Biological activity of a fruit vegetable, "Anastasia green", a species of sweet pepper.

Russian green sweet pepper (Anastasia Green) was successively extracted with hexane, acetone, methanol and 70% methanol and the extracts were further separated into a total of twenty fractions by silica gel or ODS column chromatographies. The biological activities of these extracts and fractions were compared. The extracts and fractions showed higher cytotoxic activity against two human oral tumor cell lines than against normal human gingival fibroblasts, suggesting their tumor-specific action. Several fractions [H3, H4, A4] reversed the multidrug resistant gene (MDR1) against L5178 mouse T-cell lymphoma more effectively than (+/-) verapamil (positive control). All extracts and fractions showed no anti-human immunodeficiency virus (HIV) nor anti-Helicobacter pylori activity. These data suggest the medicinal importance of an Anastasia Green extract.

Relationship between cytotoxic activity and radical intensity of isoflavones from Sophora species.

Among 11 isoflavones tested, genistein [YS13] produced higher cytotoxic activity against human oral tumor cell lines (HSC-2, HSG) than against normal cells (human gingival fibroblast, HGF), suggesting its tumor-specific action. Electron spin resonance (ESR) spectroscopy showed that YS13 did not produce radical, nor scavenged O2*- generated by hypoxanthine-xanthine oxidase reaction system, suggesting that radical-mediated oxidation mechanism is not be involved in the YS13-induced cytotoxicity. Addition of one prenyl group produced YS18 and YS19 with higher anti-Helicobacter pylori activity. Addition of two prenyl groups produced YS21 with the highest cytotoxic activity but lower tumor-specificity. Since YS21 produced the highest amount of radical and most efficiently scavenged O2*-, this compound may induce cytotoxicity by radical-mediated oxidation mechanism. All isoflavones failed to induce anti-human immunodeficiency virus (HIV) activity. These data suggest the medicinal efficacy of isoflavones.

Inhibitory effects of licoisoflavones A and B and sophoraisoflavone A of Sophra mooracroftiana Beth ex Baker on copper-ion-induced protein oxidative modification of mice brain homogenate, in vitro.

We present the results of an in vitro investigation of the inhibitory effects of licoisoflavones A and B and sophoraisoflavone A isolated from Sophra mooracroftiana BETH ex BAKER on copper-induced protein oxidative modification of mice brain homogenate in vitro. Although inhibitory effect of sophoraisoflavone A was stronger than those of licoisoflavones A and B, genistein as a related isoflavone, and mannitol as a hydroxy radical scavenger, inhibitory effects of licoisoflavones A and B were weaker than those of genistein and mannitol. These results demonstrated that the difference of inhibitory effects are dependent on the relation between chemical structures of these isoflavones, such as hydroxy group or benzopyran, and oxidative stress.

Inhibitory effects of echinoisoflavanone and sophoraisoflavanone D in Sophora chrysophylla SEEM on lipid peroxidation of mice brain homogenate by interaction of ferrous ion and hydrogen peroxide, in vitro.

We present the results of an in vitro investigation of the inhibitory effects of echinoisoflavanone and sophoraisoflavanone D isolated from Sophora chrysophylla SEEM on lipid peroxidation of mice brain homogenate by interaction of ferrous ion and hydrogen peroxide, in vitro. They inhibited lipid peroxidation. The order of inhibitory effects of these isoflavanones and mannitol as a hydroxy radical scavenger was echinoisoflavanone > mannitol > sophoraisoflavanone D. The results suggest that some isoflavanones may be of use in cases where oxidative stress is present.

Stilbenoids in lianas of Gnetum parvifolium.

Five new stilbene dimers were isolated from the lianas of Gnetum parvifolium in addition to known stilbenoids. The structures of the compounds were established on the basis of spectroscopic evidence, including long-range coupling and nuclear Overhauser effect experiments, in NMR spectrum. Among the isolates, 2b-hydroxyampelopsin F showed potent inhibitory activity in the Maillard reaction.

Biological activity of kiwifruit peel extracts.

Various bioactive substances in kiwifruit extracts were fractionated by organic solvent extractions, followed by silica gel and ODS chromatographies. Both cytotoxic activity and multi-drug resistance reversal activity were found in the less polar fractions. Cytotoxic activity was not always parallel the radical intensity. Antibacterial activity was distributed into various fractions and all fractions were inactive against Candida albicans and H. pylori. Only 70% methanol extracts showed anti-human immunodeficiency virus activity, and produced a broad ESR signal under alkaline conditions, in a fashion similar to lignin. These fractions also effectively scavenged O(2)(-) produced by the xanthine-xanthine oxidase reaction, suggesting a bimodal (pro-oxidant and antioxidant) action. These data suggest a medicinal efficacy of kiwifruit peel extracts.

Comparison of antioxidative and chelating effects of daidzein and daidzin on protein oxidative modification by copper in vitro.

Daidzein and its glycoside daidzin are isoflavones. Their antioxidative effects were compared in vitro. Although both compounds inhibited protein oxidative modification by copper, the inhibitory effect of daidzein was stronger than that of daidzin. Because daidzein showed a greater affinity for Cu2+, the antioxidant effect of these isoflavones may be dependent on their respective copper-chelating abilities.

