Chapter 28: Applied and Industrial Microbiology

Together, these fields drive innovations in food production, pharmaceuticals, biofuels, waste treatment, and more. The chapter discusses the use of fermentation technology, which involves cultivating microbes in controlled environments (fermenters) to produce substances such as antibiotics, amino acids, enzymes, organic acids, and vitamins. It introduces aerobic and anaerobic fermentation, and how factors like pH, temperature, oxygen, and nutrient availability are managed to optimize microbial growth and metabolite production. Key industrial products like citric acid from Aspergillus niger, glutamic acid, lactic acid, and acetic acid are explained along with their commercial significance. Enzyme production using microbes is another focus area, with applications ranging from detergents to high-fructose corn syrup. The chapter highlights microbial biosynthesis of amino acids (like lysine and methionine), vitamins (B12, riboflavin), and steroids. It then delves into antibiotic production, especially the historical discovery of penicillin and the role of Streptomyces and fungi in producing secondary metabolites. Recombinant DNA technology is introduced as a transformative force in applied microbiology. The use of genetically modified organisms (GMOs) allows microbes to produce human proteins such as insulin, growth hormone, and vaccines. The chapter also introduces bioconversion (using microbes to convert biomass into useful products) and biofuels, particularly ethanol and methane. Applications in food microbiology include the use of lactic acid bacteria in yogurt and cheese production, yeast in bread and alcohol fermentation, and microbial enzymes for flavor enhancement. Microbial spoilage, food safety, and the role of probiotics and starter cultures are also discussed. The chapter concludes with a review of biosensors, bioreactors, and single-cell protein as future-focused technologies in microbial manufacturing. It emphasizes how industrial microbiology supports sustainability, resource efficiency, and global health through the development of biobased products.