Composition of the Essential Oil ofPhlomis nissoliiL

Glandular Trichomes and Essential Oils Variability in Species of the Genus Phlomis L.: A Review

The genus Phlomis is one of the largest genera in the Lamiaceae family and includes species used since ancient times in traditional medicine, as flavoring for food and as fragrance in cosmetics. The secretory structures (represented by glandular trichomes) as well as the essential oils produced by them constitute the subject of this review. While representatives of this genus are not typically regarded as large producers of essential oils compared to other species of the Lamiaceae family, the components identified in their essential oils and their biological properties necessitate more investigation of this genus. A comprehensive analysis of the specialized literature was conducted for each of the 93 currently accepted species to identify all the results obtained by researchers regarding the secretory structures and essential oils of this genus up to the present time. Glandular trichomes, still insufficiently studied, present morphological peculiarities that differentiate this genus within the family: they are of two categories: capitate (with a wide distribution in this genus) and dendroid. The peltate trichomes, characteristic of many species of this family, are absent. The essential oils from the species of the genus Phlomis have been much more widely studied than the secretory structures. They show considerable variability depending on the species and the environmental conditions.

Review of Studies on Phlomis and Eremostachys Species (Lamiaceae) with Emphasis on Iridoids, Phenylethanoid Glycosides, and Essential Oils

As the sixth-largest Angiosperm family, Lamiaceae contains more than 245 genera and 7886 species that are distributed worldwide. It is also the third-largest family based on the number of taxa in Turkey where it is represented by 46 genera and 782 taxa with a high endemism ratio (44%). Besides, Lamiaceae are rich in plants with economic and medicinal value containing volatile and nonvolatile compounds. Many aromatic plants of Lamiaceae such as Salvia, Sideritis, Stachys, Phlomis, and Teucrium species are used in traditional herbal medicine throughout Turkey as well as in other Mediterranean countries. Salvia (Sage tea "Adaçayı"), Sideritis (Mountain tea "Dağçayı"), Stachys (Hairy Tea "Tüylü Çay"), and Phlomis (Turkish sage "Çalba or Şalba") are the largest genera that are used as herbal teas. This review focuses on the volatile and nonvolatile compounds of Lamiaceae from the genera Phlomis and Eremostachys of the subfamily Lamioideae with emphasis on iridoids, phenylethanoid glycosides, and essential oils.

Chemical profiling, antiviral and antiproliferative activities of the essential oil of Phlomis aurea Decne grown in Egypt

Here, we investigated the chemical composition of the edible Phlomis aurea oil and its anticancer potential on three human cancer cell lines, as well as its antiviral activity against Herpes simplex-1 (HSV-1). Exploring Phlomis aurea Decne essential oil by gas chromatography coupled with mass spectrometry (GC/MS) revealed the presence of four major components: germacrene D (51.56%), trans-β-farnesene (11.36%), α-pinene (22.96%) & limonene (6.26%). An antiproliferative effect, as determined by the MTT assay, against human hepatic, breast and colon cancer cell lines, manifested IC₅₀ values of 10.14, 328.02, & 628.43 μg mL^-1, respectively. Cytotoxicity assay of the Phlomis oil against Vero cell lines revealed a safe profile within the range of 50 μg ml^-1. Phlomis essential oil induced the apoptosis of HepG2 cells through increasing cell accumulation in sub G1 & G2/M phases, decreasing both S & G0/G1 phases of the cell cycle, triggering both caspases-3 &-9, and inhibiting cyclin dependent kinase-2 (CDK2). The antiviral activity of the oil against HSV-1 was investigated using the plaque reduction assay, which showed 80% of virus inhibition. Moreover, the molecular docking in silico study of the four major chemical constituents of the oil at the CDK2 binding site demonstrated marked interactions with the ATP-binding site residues through alkyl & Pi-alkyl interactions. Cell cycle distribution of HepG2 cells was studied using flow cytometry to highlight the apoptotic mechanistic approaches by measuring caspases-3 &-9 and CDK2 activities. Thus, the edible Phlomis oil can be regarded as a candidate for in vivo studies to prove that it is a promising natural antiviral/anticancer agent.

