Abstract: Objective: The serum levels of superoxide dismutase (SOD), lactate dehydrogenase (LDH), malondialhyde (MDA) and glutathione (GSH) in cold-stressed mice were measured to discover whether kombucha enhances cold tolerance in mice. Methods: Twenty male CD-1(ICR) mice were randomly divided into 4 groups of 5 mice each: control group, sugary green tea infusion group, kombucha group I and kombucha group II, which were administered intrasgatrically with normal saline, sugary green tea infusion, culture supernatant from fermented sugary green tea infusion, and culture supernatant from fermented synthetic medium for 30 consecutive days at the dosage of 1 mL once a day, respectively. After the last administration, 0.2 mL of blood from the mice of each group were collected for the determination of serum SOD, LDH, MDA and GSH levels before and after the mice were kept in a cold chamber at 10 ℃ for 3 h. Results: The SOD levels of the two kombucha groups before and after the cold stress increased highly significantly compared with the control group (P＜0.01), whereas the MDA levels showed a highly significant downward trend (P＜0.01). GSH level revealed a highly significant increase (P＜0.01) in the kombucha group I both before and after the cold stress and in the kombucha group II only after the cold stress. Both the groups showed a significant decrease in LDH level (P＜0.01) after the cold stress. Conclusions: Both the kombucha groups rather than the control group or sugary green tea infusion group can enhance cold tolerance in mice. The kombucha group I is superior to the kombucha group II.

Key words: kombucha, cold tolerance, superoxide dismutase (SOD), lactate dehydrogenase (LDH), malondialhyde (MDA), glutathione (GSH)