Diterpenoid Constituents Research Articles

Catalytic Antioxidant Activity of Two Diterpenoid Polyphenols of Rosemary, Carnosol, and Isorosmanol, against Lipid Oxidation in the Presence of Cysteine Thiol.

Lamiaceae herbs such as rosemary have excellent antioxidant properties, and lipidic diterpenoid constituents, such as carnosol, are known as characteristic components to exhibit strong antioxidant activity. This study investigates the effect of thiol compounds on the antioxidant properties of diterpenoid polyphenols. The results concerning the antioxidant activity of polyphenols in the presence of thiol showed that two polyphenols, namely, carnosol and isorosmanol, enhanced antioxidant capacity against the radical-induced oxidation of lipids. Further examination of the mechanism revealed that both polyphenols exhibit excellent catalytic antioxidant activity by using the thiol group as a reduction source. Using density functional theory calculations, we attempted to explain why only these two polyphenols exhibit catalytic antioxidant properties. The calculation results and the assumed reaction mechanism suggested that the orthoquinones produced in the antioxidant reactions of carnosol and isorosmanol are more unstable than the others and that the regioselectivity of their reactions with thiols contributes to their catalytic antioxidant properties.

Diterpenoid constituents in Pseudolarix amabilis and their antitumor activities in vitro

By various chromatographic techniques and extensive spectroscopic methods, 17 abietane diterpenoids were isolated from the dichloromethane fraction of the 95% ethanol cold-soak extracts of the seeds of Pseudolarix amabilis, namely pseudoamaol A(1), 12α-hydroxyabietic acid(2), 12-methoxy-7,13-abietadien-18-oic acid(3), 13-hydroxy-8,11,13-podocarpatrien-18-oic acid(4), 15-hydroxy-7,13-abietadien-12-on-18-oic acid(5), 8(14)-podocarpen-13-on-18-oic acid(6), holophyllin K(7), metaglyptin B(8), 7α-hydroxydehydroabietinsaure-methylester(9), 7-oxodehydroabietic acid(10), 15-hydroxy-7-oxodehydroabietinsaure-methy-lester(11), 15-methoxydidehydroabietic acid(12), 7-oxo-15-hydroxy-dehydroabietic acid(13), 15-hydroxydehydroabietic acid(14), 8,11,13-abietatriene-15,18-diol(15), 8,11,13-abietatriene-15-hydroxy-18-succinic acid(16), and 7β-hydroxydehydroabie-tic acid(17). Compound 1 was a new compound. The isolated compounds were evaluated for their antitumor activities(HepG2, SH-SY5Y, K562), and compounds 8 and 17 showed potential cytotoxic activity against K562 cells, with IC_(50) values of 26.77 and 37.35 μmol·L~(-1), respectively.

Diterpenoid Constituents of Psiadia punctulata and Evaluation of Their Antimicrobial Activity.

Sixteen diterpenes (1–16), along with 10 previously described compounds, including four flavonoids and six diterpenes, were isolated from the aerial parts of Psiadia punctulata growing in Saudi Arabia. The diterpene structures were elucidated using NMR spectroscopy and mass spectrometry data. Furthermore, a DFT/NMR procedure was used to suggest the relative configuration of several compounds. The labdane-derived skeletons, namely, ent-atisane, ent-beyerene, ent-trachylobane, and ent-kaurene, were identified. The extracts, fractions, and pure compounds were then tested against Staphylococcus aureus, Streptococcus mutans, Treponema denticola, and Lactobacillus plantarum. One diterpenoid, namely, psiadin, showed an additive effect with the antiseptic chlorhexidine, with a fractional inhibitory concentration index of less than 1. Additionally, psiadin showed a prospective inhibition activity for bacterial efflux pumps.

Macrocyclic Diterpenoid Constituents of Euphorbia deflexa, an Endemic Spurge from Greece.

