Eco-Friendly Polysaccharides as Moisture Retainers: Influence on Humic Acid Colloidal Stability in Model and Natural...

Area of Science:

• Agricultural Science
• Colloid and Surface Chemistry

Background:

• Hyaluronic acid (HA) and carboxymethyl cellulose (CMC) are eco-friendly polysaccharides with moisture-retention properties, suitable for agricultural fertilizers.
• Humic acids (HAs) possess surface-active properties, indicating potential as replacements for synthetic surfactants in agriculture.

Purpose of the Study:

• To investigate the mutual interactions between humic acids and polysaccharides (hyaluronic acid and carboxymethyl cellulose) at interfaces.
• To evaluate the effect of these interactions on agricultural applications, specifically leaf wetting and nutrient uptake.

Main Methods:

• Radiotracer analysis was employed to study interactions at immiscible liquid interfaces and on plant leaf surfaces.
• Tensiometry, including pendant drop and sessile drop methods, was used to quantify surface activity and wetting behavior.

Main Results:

• Humic acids showed optimal adsorption at 30 g/L hyaluronic acid concentration, irrespective of HA molecular weight.
• Carboxymethyl cellulose decreased the surface activity of humic acids.
• A combination of humic acids and hyaluronic acid improved wheat leaf wetting efficiency compared to individual solutions.
• Humic acids minimally affected the absorption or systemic distribution of hyaluronic acid in plants.

Conclusions:

• The interaction between humic acids and hyaluronic acid offers benefits for agricultural formulations, particularly in enhancing leaf surface wetting.
• Understanding these interactions is crucial for developing effective and eco-friendly agricultural inputs, potentially reducing reliance on synthetic surfactants.