灵芝子实体多糖积累和糖代谢相关酶的关系研究

Studies on the Correlation Between Polysaccharides Accumulation and Sugar Metabolizing Enzymes in Ganoderma lucidum

分析灵芝子实体生长过程中多糖、还原糖及糖代谢相关酶活性变化,探讨灵芝子实体多糖动态变化的酶学机理。以代料栽培灵芝为试材,采用苯酚-硫酸法测定灵芝多糖含量,采用DNS法测定还原糖含量,测定6种相关糖代谢酶活性,并用SPSS17.0统计软件分析多糖积累与糖代谢酶间的相关性。在灵芝子实体生长过程中,灵芝多糖与还原糖含量变化趋势相同,两者的最大含量皆出现在开伞期;从现蕾期到开伞期,多糖积累与6种糖代谢酶活性变化趋势一致,但开伞期之后,多糖与G-6-PDH、MDH酶活性变化趋势出现差异。经过相关性分析,UDPGP Plase、α-PGM和PGI与灵芝多糖积累呈现显著的正相关(P<0.05),其他酶与灵芝多糖积累相关性不显著(P>0.05)。初步推测,UDPGP Plase、α-PGM和PGI是灵芝多糖合成的关键酶。

In order to study the enzymatic mechanisms responsible for polysaccharides synthesis,the changes of polysaccharides,reducing sugar and metabolism-related enzymes in developing G.lucidum were analyzed.The contents of polysaccharides and reducing sugar were determined with phenol-sulfuric acid method and DNS method,respectively.The activities of six kinds of sugar metabolism-related enzymes were assayed.The correlation between polysaccharides accumulation and sugar metabolism-related enzymes was analyzed with SPSS 17.0.The change tendency of G.lucidum polysaccharides and reducing sugar changed similarly.The maximum content of polysaccharides and reducing sugar appeared in pileus phase.The polysaccharides accumulation was consistent with the change tendency of activities of six kinds of metabolism-related enzymes from the budding phase to the pileus phase,but not with that of G-6-PDH and MDH after the pileus phase.The content of polysaccharides had significant positive correlations with the activities of UDP-glucose pyrophosphorylase （UDPGPPlase）,α-phosphoglucomutase （α-PGM） and phosphoglucose （PGI）.However,there were not significant correlations between polysaccharides and the activities of hexokinase （HK）,malate dehydrogenase （MDH） and glucose-6-phosphate dehydrogenase （G-6-PDH）.UDPGPPlase,α-PGM and PGI played the important role in the biosynthesis of G.lucidum fruiting body polysaccharides.