Five new eremophilane-type sesquiterpenes from the fresh roots of Rehmannia glutinosa.

Five undescribed eremophilane-type sesquiterpenes, remophilanetriols E-I (1-5), along with seven known compounds (6-12) were isolated from the fresh roots of Rehmannia glutinosa. Their structures were characterized by extensive spectroscopic data analysis and their absolute configurations were determined by comparing their calculated electronic circular dichroism (ECD) spectra and experimental ECD spectra. The anti-pulmonary fibrosis activities of all compounds were evaluated in vitro by MTT methods, and compounds 2, 8, 10, and 12 exhibited excellent anti-pulmonary fibrosis activities. In addition, compound 2 can reduce the levels of ROS and apoptosis in TGF-ß1-induced BEAS-2B cells.

New eremophilane-type sesquiterpenes from Synotis solidaginea.

Eleven new highly oxygenated eremophilane-type sesquiterpenoids were isolated from the whole plant of Synotis solidaginea, including two pairs of C-8 S/R epimers. The structures of the new compounds were elucidated on the basis of detailed spectroscopic analysis and the absolute configurations of 1 and 9 were confirmed by single-crystal X-ray crystallography using Cu Kα radiation. All the isolates were tested for the inhibition of LPS-stimulated NO production in macrophage-like mouse monocytic leukemia RAW264.7 cells. Compound 1 exhibited weak inhibitory effects with an IC50 of 71.2 µM.

Chemical Constituents of the Essential Oil from Ecuadorian Endemic Species Croton ferrugineus and Its Antimicrobial, Antioxidant and α-Glucosidase Inhibitory Activity.

Croton ferrugineus Kunth is an endemic species of Ecuador used in traditional medicine both for wound healing and as an antiseptic. In this study, fresh Croton ferrugineus leaves were collected and subjected to hydrodistillation for extraction of the essential oil. The chemical composition of the essential oil was determined by gas chromatography equipped with a flame ionization detector and gas chromatography coupled to a mass spectrometer using a non-polar and a polar chromatographic column. The antibacterial activity was assayed against three Gram-positive bacteria, one Gram-negative bacterium and one dermatophyte fungus. The radical scavenging properties of the essential oil was evaluated by means of DPPH and ABTS assays. The chemical analysis allowed us to identify thirty-five compounds representing more than 99.95% of the total composition. Aliphatic sesquiterpene hydrocarbon trans-caryophyllene was the main constituent with 20.47 ± 1.25%. Other main compounds were myrcene (11.47 ± 1.56%), ß-phellandrene (10.55 ± 0.02%), germacrene D (7.60 ± 0.60%), and α-humulene (5.49 ± 0.38%). The essential oil from Croton ferrugineus presented moderate activity against Candida albicans (ATCC 10231) with an MIC of 1000 µg/mL, a scavenging capacity SC50 of 901 ± 20 µg/mL with the ABTS method, and very strong antiglucosidase activity with an IC50 of 146 ± 20 µg/mL.

Six new cadinane-type sesquiterpenoids from the leaves of Chimonanthus nitens Oliv.

Six new cadinane-type sesquiterpenoids, named Chimnitensin A-F (1-6) were isolated from the leaves of Chimonanthus nitens Oliv. Their structures were elucidated by comprehensive spectroscopic analyses and comparison with structurally related known analogues. In vitro MTT assay showed that all six compounds had cytotoxicity against two selected human breast cancer cell lines (MDA-MB-468 and MDA-MB-231), which indicate their potential of developing into anticancer drugs.

Vernonia brasiliana (L.) Druce induces ultrastructural changes and apoptosis-like death of Leishmania infantum promastigotes.

