Track topics on Twitter Track topics that are important to you
Enzymatic catalysis to produce molecules such as perfumes, flavors, and fragrances has the advantage of allowing the products to be labeled "natural" for marketing in the U.S., in addition to the exquisite selectivity and stereoselectivity of enzymes that can be an advantage over chemical catalysis. Enzymatic catalysis in organic solvents is attractive if solubility issues of reactants or products, or thermodynamic issues (water as a product in esterification) complicate or prevent aqueous enzymatic catalysis. Immobilization of the enzyme on a solid support can address the generally poor solubility of enzymes in most solvents. We have recently reported on a novel immobilization method for Candida antarctica Lipase B on fumed silica to improve the enzymatic activity in hexane. This research is extended here to study the enantioselective transesterification of (RS)-1-phenylethanol with vinyl acetate. The maximum catalytic activity for this preparation exceeded the activity (on an equal enzyme amount basis) of the commercial Novozyme 435(R) significantly. The steady-state conversion for (R)-1-phenylethanol was about 75% as confirmed via forward and reverse reaction. The catalytic activity steeply increases with increasing nominal surface coverage of the support until a maximum is reached at a nominal surface coverage of 230%. We hypothesize that the physical state of the enzyme molecules at a low surface coverage is dominated in this case by detrimental strong enzyme-substrate interactions. Enzyme-enzyme interactions may stabilize the active form of the enzyme as surface coverage increases while diffusion limitations reduce the apparent catalytic performance again at multi-layer coverage. The temperature-, solvent-, and long-term stability for CALB/fumed silica preparations showed that these preparations can tolerate temperatures up to 70 degrees C, continuous exposure to solvents, and long term storage.
Department of Chemical Engineering, Kansas State University, 1005 Durland Hall, Manhattan, KS, 66506, USA.
This article was published in the following journal.
Name: Journal of biotechnology
Poly(vinyl acetate-acrylamide) microspheres with an average diameter of 2-4μm were successfully prepared and characterized via SEM and FTIR. Then the microspheres were modified with epoxy groups thro...
The filamentous fungus Mucor circinelloides URM 4182 was tested to determine its ability to produce single-cell oil suitable for obtaining biodiesel. Cell growth and lipid accumulation were investigat...
In previous work, a new lipase and its cognate foldase were identified and isolated from a metagenomic library constructed from soil samples contaminated with fat. This new lipase, called LipG9, is a ...
Enzyme-catalyzed production of biodiesel is the object of extensive research due to the global shortage of fossil fuels and increased environmental concerns. Herein we report the preparation and main ...
Using aldehyde-functionalized Pluronic as the reactive surfactant, enzyme-Pluronic conjugates with sizes ranging from nanometers to micrometers were synthesized in reverse emulsions. Compared with the...
The purpose of this study is to determine whether voriconazole is safe and effective for the treatment of serious Candida infection and Candida infection of the esophagus in children and a...
The purpose of this pharmacokinetic and pharmacodynamic (PD) study is: To study the rate and duration of serum cidal activity of caspofungin and micafungin against Candida isolates from t...
The purpose of this study is to look at how people respond to the treatment of warts through use of the Candida Antigen to get an immune response to rid the body of human papillomavirus (H...
This trial is designed to expand the currently available data on the safety and efficacy of alipogene tiparvovec treatment in lipoprotein lipase deficiency (LPLD) and to further the unders...
Candida is the most common fungal pathogen identified in hospitalized patients. This study will seek to enroll adult patients (18 years of age or older) with invasive Candida infections (...
Microbial, plant, or animal cells which are immobilized by attachment to solid structures, usually a column matrix. A common use of immobilized cells is in biotechnology for the bioconversion of a substrate to a particular product. (From Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)
Enzymes which are immobilized on or in a variety of water-soluble or water-insoluble matrices with little or no loss of their catalytic activity. Since they can be reused continuously, immobilized enzymes have found wide application in the industrial, medical and research fields.
Compounds that increase the enzymatic activity of LIPOPROTEIN LIPASE. Lipoprotein lipase activators have a potential role in the treatment of OBESITY by increasing LIPID METABOLISM. Note that substances that increase the synthesis of lipoprotein lipase are not included here.
An inherited condition due to a deficiency of either LIPOPROTEIN LIPASE or APOLIPOPROTEIN C-II (a lipase-activating protein). The lack of lipase activities results in inability to remove CHYLOMICRONS and TRIGLYCERIDES from the blood which has a creamy top layer after standing.
Infection with a fungus of the genus CANDIDA. It is usually a superficial infection of the moist areas of the body and is generally caused by CANDIDA ALBICANS. (Dorland, 27th ed)
Latest News Clinical Trials Research Drugs Reports Corporate
Enzymes are proteins that catalyze (i.e., increase the rates of) chemical reactions. In enzymatic reactions, the molecules at the beginning of the process, called substrates, are converted into different molecules, called products. Almost all chemical re...