Euphorbia deflexa, an endemic spurge from Greece, was investigated for the occurrence of its diterpene constituents. Through continuous monitoring by 1H NMR, 22 diterpenoids were isolated, including 16 previously undescribed compounds (euphodeflexins A-P), which belong to the jatrophane, ingenane, segetane, and pepluane diterpene types. Their chemical structures were elucidated through a combination of HRESIMS, NMR spectroscopy, and X-ray data. The isolated diterpenoids were tested against a panel of human cancer cell lines, as well as against two bacterial strains. Compounds 1, 13, and 17 were active against the HeLa cell line with IC50 values 9.9, 9.8, and 5.8 μM, respectively.

Prevalence of Diterpenes in Essential Oil of Euphorbia mauritanica L.: Detailed Chemical Profile, Antioxidant, Cytotoxic and Phytotoxic Activities.

Plants belonging to Euphorbia L. genus are considered very interesting from a medicinal point of view due to their diverse metabolites and bioactivities. The essential oil (EO) of Euphorbia mauritanica L. is not studied up to date. Therefore, the present study aimed to explore the chemical profile of this EO and evaluate its antioxidant, cytotoxic, and allelopathic potentialities. The EO was extracted from the whole plant via hydrodistillation and then, analyzed by gas chromatography/mass spectrometry (GC/MS). The correlation of E. mauritanica with the other Euphorbia plants was established using chemometric analysis. The antioxidant activity was determined based on scavenging of the free radical, 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS). The anti-proliferation of the EO on the Hep G2 and MCF-7 cells was evaluated. Finally the allelopathic activity of the EO was assessed against the two noxious weeds, Dactyloctenium aegyptium and Urospermum picroides. Forty-one compounds were identified using GC/MS analysis, with an abundance of terpenoids (91.54 %) that were categorized into mono- (30.75 %), sesqui- (15.23 %), and diterpenes (45.56 %). Interestingly, the results revealed the preponderance of diterpenoid constituents although they are rarely found in the EOs of the plant kingdom. The major compounds were (3E)-cembrene A (18.66 %), verticiol (17.05 %), limonene (7.91 %), eucalyptol (7.26 %), α-pinene (5.61 %), neo-cembrene A (3.52 %), kaur-16-ene (3.24 %), and cembrene (3.09 %). The EO showed moderate antioxidant activity where it attained IC50 values of 83.34 and 64.21 μg mL-1 for DPPH and ABTS compared to 23.01 and 19.23 μg mL-1 for ascorbic acid as standard, respectively. The EO exhibited very weak cytotoxic effect on MCF-7 and Hep G2 cells. The EO showed significant allelopathic activities against the weeds D. aegyptium and U. picroides in a concentration-dependent manner. EO was found more effective against U. picroides than D. aegyptium with IC50 values of 0.79, 0.45, and 0.67 mg mL-1 and 1.17, 0.55, and 1.08 mg mL-1 for germination, root, and shoot growth, respectively. Due to the high content of diterpenes in E. mauritanica, further study is recommended for more characterization of pure forms of the identified diterpenes as well as evaluating their bioactivity either solely or synergistically.

Qualitative and quantitative analysis of quassinoid diterpenoids from Eurycoma longifolia by UPLC-Q-TOF-MS combined with UPLC-QQQ-MS/MS

