Zeinab A. Kandil

Cytotoxic compounds from the leaves of Gaillardia aristata Pursh. growing in Egypt

Ten compounds, neopulchellin (1), 6α- hydroxyneopulchellin (2), β-sitosterol-3-O-β-D-glucoside (3), apigenin (4), quercitin (5), eupafolin (6), kaempferol-3-methoxy-7-O-α-L-rhamnoside (7), apigenin-7-O-β-D-glucopyranoside (8), α-amyrin (9) and β-sitosterol (10), were isolated from the leaves of Gaillardia aristata by applying bioassay guided fractionation. The cytotoxicity was traced against two human cancer cell lines (breast (MCF7) and colon (HCT116)). The highest cytotoxicity was revealed by compounds 1 and 2 (isolated from chloroform extract); with IC50 values of 0.43, 0.32 µg mL−1 against MCF7 and 0.46, 0.34 µg mL−1 against HCT116, respectively. Compounds 9 and 10 (isolated from the n-hexane extract) exhibited lower IC50 values of 3.05, 2.35 µg mL−1 against MCF7 and 3.05, 2.35 µg mL−1 against HCT116, respectively, while compounds 4–7 obtained from the ethyl acetate extract revealed the lowest cytotoxicity. Identification of the aforementioned compounds was carried out on the basis of their physico-chemical properties and spectral analysis (UV, EI/MS, 1D and 2D).

Triterpenes as uncompetitive inhibitors of α-glucosidase from flowers of Punica granatum L.

The α-glucosidase and maltase inhibitory effects of Punica granatum L. flowers (PGF) were investigated. The methanol extract (PGFMe), n-hexane extract (PGFH), chloroform extract (PGFC) and the remaining water fraction (PGFW) were assayed for their α-glucosidase and maltase inhibitory effects. PGFW showed potent α-glucosidase inhibition with IC50 of 0.8 μg/mL followed by PGFMe (IC50 of 4.0 μg/mL) then PGFC (IC50 of 5.21 μg/mL) in comparison to acarbose (0.9 μM). Due to its selectivity towards α-glucosidase, PGFC was subjected to bioactivity-guided isolation of its main active constituents. Five known compounds (1–5) were identified as β-sitosterol (1), oleanolic acid (2), ursolic acid (3), p-coumaric acid (4) and apigenin (5). Ursolic and oleanolic acids showed potent α-glucosidase inhibition (IC50 of 39.0 and 35.0 μM, respectively), while they did not show significant maltase inhibition. Kinetic study using the double Lineweaver–Burk plot revealed that ursolic acid uncompetitively inhibited α-glucosidase in comparison with acarbose as a competitive inhibitor.

Chemical composition and biological activities of the essential oil of Mentha suaveolens Ehrh.

Hydrodistilled oils of the fresh aerial parts of Mentha suaveolens Ehrh. cultivated in Egypt were prepared from samples collected along the four seasons. The percentage yields of these essential oils were 0.50%, 0.52%, 0.60%, and 0.47% of the dry weight for winter, spring, summer, and autumn samples. GC/MS analyses of all samples revealed a qualitative and quantitative variability in the oil composition. The total number of compounds identified was 46 among which 15 were common in all samples. The oxygenated compounds constituted about 45%, 46%, 63%, and 44% of the total composition of the oils for winter, spring, summer, and autumn samples, respectively. Carvone was the major constituent in spring, summer, and autumn samples (about 31%, 56%, and 35%, respectively), while limonene (ca. 26%) was the major constituent of the winter sample followed by carvone (ca. 25%). The essential oil of the highest yield (full-fl owering summer sample), with the highest oxygenated constituents and carvone contents, was screened for certain biological activities. It exhibited analgesic and acute anti-inflammatory activities (75% and 82% relative to indomethacin). It also showed a potent in vivo antioxidant activity (96% relative to vitamin E). In addition, it exerted moderate cytotoxic, hepatoprotective, and in vitro antioxidant activities. Moreover, the oil had a potent antifungal activity against Candida albicans (MIC = 4 μg/ml), Saccharomyces cerevisiae (MIC = 5.2 μg/ml), and Aspergillus niger (MIC = 6.8 μg/ml).

