A novel polysaccharide from Macadamia peel: Extraction, purification, structural characterization and antioxidant...

Area of Science:

• Food Chemistry
• Biotechnology
• Agricultural Science

Background:

• Macadamia peels are a rich source of bioactive compounds like polysaccharides.
• These compounds possess known anti-tumor and anti-oxidation properties.
• Peels represent a significant agricultural by-product with potential for valorization.

Purpose of the Study:

• To extract and purify polysaccharides from macadamia peels.
• To characterize the structural and functional properties of these polysaccharides.
• To evaluate their antioxidant potential for various applications.

Main Methods:

• Ultrasonic-microwave-aided water extraction and purification using DEAE-52 and Sephadex G-50 columns.
• Characterization via Fourier-transform infrared spectroscopy, SEM, AFM, NMR, and GC-MS.
• Antioxidant activity assessed using DPPH, hydroxyl radical scavenging, and reducing power assays.

Main Results:

• Two purified polysaccharide fractions, MPP-1 and MPP-2, were obtained, primarily composed of glucose.
• Molecular weights were determined as 8.16 kDa (MPP-1) and 7.73 kDa (MPP-2).
• Both fractions exhibited significant antioxidant activity, with MPP-2 showing superior efficacy.

Conclusions:

• Novel glucose-rich polysaccharides (MPP-1, MPP-2) from macadamia peels display potent antioxidant properties.
• This study enhances macadamia waste utilization, reducing environmental impact.
• These findings suggest promising applications for macadamia peel polysaccharides as natural antioxidants in functional foods.