Activity and Stability of Biofilm Uricase of Lactobacillus plantarum for Uric Acid Biosensor

Workshop and International Seminar on Science of Complex Natural Systems

Iswantini, Dyah^1 ; Rachmatia, Rescy^1 ; Diana, Novita Rose^1 ; Nurhidayat, Novik^2 ; Akhiruddin^3 ; Saprudin, Deden^1

Department of Chemistry, Faculty of Mathematics and Natural Sciences, Bogor Agricultural University, Bogor

16680, Indonesia^1

Division of Microbiology R and D for Biology, Indonesian Institute of Sciences, Bogor, Indonesia^2

Department of Physics, Faculty of Mathematics and Natural Sciences, Bogor Agricultural University, Bogor

16680, Indonesia^3

关键词: Extreme environment;    Glassy carbon electrodes;    Lactobacillus plantarum;    Optimum conditions;    Planktonic bacteria;    Structured communities;    Substrate concentrations;    Uric acid biosensors;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/31/1/012028/pdf
DOI  :  10.1088/1755-1315/31/1/012028

来源: IOP

【 摘 要 】

Research of uric acid biosensor used a Lactobacillus plantarum was successfully conducted. Lactobacillus plantarum could produce uricase that could be used as uric acid biosensor. Therefore, lifetime of bacteria were quite short that caused the bacteria could not detect uric acid for a long time. To avoid this problem, development of biofilm for uric acid biosensor is important. Biofilms is a structured community of bacterial cells, stick together and are able to maintain a bacteria in an extreme environments. The purpose of present study was to determine and compare the activity of uricase produced by L. plantarum, deposited whithin biofilm and planktonic bacteria on glassy carbon electrode (GCEb & GCE), also to determine the stability of biofilm. The optimization process was conducted by using temperature, pH, and substrate concentration as the parameters. It showed that the activity of uricase within biofilm was able to increase the oxidation current. GCEb and GCE yielded the oxidation current in the amount of 47.24 μA and 23.04 μA, respectively, under the same condition. Results indicated that the optimum condition for uric acid biosensor using biofilm were pH 10, temperature of 40oC, and uric acid concentration of 5 mM. The stability of GCEb decreased after 10 hours used, with decreasing percentage over 86.33%. This low stability probably caused by the unprotected active site of the enzyme that the enzyme is easier to experience the denaturation.