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Partial purification and characterization of acylester hydrolase from Lupinus mutabilis

An alkaline acylester hydrolase was partially purified from germinated seeds of Lupinus mutabilis. Hydrolytic activity was absent in the crude extract of ungerminated lupine seed, but it increased and peaked at the fourth day in the germinating seedling. The purification scheme involved homogenization, centrifugation, acetone precipitation, anion exchange chromatography, pH precipitation, and hydr

papiNet - A vehicle for supply chain standardization and integratior

The Paper and Plastics Education and Research Insitute at the University of North Florida and NPTA have taken an initiative to adopt and implement the papiNet standards for supply chain standardization and integration. papiNet can be described as a global standard for the paper and forest industries. The companies, which want to adopt papiNet, are required to follow the standards developed by the

Use of celite-immobilised chloroperoxidase in predominantly organic media

It is possible to use the chloroperoxidase from Caldariomyces fumago to catalyse the oxidation of benzyl alcohol to benzaldehyde in predominantly organic media, even at water activities below 1.0, if the oxidant is tert-butyl hydroperoxide. The enzyme activity increased with increasing water activity and no enzyme activity was observed at water activities below 0.6. Hydrophobic solvents such as cy

From function to process : A logistics-based framework for transforming Tetra Pak business support

This article describes a logistics-based framework for organizational change of service organizations. This framework is based on the key concepts of modern logistics: systems thinking for a holistic approach to business; process orientation for structure of the organization; and process management for continuous change and improvement. The development of logistics as a research and practitioner d

Prediction of the remaining activity of horse liver alcohol dehydrogenase after exposure to various organic solvents

Twenty solvents were selected from a principal component (PC) analysis of 103 organic solvents. The solvents were selected so as to obtain a set of test items that spanned a large range of molecular properties of the selected solvents. The activity of free and Celite-immobilized horse liver alcohol dehydrogenase (HLADH) obtained after 20 h exposure to these solvents were used to create a PLS model

Logistics needs qualitative research – especially action research

This paper describes how qualitative research methods, particularly action research case studies, can contribute to further advance and develop logistics research. The paper also describes limitations with the current dominance of quantitative (especially survey) research in logistics. However, the paper is not a pure criticism of the use of quantitative research methods in general or in logistics

Adsorption of lipase on polypropylene powder

Adsorption of different lipases by EP-100 polypropylene powder from pure and pure lipase preparations was studied. Langmuir isotherms described the adsorption equilibria well both for protein and lipase activity adsorption. Adsorption isotherms for five different proteins all gave a similar saturation level of 220 mg protein per g carrier. Twelve commercial lipase preparations were tested for sele

Fatty acid selectivity of a lipase purified from Vernonia galamensis seed

Vernonia galamensis is an annual herb whose seed oil contains high levels of an epoxy fatty acid, vernolic (cis-12,13-epoxy cis-9-octadecenoic) acid. The seed also contains lipase activity in the dormant state. A lipase was purified from the seed and its substrate specificity studied in isooctane. The lipase shows pronounced selectivity for the native triacylglycerol, trivernolin. The rate of hydr

Assessment of the mobile biofilm microbiome in distributed drinking water following installation of hybrid ultrafiltration process, in Varberg, Sweden.

Drinking water is delivered from the treatment plant to the consumer through kilometres of pipes. Lining these pipes are communities of bacteria living as biofilms. Little is known about the microbial ecology of these biofilms, as access to drinking water pipes for sampling is often limited to pipes sporadically removed for repair or replacement. Bacteria are constantly exchanged between the biofi

Interesterification of phosphatidylcholine with lipases in organic media

Lipases were investigated with respect to their ability to catalyse the incorporation of fatty acids into phosphatidylcholine (PC) by interesterification reactions. The enzymes were dried onto solid support materials and the conversions were carried out in water-saturated toluene. Three lipases (two fungal and one plant enzyme) had the desired activity; immobilized lipase from Mucor miehei (Lipozy

Cross-linked crystals of hydroxynitrile lyase as catalyst for the synthesis of optically active cyanohydrins

Purified hydroxynitrile lyase (HNL) from Manihot esculenta was crystallized by the sitting-drop vapour-diffusion method. The bipyramidal crystals formed (10-20 μm) were cross-linked with different amounts of glutaraldehyde and used as biocatalyst for the synthesis of optically active cyanohydrins. The cross-linked crystals were more stable than Celite-immobilized enzymes when incubated in organic

Improved oligosaccharide synthesis by protein engineering of β-glucosidase CelB from hyperthermophilic Pyrococcus furiosus

Enzymatic transglycosylation of lactose into oligosaccharides was studied using wild-type β-glucosidase (CelB) and active site mutants thereof (M424K, F426Y, M424K/F426Y) and wild-type β-mannosidase (BmnA) of the hyperthermophilic Pyrococcus furiosus. The effects of the mutations on kinetics, enzyme activity, and substrate specificity were determined. The oligosaccharide synthesis was carried out

Modeling the performance of immobilized α-chymotrypsin catalyzed peptide synthesis in acetonitrile medium

A model was developed which describes simultaneous reaction and internal diffusion for kinetically controlled, immobilized α-chymotrypsin-catalyzed, oligopeptide synthesis in acetonitrile medium. The model combines the equations that describe the intrinsic kinetics of four different reactions and the physical characteristics of three different support materials, as determined experimentally, to pr

Enhanced transglucosylation/hydrolysis ratio of mutants of Pyrococcus furiosus β-glucosidase : Effects of donor concentration, water content, and temperature on activity and selectivity in hexanol

The transglucosylation reaction catalyzed by wild-type β-glucosidase CelB from hyperthermophilic Pyrococcus furiosus and active site mutants (M424K, F426Y, M424K/F426Y) was studied. The conversion of pentyl-β-glucoside to hexyl-β-glucoside in hexanol was used as a model transglucosylation reaction. Hydrolysis to glucose was a side reaction. The activity (rates of hydrolysis and transglucosylation)

Optimization of galactooligosaccharide production from lactose using β-glycosidases from hyperthermophiles

The maximal production of galactooligosaccharides (GOS) from lactose by (β-glycosidases from the hyperthermophilic archaea, Sulfolobus solfataricus (LacS) (derived from lacS gene) and Pyrococcus furiosus (CelB) (derived from celB gene) was optimized. The performance of these enzymes under extreme reaction conditions, temperatures up to 95°C and lactose concentrations up to 90% (w/v), were studied.

Lipase-catalyzed reactions in organic and supercritical solvents : Application to fat-soluble vitamin determination in milk powder and infant formula

The aim of this study was to thoroughly investigate the possibility of using enzyme catalyzed hydrolysis and alcoholysis of ester bonds in vitamin A and E esters to facilitate their determination in different food formulas. Two vitamin esters, retinyl palmitate and α-tocopheryl acetate were used as model compounds and two food formulas, milk powder and infant formula, were used as model matrices.

Stability and stabilization of hydroxynitrile lyase in organic solvents

The stability of hydroxynitrile lyase from Hevea brasiliensis has been studied in organic solvents. In dry solvents, the enzyme had half-lives in the range 1400-2500 hours. The enzyme half-life was one order of magnitude lower if the medium was water saturated. The substrates, aldehyde and hydrogen cyanide, were found to promote enzyme deactivation. The deactivation increased with substrate concen