Comparative study of polyphenolic compound extraction from empty palm fruit bunches and sugarcane pulp

Area of Science:

• Agricultural Chemistry
• Natural Product Chemistry
• Food Science

Background:

• Polyphenolic compounds, known for their antioxidant properties, can be sourced from plant materials and agricultural waste.
• Sugarcane pulp and empty palm fruit bunches are abundant agricultural byproducts with potential for valuable compound extraction.

Purpose of the Study:

• To identify optimal solvents and simple extraction methods for maximizing total phenolic and flavonoid yield from sugarcane pulp and empty palm fruit bunches.
• To correlate polyphenol yield with antioxidant activity using established assays.

Main Methods:

• Extraction methods evaluated: maceration, Soxhlet extraction, and ultrasound-assisted extraction (UAE).
• Solvents tested: water, 70% methanol, and 70% ethanol.
• Antioxidant activity assessed using DPPH (2,5-diphenyl-2-(4,6-di-tert-butyl-2,5-hydroxyphenyl)-2H-hydrazyl) and FRAP (Ferric Reducing Antioxidant Power) assays.

Main Results:

• Soxhlet extraction with 70% methanol yielded the highest amounts of total phenolic compounds, flavonoids, and FRAP antioxidant activity from both sugarcane pulp and palm bunch waste.
• This method resulted in approximately double the yield of polyphenols and antioxidant activity compared to other tested solvents and extraction techniques.
• DPPH assay indicated promising antioxidant activity, though trends across solvents and methods were less conclusive.

Conclusions:

• Soxhlet extraction using 70% methanol is a highly effective method for extracting valuable antioxidant polyphenols from agricultural wastes like sugarcane pulp and palm bunch waste.
• This research highlights the potential of utilizing these byproducts as sustainable sources of natural antioxidants.