Typhoid fever is more prevalent in developing countries due to poor sanitation and inappropriate use of antibiotics leading to the development of drug resistance in the bacteria. S. typhi has Type I 3 dehydroquinate dehydratase, an enzyme involved in the Shikimate pathway, which converts 3-dehydroquinate to 3-dehydroshikimate. The inhibition of this enzyme will not allow the bacteria to grow. Hence in the present study an attempt has been done to determine the inhibitor activity of certain phytochemicals and their derivatives from Azadirachta indica docking studies. The 3D structure of the enzyme was downloaded from the RCSB database. The structures of hydroxy pivalic acid [pubchem id 78548], (acetyloxy) acetic acid [pubchem id 83766], germanicol [pubchem id 122857], and phytol [pubchem id 5280435] of Azadirachta indica were obtained from pubchem database. Their derivatives in 2D format were generated with the help of software ACD chemsketch. The docking of ligands was performed using AutoDock vina software using PyRx GUI. The present study concludes that the derivatives of the various phytochemicals of Azadirachta indica can be exploited to identify a potential drug candidate in the treatment of enteric fever.

Keywords: Salmonella typhi, Azadirachta indica, Molecular docking, ADMET properties.

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Dr I. Kannan

Associate Professor of Microbiology, Tagore Medical College and Hospital, Rathinamangalam, Chennai – 600127