Sesquiterpenes fromSyneilesis palmata and their cytotoxicity against human cancer cell linesin vitro

Phytochemical Investigation of Equisetum arvense and Evaluation of Their Anti-Inflammatory Potential in TNFα/INFγ-Stimulated Keratinocytes

Equisetum arvense L. (Equisetaceae), widely known as 'horsetail', is a perennial plant found extensively across Asia. Extracts of E. arvense have been used in traditional medicine, particularly for the treatment of inflammatory disorders. This study aimed to determine the phytochemical compounds in E. arvense ethanolic extract and their anti-inflammatory properties. Subsequently, we isolated and identified nine secondary metabolites, including kaempferol 3,7-di-O-β-D-glucopyranoside (1), icariside B2 (2), (Z)-3-hexenyl β-D-glucopyranoside (3), luteolin 5-O-β-D-glucopyranoside (4), 4-O-β-D-glucopyranosyl caffeic acid (5), clemastanin B (6), 4-O-caffeoylshikimic acid (7), (7S,8S)-threo-7,9,9'-trihydroxy-3,3'-dimethoxy-8-O-4'-neolignan-4-O-β-D-glucopyranoside (8), and 3-O-caffeoylshikimic acid (9). The chemical structures of the isolated compounds (1-9) were elucidated using HR-ESI-MS data, NMR spectra, and ECD data. Next, the anti-inflammatory effects of the isolates were evaluated in tumor necrosis factor (TNF)α/interferon (IFN)γ-induced HaCaT, a human keratinocyte cell line. Among the isolates, compound 3 showed the highest inhibitory effect on the expression of pro-inflammatory chemokines, followed by compounds 6 and 8. Correspondingly, the preceding isolates inhibited TNFα/IFNγ-induced activation of pro-inflammatory transcription factors, signal transducer and activator of transcription 1, and nuclear factor-κB. Collectively, E. arvense could be employed for the development of prophylactic or therapeutic agents for improving dermatitis.

Anti-inflammatory norclerodane diterpenoids and tetrahydrophenanthrene from the leaves and stems of Dioscorea bulbifera

Chemical investigation of the leaves and stems of Dioscorea bulbifera resulted in isolation of 10 compounds, including three new norclerodane diterpenoids, diosbulbiferins A (1) and B (2) and diosbulbiferinoside A (3), and one new natural congener, diosbulbiferin C (4), along with one new tetrahydrophenanthrene, diosbulbinone (8). Their structures were elucidated by comprehensive analyses of spectroscopic methods, including NMR and mass spectra. The absolute configurations of compounds 1-3 and 8 were deduced by time-dependent density functional theory (TD-DFT) electronic circular dichroism (ECD) spectroscopic analyses. In addition, cytotoxic effects against MCF-7, HepG2, and SK-Mel-2 cancer cells and in vitro anti-inflammatory effects of the isolated compounds in LPS-stimulated BV2 microglial cells were also reported.

Garcinoic Acids and a Benzophenone Derivative from the Seeds of Garcinia kola and Their Antibacterial Activities against Oral Bacterial Pathogenic Organisms

In this study, three new garcinoic acid dimers, δ,δ-bigarcinoic acid (1), δ,δ-bi-O-garcinoic acid (2), and γ,δ-bi-O-garcinoic acid (3), and a new benzophenone derivative, (8E)-4-geranyl-3,5-dihydroxybenzophenone (4), as well as seven known compounds (5-11) were isolated from the seeds of Garcinia kola. The structures of the new compounds were elucidated using MALDI-TOF-MS and spectroscopic data, including 1D and 2D NMR and electronic circular dichroism spectra. All of the isolated compounds were evaluated for their antimicrobial activity against two oral pathogens, Porphyromonas gingivalis and Streptococcus sobrinus. Among them, 4 and δ-garcinoic acid (6) exhibited antimicrobial activity against both of these microorganisms (MICs of 31.3-62.5 μM for P. gingivalis and 15.6-31.3 μM for S. sobrinus). These results indicate that some chemical constituents in G. kola seeds have potential application in the prevention of oral diseases.

