Conversion of Sago (Metroxylon sagu) Pith Waste to Fermentable Sugars via a Facile Depolymerization Process

Area of Science:

• Biomass Conversion
• Green Chemistry
• Biotechnology

Background:

• Starchy sago pith waste (SPW) is an abundant lignocellulosic biomass.
• Efficient conversion of SPW into fermentable sugars is crucial for biorefining.
• Current methods often require harsh conditions or are inefficient.

Purpose of the Study:

• To demonstrate the mild-condition conversion of SPW into fermentable sugars.
• To optimize the depolymerization process for high yield and selectivity.
• To identify key parameters influencing SPW conversion.

Main Methods:

• Depolymerization of SPW using oxalic acid catalysis.
• Optimization of reaction parameters including sample loading, catalyst concentration, NaCl concentration, temperature, and time.
• Sequential depolymerization cycles were employed.

Main Results:

• Optimal depolymerization achieved at 2 wt% SPW loading, 100 mM oxalic acid, 25 wt% NaCl at 110°C for 3 hours.
• Up to 97% conversion of SPW into fermentable sugars was obtained.
• High selectivity for glucose production with limited by-product formation was observed.

Conclusions:

• Mild-condition depolymerization of SPW is feasible and efficient.
• Oxalic acid concentration and reaction temperature are critical parameters.
• The process offers a sustainable route for producing fermentable sugars from biomass waste.