The synthesis of carboxymethyl polysaccharide from Arenga pinnata Merr. endosperm and sodium chloroacetate with microwave irradiation

Carboxymethyl polysaccharides of Arenga pinnata endosperm (APE) seeds can be synthesized directly without the addition of water through the reaction between soft and hard APE polysaccharides with chloroacetate using NaOH solution under irradiation of microwaves for 5 minutes. Firstly the soft and hard APE were crushed. Next the etherification process using NaOH solution and sodium chloro acetate reagent in 96% ethanol was conducted with a ratio of sodium chloro acetate and NaOH used was 1.95: 2.6 (w/w) and in soft and hard APE seeds. The carboxymethyl polysaccharides of soft and hard APE seeds obtained have brown color and were analyzed by spectrophotometer FT-IR, X-RD and SEM. The formation of carboxymethyl polysaccharides was characterized by the appearance of absorption bands in the wavenumber area of 1729 cm-1 which indicates the presence of C = O stretching vibrations from carboxymethyl. The degree of substitution obtained by the titration method is between 1.58 - 1.86. The X-RD results show that the hard and soft carboxymethyl APE seeds are amorphous and the intensity of the carboxymethyl polysaccharides of the soft APE seeds is lowers than from the hard APE and the degree of substitution is lower. The surface morphology of hard APE is finer than soft APE seeds.