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Basics of Fermentation

While enzymes can be prepared from cells grown in either batch or continuous culture, we will cover only batch fermentation here as, even for pilot-scale biocatalysis runs, the amounts of enzyme obtainable in a batch fermentation are sufficient. [Pg.212]

There are four characteristic features that differentiate a fermentation from most other reactions (i) the requirement to work under sterile conditions (ii) the auto-catalytic nature of fermentation which necessitates a starting amount of cells, the inoculum (iii) the need to sparge air or oxygen into the fermenter and (iv) the need for other elements such as C, N, P, S, and others discussed below. [Pg.212]


The basic process technology in vaccine production consists of fermentation for the production of antigen, purification of antigen, and formulation of the final vaccine. In bacterial fermentation, technology is weU estabHshed. For viral vaccines, ceU culture is the standard procedure. Different variations of ceU line and process system are in use. For most of the Hve viral vaccine and other subunit vaccines, production is by direct infection of a ceU substrate with the vims. [Pg.361]

Although dynamic responses of microbial systems are poorly understood, models with some basic features and some empirical features have been found to correlate with actual data fairly well. Real fermentations take days to run, but many variables can be tried in a few minutes using computer simulation. Optimization of fermentation with models and reaf-time dynamic control is in its early infancy however, bases for such work are advancing steadily. The foundations for all such studies are accurate material Balances. [Pg.2148]

The tetracyclines are valuable orally active broad-spectrum antibiotics prepared by isolation from the fermentation liquors of various strains of Streptomyces or by chemical transformation of fermentation-derived substances. The basic ring system and numbering pattern is as follows ... [Pg.212]

Water represents one of the most important raw materials used in biopharmaceutical manufacture. It is used as a basic ingredient of fermentation media, and in the manufacture of buffers used throughout product extraction and purification. It represents the solvent in which biopharmaceutical products sold in liquid form are dissolved, and in which freeze-dried biopharmaceuticals will be reconstituted immediately prior to use. It is also used for ancillary processes, such as the cleaning of equipment, piping and product-holding tanks. It is additionally used to clean/rinse the vials into which the final product is filled. [Pg.104]

In this chapter, we study various correlations for gas-liquid mass transfer, interfacial area, bubble size, gas hold-up, agitation power consumption, and volumetric mass-transfer coefficient, which are vital tools for the design and operation of fermenter systems. Criteria for the scale-up and shear sensitive mixing are also presented. First of all, let s review basic mass-transfer concepts important in understanding gas-liquid mass transfer in a fermentation system. [Pg.223]

Newton s explanations were, in contrast, based on the idea that bodies acted and interacted through their forces or active principles. He had stated, in the preface to his greatest work, The Principia Mathematical Principles of Natural Philosophy, that this was the way to proceed For the basic problem of philosophy seems to be to discover the forces of nature from the phenomena of motions and then to demonstrate the other phenomena from these motions.. .. If only we could derive the other phenomena of nature from mechanical principles by the same kind of reasoning The Principia had shown that gravity was one such force. It might well be that the cause of fermentation was another. In chemical reactions, such as fermentation, forces operated at very small distances. An understanding of the operation of these short-range forces would provide an explanation for chemical phenomena. [Pg.28]

Solvent extraction has long been established as a basic unit operation for chemical separations. Chapter 7 summarizes the effects of temperature, pH, ion pairs, and solvent selection on solvent extraction for biomolecules. Solvent extraction of fermentation products such as alcohols, aliphatic carboxylic acids, amino acids, and antibiotics are discussed. Enhanced solvent extraction using reversed micelles and electrical fields are also discussed. Solvent-extraction equipment and operational considerations are adequately covered in this chapter. [Pg.10]

To describe the behavior of a sample of gas, we need four basic descriptors the temperature of the gas, the pressure of the gas, the volume the gas occupies, and the amount of gas, usually given in the number of moles of whatever gases are present. For instance, if I told you I had a mole of a particular gas at 25°C (77°F) and this gas had a volume of 22.4 liters (about six gallons) at ambient pressure, you would have all the information you would need to predict the behavior of that gas should the pressure or temperature change. This information would be essential for our chemical engineer, our deep-sea diver, and even our winemaker. One of the products of fermentation is carbon dioxide, and if this gas is poorly contained or controlled, the corks that pop will be unintentional. [Pg.154]

A rather more futuristic aspect of fermentation control is the use of complex parameters, calculated from basic and biochemical parameters (Fenge et aL, 1991 ... [Pg.288]

Lagers comprise more than 95% of the brew sold in the U.S. A., but just over 40% of the beer sales in Canada, and less than 5% of the beer sold in the U.K. More than 50% of the beer sold in Canada and nearly 90% of that sold in the U.K. is an ale. The basic difference between these brews is that, an ale is produced by a top-fermenting yeast, such as Saccharomyces cerevisiae, from which the yeast is skimmed from the top of the beer on completion of fermentation. Fermentation with these yeasts is carried out at 15-20°C, slightly higher than bottom fermentations. Ales are also hopped at a higher rate than lagers, which gives the product its characteristic more bitter, hoppy flavor. [Pg.517]

With the advance of fermentation technology (antibiotics, citric add, essential amino acids, etc.) interest has increased in the supply of aerial oxygen to more viscous and non-Newtonian liquids. It is thus not surprising that the first important study of mass transfer in C/L systems [64, 65] was linked in its title to industrial fermentation and that the bubble column has been adopted as a classical apparatus for this basic operation in chemical technology having first been used in fermentation technology. [Pg.145]

One of Boerhaave s predecessors at the University of Leyden, a prominent participant in chemical discussions in the later seventeenth century, was Franciscus de le Boe Sylvius (1614-1672). Sylvius had practiced medicine both at Hanau and Amsterdam before joining the medical faculty at Leyden in 1658. From that position he represented both experimental anatomy and medical chemistry, and he made use of chemical explanations to describe both the nature of disease and the functions of the body. Like van Helmont before him, Sylvius gave his attention to fermentation and concluded that the process of fermentation was essential to the physiological process of digestion. Van Helmont had also suggested that the fermentation that accounted for digestion, although due ultimately to a spiritual force, was also affected by the operation of acid in the body and, indirectly, by the presence of alkali. In that muted moment, a new view of the basic components of the chemical operation of the body was born—the acid/alkali theory. What bubbled up from this theoretical mixture continued to interest chemical writers for several decades thereafter. [Pg.116]

The operation of fermenters is basically the same regardless of size, but seed fermenters usually do not have sterile anti-foam and nutrient feeds piped to the tanks as the main fermenters have. Therefore, foaming in the seed fermenters can lead to infection, which is one of the reasons they need more attention. Careful inoculation procedures, sampling and sterilizing the transfer lines from the seed fermenter require alert personnel. Careful attention to these details is more important than the proximity of the seed and main fermenters. [Pg.73]


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