[Biotransformation of mogroside III by human intestinal bacteria]

OBJECTIVE

To investigate the biotransformation of mogroside III, one of the main chemical constituent in the fruits of Momordica grosvenori Swingle, by the crude enzymes of human intestinal bacteria, and determine the structure of biotransformation products and provide scientific basis for absorption evaluation of primary mogroside III in human intestine.

METHODS

The mogroside III was incubated with crude enzymes of human intestinal bacteria under the anaerobic environment and 37 degrees C condition to transform mogroside III. The biotransformation products were isolated and purified by silica gel column chromatography, and structurally determined by infra-red (IR) and nuclear magnetic resonance (NMR) spectrometry and mass spectroscopy (MS) techniques.

RESULTS

Mogroside III was converted to mogroside II(A1) and mogrol by successive deglycosylation at C-3 of the glucosyl group and C-24 of the gentiobiosyl group.

CONCLUSION

The human intestinal bacteria showed potent ability to transform mogroside III to release secondary glycoside mogroside II(A1) and aglycone mogrol.

[Study on quantitative assessment of Siraitia grosvenorii germplasms by general index]

OBJECTIVE

To establish a weight-marking method and evaluate Siraitia grosvenorii germplasms.

METHOD

The characters of 21 kinds of S. grosvenorii germplasms in the field and the lab were analyzed, seven important characters were selected to weight the marks. A general evaluation index was made and used to evaluate S. grosvenorii germplasms.

RESULT

The evaluation result of 21 kinds of S. grosvenorii germplasms by the weight-marking method was consistent with production practice. Meanwhile, the new variety Yongqing No. 1 and major cultivars were the superior germplasms.

CONCLUSION

A rational technique system of evaluating S. grosvenorii germplasms was established, and the superior germplasms were selected.

Effect of Momordica grosvenori on oxidative stress pathways in renal mitochondria of normal and alloxan-induced diabetic mice. Involvement of heme oxygenase-1

BACKGROUND

Oxidative stress plays an important role in the pathogenesis of diabetes and diabetic nephropathy. Momordica grosvenori (MG), a traditional medicinal herb used as substitute sugar for obese and diabetes, exhibits anti-oxidative activity in vitro.

AIM OF THE STUDY

This study investigated the effect of MG on renal mitochondrial lipid peroxidation, anti-oxidative defense system, and a potent oxidative stress-responsive protein, heme oxygenase-1 (HO-1) of nondiabetic and alloxan-diabetic mice in different stages of diabetes.

METHODS

Male Balb/c mice were rendered diabetic by a single intra-peritoneal injection of alloxan (200 mg/kg), while control mice received sham saline injection. Control and diabetic mice were further subdivided according to their treatments: control (saline), low dose MG (150 mg/kg) and high dose MG (300 mg/kg), which were administered immediately after confirmation of hyperglycemia by gavage daily over an 8-week period. Mice were killed by cervical dislocation at 4th and 8th week, respectively, and serum and renal tissues were harvested. Serum glucose, lipid profile and renal function were evaluated; renal homogenate were subjected to determination of malondialdehyde (MDA) and glutathione (GSH) concentration, manganese superoxide dismutase (Mn-SOD), glutathione peroxidase (GSH-Px) and HO-1 activities, together with Mn-SOD and HO-1 mRNA expression; paraffin-embedded renal tissues was used for routine histopathological examination.

RESULTS

Short-term diabetes caused hyperglycemia and intensified oxidative stress in renal mitochondrial demonstrated by higher MDA and lower GSH levels than control group, accompanied by increased mRNA expression and activity of HO-1 and Mn-SOD, and augmented GSH-Px activity. Low dose of MG administration ameliorated hyperglycemia, inhibited HO-1 and Mn-SOD mRNA expression and reduced HO-1, Mn-SOD, GSH-Px activities. Diabetic mice did not demonstrate early symptoms of diabetic nephropathy until 8th week, characterized by hyperglycemia, hyperlipidemia, and renal damage. A progressive increment in MDA level and decrease in GSH level, as well as reduced mRNA expression and activity of Mn-SOD and HO-1 in the kidney were observed. Low dose of MG attenuated diabetic nephropa- thy symptoms partially, inhibited lipid peroxidation, up-regulated HO-1 and Mn-SOD mRNA expression, and increased HO-1 activity. Conclusions The study confirmed the involvement of oxidative stress in the development of diabetes mediated by the pro- and antioxidant role of HO-1, and pointed to the possible anti-oxidative mechanism of the anti-diabetic and nephroprotective action of MG.

