• Journal of Life Science
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• v.11 no.4
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• pp.335-339
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• 2001

Cancer chemoprevention refers to the use of natural or synthetic substances to prevent initiational and promotional events that occur during the process of carcinogenesis. Thesium Chinese Turczaninow aqua-acupuncture solution (TCTAS) and Astragli Radix aqua-acupuncture solution (ARAS) were tested as the cancer chemopreventive agents using biochemical markers of carcinogenesis. The effects on the inhibition of phorbol 12- myristate 13-acetate(TPA)-induced free radical formation in HL-60 cells and the inhibition of polyamine metabolism were measured. There is significant inhibition of TAP-induced free radical formation in human leukemic cells with cells with ARAS. Proliferation of Acanthamoeba castellanii was inhibited by TCTAS and ARAS. TCTAS and ARAS positive in these assays may inhibit the carcinogenesis process and is considered promising cancer-preventing agents.

• Korean Journal of Environmental Biology
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• v.23 no.4
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• pp.390-397
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• 2005

The inhibition of cell recovery might be proceeded via either the damage of the mechanism of the recovery itself or via the formation of irreversible damage which could not be repaired at all. Both these processes may take place at the same time. Any of these possibilities would result in a decrease in both the rate and extent of cell recovery. To distinguish them, a quantitative approach describing the process of recovery as a decrease in the effective radiation dose was applied to experimental data on the recovery from potentially lethal damage in Chinese hamster cells exposed to X-rays alone or combined with various chemicals (pyruvate, novobiocin, lactate, nalidixic acid, 3-aminobenzamide). For these particular cases, it is concluded that the recovery process itself is not damaged and the inhibition of the recovery is entirely due to the enhanced yield of the irreversibly damaged cells.

• Journal of the Korean institute of surface engineering
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• v.36 no.5
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• pp.364-372
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• 2003

In continuous galvanizing process, dissolution of iron into molten zinc results in a fairly great amount of dross. In order to decrease dross, the amount of dissolved iron of strip in molten zinc was investigated in the range of 0∼0.22%Al content, 440∼$470^{\circ}C$ strip temperature and 3∼60 sec dipping time. Uniform Fe-Al-Zn inhibition layer was formed in the coating layer/strip interface not only in the grain boundary but also in the grain of substrate with the increase of Al content in the zinc pot, while the amount of iron dissolution was decreased. Inhibition layer was unstable as the dipping time and strip temperature increased and the amount of iron dissolution increased.

• Corrosion Science and Technology
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• v.22 no.1
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• pp.10-20
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• 2023

Because of its inexpensive cost, mild steel is frequently employed as a construction material in different industries. Unfortunately, because of its limited resistance to corrosion, a protective layer must be applied to keep it from decaying in acidic or basic environments. The presence of heteroatoms, such as nitrogen, oxygen, and pi-electrons in the Schiff base could cause effective adsorption on the mild steel surface, preventing corrosion. The weight loss method and scanning electron microscopy (SEM) were used to investigate the inhibitory effects of APIDO on mild steel in a 1 M hydrochloric acid environment. The efficiency of inhibition increased as the inhibitor concentration increased and decreased as the temperature increased. The SEM analysis confirmed that the corrosion inhibition of APIDO proceeded by the formation of an organic protective layer over the mild steel surface by the adsorption process. Simulations based on the density functional theory are used to associate inhibitory efficacy with basic molecular characteristics. The findings acquired were compatible with the experimental information provided in the research.

• Journal of the Korean Chemical Society
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• v.55 no.3
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• pp.364-372
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• 2011

The corrosion inhibition of imatinib mesylate (IMT) on mild steel in 0.25 M sulphuric acid has been studied using gravimetric and potentiodynamic polarization techniques at various concentrations of inhibitor, temperature and fluid velocities. The results obtained showed that, inhibition efficiency (% IE) increases with increasing concentration of the inhibitor. The adsorption process on mild steel surface follows Langmuir adsorption isotherm. The values of Gibbs free energies of adsorption obtained suggest that, the adsorption process of IMT on mild steel is chemisorption. Thermodynamic parameters were evaluated and discussed. The electron orbital density distribution of HOMO and LUMO of IMT was used to discuss the inhibition mechanism. FT-IR spectroscopy and SEM images were used to analyze the surface adsorbed film.

• KSBB Journal
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• v.23 no.3
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• pp.239-244
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• 2008

For physiological function of aloe concentrate by ultrafiltration (UF) process, jack bean urease inhibitory activity and bentonite flocculating activity of UF aloe concentrate was investigated and compared with fresh aloe gel. Urease inhibitory activity of UF aloe concentrate ranged from 87 to 90% in 1 mL sample. Also, urease inhibitory activity of UF aloe concentrate increased about 10% by heat treatment showing the heat stability. From Lineweaver-Burk plot for UF aloe concentrate, urease inhibition pattern indicated general non-competitive inhibition. From flocculation test of UF aloe concentrate about 1% (w/v) bentonite suspension, maximum flocclulating activity of 97% was obtained at 0.5 mL addition of UF aloe concentrate/ 5 ml bentonite suspension. However, flocculating activity of 81% was obtained at 1 mL addition of UF aloe concentrate/ 5 mL bentonite suspension, which was typical flocculating behavior of polymers with re-dispersion at overdose area. FT-IR spectra of UF aloe concentrate showed the characteristic patterns of $\beta$-binding polysaccharide and less deacetylation indicating higher level of bioactive polysaccharide content.

