Cochinchinensis Seeds Research Articles

Design of Hepatitis C Protease Inhibitors Based on Knottin Fold

AbstractKnottins are very stable peptides (also called miniproteins) containing approximately 30 amino acid residues. Their structures are stabilized by three disulfide bonds forming a characteristic ‘pseudo‐knotted’ structure. This research was devoted to the design of potential inhibitors of human hepatitis C (HCV) NS3 protease by means of knottin fold using loop grafting, amino acid residues replacements and L/D amino acid epimerization. The initial structure used for design was a trypsin inhibitor from Momordica cochinchinensis seeds, MCOTI‐II. Modifications of the knottin template for optimization of the NS3 protease‐peptide interaction included deletion of several residues from the N‐terminus, replacement of residues in‐ and outside the inhibitor loop and replacement of certain L‐amino acids by their D‐stereoisomers. Stability of modified knottins and their complexes with HCV protease were evaluated by molecular dynamics simulation. Binding energy values for protein‐knottin complexes were calculated by MM‐GBSA method. The designed modified knottin characterized by the highest stability of the complex with HCV NS3 protease, was proposed for further experimental testing.

Effect of Mucuna cochinchinensis seed extract on Alloxan-Induced Diabetic Experimental Rats

Objective: Mucuna cochinchinensis (Fabaceae)is a widely grown twiner that has been used in the traditional medicine for treating many ailments. The objective of the present study was to evaluate the hypoglycemic effects of ethyl acetate extract of M. cochinchinensis seeds on alloxan-induced diabetic rat models. Materials and Methods: M.cochinchinensis seeds were collected and macerated with ethyl acetate to obtain ethyl acetate extract of M. cochinchinensis (EMC). The obtained extract was subjected to preliminary phytochemical analysis using standard protocol and HPLC-MS study to identify the phytoconstituents present. Effect of EMC on parameters like blood glucose and plasma insulin levels were assessed using commercial kits in alloxan-induced experimental rats. Results: Preliminary phytochemical analysis of EMC showed the presence of alkaloids, flavonoids, terpenoids, saponins, tannins and glycosides. HPLC-MS study revealed the presence of 6-C-Pentosyl-8-C-hexosyl apigenin and kaempferol-3-O-rutinoside in EMC. EMC effect on alloxan-induced diabetic ratsblood glucose level on 1st, 7th and 14th day and plasma insulin levels were determined and was found to revert the blood glucose levels significantly (p<0.01). Conclusion: To conclude, EMC has potent efficacy in normalizing blood glucose and serum insulin concentration in alloxan induced diabetic rats.

The legumain McPAL1 from Momordica cochinchinensis is a highly stable Asx-specific splicing enzyme

Legumains, also known as asparaginyl endopeptidases (AEPs), cleave peptide bonds after Asn/Asp (Asx) residues. In plants, certain legumains also have ligase activity that catalyzes biosynthesis of Asx-containing cyclic peptides. An example is the biosynthesis of MCoTI-I/II, a squash family-derived cyclic trypsin inhibitor, which involves splicing to remove the N-terminal prodomain and then N-to-C-terminal cyclization of the mature domain. To identify plant legumains responsible for the maturation of these cyclic peptides, we have isolated and characterized a legumain involved in splicing, McPAL1, from Momordica cochinchinensis (Cucurbitaceae) seeds. Functional studies show that recombinantly expressed McPAL1 displays a pH-dependent, trimodal enzymatic profile. At pH 4 to 6, McPAL1 selectively catalyzed Asp-ligation and Asn-cleavage, but at pH 6.5 to 8, Asn-ligation predominated. With peptide substrates containing N-terminal Asn and C-terminal Asp, such as is found in precursors of MCoTI-I/II, McPAL1 mediates proteolysis at the Asn site and then ligation at the Asp site at pH 5 to 6. Also, McPAL1 is an unusually stable legumain that is tolerant of heat and high pH. Together, our results support that McPAL1 is a splicing legumain at acidic pH that can mediate biosynthesis of MCoTI-I/II. We purport that the high thermal and pH stability of McPAL1 could have applications for protein engineering.

Cytotoxic and anti-inflammatory constituents from Momordica cochinchinensis seeds

Five new lignans mubiesins A − E (1–5), together with twenty-seven known compounds (6–32), were isolated from the cytotoxicity and anti-inflammation portions of Momordica cochinchinensis seeds which were widely used for various tumors and inflammations. Their structures were elucidated by extensive spectroscopic analyses (HR-MS, UV, CD, IR, 1D-NMR, and 2D-NMR). Their cytotoxic and anti-inflammatory activities were evaluated in vitro. Various lignans and saponins showed the significant activities, they could obviously inhibit the growth of tumor cells and the release of NO and TNF-α in RAW 264.7 cells induced by LPS.

