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A phytochemical investigation of the alkaloidal content of the bulbs of Narcissus pseudonarcissus cultivated in Egypt resulted in the isolation of the alkaloid; 9-O-demethyl-7-O-methyllycorenine (5) in addition to the eight known alkaloids; homolycorine (1), 7-O-methyloduline (2), 7-O-methyllycorenine (3), hippeastrine (4), 9-O-demethylhomolycorine (6), galanthamine (7), haemanthamine (8) and lycorine. Structural determination of the isolated alkaloids was established by different spectral analyses (UV, MS, NMR and 2D-NMR). The isolation of 9-O-demethyl-7-O-methyllycorenine (5) is reported here for the first time from family Amaryllidaceae. The chemotaxonomic significance of the isolated alkaloids was also studied; six of the isolated alkaloids belong to the homolycorine series which is a distinctive feature for the section Pseudonarcissi. The alkaloids of the homolycorine series are absent from some tribes of the Amaryllidaceae, such as the Amaryllideae or Hemantheae. Moreover, all the Narcissus alkaloids of the homolycorine series display a B/C ring junction with a cis stereochemistry Furthermore, the antimicrobial activity of some isolated alkaloids has been studied. It is noteworthy that this is the first phytochemical and biological investigation to be carried out on the Amaryllidaceae plant N. pseudonarcissus grown in Egypt.

A new, validated, sensitive and cheap method for preliminary quantitative evaluation of acetylcholine esterase inhibitory activity is presented. The proposed method combines HPTLC with data analysis by means of image processing software. An in-situ TLC autobiographic method was employed in which regions of the TLC plate which contain acetylcholinesterase inhibitors show up as white spots against the yellow background. Bleaching of the yellow color, caused by substances with acetylcholinesterase inhibitory activity was observed and recorded using a digital camera. ImageJ, JustTLC and Sorbfil, three image processing programs were evaluated for quantitative measurements. For evaluation of the assay efficiency, acetylcholinesterase inhibitory activity of different Amaryllidaceae plant extracts was expressed as Standard Activity Coefficients (SACs), which are relative measures of the activity to the well known acetylcholinesterase inhibitor eserine. We attempted to validate the method according to the ICH guideline. Different statistical data revealed that all image analysis software are able to detect the acetylcholine esterase inhibitory activity at very low concentration levels with the ImageJ program being the best of all three tested software regarding sensitivity, linearity and precision.

The phytochemical investigation of the aerial parts of Astragalus annularis Forssk. and A. trimestris L., Fabaceae, growing in Egypt, resulted in the isolation of eight compounds, for the first time from these two species. These compounds were identified by chemical methods, NMR spectroscopy, UV spectroscopy as well as MS analysis. The antimicrobial activity of the isolated compounds were tested against Staphylococcus aureus, Esherichia coli and Candida albicans.A investigação química das partes aéreas de Astragalus annularis Forssk. e A. trimestris L., Fabaceae, do Egito, resultou no isolamento de oito compostos, pela primeira vez nestas duas espécies. Estes compostos foram identificados por métodos químicos, espectroscopia de RMN, espectroscopia UV, bem como análise de EM. A atividade antimicrobiana dos compostos isolados foi testada contra Staphylococcus aureus, Escherichia coli e Candida albicans.

A rapid, accurate, specific, repeatable and robust HPTLC method for the determination of lycorine in different Amaryllidaceae plant extracts is presented in this work. No article related to the HPTLC determination of lycorine in plant extracts has been reported in literature. Lycorine, a common alkaloid of family Amaryllidaceae, moreover, there have been some recent reports which reveal the interaction of lycorine with DNA and tRNA. It has, therefore, been to the interest of phytochemists to determine the content of this alkaloid in Amaryllidaceaous plants.

