Megastigmane, aliphatic alcohol and benzoxazinoid glycosides from Acanthus ebracteatus.

From the aerial part of Acanthus ebracteatus, a megastigmane glycoside (ebracteatoside A), three aliphatic alcohol glycosides (ebracteatosides B-D), as well as 7-chloro-(2R)-2-O-beta-D-glucopyranosyl-4-hydroxy-2H-1,4-benzoxazin-3(4H)-one (7-Cl-DIBOA-Glc) were isolated together with 22 known compounds. Structural elucidations were based on analyses of spectroscopic data.

Acetylated triterpene saponins from the Thai medicinal plant, Sapindus emarginatus.

From the pericarps of Sapindus emarginatus (Sapindaceae), three new acetylated triterpene saponins were isolated together with hederagenin and five known triterpene saponins, as well as one known sweet acyclic sesquiterpene glycoside, mukurozioside IIb. The structures of new compounds were elucidated as hederagenin 3-O-(2-O-acetyl-beta-D-xylopyranosyl)-(1-->3)-alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranoside, 23-O-acetyl-hederagenin 3-O-(4-O-acetyl-beta-D-xylopyranosyl)-(1-->3)-alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranoside and oleanolic acid 3-O-(4-O-acetyl-beta-D-xylopyranosyl)-(1-->3)-alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranoside by chemical and spectroscopic data.

Lignan and phenylpropanoid glycosides from Fernandoa adenophylla.

From the leaves and branches of Fernandoa adenophylla, a lignan glycoside (fernandoside) and a phenylpropanoid glycoside (2"-O-beta-apiosylverbascoside) were isolated together with 12 known compounds. The structural elucidations were based on analyses of physical and spectroscopic data.

Acylated flavonoid glycosides from Bassia muricata.

From the arial parts of Bassia muricata, two acylated flavonoid glycosides quercetin-3-O-(6"-caffeoyl)-sophoroside and quercetin-3-O-(6"-feruloyl)-sophoroside have been isolated together with two known flavonoid glycosides quercetin-3-O-sophoroside and quercetin-3,7-O-beta-diglucopyranoside, as well as four known triterpenoidal saponins, oleanolic acid-3-O-beta-glucopyranoside, chikusetsusaponin IVa, chikusetsusaponin IVa methyl ester and oleanolic acid-3,28-beta-diglucopyranoside. The structures of the isolated compounds were verified by means of MS and NMR spectral analyses.

Effects of olive, corn, sesame or peanut oil on the body weights and reproductive organ weights of immature male and female rats.

Olive, corn, sesame or peanut oil which have been used as vehicles in the immature rat uterotrophic assay or Hershberger assay, for detection of endocrine disrupting effects of environmental chemicals, was administered to ten immature female rats by subcutaneous injection from postnatal day (PND) 21 for 3 or 7 days, and each oil was also administered to ten male rats from PND 21 for 7 and 10 days. The body weights, and the weights of sex and sex accessory organs in female and male rats were measured. There were no significant differences in body weights of female rats between each oil group and the control group, while the body weight of male rats in the group given peanut or olive oil was significantly increased from 8 or 9 days after administration. There were no changes in the sex and sex accessory organ weights of female or male rats related to the endocrine disrupters. The results of the body weights and organ weights demonstrate that each oil is a suitable vehicle for the immature rat uterotrophic assay. However, each oil is suggested to be unsuitable for the Hershberger assay, because the analysis of changes of sex accessory organ weights in this assay might be confused by the increased body weights.

Sweet pregnane glycosides from Telosma procumbens.

An intensely sweet polyoxypregnane glycoside, telosmoside A15 (15), was isolated from an Asian Asclepiadaceae plant, Telosma procumbens, collected in Vietnam. This is the first time a sweet pregnane glycoside has been found, and its sweetness intensity is 1000 times greater than that of sucrose. From the same plant, 17 other new glycosides were isolated, having the same aglycone; they are named telosmosides A1-A14 (1-14) and A16-A18 (16-18). Some of these glycosides are also sweet, but others are tasteless or bitter. Chemical structures of the 18 glycosides were determined, and the structure-taste relationship was discussed.

Lignan glucosides from Acanthus ilicifolius.

