茯苓,是擬層孔菌科真菌茯苓的乾燥菌核,常寄生在松樹根上,形如甘薯,球狀,外皮淡棕色或黑褐色,內部粉色或白色,精製後稱為白茯苓或者雲苓。作為一種常用的傳統中藥,茯苓除在利尿、抗菌、抗腫瘤等方面有應用以外尚被廣泛應用於食品添加劑和糕點、茶點等的製作中。茯苓的主要化學成分有多糖、三萜(主要為羊毛甾烷型和3,4-裂環羊毛甾烷型)及麥角甾醇等。其中三萜成分具有多種生物活性(如細胞毒、抗氧化、抗癌等)且為苦味相關成分。
中國科學院成都生物研究所公共實驗技術中心的研究人員與上海中醫藥大學教授徐宏喜研究團隊合作,開發出茯苓中三萜成分檢測的超高效液相色譜-二極體陣列-飛行時間質譜(UPLC–PDA–QTOF–MS)方法,基於此方法,可有針對性地對茯苓中已知和未知三萜化合物進行鑑定,極大程度地簡化譜圖,去除其他共有化合物的幹擾。研究人員在將該方法應用於40個採自中國不同地區的茯苓樣品的分析中,對茯苓中檢測出的31個主要三萜化合物進行了鑑定並利用統計學方法對這些茯苓樣品的相似性和差異性進行了研究。研究結果表明,來自不同產地的茯苓樣品,其三萜成分的種類和含量有很大差別。依三萜成分的相似性可以將茯苓樣品劃分為三大群組,研究人員對造成這些茯苓群組差異的化學成分進行了鑑定,為茯苓樣品的產地追蹤提供標誌化合物。該方法可快速、準確、全面地鑑定茯苓中的已知和未知三萜成分,在茯苓及茯苓產品的質量控制、風味評價及真偽鑑定中獲得應用。
該研究成果發表於Food Chemistry,2014,152:237-244。 (生物谷Bioon.com)
生物谷推薦的英文摘要:
Food Chemistry
Advanced ultra-performance liquid chromatography-photodiode array-quadrupole time-of-flight mass spectrometric methods for simultaneous screening and quantification of triterpenoids in Poria cocos.
Xia B1, Zhou Y2, Tan HS3, Ding LS1, Xu HX4.
A sensitive, precise and accurate method was developed to screen and quantify triterpenoids based on ultra-performance liquid chromatography-photodiode array-quadrupole time-of-flight mass spectrometry (UPLC-PDA-QTOF-MS). An exact neutral loss scan of 62.0004 Da (CH2O3) was used to selectively detect triterpenoids in Poria cocos, followed by a survey scan for exact masses of precursor and fragment ions of these triterpenoids. The developed method was applied to quantify seven major triterpenoids in 40 P. cocos samples of different origins within 18 min, and a total of 31 triterpenoids were unequivocally or tentatively identified. Principal component analysis of these samples showed a clear separation of three groups, and ten triterpenoids play key roles in differentiating these samples were obtained from the OPLS-DA variable influence on projection (VIP) plot and then unequivocally or tentatively identified. The developed method can be applied for rapid bitterness evaluation, quality control and authenticity establishment of P. cocos.