Triterpenoids from the Stems of Momordica charantia

Two new cucurbitane triterpenes, (23E)‐7β‐methoxycucurbita‐5,23,25‐trien‐3β‐ol ( 1 ) and 23,25‐dihydroxy‐5β,19‐epoxycucurbit‐6‐ene‐3,24‐dione ( 2 ), and a new D : C‐friedooleanane triterpene, 3α‐[(E)‐feruloyloxy]‐D : C‐friedooleana‐7,9(11)‐dien‐29‐oic acid ( 3 ), together with two known D : C‐friedooleanane triterpenes, 3β‐[(E)‐feruloyloxy]‐D : C‐friedooleana‐7,9(11)‐dien‐29‐oic acid ( 4 ) and 3‐oxo‐D : C‐friedooleana‐7,9(11)‐dien‐29‐oic acid ( 5 ), were isolated from the stems of Momordica charantia. The structures of the new compounds 1 – 3 were determined by spectroscopic methods.     

Cucurbitane Triterpenoids from the Fruit Pulp of Momordica charantia and Their Cytotoxic Activity

Two new cucurbitane‐type triterpenes, 25‐methoxycucurbita‐5,23(E)‐diene‐3β,19‐diol ( 1 ) and 7β‐ethoxy‐3β‐hydroxy‐25‐methoxycucurbita‐5,23(E)‐dien‐19‐al ( 2 ), together with three known cucurbitane‐type triterpenes, 3β,7β,25‐trihydroxycucurbita‐5,23(E)‐dien‐19‐al ( 3 ), (23E)‐3β‐hydroxy‐7β,25‐dimethoxycucurbita‐5,23‐dien‐19‐al ( 4 ), and 3β‐hydroxy‐25‐methoxycucurbita‐6,23(E)‐dien‐19,5β‐olide ( 5 ), were isolated from the fruit pulp of Momordica charantia. The structures of two new compounds were elucidated on the basis of 1D and 2D NMR, MS, IR, optical rotation. Among these isolates, compounds 1 , 2 , and 5 showed slight cytotoxic activity against the SK‐Hep 1 cell line with IC₅₀ values of 33.1, 24.3, and 38.7 μM, respectively.     

Cucurbitane‐Type Triterpenoids from Momordica charantia

The six new cucurbitane‐type triterpenoids 1 – 6 , along with the ten known triterpenoids 7 – 16 , were isolated from the vines and leaves of Momordica charantia. The structures of the new compounds were elucidated as (3β,7β,15β,23E)‐3,7,15,25‐tetrahydroxycucurbita‐5,23‐dien‐19‐al ( 1 ), (3β,7β)‐3,7,22,23‐tetrahydroxycucurbita‐5,24‐dien‐19‐al ( 2 ), (3β,7β)‐3,7,23,24‐tetrahydroxycucurbita‐5,25‐dien‐19‐al ( 3 ), (3β,7β,23S)‐3,7,23‐trihydroxycucurbita‐5,24‐dien‐19‐al 7‐β‐D ‐glucopyranoside ( 4 ), (3β,7β,23E)‐cucurbita‐5,23‐diene‐3,7,19,25‐tetrol 7‐β‐D ‐glucopyranoside ( 5 ), and (3β,7β,23E)‐3,7‐dihydroxy‐25‐methoxy‐cucurbita‐5,23‐dien‐19‐al 3‐β‐D ‐allopyranoside ( 6 ), by extensive analyses of their spectral data, as well as by chemical methods.     

A new cucurbitane triterpenoid from Momordica charantia

One new cucurbitane-type triterpenoid saponin, 5b,19-epoxycucurbita-6,23-diene-3b,19,25-triol-3-O-b-D-allopyranoside (1), named momordicoside P was isolated from the fresh fruits of Momordica charantia. The structure of the saponin was elucidated byspectral methods, including 2D-NMR spectra.     

Cucurbitane‐type triterpene glycosides from the fruits of Momordica charantia

The chemical study of Momordica charantia fruits led to the isolation of three new cucurbitane triterpene glycosides, momordicosides U, V, and W (1–3). The structures of these compounds were determined to be (19R, 23R)‐5β, 19‐epoxy‐19‐methoxycucurbita‐6,24‐diene‐3β, 23‐diol 3‐O‐β‐D‐allopyranoside (1), (23R)‐5β, 19‐epoxycucurbita‐6,24‐diene‐3β, 23‐diol 3‐O‐β‐D‐allopyranoside (2), and (19R)‐5β, 19‐epoxy‐19,25‐dihydroxycucurbita‐6,23(E)‐diene‐3β‐ol 3‐O‐β‐D‐glucopyranoside (3), by chemical and spectroscopic methods. Copyright © 2010 John Wiley & Sons, Ltd.     

