Julien BENCHEIKH
What is the genesis of this study?
Julien Bencheikh: Before initiating the study, our knowledge regarding yeast-based lyoprotection was not well-developed. Our innovation team developed a prototype and we wanted to validate its performance using a model close to our customers. The objective of this new study was to consolidate this data. Lyoprotectant screening is rarely undertaken by our clients because it requires a lot of time (usually years) and resources. Through this empirical trial, we aimed to demonstrate the efficacy of our product compared to common lyoprotectants. Thanks to this extensive work, we are now able to launch a dedicated offer, specifically for probiotics.
Learn more about how we can support you to enhance long-term viability and vitality of probiotics strains after freeze-drying using an innovative lyoprotectant
Is lyophilization a real challenge in the field?
Julien Bencheikh: Yes, lyophilization is the one of the most used process for the long-term preservation of probiotics and lactic acid bacteria. Achieving the targeted efficiency is a challenge, that it depends on multiple factors and the choice of lyoprotectant is one of them and key.
To date, there is limited empirical data on the effectiveness of different lyoprotectants available in the market. Specifically, during the lyophilization process, probiotic bacteria are exposed to challenging environmental changes, such as temperature, osmolarity, and moisture levels, which often lead to cellular damage. That is why the lyophilization step is so crucial for probiotic producers. Often the lyophilization parameters and lyoprotectants used are highly confidential.
Losses during lyophilization frequently reach 50% and can go up to 80% in some cases. Enhancing survival capacity is therefore a challenge for probiotic bacteria producers and can be achieved in two ways:
- by optimizing the culture medium (a solution we have already proposed)
- by optimizing the lyophilization process itself, particularly the lyoprotectant solution. This study focuses on that objective.
How did you proceed?
Julien Bencheikh: We compared our product, NuCel® Protect 501, to a market standard, maltodextrin. We are aware, of course, that this analysis is not representative of all cases. The results are strain-dependant meaning the product must be tested by our customer with their strains and conditions. Nevertheless, this study serves as a good reference point. We are currently in the process of completing our comparative analysis with other lyoprotectants.
What was the interest of this study?
Julien Bencheikh: We cultured the strain Bifidobacterium animalis subsp. lactis (DSM 10140) in a bioreactor. After biomass concentration, we divided the sample into two fractions. We mixed one with maltodextrin and another with our NuCel® Protect 501. After the freeze-drying step, we incubated the two lyophilizates at different temperatures. The idea was to simulate accelerated aging and product degradation during storage. Traditionally, probiotics are stored at a temperature of 4°C. We then modeled this aging and the behavior of the strain using our internal PREDICT software to observe the results after 6 months, one year, and even up to 24 months.
Did the results meet your expectations?
Julien Bencheikh: Yes, the results were very significant starting from the end of freeze-drying, a phenomenon we did not expect. This difference became even more pronounced over time. The older the product gets, the more the impact of NuCel® Protect 501 has on the viability of Bifidobacterium animalis subsp. lactis (DSM 10140) compared to the maltodextrin lyophilizate. This difference becomes even more significant after 12 months, as the bacteria completely died in the maltodextrin fraction.
The simulation test of gastric juice, performed after freeze-drying, was also convincing for our application. After 90 minutes, both the viability and vitality of the Bifidobacterium animalis subsp. lactis (DSM 10140) strain was preserved. We found that this was not the case with maltodextrin. In other words, NuCel® Protect 501 maintained enough active cells in our simulation test of the gastrointestinal tract.
What can be concluded from this first study?
Julien Bencheikh: This study indicates that our product is particularly effective for the production and viability of the considered strain. It opens new perspectives for applications in probiotic preservation. To date, we are conducting further analyses on other yeast-based fractions to replicate the methodology for other probiotic strains. This is a real challenge as some strains, especially lactobacilli, are particularly sensitive to freeze-drying. This solution must also be compared to other lyoprotectants on the market. Finally, we need to improve our knowledge and understanding of the underlying mechanisms of action.
