• Preventive Nutrition and Food Science
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• v.5 no.2
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• pp.86-92
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• 2000

Conjugated linoleic acid(CLA) refers to a collective term of positional and geometric isomers of linoleic acid, which are different in their biological activities. The predominant isomer of CLA in animal tissues is cis-9, trans-11; smaller amounts of trans-10, cis-12 CLA isomers, CLA methyl ester (CLA-ME) was chemically syn-thesized from linoleic acid by the alkaline isomerization method. The synthetic CLA-ME, mainly composed of cis-9, trans-11 CLA and trans-10, cis-12 CLA, was dissolved in acetone, stored at 68$^{\circ}C$ for 1 day, and the supernatant(cis-9, trans-11 CLA-Me) was separated from the precipitate (trans-10, cis-12 CLA-Me). After the processes were repeated three times at -68$^{\circ}C$, the whole processes were repeated three times at -71$^{\circ}C$ in order to increase the purity of these two isomers. The cis-9, trans-11 CLA-Me and trans-10, cis-12 CLA isomers were further purified by the urea adduct. Purities of the cis-9, trans-11 CLA-Me and trans-10, cis-12 CLA-Me were 90.3 and 99.9%, respec-tively. This method could be employed for the preparation of a large quantity of highly purified cis-9, trans-11 CLA-Me or trans-10, cis-12 CLA-Me from synthetic CLA-Me.

• Polymer(Korea)
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• v.35 no.6
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• pp.558-564
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• 2011

The biocompatibility and biodegradability of poly(amino acid) make them ideal candidates for many bio-related applications. Poly(aspartic acid), PASP, is one of synthetic water-soluble polymers with proteinlike structure, and has been extensively explored for the potential industrial and biomedical applications due to its biodegradable, biocompatible and pH-responsive properties. In this work, amino acid-conjugated PASPs were prepared by aminolysis reaction onto polysuccinimide (PSI) using ${\gamma}$-aminobutylic acid(GABA) and ${\beta}$-alanine methyl ester and a subsequent hydrolysis process. Their chemical gels were prepared by crosslinking reaction with ethylene glycol diglycidyl ether (EGDE). The hydrogels were investigated for their basic swelling behavior, hydrolytic degradation and morphology. The crosslinked gels showed a responsive swelling behavior, which was dependent on pH and salt concentration in aqueous solution, and relatively fast hydrolytic degradation.

• Biomolecules & Therapeutics
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• v.27 no.6
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• pp.530-539
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• 2019

Brain aging is an inevitable process characterized by structural and functional changes and is a major risk factor for neurodegenerative diseases. Most brain aging studies are focused on neurons and less on astrocytes which are the most abundant cells in the brain known to be in charge of various functions including the maintenance of brain physical formation, ion homeostasis, and secretion of various extracellular matrix proteins. Altered mitochondrial dynamics, defective mitophagy or mitochondrial damages are causative factors of mitochondrial dysfunction, which is linked to age-related disorders. Etoposide is an anti-cancer reagent which can induce DNA stress and cellular senescence of cancer cell lines. In this study, we investigated whether etoposide induces senescence and functional alterations in cultured rat astrocytes. Senescence-associated ${\beta}$-galactosidase (SA-${\beta}$-gal) activity was used as a cellular senescence marker. The results indicated that etoposide-treated astrocytes showed cellular senescence phenotypes including increased SA-${\beta}$-gal-positive cells number, increased nuclear size and increased senescence-associated secretory phenotypes (SASP) such as IL-6. We also observed a decreased expression of cell cycle markers, including PhosphoHistone H3/Histone H3 and CDK2, and dysregulation of cellular functions based on wound-healing, neuronal protection, and phagocytosis assays. Finally, mitochondrial dysfunction was noted through the determination of mitochondrial membrane potential using tetramethylrhodamine methyl ester (TMRM) and the measurement of mitochondrial oxygen consumption rate (OCR). These data suggest that etoposide can induce cellular senescence and mitochondrial dysfunction in astrocytes which may have implications in brain aging and neurodegenerative conditions.

