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A strategy was developed for the identification of saponins in Alliums using ultra-high performance liquid chromatography high-resolution accurate-mass/multi-stage mass spectrometry (UHPLC-HRAM/MSn). The identification process was facilitated by a systematic classification of 152 previously reported sapogenins (saponin aglycones) in Allium based on their structural characteristics. The approach was successfully applied to putatively identify a total of 108 steroidal saponins in scallions, giant green onions, petite sweet Vidalia onions, and leeks using HRAM mass values and diagnostic fragmentation ions rapidly. Seventeen of the saponins are reported in genus Allium for the first time.

A new computational tool is proposed here for tentatively identifying major (UV quantifiable) flavone/flavonol glycoside peaks of high performance liquid chromatogram (HPLC)-diode array detection (DAD)-tandem mass spectrometry (MS/MS) profiles based on a MATLAB-based script implementing an in-house algorithm. The HPLC-DAD-MS/MS profiles of red onion, Chinese lettuce, carrot leaf, and celery seed extracts were analyzed by the proposed computer-aided screening method for identifying possible flavone/flavonol glycoside peaks from the HPLC-UV and MS total ion current (TIC) chromatograms. The number of identified flavone/flavonol glycoside peaks of the HPLC-UV chromatograms is four, four, six, and nine for red onion, Chinese lettuce, carrot leaf, and celery seed, respectively. These results have been validated by human(s) experts. For the batch processing of nine HPLC-DAD-MS/MS profiles of celery seed extract, the entire script execution time was within 15 s while manual calculation of only one HPLC-DAD-MS/MS profile by a flavonoid expert could take hours. Therefore, this MATLAB-based screening method is able to facilitate the HPLC-DAD-MS/MS analysis of flavone/flavonol glycosides in plants to a large extent.

Oligomeric proanthocyanidins were successfully identified by UHPLC-PDA-HRMS(n) in a selection of plant-derived materials (jujube fruit, Fuji apple, fruit pericarps of litchi and mangosteen, dark chocolate, and grape seed and cranberry extracts). The identities of 247 proanthocyanidins were theoretically predicted by computing high-accuracy masses based on the degree of polymerization, flavan-3-ol components, and the number of A type linkages and galloyls. MS(n) fragments allowed characterization on flavan-3-ol based on the monomer, connectivity, and location of A-type bonds. Identification of doubly or triply charged ions of 50 PAs was made on the basis of theoretical calculations. A single catechin standard and molar relative response factors (MRRFs) were used to quantify the well-separated PAs. The ratios of the SIM peak counts were used to quantify each of the unseparated isomers. This is the first report of direct determination of each of the proanthocyanidins in plant-derived foods and proanthocyanidins containing an epifisetinidol unit in grape seeds.

The hepatoprotective potential of ethanolic extract of Cardiospermum halicacabum (ECH) was evaluated in Wistar rats having liver injury induced by CCl4. The free radical scavenging activity of ECH was evaluated by ABTS and DPPH assay. Phenolic compounds like luteolin 7-o-glucoronide, apigenin 7-o-glucoronide and chrysoerisol 7-o-glucoronide were identified in ECH by UPLC–MS/MSn analysis. On the other hand, the anti mutagenic effect of ECH was examined using tester strain Salmonella typhimurium TA100 with and without S9 extract. CCl4 administered Wistar rats exhibited alteration in various biochemical parameters which were significantly (P ⩽ 0.05) restored toward normal level by the therapy of ECH. ECH significantly (P ⩽ 0.05) reduced LPO level in the liver tissue. Treatment with ECH showed curative effect on histopathological alterations and DNA damage in CCl4 administered rats in a dose dependent manner. Silymarin, a routine hepatoprotective drug was used as reference standard.

RATIONALE Traditionally, anthocyanin analysis in mass spectrometry is carried out in the positive ionization mode only. A study of the mass spectrometric behaviors of anthocyanins in the negative ionization mode revealed interesting characteristics that was not previously reported. It can be used to differentiate anthocyanins from other non-anthocyanin polyphenols. METHODS An ultra-high-performance liquid chromatography with high-resolution mass spectrometry (U-HPLC/HRMS) method was developed. The method used multiple-stage mass fragmentation in both the negative and positive ion modes. The whole cycle time of the new method is 1.8 s for two full scans and six data-dependent scans. RESULTS The new strategy found, in the negative ionization mode, a series of characteristic ions, e.g. [M–2H]–, [M–2H + H2O]– , formic acid adducts, and doubly charged ions were observed for the MS analysis of anthocyanins. The characteristic ions can be used for identification and differentiation of anthocyanins and non-anthocyanin phenolic compounds. Comprehensive studies were performed on the differentiation of anthocyanins and non-anthocyanin polyphenols in blueberry (Vaccinium cyanococcus), Hongcaitai (Brassica compestris L. var. purpurea Bailey), and red radish (Raphanus sativus var. longipinnatus 'Shinrimei'). CONCLUSIONS The data generated from a single LC run enables rapid and reliable differentiation and identification of anthocyanins and non-anthocyanins in botanicals and foods. Published 2012. This article is a US Government work and is in the public domain in the USA.