Chromatographic analysis, antimicrobial and insecticidal activities of the essential oil of Phlomis floccosa D. Don

The present study was conducted to investigate for the first time the chemical composition and insecticidal and antimicrobial properties of Phlomis floccosa D. Don. essential oil isolated by hydro-distillation of its aerial parts. Qualitative and quantitative analyses of the essential oil on the basis of gas chromatography and mass spectrometry (GC/FID and GC/MS) revealed the presence of 59 organic volatiles representing 86.9% of the total constituents. The major compounds were germacrene-D (19.7%) followed by β-caryophyllene (15.5%), caryophyllene oxide (8.3%), hexadecenoic acid (7.9%) and carvacrol (6.1%). The broth microdilution method was conducted to test the antimicrobial activity of the essential oil against five pathogens: Escherichia coli, Pseudomonas aeruginosa, Salmonella enterica, Staphylococcus aureus, Bacillus subtilis and the yeast Candida albicans. The oil of P. floccosa D. Don. shows promising activity against the Gram-positive bacteria S. aureus and B. subtilis and the yeast C. albicans (minimum inhibitory concentration = 625 μg.mL^-1 ). The effectiveness of the essential oil was assessed on both Tribolium confusum and Sitophilus zeamais pest insects and it was more pronounced against T. confusum, showing a moderate mortality of 47.5%.

Chemical composition, antioxidant, and enzyme inhibitory activities of the essential oils of three Phlomis species as well as their fatty acid compositions

This study aimed to investigate the chemical composition, antioxidant, and enzyme inhibitory activities of the essential oils of Phlomis armeniaca WILLD., P. nissolii L., and P. pungens WILLD. var. pungens as well as their fatty acid contents. Germacrene D was found as the major compound in the oils (24.7, 15.1, and 7.2%, respectively). Additionally, n-hexadecanoic acid, hexahydrofarnesyl acetone, β-caryophyllene, and linalool were the other main compounds in the oils. Among the fatty acids, C18:3 ω3 and C18:2 ω6 were determined in high quantities in P. armeniaca (23.14 and 18.01%, respectively) and P. pungens var. pungens (24.64 and 17.51%, respectively). The essential oils of P. armeniaca and P. pungens var. pungens showed remarkable antioxidant and metal chelating activities as well as great reducing power potentials. These oils also showed a moderate scavenging effect on ABTS radicals. The oils also exhibited various degrees of inhibitory activities on AChE, BChE, α-amylase, α-glucosidase, and tyrosinase.

GC/MS Evaluation and In Vitro Antioxidant Activity of Essential Oil and Solvent Extracts of an Endemic Plant Used as Folk Remedy in Turkey: Phlomis bourgaei Boiss

This study was outlined to examine the chemical composition of hydrodistilled essential oil and in vitro antioxidant potentials of the essential oil and different solvent extracts of endemic Phlomis bourgaei Boiss. used as folk remedy in Turkey. The chemical composition of the oil was analyzed by GC and GC-MS, and the predominant components in the oil were found to be β-caryophyllene (37.37%), (Z)-β-farnesene (15.88%), and germacrene D (10.97%). Antioxidant potentials of the solvent extracts and the oil were determined by four testing systems including β-carotene/linoleic acid, DPPH, reducing power, and chelating effect. In β-carotene/linoleic acid assay, all extracts showed the inhibition of more than 50% at all concentrations. In DPPH, chelating effect, and reducing power test systems, the water extract with 88.68%, 77.45%, and 1.857 (absorbance at 700 nm), respectively, exhibited more excellent activity potential than other extracts (hexane, ethyl acetate and methanol) and the essential oil at 1.0 mg/mL concentration. The amount of the total phenolics and flavonoids was the highest in this extract (139.50 ± 3.98 μg gallic acid equivalents (GAEs)/mg extract and 22.71 ± 0.05 μg quercetin equivalents (QEs)/mg extract).

Phytochemistry and biological activities of Phlomis species

The genus Phlomis L. belongs to the Lamiaceae family and encompasses 100 species native to Turkey, North Africa, Europe and Asia. It is a popular herbal tea enjoyed for its taste and aroma. Phlomis species are used to treat various conditions such as diabetes, gastric ulcer, hemorrhoids, inflammation, and wounds. This review aims to summarize recent research on the phytochemistry and pharmacological properties of the genus Phlomis, with particular emphasis on its ethnobotanical uses. The essential oil of Phomis is composed of four chemotypes dominated by monoterpenes (alpha-pinene, limonene and linalool), sesquiterpenes (germacrene D and beta-caryophyllene), aliphalic compounds (9,12,15-octadecatrienoic acid methyl ester), fatty acids (hexadecanoic acid) and other components (trans-phytol, 9,12,15-octadecatrien-1-ol). Flavonoids, iridoids and phenylethyl alcohol constitute the main compounds isolated from Phlomis extracts. The pharmacological activities of some Phlomis species have been investigated. They are described according to antidiabetic, antinociceptive, antiulcerogenic, protection of the vascular system, anti-inflammatory, antiallergic, anticancer, antimicrobial and antioxidant properties.