Abstract:
:A novel automated image analysis method is described for characterizing the viability and morphology of animal cells from suspension cultures. With the aid of the exclusion dye Trypan Blue, the total and viable cell counts and the percentage of dead cells present are found. The area, perimeter, equivalent diameter, and circularity of the projected image of each cell are also measured, allowing the estimation of cell volume. The image analysis method is inherently sensitive, precise, consistent (non-operator dependent) and relatively fast, taking approximately 22 min to analyze one sample. The data it gives on individual cellular activity, as characterized by Trypan Blue uptake and cell morphology, are valuable in allowing early diagnosis of even subtle changes in the health of a culture. The method should permit better optimization of culture conditions, and will provide data for the modeling of cell population dynamics. As the conventional manual method is operator dependent, relatively limited in the amount of information it provides, and has a tendency to underestimate Trypan Blue takeup, it is suggested that image analysis be the preferred option for animal cell counting and viability determinations.
journal_name
Enzyme Microb Technoljournal_title
Enzyme and microbial technologyauthors
Tucker KG,Chalder S,al-Rubeai M,Thomas CRdoi
10.1016/0141-0229(94)90106-6subject
Has Abstractpub_date
1994-01-01 00:00:00pages
29-35issue
1eissn
0141-0229issn
1879-0909pii
0141-0229(94)90106-6journal_volume
16pub_type
杂志文章abstract::Two acidic β-glucosidases (βGI and βGII) from the brown rot fungus Fomitopsis palustris were purified to homogeneity by several chromatographic steps. βGI and βGII had molecular weights of 130 and 213 kDa, respectively, and exhibited optimum activity at pH 2.5 and 55°C. The K(m) values of βGI and βGII for p-nitropheny...
journal_title:Enzyme and microbial technology
pub_type: 杂志文章
doi:10.1016/j.enzmictec.2010.12.012
更新日期:2011-04-07 00:00:00
abstract::The methyl ester of 2-benzoxazolon-3-yl-acetic acid was used as an acyl donor in the penicillin amidase-catalysed transfer reaction to 7-aminodesacetoxycephalosporanic acid. The synthesis of 7-(2-benzoxazolon-3-yl-acetamido)-desacetoxycephalosporanic acid was carried out as a kinetically controlled reaction. A charact...
journal_title:Enzyme and microbial technology
pub_type: 杂志文章
doi:10.1016/0141-0229(92)90144-d
更新日期:1992-06-01 00:00:00
abstract::In our previous study, we produced α-keto acids by using an L-amino acid deaminase PmiLAAD (wide-type) from Proteus mirabilis, however, the catalytic efficiency was low due to its low substrate affinity. In this study, protein engineering of PmiLAAD was performed to improve the α-keto acid production. PmiLAAD was engi...
journal_title:Enzyme and microbial technology
pub_type: 杂志文章
doi:10.1016/j.enzmictec.2019.109393
更新日期:2020-01-01 00:00:00
abstract::Enzymatic production of cephalexin using immobilized penicillin G acylase was studied. The factors that affect the conversion of 7-amino-3-deacetoxycephalosporanic acid (7-ADCA) to cephalexin, such as pH; temperature; concentrations of 7-ADCA, D(-)-phenylglycine methyl ester (PGME), and immobilized penicillin G acylas...
journal_title:Enzyme and microbial technology
pub_type: 杂志文章
doi:10.1016/0141-0229(94)90095-7
更新日期:1994-08-01 00:00:00
abstract::Solid-liquid enzyme reactions constitute important processes in biochemical industries. The isomerization of d-glucose to d-fructose, using the immobilized glucose isomerase (Sweetzyme T), as a typical example of solid-liquid catalyzed reactions has been carried out in one stage and multi-stage novel type of impinging...
journal_title:Enzyme and microbial technology
pub_type: 杂志文章
doi:10.1016/j.enzmictec.2013.11.006
更新日期:2014-02-05 00:00:00
abstract::Cystathionine γ-lyase (CGL) is a key enzyme in the methionine-cysteine cycle in all living organisms forming cysteine, α-ketobutyrate and ammonia via homocysteine and cystathionine intermediates. Although, human and plant CGLs have been extensively studied at the molecular and mechanistic levels, there has been little...
