Cucurbitane-type Triterpene Glycosides Research Articles

Introduction, adaptation and characterization of monk fruit (Siraitia grosvenorii): a non-caloric new natural sweetener

Siraitia grosvenorii, an herbaceous perennial plant, native to the southern parts of China, is commonly used as a low-calorie natural sweetener. It contains cucurbitane-type triterpene glycosides known as mogrosides. The extract from monk fruit is about 300 times sweeter than sucrose. In spite of its immense importance and International demand, Siraitia grosvenorii (Swingle) is not commercially cultivated outside China since scientific information for cultivation of this species is lacking. Planting material of monk fruit plant was not available in India. Thus, the seeds of monk fruit were introduced in India from China after following International norms. Then the experiments were conducted on different aspects such as seed germination, morphological and anatomical characterization, phenology, flowering and pollination behaviors, and dynamic of mogroside-V accumulation in fruit. The hydropriming at 40 °C for 24 h was found effective to reduce the germination time and to increase the germination rate (77.33%). The multicellular uniseriate trichomes were observed in both the leaf surfaces, however, higher trichomes density was observed in the ventral surface of males compared to females. The microscopic view revealed that the ovary was trilocular (ovary consists three chambers) having two ovules in each chamber or locule. Most of the fruits were globose or oblong type with 5–7 cm in length and 4–7 cm diameter. Mogroside-V content in fruit at 80 days after pollination was 0.69% on dry weight basis. The rate of increase of mogroside-V accumulation from 50 to 70 days was very slow, whereas a sharp increase was observed from 70 to 80 days. The higher receptivity of stigma was observed with fully open flowers. The floral diagram and formula have also been developed for both male and female flowers. Our results highlighted that monk fruit can be grown in Indian conditions.

Cucurbitane-Type Triterpene Glycosides from Momordica charantia and Their \u03b1-Glucosidase Inhibitory Activities

Ten cucurbitane-type triterpene glycosides, including five new compounds named charantosides H (1), J (2), K (3), momorcharacoside A (4), goyaglycoside-l (5), and five known compounds (6–10), were isolated from the EtOAc extract of Momordica charantia fruits. The chemical structures of these compounds were identified by 1D and 2D NMR and HRESIMS spectroscopic analyses. Configurations of new compounds were determined by ROESY correlations and comparison of their 13C NMR data with literature reported values. All compounds were evaluated for their inhibition against α-glucosidase, in which compounds 2, 5, 7, 8, 9 showed moderate inhibitory activities with IC50 values ranging from 28.40 to 63.26 μM comparing with the positive control (acarbose, IC50 87.65 ± 6.51 μM).Graphic

Collagen synthesis-promoting and collagenase inhibitory activities of constituents isolated from the rhizomes of Picrorhiza kurroa Royle ex Benth

Three new acylated phenylethanoid glycosides, kurroaosides A (14), B (15), and C (16), and a new acylated cucurbitane-type triterpene glycoside, kurroaoside D (17), were isolated from a methanol extract of the rhizomes of Picrorhiza kurroa Royle ex Benth. (Plantaginaceae) along with 29 known isolates including 10 acylated phenylethanoid glycosides (18–27), three cucurbitane-type triterpene glycosides (32–34), and a nortriterpene glycoside (35). The structures of these new compounds (14–17), including their stereochemistry, were determined based on chemical and physicochemical evidence derived from NMR and MS analysis. Among the isolates, acylated iridoid glycosides, picrosides I (8), II (9), III (10), and IV (11) and 6-feruloylcatalpol (12), phenylethanoid glycosides (14–16), triterpene glycosides, cucurbitacin B 2-O-β-D-glucopyranoside (32) and 25-acetoxy-2-β-D-glucopyranosyloxy-3,16,20-trihydroxy-9-methyl-19-norlanosta-5-en-22-one (35), and an acetophenone glycoside, picein (36), significantly promoted collagen synthesis at 10–30 μM, with no cytotoxicity being observed at the effective concentrations. Furthermore, acylated phenylethanoid glycosides, calceolarioside A (19, IC50 = 69.2 μM), plantamajoside (20, 51.8 μM), isoplantamajoside (21, 76.8 μM), and scroside E (23, 65.5 μM), exhibited collagenase inhibitory activity equivalent to that of positive agents caffeic acid (75.6 μM) and epigallocatechin 3-O-gallate (75.4 μM).

