Showing papers on "Triterpene published in 2021"

Anti-Inflammatory, Antidiabetic Properties and In Silico Modeling of Cucurbitane-Type Triterpene Glycosides from Fruits of an Indian Cultivar of Momordica charantia L.

Abstract: Diabetes mellitus is a chronic disease and one of the fastest-growing health challenges of the last decades. Studies have shown that chronic low-grade inflammation and activation of the innate immune system are intimately involved in type 2 diabetes pathogenesis. Momordica charantia L. fruits are used in traditional medicine to manage diabetes. Herein, we report the purification of a new 23-O-β-d-allopyranosyl-5β,19-epoxycucurbitane-6,24-diene triterpene (charantoside XV, 6) along with 25ξ-isopropenylchole-5(6)-ene-3-O-β-d-glucopyranoside (1), karaviloside VI (2), karaviloside VIII (3), momordicoside L (4), momordicoside A (5) and kuguaglycoside C (7) from an Indian cultivar of Momordica charantia. At 50 µM compounds, 2-6 differentially affected the expression of pro-inflammatory markers IL-6, TNF-α, and iNOS, and mitochondrial marker COX-2. Compounds tested for the inhibition of α-amylase and α-glucosidase enzymes at 0.87 mM and 1.33 mM, respectively. Compounds showed similar α-amylase inhibitory activity than acarbose (0.13 mM) of control (68.0-76.6%). Karaviloside VIII (56.5%) was the most active compound in the α-glucosidase assay, followed by karaviloside VI (40.3%), while momordicoside L (23.7%), A (33.5%), and charantoside XV (23.9%) were the least active compounds. To better understand the mode of binding of cucurbitane-triterpenes to these enzymes, in silico docking of the isolated compounds was evaluated with α-amylase and α-glucosidase.

Progress in the Studies of Triterpene Glycosides From Sea Cucumbers (Holothuroidea, Echinodermata) Between 2017 and 2021:

Abstract: Structural diversity of triterpene glycosides produced by sea cucumbers or holothurians (Holothuroidea, Echinodermata) is extremely high, although all of them are either lanostane derivatives or, r...

Triterpene Acids from Mesona procumbens Exert Anti-inflammatory Effects on LPS-Stimulated Murine Macrophages by Regulating the MAPK Signaling Pathway.

Abstract: Five new triterpene acids, mesonaic acids A-C (1-3), 2α,3α,19α-trihydroxy-24-nor-4(23),12-oleanadien-28-oic acid (4), and 3α,19α,22α-trihydroxy-2-oxo-12-ursen-28-oic acid (5), and 10 known triterpene acid compounds (6-15) were isolated from a methanolic extract of Mesona procumbens. Triterpenes 1-3 possess unusual hexacyclic skeletons with a 13α,27-cyclopropane ring. Regarding their anti-inflammatory activity, compounds 1-3, 6, and 7 inhibited NO production with EC50 values lower than 15 μM, which were better than that of the positive control quercetin. Compounds 1-3, 6, and 7 markedly decreased levels of the inducible iNOS and COX-2 proteins in macrophages by inhibiting the activation of NF-κB through interference with the MAPK signaling pathway. Based on these data, compounds 1-3, 6, and 7 have great potential as NO inhibitors.

New Triterpene Glycosides from the Far Eastern Starfish Solaster pacificus and Their Biological Activity.

Abstract: Three new triterpene glycosides, pacificusosides A-C (1-3), and three previously known triterpene glycosides, cucumariosides C1 (4), C2 (5), and A10 (6), were isolated from the alcoholic extract of the Far Eastern starfish Solaster pacificus. The structures of 1-3 were elucidated by extensive NMR and ESIMS techniques and chemical transformations. Compound 1 has a novel, unique structure, containing an aldehyde group of side chains in its triterpene aglycon. This structural fragment has not previously been found in the sea cucumber triterpene glycosides or starfish steroidal glycosides. Probably, pacificusoside A (1) is a product of the metabolism of the glycoside obtained through dietary means from a sea cucumber in the starfish. Another two new triterpene glycosides (2, 3) have closely related characteristics to sea cucumber glycosides. The cytotoxicity of compounds 1-6 was tested against human embryonic kidney HEK 293 cells, colorectal carcinoma HT-29 cells, melanoma RPMI-7951 cells, and breast cancer MDA-MB-231 cells using MTS assay. Compounds 4-6 revealed the highest cytotoxic activity against the tested cell lines, while the other investigated compounds had moderate or slight cytotoxicity. The cytotoxic effects of 2-6 were reduced by cholesterol like the similar effects of the previously investigated individual triterpene glycosides. Compounds 3, 4, and 5 almost completely suppressed the colony formation of the HT-29, RPMI-7951, and MDA-MB-231 cells at a nontoxic concentration of 0.5 µM.