The cyclic cystine knot miniprotein MCoTI-II is internalized into cells by macropinocytosis

The cyclotides are macrocyclic knotted proteins characterized by a compact topology and exceptional stability. Accordingly it has been hypothesized that they may be useful as protein engineering frameworks for the stabilization and delivery of bioactive peptide sequences. This study examined the internalization of cyclotides into mammalian cells, a vital step for the delivery of bioactive peptide sequences to intracellular targets. Although the entry of various linear peptides into cells has been reported previously, this is the first report of internalization of a macrocyclic peptide. Cell uptake was examined for representatives of two cyclotide subfamilies; the first was MCoTI-II, a member of the trypsin inhibitor subfamily, which was internalized by a macrophage and breast cancer cell line and the second, the prototypic cyclotide kalata B1 from the Möbius subfamily, which remained extracellular. Biotin labeled MCoTI-II entered macrophages by macropinocytosis, resulting in vesicular encapsulation without trafficking to lysosomes for degradation. The ready uptake, coupled with low cytotoxicity, indicates that MCoTI-II has the potential to transport grafted bioactivities to intracellular targets, making it a potentially valuable framework in drug design applications.

A natural sweetener, Momordica grosvenori, attenuates the imbalance of cellular immune functions in alloxan-induced diabetic mice

Momordica grosvenori (MG), a traditional medicinal herb in China used as a substitute sugar for obese and diabetic patients, exhibited an enhancement of immunity. Heme oxygenase-1 (HO-1) is among the acute phase proteins that play an important role in the inflammatory process and have antiinflammatory activities with their antioxidant properties. The hypothesis that MG could modulate an imbalance of the cellular immune system and prevent the progression of diabetes mellitus, via induction of HO-1 protein expression was investigated. Diabetes was induced in male Balb/c mice by intraperitoneal injection of alloxan (200 mg/kg). The mice were randomly assigned to non-diabetic and diabetic groups, and further subdivided according to their treatments: control (distilled water), low dose MG (150 mg/kg) and high dose MG (300 mg/kg), which were administered by gavage in 24 h cycles over a 30 day period. MG administration effectively regulated the immune imbalance in diabetic mice, principally by upregulating the CD4(+) T lymphocyte subsets, and remodeling the intracellular cytokine profiles (reducing the expression of pro-inflammatory Th1 cytokines towards a beneficial Th2 pattern), ascribed to its induction and upregulation of HO-1. In conclusion, MG exhibited antidiabetic effects and may be used as a new natural drug for the treatment of diabetes.

Cochinin B, a Novel Ribosome-Inactivating Protein from the Seeds of Momordica cochinchinensis

Cochinin B, a novel ribosome-inactivating protein (RIP) with a molecular weight of 28 kDa, was purified from the seeds of Momordica cochinchinensis (Cucurbitaceae). The isolation procedure entailed ammonium sulfate precipitation, cation-exchange chromatography on SP Sepharose column and size-exclusion chromatography on Superdex 75 column with a fast protein liquid chromatography (FPLC) system. The first twenty N-terminal amino acid residues of Cochinin B showed homology to type I RIPs from other Momordica species. The purified Cochinin B displayed a strong inhibitory activity on protein synthesis in the cell-free rabbit reticulocyte lysate system with IC50 of 0.36 nM. Furthermore, it exhibited N-glycosidase activity and cytotoxicity against Vero cell line with IC50 higher than 1540 nM. Interestingly, Cochinin B manifested strong anti-tumor activities on human cervical epithelial carcinoma (HeLa), human embryonic kidney (HEK293) and human small cell lung cancer (NCI-H187) cell lines with IC50 of 16.9, 114 and 574 nM, respectively.

