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1.
High-performance liquid chromatography-diode array detector (HPLC-DAD) coupled with electron spray mass spectrometry (ESI-MS-MS) was used to determine the flavonol profile in southern Italian red onions (Allium cepa L.). This on-line technique allowed the identification of seven flavonols in southern Italian red onion, quercetin 4'-glucoside and quercetin 3,4'-diglucoside being the most abundant components. Five minor flavonols have been recognized, offering a characteristic profile of such compounds in red onions under study. Quercetin 3-glucoside, quercetin 7,4'-diglucoside, quercetin 3,7,4'-triglucoside, and isorhamnetin 4'-glucoside have been previously reported as minor flavonoid components in Allium cepa, while isorhamnetin 3,4'-diglucoside was previously found in Allium ascalonicum. Traces of isorhamnetin 3-glucoside and free quercetin were also detected.  相似文献   

2.
Interspecific hybridization between wild and cultivated species of the genus Allium has been performed to generate plant material possessing biochemical properties of both parental plants. These cross-breeding experiments should lead to Allium plants with higher amounts of valuable constituents. The chemical characterization of interspecific hybrids between A. cepa and A. kermesinum is described on the basis of their sulfur-containing constituents and secondary metabolites. In addition, the hybrid character has been proven by random amplified polymorphic DNA (RAPD) analysis of the progenies obtained from the crosses. It has been shown that the distribution of the cysteine sulfoxides as well as the volatile secondary metabolites in the hybrids is not uniform. The profiles are mainly determined by the paternal wild species A. kermesinum. It has been ascertained that the gas chromatography profiles of the hybrids show increasing amounts of unsymmetrical substituted oligosulfides, which are known to be physiologically active substances. On the basis of statistical calculations, three different types of hybrids can be separated. The chemical analysis of cysteine sulfoxides and volatile sulfur-containing substances is shown to be a useful tool for breeding purposes as it allows an effective selection with regard to optimal distribution and amount of valuable constituents.  相似文献   

3.
For taxonomic purposes and because many wild relatives of Allium crops are endangered in their native habitat (Sancir et al., 1989), a collection of Allium species was built up in the IPK at Gatersleben. At present it consists of more than 3000 accessions representing about 330 species. In this context it was necessary to study the seed germination behaviour and dormancy of certain wild Allium species. Therefore, seeds of 91 wild and three cultivated Allium species were tested at germination temperatures of 5°, 11°, 16° and 26°C. The purpose of this study was to develop routine germination tests for the genebank work with wild alliums.  相似文献   

4.
Three new sulfur-containing compounds were identified in Allium L. species belonging to the subgenus Melanocrommyum as the first examples of sulfur-containing pyrrole derivatives in nature. Some of these species are traditionally used in Southwest and Central Asia as vegetables and herbal drugs. A hypothetical biogenetic scheme is proposed in which L-(+)- S-(3-pyrrolyl)cysteine sulfoxide is enzymically degraded. The resulting 2-lactyl-3'-pyrrolyl sulfoxide is condensed readily to the red pigment 3,3'-dithio-2,2'-dipyrrole. All compounds are chemically unstable, rendering the analysis extremely difficult. Correlation NMR in combination with diffusion NMR allowed the identification of these low molecular weight compounds. For the first time, the compounds involved in the coloring process of Allium plant material have been identified from native plant material.  相似文献   

5.
Genetic Resources and Crop Evolution - The genus Allium is one of the largest monocotyledon genera having 1000 designated species with commercial and economic significance. Allium cepa L. (onion)...  相似文献   

6.
A phytochemical analysis of the polar extract from the red bulbs of Allium cepa L. var. Tropea, typical of Calabria, a southern region of Italy, was performed extensively for the first time, leading to the isolation of four new furostanol saponins, named tropeoside A1/A2 (1a/1b) and tropeoside B1/B2 (3a/3b), along with the respective 22-O-methyl derivatives (2a/2b and 4a/4b), almost certainly extraction artifacts. High concentrations of ascalonicoside A1/A2 (5a/5b) and ascalonicoside B (6), previously isolated from Allium ascalonicum Hort., were also found. This is the first report of furostanol saponins in this A. cepa variety. The chemical structures of the new compounds were established through a combination of extensive nuclear magnetic resonance, mass spectrometry and chemical analyses. High concentrations of quercetin, quercetin 4(I)-glucoside, taxifolin, taxifolin 7-glucoside, and phenylalanine were also isolated. The new saponins were found to possess antispasmodic activity in the guinea pig isolated ileum; such an effect might contribute to explaining the traditional use of onion in the treatment of disturbances of the gastrointestinal tract.  相似文献   

