DSpace community: 生命科學研究所

Pro-angiogenic effects of chalcone derivatives in zebrafish embryos in vivo

Sat, 01 Aug 2015 15:43:15 GMT

title: Pro-angiogenic effects of chalcone derivatives in zebrafish embryos in vivo

Nephroprotective role of resveratrol and ursolic acid in aristolochic acid intoxicated zebrafish

Sat, 01 Aug 2015 15:32:40 GMT

title: Nephroprotective role of resveratrol and ursolic acid in aristolochic acid intoxicated zebrafish

Knocking down 10-formyltetrahydrofolate dehydrogenase increased oxidative stress and impeded zebrafish embryogenesis by obstructing morphogenetic movement

Sat, 01 Aug 2015 15:27:23 GMT

title: Knocking down 10-formyltetrahydrofolate dehydrogenase increased oxidative stress and impeded zebrafish embryogenesis by obstructing morphogenetic movement

Mechanism for controlling the monomer-dimer conversion of SARS coronavirus main protease

Sat, 01 Aug 2015 15:17:08 GMT

title: Mechanism for controlling the monomer-dimer conversion of SARS coronavirus main protease

Inactivation of myosin binding protein C homolog in zebrafish as a model for human cardiac hypertrophy and diastolic dysfunction

Sat, 01 Aug 2015 15:11:11 GMT

title: Inactivation of myosin binding protein C homolog in zebrafish as a model for human cardiac hypertrophy and diastolic dysfunction

蛋白質純化方法

Thu, 11 Dec 2014 08:59:28 GMT

title: 蛋白質純化方法 abstract: 本發明係提供一種蛋白質純化方法，其包括下列步驟：以一第一流向將含蛋白質樣品裝載入一含有離子交換劑之管柱內，令蛋白質得以吸附於該離子交換劑上；以及使用一鹽類溶液以一與第一流向相反之第二流向，沖提吸附有蛋白質之離子交換劑，藉以取得一標的蛋白質，其中樣品與用以沖提吸附於該離子交換劑上之蛋白質的鹽類溶液係以一相反的方向導入管柱內。本發明之方法經證實具有將所沖提出的標的蛋白質的同質性提高，藉以可於無需合併其他純化方法之情況下，即可大幅增加分離的蛋白質濃度，而達到方便、迅速且經濟的純化蛋白質之目的。
description: 專利類型：發明

蛋白質純化方法

Thu, 11 Dec 2014 08:57:37 GMT

title: 蛋白質純化方法 abstract: A method is provided for purifying protein having steps of loading a sample containing proteins into a column containing an ion exchanger in a first direction to allow the ion exchanger to absorb proteins; and passing a salt solution through the column in a second direction opposite to the first direction to elute a target protein from the ion exchanger. The method is proven as capable of improving homogeneity of eluted target protein without combining minute and complicated techniques for protein purification. Therefore, the method is convenient, efficient and economic for purifying proteins.
description: Patent No.: US 8,354,511 B2

An emerging model for nephrotoxicity assessment of xenobiotics

Mon, 29 Sep 2014 05:59:54 GMT

title: An emerging model for nephrotoxicity assessment of xenobiotics

Safety assessments of chalcone derivatives in a zebrafish model

Mon, 29 Sep 2014 05:56:21 GMT

title: Safety assessments of chalcone derivatives in a zebrafish model

Production, purification and characterisation of a chitosanase from Bacillus cereus

Tue, 18 Mar 2014 08:19:30 GMT

title: Production, purification and characterisation of a chitosanase from Bacillus cereus abstract: In the present work, a chitosanase was induced from a squid pen powder-containing Bacillus cereus TKU031 medium, and the addition of 0.05 % (w/v) boric acid or sodium tetraborate resulted in 195 and 177 % enhancement, respectively, in TKU031 chitosanase production. The purified TKU031 chitosanase exhibited optimum activity at pH 5 and 50 °C and was stable at pH 5–9 and <50 °C. The TKU031 chitosanase that was used for chitooligomers preparation was studied. The enzyme products revealed various chitooligomers with different degrees of polymerisation from 3 to 8, as determined by a MALDI-TOF–mass spectrometer, confirming the endo-type nature of the TKU031 chitosanase.

