Journal of Bacteriology & Parasitology

Lipolytic enzymes of Geobacillus sp. 95: potential for industrial application

46^th World Congress on Microbiology

September 18-19, 2017 Dublin, Ireland

Vilius Malunavicius, Alisa Gricajeva, Egle Lastauskiene, Mikas Sadauskas, Audrius Gegeckas and Renata Gudiukaite

Vilnius University, Lithuania

Posters & Accepted Abstracts: J Bacteriol Parasitol

Abstract:

Geobacillus species show high potential as biocatalysts suitable for industrial biotechnology applications. The ability of these bacteria to produce a variety of extracellular enzymes, such as amylases, xylanases, proteases, lipases, esterases and ureases has ranked them among the most important enzyme producers. Thermostable and thermoactive lipolytic enzymes have gained remarkable importance over other industrially used biocatalysts due to their versatility regarding catalytic behavior. The main advantages of performing industrial processes at higher temperatures are reduced risk of microbial contamination and lower viscosity. It was showed that Geobacillus sp. strain 95 produces two types of thermostable, thermoactive and organic solventtolerant lipolytic enzymes: lipases (named GD-95) and carboxylesterases (named GDEst-95). The main goal of this research was to investigate the potential of recombinant variant of GD-95 lipase and GDEst-95 esterase for the application in industry. It was shown that both enzymes displayed an ability to perform catalysis at temperatures ranging from 5oC to 75°C while retaining more than 50% of lipolytic activity after incubation at temperature range of 30-65oC. Both biocatalysts also possessed long-term (216 h) stability in isopropanol, methanol and hexane (25% and 50%). Our results also showed that new esters can be obtained using a mixture composed of coconut, peach, macadamia or canola oils, 1/10 (w/w) ethanol or methanol and GD-95 lipase as biocatalyst. The major ingredient of coconut oil is lauric acid which can be turned into ethyl laureate (flavour ingredient) via esterification reaction with ethanol. The results also suggested that GD-95 lipase can be a powerful tool for the production of emulsifiers (mono- or diacylglycerols). In conclusion, the present study demonstrated that lipolytic enzymes (lipase and carboxylesterase) produced by Geobacillus sp. strain 95 have suitable properties for industrial applications and can offer an eco-friendly alternative for chemical synthesis.

Biography :

Vilius Malunavicius is currently an MSc student in Microbiology and Biotechnology at the Institute of Biosciences in Vilnius University. He has 4 years of experience working in Protein Engineering field for lipolytic enzymes improvement. He is as co-author of a publication and several conference theses, associated with lipolytic enzymes from Geobacillus sp. 95. He has also received Prof. K Jankevicius Scholarship (2016) and worked at Greifswald University Prof. U T Bornscheuer group under the Erasmus program for 3 months (2017.02-2017.05).