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An extensive phytochemical analysis of the saponin content has been undertaken on leek, Allium porrum L., sown and collected at different seasons. As a result of this investigation, eight saponins (1-8) have been isolated, four of them (5-8) being novel compounds. Compounds 5 and 6, possessing the same tetrasaccharide moiety of compounds 1 and 3, display very unusual spirostane aglycones, 12-ketoporrigenin and 2,12-diketoporrigenin (named porrigenin C), respectively, recently isolated for the first time as free sapogenin in the same plant. Compounds 7 and 8 are rare cholestane bidesmosides possessing a di- and trisaccharide residues linked to a polyhydroxycholesterol aglycone, respectively. The structures of the isolated compounds have been determined by nondegradative spectroscopic analysis, mainly based on NMR. All the eight saponins isolated from leek were tested for their cytotoxic activity against two different cell lines in vitro, and compounds 1, 2, and 6 resulted particularly active.

The structures of eight anthocyanins have been determined in acidified methanolic extract of pale-purple flowers of chive, Allium schoenoprasum. Four of them have been identified as the anthocyanin-flavonol complexes (cyanidin 3-O-beta-glucosideAII) (kaempferol 3-O-(2-O-beta-glucosylFIII-beta-glucosideFII)-7-O-beta-gl ucosiduronic acidFIV) malonateAIII (AII-6-->AIII-1, FIV-2-->AIII-3), 1, (cyanidin 3-O-(3-O-acetyl-beta-glucosideAII) (kaempferol 3-O-(2-O-beta-glucosylFIII-beta-glucosideFII)-7-O-beta-gl ucosiduronic acidFIV) malonateAIII (AII-6-->AIII-1, FIV-2-->AIII-3), 2, and their 7-O-(methyl-O-beta-glucosiduronateFIV) analogous, 3 and 4. Pigments 1 and 2 are the first final identification of covalent complexes between an anthocyanin and a flavonol, while 3 and 4 are formed during the isolation process. The other four anthocyanins (5-8) were found to be the 3-acetylglucoside, 3-glucoside, 3-(6-malonylglucoside) and 3-(3,6-dimalonylglucoside) of cyanidin. The three latter pigments have earlier been identified as the major anthocyanins of the chive stem. The covalent anthocyanin-flavonol complexes show intramolecular association between the anthocyanidin (cyanidin) and flavonol (kaempferol) units, which influence the colour.

Objective: To establish an Ehrlich reaction-colorimetry method for determining furostanol saponins in Bulbus Allii Macroste., Method: Based on the coloration reaction between furostanol saponins and p-dimethylaminobenzaldehyde, the UV detection wavelength used was 515 nm, and the optimum conditions were selected on homogeneous design principle., Result: The standard curve of macrostemonoside G was linear in the concentration range of 0.1975-0.9880 mg.ml-1. The average recovery was 97.7% (RSD = 3.65%)., Conclusion: The method is rapid, accurate and easy to operate.

Investigation of the Chinese crude drug "Xiebai," the bulbs of Allium chinense G. Don (Liliaceae), led to the isolation of 2 saponins, xiebai-saponin I (laxogenin 3-O-beta-xylopyranosyl (1-->4)-[alpha-arabinopyranosyl (1-->6)-beta-glucopyranoside) (1) and laxogenin 3-O-alpha-arabinopyranosyl (1-->6)-beta-glucopyranoside (2), and the aglycone, laxogenin (3), together with 2 chalcones, isoliquiritigenin (4) and isoliquiritigenin-4-O-glucoside (5), and beta-sitosterol glucoside (6). Compounds 1-5 were tested in vitro for their inhibitory effect on the 12-O-tetradecanoylphorbol-13-acetate (TPA)-stimulated 32Pi-incorporation into phospholipids of HeLa cells. In addition to this, laxogenin (3) was proven to have an antitumor-promoting activity in a two-stage lung carcinogenesis experiment.

Objective: To study the chemical constituents in the seed of Allium tuberosum., Method: Chromatography and spectral analysis were used to isolate the constituents and elucidate their structures., Result: Five compounds were isolated from the alcohol extracts of the seeds and identified as nicotianoside C, (22S)-cholest-5-ene-1 beta, 3 beta, 16 beta, 22-tetrol-1-O-alpha-L-rhamnopyranosyl-16-O-beta-D-glucopyranoside, daucosterol, adenosine and thymidine., Conclusion: All the compounds were isolated from the seed of this plant for the first time.

The intravenous administration of a purified fraction (6 microg/kg) to anaesthesized dogs was followed by a significant biphasic diuretic and natriuretic response which reached a maximum at 180 min after injection. Chloride, but not potassium ions, followed the natriuretic profile. No changes were observed in arterial blood pressure or in the electrocardiogram. The purified garlic fraction also induced an inhibitory dose-dependent effect on kidney Na, K-ATPase.

