Studies On Influence Factor And Existing Fome Of Formaldehyde In Lentinula Edodes

Lentinus edodes is a kind of anticancer mushroom.But Formaldehyde in Lentinus edodes keep it out of international market.Forming mechanism. Influence factor and existing form of Formaldehyde in Lentinus edodes was researched in the present paper.What is combined with Formaldehyde in Lentinus edodes according to simulated experiment. The inheriting effect of Lentinus edodes and Formaldehyde was compared. The results indicated:(1) Activity ofγ-glutamyl transpeptidase and C-S Lyase in different mushroom was compared to ensure that Formaldehyde was metabolized in Lentinus edodes,γ-glutamyl transpeptidase and C-S Lyase participate in the reaction. pH 7.0,37℃Activity ofγ-glutamyl transpeptidase is3.62. pH 9.0, 37℃. Activity of C-S Lyase is 2.38.(2) The optimum pH and temperature ofγ-glutamyl transpeptidase is 7.0, 37℃. Activity ofγ-glutamyl transpeptidase can be stimulated by Ca²⁺. Cu²⁺,Pb²⁺,Zn²⁺ was inhibitors. Most of amino acid served as stimulator besides leucin and glycin.(3) The optimum pH and temperature of C-S Lyase is alkalescency, 37℃. Activity of C-S Lyase can be stimulated by Mg²⁺,Ca²⁺,Cu²⁺,Pb²⁺.Zn²⁺ was inhibitors.L- Cysteine, praline and glycin served as inhibitors.(4) Formaldehyde in different part of Lentinus edodes was determine by Acetylacetone spectrophotometer. The content of Formaldehyde was according to activity ofγ-glutamyl transpeptidase and C-S Lyase.(5) Different form of Formaldehyde was determine by Acetylacetone spectrophotometer. Dissociated and combined Formaldehyde was separated by distillation with acid or not. Content of Combined-Formaldehyde in total Formaldehyde is 71.7～74.6%. Content ration of Dissociated and combined Formaldehyde is 34.1%～39.5%。(6) Formaldehyde can be combined by protein and amylase in the Lentinus edodes.Content of Formaldehyde combined in protein and amylase were 71.6 mg/kg and 229.9mg/kg.Combination of Formaldehyde and protein is not affected by pH, temperature and time. While the content of combined Formaldehyde is increased during outside Formaldehyde enhanced. Combination of Formaldehyde and amylase is not affected by temperature, optimum pH is 7.0. Content of combined Formaldehyde is decreased during time extended and increased during outside Formaldehyde was enhanced.(7) Micronucleus effect of Lentinus edodes and Formaldehyde was conducted using micronucleus test technique with Vicia faba root tip. The result showed that that frequency of micronucleus of Lentinus edodes were lower that of control group. In Formaldehyde group, the frequency of micronucleus showed significantly dose—dependent increase. This may be indicated that Formaldehyde has potential of mutagenic activity.(8) Effect of Lentinus edodes and Formaldehyde on mutagenicity were conducted with Ames test. The mutagenicity of Lentinus edodes and Formaldehyde groups were no more than 2 times that of the control group. No mutagenicity was observed in this study.(9) Content of Formaldehyde in Lentinus edodes was reduced from 7.70mg/kg to 4.13 mg/kg, 3.71mg/kg to 1.70mg/kg , 11.82mg/kg to 5.25mg/kg when Lentinus edodes was dipped 30 min, cooked 25 min and fried 4min.