Industrial Microbiology and Biotechnology

Isolation and Identification of Microbial Strains for Industrial Applications

  Isolation and utilization of strains that are highly active producers of enzymes (e.g., lipase, xylanase, and alginate lyase), biofuels (e.g., ethanol), bioplastic materials (e.g., lactic acid), or exopolysaccharides (e.g., bacterial cellulose) is crucial for economical industrial bioprocesses. We have isolated novel or high-potential strains for the industrial production of valuable bioproducts, and their products have been fully characterized by various analytical methods such as LC-MS, GC-MS, SDS-PAGE, and FTIR for real applications.

Strain Improvement and Optimization of Fermentation to Enhance Productivity of Target Products

  Cordyceps militaris has been used as a traditional medicinal and edible fungus, and cordycepin (fermentation product of C. militaris) represents immunomodulatory, antioxidant, anticancer, anti-inflammatory, and antimicrobial activities. Its market value was recorded to be USD 473 million. Our research group induced the adaptation of C. militaris to submerged fermentation for industrial processes. The adapted strain was mutated with UV, and the various fermentation conditions were optimized to improve cordycepin production. In addition, other potential industrial strains (Bacillus, Lactobacillus, Ralstonia, Gluconacetobacter, etc) are under development.

  Cordyceps militaris has been used as a traditional medicinal and edible fungus, and cordycepin (fermentation product of C. militaris) represents immunomodulatory, antioxidant, anticancer, anti-inflammatory, and antimicrobial activities. Its market value was recorded to be USD 473 million. Our research group induced the adaptation of C. militaris to submerged fermentation for industrial processes. The adapted strain was mutated with UV, and the various fermentation conditions were optimized to improve cordycepin production. In addition, other potential industrial strains (Bacillus, Lactobacillus, Ralstonia, Gluconacetobacter, etc) are under development.

  Compared with plant cellulose, bacterial cellulose (BC) has high purity, water absorption and retention capacities, crystallinity, and biocompatibility, making it extremely useful in biomedical, food, and cosmetic fields. However, industrial-scale BC production remains challenging due to the unsatisfactory fermentation performance of strains, including low productivity. We designed a UV-C mutagenesis system with limited viability conditions for Gluconacetobacter xylinus, a major BC producer. As a result, G. xylinus LYP25 strain (with 41% improved BC production) was developed, and follow-up research is in progress by applying the LYP25 strain in the fermentation process: Preparation and application of biomass hydrolysate medium; Functionalization of BC from LYP25 for functional foods or materials.