Nutritional and Physiological Properties of Thymbra spicata: In Vitro Study Using Fecal Fermentation and Intestinal Integrity Models.

(Poly)phenolic-rich Mediterranean plants such as Thymbra spicata have been associated with several health-promoting effects. The nutritional value, as well as physiological interaction of T. spicata with the gastrointestinal tract, has not been investigated before. The nutritional composition of T. spicata leaves was here characterized by standard analytical methods. T. spicata leaves were subjected to ethanolic extraction, simulated gastrointestinal digestion, and anaerobic microbial gut fermentation. Phenols/flavonoid contents and radical scavenging activity were assessed by colorimetric methods. The volatile organic compounds (VOCs) were detected by gas chromatography coupled with mass spectrometry. The effect on intestinal integrity was evaluated using a Caco-2 monolayers mounted in a Ussing chamber. T. spicata contains a high amount of fiber (12.3%) and unsaturated fatty acids (76% of total fat). A positive change in VOCs including short-chain fatty acids was observed without significant change in viable microbe. T. spicata and carvacrol (main phenolic compound) enhanced ionic currents in a concentration-dependent manner without compromising the Caco-2 monolayer's integrity. These effects were partially lost upon simulated digestion and completely abolished after colonic fermentation in line with polyphenols and carvacrol content. Conclusion: T. spicata represents a promising nutrient for the modulation of gut microbiota and the gut barrier. Further studies must better define its mechanisms of action.

Unusual immunosuppressive pyridine-containing bisnor- (c23), tetranor- (c21) and pentanor- (c20) sesterterpenoids from Tibetan Leucosceptrum canum.

An unusual pyridine-containing sesterterpenoid, leucosceptrodine (1), and five new nor-leucosceptrane sesterterpenoids, including bisnor- (C23, 2), tetranor- (C21, 3) and pentanor- (C20, 4-6) skeletons, were isolated from the leaves of Tibetan Leucosceptrum canum. Their structures including their absolute configurations were determined by extensive spectroscopic analyses and quantum chemical calculations. A single crystal of one epimer (5) was crystallized from a pair of inseparable epimers, and its structure including its absolute configuration was determined by X-ray crystallographic analysis. The immunosuppressive activities of compounds 1-4 with different potencies were evaluated by inhibiting the secretion of cytokines TNF-α and IL-6 in LPS-induced RAW264.7 macrophages.

Optimization of Ziziphora clinopodioides L. essential oil nanoencapsulation in chitosan nanocomplex by response surface methodology.

Nano-encapsulation of essential oils, a specific area of interest, can help overcome challenges associated with their commercial use. This study aimed to evaluate the effect of different concentrations of chitosan, Ziziphora clinopodioides L. essential oil (ZcEO), and Sodium-Tri Polyphosphate (TPP), both individually and in interaction, on several properties of EO-loaded chitosan nanoparticles. These properties include particle size (PS), zeta potential (ZP), and encapsulation efficiency (EE) using a two-stage emulsion-ionic gelation approach. The optimization of the parameters was done by response surface methodology using Box-Behnken design. The chemical composition of ZcEO was analyzed as well. The primary compounds in ZcEO were found to be pulegone (29.24 %), 1,3-dimethyl-2-(2-methylpropylidene) imidazolidine (9.05 %), piperitenone (6.65 %), thymol (5.38 %), and carvacrol (5.27 %). The PS ranged from 117.33 to 4934.1 nm, the ZP varied from -1.1 to -30.83 mV, and the EE spanned from 31.74 to 87.04 %. The results showed that an increase in the initial EO content led to a decrease in PS and ZP, but an increase in EE. Moreover, increasing the TPP concentration resulted in an enhancement in PS, ZP, and EE, whereas increasing the Chs concentration led to a slight increase in PS, ZP, and EE. Furthermore, the results of this study proved the interaction effect of different parameters on the responses investigated. Under optimized conditions, the optimal concentrations of chitosan, ZcEO and TPP were attained at 6.768, 6.078, and 7.595 mg/mL respectively. This resulted in a PS of 117.331 nm, a ZP of -20.949 mV, and an EE of 75.385 %. In conclusion, the results suggest that adjusting the concentrations of Chs, EO, and TPP is an effective approach to controlling the properties of NPs and optimizing their performance.

