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1.
The flavonoids present in passion fruit (Passiflora edulis) leaves were identified by a high-performance liquid chromatography-diode array detection-tandem mass spectrometry (HPLC-DAD-MS/MS) method. Sixteen apigenin or luteolin derivatives were characterized, which included four mono-C-glycosyl, eight O-glycosyl- C-glycosyl, and four O-glycosyl derivatives. With the exceptions of C-hexosyl luteolin and C-hexosyl apigenin, all the compounds exhibited a deoxyhexose moiety. Moreover, the uncommon C-deoxyhexosyl derivatives of luteolin and apigenin have been identified for first time in P. edulis by HPLC-DAD-MS/MS. The antioxidative capacity of passion fruit leaves was checked against DPPH radical and several reactive oxygen species (superoxide radical, hydroxyl radical, and hypochlorous acid), revealing it to be concentration-dependent, although a pro-oxidant effect was noticed for hydroxyl radical.  相似文献   

2.
Studies were conducted on the flavonoids (myricetin, quercetin, kaempferol, luteolin, and apigenin) contents of 62 edible tropical plants. The highest total flavonoids content was in onion leaves (1497.5 mg/kg quercetin, 391.0 mg/kg luteolin, and 832.0 mg/kg kaempferol), followed by Semambu leaves (2041.0 mg/kg), bird chili (1663.0 mg/kg), black tea (1491.0 mg/kg), papaya shoots (1264.0 mg/kg), and guava (1128.5 mg/kg). The major flavonoid in these plant extracts is quercetin, followed by myricetin and kaempferol. Luteolin could be detected only in broccoli (74.5 mg/kg dry weight), green chili (33.0 mg/kg), bird chili (1035.0 mg/kg), onion leaves (391.0 mg/kg), belimbi fruit (202.0 mg/kg), belimbi leaves (464.5 mg/kg), French bean (11.0 mg/kg), carrot (37.5 mg/kg), white radish (9.0 mg/kg), local celery (80.5 mg/kg), limau purut leaves (30.5 mg/kg), and dried asam gelugur (107.5 mg/kg). Apigenin was found only in Chinese cabbage (187.0 mg/kg), bell pepper (272.0 mg/kg), garlic (217.0 mg/kg), belimbi fruit (458.0 mg/kg), French peas (176.0 mg/kg), snake gourd (42.4 mg/kg), guava (579.0 mg/kg), wolfberry leaves (547.0 mg/kg), local celery (338.5 mg/kg), daun turi (39.5 mg/kg), and kadok (34.5 mg/kg). In vegetables, quercetin glycosides predominate, but glycosides of kaempferol, luteolin, and apigenin are also present. Fruits contain almost exclusively quercetin glycosides, whereas kaempferol and myricetin glycosides are found only in trace quantities.  相似文献   

3.
A standardized profiling method based on liquid chromatography with diode array and electrospray ionization/mass spectrometric detection (LC-DAD-ESI/MS) was used to analyze the phenolic compounds in the skins of 16 pears (Pyrus spp.). Thirty-four flavonoids and 19 hydroxycinnamates were identified. The main phenolic compounds (based on peak area) in all of the pear skins were arbutin and chlorogenic acid. The remaining phenolics varied widely in area and allowed the pears to be divided into four groups. Group 1, composed of four Asian pears (Asian, Asian brown, Korean, and Korean Shinko), contained only trace quantities of the remaining phenolics. Yali pear (group 2) contained significant amounts of dicaffeoylquinic acids. Fragrant pear (group 3) contained significant quantities of quercetin glycosides and lesser quantities of isorhamnetin glycosides and the glycosides of luteolin, apigenin, and chrysoeriol. The remaining 10 pears (group 4) (Bartlett, Beurre, Bosc, Comice, D'Anjou, Forelle, Peckham, Red, Red D'Anjou, and Seckel) contained significant quantities of isorhamnetin glycosides and their malonates and lesser quantities of quercetin glycosides. Red D'Anjou, D'Anjou, and Seckel pears also contained cyanidin 3-O-glucoside. Thirty-two phenolic compounds are reported in pear skins for the first time.  相似文献   

