World Journal of
Pharmaceutical and Life Sciences

ROLE OF POLYGALACTURONASE FROM ASPERGILLUS FUMIGATUS ITCC 6915 IN THE IMPROVEMENT OF TEA QUALITY

Akhilesh Thakur, Rutika Sehgal, Anupam Lakhanpal and Reena Gupta*

ABSTRACT

Background and Objective: Polygalacturonases are most extensively studied among the family of pectinolytic enzymes. Of late, microbial source of these enzymes has gained importance. In the current study, the effect of purified polygalacturonase on the improvement of tea quality was investigated and different contents namely theaflavin, thearubigin, highly polymerized substances and total liquor color found in tea were quantified in order to check the effect of crude enzyme preparation and purified polygalacturonase on the improvement of tea leaves’ fermentation. Materials and Methods: Fungal isolate producing polygalacturonase was isolated and characterised by 18S rDNA sequencing. The isolate was identified as Aspergillus fumigatus ITCC 6915. The enzyme was purified by DEAE-cellulose anion exchange chromatography. Application of the enzyme on tea leaves was checked for quality improvement by solvent extraction method. Results and Conclusion: The polygalacturonase of Aspergillus fumigatus was purified to 19.18 fold as a single step purification was achieved by DEAE-cellulose anion-exchange chromatography. SDS-PAGE analysis revealed that the purified polygalacturonase was a heterodimer of 46 kDa and 58 kDa subunits. The corresponding Km and Vmax values for the purified polygalacturonase were achieved as 0.19 mg/ml and 17.85 ?molml-1min-1 respectively. There is significant (p < 0.001) increase in theaflavin, thearubigin, highly polymerized substances and total liquor color contents of tea when oxidized tea leaves were sprayed with crude and purified polygalacturonase (5Uml-1) thereby, indicating the role of these enzymes in the improvement of tea quality. Conflict of interest: The authors declare that there is no conflict of interest.

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