Research of activity and thermal stability of GOD in jujube and buckwheat honeys

The activities of glucose oxidase in jujube and buckwheat honey of different geographical sources were determined.Jujube honey from Jiaxian,Shanxi Province and buckwheat honey from Xichang,Sichuan Province had the highest glucose oxidase activity with the value of( 0.161 ± 0.002) U / g and( 0.112 ± 0.001) U / g,respectively. The activity of GOD in Lvliang,Shanxi jujube honey samples was only( 0.007 ± 0.001) U / g,and the lowest activity appeared in buckwheat honey from Jinbei,Shanxi Province with the same value.The results showed that the GOD activity varied significantly between different botanical and geographical sources of Chinese unifloral honey.Furthermore,thermal stability of GOD in these two honey samples was detected. The result showed that with increasing of temperature,the activity of GOD in jujube was reduced and there was no activity when the temperature up to 70℃ with 90 min. Under the same conditions,the activity of GOD still can be determined in buckwheat honey.This research indicated that the thermal stability of buckwheat honey was higher than jujube honey.