Skip to main content

Posts

Showing posts from January, 2015

Anaerobic Wastewater Treatment Troubleshooting : Sulphate reduction bacteria

1) Sulphate reducing bacteria that can only oxidize their substrate into acetate. i.e, desulfobacter strain, desulfovibrio strain, desulfobacterium strain, desulfosarcina strain, desulfotomaculum strain. 2) Sulphate reducing bacteria that can oxidize their substrate completely to carbon dioxide. i.e. , Desulfobulbus strain, desulfomonas strain, desulfovibrio strain. 3) Dissimilatory sulphate & Bisulphate reduction. i.e, Desulfovibrio vulgaris, desulfotomaculum strain, desulfovibrio gigas, desulfovibrio desulfuricans, desulfomicrobium, desulfomonile, desulfuramonas, desulfurella, sulfurospirillum, etc. 4) Chemotrophic aerobic  sulfur oxidation. i.e., thiobacillus thioparus and thiobacillus strain, pseudomonas strain. etc. 5) phototrophic anaerobic oxidation of sulfur compounds : chromatiaceae, rhodospirillaceae,etc.

Immobilization of Yeast Cells

Objective To Immobilize active Yeast Cells in the Calcium Alginate Gel and to check the viability of cell by  invertase activity   Introduction The term ‘immobilization’ was first proposed at the first enzyme engineering conference in 1971.  Immobilization often causes a dramatic change in the apparent measuring parameter of the enzyme  catalyzed by Michalis – Menton constant, temp optima, pH optima, and effect of inhibitors may be  changed when an enzyme in immobilized. The degree and nature of these changes not only depends  on the immobilization but also on the enzyme reaction. There are various methods available for immobilization of enzyme Absorption Covalent binding Cross matching Micro encapsulation Polymerization Gel entrapment Advantages of enzyme- immobilization Stability of the enzyme immobilization increases even in adverse condition. Resistance of enzyme molecules against metal ion

Media Formulation

Thorough analysis is essential to establish a suitable medium for an individual fermentation process All most all microbes need water, energy sources, sources of carbon and nitrogen, certain mineral elements and perhaps vitamins plus oxygen if microbes are aerobic It is easy to devise a medium containing pure compounds on a small scale but this medium may be unsuitable for use in a large scale fermentation processes Following are the criteria imperative to  consider while designing a medium for large scale production ~ The medium should support the maximum production of yield of product per gram of substrate used ~ It should promote maximum accumulation of  the product ~The maximum rate of product formation should be achieved  ~There should be minimum production of unwanted products ~Constituents of the medium should be available throughout the year at cheaper rate and nearby area ~There should not be any undesirable changes in the consistency o

The Development of Inocula for Yeast Processes

Industrial fermentations utilizing yeasts are the brewing of beer, the production of Baker’s Yeast (biomass) and recent processes have also been established for the production of recombinant products. Brewing Inocula for Yeast Process Yeast can be used to inoculate a fresh batch of wort from previous fermentation or from propagator. It is common practice in the British brewing industry to use the yeast from the previous fermentation.   The brewing terms used to describe this process and 'crop', referring to the harvested yeast from the previous fermentation, and 'pitch', meaning to inoculate. One of the major factors contributing to the continuation of this practice is the wort-based excise laws in the United Kingdom where duty is charged on the sugar consumed rather than the alcohol produced. Thus, dedicated yeast propagation systems are expensive to operate because duty is charged on the sugar consumed by the yeast