Primary, Secondary Metabolites and Antioxidant Activity of Castanopsis Argantea, Artocarpus heterophyllus, and Aglaia tomentosa Fruit as Food for the Tapanuli Orangutan (Pongo tapanuliensis) in the Batang Toru Forest, North Sumatra

Food plays a crucial role in providing optimal nutrition to maintain the health of the Tapanuli orangutan (Pongo tapanuliensis). The diet of the Tapanuli orangutan consists of Castanopsis argantea, Artocarpus heterophyllus, and Aglaia tomentosa which contain important components such as phytochemicals and proximates with antioxidant effects. The composition of these metabolites correlates with the health of the Tapanuli orangutan. This research aims to identify primary and secondary metabolites, such as proximates and amino acids, as well as bioactive compounds with antioxidant activity. Castanopsis argantea, Artocarpus heterophyllus, and Aglaia tomentosa fruits were tested for proximate, amino acid, phytochemical, and total flavonoid content. Liquid Chromatography-Mass Spectrometry/Mass Spectrometry (LC-MS/MS) and the Ferric Reducing Antioxidant Potential (FRAP) method were employed to determine antioxidant activity. Proximate content and amino acid content tests showed that Castanopsis argantea had significantly higher levels (P<0.05) of carbohydrates (84.09%), fat (3.07%), energy from fat (27.69 Kcal/100 g), total energy (386.34 Kcal/100g), and amino acids such as L-Histidine (1721.09ppm), L-Isoleucine (1329.17ppm), and L-Lysine (1484.99ppm). Phytochemical screening is most notable in Aglaia tomentosa, showing positive results for alkaloids, flavonoids, saponins, tannins, phenolics, and quinolines. Aglaia tomentosa contains the highest total flavonoid content (23.27 ± 3.46 mg QE/g). The bioactive compounds found in Castanopsis argantea consist of caffeine and flazin. Artocarpus heterophyllus comprises Synephrine and Schinifoline while Aglaia tomentosa consists of Artoindonesianin B and 2,5-Di-tert-butylhydroquinone. The highest antioxidant was found in Artocarpus heterophyllus (4.85 ± 1.13µg/mL). The results of the research show that the three foods of the Tapanuli orangutan have excellent potential as sources of nutrition and natural antioxidants. Understanding the relationship between diet and health, including stress from habitat changes, immune system suppression, and environmental factors affecting the Tapanuli orangutan, can lead to more effective and sustainable conservation strategies through the cultivation of these plants.