[Chemical constituents of unsaponifiable matter from seed oil of Momordica cochinchinensis]

OBJECTIVE

To study the chemical constituents of unsaponifiable matter from the seed oil of Momordica cochinchinensis.

METHOD

The fatty oil from the seeds of M. cochinchinensis was extracted with petroleum ether, and the saponification was carried out with potassium hydroxide. The unsaponifiable matter was isolated and purified by silica gel column chromatography, and the structures of their constituents were elucidated by means of IR, MS, 1H-NMR, and authentic chemicals.

RESULT

Karounidiol (1), isokarounidiol (2), 5-dehydrokarounidiol (3), 7-oxodihydrokarounidiol (4), beta-sitosterol (5), stigmast-7-en-3beta-ol (6), and stigmast-7,22-dien-3beta-ol (7) were elucidated.

CONCLUSION

These compounds were found in this plant for the first time.

Subchronic 90-day oral (Gavage) toxicity study of a Luo Han Guo mogroside extract in dogs

A combined 28-day and 90-day oral (Gavage) study was conducted in male and female dogs to investigate the safety of PureLo, a non-caloric sweetener derived from the Chinese fruit Luo Han Guo, which achieves its sweetness from the presence of triterpene glycosides known as mogrosides. Three dogs of each sex were administered 10 mL/kg bw/day of either an aqueous solution providing 3000 mg/kg bw/day of PureLo or distilled water for either 28 days or 90 days. Measurements included clinical observations, body weight, food consumption, hematology, blood chemistry, urinalysis, gross necropsy, organ weight, and histopathology. There were no significant adverse effects on any of these measures. Based on the lack of toxicological effects in the study, the NOAEL for PureLo is 3000 mg/kg bw/day when administered to dogs by Gavage for 90 consecutive days.

Immunomodulatory activity of a chymotrypsin inhibitor from Momordica cochinchinensis seeds

Serine protease inhibitors are widely distributed in the plant kingdom. Many of them have been purified and characterized from different species. While the physicochemical properties of these protease inhibitors have been extensively investigated, their biological effects, e.g. immunomodulatory effect, remain relatively unexplored. Recently, we isolated a chymotrypsin-specific inhibitor (MCoCI) from the seeds of Momordica cochinchinensis (Lour) Spreng (Family Cucurbitaceae), the traditional Chinese medicine known as Mubiezhi, which has been used as an antiinflammatory agent. In the present study, the effects of MCoCI on different types of cells of the immune system, including splenocytes, splenic lymphocytes, neutrophils, bone marrow cells and macrophages, were investigated. MCoCI was shown to possess immuno-enhancing and antiinflammatory effects. MCoCI could stimulate the proliferation of different cells of the immune system, e.g. splenocytes, splenic lymphocytes and bone marrow cells, in a manner comparable to that of Concanavalin A. Moreover, MCoCI could also suppress the formation of hydrogen peroxide in neutrophils and macrophages. These immunomodulatory effects may explain some of the therapeutic actions of Mubiezhi.

Anti-diabetic potentials of Momordica charantia and Andrographis paniculata and their effects on estrous cyclicity of alloxan-induced diabetic rats

