SUSTAINABLE MODIFICATION OF NATURAL STARCHES FOR ADVANCED POLYMERIC APPLICATIONS: GREEN SYNTHESIS STRATEGIES AND CASE INSIGHTS FROM ELEPHANT FOOT YAM STARCH
DOI:
https://doi.org/10.22159/ijap.2026v18i4.58078Keywords:
Starch, Green synthesis, Hydrogel, Sustainable elephant foot yam starch, Biodegradable film, Green solvents, Starch nanocrystal, Green polymeric materialsAbstract
The environmental concerns associated with conventional plastics have driven demand for sustainable polymeric materials. Starch, as a renewable and biodegradable biopolymer, offers an attractive alternative; however, its widespread application is limited by low mechanical strength, moisture sensitivity, and retrogradation. This review summarizes recent advances in green synthesis and modification methods for natural starches to produce advanced polymeric materials. Environmentally friendly approaches are highlighted, including physical (heat–moisture treatment, ultrasonication, irradiation), enzymatic, and green chemical modifications using non-toxic reagents, ionic liquids, deep eutectic solvents, and energy-efficient techniques (microwave assistance). The effects of these modifications on starch structure and functionality are discussed, along with applications in biodegradable films, hydrogels, nanocomposites, and drug delivery systems. Particular attention is given to Elephant Foot Yam (Amorphophallus paeoniifolius) starch—an underexplored but promising raw material with unique physicochemical properties for bioplastics and pharmaceuticals. As a low-glycemic-index, resistant starch source, EFY starch (especially when physically or chemically modified) offers enhanced thermal and rheological properties, as well as sustainability advantages over other starches. Direct comparative cost and performance data against corn and potato starch remain limited, necessitating further application trials. Hydrothermally modified EFY starch produces highly elastic and thermostable gels with superior structural stability under high shear, making it suitable for demanding applications such as processing and thickening. Overall, this review presents sustainable pathways for starch modification to create next-generation green polymeric materials.
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