Cucurbitane triterpenoids from the fruit of Momordica charantia L. and their anti-hepatic fibrosis and anti-hepatoma activities

Momordica charantia L. (Cucurbitaceae) is a popular vegetable and traditional folk medicine, that has been used for hundreds of years. In this study, three undescribed cucurbitane-type triterpene glycosides furpyronecucurbitane A, goyaglycoside I and charantagenin F along with nine known compounds were isolated from the immature fruit of Momordica charantia L. Their structures were identified on the basis of extensive 1D, 2D NMR and HRESIMS spectroscopy analysis. All isolated compounds were examined for their anti-hepatic fibrosis activity against murine hepatic stellate cells (t-HSC/Cl-6) and anti-hepatoma activity against two kinds of liver cancer cell lines (HepG2 and Hep3B). Among them, karaviloside III exhibited excellent inhibitory activity against activated t-HSC/Cl-6 cells and cytotoxic activity against Hep3B and HepG2 cell lines with IC50 values of 3.74 ± 0.13, 16.68 ± 2.07 and 4.12 ± 0.36 μM, respectively, which may potential to be developed as a chemotherapy agent for treatment hepatic fibrosis or carcinoma and protection against both diseases.

Cucurbitacins from the Leaves of Citrullus colocynthis (L.) Schrad.

Two new tetracyclic cucurbitane-type triterpene glycosides were isolated from an ethyl acetate extract of Citrullus colocynthis leaves together with four known cucurbitacins. Their structures were established on the basis of their spectroscopic data (mainly NMR and mass spectrometry). Evaluation of the in vitro cytotoxic activity of the isolated compounds against two human colon cancer cell lines (HT29 and Caco-2) and one normal rat intestine epithelial cell line (IEC6), revealed that one of the isolated compounds presented interesting specific cytotoxic activity towards colorectal cell lines.

The cytotoxicology of momordicins I and II on Spodoptera litura cultured cell line SL-1

Momordicin I and II are secondary metabolites from bitter melon (Momordica charantia L.) that are toxic to the Spodoptera litura ovary cell line (SL-1 cell). Both momordicin I and II significantly inhibited SL-1 cells proliferation. IC50 values after 24 h were 8.35 and 82.31 µg/mL, 6.11 and 77.49 µg/mL for 36 h, 4.93 and 49.42 µg/mL for 48 h for cells treated by momordicin I and II, respectively. IC50 values of the azadirachtin A control were 149.63, 54.54 and 23.66 µg/mL at 24, 36 and 48 h respectively, indicating that the cytotoxicity of momordicin I was significantly higher than that of momordicin II and azadirachtin A. Using inverted phase contrast microscopy we found that after 24 h exposure to momordicin I and II, cell shapes changed to circular, swelling increased, adherence ability declined and the cellular membrane bubbled. After 48 h exposure to momordicin I, most cells were suspended and dead; vacuole deformation and cytoplasm leakage indicated that momordicin I was more toxic to the cytoskeleton than momordicin II.Cells treated with momordicin I and II inhibited glucose absorption by 23.04 and 13.38% after 48 h and 47.60 and 20.92% after 60 h. Flow cytometry analysis suggested that SL-1 cells treated with momordicin I and II dramatically accumulated during the G2/M phase of the cell cycle, and total cell protein content increased by 56.93 and 35.81% respectively after 48 h treatment. Following treatment with momordicin I and II the karyotheca dissolved, the chromatin condensed abnormally and the nucleoli were damaged, migrated, or disappeared. The PI fluorescent value by FCM showed that the relative fluorescent intensity of SL-1 cells induced by momordicin I and II increased to 521.45 and 370.17, higher than 135.04 induced by control group treatment for 48 h. This indicated significant damage to the cytomembrane. Overall, the results demonstrate that suppression of cytoskeletal function, interference of mitotic figures and destruction of nuclear structure are effects of momordicin I and II exposure. These effects play major roles in momordicin I and II inhibition of SL-1 cells growth. The mode of action by which momordicins inhibit insect cell growth and development may be useful in the development of novel pest control formulations containing cucurbitane-type triterpene glycosides.