journal_title:Enzyme and microbial technology
pub_type: 杂志文章
doi:10.1016/j.enzmictec.2015.08.004
更新日期:2015-12-01 00:00:00
abstract::The xylanase R8 gene (xynR8) from uncultured rumen fungi was cloned and successfully expressed in Lactobacillus reuteri. A xylanase activity of 132.1 U/mL was found in the broth of L. reuteri R8, the transformant containing pNZ3004 vector with xynR8 gene insertion. Two distinct forms of recombinant xylanase with diffe...
journal_title:Enzyme and microbial technology
pub_type: 杂志文章
doi:10.1016/j.enzmictec.2014.06.004
更新日期:2014-10-01 00:00:00
abstract::A methyl parathion hydrolase (MPH) gene, bjmpd, was cloned from a newly isolated MP-degrading bacterial strain, Burkholderia jiangsuensis MP-1T and heterologously expressed in Escherichia coli BL21 (DE3). Although the amino acid sequence of the bjmpd-encoded enzyme, named BjMPH, differed from that of MPH from Pseudomo...
journal_title:Enzyme and microbial technology
pub_type: 杂志文章
doi:10.1016/j.enzmictec.2016.07.005
更新日期:2016-11-01 00:00:00
abstract::Biocatalytic peptide synthesis will benefit from enzymes that are active at low water levels in organic solvent compositions that allow good substrate and product solubility. To explore the use of proteases from thermophiles for peptide synthesis under such conditions, putative protease genes of the subtilase class we...
journal_title:Enzyme and microbial technology
pub_type: 杂志文章
doi:10.1016/j.enzmictec.2015.03.003
更新日期:2015-06-01 00:00:00
abstract::We demonstrate the feasibility of growing crystals of protein in volumes as small as 1 nanoliter. Advances in the handling of very small volumes (i.e. through inkjet and other technologies) open the way towards fully automated systems. The rationale for these experiments is the desire to develop a system that speeds u...
journal_title:Enzyme and microbial technology
pub_type: 杂志文章
doi:10.1016/s0141-0229(01)00496-3
更新日期:2002-03-13 00:00:00
abstract::Supercritical fluids offer environmental advantages over chemical solvents, while providing enhanced separation and chemical selectivity. The use of supercritical fluids for the recovery of products from biomass and the transformation of selected molecules (to add value) was studied. Free fatty acids were bio-catalyti...
journal_title:Enzyme and microbial technology
pub_type: 杂志文章
doi:10.1016/j.enzmictec.2011.07.004
更新日期:2011-09-10 00:00:00
abstract::Although the chaperon solvent plug was reported as a strategy to reduce aggregation before the column inlet in SEC (size-exclusion chromatography) protein refolding process, the appropriate position at which sample injected and the volume of the chaperon solvent plug have not been elucidated. Therefore, the detail of ...
journal_title:Enzyme and microbial technology
pub_type: 杂志文章
doi:10.1016/j.enzmictec.2011.05.003
更新日期:2011-07-10 00:00:00
abstract::Human interferon alpha 2b (IFN α2b) is a type I interferon exhibiting antiviral, anti-proliferative and immunomodulatory activities. The clinical outcome of the approved recombinant human IFN α2b drugs in the market suffers from short plasma half-life, rapid clearance and other side effects. Human IFN α2b expression i...
journal_title:Enzyme and microbial technology
pub_type: 杂志文章
doi:10.1016/j.enzmictec.2019.05.007
更新日期:2019-09-01 00:00:00
abstract::Direct esterifications using a nylon-immobilized lipase from Candida cylindracea were carried out in batch and continuous-flow reactors. The immobilized enzyme was effective in catalyzing the synthesis of ethylpropionate, isoamylpropionate, and isoamylbutyrate. With ethanol dissolved in hexane as a substrate, the maxi...
