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Ganoderma lucidum, a medicinal mushroom with a long history in traditional Chinese medicine, is widely used for chronic diseases. Ganospirones A-G (1-7), seven pairs of undescribed spiro-meroterpenoids, were isolated from the fruiting bodies of G. lucidum. Their structures including absolute configurations were characterized by using NMR spectroscopic data, ECD computational and X-ray diffraction methods. The anti-inflammatory and anti-renal fibrosis activities of the meroterpenoids 1-7 were tested, and the results revealed that (-)-2 and (+)-2 could inhibit iNOS expression in lipopolysaccharide-induced RAW264.7 cells at 20 μM., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The genus Penicillium has provided us with the household antibiotic penicillin and the well-known lipid-lowering agent mevastatin. The strain Penicillium sp. SZ-1 was found to grow vigorously in an intact Pinus koraiensis seed, it is inferred that the strain may develop unique mechanisms associated with the biosynthesis of rare metabolites. Further fermentation of the strain on solid rice medium yielded thirteen undescribed compounds, including three andrastin-type meroterpenoids (1-3), two α-pyrone polyketides (4 and 5), and eight sesquicarane derivatives (6-13), along with seven known compounds (14-20). Their structures were determined by detailed analysis of the spectroscopic and spectrometric data (NMR and HRESIMS), in addition to comparisons of the experimental and calculated ECD data for absolute configurational assignments. The hemiacetal moiety in compounds 1 and 2 and the 3α-hydroxy group in compound 3 were rarely found in the andrastin-type meroterpenoid family. The sesquicaranes belong to a small group of sesquiterpenoid that are rarely reported. Bioassay study showed that compound 1 exhibited inhibitory effects against Staphylococcus aureus ATCC 29213 and Escherichia coli ATCC 25922 with MIC values of 64 and 32 μg/mL, respectively. In addition, compounds 1 and 3 displayed weak DPPH radical scavenging activities. The andrastins and sesquicaranes in this study enriched the structural diversity of these classes of terpenoids. Of note, this study is the first report on the metabolites of a fungus isolated from P. koraiensis seed., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Rhododendron dauricum L. is a perennial herb belonging to the genus Rhododendron, commonly utilized in formulations for treating coughs and bronchitis, as well as in herbal teas for enhancing immunity and preventing tracheitis. In this study, fifteen previously undescribed chromene meroterpenoids (1a/1b-4a/4b, 5-8, 9b, 10a, 11b), along with twenty-one known compounds were isolated from the dried twigs and leaves of Rhododendron dauricum L. Of these, (-)-rhodonoid E (9b), (+)-confluentin (10a), and (-)-rubiginosin D (11b) were separated for the first time by chiral HPLC separation. The elucidation of their structures, including absolute configurations, was achieved through a combination of techniques such as NMR, HRESIMS, modified Mosher's method and quantum-chemical calculation of electronic circular dichroism (ECD) spectra. Seven pairs of enantiomers, compounds 1a/1b-4a/4b and 9a/9b-11a/11b, were initially obtained in a racemic manner and were further separated by chiral HPLC preparation. The biological assessment of these compounds against NO production was conducted in the LPS-induced RAW264.7 macrophage cells model. Compounds 9a, 9b, and 11a displayed inhibitory rates exceeding 80%, with IC 50 values ranging from 8.69 ± 0.94 to 13.01 ± 1.11 μM. A preliminary examination of the structure-activity relationship (SAR) for these isolates indicated that chromene meroterpenoids with α, β-unsaturated ketone carbonyl and Δ 12(13) double bond functionalities exhibited enhanced anti-inflammatory properties., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Terpenes, volatile compounds known for their aromatic and therapeutic properties, play a pivotal role in shaping the overall chemical profile of Cannabis sativa L. Their biosynthesis in planta occurs in trichomes and involves the 2-C-methyl-D-erythritol 4-phosphate (MEP) and the mevalonic acid (MVA) pathways, responsible for producing the substrates utilized by a family of enzymes, the terpene synthases (TPS), for terpene production. In this work, a comprehensive approach combining chemical analyses of the volatile compounds characterizing the aroma of the inflorescences three C. sativa genotypes collected at three stages of maturity and the transcriptional analyses of key genes involved in the terpene biosynthesis was adopted to study this pathway. The results revealed different terpene profiles among genotypes, which were characterized by peculiar compounds belonging to the sesqui- (CINBOL and Fibrante) or monoterpene (Ermo) categories. Both structural and putative regulatory genes were analysed by RT-qPCR, revealing distinct transcriptional profiles of Terpene Synthases, contributing to the diversity of mono and sesquiterpenes synthesized. Furthermore, the research delved into potential regulatory genes associated with trichome formation, a crucial factor influencing terpene accumulation. This integrated approach highlighted complex mechanisms governing terpene accumulation in cannabis, while also offering potential regulators putatively involved in this pathway., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Achillea alpina L. (Alpine yarrow) is a noteworthy herb in the genus Achillea with many uses in vegetables and traditionally used to treat stomach disorders. In our continuous research on the chemical constituents and biological activities of medicinal plants, ten previously undescribed terpenoids including eight eudesmane-type sesquiterpenes (1-8), one nor-eudesmane-type sesquiterpene (9), one cyclo-geraniol derivative (10), and twenty-one known compounds were isolated and structurally elucidated from the aerial parts of A. alpina. Structures and absolute configurations of the undescribed terpenoids were identified using comprehensive spectroscopic analysis (NMR, HRESI-MS, and CD data) and computational methods (ECD and NMR calculation). Enzyme inhibitory assays showed that the isolated sesquiterpene (19), triterpene (22), and sterol (26) were protein tyrosine phosphatase 1B (PTP1B) inhibitors with IC 50 values ranging from 14.87 to 23.09 μM in comparison with positive control - ursolic acid, showing IC 50 value of 5.93 ± 0.16 μM. Further enzyme kinetics and molecular docking studies were performed to provide valuable insights into their mechanism of action., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Six pairs of previously undescribed enantiomeric phytocannabinoid-like meroterpenoids, (±)-spinulinoids A‒F, and two naturally occurring compounds, (+)-rhododaurichromanic acid A and (E)-4-((3,7-dimethylocta-2,6-dien-1-yl)oxy)benzoic acid, together with one known congener, (-)-rhododaurichromanic acid A, were obtained from the twigs and leaves of Rhododendron spinuliferum. Their structures were established by their extensive spectral data (NMR and HRESIMS), ECD calculations, and single-crystal X-ray diffraction data. Spinulinoids A and B are unprecedented phytocannabinoid-like meroterpenoids constructed by the resorcinol moiety and a β-bisabolene unit, whereas spinulinoid C represents a rare adduct of quinone and β-bisabolene with a tricyclic 6/6/6 ring system., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Meroterpenoids discovered in Rhododendrons species possess unique chemical structures and biological activities and are expected to become new drug targets for Alzheimer's disease, metabolic disorders, and chronic kidney disease, and these compounds have attracted increasing attention in recent years. In this study, Rhododendron meroterpenoids and their structures, classifications, racemate distribution, biosynthetic pathways, chemical synthesis, and bioactivities are reviewed prior to 2023., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The Ganoderma lucidum mushroom, which has been used as a traditional medicine in China for more than 2000 years, is a source of many interesting natural product. In this study, the five undescribed minor meroterpenoids baoslingzhines F-J (1-5), containing a dihydropyran moiety, were isolated as racemic mixtures from the fruiting bodies of G. lucidum. These substances were structurally and stereochemically characterized by using spectroscopic and computational methods. Chiral HPLC was employed to separate the (+)- and (-)-antipodes. A survey of the activities against kidney fibrosis showed that both enantiomers of baoslingzhines F-J inhibit expression of renal fibrosis-related proteins, including fibronectin, collagen I and ɑ-SMA in TGF-β1-induced rat kidney proximal tubular cells., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