An UHPLC-PDA-ESI/HRMS/MS(n) profiling method was used for a comprehensive study of the phenolic components of red mustard greens ( Brassica juncea Coss variety) and identified 67 anthocyanins, 102 flavonol glycosides, and 40 hydroxycinnamic acid derivatives. The glycosylation patterns of the flavonoids were assigned on the basis of direct comparison of the parent flavonoid glycosides with reference compounds. The putative identifications were obtained from tandem mass data analysis and confirmed by the retention time, elution order, and UV-vis and high-resolution mass spectra. Further identifications were made by comparing the UHPLC-PDA-ESI/HRMS/MS(n) data with those of reference compounds in the polyphenol database and in the literature. Twenty-seven acylated cyanidin 3-sophoroside-5-diglucosides, 24 acylated cyanidin 3-sophoroside-5-glucosides, 3 acylated cyanidin triglucoside-5-glucosides, 37 flavonol glycosides, and 10 hydroxycinnamic acid derivatives were detected for the first time in brassica vegetables. At least 50 of them are reported for the first time in any plant materials.

Tea (Camellia sinensis L.), an important drink and a natural medicine for thousands of years, contains many health beneficial compounds. Growing season, geographical region, and fermentation methods create many variations in tea compositions, which contribute to each tea's uniqueness. In this study, a simple, rapid, and efficient ultra-performance liquid chromatography (UPLC) method combined with diode array detector (DAD) and mass spectroscopic (MS) detection and chemometrics analysis was used to analyse three different types of teas (green pu-erh, green tea, white tea). Using the developed method, 68 compounds were identified and 54 were quantified based on retention times, UV spectra, and MS spectra by referencing to available standards and data in the literatures. The results showed the chemical differences between the tested teas. Principal component analysis (PCA) was applied to classify and distinguish between tea samples.

An LC-PDA-ESI/MS(n) profiling method was used to identify the anthocyanins of purple Bordeaux radish and led to the assignment of 60 anthocyanins: 14 acylated cyanidin 3-(glucosylacyl)acylsophoroside-5-diglucosides, 24 acylated cyanidin 3-sophoroside-5-diglucosides, and 22 acylated cyanidin 3-sophoroside-5-glucosides. The identifications were supported by the presence of 3-sophoroside-5-diglucoside and 3-sophroside-5-glucoside of cyanidin in the alkaline-hydrolyzed extract. A reliable method to identify the anthocyanins containing 3-(glucosylacyl)acylsophorosyl functions is described. The tentative identifications were obtained from tandem mass data analysis and confirmed by high-resolution mass measurements. Further assignments were made for some anthocyanins from a comparison of the mass and UV-vis data and elution order with those of the anthocyanins in the authors' polyphenol database and from consideration of the structural characteristics of the anthocyanins from similar plants and similar anthocyanins in the literature. The presence of 38 acylated cyanidin 3-sophoroside-5-diglucosides and around 10 acylated cyanidin 3-sophoroside-5-malonylglucosides in plants is reported here for the first time.

Green tea-based dietary supplements (GTDSs) have gained popularity in the U.S. market in recent years. This study evaluated the phytochemical composition difference of GTDS in comparison with green tea leaves using an HPLC/MS fingerprinting technique coupled with chemometric analysis. Five components that are most responsible for class separation among samples were identified as (-) epicatechin gallate, strictinin, trigalloylglucose, quercetin-3-O-glucosylrhamnosylglucoside, and kaempferol-3-O-galactosyl-rhamnosylglucoside, according to the accurate mass measurements and MS/MS data. The similarity coefficients between the GTDSs in solid form with green tea were 0.55 to 0.91, while for the GTDSs in liquid form they were 0.12 to 0.89, which suggested that chemical composition variance across the GTDSs was significant. Flavonol aglycone concentrations were higher in GTDSs than in tea leaves, indicating the degradation of flavonol glycosides or the oxidation of catechin during the manufacturing and storage processes. In some GTDS samples, compounds were identified that were on the label. The results demonstrate the urgency of QC for GTDS products.

Scutellaria lateriflora, commonly known as skullcap, is used as an ingredient in numerous herbal products. However, it has been occasionally adulterated/contaminated with Teucrium canadense and T. chamaedrys, commonly known as germander, which contain hepatotoxic diterpenes. Due to the morphological similarities between the two genera, analytical methodologies to distinguish authentic S. lateriflora from the Teucrium species are needed to ensure public safety. In this study, a direct-injection electrospray ionization/MS method was used to generate spectral fingerprints of extracts from 21 skullcap and germander samples at a rate of 90 s/sample. MS fingerprints were analyzed by principal component analysis. The newly developed method offers a rapid and easy way to differentiate between skullcap and germander samples.

