Antibacterial iridoid glucosides from Eremostachys laciniata

Abstract

Eremostachys laciniata (L) Bunge (family: Lamiaceae alt. Labiatae; subfamily: Lamioideae) is one of the 15 endemic Iranian herbs of the genus Eremostachys. A decoction of the roots and flowers of E. laciniata has traditionally been taken orally for the treatment of allergies, headache and liver diseases. Three antibacterial iridoid glucosides, phloyoside I (1), phlomiol (2) and pulchelloside I (3) have been isolated from the rhizomes of this plant. The structures of these compounds were elucidated unequivocally by a series of 1D and 2D NMR analyses. The antibacterial activity and brine shrimp toxicity of these compounds were assessed using the resazurin microtitre assay and the brine shrimp lethality assay, respectively. All three iridoid glycosides 1-3 exhibited from low to moderate levels (MIC = = = = = 0.05-0.50 mg/mL) of antibacterial activity. Of these compounds, compound 3 was the most active, and displayed antibacterial activity against 9 of 12 different strains tested. The most noteworthy activity of 3 was against Bacillus cereus, penicillin-resistant Escherichia coli, Proteus mirabilis and Staphylococcus aureus with an MIC value of 0.05 mg/mL.

Essential oil composition and isolation of freeradical-scavenging phenolic glycosides from the aerial parts of Ajuga chamaepitys growing in Iran

“…Previous phytochemical investigations on this plant revealed the presence of cloredan and neocloredan diterpenes in the aerial parts, and β-pinene and germacrene-D as the major components of the essential oils (Hernandez et al, 1980;Camps et al, 1984Camps et al, , 1987Boneva et al, 1990;Baser et al, 1999;Azizan et al, 2002;Velasco-Negueruela et al, 2004). In continuation of our phytochemical and pharmacological studies on the medicinal plants of the Iranian flora (Delazar et al, 2004(Delazar et al, , 2006(Delazar et al, , 2007(Delazar et al, , 2010a2011a,b;Babaei et al, 2008;Nazemieyh et al, 2008aNazemieyh et al, ,b, 2011Nazifi et al, 2008;Razvi et al, 2008Razvi et al, , 2011Modaressi et al, 2009;Asnaashari et al, 2010), we now report on the isolation, identification and free-radicalscavenging properties of three phenolic glycosides (1-3), and the composition of the essential oils of the aerial parts of Ajuga chamaepitys (L.) Schreb. growing in Iran.…”

Phytochemistry and bioactivity of Pedicularis sibthorpii growing in Iran

“…However the extracts of P. sibthorpii have never been evaluated for their biological activities. As part of our on-going phytochemical and bioactivity studies on Iranian medicinal plants (Delazar et al, 2004(Delazar et al, , 2006(Delazar et al, , 2007(Delazar et al, , 2010a2011a,b;Babaei et al, 2008;Nazemiyeh et al, 2008aNazemiyeh et al, ,b, 2011Nazifi et al, 2008;Razavi et al, 2008Razavi et al, , 2011Modaressi et al, 2009;Asnaashari et al, 2010;Pasdaran et al, 2012), we now report on the bioactivity of the extracts of P. sibthorpii Boiss. growing in Iran, and the isolation and identifi cation of three phenylethanoids [isomartynoside (3), martynoside (2), and verbascoside (1)], an iridoid (aucubin, 4), a fl avonoid (luteolin 7-O-β-D-glucopyranoside, 5) and mannitol (6) from the methanolic extract of this species.…”

Biological and Phytochemical Screening of Eremostachys azerbaijanica Rech.f. Aerial Parts

“…Traditional knowledge showed anti-inflammatory and analgesic effects of rhizomes of various species of Eremostachys (1). Previous investigations reported the other biological properties such as antioxidant, antimalarial, anti-bacterial, antidepressant, and antinociceptive activities (1)(2)(3)(4)(5)(6). Phytochemical studies on the extracts of some species of this genus have indicated the presence of different natural compounds.…”

“…Phytochemical studies on the extracts of some species of this genus have indicated the presence of different natural compounds. The rhizomes of E. laciniata were an important source of iridoid glycosides, flavonoids, and phytosterols (2,5,6). Ferulic acid derivatives, furanolabdane diterpene glycoside, iridoid glycosides, and phenylethanoid glycosides have been identified from the rhizomes of E. glabra (7)(8)(9).…”