三种巨大口蘑菌株贮藏期间褐变及相关酶活性

以巨大口蘑SCAU1、新3和新4三种菌株子实体为试材,于12℃和相对湿度95%下贮藏,定期取样测定褐变度、多酚氧化酶(PPO)、酪氨酸酶(TYR)、漆酶和总酚等生理指标,研究各菌株的褐变度与酶活性及总酚的相关性。结果表明,贮藏期间三种巨大口蘑菌株的褐变度呈上升趋势,PPO、TYR及漆酶的活性均呈下降趋势,其中SCAU1菌株的褐变度和PPO、TYR及漆酶活性最低,而总酚含量与新3和新4差异不显著(p>0.05);相关性分析结果显示,新3、新4菌株的褐变度均与PPO活性呈极显著负相关(p<0.01),SCAU1菌株的褐变度与PPO活性呈显著负相关(p<0.05),相关性从高到低依次为新3菌株>新4菌株>SCAU1菌株,此外,新3菌株的褐变度与TYR活性呈显著负相关(p<0.05)。该结果可为巨大口蘑优良菌株的选育和褐变内在机理的揭示提供依据。

Browning and the Activity of Related Enzymes of Three Tricholoma giganteum Strains during Storage

Fruit bodies of freshly harvested Tricholoma giganteum strains SCAU1,Xin3 and Xin4 were used as experimental materials and stored at 12℃ with relative humidity of 95%,and the browning degree,polyphenol oxidase(PPO),tyrosine(TYR),laccase and total phenol were measured regularly,the correlation between browning degree and enzyme activity of each strain was investiged. The results showed that the browning degree of three strains was increased,the activity of PPO,TYR and laccase showed the downward trend. The browning degree,PPO,TYR and laccase activities of SCAU1 strain were lower than xin3 and xin4 strains,but the total phenol content in the three was hot significantly different(p>0.05);correlation analysis showed that the browning degree of xin 3 and xin 4 strains was extremely significantly negatively correlated with PPO activity(p<0.01),the browning degrce of SCAU1 strain was significantly negatively correcolted with PPO activity(p<0.05),the correlation from high to low was the Xin3,Xin4,SCAU1,and the browning degree of Xin3 strain was also significantly negatively correlated with the activity of TYR(p<0.05). This results could provide some theoretical guidance for the breeding of excellent strains of Tricholoma giganteum and revealing the intrinsic mechanism of browning.