7.
Marasmin, which is especially known from the two South African species Tulbaghia alliacea and Tulbaghia violacea , but was also described for the garlic mushroom Marasmius alliaceus , is the precursor of the thiosulfinate marasmicin. Marasmicin has attracted considerable attention because of its antifungal and tuberculostatic activities. However, many Allium species of the subgenus Melanocrommyum, especially Allium suworowii , are also very rich in marasmin. A. suworowii revealed concentrations of marasmin up to 1.6%, related to the fresh weight of bulbs, and up to 3.0%, related to air-dried fruiting bodies, of the corresponding γ-glutamylmarsmin was found in M. alliaceus. Both species show much higher amounts of marasmin as Tulbaghia and could be considered as natural sources for the isolation of this compound. Further promising Allium species with considerable amounts of marasmin besides other cysteine sulfoxides are Allium stipitatum and Allium altissimum . (R(S),R(C))-Marasmin is typical for the investigated species of the subgenus Melanocrommyum, whereas γ-glutamyl-(S(S),R(C))-marasmin is the only cysteine sulfoxide for the genus Marasmius known until now. Both cysteine sulfoxides were isolated and described as o-phthaldialdehyde (OPA) derivatives. Furthermore, the cysteine sulfoxides methiin, propiin, S-(2-pyrrolyl)-cysteine sulfoxide, eventually S-(2-pyridyl)-cysteine sulfoxide and S-(2-pyridyl)-L-cysteine N-oxide were found.  相似文献   

8.
The Sicilian wild tetraploid oat Avena insularis is a close relative of A. magna and A. murphyi and is more plausible than either of these two species as the immediate tetraploid ancestor of A. sterilis and the other hexaploid oats. This report presents the C-banding karyotype of A. insularis. As in A. magna and A. murphyi, the chromosomal complement can be divided into two groups, one predominantly heterochromatic and the other predominantly euchromatic. The heterochromatic chromosome group of A. insularis consists of three pairs of metacentric and four pairs of submetacentric chromosomes. The euchromatic chromosome group consists of one pair of metacentric, five pairs of submetacentric, and one pair of subtelocentric chromosomes.  相似文献   

9.
珠江三角洲几种主要蔬菜的镁硼钼适用量研究   总被引：1，自引：1，他引：0  
为获得珠江三角洲地区蔬菜中微量元素的合理用量,通过在2地进行3种蔬菜施镁、硼、钼的田间试验,研究三种元素不同配比对三种蔬菜的影响。结果显示:(1)不同品种的蔬菜对中微量元素的需求量不同;相同品种蔬菜在不同地点土壤上的施镁、硼、钼肥效应不同;相同蔬菜镁、硼、钼配施比单独使用的施用量可大幅度减少,尤其是硼和钼可减少50%。(2)在施氮磷钾基础上单独施用镁、硼、钼,菜心的Mg适施量约为13.350～15.750 kghm-2;B的适施量约为0.990～1.065 kghm-2;Mo的适施量为0.375～0.420 kg hm-2。蒜青的Mg适施量约为1.500 kg hm-2;B的适施量约为0.450 kg hm-2;Mo的适施量为0.240 kg hm-2。苦瓜的施硼适用量范围在1.050 kg hm-2左右。(3)在施氮磷钾基础上镁、硼、钼配合施用,菜心的Mg适施量约为12.000 kghm-2、B适施量约为0.450 kghm-2、Mo适施量约为0.240 kghm-2;苦瓜的Mg适施量约为12.000～18.000 kghm-2、B适施量约为0.450～1.800 kg hm-2、Mo适施量为0.120～0.240 kg hm-2;蒜青的B和Mo适用量分别为0.900 kg hm-2和0.210 kg hm-2、镁的施用量则应<1.350 kg hm-2。(4)镁和硼的施用量不仅受试验地土壤交换性镁和有效硼含量水平的影响,还与土壤pH值和蔬菜目标产量有关。  相似文献   

