Chorisia speciosa

The floss silk from Chorisia speciosa furnished a polysaccharide with a main chain of (1 -> 4) linked P-Xylp substituted at 0-2 by 5 % of uronic acid. The xylan structure also was interposed with a-Rhap units in small amounts. The defatted seeds furnished on aqueous extraction a major fraction, ((9-acetyl, 10 % and protein, 45 %) wich was hydrolysed and analysed by p.c. and GLC, showing Rha (20 %), Ara (16 %), Gal (64 %) and also uronic acids (45 %). Partial hydrolysis gave rise to a polysaccharide free of arabinose, with 46 % of uronic acids. Methylation analysis (GLC -MS) indicated a chain of (1 4) - linked Gal/ (42 % of 2,3,6-Me3-Gal). 

This paper reports the structural features of the silk floss polysaccharide and the partial structure of a viscous acidic polymer obtained from the seeds of Chorisia speciosa. It was of interest to analyze these polysaccarides due to the relationship of Bombacaceae to Sterculiaceae, as well as for its possible commercial uses. 

Plant material. The fruit of Chorisia speciosa at mature stage was collected from large trees in parks of Curitiba. 

Table III. NMR Data for the Xylan (PI) from the floss silk of Chorisia speciosa.

Chorisia speciosa HBK-269 Chrysophyllum lacourtiomtm De Wild.—263 Clavaria truncata Quelet—147 Clavicepspaspali Stevens et Hall-148,155, 158-9,437... 

Chorisia speciosa Humboldt, Bonpland et Kunth (McKenna etal. 1986) Quararibea ishpingd (Arevalo "Valera 1986 Y5 iss6n 1979)... 

C,8H3oO,7 518.425 Constituent of the gum exudate of Chorisia speciosa (Bombacaceae). 

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