4.
It was assumed that gas-phase ligation of metal monocations by flavonoids might provide some insight on the intrinsic antioxidant activity of the latter. Thus, the ligation of Fe+ and Cu+ ions by apigenin (1), luteolin (2), kaempferol (3), quercetin (4), myricetin (5), and naringenin (6) was investigated in the gas phase in a Fourier transform mass spectrometer (FTMS). Both of the metal ions, which were produced by laser desorption ionization (LDI), bind consecutively to two neutral flavonoid molecules either with or without the simultaneous loss of some part (H, CO, H2O) of the latter. The flavonoids are present in the instrument at steady concentrations. The formation of flavonoid positive ions by charge exchange is also a common observation but is accompanied, in some cases, by a loss of H, CO, or H2O fragments. The reaction paths and observed fragmentations are presented. The results are supported by DFT B3LYP calculations that indicate a preference for metal ion attack at C-ring and not at the B-ring site considered to be mainly responsible for flavonoid antioxidant activity.  相似文献   

5.
Sweet peppers (Capsicum annuum L.) cv. Vergasa have been studied at four maturity stages (immature green, green, immature red, and red). The individual phenolics (hydroxycinnamic acids and flavonoids), vitamin C (ascorbic acid and dehydroascorbic acid), and individual carotenoids were characterized and quantified. Five hydroxycinnamic derivatives and 23 flavonoids were characterized and quantified from the pericarp of sweet pepper by high-performance liquid chromatography-diode array detection-electrospray ionization-mass spectrometry. Identification was carried out by their UV spectra, chromatographic comparisons with authentic markers, identification of hydrolysis products, and tandem mass spectrometry analysis. Hydroxycinnamic derivatives, O-glycosides of quercetin, luteolin, and chrysoeriol, and a large number of C-glycosyl flavones have been characterized. Some of these compounds were found for the first time in nature. Clear differences in the individual and total phenolic content were detected between the different maturity stages. Immature green pepper had a very high phenolic content while green, immature red, and red ripe peppers showed a 4-5-fold reduction. Ascorbic acid was the main form of vitamin C, and its content increased as the pepper reached maturity. The red ripe stage had a relevant impact on the carotenoids content. Thus, immature green peppers showed the highest content of polyphenols, while red ripe fruits had the highest content of vitamin C and provitamin A.  相似文献   

6.
A screening method using LC-DAD-ESI/MS was applied to the analysis of flavonoids in celery, Chinese celery, and celery seeds (Apium graveolens L. and varieties). Fifteen flavonoid glycosides were detected in the three celery materials. They were identified as luteolin 7-O-apiosylglucoside, luteolin 7-O-glucoside, apigenin 7-O-apiosylglucoside, chrysoeriol 7-O-apiosylglucoside, chrysoeriol 7-O-glucoside, and more than 10 malonyl derivatives of these glycosides. The identification of the malonyl derivatives was confirmed by their conversion into glycosides upon heating and by comparison of some of the malonates with malonates that had previously been identified in red bell pepper and parsley. The concentrations of the glycosides and the malonyl glycosides in the three materials were estimated by comparison to aglycone standards. This is the first report of the presence of these glycosylated flavonoid malonates in celery.  相似文献   

