Biosurfactant from Lactiplantibacillus plantarum Tw226 produced using yacon juice and its functionality as emulsifier of essential oils in water emulsions

Abstract

The search for alternative culture media from agro-industrial sources to produce biosurfactants (BS) from lactic acid bacteria is of interest because it reduces production costs and allows circular production systems. This study aimed to evaluate the ability of Lactiplantibacillus plantarum Tw226 to produce BS in a nutrient medium based on yacon juice (BSY), a neglected and underutilized Andean tube, and to compare its functionality as an emulsifier for cinnamon bark and lemongrass essential oil-in-water emulsions. L. plantarum Tw226 reach a dry biomass yield of 1.10 ± 0.06 g L⁻¹ using yacon juice supplemented with 25% MRS broth (MRSJ) and was similar to the one obtain with MRS. The BSY yield was 0.11 ± 0.03 g L⁻¹ and has a surface tension of 43.48 ± 0.68 mN m⁻¹. The FTIR spectra shown that the functional groups of BSY, were similar to those presents in the BS produced in MRS broth (BSMRS). The emulsions of lemongrass and cinnamon bark oil, formulated BSY, had an initial droplet size of 425.9 ± 35.7 nm and 348.2 ± 19.9 nm, respectively. These sizes remained unchanged for 4 weeks, being smaller or similar to those stabilized with the BSMRS. The emulsion of cinnamon bark oil stabilized with BSY did not show creaming compared to the analogous stabilized with the BSMRS. Lemongrass emulsions presented creaming regardless of the BS used. In conclusion, L. plantarum Tw226 could produce a BS using yacon juice with 25% MRS broth which is useful as emulsifier.