Main Aglycones Research Articles

Identification of three types of O-glycosylated flavonoids in Dendrobium loddigesii, Dendrobium primulinum, Dendrobium crepidatum, Dendrobium porphyrochilum, and Dendrobium hancockii using mass spectrometry.

Flavonoids, representing the pharmacologically active ingredients, are found widely in Dendrobium species. The biodiversity of Dendrobium makes the identification of its varieties all the more complicated. Previous studies showed that C-glycosylated flavones and a few O-glycosylated flavonols could be used in the identification of various Dendrobium species. Accordingly, this study further explores the significance of the identification of various types of O-glycosylated flavonoids in Dendrobium species. High-performance liquid chromatography coupled with electrospray ionization multistage tandem mass spectrometry (HPLC-ESI-MSn ) was used to identify the chemical constituents in five types of Dendrobium: Dendrobium loddigesii, Dendrobium primulinum, Dendrobium crepidatum, Dendrobium porphyrochilum, and Dendrobium hancockii. A total of 41 O-glycosylated flavonoids and 3 C-glycosylated flavones were identified, among which O-glycosylated dihydroflavones were the main flavonoids in D. loddigesii and D. primulinum, O-Glycosylated flavonols were rich in both D. crepidatum and D. porphyrochilum characterized by the main aglycone, substituted sugars, and their structural characteristics, and O-glycosylated flavones were the main constituents in D. hancockii. In this study, three types of O-glycosylated flavonoids in the five Dendrobium species were determined to have certain significance. This also provides a reference for the identification of other O-glycosylated flavonoids in Chinese herbs.

Profiling of Biologically Active Metabolites of Spergula fallax L. Using High-resolution UPLC-QTOF-MS.

Medicinal plants are recognized to have a wide range of important biological activities, Spergula fallax L. is a well-known plant while phytochemical and biological activities screening of the species are rare. This study aims to evaluate the antioxidant, anticáncer, antimicrobial, and antiviral activities of the methanol extract (ME) of the aerial parts of Spergula fallax L. and its successive fractions; n-hexane (HF), ethyl acetate (EAF), and n-butanol (BF) fractions and identify their biologically active metabolites. Ultra-performance liquid chromatography (UPLC) coupled to quadrupole high-resolution time-of-flight mass spectrometry (QTOF-MS) was utilized to establish the metabolic profile of Sergula fallax L. Total phenol and flavonoids content were determined colorimetrically using Folin Ciocalteu and aluminum chloride reagents, respectively. 1,2-diphenyl-1-picrylhydrazyl (DPPH) was utilized for estimation of antioxidant activity, cytotoxic activity was determined on Hep-G2, HCT- 116, and MCF-7 cell lines, and agar diffusion method was used for screening of antimicrobial activity while cytopathic effect inhibition assay was utilized for antiviral assay. Twenty-eight metabolites were identified, flavonoids were predominated (26), it was characterized by the presence of four main aglycones (Apigenin, luteolin, quercetin and kaempferol) with their O and/or C-glycosides based on its MS fragments. ME and EAF significantly scavenged DPPH in a dose-dependent manner with IC50 16.99 and 18.74 μg.mL-1, respectively. Among the tested samples, only ME and EAF showed significant cytotoxic activity against the tested cell lines with IC50 ranging from 5.541- 9.509 μg.mL-1. All tested samples significantly inhibited the growth of the tested bacterial strains with inhibition zone diameters ranging from 11.2- 26.4 mm and showed a wide range of antiviral activity. Generally, S. fallax is potentially bioactive as evident by antioxidant, cytotoxic, antibacterial, and antiviral assays. These activities are correlated with its identified metabolites. The results proved that S. fallax has promising medicinal activities and would be examined in future clinical trials for herbal therapy.

