This approach utilizes biotechnology to convert renewable resources (e.g., plant fibers) into fibers, primarily through fermentation and enzymatic hydrolysis:

Fermentation: Microorganisms ferment plant-based raw materials (such as corn straw) to produce bio-based monomers (e.g., PLA), which are then polymerized into fibers.

Enzymatic Hydrolysis: Specific enzymes selectively break down fibers (e.g., cotton fibers) under mild conditions, hydrolyzing them into sugars or monomers while minimizing chemical reagent use. However, this technology remains largely in the research and development stage.