稻秆木素侧链13C同位素示踪及固体13CNMR分析

在水稻(Oryza sativa L.)生长过程中,向其茎秆部节间的空腔分别注入在侧链α,β,γ位带有¹³C标记的松柏醇葡萄糖甙,得到¹³C标记的稻秆木素,用高分辨率固体核磁¹³CNMR对其组织进行分析,发现外源性的松柏醇葡萄糖甙并不影响水稻中木素的正常合成.证明了β-O-4,β-β,β-5和β-1结构是稻秆原本木素中的主要结构,另外还有少量的松柏醇和阿魏酸类结构,并证实木素在α位与糖类等组分有共价键形成.

Carbon-13 Enrichment of Rice Stalk Lignin Traced by Solid State 13C NMR Spectroscopy

Carbon-13 enrichment of specific carbon of rice stalk lignin was achieved by feeding coniferin- α-¹³C], coniferin- β-¹³C] and coniferin- γ-¹³C] into an internode cavity of the stalk of a growing rice plant(Oryza sativa L.). The resulting rice stalk tissues were analyzed by high-resolution solid state carbon-13 nuclear magnetic resonance (¹³C NMR) spectroscopy. It was found that the administration did not affect the normal ligninfication of rice plant. It was also proved that β-O-4, β-β, β-5 and β-1 were mainly a substructure in protolignin of rice stalk although there were some minor substructures as coniferyl alcohol and ferulic acid unit. Importantly, the result indicated that significant bonding occurred at α-position to other constituents, presumed to be mainly of carbohydrates.