CE-DAD Determination of Scutellarein and Caffeic Acid in Abelia triflora Crude Extract.

A precise, accurate, selective and sensitive capillary electrophoresis method using a diode array detector was developed for the first time for the determination of both scutellarein (SLN) and caffeic acid (CAA) in prepared Abelia triflora extract. Electrophoretic analysis was performed using a background electrolyte solution consisting of borax buffer (40 mM, pH 9.2) and a 200-nm detection wavelength. This method was fully validated according to The International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH) guidelines. The method was linear in the concentration range 2.5-100 µg/mL and it allowed the determination of both compounds with high degree of recovery (%Er < 2%) and intra-day and inter-day precision (relative standard deviation values <2%) and method robustness was also assessed by the low values of %RSD < 2% obtained after small deliberate changes in the method parameters. The contents of SLN and CAA were calculated using both the external standard and standard addition methods. Analysis of the ethyl acetate fraction of A. triflora revealed that SLN and CAA were found in concentrations of 0.46 mg/g and 2.10 mg/g, respectively, in the ethyl acetate fraction and 0.29 and 1.32 mg%, respectively, in the dry plant leaves.

Hepatoprotective and cytotoxic activities of Anvillea garcinii and isolation of four new secondary metabolites.

Anvillea garcinii is a medicinal plant traditionally used for the treatment of dysentery, gastrointestinal troubles, hepatitis, lung disease, colds, digestive problems and pulmonary affections and in liver diseases. Four new sesquiterpene lactones, garcinamines A-D, along with seven known compounds, were isolated from the leaves of A. garcinii. This is the first report of the isolation of amino acid analogues of parthenolide-type sesquiterpene lactones from the family Asteraceae. Total ethanol extract of leaves as well as the chloroform and n-butanol fractions were tested for their hepatoprotective effect using the carbon tetrachloride liver toxicity model. The chloroform fraction, at a dose of 400 mg/kg, demonstrated a significant hepatoprotective effect comparable to silymarin in all serum and tissue parameters. The cytotoxicity of all extracts and compounds were evaluated against five human cancer cell lines: MCF-7, HCT-116, HepG2, Hela and A-549. The results indicated that the chloroform and n-butanol fractions and compounds 3, 4, 7 and 8 displayed significant cytotoxic activity against these cell lines.

Nepeta deflersiana attenuates isoproterenol-induced myocardial injuries in rats: Possible involvement of oxidative stress, apoptosis, inflammation through nuclear factor (NF)-κB downregulation.

BACKGROUND: Nepeta deflersiana (Lamiaceae) is a perennial herb used in the Saudi and Yemeni folk medicine as an anti-inflammatory, carminative, and antirheumatic agent. PURPOSE: This study explores the phytochemistry of the plant and the cardioprotective effect of N. deflersiana ethanolic extract (NDEE) against isoproterenol (ISP)-induced myocardial injury in rats. DESIGN/METHODS: Cardiac function, serum cardiac enzymes, myocardial antioxidants, inflammatory, and apoptotic biomarkers, and histopathological parameters were studied in ISP-injured Wistar rat heart tissues. RESULTS: To the best of our knowledge, this is the first study to report the isolation of nine secondary metabolites from this plant: 1α-hydroxy-7α,14α,18-triacetoxy-isopimara-8,15-diene (1), ß-sitosterol (2), lupeol (3), ursolic acid (4), 2,3-dihydroxy ursolic acid (5), caffeic acid (6), methyl rosmarinate (7), rosmarinic acid (8), and an irridoid glucoside 8-epi-7-deoxyloganic acid (9). To explain the mechanisms underlying the cardioprotective effect of NDEE, we evaluated the redox-sensitivity of NDEE in ISP-induced cardiac injury. The oral administration of NDEE (50 and 100 mg/kg b.w) prevented the depletion of endogenous antioxidants (CAT, SOD, NP-SH, and NO) and myocyte injury marker enzymes and inhibited lipid peroxidation (MDA, MPO). Moreover, NDEE downregulated the expression of pro-inflammatory cytokines (TNFα, IL-6, and IL-10) and apoptotic markers (caspase-3 and Bax) and upregulated the anti-apoptotic protein Bcl2. Furthermore, NDEE pretreatment significantly downregulated cardiac NF-κB (p65) expression, NF-κB-DNA binding activity, and MPO activity. Histological data showed that NDEE pretreatment reduced myonecrosis, edema, and infiltration of inflammatory cells and restored the architecture of cardiomyocytes. CONCLUSION: NDEE demonstrated strong antioxidant, cardioprotective, anti-inflammatory, and anti-apoptotic potential against myocardial damage. This further endorses the use of N. deflersiana in Yemeni folk medicine against cardiovascular diseases.