Two new cucurbitane triterpenoids from Momordica charantia L.

Two new cucurbitane-type triterpenoids,(23E)-5β,19-epoxycucurbita-6,23,25-triene-3β-ol(1) and(19R,23E)-5/β,19-epoxy- 19-ethoxycucurbita-6,23-diene~3β,25-diol(2),together with three known compounds,have been isolated from the fruit of Momordica charantia L.Their structures were determined on the basis of spectral analysis.Their cytotoxic activity was tested on 5 cancer cell lines,MCF-7,HepG2,Dul45,Colon205 and HL-60 by MTT assay.Compounds 1,3 and 4 showed weak cytotoxicity.     

Two New Cucurbitane Triterpenoids from Immature Fruits of Momordica charantia

Two new cucurbitane triterpenoids, kuguacin X ( 1 ) and kuguaglycoside I ( 2 ), together with three known analogs, were isolated from immature fruits of Momordica charantia. By detailed analysis of IR, NMR, and MS data, acid hydrolysis, and comparison with spectroscopic data of known compounds, the new compounds were determined to be (23E)‐5β,19‐epoxycucurbita‐6,23‐diene‐3β,22ξ,25‐triol ( 1 ) and (23E)‐5β,19‐epoxycucurbita‐6,23‐dien‐19‐on‐3β,25‐diol 3‐O‐β‐D ‐allopyranoside ( 2 ).     

One new 19-nor cucurbitane-type triterpenoid from the stems of Momordica charantia

One new 19-nor cucurbitane-type triterpenoid (3β,9β,25-trihydroxy-7β-methoxy-19-nor-cucurbita-5,23(E)-diene) (1), together with other six known cucurbitane-type triterpenoids (2–7), were isolated from the stems of Momordica charantia L. The chemical structure of 1 was elucidated by extensive 1D NMR and 2D NMR (HSQC, HMBC, COSY and ROESY), MS experiments. Using MTT assay, compound 1 exhibited weak cytotoxicity against HL-60, A-549, and SK-BR-3 cell lines with the IC₅₀ values at 27.3, 32.7 and 26.6 μM, respectively.     

Cucurbitane triterpenoids from Momordica charantia

Three new cucurbitane-type triterpenoid saponins, 23-O-beta-D-allopyranosyl-5beta,19-epoxycucurbita-6,24-diene-3beta,22(S),23(S)-triol-3-O-beta-D-glucopyranoside (1), 23-O-beta-D-allopyranosyl-5beta,19-epoxycucurbita-6,24-diene-3beta,22(S),23(S)-triol-3-O-beta-D-allopyranoside (2), and 23-O-beta-D-allopyranosyl-5beta,19-epoxycucurbita-6,24-diene-3beta,19(R), 22(S),23(S)-tetraol-3-O-beta-D-allopyranoside (3), named momordicoside M, N, and O, respectively, along with one known saponin momordicoside L (4), were isolated from the fresh fruits of Momordica charantia. The structures of these saponins were elucidated on the basis of chemical properties and spectral data.     

Bioactives of Momordica charantia as Potential Anti-Diabetic/Hypoglycemic Agents

Momordica charantia L., a member of the Curcubitaceae family, has traditionally been used as herbal medicine and as a vegetable. Functional ingredients of M. charantia play important roles in body health and human nutrition, which can be used directly or indirectly in treating or preventing hyperglycemia-related chronic diseases in humans. The hypoglycemic effects of M. charantia have been known for years. In this paper, the research progress of M. charantia phytobioactives and their hypoglycemic effects and related mechanisms, especially relating to diabetes mellitus, has been reviewed. Moreover, the clinical application of M. charantia in treating diabetes mellitus is also discussed, hoping to broaden the application of M. charantia as functional food.     

