Rhamnolipids in lignocellulosic biorefineries: dual roles in waste valorization and process intensification

Area of Science:

• Biotechnology and Bioengineering
• Sustainable Chemistry

Background:

• Lignocellulosic biomass (LCB) is an abundant, low-cost feedstock for biorefineries.
• LCB conversion faces challenges due to structural recalcitrance and high processing costs.

Purpose of the Study:

• To review rhamnolipids as both products and process enhancers for LCB valorization.
• To highlight strategies for improving rhamnolipid production and LCB deconstruction.

Main Methods:

• Literature review of microbial rhamnolipid production from LCB streams.
• Analysis of metabolic engineering strategies for enhanced LCB utilization.
• Examination of rhamnolipids' dual role in pretreatment, saccharification, and fermentation.

Main Results:

• Rhamnolipids can be produced natively from LCB-derived streams, but face titer, rate, and yield limitations.
• Metabolic engineering can improve carbon utilization from LCB.
• Rhamnolipids protect enzymes, mitigate inhibitors, and increase sugar and ethanol yields.

Conclusions:

• Rhamnolipids are a promising biosurfactant for biorefineries.
• Optimizing feedstock, fermentation, and techno-economic factors is crucial for cost-effectiveness and productivity.
• Rhamnolipids can be a game-changer for upcoming biorefineries.