Isolation, characterization and quantification of a pentacyclic triterpinoid compound ursolic acid in Scabiosa palaestina L. distributed in the north of Iraq

Ursolic acid (UA, 3 ?-hydroxy-urs-12-en-28-oic acid) are isomeric triterpenic acids. The high quantities of pentacyclic triterpenoids in Scabiosa species seems to be obvious and there is an evidence that most of pentacyclic triterpenoids that have been isolated are saponins. This is one of the most important characteristic of the genus Scabiosa, the main aglycones are ursolic acid and oleanolic acid. In the current study, isolation from the aerial part and roots of Scabiosa palaestina L. was performed using Preparative HPLC. Furthermore, detection and quantitation of ursolic acid was performed by high performance thin layer chromatography (HPTLC). The identification of isolated triterpenoid involves two methods including FT-IR coupled with LC-MS/MS that have been used for the simultaneous determination of the isolated UA. Quantitative analysis of Ursolic acid content in chloroform fractions revealed that both of the aerial parts and roots contain comparable concentration of 0.052 and 0.054 mg/ml respectively. The FT-IR and LC-MS/MS spectra of the isolated compound shows good agreement with those reported in literatures of Ursolic acid. Quantitative concentration of UA in chloroform fraction revealed that aerial parts and roots contain comparable concentrations and the spectral data for the isolated unknown were in good agreement with those reported in literature of UA.

Chemical composition and microencapsulation suitability of sumac (Rhus coriaria L.) fruit extract

Sumac (Rhus coriaria L.), a spice obtained by grinding whole sumac berries, is a complex natural product with a plethora of biological activities that can be favorably explored in nutraceutical and pharmaceutical fields. Sicilian sumac is herein chemically investigated by means of a combined NMR/HR MS-based profiling. A hydroalcoholic extract was prepared and its complexity unraveled following fractionation in an alcoholic and an aqueous fraction. The 1H-NMR spectrum of this latter fraction was dominated by the signals of gallic acid and its derivatives, whereas HR MS and HR MS/MS analyses highlighted the diversity in malic acid derivatives. Gallotannins and galloyl flavonol glycosides with quercetin and myricetin as the main aglycones were highly represented in the alcoholic fraction. To improve bioavailability of chemicals in sumac extract, the feasibility of a microencapsulation process by spray drying was investigated. In particular, the addition of maltodextrin, cyclodextrin and gum arabic as covering agents was evaluated. The tests were carried out at different temperatures and concentrations. The addition of maltodextrin was found to be suitable as a carrier for the spray drying of sumac extract, having the highest yields, always > 82%. The highest values of a* (red index) and Chroma were recorded with cyclodextrin and maltodextrin at the lowest concentrations and temperatures of spray drying (120 °C). The correlations between the characteristics of the studied microcapsules (yields, moisture, total and surface polyphenols and colour) have been represented by Principal Component Analysis (PCA).

Analysis of Intact Glycosidic Aroma Precursors in Grapes by High-Performance Liquid Chromatography with a Diode Array Detector.

Nowadays, the techniques for the analysis of glycosidic precursors in grapes involve changes in the glycoside structure or it is necessary the use of very expensive analytical techniques. In this study, we describe for the first time an approach to analyse intact glycosidic aroma precursors in grapes by high-performance liquid chromatography with a diode array detector (HPLC-DAD), a simple and cheap analytical technique that could be used in wineries. Briefly, the skin of Muscat of Alexandria grapes was extracted using a microwave and purified using solid-phase extraction combining Oasis MCX and LiChrolut EN cartridges. In total, 20 compounds were selected by HPLC-DAD at 195 nm and taking as a reference the spectrum of phenyl β-D-glucopyranoside, whose DAD spectrum showed a first shoulder from 190 to 230 nm and a second around 200–360 nm. After that, these glycosidic compounds were identified by High-performance liquid chromatography–quadrupole time-of-flight mass spectrometry (HPLC-qTOF-MS). Disaccharides hexose pentose were the most abundant group observed with respect to the sugars and monoterpendiols the main aglycones found.