The present study aimed to evaluate the antileishmanial effect, the mechanisms of action and the association with miltefosine of Vernonia brasiliana essential oil against Leishmania infantum promastigotes. This essential oil was obtained by hydrodistillation and its chemical composition was determined by gas chromatography-mass spectrometry (GC-MS). The antileishmanial activity against L. infantum promastigotes and cytotoxicity on DH82 cells were evaluated by MTT colorimetric assay. Ultrastructural alterations were evaluated by transmission electron microscopy. Changes in mitochondrial membrane potential, in the production of reactive oxygen species, and analysis of apoptotic events were determined by flow cytometry. The association between the essential oil and miltefosine was evaluated using the modified isobologram method. The most abundant component of the essential oil was ß-caryophyllene (21.47 %). Anti-Leishmania assays indicated an IC50 of 39.01 ±â€¯1.080 µg/mL for promastigote forms after 72 h of treatment. The cytotoxic concentration for DH82 cells was 63.13 ±â€¯1.211 µg/mL after 24 h of treatment. The effect against L. infantum was proven through the ultrastructural changes caused by the oil, such as kinetoplast and mitochondrial swelling, vesicles in the flagellar pocket, discontinuity of the nuclear membrane, nuclear fragmentation and condensation, and loss of organelles. It was observed that the oil leads to a decrease in the mitochondrial membrane potential (35.10 %, p = 0.0031), increased reactive oxygen species production, and cell death by late apoptosis (17.60 %, p = 0.020). The combination of the essential oil and miltefosine exhibited an antagonistic effect. This study evidences the antileishmanial action of V. brasiliana essential oil against L. infantum promastigotes.

Phytochemical study of Ligularia subspicata and valuation of its anti-inflammatory activity.

This report illustrated isolation and identification of 42 compounds comprising five (spicatainoids A-E) undescribed eremophilanolide type sesquiterpenoids and one undescribed nor-eremophilane (spicatainoid F) from Ligularia subspicata.. Among all the isolated new compounds, 4 is reported as the first enantiomeric form of novel eremophilanolide type sesquiterpenoid. Comprehensive analysis of HRESIMS, 1D/2D NMR, experimental circular dichroism (CD), calculated ECD analysis, and X-ray crystallographic (XRD) analysis validated the complete configuration and confirmation of these isolated compounds. All the isolated compounds were tested for the anti-inflammatory potential by measuring the amount of nitric oxide production. Among the tested compounds, 4 was the most effective with 90% NO-inhibition activity. Compounds 1, 2, 3, 9, 10 18, 29, 34, 35 exhibited moderate inhibitory effects against the production of NO, while other compounds displayed no activity even at the concentration of 50 µM. Additionally, compounds 1, 3 and 4 presented moderate anti-inflammatory activity by inhibiting the release of pro-inflammatory cytokines (TNF-α, IL-1ß, and IL-6) in LPS-stimulated N9 cells. The IC50 values of compounds 1, 3 and 4 were calculated 39.6 ± 2.7, 42.5 ± 3.8 and 27.60 ± 1.9 µΜ.

Origanum vulgare essential oil: antibacterial activities and synergistic effect with polymyxin B against multidrug-resistant Acinetobacter baumannii.

Antimicrobial resistance is increasing around the world and the search for effective treatment options, such as new antibiotics and combination therapy is urgently needed. The present study evaluates oregano essential oil (OEO) antibacterial activities against reference and multidrug-resistant clinical isolates of Acinetobacter baumannii (Ab-MDR). Additionally, the combination of the OEO and polymyxin B was evaluated against Ab-MDR. Ten clinical isolates were characterized at the species level through multiplex polymerase chain reaction (PCR) for the gyrB and blaOXA-51-like genes. The isolates were resistant to at least four different classes of antimicrobial agents, namely, aminoglycosides, cephems, carbapenems, and fluoroquinolones. All isolates were metallo-ß-lactamase (MßL) and carbapenemase producers. The major component of OEO was found to be carvacrol (71.0%) followed by ß-caryophyllene (4.0%), γ-terpinene (4.5%), p-cymene (3,5%), and thymol (3.0%). OEO showed antibacterial effect against all Ab-MDR tested, with minimum inhibitory concentrations (MIC) ranging from 1.75 to 3.50 mg mL-1. Flow cytometry demonstrated that the OEO causes destabilization and rupture of the bacterial cell membrane resulting in apoptosis of A. baumannii cells (p < 0.05). Synergic interaction between OEO and polymyxin B (FICI: 0.18 to 0.37) was observed, using a checkerboard assay. When combined, OEO presented until 16-fold reduction of the polymyxin B MIC. The results presented here indicate that the OEO used alone or in combination with polymyxin B in the treatment of Ab-MDR infections is promising. To the best of our knowledge, this is the first report of OEO and polymyxin B association against Ab-MDR clinical isolates.