In this article, we report on the alkaloid profile and dynamic of alkaloid content and diversity in two Narcissus plants at different stages of development. The alkaloid profile of the two Narcissus species was investigated by GC/MS and HPTLC. Fifty eight Amaryllidaceae alkaloids were detected, and 25 of them were identified in the different organs of N. tazetta and N. papyraceus. The alkaloid 3-O-methyl-9-O-demethylmaritidine is tentatively identified here for the first time from the Amaryllidaceae family, and four alkaloids (tazettamide, sternbergine, 1-O-acetyllycorine, 2,11-didehydro-2-dehydroxylycorine) are tentatively identified for the first time in the genus Narcissus. The different organs of the two species analyzed showed remarkable differences in their alkaloid pattern, type of biosynthesis, main alkaloid and number of alkaloids. Lycorine-type alkaloids dominated the alkaloid, metabolism in N. papyraceus, while alkaloids of narciclasine-, galanthamine- and homolycorine-types were found only in the species N. tazetta L. Fil: Shawky, Eman. Alexandria University; Egipto Fil: Abou-Donia, Amina H.. Alexandria University; Egipto Fil: Darwish, Fikria A.. Alexandria University; Egipto Fil: Toaima, Soad M.. Alexandria University; Egipto Fil: Takla, Sarah S.. Alexandria University; Egipto Fil: Pigni, Natalia Belen. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Ciencia y Tecnología de Alimentos Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Ciencia y Tecnología de Alimentos Córdoba; Argentina Fil: Bastida, Jaume. Universidad de Barcelona; España

The work presented in this paper demonstrates the use of HPTLC-UV to quantify rutin in the alcoholic extract of Amaryllis belladonna L. (Family Amaryllidaceaea) flowers which was detected, isolated and identified in previous work. The results obtained by HPTLC showed excellent accuracy and precision when compared to the spectrophotometric method.

Four cycloartane-type saponins, kahiricosides II-V (1-4), were isolated from the aerial parts of Astragalus kahiricus of Egyptian origin. Their structures were established as 9beta,19-cyclolanost-24E-ene-3beta,6alpha,16beta,27-tetraol-3-O-beta-D-glucopyranoside, 9beta,19-cyclolanost-24E-ene-3beta,6alpha,16beta,27-tetraol-3-O-(2'-O-acetyl)-beta-D-glucopyranoside, 9beta,19-cyclolanost-24E-ene-3beta,6alpha,16beta,27-tetraol-3-O-(6'-O-acetyl)-beta-D-glucopyranoside, and 9beta,19-cyclolanost-24E-ene-3beta,6alpha,16beta,27-tetraol-3-O-beta-D-glucopyranosyl-27-O-beta-D-glucopyranoside based on chemical and spectral evidences. All compounds exhibited very weak cytotoxicity against the A2780 ovarian cancer cell line.

Three new cycloartane-type saponin ethyl acetals, deacetyltomentoside I (2), tomentoside III (3), and tomentoside IV (4), were isolated along with the known acetal tomentoside I (1) from the aerial parts of Astragalus tomentosus of Egyptian origin. The saponins from which the acetals are most probably derived are also new compounds. The structures of the acetals were established as 6alpha-hydroxy-23alpha-ethoxy-16beta,23(R)-epoxy-24,25,26,27-tetranor-9,19-cyclolanosta-3-O-beta-d-xyloside (2), 6alpha-acetoxy-23alpha-ethoxy-16beta,23(R)-epoxy-24,25,26,27-tetranor-9,19-cyclolanosta-3-O-[beta-d-(4'-trans-2-butenoyl)]xyloside (3), and 6alpha-acetoxy-23alpha-ethoxy-16beta,23(R)-epoxy-24,25,26,27-tetranor-9,19-cyclolanosta-3-O-[beta-d-glucopyranosyl(1 --> 2)]-beta-d-xyloside (4), by detailed spectroscopic and chemical studies.

From the roots of Astragalus kahiricus DC., three known saponins, namely, astraversianin VI, astraversianin X, astragaloside VIII, and a new saponin were isolated and identified by spectral data. The structure of the latter was elucidated by spectral means and assigned as cycloastragenol 3- O-[ beta- D-(2',3'-diacetyl, 4'- trans-2-butenoyl)-xylopyranosyl], 6- O- beta- D-xylopyranoside (kahiricoside I). From the aerial parts of A. hamosus L., the known compounds azukisaponin V and peregrinoside I were isolated. As judged by in vitro tests, the saponins isolated from Astragalus spp. endemic to Egypt were not cytotoxic against a variety of human cancer cells. However, dose-related modulation of lymphocyte proliferation was observed, and structure-activity relationships are described.

