Salt‐Free Aqueous Extraction of a Cell‐Bound Biosurfactant: a Kinetic Study

Abstract

A cell-bound biosurfactant produced by Lactobacillus pentosus was obtained under eco-friendly conditions and used directly as an emulsifying agent in order to stabilize fluorene/water emulsions. The biosurfactant was extracted from L. pentosus cells with an aqueous phosphate buffer solution in the absence of NaCl. This is important because most the cell-bound biosurfactants are extracted in the presence of NaCl, which is considered highly phytotoxic. A pseudo-second order kinetic model best described the batch extraction of the biosurfactant from cells. As expected, the initial extraction rate of the biosurfactant increased with the temperature. Calculation of the activation energy with the Arrhenius equation yielded a positive value, indicating that the process is endothermic. The aqueous solution containing the biosurfactant was able to stabilize fluorene/water emulsions, with relative emulsion values of 62.2 % after 7 days of emulsion formation.

Bioactivity of glycolipopeptide cell-bound biosurfactants against skin pathogens

“…The extraction with PBS was carried at room temperature (25°C) during 2 h at 150 rpm [16]; whereas the extraction with PB was established at 65°C during 1.5 h at 150 rpm according to a previous study [17]. The solutions containing the cell-bound biosurfactants were dialyzed against demineralized water at 4ºC in a Cellu-Sep© membrane (molecular weight cut-off 6000-8000 Dalton; Membrane Filtration Products, Inc., USA) for 48 h, and then the biosurfactants were lyophilized using a lyophilizer CHRIST® Alpha 1-4 LD plus (Germany).…”

Vineyard pruning waste as an alternative carbon source to produce novel biosurfactants by Lactobacillus paracasei

“…The ratio of culture medium:buffer solution used for the extraction was 6:1. The extraction with PBS was performed at room temperature (25 C) and 150 rpm for 2 h [7], whereas the extraction with PB was performed at 65 C and 150 rpm for 1.5 h [31]. Afterwards, the cells were removed by centrifugation (9000 rpm, 20 min) and the remaining supernatant was filtered through a 0.2 mm pore-size filter (Whatman, GE Healthcare, UK).…”

Biological Surfactants vs. Polysorbates: Comparison of Their Emulsifier and Surfactant Properties

“…These biosurfactants can be extracellular or cell-bound [15 -18]. For instance, Lactobacillus pentosus produces a cell-bound glycoli-popeptide biosurfactant that is able to reduce the surface tension of water in 23 units [17,19]. In previous works the biosurfactant produced by L. pentosus showed better emulsifier capacity than polysorbate 20, when it was used as stabilizer agent of oil in water (O/W) emulsions containing rosemary oil [20].…”