The fruiting bodies of Ganoderma sinensis are used as food raw materials of marketed healthcare products. To gain an insight into the chemical and biological profling of G. sinensis, twenty-five compounds including eleven undescribed ones (ganodermasines A‒K) and fourteen known ones were isolated. Among them, ganodermasines A‒D are undescribed diketopiperazine alkaloids, ganodermasines E and F are alkaloids containing a pyridine. The structures of undescribed compounds were identified by spectroscopic, computational, and crystallographic methods. The results of acetylcholinesterase (AchE) inhibitory activity show that ganodermasines I and J could inhibit AchE with IC 50 values of 26.05 and 20.40 μM, respectively. In addition, neurotrophic assay in PC-12 cells showed that (+)-ganodermasine E, (-)-ganodermasine E, and ganodermasine I could stimulate neurite outgrowth at 10 μM, while the other isolates are inactive. The present findings will lend a hand for further utilization of G. sinensis., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Five undescribed benzopyran containing meroterpenoids, ganodercins Q－U, two undescribed benzofuran containing meroterpenoids, ganodercins V and W, and two known meroterpenoids were isolated from Ganoderma cochlear. Their structures were elucidated by using HRESIMS, NMR spectroscopy and computational methods. The results of biochemical studies using a palmitic acid (PA) induced insulin resistance (IR) model show that (-)-ganodercin Q, (+)-ganodercins R and W activate phospho-AKT (p-AKT) at 20 μM and improve glucose uptake in a concentration dependent manner. The results of renoprotection studies show that (+)-ganodercin S, cochlearol F, (+)- and (-)-ganodercins V reduce the expression of collagen I., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Chemical fractionation of the ethanolic extract of Eclipta prostrata yielded a series of unreported terpenoid constituents, including a rare 6/6/6/6-fused tetracyclic triterpenoid, a pentacyclic triterpenoid, two pentacyclic triterpenoid saponins, a diterpenoid and a sesquiterpenoid. Structures were assigned to these compounds on the basis of comprehensive spectroscopic analyses, with the absolute configurations of the tetracyclic triterpenoid, the diterpenoid and the sesquiterpenoid being determined via explanation of electronic circular dichroism data. Screening of these isolates in an array of bioassays revealed antibacterial, cytotoxic and α-glucosidase inhibitory activities for selective compounds. Of particular interest, the tetracyclic triterpenoid showed very strong inhibition against α-glucosidase with an IC 50 of 0.82 ± 0.18 μM, being 10 3 -fold as active as the positive control acarbose., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

A phytochemical investigation on the MeOH extract of the twigs and needles of the endangered plant Picea brachytyla led to the isolation and characterization of thirty-eight structurally diverse terpenoids. Seven of these molecules are previously undescribed, including three abietane-type (brachytylins A-C) and one labdane-type (brachytylin D) diterpenoids, an unseparated C-24 epimeric mixture of cycloartane-type triterpenoids (brachytylins E/F, ratio: 1:1), and a rare rearranged 12(1 → 6)-abeo-megastigmane glycoside (brachytylins G). Their structures and absolute configurations were determined by extensive spectroscopic (e.g., detailed 2D NMR and ECD) methods and/or X-ray diffraction analyses. All the isolates were evaluated for their inhibitory activities against the adenosine triphosphate (ATP)-citrate lyase (ACL) and the Src homology-2 domain containing protein tyrosine phosphatase-2 (SHP2). Among them, abiesadine J showed inhibitory effect against ACL, displaying an IC 50 value of 17 μM. 3S,23R-Dihydroxycycloart-24-en-26-oic acid exhibited inhibitory effect on SHP2, with an IC 50 value of 19 μM. Meanwhile, 3R*,23S*-dihydroxycycloart-24-en-26-oic acid was found to have inhibitory effects against both ACL and SHP2, with IC 50 values of 16 and 12 μM, respectively., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Spiroterreusnoids A-F, six undescribed spiro-dioxolane-containing adducts bearing 3,5-dimethylorsellinic acid-based meroterpenoid and 2,3-butanediol moieties were isolated from the endophytic fungus Aspergillus terreus Thom from Tripterygium wilfordii Hook. f. (Celastraceae). The structures of these adducts were established by spectroscopy, single-crystal X-ray diffraction, and experimental electronic circular dichroism (ECD) measurements. Spiroterreusnoids A-F represent the first examples of adducts composed of 3,5-dimethylorsellinic acid-based meroterpenoids. It is noteworthy that spiroterreusnoids A-F possessing a spiro-dioxolane moiety exhibited potential abilities in inhibiting BACE1 (IC 50 values ranging from 5.86 to 27.16 μM) and AchE (IC 50 values ranging from 22.18 to 32.51 μM), while the other analogues without this fragment displayed no such activities. Taken together, spiroterreusnoids A-F represent the first multitargeted natural adducts that could inhibit BACE1 and AchE, and might provide a new template for the development of new anti-Alzheimer's disease drugs., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Mangiterpenes A-C and 2',3'-seco-manginoid C, four undescribed sesquiterpene/monoterpene-shikimate-conjugated meroterpenoids with spiro ring systems, were isolated from Guignardia mangiferae. The structures and absolute configurations of these compounds were established by comprehensive spectroscopic analyses and electronic circular dichroism (ECD) calculations. Mangiterpenes A-C represent the first examples of sesquiterpene-shikimate-conjugated spirocyclic meroterpenoids, and 2',3'-seco-manginoid C features an unexpected 2',3'-seco-manginoids skeleton. Mangiterpene C strongly inhibited the production of NO inducted by LPS, with an IC 50 value of 5.97 μM. It showed an anti-inflammatory effect by means of blocking in the NF-κB signaling pathway and decreasing the expression of inflammatory mediators., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Eleven highly oxygenated meroterpenoids, named terreustoxins A-K, along with five known analogues, were isolated from the Antarctic fungus Aspergillus terreus. The structures and absolute configurations of these undescribed compounds were characterized by NMR spectroscopy, single-crystal X-ray crystallography, and ECD experiments. Terreustoxins A-D are the first examples of meroterpenoids with two ortho-hydroxy groups at C-6 and C-7 in the terretonins family. Terreustoxin C and terretonin inhibited the proliferation of Con A-induced murine T cells at the concentration of 10 μM., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

