Bioactive Constituents of Ziziphora clinopodioides

Extensive analysis of the cultivated medicinal herbal drug Origanum dictamnus L. and antimicrobial activity of its constituents

Phytochemical investigations of the methanol extract from Origanum dictamnus L. (Lamiaceae) resulted in the isolation of forty compounds belonging to the classes of terpenes, resorcinol derivatives, flavonoids, depsides, neolignans and jasmonates. Chromatographic isolations were targeted by using two analytical platforms, NMR and HPLC-PDA-MS. In parallel, HPLC-PDA-MS of individual fractions enabled the unambiguous identification of additionally eight components. In total 48 constituents were isolated/identified. Among the isolated constituents are four undescribed compounds, one resorcinol derivative, one monoterpene, one diterpene and one acylated flavonoid glycoside. The structures of the isolated compounds were elucidated on the basis of spectroscopic analyses, including 1D and 2D NMR, and HPLC-ESI-MS and HRMS experiments. Representative compounds were tested for their antimicrobial activity against Staphylococcus aureus and Pseudomonas aeruginosa. I4-II7-dicarvacrol was the most potent constituent.

The variability of phenolic constituents and antioxidant properties among wild populations of Ziziphora clinopodioides Lam

In this study, phenolic derivatives and antioxidant activities of fourteen Ziziphora clinopodioides populations, as well as LC-MS/MS analysis of three specific flavonoids were evaluated. Generally, high contents of phenolic derivatives were found in shoot extracts compared to roots. LC-MS/MS, a powerful analytical technique, was employed for the identification and quantify the individual flavonoids in Z. clinopodioides populations' extracts, in a quantity order of quercetin > rutin > apigenin. Scavenging activity by DPPH and FRAP was performed, and accordingly, in the shoot, the highest values for the DDPH were 4.61 ± 0.4 and 7.59 ± 0.26 µg ml- 1 in populations 1 and 13, respectively, and for the FRAP were 328.61 ± 5.54 and 292.84 ± 2.85 mg g DW- 1, in populations 6 and 1 respectively. Multivariate analysis results of the principal component analysis indicated the amount of polyphenols to be useful indicators in differentiating the geographical localities which explain 92.7% of the total variance. According to the results of hierarchical cluster analysis, the studied populations could be separated into two groups in that the contents of phenolic derivatives and antioxidant activities of different plant parts. Both shoot and root samples were well discriminated with the orthogonal partial least squares discriminant analysis (R2X: 0.861; Q2: 0.47) model. The validity of the model was confirmed by using receiver operating characteristic curve analysis and permutation tests. Such data make an important addition to our current knowledge of Ziziphora chemistry and are decisive in the identification of germplasms with a homogeneous phytochemical profile, high chemical content and bioactivity. The present results could also be helpful for the potential application of Z. clinopodioides in different kinds of industries as natural antioxidants.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12298-023-01283-y.

Phenols from Origanum dictamnus L. and Thymus vulgaris L. and their activity against Malassezia globosa carbonic anhydrase

Malassezia spp. are lipophilic fungi that are part of the normal flora of the human skin and are the etiological agents of dandruff and seborrheic dermatitis. β-Carbonic Anhydrases (CAs; EC 4.2.1.1) expressed from the pathogenic fungi are an alternative/complementary drug target. Previous work by our groups demonstrated that flavonoids and depsides can effectively inhibit Malassezia globosa β-CA (MgCA). In continuation of this study herein we report the inhibitory activity of a variety of phenols from Origanum dictamnus L. and Thymus vulgaris L. against β-MgCA, among them I4-II7-di-carvacrol, a new natural product. Structure elucidation of the compounds was performed by 1 D, 2 D NMR and spectrometric analyses. Xanthomicrol and rosmarinic acid were active in the (sub)micromolar range (K_IS 0.6 and 2.2 μM, respectively vs 40.0 μM of the standard inhibitor acetazolamide). Finally, the compounds were not cytotoxic, but showed in vitro no activity against Malassezia furfur.

Study on the Chemical Composition, Enzyme Inhibition and Antioxidant Activity of Ziziphora taurica subsp. cleonioides

Ziziphora is a plant used in Turkish and Iran traditional medicine for its antibacterial activity, sedative and stomach soothing properties. Although the chemical profile of the essential oil of different Ziziphora species is well documented, data regarding plant extracts are incomplete. In this study extracts from Ziziphora taurica subsp. cleonioides were obtained using ethyl acetate, methanol and water and the chemical profile of the aerial part of the plant was elucidated. Among the compounds identified, rosmarinic acid was the most abundant (3375.67 ± 38.02 μg/mL), at the extract of methanol, followed by chlorogenic acid (3225.10 ± 16.44). Enzyme inhibition activity against α-amylase and tyrosinase was also estimated. The ethyl acetate extract showed the highest α-amylase activity (1.95 ± 0.04 mg/mL), while the best anti-tyrosinase activity was calculated for the methanolic extract (1.25 ± 0.01 mg/mL). In addition, total phenolic, flavonoid content and antioxidant activity were evaluated. According to our results, bioactivity of the plant is of great interest, nonetheless, at the same time, it is strongly depended on the solvent used during the extraction process. Our data suggest that the plant under study may be an important source to consider against metabolic, skin pigmentation and oxidative stress related disorders.