Cytotoxicity of Enterolobium timbouva Plant Extract and Its Isolated Pure Compounds.

Aims: The present study aimed to evaluate the cytotoxic activities of the aqueous alcohol extract of Enterolobium timbouva leaves as well as its isolated pure compounds. Place and Duration of Study: Department of Pharmacognosy, Faculty of pharmacy, Ain Shams University, between March 2010 and May 2012. Methodology: In vitro Cytotoxic study was conducted for the aqueous methanol extract and the isolated pure single compounds to determine the IC50 by sulphorhodamine B (SRB) assay. Results: Phytochemical investigation of the extract resulted in the isolation and structural determination of ten phenolic compounds isolated for the first time from entitled genus viz; 3,4-Dihydroxy-Cinnamic acid (Caffeic acid) (1); Quercetin-3-O-β-D-glucopyranoside (Isoquercitrin) (2); Quercetin-3-O-β-D-galacto-pyranoside (Hyperin) (3); Kaempferol-3-O- β-D–glucopyranoside (Astragalin) (4); Hesperetin-7-O-rutinoside (Hesperidin) (5); Quercetin 3-O-rutinoside (Rutin) (6); Quercetin (7); Kaempferol (8); 7-methoxycoumarin (Herniarin) (9); and Chrysin (10). The aqueous alcohol extract exhibited potent cytotoxic activity against diffferent cancer cell lines with IC50 values of 2.67 μg/mL against MCF-7 cell line, 3.89 μg/ml against HCT116 cells, 4 μg/mL against HEp2 cells, 4.5 μg/mL against HeLa cells, 1.7 μg/mL against PC-3 cells, and 5.7 μg/mL against Huh-7 cells. In vitro cytotoxic assay of the isolated pure compounds against Huh-7 cell Line showed that compounds 1, 9 and 10 are the only tested compounds exhibiting potent cytotoxic activity with IC50 of 3 μg/mL, 0.76 μg/mL, and 18.51 μg/mL respectively. The rest of tested compounds exhibited IC50 exceeding 1000 μg/mL which reflects their safety. Conclusion: The current study indicated that the phenolic compounds isolated from Enterolobium timbouva leaves are promising molecules with potentially useful cytotoxic activity profiles. This confirms that this terrestrial plant has great value as a source of lead compounds with pharmaceutical applications.

Rhoifolin; A Potent Antiproliferative Effect on Cancer Cell Lines.

Aims: To investigate the cytotoxic activity of rhoifolin against different cancer cell lines. Study Design: Isolation, identification and cytotoxic activity evaluation. Place and Duration of Study: Faculty of Pharmacy, Ain Shams University and Al-Azhar University, between October, 2010 and January, 2011. Methodology: Rhoifolin, Apigenin 7-O-β neohesperidoside was isolated in a copious amount from the leaves of Chorisia crispiflora (Bombaceae). Its identity was unambiguously confirmed via different spectroscopic methods (UV, 1HNMR, 13CNMR and HMBC) and viability assay test was used to evaluate its cytotoxic activity. Results: It exhibited potent anticancer activities, nearly similar to that of vinblastine, when evaluated against human epidermoid larynex (Hep 2) and human cervical (HeLa) carcinoma cell lines. Promising activities were also obtained against hepatocellular (Hep G2), colon (HCT-116) and fetal human lung fibroblast (MRC-5) carcinoma cell lines. A unique effect of rhoifolin was in having no cytotoxic activity against healthy normal cells (Vero cells) which indicates a high selectivity of this compound. Conclusion: The findings of this study showed that rhoifolin could be used as an ideal anticancer agent. It discriminates between cancerous and non cancerous cell as it kills only the former one. So the side effects which may appear during chemotherapy could be overcome.

Anti-inflammatory Effect of Apigenin-7-neohesperidoside (Rhoifolin) in Carrageenin-Induced Rat Oedema Model.

Flavonoids are normal constituents of the human diet and are known for a variety of biological activities. They have been reported to bring benefits in lowering inflammation and oxidative stress. The present investigation was performed first, to evaluate the anti-inflammatory activity of rhoifolin and second, to search for the possible contributing mechanisms for this hypothesized effect. Rhoifolin caused a time and reverse dose dependent reduction of carrageenin-induced rat paw oedema. Following 4 hr of treatment, rhoifolin at doses 2.5, 25 & 250 mg/kg caused a significant inhibition of rat paw edema volume by 14, 25 & 45 % respectively in comparison to the control group (74%). In addition to significantly abrogating prostaglandin E2 level, increasing doses of rhoifolin significantly diminished the TNF-α release in the inflammatory exudates. In the same animal model, rhoifolin increased the total antioxidant capacity in a reverse dose order, with the highest capacity obtained with the lowest dose tested. This study demonstrates for the first time the effectiveness of rhoifolin in combating inflammation in carrageenin-induced rat oedema model.