In-depth characterization of cycloartane triterpenoids and discovery of species-specific markers from three Cimicifuga species guided by a strategy that integrates in-source fragment elimination, diagnostic ion recognition, and feature-based molecular networking.

Characterization studies of the plant metabolome are crucial for revealing plant physiology, developing functional foods, and controlling quality. Mass spectrometry-based metabolite profiling allows unprecedented qualitative coverage of complex biological extract composition. However, the electrospray ionization used in metabolite profiling generates multiple artifactual signals for a single analyte, which makes it challenging to filter out redundant signals and organize the signals corresponding to abundant constituents. This study proposed a strategy integrating in-source fragments elimination, diagnostic ions recognition, and feature-based molecular networking (ISFE-DIR-FBMN) to simultaneously characterize cycloartane triterpenoids (CTs) from three medicinal Cimicifuga species. The results showed that 63.1 % of the measured ions were redundant. A total of 184 CTs were annotated, with 27.1 % being reported for the first time. It presents a promising approach to assess the composition of natural extracts, thus facilitating new ingredient registrations or natural-extracts-based drug discovery campaigns. Besides, chemometrics analysis of the three Cimicifuga species identified 32 species-specific markers, highlighting significant differences among them. The valuable information can enhance the sustainable utilization and further development of Cimicifuga resources. The codes involved in ISFE-DIR-FBMN are freely available on GitHub (https://github.com/LHJ-Group/ISFE-DIR-FBMN.git).

Bioassay-guided isolation of cycloartane-type triterpenes, their cytotoxic properties and identification of potential chemical markers from Geniotrigona thoracica propolis.

Phytochemical investigation through cytotoxicity bioassay-guided isolation of Geniotrigona thoracica propolis led to the identification of five cycloartane-type triterpenes, including mangiferonic acid 1, ambonic acid 2, mangiferolic acid 3, ambolic acid 4 and cycloartenol 5. Their structures were established based on detailed spectroscopic analysis and comparison with literature data. Compounds 1-5 were isolated for the first time in this species. From cytotoxicity MTT assay, compound 3 inhibited the growth of breast (MCF-7) and hepatocellular carcinoma (HepG2) cancer cell lines with IC50 of 5.08 and 4.82 µg/mL, respectively. Cytotoxicity of compounds 1-5 were reported for the first time against HepG2 cancer cell lines. Compounds 1-4 were suggested to serve as main and/or analytical markers for G. thoracica propolis based on HPLC analysis. To our knowledge, this is the first report on the isolation of bioactive constituents and identification of chemical markers for G. thoracica propolis.

Cycloartane-type triterpenoids from the leaves of Sandoricum koetjape and their efficacy on α-glucosidase inhibition activity.

The preliminary α-glucosidase inhibitory activity of the methanol extract of the leaves of Sandoricum koetjape Merr. exhibited promising results. The leaves was extracted with methanol to obtain the methanol extract that was continuedly partitioned with hexane and ethyl acetate. Those fractions were further purified by various chromatographic techniques. The isolation of the potent fractions furnished two new cycloartane-type triterpenoids (1 and 2) along with ten known compounds (3-12). Their chemical structures were unambiguously established by interpretation of NMR (1 D & 2 D) and high-resolution electrospray ionization mass spectrometry (HRESIMS) data. Furthermore, the configurations of two new compounds were determined by using NOESY spectrum as well as comparing their NMR data to the reference. These compounds were evaluated against α-glucosidase. All tested compounds revealed potent activity with IC50 value in the range of 2.17-49.2 µM compared to that of acarbose (IC50 100.6 µM). Compound 10 showed the lowest IC50 value. This compound was reported as a mixed-type inhibitor. Compound 3 possessed the second strong activity with an IC50 value of 14.0 µM and was further investigated on kinetic analysis which revealed as a mixed-type inhibitor with Ki and Ki' values of 59.1 and 155.2 µM, respectively.

Synthesis of Cycloartan-16ß-ol from 16ß 24R-Epoxy-Cycloartane and Their Cytotoxicity Evaluation Against Human Cancer Cell Lines.

