Volatile composition of ItalianThymus capitatus(L.) Hoffmanns. et Link leaves

Phytochemical Composition, Antioxidant and Antifungal Activity of Thymus capitatus, a Medicinal Plant Collected from Northern Morocco

Thymus capitatus is a Mediterranean endemic plant commonly known as "Zaïtra" in northern Morocco. As T. capitatus is widely used in traditional medicine and food, this present work aims to investigate the chemical compositions and biological activities of the T. capitatus leaves essential oil (TcLEO), acetonic (TcLAE), and methanolic extract (TcLME). The spectrophotometric determination demonstrated that T. capitatus is a natural source rich in phenolic contents (TPC) and flavonoid contents (TFC) and that TcLME revealed the highest TPC and TFC than TcLAE and TcLEO. The LC-MS analysis of phenolic compounds showed that paraben acid was predominant in both TcLME and TcLAE, followed by cinnamic acid and p-hydroxybenzoic acid. GC-MS analysis of the TcLEO revealed the presence of a total of 10 compounds, which were predominated by carvacrol. The antioxidant activity by ORAC was observed to be significantly higher in TcLEO and TcLAE than in TcLME. All samples used to assess DNA degradation effectively prevented DNA oxidation and, at the same time, had a prooxidant effect. The genotoxicity test showed that the T. capitatus were devoid of any mutagenic activity. Concerning antifungal activity, all samples were able to inhibit the growth of all microorganisms tested at low concentrations. TcLAE showed higher activity than TcLME, and in general, dermatophytes were more susceptible, being Microsporum canis the most sensitive one. Overall, the results obtained from this study confirm the wide uses of T. capitatus. Furthermore, the finding results suggest that the T. capitatus essential oil and extracts can be highly useful for pharmaceutical industries.

Health beneficial and pharmacological properties of p-cymene

p-cymene also known as p-cymol or p-isopropyltoluene is an alkyl-substituted aromatic compound naturally occurring in essential oils (EOs) of various aromatic plants, including the genus of Artemisia, Protium, Origanum, and Thymus. It is related to the family of terpenes, especially monocyclic monoterpenes. p-cymene is also present in several food-based plants such as carrots, orange juice, grapefruit, tangerine, raspberries and several spices. Numerous studies have demonstrated the pharmacological properties of the monoterpenes p-cymene, including antioxidant, anti-inflammatory, antiparasitic, antidiabetic, antiviral, antitumor, antibacterial, and antifungal activities. The p-cymene has also been reported to act as an analgesic, antinociceptive, immunomodulatory, vasorelaxant and neuroprotective agent. Its anticancer effects are related to some mechanisms such as the inhibition of apoptosis and cell cycle arrest. In this review, we critically highlighted the in vitro and in vivo pharmacological properties of the p-cymene molecule, providing insight into its mechanisms of action and potential applications in drug discovery. In light of this finding, in-depth in vivo studies are strongly required to validate the safety and beneficial effects of the p-cymene molecule in human healthcare and industrial applications as a potential source of drug discovery.

Ecological and Plant Community Implication on Essential Oils Composition in Useful Wild Officinal Species: A Pilot Case Study in Apulia (Italy)

The study focused on the effects of ecology (plant communities and topographical data) on composition of essential oils (EOs) of some officinal wild plant species (Lamiales): Clinopodium suaveolens, Salvia fruticosa subsp. thomasii, Satureja montana subsp. montana, and Thymbra capitata, in different environments of Apulia (Italy). C. suaveolens and S. fruticosa subsp. thomasii are rare species of conservation interest, while S. montana subsp. montana and T. capitata, have a wide distribution and are used in traditional medicine or as spices. Results showed that the ecological context (phytosociological and ecological features) may influence the composition of EOs of the studied species. High differences in the compound composition have been found in S. montana subsp. montana, whereas minor effects were observed in C. suaveolens, S. fruticosa subsp. thomasii, and T. capitata accessions. The understanding of such aspects is necessary for providing optimal conditions to produce EOs rich in compounds known for their biological activities. The results are of great interest also for EOs producers and at the same time to improve our knowledge and valorize wild officinal plants.

Ethnomedicinal use, phytochemistry, pharmacology, and food benefits of Thymus capitatus

ETHNOPHARMACOLOGICAL RELEVANCE

Thymus capitatusHoffm. et Link. is an endemic medicinal plant to the Mediterranean region. It is used in folk medicine to treat various diseases including diabetes, flu, cough, flatulence, dermatitis, indigestion, respiratory disorders, asthma, rheumatic, diarrhea, and influenza. It is also used as antiseptic, analgesic, stimulant, and sedative.

