Optimization Of Enzymatic Hydrolysis Of Phycocyanin And Inhibitory Activity Of Hydrolysate To Obesity-related Enzymes

In this paper, the strains of Spirulina were selected out by determining the contents ofprotein and amino acid firstly. Then, phycocyanin was obtained by salt precipitation afterthe cells were broken by the repeatedly freezing-thaw and ultrasonic wave cracking method.Finally, technological process was determined by optimization of enzymatic hydrolysis tostudy the effect of hydrolysate on the activity of obesity-related enzymes. The resultsprovided the theoretical basis of spirulina and it’s phycocyanin for medical treatment andhealth care. The main results were as follows:1. Screening of spirulina strainsThe strain40sY grew faster and had higher ratio of protein (58.62%) and amino acid,of which the total amino acid and the essential amino acid relative content were50.21mg/100mg and38.69%, respectively, under the culture conditions of9000lx lightintensity,12h/12h light dark cycle,30℃/28℃day and night temperature. Compared withthe anti-obesity peptides reported, the proportions of the amino acid were the highest inarginine (8.14%), histidine (1.81%), proline (2.66%) and leucine (9.23%).2. Obtaining of phycocyanin anti-obesity enzymolysis productsThe neutral protease which had the optimalizing effect assessment (43.89%) wasselected out from alkaline protease, papain and trypsin based on the inhibitory activityeffect to Pancreatic lipase. The optimum hydrolysis conditions that the hydrolysate hasinhibition activity effects on porcine pancreas lipase and α-amylase porcine pancreas lipaseand α-amylase were temperature47℃, pH7, hydrolysis time4.5h, enzyme dosage118U/mL. The inhibitory rate of porcine pancreas lipase and α-amylase were53.88%and36.21%, respectively.3. Testing of effects of phycocyanin hydrolysate on the activity of obesity-relatedenzymesEnzymolysis products of phycocyanin could inhibit activities of porcine pancreaslipase and α-amylase and it was a dose-dependent relationship. The inhibition was morepowerful when the concentration of enzymolysis products increased.The inhibitory rate toporcine pancreas lipase and α-amylase were62.15%and46.89%, respectively when theconcentration ran up to10mg/mL.It also had a certain dose relationship between the dosesof phycocyanin’s enzymolysis produects. That was enzymolysis products could reducecholesterol micellar solubility. When the concentration increased to15mg/mL, the inhibitrate of solubilities of cholesterol micelle in vitro human biliary was57.09%.