In this work, a sensitive and efficient method was established and validated for qualitative and quantitative analysis of major quassinoid diterpenoids constituents from the extract of Eurycoma longifolia by ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry(UPLC-Q-TOF-MS) and ultra-performance liquid chromatography coupled with a triple quadrupole mass spectrometry(UPLC-QQQ-MS/MS). The UPLC-Q-TOF-MS analysis was performed on an Agilent Eclipse Plus C_(18) RRHD(2.1 mm×100 mm,1.8 μm) column with acetonitrile and 0.1% formic acid water as mobile phase by gradient elution. The UPLC-QQQ-MS/MS analysis was performed on an Agilent Eclipse Plus C_(18) RRHD(2.1 mm×50 mm, 1.8 μm)column with acetonitrile and 0.1% formic acid water as mobile phase by gradient elution. The data was collected by electrospray ionization in positive mode. According to the contrast of the reference standards and the accurate masses of molecules, a total of 32 quassinoid diterpenoids in E. longifolia extract were identified by UPLC-Q-TOF-MS. For quantitative the linear range of 4 detected quassinoid diterpenoids were good(r≥0.999 6), and the overall recoveries ranged from 90.35% to 106.4%, with the RSD ranging from 1.8% to 3.6%. The method was accurate, reliable and efficient, and could comprehensively reflect the chemical constituents and content of E. longifolia, and could provide a reference for further elucidating its pharmacological basis and quality control.

Biological Activities of Two Major Copaiba Diterpenoids and Their Semi-synthetic Derivatives

The oleoresin of Copaifera reticulata Ducke, Fabaceae, is a traditional Brazilian remedy used for a wide range of applications. Commonly named copaiba, the oleoresin has been found to exhibit strong antimicrobial effects in our previous study, which could be attributed to some of its diterpenoid constituents. In order to find new biological activities and to eventually enhance the before observed effects, (−)-polyalthic acid (1) and kaurenoic acid (2), together with eight prepared semi-synthetic derivatives (1a–1c and 2a–2e) were evaluated for their cytotoxic, antibacterial and antifungal properties. Regarding the gram-positive bacteria Enterococcus faecium and methicillin-resistant Staphylococcus aureus, we found that both the exocylic methylene group and the carboxyl group were crucial for the activity against these two clinically relevant bacterial strains. Investigation of the antifungal activity, in contrast, showed that the carboxyl group is unnecessary for the effect against the dermatophytes Trichophyton rubrum and Cryptococcus neoformans, indicated by low micromolar IC50 values for both (−)-polyalthic acid diethylamide (1a) as well as (−)-polyalthic acid methyl ester (1b). Apart from studying the biological activity, the structure of one semi-synthetic derivative, compound 1c, is being reported for the first time. During the course of the structure elucidation of the new compound, we discovered inconsistencies regarding the stereochemistry of polyalthic acid and its stereoisomers, which we clarified in the present work.Graphical .

On the Use and Differentiation of Resins from Pinaceae Species in European Artworks Based on Written Sources, Reconstructions and Analysis

ABSTRACTIn recent decades, there have been more and more chemical analyses of aged and degraded lacquers, and the quality of identification of components has steadily improved. Despite this progress, a number of questions still remain open. This paper studied historical sources written in German in a bid to enhance and diversify the identification of natural resins in European lacquers, with special emphasis placed on resins of the Pinaceae family, which includes species of larch, fir, spruce and pine. The authors show that careful interpretation of the written sources, whilst unavoidable, enables important information on the composition of lacquers to be obtained. Chemical analysis of lacquers alone, without accompanying study of the sources, is problematic due to the considerable changes that occur in the resins during processing and ageing. Although the most important resins – mastic, larch turpentine and sandarac – can be easily identified, it was not possible to differentiate between fir, spruce and pine resins in aged lacquers. This can be explained by the properties of their diterpenoid constituents. Given that many commercial products are adulterated or even mislabelled to this day, it seems that discerning a product’s quality by evaluating colour, transparency and consistency, as described in the sources, is a method that is still very valuable today.

