Showing papers in "Journal of Natural Medicines in 2008"

Plant-derived natural product research aimed at new drug discovery.

Abstract: Many important bioactive compounds have been discovered from natural sources using bioactivity-directed fractionation and isolation (BDFl) [Balunas MJ, Kinghorn AD (2005) Drug discovery from medicinal plants. Life Sci 78:431–441]. Continuing discovery has also been facilitated by the recent development of new bioassay methods. These bioactive compounds are mostly plant secondary metabolites, and many naturally occurring pure compounds have become medicines, dietary supplements, and other useful commercial products. Active lead compounds can also be further modified to enhance the biological profiles and developed as clinical trial candidates. In this review, the authors will summarize research on many different useful compounds isolated or developed from plants with emphasis placed on those recently discovered by the authors’ laboratories as antitumor and anti-HIV clinical trial candidates.

Antioxidant constituents in the dayflower (Commelina communis L.) and their α-glucosidase-inhibitory activity

Abstract: The dayflower, Commelina communis L., contains 1-deoxynojirimycin (DNJ) and (2R,3R,4R,5R)2,5-bis(hydroxymethyl)-3,4-dihydroxypyrrolidine (DMDP), potent α-glucosidase inhibitors. The extracts and powder of this herb are important food materials for prophylaxis against type 2 diabetes. Eleven flavonoid glycosides as antioxidants, isoquercitrin, isorhamnetin-3-O-rutinoside, isorhamnetin-3-O-β-d-glucoside, glucoluteolin, chrysoriol-7-O-β-d-glucoside, orientin, vitexin, isoorientin, isovitexin, swertisin, and flavocommelin, were identified from the aerial parts of C. communis. Their antioxidant activities were measured using in vitro assays employing the 1,1-diphenyl-2-picrylhydrazyl radical- and superoxide radical-scavenging assays. The results showed that glucoluteolin, orientin, isoorientin, and isoquercitrin are the predominant antioxidants in this herb. Moreover, isoquercitrin, isorhamnetine-3-O-rutinoside, vitexin, and swertisin inhibited the activity of α-glucosidase from rat intestine.

Antibacterial activity of some medicinal plant extracts.

Abstract: Antibacterial activity of hot aqueous and methanolic extracts prepared from six plants (Terminallia chebula, Terminallia bellerica, Phyllanthus emblica, Punica granatum, Lawsonia alba and Mikania micrantha) used in traditional folk medicines of India were screened against five pathogenic bacteria (Staphylococcus aureus MTCC 2940, Bacillus subtilis MTCC 441, Escherichia coli MTCC 739, Proteus vulgaris MTCC 426 and Enterobacter aerogenes MTCC 111). The highest antibacterial potentiality was exhibited by the methanolic leaf extract of T. chebula, followed by the aqueous fruit extract of T. bellerica. The leaf extract of T. chebula can be considered to be as equally potent as the most effective antibiotics, such as ciprofloxacin, gentamycin, kanamycin, ofloxacin and cephalexin. A sensitivity test performed with commonly used sensitivity test disks resulted in the appearance of multiple drug resistance phenotypes of the bacteria tested. A comparision of data in the inhibition zones of pathogenic bacteria showed that gentamycin, ofloxacin, kanamycin and tobramycin were effective against all of the bacterial strains tested.

Antihyperglycemic and antioxidative potential of Matricaria chamomilla L. in streptozotocin-induced diabetic rats