From the aerial part of Acanthus ilicifolius, two lignan glucosides, (+)-lyoniresinol 3a-[2-(3,5-dimethoxy-4-hydroxy)-benzoyl]-O-beta-glucopyranoside, and dihydroxymethyl-bis(3,5-dimethoxy-4-hydroxyphenyl) tetrahydrofuran-9(or 9')-O-beta-glucopyranoside have been isolated, together with eight known compounds. The structural elucidations were based on the analyses of physical and spectroscopic data.

Canthin-6-one and beta-carboline alkaloids from Eurycoma harmandiana.

Two alkaloids, canthin-6-one 9-O-beta-glucopyranoside and 7-hydroxy-beta-carboline 1-propionic acid, were isolated from the roots of Eurcoma harmandiana together with the five known canthin-6-one alkaloids, 9-hydroxycanthin-6-one, 9-methoxycanthin-6-one, 9,10-dimethoxycanthin-6-one, canthin-6-one and canthin-6-one N-oxide, and the two known beta-carboline alkaloids, beta-carboline 1-propionic acid and 7-methoxy-beta-carboline 1-propionic acid. Their structures were based on analyses of spectroscopic data.

Major metabolites of ginseng sapogenins formed by rat liver microsomes.

Incubation of ginseng sapogenins with microsomes from rat liver resulted in formation of their 20,24-epoxides as major metabolites. Identification of the metabolites was performed by HPLC, FAB-MS and EI-MS.

Triterpenoidal saponins from Cornulaca monacantha.

From the aerial parts of Cornulaca monacantha, three new triterpenoidal saponins have been isolated and their genuine structures were identified as 3-O-[beta-xylopyranosyl-(1-->3)-beta- glucuronopyranosyl]-30-methylphytolaccagenate (2), 3-O-[beta-xylopyranosyl- (1-->3)-beta-glucuronopyranosyl]-30-methylphytolaccagenate 28-O-beta-gluco-pyranoside (3) and 3-O-[beta-xylopyranosyl-(1-->3)-beta- glucurono-pyranosyl]-30-methylserjanate 28-O-beta glucopyranoside (4) together with nine known saponins of oleanolic acid (5-9), hederagenin (1, 10, 11) and 30-methyl phytolaccagenate (12).

Suppressive effects of vietnamese ginseng saponin and its major component majonoside-R2 on psychological stress-induced enhancement of lipid peroxidation in the mouse brain.

We investigated the in vivo effects of Vietnamese ginseng saponin (VG saponin) and its major component majonoside-R2 (MR2) on psychological stress-induced enhancement of lipid peroxidation in the mouse brain. Psychological stress exposure using a communication box system for 4 h significantly increased the content of thiobarbituric acid reactive substance (TBARS), an index of lipid peroxidation activity, in the brain. Pretreatment with VG saponin (15-25 mg/kg, PO) and MR2 (1-10 mg/kg, IP) significantly attenuated the psychological stress-induced increase in TBARS content in the brain. The aglycone of MR2 (MR2-aglycone: 1.2 mg/kg, IP), at the equivalent dose of MR2 (i.e., 3 mg/kg, IP), also produced the suppressive effect on the increase in the TBARS content. The in vivo suppressive effect of MR2 was dose dependently attenuated by flumazenil (3 and 10 mg/kg, IP), a benzodiazepine receptor antagonist, and pregnenolone sulfate (10 mg/kg, IP), a neurosteroidal negative allosteric modulator of GABA(A) receptors. These findings suggest that VG saponin and its major component MR2 have preventive effects on the psychological stress-induced brain cell membrane damage, and that the effect of MR2 is partly due to enhancement of GABA(A)-ergic systems in the brain.

Monoterpene and pregnane glucosides from Solenostemma argel.

From the aerial parts of Solenostemma argel, two monoterpene glucosides have been isolated and identified as 6,7-dihydroxy-dihydrolinalool 3-O-beta-glucopyranoside and 6,7-dihydroxy-dihydrolinalool 7-O-beta-glucopyranoside. A pregnane glucoside was also isolated and assigned as pregn-5-ene-3,14-beta-dihydroxy-7,20-dione 3-O-beta-glucopyranoside together with the known compounds benzyl alcohol O-beta-apiofuranosyl-(1-->6)-beta-glucopyranoside, 2-phenylethyl O-alpha-arabinopyranosyl-(1-->6)-beta-glucopyranoside, astragalin and kaempferol-3-O-alpha-rhamnopyranosyl-(1-->2)-beta-glucopyranoside.