Using power ultrasound to release glycosidically bound volatiles from orange juice: A new method

Acid hydrolysis and enzymatic hydrolysis are the main methods for releasing glycosidically bound volatiles (GBV). However, acid hydrolysis yields a strong pungent odor, and enzymatic hydrolysis is time consuming. In the present study, a new method, ultrasound hydrolysis, is reported to release GBV. This method is simple, environmentally friendly, fast and effective. Large differences were observed in the released aglycones and glycosyls between ultrasound and enzymatic hydrolysis of GBV. More types of aglycones were released under ultrasound than enzymatic hydrolysis. Alcohols and esters were the main aglycones under enzymatic hydrolysis, and terpenoids, esters and aldehydes were the main aglycones under ultrasound hydrolysis. The glycosyls released under ultrasound hydrolysis were mannose, glucose and sucrose, and those released under enzymatic hydrolysis were galactose and sucrose. The present study gives a new insight into a hydrolytic method for GBV by using ultrasound hydrolysis and can provide a reference method for fruit juice aromatization.

Characterization of phenolic profile and antioxidant activity of the leaves of the forgotten medicinal plant Balsamita major grown in Tuscany, Italy, during the growth cycle

Balsamita major (Asteraceae), known as costmary, is a medicinal plant rich of ethnobotanical interest in particular in Europe and Middle East, known and used since Greek and Roman times. The aim of the present study was to characterize the phenolic pattern of B. major leaves cultivated in Italy, and to measure the overall anti-radical (DPPH) and antioxidant activity (ORAC) during the growth cycle of the plant. Total polyphenols and total hydroxycinnamic acid derivatives were abundant in the leaves collected at all the growth stages, only decreasing in the flowering stage; flavonoids reached the highest content in the very early growth stage. Chlorogenic acid and 3,5-O-dicaffeoylquinic acid resulted to be the main phenolic constituents in all the extracts; their concentrations were highest at the late and early growth stages, respectively. Glycosilated flavonoids were found to be the abundant in all the extracts and quercetin resulted the main flavonoid aglycone, with the highest content in the very early growth stage. Both DPPH and ORAC tests registered good antiradical and antioxidant properties for all the extracts. Thus, B. major is worthy of further investigation, being an interesting source of antioxidant compounds, for pharmaceutical, nutraceutical and cosmetic purposes.

Anthocyanin Composition and Content in Rye Plants with Different Grain Color.

The color of grain in cereals is determined mainly by anthocyanin pigments. A large level of genetic diversity for anthocyanin content and composition in the grain of different species was observed. In rye, recessive mutations in six genes (vi1...vi6) lead to the absence of anthocyanins in all parts of the plant. Moreover, dominant genes of anthocyanin synthesis in aleurone (gene C) and pericarp (gene Vs) also affect the color of the grain. Reverse phase high-performance liquid chromatography and mass spectrometry were used to study anthocyanins in 24 rye samples. A lack of anthocyanins in the lines with yellow and brown grain was determined. Delphinidin rutinoside and cyanidin rutinoside were found in the green-seeded lines. Six samples with violet grains significantly varied in terms of anthocyanin composition and content. However, the main aglycone was cyanidin or peonidin in all of them. Monosaccharide glucose and disaccharide rutinose served as the glycoside units. Violet-seeded accession forms differ in the ratio of the main anthocyanins and the range of their acylated derivatives. The acyl groups were presented mainly by radicals of malonic and sinapic acids. For the colored forms, a profile of the revealed anthocyanins with the indication of their contents was given. The obtained results are discussed in connection to similar data in rice, barley, and wheat, which will provide a perspective for future investigations.

