Physicochemical Properties, Antioxidant and Anti-proliferative Capacities of Dried Leaf and Its Extract from Xao tam phan (Paramignya trimera )

Xao tam phan (P. trimera) has been used for the treatment of cancer and cancer-like aliments. Among different parts of P. trimera plant, leaf is considered as a residual part after harvesting of the root. This study aimed to determine the physiochemical properties, antioxidant and anti-proliferative capacities of P. trimera leaf (PTL) using microwave drying for the preparation of dry sample; methanol and microwave-assisted extraction for the preparation of crude extract; and freeze drying for the preparation of powdered extract. The results showed that total phenolic, total flavonoid, proanthocyanidin and saponin contents of PTL prepared by microwave drying at 450 W were 25.4 mg gallic acid equivalents (GAE), 86.3 mg rutin equivalents (RE), 5.6 mg catechin equivalents (CE), and 702.1 mg escin equivalents (EE) per g dried sample, respectively. Gallic acid, protocatechuic acid, ellagic acid, rutin, and quercetin were identified in the PTL methanolic extract. Dried PTL displayed potent antioxidant activity, while the powdered PTL extract exhibited great anti-proliferative capacity on various cancer cell lines including MiaPaCa-2 (pancreas), HT29 (colon), A2780 (ovarian), H460 (lung), A431 (skin), Du145 (prostate), BE2-C (neuroblastoma), MCF-7 (breast), MCF-10A (normal breast), and U87, SJ-G2 and SMA (glioblastoma). Anti-proliferative capacity on pancreatic cancer cells (MiaCaPa2, BxPc3, and CFPAC1) of PTL extract (200 μg/mL) was significantly higher (P < 0.05) than those of ostruthin (20 μg/mL) and gemcitabine (50 nM), and to be comparable to the powdered P. trimera root extract and a saponin-enriched extract from quillajia bark (a commercial product). The findings from this study allow us to conclude that the PTL is a rich source of phytochemicals that possess promising antioxidant and anti-proliferative activities, therefore it shows potential as lead compounds for application in the nutraceutical, medicinal and pharmaceutical industries. This article is protected by copyright. All rights reserved.