Antimicrobial and cytotoxic effects of the Copaifera reticulata oleoresin and its main diterpene acids

Ethnopharmacological relevanceThe oleoresin of Brazilian Copaifera reticulata is a traditional remedy used for the treatment of skin and urinary tract infections, respiratory diseases, rheumatism, ulcer and tumours; thus, playing an important role in the primary health care of the indigenous population. AimAs most previous pharmacological tests used the crude oleoresin and only a few studies so far dealt with enriched fractions or pure chemically defined compounds, the aim of this study was to systematically evaluate the antimicrobial and cytotoxic properties of the Copaifera reticulata oleoresin and to assign traditional uses to specific secondary metabolites. Materials and methodsThe oleoresin, as well as its neutral and acidic fractions were tested for their activity against six cancer cell lines, two clinically relevant bacterial strains, and two dermatophytes. Both fractions were analysed by GC-MS and UHPLC-ELSD, respectively. The antibacterial acidic phase was further fractionated by preparative chromatography to purify and characterize the compounds responsible for the observed pharmacological effect. ResultsWhereas no cytotoxic activity was detected, the crude oleoresin and its acidic fraction showed antibacterial activity against gram-positive bacteria Enterococcus faecium (IC50 values 4.2 and 4.8 µg/mL, respectively) and methicillin-resistant Staphylococcus aureus (MRSA, IC50 values 5.3 and 7.2 µg/mL, respectively). Purification of the acidic fraction of the C. reticulata oleoresin yielded two dicarboxylic diterpene acids and the four main diterpene acids, comprising three different diterpene scaffolds. Interestingly, the activity was not restricted to a particular diterpene-type but rather depended on the compounds’ lipophilicity, with the most active constituent showing IC50 values of 1.6 (E. faecium) and 2.5 µg/mL (MRSA), respectively. Furthermore, ent-polyalthic acid, the major diterpenoid, was significantly active against dermatophytes with IC50 values of 6.8 µg/mL (Trichophyton rubrum) and 4.3 µg/mL against (T. mentagrophytes). ConclusionThe present study proved the antimicrobial effects of the C. reticulata oleoresin and its diterpenoid constituents, confirming its wide use in folk medicine for the treatment of skin and urinary tract infections. The inhibitory activity of copaiba diterpenoids against dermatophytic fungi as well as the gram-positive bacteria E. faecium and MRSA is being reported for the first time, providing potential lead structures for the treatment of these clinically relevant bacterial strains.

Protective effect of andrographolides against docetaxel-induced cognitive impairment in rats bearing mammary tumours