Cucurbitane-typeTriterpene Glycosides from the Fruits ofMomordica charantia

Four new cucurbitane-type triterpene glycosides, charantosides D-G (1-4) were isolated from a methanol extract of Momordica charantia fruits. The structures of these compounds were determined by chemical and spectroscopic methods to be (19R)-5 beta,19-epoxy-25-methoxycucurbita-6,23-diene-3 beta,19-diol 3-O-beta-D-glucopyranoside, (19R)-5 beta, 19-epoxy-25-methoxycucurbita-6,23-diene-3 beta,19-diol 3-O-beta-D-allopyranoside, 7 beta-methoxycucurbita-5,23E,25-triene-3 beta-ol 3-O-beta-D-allopyranoside, and 3 beta,7 beta-dihydroxycucurbita-5,23E,25-triene- 19-al 3-O-beta-D-allopyranoside.

Antiproliferative and Hypoglycemic Cucurbitane-Type Glycosides from the Fruits of Momordica charantia

This paper reports that bioassay-guided fractionations of EtOH extract of Momordica charantia fruits led to the isolation of 15 cucurbitane-type triterpene glycosides including 4 new compounds, kuguaosides A-D (1-4), along with 11 known ones, charantoside A (5), momordicosides I (6), F1 (7), F2 (8), K (9), L (10), and U (11), goyaglycosides-b (12) and -d (13), 7β,25-dihydroxycucurbita-5,23(E)-dien-19-al 3-O-β-d-allopyranoside (14), and 25-hydroxy-5β,19-epoxycucurbita-6,23-dien-19-on-3β-ol 3-O-β-d-glucopyranoside (15). Their structures were elucidated on the basis of spectroscopic analyses and chemical methods. This study also established the HPLC-ELSD fingerprinting profile of an antiproliferative fraction of which 11 main peaks were identified. Biological evaluation showed that several isolated cucurbitane-type triterpene glycosides had antiproliferative activities against MCF-7, WiDr, HEp-2, and Doay human tumor cell lines. In addition, compound 14 showed potent hypoglycemic activities by glucose uptake assay.

Structures of New Triterpenoids and Cytotoxicity Activities of the Isolated Major Compounds from the Fruit of Momordica charantia L.

Two new cucurbitane-type triterpene glycosides, charantagenins D (1) and E (2), and one new sterol, 7-oxo-stigmasta-5,25-diene-3-O-β-d-glucopyranoside (3), were isolated from the fruit of Momordica charantia L. together with another eight known compounds. Their structures were determined on the basis of spectral analysis. Cytotoxicity activities of the isolated major compounds were evaluated against lung cancer cell line A549, glioblastoma cell line U87, and hepatoma carcinoma cell line Hep3B by using a 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) in vitro assay. Results showed compounds 1 and 7 (goyaglycoside d) with an -OMe substituent group in the side chain exhibited significant cytotoxic activities against cancer cells. Impressively, the IC(50) values of the new compound 1 to A549, U87, and Hep3B were 1.07, 1.08, and 14.01 μmol/L, respectively, which were much lower than those of other tested compounds.

Inhibition of Nuclear Transcription Factor-κB and Activation of Peroxisome Proliferator-Activated Receptors in HepG2 Cells by Cucurbitane-Type Triterpene Glycosides fromMomordica charantia

