Costunosides A-C: cytotoxic sesquiterpene lactones from the rhizomes of Aucklandia costus Falc

Three new eudesmane type rare sesquiterpene lactone galactosides, costunosides A-C (1-3) were isolated from the rhizomes of Aucklandia costus along with ten known compounds (4-13). Costunosides A-C (1-3) are the first example of naturally eudesmane glycosides containing a β-galactopyranoside moiety. The structure and relative configurations of these compounds were established by comprehensive analysis of MS and, in particular 1D/2D NMR spectroscopic data. The isolated compounds were tested against a panel of human cancer cell lines, where compounds 3, 6 and 7 have shown promising cytotoxic activity against PC-3, HCT-116 and A549 cell lines with IC50 values in the range of 3.4 µM to 9.3 µM, respectively. Costunosides A-C (1-3) were also screened for inhibition assay of acetyl-cholinesterase (AChE), and butyrylcholinesterase (BChE) and found inactive at a concentration of 10 µM.

[A new allo-aromadendrane sesquiterpene from Dendrobium nobile]

To study the chemical constituents in the non-alkaloid part of stems of Dendrobium nobile. The macroporous adsorption resin, MCI, silica gel, RP-C_(18), and Sephadex LH-20 gel, preparative thin layer chromatography, and preparative high-performance liquid chromatography(HPLC) were used to isolate and purify the compounds. The structures of the compound were determined according to the spectra data, physicochemical properties, and relevant references. A total of 8 compounds were isolated from D. nobile, which were soltorvum F(1), p-hydroxyphenylpropionic acid(2), vanillic acid(3), p-hydroxybenzoic acid(4), N-trans-cinnamic acid acyl-p-hydroxybenzene ethylamine(5),(+)-(1R,2S,3R,4S,5R,6S,9R)-2,11,12-trihydroxypicrotoxane-3(15)-lactone(6), dendronobilin H(7), soltorvum E(8). Compound 1 was a novel compound, named as soltorvum F. Compound 8 was isolated from Dendrobium species for the first time.

Molecular and Functional Analyses of Characterized Sesquiterpene Synthases in Mushroom-Forming Fungi

Sesquiterpenes are a type of abundant natural product with widespread applications in several industries. They are biosynthesized by sesquiterpene synthases (STSs). As valuable and abundant biological resources, mushroom-forming fungi are rich in new sesquiterpenes and STSs, which remain largely unexploited. In the present study, we collected information on 172 STSs from mushroom-forming fungi with experimentally characterized products from the literature and sorted them to develop a dataset. Furthermore, we analyzed and discussed the phylogenetic tree, catalytic products, and conserved motifs of STSs. Phylogenetic analysis revealed that the STSs were clustered into four clades. Furthermore, their cyclization reaction mechanism was divided into four corresponding categories. This database was used to predict 12 putative STS genes from the edible fungi Flammulina velutipes. Finally, three FvSTSs were selected to experimentally characterize their functions. FvSTS03 predominantly produced Δ-cadinol and FvSTS08 synthesized β-barbatene as the main product; these findings were consistent with those of the functional prediction analysis. A product titer of 78.8 mg/L β-barbatene was achieved in Saccharomyces cerevisiae via metabolic engineering. Our study findings will help screen or design STSs from fungi with specific product profiles as functional elements for applications in synthetic biology.

Chemical composition and antimicrobial activity of essential oil from Popowia pisocarpa (Bl.) Endl., Walp. Repert. (Annonaceae)

The volatile compositions and antimicrobial activity of aerial parts of Popowia pisocarpa from Vietnam were reported for the first time. From the GC/MS spectral, spathulenol (35.9%), bicyclogermacrene (5.7%) and muurola-4,10(14)-dien-1β-ol (4.2%) among the sesquiterpenoids, along with 4,4-dimethyl-3-(3-methylbut-3-enylidene)-2-methylenebicyclo[4,1,0]heptane (17.7%), an unsaturated cyclic compound, were the main constituents of the essential oil. Monoterpenoids were not identified in the essential oil. The essential oil displayed antimicrobial activity against the Gram-negative Escherichia coli ATCC 25922 with MIC value of 16.0 µg/mL and IC50 value of 8.52 µg/mL. In addition, the essential oil also exhibited activity towards the Gram-positive bacteria of Staphylococcus aureus ATCC 13709, Bacillus subtilis ATCC 6633, and Lactobacillus fermentum N4 with MIC value of 64.0 µg/mL each and corresponding IC50 values of 11.06 µg/mL, 26.47 µg/mL and 15.68 µg/mL, respectively. The essential oil did not inhibit the growth of Pseudomonas aeruginosa ATCC 15442, Salmonella enterica and the yeast Candida albicans ATCC 10231.

