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Introduction GenuTs Astragalus L. is characterised by the presence of cycloartane saponins which have wide biological activities such as antioxidant, immunomodulating' hepatoprotective and anti-inflammatory activities. From these cycloartane saponins are astragalosides I, II and IV which have been regarded as the most important active constituents in Astragalus species. Objectives This work describes the quantitative analysis of astragalosides I, II and IV in some Egyptian Astragalus species and Astragalus dietary supplements in a single run by high-performance liquid chromatography/evaporative light scattering detector (HPLC/ELSD) using gradient elution. Methodology The method of quantitation adopted in this study is the standard addition method. First and second derivative treatment of the data was performed, and the study presents comparison between two statistical regression methods for handling data; parametric and non-parametric regression methods. Results Derivative treatment of the chromatographic response data gives improved quantitation of the chromatographic signals. Non-parametric regression of the data using Theil's method is advantageous over the usual least squares method as it assumes that errors could occur in both x- and y-directions and they might not be normally distributed. In addition, it could effectively circumvent any outlier data points. Conclusion Due to the simplicity and the good accuracy and reproducibility of the suggested methods, they could be used for analysis and quality control of Astragalus species and Astragalus dietary supplements.

Silymarin is a mixture of anti-hepatotoxic polyphenolic substances isolated from the milk thistle plant, Silybum marianum (L.) Gaertn. Silymarin is a static quencher, therefore, a new sensitive spe...

A new, simple, stability-indicating high-performance thin-layer chromatography method was developed for the quantification of 10-hydroxy-2-decenoic acid (10-HDA) in some royal jelly products marketed in Egypt. The used solvent system was chloroform:acetic acid (10:1, v/v) and the bands were measured densitometrically at 210 nm. First- and second-derivative treatments of the data were performed. The present study shows a comparison between three statistical regression methods for handling data: parametric, nonparametric and weighted regression (WR) methods. The developed methods were validated as per International Conference on Harmonization guidelines. To validate the stability-indicating power of the developed analytical method, the royal jelly standard was subjected to forced degradation studies including the effect of hydrolysis, oxidation, photolysis and dry heat. It was found that derivative treatment of the chromatographic response data gives improved quantitation and sensitivity of the chromatographic signals. Weighted regression of the response data is found to be advantageous over the use of both parametric and nonparametric regression models. This was shown by a great enhancement in the accuracy and precision in the analysis of 10-HDA in royal jelly products. The % recovery in case of WR was 99.92 ± 0.16, while % recovery in case of nonparametric and parametric regressions were 99.56 ± 0.25 and 98.63 ± 0.65, respectively.

GenuTs Astragalus L. is characterised by the presence of cycloartane saponins which have wide biological activities such as antioxidant, immunomodulating' hepatoprotective and anti-inflammatory activities. From these cycloartane saponins are astragalosides I, II and IV which have been regarded as the most important active constituents in Astragalus species.This work describes the quantitative analysis of astragalosides I, II and IV in some Egyptian Astragalus species and Astragalus dietary supplements in a single run by high-performance liquid chromatography/evaporative light scattering detector (HPLC/ELSD) using gradient elution.The method of quantitation adopted in this study is the standard addition method. First and second derivative treatment of the data was performed, and the study presents comparison between two statistical regression methods for handling data; parametric and non-parametric regression methods.Derivative treatment of the chromatographic response data gives improved quantitation of the chromatographic signals. Non-parametric regression of the data using Theil's method is advantageous over the usual least squares method as it assumes that errors could occur in both x- and y-directions and they might not be normally distributed. In addition, it could effectively circumvent any outlier data points.Due to the simplicity and the good accuracy and reproducibility of the suggested methods, they could be used for analysis and quality control of Astragalus species and Astragalus dietary supplements.

German Chamomile is known to be one of the most widely used plants in the growing market of herbal drugs due to its vast range of medicinal and therapeutic properties. The high demand on the plant raw material makes it prone to deliberate as well as unintentional adulteration by other morphologically-resembling flowers. Adulteration by potentially toxic plant-based adulterants imposes a great risk considering that German chamomile is widely incorporated in infants’ preparations. A methodology based on near infrared spectroscopy and chemometrics tools to authenticate, detect and quantify some of the common toxic adulterants of German chamomile is proposed in this work. Authentication of the plant was achieved with 100% sensitivity using soft independent modelling of class analogy SIMCA model. Discrimination of the plant from its deliberately-adulterated mixtures was accomplished using Orthogonal projection to latent structures-Discriminant analysis OPLS-DA model with 96% specificity. Partial least squares (PLS) regression models using variables selection based on variable’s importance were successfully constructed. A limit of detection (LOD) and a limit of quantification (LOQ) of less than0.5% (m/m) and 1% (m/m), respectively, was obtained for each adulterant in the powdered plant material. All the developed methods were comprehensively validated using an external test set which reflected their accuracy and robustness.

