Sterilization fermentation

The mixture of broth and mycelium thus formed was then transferred under aseptic conditions to a 3-iiter fermentor containing 2 00 ml of a sterile fermentation medium having the following composition 60 g Cerelose (dextrose hydrate), 18 g soybean meal, 5 g distillers solubles, 12 g cornmeal and tap water in a sufficient amount for a 1,000-ml total volume, adjusted to pH 7.0 to 7.2 with potassium hydroxide. 

Laboratory production of crackers with the same flavor quality as commercial crackers has been difficult. Micka (11) found that when crackers are produced in a laboratory and no starter sponge is kept, and equipment is kept sterile, fermentation is generally retarded and the resulting dough has a high pH and the crackers have an undesirable flavor. Dynn (17) attempted to develop a procedure for the production of experimental crackers to test flour quality. He found that the crackers made from the same batch of flour varied widely in flavor quality and concluded that commercial crackers could not be produced in a laboratory. However, Pizzinatto and Hoseney (4,14) have recently developed a procedure for the production of satisfactory experimental saltine crackers under laboratory conditions. 

Enzyme Preparation. A crude enzyme mixture was prepared from the fermentate of Candida rugosa (American Type Culture Collection, ATCC No. 14830. The rugosa was revived and cultivated in YM Agar slants at 24°C for one week. The growth on one YM Agar slant was transferred aseptically to a two-liter flask containing 400 ml sterilized fermentation medium consisting of 2.0% defatted soyflour,... 

The hot water from Tank 5 also supplies Tank 4 and Pump 3 (or 4), This is necessary to start and finish a batch through the sterilizer. For example, to start, the sterilizer is first steam sterilized (no liquid). At the end of this cycle, hot water from Tank 5 is started through the sterilizer to set or balance the instrumentation. When this is achieved, media is fed to Pump 3 (or 4) by remote operating valves. Similarly, after all the media has been pumped, it is necessary to pump water through the sterilizer until the fermenter volume is correct. If another fermenter is to be filled immediately, the sterile water is diverted to the awaiting empty (and sterile) fermenter, and then the new media for the second fermenter is pumped into the sterilizer. The control room for the operation of a continuous sterilizer should be close to Tank 4, Pumps 3 and 4, the main steam valves and the valves of the sterilizer itself This location is essential to sterilize the empty sterilizer and control the pumping of water and/or media. 

Chatzifragkou A, Papanikolaou S, Dietz D, Doulgeraki Al, Nychas GJE, Zeng AP. (2011). Production of 1,3-propanediol by Glostridhon butyricum growing on biodiesel-derived crude glycerol through a non-sterilized fermentation process. Appl Microbiol Biotechnol, 91,101-112. 

Asymmetric Reduction of Ketones. Baker s yeast (Saccharomyces cerevisiae) is by far the most widely used microorganism for the asymmetric reduction of ketones [850-854]. It is ideal for nonmicrobiologists, since it is readily available at a very reasonable price. In addition, its use does not require sterile fermenters and it can therefore be handled using standard laboratory equipment. Thus, it is not surprising that yeast-catalyzed transformations of nonnatural compounds leading to chiral products have been reported from the beginning of the twentieth century [855] and the first comprehensive review which covers almost all the different strategies of yeast-reductions dates back to 1949 [856]. 

In his review of this process, John Hastings points out that all the problems associated with large-scale sterile fermentations had to be solved how to manufacture a vessel of 125 m capacity with suitable seals and gaskets to allow its sterilization with steam at 12UC how to lay out pipework to prevent the dead-legs where contaminating organisms could accumulate how... 

Figure 1.1 Historical overview of fermentation over the last 350years. Two crucial events triggered the economic success of biotechnology. The first was the development of large-scale sterile fermentation technology for the production of penicillin during the Second World War. The second was the development of genetic engineering tools for horizontal gene transfer, which...

Even though these special application examples demonstrate the scalability of the technology, and although airlift reactors have long been used for shear-sensitive cell-culture applications, the CSTR design has become the standard for microbial and mammalian cell suspension culture. Its design is versatile, and cultivations can be scaled from the laboratory to pilot scale and to up to 300 m in fully contained sterile fermenters. 

As discussed before, CSTR is the most used reactor design for submersed cultivation of practically all prokaryotic and eukaryotic cells listed in Table 1.1, as it can be scaled from small laboratory scale through pilot scale to 300 m fully contained sterile fermenters. 

Some commodities, organic acids, ethanol, and yeast biomass are produced under nonsterile conditions because either the scale of operation exceeds 200-300 m or the operating costs for sterile fermentations would be prohibitively high. 

Pigment Vegetable Freezing Blanching Sterilization Fermentation... 

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