Abstract: Plants with antidiabetic activities provide important sources for the development of new drugs in the treatment of diabetes mellitus. In the present study, we investigated possible antihyperglycemic and antioxidative activities of the aerial part of the Matricaria chamomilla L. ethanolic extract (MCE) in streptozotocin (STZ; 70 mg/kg, i.p.)-induced diabetic rats. The following groups were assigned; sham (did not receive any substance), STZ + distilled water (control), STZ + 5 mg/kg glibenclamide, STZ + 20 mg/kg MCE, STZ + 50 mg/kg MCE, STZ + 100 mg/kg MCE. Diabetic rats were treated for 14 days by gavage. Postprandial blood glucose levels, malondialdehyde, reduced glutathione (GSH), nitrate, nitrite, ascorbic acid, retinol, β-carotene, superoxide dismutase, and catalase levels were measured, and immunohistochemical studies were performed in all of the groups. The obtained data showed that STZ resulted in oxidative stress and affected the antioxidant status. Treatment with different doses of MCE significantly reduced postprandial hyperglycemia and oxidative stress, and augmented the antioxidant system. In histological investigations, MCE treatment protected the majority of the pancreatic islet cells, with respect to the control group. As a result, MCE exhibited significant antihyperglycemic effect and protected β-cells in STZ-diabetic rats, in a dose-dependent manner, and diminished the hyperglycemia-related oxidative stress.

Antinociceptive, anti-inflammatory, and antipyretic properties of an aqueous extract of Dicranopteris linearis leaves in experimental animal models

Abstract: This study was performed out to establish the antinociceptive, anti-inflammatory, and antipyretic properties of an aqueous extract of Dicranopteris linearis leaves in experimental animals. The antinociceptive activity was measured using the abdominal constriction, hot plate, and formalin tests. The anti-inflammatory and antipyretic activities were measured using the carrageenan-induced paw edema and brewer’s yeast-induced pyrexia tests, respectively. The extract, obtained after 72 h soaking of the air-dried leaves in distilled water and then prepared in the doses of 13.2, 66.0, 132.0, and 660.0 mg/kg, was administered subcutaneously 30 min before subjecting the animals to the assays mentioned above. Generally, the extract, at all doses used, was found to have significant (P < 0.05) concentration-independent antinociceptive, anti-inflammatory, and anti-pyretic activity. In conclusion, the aqueous extract of D. linearis has antinociceptive, anti-inflammatory, and antipyretic activity, supporting previous claims of its traditional use by the Malays to treat various ailments, particularly fever.

Alkaloids from the seeds of Peganum harmala showing antiplasmodial and vasorelaxant activities

Abstract: Bioassay-guided purification from the seeds of Peganum harmala led to the isolation of harmine (1), harmaline (2), vasicinone (3), and deoxyvasicinone (4). Harmine (1) and harmaline (2) showed a moderate in vitro antiplasmodial activity against Plasmodium falciparum. Quinazoline alkaloid, vasicinone (3), showed a vasorelaxant activity against phenylephrine-induced contraction of isolated rat aorta.

Evaluation of Sesbania grandiflora for antiurolithiatic and antioxidant properties

Abstract: In the indigenous system of medicine in India, the plant Sesbania grandiflora is claimed to be useful for various ailments, and one such use is for the treatment of renal calculi. The major purpose of this study is to investigate the potential of S. grandiflora in the treatment of renal calculi. The leaf juice of S. grandiflora was evaluated for median lethal dose, gross behavioral changes, antiurolithiatic and antioxidant activities. The antiurolithiatic activity was evaluated by a calculi-producing diet model, using gentamicin (subcutaneously) and 5% ammonium oxalate in rat feed to induce calcium oxalate-type stones. The parameters monitored in the present study are calcium and oxalate deposition in the kidney, kidney weights, urinary excretion of calcium and oxalate. The in vivo antioxidant parameters lipid peroxidation, glutathione reductase and catalase were monitored. The plant juice was also evaluated for scavenging of nitric oxide and 2-diphenyl-2-picryl hydrazyl free radicals. The leaf juice of S. grandiflora was safe orally and exhibited no gross behavioral changes except for an increase in urination. The leaf juice of S. grandiflora showed significant antiurolithiatic activity against calcium oxalate-type stones and also exhibited antioxidant properties. The results obtained in this study provide evidence for the efficacy of the leaf juice of S. grandiflora as antiurolithiatic agent.

