UHPLC-PDA-ESI/HRMSn profiling method to identify and quantify oligomeric proanthocyanidins in plant products.

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.

Profiling of glucosinolates and flavonoids in Rorippa indica (Linn.) Hiern. (Cruciferae) by UHPLC-PDA-ESI/HRMS(n).

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.

LC-PDA-ESI/MS identification of the phenolic components of three compositae spices: chamomile, tarragon, and Mexican arnica.

Chamomile (Matricaria chamomilla L.), tarragon (Artemisia dracunculus L.) and Mexican arnica (Heterotheca inuoides) are common compositae spices and herbs found in the US market.

Quantitation of flavanols, proanthocyanidins, isoflavones, flavanones, dihydrochalcones, stilbenes, benzoic acid derivatives using ultraviolet absorbance after identification by liquid chromatography-mass spectrometry.

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.

Study of the mass spectrometric behaviors of anthocyanins in negative ionization mode and its applications for characterization of anthocyanins and non-anthocyanin polyphenols.

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.

Quantitation of the hydroxycinnamic acid derivatives and the glycosides of flavonols and flavones by UV absorbance after identification by LC-MS.

A general approach was developed to quantify hydroxycinnamic acid derivatives and the glycosides of flavonols and flavones using UV molar relative response factors (MRRFs). More than 90 standards were analyzed by LC-MS and divided into five groups based on the λ(max) of their band I absorbance profiles. For each group, a commercially available standard was chosen as the group reference standard.

UHPLC-PDA-ESI/HRMS/MS(n) analysis of anthocyanins, flavonol glycosides, and hydroxycinnamic acid derivatives in red mustard greens (Brassica juncea Coss variety).

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.

A non-targeted approach to chemical discrimination between green tea dietary supplements and green tea leaves by HPLC/MS.

Green tea-based dietary supplements (GTDSs) have gained popularity in the U.S. market in recent years.

LC-PDA-ESI/MS(n) identification of new anthocyanins in purple Bordeaux radish ( Raphanus sativus L. variety).

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.

A comparison of analytical and data preprocessing methods for spectral fingerprinting.

Spectral fingerprinting, as a method of discriminating between plant cultivars and growing treatments for a common set of broccoli samples, was compared for six analytical instruments. Spectra were acquired for finely powdered solid samples using Fourier transform infrared (FT-IR) and Fourier transform near-infrared (NIR) spectrometry. Spectra were also acquired for unfractionated aqueous methanol extracts of the powders using molecular absorption in the ultraviolet (UV) and visible (VIS) regions and mass spectrometry with negative (MS-) and positive (MS+) ionization.

Mass spectroscopic fingerprinting method for differentiation between Scutellaria lateriflora and the germander (Teucrium canadense and T. chamaedrys) species.

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.

Phenolic component profiles of mustard greens, yu choy, and 15 other brassica vegetables.

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.

Identification of the phenolic components of collard greens, kale, and Chinese broccoli.

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.

Comparison of the phenolic component profiles of skullcap (Scutellaria lateriflora) and germander (Teucrium canadense and T. chamaedrys), a potentially hepatotoxic adulterant.

Introduction: Scutellaria lateriflora, commonly known as skullcap, is used as an ingredient in numerous herbal products. Unfortunately, it has occasionally been adulterated with Teucrium canadense or T. chamaedrys, commonly known as germander, which contains potentially hepatotoxic diterpenes.

Discriminating between cultivars and treatments of broccoli using mass spectral fingerprinting and analysis of variance-principal component analysis.

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.

Identification of hydroxycinnamoylquinic acids of arnica flowers and burdock roots using a standardized LC-DAD-ESI/MS profiling method.

A screening method using LC-DAD-ESI/MS was developed for the identification of common hydroxycinnamoylquinic acids based on direct comparison with standards. A complete standard set for mono-, di-, and tricaffeoylquinic isomers was assembled from commercially available standards, positively identified compounds in common plants (artichokes, asparagus, coffee bean, honeysuckle flowers, sweet potato, and Vernonia amygdalina leaves) and chemically modified standards. Four C18 reversed phase columns were tested using the standardized profiling method (based on LC-DAD-ESI/MS) for 30 phenolic compounds, and their elution order and retention times were evaluated.

Phenolic compounds and chromatographic profiles of pear skins (Pyrus spp.).

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.

New phenolic components and chromatographic profiles of green and fermented teas.

A standardized profiling method based on liquid chromatography with diode array and electrospray ionization mass spectrometric detection (LC-DAD-ESI/MS) was applied to establish the phenolic profiles of 41 green teas and 25 fermented teas. More than 96 phenolic compounds were identified that allowed the teas to be organized into five groups. Epigallocatechin gallate (EGCG) was the major phenolic component of green tea made from mature leaves (group 2), while green tea made from the younger buds and leaves (group 1) contained lower flavonoid concentrations.

Chromatographic profiles and identification of new phenolic components of Ginkgo biloba leaves and selected products.

Ginkgo biloba leaves and their extracts are one of the most widely used herbal products and/or dietary supplements in the world. A systematic study of the phenolic compounds is necessary to establish quality parameters. A modified LC-DAD-ESI/MS method was used to obtain chromatographic profiles for the flavonoids and terpene lactones of Ginkgo biloba leaves.

The polyphenolic profiles of common bean ( L.).

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--glucosides of delphinidin, petunidin and malvidin, while pinto beans contained kaempferol and its 3--glycosides.

Identification and quantification of flavonoids of Mexican oregano () by LC-DAD-ESI/MS analysis.

LC-DAD-ESI/MS was used to identify 23 flavonoids in the extract of Mexican oregano ( H.B.K.

Profiling methods for the determination of phenolic compounds in foods and dietary supplements.

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.

A screening method for the identification of glycosylated flavonoids and other phenolic compounds using a standard analytical approach for all plant materials.

A screening method was developed for the systematic identification of glycosylated flavonoids and other phenolic compounds in plant food materials based on an initial, standard analytical method. This approach applies the same analytical scheme (aqueous methanol extraction, reverse phase liquid chromatographic separation, and diode array and mass spectrometric detection) to every sample and standard. This standard approach allows the cross-comparison of compounds in samples, standards, and plant materials previously identified in the published literature.