Free rhamnose (Rha) and arabinose (Ara) in the mango exudate
(SAPNDM) were quantitated by analogy. However, in this case, an
aqueous SAPNDM solution containing 7.5 g L1 was membranefiltered
(0.45 mm) and directly injected (25 mL). Furthermore, the
HPAEC-PAD conditions were adapted to separate free fucose (Fuc),
galactose (Gal), glucose (Glc), sucrose (Suc), xylose (Xyl), mannose
(Man), and fructose (Fru) at 25 C and a flow rate of 0.3 mL min1
after injecting 25 mL of SAPNDM solutions containing 3.75 or
0.075 g L1. For this purpose, a modified gradient profile based on
Zheng, Thayer, Rao, and Pohl (2009) was used as follows (relative to
the injection at 0 min): 500 mM NaOH from 15.0 min
to 14.0 min, 2.5 mM NaOH from 13.9 min to 24.9 min, and
500mMNaOH from 25.0 min to 35.0 min. To ensure the removal of
concomitant polysaccharides from the column, a blank (water) was
injected after each SAPNDM injection, and the column was washed
excessively after every fourth sample injection. For SAPNDM, the
contents of bound neutral-sugar residues were calculated by subtracting
the free neutral sugars from the ANS