Polyphenolic compounds with anti-AGEs activity from three Clusiaceae plants

Aim: This study focused on finding molecules with inhibitory effects on Advanced Glycation End-products (AGEs) formation from Tanzanian some Clusiaceae plant species Study Design: Field study and Laboratory experimental tests. Place and Duration of Study: Institute of Traditional Medicine, Muhimbili University of Health and Allied Sciences, P.O. Box 65001, Dar es Salaam, Tanzania and PRES LUNAM, Université d’Angers, EA 921 SONAS, 16 Bd Daviers, 49045 Angers, France, between June 2011 and July 2013. Methodology: Three Clusiaceae plant species (Garcinia semseii, G. volkensii and Allanblackia ulugurensis) were collected and dried in the field with the assistance of a botanist. Extraction and concentration of plant samples to obtain crude extracts were done in the laboratory following standard procedures. The isolation of the phenolic compounds was carried out by using normal phase column chromatography as well as High-performance liquid chromatography (HPLC). The isolated compounds were tested for anti-AGE activity using the in vitro automated assay. Results: Two polyphenolic compounds exhibiting phloroglucinol moieties [e.g. polyprenylated benzophenones, such as guttiferone F, 2 (18 mg)] or biflavonoids [such as morellof lavone, 1 (22 mg)] were isolated and identified from A. ulugurensis and G. volkensis respectively. The results further indicated that compound 1 is an excellent inhibitor of AGE formation exhibiting an IC 50 values of 78 and 64 μM at wavelength of 370/440 (vesperlysines-like AGEs) and 335/385 (pentosidine-like AGEs) respectively. Conclusion: Plants belonging to the Clusiaceae family commonly used in Tanzanian traditional medicine need to be considered as a potential source of molecules exhibiting pharmacological activities such as anti-AGE activity. Morelloflavone (1) and other biflavonoids prove to be very good anti-AGE compounds using our automated screening assay. Hence, our automated in vitro assay allows a fast, effective and quite inexpensive screening of natural compounds and can therefore be applied to high throughput screening project