Evaluation of activity and stability of laccase produced by native Aspergillus strain isolated from olive oil waste

Subject Areas : Industrial Microbiology

Fatemeh Kheirollahi ¹ (Ph.D Student, Department of Microbiology, School of Basic Sciences, Rasht Branch, Islamic Azad University, Rasht, Iran)
Masoumeh Anvari ² (Department of Microbiology, School of Basic Sciences, Rasht Branch, Islamic Azad University, Rasht, Iran)
mahdi Shahriarinour ³ (Department of Microbiology, School of Basic Sciences, Rasht Branch, Islamic Azad University, Rasht, Iran)
shahab Shariati ⁴ (Department of Chemistry, School of Basic Sciences, Rasht Branch, Islamic Azad University, Rasht, Iran)

Received: 2021-02-28 Accepted : 2021-08-16 Published : 2021-08-23

Keywords: Enzymatic activity, Lacasse, Aspergillus spp, olive oil waste,

Abstract :

Background & Objectives: Laccases are enzymes that belong to the group of oxidases that have different applications in various industries. The aim of this study was to evaluate the activity and stability of the laccase enzyme produced by a native Aspergillus spp. isolated from olive oil waste. High inducer phenolic compounds content of these wastes is main reason of their selection as substrate.  Materials & Methods: In this study, 12 different fungal strains were isolated from olive oil wastes and the best strains with the highest enzyme activity was selected as the best strain and was     identified based on phenotypic and genotypic characterization. Enzyme purification was           performed using dialysis and zymographic analysis methods. Finally, the effect of various       physic-chemical factors such as incubation time (6-216 h), temperature (20-40 C) and pH (5, 6, 7 and 8) on the enzyme stability and activity was evaluated. Results: The results showed that the best productive strain belongs to the genus Aspergillus spp. The highest enzyme activity was observed at 30 °C (1.57 IU/ml), pH = 6 (1.86 IU/ml) and after 6 days (1.53 IU/ml). Stability studies showed that the enzyme activity was stable for 6 minutes at  30-35 °C and pH = 6-7 and about 90% of the enzyme activity was maintained under the above conditions. Conclusion: The laccase enzyme with significant activity and stability produced by a native strain of Aspergillus spp. isolated from olive oil waste due to its high activity and stability can be an  acceptable candidate for industrial use.