Variación en el contenido de clorofilas, carotenos y antocianos en agallas inducidas por Neolithus spp. (Hemiptera: Psyllidae) sobre Sapium haematospermum (Euphorbiaceae)

Agudelo, Ignacio; Marcelo Wagner; Rafael Ricco. 2017. “Variation in the content of chlorophylls, carotenoids and anthocyanins in galls induced by Neolithus spp (He- miptera: Psyllidae) in Sapium haematospermum (Euphorbiaceae)”. Lilloa 54 (2). Sapium hae- matospermum Mull. Arg. (Euphorbiaceae) is a tree native to South America and is usually infested by psyllids of the Neolithus genus, which induce the formation of galls in its leaves. The insect induces anatomical and biochemical changes that form a new structure with a particular tissue arrangement to protect the host. Photographs of red galls, green galls and mature fruit were obtained. Chlorophyll a and b, carotenoid pigments and anthocyanins were measured by spectrophotometric techniques. Also transversal cuts were performed in order to know the histological disposition of the anthocyanin compounds; the aglycone compound was characterized by chromatographic and spectrophotometric methods. Galls had a lower concentration of chlorophylls and carotenoids compared to healthy leaves. Anthocyanins were found in the external epidermis of red galls; this organ had the largest concentration of these pigments and the main aglycone was cyanidin. Green galls and healthy leaves didn’t have a detectable amount of these substances. Galls had a lower concentration of photosynthetic pigments; this is an indicator of a reduced photosynthesis typical of pho- toassimilates sinks. The anthocyanins are mainly cyanidin glycosides and are located in the external epidermis; this indicates and aposematic and/or an UV-protection function.

Quinoa seed coats as an expanding and sustainable source of bioactive compounds: An investigation of genotypic diversity in saponin profiles

Saponins (SAPs) are a diverse family of plant secondary metabolites and due to their biological activities, SAPs can be utilised as biopesticides and as therapeutic compounds. Given their widespread industrial use, a search for alternative sources of SAPs is a priority. Quinoa (Chenopodium quinoa Willd) is a valuable food source that is gaining importance worldwide for its nutritional and nutraceutical properties. SAPs from quinoa seed coats could represent a new sustainable source to obtain these compounds in high quantities due to the increasing production and worldwide expansion of the crop. This research aims to characterise saponins of seed coat waste products from six different quinoa varieties for their potential use as a saponin source. Gas chromatography (GC)- and Liquid chromatography (LC)- with mass spectrometry (MS) were applied for qualitative and relative quantitative analysis of saponins. GC–MS led to the identification of three main aglycones, oleanolic acid (Ole), hederagenin (Hed), and a phytolaccagenic acid (Phy), while LC–MS enabled characterization of 24 SAPs with varying sugar moieties. Hed was the most abundant aglycone, followed by Phy and Oledepending on the genotype. Saponin distribution and relative abundances are discussed in the light of genotype provenance and agronomic features. Improved knowledge on the phytochemicals present in quinoa varieties might help in finding valuable and sustainable uses for quinoa SAPs in agroindustry as biopesticides as well as in the production of food and pharmaceuticals.

In vitro Activities of Pfaffia glomerata Root Extract, Its Hydrolyzed Fractions and Pfaffic Acid Against Trypanosoma cruzi Trypomastigotes.

This article reports on the in vitro activity of the hydroalcoholic extract of Pfaffia glomerata roots, its hydrolyzed fractions, and pfaffic acid against Trypanosoma cruzi. The hydroalcoholic extract obtained from dried, milled P. glomerata roots was submitted to acid hydrolysis followed by partition with CHCl3 . The concentrated CHCl3 fraction was suspended in MeOH/H2 O and partitioned with hexane (F1), CHCl3 (F2), and AcOEt (F3), in this sequence. The trypanocidal activity of the hydrolyzed extract and its fractions was evaluated in vitro. The hydroalcoholic extract displayed low activity, but fraction F1 was active against trypomastigotes of the Y strain of T. cruzi, with IC50 = 47.89 μg/ml. The steroids campesterol (7.7%), stigmasterol (18.7%), β-sitosterol (16.8%), Δ7 -stigmastenol (4.6%), and Δ7 -spinasterol (7.5%) were the major constituents of F1, along with fatty acid esters (7.6%) and eight aliphatic hydrocarbons (30.1%). Fractions F2 and F3 exhibited moderate activity, and pfaffic acid, one of the main chemical constituents of these fractions, displayed IC50 = 44.78 μm (21.06 μg/ml). On the other hand, the hydroalcoholic extract of P. glomerata roots, which is rich in pfaffosides, was inactive. Therefore, the main aglycone of pfaffosides, pfaffic acid, is much more active against trypomastigotes of the Y strain of T. cruzi than its corresponding glycosides and should be further investigated.