DETERMINATION OF TRIACYLGLYCEROLS AND FATTY ACID COMPOSITION OF MOMORDICA COCHINCHINENSIS SEED OIL AND SOME OTHER PLANTS OF THIS GENUS

The oils of Momordica cochinchinensis seeds were collected in 15 regions of Vietnam and studied by reversed-phase high-performance liquid chromatography. Two detectors were used in the work – diode-array detector and mass spectrometric detector with mixed ionization: chemical ionization at atmospheric pressure and ionization by electrospray. It was found that triacylglycerols (TAG) of all oils contain substituents of one dominant acid – α-eleostearic acid, mole fraction of the acid between fatty acid substituents was 58.1–72.4%, thus the seeds of the plant are a valuable raw material for the production of pharmacologically important oil. It was found that the three types of seed oils of Momordica genus (M. charantia, M. cochinchinensis, and M. subangulata) belong to the same type of oil while the seed oil of another species of the genus M. balsamina is characterized by simultaneous biosynthesis of two conjugated octadecatrienoic acids: α-eleostearic and punic. To evaluate the specificity of the TAG types biosynthesis is proposed the parameter of the ration of the experimental and theoretically possible (with equal probability of occupation of different positions in glycerol moiety by acid substituents) TAG mole fractions. It was found that the main oil TAG, di-α-eleostearate-stearate) is synthesized with high specificity.

Studied on the extraction, response surface analysis and antioxidant activity of flavonoids in the Momordia cochinchinensis seeds

This text was mainly studied the extraction flavonoids technology from Momordia cochinchinensis seeds. The optimum extraction condition was as follows: when the ratio of liquid to solid was 20:1, the ethanol concentration was 90% and the extraction time was 2h. Under this condition, the actual average yield of flavonoids could reach 0.363%.

Antiproliferative effect of Momordica cochinchinensis seeds on human lung cancer cells and isolation of the major constituents

Gac, Momordica cochinchinensis (Lour.) Spreng., Cucurbitaceae, is an indigenous South Asian edible fruit and has been used therapeutically in Traditional Chinese Medicine. Previous studies have shown that M. cochinchinensis seed (Momordicae Semen) has various pharmaceutical properties such as antioxidant and anti-ulcer effects as well as contains secondary metabolites with potential anticancer activities such as triterpenoids and saponins. However, its biological activities in cancer have not yet been investigated. In this study, we found that its ethanol extract reduced cell proliferation in four human lung cancer cell lines, A549, H1264, H1299 and Calu-6. Phytochemical investigation of the ethanol extract was carried out, and resulted in isolation of two major saponins, which were identified as gypsogenin 3-O-β-d-galactopyranosyl(1→2)-[α-l-rhamnopyranosyl(1→3)]-β-d-glucuronopyranoside (1) and quillaic acid 3-O-β-d-galactopyranosyl(1→2)-[α-l-rhamnopyranosyl(1→3)]-β-d-glucuronopyranoside (2). Treatment with these isolated compounds (1 and 2) decreased cel1 proliferation in all human lung cancer cell lines tested. In addition, the compounds attenuated primary lung endothelial cell proliferation. Taken together, these findings suggest M. cochinchinensis seeds have antiproliferative activity on human lung cancer cells as well as angiostatic effect on lung endothelial cells.

A comparative study of extraction methods reveals preferred solvents for cystine knot peptide isolation from Momordica cochinchinensis seeds

MCoTI-I and MCoTI-II (short for Momordica cochinchinensisTrypsin Inhibitor-I and -II, respectively) are attractive candidates for developing novel intracellular-targeting drugs because both are exceptionally stable and can internalize into cells. These seed-derived cystine knot peptides are examples of how natural product discovery efforts can lead to biomedical applications. However, discovery efforts are sometimes hampered by the limited availability of seed materials, highlighting the need for efficient extraction methods. In this study, we assessed five extraction methods using M. cochinchinensis seeds, a source of well-characterized cystine knot peptides. The most efficient extraction of nine known cystine knot peptides was achieved by a method based on acetonitrile/water/formic acid (25:24:1), followed by methods based on sodium acetate (20mM, pH5.0), ammonium bicarbonate (5mM, pH8.0), and boiling water. On average, the yields obtained by these four methods were more than 250-fold higher than that obtained using dichloromethane/methanol (1:1) extraction, a previously applied standard method. Extraction using acetonitrile/water/formic acid (25:24:1) yielded the highest number of reconstructed masses within the majority of plant-derived cystine knot peptide mass range but only accounted for around 50% of the total number of masses, indicating that any single method may result in under-sampling. Applying acetonitrile/water/formic acid (25:24:1), boiling water, and ammonium bicarbonate (5mM, pH8.0) extractions either successively or discretely significantly increased the sampling number. Overall, acetonitrile/water/formic acid (25:24:1) can facilitate efficient extraction of cystine-knot peptides from M. cochinchinensis seeds but for discovery purposes the use of a combination of extraction methods is recommended where practical.