A multidimensional strategy for characterization, distinction, and quality control of two Clinopodium medicinal plants.

ETHNOPHARMACOLOGICAL RELEVANCE: Clinopodium chinense Kuntze (CC) and Clinopodium polycephalum (Vaniot) C. Y. Wu & S. J. Hsuan (CP) are both included in the Pharmacopoeia of the People's Republic of China (edition 2020) as the legitimate source of "Duan Xue Liu" (DXL), which is a crucial traditional Chinese medicine used as a clinical remedy for bleeding diseases. However, the differences in plant endogenous metabolites and bioactivities between CC and CP are still unclear. AIM OF THE STUDY: This study aims to provide a scientific basis to investigate the differences between CC and CP ensuring the efficient and safe use of DXL. MATERIALS AND METHODS: A multidimensional strategy including plant metabolomics, digital reference standard (DRS) analyzer, and biological activities assay was creatively constructed for the characterization, distinction, and quality control of CC and CP. RESULTS: There were apparent differences in the metabolites between CC and CP. 7 compounds contributing to the differences were successfully identified. On that basis, linear calibration using two reference substances (LCTRS) methods was proved as a more accurate and specific quality analysis method for CC and CP. In addition, bioactivity assays showed that both CC and CP exhibited obvious hemostatic activity, while CC showed greater potential to resist inflammation and free radicals. CONCLUSION: In summary, it was the first time to investigate the chemical constituents and bioactivities differences between CC and CP with the help of plant metabolomics, DRS study, and biological activity assays. These two plants were significantly separated in the integrated analysis, suggesting that we should pay attention to the distinction to prevent unexpected risks caused by medicinal materials.

Generation, degradation mechanism, and toxicity evaluation of pigmented compounds in Leucosceptrum canum nectar.

Leucosceptrum canum nectar (LCN) emerges as a novel food resource, distinguished by its unique dark brown hue. This study delves into the composition and toxicity assessment of novel pigments within LCN. Through liquid chromatography-tandem mass spectrometry (LC-MS/MS) and chemical synthesis, seventeen 2,5-di-(N-(-)-prolyl)-para-benzoquinone (DPBQ) analogs in LCN were identified. These compounds are synthesized in LCN via the Michael addition reaction, utilizing p-benzoquinone (BQ), derived from phenol metabolism, and amino acids as substrates in an alkaline environment (pH = 8.47 ± 0.06) facilitated by dissolved ammonia and the presence of alkaloids. Analytical techniques, including principal component analysis (PCA), orthogonal partial least squares discrimination analysis (OPLS-DA), and volcano plot analysis, were employed to investigate DPBQ analog degradation within the nectar and honey's unique environments. Toxicity assays revealed that DPBQ analogs exhibited no toxicity, displaying a significant difference in toxicity compared to the precursor compound BQ at concentrations exceeding 25 µM.

Preparation technologies, structural features, and biological activities of polysaccharides from Mesona chinensis Benth.: A review.

