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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.

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.

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.

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.

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.

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.