A review on konjac glucomannan and hydrolysed konjac glucomannan

Konjac glucomannan (KGM) and hydrolysed konjac glucomannan (HKGM) are natural polysaccharides that have many applications in the food and non-food fields (chemical and health industries) due to their non-hazardous, non-toxic, biocompatible properties and good solubility. KGM was produced from pulverising chips, followed by air classification of solid particles to separate them from impurities or ethanol precipitation. Production of KGM from the genus Amorphophallus by the extraction and purification methods was critically reviewed. Characteristics of the physicochemical properties of KGM were outlined, and the preparation of HKGM was also discussed. The potential of KGM and HKGM to provide health benefits, such as being prebiotics or anti-inflammatory and antitumour agents, were considered. A brief discussion on the safe usage of KGM and HKGM is included. Meanwhile, HKGM was prepared by physical-acid treatments or enzymic degradation. Clinical studies have demonstrated that supplementing the diet with KGM or HKGM significantly lowers plasma glucose and reduces inflammation in rat models. Tumour was reduced when KGM was added to the test meals.