ETHNOPHARMACOLOGICAL RELEVANCE: Mesona chinensis Benth. (or Platostoma palustre (Blume) A. J. Paton) is an important medicinal and edible plant also known as the Hsian-tsao in China and Southeast Asian countries. It is cold in nature and sweet in taste, with the effects of clearing heat, relieving heatstroke and diuretic, and traditionally used to treat heatstroke, erysipelas, hypertension, joint pain and other diseases in folk medicine. It is also a popular supplement with the function of detoxifying and heat-clearing use in Asia. It is used to be processed into the popular tea, Bean jelly, and so on. Published studies have demonstrated that polysaccharides from M. chinensis (MCPs) are one of the principal bioactive ingredients with a variety of health-promoting effects in the prevention and treatment of diseases, including antioxidant, immunomodulation, anti-inflammatory, hepatoprotective, anti-tumor, hypoglycemic, regulation of gut microbiota, and other pharmacological properties. AIM OF THE REVIEW: This review aims to compile the extraction and purification methods, structural characteristics, pharmacological activities including the mechanism of action of MCPs, and to further understand the applications of M. chinensis in order to lay the foundation for the development of MCPs. MATERIALS AND METHODS: By inputting the search term "Mesona chinensis polysaccharides", relevant research information was obtained from databases such as PubMed, Google Scholar, Web of Science, and China National Knowledge Infrastructure (CNKI). RESULTS: More than 40 polysaccharides have been extracted from M. chinensis, different extraction and purification methods have been described, as well as the structural features and pharmacological activities of MCPs have been systematically reviewed. Polysaccharides, as important components of M. chinensis, were mainly extracted by methods such as hot water dipping method, hot alkali extraction method, enzyme-assisted extraction method and ultrasonic-assisted extraction method, subsequently obtained by decolorization, deproteinization, removal of other small molecules and separation on various chromatographic columns. The chemical composition and structure of MCPs show diversity and have a variety of pharmacological activities, including antioxidant, immunomodulation, anti-inflammatory, hepatoprotective, anti-tumor, hypoglycemic, regulation of gut microbiota, and so on. CONCLUSIONS: This article systematically reviews the research progress of MCPs in terms of extraction and purification, structural characteristics, rheological gel properties, pharmacological properties, and safety assessment. The potentials and roles of M. chinensis in the field of medicine, functional food, and materials are further highlighted to provide references and bases for the high-value processing and utilization of MCPs.

Effects of three different polysaccharides on the sol gel-behavior, rheological, and structural properties of tapioca starch.

The sol-gel behavior of tapioca starch (TS) plays a crucial role in the processing and quality control of flour-based products. However, natural tapioca starch has low gel strength and poor viscosity, which tremendously limits its application. To solve this problem, this study investigated the effects of κ-carrageenan (KC), konjac gum (KGM), and Mesona chinensis Benth polysaccharide (MCP) on the pasting behavior, rheological, and structural properties of tapioca starch. KC, KGM, and MCP significantly increased the viscosity of TS. With the exception of high-concentration KGM (0.5 %), all other blending systems showed decrease in setback. This may be attributed to the stronger effect of the high-concentration KC (0.5 %) and MCP (0.5 %) functional groups interacting with starch. KC, KGM, and MCP effectively improved the dynamic modulus (G' and G") of TS gel and were effective in increasing the gel strength and hardness of TS. The FT-IR analysis indicated that the short-range order of TS was mainly influenced by polysaccharides through non-covalent bonding interactions. Furthermore, it was confirmed that three polysaccharides could form dense structures by hydrogen bonding with TS. Similarly, more stable structure and pore size were observed in the microstructure diagram.

Undescribed compounds from Clinopodium chinense (Benth.) O. Kuntze and their coagulation activity studies.

Four rare compounds (1-4), including one 1,4-epoxy-benzoxepane derivative and one ringed prenylated naphthoquinoid skeleton, as well as one isopimarane-type diterpenoid and one megastigmane-type glycoside, along with three known megastigmane-type glycosides (5-7) were isolated from the ethanol extracts of C. chinense. Their structures were determined on the basis of 1D, 2D NMR, HR-ESI-MS and DP4+ analysis. Meanwhile, the in vitro evaluation indicated that compound 2 and 6 exhibited excellent procoagulant activities, which can significantly shorten prothrombin time (PT) and activated partial thromboplastin time (APTT), respectively.

