Analysis of the essential oil composition of three cultivated Nepeta species from Iran.

Essential oils (EOs) of three Iranian cultivated Nepeta species were investigated. The oils were obtained by hydrodistillation of air-dried plant materials at full flowering stage and analyzed by gas chromatography (GC) and gas chromatography coupled to mass spectroscopy (GC/MS). In total, 89 compounds were detected. In over 2 years, a number of constituents were identified in the EO of Nepeta binaloudensis first and second years (26 and 37, respectively), Nepeta cataria (25 and 32, respectively), and Nepeta assurgens (45 and 50, respectively). In the oils of N. binaloudensis, 4a-α,7-α,7a-α-nepetalactone (NL) 59.7% and 1,8-cineole (19.6%) during the first and second years, respectively, were the main constituents. The main components of N. cataria were 4a-α,7-α,7a-ß-NL (72.8%) and 4a-α,7-ß,7a-α-NL (73.9%) during the first and second years, respectively, and 4a-α,7-α,7a-α-NL (55.5%) and 1,8-cineole (24.1%) during the first and second years, respectively, were the main constituents of N. assurgens. The results showed that NLs isomers and 1,8-cineole were the main components of the oils of three cultivated Nepeta species.

Bioactive constituents from transformed root cultures of Nepeta teydea.

A phytochemical study of an extract from transformed root cultures of Nepeta teydea, induced by Agrobacterium rhizogenes, led to the isolation of the following new compounds: the sesquiterpene (-)-cinalbicol, the diterpene teydeadione (6,11,14-trihydroxy-12-methoxy-abieta-5,8,11,13,15-penten-7-one), a degraded C23-triterpene (teydealdehyde) and three fatty acid esters of lanosta-7,24-dien-3ß-ol. The propyl ester of rosmarinic acid was also isolated for the first time from a natural source. In addition, two dehydroabietane diterpenes, eight triterpenes and eighteen known phenolic compounds were obtained. The antifeedant, cytotoxic and phytotoxic activities of the isolated compounds have also been investigated.

The antioxidant, general toxicity and insecticidal activities of Nepeta scrophularioides Rech. f. extracts in different developmental stages.

The essence of the present study is to focus on the antioxidant, general toxicity and insecticidal properties of the extracts of Nepeta scrophularioides Rech.f. during different developmental (vegetative, flowering, post-flowering) stages. The samples were subjected to screening for their possible antioxidant activities by using 2, 2-diphenyl-1-picrylhydrazyl (DPPH) assay. The extracts of the flowering and the post-flowering stages showed higher antioxidant activity than those from the vegetative stage. The MeOH extracts of N. scrophularioides in different development stages were tested for cytotoxicity by brine shrimp toxicity assay. The result obtained for the bio assay was found to be significantly lethality. Among the samples, the extracts of flowering stage were found to be the most active with a LC50 value of 0.078 mg/mL. All three extracts showed significant insecticidal activity at the concentration of 20 mg/mL dose of test sample after 24 h. The extracts of vegetative and post-flowering were the most potent samples.

Anticandidal activity of the essential oil of Nepeta transcaucasica Grossh.

Hydrodistallation of the aerial parts of Nepeta transcaucasica Grossh. (Lamiaceae), collected in Agri, Dogubayazit Province, afforded an essential oil that was characterized by GC and GC/MS analyses. Twenty-seven compounds, representing 97.69% of the total oil composition, were identified, and 4aα,7α,7aß-nepetalactone (1; 39%), 4aα,7α,7aα-nepetalactone (2; 28%), and germacrene D (3; 15%) constituted the major components. The anticandidal effects of the oil were evaluated against seven Candida strains by using the broth microdilution method. The oil showed good inhibitory effects against C. glabrata and C. tropicalis at minimal inhibitory concentrations (MICs) of 0.09 and 0.375 mg/ml, respectively.