Comparison of light microscopy and spatially resolved fourier transform infrared (FT-IR) microscopy in the examination of cell wall components of strawberries

Abstract

Different chemical components and their location in strawberry achene, vascular bundles and cortical cell walls were studied by means of bright-field microscopy using different staining systems and by Fourier transform infrared (FT-IR) microscopy and the two methods were compared. For bright-field microscopy, pectin, protein, lignin and cellulose were stained with specific staining systems. For FT-IR microscopy, the spectra of commercial pectin, protein, lignin and cellulose were measured in the 4000-700 cm-1 region and compared to spectra obtained from the different strawberry tissues. Both methods showed that lignin was an important component of achene and vascular bundles, whereas the cortical cell walls contained mainly pectin and cellulose in the middle lamella, and protein as deposits in the outer layer. The structure of all the cell walls was complicated and consisted of several components. The two methods used gave comparable results. ©1998 Academic Press.