Antibacterial, antioxidant, and topical anti-inflammatory activities of Bergia ammannioides: A wound-healing plant

Abstract Context: Despite the traditional use of Bergia ammannioides Henye ex Roth. (Elatinaceae) for the treatment of wounds in India, there is a scarcity of scientific data supporting this use. Objective: The objective of this study is to assess wound-healing potentiality of the plant, to study pharmacological activities that may contribute in eliminating wound complications, and to investigate the biologically active fractions. Material and methods: The ethanolic extract (EtOH) of the aerial parts was fractionated to obtain n-hexane (HxFr), chloroform (ClFr), ethyl acetate (EtFr), and n-butanol (BuOH) fractions. EtOH and its fractions were formulated in strength of 5 and 10% w/w ointment and tested for wound-healing activity using the excision model. The topical anti-inflammatory, in vitro antioxidant, and antibacterial activities were evaluated. HxFr and EtFr were chemically investigated to isolate their constituents. Results: Application of EtOH, HxFr, and EtFr (10% w/w ointments) leads to 71.77, 85.62, and 81.29% healing of the wounds with an increase in the collagen content. HxFr had the strongest anti-inflammatory (64.5% potency relative to Voltaren®) and antibacterial activity (MIC = 104 μg/ml against Staphylococcus aureus), while EtFr showed the strongest antioxidant activity against DPPH, ABTS•+, and super oxide radical with an IC50 value of 10.25 ± 0.01, 66.09 ± 0.76, and 167.33 ± 0.91 µg/ml, respectively. β-Sitosterol, lupeol, cyclolaudenol, and cycloartenol were isolated from HxFr. Quercetin, ellagic acid, kaempferol-3-O-α-l-rhamnoside, and quercetin-3-O-α-l-rhamnoside were isolated from EtFr. Discussion and conclusion: Our study presents scientific evidence for the efficacy of B. ammannioides in enhancing wound healing, and the first isolation of cyclolaudenol and cycloartenol from Bergia.

Chemical and biological study of Mentha suaveolens Ehrh. cultivated in Egypt

Investigation of the different fractions of the ethanolic extract of the aerial parts of M. suaveolens growing in Egypt yielded nine compounds; two new triterpenes [3β-acetyl -22α-hydroxy ursa-12,20diene (compound 1) and 2α, 3β-dihydroxy-olean-18-en-29-oic acid (compound 7)] and nine known compounds: a sterol and its glucoside; β-sitosterol (compound 2) and β-sitosterol-3-O- β-D-glucoside (compound 4), a triterpene; oleanolic acid (compound 3), two monoterepenes; dihydrolimonene (compound 5) and 7-hydroxy-p-cymene (compound 6), two flavonoids; isoquercitrin (compound 8) and rutin (compound 9) which were isolated from M. suaveolens Ehrh. for the first time. The structures of the isolated compounds were identified by spectral data (UV, MS, 1D and 2D-NMR) and comparison with authentic samples. Moreover, the ethanolic extract showed potent analgesic activity as compared to indomethacin. The ethyl acetate fraction was the most potent as anti-inflammatory (88%), followed by the ethanolic extract (82.9%) as compared with indomethacin. The ethanolic extract and its four subfractions showed a moderate inhibitory activity against the tested human pathogenic bacteria.

A new triterpene and protective effect of Periploca somaliensis Browicz fruits against CCl4-induced injury on human hepatoma cell line (Huh7)

The potential hepatoprotective effect of the methanolic extract of Periploca somaliensis Browicz fruits, its different fractions (n-hexane, chloroform and n-butanol) and the major isolated compound ursolic acid was evaluated using the human hepatoma cell line (Huh7) based on the changes in the activity of aspartate aminotransferase, alanine transaminase, glutathione and superoxide dismutase. Each sample was tested at three different concentrations (1000, 100 and 10 μg/mL). All tested samples exhibited a potent concentration-independent cytoprotective effect relative to silymarin as a reference standard. Chromatographic fractionation of the chloroform-soluble fraction of the methanol extract of P. somaliensis Browicz fruits afforded two known triterpenes, namely ursolic acid, and 11α,12α-epoxy-3β-hydroxy-olean-13β,28-olide, and a newly discovered one, namely 3β-hydroxy-urs-11-en-13β,28-olide. The structures of the isolated compounds were elucidated by the analysis of 1D and 2D NMR spectral data.