10.
A quantitative method is described for the determination of allicin (2-propene-1-sulfinothioic acid S-2-propenyl ester) in garlic, using standard additions of alliin (l-(+)-S-allylcysteine sulfoxide) in conjunction with supercritical fluid extraction (SFE) and high performance liquid chromatography analysis with UV-vis absorbance detection. Optimum CO(2)-SFE conditions provided 96% recovery for allicin with precision of 3% (RSD) for repeat samples. The incorporation of an internal standard (allyl phenyl sulfone) in the SFE step resulted in a modest improvement in recovery (99%) and precision (2% RSD). Standard additions of alliin were converted to allicin in situ by endogenous alliinase (l-(+)-S-alk(en)ylcysteine sulfoxide lyase, EC 4.4.1.4). Complete conversion of the spiked alliin to allicin was achieved by making additions after homogenization-induced conversion of the naturally occurring cysteine sulfoxides to thiosulfinates had taken place, thus eliminating the likelihood of competing reactions. Concentration values for allicin determined in samples of fresh garlic (Allium sativum L. and Allium ampeloprasum) and commercially available garlic powders (Allium sativum L.) by standard addition of alliin were found in all cases to be in statistical agreement (95% confidence interval) with values determined using a secondary allicin standard (concentration determined using published extinction coefficients). This method provides a convenient alternative for assessing the amount of allicin present in fresh and powdered garlic, as alliin is a far more stable and commercially prevalent compound than allicin and is thus more amenable for use as a standard for routine analysis.  相似文献   

11.
Sulfur-containing compounds of ramson (Allium ursinum L.) are responsible for its traditional use in terms of culinary and medicinal purposes. Leaves and bulbs were investigated for their contents of cysteine sulfoxides (volatile precursors) as well as volatile compounds released from minced plant material. Plants were analyzed during the whole vegetation period, focused on the months from March to June. Additionally, within the dormancy period bulbs were analyzed again and alliinase activity was determined. The pattern of volatile compounds was analyzed both by SPME/GC-MS and by SDE/GC-MS. Compared to each other, SDE exhibited a wider spectrum of detectable volatile compounds. The quality and quantity of volatiles significantly depended on the time of harvest. The highest amounts of volatile precursors can be gained in March and April, shortly before flowering time (up to 0.4% of total cysteine sulfoxides). The main cysteine sulfoxides were alliin and isoalliin. It has been found that alliinase of A. ursinum exhibited properties similar to those of alliinase of garlic (Allium sativum L.), but differing in terms of substrate specificity.  相似文献   

12.
Chemotype analyses and random amplified polymorphic DNA (RAPD) genomic analyses have been applied to the characterization of Allium sativum variety from Voghiera (Ferrara, Italy), a typical Italian product actually demanding the Protected Designation of Origin (PDO). The garlic from Voghiera is characterized by peculiar morphological and composition characteristics. The proximate composition and atomic absorbance spectrometry elemental pattern of this garlic suggested as the chemical composition did not depend on the intrinsic pedologic soil features only, but it was probably connected to some peculiar genetic characters. Amplification of genomic DNA using random primers highlighted a good clustering differentiating of Voghiera Allium sativum from five commercial reference samples used in this study (Piacentino, Serena, France, China, and Adriano varieties), confirming the existence of intervarietal genetic difference. The intravarietal polymorphisms of Voghiera samples were low.  相似文献   

13.
A new species of oat, Avena insularis, is described. It was collected in southern Sicily where four populations were found on uncultivated clay soil. Morphologically, it is similar to the hexaploid wild oat A. sterilis, but can be distinguished by its smaller and more condensed panicle, less V-shaped dispersal unit and oblong disarticulation scar. Hybrids between A. insularis and the hexaploid cultivated oat A. sativa were obtained only when the latter was the seed parent in crosses. Chromosome pairing of the hybrids at meiosis was irregular with univalents and multivalents, but the mean number of chiasmata per cell was close to that of A. insularis. Furthermore, the hybrids were partially self-fertile. Thus, the newly discovered species seems closer to the hexaploid oats than any other tetraploid species, and is probably the tetraploid progenitor of hexaploid oats. Hybrids between A. insularis and A. magna were sterile because of irregular chromosome pairing at meiosis.  相似文献   

