Microorganisms special

In animals hormones are produced either in special glands (cf. Table 64) or are formed in tissues in which the production of hormones is a biochemical side activity only (so-called tissue hormones). In plants and microorganisms, special hormone-producing glands are absent, but also in plants hormone synthesis is unequal in the different types of cells. Cytokinins, for instance, are produced predominantly in roots and 3-indoleacetic acid in apical meristems. 

Poisonous Animals and Plants. Many people around the world know that certain animals and plants may cause severe poisoning, yet they often take their chances on eating these items if they know of someone else who heis escaped drastic consequences. Therefore, it is noteworthy that, although certain animals and plants are poisonous under all circumstances, others are variable in their toxicities because (1) the animal or plant is poisonous only when it acquires the toxic principle from its food or its environment (2) certain types of processing either develop or eliminate the toxicity in the food (3) the development of poisoning in man depends upon the actions of microorganisms, special enzymes, or other processes which occur in the food or in the human body or (4) only certain stages of maturity in the animal or plant are toxic, me examples of such variable toxicities follow. 

Certain apphcations require that the equipment meet FDA and USDA sanitary requirements. These requirements ensure that the products are not contaminated by extractables or microorganisms from the equipment. Special considerations are given to the design of such equipment (41—44) (see... 

Since the microbiological degradation is a rather specialized reaction, no experimental details are given in this chapter. The success of such a reaction depends not only on the proper choice of substrate and proper duplication of the fermentation medium, but also on obtaining the proper strain of microorganism reported to perform a particular transformation. 

Bioprocess plants are an essential part of food, fine chemical and pharmaceutical industries. Use of microorganisms to transform biological materials for production of fermented foods, cheese and chemicals has its antiquity. Bioprocesses have been developed for an enoimous range of commercial products, as listed in Table 1.1. Most of the products originate from relatively cheap raw materials. Production of industrial alcohols and organic solvents is mostly originated from cheap feed stocks. The more expensive and special bioprocesses are in the production of antibiotics, monoclonal antibodies and vaccines. Industrial enzymes and living cells such as baker s yeast and brewer s yeast are also commercial products obtained from bioprocess plants. 

Batch fermentation means the cultivation of microorganisms, where the sterile growth medium in desired volume is inoculated with the microorganisms into the bioreactor and no additional growth medium is added during the fermentation. The product will be harvested at the end of the process. Typically, PHA s production is performed using batch fermentation because of low cost for investment and no special control. In addition, sterilization of the feed stock is easier than other fermentation processes, and operation is flexible. 

Special reactors are required to conduct biochemical reactions for the transformation and production of chemical and biological substances involving the use of biocatalysts (enzymes, immobilised enzymes, microorganisms, plant and animal cells). These bioreactors have to be designed so that the enzymes or living organisms can be used under defined, optimal conditions. The bioreactors which are mainly used on laboratory scale and industrially are roller bottles, shake flasks, stirred tanks and bubble columns (see Table 1). 

This group of microorganisms shares with chlamydias the property of growing only in living tissue. Rickettsiae occur as small (0.3 x 0.25/mi) rod-shaped or coccoid cells. They can be stained by special procedures. Division is by binary fission. They may be cultivated in the blood of laboratory animals or in the yolk sac of the embryo of the domestic fowl, and it is by this method that the organism is grown to produce vaccines. 

Lactic acid in the vagina gives it an acidic pH (5.0) which together with other products of metabohsm inhibits colonization by most bacteria, except some lactobacilli, which constitute the commensal flora. Other types of baeteria are unable to establish themselves in the vagina unless they have become extremely specialized. These species of microorganism tend to be associated with venereal infeetions. 

Carotenoids with ally lie hydroxy and keto groups such as the 3-hydroxy-4-keto group in astaxanthin which is widespread in marine animals, microorganisms, and algae undergo oxidation in the presence of alkali and air. Eor such samples, saponification is not recommended or must be carried out under anaerobic conditions. Eor this purpose, a special apparatus and procedure were developed by Schiedt et al. ... 

API Serial Dilution Method. The API serial dilution method is the most widely used method for the detection of microorganisms. Field test methods for estimating bacterial populations have been standardized. A standard method dealing with the dose-response (time-kill) testing for evaluating biocides has been established. Sampling methods are of special importance because effective sampling is essential to any successful analysis. 

Biochemical catalysts. Some reactions can catalyzed be by enzymes. The attraction in using enzymes rather than microorganisms is an enormous rate enhancement that can be obtained in the absence of the microorganisms. This is restricted to situations when the enzyme can be isolated and is also stable. In addition, the chemical reaction does not have to cater for the special requirements of living cells. 

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