The 95% ethanol extract and its EtOAc and n-BuOH fractions obtained from the leaves and twigs of Schefflera rubriflora C. J. Tseng & G. Hoo showed significant inhibitory activities (33.6%, 35.7% and 40.6%, respectively) against croton oil-induced ear inflammation in mice. Bioactivity-guided isolation and separation gave eight previously undescribed terpenes or terpene glycosides. Structural elucidation was based on UV, IR, and NMR spectroscopy, MS, experimental and calculated ECD data, and Mosher's method. To identify anti-inflammatory components from the extract, all the compounds were evaluated for tumor necrosis factor-α (TNF-α) and interleukine-6 (IL-6) inhibitory activities. Four undescribed compounds inhibited mRNA expression of TNF-α and IL-6 with IC 50 values of 15.3-52.4 μM., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Twelve formyl phloroglucinol meroterpenoids (FPMs) were isolated from the leaves of Eucalyptus robusta Smith. Their structures were elucidated via spectroscopic data analysis, the circular dichroism (CD) exciton chirality method, Rh 2 (OCOCF 3 ) 4 -induced CD experiments, and application of the Snatzke chirality rules. Eucalrobusones Q, S, and X are the first FPMs that have been identified in which the C-7' of phloroglucinol is linked to the C-15 of cadinane, the C-4 of cubebane, and the C-8 of menthane, respectively. (+)-Eucalrobusone X exhibited the most potent antifungal ability against Candida albicans with a MIC 50 value of 10.78 μg/mL, and eucalrobusone U exhibited the greatest anti-C. glabrata activity with MIC 50 value of 1.53 μg/mL., (Copyright © 2019. Published by Elsevier Ltd.)

Twelve previously undescribed phenolic meroterpenoids, cochlearols N-Y, along with two known analogs, ganocochlearins B and C, were isolated from the fruiting bodies of Ganoderma cochlear. Most of these substances were isolated as racemic mixtures. The structures of cochlearols N-Y were assigned based upon spectroscopic data and theoretical calculations. The renoprotective activities of these compounds were evaluated using normal and diseased rat renal interstitial fibroblast cells (NRK-49F). The results show that ganocochlearins S, U, X and Y display potent inhibitory activities against fibronectin overproduction in TGF-β1-induced NRK-49F cells., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Fifteen undescribed and five known lanostane-type C 31 triterpenoid derivatives were isolated from the aqueous EtOH extract of the fruiting bodies of cultivated Fomitopsis palustris. Their structures were identified from the spectroscopic data and chemical degradation studies. The structures of palustrisoic acids A and H were confirmed by X-ray crystallography. Polyporenic acid B showed strong cytotoxicity against the HCT116, A549, and HepG2 cell lines with IC 50 values of 8.4, 12.1, and 12.2 μM, respectively. Palustrisolides A, C, and G displayed weak cytotoxicity., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Coumarins and meroterpene from the fruits of Cullen corylifolium were evaluated for their ability to bind and activate human estrogen receptor α (hERα) by a combination of in vitro studies and molecular dynamics simulations. The recombinant hERα ligand binding domain (hERα-LBD) was produced in BL21 (DE3)pLysS and the fluorescence polarization (FP) assay was performed to determine the binding affinities of coumarins and meroterpene with receptor protein. These compounds displayed distinct binding potency toward hERα-LBD, generally increased with their increasing molecular length and Connolly solvent-excluded volume (CSEV). In an estrogen response element-luciferase (ERE-Luc) reporter gene assay, coumarins and meroterpene acted as agonists of human estrogen receptor α. Subsequently, molecular docking was conducted to elucidate the molecular mechanism behind their agonistic activities. Coumarins and meroterpene adopted an agonist conformation within the cavity of hERα-LBD. The hydrophobic and hydrogen-bonding interactions were dominant forces to stabilize their binding. The structure-activity relationship analysis suggested that the presence of hydroxyl groups and prenyl group were crucial for possessing estrogenic activities. Comparison of the calculated binding energies with the determined binding affinities yielded a good correlation (R 2  = 0.9727). In conclusion, molecular modeling techniques can potentially be applied for in silico screening of selective estrogen receptor modulators (SERMs) from undescribed compounds., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Phytochemical investigations of the aerial parts of the plant Cephalaria taurica Szabó. (Caprifoliaceae) have resulted in the isolation of nine oleanane-type triterpenoid saponins, of which two still remain undescribed. The structures of tauricosides A and B were characterized based on NMR analysis, HRESIMS spectrometry, and chemical evaluations. The saponins tauricosides A and B have been rarely reported in the literature due to the presence of eight sugar moieties, and this is also the first report of saponins containing eight sugar moieties in the Caprifoliaceae family. The cytotoxic activities of tauricosides A and B, their undescribed prosapogenins, aglycone hederagenin, and n-butanol extract of C. taurica against the cancerous cells A-549, HeLa, PANC-1, and SH-SY5Y and the noncancerous HEK-293 cells were evaluated by the MTT method. Although tauricosides A and B and the crude n-butanol extract did not exhibit any activity at the tested concentrations on all the tested cells, after alkaline hydrolysis, the cytotoxic activity potential of the compounds was obviously improved. The most active compound, obtained after the alkaline hydrolysis of tauricoside B, showed a significant inhibitory effect, which was higher than that of the standard, commercially available drug doxorubicin, on the cancerous A-549, HeLa, PANC-1, and SH-SY5Y cells with IC 50 values of 9.04, 8.75, 6.87, and 4.32 μM, respectively. In addition, prosapogenin, obtained after the alkaline hydrolysis of tauricoside A, exhibited considerable cytotoxic activity on the cancerous A-549, HeLa, PANC-1, and SH-SY5Y cells, with IC 50 values of 13.19, 10.32, 11.91, and 7.49 μM, respectively. In conclusion, the alkaline hydrolysis of the saponins (tauricosides A and B) obviously improved their cytotoxic activity potential., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Eight undescribed triterpenoid saponins together with a known one, and two undescribed sesquiterpene glycosides were isolated from root's barks of Eriocoelum microspermum. Their structures were elucidated by spectroscopic methods including 1D and 2D experiments in combinaison with mass spectrometry as 3-O-α-L-rhamnopyranosyl-(1 → 3)-[α-L-rhamnopyranosyl-(1 → 2)]-α-L-arabinopyranosylhederagenin, 3-O-α-L-rhamnopyranosyl-(1 → 3)-[β-D-glucopyranosyl-(1 → 3)-α-L-rhamnopyranosyl-(1 → 2)]-α-L-arabinopyranosylhederagenin, 3-O-α-L-rhamnopyranosyl-(1 → 3)-[β-D-xylopyranosyl-(1 → 3)-α-L-rhamnopyranosyl-(1 → 2)]-α-L-arabinopyranosylhederagenin, 3-O-α-L-rhamnopyranosyl-(1 → 4)-[α-L-rhamnopyranosyl-(1 → 2)]-α-L-arabinopyranosylhederagenin 28-O-β-D-glucopyranosyl ester, 3-O-α-L-rhamnopyranosyl-(1 → 3)-β-D-xylopyranosyl-(1 → 4)-β-D-xylopyranosyl-(1 → 3)-α-L-rhamnopyranosyl-(1 → 2)-α-L-arabinopyranosylhederagenin, 3-O-α-L-rhamnopyranosyl-(1 → 3)-α-L-arabinopyranosyl-(1 → 4)-β-D-xylopyranosyl-(1 → 3)-α-L-rhamnopyranosyl-(1 → 2)-α-L-arabinopyranosylhederagenin, 3-O-β-D-xylopyranosyl-(1 → 4)-α-L-arabinopyranosyl-(1 → 4)-β-D-glucopyranosyl-(1 → 3)-α-L-rhamnopyranosyl-(1 → 2)-α-L-arabinopyranosylhederagenin, 3-O-α-L-rhamnopyranosyl-(1 → 4)-α-L-rhamnopyranosyl-(1 → 3)-α-L-arabinopyranosyl-(1 → 4)-β-D-glucopyranosyl-(1 → 3)-α-L-rhamnopyranosyl-(1 → 2)]-α-L-arabinopyranosylhederagenin, 1-O-{β-D-xylopyranosyl-(1 → 3)-[α-L-rhamnopyranosyl-(1 → 2)]-β-D-glucopyranosyl-(1 → 4)-α-L-rhamnopyranosyl-(1 → 6)}-[β-D-xylopyranosyl-(1 → 3)]-[α-L-rhamnopyranosyl-(1 → 2)]-β-D-glucopyranosyl-(2E,6E)-farnes-1-ol, 1-O-{β-D-glucopyranosyl-(1 → 3)-[α-L-rhamnopyranosyl-(1 → 2)]-β-D-glucopyranosyl-(1 → 4)-α-L-rhamnopyranosyl-(1 → 6)}-[β-D-xylopyranosyl-(1 → 3)]-[α-L-rhamnopyranosyl-(1 → 2)]-β-D-glucopyranosyl-(2E,6E)-farnes-1-ol. These results represent a contribution to the chemotaxonomy of the genus Eriocoelum highlighting farnesol glycosides as chemotaxonomic markers of the subfamily of Sapindoideae in the family of Sapindaceae., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Schizonepeta tenuifolia Briquet, commonly known as Japanese catnip, is used for the treatment of colds, headaches, fevers, and skin rashes in traditional Asian medicine (China, Japan and Korea). The volatile oil and its constituents have various demonstrated biological activities, but there is currently limited information regarding the site of biosynthesis. Light microscopy and scanning electron microscopy indicated the presence of three distinct glandular trichome types which, based on their morphological features, are referred to as peltate, capitate and digitiform glandular trichomes. Laser scanning microscopy and 3D reconstruction demonstrated that terpenoid-producing peltate glandular trichomes contain a disk of twelve secretory cells. The oil of peltate glandular trichomes, collected by laser microdissection or using custom-made micropipettes, was demonstrated to contain (-)-pulegone, (+)-menthone and (+)-limonene as major constituents. Digitiform and capitate glandular trichomes did not contain appreciable levels of terpenoid volatiles. The yield of distilled oil from spikes was significantly (44%) higher than that from leaves, while the composition of oils was very similar. Oils collected directly from leaf peltate glandular trichomes over the course of a growing season contained primarily (-)-pulegone (>80% at 32 days after germination) in young plants, while (+)-menthone began to accumulate later (>75% at 80 days after germination), at the expense of (-)-pulegone (the levels of (+)-limonene remained fairly stable at 3-5%). The current study establishes the morphological and chemical characteristics of glandular trichome types of S. tenuifolia, and also provides the basis for unraveling the biosynthesis of essential oil in this popular medicinal plant., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