Momordica charantia is used to treat various diseases, including inflammatory conditions. Previous reports indicated that the extract of this plant inhibits activation of nuclear transcription factor-κB (NF-κB) but activates peroxisome proliferator-activated receptor (PPAR). Additionally, cucurbitane-type triterpene glycosides are the main bioactive components of the fruit of M. charantia. Therefore, we investigated the anti-inflammatory activity of 17 cucurbitane-type triterpene glycosides (1-17) isolated from this plant. Their inhibition of NF-κB and activation of PPAR activities in HepG2 cells were measured using luciferase reporter and PPAR subtype transactivation assays. Compounds 6 and 8 were found to inhibit NF-κB activation stimulated by tumor necrosis factor-α (TNFα) in a dose-dependent manner. With 50% inhibition concentration (IC(50)) values of 0.4 μM, compounds 6 and 8 were more potent inhibitors than the positive control, sulfasalazine (IC(50)=0.9 μM). Compounds 4, 6, and 8 also inhibited TNFα-induced expressions of inducible nitric oxide synthase and cyclooxygenase-2 mRNA. However, only compound 13 significantly increased PPARγ transactivation.

Cucurbitane-Type Triterpenes with Anti-proliferative Effects on U937 Cells from an Egyptian Natural Medicine, Bryonia cretica: Structures of New Triterpene Glycosides, Bryoniaosides A and B

The 90% aqueous ethanol extract of an Egyptian natural medicine, the roots of Bryonia cretica L., was found to exhibit a strong inhibitory effect on the proliferation of human leukemia U937 cells. By bioassay-guided fractionation, we isolated two new cucurbitane-type triterpene glycosides, bryoniaosides A and B, were isolated from the roots of Bryonia cretica L. together with 16 known cucurbitane-type triterpenes and glycosides. The chemical structures of bryoniaosides A and B were determined on the basis of chemical and spectroscopic evidence. Effects of principal cucurbitane-type triterpenes (cucurbitacins B, D, E, and J, 23,24-dihydrocucurbitacins B and E, and hexanorcucurbitacin D) on proliferation of the cells were examined. Cucurbitacins B and E showed the greater cytotoxic effects with IC(50) values of 9.2 and 16 nM after 72 h, and their IC(50) values were equivalent to that of camptothecin. An alpha,beta-conjugated ketone moiety at the 22-24-positions and an acetoxy group at the 25-position are essential for the strong activity.

α-Glucosidase Inhibition Properties of Cucurbitane-Type Triterpene Glycosides from the Fruits of <i>Momordica charantia</i>

Fourteen cucurbitane-type triterpene glycosides (1-14) were isolated from a methanol extract of Momordica charantia fruits, including three new compounds, charantosides A-C (1, 5, 6). Their structures were elucidated by chemical and spectroscopic methods. All isolated compounds were evaluated for alpha-glucosidase inhibitory effect. Of which, 12 and 13 showed moderate inhibitory activity against alpha-glucosidase. Whereas, 2, 3, 6-11, and 14 showed weak inhibitory activity, and 1, 4, and 5 were inactive.

Cucurbitane-Type Triterpene Glycosides from the Fruits ofMomordica charantia

Phytochemical investigation of the fruits of Momordica charantia resulted in the isolation and characterization of two new (1 and 2) and eight known cucurbitane-type triterpene glycosides and one cucurbitane-type triterpene. The glycosides (7beta,25-dimethoxycucurbita-5(6),23( E)-dien-19-al 3- O-beta-D-allopyranoside (1); 25-methoxycucurbita-5(6),23(E)-dien-19-ol 3-O-beta-D-allopyranoside (2); momordicosides A, F (1), F (2), G, K, and L; and goyaglycoside-c and goyaglycoside-d) and the triterpene [3 beta,7 beta,25-trihydroxycucurbita-5,23(E)-dien-19-al] were characterized by physical, chemical, and spectroscopic techniques, including 1D- and 2D-NMR as well as by comparison with the reported data.