Sesquiterpene Lactones and Flavonoids from Psephellus pyrrhoblepharus with Antiproliferative Activity on Human Gynecological Cancer Cell Lines

Multistep chromatographic separations of the chloroform extract of the Turkish endemic plant Psephellus pyrrhoblepharus (Boiss.) Wagenitz (syn. Centaurea pyrrhoblephara Boiss.) resulted in the isolation of six guaianolid-type sesquiterpenes, chlorojanerin (1), 19-deoxychlorojanerin (2), 15-hydroxyjanerin (3), aguerin B (4), cynaropicrin (5), eleganin (6); three flavonoids, apigenin, 6-methoxyluteolin and jaceosidine; two glycosides, benzyl-1-O-β-d-glucoside and 3(Z)-hexenyl-1-O-β-d-glucoside; and the coumarin scopoletin. The structures were established by the interpretation of their ESI-MS and 1D and 2D NMR data including ¹H-NMR, JMOD, ¹H,¹H-COSY, HSQC, HMBC, and NOESY experiments. All compounds were isolated for the first time from P. pyrrhoblepharus. Compounds 1-6, the isolated flavonoids and scopoletin were evaluated for their antiproliferative activities on human gynecological cancer cell lines (SiHa, HeLa, and MDA-MB-231 cells) using the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. Chlorojanerin (1), 19-deoxychlorojanerin (2), aguerin B (4), cynaropicrin (5), eleganin (6) were shown to have noteworthy effects on all of the tested cell lines, while apigenin, jaceosidine, and 6-methoxyluteolin were moderately active on HeLa cells. The highest activities were demonstrated by the chlorine-containing derivatives chlorojanerin (1) and 19-deoxychlorojanerin (2) with IC₅₀ values of 2.21 and 2.88 µM, respectively, against the triple negative breast cancer model MDA-MB-231 cells.

Phytochemical study of Piliostigma thonningii, a medicinal plant grown in Nigeria

Piliostigma thonningii (Schumach.) Milne-Redhead. (Leguminosae) is used for various medicinal purposes in African countries. Phytochemical investigation of P. thonningii yielded two compounds newly isolated from natural sources, 2β-methoxyclovan-9α-ol (1), and methyl-ent-3β-hydroxylabd-8(17)-en-15-oate (2), along with 14 known compounds (3-16). Compounds 1 and 4 (alepterolic acid) showed potential selectivity towards Trypanosoma brucei brucei with IC50 7.89 and 3.42 μM, respectively. Compound 2 showed activity towards T. brucei and Leishmania donovani Amastigote with IC50 3.84 and 7.82 μM, respectively. The structure activity relationship (SAR) of the isolated metabolites suggested that hydroxylation at C-2 enhances the antiprotozoal activity towards T. brucei in sesquiterpenes 1 and 3. Similarly hydroxylation at C-3 in labdane diterpenes elevates the antiprotozoal activity towards T. brucei.

Chemical Composition of Essential Oils from Zanthoxylum bungeanum Maxim. and Their Bioactivities against Lasioderma serricorne

Two essential oil samples were obtained from the pericarp of Zanthoxylum bungeanum with the methods of hydrodistillation (HD) and supercritical fluid CO₂ extraction (SFE), their chemical components were identified, and their bioactivities against Lasioderma serricorne adults were evaluated. In the process of testing, the two samples showed significant bioactivities against Lasioderma serricorne adults. For an example, the SFE-sample expressed relatively stronger fumigant toxicity on Lasioderma serricorne adults (LC₅₀ = 3.99 μg/mL air) than that of the HD-sample (LC₅₀ = 12.54 μg/mL air). According to GC-MS analysis, the chemical components between two samples were different. The major chemical components for HD included linalool (25.99%), limonene (19.34%), linalyl anthranilate (12.22%), 4-terpinenol (10.49%), eucalyptol (6.53%) and α-terpineol (5.02%), while for SFE included nonanoic acid (21.43%), γ-terpinene (14.51%), eucalyptol (13.45%), α-terpineol (5.83%) and caryophyllene oxide (5.48%). The results showed that different chemical components result in different bioactivities. This work provides theoretical basis for traditional Chinese concept of antagonistic storage, and it also provides important information for the development and comprehensive utilization of Zanthoxylum bungeanum.

Identification of chemical constituents of Zanthoxylum heitzii stem bark and their insecticidal activity against the malaria mosquito Anopheles gambiae

Background

Zanthoxylum heitzii bark extracts have insecticidal properties and have been reported to be used against malaria in Western Africa. Previously, it has been shown that a hexane extract of the bark is toxic to adult females of the mosquito Anopheles gambiae, a malaria vector. As part of our project on the control of malaria vectors using plant extracts, the phytochemistry of Z. heitzii bark hexane extract has been investigated with the aim to identify the major components with adulticidal and larvicidal effects on An. gambiae.

Methods

Z. heitzii stem bark was extracted with hexane, and the extract was fractionated to isolate major components from the bark, identified by NMR spectroscopy. Isolated compounds were tested for toxicity towards adult female An. gambiae mosquitoes and for larvicidal effects towards An. gambiae.