7.
Four cultivars (Bronowicka Ostra, Cyklon, Tornado, and Tajfun) of pepper fruit Capsicum annuum L. were studied for phenolics contents and antioxidant activity. Two fractions of phenolics, flavonoids (with phenolic acids) and capsaicinoids, were isolated from the pericarp of pepper fruit at two growth stages (green and red) and were studied for their antioxidant capacity. Both fractions from red fruits had higher activities than those from green fruits. A comparison of the capsaicinoid fraction with the flavonoid and phenolic acid fraction from red fruit with respect to their antioxidant activity gave similar results. Phenolic compounds were separated and quantified by LC and HPLC. Contents of nine compounds were determined in the flavonoid and phenolic acid fraction: trans-p-feruloyl-beta-d-glucopyranoside, trans-p-sinapoyl-beta-d-glucopyranoside, quercetin 3-O-alpha-l-rhamnopyranoside-7-O-beta-d-glucopyranoside, trans-p-ferulyl alcohol-4-O-[6-(2-methyl-3-hydroxypropionyl] glucopyranoside, luteolin 6-C-beta-d-glucopyranoside-8-C-alpha-l-arabinopyranoside, apigenin 6-C-beta-d-glucopyranoside-8-C-alpha-l-arabinopyranoside, lutoeolin 7-O-[2-(beta-d-apiofuranosyl)-beta-d-glucopyranoside], quercetin 3-O-alpha-l-rhamnopyranoside, and luteolin 7-O-[2-(beta-d-apiofuranosyl)-4-(beta-d-glucopyranosyl)-6-malonyl]-beta-d-glucopyranoside. The main compounds of this fraction isolated from red pepper were sinapoyl and feruloyl glycosides, and the main compound from green pepper was quercetin-3-O-l-rhamnoside. Capsaicin and dihydrocapsaicin were the main components of the capsaicinoid fraction. A high correlation was found between the content of these compounds and the antioxidant activity of both fractions. Their antioxidant activities were elucidated by heat-induced oxidation in the beta-carotene-linoleic acid system and the antiradical activity by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) decoloration test. The highest antioxidant activity in the beta-carotene-linoleic acid system was found for trans-p-sinapoyl-beta-d-glucopyranoside, which was lower than the activity of free sinapic acid. Quercetin 3-O-alpha-l-rhamnopyranoside had the highest antiradical activity in the DPPH system, which was comparable to the activity of quercetin. The activities of capsaicin and dihydrocapsaicin were similar to that of trans-p-feruloyl-beta-d-glucopyranoside in the DPPH model system.  相似文献   

8.
Liquid chromatography (LC) diode array detection (DAD) coupled to negative electrospray ionization (ESI) tandem mass spectrometry (MS/MS) was used for the rapid and sensitive identification of water-soluble phenolic compounds in fennel waste. The plant material was first extracted and then chromatographed on Sephadex LH-20 to afford seven fractions, each of them being subjected to LC-MS analysis. Identification of the compounds was carried out by interpretation of UV, MS, and MS/MS spectra. Forty-two phenolic substances were identified, 27 of which had not previously been reported in fennel, including hydroxycinnamic acid derivatives, flavonoid glycosides, and flavonoid aglycons.  相似文献   

9.
High-performance liquid chromatography combined with diode array and electrospray ionization mass spectrometric (MS) detection was used to study phenolic compounds in berries of black, green, red, and white currants (Ribes spp.). UV-visible spectrometry was a valuable tool for the identification of the class of the phenolic compound, whereas MS and MS-MS fragmentation data were useful for further structural characterization. Distinct similarities were found in the relative distribution of conjugated forms of phenolic compounds among the four currants. Phenolic acids were found mainly as hexose esters. Flavonol glycosides and anthocyanin pigments were mainly found as 3-O-rutinosides and second as 3-O-glucosides. However, cyanidin 3-O-sambubioside and quercetin hexoside-malonate were notable phenolic compounds in red currant. Flavonol hexoside-malonates were identified and quantified in the berries of currants for the first time.  相似文献   

10.
Horse chestnut extracts are widely used in pharmacy and cosmetic industries. The main active constituents are saponins of oleane type, but seeds of horse chestnut also contain flavonoids, being glycosides of quercetin and kaempferol. Their contribution to the overall activity of the extracts was not clear. In the present work, the main flavonoids from horse chestnut seeds were isolated and their structures established with spectral methods. Seven glycosides were isolated, out of which six ( 2, 3, 4, 7, 11, 13) were previously reported and one ( 9) was identified as a new tamarixetin 3- O- [beta- d-glucopyranosyl(1-->3)]- O-beta- d-xylopyranosyl-(1-->2)- O-beta- d-glucopyranoside. The structures of three additional compounds 1, 10, and 12, not previously reported, were deduced on the basis of their LC-ESI/MS/MS fragmentation characteristics. A new ultraperformance liquid chromatographic (UPLC) method has been developed for profiling and quantitation of horse chestnut flavonoids. The method allowed good separation over 4.5 min. Thirteen compounds could be identified in the profile, out of which di- and triglycoisdes of quercetin and kaempferol were the dominant forms and their acylated forms occurred in just trace amounts. The total concentration of flavonoids in the powdered horse chestnut seed was 0.88% of dry matter. The alcohol extract contained 3.46%, and after purification on C18 solid phase, this concentration increased to 9.40% of dry matter. The flavonoid profile and their content were also measured in the horse chestnut wastewater obtained as byproduct in industrial processing of horse chestnut seeds. The total flavonoid concentration in the powder obtained after evaporation of water was 2.58%, while after purification on solid phase, this increased to 11.23% dry matter. It was concluded that flavonoids are present in a horse chestnut extract in a relatively high amount and have the potential to contribute to the overall activity of these extracts. Industrial horse chestnut wastewater can be used to obtain quercetine and kaempferol glycosides for cosmetic, nutraceutical, and food supplement industries.  相似文献   

