Separation and Purification of Agarase and Study on Its Properties
XIE Xi-zhen;LIN Juan;XIE Yong;YE Xiu-yun;Fujian Provincial Key Laboratory of Marine Enzyme Engineering,Fuzhou University;
Agarase was fermented with Vibrio sp. ZC-1,and separated through hollow fiber concentration,ammonium sulfate precipitation and DEAE-anion exchange chromatography. A pure Aga ZC-1 detected by SDSPAGE was obtained. Its relative molecular mass and specific activity was about 45 k Da and 114. 613 U / mg,respectively. Furthermore,the enzymatic properties of Aga ZC-1 were studied. The results showed that the optimum p H was 7. It was stable in the range of 5. 0 to 9. 0 and could maintain more than 80% of its relative enzyme activity after incubation for 1 hour. The optimal reaction temperature was 50℃ and 60% of enzyme activity was remained after incubation for 1 hour under 45℃. At high concentrations( 5mmol / L),Fe~(3 +),Cu~(2 +),Sn~(2 +)and Zn~(2 +)could completely inhibit the enzyme activity. While at low concentrations( 1mmol / L),Cu~(2 +),Ba~(2 +),Na~+,Zn~(2 +),Ag~+,Sr~(3 +)and K~+had obvious inhibition on enzyme activity. The Kmand Vmaxof Aga ZC-1was 0. 538 mg / ml and 6. 33μmol /( L·min),respectively. It was highly specific for agar and the hydrolysates were neoagarotetraose and neoagarohexaose analyzed by TLC.