A total of 80 individuals collected from eight populations growing wild in different geographic zones were considered to assess the intraspecific variability of essential oil composition, genetic diversity and population structure of Artemisia herba-alba. The essential oil composition varied significantly between populations. Essential oil profiles were classified into four chemotypes (trans-sabinyl acetate, α-thujone/trans-sabinyl acetate, camphor and α-thujone/camphor/β-thujone). Despite significant correlation between the amount of some essential oil compounds and a set of climatic data, the global chemical divergence among populations was not related to their bioclimatic and geographic appurtenances. A high level of genetic diversity within populations was revealed either with RAPD and ISSR markers (Na = 1.67, PPL = 66.5%, H = 0.26, I = 0.38 and Na = 1.7, PPL = 69.8%, H = 0.26, I = 0.38, respectively). The level of genetic diversity varied across populations and chemotypes. Populations from the α-thujone/trans-sabinyl acetate chemotype exhibited the highest genetic diversity as revealed by the RAPD markers. However, populations from α-thujone/camphor/β-thujone chemotype showed the important genetic variation determined by ISSR markers. A significant genetic differentiation among populations and among chemotypes was detected. The combined analysis showed a significant correlation (r = 0.484, p = .032) between the chemical and molecular markers. The PCA, performed on percentages of major oil compounds and the frequencies of polymorphic RAPD and ISSR bands, divided populations according to their chemotypic classification. Taking into consideration the current situation of A. herba-alba populations and their endangered habitats, these results are of value in order to ensure the in-situ and ex-situ conservation of this medicinal species., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Molecular identification suggested an edible mushroom, which was previously named as Craterellus odoratus should be revised as Montagnula donacina. A chemical re-investigation of the culture broth of this fungus resulted in the isolation of four rare tetracyclic bergamotane-type sesquiterpenoids, namely donacinolides A and B, donacinoic acids A and B, and three cadinane-type ones, namely donacinols A-C and a meroterpenoid (Z)-4-hydroxy-3-(3-hydroxy-3-methylbut-1-en-1-yl)benzoic acid. Their structures were established via extensive spectroscopic methods, single crystal X-ray diffraction analysis, and computational methods. (Z)-4-Hydroxy-3-(3-hydroxy-3-methylbut-1-en-1-yl)benzoic acid showed antibacterial activity against Staphylococcus aureus., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Four previously undescribed meroterpenoids, amestolkolides A-D, along with three known compounds were isolated from the mangrove endophytic fungus Talaromyces amestolkiae YX1 cultured on wheat solid-substrate medium culture. Their structures were elucidated by a combination of spectroscopic analyses. The absolute configurations of amestolkolides B and C, and purpurogenolide E were determined by single-crystal X-ray diffraction using Cu Kα radiation, and those of amestolkolides A and D were elucidated on the basis of experimental and calculated electronic circular dichroism spectra. The absolute configuration of amestolkolides A-D, and purpurogenolide E (9R) at C-9 was different from that of analogues (9S) in references, so that their plausible and distinct biosynthetic pathways were proposed. Amestolkolide B showed strong anti-inflammatory activity in vitro by inhibiting nitric oxide (NO) production in lipopolysaccharide activated in RAW264.7 cells with IC 50 value of 1.6 ± 0.1 μM., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Brown seaweed Anthophycus longifolius (Turner) Kützing (family Sargassaceae) associated heterotrophic bacterium Bacillus subtilis MTCC 10403 was found to be a potent isolate with broad range of antibacterial activity against important perceptive food pathogens Vibrio parahaemolyticus, V. vulnificus, and Aeromonas hydrophila. This bacterium was positive for polyketide synthetase gene (KC589397), and therefore, was selected to bioprospect specialized metabolites bearing polyketide backbone. Bioactivity-guided chromatographic fractionation of the ethyl acetate extract of the seaweed-associated bacterium segregated four homologous polyketide furanoterpenoids with potential antibacterial activities against clinically important pathogens. The minimum inhibitory concentration (MIC) assay showed that the referral antibiotics tetracycline and ampicillin were active at 25 μg/mL against the test pathogens, whereas the previously undescribed (4E)-methyl 13-((16-(furan-2-yl) ethyl)-octahydro-7-hydroxy-4-((E)-23-methylbut-21-enyl)-2H-chromen-6-yl)-4-methylpent-4-enoate (compound 1) and methyl 3-(hexahydro-9-((E)-3-methylpent-1-enyl)-4H-furo[3,2-g]isochromen-6-yl) propanoate (compound 3) displayed antibacterial activities against the test pathogens at a lesser concentration (MIC < 7 μg/mL). The title compounds were characterized by comprehensive nuclear magnetic resonance and mass spectroscopic experiments. Polyketide synthase catalyzed putative biosynthetic mechanism additionally corroborated the structural ascriptions of the hitherto undescribed furanoterpenoids from seaweed-associated bacterial symbiont. The electronic and hydrophobic parameters appeared to hold a conspicuous part in directing the antibacterial properties of the compounds. Seaweed-associated B. subtilis MTCC 10403 demonstrated to represent a potential source of antimicrobial polyketides for pharmaceutical applications., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

