Validation and Vitamin C Testing in Crystal Guava (Psidium guajava L.) With Variations of Origin With the HPLC Method (High Performance Liquid Chromatography)

Crystal guava contains high vitamin C. Vitamin C is contained in different fruits, one of the factors is the altitude of the fruit plant growing areas. This study aims to determine the level of vitamin C in the slurry of crystal guava flesh with variations of origin using the HPLC method. Samples of crystal guava are obtained from the city of Bogor, Malang, and Gunung Kidul. The samples to be analyzed are prepared as a slurry. Qualitative analysis is done by identification using KMnO4 p.a, FeCl3 p.a, AgNO3 p.a as well as comparing the retention time of the sample with vitamin C. Method validation for system suitability, linearity and precision provide results that are eligible according to the applicable regulations. Quantitative analysis using HPLC with C18 stationary phase, water: methanol mobile phase (95: 5) v/v, flow rate of 1 mL/min, and run time of 7.5 minutes. Qualitative analysis by using KMnO4, FeCl3, AgNO3, and retention time (tR) shows positive results of the vitamin C existence. The average levels of vitamin C from Bogor, Malang, and Gunung Kidul, equal to (0.4139 ± 0.004) mg/mL; (0.6746 ± 0.03) mg/mL; and 0.8608 ± 0.002 mg/mL respectively.