Momordica charantia and Andrographis paniculata are the commonly used herbs by the diabetic patients in Pampanga, Philippines. While the anti-diabetic potential of Momordica charantia is well established in streptozocin- or alloxan-induced diabetic animals, the anti-diabetic potential of Andrographis paniculata in alloxan-induced diabetic rat is not known. Neither the effects of these herbs on estrous cyclicity of alloxan-induced diabetic rats are elucidated. Thus, in these experiments, Momordica charantia fruit juice or Andrographis paniculata decoction was orally administered to alloxan-induced diabetic rats. Rats that were treated with Momordica charantia and Andrographis paniculata had higher body weight (BW) compared with diabetic positive control (P < 0.01) from day 22 to day 27 (D27) but exhibited lower BW than the non-diabetic control (P < 0.05). These rats had lower feed (P < 0.05) and liquid intakes (P < 0.01) compared with diabetic positive control from day 17 to D27, but similar with the non-diabetic control. The blood glucose levels in these groups were significantly reduced from day 12 to D27 compared with diabetic positive control (P < 0.01), however, comparable with non-diabetic control. The diabetic positive control had extended mean estrous cycles (8 days) compared to Momordica charantia and Andrographis paniculata-treated diabetic rats (5 days; P < 0.05). Our results suggest that the anti-diabetic potentials of Momordica charantia and Andrographis paniculata could restore impaired estrous cycle in alloxan-induced diabetic rats.

Barnase Fusion as a Tool to Determine the Crystal Structure of the Small Disulfide-rich Protein McoEeTI

We present a fusion system suited to determine the crystal structure of small disulfide-rich proteins. McoEeTI, a hybrid inhibitor cystine knot microprotein, was produced as a soluble fusion to a catalytically inactive variant of the RNAse barnase in Escherichia coli. Functioning as a versatile tag, barnase facilitated purification, crystallization and high-resolution structure determination. Flexibility of the linker region allows for different relative orientations of barnase and the fusion partner in two crystallographically independent molecules and may thereby facilitate crystal packing. Nevertheless, the linker region is well ordered in both molecules. This system may prove more generally useful to determine the crystal structure of peptides and small proteins.

Effect of graded doses of Momordica charantia seed extract on rat sperm: scanning electron microscope study

Morphological changes in sperm of albino rats observed under scanning electron microscopy illustrate the disturbance in the plasma membrane as well as in the acrosomal membrane on treatment with effect of graded doses of alcohol seed extract from Momordica charantia. Considerable changes in the shape and size of the sperm head were observed, with the middle region of the sperm head being slightly constricted dorsoventrally. Most sperm appeared morphologically abnormal in the mid-region of the tail, with formation of a balloon-like cytoplasmic droplet. The results of this study suggest that such effects may have resulted from a general disturbance in proteins and an alteration in the cauda epididymal milieu, probably due to androgen deficiency consequent to the anti-androgenic property of Momordica charantia seeds.

[The biotransformation of kaempferitrin by human intestinal flora]

AIM

To study the biotransformation of kaempferitrin, a major chemical principle of the fruits of Siraitia grosvenori (Swingle) C. Jeffery, with human intestinal flora.

METHODS

The kaempferitrin was incubated with human intestinal flora. The biotransformation products were isolated and purified by chromatographic methods and the structures were determined by spectroscopic techniques.

RESULTS

Kaempferitrin was converted into kaempferol 3-O-alpha-L-rhamnoside (afzelin, I) , kaempferol 7-O-alpha-L-rhamnoside (II), kaempferol (III) and p-hydroxybenzoic acid (IV) by human intestinal flora. rhamnoside (II), kaempferol (III) and p-hydroxybenzoic acid (IV) by human intestinal flora.

CONCLUSION

The structure of kaempferitrin can be biotransformatedly converted by human intestinal flora.

The in vitro and in vivo antimalarial activity of Cardiospermum halicacabum L. and Momordica foetida Schumch. Et Thonn

