MICROSCOPIC STUDIES OF THE TISSUE STRUCTURE OF KONJAC TUBERS

The tissue structures of 2-year-old konjac tubers were investigated us ing a variable pressure scanning electron microscope equipped with an energy-dispersive X-ray spectrometer and an optical microscope. Konjac mannan (KM) cells are distributed all over the tuber and the spaces b etween the KM cells are filled with parenchyma. The KM cells are cover ed with scale-like cell walls and the size of the cells varies from 16 0 to 650 mu m. Other kinds of particles with different sizes are obser ved in the honeycombed cells around the KM cells. The small grains rel ate to protein granules and the spherical particles (similar to 12 mu m in diameter), which are composed of small granules (1-3 mu m in diam eter), are starch. The tuber also contains potassium and calcium in th e parenchyma. Most calcium is found in the needle-like crystals in the form of calcium oxalate. Such crystals are also found in I year and s eed tubers.