Comparision research on the cell wall-breaking methods of lactic acid bacteria

This study aims to explore a rapid, efficient and economical method for breaking lactic acid bacteria cell wall. Five different methods including glycine treatment, repeated freezing and thawing, lysozyme digestion, zirconia beads disruption, ultrasonic treatment and three composite wall-breaking methods were used to treat Lactobacillus.plantarum 1.557 cells, respectively.And gram staining and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) were used as evaluation method to analyze the difference of cell wall-breaking effects and time costs. In addition, the activity of protein extracted by zirconia beads method was tested by the β-glucuronidase (GUS) assays.The quality of RNA extracted by zirconia beads method was tested by agarose gel electrophoresis. Results showed that zirconia beads method was better than other methods, the GUS protein extracted by this method had the activity of protein.The OD₂₆₀/OD₂₈₀ ratio of RNA extracted by this method was between 1.8 and 2.1, which was in accordance with the standard ratio, and the purity was high and the degradation degree was low.Therefore, the zirconia beads method was a fast, efficient and economical method for rapid extraction of lactic acid bacteria bacterial protein and total RNA.