Probiotics have been known to be orally delivered for potential treatment of gastro-intestinal tract infections (GIT). Microencapsulation has successfully been identified as a good method to protect the probiotics from harsh environment of GIT system during oral delivery. Surface modification of probiotics and entrapping it with bio therapeutics compounds for oral delivery has not been explored, therefore, the study evaluated efficiency of surface modified Lactobacillus plantarum (L. plantarum) subsp. plantarum CICC 6240 for oral delivery of bovine serum albumin (BSA). The encapsulating materials were evaluated for swelling behavior in different simulating fluids. Alginate was crosslinked with CaCl₂ and freeze-dried to obtain calcium alginate microcapsules. Additionally, calcium hydrogen phosphate microcapsules were obtained by adding Na₂HPO₄ to calcium alginate microcapsules. The probiotic L. plantarum was surface modified with 1% sodium alginate and crosslinked with calcium chloride to obtain calcium alginate cells. Finally, precipitate layer of Na₂HPO₄ was added to obtain mineralized cells. The surface modified cells L. plantarum was entrapped with BSA.
The microcapsules showed a good swelling behavior hence good material for modifying the cell surface. FTIR confirmed the chemical structure of the entrapped BSA on the cell surface. Entrapment efficiency showed a high percentage (>90%) of the BSA was entrapped on the cell surface. A high percentage (> 40%) of BSA release from cell surface was observed. Colony growth of L. plantarum on the surface of Man-Rogasa-Sharpe (MRS) agar confirmed growth of the surface modified BSA-entrapped cells after exposing to the simulated intestinal fluid (SIF) and simulated gastric fluid (SGF).
The probiotic cell was surface modified successfully with the polyelectrolytes without interference of the cell functionalization. The cell surface modified L. plantarum can find its potential applications in biomedical field as a carrier for delivery of other beneficial human bio therapeutics components.
 

BSA, Bio therapeutics, GIT, Microencapsulation, Probiotics, Swelling behavior