Film Coating as a New Approach to Prepare Tablets Containing Long-Term Stable Lactobacillus acidophilus

This work presents a study of film coating with the vaginal strain of Lactobacillus acidophilus, the aim of which was to dry the bacteria and manufacture probiotic tablets in one step and to enhance the survival rate of bacteria and their viability during storage. The results show that the film coated lactose-based tablets contained viable bacteria and the survival rate after the process was 21 %, which could be enhanced up to 59 % by applying protective media (trehalose, sucrose, reconstituted skim milk (RSM)) during dehydration. Additionally, protective agents improved the viability of bacteria during storage too. After one year, 20 % of the embedded bacteria were active when stored at -20 degrees C, and viability dropped only one order of magnitude when stored at 7 degrees C. It was verified that the bacteria in film coated tablets were not sensitive to higher levels of humidity owing to the moisture-moderating polyvinyl alcohol-based coating composite. The described technology for production of tablets containing living bacteria by tablet coating seems industrially feasible as tablet film coaters are widespread in the pharmaceutical industry.