3.5.1.75	additional information	crosslinked enzyme aggregates of Providencia rettgeri urease (PRU-CLEAs) are prepared using genipin as crosslinking agent, method, overview. Optimal at 0.3 g/l of bovine serum albumin. The aggregates remove urea, but the treatment with PRU-CLEAs reveals no significant change of volatile flavor substances in Chinese rice wine. By using urea as the substrate, the values of Km and Vmax of free urease from Providencia rettgeri JN-B815 are estimated to be 5.99 mmol/l and 840 nmol/min, while those of immobilized urease are 13.54 mmol/l and 940 nmol/min, respectively. By using urethane as the substrate, the Km and Vmax value of free urethanase are determined to be 183.82 mmol/l and 970 nmol/min, while those of immobilized enzyme are 705.78 mmol/l and 650 nmol/min, respectively	-, 754024	
3.5.1.75	additional information	development of an amperometric biosensor for ethyl carbamate (urethane) with urethanase and glutamate dehydrogenase (GLDH). Urethanase decomposes ethyl carbamate to produce ammonia, which is converted to L-glutamate under the catalysis of GLDH in the presence of 2-oxoglutarate and NADH. The two enzymes are entrapped into chitosan/gelatine/gamma-glycidoxy propyl trimethoxy silane sol-gel and immobilized on the surface of pyrolytic graphite electrode (PGE). The modified electrode is characterized by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Under the optimized conditions, the amperometric EC biosensor exhibits a linear detection range from 0.0005 to 0.040 mM with a low detection limit of 5.30 nM. The biosensor is successfully used to detect urethane in mimic Chinese rice wine samples, and satisfactory recovery and relative standard deviation are achieved	-, 753406