11.
Three antioxidative phenolic compounds, one serotonin derivative and two flavonoids, were isolated from an ethanol extract of Japanese barnyard millet (cv. Kurohie) grains by Sephadex LH-20 chromatography and preparative high-performance liquid chromatography. Their structures were established to be N-(p-coumaroyl)serotonin, luteolin, and tricin on the basis of spectrometric data from (1)H and (13)C and two-dimensional nuclear magnetic resonance techniques, fast atom bombardment mass spectrometry, and Fourier transform infrared spectrophotometry. N-(p-Coumaroyl)serotonin exhibited a strong antioxidant activity almost equivalent to that of butylated hydroxyanisole at the same concentration (w/v). Although the antioxidant activity of luteolin was lower than that of N-(p-coumaroyl)serotonin, it was nearly equal to that of quercetin, whereas the activity of tricin was lower than that of luteolin. All of them were newly isolated from Japanese barnyard millet grains.  相似文献   

12.
Iron chelation by the powerful antioxidant flavonoid quercetin   总被引：1，自引：0，他引：1  
Chelation of the bare and hydrated iron(II) cation by quercetin has been investigated at the DF/B3LYP level in the gas phase. Several complexed species arising from neutral and anionic forms of the ligand have been taken into account. Both 1:1 and 1:2 metal/flavonoid stoichiometries have been considered. Results indicate that among the potential sites of chelation present on quercetin, the oxygen atoms belonging to the 3-hydroxy and 4-oxo, and to the 5-hydroxy and 4-oxo groups, are the preferred ones. Time-dependent density functional theory (TDDFT) calculations, used to reproduce the electronic UV-vis spectra of isolated quercetin and its complexes with Fe2+, were also performed in methanol and dimethylsulfoxide.  相似文献   

13.
类黄酮对AM真菌孢子萌发和早期生长的影响   总被引：2，自引：0，他引：2  
李杨  赵斌 《土壤学报》2008,45(4):710-717
研究了离体培养条件下Quercetin、Naringin、Rutin、Umbelliferon、Biochanin A、Zeatin Riboside、Fla-vanon、Apigenin、Genistein、Formononetin等10种类黄酮化合物对Gigaspora margarita和Glomus geosporum孢子萌发及菌丝发育的影响。结果表明,Quercetin、Rutin促进Gi.margarita早期发育,在0.5~8.0μmol L-1浓度范围,Quercetin对菌丝生长、菌丝分枝及辅助细胞形成促进作用明显,菌丝长度、菌丝分枝数及辅助细胞群与对照组相比提高到2~3倍,其他类黄酮对Gi.margarita孢子早期生长无明显影响。在一定浓度条件下,Formononetin、Genistein和Naringin促进Gl.geosporum孢子萌发、菌丝生长及分枝,Apigenin、Flavanon和Naringin刺激次生孢子的形成,而Biochanin A仅促进其孢子萌发。类黄酮对AM真菌孢子发育种属差异性影响取决于类黄酮种类及其使用浓度,不同的类黄酮分别在AM真菌孢子萌发、菌丝生长及菌丝分化等不同发育事件中参与作用。研究类黄酮对AM真菌早期发育的影响机制有助于理解微生物与植物之间的相互作用。  相似文献   