Siparuna guianensis Essential Oil Antitumoral Activity on Ehrlich Model and Its Effect on Oxidative Stress

This work aims to evaluate the chemical composition, in vitro antioxidant capacity, and in vivo antitumoral activity of S. guianensis essential oil against Ehrlich's ascitic carcinoma and the effects on oxidative stress. The animals (Mus musculus) received a daily dose of S. guianensis oil orally (100 mg/kg) for 9 days. The main constituents of essential oil were curzerenone (16.4±1.5 %), drimenol (13.7±0.2 %), and spathulenol (12.4±0.8 %). S. guianensis oil showed antioxidant activity, inhibiting 11.1 % of DPPH radicals (95.7 mgTE/g); and 15.5 % of the β-carotene peroxidation. The group treated with S. guianensis showed a significant reduction in tumor cells (59.76±12.33) compared to the tumor group (96.88±19.15). Essential oil of S. guianensis decreased MDA levels and increased SOD levels in liver tissue. The essential oil of S. guianensis reduced oxidative stress, and showed antitumor and antioxidant activity, being characterized as a new chemical profile in the investigation of pathologies such as cancer.

A New Essential Oil from the Native Andean Species Nectandra laurel Klotzsch ex Nees of Southern Ecuador: Chemical and Enantioselective Analyses

The leaves of Nectandra laurel Klotzsch ex Nees, belonging to the family, Lauraceae, were collected in the province of Loja (Ecuador), dried, and analytically steam-distilled. An unprecedented essential oil was obtained, with a 0.03% yield by weight of dry plant material. The volatile fraction was submitted to qualitative (GC-MS) and quantitative (GC-FID) chemical analysis, on two orthogonal stationary phases. Seventy-eight compounds were detected and quantified on at least one column. The essential oil was dominated by sesquiterpene hydrocarbons (53.0-53.8% on the non-polar and polar stationary phase, respectively), followed by oxygenated sesquiterpenoids (18.9-19.0%). A third group was constituted by metabolites of other origins, mainly aliphatic compounds, apparently derived from the acetate pathway (11.7-8.5%). The major components of the EO (≥3.0% with at least one column) were δ-selinene (30.5-28.8%), δ-cadinene (5.4-6.4%), epi-α-cadinol (4.9-5.2%), an undetermined compound with a molecular weight of 204 (3.4-4.2%), α-pinene (3.3-2.9%), and α-cadinol (2.9-3.0%). Finally, the essential oil was submitted to enantioselective analysis, on two β-cyclodextrin-based chiral selectors, determining the enantiomeric distribution of seven chiral terpenes. Among them, (1R,5R)-(+)-α-pinene, (1R,5R)-(+)-β-pinene, and (R)-(-)-α-phellandrene were enantiomerically pure, whereas camphene, borneol, α-copaene, and α-terpineol were present as scalemic mixtures.

Targeting phosphoglycerate kinases by tatridin A, a natural sesquiterpenoid endowed with anti-cancer activity, using a proteomic platform

Tatridin A (TatA) is a germacrane sesquiterpenoid containing one E-double bond and one Z-double bond in its 10-membered ring, which is fused to a 3-methylene-dihydrofuran-2-one moiety. Tatridin A bioactivity has been poorly investigated despite its interesting chemical structure. Here, a functional proteomic platform was adapted to disclose its most reliable targets in leukemia monocytic cells, and phosphoglycerate kinases were recognized as the most affine enzymes. Through a combination of limited proteolysis and molecular docking, it has been discovered that tatridin A interacts with the active domains of phosphoglycerate kinase 1, altering its hinge region, and it can be accountable for tatridin A inhibition potency on enzyme activity. A more detailed tatridin A biological profile showed that it is also fully active against gastric cancer cells, downregulating the mRNA levels of chemokine receptor 4 and β-catenin and inhibiting the invasiveness of living KATO III cells as a direct consequence of phosphoglycerate kinase 1 antagonism.