Phytochemical analysis of Clinopodium candidissimum (Munby) Kuntze growing in Algeria by an integrated HS-SPME-GC-MS, NMR and HPLC-DAD-MSn approach: valorisation of an endemic natural source of bioactive compounds.

Clinopodium candidissimum (Munby) Kuntze (Lamiaceae) is used in traditional medicine and as a food condiment in Algeria, where it is known as Zaater cheleuh and Nabta elbida. Here, we report the comprehensive characterisation of non-volatile polar constituents extracted from C. candidissimum aerial parts (a mixture of inflorescences, stems and leaves), and their aroma profile. Qualitative 1H-NMR and quali-quantitative HPLC-MSn analyses of fractions obtained with solvents at different polarity revealed the presence of aglyconic and glycosylated flavonoids (3.1%), phenylpropanoids (3.6%), gallic acid derivatives (0.76%), and triterpenoids (0.62%), among the others. On the other hand, HS-SPME-GC-MS allowed to identify 38 volatile constituents, among which the oxygenated monoterpenes pulegone (44.8%), piperitenone (6.6%), isopulegone (5.8%) and neo-menthol (3.8%), and the sesquiterpene hydrocarbons germacrene D (16.2%) and bicyclogermacrene (3.0%) were the most abundant. Overall, results indicate that C. candidissimum represents an endemic natural source of antioxidants and bioactive compounds, and they will be useful for further studies on this species.

Diverse terpenoid glycosides with in vitro cytotoxicity from Glechoma longituba.

Terpenoids are the largest class of all known natural products, possessing structural diversity and numerous biological activities. Ten previously undescribed terpenoid glycosides, glechlongsides A-J (1-10), were isolated from the ethanol extract of the whole plant of Glechoma longituba, including diterpenoid glycoside and pentacyclic triterpenoid saponin. The structures of these compounds were characterized by extensive analysis of 1D and 2D NMR as well as HRESIMS spectra. In addition, glechlongsides F-I (6-9) exhibited weak cytotoxicity against human cancer cell lines BGC-823, Be1, HCT-8, A2780, and A549 with IC50 values ranging from 3.77 to 30.95 µM, respectively.

Abietane diterpenoids and iridoids from Caryopteris mongolica.

Six new abietane diterpenoids (1-6) and five undescribed iridoids (7-11) have been isolated from the aerial parts of Caryopteris mongolica. The intricate structural characterization of these compounds was meticulously undertaken using an array of advanced spectroscopic techniques. This process was further enhanced by the application of DP4+ probability analyses and electronic circular dichroism (ECD) calculations. Following isolation and structural elucidation, the cytotoxicity of these compounds was evaluated. Among them, compound 3 stood out, displaying significant cytotoxic activity against HeLa cells with an IC50 value of 7.83 ± 1.28 µmol·L-1. Additionally, compounds 1, 2, 4, 9, and 10 manifested moderate cytotoxic effects on specific cell lines, with IC50 values ranging from 11.7 to 20.9 µmol·L-1.

Phenylboronic Acid and Amino Bifunctional Modified Adsorbent for Quickly Separating Phenolic Acids from Crude Extract of Clerodendranthus spicatus and Evaluation of Their Antioxidant and Hypoglycemic Activities.

A novel phenylboronic acid and amino bifunctional modified silica gel (SiO2-NH2-FPBA) was prepared, which was 30-80 µm, had a pore size of 8.69 nm, a specific surface area of 206.89 m2/g, was stable at low temperature, and contained 0.4793 mmol/g of the phenylboronic acid group and 1.6377 mmol/g of the amino group. It was used to develop a rapid separation method for phenolic acids. The results showed that it could adsorb 93.64 mg/g caffeic acid, 89.35 mg/g protocatechuic acid and 79.66 mg/g gallic acid. The adsorption process was consistent with the pseudo-second-order model (R2 > 0.99), and fitted the Langmuir isotherm model well (R2 > 0.99). CH3COOH could effectively desorb phenolic acids (>90%) and did not destroy their structures. When SiO2-NH2-FPBA was added to crude extract of Clerodendranthus spicatus, 93.24% of the phenolic acids could be captured, and twenty-two kinds of phenolic acids were identified by Q Exactive HF LC-MS. Furthermore, the isolated phenolic acids from Clerodendranthus spicatus possessed great DPPH, ABTS, and hydroxyl radicals scavenging activities and ferric reducing power. They also demonstrated effective inhibition of α-amylase and α-glucosidase activities (IC50 = 110.63 ± 3.67 µg/mL and 64.76 ± 0.30 µg/mL, respectively). The findings indicate that SiO2-NH2-FPBA has significant potential in practical applications of separating active constituents from natural resources.

