3-O-ß-D-Glucopyranosyltheobroxide from Aerial Parts of Cowpea (Vigna unguiculata).

Theobroxide has been isolated from culture filtrates of Lasiodiplodia theobromae as a potato tuber-inducing compound. In this study, the metabolism of theobroxide was investigated using cowpea as an experimental model and [2H3-7]theobroxide as a substrate for analyzing a metabolite, which revealed that theobroxide applied exogenously to the roots was converted into 3-O-ß-D-glucopyranosyltheobroxide.

Bioconversion of proposed precursors into theobroxide and related compounds.

We have previously reported a tetraketide origin for theobroxide and its related compound. In the present study, bioconversion of natural and deuterium-labeled precursors of this proposed biosynthetic pathway by Lasiodipoldia theobromae was investigated. Theobroxide was quantified after bioconversion from each proposed precursor. The transformation of the isotopically labeled precursor to products was tracked by 2H NMR measurement.

Temperature regulates tuber-inducing lipoxygenase-derived metabolites in potato (Solanum tuberosum).

Temperature is one of the major environmental factors affecting potato tuberization. It has been suggested that lipoxygenase (LOX) mediates between temperature and tuber induction. In this study, the contents of the LOX-derived metabolites hydroperoxylinolenic acid (HPOT), jasmonic acid (JA), tuberonic acid (TA) and tuberonic acid glucoside (TAG) were analyzed in leaves of potatoes growing at different temperatures. At low, tuber-inducing temperature, endogenous levels of JA, TA and TAG rise, indicating their crucial role in tuber induction. The concentration of 13(S)-HPOT seems not to be directly affected by temperature. Instead, the molecule has only a short half-life in leaves and is readily metabolized.

Evaluation of the inhibitory activities of the extracts of Indonesian traditional medicinal plants against Plasmodium falciparum and Babesia gibsoni.

Twenty-four kinds of water extracts derived from 22 plants that are traditionally used for the treatment of malaria on Java Island, Indonesia, were screened for their antibabesial and antimalarial activities. Among the extracts, 8 extracts displayed strong antimalarial activity, with an inhibition range from 89.6 to 100%, and 15 showed strong antibabesial activity, with an inhibition range from 84.2 to 98.1%. The extracts of Achillea millefolium, Baeckea frutenscens, Brucea javanica, Curcuma xanthorrhiza, Strychnos lucida and Swietenia macrophylla showed both strong antibabesial and antimalarial activities. The antimalarial activities paralleled the antibabesial activities, but the converse was not true.

Novel potato micro-tuber-inducing compound, (3R,6S)-6-hydroxylasiodiplodin, from a strain of Lasiodiplodia theobromae.

A novel potato micro-tuber-inducing compound was isolated from the culture broth of Lasiodiplodia theobromae Shimokita 2. The structure of the isolated compound was determined as (3R,6S)-6-hydroxylasiodiplodin by means of spectroscopic analyses, the modified Mosher method, and chemical conversion. The compound showed potato micro-tuber-inducing activity at a concentration of 10(-4) M, using the culture of single-node segments of potato stems in vitro.

Anti-babesial compounds from Curcuma zedoaria.

Anti-babesial activity was confirmed in an extract of the bark of Curcuma zedoaria. The active ingredients were isolated, and their chemical structures were determined to be zedoalactones A, B, and C based on spectral data. Zedoalactone C is a hitherto unreported compound. The IC50 vales of these active compounds against Babesia gibsoni were compared with a standard drug, diminazene aceturate. The IC50 value of diminazene aceturate was 0.6 microg/mL, while those of zedoalactones A, B, and C were 16.5, 1.6 and 4.2 microg/mL, respectively.

Anti-babesial activity of some central kalimantan plant extracts and active oligostilbenoids from Shorea balangeran.

Bark extracts from a total of 22 species of Central Kalimantan plants were evaluated for their anti-babesial activity against Babesia gibsoni in vitro. Of these plant species, extracts of Calophyllum tetrapterum, Garcinia rigida, Lithocarpus sp., Sandoricum emarginatum, and Shorea balangeran showed more than 90% inhibition of the parasite growth at a test concentration of 1000 microg/mL. Activity-guided fractionation of the bark of S. balangeran (Dipterocarpaceae) led to the reisolation of oligostilbenoids, vaticanol A(1), B(2), and G(3). The structures were determined on the basis of spectral evidence. Compounds 1 and 3 showed complete inhibition on the growth of Babesia gibsoni in vitro at a concentration of 25 microg/mL, and compound 2 at concentration of 50 microg/mL.