journal_title:Enzyme and microbial technology
pub_type: 杂志文章
doi:10.1016/0141-0229(92)90054-r
更新日期:1992-11-01 00:00:00
abstract::Gamma glutamyl transpeptidase from Bacillus pumilus KS12 (GGTBP) was cloned, expressed in pET-28-E. coli expression system as a heterodimeric enzyme with molecular weights of 45 and 20 kDa for large and small subunit, respectively. It was purified by nickel affinity chromatography with hydrolytic and transpeptidase ac...
journal_title:Enzyme and microbial technology
pub_type: 杂志文章
doi:10.1016/j.enzmictec.2011.08.005
更新日期:2012-03-10 00:00:00
abstract::The effects of biological pretreatment on Pinus radiata and Eucalyptus globulus, were evaluated after exposure to two brown rot fungi Gloephylum trabeum and Laetoporeus sulphureus. Changes in chemical composition, structural modification, and susceptibility to enzymatic hydrolysis in the degraded wood were analyzed. A...
journal_title:Enzyme and microbial technology
pub_type: 杂志文章
doi:10.1016/j.enzmictec.2011.08.004
更新日期:2011-10-10 00:00:00
abstract::In this study, distillery wastewater was treated by dark fermentation or photofermentation alone, and by sequential dark and photofermentation processes using anaerobic saccharolytic consortium and purple nonsulfur bacteria. Combination of dark and photofermentation resulted in the maximal H2 yield of 17.6L/L of disti...
journal_title:Enzyme and microbial technology
pub_type: 杂志文章
doi:10.1016/j.enzmictec.2017.11.009
更新日期:2018-03-01 00:00:00
abstract::Before applying nanotechnologies in biomedical and environmental areas it is advised to study interactions of nanoparticles and other nanomaterials with biomacromolecule present in living system. Moreover there is scarcity of reports on interactions between nanoparticles and biomaterials. In present report a rapid, ec...
journal_title:Enzyme and microbial technology
pub_type: 杂志文章
doi:10.1016/j.enzmictec.2016.06.005
更新日期:2016-10-01 00:00:00
abstract::This study reports a general strategy for the encapsulation of various enzymes in amphiphilic hollow carbonaceous microspheres (CMs). We found that enzymes could be spontaneously encapsulated in the interior cavity of the CMs via hydrophobic interactions. Due to strong hydrophobic interactions and robust confinement, ...
journal_title:Enzyme and microbial technology
pub_type: 杂志文章
doi:10.1016/j.enzmictec.2015.06.015
更新日期:2015-11-01 00:00:00
abstract::The alkane-1-monoxygenase (alkB) complex of Pseudomonas putida GPo1 has been extensively studied in the past and shown to be capable of oxidising aliphatic C(5)-C(12) alkanes to primary alcohols both in the wild-type organism by growth on C(5)-C(12) alkanes as sole carbon source and in vitro. Despite this, successful ...
journal_title:Enzyme and microbial technology
pub_type: 杂志文章
doi:10.1016/j.enzmictec.2011.01.008
更新日期:2011-05-06 00:00:00
abstract::Progesterone 5β-reductases (P5βRs) are involved in 5β-cardenolide formation by stereo-specific reduction of the △4,5 double bond of steroid precursors. In this study a steroid 5β-reductase was identified in Capsella rubella (CrSt5βR1) and its function in steroid 5β-reduction was validated experimentally. CrSt5βR1 is c...
journal_title:Enzyme and microbial technology
pub_type: 杂志文章
doi:10.1016/j.enzmictec.2019.109483
更新日期:2020-03-01 00:00:00
abstract::Chemical modification of lysine residues in two bacterial alpha-amylases, a mesophilic enzyme from Bacillus amyloliquefaciens (BAA) and a thermophilic enzyme from Bacillus licheniformis (BLA) was carried out using citraconic anhydride. 13 +/- 1 residues in BAA and 10 +/- 1 residues in BLA were found modified under def...
