To reveal the possible mechanism of silica deposition in higher plants, lignin was isolated from rice straw following a modified method to conduct a simulation experiment in vitro. UV and infrared absorption spectra s...To reveal the possible mechanism of silica deposition in higher plants, lignin was isolated from rice straw following a modified method to conduct a simulation experiment in vitro. UV and infrared absorption spectra showed that the substance had the unique characteristics of pure lignin. The presence of silicon in the precipitation was revealed by TEM (transmission electron microscopy) with EDXA (energy dispersive X-ray analysis) device. It was found that in the borax solution where lignin precipi-tation occurred silica-lignin co-precipitation was produced but not in the DMSO solution where lignin was broken into its com-position compounds and did not precipitate. This means that it is macromolecular lignin itself but not its compounds that could induce silica deposition in higher plants.展开更多
Lignin is a group of phenolic polymers which is abundant in the woody tissues of vascular plants,and is essentially absent from all other living organisms.It has therefore been accepted as a tracer for terrestrial org...Lignin is a group of phenolic polymers which is abundant in the woody tissues of vascular plants,and is essentially absent from all other living organisms.It has therefore been accepted as a tracer for terrestrial organic carbon(TOC) in marine environment since the 1970s.Lignin polymers are not amenable to direct chemical analysis without prior isolation.This review focused on the methods of chemical decomposition,extraction,derivatization and detection of lignin in marine environment.We described and compared several chemical decomposition methods,including nitrobenzene oxidation,alkaline cupric oxide(CuO) oxidation and thermochemolysis,and detection methods such as gas chromatography(GC),gas chromatography-mass spectrometry(GC-MS),high performance liquid chromatography(HPLC) and so on.Possible improvement of lignin analysis and the application prospects of this tracer were also discussed.展开更多
基金Projects supported by the National Natural Science Foundation of China (No. 30170550), the Natural Science Foundation of Anhui Provincial Education Department (No. 2005kj398zc) and the Culture Project for "the Tenth Five-year" Learning Leaders of Higher School of Anhui Province, China
文摘To reveal the possible mechanism of silica deposition in higher plants, lignin was isolated from rice straw following a modified method to conduct a simulation experiment in vitro. UV and infrared absorption spectra showed that the substance had the unique characteristics of pure lignin. The presence of silicon in the precipitation was revealed by TEM (transmission electron microscopy) with EDXA (energy dispersive X-ray analysis) device. It was found that in the borax solution where lignin precipi-tation occurred silica-lignin co-precipitation was produced but not in the DMSO solution where lignin was broken into its com-position compounds and did not precipitate. This means that it is macromolecular lignin itself but not its compounds that could induce silica deposition in higher plants.
基金supported by National Basic Research Program of China (973 Program 2010CB428901)
文摘Lignin is a group of phenolic polymers which is abundant in the woody tissues of vascular plants,and is essentially absent from all other living organisms.It has therefore been accepted as a tracer for terrestrial organic carbon(TOC) in marine environment since the 1970s.Lignin polymers are not amenable to direct chemical analysis without prior isolation.This review focused on the methods of chemical decomposition,extraction,derivatization and detection of lignin in marine environment.We described and compared several chemical decomposition methods,including nitrobenzene oxidation,alkaline cupric oxide(CuO) oxidation and thermochemolysis,and detection methods such as gas chromatography(GC),gas chromatography-mass spectrometry(GC-MS),high performance liquid chromatography(HPLC) and so on.Possible improvement of lignin analysis and the application prospects of this tracer were also discussed.