• Journal of Plant Biology
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• v.35 no.1
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• pp.9-15
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• 1992

The plantlet was regenerated on MS medium containing BAP (2 mg/I) and 1M (1 mg/I) from leaf discs of pepper after 3 weeks of culture. And then, we investigated the activity of peroxidase and esterase and the pattern of their isozymes from leaf, stem and root in order to observe physiological and biochemical changes on the developemental stage, respectively. The peroxidase was expressed with tissue specificity because peroxidase activity according to the developemental stage of the tissue was not only highest in the leaf of the pepper at 10 days after it germinated but also 2 new bands of its isozyme were found in pI 7.2 and pI 5.2. However, a new pI 3.4 band was found in the leaf and root of the pepper after 14 days of germination, and in the stem was found out pI 5.2 band. As regeneration of leaf dises was progressed, its peroxiase activity was increased about 80% more than that of control after 14 days of culture and new pI 3.2 and 6.5 bands of it isozyme were found. The results suggested that peroxidase would be connected with regeneration of pepper. Also, esterase activity was increased about 50% more than that of control after 14 days of culture, the pattern of esterase isozyme was shown to be 3 cathodic bands and 1 anodic band after 7 days of culture.ulture.

• The Korean Journal of Zoology
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• v.39 no.2
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• pp.190-197
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• 1996

The optimal conditions and substrate specificity of whole body esterase (EST) activity, effects of inhibitors (Eserine, Paraoxon, p-HMB, DDVP, DFP) on the enzyme, and ontogenv of the isozymes were determined in Lucilio ilfustris Meisen. The optimal temperature was $45^{\circ}C$ regardless of kind of reacted substrate, $\alpha-naphthyl$ acetate $(\alpha-Nal,$ a.naphthvl butylate $(\alpha-N),$ and Pnaphthyl acetate $(\beta-Na),$ but the optimal pH showed some regioselectivitv to naphthvl group of the esters; PH 7.0 for Iform, pH 7.5 for a-form. The maximum reaction rate was recorded at about 2.5 $\times$ 10's M of PNa and etNa, but 1.0 $\times$ 10'S M of $\alpha-Nb.$ Among the five EST inhibitors tested, DDVP was the most powerful. However, distinction of the relative specificity of inhibitors between three body parts, head, thorax, and abdomen, was shouts, representing differences in the distribution and activity of isozvmes. Of 12 carboxyl-esterases (CE), 8 cholinesterases (ChE) and 2 arvlesterases (ArE) identified based on their inhibitor specificity throughout the development, two larval and prepupal stage specific ChEs, no pupal specific, and 2 CEs.2ChEs. and one ArE adult specific isozvmes were confirmed.

• Korean Journal of Food Science and Technology
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• v.32 no.1
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• pp.200-205
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• 2000

Ethanol extract of Alpiniae Katsumadaii semen inhibited potently cholesterol esterase activity in vitro. Chloroform fraction of ethanol extract showed the stronger inhibitory effect than other solvent fractions-ethylacetate fraction, butanol fraction, and aqueous fraction. The chloroform frac ion of Alpiniae katsumadaii semen were studied as a candidator of plasma cholesterol lowering material in high cholesterol-fed rats. In high cholesterol-fed rats, the diet with chloroform fraction of 100 mg/kg and 150 mg/kg lowered not only plasma neutral lipids contents 25.9% and 26.5% but also plasma total cholesterol level 11.8% and 20.8%, respectively. Plasma HDL-cholesterol level and Atherogenic Index(AI) in Alpiniae chloroform fraction-fed rats were recovered as those level of normal rats.

• Journal of agriculture & life science
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• v.46 no.3
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• pp.109-118
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• 2012

The gene encoding an esterase enzyme was cloned from a metagenomic library of cow rumen bacteria. The esterase gene (est2R) was 2,120 bp in length, encoding a protein of 516 amino acid residues with a calculated molecular weight of 57,286 Da. The molecular weight of the enzyme was estimated to be 57,000 Da by SDS-PAGE. Est2R shared 35.6% amino acid identity with esterase (CAH19079) of uncultured prokaryote. The Est2R was most active at $20-40^{\circ}C$, and showed optimum at $30^{\circ}C$ and pH 8.0. The most activity of Est2R for the different chain length of p-nitrophenyl ester group as substrate was p-nitrophenyl acetate. Moreover, the enzyme was found to be most active without organic solvent, followed by 98% active with ethanol, and the enzyme activity was highly affected by the acetonitrile. The enzyme was significantly inhibited by $Zn^{2+}$ but stimulated by $Ca^{2+}$. So, novel esterase gene est2R is likely to obtain from cow rumen metagenome and supposed to use for industrial purpose.

• Bulletin of the Korean Chemical Society
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• v.31 no.1
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• pp.157-161
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• 2010

A sensory element against carbaryl, as a widely used pesticide was prepared based on adsorbed acetylcholine esterase (AChE) from Torpedo california. Octadecyl was substituted on macro-porous silica, confirmed by infra-red (IR) spectroscopy and quantitatively estimated through thermo-gravimetric analysis (TGA). Immobilization of the enzyme was achieved by adsorption on this support. Activity of the immobilization product was measured as a function of the loaded enzyme concentration, and maximum binding capacity of the support was estimated to be 43.18 nmol.mg-1. The immobilized preparations were stable for more than two months at storage conditions and showed consistency in continuous operations. Possible application of the immobilized AChE for quantitative analysis of carbaryl is proposed in this study.

