Manufacture of water soluble low-molecular alginates by ultrasonication pretreatment and hot water extraction

摘要

PURPOSE: A method for preparing water-soluble low molecular alginic acid is provided, by using the ultrasonic pretreatment and the hydrothermal extraction to reduce the processing steps and to reduce the viscosity and molecular weight of obtained alginic acid. CONSTITUTION: The method comprises the steps of: suspending a brown seaweed powder and a sea tangle powder in distilled water which is 75 times volume of powder and placing it at a room temperature for 30 min; treating it by using an ultrasonic wave at a temperature of 20-50 deg.C for 30-120 min; adding distilled water which is 75 times volume of powder into the solution and heating it at a temperature of 95 deg.C for 60 min to carry out the hydrothermal extraction; filtering it by using celite 545 or centrifuging it at 5,000 rpm for 10 min; adding methanol into the obtained extract to collect the precipitated alginic acid; washing the collected alginic acid; and drying the washed alginic acid at a temperature of 40 deg.C.