It was found that Argentatins A and B triterpenoids make up approximately 20-30 % of the waste resin produced from the industrial processes to isolate rubber from P. argentatum. We have developed an efficient protocol for synthesizing cycloartane-16ß-ol derivatives by opening the oxepane ring of argentatin B acetate (2) with BF3-OEt2. Although three new cycloartenol derivatives showed high cytotoxicity against PC-3 and HCT-15 cancer cell lines, nevertheless, the best results were obtained for (16ß,24R) -(16,24-epoxy-cycloartan-2(1H)-ylidene) acetate (14), compound with intact oxepane ring. These results indicate that the substituents in the argentatin nucleus and a side chain account for the cytotoxic activity. However, according to the selectivity index (SI), 14 did not show selectivity activity to cancer cell lines over the HaCat noncancerous cell line. The compound 3ß,16ß-Dihydroxy-cycloartan-24-one (5), synthesized by oxepane opening, demonstrated high cytotoxic activity to cancer cell lines and showed a remarkable selectivity to cancer cell lines over the noncancerous ones. These results suggest that 5 could lead to the development of new anticancer compounds.

Characterization of four new cycloartane triterpenoids from Swietenia macrophylla and their angiotensin-I-converting enzyme inhibitory activity.

Angiotensin I-converting enzyme (ACE) inhibition is currently a common method for the treatment and control of hypertension. In this study, four new (1-4) and one known (5) cycloartane triterpenoids were isolated from the leaves of Swietenia macrophylla by chromatographic techniques and identified by their spectroscopic data and a comprehensive comparison of published data. The triterpenoids were evaluated for their ACE inhibitory potential using in vitro inhibition assays and in silico methods. The inhibition assay and enzyme kinetics results showed that the most active triterpenoid, compound 4, inhibited ACE in a mixed-type manner with an IC50 value of 57.7 ± 6.07 µM. Computer simulations revealed that compound 4 reduces the catalytic efficiency of ACE by competitive insertion into the active pocket blocking the substrate, and the binding activity occurs mainly through hydrogen bonds and hydrophobic interactions. The study showed that S. macrophylla can be a source of bioactive material and the ACE inhibitory triterpenoid could be a potential antihypertensive agent.

New ring-A modified cycloartane triterpenoids from Dysoxylum malabaricum bark: Isolation, structure elucidation and their cytotoxicity.

The Genus Dysoxylum (Meliaceae) consists of approximately 80 species that are abundant in structurally diverse triterpenoids. The present study focused on isolating new triterpenoids from the bark of Dysoxylum malabaricum, one of the predominant species of Dysoxylum present in India. The methanol-dichloromethane bark extract was subjected to LCMS profiling followed by silica gel column chromatography and HPLC analysis to target new compounds. Two new ring A-modified cycloartane-type triterpenoids (1 and 2) were isolated from the bark extract. Spectroscopic methods like NMR, HRESIMS data, and electronic circular dichroism calculations elucidated the structuresandabsolute configurations of the isolated compounds. These compounds were evaluated for their cytotoxic potential against breast cancer cells and displayed notable cytotoxicity. Compound 1 exhibited the highest cytotoxicity against the MDA-MB-231 cells and induced apoptotic cell death. Also, it was able to inhibit glucose uptake and increase nitric oxide production in breast cancer cells.

A new acylated triterpene glycoside and cytotoxic constituents from Dolichandrone serrulata (Wall. ex DC.) Seem.

In this study, a new acylated triterpene glycoside, 3α-O-stearoyl-28-[2'-stearoyl-α-l-arabinopyranosyl]-olean-12-en-28-oic acid (1), was isolated from the flowers of Dolichandrone serrulata. In addition to this compound, eleven known compounds were also isolated, including a related pentacyclic triterpenoid: ursolic acid (2), two cycloartane triterpenoids: 24-methylenecycloartanol (3) and 24-methylenecycloartane-3,28-diol (4), three cyclohexylethane derivatives: (-)-rengyolone (5), (-)-cleroindicin C (6) and (-)-cleroindicin D (7), an iridoid: 6-O-trans-feruloyl catalpol (8), two phenylethanoid glycosides: salidroside (9) and verbascoside (10), and two steroids: ß-sitosterol (11) and ß-sitosterol-3-O-ß-d-glucopyranoside (12). The chemical structures of these compounds were determined by analysing their HRMS and NMR spectroscopic data. Additionally, their cytotoxic activities against NH22, HCT116, MCF7, MDA-MB-231, and HeLa cell lines were evaluated for all the compounds. Ursolic acid exhibited moderate cytotoxic activity against all cancer cell lines tested, particularly against HN22, MDA-MB-231, MCF-7, and HCT116 cells with IC50 values of approximately 19-34 µM.

Bioactive constituents from Trichilia dregeana Sond. (Meliaceae).