The effects of in vivo administration of naturally occurring organosulfur compounds (OSCs) from Allium species were studied on the activation of several mutagens. Male SPF Wistar rats were given p.o. one of either diallyl sulfide (DAS), diallyl disulfide (DADS), dipropyl sulfide (DPS) or dipropyl disulfide (DPDS) during 4 consecutive days and the ability of hepatic S9 and microsomes from treated rats to activate benzo[a]pyrene (BaP), cyclophosphamide (CP), dimethylnitrosamine (DMN), N-nitrosopiperidine (N-PiP) and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) was determined in the Ames test. Administration of DAS, DPS and DPDS resulted in a significant increase of the activation of BaP, CP, N-PiP and PhIP mediated by S9 and microsomes while DADS treatment only increased the mutagenicity of PhIP. In contrast, S9 from DADS-treated rats significantly inhibited the mutagenicity of N-PiP and BaP. DAS, DADS and DPS strongly inhibited DMN mutagenicity while DPDS enhanced it. To understand the mechanisms underlying these effects, the modifications of the activities of specific isozymes of CYP involved in the activation of these mutagens were studied. DAS, DPS and DPDS strongly enhanced pentoxyresorufin O-dealkylase (PROD) activity related to CYP2B and slightly increased ethoxyresorufin O-deethylase (EROD) and methoxyresorufin O-demethylase (MROD) activities related to CYP1A family. DADS exerted the same effects than other OSCs but to a lesser extent. p-Nitrophenol hydroxylase (PNPH) activity related to CYP2E1 was inhibited by DAS and DADS, whereas DPDS significantly increased this activity. Hence, the effects of OSCs on the mutagenicity of several genotoxic compounds are mediated by modification (enhancement or inhibition) of specific CYP involved in their activation.

Three new spirostanol steroidal oligoglycosides, together with a known oligoglycoside, were obtained from the seeds of Allium tuberosum after enzymatic hydrolysis of furostanol saponin fraction by beta-glucosidase. On the basis of spectroscopic analysis, the structure of new spirostanol oligoglycosides were elucidated as (25S)-spirost-5-ene-2alpha,3beta-diol 3-O-alpha-L-rhamnopyranosyl-(1-->4)-[alpha-L-rhamnopyranosyl-(1-->2)]-be ta-D-glucopyranoside, (25S)-spirostane-3beta,5beta,6alpha-triol 3-O-alpha-L-rhamnopyranosyl-(1-->4)-beta-D-glucopyranoside, and (25S)-5beta-spirostane-3beta,6alpha-diol 3-O-alpha-L-rhamnopyranosyl-(1-->4)-beta-D-glucopyranoside.

The content of S-alk(en)ylcysteine sulfoxides, important nonvolatile flavor precursors, was determined in 15 different Allium species by means of gas chromatography. The method employed is based on derivatization of S-alk(en)ylcysteine sulfoxides with ethyl chloroformate followed by their reduction with sodium iodide. The total content of S-alk(en)ylcysteine sulfoxides varied considerably in the wide range between 0.02 and 1.3% fresh weight. Not only the total content but also relative proportions of individual derivatives varied to a great extent. A novel S-alkylcysteine derivative, S-ethylcysteine sulfoxide (ethiin), not previously reported to occur in Allium species, was found in most of the samples examined in trace amounts. None of the other S-alk(en)ylcysteine sulfoxides, for example, isopropyl, (Z)-1-propenyl, butyl, or pentyl, were detected in any of the samples analyzed, limiting possible levels of each of these components to

Garlic components are known to modulate certain immune functions. However, mechanisms of their action are not sufficiently elucidated. This study was, therefore, undertaken to examine the effects of aqueous and ethanolic extracts prepared from a garlic powder sample on proliferation of rat spleen lymphocytes in culture. Cells were stimulated with the combination of phorbol myristate acetate (PMA) and a Ca ionophore (A23187) or R73 monoclonal antibody (mAb) directed to the alphabeta chain of T cell receptor. It has been shown that both extracts significantly stimulated proliferation of lymphocytes. The effect correlated with upregulation of the Interleukin 2 receptor alpha (IL-2R alpha) expression and the increase in IL-2 production. Stimulation of IL-2 production by the extracts was higher in cultures with PMA/Ca ionophore than in cultures with R73 mAb. In contrast, both extracts stimulated production of IL-4 by splenocytes triggered by R73 mAb. The complete dependence of lymphocyte proliferation in cultures with R73 mAb and garlic extracts on IL-2 and IL-4 was demonstrated using neutralising mAbs to IL-2R alpha and IL-4. These results suggest that the potentiating effect of garlic extracts on lymphocyte proliferation in vitro differs depending on specific stimulators of cell proliferation and probably on the type of responding cells.

The aim of this study was to determine the effect of herb (Allium sp.) on biochemical changes of herby cheese produced in Turkey. Raw cows' milk was used for cheese manufacture. Five groups of cheeses, containing 0 (as control), 0.5, 1, 2, and 3% herb, were produced and coded as K, A, B, C, and D respectively. All cheese groups were ripened at 8 degrees C for 90 days. Samples were taken from cheeses after 3, 15, 30, 60 and 90 days, and analysed for lipolysis (as acid degree value) and proteolysis (water-soluble nitrogen, TCA-soluble nitrogen, and PTA-soluble nitrogen). It was found that lipolysis in herby cheeses increased with increasing herb addition, and the increase in lipolysis degree was significant (P < 0.05) in cheese D. Water-soluble N, TCA-soluble N, and PTA-soluble N as indicator of proteolysis degrees were affected significantly (P < 0.05) by increasing herb ratios.

