Freeze-dried biotics based on Lactiplantibacillus plantarum and Lactiplantibacillus paraplantarum with enhanced selected biological activity

Abstract

Two lactic acid bacteria strains with probiotic potential (Lactiplantibacillus plantarum MIUG BL21 and Lactiplantibacillus paraplantarum MIUG BL74) were used to produce paraprobiotics and postbiotics, respectively. The paraprobiotics were obtained by inactivation of Lactiplantibacillus plantarum MIUG BL21 strain by using a combined ohmic-thermal treatments. The postbiotics were produced by Lactiplantibacillus paraplantarum MIUG BL74 by fermentation of a bovine colostrum-based medium. Paraprobiotics were added before fermentation, whereas the fermented medium was used to develop four customized freeze-dried biotics formulas. The freeze-dried biotics showed a probiotics survival rate varying between 75% and 84%, whereas different polyphenolic profile was highlighted, with the highest total content of ∼8843 μg/g dry weight (DW) in the variant based on whey protein isolate and β-cyclodextrin. The biotics highlighted a wide range of free and bounded phenolic profile, with theaflavin as the main representative in samples containing whey protein isolate and carboxymethylcellulose (∼3841.11 μg/g dry weight (DW) and in the formulation containing β-cyclodextrin (∼2929 μg/g DW), respectively. Four short-chain fatty acids were identified, with lactic acid as predominant compound. All the samples showed a cytocompatibility, antitumor properties and inhibitory activity against α-amylase and lipoxygenase. The presence of encapsulated probiotics as spheroidal structures were evidenced in all samples.