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Various cell wall polysaccharides such as ionically associated pectin (IAP), covalently bounded pectin (CBP), 4N potassium hydroxide soluble hemicellulosic fraction (HF₁) and 0-3N soluble hemicellulosic fraction (HF₂) were fractionated from crude cell wall of the fresh and soft persimmon by chemical method. The changes in cell wall polysaccharides were studied by gel filteration chromatography. The content of crude cell wall remarkably decreased in the soft persimmon. The decreasing rates of IAP, CBP and HF, were 59, 60 and 74%, respectively, while HF, and cellulose changed only a little during softening. Sugar compositions of IAP and CBP were 72-84% uronic acid, 5-11% hexose and 11-16% pentose, and also the hemicellulose was composed of uronic acid besides hexose and pentose that was hemicellulosic components. The loss rate of pentose in IAP, of hexose in CBP, of hexose and uronic acid in HF₂, of pentose in HF₁, increased during softening. Though apparent average molecular weight of all polysaccharides shifted from high molecular weight to low molecular weight polymer, the shifting degree of CBP and HF₂, was especially remarkable during softening. It is suggested that the severe softening phenomenon of persimmon involved the degradation and dissolution of wall bound-CBP and HF₂ which were associated with each other.
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