Cucurbitane-Type Triterpenoids from the Fruits of Momordica charantia and Their Cancer Chemopreventive Effects

Thirteen cucurbitane-type triterpene glycosides, including eight new compounds named charantosides I (6), II (7), III (10), IV (11), V (12), VI (13), VII (16), and VIII (17), and five known compounds, 8, 9, 14, 15, and 18, were isolated from a methanol extract of the fruits of Japanese Momordica charantia. The structures of the new compounds were determined on the basis of spectroscopic methods. On evaluation of these triterpene glycosides and five other cucurbitane-type triterpenes, 1-5, also isolated from the extract of M. charantia fruits, for their inhibitory effects on the induction of Epstein-Barr virus early antigen (EBV-EA) by 12-O-tetradecanoylphorbol-13-acetate (TPA) in Raji cells, these compounds showed inhibitory effects on EBV-EA induction with IC(50) values of 200-409 mol ratio/32 pmol TPA. In addition, upon evaluation of compounds 1-5 for inhibitory effects against activation of (+/-)-(E)-methyl-2[(E)-hydroxyimino]-5-nitro-6-methoxy-3-hexemide (NOR 1), a nitrogen oxide (NO) donor, compounds 1-3 showed moderate inhibitory effects. Compounds 1 and 2 exhibited marked inhibitory effects in both 7,12-dimethylbenz[a]anthracene (DMBA)- and peroxynitrite (ONOO-; PN)-induced mouse skin carcinogenesis tests.

Bioactive Saponins and Glycosides. XXVII. Structures of New Cucurbitane-Type Triterpene Glycosides and Antiallergic Constituents from Citrullus colocynthis

The methanolic extract from the fruit of Citrullus colocynthis showed an inhibitory effect on ear passive cutaneous anaphylaxis reactions as a type I allergic model in mice. From the methanolic extract, two new cucurbitane-type triterpene glycosides, colocynthosides A and B, were isolated together with 17 known constituents. The structures of colocynthosides A and B were elucidated on the basis of chemical and physicochemical evidence. In addition, the principal cucurbitane-type triterpene glycoside, cucurbitacin E 2-O-beta-D-glucopyranoside, and its aglycon, cucurbitacin E, exhibited the antiallergic activity at a dose of 100 and 1.25 mg/kg, p.o., respectively.

Structures of New Cucurbitane-Type Triterpenes and Glycosides, Karavilagenins D and E, and Karavilosides VI, VII, VIII, IX, X, and XI, from the Fruit of Momordica charantia

Two new cucurbitane-type triterpenes, karavilagenins D and E, and six new cucurbitane-type triterpene glycosides, karavilosides VI, VII, VIII, IX, X, and XI, were isolated from the fruit of Momordica charantia L. (Cucurbitaceae) cultivated in Sri Lanka. Their structures were elucidated on the basis of chemical and physicochemical evidence.

Structures of New Cucurbitane-Type Triterpenes and Glycosides, Karavilagenins and Karavilosides, from the Dried Fruit of Momordica charantia L. in Sri Lanka

Three new cucurbitane-type triterpene called karavilagenins A, B, and C and five new cucurbitane-type triterpene glycosides called karavilosides I, II, III, IV, and V were isolated from the dried fruit of Sri Lanka Momordica charantia L. (Cucurbitaceae) together with two known cucurbitane-type triterpenes, 19(R)-methoxy-5beta,19-epoxycucurbita-6,23-dien-3beta,25-diol and 5,19-epoxycucurbita-6,23-diene-3,25-diol, and nine known cucurbitane-type triterpene glycosides, goyaglycosides-b, -c, and -d, and momordicosides F1, F2, G, I, K, and L. The structures of karavilagenins and karavilosides were elucidated on the basis of chemical and physicochemical evidence.

Medicinal foodstuffs. XXI. Structures of new cucurbitane-type triterpene glycosides, goyaglycosides-a, -b, -c, -d, -e, -f, -g, and -h, and new oleanane-type triterpene saponins, goyasaponins I, II, and III, from the fresh fruit of Japanese Momordica charantia L.

Eight cucurbitane-type triterpene glycosides called goyaglycosides-a, -b, -c, -d, -e, -f, -g, and -h and three oleanane-type triterpene saponins termed goyasaponins I, II, and III were isolated from the fresh fruit of Japanese Momordica charantia L. (Cucurbitaceae) together with five known cucurbitane-type triterpene glycosides momordicosides A, C, F1, I, and K. The structures of goyaglycosides and goyasaponins were elucidated on the basis of chemical and physicochemical evidence.