Development and Physicochemical Characterisation of Probiotic Emulsions Containing Lactobacillus rhamnosus for...

Area of Science:

• Microbiology
• Formulation Science
• Dermatology

Background:

• Investigating probiotic survival in topical formulations is crucial for efficacy.
• Biphasic emulsions offer potential delivery systems for probiotics like Lactobacillus rhamnosus GG.

Purpose of the Study:

• To assess how emulsion composition affects Lactobacillus rhamnosus GG viability.
• To evaluate the stability of biphasic probiotic emulsions.

Main Methods:

• Preparation of eight biphasic emulsions (with/without preservative).
• Analysis of pH, FTIR spectroscopy, and emulsion type (O/W).
• Quantification of Lactobacillus rhamnosus GG viability using the plate count method (CFUs).

Main Results:

• Optimal pH for Lactobacillus rhamnosus GG survival was 4.65, promoting proliferation.
• FTIR confirmed emulsion stability and bacterial presence, with consistent spectra over time.
• All tested emulsions supported bacterial growth; preservatives did not inhibit viability.

Conclusions:

• Oil-in-water (O/W) emulsions are suitable for probiotic topical applications.
• The formulation's pH and composition are key factors for probiotic viability.
• O/W emulsions are user-friendly and limit active ingredient penetration, enhancing safety.