Chemical composition of the essential oil and botanical study of the flowers of Mentha suaveolens

Abstract Context: Herbal medicines play a paramount role in the treatment of wide range of diseases, so there is a growing need for their quality control and standardization. Traditionally, histological and morphological inspections have been the usual methods to authenticate herbs intended for medicinal applications. Mentha suaveolens Ehrh. (Lamiaceae) is native to Africa Temperate Asia and Europe and its cultivated in Egypt. Objective: The macro- and micromorphology of the flowers of M. suaveolens Ehrh. cultivated in Egypt were studied to find the diagnostic characters of this species. In addition, the chemical composition of the essential oil of the flowers was also studied to define the chemotype of the plant. Materials and methods: Photographs of macro- and micromorphology were taken using Casio and Leica DFC500 digital cameras, respectively. In addition, the essential oil was prepared by hydrodistillation followed by gas chromatographic/mass spectrometric (GC/MS) analysis for identification of its components. Results: The macro- and micromorphological characteristics of M. suaveolens were determined. The yield of the essential oil obtained by hydrodistillation from M. suaveolens flowers was 1.7% calculated on dry weight basis. GC/MS analysis of the oil resulted in identification of 29 components, which amounted to 99.77% of the total oil composition. The major component was carvone (50.59%) followed by limonene (31.25%). Discussion and conclusion: The results obtained herein revealed for the macro, micromorphological and chemical composition characteristics of the flowers. The results of GC/MS analysis of the essential oil supported that M. suaveolens cultivated in Egypt could be categorized as carvone-rich chemotype since this compound pertained its high relative percentile.

PPARα and γ Activation Effects of New Nor-triterpenoidal Saponins from the Aerial Parts of Anabasis articulata

Anabasis articulata, traditionally used to treat diabetes, is rich in saponin content. This study was performed to investigate the agonistic effect of its saponins on peroxisome proliferator-activated receptor-α and peroxisome proliferator-activated receptor-γ in human hepatoma (HepG2) cells to explore the possibility of the involvement of these nuclear receptors in the mechanism of the antidiabetic effect of the plant. Chemical investigation of the n-butanol fraction resulted in the isolation of three new and one known 30-noroleanane triterpenoid saponins. The structures of the new compounds were elucidated as 3β-hydroxy,23-aldehyde-30-norolean-12,20(29)-dien-28-oic acid-28-O-β-D-glucopyranosyl ester (1: ), 3β-O-D-galactopyranosyl-23-aldehyde-30-norolean-12,20(29)-dien-28-oic acid-28-O-β-D-glucopyranosyl ester (2: ), and 3β-O-D-xylopyranosyl-30-norolean-12,20(29)-dien-28-oic acid 28-O-β-D-glucopyranosyl ester (3: ), while the known 30-nortriterpenoidal saponin was identified as boussingoside E (4: ). Although, the isolated saponins (1:  - 4: ) did not show > 1.5-fold activation of peroxisome proliferator-activated receptor-γ, but two of them (1: and 3: ) activated peroxisome proliferator-activated receptor-α to the higher extents of 2.25- and 1.86-fold, respectively. These results suggest that the reported antidiabetic action of the isolated saponins may not solely involve the activation of peroxisome proliferator-activated receptor-γ. However, the agonistic activity of the n-butanol fraction of A. articulata (1.71-fold induction) and two of its saponins (1: and 3: ) towards peroxisome proliferator-activated receptor-α may be beneficial in the cardiovascular condition that is closely associated with diabetes and other metabolic disorders.

Molluscicidal and Mosquitocidal Activities of the Essential Oil of Mentha suaveolens Ehrh. Cultivated in Egypt

Abstract: The percentage yield of the essential oil obtained by hydrodistillation from the air-dried powdered aerial parts of Mentha suaveolens Ehrh. cultivated in Egypt was 1.13 %. Nineteen components were identified by GC-MS analysis of the oil which constitute to 97.95 % of its total composition. The overall chromatographic profile of the essential oil appeared to be dominated by the oxygenated constituents (74.15 %) among which carvone was the major constituent (58.36 %) while the amount of identified hydrocarbons was 23.80 % among which limonene was the major constituent (10.10 %). The molluscicidal activity of the essential oil on adult and embryonic stages of Biomphalaria alexandrina was evaluated. The essential oil gave LD and 100 at 50 and 100 ppm/6hrs, respectively for adult snails. The essential oil also, showed 100 % ovicidal activity at 100 ppm/24hrs. The mosquitocidal activity of the essential oil on both larvae and pupae stages of Culex pipiens was also studied. The oil showed both larvicidal and pupicidal activity at the same concentrations (LD and LD at 50 and 100 ppm/3hrs, respectively).