Chalcanol glucosides from seeds of Trifolium alexandrinum.

Three new chalcanol glucosides have been isolated from the seeds of Trifolium alexandrinum, of which the first two are alpha'-chalcanol-alpha, beta-epoxides and the third one is an alpha, beta-dihydroxy-alpha'-chalcanol. The structures of the isolated compounds were verified by means of MS and 2D NMR spectral analyses.

Bioactive saponins in vietnamese ginseng, panax vietnamensis.

Vietnamese ginseng, Panax vietnamensis was recently found in central Vietnam, and regarded as a new botanical species. It was used in traditional folk medicine in hill tribes for the purpose of anti-fatigue and life saving. From the rhizome and root of this plant, 37 saponins including 14 new compounds were isolated. Some of them were common to other Panax spp., but the general yields in this species were very high. Among them, an ocotillol-type saponin majonoside-R2 (MR2) was remarkable in its yield (5.3%). Structural features of new saponins were briefly introduced. The biological effects of these saponins were studied in two ways, anti-stress effect and anti-tumor promoting effect; both activities were based upon the traditional usage of this crude drug. In psychologically stressed mice, the saponin fraction of Vietnamese ginseng significantly reduced stress-related disorders (reducing sleeping time, formation of gastric lesions) and MR2 was responsible for this effect. A possible mechanism for this effect was proposed. MR2 exhibited a significant inhibitory effect on Epstein-Barr virus early antigen (EBV-EA) induced by the tumor promoter phorbol acetate. MR2 also showed potent anti-tumor-promoting activity on mouse skin and hepatic tumors.

The correlation between feed-intake cycle and nutritional zinc-deficient status in rats.

The characteristic cyclic variation in feed intake of rats fed a Zn-deficient diet (Mills et al, Am J Clin Nutr 22: 1240-1249 (1969)) followed a Cosinor curve, as determined by computer analysis (Tamaki et al, Br J Nutr 73: 711-722 (1995)). The values of amplitude for the feed-intake cycle had a positive correlation to their own day-to-day variations and to the correlation value of their own simulated cycles (r2 = 0.764, df = 50, p < 0.001 and r2 = 0.682, df = 50, p < 0.001, respectively). The cyclic variation in feed intake was accompanied by a cyclic variation in body-weight change in rats fed the Zn-deficient diet, and cyclic variation in body-weight change occurred similarly in pair-fed control rats. There were no differences in the mesors of body-weight change cycles of Zn-deficient rats and pair-fed control rats (Zn-deficient rats: 2.5 +/- 1.0 g/d, pair-fed rats: 2.8 +/- 1.0 g/d, mean +/- SD, df = 18, t = -0.674, ND). Rats fed the Zn-deficient diet were given different amounts of Zn supplementation by daily subcutaneous injection. The amplitude of the feed-intake cycle was decreased with increasing Zn supplementation (r2 = 0.919, df = 5, p < 0.001). The concentration of Zn for the appearance of the feed-intake cycle was estimated to be 71.6 +/- 6.6 micrograms/d per rat. The Zn level in the serum showed a significant decrease in the Zn-deficient diet groups, but the supplement of Zn did not vary in the Zn-deficient rats injected with up to 47.3 micrograms/d per rat. From these results, an analysis of the feed-intake cycle allowed us to estimate the quantitative Zn-deficient status of rats.

[Transanal endoscopic microsurgery (TEM)].

Minimally invasive surgery is mandatory for rectal tumors to reduce surgical complications and to improve the quality of life. The conventional transanal procedure is one from of minimally invasive surgery for rectal tumors, but it is still often difficult to reach the middle and upper thirds of the rectum due to anatomical characteristics. Transanal endoscopic microsurgery (TEM) is a technique that allows radical resection of rectal tumors in the distal as well as proximal third of the rectum. Performing radical surgery using this technique requires preoperative estimation of tumor extension both histologically and by X-ray images. It should allow provide safe and radical excision of rectal tumors. In our department, patients with rectal tumors are evaluated for risk factors using barium enema, endoscopic ultrasound, punch biopsy, etc. Fifty patients (rectal cancer, 34: cartinoid, 4: adenoma, 12) have undergone radical TEM. The operation was converted to open surgery in 2 cases because of rectal perforation. Radical open surgery was performed after TEM in 1 patient since cancer invasion was revealed by postoperatively upon histological examination. We conclude that TEM is a useful technique for radical resection of rectal tumors and is associated with a low rate of postoperative complications and a high surgical success rate.