Salvia dumetorum essential oil: GC-MS analysis, antibacterial activity and effect on the formation of Streptococcus mutans biofilms

Salvia dumetorum essential oil (SDEO) was obtained using a Clevenger apparatus by hydrodistillation approach. The chemical composition of the essential oil was determined by GC-MS analysis. In this study SDEO was screened for its antibacterial activity against Staphylococcus aureus, Bacillus subtilis, Escherichia coli, and Candida albicans and the amount of biofilm formed by Streptococcus mutans bacteria. For the first time the chemical composition of SDEO growing in Central Kazakhstan was established. The results obtained from GC-MS showed the predominance of sesquiterpenoids (54.15%). The antibacterial study results showed that SDEO exhibited strong antibacterial activity against B. subtilis and S. aureus in vitro and also demonstrated an inhibitory effect on S. mutans biofilm formation on 1% sucrose medium. During the study, no antibacterial activity was detected against E. coli and C. albicans. These results demonstrated that SDEO can be used in the development of new antibacterial and anti-caries therapeutic dental products.

Antimicrobial, Cytotoxic, and α-Glucosidase Inhibitory Activities of Ethanol Extract and Chemical Constituents Isolated from Homotrigona apicalis Propolis-In Vitro and Molecular Docking Studies

The chemical investigation of Homotrigona apicalis propolis collected in Binh Dinh province, Vietnam, led to the isolation of nine compounds, including four sesquiterpenes: spathulenol (1), 1αH,5βH-aromandendrane-4β,10α-diol (2), 1β,6α-dihydroxy-4(15)-eudesmene (3), and 1βH,5βH-aromandendrane-4α,10β-diol (4); three triterpenes: acetyl oleanolic acid (5), 3α-hydroxytirucalla-8,24-dien-21-oic acid (6), and ursolic acid (7); and two xanthones: cochinchinone A (8) and α-mangostin (9). Sesquiterpens 1-4 and triterpene 6 were isolated for the first time from stingless bee propolis. Plants in the Cratoxylum and Aglaia genus were suggested as resin sources of the propolis sample. In the antibacterial activity evaluation, the EtOH extract only showed moderate activity on S. aureus, while the isolated compounds 7-9 showed good antibacterial activity, with IC50 values of 0.56 to 17.33 µg/mL. The EtOH extract displayed selective cytotoxicity against the A-549 cancer cell line, with IC50 values of 22.82 ± 0.86 µg/mL, and the xanthones 8 and 9 exhibited good activity against the KB, HepG-2, and A-549 cancer cell lines, with IC50 values ranging from 7.55 ± 0.25 µg/mL to 29.27 ± 2.07 µg/mL. The cytotoxic effects of xanthones 8 and 9 were determined by the inhibition of the EGFR and HER2 pathways using a molecular docking study. Compounds 8 and 9 displayed strong binding affinity with EFGR and HER2, with values of -9.3 to -9.9 kcal/mol. Compounds 5, 8, and 9 showed potential α-glucosidase inhibitory activities, which were further confirmed by computational studies. The binding energies of compounds 5, 8, and 9 were lower than that of arcabose.

Phytochemistry, Biological, and Pharmacological Properties of Abies alba Mill

Abies alba Mill. (Pinaceae), silver fir, is a widespread gymnosperm species in Europe, important for its ecological, economic, social, and cultural significance, as well as for its use for food and bioremediation purposes. The various parts of the plant (leaves, branches, cones, wood, bark) are also of pharmaceutical interest due to their composition of active compounds. In the last three decades, an impressive amount of research has been dedicated to this species. The variability of the chemical composition of essential oils (whether they come from leaves, oleoresin from branches, or other parts of the plant) is impressive, even in the case of specimens collected from the same geographical area. For essential oils prepared from needles or twigs and branches, limonene, β-pinene, α-pinene, camphene, β-phellandrene, and bornyl acetate are the leading compounds, although their wide variations seem to correspond to multiple chemotypes. Both bark and wood are rich in lignans and phenolic compounds. Matairesinol is apparently the dominant lignan in bark, and secoisolariciresinol and lariciresinol are the dominant ones in wood samples. Pharmacological studies with promising results have evaluated the antioxidant effect (mainly due to essential oils), but also the antimicrobial, antitumor, probiotic, antidiabetic, anti-steatosis, and anti-psoriatic activities.