Momordica cochinchinensis Seed Extracts Suppress Migration and Invasion of Human Breast Cancer ZR-75-30 Cells Via Down-regulating MMP-2 and MMP-9

Metastases and invasion are the main reasons for oncotherapy failure. Momordica cochinchinensis (Mu Bie Zi in Chinese) had been used for a variety of purposes, and shown anti-cancer action. In this article, we focused on effects on regulation of breast cancer cell ZR-75-30 metastases and invasion by extracts of Momordica cochinchinensis seeds (ESMCs). Effect of ESMCs on ZR-75-30 human breast cancer cells proliferation were evaluated by MTT assay and on invasion and migration by wound-healing and matrigel invasion chamber assays. Expression and protease activity of two matrix metalloproteinases (MMPs), MMP-2 and MMP-9, were analyzed by Western blotting and gelatin zymography, respectively. ESMC revealed strong growth inhibitory effects on ZR-75-30 cells, and effectively inhibited ZR-75-30 cell invasion in a dose-dependent manner. Western blot and gelatin zymography analysis showed that ESMC significantly inhibited the expression and secretion of MMP-2 and MMP-9 in ZR-75-30 cells. ESMC has the potential to suppress the migration and invasion of ZR-75-30 cancer cells, and it might prove to of interest in the development of novel inhibitors for breast cancer.

Pharmacognostical characterization, phytochemical and antimicrobial evaluation of Mucuna cochinchinensis (lour.) Cheval seeds

BackgroudMucuna cochinchinensis is an annual twining herb has been used in the traditional medicine for treating many ailments. The objective of the present study was to carry out the pharmacognostical and phytochemical investigation. Then to evaluate the antimicrobial potency of M. cochinchinensis seed extracts on various pathogens. MethodsThe usual standard methods were followed for preliminary pharmacognostical characterization and phytochemical investigation on the taxon. The methanolic extract (MMC) and ethyl acetate extract (EMC) of M. cochinchinensis were tested against Escherichia coli, Klebsiella pneumoniae, Proteus vulgaris, Bacillus subtilis, Staphylococcus aureus, Aspergillus niger and Candida albicans by disc diffusion method. Results and discussionMicroscopical examination confirmed the taxa selected by the specialized anatomical features seen in hilar region. Phytochemical investigation of the extracts revealed the presence of alkaloids, anthraquinones, flavonoids, phenols, tannins, terpenoids and xanthoprotein. Antimicrobial study results showed promising antibacterial activity of M. cochinchinensis seed extracts against all the bacteria tested. Among these, MMC was found to have more potent inhibitory effect comparing with EMC. EMC showed several degrees of antibacterial properties against E. coli, K. pneumoniae and B. subtilis. Fungi tested were resistant to both the extracts. ConclusionThe extracts of M. cochinchinensis seeds exhibit excellent activity against all the tested bacterial pathogens, which prove the potentiality of the seed extracts for the treatment of various bacterial infections.

Antioxidative effect of a chymotrypsin inhibitor fromMomordica cochinchinensis (Cucurbitaceae) seeds in a primary rat hepatocyte culture

The antioxidative activity of a chymotrypsin-specific potato type I inhibitor from Momordica cochinchinensis (MCoCI) (Cucurbitaceae) has been investigated using the primary rat hepatocyte system. tert-Butyl hydroperoxide (t-BHP) was used to induce oxidative stress. Pretreatment of hepatocytes with MCoCI for 24 h significantly reversed t-BHP-induced cell damage, and the associated glutathione depletion and lipid peroxidation. The activities of glutathione-S-transferase and superoxide dismutase were also increased. These results suggested that MCoCI possessed antioxidative activity which may account for some of the pharmacological effects of Momordica cochinchinensis seeds, the traditional Chinese medicine known as Mubiezhi, from which MCoCI was isolated.

Multiple trypsin inhibitors from Momordica cochinchinensis seeds, the Chinese drug mubiezhi

Five trypsin inhibitors, with N-terminal sequences demonstrating homology to each other and exhibiting a molecular weight of 5100, 4800, 4400, 4100, and 3900, respectively, were isolated from Momordica cochinchinensis seeds with a protocol involving acid extraction, ion exchange chromatography on SP-Sepharose chromatography, and RP-HPLC on a C18 column. Specific inhibitory activity against trypsin was demonstrated by the trypsin isoinhibitors with K i values ranging from 5.3×10 −8 to 1.8×10 −6 M. None of the isoinhibitors could be cleaved by trypsin.

Isolation of a trypsin inhibitor with deletion of N-terminal pentapeptide from the seeds of Momordica cochinchinensis, the Chinese drug mubiezhi

A trypsin inhibitor, MCCTI-1, with a molecular weight of 3479 Da as determined by mass spectrometry, was isolated from Momordica cochinchinensis seeds with a procedure involving extraction with 5% acetic acid, ammonium sulfate precipitation, ion exchange chromatography on CM-Sepharose and reverse-phase high performance liquid chromatography. The sequence of its first 13 N-terminal amino acid residues was ILKKCRRDSDCPG which was about 85% identical with the sequence of trypsin inhibitor MCTI-1 from Momordica charantia Linn. When compared with the sequences of most other squash family trypsin inhibitors, the sequence of MCCTI-1 was characterized by the deletion of a pentapeptide from the N-terminus. Trypsin inhibitors also existed in seeds of some hitherto uninvestigated Cucurbitaceae species.