Toxicity assessments of chalcone and some synthetic chalcone analogues in a zebrafish model

Thu, 13 Mar 2014 04:02:37 GMT

title: Toxicity assessments of chalcone and some synthetic chalcone analogues in a zebrafish model abstract: The aim of this study was to investigate the in vivo toxicities of some novel synthetic chalcones. Chalcone and four chalcone analogues 1a–d were evaluated using zebrafish embryos following antibody staining to visualize their morphological changes and muscle fiber alignment. Results showed that embryos treated with 3'-hydroxychalcone (compound 1b) displayed a high percentage of muscle defects (96.6%), especially myofibril misalignment. Ultrastructural analysis revealed that compound 1b-treated embryos displayed many muscle defect phenotypes, including breakage and collapse of myofibrils, reduced cell numbers, and disorganized thick (myosin) and thin (actin) filaments. Taken together, our results provide in vivo evidence of the myotoxic effects of the synthesized chalcone analogues on developing zebrafish embryos.

纖維素分解酶生產菌Streptomyces actuosusA-151之培養基探討

Thu, 11 Jul 2013 03:29:16 GMT

title: 纖維素分解酶生產菌Streptomyces actuosusA-151之培養基探討

Expression, purification and DNA-binding activity of tilapia muscle-specific transcription factor, MyoD, produced in Escherichia coli

Thu, 13 Jun 2013 03:24:03 GMT

title: Expression, purification and DNA-binding activity of tilapia muscle-specific transcription factor, MyoD, produced in Escherichia coli abstract: MyoD is one of several helix-loop-helix proteins regulating muscle-specific gene expression. Using a reverse transcription-polymerase chain reaction, 5′-rapid cDNA end amplification, and plaque hybridization, MyoD cDNA was cloned from the mRNA of tilapia dorsal skeletal muscle. The 1015 bp MyoD cDNA product contained an 846 bp open reading frame with flanking regions of 115 and 64 bp at the 5′- and 3′-ends, respectively. Results showed that the tilapia MyoD sequence, which includes one polypeptide of 281 amino acids, shared sequence identities of 64.3, 64.1, 62.6 and 62.4% with those of zebrafish, carp, and two rainbow trout, respectively. Results from a molecular phylogenic tree assay showed that the tilapia MyoD was more closely related to those of other fishes than of higher vertebrates. Using Escherichia coli, a pET expression system, and an Ni2+-NTA column, we purified ∼35 kDa recombinant tilapia MyoD. Results from an electrophoretic mobility shift assay demonstrated that the purified E. coli-produced tilapia MyoD was capable of binding to the DNA fragment sequence CA(C/T)(C/A)TG. © 2002 Elsevier Science Inc. All rights reserved.

Erratum to ''Expression, purification and DNA-binding activity oftilapia muscle-specific transcription factor, MyoD, produced inEscherichia coli''

Thu, 13 Jun 2013 03:23:56 GMT

title: Erratum to ''Expression, purification and DNA-binding activity oftilapia muscle-specific transcription factor, MyoD, produced inEscherichia coli'' abstract: For a better understanding of the hyperlipidemic function of saturated fat, we have studied the comparative effects of diet supplementation with 10 and 20% coconut oil on the main lipid classes of chick plasma. Changes in fatty acid composition of free fatty acid and triglyceride fractions were parallel to that of the experimental diet. Thus, the increase in the percentages of 12:0 and 14:0 acids may contribute to the hypercholesterolemic effects of coconut oil feeding. Plasma phospholipids incorporated low levels of 12:0 and 14:0 acids whereas 18:0, the main saturated fatty acid of this fraction, also increased after coconut oil feeding. The percentage of 20:4 n-6 was higher in plasma phospholipids than in the other fractions and was significantly decreased by our dietary manipulations. Likewise, minor increases were found in the percentages of 12:0 and 14:0 acids in plasma cholesterol esters. However, the percentage of 18:2 acid significantly increased after coconut oil feeding. Our results show a relationship between fatty acid composition of diets and those of plasma free fatty acid and triglyceride fractions, whereas phospholipids and cholesterol esters are less sensitive to dietary changes.

