Encapsulation and subsequent freeze-drying of Lactobacillus reuteri CRL 1324 for its potential inclusion in vaginal probiotic formulations

Abstract

Probiotic formulations must include a high number of viable and active microorganisms. In this work, the survival of human vaginal Lactobacillus reuteri CRL 1324 during encapsulation, lyophilization and storage, and the activity of encapsulated and/or freeze-dried bacterial cells were evaluated. Extrusion-ionic gelation technique was applied to encapsulate L. reuteri CRL 1324, using xanthan and gellan. Encapsulated and free bacterial cells were freeze-dried with or without lactose and skim milk as lyoprotectors. The different systems obtained were stored at room temperature and at 4°C for 150days. The following determinations were performed: L. reuteri CRL 1324 viability, microorganism released from capsules, survival in a medium simulating the vaginal fluid and maintenance of beneficial properties (growth inhibition of opportunistic pathogenic Streptococcus agalactiae NH 17 and biofilm formation). L. reuteri CRL 1324 encapsulation was efficient, allowing the recovery of a high number of entrapped lactobacilli. The survival of encapsulated L. reuteri during lyophilization and storage was significantly higher in the presence of lyoprotectors. At the end of storage, the highest numbers of viable cells were obtained in free or encapsulated cells freeze-dried with lyoprotectors, stored at 4°C. Encapsulated and/or lyophilized L. reuteri cells maintained their viability in simulated vaginal fluid as well as the ability to inhibit S. agalactiae NH 17 growth and to form biofilm. Encapsulated and freeze-dried L. reuteri CRL 1324 can be included in a suitable pharmaceutical form for vaginal application to prevent or treat urogenital infections in women.

Beneficial rhizobacteria immobilized in nanofibers for potential application as soybean seed bioinoculants

“…caribensis ISIB40 in spinning solutions and nanofibers was determined as log 10 colony forming units (CFU)·g -1 . Survival rate during immobilization was expressed as NAI·NBI -1 , where NAI and NBI are log 10 CFU·g -1 after and before immobilization, respectively [29]. …”

Probiotic lactobacilli in formulas and hygiene products for the health of the urogenital tract

“…The viable bacteria are incorporated frequently as powder, being lyophilization the gold standard technique for microbial preservation and stability during the storage for different time periods. [119][120][121][122] The selection of the appropriate dosage form depends on the physicochemical features of the delivered drug or formula, the target for them and women´s acceptance. 123…”

Technological characterization of vaginal probiotic lactobacilli: resistance to osmotic stress and strains compatibility

“…Also, the technological properties as resistance to lyophilization and storage of concentrated cultures with pharmaceutical excipients in gelatin capsules were studied (Zarate and Nader‐Macías ; Juárez Tomás et al . ), either of lactobacilli individually assayed or combined with a bacteriocin, as salivaricin (Vera Pingitore et al . ).…”

“…Candida albicans, Streptococcus agalactiae, Escherichia coli, Staphylococcus aureus), modulation of the immune system and protection against pathogens in experimental murine model (De Gregorio et al 2014; Nader-Mac ıas and Ju arez-Tom as 2015; De Gregorio et al 2016;De Gregorio et al 2019). Also, the technological properties as resistance to lyophilization and storage of concentrated cultures with pharmaceutical excipients in gelatin capsules were studied (Zarate and Nader-Mac ıas 2006;Ju arez Tom as et al 2015), either of lactobacilli individually assayed or combined with a bacteriocin, as salivaricin (Vera Pingitore et al 2015).…”