Isolation and characterization of new secondary metabolites from Asphodelus microcarpus

Abstract

Phytochemical study of the ethanolic extract of Asphodelus microcarpus Salzm. et Viv. (Asphodelaceae) resulted in the isolation of two new compounds, methyl-1,4,5-trihydroxy-7-methyl-9,10-dioxo-9,10-dihydroanthracene-2-carboxylate (1), and (1R) 3,10-dimethoxy-5-methyl-1H-1,4-epoxybenzo[h]isochromene (2) as well as three known compounds; 3,4-dihydroxy-methyl benzoate (3), 3,4-dihydroxybenzoic acid (4), and 6-methoxychrysophanol (5). Compound 1 showed a potent activity against methicillin-resistant Staphylococcus aureus (MRSA) and Staphylococcus aureus with IC50 values of 1.5 and 1.2 µg/mL, respectively. Compound 3 showed antileishmanial activity with an IC50 value of 33.2 µg/mL. Compound 2 is the first isochromene possessing a highly strained 1,4-epoxy moiety. The structure elucidation of isolated metabolites was carried out using spectroscopic data, the absolute configuration of 2 based on optical rotation and electronic circular dichroism experiments and calculations.

Asphodosides A-E, anti-MRSA metabolites from Asphodelus microcarpus

“…This class of compounds contains derivatives that consist of the basic structure of a 9, 10-anthraquinone moiety (Bajaj and Ishimaru, 1999). In continuation of efforts to search for new antimicrobial metabolites from A. microcarpus using biological activity guided fractionation, several anthraquinones showed activity against both methicillin resistant Staphylococcus aureus (MRSA) and S. aureus (Ghoneim et al, 2014, 2013), and five new compounds (1–5) were isolated and their antimicrobial activities were evaluated Fig. 1.…”

Benzoic Acid Derivatives of Ifloga spicata (Forssk.) Sch.Bip. as Potential Anti-Leishmanial against Leishmania tropica

“…The results of this study revealed promising anti-promastigote potentials for both compounds. In previous studies, methyl 3,4-dihydroxybenzoate has been isolated from Asphodelus microcarpus, demonstrating leishmanicidal activity (LD 50 = 33.2 µg/mL) against L. donovani promastigotes [15]. Furthermore, this compound has also been reported from Piper glabratum and P. acutifolium to exhibit strong leishmanicidal activity (LD 50 13.8 µg/mL) against L. amazonensis [16].…”

“…Agathisflavone, camptothecin, quercetin, and sinefungin are phytochemicals which have been isolated from different medicinal plants and have exhibited promising anti-leishmanial potential [13]. Moreover, the investigated compound, methyl 3,4-dihydroxybenzoate, has been isolated from plants Piper glabratum, P. acutifolium, and Asphodelus microcarpus [14][15][16], and was found to be active against different strains of Leishmania. However, we are reporting, for the first time, the efficacy of methyl 3,4-dihydroxybenzoate and octadecyl benzoate against L. tropica, the most prevalent species of Leishmania in Pakistan.…”

A Comprehensive Review on the Medicinal Plants from the Genus Asphodelus

“…Although the leaf seems to have stronger antimicrobial activity in comparison with roots, in general, both exhibit weak or no antimicrobial/antifungal activity [20,48,49,70]; however, compounds isolated from root tubers extracts showed potent activity such as asphodelin A against S. aureus (MIC = 16 µg/mL), Escherichia coli (MIC = 4 µg/mL), Pseudomonas aeruginosa (MIC = 8 µg/mL), Candida albicans (MIC = 64 µg/mL) [19] and Botrytis cinerea (MIC = 128 µg/mL) and asphodoside B against MRSA (IC 50 = 1.62 μg/mL) [51]. Other isolated compounds from root extracts showed different biological activity; for instance, ramosin showed potent cytotoxic activity against leukemia cell lines [21], aestivin showed potent antimalarial activity against chloroquine-sensitive and resistant strains of Plasmodium falciparum with IC 50 of 0.8–0.7 μg/mL [21] and 3,4-dihydroxy-methyl benzoate exhibited anti-parasitic activity against Leishmania donovani promastigotes with IC 50 of 33.2 µg/mL [54]. …”