Formulation of Alginate and Pectin-Based Beads Encapsulating Trichoderma for Sustainable and Efficient Agriculture

The formulation of polysaccharides-based beads encapsulating Trichoderma spp. represents an eco-friendly strategy for promoting sustainable and efficient agriculture [1]. Trichoderma, a beneficial fungus, is well-known for its ability to enhance plant growth, combat phytopathogens, and improve soil health [2]. Encapsulating Trichoderma spores in a polysaccharide matrix provides a protective environment that ensures their viability and facilitates their controlled release into the soil.

Alginate is a natural anionic polymer found in various species of brown algae and certain bacteria. Pectin is an heteropolysaccharide present naturally in the cell walls of all higher plants. Due to their distinctive characteristics [3,4], alginate and pectin are regarded as promising carrier materials for the encapsulation of bioactive agents.

In this work, alginate (Alg) beads, pectin (Pec) beads extracted from orange peel, and Alg/Pec composite beads in a 50/50 (w/w) ratio encapsulating Trichoderma S1 (1.83. 10⁴ conidia/mL ) and S2 (1.56.10⁸ conidia/mL ) were prepared using the ionic gelation method. The Moisture content of the prepared beads was evaluated. The size and shape of the beads were determined by analyzing images obtained by an optical microscope XE3910. The average size of the microcapsules (wet) varied from 1886 ± 6.557 μm to 1942 ± 28.688 μm . All samples were characterized by Fourier transform infrared spectroscopy (FTIR). The overall results demonstrated the successful encapsulation of Trichoderma spp. and highlighted the effects of the different formulations on the physicochemical properties of the beads.