A liquid chromatography-mass spectrometry (LC-MS) profiling method was used to characterize the phenolic components of 17 leafy vegetables from Brassica species other than Brassica oleracea. The vegetables studied were mustard green, baby mustard green, gai choy, baby gai choy, yu choy, yu choy tip, bok choy, bok choy tip, baby bok choy, bok choy sum, Taiwan bok choy, Shanghai bok choy, baby Shanghai bok choy, rapini broccoli, turnip green, napa, and baby napa. This work led to the tentative identification of 71 phenolic compounds consisting of kaempferol 3-O-diglucoside-7-O-glucoside derivatives, isorhamnetin 3-O-glucoside-7-O-glucoside hydroxycinnamoyl gentiobioses, hydroxycinnamoylmalic acids, and hydroxycinnamoylquinic acids. Ten of the compounds, 3-O-diacyltriglucoside-7-O-glucosides of kaempferol and quercetin, had not been previously reported. The phenolic component profiles of these vegetables were significantly different than those of the leafy vegetables from B. oleracea. This is the first comparative study of these leafy vegetables. Ten of the vegetables had never been previously studied by LC-MS.

A standardised profiling method based on liquid chromatography with diode array and electrospray ionisation/mass spectrometry (LC–DAD–ESI/MS) was used to identify 46 flavonoids and 17 caffeic acid derivatives in the aqueous methanol extract of Flos chrysanthemum (Chrysanthemum morifolium Ramat) (Compositae), an important Chinese herb. Fifteen caffeoylquinic acids and 15 flavonoids were positively identified and the remaining compounds were provisionally identified. The detected phenolics were present at concentrations greater than 0.001% of the dry plant material. Many of these phenolics have been reported to have human health benefits. Twenty-five compounds, including C-glycosylated flavones and aliphatic acid-containing caffeoylquinic acids, are reported for the first time in chrysanthemum flower, and this comprehensive analysis of the phenolic components of herb Flos chrysanthemum will be helpful for the quality control of this herb and its products, and to understand the usage and function.

An LC-MS profiling method was used for a comprehensive study of the phenolic components of collard greens, kale, and Chinese broccoli, three Brassica green leafy vegetables. This study led to the identification of 45 flavonoids and 13 hydroxycinnamic acid derivatives in the three vegetables. Most of the identifications were based on comparison of compounds previously reported in the literature for Brassica vegetables. The results indicate that the three materials have very similar phenolic component profiles. For each, kaempferol glycosides and acylgentiobiosides were the major phenolic compounds, quercetin glycosides were minor compounds, and most of the flavononol glycosides existed in their acylated forms. In addition, each of the materials contained caffeoyl-, p-coumaroyl-, and feruloylquinic acid monomers with a 3-position derivative as the dominant isomer. This is the first report for most of these phenolics in collard greens and Chinese broccoli and for >20 of them in kale.

The bark of maritime pine (Pinus pinaster Aiton) has been widely used as a remedy for various degenerative diseases. A standard high-performance liquid chromatographic (HPLC) procedure for Pycnogenol® analysis is a method specified in the United States Pharmacopeia (USP) monograph, which requires measurement of peak areas and identification of four components of the extract: caffeic acid, catechin, ferulic acid, and taxifolin. In this study, a fingerprint analysis using an HPLC method based on the USP monograph has been developed to provide additional qualitative information for the analysis of Pycnogenol-containing dietary supplements (PDS). Twelve commercially available PDS samples were purchased and analyzed along with a standard Pycnogenol extract. Their chromatographic fingerprints were analyzed using principal component analysis. The results showed that two of the samples were not consistent with the standard reference Pycnogenol extract. One contained other active ingredients in addition to Pycnogenol, and the other may have resulted from a quality control issue in manufacturing.

Metabolite fingerprints, obtained with direct injection mass spectrometry (MS) with both positive and negative ionization, were used with analysis of variance-principal components analysis (ANOVA-PCA) to discriminate between cultivars and growing treatments of broccoli. The sample set consisted of two cultivars of broccoli, Majestic and Legacy, the first grown with four different levels of Se and the second grown organically and conventionally with two rates of irrigation. Chemical composition differences in the two cultivars and seven treatments produced patterns that were visually and statistically distinguishable using ANOVA-PCA. PCA loadings allowed identification of the molecular and fragment ions that provided the most significant chemical differences. A standardized profiling method for phenolic compounds showed that important discriminating ions were not phenolic compounds. The elution times of the discriminating ions and previous results suggest that they were common sugars and organic acids. ANOVA calculations of the positive and negative ionization MS fingerprints showed that 33% of the variance came from the cultivar, 59% from the growing treatment, and 8% from analytical uncertainty. Although the positive and negative ionization fingerprints differed significantly, there was no difference in the distribution of variance. High variance of individual masses with cultivars or growing treatment was correlated with high PCA loadings. The ANOVA data suggest that only variables with high variance for analytical uncertainty should be deleted. All other variables represent discriminating masses that allow separation of the samples with respect to cultivar and treatment.