Chemical characterization of Goniothalamus macrophyllus and Goniothalamus malayanus leaves' essential oils.

This study was aimed to investigate the chemical compositions of the essential oils from Goniothalamus macrophyllus and Goniothalamus malayanus growing in Malaysia. The essential oils were obtained by hydrodistillation and fully characterized by gas chromatography (GC-FID) and gas chromatography-mass spectrometry (GC-MS). Analyses of the essential oils from G. macrophyllus and G. malayanus resulted in 93.6 and 95.4% of the total oils, respectively. The major components of G. macrophyllus oil were germacrene D (25.1%), bicyclogermacrene (11.6%), α-copaene (6.9%) and δ-cadinene (6.4%), whereas in G. malayanus oil bicyclogermacrene (43.9%), germacrene D (21.1%) and ß-elemene (8.4%) were the most abundant components.

Anti-proliferative activity of A. Oxyphylla and its bioactive constituent nootkatone in colorectal cancer cells.

BACKGROUND: A. oxyphylla extract is known to possess a wide range of pharmacological activites. However, the molecular mechanism of A. oxyphylla and its bioactive compound nootkatone in colorectal cancer is unknown. METHODS: Our study aims to examine the role of A. oxyphylla and its bioactive compound nootkatone, in tumor suppression using several in vitro assays. RESULTS: Both A. oxyphylla extract and nootkatone exhibited antiproliferative activity in colorectal cancer cells. A. oxyphylla displayed antioxidant activity in colorectal cancer cells, likely mediated via induction of HO-1. Furthermore, expression of pro-apoptotic protein NAG-1 and cell proliferative protein cyclin D1 were increased and decreased respectively in the presence of A. oxyphylla. When examined for anticancer activity, nootkatone treatment resulted in the reduction of colony and spheroid formation. Correspondingly, nootkatone also led to increased NAG-1 expression and decreased cyclin D1 expression. The mechanism by which nootkatone suppresses cyclin D1 involves protein level regulation, whereas nootkatone increases NAG-1 expression at the transcriptional level. In addition to having PPARγ binding activity, nootkatone also increases EGR-1 expression which ultimately results in enhanced NAG-1 promoter activity. CONCLUSION: In summary, our findings suggest that nootkatone is an anti-tumorigenic compound harboring antiproliferative and pro-apoptotic activity.

Cadinane and carotane derivatives from the marine algicolous fungus Trichoderma virens RR-dl-6-8.

Eight cadinane derivatives, trichocadinins H - N (1-7) and methylhydroheptelidate (8), and two carotane derivatives, 14-O-methyltrichocarotin G (9) and 14-O-methyl CAF-603 (10), including eight new ones (1-6, 9, and 10), were isolated from the culture of Trichoderma virens RR-dl-6-8 obtained from the organohalogen-enriched marine red alga Rhodomela confervoides. Their structures and relative configurations were established by analysis of NMR and mass spectroscopic data, and the absolute configurations were assigned on the basis of ECD curves, highlighted by the ECD diversity of carboxylic acid derivatives. Among the isolates, 1 with a halogen atom and 8, a new naturally occurring compound, are 2,3-seco-cadinane sesquiterpenes, and the epimeric 2 and 3 feature a 2-nor-cadinane skeleton. A commercially-sourced compound with the same planar structure as that of 7 has been reported in a patent, but its configuration was not given. Compounds 1-10 exhibited growth inhibition of some marine phytoplankton species.