Treatment with sodium benzoate leads to malformation of zebrafish larvae

Fri, 07 Jun 2013 02:32:04 GMT

title: Treatment with sodium benzoate leads to malformation of zebrafish larvae abstract: Sodium benzoate (SB) is a commonly used food preservative and anti-microbial agent in many foods from soup to cereals. However, little is known about the SB-induced toxicity and teratogenicity during early embryonic development. Here, we used zebrafish as a model to test the toxicity and teratogenicity because of their transparent eggs; therefore, the organogenesis of zebrafish embryos is easy to observe. After low dosages of SB (1-1000 ppm) treatment, the zebrafish embryos exhibited a 100% survival rate. As the exposure dosages increased, the survival rates decreased. No embryos survived after treatment with 2000 ppm SB. The 50% lethal dose (LD(50)) of zebrafish is found to be in the range of 1400-1500 ppm. Gut abnormalities, malformation of pronephros, defective hatching gland and edema in pericardial sac were observed after treatment with SB. Compared to untreated littermates (vehicle-treated control), SB-treated embryos exhibited significantly reduced tactile sensitivity frequencies of touch-induced movement (vehicle-treated control: 27.60+/-1.98 v.s. 1000 ppm SB: 7.89+/-5.28; N=30). Subtle changes are easily observed by staining with specific monoclonal antibodies F59, Znp1 and alpha6F to detect morphology changes in muscle fibers, motor axons and pronephros, respectively. Our data showed that the treatment of SB led to misalignment of muscle fibers, motor neuron innervations, excess acetyl-choline receptor cluster and defective pronephric tubes. On the basis of these observations, we suggest that sodium benzoate is able to induce neurotoxicity and nephrotoxicity of zebrafish larvae.

Purification and some properties of three xylanases from Aspergillus aculeatus F-50

Fri, 31 May 2013 03:34:00 GMT

title: Purification and some properties of three xylanases from Aspergillus aculeatus F-50 abstract: Three distinct extracellular xylanases (FIa-, FIb-, and FIII-xylanases) from a culture filtrate of Aspergillus aculeatus No. F-50 were purified to homogeneity by SDS polyacrylamide gel electrophoresis. The molecular weights of FIa-, FIb-, and FIII-xylanases were estimated to be 18,000, 26,000, and 52,000, and their pI values were pH 5.6, 9.0, and 3.8, respectively. The pH optima of xylanase activities were from 4.5 to 5.0. The optimum temperatures for enzyme activities were from 50℃ to 70℃. All three xylanases were highly specific for xylan hydrolysis, and they did not cleave xylobiose.

Purification and characterization of two bifunctional chitinases/lysozymes extracellularly produced by Pseudomonas aeruginosa K-187 in a shrimp and crab shell powder medium

Fri, 31 May 2013 03:33:54 GMT

title: Purification and characterization of two bifunctional chitinases/lysozymes extracellularly produced by Pseudomonas aeruginosa K-187 in a shrimp and crab shell powder medium abstract: Two extracellular chitinases (FI and FII) were purified from the culture supernatant of Pseudomonas aeruginosa K-187. The molecular weights of FI and FII were 30,000 and 32,000, respectively, by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and 60,000 and 30,000, respectively, by gel filtration. The pIs for FI and FII were 5.2 and 4.8, respectively. The optimum pH, optimum temperature, pH stability, and thermal stability of FI were pH 8, 50 degrees C, pH 6 to 9, and 50 degrees C; those of FII were pH 7, 40 degrees C, pH 5 to 10, and 60 degrees C. The activities of both enzymes were activated by Cu2+; strongly inhibited by Mn2+, Mg2+, and Zn2+; and completely inhibited by glutathione, dithiothreitol, and 2-mercaptoethanol. Both chitinases showed lysozyme activity. The purified enzymes had antibacterial and cell lysis activities with many kinds of bacteria. This is the first report of a bifunctional chitinase/lysozyme from a prokaryote.

Human aldehyde dehydrogenase E3 isozyme: The N-terminal primary structure

Fri, 31 May 2013 03:33:50 GMT

title: Human aldehyde dehydrogenase E3 isozyme: The N-terminal primary structure

Inhibition of Lysozyme Activity by Acidic Polymers

Fri, 31 May 2013 03:33:44 GMT

title: Inhibition of Lysozyme Activity by Acidic Polymers

Ethanol fermentation in a tower fermenter using self-aggregatingSaccharomyces uvarum

Fri, 31 May 2013 03:33:34 GMT

title: Ethanol fermentation in a tower fermenter using self-aggregatingSaccharomyces uvarum abstract: A self-aggregating strain ofSaccharomyces uvarum (U4) was used as a biocatalyst to carry out continuous ethanol fermentation in a tower fermentor equipped with a cell separator. Cell aggregates (2–3 mm) formed a stable packed bed in the fermentor, and the cell separator retained yeast cells effectively. Corn steep liquor was used as a nitrogen source for the fermentation of corn syrup and black strap molasses. An ethanol productivity of 54 g/L/h was reached using corn syrup at a dilution rate of 0.7/h, and sugar concentration in the feed was 15% (w/v). For molasses fermentation, an ethanol productivity of 22 g/L/h was obtained at a dilution rate of 0.7/h, and sugar concentration in the feed was 12.5% (w/v). Ethanol yields obtained from tower fermentation are higher than those obtained from flask fermentation (96% for corn syrup fermentation and 92% for molasses fermentation). No significant loss in fermentation activity was observed after 3 mo of operation.