Allium vegetables and their associated organosulfur constituents are extensively studied for their chemopreventive potential against cancer. This article overviews their anticarcinogenic and antigenotoxic properties. Epidemiological studies (mostly case-control studies) provide strong evidence that Allium vegetable consumption reduces the incidence of gastric and colon cancer while the association between Allium vegetable consumption and other cancers is less convincing. Furthermore, many experimental studies have demonstrated that organosulfur compounds and Allium extracts have inhibitory effects on carcinogenesis in animals. These inhibitory effects are supported by many diverse mechanisms, including inhibition of carcinogen formation, modulation of carcinogen metabolism, inhibition of mutagenesis and genotoxicity, inhibition of cell proliferation and increase of apoptosis, inhibition of angiogenesis, and immune system enhancement. Before such constituents or extracts can be used in chemopreventive trials, it is important to verify their lack of toxicity and to investigate further their precise mechanisms of action throughout the whole process of carcinogenesis.

One of the major mechanisms of protection against carcinogenesis, mutagenesis, and other forms of toxicity mediated by carcinogens is the induction of enzymes involved in their metabolism, particularly phase 2 enzymes such as glutathione S-transferases, UDP-glucuronosyl transferases, and quinone reductases. Animal studies indicate that induction of phase 2 enzymes is a sufficient condition for obtaining chemoprevention and can be achieved by administering any of a diverse array of naturally-occurring and synthetic chemopreventive agents. Alliaceous and cruciferous plants are rich in organosulfur compounds with inducer activity. Indeed, monitoring of enzyme induction has led to the recognition or isolation of novel, potent chemopreventive agents such as 1,2-dithiole-3-thiones, dithiins and the isothiocyanate sulforaphane. For example, oltipraz, a substituted 1,2-dithiole-3-thione originally developed as an antischistosomal agent, possesses chemopreventive activity against different classes of carcinogens targeting multiple organs. Mechanistic studies in rodent models for chemoprevention of aflatoxin B1 (AFB1)-induced hepatocarcinogenesis by oltipraz indicates that increased expression of phase 2 genes is of central importance, although inhibition of phase 1 activation of aflatoxin B1 can also contribute to protection. Exposure of rodents to 1,2-dithiole-3-thiones triggers nuclear accumulation of the transcription factor Nrf2 and its enhanced binding to the Antioxidant Response Element, leading to transcriptional activation of a score of genes involved in carcinogen detoxification and attenuation of oxidative stress. Nrf2-deficient mice fail to induce many of these genes in response to oltipraz and the impact of this genotype on the chemopreventive efficacy of dithiolethiones is currently under investigation. To test the hypothesis that enzyme induction is a useful strategy for chemoprevention in humans, three key elements are necessary: a candidate agent, an at-risk population and modulatable intermediate endpoints. Towards this end, a placebo-controlled, double blind clinical trial of oltipraz was conducted in residents of Qidong, P.R. China who are exposed to dietary aflatoxins and who are at high risk for the development of liver cancer. Oltipraz significantly enhanced excretion of a phase 2 product, aflatoxin-mercapturic acid, a derivative of the aflatoxin-glutathione conjugate, in the urine of study participants administered 125 mg oltipraz by mouth daily. Administration of 500 mg oltipraz once a week led to a significant reduction in the excretion of the primary oxidative metabolite of AFB1, aflatoxin M1, when measured shortly after drug administration. While this study highlighted the general feasibility of inducing phase 2 enzymes in humans, a longer term intervention is addressing whether protective alterations in aflatoxin metabolism can be sustained for extended periods of time in this high-risk population. Food-based approaches to chemoprotection, targeted both to the general population and high-risk individuals, offer many practical advantages compared to the use of pharmaceutical agents. Thus, identification and utilization of naturally-occurring organosulfur chemoprotectors including dithiins should be a high priority.

Sulfur compounds contributed to the health promotion in Allium species are produced via enzymic and thermal reactions. Potent antithrombotic agents which have been identified as allyl trisulfides, dithiins, and ajoene in garlic (A. sativum) and caucas (A. victorialis) are thermochemically transformed from allicin (allyl 2-propenethiosulfinate). The leaves and stems of Japanese domestic Allium plant, A. victorialis L. which is widely distributed in the northern part of Japan, under the name "Gyoja-ninniku" is a nutritious vegetable. The significant flavor compounds of caucas are methyl allyl disulfide (Chinese chive odor), diallyl disulfide (garlic-like odor), and dimethyl disulfide and methyl allyl trisulfide (pickles-like odor) among more than 85 peaks on the gas chromatogram. 2-Vinyl-4H-1,3-dithiin and 3,4-dihydro-3-vinyl-1,2-dithiin as platelet aggregation inhibitors were found eliminated in dichloromethane extract of caucas. The significant health promoting factors, allyl trisulfides and dithiins were relatively increased when caucas was cooked on a frying pan.

Ultrastructural analysis of garlic roots treated for 24 h with sodium selenate or sodium selenite at the concentrations 80, 160, 320 microM revealed the presence of selenium deposits in meristematic cells. They appeared as small and large granules or aggregates of electron-dense material. Many small granules were localised in plastids but some in mitochondria, endoplasmic reticulum as well as in Golgi apparatus, nucleus and cytoplasm. Sometimes the large granules were seen in cytoplasm but aggregates of electron-dense material only in vacuoles. It seems possible that these deposits represent a non-dissolved form of selenium, i.e. elemental selenium or its complexes with other ions.