Anti-diabetic and lipid-lowering effects of drimane sesquiterpenoids isolated from Zygogynum pancheri.

Recently, it has been shown that drimane-type sesquiterpenoids isolated from Zygogynum pancheri, a species native to New Caledonia, possessed significant α-amylase inhibitory activities. To further explore their antidiabetic potential, we investigated the effect of 1ß-O-(E-cinnamoyl)-6α-hydroxy-9epi-polygodial (D) and 1ß-E-O-p-methoxycinnamoyl-bemadienolide (L), two of the most active compounds of the series, on diabetic model rats. Compounds D and L (2 mg kg/day) were daily and orally administrated for 30 days to streptozotocin (STZ) (150 mg/kg) induced male diabetic Wistar rats. Animals were allocated into five groups of six rats. Comparatively to diabetic rats, treatments with D and L compounds were able to significantly (P < 0.05) decrease Fasting Blood Glucose (FBG) (70.15%, 71.02%), serum total cholesterol (46.27% and 39.38%), triglycerides (56.60% and 58.15%), creatinine (37.31% and 36.49%) and uric acid levels (67.76% and 69.68%), respectively. Compounds D and L also restored the altered plasma enzyme (aspartate aminotransferase, AST (47.83% and 43.20%), alanine aminotransferase, ALT (49.76% and 48.35%, alkaline phosphatase, ALP (72.78% and 73.21%)) and lactate dehydrogenase, LDH (47.95% and 53.93%) levels to near normal, respectively. Administration of Glymepiride, significantly (p < 0.05) reduced FBG (73.94%) in STZ induced diabetic rats. Additionally, the compounds D and L exhibited inhibitory effects in vivo on lipase activity of diabetic rats (54.83% and 52.25%), respectively. The outcomes of this study suggested that these two drimanes could be considered as efficient hypoglycemic, hypolipidemic and antiobesity agents for diabetes management and its complications.

Trapping multiple dual mode liquid-liquid chromatography: Preparative separation of nootkatone from a natural product extract.

Trapping multiple dual mode (trapping MDM) is a preparative liquid-liquid chromatography (LLC) technique well-suited to difficult separations of intermediately-eluting components from similarly structured impurities. In this demonstrative study, a design approach for high process throughput is applied for the trapping MDM separation of a target component, nootkatone (NK), initially comprising 16.7% of an industrial side stream mixture with over 90 impurities. This design approach, previously developed and validated using ternary mixtures of model solutes, is applied to a complex real mixture for the first time. The approach consists of five steps: (1) determination of the maximum starting mixture concentration for feed preparation; (2) determination of the maximum flow rate for maintenance of the pre-set stationary phase fraction; (3) determination of the partition coefficients of the target and main impurities; (4) selection of step durations and number of cycles using an established short-cut method; (5) execution of the trapping MDM separation. The target, NK, was obtained along with a co-eluting component at 78.7% purity and 84.6% yield, demonstrating the effectiveness of trapping MDM for the separation of intermediately-eluting natural product target components from complex starting mixtures.

Characteristic Odor of the Japanese Liverwort (Leptolejeunea elliptica).

The volatile components produced by Leptolejeunea elliptica (Lejeuneaceae), which is a liverwort grown on the leaves of tea (Camellia sinensis), were collected and analyzed using headspace solid-phase microextraction-gas chromatography/mass spectrometry (HS-SPME-GC/MS). 1-Ethyl-4-methoxybenzene (1), 1-ethyl-4-hydroxybenzene (2), and 1-acetoxy-4-ethylbenzene (3) were identified as the major components together with several other phenolic compounds, including 1,2-dimethoxy-4-ethylbenzene, and 4-ethylguaiacol in addition to sesquiterpene hydrocarbons, such as α-selinene, ß-selinene, ß-elemene, and ß-caryophyllene. GC/Olfactometry showed the presence of linalool, acetic acid, isovaleric acid, trans-methyl cinnamate, and trans-4,5-epoxy-(2E)-decenal, as the volatile components produced by L. elliptica.

