BioChem - DOS

New alkaline lipase from Rhizomucor variabilis: Biochemical properties and stability in the presence of microbial EPS

Biotechnology and applied biochemistry

Bancerz, Renata; Osiń ska‐ Jaroszuk, Monika; Jaszek, Magdalena; Janusz, Grzegorz; Stefaniuk, Dawid; Sulej, Justyna; Janczarek, Monika; Jarosz‐ Wilkołazka, Anna; Rogalski, Jerzy

<P><B>Abstract</B></P><P>A new strain of <I>Rhizomucor variabilis</I> producing an active extracellular lipase was identified and characterized in the present studies. The culture conditions were optimized and the highest lipase production amounting to 136 U/mL was achieved after 4 days of cultivation. The optimum pH (5.5) and temperature (28 &deg;C) were determined as the best conditions for <I>R. variabilis</I> lipase production. The isolated enzyme preparation exhibited maximum activity at 40 &deg;C and pH 8.0. Lipase from <I>R. variabilis</I> was stable up to 50 &deg;C during 2 H retaining 80% of its initial activity. The enzyme was highly stable in the pH range of 7.0&ndash;9.0. Moreover, the addition of naturally obtained exopolysaccharides (EPS) significantly enhanced lipase activity. The presence of EPS derived from <I>Ganoderma applanatum</I> and <I>Rhizobium leguminosarum</I> enhanced the lipase activity, which was 22% and 31%, respectively, higher than that in the control experiments. Simultaneously, the pH activity profiles remained unchanged. The Michaelis&ndash;Menten constant and the turnover number of the enzyme for <I>p</I>&#8208;nitrophenyl palmitate in the standard assay conditions were estimated at a level of 0.631 mM and 0.674 Sec<SUP>&minus;1</SUP>. In conclusion, the results obtained in this work present a newly isolated lipase preparation stabilized with EPS or without modification as a very effective tool for industrial application.</P>

2016

0885-4513

63

1

pp.67-76

10.1002/bab.1351

http://click.ndsl.kr/servlet/OpenAPIDetailView?keyValue=05787966&target=NART&cn=NART79036830

lipase; Rhizomucor variabilis; enzyme stability; exopolysaccharides