Abstract:
In search of green technology, enzyme production has received much attention in industrial biotechnology processes with the objective of the substitution of chemical processes, with potentially adverse effects on humans and environment. Protease enzyme has been utilized widely in industries to engender a wide range of products such as, detergent, leather, waste management, brewing, meat softening, milk-clotting, food, pharmaceutical, cancer treatment, diagnostics, digestion, viral disorders and silver recovery. Therefore the present study was aimed to examine enzymatic and antimicrobial properties of protease from papaya (Carica papaya L.) Leaf, seed and fruit pulp. Enzyme extraction was conducted 10 mM Tris-Hydrochloride (Tris-HCl) buffer at pH 8.0 and 2MNaCl for three hours on an orbital shaker. The protein content was determined using Lowry assay using bovine serum albumin (BSA) as a standard protein. The optimum activity of the protease enzyme was done using PH and temperature. The antimicrobial activities of the enzyme extract were arranged as 3x4 completely randomized designed (CRD) factorial design in three replications. The result indicated that enzymatic extracts of papaya (Carica papaya L.) leaf, seed and fruit pulp presented significantly the highest protein content for leaf sample (11.67mg/ml). Significantly the highest protease activity was recorded for fruit pulp extract (42.28 U/ml). The optimum pH for protease activity was 7.5. The effect of incubation temperature on protease activity demonstrated that the maximum protease activity was observed at 350C. The strongest antibacterial activity with maximum zone of inhibition (17.50mm) at highest concentration (200mg/ml) of the enzyme extract was recorded for leaf enzyme extract against S. aureus. On xvi the other hand, the strongest antifungal activity with maximum zone of inhibition (18.50mm) was recorded for leaf extract against A. niger. The C. papaya leaf enzyme extract has exhibited strongest bactericidal activity with minimum inhibitory concentration (MIC 2.34mg/ml) and the corresponding minimum bactericidal concentration (MBC, 4.69 mg/ml) for leaf enzyme extract against S. aureus indicating that S.aureus was more susceptible than E. coli. Antifungal activity, the papaya leaf extract has presented strongest antifungal activity with MIC (4.69 mg/ml, the least value) and minimum fungicidal concentration (MFC, 7.81 mg/ml) against A. niger showing that A. niger was more susceptible to the enzyme extract than C. albicans. . It can be concluded that papaya enzyme extract has wide range of antimicrobial activities with the leaf extract with greatest antimicrobial potential while seed enzyme extract presented the least antimicrobial potential.