Three New Constituents with Anti-Inflammatory and Antimicrobial Activities in Vitro from the Roots of Capsicum annuum L

Three new compounds, including two new sesquiterpenes (1-2), named Annuumine E-F, and one new natural product, 3-hydroxy-2,6-dimethylbenzenemethanol (3), together with seventeen known compounds (4-20) were isolated from the ethanol extract of the roots of Capsicum annuum L. Among them, five compounds (4, 5, 9, 10 and 20) were isolated from this plant for the first time. The structures of new compounds (1-3) were determined via detailed analysis of the IR, HR-ESI-MS and 1D and 2D NMR spectra. The anti-inflammatory activities of the isolated compounds were evaluated by their ability to reduce NO release by LPS-induced RAW 264.7 cells. Notably, compound 11 exhibited moderate anti-inflammatory activity (IC50 =21.11 μM). Moreover, the antibacterial activities of the isolated compounds were also evaluated.

Comparative Analysis and Identification of Terpene Synthase Genes in Convallaria keiskei Leaf, Flower and Root Using RNA-Sequencing Profiling

The 'Lilly of the Valley' species, Convallaria, is renowned for its fragrant white flowers and distinctive fresh and green floral scent, attributed to a rich composition of volatile organic compounds (VOCs). However, the molecular mechanisms underlying the biosynthesis of this floral scent remain poorly understood due to a lack of transcriptomic data. In this study, we conducted the first comparative transcriptome analysis of C. keiskei, encompassing the leaf, flower, and root tissues. Our aim was to investigate the terpene synthase (TPS) genes and differential gene expression (DEG) patterns associated with essential oil biosynthesis. Through de novo assembly, we generated a substantial number of unigenes, with the highest count in the root (146,550), followed by the flower (116,434) and the leaf (72,044). Among the identified unigenes, we focused on fifteen putative ckTPS genes, which are involved in the synthesis of mono- and sesquiterpenes, the key aromatic compounds responsible for the essential oil biosynthesis in C. keiskei. The expression of these genes was validated using quantitative PCR analysis. Both DEG and qPCR analyses revealed the presence of ckTPS genes in the flower transcriptome, responsible for the synthesis of various compounds such as geraniol, germacrene, kaurene, linalool, nerolidol, trans-ocimene and valencene. The leaf transcriptome exhibited genes related to the biosynthesis of kaurene and trans-ocimene. In the root, the identified unigenes were associated with synthesizing kaurene, trans-ocimene and valencene. Both analyses indicated that the genes involved in mono- and sesquiterpene biosynthesis are more highly expressed in the flower compared to the leaf and root. This comprehensive study provides valuable resources for future investigations aiming to unravel the essential oil-biosynthesis-related genes in the Convallaria genus.

Three new sesquiterpenes from roots of Curcuma longa

Objective

To study the chemical constituents from the roots of Curcuma longa.

Methods

The structures of the compounds were elucidated based on extensive spectral analysis, including 1D and 2D NMR, MS, UV, and CD analysis.

Results

Two new sesquiterpene compounds (1S,2R,5R,7S,8R)-2,8-epoxy-5-hydroxybisabola-3,10-dioen-9-one (1), (1R,2R,5R,7S,8R)-2,8-epoxy-5-hydroxybisabola-3,10-dioen-9-one (2), and a new natural product 6-(4-Hydroxymethylphenyl)-2-methyl-hept-2-ene-4-one (3) together with three known compounds ar-turmerone (4), 2-methyl-6-(4-hydroxyphenyl-3-methyl)-2-hepten-4-one (5) and 2-methyl-6-(4-hydroxyphenyl)-2-hepten-4-one (6) were isolated from C. longa root extract with 95% ethanol.

Conclusion

In the study, three new compounds were isolated from C. longa, and their absolute configurations were determined.

Sesquiterpenes from Streptomyces qinglanensis and Their Cytotoxic Activity

Nine sesquiterpenes, including eight pentalenenes (1-8) and one bolinane derivative (9), were isolated from the culture broth of a marine-derived actinobacterium Streptomyces qinglanensis 213DD-006. Among them, 1, 4, 7, and 9 were new compounds. Their planar structures were determined by spectroscopic methods (HRMS, 1D, and 2D NMR), and the absolute configuration was established by biosynthesis consideration and electronic-circular-dichroism (ECD) calculations. All the isolated compounds were screened for their cytotoxicity against six solid and seven blood cancer cell lines. Compounds 4-6 and 8 showed a moderate activity against all of the tested solid cell lines, with GI₅₀ values ranging from 1.97 to 3.46 µM.