The nuclei were isolated from the root meristematic cells of Allium cepa and the nuclear matrices were prepared. A 135 kD polypeptide, which is equivalent to Sc II in molecular weight, was revealed in the nuclei by SDS-PAGE and was then demonstrated to be an Sc II-like protein by Western blot with an anti-chicken Sc II antiserum. Neither the 135 kD polypeptide nor the positive labelling of the anti-Sc II antiserum was found in the nuclear matrices. The immuno-fluorescence tests showed that the nuclei labelled with the anti-Sc II antiserum emanated strong, specific fluorescence, while the fluorescence of the nuclear matrices was too weak to be detected. The results of immunoelectron microscopy indicated that a large number of the gold particles were concentrated in the condensed chromatin of the nuclei, but very few gold particles were distributed in cytoplasm and nucleoplasm. These results strongly suggested that an Sc II like protein is a component of the nuclei of A. cepa and is mainly located in the condensed chromatin regions, but the nuclear matrices contain no or very little amount of that protein. By means of immunofluorescence and immunoelectron microscopy, the chromosomes and chromosomal scaffolds of A. cepa labelled with the anti-chicken Sc II antiserum were observed to send off specific fluorescence and have many gold particles representing the presence of the Sc II-like protein distributed among them. The significance of the Sc II-like protein as a novel component in the nuclei, chromosomes and chromosome scaffolds of higher plants is discussed.

Four steroidal glycosides including deltoside and nolinofuroside D and two novel saponins were isolated from underground parts of Allium nutans L. On the basis of the spectral (LSIMS and NMR) analysis, the structures of the new compounds were established as 25R Delta(5)-spirostan 3beta-ol-3-O-¿alpha-L-rhamnopyranosyl(1-->2)-[beta-D-glucopyranosyl(1 -->4)]-O-beta-D-galactopyranoside¿ and 25R Delta(5)-spirostan 1beta, 3beta-diol 1-O-beta-D-galactopyranoside. On the basis of the extraction efficiency, the concentration of saponins was established to be about 4% of dry matter, which makes this species a good source of steroidal saponins for commercial use.

The study of mechanisms by which plants tolerate lead requires ultrastructural observations of lead distribution in cells. However, the conventional technique used in electron microscopy brings up the problem of lead translocation from tissues during chemical processing. If most of the lead is washed out of tissues, then the method is not suitable for this type of study; if, however, it remains in the tissues, the method can be used. The amount of lead washed out of Allium cepa root tips during successive stages of fixing and dehydrating was determined in this study. Allium cepa plants were treated with Pb(NO3)2 in hydroponic cultures. The conventional fixing (GA, OsO4) and dehydration (alcohol + propylene oxide or acetone) methods used in the preparation of tissues for electron microscopy were then applied to root tips. The lead content in tissues and in reagents was analysed in the successive stages of the procedure. It was shown that 96.2% of the lead taken up was retained in the tissues and was not washed out during fixing and dehydrating. Of the 3.8% of the lead lost in the chemical procedure, about half was washed out during fixing in osmium tetroxide. This reagent is thus the least suitable for this type of study. Our study showed that the conventional electron microscopy preparative technique is appropriate for studying the distribution of lead deposits in A. cepa root cells, owing to the way in which lead is compartmentalized/sequestered in plant cells.

An investigation of the extracts from bulbs of Allium porrum L. has led to the isolation of four spirostanol saponins. Two of them are new compounds and have been identified as: (25R)-5 alpha-spirostan-3 beta, 6 beta-diol 3-O-{O-beta-D-glucopyranosyl-(1-->2)-O-[beta-D-xylopyranosyl-(1-->3)]-O- beta -D-glucopyranosyl-(1-->4)-beta-D-galactopyranoside} (3) and (25R)-5 alpha-spirostan-3 beta,6 beta-diol 3-O-{O-beta-D-glucopyranosyl-(1-->3)-O-beta-D-glucopyranosyl-(1-->2)-O- [beta-D-xylopyranosyl-(1-->3)]-O-beta-D-glucopyranosyl-(1-->4)-beta-D- galactopyranoside} (4). The isolated compounds were evaluated for their antifungal activity.

Two new spirostanol saponins, tuberosides D and E, have been isolated from the seeds of Allium tuberosum. On the basis of spectral data and chemical reactions, their structures were established as (25S)-5alpha-spirostane-2alpha,3beta-diol 3-O-alpha-L-rhamnopyranosyl-(1-->2)-O-[alpha-L-rhamnopyranosyl-(1-->4 )]-O-beta-D-glucopyranoside and (25S)-5alpha-spirostan-2alpha, 3beta-diol 3-O-beta-D-glucopyranosyl-(1-->2)-O-[alpha-L-rhamnopyranosyl-(1-->4)] -O-beta-D-glucopyranoside, respectively.