Variations in compositions and antioxidant activities of essential oils from leaves of Luodian Blumea balsamifera from different harvest times in China.

Xanthoxylin was the main compound (content 44.92% of total volatiles) in the leaves of Luodian B. balsamifera, which might be the key cause of failure in collecting essential oil (EO) of the leaves using general hydrodistillation in Clevenger apparatus. A modified hydrodistillation equipped with Clevenger apparatus was designed for isolating EO from the leaves. Six EOs of Luodian B. balsamifera harvested once a month from September to next February were collected successfully. The main components of EOs were δ-elemene, α-cubenene, caryophyllene, caryophyllene epoxide, γ-eudesmol, xanthoxylin, and α-eudesmol. The EOs of Luodian B. balsamifera collected from October to December had higher antioxidant activities (ACs). Combining the principal component analysis of chemical components with the results of ACs and the yields of six EOs, the leaves of Luodian B. balsamifera were suitable to be harvested in November and December to obtain EO with high quality.

Identification of the Volatile Components of Galium verum L. and Cruciata leavipes Opiz from the Western Italian Alps.

The chemical composition of the volatile fraction from Galium verum L. (leaves and flowers) and Cruciata laevipes Opiz (whole plant), Rubiaceae, was investigated. Samples from these two plant species were collected at full bloom in Val di Susa (Western Alps, Turin, Italy), distilled in a Clevenger-type apparatus, and analyzed by GC/FID and GC/MS. A total of more than 70 compounds were identified, making up 92%-98% of the total oil. Chemical investigation of their essential oils indicated a quite different composition between G. verum and C. laevipes, both in terms of the major constituents and the dominant chemical classes of the specialized metabolites. The most abundant compounds identified in the essential oils from G. verum were 2-methylbenzaldheyde (26.27%, corresponding to 11.59 µg/g of fresh plant material) in the leaves and germacrene D (27.70%; 61.63 µg/g) in the flowers. C. laevipes essential oils were instead characterized by two sesquiterpenes, namely ß-caryophyllene (19.90%; 15.68 µg/g) and trans-muurola-4(15),5-diene (7.60%; 5.99 µg/g); two phenylpropanoids, benzyl alcohol (8.30%; 6.71 µg/g), and phenylacetaldehyde (7.74%; 6.26 µg/g); and the green-leaf alcohol cis-3-hexen-1-ol (9.69%; 7.84 µg/g). The ecological significance of the presence of such compounds is discussed.

Caryophyllene-type sesquiterpenoids and α-furanones from the plant endophytic fungus Pestalotiopsis theae.

Two new caryophyllene-type sesquiterpenoids, pestathenols A (1) and B (2) and one new α-furanone, pestatheranone A (6), along with five known compounds (3-5, 7 and 8) have been isolated from the crude extract of the plant endophytic fungus Pestalotiopsis theae. Their structures were unambiguously established by extensive spectroscopic analyses. The absolute configuration of the 5,6-diol moiety in 1 was assigned using Snatzke's method. Compounds 1 and 2 showed weak cytotoxicity against HeLa cell line.

Cadinane-type sesquiterpenes from the resinous exudates of Commiphora myrrha and their anti-Alzheimer's disease bioactivities.

Commiphoins A-C (1-3), three new cadinane-type sesquiterpenes, together with two known cadinane-type sesquiterpenes (4 and 5) were isolated from the resinous exudates of Commiphora myrrha. Their structures and relative configurations were established on the basis of comprehensive spectroscopic methods, including HRESIMS, 1D and 2D NMR analyses. Compounds 1 and 3-5 were screened for anti-Alzheimer's disease (AD) activities using the AD pathological model in Caenorhabditis elegans. The results showed that they all had significant anti-AD activities.