Anti-babesial and anti-plasmodial compounds from Phyllanthus niruri.

Bioassay-guided fractionation of boiled aqueous extracts from the whole plant of Phyllanthus niruri led to the isolation of 1-O-galloyl-6-O-luteoyl-alpha-d-glucose (1), with IC(50) values of 4.7 microg/mL against Babesia gibsoni and 1.4 microg/mL against Plasmodium falciparum in vitro. The known compounds beta-glucogallin (2), quercetin 3-O-beta-d-glucopyranosyl-(2-->1)-O-beta-d-xylopyranoside (3), beta-sitosterol, and gallic acid were also isolated. Structures of these compounds were elucidated on the basis of their chemical and spectroscopic data.

Anti-fungal sesquiterpenoid from the root exudate of Solanum abutiloides.

The Solanum abutiloides plant is highly resistant to soil-borne pathogens such as Fusarium oxysporum f. sp. melongenae, Verticillium dahliae, and Ralstonia solanacearum. This species is utilized as a mating source of resistant cultivars and is also used as a rootstock. The root exudate of Solanum abutiloides was extracted from a soil system composed of charcoal and vermiculite. Anti-fungal activity was found in the extract, and an active ingredient was isolated. The chemical structure of the active compound was determined to be 3-beta-acetoxysolavetivone, a new sesquiterpenoid. The anti-fungal activity of 3-beta-acetoxysolavetivone examined by the inhibition of spore germination of Fusarium oxysporum was close to that of lubimin, and higher than that of solavetivone.

Effects of Central Kalimantan plant extracts on intraerythrocytic Babesia gibsoni in culture.

The inhibitory effects of 45 plant extracts selected from Central Kalimantan, Indonesia on Babesia gibsoni in vitro and their acute toxicity to mice were evaluated. Of these plant extracts studied, Arcangelisia flava, Curcuma zedoaria, Garcinia benthamiana, Lansium domesticum and Peronema canescens were found to have appreciable antibabesial activity with IC50 values from 5.3 to 49.3 microg/ml without acute toxicity in mice at the intraperitoneal dose of 0.7 g/kg of body weight.

Effects of theobroxide, a natural product, on the level of endogenous jasmonoids.

The natural potato microtuber inducing substance, theobroxide, strongly induces the formation of tuber of potato (Solanum tuberosum L.) and flower bud of morning glory (Pharbitis nil) plants under non-inducing conditions (long days) (Yoshihara et al., 2000). In the present study, theobroxide was evaluated for its effect on the level of endogenous jasmonoids in different tissues of such two plants. An in vitro bioassay using cultures of single-node segments of potato stems was performed with the supplement of theobroxide in the medium. The endogenous jasmonic acid (JA) and its analogue tuberonic acid (TA, 12-hydroxyjasmonic acid) in segments and microtubers were quantitatively analyzed. The increase in the endogenous JA level caused by theobroxide was observed in both segments and microtubers. Endogenous TA was only detected in segments, and the content increased with the concentration of theobroxide. As for morning glory, the whole plant was sprayed with theobroxide for 1 approximately 5 weeks under different photoperiods and endogenous JA in the leaves was quantitatively analyzed. Theobroxide spraying increased the level of endogenous JA in the leaves of the plants grown under both long and short days.

DPPH radical scavengers from dried leaves of oregano (Origanum vulgare).

