Mountain Top University Library

ABSTRACT
The increasing interest in the development of lipase is attributed to the possible biotechnological applications of these enzymes. Lipases are hydrolytic enzymes that have occupied a major role as commercial biocatalysts in hydrolyzing triglycerides to free fatty acids and glycerol. Microorganisms isolated from restaurant wastewater polluted soil were screened for fungal lipase production on solid agar. Morphological and biochemical characteristics of the best isolate were investigated. The effect of carbon sources including monosaccharide (glucose), disaccharide (sucrose), polysaccharide (starch) and agro wastes (plantain peel, banana peel, starch, wheat bran and rice bran) and nitrogen sources were investigated. A total of twelve (12) fungi were isolated. There was significant difference (p≥0.005) in growth and lipase activity on solid medium. The diameter of growth ranged from 23.0k – 53.0a mm while lipase activities ranged from 2.0g – 10.5a mm. Isolate TPD1 identified as Trichoderma harzianum gave the best mycelium growth and activity. Lipase production using different carbon sources ranged from 88.96e – 156.42a U/mL. Glucose (156.42a U/mL) supported the highest lipase production followed in order by sucrose (132.21b U/mL), mannitol (129.44c U/mL) and plantain peel (104.65d U/mL) while the least production was recorded in rice bran (85.56g U/mL). Lipase production using organic and inorganic nitrogen sources ranged from 88.96e – 128.01a U/mL peptone supported the highest production (128.01a U/mL) while Urea provided the least support (88.96e U/mL). The study has shown that Trichoderma harzianum TPD1 isolated from wastewater polluted soil is a potential lipase producer and can be harness for industrial production.
Key words: lipase production, carbon source, lipase, nitrogen source, solid state fermentation (SSF), Trichoderma harzianum.