How dehydration with glycerol protects bacteria cell membranes against deleterious effects of supercooling

The need for novel cryoprotectants and cryopreservation protocols: Insights into the importance of biophysical investigation and cell permeability

“…[59][60][61][62][63]68] The effects of penetrating cryoprotectants on membranes have been less widely studied, with most attention being given to DMSO and glycerol. [58,[69][70][71][72][73][74][75] CPAs may bind to the cell membrane, either the polar or non-polar region depending on the chemical composition of the CPA. [69] Some CPAs can protect membranes from phase transition damage by inhibiting fusion e.g.…”

Interactions of cryoprotective agents with phospholipid membranes - A Langmuir monolayer study

“…Several studies have been carried out to understand the membrane protection effects of natural CPAs such as sugars, especially disaccharides, and the mechanisms are becoming clearer 6,[10][11][12][13] . The mechanisms of action of penetrating cryoprotectants have been less widely studied, with the exception of dimethyl sulphoxide (DMSO) and glycerol [14][15][16][17][18][19][20][21] . However, these molecules are toxic to cells and cryopreservation involves balancing these two effects 5 .…”

Thermodynamic Properties and Water States in Ternary PVP/Lactose/Water Frozen Systems

“…They are commonly added to the formulation before starting the freezing step in the case of systems with living microorganisms such as vaccines and probiotics. The penetrating agents are small molecules which can diffuse through the membrane cells, reduce the risk of intracellular ice crystal formation, and prevent damage to the cells. , On the other side, the nonpenetrating agents present two main properties: first, because of their large, long chain molecules, they cannot penetrate the cells and they increase the osmolarity of the extracellular phase, preventing intracellular dehydration and intracellular crystallization. Second, they have the ability to be adsorbed on the bacterial surface, allowing water vitrification around the cells, preventing osmotic shock and slowing down the rehydration kinetics. − …”