Sterile engineering

The fermentation step to produce penicillin GA is the major cost element in the overall process to produce 6-APA. This is substantially due to the high cost of sterile engineering (Table 4.6 and 4.7). Clarification, extraction and solvent recovery steps are also significant, a reflection of the dilute and impure composition of fermentation broths. The concentration of 6-APA in the final broth has a big effect on total process costs. Thus increasing final 6-APA concentrations from 1.2-6.0% have been calculated to reduce production costs by over 50% (Table 4.8). By contrast the 6-APA production step cost is quite small, and is less that half the cost of the solvent recovery process (Table 4.6). The costs of the immobilized enzyme is not insignificant in a recent calculation it was estimated at 2.5 /kg 6-APA (Rasor and Tischer, 1998). 

Sterilizer engineering drawings Sterilizer operation procedure Sterilizer sanitization procedure Sterilizer maintenance procedures Sterilizer specification utilization list Distribution thermocouple location diagrams Temperature sensing unit location diagram (continuous sterilizers) Sterilizer process log sheets... 

Monitoring by Electromechanical Instrumentation. According to basic engineering principles, no process can be conducted safely and effectively unless instantaneous information is available about its conditions. AH sterilizers are equipped with gauges, sensors (qv), and timers for the measurement of the various critical process parameters. More and more sterilizers are equipped with computerized control to eliminate the possibiUty of human error. However, electromechanical instmmentation is subject to random breakdowns or drifts from caUbrated settings and requires regular preventive maintenance procedures. 

Genetic Control. Some Insect pests have been successfully controlled by releasing sterile Insect males in sufficient quantity so that the pest population cannot reproduce. This has proven particularly effective in the control of the screwworm fly, a major pest of cattle (33). Genetic engineers may be able to provide other genetic techniques that will enhance the control of crop pests (34). 

The rHBsAg is produced in an engineered S. cerevisiae strain and is likely purified subsequent to fermentation by a procedure somewhat similar to that presented in Figure 13.10. The final product is presented as a sterile suspension of the antigen absorbed onto aluminium hydroxide (adjuvant), in either single-use vials or pre-filled syringes. It also contains NaCl and phosphate buffer components as excipients. It is intended for i.m. injection, usually as 10 pg in a volume of 0.5 ml for infants/children or 20 pg (in 1.0 ml) for adults. The normal dosage schedule entails initial administration followed by boosters after 1 and 6 months. 

In following text an attempt is made to give an example of the types of documentation that must be prepared within the validation master plant for the installation qualification (IQ) and the operational qualification (OP). The examples given are restricted to the process and installation engineering aspects, and exclude the many other aspects, e. g. sterility, biological or chemical requirements, corporate policies or the production environment. The information described are organized in six categories ... 

Aseptic BPS machines are subject to steam-in-place sterilization following standard CIP cycles. The SIP cycles are routinely measured by thermocouples located in fixed positions along the product pathway. Validation of SIP cycles should be carried out to demonstrate that consistent sterilization temperatures are achieved throughout the equipment to prove that the system can be effectively sterilized. Validation should also identify suitable positions for routine use, or justify the fixed probe positions already in place. The SIP validation is generally carried out with the help of additional thermocouples and should include the use of biological indicators (appropriate for moist heat sterilization). Test locations should include areas which may be prone to air or condensate entrapment. An accurate engineering line drawing of the system to aid identification of suitable test locations and document test locations selected should be available. 

Coronel, P. and Simunovic, J. and Sandeep, K.P. and Cartwright, G.D. and Kumar, P. (2008). Sterilization solutions for aseptic processing using a continuous flow microwave system. Journal of Eood Engineering, 85, 528-536. 

Sawada, H. and Merson, R.L., Estimation of process conditions for bulk sterilization of particulate foods in water-fluidized beds, in Le Maguer, M. and Jelen, P. (eds.). Food engineering and process applications, volume 1 transport phenomena. International Congress on Engineering and Food, Edmonton 1985, Elsevier, London, 1986, 569-581. 

You have just been hired as the chemical engineer for a small soup company. They have just found that their cans of Cream of Spinach soup have become contaminated with a bacteria whose Latin name is retchiosis barfitosum, which fortunately is not lethal but causes serious discomfort. The cans had been sterilized by heating for 1 h in an oven at 200°F, but this procedure apparently was not adequate. We need to sterilize the prepared soup cans to kill the bacteria, which will multiply on the shelf Bacteria concentrations are determined by coating a known amount of the material on a Petri dish and culturing it so that each bacterium forms a colony that can be counted on the dish. 

No amount of sterilization wiU prevent or even slow autooxidation, and there are only two defenses removal of O2 and addition of inhibitors. Oxygen barriers in food packaging are a major topic in the engineering of polymer films. The barrier properties of various polymers are very important in food applications, and many of these are multilayer polymers that have a thin layer of an impermeable polymer (such as polyacrylonitrile and ionic polymers) on a cheaper but O2-permeable polymer such as a polyolefin, which gives mechanical strength to the fikn. 

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