Evaluation of Antiulcer and Cytotoxic Potential of the Leaf, Flower, and Fruit Extracts of Calotropis procera and Isolation of a New Lignan Glycoside.

Calotropis procera is traditionally used for treating many diseases including ulcers and tumors. It was thus deemed of interest to investigate and compare the antiulcer and cytotoxic activities of C. procera leaf, flower, and fruit extracts in an attempt to verify its traditional uses. Phytochemical studies on the fruits, flowers, and leaves of C. procera, collected from the desert of Saudi Arabia, led to the isolation of one new lignan 7'-methoxy-3'-O-demethyl-tanegool-9-O-ß-d-glucopyranoside and five known compounds from the flowers, four compounds from leaves, and a flavonoid glycoside and a lignan glycoside from the fruits. The structures of compounds were determined by spectroscopic techniques. Ethanol extracts of the three parts of C. procera were evaluated for their antiulcer activity and we found that the leaf extract possessed a powerful antiulcer activity which could be considered as a promising drug candidate. All the extracts and the isolated compounds were evaluated for their cytotoxic activity against MCF-7, HCT-116, HepG-2, and A-549 human cancer cell lines. Compound 2 was highly active on all the cell lines, whereas compounds 5 and 11 were more selective on colon and liver cell lines. Compound 10 demonstrated a significant activity on liver and lung cancer cell lines.

Bioactivity and chemical characterization of Acalypha fruticosa Forssk. growing in Saudi Arabia.

Acalypha is an important genus of the Euphorbiaceae family. The genus is represented by five species in Saudi Arabia. Acalypha fruticosa Forssk. Fl. Aeg is traditionally used as a cure for stomachache, dyspepsia, rheumatism, dermatitis, and swellings of the body. The present study endeavors to provide a phytochemical and biological evaluation of the plant, with the aim of relating activity to constituting secondary metabolites in the plant. Column chromatographic separation of the methanol extract led to the isolation of four compounds namely 2-methyl-5,7-dihydroxychromone 5-O-ß-d-glucopyranoside 1, acalyphin 2, apigenin 3 and kaempferol 3-O-rutinoside 4. The plant extracts and the isolated compounds were subjected to biological assays to screen peroxisome proliferator-activated receptor alpha (PPARα) and PPARγ agonistic, anti-inflammatory and cytotoxic activities. Results proved for the first time, the PPARγ activator effect of acalyphin, as well as its promising anti-inflammatory activity, in addition to the dual PPAR activator effect of the chromone glucoside. The plant extracts and isolated compounds were non-cytotoxic to the tested cell lines. Thus A. fruticosa could be a valuable source of important therapeutics that may hold clinical prospect.

New ellagic acid derivative from the fruits of heat-tolerant plant Conocarpus lancifolius Engl. and their anti-inflammatory, cytotoxic, PPAR agonistic activities.