LC-DAD-ESI/MS was used to identify 23 flavonoids in the extract of Mexican oregano (Lippia graveolens H.B.K.), a spice and herb, used in the USA and Mexico. The identification of luteolin-7-O-glucoside, apigenin 7-O-glucoside, phloridzin, taxifolin, eriodictyol, scutellarein, luteolin, quercetin, naringenin, pinocembrin and galangin was confirmed by direct comparison with standards. Identification of 6-hydroxyluteolin, two 6-hydroxyluteolin 7-O-glycosides, three pentahydroxyflavanone hexosides, scutellarein 7-O- hexoside, 3-hydroxyphloretin hexoside, and three other flavones, was made by detailed analysis of their UV and mass spectral data. The identification of the flavonoid glycosides was further confirmed through detection of their aglycones following hydrolysis of the samples. The concentration of the identified flavonoids in three samples was also estimated. This is the first report of detection of over 20 flavonoids, including chalcones, in this plant material.

Profiling methods are needed that separate and detect all the phenolic compounds in a single extract of a food material. These methods must be comprehensive, rapid, and rich in spectral information. Fourteen methods that meet, or have the potential to meet, these criteria have been selected from the recent literature for review. In general, the methods employ a single aqueous methanol extraction, separation on a reversed-phase C column, and detection by UV/vis spectroscopy and mass spectrometry. The variations in extraction, separation, and detection are discussed. An increasingly important aspect of these methods is the archiving of data to permit cross-comparison of samples and standards and retrospective analysis. This review shows that the necessary technology is available to achieve the desired analytical goals.

Liquid chromatography, with diode array detection and electrospray ionization mass spectrometry (LC-DAD-ESI/MS), was used to identify and quantify flavonoids in cashew apple. One anthocyanin and thirteen glycosylated flavonols were detected in a methanol-water extract. Among them, the 3-O-galactoside, 3-O-glucoside, 3-O-rhamnoside, 3-O-xylopyranoside, 3-O-arabinopyranoside and 3-O-arabinofuranoside of quercetin and myricetin, as well as kaempferol 3-O-glucoside were identified by direct comparison with standards or positively identified flavonoids in cranberry. The anthocyanin was the 3-O-hexoside of methyl-cyanidin. Trace amounts of delphinidin and rhamnetin were detected in the hydrolyzed extract, suggesting their glycosides were present, but undetectable, in the original extract. The concentrations of the 14 flavonoids in the tested sample were determined. This is the first report of these flavonoids in cashew apple.

The major flavonoid of the aerial parts of Echinacea angustifolia was found to be patuletin-3- O -rutinoside (1), rather than rutin (2), as reported previously. The related amount of patuletin-3- O -rutinoside is 5-8-times higher than that of rutin in the tested samples. Patuletin-3- O -rutinoside also existed in the aerial parts of E. purpurea and E. pallida, and the first complete NMR assignment of patuletin-3- O -rutinoside was made by using 2D NMR techniques. This is the first report of the occurrence of patuletin-3- O -rutinoside in Echinacea species.

Based on the phenolic profiles obtained by high performance liquid chromatography-electrospray ionization mass spectrometry (HPLC-DAD-ESI/MS), 24 common bean samples, representing 17 varieties and 7 generic off-the-shelf items, belonging to ten US commercial market classes can be organized into six different groups. All of them contained the same hydroxycinnaminic acids, but the flavonoid components showed distinct differences. Black beans contained primarily the 3-O-glucosides of delphinidin, petunidin and malvidin, while pinto beans contained kaempferol and its 3-O-glycosides. Light red kidney bean contained traces of quercetin 3-O-glucoside and its malonates, but pink and dark red kidney beans contained the diglycosides of quercetin and kaempferol. Small red beans contained kaempferol 3-O-glucoside and pelargonidin 3-O-glucoside, while no flavonoids were detected in alubia, cranberry, great northern, and navy beans. This is the first report of the tentative identification of quercetin 3-O-pentosylhexoside and flavonoid glucoside malonates, and the first detailed detection of hydroxycinnamates, in common beans.