• International journal of advanced smart convergence
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• v.10 no.4
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• pp.225-232
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• 2021

Obesity is caused by the accumulation of triglycerides in adipocytes by the differentiation and lipid synthesis process of pre-adipocytes, and excessive accumulation of adipocytes by the activated Adipogenesis process within the differentiated cells. Therefore, inhibiting the differentiation of adipocyte cells or controlling the adipogenesis process is known as an effective treatment method for obesity. This study evaluates the inhibition of Red beet root extract on pancreatic lipase and pre-adipocyte cell differentiation. Also it evaluates the Red beet root extract activities on C/EBP-𝛼,𝛽, and PPAR-𝛄. The experiments proved that the Red beet root extract inhibits pancreatic lipase by concentration dependency. Further, in 3T3-L1 inhabitation experiment, it was found Red beet root extract inhibited adipocyte formation. Red beet root extract also inhibits the expression of C/EBP-𝛼, C/EBP-𝛽, and PPAR-𝛾 which effect the process of adipocytic differentiation. We therefore concluded that RBE has a high potential to further studies on anti-obesity effect.

• BMB Reports
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• v.32 no.4
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• pp.385-392
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• 1999

The $NAD^+$-specific activity of a dual coenzyme-specific isocitrate dehydrogenase (IDH; EC 1.1.1.41) from the primitive fungus Pythium ultimum was investigated to elucidate the regulatory factors that may influence the intracellular distribution of carbon and the availability of intermediates, e.g. citrate, for fatty acid synthesis. Inhibition of $NAD^+$-IDH activity by diphospho- and triphosphonucleotides (ATP, ADP, and GTP) reflected the sensitivity of this enzyme to cellular energy charge even though monophosphonucleotides (AMP and GMP) had little effect on activity. NADPH, but not NADH, substantially inhibited $NAD^+$-IDH activity, showing noncompetitive inhibition with isocitrate. Oxalacetate and ${\alpha}$-ketoglutarate showed competitive inhibition with isocitrate, while citrate and cis-aconitate showed mixed-noncompetitive inhibition with isocitrate. Inhibition by these substances ranged from 29 to 46% at 10 mM. The inhibitory effect of oxalacetate was increased synergistically by glyoxylate, which alone caused 31% uncompetitive inhibition at 10 mM, and a mixture of the two substances at 1 mM each showed 98% inhibition of $NAD^+$-IDH activity. The regulation of $NAD^+$-IDH in Pythium ultimum seems to be a complex process involving mitochondrial metabolites. The addition of glyoxylate (3 mM) and oxalacetate (3 mM) to the culture medium resulted in the production of 49% more lipid by P. ultimum.

• Bulletin of the Korean Chemical Society
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• v.28 no.5
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• pp.758-762
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• 2007

A new alkyldithiocarbonate (xanthate), as sodium salts, C2H5OCS2Na, was synthesized by the reaction between CS2 with ethyl alcohol in the presence of NaOH. The new xanthate was characterized by 1H NMR, IR and elemental analysis. Then, the new synthesized compound was examined for functional study of cresolase activity of Mushroom Tyrosinase (MT) from a commercial source of Agricus bisporus in 10 mM phosphate buffer pH 6.8, at three temperatures of 10, 20 and 33℃ using UV spectrophotemetry. 4-[(4-methylphenyl)- azo]-phenol (MePAPh) was used as a synthetic substrate for the enzyme for cresolase reaction. The results show that ethyl xanthate can activate or inhibit the cresolase activity of mushroom tyrosinase depending to the concentration of ethyl xanthate. It was concluded that the enzyme has two distinct sites for ethyl xanthate. The first one is a high-affinity activation site and the other is a low-affinity inhibition site. Activation of the enzyme in the low concentration of ethyl xanthate arises from increasing the affinity of binding for the substrate as well as increasing the enzyme catalytic constant. The affinity of ligand binding in the activation site is decreased by increasing of the temperature, which is the opposite result for the inhibition site. Hence, the nature of the interaction of ethyl xanthate is different in two distinct sites. The binding process for cresolase inhibition is only entropy driven, meanwhile the binding process for cresolase activation is not only entropy driven but also enthalpy driven means that hydrophobic interaction is more important in the inhibition site.

• Journal of the Korean institute of surface engineering
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• v.45 no.2
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• pp.70-74
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• 2012

In thermal barrier coating (TBC) systems, the life of the coating depends on thermally grown oxide (TGO) layer because most of the failure of TBCs occurs when TGO growth increases. In order to inhibit TGO growth, process was additionally carried out before the heat treatment of the TBC coating layer at $1200^{\circ}C$ in air. In the additional process, heat treatment in vacuum furnace of < $10^{-5}$ torr was conducted for 7 h and 14 h before the heat treatment. The area and length of TGO, as well as the crack length in the TBC were characterized using a scanning electron microscope (SEM). The TGO thickness and crack of specimens pre-heat treated in vacuum furnace were reduced by 45% compare to those heat treated in furnace. Consequently, pre-heat treatment in a vacuum furnace process lead to effective inhibition of growth of the TGO.