Event Abstract Back to Event Protective effect of andrographolides against docetaxel-induced cognitive impairment in rats bearing mammary tumours Nasir I. Khatab1, Dahiru Sani1, Brian P. Kirby2, Norhafizah, Muhtarrudin1, Ho G. Fuang3, Johnson Stanslas1* and Hamidon Basri1* 1 Putra Malaysia University, Malaysia 2 Royal College of Surgeons in Ireland, Ireland 3 University Malaya Medical Centre, Malaysia Background Andrographolide (AGP) and 14-deoxy-11,12-didehydroandrographolide (DDAG) are two main diterpenoid constituents of Andrographis paniculata, which have shown several therapeutic effects. The aim of this study was to examine the protective effects of AGP and DDAG against cognitive impairment (CICI) caused by chemotherapeutic agent, docetaxel (DTX), on rats with mammary tumours. Methods A two-day Morris Water Maze (MWM) protocol, which involved training with a visible platform on day one followed by testing with a hidden platform on day two, was performed. Ten groups of female Sprague Dawley rats were used. The rats were injected with LA7 cells into the mammary gland pad to form tumours and further divided into groups of normal control (NC), cancer control (CC), treatment with DTX (single dose 5 mg/kg i.p.), three doses (0.25, 0.50 and 1.0 mg/kg) of AGP or DDAG and a vehicle. Subsequently, AGP, DDAG or vehicle was administered intraperitoneally for seven consecutive days followed by DTX injection after day one of visible platform trial. Levels of pro-inflammatory cytokine interleukin IL-1, lipid peroxidation marker (thiobarbituric acid-reactive substances (TBARS) and reactive oxygen species (ROS)) were measured. Results After 24 hours of DTX injection, the escape latency of DTX had significantly (p<0.001) increased to 58.1 sec compared to 24.7 sec in CC. AGP and DDAG significantly (p<0.001) reduced this DTX-induced latency to about 10-16 sec. AGP and DDAG significantly (p<0.001) reduced the elevated IL-1β (78-91%), IL-6 (55-75%), TNF-α (63-73%), TBARS (52-83%) and ROS (22-50%) levels when compared to DTX. AGP and DDAG did not affect the anti-cancer activity of DTX. Conclusion AGP and DDAG, if given prior to DTX, may be protective against the chemotherapy-induced cognitive impairment. Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 12 Acknowledgements The authors acknowledge the Ministry of Agriculture and Agro-Based Industry Malaysia for funding this research (NRGS Grants NH1014D025). Keywords: AGP, DDAG, DOCETAXEL, Morris water maze, cognitive impairment Conference: International Conference on Drug Discovery and Translational Medicine 2018 (ICDDTM '18) “Seizing Opportunities and Addressing Challenges of Precision Medicine”, Putrajaya, Malaysia, 3 Dec - 5 Feb, 2019. Presentation Type: Poster Presentation Topic: Neurodegenerative diseases Citation: Khatab NI, Sani D, Kirby BP, Muhtarrudin N, Fuang HG, Stanslas J and Basri H (2019). Protective effect of andrographolides against docetaxel-induced cognitive impairment in rats bearing mammary tumours. Front. Pharmacol. Conference Abstract: International Conference on Drug Discovery and Translational Medicine 2018 (ICDDTM '18) “Seizing Opportunities and Addressing Challenges of Precision Medicine”. doi: 10.3389/conf.fphar.2018.63.00134 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 12 Oct 2018; Published Online: 17 Jan 2019. * Correspondence: Prof. Johnson Stanslas, Putra Malaysia University, Seri Kembangan, Malaysia, jstanslas@yahoo.co.uk Prof. Hamidon Basri, Putra Malaysia University, Seri Kembangan, Malaysia, hamidonbasri@gmail.com Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Nasir I Khatab Dahiru Sani Brian P Kirby Norhafizah, Muhtarrudin Ho G Fuang Johnson Stanslas Hamidon Basri Google Nasir I Khatab Dahiru Sani Brian P Kirby Norhafizah, Muhtarrudin Ho G Fuang Johnson Stanslas Hamidon Basri Google Scholar Nasir I Khatab Dahiru Sani Brian P Kirby Norhafizah, Muhtarrudin Ho G Fuang Johnson Stanslas Hamidon Basri PubMed Nasir I Khatab Dahiru Sani Brian P Kirby Norhafizah, Muhtarrudin Ho G Fuang Johnson Stanslas Hamidon Basri Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

A semisynthetic diterpenoid lactone inhibits NF-κB signalling to ameliorate inflammation and airway hyperresponsiveness in a mouse asthma model

Andrographolide (AGP) and 14-deoxy-11,12-didehydroandrographolide (DDAG), two main diterpenoid constituents of Andrographis paniculata were previously shown to ameliorate asthmatic symptoms in a mouse model. However, due to inadequacies of both compounds in terms of drug-likeness, DDAG analogues were semisynthesised for assessment of their anti-asthma activity. A selected analogue, 3,19-diacetyl-14-deoxy-11,12-didehydroandrographolide (SRS27), was tested for inhibitory activity of NF-κB activation in TNF-α-induced A549 cells and was subsequently evaluated in a mouse model of ovalbumin (OVA)-induced asthma. Female BALB/c mice, 6–8weeks old were sensitized on days 0 and 14, and challenged on days 22, 23 and 24 with OVA. Compound or vehicle (3% dimethyl sulfoxide) was administered intraperitoneally 1h before and 11h after each OVA aerosol challenge. On day 25, pulmonary eosinophilia, airway hyperresponsiveness, mucus hypersecretion, inflammatory cytokines such as IL-4, -5 and -13 in BAL fluid, gene expression of inflammatory mediators such as 5-LOX, E-selectin, VCAM-1, CCL5, TNF-α, AMCase, Ym2, YKL-40, Muc5ac, CCL2 and iNOS in animal lung tissues, and serum IgE were determined. SRS27 at 30μM was found to suppress NF-κB nuclear translocation in A549 cells. In the ovalbumin-induced mouse asthma model, SRS27 at 3mg/kg displayed a substantial decrease in pulmonary eosinophilia, BAL fluid inflammatory cytokines level, serum IgE production, mucus hypersecretion and gene expression of inflammatory mediators in lung tissues. SRS27 is the first known DDAG analogue effective in ameliorating inflammation and airway hyperresponsiveness in the ovalbumin-induced mouse asthma model.