The chemical investigation of the methanolic leaf extract of Trichilia dregeana Sond. led to the isolation of a hitherto unreported cycloartane-type triterpene, dregeanol (1), together with nine known compounds, (3ß,23E)-9,19-cyclolanosta-23,25-dien-3-ol (2), 9,19-cyclolanost-24-en-23-one (3), 6ß-hydroxystigmasta-4,22-dien-3-one (4), lyoniresinol (5), maslinic acid (6), asperphernamate (7), mixture of stigmasterol (8) and ß-sitosterol (9) and ß-sitosterol-3-O-ß-D-glucopyranoside (10). The structures of the isolates were elucidated by extensive spectroscopic and spectrometric analyses (1D and 2D NMR, ESI-MS) and by comparison with previously reported data. Compounds 2 and 6 showed significant antibacterial effect against Escherichia coli and Salmonella enteritidis, res-pectively, with MIC value of 31.25 µg/mL, whilst they displayed moderate antifungal effect with MIC value of 62.5 µg/mL against Candida albicans. All the isolates except compound 3 were found to possess a weak antioxidant potential in the DPPH, ABTS and FRAP assays.

Cycloartane-type triterpenoids and steroids from Trichilia connaroides and their multidrug resistance reversal activities.

Four undescribed cycloartane-type triterpenoids (1-4) and seven undescribed steroids (6-12), along with five known analogues (5 and 13-16), were isolated from the leaves of Trichilia connaroides. Their structures were identified based on the NMR data and HRESIMS, and the absolute configurations were determined through single-crystal X-ray diffraction analysis, Mosher's method, and ECD calculations. The multidrug resistance (MDR) reversal activities of all the isolates were assessed, and compounds 10 and 11 showed significant activities to reverse the MDR of MCF-7/DOX cells with IC50 values of 2.90 and 3.76 µM, respectively. These bioactive compounds may bring fresh insights into the research and development of MDR reversal agents.

New cycloartane triterpenoids from Dysoxylum malabaricum and their cytotoxic evaluation.

The cytotoxic dichloromethane-methanol bark extract of Dysoxylum malabaricum was subjected to bioassay-guided fractionation, followed by systematic dereplication to focus on the identification of new compounds. From the bark of Dysoxylum malabaricum, two new cycloartane-type triterpenoids were isolated in addition to two previously known triterpenoids. The structures and absolute configurations of the isolated compounds were elucidated unambiguously via NMR, HRESIMS data, and electronic circular dichroism calculations. The isolated compounds were tested for their cytotoxic potential against the panel of breast, lung, and hypopharynx cancer cell lines and displayed notable cytotoxicity against breast cancer cell lines. Compound 3 exhibited the most potent cytotoxic effect with an IC50 14 µM against MCF-7 cell lines and induced cell cycle arrest. Through western blot and cell cycle analysis, it was revealed that compound 3 halts the G0/G1 phase of the cell cycle by inhibiting CDC20 and CDC25 enzymes.

Cycloartane Saponins from Astragalus glycyphyllos and Their In Vitro Neuroprotective, Antioxidant, and hMAO-B-Inhibiting Effects.

Astragalus glycyphyllos (Fabaceae) is used in the traditional medicine of many countries against hepatic and cardiac disorders. The plant contains mainly flavonoids and saponins. From a defatted methanol extract from its overground parts, a new triterpenoid saponin, 3-O-[α-L-rhamnopyranosyl-(1→2)]-ß-D-xylopyranosyl]-24-O-α-L-arabinopyranosyl-3ß,6α,16ß,24(R),25-pentahydroxy-20R-cycloartane, together with the rare saponin astrachrysoside A, were isolated using various chromatography methods. The compounds were identified via extensive high resolution electrospray ionisation mass spectrometry (HRESIMS) and NMR analyses. Both saponins were examined for their possible antioxidant and neuroprotective activity in three different in vitro models. Rat brain synaptosomes, mitochondria, and microsomes were isolated via centrifugation using Percoll gradient. They were treated with the compounds in three different concentrations alone, and in combination with 6-hydroxydopamine or tert-butyl hydroperoxide as toxic agents. It was found that the compounds had statistically significant dose-dependent in vitro protective activity on the sub-cellular fractions. The compounds exhibited a weak inhibitory effect on the enzyme activity of human recombinant monoamine oxidase type B (hMAO-B), compared to selegiline.

NMR-tracking for 15,16-seco-cycloartane triterpenes from Cimicifuga acerina.