Ruscus Genus: A Rich Source of Bioactive Steroidal Saponins.

The genus Ruscus (Asparagaceae family) is native to the Mediterranean, Southern and Western Europe and is represented by perennial, rhizomatous, and evergreen shrubs. Among the approximately seven species spread throughout Europe up to Iran, Ruscus aculeatus L. (butcher's broom) is the most widely distributed and appreciated. This review provides an overview of the traditional use of Ruscus spp., the current knowledge of the chemistry of this genus, and the pharmacological studies carried out on Ruscus spp. extracts. The underground parts of Ruscus plants are a source of steroidal saponins that can be classified into two structural classes: the hexacyclic spirostanol saponins and the pentacyclic furostanol saponins. The main aglycones are ruscogenin and neoruscogenin. From the pharmacological point of view, the most studied Ruscus species is undoubtedly R.aculeatus, a very ancient phlebotherapeutic agent. Pharmacological investigations since the discovery of the vasoconstrictive and venotonic properties of ruscogenin and neoruscogenin in the underground parts of R.aculeatus are discussed. Preparations based on Ruscus species are currently used for the treatment of chronic venous insufficiency, varicose veins, haemorrhoids, and orthostatic hypotension. Finally, analytical techniques for the quality control of R.aculeatus extracts are reported.

Protective effect of a hydrogel containing Achyrocline satureioides extract-loaded nanoemulsion against UV-induced skin damage

Achyrocline satureioides is a medicinal plant widely used in South America that exhibits a well-documented antioxidant activity. Such activity has been related to their main aglycone flavonoids quercetin, luteolin, and 3-O-methylquercetin (3MQ). This study addresses the development of antioxidant hydrogels containing an A. satureioides extract-loaded nanoemulsions aimed at topical application. The systems investigated were A. satureioides extract-loaded nanoemulsions (ASNE) obtained by spontaneous emulsification procedure formulated in semisolid hydrogels composed of Carbopol® Ultrez 20 (HASNE). Hydrogels exhibit a non-Newtonian pseudoplastic behavior. A higher release of 3MQ from ASNE (3.61μg/cm2/h) was observed when compared with HASNE (2.83μg/cm2/h). Different parameters that may have an influence on the retention of flavonoids into the skin were investigated by using a Franz-type diffusion cells. Indeed, the amount of formulation applied on donor compartment was found to play a crucial role. At the optimized conditions, retention of approximately 2μg/cm2 of flavonoids was detected into the skin. A higher retention of 3MQ was detected (approximately 1.0μg/cm2) in comparison with the other flavonoids. Finally, a protection the porcine ear skin by formulations, against oxidative stress generated by UVA/UVB light was demonstrated by means of TBARS, protein carbonylation, and protein thiol content assays. The overall results showed the potential of the formulations developed in this study for the prevention of oxidative stress on the skin.

Chemical Profile, Antioxidant and Antibacterial Activities of Achillea moschata Wulfen, an Endemic Species from the Alps.