14.
Liquid chromatography coupled with electrospray mass spectrometry (LC-ESI/MS) with positive and negative ion detection was used for the identification of flavonoids in Hakmeitau beans, a black seed cultivar of cowpea (Vigna sinensis). Gradient elution with water and acetonitrile, both containing 2% formic acid, was employed in chromatographic separation. The peaks were identified by comparison of the retention times and the UV-vis spectroscopic and mass spectrometric data with authentic standards and/or literature data. The identified flavonoids included six anthocyanins (cyanidin 3-O-galactoside, cyanidin 3-O-glucoside, delphinidin 3-O-glucoside, malvidin 3-O-glucoside, peonidin 3-O-glucoside, and petunidin 3-O-glucoside) and four flavonol/flavonol glycosides (kaempferol 3-O-glucoside, quercetin, quercetin 3-O-glucoside, and quercetin 3-O-6' '-acetylglucoside). The tentatively identified flavonoids included two anthocyanins (malvidin 3-O-acetylglucoside and peonidin 3-O-malonylglucoside) and three flavonol glycosides (myricetin-3-O-glucoside, quercetin 7-O-glucoside, and quercetin-3-O-diglucoside). These flavonoids are present in seed coats, and the contents of anthocyanins and flavonol glycosides were 20.7 and 2.0 mg/g, respectively.  相似文献   

15.
Phenolic compounds in Spanish virgin olive oils were characterized by HPLC. Simple phenols such as hydroxytyrosol, tyrosol, vanillic acid, p-coumaric acid, ferulic acid, and vanillin were found in most of the oils. The flavonoids apigenin and luteolin were also found in most of the oils. The dialdehydic form of elenolic acid linked to tyrosol and hydroxytyrosol was also detected, as were oleuropein and ligstroside aglycons. The structure of a new compound was elucidated by MS and NMR as being that of 4-(acetoxyethyl)-1,2-dihydroxybenzene. Changes of phenolic compounds in virgin olive oils with maturation of fruits were also studied. Hydroxytyrosol, tyrosol, and luteolin increased their concentration in oils with maturation of fruits. On the contrary, glucoside aglycons diminished their concentration with maturation. No clear tendency was observed for the rest of the phenolic compounds identified.  相似文献   

16.
The HPLC analyses of Australian unifloral Eucalyptus honeys have shown that the flavonoids myricetin (3,5,7,3',4', 5'-hexahydroxyflavone), tricetin (5,7,3',4',5'-pentahydroxyflavone), quercetin (3,5,7,3',4'-pentahydroxyflavone), luteolin (5,7,3', 4'-tetrahydroxyflavone), and kaempferol (3,5,7, 4'-tetrahydroxyflavone) are present in all samples. These compounds were previously suggested as floral markers of European Eucalyptus honeys. The present results confirm the use of flavonoid analysis as an objective method for the botanical origin determination of eucalyptus honey. Honeys from E. camaldulensis (river red gum honey) contain tricetin as the main flavonoid marker, whereas in honeys from E. pilligaensis (mallee honey), luteolin is the main flavonoid marker, suggesting that species-specific differences can be detected with this analysis. The main difference between the flavonoid profiles of Australian and European Eucalyptus honeys is that in the Australian honeys, the propolis-derived flavonoids (pinobanksin (3,5, 7-trihydroxyflavanone), pinocembrin (5,7-dihydroxyflavanone), and chrysin (5,7-dihydroxyflavone)) are seldom found and in much smaller amounts.  相似文献   

17.
"Rocket" is a collective name used to term some species within the Eruca and Diplotaxis genera, whose leaves are characterized by a more or less pungent taste. Different approaches have been carried out to differentiate both genera that have similar leaf morphologies. Following our research in flavonoid profiling of the Brassicaceae family using high-performance liquid chromatography/ultraviolet-diode array detection/electrospray ionization mass spectroemtry, we have investigated Eruca vesicaria and Diplotaxis tenuifolia leaf samples as new ingredients of fresh salads. The MS/MS study allowed the identification of new naturally occurring quercetin mono- and diacyl-tri-O-glucosides and the elucidation of the flavonoid glycosylation and acylation patterns. Important differences between flavonoid profiles of E. vesicaria and D. tenuifolia were observed. E. vesicaria contained kaempferol derivatives as principal compounds whereas D. tenuifolia instead accumulated quercetin derivatives. The exhaustive study of the profiling of these species could help further studies concerning the bioavailability of these flavonoids for epidemiological or clinical intervention studies because these species have considerable potential as healthy leafy salads because of the bioactive phytochemicals.  相似文献   

