Improved cryopreservation by diluted vitrification solution with supercooling-facilitating flavonol glycoside

Area of Science:

• Plant Biotechnology
• Cryopreservation
• Biochemistry

Background:

• Vitrification solution (VS) toxicity and ice nucleation limit successful cryopreservation.
• Kaempferol-7-O-glucoside (KF7G) is a potent supercooling-facilitating flavonol glycoside.
• Deep supercooling in plants is facilitated by flavonol glycosides like KF7G.

Purpose of the Study:

• To assess the efficacy of diluted vitrification solution (VS) for cryopreservation.
• To investigate the role of KF7G in reducing cryoprotectant toxicity and inhibiting ice nucleation.
• To improve cryopreservation success rates for plant shoot apices.

Main Methods:

• Cranberry shoot apices were treated with diluted Plant Vitrification Solution 2 (PVS2) at 75% and 50% concentrations.
• KF7G was added at 0.5 mg/ml to diluted PVS2 treatments.
• Cryopreservation was achieved through vitrification, followed by cooling and rewarming.

Main Results:

• Undiluted PVS2 caused severe injury and no regrowth.
• Diluted PVS2 reduced toxicity but led to poor regrowth due to ice nucleation.
• Addition of KF7G to diluted PVS2 significantly increased regrowth rates (p<0.05) by inhibiting nucleation and promoting vitrification.

Conclusions:

• Diluted vitrification solutions supplemented with KF7G can overcome cryopreservation limitations.
• KF7G facilitates vitrification by inhibiting ice nucleation, enabling reduced cryoprotectant concentrations.
• This strategy holds potential for successful cryopreservation of diverse biological materials.