This study was conducted to examine morphological characteristics and the content of cell wall polysaccharides of Brassica campestris var. pekinensis(baechu). First of all, the variety of scientific name and naming of parts of baechu in the literatures of kimchi showed, which will unify marks. So, we propose not so much mid-rib and leaf blade of baechu leaf as white part and green part, respectively. On the other hand, the forms of vessel elements of white part in baechu consist in ring, sclariform and reticulate thickening. The proximate compositions and contents of cell wall polysaccharides of baechu has significant differences between its cultivars. The cell wall pectin from baechu exhibited four peals with molecular weights of 2,000,000, about 100,000 and less than 10,000 by gel filteration chromatography and hemicellulose did two peaks with molecular weights of 2,000,000 and 10,000.

This study was conducted to understand the characteristics of fruit softening during ripening which causes deep loses in quality of horticultural products during storage and marketing process after harvest. The changes of cell wall components during ripening was investigated. The climacteric rise was between 42 and 49 days after anthesis and then decreased. Ethylene evolution was similar to respiration. The hardness of fruit decreased markedly at this climacteric period and significances of textural parameters among the ripening periods were recognized but the significance between 50 and 55 days after anthesis was not. Sugar components of cell wall polysaccharides were uronic acid, galactose, glucose, arabinose, xylose, rhamnose, mannose and fucose. The contents of arabinose and mannose in alcohol-insoluble solids fraction increased, but other sugars were not changed. In cell wall fraction, the contents of uronic acid, galactose, glucose and arabinose were comparatively high, but galactose, arabinose and ironic acid were decreased markedly during ripening. ironic acid occupied above 75% of total monosaccharide in pectin fraction and decreased markedly during ripening. In acid-soluble hemicellulose fraction, the contents of uronic acid, glucose, galactose and rhamnose were high and they decreased from 50 days after anthesis. The contents of glucose and xylose were high in a alkali-soluble hemicellulose fraction and they decreased markedly at 55days after anthesis.