In vitro antioxidant and antiproliferative activities of flavonoids from Ailanthus excelsa (Roxb.) (Simaroubaceae) leaves.

The present study aimed to investigate the chemical composition, and the antioxidant and antiproliferative activities of Ailanthus excelsa, a plant used in Egyptian traditional medicine. Chromatographic separation of a methanol extract of A. excelsa leaves yielded four flavones, namely apigenin (1), apigenin 7-O-beta-glucoside (2), luteolin (3), and luteolin 7-O-beta-glucoside (4), and seven flavonols, namely kaempferol (5), kaempferol 3-O-alpha-arabinoside (6), kaempferol 3-O-beta-galactoside (7), quercetin (8), quercetin 3-O-alpha-arabinoside (9), quercetin 3-O-beta-galactoside (10), and quercetin 3-O-rutinoside (11). The A. excelsa extract tested in different in vitro systems (DPPH and FRAP assays) showed significant antioxidant activity. The potential antiproliferative activity of the A. excelsa extract and isolated flavonoids against five human cancer cell lines such as ACHN, COR-L23, A375, C32, and A549 was investigated in vitro by the SRB assay in comparison with one normal cell line, 142BR. The extract exhibited the highest inhibitory activity against C32 cells with an IC50 value of 36.5 microg ml(-1). Interesting activity against COR-L23 was found with 10 (IC50 value of 3.2 microg ml(-1)). Compounds 1 and 3 inhibited cell growth in both amelanotic melanoma and malignant melanoma cells.

Antioxidant and antiproliferative activity of Diospyros lotus L. extract and isolated compounds.

The object of the study was to determine the chemical composition of Diospyros lotus L. extract and their antioxidant and antiproliferative properties. Eight compounds were isolated from D. lotus and identified as gallic acid, methylgallate, ellagic acid, kaempferol, quercetin,myricetin, myricetin 3-O-beta-glucuronide, and myricetin-3-O-alpha-rhamnoside. D. lotus extract tested in different in vitro systems (DPPH, ABTS, FRAP, and Fe2+ chelating activity assay) showed significant antioxidant activity. The potential antiproliferative properties of D. lotus extract and isolated compounds against nine human cancer cell lines such as COR-L23, CaCo-2, C32, ACHN, A375, A549, Huh-7D12, MCF-7, and LNCaP were investigated in vitro by SRB assay. D. lotus extract demonstrated the highest inhibitory activity against COR-L23 with an IC50 value of 12.2 microg/ml. Among identified hydrolysable tannins, ellagic acid evidenced strong antiproliferative activity against both C32 and A375 cells with IC50 values of 0.8 and 4.1 microg/ml, respectively. Interesting results were observed, also, with gallic acid that showed the highest cytotoxic activity against CaCo-2 (IC(50) 2.6 microg/ml). Overall, the results of this study suggest that D. lotus displays a good antioxidant activity and has antiproliferative effects. Both activities are related to identified phenolic compounds.

Zizyphus jujuba and Origanum majorana extracts protect against hydroquinone-induced clastogenicity.

Hydroquinone (HQ) is a myelotoxin that is found in many foods and formed through the metabolism of benzene. HQ is genotoxic in several in vitro and in vivo test systems, inducing micronuclei (MN), sister-chromatid exchange (SCE), and chromosomal aberrations. The aim of the current study was to explore the protective effect of Zizyphus jujuba and Origanum majorana extracts against HQ-induced genotoxicity in male mice. Five groups of mice included the control group, HQ-treated group, and the groups treated with the extracts alone or in combination with HQ. The results indicated that treatment with HQ resulted in significant clastogenetic effects and histological changes typical to those reported in the literature. Both extracts exhibited a protection against HQ-induced cytogenesis and histological changes. Moreover, Z. jujuba extract was effective than O. majorana extract. It could be concluded that both extracts are useful especially for people who are occupationally exposed to benzene or its metabolites.

Anti-plasmodial activity of Ailanthus excelsa.

The anti-plasmodial activity of Ailanthus excelsa stem bark was investigated. The methanolic extract inhibited in vitro growth of chloroquine-sensitive (D10) and resistant strains (W2) of Plasmodium falciparum (IC50 4.6 and 2.8 microg/ml, respectively). The effect was retained in the chloroform fraction (3.1 and 2.1 microg/ml, respectively). The anti-plasmodial activity could be ascribed to the impairment of haemoglobin degradation through the inhibition of plasmepsin II activity (IC50 of 13.43+/-1.74 microg/ml) and of the haem detoxification to haemozoin.

Phenolic contents and bioactivities of pericarp and seeds of Pleiogynium solandri (Benth.) Engl. (Anacardiaceae).