Results

The alkaloid dihydronitidine, the sesquiterpenoid caryophyllene oxide, the amide pellitorine and the lignan sesamin were identified as the major constituents in Z. heitzii bark. Pellitorine was toxic to both adult insects (LD₅₀ 50 ng/mg insect) and larvae (LD₅₀ 13 μg/ml). None of the other compounds were toxic to adults, but caryophyllene oxide and sesamin exhibited moderate larvicidal effects (LD₅₀ > 150 μg/ml). A mixture of the four compounds in the same ratio as in the hexane extract showed higher toxicity (LD₅₀ 34 ng/mg insect) towards adult insects than the pure compounds.

Conclusion

The toxicity of Z. heitzii bark hexane extract to An. gambiae is mostly due to pellitorine, although interactions between pellitorine and other, inactive constituents may enhance the activity of the extract.

Chemical Constituents and Activity of Murraya microphylla Essential Oil against Lasioderma serricorne

The chemical composition, contact and repellent activities of the essential oil from Murraya microphylla branches and leaves against Lasioderma serricorne adults were determined and six compounds from the essential oil were isolated as well. The essential oil of M. microphylla obtained by hydrodistillation was analyzed by gas chromatography-mass spectrometric (GC-MS) analysis; 22 compounds were identified. The main constituents of the essential oil included β-caryophyllene (18.0%), α-pinene (13.8%), spathulenol (9.5%), α-humulene (6.0%), γ-elemene (5.1%) and zingiberene (4.6%), followed by α-cadinol (3.9%) and caryophyllene oxide (3.8%). Six of these compounds were isolated and fully identified as α-pinene, β-caryophyllene, α-humulene, caryophyllene oxide, spathulenol and α-cadinol. L. serricorne adults had different sensitivities to the crude essential oil and isolated compounds. α-Humulene exhibited the strongest contact activity against L. serricorne, showing an LD50 value of 13.1 μg adult−1. However, spathulenol, the crude essential oil and α-cadinol showed stronger contact activity against L. serricorne than caryophyllene oxide and β-caryophyllene. The essential oil, α-humulene and spathulenol showed comparable repellency against L. serricorne adults at 2 h after exposure, relative to the positive control, DEET. The results demonstrate that the essential oil and isolated compounds exhibited important contact and repellent activities against L. serricorne. Thus, they could become potential natural insecticides or repellents for control of insects in stored products.

Syneilesis palmata (Thunb.) Maxim. extract attenuates inflammatory responses via the regulation of TRIF-dependent signaling and inflammasome activation

ETHNOPHARMACOLOGICAL RELEVANCE

Syneilesis palmata (Thunb.) Maxim. (S. palmata, Asteraceae) is a traditional Korean therapeutic herb widely used to treat pain, arthritis, and other symptoms. This study provides the scientific basis for the anti-inflammatory effects of S. palmata extract (SP) in both in vitro and in vivo experimental models.

MATERIALS AND METHODS

Lipopolysaccharide (LPS)-stimulated murine macrophages were used to study the regulatory effect of SP on the inflammatory mediators in vitro. Bone marrow-derived macrophages were used to study the effects of SP on inflammasome activation. Escherichia coli-induced sepsis mouse model and LPS-induced endotoxin shock model were employed to study the effect of SP on in vivo efficacy.

RESULTS

SP inhibited the LPS-stimulated release of proinflammatory mediators, such as nitric oxide and interleukin (IL)-6 in RAW 264.7 cells. SP treatment also attenuated IL-1β secretion via the inhibition of NLRP3 inflammasome activation induced by monosodium urate, ATP, and nigericin. Further, SP ameliorated the severity of NLRP3 inflammasome-mediated symptoms in LPS-induced endotoxin and E. coli-induced sepsis mouse models. Mechanistic studies revealed that inhibitory effects of SP were mediated through the regulation of TRIF-dependent signaling and inflammasome activation.

CONCLUSION

This study was the first to reveal mechanistic-based evidence substantiating the traditional claims of SP in the treatment of inflammation-related disorders, such as pain and arthritis.

Senecio scandens Buch.-Ham.: a review on its ethnopharmacology, phytochemistry, pharmacology, and toxicity

ETHNOPHARMACOLOGICAL RELEVANCE

The aerial parts of Senecio scandens Buch.-Ham. (family Asteraceae) have a long history in traditional Chinese medicine as a treatment for various ailments, such as bacterial diarrhea, enteritis, conjunctivitis, and respiratory tract infections.

MATERIALS AND METHODS

A bibliographic investigation of Senecio scandens was accomplished by analyzing secondary sources, including the Chinese Medicinal plantal Classics, the Internet (Google Scholar and Baidu Scholar), and scientific databases accepted worldwide (Pubmed, Scopus, Web of Science, SciFinder, and CNKI). These sources were scrutinized for available information about the uses of Senecio scandens in traditional Chinese medicine, phytochemistry, pharmacology, and toxicology.