Liquid chromatography, with diode array detection and electrospray ionization mass spectrometry (LC-DAD-ESI/MS), was used to identify and quantify flavonoids in cashew apple. One anthocyanin and thirteen glycosylated flavonols were detected in a methanol–water extract. Among them, the 3-O-galactoside, 3-O-glucoside, 3-O-rhamnoside, 3-O-xylopyranoside, 3-O-arabinopyranoside and 3-O-arabinofuranoside of quercetin and myricetin, as well as kaempferol 3-O-glucoside were identified by direct comparison with standards or positively identified flavonoids in cranberry. The anthocyanin was the 3-O-hexoside of methyl-cyanidin. Trace amounts of delphinidin and rhamnetin were detected in the hydrolyzed extract, suggesting their glycosides were present, but undetectable, in the original extract. The concentrations of the 14 flavonoids in the tested sample were determined. This is the first report of these flavonoids in cashew apple.

An UHPLC-PDA-ESI/HRMS(n) profiling method was used to identify the glucosinolates and flavonoids of Rorippa indica (Cruciferae), a wild vegetable and Chinese herb used to treat cough, diarrhea, and rheumatoid arthritis. Thirty-three glucosinolates, more than 40 flavonol glycosides, and 18 other phenolic and common organic compounds were identified. The glucosinolates and polyphenols were separated by UHPLC. High-resolution deprotonated molecules provided high accuracy mass values that were used to determine formulas and provide putative identification of the glucosinolates and flavonoids. The fragments from multistage mass spectrometry were used to elucidate the structures. The concentrations of the main components were based on UV peak areas and molar relative response factors with a single calibration standard. This study found this plant to be a rich source for glucosinolates, containing 24 new glucosinolates, including 14 glucosylated glucosinolates that were previously unidentified.

LC-DAD-ESI/MS was used to identify 23 flavonoids in the extract of Mexican oregano (Lippia graveolens H.B.K.), a spice and herb, used in the USA and Mexico. The identification of luteolin-7-O-glucoside, apigenin 7-O-glucoside, phloridzin, taxifolin, eriodictyol, scutellarein, luteolin, quercetin, naringenin, pinocembrin and galangin was confirmed by direct comparison with standards. Identification of 6-hydroxyluteolin, two 6-hydroxyluteolin 7-O-glycosides, three pentahydroxyflavanone hexosides, scutellarein 7-O-hexoside, 3-hydroxyphloretin hexoside, and three other flavones, was made by detailed analysis of their UV and mass spectral data. The identification of the flavonoid glycosides was further confirmed through detection of their aglycones following hydrolysis of the samples. The concentration of the identified flavonoids in three samples was also estimated. This is the first report of detection of over 20 flavonoids, including chalcones, in this plant material.

Irroratin A (1), isolated from the aerial Darts of Isodon irrorata (Forrest.) (Labiatae), was shown to be an equimolecular mixture of two C-20 epimers of a new ent-kaurene diterpene both in the crystalline state and pyridine solution, based on X-ray, LC/MS/MS, FABMS as well as extensive 1D- and 2D-NMR spectral analysis. The two epimers were hound together by hydrogen bonds, and when in chloroform and methanol solution, the 20S-epimer predominates. Irroratin A exhibited potent cytotoxicity against several human cancer cell lines. (C) 2000 Elsevier Science Ltd. All rights reserved.

A method is developed for qualitative analysis of ginkgolic acids in the leaves and fruits of Ginkgo biloba by high-performance liquid chromatography (HPLC)-electrospray ionization-mass spectrometry technique. Negative ionization mode is successful in obtaining a very abundant deprotonated molecule [M - H] - . The mass detection sensitivity is higher than ultraviolet detection but relies heavily on the concentration of acetic acid in the HPLC eluent, which consists of acetonitrile-water-acetic acid. The method is also very specific for the analysis of ginkgolic acid with no interferences from the sample matrix.

High-performance liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS) was applied to the analysis of the flavonoids and their glycoside malonates of the flowers and leaves of red clover (Trifolium pratense). Through LC-MS comparative studies on the plant extracts and their malonate-free extracts, approximately 20 flavonoid glycoside malonates were detected in the flower extract. Eight were identified as genistin 6' '-O-malonate (39), formononetin 7-O-beta-D-glucoside 6' '-O-malonate (40), biochanin A 7-O-beta-D-glucoside 6' '-O-malonate (41), trifoside 6' '-O-malonate (42), irilone 4'-O-beta-D-glucoside 6' '-O-malonate (43), pratensein 7-O-beta-D-glucoside 6' '-O-malonate (44), isoquercitrin 6' '-O-malonate (45), and 3-methylquercetin 7-O-beta-D-glucoside 6' '-O-malonate (46). About 15 other flavonoids and clovamides were proved to be present in this extract. The study also found that the flowers contained flavones as the major flavonoids, whereas the leaves had isoflavones as the major flavonoids. This is the first detection of the six malonates (39 and 42-46) in the extracts of red clover, and among them, 42, 43, and 46 are new compounds.

