Novel Polysaccharide Hydrogels Enriched with Humic Acid for Sustainable Agricultural Applications

Area of Science:

• Agricultural Science
• Materials Science
• Biotechnology

Background:

• Hydrogels are crucial for agriculture, enhancing water retention and nutrient delivery.
• Developing sustainable and biodegradable hydrogels is essential for modern agricultural practices.
• Humic acid (HA) and biopolymers offer potential for improved soil conditioning and plant growth promotion.

Purpose of the Study:

• To develop and characterize humic acid (HA)-enriched hydrogels based on gellan gum (GG) and karaya gum (KG).
• To evaluate the water retention capabilities of these novel hydrogels compared to commercial alternatives.
• To assess the impact of these hydrogels on plant growth and soil health in agricultural applications.

Main Methods:

• Formulation of spermidine (SPD)-ionotropically cross-linked gellan gum (GG) hydrogels with and without karaya gum (KG) and humic acid (HA).
• Structural characterization using FTIR, TGA, mechanical testing, SEM, and swelling kinetics.
• Water retention tests, biodegradation studies, and phytotoxicity assays on Triticum aestivum.

Main Results:

• GG/HA and GG/KG/HA hydrogels demonstrated superior soil moisture retention compared to commercial polyacrylate hydrogels.
• Biodegradation studies confirmed significant weight loss (over one-third) within 30 days.
• No phytotoxicity was observed; GG/KG/HA hydrogels significantly promoted plant growth.

Conclusions:

• GG/KG-based hydrogels enriched with HA are effective sustainable materials for enhancing soil quality.
• These hydrogels show significant potential for improving crop productivity in agricultural systems.
• The developed hydrogels offer a promising eco-friendly alternative for water management in agriculture.