Discovery of Unusual Sesterterpenoids from Colquhounia coccinea var. mollis and Their Metabolic Implications.

Three unusual sesterterpenoids featuring unprecedented rearranged colquhounane (C25) and tetranorcolquhounane (C21) frameworks, colquhounoids E (1) and F (3) and norcolquhounoid F (2), were isolated from a Lamiaceae medicinal plant Colquhounia coccinea var. mollis. Their structures were elucidated by spectroscopic analysis and quantum chemical calculations. A biomimetic inspired regioselective cyclopropane cleavage was achieved under acidic conditions. The immunosuppressive activities of these new sesterterpenoids were also evaluated.

Screening of 20 species from Lamiaceae family based on phytochemical analysis, antioxidant activity and HPLC profiling.

The Lamiaceae family encompasses numerous species highly valued for their applications in medicine, food, and cosmetics. In order to screen the Lamiaceae family and discover new sources of phytochemicals and antioxidants, we comprehensively evaluated 20 species from this family, including Phlomis herba-venti, P. tuberosa, P. olivieri, P. kurdica, Nepeta sp., N. cataria, N. saccharata, Stachys sp., S. inflata, Scutellaria albida, Marrubium parviflora, Mentha pulegium, Thymus kotschyanus, Lamium album, Salvia officinalis, S. multicaulis, S. macrochlamys, S. candidissima, S. verticillata, and S. nemorosa. The aerial parts of these species were analyzed to determine their total phenolic (TPC) and flavonoid (TFC) contents, total tannin content (TTC), ascorbic acid content (AAC), antioxidant capacity (assessed by FRAP and DPPH assays), and polyphenolic components (by HPLC). The phytochemical compounds and antioxidant properties varied widely among different species. The highest concentrations of TPC (70.93 mg GAE/g DW), TFC (17.89 mg Que/g DW), TTC (6.49 mg TAE/100 g), and AAC (1.15 mg AA/g DW), as well as the greatest antioxidant activity, were observed in different Salvia species. Additionally, chlorogenic and rosmarinic acids were the primary phenolic compounds identified in the extracts from the investigated Lamiaceae family. According to Hierarchical Cluster Analysis (HCA) and Principal Component Analysis (PCA), three groups of species were identified, characterized by variations in phytochemical composition and antioxidant capacity. The results obtained can provide new natural sources of phytochemicals and antioxidant agents, particularly from Salvia species, for the advancement of new products in the food, agricultural, cosmetics and health industries.

Development of biomaterials based on chitosan-gelatin nanofibers encapsulated with Ziziphora clinopodioides essential oil and Heracleum persicum extract for extending the shelf-life of vacuum-cooked beef sausages.

