBT) reduction method for the assay of superoxide$(O^-_{\.{^.2}})$ production. In the present work, it was attempted to elucidate the physicochemical nature of this Triton X-100 effect, focusing on not only the surfactant-caused stabilization of the water-insoluble formazan colloid but also the kinetic competition between the $NBT-O^-_{\.{^.2}}$ reaction and the autodisproportionation of concommitantly occuring in aqueous media. The measurements of formazan and $H_2O_2$ formed in a number of reaction systems, as prepared by vortex-mixing potassium superoxide dissolved in an aprotic solvent with aqueous solutions of NBT, revealed that Triton X-100 exerts its effect both through preventing formazan colloid from aggregation and thereby increasing the formazan absorbance and through suppressing the autodisproportionation reaction of $O^-_{\.{^.2}}$. It also turned out that the relative shares of the colloid stabilization effect and the kinetic effect in the contribution to the sensitivity amplification of the NBT method are dependent upon the reaction conditions, particulary the molar concentration ratio of NBT to $O^-_{\.{^.2}}$ in the reaction systems.

• Korean Journal of Pharmacognosy
• /
• v.28 no.4
• /
• pp.225-232
• /
• 1997

300 extracts derived from 100 plants were tested for their potential to induce HL-60 cell differentiation using NBT assay and NSE/SE staining methods. Morphological changes from suspended to adherent state of the cells were also observed by microscopic examination. In result, 55 extracts induced cell differentiation into monocyte/macrophage lineage in the NBT and the NSE assay.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2004.07b
• /
• pp.894-897
• /
• 2004

Sodum bismuth titanate $(Na_{0.5}Bi_{0.5}TiO_3$ or NBT) thin films coated on the $LaNiO_3$ (LNO) electrode by sol-gel methode and rapid thermal annealing (RTA) technique. The NBT (NBT/LNO/Si) thin films examined by x-ray diffraction (XRD). The orientation of NBT was observed for films coated at $900^{\circ}C$, 5 min and $600^{\circ}C$, 60 min. Filed emission scanning electron microscopy (FE-SEM) showed uniform surface composed of grains. The grain size of NBT thin films increased with increasing annealing temperature.

• Journal of the Korean Wood Science and Technology
• /
• v.35 no.6
• /
• pp.126-134
• /
• 2007

This study reviewed the application of an extract from Kalopanax pictus stem bark and root bark as natural antioxidants. To investigate the effect on cell toxic level against transformed mouse fibroblast L929 in formula added with various extracts from Kalopanax pictus stem bark and root bark, this experiment was carried out by in vitro cytotoxicity method. Using DCFA-DA method, oxidative stress in cell was measured with other antioxidant activity methods including DPPH assay and NBT assay. Active oxygen inhibition rate for root bark insoluble hot water extracts showed the highest with 57.9% for 15 min treatment. In DPPH and NBT test, antioxidant activities of methanol extract from stem bark and insoluble hot water extract from stem bark were 96% (at 0.1%) and 95% (at 0.5%), respectively.

• Journal of Ginseng Research
• /
• v.11 no.1
• /
• pp.24-31
• /
• 1987

We studied a assay method on the measurement of superoxide dismutase (SOD Superoxide : superoxide oxidoreductase, EC. 1. 15. 1. 1) activity with photoreduced flavin and nitroblue tetrazolium (NBT) as superoxide (${O_2}^{-}$) source and detector, respectively. The $\Delta$E (1000 ng SOD$.$$min.)^{-1}$ of photoreduced flavin-NBT system was 0.08, whereas that of xanthine-xanthine-cytochrome system used broadly in experiments was 0.014. Therefore, the new method was regarded more simple and utilizable than xanthine-xanthine cytochrome system method. In the present paper, we also carried out to investigate the SOD activity and isozyme pattern for the parpose of study of leaf-burning disease in ginseng (Panax ginseng C.A. Meyer) leaves.

• The Journal of Internal Korean Medicine
• /
• v.25 no.1
• /
• pp.106-118
• /
• 2004

Antigenotoxicity test (SOS chromotest), antimutagenecity test (Ames test), and antioxidant test (NBT method and xanthine-xanthine oxidase method) were carried out using water-soluble and methanolic extracts from Puerariae Flos. Against the mutagens MNNG and NQO, antigenotoxic activity of methanolic extracts were much more effective than that of water-soluble ones. When the methanolic extract was added to the certain concentration $(100{\mu}{\ell}/tube)$, antigenotoxic acivity against the mutagen MNNG was enhanced. Contrary to the water-soluble extract, the methanolic extract showed high antigenotoxicity against the mutagen NQO with increment of the extract. Against the mutagen MNNG with Ames test, antimutagenic activity of the methanolic extract at $300{\mu}{\ell}/tube$ was 96% as an inhibition ratio of revertant forming CFU/plate. The antioxidant activity of water-soluble extract was comparatively higher than that of the methanolic one.

• Korean Journal of Materials Research
• /
• v.31 no.11
• /
• pp.649-656
• /
• 2021

K_0.5Bi_0.5TiO₃ (KBT) thin films were prepared by sol-gel processing for future use in piezoelectric generators. It is believed that the annealing temperature of films plays an important role in the output performance of piezoelectric generators. KBT films prepared on Ni substrates were annealed at 500 ~ 700 ℃. Tetragonal KBT films were formed after annealing process. As the annealing temperature increased, the grain size of KBT films increased. KBT thin films show piezoelectric constant (d₃₃) from 23 to 41 pC/N. The increase of grain size in KBT films brought about output voltage and current in the KBT generators. Also, the increase in the displacement of specimens during bending test resulted in increases in output voltage and current. Although KBT generators showed lower output power than those of generators prepared using NBT films, as reported previously, the KBT films prepared by sol-gel method show applicability as piezoelectric thin films for lead-free nano-generators, along with NBT films.

