Andrographolide

Andrographis paniculata is an important medicinal plant in Indian and Chinese systems of medicine used for a number of ailments. Andrographolide (AP), a diterpene lactone, has been reported to be responsible for many of the activities. A number of methods are available for the isolation of AP.  However, they are time consuming and not cost effective. We employed five relatively simpler methods for the isolation of AP. The identities and purity of the compounds isolated by these five methods were established by thin layer chromatography (TLC), high performance liquid chromatography (HPLC), melting point, ultraviolet (UV), infrared (FTIR), mass, and nuclear magnetic resonance (1H NMR) spectra. Treatment of the extracts with activated charcoal proved to be quite effective in removing all coloring matter and resulted in isolation of pure AP. Of the five methods, prior maceration with methanol for 16 h followed by refluxing for 1h yielded 0.6%w/w of AP and was found to be quite satisfactory. This method does not need prior extraction of the powder with toluene nor does it require washing of the concentrated extract with toluene.  In this method only methanol (MeOH) was employed. All the spectral data and melting point of andrographolide isolated by this method confirmed its purity. This method is simple as it involves only three steps and has the potential for commercial scale up.

Andrographolide is a diterpene lactone present in aerial parts of Andrographis paniculata especially in the leaves. It was reported to possess a wide variety of bioactivities. In the present research immunomodulatory effects of pure andrographolide have been studied on chicken spleenocytes in vitro. The immunological intervention of andrographolide was assayed using Nitro Blue Tetrazolium dye reduction assay, Inducible Nitric Oxide Synthase assay and Macrophage function test. Cytotoxic effects of andrographolide  on spleenocytes were tested using MTT assay. Andrographolide suppressed Nitro Blue Tetrazolium dye reduction assay response at all experimental concentrations. 45% reduction in immune response was observed when spleenocytes were treated with andrographolide at a concentration of 40µg/ml. The overall Inducible Nitric Oxide Synthase assay response of spleenocytes get decreased with incorporation of andrographolide in media. It was observed that when spleenocytes were mitogenically stimulated in presence of Covcanavalin A and Phytohaemagglutinin ,the suppression of Inducible Nitric Oxide Synthase assay response was observed. Andrographolide was found to enhance the phagocytic ability of spleenocytes upto 10 folds. It was found to be nontoxic at the concentration of 40µg/ml and 96% of spleenocytes remained viable as estimated by Trypan blue dye exclusion method. It was found to have immunosuppressive properties and it can be used to treat inflammatory disorders such as allergies, rheumatoid arthritis etc.