Polyphenolic compounds isolated from the leaves of Myrtus communis

Abstract: Four hydrolyzable tannins [oenothein B (1), eugeniflorin D2 (2), and tellimagrandins I (3) and II (4)], two related polyphenolic compounds [gallic acid (5) and quinic acid 3,5-di-O-gallate (6)], and four myricetin glycosides [myricetins 3-O-β-d-xyloside (7), 3-O-β-d-galactoside (8), 3-O-β-d-galactoside 6″-O-gallate (9), and 3-O-α-l-rhamnoside (10)] were isolated from the leaves of Myrtus communis. Antioxidant activities of the isolated compounds were evaluated by 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assay.

Antinociceptive and anti-inflammatory activities of the aqueous extract of Kaempferia galanga leaves in animal models.

Abstract: This study was performed to determine the antinociceptive and anti-inflammatory activities of aqueous extract of Kaempferia galanga leaves using various animal models. The extract, in the doses of 30, 100, and 300 mg/kg, was prepared by soaking (1:10; w/v) the air-dried powdered leaves (40 g) in distilled water (dH(2)O) for 72 h and administered subcutaneously in mice/rats 30 min prior to the tests. The extract exhibited significant (P < 0.05) antinociceptive activity when assessed using the abdominal constriction, hot-plate and formalin tests, with activity observed in all tests occurring in a dose-dependent manner. Furthermore, the antinociceptive activity of K. galanga extract was significantly (P < 0.05) reversed when prechallenged with 10 mg/kg naloxone. The extract also produced a significantly (P < 0.05) dose-dependent anti-inflammatory activity when assessed using the carrageenan-induced paw-edema test. In conclusion, this study demonstrated that K. galanga leaves possessed antinociceptive and anti-inflammatory activities and thus supports the Malay's traditional uses of the plant for treatments of mouth ulcer, headache, sore throat, etc.

Comparison of the major flavonoid content of S. baicalensis, S. lateriflora, and their commercial products

Abstract: According to the notification for definition of pharmaceuticals from the Director-General of the Pharmaceutical and Food Safety Bureau, Ministry of Health Labour and Welfare of Japan, the roots of Scutellaria baicalensis (Chinese skullcap) and S. lateriflora (skullcap) are classified as “the raw materials exclusively used as pharmaceuticals”, but their aerial parts are classified as “non-pharmaceuticals” so, in principle, there are no health claims for these materials and no descriptions of drug-like dosages or administration directions. Dried root of S. baicalensis is also registered in Japanese Pharmacopoeia XV as scutellaria root. Scutellaria root is considered to have the adverse drug reactions of interstitial pneumonia and drug-induced hepatopathy in kampo medicines (Japanese traditional herbal formulations), and baicalin, its major constituent, is considered to be the cause of the adverse reaction. This study was conducted to evaluate the validity of this borderline between pharmaceuticals and non-pharmaceuticals by analyzing the amounts of four flavonoids, including baicalin, in the roots, stems, and leaves of S. baicalensis and S. lateriflora, and in the commercial products herbal tea and dietary supplements prepared from S. lateriflora. These flavonoids were found in the root of S. baicalensis; its aerial parts, however, did not contain them. On the other hand, the amounts of those flavonoids in the aerial parts of S. lateriflora were larger than in the root. Herbal tea and dietary supplements of S. lateriflora obtained commercially also contained those flavonoids, and the dietary supplements contained amounts of them comparable with that in kampo medicine. These results suggest that classification that the aerial parts of S. lateriflora as non-pharmaceuticals in Japan needs reconsideration.

In vitro antimalarial activity of prenylated flavonoids from Erythrina fusca

Abstract: Ethyl acetate (EtOAc) extract from the stem bark of Erythrina fusca showed a antimalarial activity against the multi-drug-resistant strain (K1) of Plasmodium falciparum, and six flavonoids, lupinifolin (1), citflavanone (2), erythrisenegalone (3), lonchocarpol A (4), liquiritigenin (5), and 8-prenyldaidzein (6), were isolated from the extract. Diprenylated flavanone 4 showed a notable antimalarial activity (IC50; 1.6 μg/mL); however 1 and 3 did not show the activity, even though these compounds possessed prenylated substitution.