Aerial parts of Achillea moschata Wulfen (Asteraceae) growing wild in the Italian Rhaetian Alps were investigated to describe, for the first time, their phenolic content, as well as to characterize the essential oil. Inspection of the metabolic profile combining HPLC-DAD and ESI-MS/MS data showed that the methanol extract contained glycosylated flavonoids with luteolin and apigenin as the main aglycones. Among them, the major compound was 7-O-glucosyl apigenin. Caffeoyl derivates were other phenolics identified. The essential oil obtained by steam distillation and investigated by GC/FID and GC/MS showed camphor, 1,8-cineole, and bornylacetate as the main constituents. The antioxidant capacity of three different extracts with increasing polarity and of the essential oil was evaluated by employing ABTS·+ and DPPH· radical scavenging assays. The methanolic extract was the only significantly effective sample against both synthetic radicals. All samples were also tested against Gram-positive (Bacillus cereus, Enterococcus faecalis, Staphylococcus aureus) and Gram-negative (Escherichia coli, Proteus mirabilis, Pseudomonas aeruginosa) bacterial species using the disk diffusion assay. The non-polar extracts (dichloromethane and petroleum ether) and the essential oil possessed a broad spectrum of antimicrobial activity expressed according to inhibition zone diameter (8–24 mm).

Extraction of dyes from Delphinium Zalil flowers and dyeing silk yarns

Delphinium Zalil from the family Ranunculaceae grows naturally in mountainous area of northeast of Iran. It has beautiful yellow flowers which contain flavonoids. In this study, the flowers of D. Zalil were collected, dried, powdered, and extracted with different solvent systems. Quercetin is identified as the main aglycone responsible for the color in these flowers. The flowers were then used for dyeing silk yarns. The color strength values were used to optimize the dyeing process. Pre-mordanting was proved to increase the dye absorption which may lead to an optimum usage of mordant. This would certainly be of special interest to environmentalists. Dyed silk yarns presented good light fastness compared to Blue Scale.

Identification of Icaritin Metabolites in Rats by LC-MS/MS

ObjectiveIcaritin is the main aglycone and also active intestinal metabolite of prenylflavonoids from the Chinese materia medica Epimedii Herba. Modern pharmacological studies have demonstrated that icaritin has a wide range of biological activities. However, its metabolites and biotransformation pathways have not yet been comprehensively investigated. The present study aims to identify icaritin metabolites in rats by using a sensitive and effective LC-MS/MS method. MethodsThe plasma and urine samples of rats were collected before (blank) and after oral administration of icaritin, and subjected to liquid-liquid extraction with ethyl acetate. The full-scan LC-MS chromatograms of the plasma and urine samples were compared with those of blank samples to detect the possible metabolites, which were later detected by their product ion spectra. ResultsA total of 23 metabolites were identified, and conjugated icaritins produced by glucuronidation, glycosylation, and sulfation were its major metabolites. Minor demethylation, hydrogenation, and oxidation metabolites were also found. ConclusionPhase II metabolism is the main metabolic pathway of icaritin.

Phytochemical analysis of Passiflora loefgrenii Vitta, a rich source of luteolin-derived flavonoids with antioxidant properties.

The paper describes the flavonoid composition of the aerial parts (young leaves, YL; adult leaves, AL; stems, ST) of Passiflora loefgrenii Vitta, a rare species native to Brazil, where it is traditionally used as food. Antioxidant potential has also been evaluated. To the best of our knowledge, no phytochemical and biological study on this species has been reported previously. Compositional data have been acquired combining HPLC-diode array detector (DAD) and Electrospary ionization-tandem mass spectrometry (ESI-MS/MS) analyses. Antioxidant activity has been evaluated by the 2,2'-di-phenyl-1-picrylhydrazyl method. Glycosylated flavones, with luteolin as the main aglycone, can be regarded as biomarkers for this drug. Qualitative composition of the extracts from YL, AL and ST was similar. The bulk of the constituents was made up by 8-C-ß-glucosyl luteolin (orientin), 7-O-α-rhamnosyl-6-C-ß-glucosyl luteolin and 6-C-α-rhamnosyl luteolin, which totally amounted to 16.57 (73%), 10.77 (74%) and 5.07 (77%) μg/mg in YL, AL and ST, respectively. P. loefgrenii showed a good antioxidant activity (IC50 of 350 μg/ml), higher than generally reported for other passifloras. P. loefgrenii, rich in luteolin glycosides, can be regarded as a good candidate to be explored for therapeutic properties other than the sedative one since it represents a rich source of valuable flavonoids with antioxidant potential.