Conocarpus lancifolius (Combretaceae), is distributed in Riyadh, Saudi Arabia. It is a heat-tolerant Saudi medicinal plant, demonstrates prominent antidiabetic potential and the fruit extract fruits showed cytotoxicity against MRC-5 cancer cell line, as well as prominent antiprotozoal and antibacterial activities. The objective of this study is to isolate the compounds and evaluate the anti-inflammatory, cytotoxic, PPAR agonistic and antioxidant activities of extracts and pure constituents from C. lancifolius. A new trimethoxyellagic acid derivative 1 and two compounds, kaempferol 3-O-rutinoside 2 and ß-sitosterol glucoside 3 were isolated from the fruits of Conocarpus lancifolius, a heat-tolerant plant. Compound 2 showed strong dual activation for PPARα and PPARγ with 2.6 fold increment in PPARα activity, while 2.2 fold increment in PPARγ at 25µ/ml. This is first report on isolation and screening of different biological activities of extract and pure constituents from fruits of C. lancifolius.

Isolation of flavonoids from Delonix elata and determination of its rutin content using capillary electrophoresis.

Delonix elata (L.) Gamble (Fabaceae) is an important, traditionally used plant in Saudi Arabia. It is used to relieve rheumatic pain, flatulence and the seeds are employed as purgatives. The aim of the present study was to isolate chemical constituents of the n-butanol fraction (BF) of D. elata and to find out, by capillary electrophoresis (CE), percentage of rutin present in this BF. Three quercetin glycosides and one kaempferol rutinoside were isolated from the BF of aerial parts of D. elata; namely, Quercetin 3-O-rutinoside-7-O-glucoside (1), Quercetin 3,7-diglucoside (2), Quercetin 3-O-rutinoside (RUT) (3) and Kaempferol 3-O-rutinoside (4). Rutin, an active constituent has been reported to possess good pharmacological as well as therapeutic potentials. A sensitive and rapid procedure for quantitative determination of RUT by capillary electrophoresis was developed and its content was found to be 7.349 mg/gm, relative to n-butanol fraction and 18.373 mg%, relative to the dry powder of D. elata. The method could be recommended for approval and use in the pharmaceutical and food industries.

Phytochemical and biological evaluation of Buddleja polystachya growing in Saudi Arabia.

Several Buddleja species were the target of phytochemical and biological studies; however, nothing was reported concerning the chemistry of Buddleja polystachya Fresen. growing in Saudi Arabia. Sixteen constituents were isolated from the aerial parts of B. polystachya using various chromatographic techniques and were identified by the help of different spectral techniques including 1D, 2D NMR and mass spectrometry. Moreover, the different fractions were evaluated for their anti-inflammatory and hypoglycemic activities. The isobenzofuranone derivative (4-hydroxy-7-methylisobenzofuranone) (4), has been isolated for the first time from this natural source, B. polystachya, along with fifteen known compounds namely; phenolic fatty acid ester, 1'(4-hydroxyphenyl) ethanol ester of docosanoic (1), uvaol (2), sakuranetin (3), kumatakenin (5), cirsimaritin (6), 5-hydroxy-3,7,4'-trimethoxyflavone (7), oleanolic acid (8), herbacetin 3,7,8-trimethyl ether (9), ursolic acid (10), verbascoside (11), linarin (12), luteolin 7-O-ß-D-glucoside (13), luteolin 7-(6"-caffeoyl)-O-ß-D-glucopyranoside (14), luteolin (15), and 6-O-α-L-(4''-O-trans-cinnamoyl) rhamnopyranosylcatalpol (16). Regarding the biological activities investigated, the ethyl acetate fraction showed the most significant anti-inflammatory activity, followed by the n-butanol and the aqueous fractions. As for the petroleum ether and dichloromethane fractions, their anti-inflammatory effects were moderate. The highest hypoglycemic activity was possessed by the ethyl acetate fraction, followed by the dichloromethane fraction and the n-butanol fraction showed the weakest activity.

Cytotoxic glucosphingolipid from Celtis Africana.