Studies on the constituents from the fruits of Phaleria macrocarpa

Abstract: From the fruits of Phaleria macrocarpa, icariside C3 (1), phalerin (2), and mangiferin (3) were isolated and their structures were identified on the basis of spectroscopic data. Icariside C3 (1) showed a slow vasorelaxant activity against noradrenaline-induced contraction of isolated rat aorta. The structure of phalerin (2) was revised as 2,4′,6-trihydroxy-4-methoxybenzophenone-2-O-β-d-glucoside.

5-Hydroxymethyl-2-furfural, a clinical trials agent for sickle cell anemia, and its mono/di-glucosides from classically processed steamed Rehmanniae Radix

Abstract: Rehmanniae Radix (Di Huang) is one of the most important traditional Chinese medicines (TCM), and is used for multiple therapeutic purposes. In our investigation of the chemical constituents of Rehmanniae Radix, steamed roots were prepared by the classical processing method. Reversed-phase HPLC of the 50% MeOH extract of steamed Rehmanniae Radix yielded three 5-hydroxymethylfurfural derivatives. The new furfural disaccharide 5-(α-d-glucopyranosyl-(1→6)-α-d-glucopyranosyloxymethyl)-2-furancarboxaldehyde (1) was isolated and characterized, together with its known aglycone 5-hydroxymethyl-2-furfural (3), which is currently in sickle cell anemia Phase I clinical trials, and its corresponding monosaccharide 5-(α-d-glucopyranosyloxymethyl)-2-furancarboxaldehyde (2), which was isolated as a natural product for the first time. The presence of these three compounds, particularly 3, which were not found in the unprocessed extract of Rehmanniae Radix, could substantiate the traditional medicinal use of steamed Rehmanniae Radix.

Thin layer chromatography analysis of antioxidant constituents of lichens from Antarctica.

Abstract: Antioxidant agents against reactive oxygen species can be used for several cosmetic and medicinal applications. Methanol–water (90:10 v/v) extracts of five polar lichen species—namely Stereocaulon alpinum Laurer (Stereocaulaceae); Ramalina terebrata Hook and Taylor (Ramalinaceae); Caloplaca sp. (Teloschistaceae); Lecanora sp. (Lecanoraceae); and Caloplaca regalis (Vain.)Zahlbr (Teloschistaceae) from King George Island (Antarctica)—were analyzed using thin layer chromatography (TLC) followed by a DPPH (2,2-diphenyl-1-picrylhydrazyl) spray technique. The experimental data showed that 33–50% of the major constituents of the test extracts were active antioxidants. Stereocaulon alpinum and R. terebrata showed a higher number (50%) of antioxidant constituents, although their activities were comparatively weak. The strength of antioxidant activity in terms of discoloration of DPPH was shown to be stronger by the constituents of S. alpinum, C. regalis and C. sp. In addition, phenolic content in these Antarctic lichen extracts was in the range of 17–47 mg/g, supporting the antioxidant data of TLC analysis. Thus, these results suggest that Antarctic lichen contains a variety of strong antioxidant constituents. Therefore, further study of the laboratory culture of lichen is warranted to investigate possible commercial production, followed by isolation and characterization of the active antioxidant agents, which can be used against various oxidative stress-related diseases.

Two new flavonoids from Centella asiatica (Linn.)

Abstract: Two new flavonoids named castilliferol 1 and castillicetin 2, as well as a known compound, isochlorogenic acid 3, were isolated from the whole plant of Centella asiatica. Isolates 1 and 2 exhibited good antioxidant activity using 2,2-diphenyl-1-picryl hydrazyl radical solution with IC(50) values of 23.10 and 13.30, respectively. The structures of these isolates were determined by analytical and spectral data, including 1-D and 2-D NMR spectra.

