El-Sayeda A. El-Kashoury

Cardenolide glycosides with doubly linked sugars from Gomphocarpus sinaicus

Abstract Five cardenolide glycosides and two genins, including two new glycosidic compounds, have been isolated for the first time from the chloroformic fractio

A new flavonol glycoside and biological activities of Adenanthera pavonina L. leaves

Adenanthera pavonina is a plant belonging to family Fabaceae. The 95% ethanol extract (EtOH) of the dried powdered leaves of the plant and successive extracts with solvents of increasing polarities were prepared. Fractionation of the successive aqueous EtOH extract on polyamide column and purification of the isolated compounds on Sephadex LH20 led to the isolation of a new methoxy flavonol glycoside named as quercetin 3-O-α-dirhamnopyranosyl-(1‴ → 2″,1″″ → 6″)-β-glucopyranoside-4′-methoxy (1), as well as kaempferol-3-O-α-dirhamnopyranosyl-(1‴ → 2″,1″″ → 6″)-β-glucopyranoside (2), isovitexin (3), quercetin-3-O-rhamnopyranosyl(1‴ → 4″)-β-glucopyranoside (4), quercetin-3-O-β-glucopranoside-4′-O-rhamnopyranoside (5), kaempferol-3-O-α-rhamnopyranosyl(1‴ → 2″)-β-glucopyranoside (6), quercetin-3-O-rhamnopyranosyl(1‴ → 2″)-β-glucopyranoside (7), quercetin-3-O-β-glucopyranoside (8), kaempferol (9) and quercetin (10). Structures of the isolated compounds were established by spectroscopic analysis. Antioxidant activities of EtOH extract, successive extracts and compounds 1 and 2 were evaluated. The ethyl acetate (EtOAc) extract and EtOH extract showed 62.67% and 49.30% free radical scavenging activity, respectively. Cytotoxic activities of the EtOH extract and compounds (1) and (2) were evaluated. The EtOH extract showed a significant cytotoxic activity against Hep G-2 (IC50 = 2.50 μg) as compared with cisplatin (IC50>10 μg).

Cardenolide glycosides from Gomphocarpus sinaicus

Abstract Two new cardenolide glycosides, one with a doubly-linked sugar, 15β-hydroxy-5,6-dehydrocalotropin and the other with a singly linked sugar, coroglaucigenin-3-(6-deoxy-β- d -allopyranoside)-19-acetate, were isolated from the chloroform extract of the stems of Gomphocarpus sinaicus. Two other known cardenolides, were also isolated and identified as 5,6-dehydrocalotropagenin and 16α-hydroxy-5,6-dehydrocalotropin. These compounds were isolated for the first time from G. sinaicus. Their identification was confirmed by 400 MHz1H and 13CNMR, and EI mass spectral analysis.

A comparative study of the cardenolide content of different organs of Gomphocarpus sinaicus

Abstract An examination of the various tissues of Gomphocarpus sinaicus revealed no remarkable differences in the cardenolide patterns of the plant organs (except seeds). 5,6-Dehydrocalotropin was found to be the main cardiac glycoside in all organs.

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).

Metabolites profiling of Chrysanthemum pacificum Nakai parts using UPLC-PDA-MS coupled to chemometrics

Methanol-soluble constituents from the flowers, non-flowering aerial parts and roots of Chrysanthemum pacificum Nakai were analysed via high resolution UPLC-PDA-qTOF-MS followed by chemometrics. Forty-seven chromatographic peaks belonging to various metabolite classes were detected. Most metabolite classes showed qualitative and quantitative differences across parts, with luteolin conjugates being mostly enriched in flowers whereas non-flowering aerial parts contained mostly quercetin and methoxylated flavone conjugates. Root sample ranked the lowest for all flavones and dicaffeoylquinic acids. In contrast, 1,5-di-caffeoylquinic acid levels were found at high levels in flowers and aerial parts reaching 3145 and 1390 μg/g, respectively, suggesting that C. pacificum could serve as a natural resource of this well-recognised anti-hepatotoxic phenolic. Principal component analysis was further used for organs classification in an untargeted manner. This study provides the first map of secondary metabolites distribution in C. pacificum Nakai organs.

