| 摘要 |
FIELD: chemistry.SUBSTANCE: method includes centrifuging alkali-treated seaweed extract at 70-80°C at 10000-14000 rpm for 5-15 minutes; mixing the hot extract with 2-5% surfactants at a temperature in the range of 60-100°C while stirring continuously and allowing settling for 1-10 hours at a temperature in the range of 25-35°C to precipitate the solid agarose mass; decanting the supernatant liquid and washing said mass with water to remove residual surfactants in the solid substance; redissolving the obtained wet mass in a minimum amount of water in the range of 7 to 10% (wt/wt) with respect to the weight of the agarose product and treating with a minimum amount of isopropanol. The ratio of the amount of the agarose sol to the isopropanol is in the range of 1:0.5 to 1:1.5 (wt/wt) for agarose precipitation. Further, the solid product is isolated and dried in a suitable drier to obtain agarose powder. The obtained agarose powder matches the mesh size according to the American standard in the range of 200 to 300. The seaweed used is selected from Gracilaria and Gelidiella species, preferably Gracilaria dura and Gelidiella acerosa of Indian Ocean water obtained from the Gujarat and Tamil Nadu coasts. Said surfactant is a nonionic surfactant and is selected from commercially available octyl phenol ethoxylate (Triton X-100) and nonyl phenol ethoxylate (Synperonic 91/6) Said surfactant induces flocculation only when the content of sulphate in agarose is <0.82% (wt/wt), preferably <0.5% (wt/wt) and even more preferably <0.25%.EFFECT: invention enables to obtain agarose of high quality and reduces power and labour consumption of the method.7 cl, 3 dwg, 5 tbl, 28 ex |