Antioxidants are important species which possess the ability to protect the body from damage caused by free radical-induced oxidative stress. There is currently much interest in the antioxidant role of fruit, vegetables, wines and teas. In this study the antioxidant activity of leaf, bulb and root of Allium nutants L. was investigated. Biochemical parameters were also determined: activities of antioxidant enzymes (superoxide dismutase, catalase, peroxidase, glutathione peroxidase), quantities of malonyldialdehyde, superoxide and hydroxyl radicals and reduced glutathione and contents of total flavonoids, chlorophylls a and b carotenoids, vitamin C and soluble proteins. Our results indicated that Allium nutants L. exhibits antioxidant ability in all investigated plant organs. The highest antioxidant ability was observed in the leaves where all investigated antioxidant enzymes were active and quantities of malonyldialdehyde and OH. low. Reduced glutathione, pigments and carotenoids present in the leaves contribute to the high antioxidant activity. ESR investigation conducted with Allium nutans L. phosphate buffer (pH 7) extract showed that the signal DMPO-OH spin adducts in the presence of Allium nutans L. extract was reduced by 78.48%.

Chemical examination of the bulbs of Allium karataviense led to the isolation of five new spirostanol saponins (7-11) and a new furostanol saponin (12), together with a known steroidal sapogenin (1) and five known saponins (2-6). The structures of the new saponins were determined by detailed analysis of their spectral data, including two-dimensional NMR spectroscopy. The steroidal saponins produced by A. karataviense, except for 5 and 6, were found to be based upon (25R)-5 alpha-spirostane-2 alpha,3 beta,5,6 beta-tetrol (alliogenin) and contain a beta-D-glucopyranosyl moiety with the formation of an O-glycoside linkage to C-2 of the polyhydroxylated steroidal skeleton as the common structural feature. The isolated compounds were evaluated for cytostatic activity against human promyelocytic leukemia HL-60 cells.

Welsh onion, a member of the genus Allium, has been consumed for prevention of cardiovascular disorders. However, its underlying mechanisms are still unclear. We investigated whether Welsh onion extracts (green or white portion, raw or boiled) can alter vascular responses in vitro in the thoracic aortae of Sprague-Dawley rats. The possible roles of endothelium-derived factors in the Welsh onion extract-induced vascular responses were examined by applying various inhibitors, such as Nomega-nitro-L-arginine (10(-4) M), tetraethylammonium (10(-3) M), and SQ29548 (10(-5) M). Our results showed that Welsh onion extracts caused vasodilation on precontracted vessel rings. These effects were most pronounced in vessel rings treated with raw green-leaf extract (RG). Low doses of RG induced vasorelaxation, which was mediated by endothelium-derived nitric oxide. High doses of RG induced endothelium-independent vasorelaxation. On the other hand, the boiled Welsh onion extract also stimulated the release of an endothelium-derived contracting factor, which might be thromboxane A2. We conclude that Welsh onion extract can modulate vascular tone in both endothelium-dependent and endothelium-independent manners.

Welsh onion ethanol extracts were tested for their inhibitory activity against the growth and aflatoxin production of Aspergillus flavus and A. parasiticus. The survival of spores of A. flavus and A. parasiticus depended on both the extract concentration and the exposure time of the spores to the Welsh onion extracts. The mycelial growth of two tested fungi cultured on yeast extract-sucrose broth was completely inhibited in the presence of the Welsh onion ethanol extract at a concentration of 10 mg/ml during 30 days of incubation at 25 degrees C. The extracts added to the cultures also inhibited aflatoxin production at a concentration of 10 mg/ml or permitted only a small amount of aflatoxin production with extract concentration of 5 mg/ml after 2 weeks of incubation. Welsh onion ethanol extracts showed more pronounced inhibitory effects against the two tested aflatoxin-producing fungi than did the same added levels of the preservatives sorbate and propionate at pH values near 6.5.

Two nonvolatile flavor precursors occurring in Allium vegetables, S-propyl-L-cysteine and its sulfoxide, were heated in closed model systems at different temperatures (from 80 to 200 degrees C) in the presence of variable amounts of water (0-98%) for 1-60 min. It seems to be indisputable that thermally generated breakdown products of both S-propyl-L-cysteine and particularly S-propyl-L-cysteine sulfoxide can significantly participate in the aroma formation of culinary processed Alliumvegetables. Dipropyl disulfide, dipropyl trisulfide, propylthiol, and dipropyl thiosulfonate were identified as the predominant volatile compounds generated by thermal degradation of S-propylcysteine sulfoxide. Dipropyl disulfide and 2-(propylthio)ethylamine were the major breakdown products formed from S-propylcysteine. Substantial amounts of various alkyl- and alkylthio-substituted pyridines were also generated from both S-propylcysteine and its sulfoxide.

Steroid glicoside which structure was elucidated by using mass-spectroscopic and NMR techniques, has been isolated using column chromatography on reverse-phase silicagel (C-18) from underground parts of Allium nutans. This compounds for the first time was isolated from the plants of genus Allium.

In this study we have investigated the effects of Petiveria alliacea on the hematopoietic response of mice infected with Listeria monocytogenes. Our results demonstrate a protective effect of the crude extract of P. alliacea since the survival of the treated/infected was higher than that in the infected group. Moreover, the number of granulocyte/macrophage colonies (CFU-GM) and the serum colony stimulating activity levels were increased in the treated/infected mice in relation to the infected group. These results suggest an immunomodulation of Petiveria alliacea extract on hematopoiesis, which may be responsible, at least in part, for the increased resistance of mice to Listeria monocytogenes infection.