On-line high-performance liquid chromatography–UV diode-array and electrospray mass spectrometry have been used simultaneously to analyze curcuminoids and sesquiterpenoids in a fresh turmeric (Curcuma longa) extract. Five major components: curcumin (1), demethoxycurcumin (2), bisdemethoxycurcumin (3), ar-turmerone (5) and curlone (6) have been unambiguously identified, based on their UV spectra, mass spectra and retention times in comparison with the data of standard compounds. This method provides a reliable fingerprint for turmeric, distinguishing it from other Curcuma species.

High-performance liquid chromatography–electrospray ionization–mass spectrometry has been applied to analyze the chemical constituents of Danggui (the rhizome of Angelica sinensis) and to study chemical changes of Z-ligustilide. Twelve phthalides were unambiguously identified as senkyunolide I (3), senkyunolide H (4), sedanenolide (8), butylphthalide (9), E-ligustilide (13), Z-ligustilide (14), Z-butylidenephthalide (15), Z,Z′-6.8′,7.3′-diligustilide (16), angelicide (17), levistolide A (18), Z-ligustilide dimer E-232 (19) and Z,Z′-3.3′,8.8′-diligustilide (20) in Danggui extract. The existence of 12 other phthalides (2, 5–7, 11, 12, 22–27), ferulic acid (1) and coniferyl ferulate (10) in Danggui extract has also been demonstrated. Phthalides 3, 4, 16–18 and 20 were determined to be the products from chemical change of Z-ligustilide. This is the first report of the existence of 16 compounds (2–8, 10–12, 20, 22–25 and 27) in Danggui extract.

A gradient elution reversed-phase HPLC separation of ginger extract has been developed, which gives better separation than previous isocratic separations. HPLC–UV–electrospray MS has been successfully utilized to identify the individual pungent constituents in the chromatogram of ginger extract. Seven compounds were positively identified as the major pungent constituents of ginger based on their UV spectra, [M+H] + , [M+Na] + and characteristic sodiated dimer [2M+Na] + ions, and comparison to data for the purified standards: [6]-gingerol and [6]-shogaol. The pungent compounds were assigned as [6]-gingerol, [8]-gingerol, [10]-gingerol, [6]-shogaol, [8]-shogaol, [10]-shogaol and [6]-gingediol. Another eight minor compounds were tentatively identified as gingerol analogues.

High-performance liquid chromatography coupled with a UV photodiode-array detector and an electrospray mass spectrometer (HPLC–ES-MS) was used to analyze the phytochemical constituents of an extract of sour orange ( Citrus aurantium L., family Rutaceae). Eight flavonoids were identified, as isonaringin ( 1 ), naringin ( 3 ), hesperidin ( 5 ), neohesperidin ( 6 ), naringenin ( 2 ), hesperitin ( 4 ), nobiletin ( 8 ) and tangeritin ( 7 ). The permethoxylated flavones tangeritin ( 7 ) and nobiletin ( 8 ) showed the most intense protonated molecules. This method can be used to detect trace amounts of these compounds in an orange extract.

Two new pyranoflavanones, 2‴,3‴-epoxylupinifolin and dereticulatin, together with the known flavonoid lupinifolin, were identified from the stems of Derris reticulata . The structures and NMR spectral data were assigned by the use of 2D NMR technology and chemical transformations. All of the isolates showed cytotoxic activity in the P-388 cell line.

Two tetracyclic diterpene polyesters, paralinones A and B, with a new carbon framework, were isolated from an acetone extract of the whole plant of Euphorbia paralias. The structures of the compounds were elucidated by high field spectroscopic methods, including 2D NMR techniques and X-ray crystallography.

HPLC coupled with electrospray (ES) MS was used to study a chloroform extract from kava roots ( PIPER METHYSTICUM). A total of thirteen kavalactones and flavokavains were identified. Seven major kavalactones, methysticin, dihydromethysticin, kavain, 7,8-dihydrokavain, 5,6-dehydrokavain, 5,6-dehydromethysticin and yangonin, were easily recognized in the extract by their [M + H] (+) or [M + Na] (+) ions, UV spectra, and retention times, compared with those of standard compounds. Six minor constituents were isolated as our own reference compounds. These constituents were identified by their [M + H] (+) or [M + Na] (+) ions, UV spectra and NMR data as 11 -hydroxy-12-methoxydihydrokavain, 7,8-dihydro-5-hydroxy-kavain, 11,12-dimethoxydihydrokavain, and flavokavains A, B and C. HPLC-ES-MS appears to be a suitable technique for identification of kavalactones and kavachalcones in the kava extract. The method also provides direct guidance for identification of other trace constituents from kava extracts.

