Table II.

Sequential extraction of Ca²⁺, B, and pectic polysaccharides from radish root cell walls

Sample	Ca2+	B	Pectic Polysaccharidesa	2-Keto-3-Deoxysugarsb
Crude cell walls	100  (13)c	100  (0.25)	100 (25)	100 (1.0)
SDS-treated cell walls	2	83	78  ± 0.4	90  ± 2.8
SDS- and CDTA-treated cell walls	0	5	29  ± 2.1	34  ± 0.7
SDS-, CDTA-, and alkaline-CDTA-treated cell walls	–d	–	14  ± 0.5	29  ± 2.8

^aDetermined by the m-hydroxydiphenyl method using GalUA as a standard. 

^bDetermined by modified thiobarbituric acid method using 3-deoxy-d-manno-2-octulosonic acid as a standard. 

^cValues in the parentheses are μmol Ca²⁺, μmol B, μmol 2-keto-3-deoxysugars, and mg uronic acid g⁻¹ crude cell walls. 

^d–, Not determined.