Phytochemical analysis of the fresh bulbs of Allium jesdianum yielded four steroidal glycosides, (22S)-cholest-5-ene-1beta,3beta, 16beta,22-tetrol 1,16-di-O-beta-D-glucopyranoside (1), (22S)-cholest-5-ene-1beta,3beta,16beta,22-tetrol 1-O-alpha-L-rhamnopyranosyl 16-O-beta-D-glucopyranoside (2), (25R)-5alpha-spirostane-2alpha,3beta-diol 3-O-[O-beta-D-glucopyranosyl-(1-->2)-O-[beta-D-xylopyranosyl-(1-->3)] -O-beta-D-glucopyranosyl-(1-->4)-beta-D-galactopyranoside] (F-gitonin) (3), and (25R)-5alpha-spirostane-2alpha,3beta, 6alpha-triol 3-O-[O-beta-D-glucopyranosyl-(1-->2)-O-[beta-D-xylopyranosyl-(1-->3)] -O-beta-D-glucopyranosyl-(1-->4)-beta-D-galactopyranoside] (4). Compound 2 is a new natural product, and 4 is a new spirostanol saponin. Compound 3 was found to exhibit cytostatic and cytotoxic activities against several malignant tumor cells.

The naturally occurring organosulfur compounds (OSCs) diallyl sulfide (DAS), diallyl disulfide (DADS), dipropyl sulfide (DPS), and dipropyl disulfide (DPDS) were studied with respect to their effects on hepatic, intestinal, renal, and pulmonary phase II drug metabolizing enzymes, i.e., glutathione S-transferase (GST), microsomal epoxide hydrolase (mEH), quinone reductase (QR), and UDP-glucuronosyltransferase (UGT). OSCs were administered po to male SPF Wistar rats. In addition to assays of total enzyme activity, the ability of OSCs to modify the levels of mEH and rGSTA1/A2, A3/A5, M1, M2, and P1 was assessed by Western blotting. Remarkably, DADS significantly increased all Phase II enzyme activities, except the pulmonary mEH. It was noteworthy that only DADS induced QR activity. DAS, DPS, and DPDS induced mEH, GST, and UGT activities in the liver. Interestingly, DAS, DPS, and DPDS significantly decreased renal GST activity. In the same manner, DAS, DPS, and DPDS decreased rGSTA1/A2 and A3/A5 levels in the kidney. Conversely, all OSCs were able to induce GST of alpha and mu classes in the liver. In the intestine, DADS and DAS increased rGSTA1/A2, M2, and P1, while rGSTA3/A5 and M2 were only increased by DADS. In addition, DADS induced rGSTP1 dramatically in the four tissues analyzed. DADS also increased the mEH levels in the liver, intestine, and kidney, while DAS and DPS moderately induced mEH level in the liver. This study brings additional insights into the effects of OSCs on Phase II enzymes and suggests that DADS could be a promising chemopreventive agent considering its pleiotropic capacity of induction., (Copyright 1999 Academic Press.)

Supercritical fluid (SF) extracts of homogenized ramp (Allium tricoccum Ait.) were separated and characterized with liquid chromatography coupled with atmospheric pressure chemical ionization mass spectrometric identification. The profiles of SF extracts of aqueous homogenates of ramp bulbs from three different seasons and growing regions revealed that the thiosulfinates were major components. In addition, some of the cepaenes (alpha-sulfinyldisulfides) found in extracts of onion juice, as well as allyl containing cepaenes (2-propenyl l-(2-propenylsulfinyl)propyl disulfide), are present in the ramp extracts. The amount of allicin in ramp bulb homogenates ranged from approximately 10% to 50% of that found in extracts of aqueous garlic homogenates. The greater amount of the methyl 1-propenyl thiosulfinates in the ramp extracts relative to that found in the garlic extracts correlates with the flavor characteristics of ramp bulbs.

Applying mice test on cancer model of S180 and Lewis cancer by using method clystered stomach(oral), observs the Anti-tumor function. Experiments showed that Allium sativum can inhibit tumor growth and Lengthen lift duration of mice, the rate of inhibiting tumor was 74.35% and life lengthening rate were 42.4%, with control grou comparison. There was profund difference between them. Besides, we discoved Allium sativum can raise immune function of mice.

