Comparative effect of gum arabic and psyllium husk on alginate hydrogels for Lactiplantibacillus plantarum
Natalia Burlaga1, Katarzyna Olechnowicz2, Long D Nghiem3
1Institute of Chemical Technology and Engineering, Poznan University of Technology, Poland; MiCo Scientific Sp. z o. o., Poznan, Poland.
Abstract:
This study examined the effects of gum arabic (GA) and psyllium husk (PH) as functional co-polymers in alginate (ALG) encapsulation matrices for Lactiplantibacillus plantarum, combined with inulin (IN), trehalose (TRE), or their mixture. Probiotic beads were produced by ionic cross-linking and evaluated during short-term refrigerated storage for morphology, metabolic activity, viability, membrane integrity, hydrophobicity, and intracellular trace-metal retention. PH-based hydrogels showed the highest viability, lowest membrane permeability, and improved retention of Mn, Fe, and Zn. These effects are consistent with the hydrated PH-rich network that may facilitate mass transfer and membrane stabilization under refrigerated storage. GA-based systems exhibited greater permeability and hydrophobicity but lower culturability, consistent with denser interfacial layers that may restrict diffusion. Microscopy supported visible morphological differences between hydrogel systems. A conceptual structure-function interpretation is proposed, and ALG-PH-IN and ALG-PH-IN/TRE emerged as the most effective formulations under the tested conditions.