An electrospray high-performance liquid chromatography-mass spectrometry interface coupled with a photodiode-array detector has been applied successfully to the identification of a number of lignan constituents from an ethanol extract of the fruits of Schisandra chinensis Baill. A total of fifteen peaks were identified, six of them unambiguously identified as schisandrin (1), schisantherin A (19), schisantherin B (20), schisanhenol (4), deoxyschisandrin (3) and γ-schisandrin (11), based on their abundant [M+H] + , [M+Na] + ions, UV spectra and retention times, compared with those data of reference compounds. Another nine peaks were tentatively identified, based on their intense [M+H] + and [M+Na] + ions and UV spectra.

Brassica vegetables are known to contain relatively high concentrations of bioactive compounds associated with human health. A comprehensive profiling of polyphenols from five Brassica species microgreens was conducted using ultra high-performance liquid chromatography photo diode array high-resolution multi-stage mass spectrometry (UHPLC-PDA-ESI/HRMSn). A total of 164 polyphenols including 30 anthocyanins, 105 flavonol glycosides, and 29 hydroxycinnamic acid and hydroxybenzoic acid derivatives were putatively identified.The putative identifications were based on UHPLC-HRMSn analysis using retention times, elution orders, UV/Vis spectra and high resolution mass spectra, in-house polyphenol database, and as well as literature comparisons. This study showed that these five Brassica species microgreens could be considered as good sources of food polyphenols.

A high-performance liquid chromatographic method paired with photodiode-array and electrospray mass spectrometer detectors enables us to rapidly characterize the flavonoid constituents from red clover. A total of eleven flavonoids were identified. Among them, seven flavonoids - genistin, isoquercitrin, ononin, daidzein, sissotrin, formononetin and biochanin A - were unambiguously identified based on their abundant [M + H] + , [M + Na] + ions, UV spectra, retention time and analysis of hydrolyzed products. The purity of three peaks, for pratensein, pectolinarigenin and pseudobaptigenin, is not enough to have predominant [M + H] + or [M + Na] + ions, but their existence is believable. Hyperoside has intense [M + H] + and [M + Na] + ions. Its identification is still tentative, because there are severa; other quercetin glycosides which will have the same [M + H] + ion.

A new indole alkaloid, was isolated from Gelsemium elegans, 19α-hydroxygelsamydine and its stereochemistry and 1H and 13C-NMR data were determined by two-dimensional NMR techniques, computer modelling calculations and comparison with gelsamydine.

Two new polyoxypregnanes, designated marstenacigenins A and B, along with a known compound, dresgenin, were isolated from the mild acid hydrolysate of the ethanol extract of the stems of Marsdenia tenacissima. Their structures were deduced by a combination of 1D and 2D NMR spectroscopic techniques as 12 beta-cinnamoyl-dihydrosarcostin and 12 beta,20-dibenzoyldihydrosarcostin, respectively.

From Hymenocallis littoralis, one new alkaloid, named littoraline, together with 13 known lycorine alkaloids and one lignan, were isolated. The structure and NMR assignments of this new alkaloid were determined by 1D and 2D NMR techniques. Littoraline showed inhibitory activity of HIV reverse transcriptase, and lycorine and haemanthamine showed potent in vitro cytotoxicity.

Reinvestigation of the NMR spectra of gymnemarsgenin by the selective INEPT and various two-dimensional NMR techniques (DQF-COSY, ROESY, HETCOR) led to the structural revision of gymnemarsgenin as 12 β - O -cinnamoyl-20- O -benzoyl sarcostin. The 1 H and 13 C NMR spectra were completely assigned. It is apparent that the 12-cinnamoyl group migrated to C-20 under the mild alkaline conditions rendered for partial saponification.

Two new medicagenic acid saponins, named asterbatanoside J and K, were isolated from the roots of Aster batangensis. On the basis of chemical and spectral studies especially 2D NMR including COSY, HETCOR, HMQC, HOHAHA, TOCSY, ROESY and HMBC techniques, their structures were established as 3-O-β- d -glucopyranosyl-(1→6)-β- d -glucopyranosyl-2β,3β-dihydroxy-olean-12-en-23α,28-dioic acid -28-O-α- l -arabinopyranosyl-(1→3)-α- l -rhamnopyranosyl-(1→2)-β- d -fucopyranoside and 3-O-β- d -glucopyranosyl-(1→6)-β- d -glucopyranosyl-medicagenic acid -28-O-β- d -xylopyranosyl-(→4)-[α- l -arabinopyranosyl-(1→3)-]-α- l -rhamnopyranosyl-(1→2)-β- d -fucopyranside , respectively.

