Effect of electron beam irradiation on some characteristics of xanthan with emphasis on application in foliar fertiliser production

Abstract

Irradiation-induced chain scission is known as a useful tool for degrading polysaccharides into smaller-sized and lower-molecular-weight fragments or even producing oligo-saccharides that have improved bioactivities. This study aimed to investigate the properties of radiation-degraded xanthan for further application in the production of foliar fertiliser. The xanthan solutions of 2% were electron beam (EB) irradiated at 10, 20, 30, and 50 kGy doses, with dose rates of 1.5, 3.5, and 7.5 kGy/s. The study parameters include the effects of irradiation dose and dose rate on certain properties of xanthan in solution. Results showed the viscosity and molecular weight of xanthan significantly decreased with the increases in radiation dose and dose rate. EB irradiation seemed not to introduce the changes in the xanthan structure, though UV-Vis and FT-IR spectra both revealed the absorption peaks corresponding to the carbonyl group increased with radiation dose due to the formation of C=O double bonds during radiation degradation. The resulting degraded xanthan fragments showed higher mobilities for crystallisation, so their crystallinity degree and melting temperature also increased.