Cancer chemopreventive activity of majonoside-R2 from Vietnamese ginseng, Panax vietnamensis.

In the course of our continuing search for novel cancer chemopreventive agents from natural sources, several kinds of Panax plants were screened. Consequently, the ocotillol-type saponin, majonoside-R2 (MR2), was obtained from the rhizome and root of Panax vietnamensis (Vietnamese ginseng) as an active constituent. MR2 exhibited potent anti-tumor-promoting activity on two-stage carcinogenesis test of mouse hepatic tumor using N-nitrosodiethylamine (DEN) as an initiator and phenobarbital (PB) as a promoter. Further, MR2 exhibited the remarkable inhibitory effect on two-stage carcinogenesis test of mouse skin induced by nitric oxide (NO) donor/12-O-tetradecanoylphorbol-13-acetate (TPA) or peroxynitrite/TPA.

In vitro antioxidant activity of Vietnamese ginseng saponin and its components.

To elucidate the antioxidant action of Vietnamese ginseng saponin against free radial-mediated cellular damage, we examined the effect of Vietnamese ginseng saponin on lipid peroxidation in the mouse brain, liver, and liver microsomes by using two in vitro free radical generating systems (iron ferrous+ascorbic acid and iron ferrous+hydrogen peroxide). Free radical-mediated lipid peroxidation was determined by measuring the endogenous and stimulated accumulation of thiobarbituric acid reactive substance (TBA-RS). Vietnamese ginseng saponin (0.05-0.5 mg/ml), as well as vitamin E, significantly inhibited the formation of TBA-RS in tissue homogenates. Panax ginseng saponin, at the same concentration range as Vietnamese ginseng saponin, also had inhibitory action on free radical-mediated lipid peroxidation. However, majonoside-R2, ginsenoside-Rg1 and ginsenoside-Rb1, the main saponin components of Vietnamese ginseng saponin fraction, had no effect on lipid peroxidation. These results suggest that Vietnamese ginseng exerts a protective action against free radical-induced tissue injury and that this effect is attributable to minor components rather than the main saponin components tested.

[Inhibitory effects of natural medicines on the enzymes related to the skin].

In this paper, we investigated the inhibitory effects of water extracts from sixty-six natural medicines on the enzymes related to the skin, which were tyrosinase, hyaluronidase and collagenase. To clarify the inhibitory components in water extracts, tannin quantity and the inhibitory activity of the water extracts after removal of phenolic compounds using polyclar AT, were measured. Twelve kinds of natural medicines were found to have tyrosinase inhibitory activity. Six of them showed that tannin, which contains sufficient amounts in extracts, might be major inhibitory compounds due to a significant decrease of inhibition by these samples after removal of phenolic compounds. The inhibitory compound of Aurantii fructus immaturus was thought phenolic compounds except tannin. The inhibitory compounds may include Armeniacae semen, Perillae folium and Persicae semen besides a phenolic compound. Twenty-seven species among the natural medicines studied showed inhibitory activity on hyaluronidase. Phenolic compounds in these extracts except Artemisiae argyi folium, could not be candidates for hyaluronidase inhibitors. Seven kinds of the natural medicines have inhibitory activity on collagenase. It was estimated that these inhibitory compounds were phenolic compounds. These results are to be expected for finding novel compounds for skin disease or skin-care cosmetics.

Anti-HIV-1 activity of herbs in Labiatae.

The anti-HIV-1 activity of aromatic herbs in Labiatae was evaluated in vitro. Forty five extract from among 51 samples obtained from 46 herb species showed significant inhibitory effects against HIV-1 induced cytopathogenicity in MT-4 cells. In particular, the aqueous extracts of Melissa officinalis, a family of Mentha x piperita "grapefruit mint," Mentha x piperita var. crispa, Ocimum basilicum cv "cinnamon," Perilla frutescens var. crispa f. viridis, Prunella vulgaris subsp. asiatica and Satureja montana showed potent anti-HIV-1 activity (with an ED of 16 microg/ml). The active components in the extract samples were found to be water-soluble polar substances, not nonpolar compounds such as essential oils. In addition, these aqueous extracts inhibited giant cell formation in co-culture of Molt-4 cells with and without HIV-1 infection and showed inhibitory activity against HIV-1 reverse transcriptase.