Isolation and characterization of irradiated and ultrasonicated degradation products of kappa-carrageenan

• Main Author: Tecson, Mariel G.
• Format: text
• Language: English
• Published: Animo Repository 2020
• Subjects: Irradiation; Ultrasonics; Chemistry
• Online Access: https://animorepository.dlsu.edu.ph/etd_masteral/5954; https://animorepository.dlsu.edu.ph/context/etd_masteral/article/13013/viewcontent/Tecson_Mariel_G_11889616_ISOLATION_AND_CHARACTERIZATION_OF_IRRADIATED_Partial.pdf
• Institution: De La Salle University

The production of low molecular weight kappa-carrageenan by irradiation technique has shown to enhance plant growth and stimulate defense mechanism in rice plants. This study embarked on investigating the structural changes in the κ-carrageenan as the irradiation dose increases. Using the optimized dose, the active molecular fragment of irradiated κ-carrageenan was isolated through alcohol precipitation, dialysis, and HPLC techniques. The semi-pure fragments were characterized using UV- Vis, FT-IR, and NMR spectroscopies. Structural changes of κ-carrageenan at absorbed doses 10 and 20 kGy were monitored and the structural fragments of the degraded κ- carrageenan at these doses were proposed to account for the observed spectroscopic data. Ultrasonication of κ-carrageenan was also conducted and optimized to achieve molecular weight suitable for plant growth promotion. ID and 2D NMR analysis afforded structural fragment that accounts for the degradation of κ-carrageenan under ultrasound treatment. Further studies are recommended to synthesize the proposed fragments and investigate its effect on plant growth. Keywords: Aged irradiated κ-carrageenan, PGP, ultrasonicated κ-carrageenan,