Qualitative and quantitative characterization of phenolic and diterpenoid constituents in Danshen (Salvia miltiorrhiza) by comprehensive two-dimensional liquid chromatography coupled with hybrid linear ion trap Orbitrap mass

Danshen is one of the most frequently used traditional Chinese herbs owing to its remarkable and reliable therapeutic effects. Phenolic acids and diterpenoids have proved to be the bioactive substance groups. In order to fully profile its chemical compositions and explore new potential bioactive compounds, a comprehensive two-dimensional liquid chromatography system coupled to DAD detector and hybrid linear ion trap (LTQ) Orbitrap mass spectrometry (LC×LC-DAD–ESI/HRMS/MSn) was set up in this study based on the column combination of Hypersil gold CN (150mm×1mm, 3μm) and Accucore C18 (50mm×4.6mm, 2.6μm). Using the optimal segment gradient program, phenolic acids and diterpenoids were separated into two independent groups and a total of 328 peaks were successfully detected on the contour plot of Danshen. By means of the accurate mass and reliable MSn data, 102 compounds were identified or tentatively identified and 7 of them were discovered from Danshen for the first time. Moreover, the LC×LC-DAD system was validated for the quantitative analysis of 14 bioactive analytes using the contour plot, exhibiting satisfactory linearity (r≥0.9976) and high precision for both peak locating (≤1.07%) and peak volume calculating (0.34%–4.11%). The established method could afford powerful separation capability, reliable identification data and accurate quantitative results, which is very suitable for analysis of complex herbal samples.

Isolation and Fast Selective Determination of Nor-abietanoid Diterpenoids from Perovskia atriplicifolia Roots Using LC-ESI-MS/MS with Multiple Reaction Monitoring

In the first part of this study we extracted, isolated, and identified the main diterpenoid constituents from the roots of a Central Asian medicinal and ornamental plant--Perovskia atriplicifolia Benth. Eight major nor-abietanoid pigments were obtained using NP silica gel column chromatography and preparative RP-HPLC: cryptotanshinone, 1-hydroxycryptotanhinone, miltirone, 1-oxomiltirone, tanshinone IIa, 1,2 didehydrotanshinone IIa, 1,2 didehydromiltirone, the non-quinone diterpenoid - arucadiol, as well as rosmarinic acid as a main phenolic compound. Secondly, we used the obtained compounds for fast and selective determination of the main diterpenes present in P. atriplicifolia root extract. After extraction with n-hexane, the quantitative analysis was carried out by LC-MS/MS with a triple quadrupole (qQq) mass detector without any prior clean-up step. Identification of the diterpenes was confirmed by multiple reaction monitoring (MRM) using the most representative transitions from the precursor ions, while the most sensitive transitions were used for quantification in a 19-minute run. Most of the isolated and analyzed compounds had not been previously reported from this species. This easily cultivated plant is a promising source of several pharmacologically valuable abietanoid diterpenoids.