In vitro biological activity of prenylflavanones.

The biological activity of ten prenylflavanones purified from Sophora tomentosa L., and Sophora moorcroftiana Benth. ex Baker (Leguminosae) was investigated. The flavanones with prenyl-, lavandulyl- or geranyl groups on A ring, and two bioactive flavonostilbenes on ring B and stilbene (resveratrol) showed tumor-specific cytotoxic activity, antimicrobial activity, and anti-HIV activity, radical generation, and O2- scavenging activity. There was a positive relationship between radical generation and O2- scavenging activity in these prenylflavanones. These data suggest the medicinal significance of prenylflavanones.

Monitoring of MRP-like activity in human erythrocytes: inhibitory effect of isoflavones.

A method to fluorometrically monitor efflux of 2',7'-bis-(carboxypropyl)-5(6)-carboxyfluorescein (BCPCF) from human erythrocytes was developed. Genistein, daidzein, sophoraisoflavone A, and licoisoflavone A induced 50% inhibition (IC(50)) of BCPCF efflux at 15-70 microM. The IC(50) value of the most efficient isoflavone, licoisoflavone A (15-25 microM), was comparable to that of indomethacin (approximately 10 microM) and markedly lower than for probenecid (100-200 microM), both known MRP1 inhibitors. Our results indicate that the human erythrocyte is a useful cell model in screening potential MRP inhibitors, that BCPCF is a good substrate for MRP, and that some isoflavones at low concentrations inhibit MRP-mediated efflux.

Antimicrobial activity of prenylflavanones.

Among two flavanones [YS01, YS02] and eight prenylflavanones [YS03-YS10], preliminary screening with fifteen test bacterial strains showed that YS06 was the most active agent. YS06 exhibited highly significant antimicrobial action when tested against 228 bacterial strains comprising two Gram-positive and six Gram-negative genera. The in vitro susceptibility test was carried out by determining the minimum inhibitory concentration (MIC) of YS06 by agar dilution technique. Twenty-two out of fifty strains of Staphylococcus aureus were inhibited at 25 to 50 micrograms/mL of the agent. YS06 also inhibited strains of Salmonella, Shigella and a few strains of Escherichia coli strains were also highly sensitive to YS06, while Kleibsiella spp. and Pseudomonas aeruginosa were much less sensitive. In in vivo study, YS06 offered significant protection (p < 0.001 according to chi-square test) to Swiss albino mice (challenged with 50 minimum lethal dose (MLD, virulent bacterium) at concentrations of 160 and 80 micrograms/mouse.

Antioxidative activity of Allium victorialis L. extracts.

Allium victorialis L. (Liliaceae, "Hon-Gyoujya Nin-Niku" in Japanese) was successively extracted with hexane, acetone, methanol and 70% methanol and the extracts were further separated into a total of twenty-five fractions by silica gel and ODS column chromatographies. The biological activities of these four extracts and 25 column fractions were compared. The cytotoxic activity of all extracts and fractions against two oral tumor cell lines was significantly higher than that against normal human gingival fibroblasts, suggesting their tumor-specific action. Three methanol column fractions [M2, M3, M6] and a 70% methanol column fraction [70M6] most effectively reversed the multidrug resistance (MDR) against L5178 mouse T cell lymphoma. The electron spin resonance (ESR) spectroscopy showed that methanol column fractions and 70% methanol extracts produced the highest amount of radical(s) and most efficiently scavenging O2*-, generated by the hypoxanthine-xanthine reaction system, suggesting that the same substances in these fractions display both prooxidant and antioxidant properties. They showed no anti-human immunodeficiency virus (HIV) or anti-Helicobacterpylori activity. These data suggest the medicinal efficacy of Allium victorialis extract.

Inhibitory effects of astragali radix, crude drug in Oriental medicines on lipid peroxidation and protein oxidative modification of mouse brain homogenate by copper.

Astragali Radix, the root of Astragalus membranaceus Bunge, is a crude drug used widely in Oriental medicines. It is a major component of Ougi-Keishi-gomotsu-to, a traditional herbal medicine, used for neurop patients with abnormal sensations and neuropathic pain of the legs. It was shown to have inhibitory effects on lipid peroxidation and protein oxidative modification by copper. The effects were similar to and stronger than those of mannitol and superoxide dismutase as free radical scavengers. These results demonstrated that Astragali Radix has inhibitory effects on oxidative stress induced by metal.

Selective cytotoxic activity of grape peel and seed extracts against oral tumor cell lines.

Grape seed extracts were more cytotoxic than grape peel extracts. Methanol and 70% methanol extracts of grape seed selectively killed two human oral tumor cell lines, more efficiently than human gingival fibroblasts. ESR spectroscopy revealed that these extracts produced radicals under alkaline conditions and enhanced the radical intensity of sodium ascorbate at higher concentrations. On the other hand, lower concentration of these extracts slightly reduced the radical intensity of sodium ascorbate, and scavenged superoxide anion, generated by hypoxanthine and xanthine oxidase reaction. These properties of grape seed extracts suggest their possible application for cancer prevention.