1,1-Dipehnyl-2-picrylhydrazyl (DPPH) radical scavenging activities were found in the extract of dried leaves of oregano (Origanum vulgare). The water-soluble active ingredients were isolated, and their structures were determined to be 4'-O-beta-D-glucopyranosyl-3',4'-dihydroxybenzyl protocatechuate and 4'-O-beta-D-glucopyranosyl-3',4'-dihydroxybenzyl 4-O-methylprotocatechuate by (1)H-, (13)C-NMR, DEPT, HMQC, and HMBC spectral analyses, and by NOE experiments. The DPPH radical scavenging activities of these compounds were compared with those of rutin, quercetin and rosmarinic acid at a concentration of 2 x 10(-5) M. The scavenging activity of 4'-O-beta-D-glucopyranosyl-3',4'-dihydroxybenzyl protocatechuate was almost the same as that of quercetin and rosmarinic acid, but that of 4'-O-beta-D-glucopyranosyl-3',4'-dihydroxybennzyl 4-O-methylprotocatechuate was less than that of quercetin, rosmarinic acid and 4'-O-beta-D-glucopyranosyl-3',4'-dihydroxybenzyl protocatechuate. The amount of 4'-O-beta-D-glucopyranosyl-3',4'-dihydroxybenzyl protocatechuate was estimated to be 3.8 mg/1 g of dried leaves by an HPLC analysis.

Metabolism of deuterium-labeled jasmonic acid and OPC 8:0 in the potato plant (Solanum tuberosum L.).

The metabolism of deuterium-labeled (+/-)-jasmonicacid and 3-oxo-2-[(Z)pent-2'-enyl]-cyclopentan-1- octanoic acid in potato (Solanum tuberosum L.) was examined by using cultures of potato single-node stems. Deuterium-labeled (+/-)-jasmonic acid and 3-oxo-2-[(Z) pent-2'-enyl]cyclopentan-1-octanoic acid, which had been prepared from commercially available methyl (+/-)-jasmonate, were fed to the cultures, and the metabolites were extracted from the plants and analyzed by a liquid chromatography-selected ion monitoring system. The metabolism of deuterium-labeled (+/-)-jasmonic acid and 3-oxo-2-[(Z)-2'-pentenyl]cyclopentan-1-octanoic acid to 5' and 4'-O-glucopyranosyloxyjasmoic acids was strongly suggested.

Isolation and identification of sodium 2-propenyl thiosulfate from boiled garlic (Allium sativum) that oxidizes canine erythrocytes.

Sodium 2-propenyl thiosulfate was identified in boiled garlic (Allium sativum). When canine erythrocytes were incubated with sodium 2-propenyl thiosulfate, the methemoglobin concentration and Heinz body percentage in erythrocytes were both increased, indicating that the compound induced oxidative damage in canine erythrocytes. It seems that this compound is one of the causative agents of garlic-induced hemolysis in dogs.

Organosulfur compounds from garlic (Allium sativum) oxidizing canine erythrocytes.

The sulfurous acid ester, trans-sulfurous acid allyl ester 3-allylsulfanyl-allyl ester 8, along with two known thiosulfinates was isolated from the aqueous ethanol extract of garlic (Allium sativum). The chemical structure of 8 was determined on the basis of spectroscopic data including high resolution mass and two-dimensional NMR techniques. All of these compounds induced methemoglobin formation in a canine erythrocyte suspension in vitro resulting in the oxidation of canine erythrocytes. This is the first report of sulfurous acid ester showing oxidant activity in canine erythrocytes.

Isolation and identification of organosulfur compounds oxidizing canine erythrocytes from garlic (Allium sativum).

Five compounds oxidizing canine erythrocytes were isolated from an aqueous ethanol garlic extract by silica gel column chromatography and preparative thin-layer chromatography. On the basis of nuclear magnetic resonance, infrared spectroscopy, and mass spectrometry, they were identified as three known compounds: bis-2-propenyl trisulfide (1), bis-2-propenyl tetrasulfide (2), and bis-2-propenyl pentasulfide (3) as well as two novel compounds, bis-2-propenyl thiosulfonate (4) and trans-sulfuric acid allyl ester 3-allylsulfanyl-allyl ester (5). A mixture of compounds 1-3 and compounds 4 and 5 induced methemoglobin formation in canine erythrocyte suspension in vitro resulting in the oxidation of canine erythrocytes. These groups of characteristic organosulfur compounds contained in garlic probably contribute to oxidations in blood. The constituents of garlic have the potential to oxidize erythrocytes and hemoglobin, suggesting that foods containing quantities of garlic should be avoided for feeding dogs.