Efficacy of extracting solvents to chemical components of kava (Piper methysticum) roots

Abstract: The chemical composition of kava (Piper methysticum) lactones and various phytochemicals obtained following the sonication of ground kava roots extracted in the solvents hexane, chloroform, acetone, ethanol, methanol and water, respectively, was analyzed. Eighteen kava lactones, cinnamic acid bornyl ester and 5,7-dimethoxy-flavanone, known to be present in kava roots, were identified, and seven compounds, including 2,5,8-trimethyl-1-naphthol, 5-methyl-1-phenylhexen-3-yn-5-ol, 8,11-octadecadienoic acid-methyl ester, 5,7-(OH)(2)-4'-one-6,8-dimethylflavanone, pinostrobin chalcone and 7-dimethoxyflavanone-5-hydroxy-4', were identified for the first time. Glutathione (26.3 mg/g) was found in the water extract. Dihydro-5,6-dehydrokavain (DDK) was present at a higher level than methysticin and desmethoxyyagonin, indicating that DDK is also a major constituent of kava roots. Acetone was the most effective solvent in terms of maximum yield and types of kava lactones isolated, followed by water and chloroform, whereas hexane, methanol, and ethanol were less effective as solvents. Total phenolic and antioxidant activity varied among the extracting solvents, with acetone and chloroform producing the highest effects, followed by water, while methanol, ethanol and hexane were less effective.

Pharmacologically active compounds in the Anoectochilus and Goodyera species

Abstract: The extract of Anoectochilus formosanus showed significant activity in decreasing the levels of the cytosolic enzymes LDH, GOT, and GPT, and the result demonstrated that A. formosanus possessed prominent hepatoprotective activity against CCl4-induced hepatotoxicity. Moreover, in the results of the test using aurothioglucose-induced obese mice, the extract showed a significant antihyperliposis effect. A. formosanus grown in the wild and propagated by tissue culture contain ten compounds, including a major known component, (3R)-3-(β-d-glucopyranosyloxy)butanolide (kinsenoside; 1), and two new components, (3R)-3-(β-d-glucopyranosyloxy)-4-hydroxybutanoic acid (2) and 2-[(β-d-glucopyranosyloxy)methyl]-5-hydroxymethylfuran (3), along with the known compounds, isopropyl-β-d-glucopyranoside (4), (R)-3,4-dihydroxybutanoic acid γ-lactone (5), 4-(β-d-glucopyranosyloxy) benzyl alcohol (6), (6R,9S)-9-(β-d-glucopyranosyloxy)megastigma-4,7-dien-3-one (7), and (3R)-3-(β-d-glucopyranosyloxy)-4-hydroxybutanolide (8). Since a higher concentration of kinsenoside (1) was detected in the crude drugs A. formosanus and A. koshunensis by high-performance liquid chromatography (HPLC) analysis, we proved a simple purification system for kinsenoside (1), giving 180 mg of kinsenoside (1) from 1 g of dried samples for further pharmacological experiments. In an anti-hyperliposis assay using high-fat-diet rats, 1 significantly reduced the weights of the body and the liver, and also decreased the triglyceride level in the liver compared to those of control rats. On the other hand, the epimer of 1, (3S)-3-(β-d-glucopyranosyloxy)butanolide, goodyeroside A (9), which was isolated from the Goodyera species, had no effect for anti-hyperliposis. In aurothioglucose-induced obese mice, 1 suppressed the body and liver weight increase, significantly ameliorated the triglyceride level in the liver, and also reduced the deposition of uterine fat pads. The anti-hepatoxic activities of 9 and goodyerosides B (10) were studied on injury induced by CCl4 in primary cultured rat hepatocytes by measuring the levels of LDH, GOT, and GPT. In the CCl4-treated control group, there were marked increases in LDH, GOT, and GPT activities compared with the normal group. In contrast, these levels were suppressed in 9- and 10-treated groups. Goodyerin (11), a new typical flavone glycoside, exhibited a significant and dose-dependent sedative and anticonvulsant effect.