A facile method based on gas chromatography-mass spectrometry (GC-MS) and molecular docking was established to analyze, identify, and predict lipase inhibitors in volatile oil from Pinus massoniana L. needles (PMLN). The volatile oil, with an IC 50 value of 15.25 ± 0.06 μg/mL, exhibited potential inhibitory activity against lipase in vitro. In total, 33 compounds were identified from the volatile oil through GC-MS analysis. The major compounds in the volatile oil were β-pinene (39.24%), α-pinene (14.68%), germacrene D (9.08%), caryophyllene (6.94%), α-terpineol (5.39%), β-phellandrene (4.82%), and D-limonene (3.93%). The identified compounds were individually docked with lipase as the target through molecular docking. Among the compounds, longifolene characterized by preferable binding energy and the good inhibition constant exhibited potential lipase inhibitory activity. The IC 50 value of longifolene was 25.10 ± 0.49 μM, indicating that this compound is the active ingredient responsible for the lipase inhibitory activity of PMLN volatile oil., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

S-limonene synthase is a model monoterpene synthase that cyclizes geranyl pyrophosphate (GPP) to form S-limonene. It is a relatively specific enzyme as the majority of its products are composed of limonene. In this study, we converted it to pinene or phellandrene synthases after introducing N345A/L423A/S454A or N345I mutations. Further studies on N345 suggest the polarity of this residue plays a critical role in limonene production by stabilizing the terpinyl cation intermediate. If it is mutated to a non-polar residue, further cyclization or hydride shifts occurs so the carbocation migrates towards the pyrophosphate, leading to the production of pinene or phellandrene. On the other hand, mutant enzymes that still possess a polar residue at this position produce limonene as the major product. N345 is not the only polar residue that may stabilize the terpinyl cation because it is not strictly conserved among limonene synthases across species and there are also several other polar residues in this area. These residues could form a "polar pocket" that may collectively play this stabilizing role. Our study provides important insights into the catalytic mechanism of limonene synthases. Furthermore, it also has wider implications on the evolution of terpene synthases., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Four meroterpenoids, 1-hydroxychevalone C, 1-acetoxychevalone C, 1,11-dihydroxychevalone C, and 11-hydroxychevalone C and two ester epimers, 2S,4S-spinosate and 2S,4R-spinosate, together with seven known compounds, chevalones B, C, and E, tryptoquivaline, nortryptoquivaline, tryptoquivaline L, and quinadoline A were isolated from the fungus Neosartorya spinosa. Their structures were established based on spectroscopic data analyses. The theoretical ECD spectra of epimers, 2S,4S-spinosate and 2S,4R-spinosate were calculated to support the experimental results of their CD spectra. 1-hydroxychevalone C exhibited antimycobacterial activity against Mycobacterium tuberculosis with a MIC value of 26.4 μM. 1-Acetoxychevalone C and tryptoquivaline showed antimalarial activity against Plasmodium falciparum with IC 50 values of 6.67 and 2.65 μM, respectively. In addition, 1-hydroxychevalone C, 1-acetoxychevalone C, 1,11-dihydroxychevalone C and quinadoline A showed cytotoxicity against KB and NCI-H187 cancer cell lines with IC 50 values in the range of 32.7-103.3 μM., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

The work herein presents comprehensive analyses of the cuticular wax mixtures covering the flag leaf blade and peduncle of bread wheat (Triticum aestivum) cv. Bethlehem. Overall, Gas Chromatography-Mass Spectrometry and Flame Ionization Detection revealed a wax coverage of flag leaf blades (16 μg/cm(2)) a third that of peduncles (49 μg/cm(2)). Flag leaf blade wax was dominated by 1-alkanols, while peduncle wax contained primarily β-diketone and hydroxy-β-diketones, thus suggesting differential regulation of the acyl reduction and β-diketone biosynthetic pathways in the two analyzed organs. The characteristic chain length distributions of the various wax compound classes are discussed in light of their individual biosynthetic pathways and biosynthetic relationships between classes. Along with previously reported wheat wax compound classes (fatty acids, 1-alkanols, 1-alkanol esters, aldehydes, alkanes, β-diketone, hydroxy-β-diketones, alkylresorcinols and methyl alkylresorcinols), esters of 2-alkanols and three types of aromatic esters (benzyl, phenethyl and p-hydroxyphenethyl) are also reported. In particular, 2-heptanol esters were identified. Detailed analyses of the isomer distributions within 1-alkanol and 2-alkanol ester homologs revealed distinct patterns of esterified acids and alcohols, suggesting several wax ester synthases with very different substrate preferences in both wheat organs. Terpenoids, including two terpenoid esters, were present only in peduncle wax., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

