Standardization of Garcinia mangostana fruit rind extract

The extract of Garcinia mangostana fruit rind has been popularly used in food supplement and herbal cosmetics. Therefore, it is necessary to establish the specification for quality assessment of the extract. The 95% ethanolic extracts of G. mangostana fruit rind collected from 15 different locations in Thailand were prepared by Soxhlet extraction. The content of α-mangostin, which is a major component, was analysed by HPLC method [1]. Loss on drying, solubility, TLC fingerprint and chemical identification of each extract were determined. The heavy metal, pesticide and microbial contamination were also determined. The extract ratio (crude drug:extract) was 3–5:1, while the contents of α-mangostin in dried powder and in the extract were in the range of 1.71–2.70 and 5.79–11.12, respectively. The extracts were yellow-brown powder with characteristic odor, while loss on drying was in the range of 4.52–9.27%w/w. All extracts were soluble in ethanol, propylene glycol and polyethylene glycol but insoluble in water. The extracts gave a positive result with Shinoda's test, gelatin salt test and promote green-color with ferric chloride solution. TLC-fingerprints of all extracts showed similar pattern with band of a major α-mangostin. The extract contained arsenic <0.05 ppm, lead <0.25 ppm, cadmium <0.02 ppm and pesticide contamination was not detected. The extracts contained total aerobic bacteria count and total yeast and mold count not more than 5×10⁵ and 5×10³ cfu/gram, respectively and no pathogenic bacteria was found. This information will be useful for quality assessment of G. mangostana fruit rind extract used as raw material in pharmaceutical and herbal cosmetic products.

Acknowledgements: This study is a part of Ph.D. thesis of Mahidol University and was granted by the University Research Fund.

Reference: [1] Pothitirat, W. and Gritsanapan, W. (2007) Planta Med. 73:892–893.