Antidepressant Effects of Essential Oils: A Review of the Past Decade (2012-2022) and Molecular Docking Study of Their Major Chemical Components

Depression is a mental disorder that affects more than 300 million people worldwide. The medications available for treatment take a long time to exhibit therapeutic results and present several side effects. Furthermore, there is a decrease in the quality of life of people suffering from this affliction. Essential oils are traditionally used to relieve the symptoms of depression due to the properties of the constituents of these oils to cross the blood-brain barrier acting on depression-related biological receptors associated with reduced toxicity and side effects. In addition, compared to traditional drugs, they have several administration forms. This review provides a comprehensive assessment of studies on plants whose essential oil has exhibit antidepressant activity in the past decade and the mechanism of action of the major components and models tested. An additional in silico study was conducted with the frequent compounds in the composition of these essential oils, providing a molecular approach to the mechanism of action that has been reported in the past decade. This review is valuable for the development of potential antidepressant medications in addition to providing a molecular approach to the antidepressant mechanism of action of the major volatile compounds that have been reported in the past decade.

An Enantiospecific Synthesis of 5-epi-α-Bulnesene

As a result of its unique fragrance and wider role in traditional medicine, agarwood produced in Aquilaria spp. and certain other trees has been harvested to near extinction as a natural phenomenon. Artificially induced agarwood production in Aquilaria plantations has sated some of the demand although the product quality is variable. Synthetic chemistry may have a role to play in providing sustainable routes to many of the fragrant components identified in agarwood and its smoke when burnt as incense. In this work, we report efforts towards a total synthesis of the guaiane sesquiterpene α-bulnesene, which is found, along with its more fragrant oxidised derivatives, in agarwood. Following the ring-expansion of (R)-carvone using reported procedures, α-butenylation gave a substrate for samarium diiodide mediated reductive cyclisation, the two butenyl epimers of the substrate each leading to a single bicyclic alcohol (24 and 25). Overall homoconjugate hydride reduction of one of these alcohols was achieved by Lewis acid-mediated ionisation and then hydride transfer from triethylsilane to complete an overall seven-step synthesis of 5-epi-α-bulnesene. This new synthesis paves the way for short routes to both α-bulnesene enantiomers and a study of their aerial and enzymatic oxidation products.

Characterization and Inhibitory Effects of Essential Oil and Nanoemulsion from Ocotea indecora (Shott) Mez in Aspergillus Species

The Aspergillus genus, the etiological agent of aspergillosis, is an important food contaminant and mycotoxin producer. Plant extracts and essential oils are a source of bioactive substances with antimicrobial potential that can be used instead of synthetic food preservatives. Species from the Lauraceae family and the Ocotea genus have been used as traditional medicinal herbs. Their essential oils can be nanoemulsified to enhance their stability and bioavailability and increase their use. Therefore, this study sought to prepare and characterize both nanoemulsion and essential oil from the Ocotea indecora's leaves, a native and endemic species from the Mata Atlântica forest in Brazil, and evaluate the activity against Aspergillus flavus RC 2054, Aspergillus parasiticus NRRL 2999, and Aspergillus westerdjikiae NRRL 3174. The products were added to Sabouraud Dextrose Agar at concentrations of 256, 512, 1024, 2048, and 4096 µg/mL. The strains were inoculated and incubated for up to 96 h with two daily measurements. The results did not show fungicidal activity under these conditions. A fungistatic effect, however, was observed. The nanoemulsion decreased the fungistatic concentration of the essential oil more than ten times, mainly in A. westerdjikiae. There were no significant changes in aflatoxin production.

Chemometrics of the Composition and Antioxidant Capacity of Hyptis crenata Essential Oils from Brazil