This study compares the chloroform extracts of bulbs and roots of Narcissus papyraceus Ker Gawl. and Narcissus tazetta L. The cytotoxicity of the plant extracts was evaluated against human hepatocellular carcinoma cell line (HEPG2) and colon carcinoma cell line (HCT116) in comparison to doxorubicin. The extracts from the after-flowering (AF) bulbs of N. tazetta L. and N. papyraceus exhibited strong cytotoxic activity against HEPG2 (IC50: 2.2, 3.5 μg mL(-1)) and HCT116 (IC50: 4.2, 3.9 μg mL(-1)) cell lines, respectively. N. tazetta L. bulbs exhibited the least cell viability percentage in HepG-2 cell line (5.32%), while the AF root extracts of N. papyraceus exhibited the least cell viability percentage in HCT116 cell line (4.93%), when applied at a concentration of 50 μg mL(-1), thereby being more active than doxorubicin at the same concentration.

The detailed investigation of Astralagus trigonus DC roots, led to the isolation of a new cycloartan-3β, 16β diglucoside, whose structure was elucidated by extensive use of 1D- and 2D- high field (600 MHz) NMR techniques. The NaBH 4 reduction of the natural 6-oxo 3β, 16β diglucoside, previously isolated from the same plant, afforded the 6-epi-derivative of the new compound. The conformational preference of both these compounds has been investigated by high field 1 H NMR spectroscopy and molecular modeling techniques.

Two new cycloartane saponins were isolated from the aerial parts of Astragalus sieberi. The structures were elucidated by 1D- and 2D- gradient-enhanced NMR analyses and enzymatic hydrolysis as 20(S),24(R)- epoxy -9β,19- cyclolanostan -3β,6α,16β,25- tetrol -3-O-β- d -glucopyranoside and 20(S),24(R)- epoxy -9β,19- cyclolanostan -3β,6α,16β,25- tetrol -3-O-β- d -glucopyranosyl -(1 → 2)-β- d - glucopyranoside .

The hepatoprotective activity of the ethanol extract of Astragalus kahiricus (Fabaceae) roots against ethanol-induced liver apoptosis was evaluated and it showed very promising hepatoprotective actions through different mechanisms. The extract counteracted the ethanol-induced liver enzymes leakage and glutathione depletion. In addition, it demonstrated anti-apoptotic effects against caspase-3 activation and DNA fragmentation that were confirmed by liver histopathological examination. Moreover, the phytochemical study of this extract led to the isolation of four cycloartane-type triterpenes identified as astrasieversianin II (1), astramembrannin II (2), astrasieversianin XIV (3), and cycloastragenol (4). The structures of these isolates were established by HRESI-MS and 1D and 2D NMR experiments. The antimicrobial, antimalarial, and cytotoxic activities of the isolates were further evaluated, but none of them showed any activity.

Alexandroside I, a new cycloartane triterpene glycoside was isolated from Astragalus alexandrinus. Its structure was established as 3-O-β- d -glucopyranosyl-9β,19-cyclolanost-3β,6α,16β,24(R),25 pentaol on the basis of spectroscopic and chemical methods. Four known glycosides, astraversianins VI, X, XIV and XV, were also isolated.

The phytochemical investigation of the aerial parts of Astragalus annularis Forssk. and A. trimestris L., Fabaceae, growing in Egypt, resulted in the isolation of eight compounds, for the first time from these two species. These compounds were identified by chemical methods, NMR spectroscopy, UV spectroscopy as well as MS analysis. The antimicrobial activity of the isolated compounds were tested against Staphylococcus aureus, Esherichia coli and Candida albicans. A investigação química das partes aéreas de Astragalus annularis Forssk. e A. trimestris L., Fabaceae, do Egito, resultou no isolamento de oito compostos, pela primeira vez nestas duas espécies. Estes compostos foram identificados por métodos químicos, espectroscopia de RMN, espectroscopia UV, bem como análise de EM. A atividade antimicrobiana dos compostos isolados foi testada contra Staphylococcus aureus, Escherichia coli e Candida albicans.

The work reported in this paper aims at developing an accurate, specific, repeatable and robust HPTLC method for the determination of galanthamine in different Amaryllidaceae plant extracts.

