• Asian-Australasian Journal of Animal Sciences
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• v.24 no.3
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• pp.379-385
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• 2011

Ferulic acid esterase (FAE) and acetyl esterase (AE) cleave feruloyl groups substituted at the 5'-OH group of arabinosyl residues and acetyl groups substituted at O-2/O-3 of the xylan backbone, respectively, of arabinoxylans in the cell wall of grasses. In this study, the enzyme profiles of FAE, AE and polysaccharide hydrolases of the anaerobic rumen fungus Neocallimastix sp. YQ1 grown on Chinese wildrye grass hay (CW) or alfalfa hay (AH) were investigated by two $2{\times}4$ factorial experiments, each in 10-day pure cultures. The treatments consisted of two glucose levels ($G^+$: glucose at 1.0 g/L, $G^-$: no glucose) and four N sources (N1: 1.0 g/L yeast extract, 1.0 g/L tryptone and 0.5 g/L $(NH_4)_2SO_4$; N2: 2.8 g/L yeast extract and 0.5 g/L $(NH_4)_2SO_4$; N3: 1.6 g/L tryptone and 0.5 g/L $(NH_4)_2SO_4$; N4: 1.4 g/L tryptone and 1.7 g/L yeast extract) in defined media. The optimal combinations of glucose level and N source for the fungus on CW, instead of AH, were $G^-N4$ and $G^-N3$ for maximum production of FAE and AE, respectively. Xylanase activity peaked on day 4 and day 6 for the fungus grown on CW and AH, respectively. The activities of esterases were positively correlated with those of xylanase and carboxymethyl cellulase. The fungus grown on CW exhibited a greater volatile fatty acid production than on AH with a greater release of ferulic acid from plant cell wall.

• Applied Biological Chemistry
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• v.14 no.3
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• pp.229-235
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• 1971

Kwanok, Fujisaka #5, Paldal, and Suwon #82 as japonica type and IR-262 and CP-slo as indica type of rice seeds were selected for this experiment among varieties grown in Korea. Activities of crude enzymes extracted from germinating seeds of these varieties on malathion and p-nitrophenyl acetate as substrates, esterase zymograms with 1-naphthyl acetate as substrate, and some observations are summarized as follows: 1. Activities per unit volume of crude enzyme preparations on malathion were in the order of Kwanok>IR-262>Fujisaka #5>CP-slo>Paldal>Suwon #82. 2. Esterase zymograms on agar-gel electrophoretograms exhibited three to four bands two electrodes with little difference among varieties, nevertheless showing a wide and strongly-colored band toward cathode. Suwon #82 has a somewhat different pattern from others. 3. Enzyme activities per milligram protein with p-nitrophenyl acetate as substrate were in the order of CP-slo>IR-262>Paldal>Kwanok>Suwon #82>Fujisaka #5, indicating that activities of indica type are much stronger than those of japonica type, but not in agreement with results with malathion. 4. Malathion did not much inhibit the esterase activity at the concentration of 0.2PPM on electrophoretograms. 5. It is supposed that there is a complex esterase system hydrolyzing malathion and p-nitrophenyl acetate in germinating rice seeds.

• Journal of Microbiology and Biotechnology
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• v.19 no.2
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• pp.187-193
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• 2009

A metagenomic library of surface-water microbes from the Yangtze River in China was constructed, and a novel esterase, designated as EstY, was isolated and characterized. EstY had 423 amino acids with an estimated molecular mass of 44 kDa and pI of 7.28. It hydrolyzed various p-nitrophenyl esters(acetate, butyrate, caprate, caprylate, laurate, myristate, and palmitate) and its best substrate was p-nitrophenyl caprate(C8). The optimum pH for EstY activity was 9.0 and the optimum temperature was $50^{\circ}C$. Metal ions, such as $Mn^{2+},\;Co^{2+},\;Hg^{2+},\;Zn^{2+},\;and\;Fe^{3+}$, strongly inhibited the activity of EstY, whereas $Mg^{2+}$ was required for maximal activity. Activity remained in the presence of 10% alcohol, acetone, isopropanol, and dimethyl sulfoxide, respectively. An analysis of the amino acid sequence deduced from estY revealed that it had 7 closely related lipolytic enzymes. Moreover, a sequence analysis showed that EstY, like its 7 relatives, did not belong to any known lipolytic enzyme family.

• The Korean Journal of Pesticide Science
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• v.11 no.3
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• pp.171-178
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• 2007

Esterase isozymes were extracted from final instar larvae of M. saltuarius treated with selective diets and inhibitors. Twenty esterase isozymes were separated on 12% native-PAGE gel and stained with three different substrates(${\alpha}$-naphthyl acetate, ${\beta}$-naphthyl acetate, or ${\alpha}$-naphthyl butyrate). Interestingly, the isozymes of Est7(${\alpha}$-naphthyl acetate and ${\alpha}$-naphthyl butyrate) and Est6(${\beta}$-naphthyl acetate) were specifically activated in final instar larvae fed with the bark of Pinus koraiensis. However, we could not find any band from substrate ${\beta}$-naphthyl stearate. The esterase activities of Est3, Est6, and Est7 were inhibited by organophosphate and carbamate insecticides. In addition, The esterase activities of Est4, Est6, and Est7 were also inhibited by eserine. However, inhibition of esterase activities in methoprene, bornyl acetate, linal, cineol, and citral was not observed. However, It is necessary to reconfirm these results in vivo.

