Industrially Useful Microbial Processes Questions

• Antibiotic bioassay — cylinder plate method for penicillin: Early official assays measured penicillin potency by the quantity needed to prevent Staphylococcus aureus growth, producing what standard inhibition-zone diameter on a cylinder-plate assay?
• Industrial riboflavin (vitamin B2) biosynthesis: Which microorganism is noted for greater stability and robustness of riboflavin-producing capacity in industrial fermentations?
• Enzyme nomenclature — lactic acid stereochemistry: Which enzyme converts optically active L- or D-lactic acid into an optically inactive racemic mixture (DL-lactic acid)?
• Lactic acid fermentation — in situ neutralization: During lactic fermentations, which compound is commonly added to neutralize produced lactic acid and prevent growth inhibition of lactic acid bacteria?
• Vitamin B12 fermentation — productive species: Among vitamin B12–producing “Pseudomonads” historically cited, which species is recognized as the most productive for industrial cobalamin biosynthesis?
• Auxotroph/analog selection in amino acid processes: Which microorganism listed is commonly selected for resistance to the analog methyl tryptophan when developing overproducing strains for tryptophan pathways?
• History of amino acid biotechnology: Which amino acid was the first to be commercialized at large scale via microbial processes, catalyzing the growth of the amino acid industry?
• Industrial microbiology — selecting a bulk medium for submerged bacterial fermentation In large-scale submerged bacterial fermentation (commercial production), which of the following is most commonly employed as the principal medium/carbon source due to cost and nutrient profile?
• History of vitamins in fermentation — source organism for the first crystalline vitamin B12 isolation Rickes and colleagues recovered active crystalline vitamin B12 from the culture of which microorganism during early industrial vitamin research?
• Food and beverage enzymes — source of protease used for sake flavour development and haze removal Which microorganism is the standard industrial source of the protease employed to enhance flavour and reduce haze in sake processing?
• Downstream processing — timing of vitamin recovery in fermentation In an industrial vitamin fermentation, the product recovery step from the broth is typically scheduled prior to which of the following process steps to protect yield and quality?
• Juice debittering technology — industrial source of naringinase for citrus processing Which microorganism is the standard commercial source of naringinase used to remove the bitter compound naringin from citrus juices?
• Biohydrometallurgy — key microbe in copper bioleaching Which microorganism is the principal industrial agent used in commercial bioleaching operations for copper recovery from low-grade ores and concentrates?
• Actinomycetes in biotechnology — hallmark capability of Streptomyces species Species within the genus Streptomyces are best known in industry and medicine for which of the following activities?
• Fruit processing enzymes — primary industrial source of pectinase for juice yield and clarification Pectinase used to increase juice yield and improve clarity in fruit processing is predominantly produced by which microorganism?
• Stereospecific lactic acid production — organism yielding only L(+)-lactic acid without racemization Which microorganism is known to produce exclusively L(+)-lactic acid (optically pure) with minimal racemization during fermentation?
• Whey valorization — lactose utilization during lactic acid production During lactic acid fermentation of whey-based media (lactose-rich), which microorganism among the following is well-adapted to utilize lactose as the primary carbon source?
• Industrial microbiology — Fungal amylases: In solid (stationary) culture using wheat bran as the substrate, which microorganism is most commonly employed for high-yield amylase production?
• Antibiotic producer identification: Chlorotetracycline (a broad-spectrum tetracycline) is industrially produced by which Streptomyces species?
• Bioprocess classification: The microbial conversion of ethanol to acetic acid (vinegar) is fundamentally which type of process?