A new peroxidase from garlic (Allium sativum) bulb: its use in H(2)O(2) biosensing

作者：El Ichi Sarra; Abdelghani Adnane; Hadji Imene; Helali Salwa; Limam Ferid; Marzouki M Nejib^*

来源：Biotechnology and Applied Biochemistry, 2008, 51: 33-41.

DOI：10.1042/BA20070141

• amperometric measurement
• biosensor
• garlic (Allium sativum) peroxidase
• gelatin matrix
• gold electrode
• hydrogen peroxide (H(2)O(2))

Peroxidase POX(I) isoenzyme was purified from garlic (Allium sativum L.) bulb by ammonium sulfate precipitation, gel filtration and anion-exchange chromatography. Native-PAGE profile showed two isoforms, designated POX(IA) and POX(IB). POX(IB) seems to be more attractive for biosensor design since its K(m) (app) for H(2)O(2) is lower than that of POX(IA). In addition to its storage and operational stability, POX(IB) was found to be highly heat-stable, since almost 70 of its activity was conserved at 60 degrees C, whereas full activity was retained at 50 and 40 degrees C for 40 min. The optimal pH was approx. 5 and the optimal temperature was 30 C. Next, gelatin was used as a matrix for enzyme immobilization on a gold electrode surface and electrochemical measurements were performed by using cyclic voltammetry. POX(IB)-based electrodes show great potential for application in H(2)O(2) monitoring of biological samples.

• 出版日期2008-9