• 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.44 no.1
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• pp.52-57
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• 2011

Termites play an important role in the degradation of dead plant materials and have acquired endogenous and symbiotic cellulose digestion capabilities. The feruloyl esterase enzyme (FAE) gene amplified from the metagenomic DNA of Coptotermes formosanus gut was cloned in the TA cloning vector and subcloned into a pET32a expression vector. The Ft3-7 gene has 84% sequence identity with Clostridium saccharolyticum and shows amino acid sequence identity with predicted xylanase/chitin deacetylase and endo-1,4-beta-xylanase. The sequence analysis reveals that probably Ft3-7 could be a new gene and that its molecular mass was 18.5 kDa. The activity of the recombinant enzyme (Ft3-7) produced in Escherichia coli (E.coli) was 21.4 U with substrate ethyl ferulate and its specific activity was 24.6 U/mg protein. The optimum pH and temperature for enzyme activity were 7.0 and $37^{\circ}C$, respectively. The substrate utilization preferences and sequence similarity of the Ft3-7 place it in the type-D sub-class of FAE.

• Journal of Life Science
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• v.20 no.9
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• pp.1306-1313
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• 2010

The gene encoding esterase enzyme was cloned from a metagenomic library of cow rumen bacteria. The esterase gene (est1R) was 2,465 bp in length, encoding a protein of 366 amino acid residues, and the molecular weight of the enzyme was 61,166 Da. Est1R of rumen cosmid library shared 5.9% amino acid identity with Est1R (P37967) of PNB carboxylesterase, 6.1% with Est1R (1EEAA) of acetylcholinesterase and 6.1% with Est1R (1H23A) of chain A. BlastP in NCBI database analysis of Est1R revealed that it was not homologous to previous known lipases and esterases. Est1R showed optimum activity at pH 7.0 and $40^{\circ}C$. On the other hand, the enzyme was found to be most active without organic solvent, followed by 95% activity with methanol, and the enzyme activity was highly affected by hexane (lost 51% activity). Therefore, the novel esterase gene est1R is likely obtainable from cow rumen metagenome and may be utilized for industrial purposes.

• Journal of Physiology & Pathology in Korean Medicine
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• v.16 no.6
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• pp.1236-1242
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• 2002

In order to make an efficient prescription and cope with dementia, learning and memory functions of Sprague-Dawley model rats were tested with Morris water maze. And to evaluate the effect of the sample drug(CHM) on choline acetyltranferase and acetylcholine esterase, immunoreactive measurement and enzymatic activity measuring were carried out. Rats were injected with ibotenic acid through hippocampus CA1 and CA3 area. The results are as following. CHM improves the learning ability in the acquisition test and memory function in the retention test significantly. And CHM increases the level of AChE which is resolving acetylcholine. Though it doesn't increase the level of ChAT significantly which is synthesizing acetylcholine, but it shows the tendency of increase. So these results show that CHM improve the cholinergic catabolism and anabolism, and the increment of metabolic activity of cholinergic system. Thus it can be concluded that CHM will be helpful to cholinergic brain disease induced by primary or senile reduction of acetylcholine secretive activity.

• Applied Biological Chemistry
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• v.42 no.4
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• pp.336-343
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• 1999

Fifty six mycelial cultured Basidiomycetes were screened for their inhibitory effects against prolyl endopeptidase(PEP), acetylcholine esterase(AChE) and thrombus coagulation. Out of them, methanolic extract of mycelium and/or ethylacetate(EtOAc) soluble fraction from culture broth of Peniophora quercina, Amanita aspera, Phellinus chrysoloma, Grifola frondosa, Wolfiporia extensa, Clavicorona pyxidata and Phanerochaete sordida inhibited more than 90% of PEP activity at 40 ppm. The extracts of Lenzites betulina, Phellinus chrysoloma, Wolfiporia extensa, Phanerochaete sorrlida, Hypocrea nigricans, Coriolus azureus, Flammulina velutipes, Phlebiopsis gigantea and Bondarzewia montana exhibited about 40% of inhibitory activity against AChE at 40 ppm. In thrombin times assay, the extracts of Amanita aspera, Oxyporus latemarginata, Peniophora quercina, Fomes fomenfarius, Trametes versicolor, and Phlebiopsis gigantea delayed coagulation of thrombus about two to three times over control at ca 550 ppm. In activated partial thromboplastin times assay, none of the tested Basidiomycetes showed significant effect.

• Korean Journal of Food Science and Technology
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• v.40 no.3
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• pp.251-256
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• 2008

Eoyukjang is a traditional sauce-type of Korean food that is similar to a soybean sauce made from fermented soybeans, and it is produced from a fermented mixture of sea foods, meats, and meju (soybean paste). This study examined periodical changes in the enzymatic activities of ${\alpha}$-amylase, esterase, ${\beta}$-glucosidase, protease, lipase, and lipoxygenase within the culture broth and solids of eoyukjang during 1 year of fermentation. The eoyukjang solids had 234-532% higher protein content than the culture broth. The specific activities of ${\alpha}$-amylase, esterase, ${\beta}$-glucosidase, and protease increased in both the culture broth and solids. Particularly, in the culture broth, ${\alpha}$-amylase, esterase, ${\beta}$-glucosidase, and protease activities rapidly increased (3- to 8-fold) until 10 months of fermentation, and then drastically decreased. However, the activities of lipase and lipoxygenase in both the culture broth and solids were less than 0.05 unit/mg of protein, respectively, throughout fermentation; thus, their activity levels were low and changed little over the 12 months. Overall, while the solids had higher protein content than the culture broth, the broth had greater enzyme activity levels during eoyukjang preparation.