Himachalol induces apoptosis in B16-F10 murine melanoma cells and protects against skin carcinogenesis.

ETHNOPHARMACOLOGICAL RELEVANCE: Cedrus libani A. Rich (C. libani) is majestic evergreen Mediterranean conifer growing in the mountains of Lebanon. The ethnobotanical and traditional uses of cedar wood oil traces back to ancient times for the treatment of various ailments including cancer. Previous work in our laboratories revealed that himachalol (7-HC), a major sesquiterpene isolated from C. libani, possesses potent cytotoxic activity against various human cancer cell lines as well as promising anti-inflammatory effect in isolated rat monocytes. AIM OF THE STUDY: The present study aims to elucidate the mechanism of action behind the cytotoxic activity of 7-HC against murine melanoma cells (B16F-10) and evaluates its chemopreventive effect against chemically-induced skin carcinogenesis in mice. MATERIALS AND METHODS: 7-HC was extracted and purified from Cedrus libani wood. Cell viability was evaluated using WST-1 kit. Cell cycle analysis and apoptosis were assessed by Flow cytometry using propidium iodide (PI) and fluorescein Isothiocyanate (FITC)-conjugated Annexin V/PI staining respectively. Apoptosis related protein were quantified using western blot. The chemopreventive activity of 7-HC was evaluated for 20 weeks using a DMBA/TPA induced skin carcinogenesis model in Balb/c mice. RESULTS: 7-HC displayed a potent anti-proliferative activity against the melanoma cells with an IC50 of 8.8 µg/ml and 7.3 µg/ml at 24 and 48 h, respectively. Co-treatment with Cisplatin did not show any synergistic or additive effect on cell viability. Flow cytometry analysis using PI revealed that 7-HC treatment (5 and 10 µg/ml) induces the accumulation of cells in the sub-G1 phase and causes a decline in cell populations in the S and G2/M phases. Annexin/PI staining also reveals that 7-HC treatment significantly increases the percentage of cells undergoing early and late apoptosis. Western blot analysis shows that 7-HC treatment decreases the level of the anti-apoptotic protein Bcl-2 and increases the level of the pro-apoptotic protein Bax. A reduction in the level of phosphorylated Erk and Akt was also observed. 7-HC via topical (2.5%), intraperitoneal (10, 25 and 50 mg/kg) or gavage (50 mg/kg) treatment revealed a significant decrease in papilloma volume with no adverse effect on liver and kidney function. CONCLUSIONS: The present study demonstrates that 7-HC treatment protects against chemically-induced skin carcinogenesis, promotes cell cycle arrest and induces apoptosis partially through an inhibition of both the MAPK/Erk and PI3K/Akt pathways.

New cadinane sesquiterpenoids from Mikania micrantha.

Chemical investigation of the aerial parts of Mikania micrantha led to the isolation of eight sesquiterpenoids and ten diterpenoids, including five cadinane sesquiterpenoids (1-5), three bisabolene sesquiterpenoids (6 - 8), nine ent-kaurane diterpenoids (9-17), and an abietane diterpenoid (18). Among them, 1 - 3 are new and feature a rare lactone or furan ring derived from C-6 isopropyl group side chain. Compound 18 was isolated from genus Mikania for the first time, and was also the first example of abietane-type diterpenoids from this plant. Their structures were elucidated on the basis of extensive spectroscopic analyses (1D and 2D NMR, HRESIMS, and ECD). All compounds were examined for their inhibitory effects on lipopolysaccharide (LPS)-induced nitric oxide (NO) production in RAW 264.7 macrophage cells, and compound 18 exhibited pronounced inhibition on NO production (IC50 = 11.04 µM), being comparable to the positive control, quercetin (IC50 = 11.15 µM).