The aims of the current study were to encapsulate Ziziphora clinopodioides essential oil (ZEO, 0%, 0.15%, and 0.25%) and Heracleum persicum extract (HPE, 0%, 0.25%, and 0.5%) into the chitosan-gelatin (CH-GE) nanofibers through the electrospinning process to improve the shelf-life of vacuum-cooked beef sausages through 70 days of refrigerated storage. Scanning electron microscopy indicated that all nanofibers appeared thin, well-defined, smooth, and possessed uniform thread-like fibers without any beads or nodule formations. The Fourier transform infrared spectroscopy study confirmed the molecular interaction between encapsulated compounds and CH-GE nanofibers. The X-ray diffraction analysis of nanofibers showed an increase in crystallinity after incorporating ZEO and HPE into the polymer. Treated sausages with CH-GE-ZEO 0.25%-HPE 0.25% and CH-GE-ZEO 0.25%-HPE 0.5% showed significantly lower microbial population and lipid oxidation than the control group during the experiment period (P < 0.05). Sausages formulated with designated CH-GE nanofibers had better microbial, chemical, and sensory properties compared to sausages treated with pure ZEO/HPE during refrigerated storage. The findings also showed that treated sausages with CH-GE-ZEO 0.25%-HPE 0.5% had the highest color, odor, texture, and overall acceptability after 70 days of refrigerated storage conditions. Therefore, this treatment could be applicable for the prolonged storage conditions during cooked beef sausage production.

Labdane diterpenoids from Lagopsis supina and their anti-neuroinflammatory activity.

In this study, ten labdane-type diterpenoids 1-10 were isolated from a methanol extract of the whole plant Lagopsis supina, including three undescribed compounds 1-3. Their structures were determined by spectroscopic data analyses such as HR-ESI-MS, 1D, and 2D NMR, as well as comparison with literature data. At the same time, the absolute configuration of five compounds 2-5 and 10 was confirmed for the first time by the single crystal X-ray diffraction method. All the compounds were isolated from L. supina for the first time. The CCK-8 assay showed that all compounds had no significant damage to BV-2 microglial cells, and then screened their inhibitory effects of nitric oxide production stimulated by lipopolysaccharide in BV-2 microglial cells. The pharmacological results showed that compound 4 greatly inhibited LPS-stimulated NO release at the concentration of 10 µM, indicating that it has potential anti-neuroinflammatory activity.

Implications of the Cultivation of Rosemary and Thyme (Lamiaceae) in Plant Communities for the Development of Antioxidant Therapies.

Oxidative stress is the most critical factor in multiple functional disorders' development, and natural antioxidants could protect the human body against it. Our study aims to investigate the polyphenol content of four extracts of two medicinal plants (Rosmarinus officinalis L. and Thymus vulgaris L.) and analyze the correlation with their antioxidant activity. The research was carried out on extracts of rosemary and thyme obtained from species cultivated together in plant communities. Both were compared with extracts from species cultivated in individual crops (control crops). Their polyphenols were determined by spectrophotometric methods (dosage of flavones, phenol carboxylic acids, and total polyphenols) and chromatography (UHPLC-MS and FT-ICR MS). Triterpenic acids were also quantified, having a higher concentration in the thyme extract from the culture. The antioxidant activity of the dry extracts was evaluated in vitro (DPPH, ABTS, and FRAP) and in silico (prediction of interactions with BACH1/BACH2 transcription factors). The concentrations of polyphenols are higher in the extracts obtained from the sources collected from the common crops. These observations were also validated following the chromatographic analysis for some compounds. Statistically significant differences in the increase in the antioxidant effect were observed for the extracts from the common batches compared to those from the individual ones. Following the Pearson analysis, the IC50 values for each plant extract were strongly correlated with the concentration of active phytoconstituents. Molecular docking studies revealed that quercetin could bind to BTB domains of BACH1 and BACH2 transcription factors, likely translating into increased antioxidant enzyme expression. Future studies must validate the in silico findings and further investigate phytosociological cultivation's effects.

Phytochemical analysis for ten Peruvian Mentheae (Lamiaceae) by liquid chromatography associated with high resolution mass spectrometry.

The profile of secondary metabolites in ten members of tribe Mentheae (Nepetoideae, Lamiaceae) from Peru by liquid chromatography associated with high resolution mass spectrometry, is presented. Salvianolic acids and their precursors were found, particularly rosmarinic acid, caffeic acid ester derivatives, as well as a diversity of free and glycosylated flavonoids as main substances. At all, 111 structures were tentatively identified.

