Antioxidative and L-asparaginase potentials of fungal endophytes from Rauvolfia densiflora (Apocynaceae), an ethnomedicinal species of the Western Ghats

摘要

This study focuses on the isolation and molecular characterisation of fungal endophytes from an ethnomedicinal plant, Rauvolfia densiflora (Apocynaceae), and an evaluation of antioxidative and L-asparaginase potentials. Fungal endophytes were isolatedfrom leaf and stem parts of R. densiflora collected from the site of Talacauvery, Western Ghats, India. The highest colonisation frequency was found in leaves (95.5%), followed by stem parts (63.5%).A total of 19 fungal morphotypes belonging to 11 genera were identified by analysing the ITS sequences of the endophytes. The strains were screened for asparaginase production by qualitative plate assay and quantification by Nesslerisation. Maximum activity was recorded in the PeniciUium chrysogenum culture (3.77 IU/ml). Submerged fermentation and ethyl acetate extraction were carried out to obtain secondary metabolites for the evaluation of total phenolic content (TPC) and antioxidative potentials. TheTPC of fungal extracts ranged from 12.37 to 89.29 mg GAE/g dry extract and the IC_(50) value of scavenging activity from 26.64 to 547.23 ug/ml. The P. chrysogenum strain (MH392736) was found to have the potentially highest total phenolic content and a high antioxidant capacity. This is the first report on the characterisation of fungal endophytes from R. densiflora and their antioxidative and L-asparaginase potentials.