Synthesis, Characterization and Antimicrobial Activity of Chitosan Vanillin Schiff Base

INTRODUCTION One of the largely used families of organic compounds includes ‘Schiff bases’ or imines. They are used as artificial intermediates and also in coordination chemistry [1]. The compounds with the structure of–C=N-(azomethine group) are known as Schiff bases, which are usually synthesized from the condensation of primary amines and active carbonyl groups [2]. Among the substituted biopolymers, particularly noteworthy are the Schiff bases obtained by the reactions of the free amino groups of chitosan with an active carbonyl compound such as aldehyde or ketone [3]. The extension of Schiff base formation is called degree of substitution (DS). It is the number of free amino groups in relation to the Schiff bases on the substituted biopolymeric matrix. This is an important parameter that plays an important role in the application of Schiff bases. From literature survey it has been established that the chloro, nitro, methyl substituted benzaldehyde have medicinal, biological, pharmacological, industries and agricultural values but very less work has been carried out on the derivatives of substituted benzaldehyde groups [2]. Vanillin (chemical name:3-methoxy-4-hydroxy benzaldehyde) is one of the most widely used flavorings in food, pharmaceuticals and daily chemicals [4].Natural vanillin is produced by bioconversion or physical methods from natural materials. The cost of the extraction of pure natural vanillin from pods is highe than the cost for the production of synthetic vanillin. Currently, approximately 50%of the worldwide production of synthetic vanillin is used as an intermediate for the production of herbicides, antifoaming agents or drugs [5,6]. Because of its antioxidant and antimicrobial properties ,vanillin could be used as food preservative [7,8].