Anti-protein glycation and free-radical scavenging properties of Sri Lankan antidiabetic medicinal plant Salacia reticulata l. (Kothala Himbutu)

BACKGROUND: Decoctions of the root and stem of the medicinal plant Salacia reticulata is an indigenous remedy for diabetics and its complications in Sri Lanka. In diabetics, the formation of advanced glycation end products (AGEs) leads to many pathologies. Nevertheless, the anti-protein-glycation property of this plant is poorly documented. This study reports the anti-protein-glycation and radical scavenging potential of various plant parts of S. reticulata. METHODS: Hot water extracts (2g dried powder/50 ml) of root, stem, leaf, twigs, and fruits at various concentrations (15.6 to 500.0 µg/ml) were subjected to anti-glycation and glycation reversing assays in vitro. 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay was used for free radical scavenging property. RESULTS: Various plant parts of S. reticulata showed anti-protein-glycation and free-radical scavenging activities. IC(50) for the anti-glycation activity of root, stem, leaf, twigs, and fruit extracts were 11.92 ± 1.14, 35.18 ± 2.79, 113.3 ± 1.91, 149.59 ± 1.06, and 1120.37 ± 229.48 µg/ml respectively. IC(50) of Rutin was 21.88 ± 2.82 µg/ml. EC(50) of the root, stem, twigs, and leaf extracts for glycation reversing was 102.09 ± 6.23, 116.99 ± 5.82, 154.45 ± 5.79, and 278.78 ± 14.19 µg/ml respectively. The EC(50) values for the radical scavenging activity of leaf, stem, and roots were 26.4±4.7, 9.0±1.2, and 9.1±1.3 respectively. Root had significantly (p<0.05) high activity for all the parameters tested. CONCLUSION: Salacia reticulata possess anti-glycation, glycation-reversing, and free radical scavenging activities. Other than root and stem, the leaves and twigs too may be a useful source for anti-diabetic bioactive molecules.