title: In-situ chemical analyses of trans-polyisoprene by histochemical staining and Fourier transform infrared microspectroscopy in a rubber-producing plant, Eucommia ulmoides Oliver.
abstract: The localization of polyisoprene in young stem tissues of Eucommia ulmoides Oliver was investigated by histochemical staining and Fourier transform infrared (FT-IR) microspectroscopy. The fibrous structures were stained with Oil Red O. FT-IR microspectroscopic analysis proved that the fibrous structures were trans-polyisoprene. Granular structures stained with the dye, and characteristic absorptions at 2,960 cm(-1) and 1,430 cm(-1) in FT-IR suggested that trans-polyisoprene accumulated in the vicinity of the cambium layer. We have thus successfully shown for the first time the localization of trans-polyisoprene in plant tissues, and our histological investigation allowed us to presume the main sites of biosynthesis and accumulation of trans-rubber. Furthermore, a new technical approach, the preparation of sections using an electronic freezing unit and the in situ analysis of polyisoprene using FT-IR microspectroscopy, is demonstrated to be a promising method for determining the accumulation of polyisoprene as well as other metabolites.
mesh_terms: D001391:Azo Compounds / Q000737:chemistry; D002070:Butadienes / Q000378:metabolism*; D031283:Eucommiaceae / Q000737:chemistry* / Q000378:metabolism; D045782:Hemiterpenes; D006651:Histocytochemistry / Q000379:methods*; D010420:Pentanes; D024301:Plant Bark / Q000737:chemistry / Q000378:metabolism; D018515:Plant Leaves / Q000737:chemistry / Q000378:metabolism; D018547:Plant Stems / Q000737:chemistry / Q000378:metabolism; D012408:Rubber / Q000378:metabolism*; D017550:Spectroscopy, Fourier Transform Infrared / Q000379:methods*
chemical_list: D001391:Azo Compounds; D002070:Butadienes; D045782:Hemiterpenes; D010420:Pentanes; C005059:isoprene; D012408:Rubber; C011049:oil red O