• Korean journal of applied entomology
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• v.34 no.2
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• pp.112-119
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• 1995

Anatomical and biochemical changes of the corn root injured by the root lesion nematode, Pratylenchus vulnus, were examined to understand the interactions between the nematode and the crop which can be applied to a breeding program for nematode-resistant crop. The nematode and the crop which can be applied to be a breeding program for nematode-resistant crop. The nematode entered the cortex of corn root through its epidemis. They moved to other cortical cells by breaking their cell walls. They, finally, gathered around the endodermis of the roots and the bases of the root hairs. Parasitism of the nematode formed cavities within the root tissues where the females laid eggs. Major root damage by the nematode occurred in the cortical cells where must cell walls were broken and crushed to form empty spaces. These empty spaces in the base of the root resulted in this breakdown. Damage-induced biochemical changes of the corn roots were analysed by their total protein patterns and esterase activities in both control and nematode-infected roots. Denaturing gel did not show any significant difference in the banding patterns between them. Esterase patterns and activities, also, were not significantly different between the infected and the control roots.

• BMB Reports
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• v.29 no.3
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• pp.225-229
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• 1996

Effects on thrombin by an amphipathic cation, dequalinium, which has been recognized as an anticarcinoma agent were investigated with small chromogenic substrates such as Na-benzoyl-DL-argininep-nitroanilide (BApNA), H-D-phenylalanyl-L-pipecoyl-L-arginine-p-nitroanilide (S-2238), and Na-p-tosyl-L-arginine methyl ester (TAME). Among them, only TAME hydrolysis due to an esterase activity of the enzyme was significantly activated to 81% at 20 ${\mu}M$ dequalinium in the absence of NaCl. This stimulation became even higher in the presence of 0.2 M NaCl to 3.5-fold at 60 ${\mu}M$ dequalinium. This specific activation of thrombin was well correlated with the results of in vitro coagulation tests measuring the activated partial thromboplastin time (APTT) and the prothrombin time (PT) It is pertinent. therefore, to suggest that the esterase activity should be examined in addition to the effects on 5-2238 hydrolysis when especially any regulators not directed to an active site of thrombin need to be studied. We also expect that dequalinium could be a useful tool for studying structure-function relationship of thrombin and blood coagulation.

• The Korean Journal of Mycology
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• v.17 no.4
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• pp.197-201
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• 1989

The fusion between protoplasts of Ganoderma applanatum and oidia of Lyophyllum ulmarium (Hypsizigus marmoreus) was induced with polyethylene glycol and $CaCl_2$. When transferred to Ganoderma complete medium plates, fusants showed mixed morphologies both parents. During three times subcultivation the fusants were changed similar to those of L. ulmarium type. All fusants produced oidia, clamp connections and basidiocarps similar to those of L. ulmarium. Isozyme pattern of esterase of interorder fusants showed both parental and non-parental bands. Each individual fusant did not showed both parental and non-parental bands. Each individual fusant did not show any differences in mycelial growth rate, colony morphology, esterase band pattern and basidiocarp.

• Journal of Microbiology and Biotechnology
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• v.22 no.9
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• pp.1245-1252
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• 2012

Acinetobacter venetians V28 was isolated from the intestine of righteye flounder, Poecilopsetta plinthus caught in Vietnam seawater, and the esterase gene was cloned using a shotgun method. The amino acid sequence deduced from the nucleotide sequence (1,017 bp) corresponded to a protein of 338 amino acid residues with a molecular weight of 37,186. The esterase had 87% and 72% identities with the lipases of A. junii SH205 and A. calcoaceticus RUH2202, respectively. The esterase contained a putative leader sequence, as well as the conserved catalytic triad (Ser, His, Asp), consensus pentapeptide GXSXG, and oxyanion hole sequence (HG). The protein from the strain V28 was produced in both a soluble and an insoluble form when the Escherichia coli cells harboring the gene were cultured at $18^{\circ}C$. The maximal activity of the purified enzyme was observed at a temperature of $40^{\circ}C$ and pH 9.0 using p-NP-caprylate as substrate; however, relative activity still reached to 70% even at $5^{\circ}C$ with an activation energy of 3.36 kcal/mol, which indicated that it was a cold-adapted enzyme. The enzyme was a nonmetallo-protein and was active against p-nitrophenyl esters of $C_4$, $C_8$, and $C_{14}$. Remarkably, this enzyme retained much of its activity in the presence of commercial detergents and organic solvents. This cold-adapted esterase will be applicable as catalysts for reaction in the presence of organic solvents and detergents.

• Microbiology and Biotechnology Letters
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• v.40 no.4
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• pp.389-395
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• 2012

T-RFLP (terminal restriction fragment length polymorphism) analysis, one of the most highly adopted culture-independent microbial community analysis methods, was applied to evaluate the colonization of probiotics in experimental animal gut. Lactic acid bacteria that exhibited cinnamoyl esterase activity were isolated from Korean fermented vegetables and identified by 16S ribosomal RNA sequence analysis. Lactobacillus plantarum KK3, which demonstrated high chlorogenic acid hydrolysis by cinnamoyl esterase activity, and acid/bile salt resistances, was cultured, freeze-dried, and fed to mice and the microbiota in their feces were monitored by T-RFLP analysis. The T-RF of L. plantarum was detected in the feces of mice after the start of administration and lasted at least 31 days after the initial 7 day feeding. T-RFLP analysis was considered a useful tool to evaluate the gut colonization of probiotic L. plantarum. In order to prove that L. plantarum was from viable cells, we reisolated L. plantarum in the feces using cinnamoyl esterase activity media as the screening step. The colonization of L. plantarum KK3 in the mouse gut was confirmed by this research.