Bioprocess-Engineering-2-exam-filnal.pdf

Bioprocess Engineering 2 exam 1. Explain the importance of bio8n in the L-glutamic acid fermenta8on Biotin, or vitamin B7, is a water-soluble cofactor crucial for enzymes in metabolic pathways, including amino acid synthesis. In microbial fermentation, such as L- glutamic acid...

Bioprocess Engineering 2 exam 1. Explain the importance of bio8n in the L-glutamic acid fermenta8on Biotin, or vitamin B7, is a water-soluble cofactor crucial for enzymes in metabolic pathways, including amino acid synthesis. In microbial fermentation, such as L- glutamic acid production by bacteria like Corynebacterium glutamicum, biotin is essential. It supports the activity of biotin-dependent enzymes, like carboxylases, which play a key role in incorporating carbon dioxide into organic compounds during the biosynthesis of amino acids. While details may vary, biotin likely plays a vital role in supporting enzymes involved in L-glutamic acid production. For precise information, consult recent literature or experts in the field. 2. Explain the importance of the dissolved oxygen tension (DOT) during L-fermenta8on Dissolved oxygen tension (DOT) is crucial in L-glutamic acid fermenta8on. Here's why: Aerobic Preference: L-glutamic acid fermenta8on can occur aerobically or anaerobically. Aerobic condi8ons are preferred, as oxygen is vital for the tricarboxylic acid (TCA) cycle and amino acid biosynthesis. Energy Boost: Aerobic metabolism yields more ATP than anaerobic metabolism. The TCA cycle, essen8al for L-glutamic acid synthesis, operates op8mally with aerobic condi8ons, providing energy for microbial growth. Cellular Respira9on: Oxygen is key for cellular respira8on, releasing energy from organic compounds. Adequate dissolved oxygen supports efficient cellular respira8on, enhancing overall metabolic ac8vity. Redox Balance: Oxygen helps maintain the redox balance within microbial cells. This balance regulates cofactors important for enzymes in L-glutamic acid biosynthesis. Precursor Biosynthesis: Oxygen availability influences the biosynthesis of L-glutamic acid precursors. Oxygen is essen8al for synthesizing key intermediates, impac8ng the overall fermenta8on yield. Cell Growth and Viability: Adequate oxygen levels promote op8mal cell growth and viability. Insufficient oxygen can lead to reduced growth, lower biomass produc8on, and decreased efficiency in L-fermenta8on. Maintaining appropriate dissolved oxygen tension is vital for crea8ng favorable condi8ons, ensuring efficient microbial growth, enhancing L-glutamic acid yield, and contribu8ng to the overall success of the fermenta8on process. 3. What are the major anaplero8c reac8ons during L-lysine fermenta8on? Anaplero8c reac8ons, crucial for L-lysine fermenta8on, replenish key intermediates in central metabolic pathways. In the common pathway involving Corynebacterium glutamicum, major reac8ons include: 1. PEP Carboxylase Reac9on: Converts phosphoenolpyruvate to oxaloacetate, a vital precursor in the TCA cycle for L-lysine synthesis. 2. Pyruvate Carboxylase Reac9on: Transforms pyruvate into oxaloacetate, contribu8ng to TCA cycle replenishment for L-lysine produc8on. 3. Malic Enzyme Reac9on: Catalyzes malate to pyruvate conversion, genera8ng pyruvate for entry into the TCA cycle and L-lysine synthesis. 4. Aspartate Transaminase Reac9on: Converts oxaloacetate and glutamate to alpha-ketoglutarate and aspartate, balancing key intermediates in L-lysine biosynthesis. 5. Anaplero9c Bypass Reac9ons: Specific bypass reac8ons in C. glutamicum strains directly replenish TCA cycle intermediates, aiding in metabolite balance. These anaplero8c reac8ons sustain the TCA cycle, ensuring an ample supply of precursors for efficient L-lysine biosynthesis during microbial fermenta8on. Varia8ons may exist among different microorganism strains used in L-lysine produc8on. 4. What do we call Cleland-Johnson reac8on? 5. What do we call Cleland-Jonhnson reac8on? 6. What are the four biochemical/microbiological stages of biogas forma8on?  1: extracellular stage Large organic compounds are degraded by the extracellular enzymes of certain micro- aerobic and faculta8ve anaerobic bacteria 2: acidogenic stage Polymers are degraded into monomers—organic acid, alcohols, CO2 and hydrogen is formed. Acid tolerant bacteria 3: Acetogenic stage Organic acid and alcohols are converted to mainly ace8c acid 4: Methanogenic stage Ace8c acid, CO2 and hydrogen all converted to methane. Methane forma8on result in ATP genera8on 7. Define water ac8vity! Why is it important for solid state fermenta8on? Water ac8vity is the ra8o between the vapor pressure and vapor pressure of dis8lled water Importance: It influence growth, metabolism, ac8vity of enzymes, metabolic transport process, gas transfer. Higher water ac8vity means more energy and the water can do more work. 8. Characterize the means to control temperature during solid state fermenta8on Temperature control is important aspect of solid fermenta8on (SSF) Temperature can be controlled by various means including: - Incuba8on in a temperature –controlled chamber or room - hea8ng or cooling the substance - insula8on of fermented vessel - use temperature tolerant microorganisms 9. What is the difference in the chemistry structure of diesel and biodiesel ?  -Conven8onal diesel is a low temperature frac8onal dis8llate(175-300celsius) of petroleum fuel oil. It is composed of 15% saturated hydrocarbons and 25% aroma8c hydrocarbons chemical formula is C12H23. -Biodiesel is obtained from vegetables or animal plants which have been trans-esterified with methanol. Biodiesel is ester of triglyceride and a monohydroxy-alcohol 10. Thermotolerant yeasts are frequently employed for bioethanol produc8on, why? They are able to ferment sugars at higher temperatures compared to mesophilic yeasts. This allows for a faster fermenta8on process, which can increase the overall produc8vity and efficiency of bioethanol produc8on. Thermotolerant yeast are less sensi8ve to temp.fluctua8on. They can operate at temp between 35-35 celsius which result in faster sugar conserva8on rates more consistent fermenta8on and reduced contamina8on risk. 11. Characterize biological astaxanthin produc8on (organism, technology, markets, etc ) Red-orange colored Lipid-soluble pigment. This have conjugated double bonds Organism: -Haematococcus pluvialis (fresh water) - Xanthophyllomyces dendroshous (yeast) - Eupausia pacilica (sea plankton) Market: 500M us$/year 6000US$/kg Dietary supplement and feed supplement (colorant for salmon, chicken and egg ) 12. Two organism are used for large scale-ethanol produc8on. Name them and compare the biochemistry of their respec8ve ethanol forma8on? Large scale ethanol produc8on is done by yeast and a bacterium Yeast is a fungus commoly used in fermenta8on of ethanol. It converts sugars such as glucose and carbon dioxide through alcoholic fermenta8on. Bacterium can ferment various sugars, such as glucose, fructose and sucrose into ethanol and CO2 through alcoholic fermenta8on. 13. Characterize the rota8ng drum-type bioreactors ? A rota8ng drum type bioreactors that uses rota8ng drum to cul8vate microorganism or cells. This drum is typically made of a porous material, such as mesh or a perforated surface, which allows for the exchange of nutrients and gases. This type of bioreactor is commonly used in the produc8on of fermented product such as cheese or yogurt and in the cul8va8on of cells for biomedical research 14. Describe the mode of ac8on penicillin and draw its basic structure!