Four New Cucurbitacins from the Fruit of Momordica charantia

Four new 5β,19‐epoxycucurbitacins, kuguacins T–W ( 1 – 4 , resp.), along with nine known cucurbitane derivatives, 5 – 13 , were obtained from the fresh fruit of Momordica chrantia. Structures of the new metabolites were elucidated as 5β,19‐epoxy‐25‐hydroxycucurbitane‐3,7,23‐trione ( 1 ), 5β,19‐epoxy‐3,7‐dioxo‐23,24,25,26,27‐pentanorcucurbitan‐22‐oic acid ( 2 ), 5β,19‐epoxy‐3β‐hydroxycucurbit‐24‐ene‐7,23‐dione ( 3 ), and 5β,19‐epoxy‐25‐hydroxycucurbit‐23‐ene‐3,7‐dione ( 4 ), by extensive spectroscopic investigations, which were confirmed by a single‐crystal X‐ray diffraction analyses in the case of compound 4 .     

Inhibitory Effects of Cucurbitane-Type Triterpenoids from Momordica charantia Fruit on Lipopolysaccharide-Stimulated Pro-Inflammatory Cytokine Production in Bone Marrow-Derived Dendritic Cells

The bitter melon, Momordica charantia L., was once an important food and medicinal herb. Various studies have focused on the potential treatment of stomach disease with M. charantia and on its anti-diabetic properties. However, very little is known about the specific compounds responsible for its anti-inflammatory activities. In addition, the in vitro inhibitory effect of M. charantia on pro-inflammatory cytokine production by lipopolysaccharide (LPS)-stimulated bone marrow-derived dendritic cells (BMDCs) has not been reported. Phytochemical investigation of M. charantia fruit led to the isolation of 15 compounds (1−15). Their chemical structures were elucidated spectroscopically (one- and two-dimensional nuclear magnetic resonance) and with electrospray ionization mass spectrometry. The anti-inflammatory effects of the isolated compounds were evaluated by measuring the production of the pro-inflammatory cytokines interleukin IL-6, IL-12 p40, and tumor necrosis factor α (TNF-α) in LPS-stimulated BMDCs. The cucurbitanes were potent inhibitors of the cytokines TNF-α, IL-6, and IL-12 p40, indicating promising anti-inflammatory effects. Based on these studies and in silico simulations, we determined that the ligand likely docked in the receptors. These results suggest that cucurbitanes from M. charantia are potential candidates for treating inflammatory diseases.     

Momordica charantia Extract Protects against Diabetes-Related Spermatogenic Dysfunction in Male Rats: Molecular and Biochemical Study

More than 90% of diabetic patients suffer from sexual dysfunction, including diminished sperm count, sperm motility, and sperm viability, and low testosterone levels. The effects of Momordica charantia (MC) were studied by estimating the blood levels of insulin, glucose, glycosylated hemoglobin (HbA1c), testosterone (TST), follicle-stimulating hormone (FSH), and luteinizing hormone (LH) in diabetic rats treated with 250 and 500 mg/kg b.w. of the total extract. Testicular antioxidants, epididymal sperm characteristics, testicular histopathology, and lesion scoring were also investigated. Testicular mRNA expression of apoptosis-related markers such as antiapoptotic B-cell lymphoma-2 (Bcl-2) and proapoptotic Bcl-2-associated X protein (Bax) were evaluated by real-time PCR. Furthermore, caspase-3 protein expression was evaluated by immunohistochemistry. MC administration resulted in a significant reduction in blood glucose and HbA1c and marked elevation of serum levels of insulin, TST, and gonadotropins in diabetic rats. It induced a significant recovery of testicular antioxidant enzymes, improved histopathological changes of the testes, and decreased spermatogenic and Sertoli cell apoptosis. MC effectively inhibited testicular apoptosis, as evidenced by upregulation of Bcl-2 and downregulation of Bax and caspase-3. Moreover, reduction in apoptotic potential in MC-treated groups was confirmed by reduction in the Bax/Bcl-2 mRNA expression ratio.     