Biological activity of feijoa peel extracts.

Fractionated extracts of Feijoa peels were studied for cytotoxic activity, anti-human immunodeficiency virus (HIV) activity and antibacterial activity. Two most cytotoxic fractions A3 of acetone extract and M2 of methanol extract had potent inhibitory activity against Gram-positive and Gram-negative bacteria as well as fungi tested. Fraction A4 of acetone extract showed multidrug resistance (MDR)-reversal activity comparable with that of verapamil (positive control). These results indicate the therapeutic value of Feijoa peel extracts as potential antimicrobial and MDR-modulating agents.

Inhibitory effects of sophoraflavanones B and H in Sophora mooracroftiana Beth ex Baker on copper-ion-induced protein oxidative modification of mice brain homogenate in vitro.

We present the results of an in vitro investigation of the inhibitory effects of sophoraflavanones B and H isolated from Sophora mooracroftiana Beth ex Baker on copper-induced protein oxidative modification. They inhibited copper-induced protein oxidative modification. Their effects were stronger than those of naringenin as a related flavanone, and of mannitol as a hydroxyl radical scavenger. The results suggest that these natural products may be of use in cases where oxidative stress is present.

Relationship between radical intensity and biological activity of cacao husk extracts.

The relationship between radical intensity and biological activity of cacao husk extracts was investigated. Electron spin resonance (ESR) spectroscopy demonstrated that the radical intensity of hexane, acetone, methanol and 70% methanol extracts increased with water-solubility. Several fractions of these husk extracts, separated by different column chromatographies, significantly inhibited the cytopathic effect of human immunodeficiency virus (HIV) infection in parallel with their radical intensity. However, their cytotoxic activity against human leukemic and carcinoma cell lines is not always correlated with their radical intensity. Water-soluble and lipophilic compounds might induce cytotoxic activity by different mechanisms.

Inhibitory effects of isoflavones on lipid peroxidation by reactive oxygen species.

Possible inhibitory effects were investigated for four isoflavones, biochanin A, daidzein, formononetin and genistein on lipid peroxidation by reactive oxygen species. Biochanin A, formononetin and genistein inhibited lecithin peroxidation which was induced by hydroxy radical generation, by interaction of haemoglobin and hydrogen peroxide. Daidzein and formononetin inhibited lecithin peroxidation which was induced by superoxide anion generation by xanthine-xanthine oxidase. These results demonstrated that the differences in antioxidant activities of isoflavones are dependent on the relation between their chemical structures and reactive oxygen species.

Inhibitory effects of Astragali Radix, a crude drug in Oriental medicines, on lipid peroxidation and protein oxidative modification by copper.

Effects of Astragali Radix, the root of Astragalus membrauaceus Bunge, were investigated on oxidative stress such as lipid peroxidation and protein oxidative modification by copper. The results showed that these effects are similar to those of mannitol and superoxide dismutase as a free radical scavenger. It was demonstrated that Astragali Radix have inhibitory effects on oxidative stress induced by copper.

[Studies on antiulcer agents. III. Synthesis and antiulcer activity of phenylpropanol derivatives].

It was found that (+/-)ethyl 2-[2-(3-hydroxypropyl)-4-oxocyclohexylidene]-propionate (1), (+/-)ethyl 2-[2-(3-hydroxypropyl)-4,5-dimethoxyphenyl]propionate (2) and (+/-)3-[2-(3-hydroxypropyl)-4,5-dimethoxyphenyl]-2-butanone (3) had excellent antiulcer activities. In order to study structure-activity relationships, (+/-)2-[(3-hydroxypropyl)phenyl]cyclopentanone derivatives (4, 5) and (+/-)2-[(3-hydroxypropyl)phenyl]cyclopentanol derivatives (6, 7) were synthesized and tested for antiulcer activities. As a result, (+/-)2-[2-(3-hydroxypropyl)-4-methoxy-5-(2- piperidinoethoxy)phenyl]cyclopentanone (5k) exhibited potent antiulcer activities.

[Studies on antiulcer agents. IV. Synthesis and antiulcer activity of phenylpropanol derivatives].

It was found that (+/-)ethyl 2-[2-(3-hydroxypropyl)-4-oxocyclohexylidene-propionate (1), (+/-)ethyl 2-[2-(3-hydroxypropyl)-4,5-dimethoxyphenyl]propionate (2), (+/-)3-[2-(3-hydroxypropyl)-4,5-dimethoxyphenyl]-2-butanone (3) and (+/-)2-[2-(3-hydroxypropyl)-4-methoxy-5-(2- piperidinoethoxy)phenyl]cyclopentanone (4) had potent antiulcer activities. In order to study structure-activity relationships, (+/-)3-[(3-hydroxypropyl)phenoxy]-2-butanone derivatives (5, 6) were synthesized and tested for antiulcer activities. Among them, (+/-)3-[2-(3-hydroxypropyl)-4-methoxy-5-[3-(4- methylpiperidino)propoxy]phenoxy]-2-butanone.3/2 oxalate (6k) was selected as a preferred antiulcer agent.