Six compounds were isolated from the anticoagulation and anticancer fractions of the bulbs of Allium chinense G. Don. On the basis of chemical evidence and spectral analysis (IR, EI-MS, 1HNMR, 13CNMR, 1H-1H COSY, HMBC, HMQC and NOESY), their structures were established as (25R, S)-5 alpha-spirostane-3 beta-ol 3-O-(beta-D-glucopyranosyl-(1-->2)-[beta-D-glucopyranosyl-(1-->3)]-beta-D- glucopyranosyl-(1-->4)-beta-D-galactopyranoside) (1), (25R, S)-5 alpha-spirostane-3 beta-ol 3-O-(beta-D-glucopyranosyl (1-->2)-[beta-D-glucopyranosyl-(1-->3)](6-acetyl-beta-D-glucopyranosyl)- (1-->4)-beta-D-galactopyranoside) (2), (25R, S)-5 alpha-spirostane-2 alpha, 3 beta-diol 3-O-(beta-D-glucopyranosyl-(1-->2)-O-beta-D-glucopyranosyl-(1-->4)-beta-D- galactopyranoside) (3), (25S)-24-O-beta-D-glucopyranosyl-3 beta, 24 beta-dihydroxy-5 alpha-spirost-3-O-alpha-arabinopyranosyl-(1-->6)-beta-D-glucopyranoside (4), chinenoside II (5) and 2,3,4,9-tetrahydro-1-methyl-1H-pyrido [3,4-b] indole-3-carboxylic acid (6). 4 is a new steroidal saponin, named chinenoside VI. Compounds 1 to 3 are three pairs of steroidal saponin epimers. Among them, the 25S epimer of 2 is first reported, the 25R epimer of 2 and compound 6 were isolated from this title plant for the first time. The relative configuration of compound 6 was firstly determined by NOESY spectrum, and signals of C, H were assigned definitely.

The presence of actin in eukaryotic nuclei and chromosomes, and especially in higher plant nuclei and chromosomes, has not been well established. We detected actin in meristematic cells of Allium cepa with indirect immunofluorescence technique and observed bright fluorescence in the intact nuclei and chromosomes, indicating that actin is present in the nuclei and chromosomes of the higher plant. We labeled sections of the meristematic cells of A. cepa with immunogold technique, gold particles were found over the whole nuclei and a number of gold particles were concentrated in condensed chromatin and nucleoli, confirming the results of the immunofluoresence observations. We treated the nuclei and chromosomes of A. cepa with DNase I and 2M NaCl and obtained DNA- and histone-depleted nuclei and chromosomes. Indirect immunofluorescence tests showed that the DNA- and histone-depleted nuclei and chromosomes reacted positively with the anti-actin antibodies. These results demonstrate that actin exists not only in intact nuclei and chromosomes, but also in DNA- and histone-depleted nuclei and chromosomes of the plant. In addition, our immuno-fluorescence tests indicate that tropomyosin is present in the nuclei and chromosomes of A. cepa.

Effective constituents from bulb of Allium stativum were extracted by supercritical-CO2 fluid. These constituents were analyzed by GC-MS. The results showed that oils from SFE-CO2 contained 12 components, two of them were first obtained from the plant.

Cruciferae plants, banana and coriander each showed antibacterial activity. The highest activity among the food-stuffs tested was found in the stems of wasabi. An ethereal extract from wasabi stems had potent antibacterial activity and we isolated the active compound from the extract. Instrumental analysis identified the compound as 6-methylsulfinylhexyl isothiocyanate. Some homologues of 6-methylsulfinylhexyl isothiocyanate were also active against Escherichia coli and Staphylococcus aureus.

Lectins were isolated from roots and leaves of ramsons and compared to the previously described bulb lectins. Biochemical analyses indicated that the root lectins AUAIr and AUAIIr are identical to the bulb lectins AUAI and AUAII, whereas the leaf lectin AUAL has no counterpart in the bulbs. cDNA cloning confirmed that the leaf lectin differs from the bulb lectins. Northern blot analysis further indicated that the leaf lectin is tissue-specifically expressed. Sequence comparisons revealed that the ramsons leaf lectin differs considerably from the leaf lectins of garlic, leek, onion and shallot.

Four new sapogenins, porrigenins A (2a) and B (3a), identified as (25R)-5 alpha-spirostan-2 beta,3 beta,6 beta-triol and (25R)-2-oxo-5 alpha-spirostan-3 beta,6 beta-diol, respectively, and neoporrigenins A (2b) and B (3b) were also isolated from Allium porrum. In addition, the known agigenin (1a) and its 25S epimer, neoagigenin (1b), were also identified. Their structure elucidation was provided by comprehensive spectroscopic analyses. Compounds 1a, 2a, and 3a exhibited cytotoxicity and high antiproliferative activity on four different tumor cell lines in vitro.

In this communication both matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) and high-performance anion-exchange chromatography (HPAEC) have been applied to analyze fructans from higher plants. Size distribution of a commercially available fructan preparation from Dahlia variabilis L. was determined by MALDI-MS. Molecular masses ranged from 2,000 up to 6,000 Da with a peak value of distribution at 2,635 Da. Essentially the same pattern was obtained using HPAEC. Low-molecular-weight fructans from onion bulbs (Allium cepa L.) were studied in more detail. Tissue extracts were analyzed by MALDI-MS without any analyte purification. Mass-spectra of both proteins and oligosaccharides were obtained. For identification, metastable ion scanning was performed. Neither deproteinization nor deionization of the samples affected the oligosaccharide pattern. Using HPAEC, a more complex oligosaccharide pattern was obtained because isomeric glycans were differentiated. However, the overall size distribution was similar to that obtained by MALDI-MS. In further experiments epidermal or parenchyma cell layers of the onion bulb were placed into matrix solution and were then subjected to MALDI-MS and metastable ion scanning as well. By taking this approach, analyte desorption was achieved immediately from plant tissue. Oligosaccharide mass spectra were essentially the same as those of the extracts. To our knowledge, this is the first time that MALDI-MS has been applied as a microprobe to plant tissue. Finally MALDI-MS analysis was performed using single-cell extracts from onion tissues without any purification of the analyte.

