Amylase-assisted extraction alters nutritional and physicochemical properties of polysaccharides and saponins isolated from Ganoderma spp

•A study of canopies and stalks of wild types and cultivated Ganoderma.•Enzymatic extraction yielded a higher saponin content in the canopy of black-type Ganoderma.•Purified Ganoderma extracts had molecular weights ranging from 1400 to 3250 Da.•Emulsification activity of the Ganoderma samples was better than lecithin.•Ganoderma saponins had good thermal stability even at a temperature of 800 °C. This study aimed to evaluate the efficacy of amylase in hydrolyzing complex carbohydrates of different parts of Ganoderma spp. The aqueous extracts of the Ganoderma samples were analyzed for their selected nutritional composition and physicochemical properties. The purified extracts were also structurally characterized. The aqueous canopy extracts of red–purple Ganoderma had a notably higher total sugar and saponin content than their stalks, but not for the black-type Ganoderma. The enzymatic extraction effectively improved the extraction yields, whereas the amounts of sugars and saponins in some extracts were increased after the enzymatic treatment. The results also showed that only those enzyme-treated cultivated black Ganoderma canopy had increased total sugar and total saponin content. The antioxidant activities of all stalk extracts were higher than the canopy extracts. Their emulsifying properties were comparable with lecithin due to their high saponin content. Therefore, these extracts are new natural emulsifiers.