Twelve undescribed 15,16-seco-cycloartane triterpenoids, 15,16-seco-cimiterpenes C-N, as well as five previously reported analogs were isolated by NMR-tracking methods from the rhizomes of Cimicifuga acerina (Sieb. et Zucc.) Tanaka. Among them, 15,16-seco-cimiterpenes C-N were the first 15,16-seco-cycloartane triterpenoids featuring acetal or hemiacetal structures at C-15. The chemical structures of 15,16-seco-cimiterpenes C-N were determined based on comprehensive spectroscopic analysis, chemical method, and comparison with the previous literature data. After that, all these compounds were evaluated for their lipid-lowering effects on 3T3-L1 adipocytes.15,16-seco-cimiterpene D was found to exhibit a comparable reducing lipid effect at the concentration of 50 µM, with an inhibition rate at 35.96%.

Cycloartane triterpenoid from Euphorbia macrostegia modulates ER stress signaling pathways to induce apoptosis in MDA-MB231 and MCF-7 breast cancer cell lines.

Unfolded protein response (UPR) is involved in breast cancer (BC) progression and drug resistance. Many natural products (NPs) could modulate UPR and used for therapeutic purposes. Herein, we aimed to investigate the molecular mechanism of Cycloart-23E-ene-3ß, 25-diol (Cycloart-E25), cytotoxicity, as a NP extracted from Euphorbia macrostegia and focused on endoplasmic-reticulum stress (ERS) and UPR signaling pathways. Reactive oxygen species (ROS) were probed by DCFDA fluorescence dye. Apoptosis was assayed by annexin V/propidium iodide (PI), immunoblotting of anti- and proapoptotic, Bcl-2 and Bax proteins, and mitochondrial transmembrane potential (ΔΨm) changes. Thioflavin T (ThT) staining and immunoblotting of UPR signaling components (CHOP, PERK, ATF6, BiP, and XBP1) were recruited for the assessment of ERS. Our results indicated that Cycloart-E25 noticeably increases ROS levels in both MB-231 MDA-MB-231 and MCF-7 cell lines, p>0.05. Flow cytometry assessments revealed an increase in the cell population undergoing apoptosis. Also, the Bax/Bcl-2 ratio increased in a dose-dependent manner following Cycloart-E25 treatment, significantly, p>0.05. Mitochondrial involvement could be deduced by significant decreases in ΔΨm, p>0.05. Cycloart-E25 potently induces protein aggregation and upregulated CHOP, PERK, ATF6, BiP, and XBP1 factors in both MDA-MB-231 MB-231 and MCF-7 cell lines, indicating the involvement of ERS in Cycloart-E25-mediated apoptosis. In conclusion, Cycloart-E25 increased the accumulation of misfolded proteins and upregulated UPR components. Therefore, induction of ERS may be involved in the trigger of apoptosis in BC cell lines. Cycloart-E25 induced apoptosis in breast cancer cell lines through ERS. More assessments are needed to confirm its in vivo anti-tumoral effects.

Natural Cycloartane Triterpenoids from Corypha utan Lamk. with Anticancer Activity towards P388 Cell Lines and their Predicted Interaction with FLT3.

BACKGROUND: Cancer is the second leading cause of death in the world. Leukemia is a type of cancer that accounts for 31.5% of all cancers in children under the age of 15 in industrialized countries and 15.7% in developing countries. The inhibition of FMS-like tyrosine kinase 3 (FLT3) is a suitable approach for acute myeloid leukemia (AML) therapy as it is overexpressed in AML. AIM AND OBJECTIVE: This study intends to explore the natural constituents from the bark of Corypha utan Lamk., and assess their cytotoxicity on murine leukemia cell lines (P388) in addition to predicting their interaction with FLT3 as a studied target by computational methods. METHODS: Compounds 1 and 2 were isolated from Corypha utan Lamk using the stepwise radial chromatography method. These compounds were assessed for their cytotoxicity against Artemia salina using the BSLT and P388 cells and the MTT assay. The docking simulation was employed to predict the possible interaction between triterpenoid and FLT3. RESULTS: Isolation from the bark of C. utan Lamk. generated two triterpenoids, cycloartanol (1) and cycloartanone (2). Based on the in vitro and in silico studies, both compounds were found to have anticancer activity. The evaluation of cytotoxicity from this study reveals that cycloartanol (1) and cycloartanone (2) could inhibit P388 cell growth (IC50 value at 102.6 and 110.0 µg/mL, respectively). The binding energy of cycloartanone was -9.94 Kcal/mol with a Ki value of 0.051 µM, while the binding energy and Ki value of cycloartanol (1) were found to be 8.76 Kcal/mol and 0.38 µM, respectively. These compounds also demonstrate a stable interaction by forming hydrogen bonds with FLT3. CONCLUSION: Cycloartanol (1) and cycloartanone (2) exhibit potency as anticancer agents by inhibiting P388 cells in vitro and the FLT3 gene in silico.

