Synergistic Roles of Alginates and α-Glucans in Gastric Raft Formulations

Heartburn and gastro-oesophageal reflux disease (GORD, GERD USA) are prevalent among millions of people worldwide. There are many antacid products used for the treatment of GORD, and gastric rafts show better relief than antacids alone; when alginates are used in the formulations, a buoyant gel or raft forms on contact with the gastric acid due to the formation of carbon dioxide from carbonates and bicarbonates within the polysaccharide formulations. For long lasting relief it is obviously desirable to retain the raft in the stomach as long as possible. Both pre-gelatinised starch and dextrin were evaluated for their functionality in alginate based raft formulations, with cognisance to the molecular synergism found in polymeric systems containing both starch and alginate. Previous work on satiety linked to raft formats using the synergism of these polysaccharides (alginates and α-glucans) has indicated that in vivo they produce robust rafts within the stomach. Advantages of pre-gelatinised starch and dextrin include: the ability provide a number of unique molecular interactions; being economically advantageous to incorporate (lower cost than alginates); they are naturally derived; they reduce impact on kelp beds; and they are easily digestible in the human digestive system. The authors report on the in vitro rafting properties of alginate-α-glucan combinations and discuss potential application benefits.