Evidence for mitochondrial localization of betaine aldehyde dehydrogenase in rat liver - purification, characterization and comparison with human cytoplasmic E3 isozyme

Fri, 31 May 2013 03:33:29 GMT

title: Evidence for mitochondrial localization of betaine aldehyde dehydrogenase in rat liver - purification, characterization and comparison with human cytoplasmic E3 isozyme abstract: Betaine aldehyde dehydrogenase has been purified to homogeneity from rat liver mitochondria. The properties of betaine aldehyde dehydrogenase were similar to those of human cytoplasmic E3 isozyme in substrate specificity and kinetic constants for substrates. The primary structure of four tryptic peptides was also similar; only two substitutions, at most, per peptide were observed. Thus, betaine aldehyde dehydrogenase is not a specific enzyme, as formerly believed; activity with betaine aldehyde is a property of aldehyde dehydrogenase (EC 1.2.1.3), which has broad substrate specificity. Up to the present time the enzyme was thought to be cytoplasmic in mammals. This report establishes, for the first time, mitochondrial subcellular localization for aldehyde dehydrogenase, which dehydrogenates betaine aldehyde, and its colocalization with choline dehydrogenase. Betaine aldehyde dehydrogenation is an important function in the metabolism of choline to betaine, a major osmolyte. Betaine is also important in mammalian organisms as a major methyl group donor and nitrogen source. This is the first purification and characterization of mitochondrial betaine aldehyde dehydrogenase from any mammalian species.

Human aldehyde dehydrogenase E3 isozyme is a betaine aldehyde dehydrogenase

Fri, 31 May 2013 03:33:25 GMT

title: Human aldehyde dehydrogenase E3 isozyme is a betaine aldehyde dehydrogenase abstract: The E3 isozyme of human aldehyde dehydrogenase (EC 1.2.1.3), with broad substrate specificity, which also catalyzes dehydrogenation of 4-aminobutyraldehyde, was purified and sequenced recently (1,3). It has been shown during this investigation to have betaine aldehyde dehydrogenase activity. Betaine aldehyde and 4-aminobutyraldehyde activities copurified on six chromatographic columns. Molecular properties of the homogeneous product were identical with those of E3 isozyme. Activity with betaine aldehyde was considerably higher than that with 4-aminobutyraldehyde, the best known substrate. Thus, human E3 isozyme and betaine aldehyde dehydrogenase (EC 1.2.1.8) are the same enzyme.

Betaine aldehyde dehydrogenase from rat liver mitochondrial matrix

Fri, 31 May 2013 03:33:20 GMT

title: Betaine aldehyde dehydrogenase from rat liver mitochondrial matrix abstract: An NAD-linked aldehyde dehydrogenase which in addition to aliphatic and aromatic aldehydes, metabolizes aminoaldehydes and betaine aldehyde, has been purified to homogeneity from male Sprague–Dawley rat liver mitochondria. The properties of the rat mitochondrial enzyme are similar to those of a rat liver cytoplasmic betaine aldehyde dehydrognase and the human cytoplasmic E3 isozyme. The primary structure. of four tryptic peptides were also similar; only one difference in primary structure was observed. The close similarity of properties of the cytoplasmic with the mitochondrial form suggest that the cytoplasmic and mitochondrial betaine aldehyde dehydrogenase may be coded for by the same nuclear gene. Investigation of the mitochondrial form by isoelectric focusing resulted in visualization of multiple forms, different from those seen in the cytoplasm suggesting that the enzyme may be processed in the mitochondria.

Betaine aldehyde, betaine, and choline levels in rat liver during ethanol metabolism

Fri, 31 May 2013 03:33:12 GMT

title: Betaine aldehyde, betaine, and choline levels in rat liver during ethanol metabolism abstract: Betaine aldehyde levels were determined in rat livers following 4 weeks of ethanol feeding, employing the Lieber-De Carli liquid diet. The results showed that the levels of betaine aldehyde are unaffected by alcohol feeding to rats. These levels in both experimental and control animals were found to be quite low, 5.5 nmol/g liver. Betaine aldehyde levels have not been determined previously in mammalian liver because of methodological difficulties. This investigation employed fast atom bombardment-mass spectroscopy to determine the levels of betaine aldehyde, betaine, and choline. The decrease in betaine levels following ethanol administration confirmed the results of other investigators. Choline levels determined during this investigation were lower than previously reported. The reason for starting this investigation was the fact that the enzyme that catalyzes betaine aldehyde dehydrogenation to betaine, which is distributed in both mitochondria and the cytoplasm, was found to also metabolize acetaldehyde with K(m) and V(max) values lower than those for betaine aldehyde. Thus, it appeared likely that the metabolism of acetaldehyde during ethanol metabolism might inhibit betaine aldehyde conversion to betaine and thereby result in decreased betaine levels (Barak et al., Alcohol 13: 395-398, 1996). The fact that betaine aldehyde levels in alcohol-fed animals were similar to those in controls demonstrates that competition between acetaldehyde and betaine aldehyde for the same enzyme does not occur. This complete lack of competition suggests that betaine aldehyde dehydrogenase in the mitochondrial matrix may totally metabolize betaine aldehyde to betaine without any involvement of cytoplasmic betaine aldehyde dehydrogenase.

