Evaluation of endophytic fungal fractions of Andrographis paniculata (Burm.f.) Wall. Nees leaves for in vitro free radical scavenging and hepatoprotective activity

Abstract

Fungal endophytes are the microbes residing in internal tissues of the plant forming symbiotic, mutualistic, communalistic and trophobiotic relationship. Endophytes from medicinal plants are considered as essential source of secondary metabolites accompanied by interesting biological/pharmacological activities. In this study, an effort was made to isolate, characterize endophytic fungi from leaves of Andrographis paniculata and to screen the fungal fractions for in-vitro antioxidant and hepatoprotective activity. Two fungal endophytes (APLF-1 and APLF-2) from Andrographis paniculata were isolated and fermented to get chloroform (A1C, A2C), ethyl acetate (A1EA, A2EA) and n butanol (A1nB, A2nB) extracts. All the endophytic fractions of APLF-1 and APLF-2 were assayed for free radical scavenging properties against 2, 2-diphenyl-1-picrylhydrazyl (DPPH), hydroxyl radical and reducing power. Fractions of APLF-2 showed good scavenging activity compared to APLF-1 extracts. Further, A2EA and A2nB were evaluated for hepatoprotective activity against CCl4 induced hepatotoxicity. A2EA (50 mg/kg &100 mg/kg) and A2nB (50 mg/kg &100 mg/kg) reversed the elevated biochemical parameters with respect to CCl4 treated group (p<0.001). The LPO, SOD and CAT levels were also restored by A2EA and A2nB (100 mg/kg p.o). APLF-1 and APLF-2 were studied for rDNA sequencing by PCR technique. The endophytic fungi, APLF-1 and APLF-2 were identified as Diaporthe sp. A25 and Preussia sp. PPV3.6 respectively based on their morphology and molecular characterization. The presence of polyvalent secondary metabolites in A2EA and A2nB were confirmed by HPTLC analysis.