Comparative analysis of Extraction and Determination of Inulin by Spectrophotometric and TLC methods from Indian plant sources

Abstract

Inulin a versatile multifunctional polyfructan, has been employed in food industry as a low-calorie sugar and fat replacer, as a dietary fiber, as a prebiotic agent in pharmaceutical, in food formulations and in drug targeting and nanotechnology. The growing need and application of plant-based natural products like inulin in food, health and pharma industry necessitates the need for a routine and valid method to extract and quantify inulin present in most of the plant materials of Indian origin. Aim of this study was to extract inulin using ethanol and water as extracting solvents and compare the inulin content extracted from various plant sources using two spectrophotometric methods. The result indicated that inulin extracted using both the solvents when determined spectrophotometrically showed chicory, dahlia and onion as good sources while banana, taro and barley with low inulin. Thin layer chromatogram of inulin extracts showed the presence of fructose, glucose, sucrose and inulin and also other saccharides. The analysis of inulin content can be made efficient with suitable preparation or extraction method combined with an appropriate bioanalytical method to screen different sources. For routine study, either ethanol or water can be used to extract inulin along with a rapid and sensitive spectrophotometric method like Roe’s Resorcinol method can be implemented.