Two plants Cardiospermum halicacabum L. and Momordica foetida Schumch. Et Thonn traditionally used to treat symptoms of malaria in parts of East and Central Africa were screened for in vitro and in vivo antimalarial activity. Using the nitro tetrazolium blue-based parasite lactate dehydrogenase assay as used by [Makler, M.T., Ries, J.M., Williams, J.A., Bancroft, J.E., Piper, R.C., Gibbins, B.L., Hinrichs, D.J., 1993. Parasite lactate dehydrogenase as an assay for Plasmodium falciparum drug sensitivity. American Journal of Tropical Medicine and Hygiene 48, 739-741], water extracts from the two plants were found to have weak in vitro antiplasmodial activity with 50% inhibitory concentrations (IC50s) greater than 28.00 microg/ml. In vivo studies of water extracts from the two plants showed that Momordica foetida given orally in the dose range 10, 100, 200 and 500 mg/kg twice daily prolonged survival of Plasmodium berghei (Anka) infected mice from 7.0+/-1.8 to 17.9+/-1.8 days. The water extract of Cardiospermum halicacabum L was toxic to mice, none surviving beyond day 4 of oral administration, with no evidence of protection against Plasmodium berghei malaria. The study emphasizes the discrepancy that might be found between in vitro and in vivo testing of plant-derived antimalarial extracts and the need to consider in vitro antiplasmodial data with this in mind. Further studies on Momordica foetida as a source of an antimalarial remedy are indicated on the basis of these results.

Antidiabetic activity of Momordica charantia seeds on streptozotocin induced diabetic rats

The present study was aimed to evaluate the hypoglycemic efficacy in an aqueous extract of seeds of two varieties, namely a country and a hybrid variety of Momordica charantia (MCSEt1 and MCSEt2) respectively in streptozotocin (STZ) induced diabetic rats. STZ-induced diabetic rats were treated with aqueous extracts of MCSEt1 and t2 for a period of 30 days. MCSEt1 and t2 extract treatment to diabetic rats resulted in a significant reduction in blood glucose, glycosylated hemoglobin, lactate dehydrogenase, glucose-6-phosphatase, fructose-1,6-bisphosphatase and glycogen phosphorylase, and a concomitant increase in the levels of hemoglobin, glycogen and activities of hexokinase and glycogen synthase. These results clearly show the antidiabetic properties of Momordica charantia. Both the varieties showed safe and significant hypoglycemic effects which were more pronounced in MCSEt1 compared to MCSEt2 and glibenclamide.

Inhibition of tumor growth and angiogenesis by water extract of Gac fruit (Momordica cochinchinensis Spreng)

The antitumor activity of the crude water extract from Gac fruit (Momordica cochinchinensis) was investigated in vivo and in vitro. A water extract prepared from 0.75 and 0.25 mg dry weight of Gac fruit per gram body weight was given daily to Balb/c mice (n=15/group). The water extract inhibited the growth of the colon 26-20 adenocarcinoma cell line, transplanted in Balb/c mice, reducing wet tumor weight by 23.6%. Histological and immunohistochemical results indicated that Gac water extract reduced the density of blood vessels around the carcinoma. The water extract also produced a marked suppression of cell proliferation in colon 26-20 and HepG2 cells. Cell cycle analysis demonstrated a significant accumulation of cells in the S phase by water extract. Immunoblotting showed that cyclin A, Cdk2, p27waf1/Kip1 were down-regulated, whereas the protein level of p21waf1/Cip1 was not decreased. Treatment of colon 26-20 cells with Gac extract induced necrosis rather than apoptosis. The antitumor component was confirmed as a protein with molecular weight of 35 kDa, retained in the water-soluble high molecular weight fraction. Thus, the bioactive antitumor compound in Gac extract is a protein, which is distinct from lycopene, another compound in Gac fruit with potential antitumor activity.

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 Ki values ranging from 5.3 x 10(-8) to 1.8 x 10(-6) M. None of the isoinhibitors could be cleaved by trypsin.

Fatty acid and carotenoid composition of gac (Momordica cochinchinensis Spreng) fruit