Inhibitory effect of the rhizomes of Alpinia officinarum on TPA-induced inflammation and tumor promotion in two-stage carcinogenesis in mouse skin

Abstract: The methanol extract of galangal (the rhizomes of Alpinia officinarum L.) exhibited remarkable antitumor-promoting activity on an in vivo two-stage carcinogenesis test of mice using 7,12-dimethylbenz[a]anthracene as an initiator and 12-O-tetradecanoylphorbol-13-acetate (TPA) as a promoter. Seven diarylheptanoids (1–7) were isolated and identified from the active fraction of the methanol extracts of the galangal. These compounds, 1–7, were evaluated for their inhibitory effects on TPA-induced inflammation (1 μg/ear) in mice. These compounds (1–7) tested showed marked anti-inflammatory effects, with a 50% inhibitory dose of 0.8–2.7 μmol/ear.

Antidiarrhoeal activity of the standardised extract of Cinnamomum tamala in experimental rats

Abstract: The present study was designed to investigate the antidiarrhoeal potential of 50% ethanolic extract of Cinnamomum tamala on experimentally induced castor oil diarrhoea, gastric emptying of phenol red meal, gastrointestinal transit of charcoal meal and in vitro mast cell degranulation activity. C. tamala extract (25, 50 and 100 mg/kg, orally) produced a dose-dependent reduction in the total amount of faecal matter in castor oil-induced diarrhoea. The mean distance travelled by charcoal meal at 50 and 100 mg/kg of extract showed a significant reduction in the secretion of gastrointestinal fluid accumulation by 32.5–65.0%. The Na+ and K+ concentrations on castor oil-induced fluid accumulation showed a greater inhibitory effect on Na+ levels than on K+ concentrations. C. tamala significantly reduced the lipid peroxidation (P < 0.001) and increased the catalase (P < 0.01) activity in comparison to the castor oil-induced groups. C. tamala leaf extract did not show any significant effect at a higher dose (15 mg/ml) on mast cell degranulation. However, the extract in the dose of 5 and 10 mg/ml conferred significant mast cell protective action (P < 0.001). The percentage of eugenol in extract is 3.8% w/w, and total tannin is 247.5 mg/g. The result indicates the Indian spice C. tamala is useful for diarrhoea.

Constituents from leaves of Apocynum venetum L.

Abstract: An analysis using HPLC–MS revealed that an extract from dried leaves of Apocynum venetum L. contained more than 15 kinds of phenolic constituents. Two malonated flavonol glycosides were further isolated, and their structures were determined to be quercetin 3-O-(6′′-O-malonyl)-β-d-glucoside (1) and quercetin 3-O-(6′′-O-malonyl)-β-d-galactoside (2) by NMR spectroscopic analysis. This is the first report describing the isolation of these malonated flavonol glycosides from A. venetum L. Both glycosides showed strong scavenging activity against 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical.

A rapid method for isolation of piperine from the fruits of Piper nigrum Linn.

Abstract: A simple, rapid and efficient method has been developed for the isolation of piperine from the fruits of Piper nigrum. The method involves extraction of the fruit powder with glacial acetic acid, from which piperine is partitioned into chloroform and subsequently crystallized. The identity of the compound was confirmed by its melting point, comparison of UV, IR, and mass spectral data with those from a reference standard, and co-chromatography with the reference standard using thin-layer chromatography (TLC). The purity of the compound was ascertained by TLC, by recording UV absorption spectra at the start, middle, and end positions of the spot on the plate, and by differential scanning calorimetry (DSC).

Hepatoprotective and antioxidant activity of methanol extract of Ficus glomerata.

