ABSTRACT
The microbial exopolysaccharides are water-soluble polymers secreted by microorganisms during fermentation. The biopolymer gellan gum is a relatively recent addition to the family of microbial polysaccharides that is gaining much importance in food, pharmaceutical and chemical industries due to its novel properties. It is commercially produced by C.P. Kelco in Japan and the USA. This article presents a critical review of the available information on the gum synthesized by Sphingomonas paucimobilis with special emphasis on its fermentative production. Factors affecting the fermentative production of gellan gum and problems associated with mass transfer have been addressed. Classification and trade names of gellan gum has been specified. Characteristics of gellan gum with respect to its structure, physicochemical properties are discussed. An attempt has also been made to review the current and potential applications of gellan gum in food, pharmaceutical and other industries.
Subject(s)
Biopolymers/chemistry , Polysaccharides, Bacterial/chemistry , Sphingomonas/chemistry , Carbon/chemistry , Culture Media/chemistry , Fermentation , Food Industry , Gels/chemistry , Molecular Conformation , Nitrogen/chemistry , Pharmaceutical Preparations/chemistry , Species SpecificityABSTRACT
In recent era various technologies have been made in research and development of controlled release oral drug delivery system to overcome various physiological difficulties such as variation in gastric retention and emptying time. To overcome this drawback and to maximize the oral absorption of various drugs, novel drug delivery systems have been developed. Gastroretentive drug delivery system is facing many challenges which can be overcome by upcoming newly emerging approach i.e. raft forming system. The purpose of writing this review is to focus on recent development of stomach specific floating drug delivery system to circumvent the difficulties associated with formulation design. Various gastroretentive approaches that have been developed till now are also discussed. The present study provides valuable information & highlights advances in this raft forming system. This review attempts to discuss various factors like physiological factors, physicochemical factors and formulation factors to be considered in the development of the raft forming system. Different types of smart polymers used for their formulation have also been summarized. The review focuses on the mechanism, formulation and development of the raft forming system. This review also summarizes the studies to evaluate the performance and application of these systems. The study finally highlights advantages, disadvantages, and marketed preparation of the raft forming system.