Hyptis crenata (Pohl) ex Benth is used in traditional medicine as an analgesic to treat general pain. Six Hyptis crenata samples (Hc-1 to Hc-6) were collected in Pará state, Brazil. The leaf essential oils were obtained by hydrodistillation, and GC-MS and GC-FID were used to analyze their chemical compositions. The antioxidant capacity was measured in vitro using DPPH and carotene/linoleic acid assays. Chemometrics analysis (PCA, HCA, and clustered heat map) were used to identify the sample relationships between those collected in this study and those from the literature (Hc-7 to Hc-16) samples. According to the main chemical constituents identified in the samples described in this work and the literature, the sixteen samples were classified into ten groups. Group I was characterized by 1,8-cineole (31.0%), α-pinene (13.6%), (E)-caryophyllene (7.8%), and β-pinene (7.6%); and Group IV was characterized by 1,8-cineole (17.4-23.5%), α-pinene (15.7-23.5%), β-pinene (10.5-13.4%), and limonene (8.5-9.7%). Both groups are described for the first time. The total antioxidant capacity was expressed in Trolox Equivalent Antioxidant Capacity values (TEAC): TEAC of Hc-5 (551.9 mg.TE/g) and Hc-6 (475.1 mg.TE/g). In the β-carotene/linoleic acid assay, the highest inhibition was from Hc-2 (40.0%), Hc-6 (39.0%), and Hc-3 (29.4%).

Two new sesquiterpenes from Xylopia vielana

Two new sesquiterpenes (1-2) and six known analogues (3-8) were isolated from the branches and leaves of Xylopia vielana Pierre. The structures of the new compounds were identified by analyzing 1 D and 2 D NMR data and HRESIMS data, combined with induced and calculated circular dichroism experiments. In addition, compounds 1-4, 7 and 8 showed notable nitric oxide (NO) inhibitory effects (IC₅₀ < 10 μM) on the model of the lipopolysaccharide (LPS)-activated RAW 264.7 macrophages.

Teucrium fruticans L., a multi-scale study: from trichomes to essential oil

This work represents the first multi-scale study on Teucrium fruticans L. cultivated at the Ghirardi Botanic Garden (Lombardy, Northern Italy), combining a micromorphological and a phytochemical survey on the plant's aerial parts. Micromorphological investigations highlighted the presence of five trichomes morphotypes, distinguished by a different distribution pattern: peltates, short-stalked and ball-like medium-stalked capitates, ubiquitous on the whole plant, medium-stalked and long-stalked capitates, exclusive to the floral whorls. Both peltates and medium-stalked capitates were recognized as the main terpene production sites. Phytochemical characterization focused on the essential oils, obtained by Clevenger-type hydrodistillation in February and April 2022, which resulted mainly formed by sesquiterpene hydrocarbons. The February EO profile was characterized by β-caryophyllene and germacrene D as main compounds, while in April β-myrcene was detected at high percentage in addition to the previous two components. Literature data, dealing with the biological activities of the main oil constituents, highlighted an anti-microbial, anti-inflammatory, and anti-tumor potential, due to the high content in sesquiterpenes and, particularly, of β-caryophyllene and germacrene D.

Chemical Diversity of Artemisia rutifolia Essential Oil, Antimicrobial and Antiradical Activity

This paper presents the results of the study of the composition of the essential oil (EO) of Artemisia rutifolia by the GC/MS method as well as its antimicrobial and antiradical activities. According to the PCA-analysis, these EOs can be conditionally divided into "Tajik" and "Buryat-Mongol" chemotypes. The first chemotype is characterized by the prevalence of α- and β-thujone, and the second chemotype by the prevalence of 4-phenyl-2-butanone, camphor. The greatest antimicrobial activity of A. rutifolia EO was observed against Gram-positive bacteria and fungi. The EO showed high antiradical activity with an IC₅₀ value of 17.55 μL/mL. The presented first data on the composition and activity of the EO of A. rutifolia of the Russian flora indicate the prospects of the species as a raw material for the pharmaceutical and cosmetic industry.

Separation and identification of terpene-conjugated curcuminoids based on liquid chromatography-tandem mass spectrometry and their in vitro anti-inflammatory activities

Terpene-conjugated curcuminoids are conjugates of curcuminoids and bisabolanes in the rhizomes of Curcuma longa L. The fragmentation pathways of known three terpene-conjugated curcuminoids (bisabolocurcumin-ether, bisabocurcumin, and demethoxybisabolocurcumin ether) and curcumin, demethoxycurcumin, and bisdemethoxycurcumin were investigated using high-performance liquid chromatography-electrospray ionization tandem mass spectrometry in negative mode to rapidly search and discover similar unknown compounds of the acetone fraction of turmeric. Subsequently, compounds 1-3 were founded in the acetone fraction based on molecular weight and above fragmentation pathways (the characteristic fragment ions, the most and second most abundant fragment ions produced in MS² spectra). Terpecurcumin X (1) and terpecurcumin Y (3) were further separated by liquid chromatography-tandem mass spectrometry guided isolation technique to verify their structures by nuclear magnetic resonance, electrospray ionization high-resolution mass spectroscopy, ultraviolet and visible spectra and infrared spectra. Interestingly, 1 and 3 were new compounds. The results indicate the feasibility and significant advantages of liquid chromatography-tandem mass spectrometry for the rapid discovery and analysis of new constituents in traditional Chinese medicine. In vitro, Terpene-conjugated curcuminoids had better nitric oxide inhibitory activity than the other seven curcuminoids (demethoxycurcumin, bisdemethoxycurcumin, curdione, curcumenone, bisacurone, curcumenol, and germacron).