In this study, we analyzed fatty acid and carotenoid composition of fruit tissues, including seed (which are surrounded by a bright red, oily aril) of Momordica cochinchinensis Spreng, known as gac in Vietnam. Carotenoid content was analyzed by reversed-phase HPLC, using a C(30) column and a method separating cis- and trans-isomers of the major carotenoids in this fruit. Mean values obtained in aril tissues were 1342 microg trans-, 204 microg cis-, and 2227 microg total lycopene; 597 microg trans-, 39 microg cis-, and 718 microg total beta-carotene; and 107 microg alpha-carotene/g FW. Mesocarp contained 11 microg trans-, 5 microg cis-beta-carotene/g FW, trace amounts of alpha-carotene, and no lycopene. Gac aril contained 22% fatty acids by weight, composed of 32% oleic, 29% palmitic, and 28% linoleic acids. Seeds contained primarily stearic acid (60.5%), smaller amounts of linoleic (20%), oleic (9%), and palmitic (5-6%) acids, and trace amounts of arachidic, cis-vaccenic, linolenic, and palmitoleic, eicosa-11-enoic acids, and eicosa-13-enoic (in one fruit only) acids.

Anticarcinogenic activity of natural sweeteners, cucurbitane glycosides, from Momordica grosvenori

To search for cancer chemopreventive agents from natural resources, many phytochemicals and food additives have been screened. Consequently, two natural sweeteners, mogroside V and 11-oxo-mogroside V isolated from the fruits of Momordica grosvenori, exhibited strong inhibitory effect on the primary screening test indicated by the induction of Epstein-Barr virus early antigen (EBV-EA) by a tumor promoter, 12-O-tetradecanoylphorbol-13-acetate (TPA). These sweet glycosides, having cucurbitane triterpenoid aglycon, exhibited the significant inhibitory effects on the two-stage carcinogenesis test of mouse skin tumors induced by peroxynitrite (ONOO-) as an initiator and TPA as a promoter. Further, 11-oxo-mogroside V also exhibited the remarkable inhibitory effect on two-stage carcinogenesis test of mouse skin tumor induced by 7,12-dimethylbenz[a]anthracene (DMBA) as an initiator and TPA as a promoter.

A method of preserving and testing the acceptability of gac fruit oil, a good source of beta-carotene and essential fatty acids

Gac fruit (Momordica cochinchinensis Spreng) is indigenous to Vietnam and other countries in Southeast Asia. Its seed pulp contains high concentrations of carotenoids, especially the provitamin A, beta-carotene. In northern Vietnam, gac fruits are seasonal and are mainly used in making a rice dish called xoi gac. The purpose of this study was to develop a method to collect and preserve gac fruit oil, to evaluate the nutritional composition of the oil, and to assess the acceptability of the gac oil by typical Vietnamese homemakers. One hundred women participated in training to learn how to prepare the fruits and operate the oil press. The women also participated in a survey of gac fruit use and their habitual use of animal fat and vegetable oil. Among all the participants in the training and surveys, 35 women actually produced oil from gac fruits grown in the village, using manual oil presses and locally available materials. The total carotene concentration in gac fruit oil was 5,700 micrograms/ml. The concentration of beta-carotene was 2,710 micrograms/ml. Sixty-nine percent of total fat was unsaturated, and 35% of that was polyunsaturated. The average daily consumption of gac fruit oil was estimated at 2 ml per person. The daily beta-carotene intake (from gac fruit oil) averaged approximately 5 mg per person. It was found that gac oil can be produced locally by village women using manual presses and locally available materials. The oil is a rich source of beta-carotene, vitamin E, and essential fatty acids. Although the beta-carotene concentration declines with time without a preservative or proper storage, it was still high after three months. The oil was readily accepted by the women and their children, and consumption of the oil increased the intake of beta-carotene and reduced the intake of lard.

Inhibitory effects of cucurbitane glycosides and other triterpenoids from the fruit of Momordica grosvenori on epstein-barr virus early antigen induced by tumor promoter 12-O-tetradecanoylphorbol-13-acetate