The defense of conifers against phytophagous insects relies to a large extent on induced chemical defenses. However, it is not clear how induced changes in chemical composition influence the meal properties of phytophagous insects (and thus damage rates). The defense can be induced experimentally with methyl jasmonate (MeJA), which is a substance that is produced naturally when a plant is attacked. Here we used MeJA to investigate how the volatile contents of Scots pine (Pinus sylvestris L.) tissues influence the meal properties of the pine weevil (Hylobius abietis (L.)). Phloem and needles (both weevil target tissues) from MeJA-treated and control seedlings were extracted by n-hexane and analyzed by two-dimensional gas chromatography-mass spectrometry (2D GC-MS). The feeding of pine weevils on MeJA-treated and control seedlings were video-recorded to determine meal properties. Multivariate statistical analyses showed that phloem and needle contents of MeJA-treated seedlings had different volatile compositions compared to control seedlings. Levels of the pine weevil attractant (+)-α-pinene were particularly high in phloem of control seedlings with feeding damage. The antifeedant substance 2-phenylethanol occurred at higher levels in the phloem of MeJA-treated than in control seedlings. Accordingly, pine weevils fed slower and had shorter meals on MeJA-seedlings. The chemical compositions of phloem and needle tissues were clearly different in control seedlings but not in the MeJA-treated seedlings. Consequently, meal durations of mixed meals, i.e. both needles and phloem, were longer than phloem meals on control seedlings, while meal durations on MeJA seedlings did not differ between these meal contents. The meal duration influences the risk of girdling and plant death. Thus our results suggest a mechanism by which MeJA treatment may protect conifer seedlings against pine weevils., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Four meroterpenoids [talarolutins A-D] and one known compound [purpurquinone A] were characterized from an endophytic fungal isolate of Talaromyces minioluteus (G413), which was obtained from the leaves of the medicinal plant milk thistle [Silybum marianum (L.) Gaertn. (Asteraceae)]. The structures of talarolutins A-D were determined by the analysis of various NMR and MS techniques. The relative and absolute configuration of talarolutin A was determined by X-ray diffraction analysis. A combination of NOESY data and comparisons of ECD spectra were employed to assign the relative and absolute configuration of the other analogs. Talarolutins B-D were tested for cytotoxicity against human prostate carcinoma (PC-3) cell line, antimicrobial activity, and induction of quinone reductase; no notable bioactivity was observed in any assay., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Giant fennel (Ferula communis L.) is well known in folk medicine for the treatment of various organ disorders. The biological importance of members of genus Ferula prompted us to investigate the leaves of the endangered Tunisian medicinal plant F. communis L. not previously investigated. An estimate of genetic diversity and differentiation between genotypes of breeding germplasm is of key importance for its improvement. Thus, four F. communis populations were RAPD fingerprinted (63 RAPD markers generated by 7 primers) and the composition of their leaf essential oils (EO) (134 EO compounds) was characterized by GC-MS. Cluster analysis based on the leaf volatiles chemical composition of F. communis accessions defined three chemotypes according to main compounds have been distinguished: α-eudesmol/β-eudesmol/γ-terpinene; α-eudesmol/α-pinene/caryophyllene oxide and chamazulene/α-humulene chemotypes. A high genetic diversity within population and high genetic differentiation among them, based on RAPDs, were revealed (H(pop)=0.320 and GST=0.288) caused both by the habitat fragmentation, the low size of most populations and the low level of gene flow among them. The RAPD dendrogram showed separation of three groups. Populations dominated by individuals from the β-eudesmol/γ-terpinene; chemotype showed the lowest gene diversity (H=0.104), while populations with exclusively α-pinene/caryophyllene oxide chemotype showed the highest value (H=0.285). The UPGMA dendrogram and PCA analysis based on volatiles yielded higher separation among populations, indicated specific adaptation of populations to the local environments. Correlation analysis showed a non-significant association between the distance matrices based on the genetic markers (RAPD) and chemical compounds of essential oil (P>0.05) indicating no influence of genetic background on the observed chemical profiles. These results reinforce the use of both volatile compounds and RAPD markers as a starting point for in situ conservation. The analysis of chemical constitution of oil of the populations from a specific region revealed predominance of specific constituents indicating possibility of their collection/selection for specific end uses like phytomedicines. Sufficient molecular and biochemical diversity detected among natural populations of this species will form the basis for the future improvement. The correlation between matrices of RAPD and essential oils was not significant. The conservation strategies of populations should be made according to their level of genetic and chemical diversity in relation to geographic location of populations. Our results give some insights into the characterization of this as yet little investigated plant., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Phytochemical investigation of the aerial parts of Chimonanthus salicifolius resulted in the isolation of two sesquiterpenoids, 8α-hydroxy-T-muurolol and (1α,6β,7β)-cadinane-4-en-8α,10α-diol, together with 13 known compounds. The 15 structures were established by means of 1D and 2D NMR spectroscopy. The relative and absolute configurations of 8α-hydroxy-T-muurolol and 8α,11-elemodiol were achieved by NOESY experiments and X-ray crystallography using CuKα radiation. 8α-hydroxy-T-muurolol and (1α,6β,7β)-cadinane-4-en-8α,10α-diol showed immunosuppressive activities in a dose-dependent manner., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

The aerial parts of Lippia integrifolia (incayuyo) are widely used in northwestern and central Argentina for their medicinal and aromatic properties. The essential oil composition of thirty-one wild populations of L. integrifolia covering most of its natural range was analyzed by GC and GC-MS. A total of one hundred and fifty two terpenoids were identified in the essential oils. Sesquiterpenoids were the dominant components in all but one of the collections analyzed, the only exception being a sample collected in San Juan province where monoterpenoids amounted to 51%. Five clearly defined chemotypes were observed. One possessed an exquisite and delicate sweet aroma with trans-davanone as dominant component (usually above 80%). Another with an exotic floral odour was rich in oxygenated sesquiterpenoids based on the rare lippifoliane and africanane skeletons. The trans-davanone chemotype is the first report of an essential oil containing that sesquiterpene ketone as the main constituent. The absolute configuration of trans-davanone from L. integrifolia was established as 6S, 7S, 10S, the enantiomer of trans-davanone from 'davana oil' (Artemisia pallens). Wild plants belonging to trans-davanone and lippifolienone chemotypes were propagated and cultivated in the same parcel of land in Santa Maria, Catamarca. The essential oil compositions of the cultivated plants were essentially identical to the original plants in the wild, indicating that the essential oil composition is largely under genetic control. Specimens collected near the Bolivian border that initially were identified as L. boliviana Rusby yielded an essential oil practically identical to the trans-davanone chemotype of L. integrifolia supporting the recent view that L. integrifolia (Gris.) Hieron. and L. boliviana Rusby are synonymous., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

