STRUCTURE ELUCIDATION AND THERAPEUTIC APPLICATIONS OF ENDOPHYTIC FUNGI DERIVED BIOACTIVE COMPOUNDS OBTAINED FROM XIMENIA AMERICANA WESTERN GHATS OF KARNATAKA INDIAAbstract
The objective of the present investigation was the bioprospection of pharmaceutically vital bioactive compounds from endophytic Thielaviopsis basicola with antagonistic and antioxidant activity isolated from Ximenia americana, Western Ghats of Karnataka, India. The fresh and healthy leaves and roots of Ximenia americana were collected from the forests of Western Ghats of Karnataka, India and submerged for the enumeration and Purification of fungal endophytes by using different media. Isolated fungal endophytes were processed for the bioprospection of pharmaceutically vital bioactive compounds by referring to standard protocols. At a glance, endophyte derived bioactive compounds were used in-vitro antagonistic and antioxidant activity. A total of 32 pure isolates were obtained, 8 morphologically distinct fungal endophytes were identified from 200 explants of X. americana. Endophytic Thielaviopsis basicola was a core candidate identified and cultivated in submerged fermentation in potato dextrose broth under the controlled condition at 25 ℃ ± 2℃ for 15 days in incubator shaker. From this fermented medium, 3.30 g of aqueous crude extract per 100 ml of potato dextrose broth was obtained by the solvent-solvent extraction method. The qualitative phytochemical analysis showed a broad spectrum of bioactive compounds such as alkaloids, terpenoids, flavonoids, phenols, tannins, and glycosides. It was found that the aqueous crude extract contains 23.0090 ± 0.04129 mg of phenol and 53.47 ± 0.88059 mg of flavonoids content. From these crude extract TBXA1 and TBXA2, two fractions were purified by column chromatography and spotted potent bioactive compounds on thin-layer chromatography. The FTIR data of TBXA1 and TBXA2 showed different functional groups such as alcohol, phenols, alkanes, alkenes, aromatic, alkyl halides, amines, ether, and nitrile. The TBXA1 exhibited prominent antagonistic activity and MIC against Staphylococcus aureus (24 mm with 100 µg/mL) and Candida albicans (22 mm with 75 µg/mL) while TBXA2 exhibited against Salmonella typhi (22 mm with 75 µg/mL) and Aspergillus fumigatus (18 mm with 75 µg/mL). The TBXA1 showed potent antioxidant activity (86.24 ± 0.35) with 5.26 µg/mL of IC50 value as compared with TBXA2. This is the first innovative report of endophytic Thielaviopsis basicola for their phytochemicals detection and prominent in-vitro activities.
R. S. Mane and A. B. Vedamurthy *
Department of Biotechnology and Microbiology, Karnatak University, Dharwad, Karnataka, India.
24 April 2019
08 November 2019
24 December 2019
01 January 2020