RESUMO
This study evaluated the protective effects of different synbiotic microcapsules on the viability of encapsulated Lactiplantibacillus plantarum GIM1.648 fabricated by electrospraying. The optimum amount of substrate for three synbiotic microcapsules separately containing fructooligosaccharide (FOS), fish oil, and the complex of both were 4% FOS (SPI-F-L-P), 20 µL fish oil (SPI-O-L-P) and the complex of 20 µL fish oil, and 2% FOS (SPI-O-F-L-P), respectively. The obtained synbiotic microcapsules had a better encapsulation efficiency (EE) and survival rate (SR) after in vitro digestion than microcapsules without the addition of substrate (SPI-L-P) and SPI-O-F-L-P presented the highest EE (95.9%) and SR (95.5%). When compared to SPI-L-P, the synbiotic microcapsules possessed a more compact structure as proved by the SEM observation and their cell viability were significantly improved in response to environmental stresses (heat treatment, freeze drying, and storage). The synbiotic microcapsules containing the complex of FOS and fish oil showed the best beneficial effect, followed by ones with fish oil and then FOS, suggesting the FOS and fish oil complex has more potential in application.
RESUMO
To improve the survivability of probiotics under the harsh conditions, a novel double-layered vehicle, which was developed by a one-step coaxial electrospinning procedure, was here used to encapsulate the probiotics. The morphology characterization analysis revealed that the electrospun fiber had a beaded morphology and core-shell structure. Probiotic cells were successfully encapsulated in the fibers (107 CFU/mg) and exhibited an oriented distribution along the fiber. Additionally, the encapsulation of core-shell fiber mat enhanced the tolerance of probiotic cells to simulated gastrointestinal conditions and no significant loss of viability was found (p > 0.05). Besides that, the encapsulated cells exhibited better thermal stability under heat moisture treatment, lower loss of viability (0.32 log CFU/mL) was occurred when compared with the free cells or encapsulated cells in uniaxial fiber mat. In conclusion, this double-layered vehicle presents a great potential in probiotic encapsulation and improving their resistant ability to the harsh conditions.