07-08-2013, 01:09 PM
In vitro assessment of the DPPH free radical scavenging activity of Digitalis lanata and its fungal endophytes
ABSTRACT
Endophytes being the symbiotic microorganisms within the living tissues of host plants have proved to be useful in various aspects of life. These being the chemical synthesizers inside plants provide useful bioactive secondary metabolites having tremendous applications in pharmaceuticals, industries and agriculture. In the present study, endophytes were isolated from the symptomless leaves of Digitalis lanata (wooly fox glove). A total of sixteen fungal endophytes were isolated. Morphological identification of only three cultures was done due of lack of sporulation and other morphological features from the rest of fungal cultures. Extraction of secondary metabolites from the plant material and three selected fungal cultures was done by conventional method using Soxhlet. These extracts were run on preparative TLC plates to check the presence of same compounds as produced by the plant itself. Then the extracts were checked for their antioxidant potential. Free radical scavenging activity of these extracts was determined in vitro by DPPH (1,1-diphenyl-2-picrylhydrazyl) assay. All the three fungal extracts along with the plant extract showed significant antioxidant activities. DPPH radical scavenging activity shown by the plant and fungal extracts was concentration dependent. With the increase in concentration, the radical scavenging activity increased in all the extracts.