The cryoprotective effect of egg yolk and polyvinylpyrrolidone on the survival of Lactobacillus plantarum during lyophilization

As the demand for probiotic supplements increases, so does the need for high-quality probiotics and their long-term preservation. Lactobacillus plantarum is one of the most useful probiotic bacteria that are widely used in fermentation products and probiotic supplements. To preserve Lactobacillus plantarum powders in good condition, a variety of maintenance approaches have been developed and used. One of these methods is freeze drying. In the biological sciences, freeze drying is a well-known technique. The cell is damaged throughout the freezing and drying process, which is one of the major drawbacks of this technique. Various cryoprotectants have been developed and utilized to reduce this damage. In the first phase of this study the cryoprotectant efficacy of egg yolk and polyvinyl pyrrolidone hydrogel, as well as their composition in various percentages, were studied on Lactobacillus plantarum. The best sample from the first phase was selected, and it was combined with skim milk in various percentages in the second phase of the experiment, and the effect was analyzed. Statistical analysis was performed by the SPSS method. The highest survival effect was obtained with skim milk (SR=۹۵/۲%). SEM images of cryoprotectant surfaces were acquired.CONCLUSIONThe main evaluation criterion of this study was the statistical analysis. As seen in the statistical figure ۳-۱, in the first phase, sample number ۲ has the highest survival rate in the first phase. The control sample, which had no cryopreservation, had the lowest survival rate. Each substance's impact was nearly equivalent and similar to one another. The best result is obtained when PVP is mixed with egg yolk and the amount of egg yolk is less than the amount of PVP. Sample ۳, in which each ingredient was used equally, was particularly noteworthy. This indicates that these Substances do not overlap well in equal proportions . It can be stated that both egg yolk and PVP have been shown to considerably protect Lactobacillus plantarum from FD damage. But Skim milk performed significantly better than the OS in the second stage. Skim milk is a combination of simple carbohydrates and protein and the amount of fat in it is too low. But egg yolk has a high amount of fat, but its carbohydrate and protein levels are lower than skim milk. PVP is a chemical that is made by strong hydrogen bonds with phenolic, hydroxyl, and carboxyl groups. It has previously been proven that compounds containing proteins and carbohydrates have a higher cryoprotective effect. In this study, skim milk was selected as the best ingredient for a cryoprotectant during FD for the Lactobacillus plantum bacteria.

کلیدواژه ها:

Probiotic ، Lactobacillus plantarum ، Freeze-drying ، Lyophilization ، Cryoprotectant ، Egg yolk ، Polyvinyl pyrrolidone ، Skim milk