An investigation of the extracts from Allium neapolitanum has led to the isolation of 13 flavonoid glycosides, based on kaempferol, quercetin and isorhamnetin. Four of them are new compounds and have been identified as: kaempferol 3-O-[[2-O-alpha-L-rhamnopyranosyl-4-O-beta-D-glucopyranosyl]-beta-D- glucopyranoside]], isorhamnetin 3-O-[[2-O-alpha-L-rhamnopyranosyl-6-O-beta- D-glucopyranosyl]-beta-D-glucopyranoside], isorhamnetin 3-O-[[2-O-alpha-L-rhamnopyranosyl-6-O-beta-D-glycopyranosyl] beta-D-glucopyranoside]-7-O-beta-D-glucopyranoside and isorhamnetin 3-O-[[2-O-alpha-L-rhamnopyranosyl-6-O-beta-D-gentiobiosyl]- beta-D-glucopyranoside]]. The isolated compounds were evaluated for their anti-aggregation human platelet activity.

Analysis of nectar from leek (Allium porrum) flowers by SDS-PAGE revealed the presence of two major polypeptide bands of 50 kDa and 13 kDa, respectively. Using a combination of agglutination tests, enzyme assays and N-terminal sequencing, the polypeptides have been identified as subunits of alliin lyase (alliinase, EC 4.4.1.4) and mannose-binding lectin, respectively. The latter protein is particularly abundant since it represents about 75% of the total nectar protein. Honey produced by bees foraging on flowering leek plants still contains biologically active lectin and alliinase. However, the levels of both proteins are strongly reduced as compared to those in the original nectar. It is evident, therefore, that the lectin as well as the alliinase are inactivated/degraded during the conversion of nectar into honey.

Onion and garlic contain many sulfur containing active principles mainly in the form of cysteine derivatives, viz. S-alkyl cysteine sulfoxides which decompose into a variety of thiosulfinates and polysulfides by the action of an enzyme allinase on extraction. Decomposed products are volatile and present in the oils of onion and garlic. They possess antidiabetic, antibiotic, hypocholesterolaemic, fibrinolytic and various other biological actions. In addition to free sulfoxides in alliums, there are nonvolatile sulfur-containing peptides and proteins which possess various activities and thus make these vegetables as an important source of therapeutic agents. As allyl and related sulfoxides are inhibiting thiol group enzymes, alliums are to be used only in limited quantities.

The analysis of isolated nucleolar matrices from onion cells by light and electron microscopy, 2-D separation of proteins, and confocal microscopy has confirmed the existence of an organized nucleolar matrix with a complex protein composition to which are attached the insoluble processing complexes. In the present work, we present evidence from immunoblotting, immunofluorescence, immunogold labeling, and preferential cytochemical staining with bismuth salts that an insoluble fraction of the multifunctional protein nucleolin, is a component of the onion nucleolar matrix, and analyse its ultrastructural distribution in the described domains of the matrix.

Quercetin is a dietary antioxidant that prevents oxidation of low-density lipoproteins in vitro. Intake of quercetin was inversely associated with coronary heart disease mortality in elderly Dutch men. However, the extent of absorption of quercetin in humans is unclear. The aim of this study was to quantify absorption of various forms of quercetin. Nine healthy ileostomy subjects were studied, to avoid losses caused by colonic bacteria. They followed a quercetin-free diet for 12 d; on days 4, 8, and 12 they received a supplement of fried onions at breakfast (rich in quercetin glucosides) equivalent to 89 mg aglycone, pure quercetin rutinoside (the major quercetin compound in tea) equivalent to 100 mg aglycone, or 100 mg pure quercetin aglycone, in random order. Subsequently, participants collected ileostomy effluent and urine for 13 h. In vitro incubations of quercetin or its glycosides with gastrointestinal fluids showed minimal degradation. Absorption of quercetin, defined as oral intake minus ileostomy excretion and corrected for 14% degradation within the ileostomy bag, was 52 +/- 15% for quercetin glucosides from onions, 17 +/- 15% for quercetin rutinoside, and 24 +/- 9% for quercetin aglycone. Mean excretion of quercetin or its conjugates in urine was 0.5% of the amount absorbed; quercetin excretion in urine was negatively correlated with excretion in ileostomy effluent (r = -0.78, n = 27). We conclude that humans absorb appreciable amounts of quercetin and that absorption is enhanced by conjugation with glucose.

The saponin fraction prepared from the methanolic extract of Allium chinense bulbs exhibited inhibitory activities on cyclic AMP phosphodiesterase (cAMP PDE) (43.5%) and Na+/K+ ATPase (59.3%) at a sample concentration of 100 micrograms ml-1, respectively. Attempted purification of the active fraction through column chromatography on silica gel and ODS silica gel resulted in the isolation of six steroidal saponins, one of which appeared to be a new compound and one to be the first isolation from a natural source. (25R,S)-5 alpha-Spirostan-3 beta-ol tetrasaccharide showed inhibitory activities on both cAMP PDE and Na+/K+ ATPase, while (25R)-3 beta-hydroxy-5 alpha-spirostan-6-one di- and tri-saccharides inhibited only cAMP PDE.