STM Article Repository

Vegetable oils are harmful to the environment, like petroleum oils they produce similar environmental
effects. Hence, it is a known fact that the olive oil causes the production of large quantity of olive mill
waste (OMWs) as by-products to the environment. These by-products are harmful to the environment,
both terrestrial and aquatic. Bacteria are very useful in protecting the environment. The lipolytic
activities of physiologically diverse bacteria have great potential to degrade oil spills in the
environment. Fatty acids are the major components of lipids; and the physical, chemical and
physiological properties of a lipid class depend primarily on its fatty acid composition. There is need
for extensive characterisation of the bacterium lipase for the treatment of vegetable oil-polluted sites.
This work was carried out to preliminarily characterise the lipase of Pseudomonas fluoresens and to
check the fatty acid composition of olive oil. Gas chromatography method can be used for the
identification of microbiological degraded fatty acids in vegetable oils as methyl ester.
Pseudomonas fluoresens was screened for lipase production using standard methods. Temperature,
pH, ion concentration (NaNO3 and MgSO4), enzyme concentration, nitrogen concentration, substrate
concentration, time course and agitation speed were optimised for the lipase activity as well as
growth.
Crude enzyme of Pseudomonas fluoresens had the highest lipase activity and growth of 0.8 U/mL and
1.418 mg/mL respectively at room temperature, but when production was optimised higher activity 0.9
U/mL was seen in the use of glucose as substrate. Agitation with the speed used did not support
lipase production but supported growth (1.998 mg/mL) at agitation speed of 100 rpm. Olive oil
degraded by lipase of Pseudomonas fluorescens grown in two different Mineral Salt Medium, was
studied over 25 days. Olive oil was analyzed for fatty acids commonly present in olive oils which are
Myristic, Palmitic, Stearic, Oleic, Linoleic, Linolenic, Behenic and Lignoceric, which have specific
carbon number and their values in approximate percentage are C14:0 (0.4), C16:0 (14.0), C18:0 (5.5),
C18:1 (76.4), C18:2 (3.4), C18:3 (0.1), C22:0 (0.1) and C24:0 (0.1) respectively. Oleic acid
percentage is high in olive oil which contained considerable amount of 76.4%.
The reduction of fatty acid by Pseudomonas fluorescens after 20 days was 8.2% in the media used.
Lipase from Pseudomonas fluorescens had potential for degradation of fatty waste. It could therefore
be employed in environmental cleanup of oil spill site. Lipase production is generally influenced by the
type and concentration of carbon and nitrogen sources, the culture pH, the growth temperature and
the dissolved oxygen concentration [1]. Hence monitoring the result of degradation patterns of the
vegetable oil using fatty acid methyl ester analysis, by Pseudomonas fluorescens, showed that this
organism has great potential for fatty waste degradation and as an extension in environmental clean
up of oil spill site.