Cellulase and xylanase production byAspergillus sp. G-393

Fri, 31 May 2013 03:33:05 GMT

title: Cellulase and xylanase production byAspergillus sp. G-393

Bioconversion of Shrimp Shell Wastes for Protease Production by a Newly Isolated Strain Chryseobacterium Taeanense TKU001

Tue, 09 Apr 2013 03:39:27 GMT

title: Bioconversion of Shrimp Shell Wastes for Protease Production by a Newly Isolated Strain Chryseobacterium Taeanense TKU001 abstract: An extracellular metalloprotease with novel properties of solvent- and surfactant-stable was purified from the culture supernatant of Chryseobacterium taeanense TKU001 with shrimp shell wastes as the sole carbon/nitrogen source. Two extracellular proteases (FI and FII) were purified and characterized, and their molecular weights, pH and thermal stabilities were determined. The molecular masses of TKU001 protease FI and FII determined by SDS-PAGE and gel filtration were approximately 41 kDa and 75 kDa, respectively. TKU001 protease FI and FII were both inhibited completely by EDTA, indicating that the TKU001 protease FI and FII were metalloproteases. TKU001 protease FI and FII retained more than 75% of its original protease activity after preincubation for 10 days at 4.degree.C in the presence of 25% most tested organic solvents. The novelties of the TKU001 protease include its high stability to the solvents and surfactants. These unique properties make it an ideal choice for application in detergent formulations and enzymatic peptide synthesis.

Bioconversion of Shellfish Chitin Wastes for the Production of Bacillus subtilis W-118 Chitinase

Tue, 09 Apr 2013 03:39:24 GMT

title: Bioconversion of Shellfish Chitin Wastes for the Production of Bacillus subtilis W-118 Chitinase abstract: Bacillus subtilis W-118, an antifungal materials producing strain, excreted one chitinase when cultured in a medium containing shrimp and crab shell powder as major carbon source. The chitinase, purified by sequential chromatography, had a molecular mass of 20,600 and pI of 6. The optimum pH, optimum temperature, and pH stability of the chitinase were pH 6, 37.degree.C, and pH 5-7, respectively. The unique characteristics of the purified chitinase include low molecular mass and acidic pI. In the investigation of the inhibitory activity, it was found that the growth of F. oxysporum was 100% inhibited after incubation for 1 day with sterilized W-118 chitinase solution (5.6 units/mL).The chitinase hydrolyzates of chitin with low degrees of polymerization (DP) from 1 to 6 were analyzed by HPLC. Longer reaction time led to the generation of chitin oligosaccharides with lower DP. The chitin oligosaccharides were examined for their inhibitory effects on Fusarium oxysporum and human leukemia cell lines.

鳳梨酵素所含蛋白脢及幾丁質脢之純化與定性

Tue, 09 Apr 2013 03:39:20 GMT

title: 鳳梨酵素所含蛋白脢及幾丁質脢之純化與定性 abstract: 鳳梨酵素(Bromelain)是由鳳梨莖所提煉的一種半胱胺酸型蛋白質水解酵素，其粗酵素製品對幾丁聚醣有頗強之水解能力。雖然鳳梨酵素已被證實具有促進抗炎、消腫作用，是一種天然的抗炎蛋白質水解酵素；但針對其抗炎機制是由鳳梨酵素所含何種蛋白水解酵素所作用，至今甚少有所研究，故本實驗主要探討由鳳梨酵素所純化分離之幾丁質脢與蛋白質脢其生化特性。將粗酵素液經離子交換層析及膠體過濾層析結果發現，鳳梨酵素中至少含有二種蛋白質脢(I-2、IV)、二種幾丁質脢(I-1、III)和一個兼具蛋白質脢和幾丁質脢(II)的酵素。利用SDS-PAGE分析，可獲得五種酵素的分子量(I-1、I-2、II、III、IV)分別為26KDa、26KDa、28KDa、28KDa 以及26KDa。