The olive fly, Bactrocera oleae (Rossi), is a monophagous pest that displays an oviposition preference among cultivars of olive (Olea europaea L.). To clarify the oviposition preference, the olive leaf volatiles of three olive cultivars (Cobrançosa, Madural and Verdeal Transmontana) were assessed by headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC/MS) at six different periods of olive fruit maturation and degrees of infestation. A total of 39 volatiles were identified, mainly esters and alcohols, with a minor percentage of aldehydes, ketones and terpenic compounds, including sesquiterpenes. At sampling dates with higher degrees of infestation, cv. Cobrançosa had, simultaneously, significantly lower infestation degrees and higher volatile amounts than the other two cultivars, with a probable deterrent effect for oviposition. The green leaf volatiles (GLVs) (Z)-3-hexen-1-ol and (Z)-3-hexen-1-ol acetate) were the main compounds identified in all cultivars, together with toluene. The abundance of GLVs decreased significantly throughout maturation, without significant differences among cultivars, while toluene showed a general increase and positive correlation with olive fly infestation levels. The results obtained could broaden our understanding of the roles of various types and amounts of olive volatiles in the environment, especially in olive fly host selection and cultivar preference., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Topic applications of Calendula officinalis L. lipophilic extracts are used in phytotherapy to relieve skin inflammatory conditions whereas infusions are used as a remedy for gastric complaints. Such a different usage might be explained by some cytotoxicity of lipophilic extracts at gastric level but little is known about this. Therefore, we screened the CH2Cl2 extract from the flowers of C. officinalis by MTT and LDH assays in human epithelial gastric cells AGS. This bioassay-oriented approach led to the isolation of several sesquiterpene glycosides which were structurally characterized by spectroscopic measurements, chemical reactions and MM calculations. The conformational preferences of viridiflorol fucoside were established and a previously assigned stereochemistry was revised. The compounds 1a, 2a and 3f showed comparably high cytotoxicity in the MTT assays, whereas the effect on LDH release was lower. Our study provides new insights on the composition of C. officinalis extracts of medium polarity and identifies the main compounds that could be responsible for cytotoxic effects at gastric level., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Catasetum is a neotropical orchid genus that comprises about 160 dioecious species with a remarkable sexual dimorphism in floral morphology. Flowers of Catasetum produce perfumes as rewards, which are collected only by male euglossine bees. Currently, floral scents are known to be involved in the selective attraction of specific euglossine species. However, sexual dimorphism in floral scent and its eventual role in the pollination of Catasetum species have never been investigated. Here, we have investigated the pollination of Catasetum uncatum and asked: (1) Is floral scent a sexual dimorphic trait? (2) Does pollinarium removal/deposition affect scent emission? (3) Does sexual dimorphism in floral scent and changed scent emission have implications with regard to the behaviour of the pollinators? The frequency and behaviour of floral visitors were observed in non-manipulated flowers (both flower sexes) and in manipulated flowers (pistillate only) in which pollinaria were deposited. Scents of staminate and pistillate flowers (both manipulated and non-manipulated) were collected by using dynamic headspace methods and analysed chemically. Electrophysiological analyses were performed to detect compounds triggering antennal depolarisation in the euglossine species. C. uncatum is pollinated mainly by males of Euglossa nanomelanotricha. Pollinators were more frequent in pistillate than in staminate inflorescences. Bees approaching staminate flowers frequently flew away without visiting them, a behavioural pattern not observed in pistillate flowers. In the chemical analyses, we recorded 99 compounds, 31 of which triggered antennal depolarisation in pollinators. Multivariate analyses with the electrophysiological-active compounds did not detect differences between the scent composition of staminate and pistillate flowers. Pollinarium removal or deposition resulted in diminished scent emission within 24h in staminate and pistillate flowers, respectively. Surprisingly, bees discriminated pollinated from non-pollinated pistillate flowers as early as 2h after pollination. The rapid loss in the attractiveness of flowers following pollinarium removal/deposition can be interpreted as a strategy to direct pollinators to non-pollinated flowers. We have found no evidence that euglossine males discriminate staminate from pistillate flowers by means of floral scent. Instead, we speculate that bees use visual cues, such as sex dimorphic traits, to discriminate flowers of different sexes. Together, our results provide interesting insights into the evolution of floral signals in gender-dimorphic species and into its significance in plant reproductive biology., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Ganoderma lingzhi is a valuable, edible and medicinal fungus that has been widely used for the prevention and treatment of a broad range of diseases. In this study, spirolingzhines A-D, four meroterpenoids with a spiro[benzofuran-2,10-cyclopentane] motif, lingzhines A-F, six meroterpenoids with diverse ring systems, along with two known compounds were isolated from the fruiting bodies of this fungus. The structures and stereochemistry of these substances were determined by using spectroscopic, X-ray crystallographic and computational methods. Chiral HPLC was used to separate (-)- and (+)-antipodes of seven of ten meroterpenoids, which were isolated from the fungus as racemic mixtures. Several of the metabolites were found to promote proliferation of neural stem cells (NSCs) and, as such, they constitute a class of NSC stimulators. The most potent member of this series, (-)-spirolingzhine A, was shown to affect NSC cell cycle progression using the 5-bromo-2-deoxyuridine (BrdU) incorporation assay.

Aneura pinguis is one of the liverwort species complexes that consist of several cryptic species. Ten samples collected from different regions in Poland are in the focus of our research. Eight of the A. pinguis complex belonging to four cryptic species (A, B, C, E) and two samples of closely related species Aneura maxima were tested for the composition of volatile compounds. The HS-SPME technique coupled to GC/FID and GC/MS analysis has been applied. The fiber coated with DVB/CAR/PDMS has been used. The results of the present study, revealed the qualitative and quantitative differences in the composition of the volatile compounds between the studied species. Mainly they are from the group of sesquiterpenoids, oxygenated sesquiterpenoids and aliphatic hydrocarbons. The statistical methods (CA and PCA) showed that detected volatile compounds allow to distinguish cryptic species of A. pinguis. All examined cryptic species of the A. pinguis complex differ from A. maxima. Species A and E of A. pinguis, in CA and PCA, form separate clusters remote from two remaining cryptic species of A. pinguis (B and C) and A. maxima. Relationship between the cryptic species appeared from the chemical studies are in accordance with that revealed on the basis of DNA sequences., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Studies on the biosynthesis of oil compounds in Perilla will help in understanding regulatory systems of secondary metabolites and in elucidating reaction mechanisms for natural product synthesis. In this study, two types of alcohol dehydrogenases, an aldo-keto reductase (AKR) and a geraniol dehydrogenase (GeDH), which are thought to participate in the biosynthesis of perilla essential oil components, such as citral and perillaldehyde, were isolated from three pure lines of perilla. These enzymes shared high amino acid sequence identity within the genus Perilla, and were expressed regardless of oil type. The overall reaction from geranyl diphosphate to citral was performed in vitro using geraniol synthase and GeDH to form a large proportion of citral and relatively little geraniol as reaction products. The biosynthetic pathway from geranyl diphosphate to citral, the main compound of citral-type perilla essential oil, was established in this study., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Geraniol and linalool are acyclic monoterpenes found in plant essential oils that have attracted much attention for their commercial use and in pharmaceutical studies. They are synthesized from geranyl diphosphate (GDP) by geraniol and linalool synthases, respectively. Both synthases are very similar at the amino acid level and share the same substrate; however, the position of the GDP to which they introduce hydroxyl groups is different. In this study, the mechanisms underlying the regiospecific hydroxylation of geraniol and linalool synthases were investigated using a domain swapping approach and site-directed mutagenesis in perilla. Sequences of the synthases were divided into ten domains (domains I to IV-4), and each corresponding domain was exchanged between both enzymes. It was shown that different regions were important for the formation of geraniol and linalool, namely, domains IV-1 and -4 for geraniol, and domains III-b, III-d, and IV-4 for linalool. These results suggested that the conformation of carbocation intermediates and their electron localization were seemingly to be different between geraniol and linalool synthases. Further, five amino acids in domain IV-4 were apparently indispensable for the formation of geraniol and linalool. According to three-dimensional structural models of the synthases, these five residues seemed to be responsible for the different spatial arrangement of the amino acid at H524 in the case of geraniol synthase, while N526 is the corresponding residue in linalool synthase. These results suggested that the side-chains of these five amino acids, in combination with several relevant domains, localized the positive charge in the carbocation intermediate to determine the position of the introduced hydroxyl group., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Terpenoids are a large and diverse class of specialized metabolites that are essential for the growth and development of plants, and have tremendous industrial applications. The mericarps of Coriandrum sativum L. (coriander) produce an essential oil (EO) rich in monoterpenes, volatile C10 terpenoids. To investigate EO metabolism, the transcriptome of coriander mericarps, at three developmental stages (early, mid, late) was sequenced via Illumina technology and a transcript library was produced. To validate the usability of the transcriptome sequences, two terpene synthase candidate genes, CsγTRPS and CsLINS, encoding 558 and 562 amino acid proteins were expressed in bacteria, and the recombinant proteins purified by Ni-NTA affinity chromatography. The 65.16 (CsγTRPS) and 65.91 (CsLINS)kDa recombinant proteins catalyzed the conversion of geranyl diphosphate, the precursor to monoterpenes, to γ-terpinene and (S)-linalool, respectively, with apparent Vmax and Km values of 2.24±0.16 (CsγTRPS); 19.63±1.05 (CsLINS)pkat/mg and 66.25±13 (CsγTRPS); 2.5±0.6 (CsLINS)μM, respectively. Together, CsγTRPS and CsLINS account for the majority of EO constituents in coriander mericarps. Investigation of the coriander transcriptome, and knowledge gained from these experiments will facilitate future studies concerning essential and fatty acid oil production in coriander. They also enable efforts to improve the coriander oils through metabolic engineering or plant breeding., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