journal_title:Enzyme and microbial technology
pub_type: 杂志文章
doi:10.1016/s0141-0229(01)00296-4
更新日期:2001-04-05 00:00:00
abstract::Nitrification kinetics of synthetic saline wastewater was investigated by using an activated sludge unit. Initial experiments were performed with salt-free wastewater to obtain baseline information. Experiments with 3% salt concentration were performed at different sludge ages in order to investigate the system perfor...
journal_title:Enzyme and microbial technology
pub_type: 杂志文章
doi:10.1016/s0141-0229(01)00312-x
更新日期:2001-05-07 00:00:00
abstract::Mycobacterium tuberculosis acetohydroxyacid synthase (M. tuberculosis AHAS) has been proposed to bean essential target for novel herbicide- and chemical-based antibacterial agents. Therefore, here we investigated the roles of multiple conserved herbicide-binding site residues (R318, A146, Q148, M512, and V513) in M. t...
journal_title:Enzyme and microbial technology
pub_type: 杂志文章
doi:10.1016/j.enzmictec.2015.06.009
更新日期:2015-10-01 00:00:00
abstract::Crocin, one of the major carotenoid pigments of Crocus sativus (saffron), is responsible for antioxidant activity, neuroprotection, and the inhibition of tumor cell proliferation. In order to improve the functionality of crocin, α-glucosyl-(1→6)-trans-crocins (C-Gs) were synthesized using sucrose and dextransucrase fr...
journal_title:Enzyme and microbial technology
pub_type: 杂志文章
doi:10.1016/j.enzmictec.2020.109630
更新日期:2020-10-01 00:00:00
abstract::The present study investigated the influence of low-shear modeled microgravity (LSMMG) conditions on Listeria monocytogenes stress response (heat, cold, and acid), membrane fatty acid composition, and virulence potential as well as stress-/virulence-associated gene expression. The results showed that LSMMG-cultivated ...
journal_title:Enzyme and microbial technology
pub_type: 杂志文章
doi:10.1016/j.enzmictec.2019.109440
更新日期:2020-02-01 00:00:00
abstract::In this work, porous biochar derived from sugarcane bagasse was prepared and then coated with different amounts of chitosan (C@CS) for cellulase immobilization. Cellulase was covalently immobilized on the support by using glutaraldehyde as a linker. The chemical characteristics and morphology of the samples were deter...
journal_title:Enzyme and microbial technology
pub_type: 杂志文章
doi:10.1016/j.enzmictec.2020.109561
更新日期:2020-08-01 00:00:00
abstract::An improved amperometric l-lactate biosensor was constructed based on covalent immobilization of lactate oxidase (LOx) from Pediococcus species onto carboxylated multiwalled carbon nanotubes (cMWCNT)/copper nanoparticles (CuNPs)/polyaniline (PANI) hybrid film electrodeposited on the surface of a pencil graphite electr...
journal_title:Enzyme and microbial technology
pub_type: 杂志文章
doi:10.1016/j.enzmictec.2016.10.014
更新日期:2017-01-01 00:00:00
abstract::Microorganism selection is critical to deglycosylation in soybean fermentation for producing beneficial phytochemicals. This study investigated isoflavone bioconversion in soybean extract inoculated with Lactobacillus plantarum K2-12 and Lactobacillus curvatus JD0-31 exhibiting different enzyme activities. L. plantaru...
journal_title:Enzyme and microbial technology
pub_type: 杂志文章
doi:10.1016/j.enzmictec.2019.109394
更新日期:2020-01-01 00:00:00
abstract::Flocculent yeast Saccharomyces cerevisiae YF234 (MATa ura3-52 trp1Delta2 his ade 2-1 can1-100 sta1 FLO8) cells overexpressing glyoxalase I and having strong flocculation ability were permeabilized with isopropyl alcohol and ethanol under various conditions. The treatment with 40% isopropyl alcohol significantly improv...
journal_title:Enzyme and microbial technology
pub_type: 杂志文章
doi:10.1016/s0141-0229(00)00304-5
更新日期:2000-12-01 00:00:00