14.
The precursor of the orange-red pigment formed upon wounding the bulbs of Allium giganteum (Allium subg. Melanocrommyum) was isolated and shown to be S-(2-pyrrolyl)cysteine S-oxide. In addition, two other pyrrolylsulfinyl derivatives were found in an extract from the bulbs, namely, 3-(2-pyrrolylsulfinyl)lactic acid and S-(3-pyrrolyl)cysteine S-oxide. Contrary to a previous report, the latter compound was shown not to serve as the precursor of the pigment, being in fact only an artifact formed during isolation. The formation of pyrrolyl-containing compounds following disruption of A. giganteum bulbs was studied by a combination of LC-MS, LC-NMR and DART-MS. It was found that S-(2-pyrrolyl)cysteine S-oxide is cleaved by a C-S lyase (alliinase) to yield 2-pyrrolesulfenic acid. Two molecules of the latter compound give rise to highly reactive S-(2-pyrrolyl) 2-pyrrolethiosulfinate which in turn converts into red 2,2'-epidithio-3,3'-dipyrrole (dipyrrolo[2,3-d:2',3'-e]-1,2-dithiin). Several other pyrrolyl-containing compounds were detected in A. giganteum for the first time, including S-methyl 2-pyrrolethiosulfinate, S-(2-pyrrolyl) methanethiosulfinate, di(2-pyrrolyl) disulfide, and S-(2-pyrrolyl) 2-pyrrolethiosulfonate. It can be concluded that the formation of the orange-red pigment in Allium subg. Melanocrommyum species, despite sharing several analogous features, is of a different nature than the pink discoloration of onion (A. cepa).  相似文献   

15.
In this study we isolated crude thiosulfinates from Allium tuberosum L. using CH 2Cl 2 and then with silica gel column chromatography purified S-methyl methanthiosulfinate and S-methyl 2-propene-1-thiosulfinate from the crude thiosulfinates. Subsequently, in vitro cytotoxicities against human cancer cells and in vivo antitumor activities of the thiosulfinates were investigated. Their cytotoxicities were strong in human cancer cells, in the order of S-methyl 2-propene-1-thiosulfinate, crude thiosulfinates, and S-methyl methanthiosulfinate. When thiosulfinates were administered consecutively for 7 days at 10, 30, and 50 mg/kg ip, in mice, we found significant increases in the life spans of mice that had been inoculated with Sacorma-180 tumor cells. The crude thiosulfinates also induced apoptosis in MCF-7 cancer cells. These results suggest that thiosulfinates from Allium tuberosum L. inhibit the proliferation of cancer cells via apoptosis and have antitumor activities.  相似文献   

16.
A new unsaturated fatty acid monoglyceride (1), glycerol mono-(E)-8,11,12-trihydroxy-9-octadecenoate, was isolated from the seeds of Allium fistulosum L. along with five known compounds: tianshic acid (2), 4-(2-formyl-5-hydroxymethylpyrrol-1-yl) butyric acid (3), p-hydroxybenzoic acid (4), vanillic acid (5), and daucosterol (6). The structures of 1-3 were established by interpretation and full assignments of NMR spectroscopic data. Both 1 and 2 were found to inhibit the growth of Phytophtohora capsici on V8 media.  相似文献   

17.
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.  相似文献   

18.
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 相似文献   

19.
Three vegetative crops of sect. Cepa in genus Allium (Top onion, French grey shallot and viviparous triploid onion) of suspected hybridogenic origin were studied with genomic in situ hybridization (GISH) and random amplified polymorphic DNA (RAPD) markers. Related wild and cultivated species were included in the analysis in order to assess their contributions to the genomes of the investigated species. In A. × proliferum, the parental chromosomes derived from A. fistulosum and A. cepa were unequivocally identified by GISH, proving the hybrid status of this crop. The French grey shallot proved to belong to A. oschaninii according to the RAPD analysis and the GISH results, it is clearly separate from the normal shallots of A. cepa var. aggregatum. Thus the grey shallots are a new crop species and can be considered as an aggregatum form of the wild progenitor species A. oschaninii. The triploid viviparous onion comprises mostly A. cepa derived DNA in its genome. A non-cepa component could not be attributed to any of the sect. Cepa species included in this study and is most likely derived from one of the species of this section not yet identified by molecular means.  相似文献   

20.
针对现有根茎类作物收获机用于藠头收获时存在的果土分离不彻底、埋果率高、地形适应性差等问题，该研究研制了基于"杆筛式振动碎土+拨辊推送式多级分离"技术的自走式藠头收获机。对挖掘和果土分离过程中的物料状态和作业机理进行了分析，建立模型计算得到了挖掘装置的位置和深度、杆筛式振动装置的振幅和曲柄转速、拨辊的尺寸和位置等关键参数，基于可调式挖掘装置、杆筛式振动装置、拨辊推送式多级分离装置组成加工了藠头收获机样机。针对研究内容设计了田间挖掘试验和整机性能试验，对以上装置及整机的作业性能进行验证。田间试验表明：该机实际挖掘深度稳定，漏挖率、埋果率、总伤果率分别为0.31%、3.20%、5.87%，有效收获率为93.23%。整机结构及布局合理，性能稳定，能够满足当前丘陵山区条件下藠头机械化收获的需求。  相似文献   

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