• The Korean Journal of Mycology
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• v.47 no.3
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• pp.219-232
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• 2019

Chemicals related to hydrogen peroxide ($H_2O_2$) and nitric oxide (NO) generations were exogenously applied to Fusarium oxysporum f. sp. fragariae (Fof) causing Fusarium wilt disease in strawberry plants, and regulations of in vitro conidial germination and mycelial growth of the fungus by the chemical treatments were evaluated. $H_2O_2$ drastically reduced the conidial germination of Fof in a dose-dependent manner, and treatment with 3-amino-1,2,4-triazole (3-AT) catalase inhibitor also led to dose-dependent inhibition of conidial germination but relatively moderately. Gradual decreases in mycelial growth of Fof were found by high concentrations of $H_2O_2$, whilst exogenous 3-AT slightly increased the mycelial growth. Increasing sodium nitroprusside (SNP) NO donor, $N^G$-nitro-l-arginine methyl ester (L-NAME) NO synthase (NOS)-inhibitor and tungstate nitrate reductase (NR) inhibitor led to dose-dependent reductions in conidial germination of Fof in quite different levels. SNP conversely increased the mycelial growth but increasing L-NAME moderately decreased the mycelial growth. Tungstate strongly enhanced mycelial growth. Differentially regulated in vitro mycelial growths of Fof were demonstrated by SNP, L-NAME and tungstate with or without $H_2O_2$ supplement. Superoxide anion production was also regulated during the mycelial growth of Fof by nitric oxide. These results show that $H_2O_2$ and NO-associated enzymes can be suggested as fungal growth regulators of Fof as well as eco-friendly disease-managing agents in strawberry production fields.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.6
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• pp.1158-1163
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• 2011

The present study was aimed to evaluate the soil microbial communities by fatty acid methyl ester (FAME) method in paddy soils at 20 sites in Gyeongnam Province. The soil microbial biomass carbon content of fan and valley $1,266mg\;kg^{-1}$ was higher than alluvial plain $578mg\;kg^{-1}$ (p<0.05). In addition, The dehydrogenase activity of fan and valley $204{\mu}g\;TPF\;g^{-1}\;24h^{-1}$ was higher than alluvial plain $93{\mu}g\;TPF\;g^{-1}\;24h^{-1}$ (p<0.05). The communities of total bacteria and Gram-negative bacteria in the fan and valley paddy soils were significantly higher than those in the alluvial plain paddy soils (p<0.05). Total bacteria communities should be considered as a potential responsible factor for the obvious microbial community differentiation that was observed between the fan and valley and alluvial plain in paddy soils.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.6
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• pp.1176-1180
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• 2011

The present study evaluated the soil microbial communities by fatty acid methyl ester (FAME) method in paddy soils at 11 sites for silt loam, 4 sites for sandy loam, and 5 sites for loam in Gyeongnam Province. The FAME content of fungi in loam ($76nmol\;g^{-1}$) was higher than that of in sandy loam ($45nmol\;g^{-1}$). Sandy loam had significantly lower ratio of cy19:0 to 18:$1{\omega}7c$ compared with that of silt loam (p<0.05), indicating that microbial stress decreased. In addition, actinomycetes community of loam was higher than that of sandy loam.

• Journal of the Korean Applied Science and Technology
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• v.35 no.4
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• pp.1048-1056
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• 2018

Non-edible oil sources (i.e., Palm Acid Oil, waste animal fat) usually contain relatively high amount of free fatty acids (FFA) that make them inadequate for direct base catalyzed transesterification reaction. Enzymatic biodiesel synthesis can solve several problems posed by the alkaline-catalyzed transesterification, and has certain advantages over the chemical catalysis of transesterification, as it is less energy intensive, allows easy recovery of glycerol and the transesterification of glycerides with high free fatty acid contents. In this study, we synthesized biodiesel through enzymatic catalyzed process using high free fatty acid containing waste oil in biodiesel reactor (1 ton/day) and optimized the biodiesel production processes.

