The influence of plant oil on the production of lipases enzyme from Staphylococcus aureus isolated from imported cheeses

Abstract

Milk and dairy products are very important as food sources. However, they are usually contaminated with
members of the genus Staphyloccocus especially that liberate lipolytic enzymes. Thus the goals of this research
were the, production of lipolytic enzymes at 37₀C and 20₀C by Staphyloccocus aureus that isolated from
imported cooked cheese, lipases enzymes activity screened at different plant oils, activation or inhibition of
lipase production using different plant oils. Rhodamine B agar, tween 80 agar and Baird- Packer containing
sodium tolerite agar were used for the detection of lipase, esterase and lecithinase enzyme respectively. Lipase
enzyme was estimated by titration method using olive oil as a substrate. The results showed that fourteen
isolates representing to 70% were lipase and lecithinase producer they gave orange florescence color on the
top of rhodamine B plate and turbid zone on bed parker telurite agar respectively, while esterase enzyme could
detected from only two isolates that represented to 10 %. The production of lipase and esterase was depended
on me and temperature, both enzymes secreted a er 18 h incubated at 37₀C and 72h at 20₀C; their activity
were increased with time to reach the maximum ac vity a er 72h at 37₀C and 96h at 20₀C. The best lipase
producing isolate was S. aureus KK1; its lipase was more active in hydrolyzing garlic oil followed by fingureek
and castor oils at both 37₀C and 20₀C. The results cleared that castor oil, tween 80 and seasam were supported
maximum lipase production which reached to 23.3, 20 and 13.2 U ml-1 respec vely a er 48 hr in compares with
6 U/ml produced at nutrient broth. Otherwise inhibition of lipase production recognized among other plant
oils, from wheat germ 3.5 to mint 0.33U ml-1.