TKU001 Strain所產生蛋白脢之純化與定性

Tue, 09 Apr 2013 03:39:17 GMT

title: TKU001 Strain所產生蛋白脢之純化與定性 abstract: 此菌株是經由水解真菌細胞壁所篩選出之TKU001菌株，而本實驗以發酵蝦殼粉(shrimp shell powder；簡稱SSP)作為主要營養源，探討TKU001所生產蛋白脢之純化分離及定性。最適培養條件為0.5％SSP、0.1％K2HPO4、0.05％MgSO47H2O之50mL液態培養基(pH 6)於250mL之三角錐形瓶中，以37℃振盪(150rpm)培養3天後，可得最大之蛋白脢活性(0.11U/mL)。利用TKU001之蛋白脢較適生產條件大量培養，所得發酵液經DEAE Sepharose CL-6B、Sephacryl S-200等蛋白質分離純化步驟，可純化出二種蛋白脢F1&F2)。蛋白(之生化特性經分析結果：F1蛋白脢最適反應溫度為60℃、最適反應pH 8、熱安定性<60℃、pH安定性6~9；F2蛋白脢最適反應溫度為60℃、最適反應pH 7、熱安定性<50℃、pH安定性7~9。抑制劑及金屬離子對酵素活性的影響，分別受到濃度(5mM)EDTA和Fe/sup 2+/、Cu/sup 2+/、Mn/sup 2+/離子的抑制，但F2蛋白脢不受Mn/sup 2+/離子的抑制。

Purification and Characterization of Chitinases and Proteases from Papain

Tue, 09 Apr 2013 03:39:14 GMT

title: Purification and Characterization of Chitinases and Proteases from Papain

Purification and Characterization of Chitinases and Proteases from Papain

Tue, 09 Apr 2013 03:39:10 GMT

title: Purification and Characterization of Chitinases and Proteases from Papain

Bacillus subtilis TKU007利用蝦殼廢棄物發酵所產耐介面活性劑及有機溶劑之鹼性蛋白脢其純化及定性

Tue, 09 Apr 2013 03:39:07 GMT

title: Bacillus subtilis TKU007利用蝦殼廢棄物發酵所產耐介面活性劑及有機溶劑之鹼性蛋白脢其純化及定性 abstract: An extracellular serine protease with novel properties of surfactant-stable, solvent-stable, and alkaliphilic was purified from the culture supernatant of Bacillus subtilis TKU007 with shrimp shell wastes as the sole carbon/nitrogen source. The TKU007 protease showed suppressing effect on the chitosanase, which appeared at the first day. The molecular mass of TKU007 protease determined by SDS-PAGE and gel filtration was approximately 28 kDa and 30 kDa, respectively. The optimum pH, optimum temperature, pH stability, thermal stability, Km, and Vmax of TKU007 protease was 7-11, 50.degree.C, pH 5-11, 50.degree.C, 0.13 mg/mL, and 0.86 U/mL, respectively. More than 80% of its original activity was retained even after preincubation for 10 days at 25.degree.C in the presence of 25% tested organic solvents. Additionally, the TKU007 protease retained 100%, 100%, 50%, and 65% of its original activity in the presence of 2% Tween 20, 2% Tween 40, 2% Triton X-100, or 0.5 mM SDS, respectively. In conclusion, the novelties of the TKU007 protease include its high stability to the solvents, surfactants, and alkali. These unique properties make it an ideal choice for application in detergent formulations and enzymatic peptide synthesis.

Bacillus cereus TKU006所生產幾丁質脢及蛋白脢之純化與定性

Tue, 09 Apr 2013 03:39:03 GMT

title: Bacillus cereus TKU006所生產幾丁質脢及蛋白脢之純化與定性 abstract: 本實驗由台灣北部土壤所篩選出之箘株Bacillus cereus，以自製之蝦頭粉(shrimp shell powder；簡稱SSP)作為菌生產蛋白脢和幾丁質脢之主要營養源。探討其培養時碳源、碳源濃度、培養時間、培養溫度、培養pH值等。Bacillus cereus生產蛋白脢和幾丁質脢之最適培養條件為2%SSP、0.1%K2HPO4、0.05%MgSO4,7H2O，在25℃、pH7之25mL液體培養基，於250mL的三角錐型瓶中震盪培養3天，得最大之蛋白脢和幾丁質脢活性。Bacillus cereus發酵液經硫銨沉澱、DEAE Sepharose、CM Sepharose、Sephadex S-200和Sephadex S-100可分離純化出蛋白脢和幾丁質脢。蛋白脢在Sephadex S-100純化後，幾以失活。蛋白質脢(純化前)最適反應溫度與pH為50℃、9.0；穩定性方面，溫度與PH分別在25~60℃與pH 3~11。幾丁質脢最適反應溫度與pH為40℃、5.0；穩定性方面，溫度與PH分別在25~60℃與pH 3~11。抑制劑及金屬離子對幾丁質脢活性的影響，受到Fe/sup 2+/的抑制。有機溶劑對幾丁質脢活性的影響，在丙酮及DMF下完全抑制。