Peroxisome proliferator-activated receptor transactivational effects in HepG2 cells of cembranoids from the soft coral Lobophytum crassum Von Marenzeller

Peroxisome proliferator-activated receptors (PPARs) are ligand-activated transcription factors that regulate the expression of multiple genes involved in metabolic, anti-inflammatory, and developmental processes. This study evaluated the PPARs transactivational effects of thirteen cembranoid diterpenoids 1-13 from the soft coral Lobophytum crassum, using PPAR-responsive elements-luciferase reporter and GAL4-PPAR chimera assays. All isolated compounds activated the transcription of PPARs in a dose-dependent manner, with EC50 values ranging from 2.07±1.73 to 130.20±1.85μM. Moreover, compounds 6-9 affected the transactivation of all three PPAR types, PPARα, γ, β(δ), in a dose-dependent manner, with EC50 values in a ranging from 11.92±1.23 to 122.50±2.12μM. These results provide a scientific rationale for further studies on the soft coral L. crassum and its diterpenoid constituents to develop medicinal products against inflammatory and metabolic diseases.

Pterodon pubescens Oil: Characterisation, Certification of Origin and Quality Control via Mass Spectrometry Fingerprinting Analysis

The oil obtained from Pterodon pubescens (Leguminosae) seeds are known to display anti-cancer, anti-dermatogenic and anti-nociceptive activitiy. Phytochemical studies have demonstrated that its main constituents are diterpenoids with voucapan skeletons. Considering the potential biological activities of the oil, rapid and efficient methods for assessing its quality would facilitate certification and quality control. To develop a direct mass spectrometric fingerprinting method for the P. pubescens seed oil that would focus on the major diterpenoids constituents, enabling quality control, origin certification and recognition of marker species in commercially available products. Two techniques were used: (i) direct infusion electrospray ionisation (ESI) mass spectrometry after solvent extraction and dilution and (ii) ambient desorption/ionisation via easy ambient sonic-spray ionisation, EASI(+)-MS, performed directly on the seed surface or at a paper surface imprinted with the oil. From a combination of ESI-MS, HRESI-MS and ESI-MS/MS data, 12 diterpenes were characterised, and typical profiles were obtained for the oil extract or the crude oil via both ESI-MS and EASI-MS. These techniques require no or very simple sample preparation protocols and the whole analytical processes with spectra acquisition take just a few minutes. Both techniques, but particularly EASI-MS, provide simple, fast and efficient MS fingerprinting methodologies to characterise the P. pubescens oil with typical (di)terpene profiles being applicable to quality control and certification of authenticity and origin.

Diterpenoid Constituents of the Roots of Salvia digitaloides

Salvia digitaloides, belonging to the economically and medicinally important genus Salvia, is distributed in the northwest of Yunnan Province, People's Republic of China. The roots of this plant were soaked in alcohol by local Tibetans to make a special traditional "red wine", and many local people like to drink this traditional "red wine" to strengthen physical health. To investigate the bioactive diterpenoid constituents of the roots, a detailed phytochemical study was carried out, and 13 diterpenoids including two new norditerpenoids, dihydroneotanshinlactone (1) and 16,17-dinorpisferal A (2), were isolated. Their structures were established on the basis of detailed spectroscopic analysis. In addition, computational methods were applied to validate the stereochemistry of compound 1. For the bioassay to inhibit the growth of five tumor cell lines, neotanshinlactone (3) exhibited selective cytotoxic activity toward the human breast cancer cell line SK-BR-3, while the other four tanshinones (4-7) showed significant toxicity effects against all of the tested five cell lines.

13C-NMR Data of Three Important Diterpenes Isolated from Euphorbia Species

Euphorbia species are widely distributed plants, many of which are used in folk medicine. Over the past twenty years, they have received considerable phytochemical and biological attention. Their diterpenoid constituents, especially those with abietane, tigliane, ingenane skeletons, are thought to be the main toxicant and bioactive factors. In this work, the utility of 13C-NMR spectroscopy for the structural elucidation of these compounds is briefly discussed.

