Determination of Zinc(II) Ions Released into Artificial Digestive Juices from Culinary-Medicinal Button Mushroom, Agaricus bisporus (Agaricomycetidae), Biomass of In Vitro Cultures Using an Anodic Stripping Voltammetry Method.

Zinc is one of those microelements that are essential for the proper functioning of the human body and must be supplemented in our food at a daily dose of 15 mg. It is well known that mushrooms accumulate elements; thus, in order to determine the extent of accumulation and the level of zinc released from mushrooms, in vitro cultures of Agaricus bisporus were established. The cultures were run on a modified Oddoux medium (a control culture) as well as on the same medium with the addition of zinc hydroaspartate (100 and 200 mg/L) and zinc sulfate (87.23 and 174.47 mg/L). These compounds were chosen to help estimate which form, organic or inorganic, results in a better assimilation of zinc(II) ions by biomass. As the next step, the level of zinc(II) ions released from the lyophilized biomass of in vitro cultures to the digestive juices, under thermal conditions of the human body (37°C), was determined. For this purpose, artificial digestive juices, imitating the composition of human digestive juices, were used. For determination of zinc(II) ions in the digestive tract, an anodic stripping voltammetry method was employed. The amount of zinc released into artificial saliva over 1 minute varied from 0.15 mg/100 g d.w. in the control culture to 2.35 mg/100 g d.w. in the biomass in the medium to which 200 mg/L zinc hydroaspartate had been added. Values were higher in gastric juice and depended on incubation time (2.66 to 30.63 mg/100 g d.w.). In intestinal juice, the highest value of the released zinc grew to 24.20 mg/100 g d.w. (biomass of A. bisporus in vitro cultures in medium with the addition of 200 mg/L zinc hydroaspartate). Total average amount of zinc released into artificial digestive juices was the highest (56.26 mg/100 g d.w.) from A. bisporus biomass of in vitro cultures in the medium to which 200 mg/L zinc hydroaspartate had been added.