High-pressure homogenizers system

Recovery. The principal purpose of recovery is to remove nonproteinaceous material from the enzyme preparation. Enzyme yields vary, sometimes exceeding 75%. Most industrial enzymes are secreted by a microorganism, and the first recovery step is often the removal of whole cells and other particulate matter (19) by centrifugation (20) or filtration (21). In the case of ceU-bound enzymes, the harvested cells can be used as is or dismpted by physical (eg, bead mills, high pressure homogenizer) and/or chemical (eg, solvent, detergent, lysozyme [9001 -63-2] or other lytic enzyme) techniques (22). Enzymes can be extracted from dismpted microbial cells, and ground animal (trypsin) or plant (papain) material by dilute salt solutions or aqueous two-phase systems (23). 

In the past, the majority of high-pressure homogeneous catalytic reactions were conducted in batch systems, which may cause problems in scale-up for SCFs because of the higher pressures needed for achieving the supercritical state. Therefore, continuous processing has also been investigated in the last years. It would be preferable for industrial-scale SCF reactions, because it involves smaller and, hence, safer equipment [144-150]. In addition, capital costs are likely to be lower than in batch systems. 

Fig. 49 Relationship d32 =/(Ap) for different emulsifiers. ZKDM-teeth ringed rotor-stator emulsifier, CM - colloid mill, HPH - high pressure homogenizer. Details on the material system in text from [74]...

To get a better idea of how to formulate the nanosized emulsion delivery systems suitable for parenteral, ocular, percutaneous, and nasal uses, the reader is referred to more detailed descriptions of methods of nanosized emulsion preparation [6, 116], A hot-stage high-pressure homogenization technique or combined emulsification technique (de novo production) is frequently employed in order to prepare nanosized emulsions with desired stability even after subjection to autoclave sterilization. Therefore, the steps involved in this technique in making blank anionic and cationic emulsions were arranged in the following order ... 

Membrane emulsihcation has been recently proposed for the preparation of stable and uniform-sized microcapsules [27]. Membrane emulsihcation is a technology that allows to obtain uniform emulsions at low energy input compared to the emulsion prepared using high-pressure homogenizers and rotor/stator systems therefore, it is very useful for the preparation of emulsions containing labile compounds such as bioactive molecules sensihve to shear stress [28]. 

Traditional methods of emulsification include high-pressure homogenizers, rotor-stator systems, and ultrasound homogenizers [110, 111], The first two examples employ high mechanical shear rates to produce small droplets of the... 

In the PIT method, an initial emulsion, for example, a W/0 emulsion, is heated up to a temperature, called PIT, for which the interfacial tension between the oil and water phases reaches a minimum. At this point there is an inversion, and an O/W emulsion is formed. The system is then cooled while stirring and a stable microemulsion is formed. Sometimes high-pressure homogenization is used to prepare microemulsions, but this method is limited due to the high heat dissipation involved. 

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