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.

Evaluation of the phenolic content and antioxidant potential of Althaea rosea cultivated in Egypt

Objective The aim of this study was to evaluate the total phenolic content (TPC) and antioxidant potential of Althaea rosea Cav., family Malvaceae, as well as to isolate and identify the flavonoid content of the methanolic extract of the aerial parts. In addition, a comparison between the TPC and antioxidant capacity of the methanolic extract of both aerial parts and flowers was carried out to discover new active constituents that can be utilized in drug industry. Materials and methods The extraction of the flavonoid compounds was carried out by percolation of the dried aerial parts of the plant under investigation with 70% methanol until exhaustion. The combined extract was then concentrated and defatted with petroleum ether (60-80°C). After separation of the lipoidal matter, the remaining extract was purified from mucilage and subjected to several column chromatographic techniques for isolation of the flavonoids. The identification of flavonoid compounds was carried out using physical, chemical, and spectral methods such as ultraviolet, 1 H NMR, and 13 C NMR. The antioxidant potential of the methanolic extracts of both aerial parts and flowers was determined using the s[table 2], 2-diphenyl-1-picrylhydrazyl free radical scavenging activity method. Furthermore, their TPC was also determined using the Folin-Ciocalteu method. Results Five flavonoid compounds were isolated from the aerial parts of A. rosea Cav., which were identified as quercetin 3-O-β-d-glucuronopyranoside-8-C-β-d-glucopyranoside, kaempherol-3-O-β-d-rutinoside, kaempherol-4΄-O-β-d-glucoside, kaempherol-3-O-β-d-glucoside, and kaempherol. The antioxidant activity was measured in terms of their IC 50 . The IC 50 values of the methanolic extracts of the aerial parts and flowers were 11 and 1 mg/ml, respectively, whereas the TPCs were 48 and 73 μg/ml, respectively. Conclusion The methanolic extracts of both aerial parts and flowers of A. rosea Cav. are rich in phenolic compounds and have a prominent antioxidant activity. The antioxidant activity of both extracts may be attributed to their phenolic content.

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.

Comparative DNA profiling, phytochemical investigation, and biological evaluation of two Ficus species growing in Egypt.

Aim and Background: A comparison between two Ficus species, cultivated in Egypt, was carried out in this study. Their DNA analysis revealed that they are not closely related. Materials and Methods: The pharmacopoeial constants of the leaves showed higher total ash and acid insoluble ash in F. lyrata than in F. platypoda. The other parameters were close in both species. Preliminary phytochemical screening revealed the presence of carbohydrate and/or glycosides, tannins, flavonoids, sterols, and triterpenes in their leaves and was detected in traces in their stems. Results: Saponification of n-hexane extract of the leaves yielded 46% and 74.8% for the unsaponifiable matters and 20% and 15% for the fatty acids for F. platypoda and F. lyrata, respectively. n-Docosane (21.69%) and n-heptacosane (33.77%) were the major hydrocarbons in F. platypoda and F. lyrata, respectively. b-Sitosterol was the main sterol, palmitic (22.07%) and carboceric (35.72%) acids were the major identified saturated fatty acids in both species, while linoleic acid was the main unsaturated fatty acid (18.66% and 16.7%) in both species, respectively. The acute toxicity study revealed that the two species were safe up to 2 g/kg. The antioxidant activity using 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay and pyrogallol as the standard was more significant for F. platypoda (232.6 μg/ml) than for F. lyrata, (790.9 μg/ml). The oral antihyperglycemic activity in diabetic rats using alloxan revealed that the 80% ethanolic extract of the leaves of F. platypoda was more active than that of the leaves of F. lyrata in decreasing the blood glucose level at 200 mg/kg/day (107.9 ± 5.817, 127.2 ± 4.359) and 400 mg/kg/day (64.11 ± 4.358, 127.7 ± 6.889), respectively, when compared with the diabetic control gliclazide (172.3 ± 2.089). Conclusion: The results of this study provide evidence that the two Ficus species have antioxidant and antihyperglycemic activity, in the order F. platypoda and then F. lyrata