Amyloid β aggregation inhibitory activity of triterpene saponins from the cactus Stenocereus pruinosus

Abstract: Six new triterpene saponins (1–5,7) and 3 known saponins (6,8,9) were isolated from MeOH extracts of the cactus Stenocereus pruinosus. The structures of the isolated saponins were elucidated using MS, IR, and comprehensive NMR measurements. To develop drugs for treating Alzheimer’s disease (AD) on the basis of the amyloid cascade hypothesis, the isolated saponins were evaluated for inhibition of BACE1 activity and amyloid beta (Aβ) aggregation using thioflavin-T assay, and triterpenes as an aglycone moiety and an alkaline hydrolysate of the saponins were also evaluated. One saponin, stenoside A (7), exhibited inhibitory activity related to Aβ aggregation and its degree of Aβ aggregation was 40.6% at 100 μM.

Biological Activities and Chemistry of Triterpene Saponins from Medicago Species: An Update Review

Abstract: Plants are known to be a great source of phytochemicals for centuries Medicago, belonging to the Family Fabaceae, is a large and well spread genus comprising about 83 cosmopolitan species, of which one-third are annuals and span diverse ecological niches Medicago species are rich in saponins mainly classified into three classes, namely, steroid alkaloid glycosides, triterpene glycosides, and steroid glycosides These saponins are important compounds having diverse pharmacological and biological activities As a whole, 95 of saponins are reported to date occurring in Medicago species using various latest extraction/isolation techniques Considering the multiple biological and pharmacological potential of Medicago species due to saponins along with structural diversity, we compiled this review article to sum up the recent reports for the pharmacological potential of the Medicago's derived saponins in modern as well as traditional medication systems The current manuscript produces data of chemical structures and molecular masses of all Medicago species saponins simultaneously The toxicity of certain pure saponins (aglycones) has been reported in vitro; hederagenin appeared highly toxic in comparison to medicagenic acid and bayogenin against X index, while soyasaponin I, containing soyasapogenol B as a glycone, appeared as the least toxic saponin The diversity in the structural forms shows a close relationship for its biological and pharmacological actions Moreover, saponins showed antioxidant properties and the mechanism behind antimicrobial potential also elaborated in this review article is mainly because of the side sugar groups on these compounds The collected data presented herein include chemical structures and molecular masses of all saponins so far Their biological activity and therapeutic potential are also discussed This information can be the starting point for future research on this important genus

Quali–Quantitative Characterization of Volatile and Non-Volatile Compounds in Protium heptaphyllum (Aubl.) Marchand Resin by GC–MS Validated Method, GC–FID and HPLC–HRMS2

Abstract: Protium heptaphyllum (Aubl.) Marchand (PH) trees are endemic to the tropical region of South America, mostly Brazil. Antibacterial, antinociceptive, anti-inflammatory, anxiolytic, antidepressant and anti-hyperlipidemic/anti-hypercholesterolemic effects were reported for its resinous exudate Protiumheptaphyllum resin (PHR). This work aims to provide a qualitative and quantitative consistent chemical profiling of the major constituents of this resin and two extracts enriched in acid (acidic triterpene concentrated extract, ATCE) and neutral triterpenes (α and β-amyrin concentrated extract, AMCE). GC–MS/GC–FID was used for volatile terpene fraction, a validated GC–MS method was developed for quantification of neutral α and β-amyrin and HPLC–APCI HRMS2 was used for acidic triterpenes analysis. The chemical investigation reported 29 molecules, including 14 volatile terpenes, 6 neutral triterpenes and 11 acid triterpenes. The most abundant compounds were α-amyrin (251.28 g kg−1, 123.98 g kg−1 and 556.82 g kg−1 in PHR, ATCE and AMCE, respectively), β-amyrin (172.66 g kg−1, 95.39 g kg−1 and 385.58 g kg−1 in PHR, ATCE and AMCE, respectively), 3-oxo-tirucalla-7,24-dien-21-oic acid (80.64 g kg−1, 157.10 g kg−1 and 15.31 g kg−1 in PHR, ATCE and AMCE, respectively) and 3α-hydroxy-tirucalla-8,24-dien-21-oic acid (77.71 g kg−1, 130.40 g kg−1 and 11.64 g kg−1 in PHR, ATCE and AMCE, respectively). Results showed specific enrichment of acidic and neutral triterpenoids in the two respective extracts.

