基于分子古生物学的藏药渣驯形成机制研究

Brag-zhun is a long-used traditionnal Tibetan medicine. There was great argument about the source of Brag-zhun in the academic world, which was the key issue of restricting the establishment of its quality standards and rational use. The preliminary investigation and experiment have indicated that Brag-zhun is a mixture of organic-rich black material seeping from rock stratum and animal feces.While the carbon14 dating manifested that organic matter in rock stratum is not a modern product.The above results show inconformity with current viewpoints such as mineral hypothesis,feces hypothesis and so on.Based on all above evidences, this study brought out ‘fossil sources hypothesis’for the organic matter in rock stratum of Brag-zhun. Then clarify its formation mechanism from three aspects: "Geological background surveying–Biomarker evidence searching– Animal defecation behavior observation".3S technology will be conbined with geological mining exploration in order to clarify the geological environment in where the organic matter could forming or gathering. Evidences of the key biomarkers will be looked for by several analysis methods such as FT-IR,13C NMR, pyrolysis mass spectrometry, HPLC-MS,GC-MS and so on. Then clarify the reason of organic matter and faeces coexistence. This study is a radically reform for origin of Brag-zhun, which will essentially reveal the formation cause of it. It aslo has important significance for establishment of quality standards of Brag-zhun, and promote its resources protection and rational use.

渣驯是传统藏药，用药历史悠久，关于渣驯的基源问题学术界争论激烈，是制约渣驯质量标准建立与合理利用的关键问题。前期调查及实验表明，渣驯是由岩层中渗出的富含有机质的黑色物质与动物粪便的混合物，碳14测年表明岩层中有机质非近代产物，上述结果与“矿物说”、“粪便说”等观点均有矛盾。基于上述证据，本课题提出渣驯岩层中有机质“生物化石来源”假说，从“地质背景勘测-生物标志物证据探寻-排便动物行为观察”三个方面阐明渣驯形成机制: 勘查出露点地质环境，阐明有机质富集（或形成）的地质环境；采用FT-IR、碳13核磁共振、热解质谱法、HPLC-MS、GC-MS等分析方法寻找具有指标性的关键生物标志物证据，推测岩层内有机质的生物来源与形成环境；阐明岩石中流出的有机物与粪便共存的原因。本研究是对渣驯的正本清源，将从本质上揭示渣驯药材的成因，对于制定渣驯质量标准、推动渣驯资源保护与利用具有重要意义。

渣驯，为大宗常用藏药，主要用于治疗诸热症，特治胃、肝、肾热症，如木布病、肝中毒、眼病等。渣驯来源论点多样，且现有理论、假说均不能合理阐释渣驯来源。本研究基于渣驯形成机制假说，采用地质调查法、化学分析法以及分子古生物学研究，分析渣驯有机碳的地质环境背景、化学结构特征和生物来源，初步阐明渣驯形成机制；同时，对渣驯小分子部位进行成分分离和HPLC-MS分析，分析成分与其形成间的关系。. 研究结果如下：所调查的渣驯出露点地层分布在三叠系新都桥组（T3xd）、扎尕山组+杂谷脑组（T2-3zg-z）、侏倭组（T3zh）、盐塘组（T1-2y）等；出露区岩性特征主要表现为板岩、炭质板岩、砂质板岩、千枚岩、变砂岩、灰岩；渣驯背景岩石矿物组分主要为长英质、绢云母、石英。渣驯背景岩石出现3种孔隙发育，包括粒间孔发育、溶蚀孔洞发育、裂缝与节理发育。背景岩石有机碳含量较高，其与渣驯、粪粒代用品无机元素含量无显著差异性。元素分析结果表明，渣驯主要是低成熟的新鲜有机质组成，渣驯的C/N比值较低，反映了渣驯中藻类和微生物的贡献；CP/MAS 13C NMR研究结果表明，渣驯的官能团主要为脂肪碳和与氧相连的脂碳，而芳香类基团含量较低，与海洋（水生）腐殖质结构相似，提示渣驯中可能有海洋（水生）腐殖质的贡献；PY-GC-MS结果表明，渣驯裂解产物主要是木质素类化合物、含N化合物及脂肪酸类化合物。反映了渣驯中藻类和细菌等的明显输入。此外，渣驯裂解产物中木质素类化合物含量较高，且存在2-甲氧基苯酚，表明渣驯中有裸子植物的贡献。