The Antitumor Activity of the Hydrolysates of Chitinous Materials Hydrolyzed by Crude Enzyme from Bacillus amyloliquefaciens V656

Tue, 09 Apr 2013 03:38:59 GMT

title: The Antitumor Activity of the Hydrolysates of Chitinous Materials Hydrolyzed by Crude Enzyme from Bacillus amyloliquefaciens V656 abstract: Chitin, colloidal chitin and water-soluble chitosan were hydrolyzed by crude enzyme solution produce by Bacillus amyloliquefaciens V656. The hydrolysates with 12 h hydrolysis contained optimal (GlcNAc)6 and showed higher antitumor activity. Among those chitinous materials, the most effective one was the hydrolysates of water-soluble chitosan, which inhibited the growth of CT26 cells and reduced the survival rate to 34% in 1 day. Since the hydrolysate of water-soluble chitosan contained the optimal hexamer/(GlcNAc)6 at 12 h, it is conjectured that the antitumor activity should be related to (GlcNAc)6. This conjecture was further affirmed by experiment with pure (GlcNAc)6. However, This phenomenon might be due to the synergistic effect of the oligomers (GlcNAc)n, n = 1Ã¢ÂÂ6 in the hydrolysates. The antitumor effect of the chitinous hydrolysates is worth further investigation. The aim of this study was to investigate the induced apoptosis in CT26 cells by the hydrolysates of chitinous materials. It was found that the hydrolysates (A, B and C) inhibited the survival of CT26 cells in a concentrationand time-dependent manner. The hydrolysates induced characteristic DNA fragmentation of the CT26 cells. These results suggested that the hydrolysates from chitinous materials are potent apoptosisinducing agents for CT26 cells.

Reclamation of Chitinous Materials by Bromelain for the Preparation of Antitumor and Antifungal Materials

Tue, 09 Apr 2013 03:38:55 GMT

title: Reclamation of Chitinous Materials by Bromelain for the Preparation of Antitumor and Antifungal Materials abstract: The main purpose of this research was to investigate the antitumor and antimicrobial activities of the chitooligosaccharides containing hydrolyzates obtained from the hydrolysis of chitinous materials (such as chitin, chitosan, and squid pen) by bromelain. The optimum preparations were gained in the hydrolysates of squid pen powder hydrolyzed at pH5, 37.degree.C for 2 days by 0.1% bromelain. The hydrolysates had an 80% inhibitory activity on Fusarium oxysporum. Chitooligosaccharides were recovered from the hydrolysates and were used for tumor cell surviving test. Surviving rate of the human leukemic U937 cells was reduced to 69% by the chitooligosaccharides.

Production of a Protease by Monascus Purpureus Crc31499 in a Shrimp and Crab Shell Powder Medium

Tue, 09 Apr 2013 03:38:50 GMT

title: Production of a Protease by Monascus Purpureus Crc31499 in a Shrimp and Crab Shell Powder Medium abstract: Monascus purpureus CCRC31499 produced a protease when it was grown in a medium containing shrimp and crab shell powder (SCSP) of marine wastes. An extracellular protease was purified from the culture supernatant to homology. The protease had a molecular weight of 40,000 and a pI of 7.9. The optimal pH, optimum temperature, pH stability, and thermal stability of the protease were pH 7-9, 40.degree.C, pH 5-9, and 40.degree.C, respectively. This is also the first report of isolation of a protease from Monascus species.

Prevalence and antibiotic resistance of Listeria species in food products in Taipei, Taiwan

Wed, 20 Mar 2013 03:10:02 GMT

title: Prevalence and antibiotic resistance of Listeria species in food products in Taipei, Taiwan abstract: A total of 400 samples including meat products, dairy and dairy products, fresh vegetables, fresh seafood, and ready-to-eat food products from supermarkets in Taipei area were collected and analyzed for the prevalence of Listeria species. The overall occurrence of Listeria spp. was 16.5%, and most of them were isolated from meat products and vegetables. Listeria monocytogenes was isolated from 22 out of the 400 (5.5%) samples studied. Other species found were Listeria innocua (7.5%), Listeria ivanovii (1%), Listeria seeligeri (0.5%), Listeria grayi (0.5%) and Listeria welshimeri (1.5%). The possibility of antibiotic resistance of the 66 isolated Listeria spp. was also examined by the standard disk diffusion method. L. monocytogenes strains isolated from food sample were treated with 8 antibiotics currently used in human or domestic animal therapy. Considering the fact that L. monocytogenes is slowly becoming antibiotic resistant, a continuous examination of emerging antimicrobial resistance of this pathogen is important to ensure effective treatment of human listeriosis. Overall, Listeria spp. was resistant to penicillin (7.58%), chloramphenicol (3.7%) and tetracycline (1.96%), but sensitive to amoxicillin, vancomycin, ampicillin, rifampicin and sulfamethoxazole. The results in this study are helpful in enriching the data on antibiotic resistance of strains isolated from food and in developing effective risk management strategies.