Sulfated Triterpene Glycosides from the Saudi Red Sea Cucumber Holothuria atra with Antioxidant and Cytotoxic Activities

Abstract: The bioactive constituents of sea cucumber Holothuria atra were investigated, and four sulfated holostan-type triterpene glycosides (1–4) along with other seven know metabolites were obtained. On the basis of the extensive NMR and ESI-MS data, the structures of triterpenoid saponins were assigned as a new compound echinoside B 12-O-methyl ether (1), and known echinoside B (2), 24-dehydroechinoside B (3), and holothurin B (4). The extract and isolated saponins displayed weak antioxidant DPPH radical scavenging activities, where echinoside B (2) showed the highest value at 26.41%. However, 24-dehydroechinoside B (3) showed mild antioxidant-reducing power activity (0.19 nm), compared to the synthetic antioxidant (BHT). Both compounds 2 and 3 exhibited moderate cytotoxic activity by reducing the viability of Ehrlich ascites carcinoma cells to 41.0% and 42.2%, respectively, compared to the drug control vincristine (95.2%).

Methyl Jasmonate and Methyl-β-Cyclodextrin Individually Boost Triterpenoid Biosynthesis in Chlamydomonas Reinhardtii UVM4.

Abstract: The commercialisation of valuable plant triterpenoids faces major challenges, including low abundance in natural hosts and costly downstream purification procedures. Endeavours to produce these compounds at industrial scale using microbial systems are gaining attention. Here, we report on a strategy to enrich the biomass of the biotechnologically-relevant Chlamydomonas reinhardtii strain UVM4 with valuable triterpenes, such as squalene and (S)-2,3-epoxysqualene. C. reinhardtii UVM4 was subjected to the elicitor compounds methyl jasmonate (MeJA) and methyl-β-cyclodextrine (MβCD) to increase triterpene yields. MeJA treatment triggered oxidative stress, arrested growth, and altered the photosynthetic activity of the cells, while increasing squalene, (S)-2,3-epoxysqualene, and cycloartenol contents. Applying MβCD to cultures of C. reinhardtii lead to the sequestration of the two main sterols (ergosterol and 7-dehydroporiferasterol) into the growth medium and the intracellular accumulation of the intermediate cycloartenol, without compromising cell growth. When MβCD was applied in combination with MeJA, it counteracted the negative effects of MeJA on cell growth and physiology, but no synergistic effect on triterpene yield was observed. Together, our findings provide strategies for the triterpene enrichment of microalgal biomass and medium.

Isomadecassoside, a New Ursane-Type Triterpene Glycoside from Centella asiatica Leaves, Reduces Nitrite Levels in LPS-Stimulated Macrophages.

Abstract: A madecassoside-rich fraction obtained from the industrial purification of Centella asiatica leaves afforded a new triterpene glycoside, named isomadecassoside (4), characterized by an ursane-type skeleton and migration of the double bond at Δ20(21) in ring E. The structure of isomadecassoside was established by means of HR-ESIMS and detailed analysis of 1D and 2D NMR spectra, which allowed a complete NMR assignment. Studies on isolated J774A.1 macrophages stimulated by LPS revealed that isomadecassoside (4) inhibited nitrite production at non-cytotoxic concentrations, thus indicating an anti-inflammatory effect similar to that of madecassoside.

Phytochemical Investigation and Differential Effects of Cestrum elegans Isolated Compounds as Antimicrobial and Virucidal against Hepatitis A Virus

Abstract: A new steroidal saponin, named as (25R)-6α-[(β-D-glucopyranosyl) oxy]-5α-spirostan-3β-yl β-D-glucopyranosyl (1''→3')-O-β-D-glucopyranosid (2) was isolated from the flowers of Cestrum elegans. In addition, a known steroidal saponin (1), a flavonoid compound (3) along with a triterpene saponin (4) were isolated for the first time in genus Cestrum and identified based on their chromatographic properties, chemical and spectral data (HR-ESI-MS, 1H, 13C NMR, 1H-1H COSY, HSQC, and HMBC). The four compounds are characterized by different effects against Gram positive, Gram negative bacteria, antifungal and antiviral activities. The maximum non-toxic concentration (MNTC) on vero cell line was 1.56 µg/mL for all compounds. While compound 1 and 3 showed the highest biological activities against hepatitis A virus possess 34.3% and 25% antiviral activity respectively..