• Journal of Pharmacopuncture
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• v.22 no.3
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• pp.160-165
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• 2019

Objectives: The aim of this study was to evaluate the effect of Ribes khorasanicum (R. khorasanicum); a plant growing in north Khorasan of Iran; on cardiovascular and stress oxidative in acute hypertension induced by N-nitro-l-arginine methyl ester (L-NAME), anitric oxide synthase inhibitor. Methods: Rats were divided into Control, L-NAME (10 mg/kg), Sodium Nitroprusside (SNP) (50 mg/kg) + L-NAME and three treated groups with R. khorasanicum (4, 12 and 24 mg/kg) groups + L-NAME. L-NAME and SNP were injected intravenously and extract intraperitoneal. In R. khorasanicum groups, L-NAME was injected 30 min after injection of the extract. Systolic blood pressure (SBP), mean arterial pressure (MAP) and heart rate (HR) were recorded continuously using power lab software. At the end of study oxidative stress parameters including of total thiol content (SH), malondialdehyde (MDA), superoxide dismutase (SOD) and catalase (CAT) in heart and aorta of all groups were also measured. Results: In groups 4 and 24 mg/kg extract +L-NAME, there was a non-significant decrease in SBP and MAP compared to L-NAME group but dose 12 mg/kg significantly attenuate the effect of L-NAME(P < 0.05). In L-NAME group the heart and aorta tissues antioxidant enzymes levels decreased, while in treated rats these enzymes significantly increased. Conclusion: The extract of R. khorasanicum in dose 12 mg/kg show anti-hypertensive effect that is mediated by an effect on NO system or antioxidant parameters.

• Integrative Medicine Research
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• v.6 no.2
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• pp.149-155
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• 2017

Background: Naringenin (NRG) is a common dietary polyphenolic constituent of fruits. NRG has diverse pharmacological activities, and is used in traditional medicine to treat various diseases including gastrointestinal (GI) disorders. Interstitial cells of Cajal (ICCs) are pacemaker cells of the GI tract. In this study, the authors investigated the effects of NRG on ICCs and on GI motility in vitro and in vivo. Methods: ICCs were dissociated from mouse small intestines by enzymatic digestion. The whole-cell patch clamp configuration was used to record pacemaker potentials in cultured ICC clusters. The effects of NRG on GI motility were investigated by calculating percent intestinal transit rates (ITR) using Evans blue in normal mice. Results: NRG inhibited ICC pacemaker potentials in a dose-dependent manner. In the presence of tetraethylammonium chloride or iberiotoxin, NRG had no effect on pacemaker potentials, but it continued to block pacemaker potentials in the presence of glibenclamide. Preincubation with SQ-22536 had no effect on pacemaker potentials or on their inhibition by NRG. However, 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one blocked pacemaker potential inhibition by NRG. In addition, L-NG-nitroarginine methyl ester blocked pacemaker potential inhibition by NRG. Furthermore, NRG significantly suppressed murine ITR enhancement by neostigmine in vivo. Conclusion: This study shows NRG dose-dependently inhibits ICC pacemaker potentials via a cyclic guanosine monophosphate/nitric oxide-dependent pathway and $Ca^{2+}$-activated $K^+$ channels in vitro. In addition, NRG suppressed neostigmine enhancement of ITR in vivo.

• Microbiology and Biotechnology Letters
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• v.46 no.4
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• pp.377-389
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• 2018

In this study, a novel microalgal strain, Desmodesmus sp. KAERI-NJ5, was isolated, identified, and evaluated as a candidate for biodiesel feedstock. In a preliminary study, the effects of four general microalgal growth factors, including temperature, pH, light intensity, and concentration of nitrogen source ($KNO_3$), on the microalgal photoautotrophic growth were evaluated. With the exception of light intensity, the growth factors needed to be optimized for the microalgal biomass production. Optimization was done using response surface methodology. The optimal conditions for biomass production were pH 6.54, $27.66^{\circ}C$, and 0.52 g/l $KNO_3$. The biomass production at the optimal conditions was 1.55 g/l, which correlated well with the predicted value of 1.5 g/l. The total lipid and fatty acid methyl ester contents of the cells grown at the optimal conditions were 49% and 21.2% of cell dry weight, respectively. To increase the lipid content of the biomass, microalgae were challenged by nitrogen starvation. Enhancement of total lipid and fatty acid content up to 52.02% and 49%, respectively, were observed. Lipid analysis of the nitrogen-starved cells revealed that C16 and C18 species accounted for 95.9% of the total fatty acids. Among them, palmitic acid (46.17%) and oleic acid (39.43%) dominantly constituted the algal fatty acids. These results suggest Desmodesmus sp. KAERI-NJ5 as a promising feedstock for biodiesel production.