AIM OF THE REVIEW

In this review, previous reports on T. capitatusconcerningits taxonomy, botanical description, geographical distribution, ethnomedicinal use, phytochemistry, pharmacological properties, and food benefits were critically summarized.

MATERIALS AND METHODS

Scientificsearch engines including PubMed, ScienceDirect, SpringerLink, Web of Science, Scopus, Wiley Online, Scifnder, and Google Scholar were consulted to gather data on T. capitatus. The data presented in this work summarize T. capitatus phytochemical compounds, ethnomedicinaluses, pharmacological properties, and food value.

RESULTS

In traditional medicine, T. capitatusis used to treat various illnesses including diabetes, dermatitis, and diarrhea. The essential oils and extracts of T. capitatus exhibited several biological properties such as antibacterial, antioxidant, antifungal, antiparasitic, hypoglycemic, anticancer, antiviral, and hepatoprotective effects. T. capitatus possesses high nutritional value and its essential oil showed promising activity in food preservation. Phytochemical characterization of T. capitatus revealed the presence of several classes of secondary metabolites such as terpenoids, flavonoids, and phenolic acids.

CONCLUSIONS

Ethnomedicinal surveys indicated the use of T. capitatus for the treatment of various disorders. Pharmacological reports showed that T. capitatus especially its essential oils, exhibited potent antimicrobial, antioxidant, antidiabetic and hepatoprotective effects. These findings confirmed the link between traditional medicinal use and scientific biological results. Moreover, T. capitatus exhibited a potent food preservative effect which justifies its use in traditional medicine as a food additive. In light of these findings, further studies to validate the industrial applications of T. capitatus essential oils as a food additive are required. Further investigations on the in vivo pharmacological properties of T. capitatus are strongly recommended to validate the results of its clinical uses as an antimicrobial, hepatoprotective, and antiviral agent. Toxicological tests and pharmacokinetic investigations are also needed to validate the safety and efficacy ofT. capitatus and its bioactive compounds.

Plant Volatilome in Greece: a Review on the Properties, Prospects, and Chemogeography

Knowing plant volatile chemodiversity and its distribution is essential in order to study biological processes, to estimate the plants' value in use, and to establish sustainable exploitation practices. Yet, attempts to collect and assess data on scent diversity and properties in well-defined geographical areas are rare. Here, we developed a geo-referenced database of the plant volatilome in Greece by consolidating the results included in 116 research articles published in the last 25 years. The data set compiled includes 999 volatile organic compounds distributed into 178 plant taxa, 59 genera, and 19 families. Distillation is the acquisition method almost exclusively used, whereas headspace techniques that would allow the study of subtle ecological processes are generally lacking. Sesquiterpenes show the greatest richness of compounds, followed by monoterpenes and aliphatics. We assess the volatility of the compounds using the normal boiling point (nBP) as its reverse indicator, and we present the volatility spectra of the blends of the genera studied. Mean nBPs vary among genera, with maximal differences as wide as 118.4°. Finally, we feature basic chemodiversity maps for three aromatic plants, and discuss their importance and prospects as a special case of natural resources maps.

Characterization of aroma-active and phenolic profiles of wild thyme (Thymus serpyllum) by GC-MS-Olfactometry and LC-ESI-MS/MS

The present study was designed to characterize the volatile, aroma-active and phenolic compounds of wild thyme. Volatile components of T. serpyllum were extracted by use of the purge and trap technique with dichloromethane and analyzed by gas chromatography-mass spectrometry (GC-MS). The extraction method gave highly representative aromatic extract of the studied sample based on the sensory analysis. A total of 24 compounds were identified and quantified in Thymus serpyllum. Terpenes were qualitatively and quantitatively the most dominant volatiles in the sample. Aroma extract dilution analysis (AEDA) was used for the first time for the determination of aroma-active compounds of Thymus serpyllum. In total, 12 aroma-active compounds were detected in the aromatic extract by GC-MS-Olfactometry and terpenes were the most abundant compounds. High-performance liquid chromatography/electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) method was used for the phenolic compounds analysis. 18 phenolic compounds were identified and quantified in the T. serpyllum. Luteolin 7-O-glucoside, luteolin and rosmarinic acid were the most abundant phenolics in this herb.