Study Of α-Mangostin Compound And Antidiabetic Assay From Fruit Hull Of Garcinia Mangostana Linn. Devyana Dyah Wulandari, 1* Taslim Ersam a Postgraduate Program in Chemistry Departement, Faculty of Mathematic and Science, Institut Teknologi Sepuluh Nopember b Penelitian Aktivitas Kimiawi Tumbuhan (PAKTI) Group, Chemistry Departement, Faculty of Mathematic and Science, Institut Teknologi Sepuluh Nopember *Corresponding author, email: paktichem@gmail.com Abstract. Garcinia mangostana Linn. is known as ‘‘the queen of fruits” because it is one of the best tasting tropical fruits. The mangostin-fruit has been used as a m edicinal agent, such as antioxidant, antiproliferasi, antibacterial agent, anticancer, anti HIV, decreases the human low density lipoproteins (LDL) oxidation, induced apoptosis in human leukemia cell lines, anti hypertensive, anti malaria, and many others. Based on an information, mangostin has an antidiabetic bioactivity, but there are not any data that support this information. Therefore, this research is required to obtained α-mangostin compounds, and antidiabetic bioactivity assay contained in fruit hull G. mangostana. Antidiabetic activity was investigated in normal and diabetic rat. Animals were treated intraperitoneally with a single dose of 120 mg/kg alloxan to induce diabetes. This resulted in significant increase in blood glucose level. The diabetic and normal rat were both randomly divided into 6 group. Group A (negative control) received distilled water ad libitum. Group B (positive control) were treated intraperitoneally with single dose of 120 mg/kg alloxan. Group C, D, and E were treated intraperitoneally with single dose of 10, 30, and 50 mg/kg α-mangostin. Group F received 10 mg/kg glibenclamide for the same period. Blood glucose levels and changes in body weight were evaluated in normal rats. The diabetic groups treated with α-mangostin were compared with standard glibenclamide. The findings of the study support the antidiabetic claims of α-mangostin. Keywords: Garcinia mangostana Linn., xanthone, mangostin, antidiabetic. INTRODUCTION The mangosteen-fruit is dark purple or reddish, with white, soft and juicy edible pulp with a slightly acid and sweet flavor and a pleasant aroma. Mangosteen is known as ‘‘the queen of fruits” because it is one of the best tasting tropical fruits. The pericarp of mangosteen-fruit has been used as a medicinal agent by Southeast Asians for centuries in the treatment of skin infections and wounds, amoebic dysentery, etc. In Ayurvedic medicine the pericarp of mangosteen-fruit has wide use against inflammation and diarrhea, and cholera and dysentery (Chaverry, 2008). It has been a lot of data from research results showing that G. mangostana has a wide range of bioactivity that can be used in the health and medicine related, among others, as antiproliferasi (Moongkarndi P, 2004), anti-bacterial (Suksamrarn S, 2003), anticancer (Huang, 2002), anti-HIV (Vlietinck, 1998) , inhibit oxidation of Low Density Lipoprotein (LDL) (Williams, 1995), induce apoptosis (Sato, 2004) anti-hypertensive (Wang, 2002), anti-malarial (ignatushchenko, 1997) and there are many others. In addition, from a source of information indicates that the G. mangostana has activity as an antidiabetic, but there is still no research data to support this information (25 Mangostin Natural Miracles). On the other hand, the source of information about the condition of society in Indonesia showed that in 2000 an estimated 150 million people worldwide have diabetes mellitus. This amount is expected to rise to double in 2005, and mostly, the increase will occur in developing countries such as Indonesia. Population of diabetics in Indonesia is estimated to range between 1.5 to 2.5% except in Manado 6%. With a population of around 200 million inhabitants, means approximately 3-5 million people in Indonesia suffer from diabetes. Recorded in 1995, the number of diabetics in Indonesia reached 5 million people. In 2005 expected to reach 12 million diabetic patients. Although Diabetes Mellitus (DM) is a chronic disease that does not cause death directly, but can be fatal if not managed appropriately. The management of DM requires a multidisciplinary treatment that includes non-drug therapy and drug therapy (Depkes RI, 2005). One part of the culture of Indonesia relating to the utilization of natural wealth, that is for