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.

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.

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.

Tomentoside I, a new tetranor-cycloartane triterpene glycoside was isolated fromAstragalus tomentosus. Its structure was established as 6α-acetoxy-23-ethoxy-16β,23(R)-epoxy-24,25,26,27-tetranor-9,19-cyclolanosta-3β-O-xyloside, on the basis of spectral evidence. 3-O-Methyl-chiro-inositol ether was also isolated and identified. The known compound, astragaloside II, previously isolated fromA. spinosus, was also identified.

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.

Astragalus spp. (Leguminosae) represent a valid rural crop of ecological importance in many countries, and some species serve as foodstuffs and pharmaceutical emulsifiers. Astragalus species are used in Chinese traditional medicine as antiperspirant, antihypertensive, antidiabetic, diuretic and tonic. The pharmacologically active constituents of these Astragalus are of two different types, polysaccharides and saponins, and the most interesting pharmacological properties are hepatoprotective, immunostimulant and antiviral. Astragalus species are a source of cycloartane type saponins, derived from cycloartenol by oxidation at C-6, C-16, C-20, C-23, C-24, followed by possible ring closures with the formation of a 20,24-epoxide (cycloastragenol or cyclogalegenin) or a 20,25-epoxide, or a 16,24-20,24- diepoxide (cycloalpigenin), or a 16,23-16,24-diepoxide (cycloorbigenin B). Approximatively 100 saponins mainly derivatives of the 20( R ),24( S ) form of cycloastragenol [3β,6α,25-tetrahydroxy-20( R ),24( S )-epoxy-9,19-cyclolanostane], (astragalosides or astraversianins), and more rarely of the 20( S ), 24( R ) form (cyclogalegenin), have been isolated. Some species also contain trihydroxyolean-12-ene saponins. Details on the isolation, purification and structural elucidation, along with recent results on the pharmacological properties of Astragalus cycloartane and oleanane saponins, will be discussed.

The essential oil of Cupressus sempervirens L. cones, prepared by steam distillation, was analysed by GC and GC-MS. Forty-nine compounds were identified, accounting for 98.8% of the oil. Its antimicrobial activity was tested against Staphylococeus aureus, Escherichia coli and Candida albicans.

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.

The aerial parts of Iphiona scabra afforded a complex mixture of sesquiterpene xylopyranosides. Separation of the peracetylated derivatives gave 10 compounds, seven eudesmane derivatives, a secoeudesmane and two sesquiterpene glycosides with new skeletons, named iphionane and isoiphionane. The biogenesis of these compounds is discussed.

A new saponin glycoside has been isolated from ASTRAGALUS TRIGONUS collected in Egypt and identified as 6-oxocycloartan-3beta,-16beta-di- O-glucopyranoside on the basis of an analysis of spectral data from the parent compound and its peracetate.

A spectrophotometric method is presented for assaying Senna and its preparations, for both total sennosides and total rhein glycosides content. The method ensures complete elimination of other minor non-carboxylic anthracene derivatives, as well as flavonoidal contaminants. The proposed method quantitates the actual total sennosides content, through the elimination of these contaminants, and through correction for the interference due to the coexistence of rhein with sennidins, in the final determinative step. This would eliminate false high figures for total sennosides by earlier procedures and reflects, perspectively, the actual potency of the assayed samples.

Aristolochia elegans of Egyptian origin has yielded the new bisbenzylisoquinoline (―)-temuconine, which is enantiomeric with the previously described (+)-temuconine obtained from Chilean Berberis valdiviana

The chloroform extract of the defatted leaves of Aristolochia elegans has yielded a bis-1-benzyltetrahydroisoquinoline alkaloid with one diphenyl ether link between rings C and C′. On the basis of spectroscopic analysis this has been identified as the previously unreported (−)-( R,R )-7′- O -methylcuspidaline.