Nutritional and bioactive compound analysis of mangosteen fruit in hill and flat land plantations, during both the season and off-season, in provinces along the Gulf of Thailand and the Andaman Sea

This study examined the nutritional, physicochemical, and bioactive compounds in mangosteen grown in southern Thailand from 2022 to 2024, encompassing hilly areas (Nakhon Si Thammarat range, Tenasserim range) and flat lands during both the fruit season and off-season. The influence of coastal regions (Gulf of Thailand and Andaman coast) on mangosteen nutrition was explored. The impact of high-level plantation and harvesting (during the fruit season) on mangosteen size and levels of bioactive compounds with high antioxidant capacity in mangosteen flesh was found to be greater than that of flat plantations (during the off-season). Mangosteens grown in flatlands during the fruit season exhibited brighter flesh color and faster ripening compared to those grown in hilly areas. Mangosteens from these results contained carbohydrates ranging from 10.3% to 16.9%. Mangosteens cultivated along the Andaman coast exhibited elevated levels of minerals (K 349 mg/100 g, Na 7.76 mg/100 g, and Mn 1.63 mg/100 g) and vitamins, especially B₂ (0.10 mg/kg), B₆ (0.20 mg/kg), B₁₂ (0.03 mg/kg), and vitamin C (9.25 mg/kg). Conversely, the highest total phenolic content, flavonoids, and antioxidant activity were observed in hilly areas during the fruit season along the Gulf of Thailand (55 mg GAE/100 g, 32 mg QE/100 g, and ABTS values of 88%, respectively). However, mangosteens from hilly areas ripened faster than those from flatlands due to higher total soluble solids and lower fruit firmness. These findings provide valuable insights into the effects of the environment and location, enhancing understanding for year-round mangosteen plantation preparation.