18.
Red leaf lettuce (Lollo Rosso) was grown under three types of plastic films that varied in transparency to UV radiation (designated as UV block, UV low, and UV window). Flavonoid composition was determined by high-performance liquid chromatography (HPLC), total phenolics by the Folin-Ciocalteu assay, and antioxidant capacity by the oxygen radical absorbance capacity (ORAC) assay. Exposure to increased levels of UV radiation during cultivation caused the leaves to redden and increased concentrations of total phenols and the main flavonoids, quercetin and cyanidin glycosides, as well as luteolin conjugates and phenolic acids. The total phenol content increased from 1.6 mg of gallic acid equivalents (GAE)/g of fresh weight (FW) for lettuce grown under UV block film to 2.9 and 3.5 mg of GAE/g of FW for lettuce grown under the UV low and UV window films. The antioxidant activity was also higher in lettuce exposed to higher levels of UV radiation with ORAC values of 25.4 and 55.1 micromol of Trolox equivalents/g of FW for lettuce grown under the UV block and UV window films, respectively. The content of phenolic acids, quantified as caffeic acid, was also different, ranging from 6.2 to 11.1 micromol/g of FW for lettuce cultivated under the lowest and highest UV exposure plastic films, respectively. Higher concentrations of the flavonoid glycosides were observed with increased exposure to UV radiation, as demonstrated by the concentrations of aglycones after hydrolysis, which were cyanidin (ranging from 165 to 793 microg/g), quercetin (ranging from 196 to 880 microg/g), and luteolin (ranging from 19 to 152 microg/g). The results demonstrate the potential of the use of UV-transparent plastic as a means of increasing beneficial flavonoid content of red leaf lettuce when the crop is grown in polytunnels.  相似文献   

19.
Chrysanthemum morifolium extract (CME) has the protective effect on cardiovascular diseases. Luteolin and apigenin are two major bioactive components in vivo when CME is orally administrated to experimental animal. The present paper shows the study of the absorption and excretion of luteolin and apigenin in rats after a single oral dose of CME (200 mg/kg). The levels of luteolin and apigenin in plasma, urine, feces, and bile were measured by HPLC after deconjugation with hydrochloric acid or beta-glucuronidase/sulfatase. The results showed that the plasma concentrations of luteolin and apigenin reached the highest peak level at 1.1 and 3.9 h after dosing, respectively. The area under the concentration-time curves (AUC) for luteolin and apigenin were 23.03 and 237.6 microg h mL-1, respectively. The total recovery of the dose was 37.9% (6.6% in urine; 31.3% in feces) for luteolin and 45.2% (16.6% in urine; 28.6% in feces) for apigenin. The cumulative luteolin and apigenin excreted in the bile was 2.05% and 6.34% of the dose, respectively. All of the results suggest apigenin may be absorbed more efficiently than luteolin in CME in rats, and both luteolin and apigenin have a slow elimination phase, with a quick absorption, so a possible accumulation of the two flavonoids in the body can be hypothesized.  相似文献   

20.
The fate of dichlorvos (DDVP) on dates after storage and processing of postharvest-treated fruits has been investigated. Residues were determined using GC-ECD after extraction of the fruits. A postharvest application was made to fruits at different stages of maturity: khalal fruits (mature full colored stage), rutab fruits (soft brown stage), and the mature tamer fruits (hard raisin-like stage). The fate of the residues was followed during the storage at refrigerated, room, and summer average temperatures (3, 22, and 43 degrees C). The amount of residues absorbed varied with the level of maturity. The rate of the loss of the residues was found to follow first-order kinetics. First-order rate constants were calculated for the different levels of maturity. The rate of the loss of DDVP increased as the temperature of storage increased. Also, it decreased with increasing maturation of the dates, which was characterized by a decrease in moisture content as well as water activity and an increase in sugar content. The period of storage study was limited by the time of maturation to the next stage. Most common home-cooking methods, including dehydration, jam-making, and syrup-making, resulted in significant decreases in residue levels. Only 0-13% of initial DDVP residues was detected in final products.  相似文献   

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