BACKGROUND: Literature survey proved the use of the powdered sun-dried bark and roots of Celtis africana for the treatment of cancer in South Africa. OBJECTIVE: The aim of this study was to do further isolation work on the ethyl acetate fraction and to investigate the cytotoxic activities of the various fractions and isolated compound. MATERIALS AND METHODS: Cytotoxicity of petroleum ether, chloroform, ethyl acetate, n-butanol fractions and compound 1 were tested on mouse lymphoma cell line L5178Y using the microculture tetrazolium assay. RESULTS: One new glucosphingolipid 1 was isolated from the aerial parts of C. africana. The structure of the new compound was determined by extensive analysis by one-dimensional and two-dimensional nuclear magnetic resonance spectroscopy and mass spectrometry. The ethyl acetate fraction and compound 1 showed strong cytotoxic activity with an EC50 value of 8.3 µg/mL and 7.8 µg/mL, respectively, compared with Kahalalide F positive control (6.3 µg/mL). CONCLUSION: This is the first report of the occurrence of a cytotoxic glucosphingolipid in family Ulmaceae.

Cytotoxicity Assessment of Six Different Extracts of Abelia triflora leaves on A-549 Human Lung Adenocarcinoma Cells.

The present investigation was designed to assess the anticancer activity of six different leaf extracts (ethyl acetate, methanol, chloroform, petroleum ether, n-butanol, and water soluble) of Abelia triflora on A-549 human lung adenocarcinoma epithelial cells. A-549 cells were exposed to 10-1000 µg/ml concentrations of the leaf extracts of A. triflorafor 24 h and then percentage cell viability was assessed by 3-(4,5-dimethylthiazol-2yl)-2,5-biphenyl tetrazolium bromide (MTT) assay. The results showed that leaf extracts of A. triflora significantly reduced the viability of A-549 cells in a concentration-dependent manner. Decrease was recorded as 31% with ethyl acetate, 36% with methanol, 46% with chloroform, 54% with petroleum ether, 62% with n-butanol, and 63% with water soluble extracts at 1000 µg/ml each. Among the various plant extracts, ethyl acetate extract showed the highest decrease in the percentage cell viability, followed by methanol, chloroform, petroleum ether, n-butanol, and water soluble extracts. Our results demonstrated preliminary screening of anticancer activity of different soluble extracts of A. triflora extracts against A-549 cells, which can be further used for the development of a potential therapeutic anticancer agents.

Abeliaside, a new phenolic glucoside from Abelia triflora.

A new phenolic glucoside, abeliaside, along with four known compounds, 5,6,7,4'-tetrahydroxy flavones, caffeic acid, 4-O-caffeoylquinic acid and caffeic acid glucoside, was isolated from the leaves of Abelia triflora R. Br. (Caprifoliaceae). The structure of the new compound was elucidated by different spectroscopic techniques. Compounds 1-5 were assayed for their anticancer activities against two cancerous human cell lines, MCF-7 and PC-3 cells, and normal Vero cell line using the crystal violet staining method. From the results it could be seen that caffeic acid possessed the highest anticancer effect against MCF-7 (IC50: 17 µg/mL) and PC-3 (IC50: 20.1 µg/mL) compared to vinblastine sulphate as reference drug (IC50: 4.6, 2.8 µg/mL). The other compounds showed weak anticancer activity on both cell lines.

New flavonol glycosides from the leaves of Caragana brachyantha.

Two new flavonol glycosides, brachysides C and D, together with three known flavonol glycosides, were isolated from the leaves of Caragana brachyantha. The structures of brachysides C and D were elucidated on the basis of detailed spectroscopic analysis as quercetin 5-O-[α-L-rhamnopyranosyl-(1 → 6)-ß-D-glucopyranoside]-7-O-[α-L-rhamnopyranoside] and quercetin 5-O-[α-L-rhamnopyranosyl-(1 → 6)-ß-D-glucopyranoside]-7-O-[α-L-rhamnopyranoside]-4'-O-[α-L-rhamnopyranoside], respectively. The presence of flavonol tetra- and triglycosides bearing a sugar moiety at position 5 was the first report from this genus Caragana.