RESULTS

Senecio scandens is a medicinal plant with a climbing woody stem. Phytochemical studies have shown the presence of numerous valuable compounds, such as flavonoids, alkaloids, phenolic acids, terpenes, volatile oils, carotenoids, and trace elements. Among them, PAs are the characteristic constituents, adonifoline is one of the index ingredients of Senecio scandens. Studies in modern pharmacology have demonstrated that extracts and compounds isolated from Senecio scandens show a wide spectrum of pharmacological activities, including anti-inflammatory, antimicrobial, anti-leptospirosis, hepatoprotective, anti-infusorial, antioxidant, antiviral, antitumoral, analgesic, mutagenic, and toxicological activities.

CONCLUSIONS

Phytochemical and pharmacological studies have demonstrated that the extracts of the plant possess various pharmacological activities that can be attributed to the presence of various flavonoids, phenolic acids, and alkaloids. Newer technologies for qualitative and quantitative methods of PAs need to be developed to obtain better accuracy and sensitivity. Due to the toxicity of PAs present in this medicinal plant, the regulations on PAs of Senecio scandens were varied among different countries and regions. In China, the PAs toxicity of Senecio scandens ranking criteria is not well defined in the Chinese Pharmacopoeia 2010, and there is no strict uniform requirement on the PAs in western countries. We propose that the use of Senecio scandens should be reevaluated based on a set of criteria, which includes risk-benefit analysis and severity of the toxic effects, clinical and preclinical data to ensure safe use while continuing to satisfy the need for access to the medicinal plant.

Antiplasmodial Activity of Compounds from the Surface Exudates of Senecio roseiflorus

From the surface exudates of Senecio roseiflorus fourteen known methylated flavonoids and one phenol were isolated and characterized. The structures of these compounds were determined on the basis of their spectroscopic analysis. The surface exudate and the flavonoids isolated showed moderate to good antiplasmodial activity with 5,4′-dihydroxy-7-dimethoxyflavanone having the highest activity against chloroquine-sensitive (D6) and resistant (W2) strains of Plasmodium falciparum, with IC50 values of 3.2 ± 0.8 and 4.4 ± 0.01 μg/mL respectively.

Lipoxygenase inhibitory activity of crude bark extracts and isolated compounds from Commiphora berryi

ETHNOPHARMACOLOGICAL RELEVANCE

Commiphora berryi is traditionally used for the treatment of cold and fever as well as for wound healing in the southern parts of India.

AIM OF STUDY

The present study was designed to investigate in vitro soybean lipoxygenase inhibitory activity of crude extracts and compounds isolated from Commiphora berryi.

MATERIALS AND METHODS

The bark of Commiphora berryi was extracted with different organic solvents and subjected to chromatographic separation for isolation of bioactive compounds. Structures of isolated compounds were elucidated by spectroscopic methods. The anti-inflammatory activity of bark extracts and bioactive compounds were assessed by in vitro soybean lipoxygenase (SBL) assay.

RESULTS

3β-Hydroxyglutin-5-ene (1), friedelin (2), cycloeucaneol (3) nimbiol (4), sugiol (5), surianol (6), daucosterol (7) and ursolic acid (8) were isolated from crude bark extracts of the Commiphora berryi. The structure of nimbiol (4) was also confirmed by single crystal X-ray analysis. The petroleum ether, methanol, chloroform and ethyl acetate extracts of bark of Commiphora berryi showed SBL inhibitory activity with the IC(50) values of 15.3, 54.2, 71.5 and 87.8 μg/ml respectively. Among all the isolates, friedelin (2) showed significant SBL inhibitory activity with IC(50) 35.8 μM.

CONCLUSION

The overall results provide evidence that the studied plant might be a potential source of anti-inflammatory agents.

Chemical constituents from the leaves of Aglaia perviridis

A new cinnamic acid-derived bisamide 1 and a new oplopanone-type sesquiterpenoid diglycoside 2, together with 11 known compounds, were isolated from the 95% ethanolic extract of the leaves of Aglaia perviridis. Their structures were elucidated by chemical and spectroscopic methods.

A new sesquiterpene glycoside from the aerial parts of Saussurea triangulata

Column chromatographic separation of a MeOH extract of the aerial parts of Saussurea triangulata led to the isolation of a new sesquiterpene glycoside 6, together with three quinic acid derivatives, two phenolics, two sesquiterpene glycosides and two flavonoids. The new compound 6 was identified as amarantholidol A glycoside by spectroscopic and chemical methods.