Total Phenolic Content and Antioxidant Activity of Morinda tinctoria Leaves

The antioxidant activity and total phenolic content of Morinda tinctoria leaves was evaluated. The successively extracted leaves of Morinda tinctoria using various solvents was analyzed for their total phenolic content. The extracts were subjected to column chromatography for the isolation of bioactive molecules. In vitro antioxidant activity was evaluated by employing different assays, including 2,2-diphenyl-1-picrylhydrazyl, nitric oxide scavenging assay and phosphomolybdenum reducing power assay. The 2,2-diphenyl-1-picrylhydrazyl radical scavenging efficacy of hexane extract is significant at higher concentration (500 μg/ml-91.2±0.05%) and the efficacy at lower concentration is more significant for ethyl acetate extract (100 μg/ml - 65.1±0.05%). The total phenolic content was highest in methanol extract (5.30±0.011 μg/mg). Cynarin, a hydroxy cinnamic acid was isolated from chloroform extract; oleuropein, a polyphenolic iridoid was isolated from methanol extract. The results obtained suggeted that Morinda tinctoria leaf extracts possessed antioxidant properties and might offer protection from free radicals. Two compounds, cynarin and oleuropein were reported for the first time from Morinda tinctoria leaves.

5-Lipoxygenase and cyclooxygenase inhibitory dammarane triterpenoid 1 from Borassus flabellifer seed coat inhibits tumor necrosis factor-α secretion in LPSInduced THP-1 human monocytes and induces apoptosis in MIA PaCa-2 pancreatic cancer cells

Phospholipase A2 (PLA2), Cyclooxygenase (COX) and 5-Lipoxygenase (5-LOX) are arachidonic acid metabolizing enzymes and their inhibitors have been developed as therapeutic molecules for cancer and inflammation related disorders. In the present study, PLA2, COX 1&2 and 5-LOX inhibitory studies of Borassus flabellifer seed coat extract were carried out and substantial 5-LOX inhibitory activity was found. Dammarane triterpenoid 1 (Dammara-20,23-diene-3,25-diol) was isolated according to 5-LOX activity guided isolation, and screened for COX (1 & 2) inhibitory activities. Dammarane triterpenoid 1 inhibited carrageenan-induced rat paw edema and TNF-α secretion levels in lipopolysaccharide (LPS)-induced THP-1 human monocytes. Anticancer activity studies demonstrated the antiproliferative effect of dammarane triterpenoid 1 on various cancer cell lines including MIA PaCa-2 pancreatic, DU145 prostate, HL-60 leukemia and Caco-2 colon cancers. Dammarane triterpenoid 1 showed good antiproliferative activity on MIA PaCa-2 pancreatic cancer cell line with IC50 of 12.36±0.33 µM, among other tested cell lines. Apoptosis inducing activity of dammarane triterpenoid 1 was confirmed based on increased sub-G0 phase cell population in cell cycle analysis, loss of mitochondrian membrane potential, elevated levels of cytochrome c, nuclear morphological changes and DNA fragmentation in MIA PaCa-2 pancreatic cancer cells. Therefore, dammarane triterpenoid skeleton may raise the hope of developing novel anti-inflammatory and anticancer drugs in the future.