Two new cycloartane type triterpenes from Dysoxyllum binectariferum.

Dysoxyllum binectariferum is an important medicinal plant known for various biological activities like anti-inflammatory, CNS depressants, contraceptive, analgesic, immunomodulatory, antimalarial, antifeedant, leishmanicidal and antiviral. It is a rich source of rohitukine, a basic skeleton of flavopiridol. Phytochemical investigation of chloroform extracts of Dysoxyllum binectariferum leaves, lead to the isolation of beddomeilactone (1) and two new cycloartane type triterpenoids beddomeilactol (2) and binectarilactone-A (3) with modified A ring. Compounds were assessed for their in-vitro α-glucosidase inhibitory activity. Compound 1 was found to be most potent, showing IC50 of 17.99 ± 0.26 µg/ml which is comparable to the positive control acarbose.

Chemical constituents from Abies chensiensis and their antifungal activity.

One new (1) and six known cycloartane triterpenoids (2-7), along with seven reported abietane diterpenoids (8-14), were isolated from the bark of the branches of Abies chensiensis, of which compounds 2-14 were also received for the first time from the genus of Abies. Structural elucidation of all the compounds was carried out by extensive spectroscopic analyses. Additionally, the antifungal activity of isolated compounds 2-13 was evaluated by inhibiting the growth of fungal mycelium. Among them, compounds 8 and 10 demonstrated obvious inhibitory activity against plant pathogens Fusarium avenaceum and Bipolaris sorokiniana.

New cycloartane coronalyl acetate and other terpenoids with anti-inflammatory activity from the leaves of Vietnamese Gardenia philastrei.

Phytochemical study on the methanolic extract of the leaves of Vietnamese plant Gardenia philastrei Pierre ex Pit. has led to the isolation of a new cycloartane coronalyl acetate (1) together with six known ones, coronlolide methyl ester (2), sootepin D (3), coronalolide (4), coronalolic acid (5), sootepin G (6) and 23-deoxojessic acid (7). Their structures were elucidated by a combination of 2 D NMR and HR-ESI-MS spectroscopies. These compounds (1-7) were tested for their anti-inflammatory activity. The result showed that six compounds (1-6) inhibit LPS-induced nitric oxide production in RAW264.7 macrophages with their IC50 values ranging from 3.76 - 75.47 µg/mL. This is the first report on the chemical constituents and anti-inflammatory activity of the G. philastrei.

Lehmanniaside, a new cycloartane triterpene glycoside from Astragalus lehmannianus.

Chemical investigation of the aerial parts of Astragalus lehmannianus Bunge (Leguminosae) led to the isolation and identification of a new cycloartane triterpene glycoside - lehmanniaside (2'-O-acetyl-3-ß-O-D-xylopyranosyl-3ß,6α,16ß,24α-tetrahydroxy-20,25-epoxycycloartane). Its structure was elucidated by means of spectroscopic analysis (HR-MS, 1D and 2D NMR). Bioassays showed that lehmanniaside exhibits weak anthelmintic, antifungal, and cytotoxic activities.

Cycloartanes from leaves of Combretum quadrangulare growing in Vietnam.

Two new cycloartanes, combretic acid C (1) and combretanone I (3), were isolated from the leaves of Combretum quadrangulare Kurz, together with the previously-reported combretic acids A-B (2 and 5) and combretanone A (4). An extensive set of spectroscopic methods were used to elucidate the structures of these compounds. Cytotoxicity against the K562 cancer cell line was evaluated. Compound 1 showed strong activity, with an IC50 value of 9.7 µM. The other compounds showed moderate activity. Alpha-glucosidase inhibition was also evaluated. The isolated compounds showed moderate inhibition, with IC50 values in the range 102.2-194.7 µM.

Two new cycloartane triterpenoid glycosides from the rhizomes of Actaea vaginata.

Two new cycloartane triterpenoid glycosides, soulieoside V (1) and 15-deacetylbeesioside O (2), together with one known compound, beesioside J (3), were isolated from the ethanolic extract of the rhizomes of Actaea vaginata. Their structures were elucidated by spectroscopic methods and by comparison with data reported in the literature. All the compounds were tested for their cytotoxic activities against human cancer cell lines.