Studies On Fractions Of Agar

As one of three most industrial gums extracted from marine algae, agar is applied in the fields of food, medicine, biologic technique, paper making and etc. First, studies on Gelidium amansii agar fractionation are carried out in this thesis. Gelidium amansii agar is fractionated on the DEAE-Celluiose and four fractions are obtained sequentially. The obtained fractions are submitted to chemical analysis, IR and ?C-NMR spectroscopic study for elucidating their chemical structures. Among the four obtained fractions, water fraction measures up to the standard of low EEO agarose. Its sulfate contents is 0.16%, its gel strength is 1130 g/ cm 2(1% gel), its electroendosmosis (EEO) is 0.12, which are similar to Sigma product抯. Since sulfate contents of 2.Smol/L NaCl fraction and I .OmoiIL NaCl fraction are high, which are 22.804 and 32.5%. they are named as agaropectin. Low gel point agarose is necessary in the application of agarose, especially in the field of biologic technique. The studies of preparation of low gel point agarose by methylation reaction are carried out, using water fraction of Gelidium amcinsii agar as raw material. A modified agarose containing alkylated agarose measures up to the standard of low gel point agarose. Its gel strength is 264 g/ cm 2(1% gel), its gel point is 30.1C (1. 5% gel), its melting temperature is 64.8C (1. 5% gel), which are similar to Sigma product. Pharmacology of agaropectin on anticoagulation in vitro and vivo are studied. The results show that agaropectin can effectively prolong the coagulation time of blood plasma by 3.125mg/mI, 6.25 mg/mI, 12.5mg/mi, 25mg/mi in vitro; TT, CT, PT, KPTT can be effectively prolonged after ig 100mg/kg, 200mg/kg, 400mg/kg in mice for 15 days; the Fib level in blood plasma can be significantly lowered after continuous ig in mice for 15 days.