A pilot study of antioxidant potential of endophytic fungi from some Sudanese medicinal plants

Asian Pac J Trop Med. 2015 Sep;8(9):701-4. doi: 10.1016/j.apjtm.2015.07.032. Epub 2015 Jul 29.

Abstract

Objective: To evaluate the total phenolic content and total antioxidant capacity of ethyl acetate extracts of 21 endophytic fungi isolated from five Sudanese medicinal plants: Calotropis procera, Catharanthus roseus, Euphorbia prostrate, Vernonia amygdalina and Trigonella foenum-graecum.

Methods: Crude extracts of endophytic fungi and their host plants were tested by classical Folin-Ciocalteu colorimetric method to determine the total phenolic content, also total antioxidant capacity was estimated using 1,1-diphenyl-2-picrylhydrazyl free radical scavenging in vitro method.

Results: Among the endophytes, endophytic fungus Aspergillus sp. from Trigonella foenum-graecum seeds demonstrated the highest both total phenolic content in term of gallic acid equivalent [(89.9 ± 7.1) mg GAE/g] and antioxidant activity for 1,1-diphenyl-2-picrylhydrazyl radical scavenging assay [IC50: (18.0 ± 0.1) μg/mL]. A high positive linear correlation (R(2) = 0.999 1) was found between total antioxidant capacity and total phenolic content of endophytic fungi isolated from Vernonia amygdalina.

Conclusions: The present study revealed that some endophytic fungi from the five Sudanese medicinal plants could be a potential source of novel natural antioxidant compounds.

Keywords: Antioxidant activity; Endophytic fungi; Sudanese medicinal plants; Total phenolic content.