HCA-CHITOSAN Hydroxycitric Acid + Chitosan HCA (Hydroxycitric Acid) is extracted from the plant Garcinia Cambogia. The HCA content of the Scitec Nutrition HCA supplement is 60%. Inferior brands may contain significantly less of this active ingredient! HCA can contribute to the control of bodyweight, bodyfat and sense of hunger. Chitosan is derived from chitin, an amino polysaccharide fiber found in the shells of shellfish. Chitosan goes through a process called deacetylation, which refers to the removal of acetyl groups. This process increases its solubility.