Influence of fermentation time, cryoprotectant and neutralization of cell concentrate on freeze-drying survival, storage stability, and acid and bile exposure of Bifidobacterium animalis ssp. lactis cells produced without milk-based ingredients

Abstract

Aims: To investigate the stability of Bifidobacterium animalis ssp. lactis VTT E-012010 (¼Bb-12) during freezedrying, storage and acid and bile exposure. The effect of harvesting time and composition and pH of the cryoprotectant on the survival was evaluated. The procedure was performed by using a milk-free culture medium and cryoprotectants to produce cells for nonmilk-based applications. Methods and Results: Bifidobacterial cells were grown in fermenters in general edible medium for 15 or 22 h. The cell mass was freeze-dried either as non-neutralized or neutralized using sucrose, betaine or reconstituted skim milk (control) as cryoprotectants. For stability studies freeze-dried powders were stored at 37, 5 and )20°C for 2-6 months. In addition, acid and bile tolerance of the powders was tested. Sucrose-formulated B. animalis ssp. lactis preparations had an excellent stability during storage at refrigerated and frozen temperatures for 5-6 months. They also had a good survival during storage at 37°C for 2 months as well as during exposure to pH 3 and 1% bile acids. No difference was observed between 15 and 22 h grown cells or between non-neutralized and neutralized cells. Betaine proved to be a poor cryoprotectant compared with sucrose. Conclusions: Fermentation time and neutralization of cell concentrate before freeze-drying had no impact on the storage stability and bile and acid tolerance of freeze-dried bifidobacterial cells. The nonmilk-based production protocol using sucrose as a cryoprotectant yielded powdery preparations with excellent stability in adverse conditions (storage at elevated temperatures and during acid and bile exposure). Significance and Impact of the Study: The results indicate that it is feasible to develop nonmilk-based production technologies for probiotic cultures. This provides new possibilities for the development of nondairybased probiotic products.

Improving gastric transit, gastrointestinal persistence and therapeutic efficacy of the probiotic strain Bifidobacterium breve UCC2003

“…Furthermore, UCC2003 derivatives declined at a significantly faster rate in the complex broth compared to the simulated gastric juice. Previously, Saarela et al (2005) observed that pepsin protects bifidobacteria at pH 2.5, suggesting that the reduced toxicity associated with the simulated gastric juice, as opposed to RCM, might be attributed to the presence of pepsin. In any case, improved survival of the complemented strain in gastric juice containing added betaine suggests that it is the compatible solute (accumulated via BetL) that is responsible for the observed increased tolerance to the gastric juice.…”

Effect of water activity and protective solutes on growth and subsequent survival to air-drying of Lactobacillus and Bifidobacterium cultures

“…In addition, although intracellular accumulation of betaine or carnitine can be linked to increased survival to air-drying of lactobacilli (Kets et al 1996), this is not always the case (Linders et al 1997b). Furthermore, betaine can even be detrimental in some processes, for example, survival to a heat treatment (Gouesbet et al 2001) or to freeze-drying (Saarela et al 2005). Therefore, sucrose appears to have been a good choice as a DM ingredient in this study, and the BGP supplements did not improve its efficiency.…”

Guide to designing, conducting, publishing, and communicating results of clinical studies involving probiotic applications in human participants

“…The amount of active probiotic organisms recovered when isolated from different sites or products will depend on methods used for enumeration. [40][41][42] Probiotic administration, delivery and host localization. Probiotic administration is typically via the oral, [43][44][45] rectal, 46,47 or vaginal 48,49 routes.…”