Triterpene saponins with anti-inflammatory activity from the stems of Entada phaseoloides

The phytochemical investigation of the ethanol extract from the stems of Entada phaseoloides (L.) Merr (also called “Guo Gang Long”) led to the isolation of eleven triterpene saponins (1–11). Their structures were elucidated by extensive spectroscopic methods including 1D- (1H and 13C) and 2D-NMR (1H–1H COSY, HSQC, HMBC, HSQC-TOCSY and ROESY) experiments as well as ESIMS analysis and hydrolysis. These saponins comprised entagenic acid as the main aglycon, saccharide moieties at C-3 and C-28, and esterification of C-2 or C-3 hydroxyl group of the terminal β-d-glucopyranose unit with a monoterpenic acid. To further explain the clinical applications of “Guo Gang Long” for its anti-inflammatory effect, the inhibitory activities on the production of NO of the saponins and the related aglycon, entagenic acid (12), were evaluated in vitro. The compounds containing a free hydroxyl at C-3 of aglycon (1 and 4) and entagenic acid showed significant activities against NO production in lipopolysaccharide-stimulated mouse macrophage RAW264.7 cells with IC50 values of 25.08, 20.13 and 23.48μM, respectively. And the three compounds could also inhibit the release of pro-inflammatory cytokines, such as TNF-α, IL-1β, IL-6 and IL-8.

Characterization of flavonoid glycosides from fenugreek (Trigonella foenum-graecum) crude seeds by HPLC-DAD-ESI/MS analysis.

Fenugreek (Trigonella foenum-graecum) is a medicinal plant which is widely used for its pharmacological properties. In this study the phenolic composition of fenugreek crude seeds originating from Morocco has been investigated. Extraction was performed from defatted seeds by a hydromethanolic solution using an Accelerated Solvent Extractor. HPLC technique coupled to negative ion electrospray ionization mass spectrometry and diode array detection was employed to identify the polyphenol in the obtained extract. The obtained results allowed the detection of 32 phenolic compounds among which various flavonoid glycosides and phenolic acids have been tentatively identified on the basis of their UV and MS spectra, and comparisons with standards when available, as well as with literature data. A systematic study of the obtained MS spectra and the observed fragmentation showed that most of the identified compounds were acylated and non-acylated flavonoids with apigenin, luteolin and kaempferol as aglycons. Hydroxycinnamic acids mostly dominated by caffeic acid derivatives were also detected. The quantitative analysis of the identified compounds showed that the phenolic composition of the studied crude fenugreek seeds was predominantly acylated and non-acylated flavone derivatives with apigenin as the main aglycon.

High-performance liquid chromatography LTQ-Orbitrap mass spectrometry method for tomatidine and non-target metabolites quantification in organic and normal tomatoes

Tomatoes, members of the Solanaceae plant family, produce biologically active secondary metabolites, including glycoalkaloids and aglycons, which may have both adverse and beneficial biological effects. A new liquid chromatography method that utilized LTQ-Orbitrap MS was developed for the analysis of tomatidine, the main aglycon in tomatoes. Recoveries of tomatidine were >98.3% with the relative standard deviations (RSDs) below 6.1%. The limit of detection (LODs) was 0.0003 mg kg−1. The limit of quantitation (LOQs) is 0.001 mg kg−1. The linear range was between with 0.0025 and 1 mg kg−1 with an excellent correlation coefficient (R2) equal to 0.9990. Various tomato samples were analyzed and the level of tomatidine in the 11 samples analysed was higher in normal respect to organic tomatoes. The capability of the set-up Full Scan LTQ-Orbitrap MS method allowed us to quantified two non-target analytes. The m/z 1032 was identified as dehydrotomatine, confirmed through accurate mass studies (mass error in ppm equal to 1.5017) meanwhile m/z 902 as (Glc)2–Gal-Tomatidine (β1-Tomatine) (mass error in ppm equal to 2.0719).