Conversion of shrimp shell by using Serratia sp. TKU017 fermentation for the production of enzymes and antioxidants

Wed, 27 Feb 2013 01:39:59 GMT

title: Conversion of shrimp shell by using Serratia sp. TKU017 fermentation for the production of enzymes and antioxidants abstract: A chitinase (CHT), and a protease (PRO) were purified from the culture supernatant of Serratia sp. TKU017 with shrimp shell as the sole carbon/nitrogen source. The molecular masses of CHT and PRO determined by SDS-PAGE were approximately 65 kDa and 53 kDa, respectively. CHT was inhibited by Mn2+, Cu2+ and PRO was inhibited by most tested divalent metals, EDTA. The optimum pH, optimum temperature, pH stability, and thermal stability of CHT and PRO were (pH 5, 50°C, pH 5–7, ＜50°C) and (pH 9, 40°C, pH 5–11, ＜40°C), respectively. PRO retained 95% of its protease activity in the presence of 0.5 mM SDS. The result demonstrates that PRO is SDS-resistant protease and probably has a rigid structure. The 4th day supernatant showed the strongest antioxidant activity (70%, DPPH scavenging ability) and the highest total phenolic content (196±6.2 μg of gallic acid equival/mL). Significant associations between the antioxidant potency and the total phenolic content, as well as between the antioxidant potency and free amino groups, were found for the supernatant. With this method, we have shown that shrimp shell wastes can be utilized and it’s effective in the production of enzymes and antioxidants, facilitating its potential use in industrial applications and functional foods.

Purification and characterization of chitinases and chitosanases from a new species strain Pseudomonas sp. TKU015 using shrimp shells as a substrate

Wed, 27 Feb 2013 01:39:55 GMT

title: Purification and characterization of chitinases and chitosanases from a new species strain Pseudomonas sp. TKU015 using shrimp shells as a substrate abstract: A chitinase (CHT1) and a chitosanase (CHS1) were purified from the culture supernatant of Pseudomonas sp. TKU015 with shrimp shell wastes as the sole carbon and nitrogen source. The optimized conditions of this new species strain (Gen Bank Accession Number EU103629) for the production of chitinases were found to be when the culture was shaken at 30 °C for 3 days in 100 mL of medium (pH 8) containing 0.5% shrimp shell powder (SSP) (w/v), 0.1% K2HPO4, and 0.05% MgSO4·7H2O. The molecular weights of CHT1 and CHS1 determined by SDS–PAGE were approximately 68 kDa and 30 kDa, respectively. The optimum pH, optimum temperature, pH stability, and the thermal stability of CHT1 and CHS1 were pH 6, 50 °C, pH 5–7, <50 °C and pH 4, 50 °C, pH 3–9, <50 °C, respectively. CHT1 was inhibited completely by Mn2+ and Fe2+, and CHS1 was inhibited by Mn2+, Cu2+, and PMSF. CHT1 was only specific to chitin substrates, whereas the relative activity of CHS1 increased when the degree of deacetylation of soluble chitosan increased.

Purification and characterization of a protease extracellularly produced by Monascus purpureus CCRC31499 in a shrimp and crab shell powder medium

Wed, 27 Feb 2013 01:39:51 GMT

title: Purification and characterization of a protease extracellularly produced by Monascus purpureus CCRC31499 in a shrimp and crab shell powder medium abstract: Monascus purpureus CCRC31499 produced a protease when it was grown in a medium containing shrimp and crab shell powder (SCSP) of marine wastes. An extracellular protease was purified from the culture supernatant to homology. The protease had a molecular weight of 40,000 and a pI of 7.9. The optimal pH, optimum temperature, pH stability, and thermal stability of the protease were pH 7–9, 40 °C, pH 5–9, and 40 °C, respectively. In addition to protease activity, CCRC31499 also exhibited activity of enhancing vegetable growth in culture supernatant. This is also the first report of isolation of a protease from Monascus species.