Abstract: The present study was carried out to evaluate Ficus glomerata extracts for antioxidant and hepatoprotective properties. The methanol extract of the bark of F. glomerata showed potent in vitro antioxidant activity when compared to the root methanol extract. In the in vivo studies, the CCl(4) treated control rats showed a significant alteration in the levels of antioxidant and hepatoprotective parameters. The methanol extract of the bark when given orally along with CCl(4) at the doses of 250 and 500 mg/kg body weight showed a significant reversal of these biochemical changes towards the normal when compared to CCl(4)-treated control rats in serum, liver and kidney. The results were comparable to those observed for standard sylimarin. Histological studies also confirmed the same. The results indicated the potent hepatoprotective and antioxidant nature of the bark extract.

Potential anthelmintics: polyphenols from the tea plant Camellia sinensis L. are lethally toxic to Caenorhabditis elegans

Abstract: A novel gallate of tannin, (-)-epigallocatechin-(2 beta-->O-->7',4 beta-->8')-epicatechin-3'-O-gallate (8), together with (-)-epicatechin-3-O-gallate (4), (-)-epigallocatechin (5), (-)-epigallocatechin-3-O-gallate (6), and (+)-gallocatechin-(4 alpha-->8')-epigallocatechin (7), were isolated from the tea plant Camellia sinensis (L.) O. Kuntze var. sinensis (cv., Yabukita). The structure of 8, including stereochemistry, was elucidated by spectroscopic methods and hydrolysis. The compounds, along with commercially available pyrogallol (1), (+)-catechin (2), and (-)-epicatechin (3), were examined for toxicity towards egg-bearing adults of Caenorhabditis elegans. The anthelmintic mebendazole (9) was used as a positive control. Neither 2 nor 3 were toxic but the other compounds were toxic in the descending order 8, 7 approximately 6, 9, 4, 5, 1. The LC(50) (96 h) values of 8 and 9 were evaluated as 49 and 334 micromol L(-1), respectively. These data show that many green tea polyphenols may be potential anthelmintics.

Microbial metabolism of soy isoflavones by human intestinal bacterial strains.

Abstract: Intestinal bacteria play an important role for the metabolism of soy isoflavonoids. When soy foods are consumed, the soy isoflavone glucosides are metabolized into their aglycones and the related isoflavonoids by intestinal bacteria. We designed an in vitro microbial metabolic system using 29 commercially available human intestinal bacterial strains and elucidated the metabolism of soy isoflavone glucosides. The strains were classified into three categories, which were 14 facultative anaerobes, 13 obligate anaerobes, and 2 aerobes. Almost all facultative anaerobe strains metabolized soy isoflavone glucosides to their aglycones. The ratio of metabolism from glucoside to aglycone was different in each strain. Contrary to the facultative anaerobes, some of the obligate anaerobes did not metabolize soy isoflavone glucosides at all. Both the aerobic bacteria hardly metabolized soy isoflavone glucosides. The bacterial growth speed might show good correlation to the metabolizing speed of both glucosides. Therefore, the speed of metabolism would be different in each bacterial strain, too.

Anticarcinogenic compounds in the Uzbek medicinal plant, Helichrysum maracandicum.

Abstract: An ethanol extract of Helichrysum maracandicum showed antiproliferative activity against cultured cells of SENCAR mouse in an in vitro assay, and activity-guided fractionation of the extract resulted in the isolation of isosalipurposide as an active substance. Naringenin chalcone, the aglycone of isosalipurposide, also showed strong antiproliferative activity. An in vivo assay of two-stage carcinogenesis on mouse skin revealed that epidermal application of isosalipurposide resulted in delayed formation of papillomas. Western blot analysis showed that the expression of p38 mitogen-activated protein kinase was suppressed by the administration of naringenin chalcone or isosalipurposide, which might be related to the anticarcinogenic activity.

Antitubercular triterpenes and phytosterols from Pandanus tectorius Soland. var. laevis.