Screening of Volatile Compounds, Traditional and Modern Phytotherapy Approaches of Selected Non-Aromatic Medicinal Plants (Lamiaceae, Lamioideae) from Rtanj Mountain, Eastern Serbia.

Ironwort (Sideritis montana L.), mountain germander (Teucrium montanum L.), wall germander (Teucrium chamaedrys L.), and horehound (Marrubium peregrinum L.) are species widely distributed across Europe and are also found in North Africa and West Asia. Because of their wide distribution they express significant chemical diversity. For generations, these plants have been used as medical herbs for treating different aliments. The aim of this paper is to analyze volatile compounds of four selected species that belong to the subfamily Lamioideae, family Lamiaceae, and inspect scientifically proven biological activities and potential uses in modern phytotherapy in relation to traditional medicine. Therefore, in this research, we analyze the volatile compounds from this plants, obtained in laboratory by a Clevenger-type apparatus, followed by liquid-liquid extraction with hexane as the solvent. The identification of volatile compounds is conducted by GC-FID and GC-MS. Although these plants are poor in essential oil, the most abundant class of volatile components are mainly sesquiterpenes: germacrene D (22.6%) in ironwort, 7-epi-trans-sesquisabinene hydrate (15.8%) in mountain germander, germacrene D (31.8%) and trans-caryophyllene (19.7%) in wall germander, and trans-caryophyllene (32.4%) and trans-thujone (25.1%) in horehound. Furthermore, many studies show that, in addition to the essential oil, these plants contain phenols, flavonoids, diterpenes and diterpenoids, iridoids and their glycosides, coumarins, terpenes, and sterols, among other active compounds, which affect biological activities. The other goal of this study is to review the literature that describes the traditional use of these plants in folk medicine in regions where they grow spontaneously and compare them with scientifically confirmed activities. Therefore, a bibliographic search is conducted on Science Direct, PubMed, and Google Scholar to gather information related to the topic and recommend potential applications in modern phytotherapy. In conclusion, we can say that selected plants could be used as natural agents for promoting health, as a source of raw material in the food industry, and as supplements, as well as in the pharmaceutical industry for developing plant-based remedies for prevention and treatment of many diseases, especially cancer.

Chemical Composition, Antioxidant Properties, and Antibacterial Activity of Essential Oils of Satureja macrostema (Moc. and Sessé ex Benth.) Briq.

Satureja macrostema is a plant that is located in various regions of Mexico and is used in a traditional way against illness. Essential oils (EOs) were obtained from leaves Satureja macrostema and the chemical composition was evaluated by gas chromatography-mass spectrometry (GC-MS). The antioxidant effect of the oil was assayed by 2,2-diphenyl-1-picrylhydrazyl (DPPH) and by Trolox Equivalent Antioxidant Capacity (TEAC). In vitro antibacterial activity against Escherichia coli and Staphylococcus aureus was determined using a broth microdilution assay and thin layer chromatography-direct bioautography (TLC-DB) to identify active antibacterial compounds. The EOs analysis showed 21 compounds, 99% terpenes, and 96% oxygenated monoterpenes, with trans-piperitone epoxide (46%), cis-piperitone epoxide (22%), and piperitenone oxide (11%) as more abundant compounds. Likewise, S. macrostema EOs showed an antioxidant activity of DPPH = 82%, with 50% free radical scavenging (IC50) = 7 mg/mL and TEAC = 0.005, an antibacterial effect against E. coli of 73% inhibition, and 81% over S. aureus at dose of 100 µL of undiluted crude oil. The TLC-DB assay showed that the most active compounds were derived from piperitone. The comparison with other studies on S. macrostema shows variability in the compounds and their abundances, which can be attributed to climatic factors and the maturity of plants with similar antioxidant and antibacterial activities.