Eco-friendly microencapsulation of Lacticaseibacillus paracasei using Ficus pumila seed extract: A novel plant-based delivery system enhancing probiotic stability and gastrointestinal tolerance

Probiotic viability remains a critical challenge during gastrointestinal (GI) transit, storage, and feed processing. Conventional encapsulation materials often fail under acidic and thermal stress. This study aimed to develop and characterize a novel, eco-friendly microencapsulation system using Ficus pumila (FP) seed extract as a natural encapsulating matrix for Lacticaseibacillus paracasei (LP) WU2502, enhancing its functional resilience and storage stability.

Microcapsules containing LP and FP were formulated through ionic gelation using calcium chloride. Physicochemical properties were assessed using scanning electron microscopy and Fourier-transform infrared (FTIR). Functional evaluations included encapsulation efficiency (EE), swelling kinetics, controlled release in simulated gastric and intestinal fluids, stress tolerance (acid, bile, enzymes, thermal), and viability during 60-day storage at 4°C and 25°C.

The LP/FP microcapsules demonstrated high EE (80.5%) and spherical morphology (~200μm). FTIR confirmed the presence of ionic and hydrogen bonding in the matrix. The system exhibited pH-responsive swelling and controlled release, reaching 89.17% cumulative release in intestinal fluid. Encapsulated cells showed significantly improved tolerance to acidic pH, bile salts, digestive enzymes, and heat compared to free cells (p < 0.05). After 60 days, the viability of encapsulated cells remained above 60% at both storage temperatures, while free cell viability dropped by over 85%.

FP seed extract offers a biodegradable, plant-derived alternative for probiotic encapsulation. The developed LP/FP system effectively enhances probiotic survival under GI and thermal stress and during extended storage. These results support its application as a sustainable delivery platform for animal feed and functional food formulations.