Abstract: Bioassay-guided chromatographic purification of the antitubercular chloroform extract of Pandanus tectorius Soland. var. laevis leaves afforded a new tirucallane-type triterpene, 24,24-dimethyl-5β-tirucall-9(11),25-dien-3-one (1), squalene and a mixture of the phytosterols stigmasterol and β-sitosterol. Microplate Alamar Blue Assay (MABA) showed that 1 inhibited the growth of Mycobacterium tuberculosis H37Rv with a MIC of 64 μg/mL, while squalene and the sterol mixture have MICs of 100 and 128 μg/mL, respectively.

Chemical and biologically active constituents of Pteris multifida

Abstract: A new compound, 4-caffeoyl quinic acid 5-O-methyl ether (2), together with 12 known compounds—identified as (2R,3R)-pterosin L 3-O-β-d-glucopyrannoside (3), β-sitosterol β-d-glucopyranoside (4), apigenin 7-Ο-β-d-glucopyranoside (5), luteolin 7-Ο-β-d-glucopyranoside (6), sucrose (7), caffeic acid (8), pterosin C 3-Ο-β-d-glucopyranoside (9), pteroside C (10), 4,5-dicaffeoyl quinic acid (11), pteroside A (12), wallichoside (13) and (2S)-5,7,3′,5′-tetrahydroxyflavanone (14)—were isolated from Pteris multifida. The structure of the new compound was determined by means of physical, chemical and spectroscopic evidence. Compounds 5 and 6 were the main constituents of the plant, with yields of 0.19% and 0.16%, respectively. The cytotoxic activities of 2, 3, and 9–13 were evaluated against a human cell line (KB cells). Among the isolated compounds, pterosin C 3-Ο-β-d-glucopyrannoside (9) and 4,5-dicaffeoylquinic acid (11) showed a significant selective cytotoxicity (IC50 2.35 and 5.38, respectively), while moderate activity was observed for compound 2 (IC50 12.3). The chemosystematics of Pteris species is also discussed.

New alkaloid from the aerial parts of Codonopsis clematidea.

Abstract: A new codonopsine-related alkaloid and 13 known compounds were isolated from the aerial parts of Codonopsis clematidea (Campanulaceae) The structure of the new compound was elucidated by two-dimensional nuclear magnetic resonance and other spectral examinations

Two new antibacterial norabietane diterpenoids from cyanobacteria, Microcoleous lacustris

Abstract: Two abietane diterpenes were isolated from cyanobacteria Microcoleous lacustris, 20-nor-3α-acetoxyabieta-5,7,9,11,13-pentaene and 20-nor-3α-acetoxy-12-hydroxy-abieta-5,7,9,11,13-pentaene. These compounds were assayed against Staphylococcus aureus, Staphylococcus epidermidis, Salmonella typhi, Vibrio cholerae, Bacillus subtilis, Bacillus cereus, Escherichia coli, and Klebsiella pneumoniae. Both compounds showed activity against S. aureus, S. epidermidis, S. typhi, and V. cholerae, but not against the other bacteria.

Studies on perilla, agarwood, and cinnamon through a combination of fieldwork and laboratory work.

Abstract: Fieldwork is one of the primary methods for studying medicinal plants and materials, and information thus obtained can be valuable for experiments performed in the laboratory. Meanwhile, results of experiments in the laboratory can be brought back to the field for verification and further investigation. A combination of field and laboratory work has led to effective progress in studies of medicinal plants in the field of pharmacognosy. However, the collection of samples with information through fieldwork is not easy, and it fundamentally requires a great deal of research experience. Geographical, ethnical, and political affairs often affect its performance, and to establish a good cooperative relationship with foreign localities is inevitably required. Beyond these difficulties, fieldwork can provide a framework for the research project and excellent and unique viewpoints concerning the target. This review article describes studies on perilla, agarwood, and cinnamon, focusing mainly on the results of fieldwork performed in Indochina on these species. All three of these medicinal plants contain essential oils, and their composition varieties, biosynthetic pathways, pharmacological activities, or induction mechanisms for production are principally investigated through shuttling between fieldwork and laboratory experiments.