Anticancer activity of flavane gallates isolated from Plicosepalus curviflorus.

BACKGROUND: Previous investigation of the methanol extract of Plicosepalus curviflorus leaves led to the isolation of two new flavane gallates (1, 2), together with other compounds including quercetin (3). The stems of P. curviflorus are used traditionally for the treatment of cancer in Yemen. OBJECTIVE: The aim of this study was to evaluate the anticancer activity of the plant methanol extract as well as isolated compounds (1-3). MATERIALS AND METHODS: The human cancer cell lines used were; MCF-7, HepG-2, HCT-116, Hep-2, HeLa and normal, Vero cell line using the Crystal Violet Staining method (CVS). RESULTS: Quercetin (3) possessed the highest anticancer effect against all five cell lines (IC50 ranging from 3.6 to 16.2 µg/ml). It was followed by 2S, 3R-3, 3', 4', 5, 7-pentahydroxyflavane-5-O-gallate (1), with IC50 ranging from 11.6 to 38.8 µg/ml. The weakest anticancer activity was given by 2S, 3R-3,3',4',5,5',7-hexahydroxyflavane-3',5-di-O-gallate (2) with IC50 ranging from 39.8 to above 50 µg/ml, compared to vinblastine sulphate as reference drug. Colon, liver and breast cell lines seemed to be more sensitive to the tested compounds than the cervical and laryngeal cell lines. Concerning the cytotoxic effect on Vero cell line, the pentahydroxyflavane-5-O-gallate (1) showed the highest IC50 ( 138.2 µg/ml), while quercetin exhibited the lowest IC50 to Vero cells (30.5 µg/ml), compared to vinblastine sulphate as reference drug (IC50: 39.7 µg/ml). CONCLUSION: The results suggest the possible use of compounds 1 and 3 as anticancer drugs especially against colon and liver cancers.

New flavane gallates isolated from the leaves of Plicosepalus curviflorus and their hypoglycemic activity.

Two new flavane gallates were isolated from the leaves of Plicosepalus curviflorus. The structure of the new compounds was established as 2S,3R-3,3',4',5,7-pentahydroxyflavane-5-O-gallate (1) and 2S,3R-3,3',4',5,5',7-hexahydroxyflavane-4',5-di-O-gallate (2), respectively. In addition, seven known compounds (-)-catechin (3), quercetin (4), lupeol (5), ß-sitosterol (6), pomolic acid (7), ß-sitosterol 3-O-ß-d-glucopyranoside (8) and 4-methoxycinnamic acid (9) were reported for the first time from the genus Plicosepalus. Compounds 1, 2 and 3 were investigated for their hypoglycemic activity and showed significant hypoglycemic activity in Swiss Albino mice.

Bioactive phenolic amides from Celtis africana.

Nine compounds have been isolated for the first time from Celtis africana, namely trans-N-coumaroyltyramine (1), trans-N-feruloyltyramine (2), trans-N-caffeoyltyramine (3), lauric acid (4), oleic acid (5), palmitic acid (6), lupeol (7), ß-sitosterol (8) and oleanolic acid (9), respectively. Their structures have been elucidated by different spectroscopic techniques. The isolated compounds were screened for their antioxidant, anti-inflammatory and acetylcholinestrease enzyme inhibitory activities. Compounds 1-3 showed significant antioxidant and anti-inflammatory activities and weak to moderate acetylcholinestrease enzyme inhibition activity.

Antioxidant and urease inhibitory C-glycosylflavonoids from Celtis africana.

Two new C-glycosylflavonoids celtisides A (1) and B (2) have been isolated from n-butanol-soluble fraction of Celtis africana, along with five known C-glycosylflavonoids vitexin (3), orientin (4), isoswertiajaponin (5), isoswertisin (6), and 2″-O-rhamnosyl vitexin (7) reported for the first time from this species. Their structures were assigned from 1D and 2D NMR spectra. These compounds were investigated for biological activities and showed significant antioxidant and urease inhibitory activities.