Sterols and Triterpenes from Dobera glabra Growing in Saudi Arabia and Their Cytotoxic Activity.

Abstract: A new lupane caffeoyl ester, lup-20(29)-ene 3β-caffeate-30-al (7), and a new oleanane-type triterpene, 3β-hydroxyolean-13(18)-en-12-one (17), were isolated from the aerial parts of Dobera glabra (Forssk), along with ten known triterpenes, including seven lupane-type lupeol (1), 30-nor-lup-3β-ol-20-one (2), ∆1-lupenone (3), lup-20(29)-en-3β,30-diol (4), lupeol caffeate (5), 30-hydroxy lup-20(29)-ene 3β-caffeate (6), and betunaldehyde (8); three oleanane-type compounds were also identified, comprising δ-amyrone (15), δ-amyrin (16), and 11-oxo-β-amyrin (18); together with six sterols, comprising β-sitosterol (9), stigmasterol (10), 7α-hydroxy-β-sitosterol (11), 7α-hydroxy-stigmasterol (12), 7-keto-β-sitosterol (13), and 7-keto-stigmasterol (14). Their structures were elucidated using a variety of spectroscopic techniques, including 1D (1H, 13C, and DEPT-135 13C) and 2D (1H–1H COSY, 1H–13C HSQC, and 1H–13C HMBC) nuclear magnetic resonance (NMR) and accurate mass spectroscopy. Subsequently, the different plant extracts and some of the isolated compounds (1–9, 11 and 13) were investigated for their possible cytotoxic activity in comparison to cisplatin against a wide array of aggressive cancer cell lines, such as colorectal cancer (HCT-116), hepatocellular carcinoma (HepG-2), and prostate cancer (PC-3) cell lines. Compound 11 displayed broad cytotoxicity against all of the tested cell lines (IC50 ≅ 8 µg/mL in all cases), and a high safety margin against normal Vero cells (IC50 = 70 µg/mL), suggesting that 11 may be a highly selective and effective anticancer agent candidate. Notably, the evidence indicated that the mode of action of compound 11 could possibly consist of the inhibition of phosphodiesterase I (80.2% enzyme inhibition observed at 2 µM compound concentration).

A BAHD acetyltransferase contributes to wound-induced biosynthesis of oleo-gum resin triterpenes in Boswellia

Abstract: Triterpenes (30-carbon isoprene compounds) represent a large and highly diverse class of natural products that play various physiological functions in plants. The triterpene biosynthetic enzymes, particularly those catalyzing the late-stage regio-selective modifications are not well characterized. The bark of select Boswellia trees, e.g., B. serrata exudes specialized oleo-gum resin in response to wounding, which is enriched with boswellic acids (BAs), a unique class of C3α-epimeric pentacyclic triterpenes with medicinal properties. The bark possesses a network of resin secretory structures comprised of vertical and horizontal resin canals, and amount of BAs in bark increases considerably in response to wounding. To investigate BA biosynthetic enzymes, we conducted tissue-specific transcriptome profiling and identified a wound-responsive BAHD acetyltransferase (BsAT1) of B. serrata catalyzing the late-stage C3α-O-acetylation reactions in the BA biosynthetic pathway. BsAT1 catalyzed C3α-O-acetylation of αBA, βBA, and 11-keto-βBA in vitro and in planta assays to produce all the major C3α-O-acetyl-BAs (3-acetyl-αBA, 3-acetyl-βBA, and 3-acetyl-11-keto-βBA) found in B. serrata bark and oleo-gum resin. BsAT1 showed strict specificity for BA scaffold, whereas it did not acetylate the more common C3β-epimeric pentacyclic triterpenes. The analysis of steady-state kinetics using various BAs revealed distinct substrate affinity and catalytic efficiency. BsAT1 transcript expression coincides with increased levels of C3α-O-acetyl-BAs in bark in response to wounding, suggesting a role of BsAT1 in wound-induced biosynthesis of C3α-O-acetyl-BAs. Overall, the results provide new insights into the biosynthesis of principal chemical constituents of Boswellia oleo-gum resin.