Antimicrobial activity and agricultural properties of bitter melon (Momordica charantia L.) grown in northern parts of Turkey: a case study for adaptation

This study was designed to determine the adaptation capability of bitter melon (Momordica charantia L.), which is widely grown in tropical and subtropical climates, in northern parts of Turkey. In this study, plant height, number of fruits, fruit length, fruit width, number of seeds and fruit weight of bitter melon grown in field conditions were determined. The antimicrobial effect of the ethanol extract of fruit and seeds against Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus, Salmonella typhi, Aspergillus niger and Candida albicans microorganisms was tested in vitro by the disc diffusion method. In conclusion, plant height (260 cm), number of fruits (16 per plant), number of seeds (30.2 per fruit), fruit width (3.8 cm), fruit length (10.6 cm) and fruit weight (117.28 g fruit^? 1) were determined; fruits were found to have antimicrobial activity against A. niger; oil and seeds were found to have antimicrobial activity against A. niger and E. coli.     

Comparison of antioxidant capacities and antioxidant components of commercial bitter melon (Momordica charantia L.) products

In this study, the total phenolic contents and total antioxidant capacities of some commercial bitter melon products (powder, packaged powder, capsule, paste in olive oil), and of unripe and ripe fruits were determined by spectrophotometric and chromatographic methods. The total antioxidant capacities of unripe and ripe bitter melon samples, determined by using the CUPRAC (cupric reducing antioxidant capacity assay) and ABTS (2,2′-azino-bis(3-ethylbenzthiazolin-6-sulfonic acid))/HRP (horseradish peroxidase) methods, were 42.5 and 36.3 µmol TRE (Trolox equivalent) g–1, and 8.7 and 7.0 µmol TRE g–1, respectively. The TAC (total antioxidant capacity) order of the studied samples using the same 2 methods were determined as follows: capsule (CUPRAC value, 140.8; ABTS/HRP value, 143.6 µmol TRE g–1) > packaged powder (129.6; 126.1) > powder (52.3; 64.3) > unripe fruit (42.5; 36.3) > paste in olive oil (17.6; 14.4) > ripe fruit (8.7; 7.0). The order of phenolic content was found as follows: unripe fruit (193.2 µmol GAE (gallic acid equivalent) g-1) > capsule (162.0) > packaged powder (160.6) > powder (83.6) > paste in olive oil (38.3) > ripe fruit (14.6).     

Natural Compound 3β,7β,25-trihydroxycucurbita-5,23(E)-dien-19-al from Momordica charantia Acts as PPARγ Ligand

Momordica charantia is a popular vegetable associated with effective complementary and alternative diabetes management in some parts of the world. However, the molecular mechanism is less commonly investigated. In this study, we investigated the association between a major cucurbitane triterpenoid isolated from M. charantia, 3β,7β,25-trihydroxycucurbita-5,23(E)-dien-19-al (THCB) and peroxisome proliferator activated receptor gamma (PPARγ) activation and its related activities using cell culture and molecular biology techniques. In this study, we report on both M. charantia fruit crude extract and THCB in driving the luciferase activity of Peroxisome Proliferator Response Element, associated with PPARγ activation. Other than that, THCB also induced adipocyte differentiation at far less intensity as compared to the full agonist rosiglitazone. In conjunction, THCB treatment on adipocytes also resulted in upregulation of PPAR gamma target genes expression; AP2, adiponectin, LPL and CD34 at a lower magnitude compared to rosiglitazone’s induction. THCB also induced glucose uptake into muscle cells and the mechanism is via Glut4 translocation to the cell membrane. In conclusion, THCB acts as one of the many components in M. charantia to induce hypoglycaemic effect by acting as PPARγ ligand and inducing glucose uptake activity in the muscles by means of Glut4 translocation.     

Anti-Aging Effect of Momordica charantia L. on d-Galactose-Induced Subacute Aging in Mice by Activating PI3K/AKT Signaling Pathway