Flavonoid glucosides from the leaves of &lt;i&gt;Croton tonkinensis&lt;/i&gt; Gagnep., Euphorbiaceae

Summary Two flavone C-glucosides vitexin (1) and isovitexin (2) were isolated as the major constituents with the total content of 59.5% of the methanol extract of the Croton tonkinensis leaves along with an minor acylated flavonol O-glucoside kaempferol 3-O-�D-(6’’-O-coumaroyl)glucopyranoside (tiliroside, 3) (0.9%). The structures of 1, 2 and 3 were determined on the basis of ESIMS, 1D and 2D NMR spectroscopic data. Although the flavonoid glucosides found exclusively in the ethyl acetate and n-butanol soluble fractions are reported for antioxidative and antiinflammatory activities their contribution to the medicinal properties of C. tonkinensis is demonstrated to be less than the lipid soluble entkaurene diterpenoid constituents of this plant.

Rapid separation and identification of phenolic and diterpenoid constituents from Radix Salvia miltiorrhizae by high‐performance liquid chromatography diode‐array detection, electrospray ionization time‐of‐flight mass spectrometry and electrospray ionization quadrupole ion trap mass spectrometry

High-performance liquid chromatography-diode array detection (HPLC-DAD), electrospray ionization time-of-flight mass spectrometry (HPLC-ESI-TOF-MS) and electrospray ionization quadrupole ion trap mass spectrometry (HPLC-ESI-MSn) were used for the isolation, identification and structural analysis of water-soluble phenolic and nonpolar diterpenoid constituents in Dan-shen (Radix Salvia miltiorrhizae) which was prepared by sonication in 70% methanol. Mass spectra were obtained by ESI-TOF-MS and electrospray ionization quadrupole ion trap mass spectrometry (ESI-QIT-MS). A formula database of known constituents in Dan-shen was established and most constituents were rapidly identified by HPLC-DAD/ESI-TOF-MS by matching their accurate molecular masses with the formulae of the compounds in the database. Compounds with the same molecular formula could not be differentiated by TOF-MS; however, QIT-MS could differentiate those compounds and elucidate their structures based on their characteristic fragmentation. HPLC-DAD, HPLC/ESI-TOF-MS and HPLC/ESI-MSn provided complementary information for the identification of the constituents in Dan-shen. Forty constituents were identified in 30 min based on their positive and negative ion ESI mass spectra and liquid chromatographic information. Thus the method described is useful for the rapid analysis of multiple constituents in Dan-shen.

Analysis of diterpenoic compounds in natural resins applied as binders in museum objects by capillary electrophoresis

The exudates of conifers consist mainly of diterpenoic acids of the abietane and pimarane type (abietic, neoabietic, dehydroabietic, palustric, pimaric, isopimaric, levopimaric and sandaracopimaric acid) and larixol acetate. These natural resins were used as adhesives, coatings, varnishes or plasticizers in artistic and historic works since ancient times. For the purpose of conservation and restoration and for art historic examination of such museum objects the identification of the binding media used is undoubtedly of paramount importance. In the present paper, the characterization of these resins based on the pattern of their diterpenoid constituents is carried out by capillary electrophoresis. For separation a background electrolyte which has been initially introduced for the analysis of chlorinated and natural resin acids in waste water was modified and the experimental conditions were adjusted in terms of resolution and analysis time. Separation was carried out in borate buffer at pH 9.25 (ionic strength 20 mmol L −1) with methyl-β-cyclodextrin and sulfobutylether-β-cyclodextrin as additives to increase selectivity and enhance the solubility of the analytes. With this electrophoretic system the resin acids of interest and larixol acetate – all as anionic cyclodextrin complexes – were separated within 5 min and detected at 200, 250 and 270 nm with a diode array detector. The electrophoretic patterns served for the characterisation of the relevant diterpenoic resins, balsams and copals. Sample pre-treatment was limited to sonication in methanol at 55 °C for 30 min. This enables the identification of the resins in mixtures with other binders like plant gums, animal glues or drying oils, even when these media are present in excess. Colophony was identified as resinous constituent of a modelling mass for gilded frames originating from the 19th century.