A phytochemical investigation of the bulbs and flowers of Hymenocallis littoralis SALISB., cultivated in Egypt, was carried out, which resulted in the isolation of four alkaloids, lycorine (1), hippeastrine (2), 11-hydroxyvittatine (3), and (+)-8-O-demethylmaritidine (4), and of two flavonoids, quercetin 3'-O-glucoside (5), and rutin (6). The volatile constituents of the plant flowers were analyzed for the first time by GC/MS, which led to the identification of 26 known compounds (Table 1). Finally, the antimicrobial activity of the petroleum ether extract of the flowers of H. littoralis was investigated.

Four cycloartane-type saponins, kahiricosides II–V (1–4), were isolated from the aerial parts of Astragalus kahiricus of Egyptian origin. Their structures were established as 9β,19-cyclolanost-24E-ene-3β,6α,16β,27-tetraol-3-O-β-d-glucopyranoside, 9β,19-cyclolanost-24E-ene-3β,6α,16β,27-tetraol-3-O-(2′-O-acetyl)-β-d-glucopyranoside, 9β,19-cyclolanost-24E-ene-3β,6α,16β,27-tetraol-3-O-(6′-O-acetyl)-β-d-glucopyranoside, and 9β,19-cyclolanost-24E-ene-3β,6α,16β,27-tetraol-3-O-β-d-glucopyranosyl-27-O-β-d-glucopyranoside based on chemical and spectral evidences. All compounds exhibited very weak cytotoxicity against the A2780 ovarian cancer cell line.

From Astragalus peregrinus, four cycloartane-type saponins have been isolated and their structures elucidated by spectral means as 20(R),24(S)-epoxy-9 beta,19-cyclolanostane-3 beta,6 alpha,16 beta,25-tetrol 3-O-beta-D-glucopyranoside (1), 20(R),24(S)-epoxy-9 beta,19-cyclolanostane-3 beta,6 alpha,16 beta,25-tetrol 3-O-alpha-L-rhamnopyranosyl-(1--4)-beta-D-glucopyranoside (2), 20(R),24(S)-epoxy-9 beta,19-cyclolanostane-3 beta,6 alpha,16 beta,25-tetrol 3-O-alpha-L-rhamnopyranosyl-(1--2)-beta-D-glucopyranoside (3) and 20(R),25-epoxy-9 beta,19-cyclolanostane-3 beta,6 alpha,16 beta,24(S)-tetrol (24-O-acetyl)- 3-O-alpha-L-rhamnopyranosyl-(1--2)-(6'-O-acetyl)-beta-D-glucopyranoside (4). Compounds 2 and 3 showed to stimulate the proliferation of mouse splenocytes and were not significantly cytotoxic.

Three new cycloartane glycosides, trigonoside I, II and III, and the known astragalosides I and II were isolated from the roots of Astragalus trigonus . The structures of the new glycosides were totally elucidated by high field (600 MHz) NMR analyses as cycloastragenol-6- O - β -xylopyranoside, cycloastragenol-3- O -[ α -l-arabinopyranosyl(1 → 2)- β -d-xylopyranosyl]-6- O - β - d-xylopyranoside and cycloastragenol-3- O -[ α -l-arabinopyranosyl(1 → 2)- β -d-(3- O -acetyl)-xylopyranosyl]-6- O - β -d-xylopyranoside.

Two new antimicrobial isoflavans, 1-[(3R)-7,8-dimethoxybenzopyranyl]-4-hydroxybenzoquinone (astragaluquinone) and (3S)-7,1′-dihydroxy-8,3′-dimethoxyisoflavan (8-methoxyvestitol), and the known 7-hydroxy-2′,3′,4′-trimethoxyisoflavan were isolated from roots of Astragalus alexandrinus and A. trigonus. The structures of the new isoflavans were established by spectroscopic methods.

Phytochemical investigation of the roots of Astragalus spinosus Forssk (Fabaceae) resulted in the isolation of ten metabolites. The structure of spinocoumarin I (1), a new coumarin derivative, was established as 3-[( cis-2′,5′-dihydroxycinnamoyl)]-7-hydroxy-6-methoxycoumarin. The structures of the isolated compounds were determined using spectroscopic methods. All compounds exhibited weak antiproliferative activity against the A2780 ovarian cancer cell line.