Two new triterpene benzoates, 5-dehydrokarounidiol dibenzoate (1) and karounidiol dibenzoate (2), and two new triterpene glycosides, 5alpha,6alpha-epoxymogroside IE(1) (8) and 11-oxomogroside A(1) (9), along with 15 known triterpenoids (one triterpene benzoate, 3; three triterpene mono-ols, 4-6; one triterpene aglycon, 7; and 10 triterpene glycosides, 10-19), were isolated from the ethanol extract of the fruit of Momordica grosvenori. The structures of 1, 2, 8, and 9 were determined on the basis of spectroscopic and chemical methods. Among the known triterpene glycosides, mogroside I E(1) (12) was a new naturally occurring compound. Eighteen triterpenoids (2-19) and 11-oxomogrol (20), a hydrolysis product of 9, were evaluated with respect to their inhibitory effects on the induction of Epstein-Barr virus early antigen (EBV-EA) by 12-O-tetradecanoylphorbol-13-acetate (TPA) in Raji cells, which is known to be a primary screening test for antitumor promoters. All of the compounds tested showed potent inhibitory effects on EBV-EA induction (70-100% inhibition at 1 x 10(3) mol ratio/TPA).

Carotenoid pigments in GAC fruit (Momordica cochinchinensis SPRENG)

The carotenoids in Gac fruit (Momordica Cochinchinensis spreng) were analysed by high-performance liquid chromatography (HPLC), and the concentrations of beta-carotene, lycopene, zeaxanthin and beta-cryptoxanthin were measured. Lycopene was found to be predominantly present in the Gac seed membrane at a concentration of up to 380 microg/g of seed membrane. The concentration of lycopene in the Gac seed membrane was about ten-fold higher than that in known lycopene-rich fruit and vegetables, indicating that Gac fruit could be a new and potentially valuable source of lycopene.

[Effects of Momordica saponins on endocrine function in senile mice]

AIM

To study the regulation effects of Momordica saponins on endocrine function in senile mice.

METHODS

15-month Kunming mice (female), were divided into senile control group (SC), experimental group 1 and 2 (E1 and E2). 10 4-month mice were as young control group (YC). All mice were fed with general foodstuff, SC and YC drank tap water, while two experimental groups drank tap water supplied to 100 mg/L and 200 mg/L Momordica saponins respectively. Serum was assayed after 5 weeks. At the same time, levels of estrogen receptor and its mRNA were assayed in cultured thymocyte from 12-month rat.

RESULTS

Serum ACTH and estradiol levels declined markedly in senile mice compared with young mice. ACTH levels increased in some extent in two experimental groups, while there had significant difference only in E2. Serum estradiol increased obviously, but there was no significant distinct between E1 and E2. The most important was that ER levels increased obviously, and there was no any change of ER mRNA levels in rat thymocyte cultured in medium contained different content of Momordica saponins.

CONCLUSION

Momordica saponins could improve endocrine function in senile mice by increasing ACTH level and expression of ER.

Alpha-glucosidase inhibitor from the seeds of balsam pear (Momordica charantia) and the fruit bodies of Grifola frondosa

Alpha-glucosidase inhibitory activities were found in aqueous methanol extracts of the seeds of Momordica charantia and the fruit bodies of Grifola frondosa. An active principle against the enzyme prepared from rat small intestine acetone powders was isolated and characterized. The structure of the isolated compound was identified as D-(+)-trehalose by FDMS, 1H-, 13C-NMR, and [alpha]D measurements. The inhibitory activity of trehalose was compared with 1-deoxynojirimycin. Trehalose showed 45% inhibitory activity at the concentration of 2 x 10(-3) m, but 1-deoxynojirimycin had 52% inhibitory activity at 1 x 10(-7) M.

A new multiflorane triterpenoid ester from Momordica cochinchinensis Spreng

A new triterpenoid ester 3,29-di-O-(p-methoxy)benzoylmultiflora-8-ene-3 alpha,29-diol-7-one from the seeds of Momordica cochinchinensis Spreng has been isolated. Its structure was elucidated by spectroscopic evidence and confirmed by X-ray crystallography.

