Abstract
Wastewaters generated from various stages of edible oil production in a canola processing facility were collected with the aim of determining the presence of lipase-producing actinobacteria of potential industrial significance. The high chemical oxygen demand (COD) readings (up to 86,700 mg L−1 in some samples) indicated that the wastewater exhibited the nutritional potential to support bacterial growth. A novel approach was developed for the isolation of metagenomic DNA from the oil-rich wastewater samples. Microbiota analysis of the buffer tank and refinery condensate tank wastewater samples showed a dominance of Cutibacterium acnes subsp. defendens, followed by a limited number of other actinobacterial genera, indicating the presence of a highly specialized actinobacterial population. Cultured isolates with typical actinobacterial morphology were analyzed for their ability to produce lipases and biosurfactants. Two strains, designated as BT3 and BT4, exhibited the highest lipase production levels when grown in the presence of tributyrin and olive oil (1.39 U mg−1 crude protein and 0.8 U mg−1 crude protein, respectively) and were subsequently definitively identified by genome sequencing to be related to Streptomyces albidoflavus. Cultivation of the strains in media containing different types of oils did not markedly increase the level of enzyme production, with the exception of strain BT4 (1.0 U mg−1 crude protein in the presence of peanut oil). Genome sequencing of the two strains, BT3 and BT4, revealed the presence of a range of lipase and esterase genes that may be involved in the production of the enzymes detected in this study. The presence of gene clusters involved in the production of biosurfactants were also detected, notably moreso in strain BT3 than BT4.
Highlights
Over the past one and a half centuries, numerous publications have focused on the enzyme lipase
The main aim of this study was to determine whether wastewater generated in the canola oil industry could potentially serve as a source of lipolytic actinobacteria, especially since similar studies mostly focused on olive mill wastewater [63,64,65,66]
An analysis of the physicochemical properties of the wastewater showed that suitable macronutrients that would support the growth of microorganisms are found in wastewater generated in the canola oil industry
Summary
Over the past one and a half centuries, numerous publications have focused on the enzyme lipase (triacylglycerol-acyl-hydrolase; EC 3.1.1.3). This ubiquitous enzyme is produced by animals, plants, and microorganisms and catalyzes the hydrolysis of glycerol-esters (notably long-chain acylglycerols vs short-chain acylglycerols hydrolyzed by esterases) for the release of diacylglycerols, monoacylglycerols, and free fatty acids [1,2,3]. It is often found that organisms with the ability to produce lipases produce surface active compounds [4]. These amphipathic compounds show activity at interfaces by lowering the tension between them: surfactants reduce surface tension at the air–water interface, while emulsifiers reduce the surface tension between two immiscible liquids. With the need for more ‘green’ processes to drive the global bioeconomy, as well as consumer
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