The goal of this study was to characterise the metabolic flux phenotype of transgenic tobacco (Nicotiana tabacum) hairy roots engineered for increased biosynthesis of geraniol, an intermediate of the terpenoid indole alkaloid pathway. Steady state, stable isotope labelling was used to determine flux maps of central carbon metabolism for transgenic lines over-expressing (i) plastid-targeted geraniol synthase (pGES) from Valeriana officinalis, and (ii) pGES in combination with plastid-targeted geranyl pyrophosphate synthase from Arabidopsis thaliana (pGES+pGPPS), as well as for wild type and control-vector-transformed roots. Fluxes were constrained by the redistribution of label from [1-¹³C]-, [2-¹³C]- or [¹³C6]glucose into amino acids, sugars and organic acids at isotopic steady state, and by biomass output fluxes determined from the fractionation of [U-¹⁴C]glucose into insoluble polymers. No significant differences in growth and biomass composition were observed between the lines. The pGES line accumulated significant amounts of geraniol/geraniol glycosides (151±24 ng/mg dry weight) and the de novo synthesis of geraniol in pGES was confirmed by ¹³C labelling analysis. The pGES+pGPPS also accumulated geraniol and geraniol glycosides, but to lower levels than the pGES line. Although there was a distinct impact of the transgenes at the level of geraniol synthesis, other network fluxes were unaffected, reflecting the capacity of central metabolism to meet the relatively modest demand for increased precursors in the transgenic lines. It is concluded that re-engineering of the terpenoid indole alkaloid pathway will only require simultaneous manipulation of the steps producing the pathway precursors that originate in central metabolism in tissues engineered to produce at least an order of magnitude more geraniol than has been achieved so far., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Seven terpenoids consisting of five sesquiterpenoids, hoaensieremone, hoaensieremodione, hoaensifuranonal, hoaensieudesone, and hoaensibenzofuranal, and two friedelane triterpenoids, 3α-(E)-p-coumaroyloxyfriedelan-7-one and 3α-(E)-caffeoyloxyfriedelan-7-one were isolated from the dichloromethane extract of the roots of Drypetes hoaensis. Additionally, twelve known compounds and vanillin were isolated. Their structures were established on the basis of spectroscopic analysis, as well as by comparison with literature data. The anticancer activity of nine of these compounds was investigated., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

In higher plants, both the methylerythritol phosphate (MEP) and mevalonate (MVA) pathways contribute to the biosynthesis of isoprenoids. However, despite a significant amount of research on the activity of these pathways under different conditions, the relative contribution of each to the biosynthesis of diverse isoprenoids remains unclear. In this work, we examined the formation of several classes of isoprenoids in cotton (Gossypium hirsutum L.). After feeding [5,5-(2)H2]-1-deoxy-D-xylulose ([5,5-(2)H2]DOX) and [2-(13)C]MVA to intact cotton seedlings hydroponically, incorporation into isoprenoids was analyzed by MS and NMR. The predominant pattern of incorporation followed the classical scheme in which C5 units from the MEP pathway were used to form monoterpenes (C10), phytol side chains (C20) and carotenoids (C40) while C5 units from the MVA pathway were used to form sesquiterpenes (C15), terpenoid aldehydes (C15 and C25) and steroids/triterpenoids (C30). However, both pathways contributed to all classes of terpenoids, sometimes substantially. For example, the MEP pathway provided up to 20% of the substrate for sterols and the MVA pathway provided as much as 50% of the substrate for phytol side chains and carotenoids. Incorporation of C5 units from the MEP pathway was highest in cotyledons, compared to true leaves, and not observed at all in the roots. Incorporation of C5 units from the MVA pathway was highest in the roots (into sterols) and more prominent in the first true leaves than in other above-ground organs. The relative accumulation of label in intermediates vs. end products of phytosterol metabolism confirmed previous identification of slow steps in this pathway., (Copyright © 2013. Published by Elsevier Ltd.)

Several species of the genus Urtica (especially Urtica dioica, Urticaceae), are used medicinally to treat a variety of ailments. To better understand the chemical diversity of the genus and to compare different accessions and different taxa of Urtica, 63 leaf samples representing a broad geographical, taxonomical and morphological diversity were evaluated under controlled conditions. A molecular phylogeny for all taxa investigated was prepared to compare phytochemical similarity with phylogenetic relatedness. Metabolites were analyzed via UPLC-PDA-MS and multivariate data analyses. In total, 43 metabolites were identified, with phenolic compounds and hydroxy fatty acids as the dominant substance groups. Principal component analysis (PCA) and hierarchical clustering analysis (HCA) provides a first structured chemotaxonomy of the genus. The molecular data present a highly resolved phylogeny with well-supported clades and subclades. U. dioica is retrieved as both para- and polyphyletic. European members of the U. dioica group and the North American subspecies share a rather similar metabolite profile and were largely retrieved as one, nearly exclusive cluster by metabolite data. This latter cluster also includes - remotely related - Urtica urens, which is pharmaceutically used in the same way as U. dioica. However, most highly supported phylogenetic clades were not retrieved in the metabolite cluster analyses. Overall, metabolite profiles indicate considerable phytochemical diversity in the genus, which largely falls into a group characterized by high contents of hydroxy fatty acids (e.g., most Andean-American taxa) and another group characterized by high contents of phenolic acids (especially the U. dioica-clade). Anti-inflammatory in vitro COX1 enzyme inhibition assays suggest that bioactivity may be predicted by gross metabolic profiling in Urtica., (Copyright © 2013. Published by Elsevier Ltd.)

Artemisia granatensis, an endemic endangered plant species from Sierra Nevada (Spain) has been successfully cultivated in artificial systems (plants in artificial soil and transformed in vitro roots) to generate enough plant biomass (aerial and root) to allow for its chemical and biological study and at the same time to provide with methods for the sustainable production of the plant and its metabolites. A eudesmanolide (17) along with six sesquiterpenes (11-16), nine monoterpenes (2-10), one nor-monoterpene (1), three acetylenic spiroacetal enoleters (18-20) and one coumarin (21) have been identified from the aerial plant ethanolic extract. Acetylenic spiroacetal enoleters 18-19 and coumarins 21-23 have been isolated from the transformed root ethanolic extract. These extracts and some isolated compounds or mixtures of them have been tested for their insect antifeedant effects against Spodoptera littoralis, Myzus persicae and Rhopalosiphum padi. Significant antifeedant properties were determined for the aerial plant extract, spiroacetals 19-20 and secoguaianolides 13+14 and 16., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

An 8,9-seco-lindenane disesquiterpenoid, chloramultiol G, four eudesmane sesquiterpenoids, ent-(3R)-3-hydroxyatractylenolide III and multistalactones A-C, and four guaiane sesquiterpenoids, (1R,4S,5R,8S,10S)-zedoalactone A and multistalactones D-F, along with 14 known compounds, were isolated from whole plant tissues of Chloranthus multistachys. Their structures were established by extensive NMR experiments in conjunction with mass spectrometry. Except for chloramultiol G, the absolute stereochemistries of the other eight were confirmed by single-crystal X-ray crystallography and CD spectra. Nine compounds were tested for cytotoxicity against five human tumor cell lines and for antifungal activity against four microorganisms in vitro, but all were inactive., (Copyright © 2012 Elsevier Ltd. All rights reserved.)