Optimization of the production conditions of the lipase produced by Bacillus cereus from rice flour through Plackett-Burman Design (PBD) and response surface methodology (RSM).
In this study, the screening of lipase positive bacteria from rice flour was carried out by Rhodamin B agar plate method. Bacillus cereus was identified by 16S rDNA method. Screening of the appropriate variables and optimization of the lipase production was performed using Plackett-Burman design (PBD) and response surface methodology (RSM). Among the isolated bacteria, an aerobic Bacillus cereus strain was recognized as the best lipase-producing bacteria (177.3 ± 20 U/ml). Given the results, the optimal enzyme production conditions were achieved with coriander seed extract (CSE)/yeast extract ratio of 16.9 w/w, olive oil (OO) and MgCl2concentration of 2.37 g/L and 24.23 mM, respectively. In these conditions, the lipase activity (LA) was predicted 343 U/mL that was approximately close to the predicted value (324 U/mL), which was increased 1.83 fold LA compared with the non-optimized lipase. The kinetic parameters of Vmaxand Kmfor the lipase were measured 0.367 μM/min.mL and 5.3 mM, respectively. The lipase producing Bacillus cereus was isolated and RSM was used for the optimization of enzyme production. The CSE/yeast extract ratio of 16.9 w/w, OO concentration of 2.37 g/L and MgCl2concentration of 24.23 mM, were found to be the optimal conditions of the enzyme production process. LA at optimal enzyme production conditions was observed 1.83 times more than the non-optimal conditions. Ultimately, it can be concluded that the isolated B. cereus from rice flour is a proper source of lipase.
Department of Food Science and Technology, Ferdowsi University of Mashhad, P.O. Box, 91775-1163, Mashhad, Iran.
Alireza
A
Vasiee
Department of Food Science and Technology, Ferdowsi University of Mashhad, P.O. Box, 91775-1163, Mashhad, Iran.
Behrooz Alizadeh
BA
Behbahani
Department of Food Science and Technology, Ferdowsi University of Mashhad, P.O. Box, 91775-1163, Mashhad, Iran. Electronic address: tabatabai@um.ac.ir.
Farideh Tabatabaei
FT
Yazdi
Department of Food Science, Engineering & Technology, Faculty of Agricultural Engineering and Technology, University of Tehran, Tehran, Iran. Electronic address: samiramoradi@alumni.ut.ac.ir.
Samira
S
Moradi
D000332:Aerobiosis; D001409:Bacillus cereus / Q000145:classification / Q000201:enzymology* / Q000254:growth & development / Q000302:isolation & purification; D001431:Bacteriological Techniques; D003470:Culture Media / Q000737:chemistry; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D005433:Flour / Q000382:microbiology; D007700:Kinetics; D008049:Lipase / Q000378:metabolism*; D008403:Mass Screening; D012275:Oryza / Q000382:microbiology; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA
D003470:Culture Media; D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D012336:RNA, Ribosomal, 16S; D008049:Lipase
16s rDNA; Bacillus cereus; Lipase; Plackett-burman design; Response surface methodology (RSM)