• Journal of fish pathology
• /
• v.14 no.1
• /
• pp.3-10
• /
• 2001

The present study was to obtain a basic research data about medicinal herbs by screening in vitro antimicrobial activity and the production of superoxide anion($O_2^-$) from the head kidney phagocytes of olive flounder, Paralichthys olivaceus. The following fourteen kinds of medicinal herbs extracted by boiling water were used : Gosam, Gwijeonu, Gujeolcho, Bagha, Bangpung, Yeongyo, Yagssug, Jiyu, Sambaegcho, Samjiguyeobcho, Sangbaegpi, Sohwehyang, Pyeonchug, Palgag. Antimicrobial activity against fish pathogenic bacteria, Listonella anguillarum, Vibrio sp., Vibrio alginolyticus, Edwardsiella tarda, Streptococcus sp. and Lactococcus garvieae, and the production of superoxide in kidney macrophage of olive flounder were examined by disk method and nitroblue tetrazolium(NBT) reaction, respectively. Among the tested herbs, Yagssug showed the highest antimicrobial activity against those fish pathogenic bacteria and stimulation of $O_2^-$ production.

• Journal of Chest Surgery
• /
• v.33 no.2
• /
• pp.117-124
• /
• 2000

Background: Nucleoside transport inhibitor(NTI) Keeps AMP, ADP, ATP levels high in myocytes by inhibiting adenosine cataboilsm so that it may preserve the myocardial contractability during ischemia In this study we investigated the effects of cyclic AMP phosphodiesterase inhibor(C-AMP PDSI) and S-P-nitrobenzyl-6 -thioniosine(NBT; a sort of NIT) on myocadial preservation and changes of constituent enzyme. Material and method: Twenty-six isolated rabbit hearts were perfused with Krebs-Henseleit buffer solution for 20 minutes arrested for 20 minutes and ten reperfused for 30 minutes. The following four groups were prepared and hemodynamic changes coronary effluent lactate dehydrogenase (LDH) a-hydroxybutylic accid(a-HBD) levels and myocardial LDH creatine kinase-MB (CK-MB) adenosine deaminase(ADA) a-HBD levels and myocardial LDH creatine kinase-MB (CK-MB) adenosine deaminase(ADA) a-HBD levels were analysed before and after cardiac arest ; Group I(control) ; the heart was only perfused with K-H ; Group II ; the heart was perfused with K-H including C-AMP PDSI(Amrinone 25mg/L); Group III ; the heart was perfused with K-H including NBT(4.19mg/L) ; Group IV ; the heart was perfused with K-H including C-AMP PDSI + NBT. Result : Left venticular developed pressure(LVDP) at 10 minutes of the equilibrium was significantly higher in group III(72.1$\pm$5.3 mmHg p<0.01) and group III(72$\pm$5.6 mmHg P<0.025) as compared with group I (40.8$\pm$4.7mmHg) and LVDP at 20 minutes of the reperfusion was significantly higher in group II(74$\pm$5.3mmHg p<0.01) and group III(72$\pm$5.6mmHg p<0.025) as compared with group I (44.2$\pm$4.6mmHg). Percentage recovery of LVDP at the reperfusion was the highest in group II(123.3%) Percentage recovery of coronary flow at the equilibrium reperfusion were higher in group II(310%, 270%) group III(230%, 290%) group IV(310%, 280%) as compared with group I (100%) respectively. Myocadial LDH level was significant lower in group IV(33495$\pm$1802 IU/gm p<0.04) as compared with group I(48767$\pm$1421 IU/gm) Myocadial CK-MB level was significant higher in group II(74820$\pm$1421 IU/gm) compared with group I (45450$\pm$1737 IU/gm) Myocadial ADA level was significant higher group IV(1215$\pm$8 IU/gm p<0.05) compared with group I(125$\pm$15 IU/gm) but there was no significant difference between group I and group II ,III, IV in changes of coronary effluent LDH, a-HBD levels. Conclusion: C-AMP PDSI solely appears to have a better effect on myocardial preservation after ischemia than NBT but with no synergistic effect and it could keep CK-MB leve high in myocardial tissues.

• Journal of Oral Medicine and Pain
• /
• v.30 no.3
• /
• pp.329-336
• /
• 2005

We examined the effect of PQQ, as a scavenger of superoxide, on osteoclast-like cell formation and on mature osteoclast function. To determine whether PQQ scavenges the superoxide, nitroblue tetrazolium (NBT) staining, which is a method to detect superoxide, was performed on HD-11 cells which are a chick myelomonocytic cell line having tartrate-resistant acid phosphatase (TRAP) activity in response to 1,25-dihydroxyvitamin $D_3\;[1,25(OH)_2D_3]$. Histochemical study of TRAP was also performed on HD-11 cells. PQQ inhibited the TRAP-positive multinucleated cell formation of chicken bone marrow cells was also examined. The addition of 20 ${\mu}M$ PQQ inhibited the formation of TRAP-positive multinucleated cell. When chicken osteoclasts were cultured on dentin slices, treatment of 20 ${\mu}M$ PQQ resulted in a significant decrease in dentin resorption by osteoclasts in terms of total resorption area and number of resorption pits. The present data suggest that PQQ, possibly as a scavenger of superoxide ion, inhibits the osteoclastic differentiation and bone resorption.