Sodium alginate

The dried rosemary (Rosmarinus officinalis L.) samples cultivated in Turkey were purchased from a commercial organization. The samples were ground and classified according to particle size. Among the particle sizes of 0.5, 1, and 1.5 mm, the highest efficiency was achieved with 1.5 mm. Therefore, particles of this size were used in the extraction study. It was determined that a particle size of 1.5 mm provided the highest efficiency since these results were supported by total phenolic content (TPC) analysis.
All chemical materials (Folin–Ciocalteu reagent, sodium carbonate, 2,2-diphenyl-1-picrylhydrazil (DPPH), ethanol, methanol, 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid (trolox), gallic acid monohydrate, sodium alginate, and calcium chloride dihydrate) were provided by Sigma-Aldrich (St. Louis, MO, USA). The purity of the chemicals is as follows: ethanol (≥99.8%), methanol (≥99.9%), DPPH (≥95%), trolox (≥98%), gallic acid monohydrate (≥99%), sodium carbonate (≥99.5%), sodium alginate (≥98%), and calcium chloride dihydrate (≥96%). Our commercial sodium alginate has a viscosity of 20–400 cP (1% aqueous solutions) [44 (link)]. Zahoor et al. also identified a similar brand of sodium alginate as being of medium viscosity (3500 cP for a 2% w/v solution) [45 (link)]. Its molecular weight is 216.121 g/mol.

Low molecular weight (LMW) CS with a degree of deacetylation of 92.2% (50,000–190,000 Da; viscosity of 1% solution in 1% acetic acid: 42 cP) sodium alginate (Alg), sodium deoxycholate (DS), and sodium tripolyphosphate (TPP) were purchased from Sigma Aldrich (Dorset, UK).

This study used probiotic Lactiplantibacillus plantarum NCIMB 11974 from the National Collection of Industrial Food and Marine Bacteria, an aerobic bacterium with proven anti-inflammatory properties on the intestinal mucosa [31 (link)]. The MRS agar and broth from Carl Roth were used for the growth and development of the probiotic strain. The prebiotics used in all experiments were FOS obtained from BioCare Limited, Birmingham, United Kingdom, and inulin obtained from Dohler, Germany, respectively. For microencapsulation, materials such as sodium alginate and chitosan from Merk, Germany, were chosen due to their gel-forming properties and compatibility with the intestinal environment. The reagents employed for this research were commercially sourced and met analytical grade standards.