OBJECTIVES: This study aimed to develop drugs from natural sources to overcome the side effects of many of synthetic drugs. Methanol extracts of both pericarp and seeds of Pleiogynium solandri were used to investigate antioxidant, hepatoprotective, and renal function protective, analgesic, and anti-inflammatory effects and to determine the chemical composition of the extract responsible for bioactivity. MATERIALS AND METHODS: Methanol (70%) extracts of the seeds and pericarps of P. solandri were prepared. Hot plate method was used to test analgesic activity, carrageenan-induced paw inflammation method was used to test anti-inflammatory activity, and colorimetric methods were used to test antioxidant, hepatoprotective (by determination of serum alanine and aspartate aminotransferase activities), and renal function protective effects (by measuring uric acid and creatinine levels). Chromatographic methods and means of (1)H-NMR, (13)C -NMR, and UV spectra were used for isolation and identification of the responsible compounds. RESULTS: In this study for the first time, four phenolic compounds were isolated from the pericarp of P. solandri which were identified as catechin, quercetin, quercetrin and rutin. Methanolic extract of both seeds and pericarp of P. solandri showed strong antioxidant effect, hepatoprotective, renal function protective, analgesic, and anti-inflammatory effects. However, seed extract had lower effect than pericarp in a dose dependent manner. CONCLUSION: This study showed that methanol extract of pericarp of P. solandri is more powerful than that of the seed regarding its antioxidant, hepato-protective; renal function protective, analgesic, and anti-inflammatory effects. The phenolic compounds isolated from the methanol extract of pericarp were responsible for bioactivity.

In vitro cancer cell growth inhibition and antioxidant activity of Bombax ceiba (Bombacaceae) flower extracts.

The flowers of Bombax ceiba were investigated for their chemical composition, antioxidant effects and antiproliferative activity against seven human cancer cell lines. The antiproliferative responses of diethyl ether (DE) and light petroleum (PE) extracts were evaluated by sulforhodamine B (SRB) assay against MCF-7, HeLa, COR-L23, C32, A375, ACHN, and LNCaP cells in comparison with a human normal cell line, 142BR. Moreover, extracts were characterized by GC-MS analysis and tested for their antioxidant properties by different in vitro systems, namely DPPH, Fe-chelating activity and beta-carotene bleaching test. Both PE and DE extracts showed the highest antiproliferative activity against human renal adenocarcinoma (ACHN) in a concentration-dependent manner. PE extract showed the highest radical scavenging activity against the DPPH radical, while DE extract was more active in the beta-carotene bleaching test. The presence of beta-sitosterol and some fatty acids may contribute to the bioactivity of B. ceiba flower extracts.

Gastroprotective and antisecretory effects of Ailanthus excelsa (Roxb).

Ailanthus excelsa (Roxb), an Egyptian medicinal species highly important for treating numerous diseases, was investigated against experimentally induced gastric ulcer in rodents. We evaluated the gastroprotective effect of four extracts (petroleum ether, diethyl ether, chloroform, and methanol) of A. excelsa bark by using the ethanol-induced gastric lesion model. The pretreatment of animals with methanolic, petroleum ether, and chloroformic extracts (100 mg/kg, oral (p.o.)) from A. excelsa significantly reduced gastric lesion induced by ulcerogenic agent (56, 47, and 70%, respectively) when compared with animals pretreated with vehicle. However, the diethyl ether pretreatment led to the least gastric lesion damage (83%), similar to the standard antiulcer drug, cimetidine, at the same dose (100 mg/kg, p.o.). The lower effective dose of diethyl ether extract, as well as cimetidine, given by intraduodenal route, significantly increased the pH values and reduced the acid output of gastric juice. Sterols, triterpenes,and quassinoids are present in the diethyl ether extract of A. excelsa stem bark, which presented the best gastroprotective action among the studied extracts. Our study confirmed the traditional indications of A. excelsa for the treatment of gastric ulcer.

Antioxidant activity of methanolic extract of Bombax ceiba.

The antioxidant activity of a methanolic extract of Bombax ceiba was evaluated using several antioxidant assays, in terms of its: (i) ability to scavenge DPPH (1,1-diphenyl-2-picryl-hydrazyl) and hydroxyl free radicals; (ii) action against lipid peroxidation (in rat liver microsomes and soy bean phosphatidylcholine liposomes), induced by ascorbyl radicals and peroxynitrite; and (iii) effect on myeloperoxidase activity. The cytotoxicity was monitored through the mitochondrial activity in the Vero cell line. The extract showed antioxidant activity in all assays, the EC(50) (microg/ml) for DPPH was 87 and for lipid peroxidation of microsomes and soy bean liposomes induced by ascorbyl radicals were 141 and 105, respectively, and by peroxynitrite were 115 and 77, respectively. The K(0.5) value for myeloperoxidase activity inhibition by the extract was 264 microg/ml. The extract showed very low toxicity toward Vero cells.

Inhibition of angiotensin converting enzyme (ACE) by flavonoids isolated from Ailanthus excelsa (Roxb) (Simaroubaceae).

In our screening program for antihypertensive properties of plants, the leaves of Ailanthus excelsa (Roxb), a plant used in Egyptian traditional medicine, were analysed. Chromatographic separation of A. excelsa MeOH extract yielded six flavonoids for the first time from this species, namely apigenin, luteolin, kaempferol-3-O-alpha-arabinopyranoside, kaempferol-3-O-beta-galactopyranoside, quercetin-3-O-alpha-arabinopyranoside and luteolin-7-O-beta-glucopyranoside. The in vitro hypotensive activities of the MeOH extract and the isolated compounds were elucidated. All the flavonoids tested exhibited ACE inhibitory activity, in particular the most active compound was kaempferol-3-O-beta-galactopyranoside with an IC(50) value of 260 microm.