Anti-aging is a challenging and necessary research topic. Momordica charantia L. is a common edible medicinal plant that has various pharmacological activities and is often employed in daily health care. However, its anti-aging effect on mice and the underlying mechanism thereof remain unclear. Our current study mainly focused on the effect of Momordica charantia L. on d-galactose-induced subacute aging in mice and explored the underlying mechanism. UHPLC-Q-Exactive Orbitrap MS was applied to qualitatively analyze the chemical components of Momordica charantia L. ethanol extract (MCE). A subacute aging mice model induced by d-galactose (d-gal) was established to investigate the anti-aging effect and potential mechanism of MCE. The learning and memory ability of aging mice was evaluated using behavioral tests. The biochemical parameters, including antioxidant enzyme activity and the accumulation of lipid peroxides in serum, were measured to explore the effect of MCE on the redox imbalance caused by aging. Pathological changes in the hippocampus were observed using hematoxylin and eosin (H&E) staining, and the levels of aging-related proteins in the PI3K/AKT signaling pathway were assessed using Western blotting. The experimental results demonstrated that a total of 14 triterpenoids were simultaneously identified in MCE. The behavioral assessments results showed that MCE can improve the learning and memory ability of subacute mice. The biochemical parameters determination results showed that MCE can improve the activity of antioxidant enzymes and decrease the accumulation of lipid peroxides in aging mice significantly. Furthermore, aging and injury in the hippocampus were ameliorated. Mechanistically, the results showed a significant upregulation in the protein expression of P-PI3K/PI3K and P-AKT/AKT (p < 0.01), as well as a significant reduction in cleaved caspase-3/caspase-3, Bax and P-mTOR/mTOR (p < 0.01). Our results confirm that MCE could restore the antioxidant status and improve cognitive impairment in aging mice, inhibit d-gal-induced apoptosis by regulating the PI3K/AKT signaling pathway, and rescue the impaired autophagy caused by mTOR overexpression, thereby exerting an anti-aging effect.     

Eight New Cucurbitane Glycosides,Kuguaglycosides A – H,from the Root of Momordica charantia L.

Eight new cucurbitane glycosides, kuguaglycosides A–H ( 1 – 8 , resp.), together with five known analogues, 3β,23‐dihydroxycucurbita‐5,24‐dien‐7β‐yl β‐D ‐glucopyranoside ( 9 ), karaviloside III ( 10 ), karaviloside V ( 11 ), karaviloside XI ( 12 ), and momordicoside K ( 13 ), were isolated from the root of Momordica charantia L. The structures of the new compounds were determined on the basis of spectroscopic and chemical methods.     

Biotransformation of p‐Coumaric Acid (=(2E)‐3‐(4‐Hydroxyphenyl)prop‐2‐enoic Acid) by Momordica charantia Peroxidase

LC/MS³‐Guided biotransformation of p‐coumaric acid (=(2E)‐3‐(4‐hydroxyphenyl)prop‐2‐enoic acid; CA) with H₂O₂/Momordica charantia peroxidase at pH 5.0 and 45° in the presence of acetone has resulted in the isolation of three CA trimers, triCA1 ( 1 ), triCA2 (trans‐ 2 ), and triCA3 (cis‐ 2 ), and seven CA dimers, diCA1–diCA7, i.e., 3 – 9 , among which seven (triCA1–triCA3 and diCA1–diCA4) are new compounds and three (diCA5–diCA7) are known compounds. The structures were established by 2D‐NMR such as HSQC, HMBC, and NOESY measurements. The possible mechanism for the formation of the products is also discussed (Schemes 1–3). This is the first time that the biotansformation of p‐coumaric acid catalyzed by peroxidase in vitro was achieved. Compounds triCA3 (cis‐ 2 ), diCA1 ( 3 ), diCA5 ( 7 ), and diCA7 ( 9 ) exhibit a stronger antioxidative activity than the parent CA.     

Characterization of Antioxidant Activity of Momordica Charantia Fruit by Infrared-Based Fingerprinting

Momordica charantia is widely consumed edible fruit. The food and pharmaceutical industries use it as a natural antioxidant. However, the quality control of M. charantia-based medicinal products is questionable due to the complexity of metabolites in this fruit. Hence, this study has developed a statistical model in predicting the antioxidant value through the 2, 2-diphenyl-1 picrylhydrazyl radical scavenging activity and ferric reducing antioxidant power based on infrared spectroscopy with attenuated total reflectance. This technique was reliably used for quality control. Six ethanol extracts (0, 20, 40, 60, 80, and 100% in water) of this plant’s fruit were prepared. The radical scavenging and ferric reducing antioxidant power activities were measured and the chemical profiling of the extracts was fingerprinted by infrared spectroscopy between 4,000 and 600?cm^?1 at a resolution of 4?cm^?1. Statistical analysis was developed by correlating the bioactivity and infrared spectra of each extract using orthogonal partial least square discriminant analysis. The C–N, C?O, C–O, C–H, and OH infrared signals were positively correlated with biological activity. The antioxidant activity of the fruit of M. charantia may be due to the presence of several antioxidants that work synergistically.