Isolation and HPTLC Densitometric Analysis of Rutin in the Broth Extract of Endophytic Aspergilluis flavus from Aegle marmelos

Abstract

A dominant bioflavonoid-rutin was isolated from the fermentation broth of endophytic Aspergillus flavus obtained from Aegle marmelos. A simple, rapid and reliable High-Performance Thin-Layer Chromatographic (HPTLC) method was developed for the analysis of rutin. HPTLC was carried out for qualitative determination of flavonoids in the fermentation broth using silica gel 60 F254 20×20cm thickly plated preparative chromatography plates as a stationary phase and ethyl acetate, glacial acetic acid and formic acid (5:0.5:1, v/v) as mobile phase. The plates were scanned densitometrically between 200 and 700 nm. The fermentation extract of the endophytic Aspergillus flavus produced metabolite and showed a compact and well resolved blue band with the same Rf (0.32±0.02) to that of authentic rutin. The bioactive metabolite produced by endophytic fungi is generally less than their host plant. However, in this study, the flavonoids were easily detected with HPTLC indicating more production of the metabolite. The present study demonstrates a new method to produce, isolate and analyze flavonoids by fungal fermentation, which could overcome the extensive use of the host plant.