Genetic and physiological requirements for high-level sesquiterpene-production in tomato glandular trichomes

Type-VI glandular trichomes of wild tomato Solanum habrochaites PI127826 produce high levels of the sesquiterpene 7-epizingiberene and its derivatives, making the plant repellent and toxic to several pest insects and pathogens. How wild tomato trichomes achieve such high terpene production is still largely unknown. Here we show that a cross (F1) with a cultivated tomato produced only minute levels of 7-epizingiberene. In the F2-progeny, selected for the presence of the 7-epizingiberene biosynthesis genes, only three percent produced comparable amounts the wild parent, indicating this trait is recessive and multigenic. Moreover, trichome density alone did not explain the total levels of terpene levels found on the leaves. We selected F2 plants with the "high-production active-trichome phenotype" of PI127826, having trichomes producing about 150 times higher levels of terpenes than F2 individuals that displayed a "low-production lazy-trichome phenotype". Terpene quantities in trichomes of these F2 plants correlated with the volume of the storage cavity and shape of the gland. We found that trichome morphology is not a predetermined characteristic, but cavity volume rather depended on gland-cell metabolic activity. Inhibitor assays showed that the plastidial-precursor pathway (MEP) is fundamental for high-level production of both cytosolic as well as plastid-derived terpenes in tomato trichomes. Additionally, gene expression profiles of isolated secretory cells showed that key enzymes in the MEP pathway were higher expressed in active trichomes. We conclude that the MEP pathway is the primary precursor-supply route in wild tomato type-VI trichomes and that the high-production phenotype of the wild tomato trichome is indeed a multigenic trait.

[Chemical constituents in Dolomiaea plants and their pharmacological activities: a review]

Dolomiaea plants are perennial herbs in the Asteraceae family with a long medicinal history. They are rich in chemical constituents, mainly including sesquiterpenes, phenylpropanoids, triterpenes, and steroids. The extracts and chemical constituents of Dolomiaea plants have various pharmacological effects, such as anti-inflammatory, antibacterial, antitumor, anti-gastric ulcer, hepatoprotective and choleretic effects. However, there are few reports on Dolomiaea plants. This study systematically reviewed the research progress on the chemical constituents and pharmacological effects of Dolomiaea plants to provide references for the further development and research of Dolomiaea plants.

Chemical Composition of Essential Oils and Local Knowledge of Myrica gale in Lithuania

Myrica gale L. (Myricaceae) is an essential oil-bearing plant that is rare in Lithuania and naturally grows only in the western part of the country. The aim of this study was to analyze the composition of essential oils of Myrica gale in different habitats in Lithuania and in different parts of the plant, as well as evaluate the local knowledge about M. gale as a medicinal and aromatic plant. Samples of fruits and leaves (from one and three M. gale populations, respectively) were studied separately. Essential oils were isolated from dried fruits and leaves by hydrodistillation and analyzed by GC/FID and GC/MS methods. Results showed that M. gale fruits accumulated 4.03 ± 2.13% essential oils, meanwhile leaves-up to 19 times less. A total of 85 compounds were identified in the essential oils of the M. gale. Monoterpene hydrocarbons accounted for about half of the total essential oil content; meanwhile, either monoterpene hydrocarbons or sesquiterpene hydrocarbons (depending on habitat) dominated in leaves. The main compounds (depending on habitat) in essential oils of fruits and leaves were α-pinene, 1,8-cineole, limonene, δ-cadinene, and (E)-nerolidol. The high variation in the composition of M. gale essential oils suggests the presence of different chemotypes within the studied habitats of this plant. Evaluation of local knowledge of M. gale through the survey of 74 residents of 15 villages in western Lithuania showed that only 7% of respondents knew this plant. Poor knowledge of M. gale could be related to the narrow range of the natural species' distribution in Lithuania.