Studies on chemical composition and utilization of the wild edible vegetable athalakkai (Momordica tuberosa)

A wild crop of athalakkai was identified, and the major nutrients of its fruits were assessed. South Indian recipes, poriyal, fry, pulikulambu, pickle, and vadagam, were prepared using athalakkai. Product acceptabilities were evaluated by a panel of 10 trained housewives using a 9-point hedonic scale. It was observed that athalakkai contains higher amounts of calcium, potassium, sodium, and vitamin C than bitter gourd (Momordica charantia L). It was also observed that athalakkai had a high crude fiber (6.42 g/100 g) content. The recipes prepared from athalakkai were highly acceptable. This research suggests the need to exploit this wild vegetable commercially through its increased use. However research should be conducted to identify the antinutritional factors and the effect of processing on these factors.

Shigellocidal properties of three Nigerian medicinal plants: Ocimum gratissimum, Terminalia avicennoides, and Momordica balsamina

The prevalence of multidrug-resistant shigellae is an important concern in the treatment of shigellosis in many developing countries, and other therapies, including herbal agents, may provide an important alternative to antimicrobial agents. In this study, three Nigerian medicinal plants: Ocimum gratissimum, Terminalia avicennoides, and Momordica balsamina were investigated for their activities against multidrug-resistant Shigella species isolated from patients with bacilliary dysentery in Lagos. Decoctions of O. gratissimum and concoctions of O. gratissimum and T. avicennoides at crude concentration of 3,000 micrograms/mL markedly inhibited the growth of all isolates tested. Zones of inhibition indicating susceptibilities of the organisms varied from 18.3 to 21.5 mm for Shigella dysenteriae, 15.3 to 16.3 mm for S. flexneri, 18.8 to 19.3 mm for S. sonnei, and 16.5 mm for S. boydii. Except S. flexneri, minimum inhibitory concentration and minimum bactericidal concentration revealed a higher shigellocidal property of O. gratissimum/T. avicennoides concoction than other extracts in S. dysenteriae (300-515.6 vs 337.5-1,312.5 micrograms/mL), S. sonnei (309.4-543.8 vs 403.1-1,312.5 micrograms/mL), and S. boydii (243.8-337.5 vs 253-1,312.5 micrograms/mL). O. gratissimum showed a greater shigellocidal effect against the S. flexneri isolates, while extracts of M. balsamina possessed low shigellocidal potential. The results suggest that aqueous extracts of O. gratissimum and T. avicennoides as decoctions and concoctions could be useful in the treatment of shigellosis and should be clinically evaluated specially in Nigerian region.

Rapid analysis of momordicoside A in bitter melon by high performance liquid chromatography following solid phase extraction

A rapid, simple and accurate method for the determination of momordicoside A has been established using solid phase extraction (SPE) followed by high performance liquid chromatography (HPLC). Sample was processed by SPE on a Carb cartridge (3 mL/250 mg), and was then determined by HPLC on a C18 column (4.6 mm i.d. x 250 mm, 5 microns) with V(acetonitrile):V(methanol):V(50 mmol/L potassium dihydrogen phosphate buffer) = 25:20:60 as mobile phase (0.8 mL/min) and UV detection at 208 nm. The calibration curves were linear from 10 mg/L to 1,000 mg/L (r2 = 0.9992). The analytical method was shown to be highly reproducible, giving all of the relative standard deviations and relative mean errors less than 10% for both intra-day and inter-day determinations. The absolute recoveries were greater than 90%.

[Triterpenes and steroidal compounds from Momordica dioica]

Three triterpenes and two steroidal compounds were isolated from the dry root of Momordica dioica. Their structures were elucidated by spectral analyses (MS, IR, 1HNMR, 13CNMR and DEPT) and chemical methods. These compounds are alpha-spinasterol octadecanonate(I), alpha-spinasterol-3-O-beta-D-glucopyranoside(II), 3-O-beta-D-glucuronopyranosyl gypsogenin(III), 3-O-beta-D-glucopyranosyl gypsogenin(IV) and 3-O-beta-D-glucopyranosyl hederagenin(V). Constituent III is a new compound. The CHCl3 extract of Momordica dioica roots and five isolated constituents showed anticancer activity in pharmacologic testing on cancer cell(L1210). The growth inhibitory index(%) of compound II was shown to be 50%, at the dose of 4 micrograms.ml-1.