Four new triterpene saponins, asteryunnanosides A, B, C and D, have been isolated from Aster yunnanensis and their structures deduced as 2α,3β,23-trihydroxyolean-12-en-28-oic acid -28-O-α- l -rhamnopyranosyl -(1 → 2)-β- d -glucopyranoside , 2α,3β,23-trihydroxyolean-12-en-28-oic acid -28-O-β- d -glucopyranosyl -(1 → 2)-β- d -glucopyranoside , 2α,3β-dihydroxyolean-12-en-28-oic acid -28-O-α- l -rhamnopyranosyl -(1 → 2)-β- d -glucopyranoside and 2α,3β-dihydroxyolean-12-en-28-oic acid -28-O-β- d -glucopyranosyl -(1 → 2)-β- d -glucopyranoside , respectively, by means of spectral and chemical data.

From Isodon loxothyrsa , one new diterpenoid, loxothyrin A, together with one known diterpenoid, adenolin B, from I. pleiophyllus , three known diterpenoids, coetsoidins A, B and G, and from I. adenoloma , one known diterpenoid, longikaurin F, were isolated. The structure determination of loxothyrin A, and the unambiguous NMR spectral assignments of the known compounds were made by a combination of 1D and 2D NMR techniques and computer modelling calculations. The isolates showed potent cytotoxic activities.

Chamomile (Matricaria chamomilla L.), tarragon (Artemisia dracunculus L.) and Mexican arnica (Heterotheca inuoides) are common compositae spices and herbs found in the US market. They contain flavonoids and hydroxycinnamates that are potentially beneficial to human health. A standardized LC-PDA-ESI/MS profiling method was used to identify 51 flavonoids and 17 hydroxycinnamates. Many of the identifications were confirmed with authentic standards or through references in the literature or the laboratory’s database. More than half of the phenol compounds for each spice had not been previously reported. The phenolic profile can be used for plant authentication and to correlate with biological activities.

A general method was developed for the systematic quantitation of flavanols, proanthocyanidins, isoflavones, flavanones, dihydrochalcones, stilbenes, and hydroxybenzoic acid derivatives (mainly hydrolyzable tannins) based on UV band II absorbance arising from the benzoyl structure. The compound structures and the wavelength maximum were well correlated and were divided into four groups: the flavanols and proanthocyanidins at 278 nm, hydrolyzable tannins at 274 nm, flavanones at 288 nm, and isoflavones at 260 nm. Within each group, molar relative response factors (MRRFs) were computed for each compound based on the absorbance ratio of the compound and the group reference standard. Response factors were computed for the compounds as purchased (MRRF), after drying (MRRFD), and as the best predicted value (MRRFP). Concentrations for each compound were computed based on calibration with the group reference standard and the MRRFP. The quantitation of catechins, proanthocyanidins, and gallic acid derivatives in white tea was used as an example.

Traditionally, anthocyanin analysis in mass spectrometry is carried out in the positive ionization mode only. A study of the mass spectrometric behaviors of anthocyanins in the negative ionization mode revealed interesting characteristics that was not previously reported. It can be used to differentiate anthocyanins from other non-anthocyanin polyphenols.An ultra-high-performance liquid chromatography with high-resolution mass spectrometry (U-HPLC/HRMS) method was developed. The method used multiple-stage mass fragmentation in both the negative and positive ion modes. The whole cycle time of the new method is 1.8 s for two full scans and six data-dependent scans.The new strategy found, in the negative ionization mode, a series of characteristic ions, e.g. [M-2H](-), [M-2H + H(2)O](-), formic acid adducts, and doubly charged ions were observed for the MS analysis of anthocyanins. The characteristic ions can be used for identification and differentiation of anthocyanins and non-anthocyanin phenolic compounds. Comprehensive studies were performed on the differentiation of anthocyanins and non-anthocyanin polyphenols in blueberry (Vaccinium cyanococcus), Hongcaitai (Brassica compestris L. var. purpurea Bailey), and red radish (Raphanus sativus var. longipinnatus 'Shinrimei').The data generated from a single LC run enables rapid and reliable differentiation and identification of anthocyanins and non-anthocyanins in botanicals and foods. Published 2012. This article is a US Government work and is in the public domain in the USA.

Two novel triterpenoid saponins named asterbatanoside F ( 1 ) and G ( 2 ) were isolated from the roots of Aster batangensis and their structures elucidated as 3-O-β-D-glucopyranosyl-23-O-acetyl-bayogenin-28-O-β-D- glucopyranosyl-(1 → 6) - [α-L-rhamnopyranosyl-(1→2)] β-D-glucopyranoside and 3-O-β-D-glucopyranosyl-bayogenin-28-O-β-D-glucopyranosyl-(1→6)-[α-L-rhamnopyranosyl-(1→2)]-β-D-glucopyranoside by means of spectral data especially 2D NMR including COSY, HETCOR, COLOC, HOHAHA, ROESY and selective INEPT techniques and chemical evidence.