Direct identification of phenolic constituents in Boldo Folium (Peumus boldus Mol.) infusions by high-performance liquid chromatography with diode array detection and electrospray ionization tandem mass spectrometry

Antioxidant capacity and HPLC-DAD-MS profiling of Chilean peumo (Cryptocarya alba) fruits and comparison with German peumo (Crataegus monogyna) from southern Chile

Liquid chromatography (LC) coupled with UV detection and electrospray ionization (ESI) tandem mass spectrometry (MS/MS) was used for the generation of chemical fingerprints and the identification of phenolic compounds in peumo fruits and aerial parts from southern Chile. Thirty three compounds (19 of these detected in C. alba and 23 in C. monogyna) were identified, mainly flavonoid glycosides, phenolic acids, anthocyanins and flavonoid aglycons. Total phenolic content and total flavonoid content was measured for both species, and were higher in the extracts from C. monogyna fruits and aerial parts than extracts from C. alba. The fruits of Cryptocarya alba (Chilean peumo) presented high antioxidant capacity (9.12 ± 0.01 mg/mL in the DPPH assay), but was three times lower to that of Crataegus monogyna (German peumo) (3.61 ± 0.01 mg/mL in the DPPH assay).

The Passiflora tripartita (Banana Passion) fruit: a source of bioactive flavonoid C-glycosides isolated by HSCCC and characterized by HPLC–DAD–ESI/MS/MS

The banana passion fruit (Passiflora tripartita Breiter, Passifloraceae) known as “tumbo” is very appreciated in tropical and subtropical countries of South America. Methanolic extracts from peel and the fruit juice of P. tripartita growing in Chile were analyzed for antioxidant capacity as well as for flavonoid and phenolic content. A chromatographic method was developed for the rapid identification of the main phenolics in the samples by HPLC-DAD and HPLC-MS. The fast fingerprint analysis allowed the detection of eighteen flavonoid C-glycosides and four flavonoid O-glycoside derivatives which were characterized by UV spectra and ESI-MS-MS analysis. Several of the C-glycosides detected are structurally related to the orientin derivative 4′-methoxy-luteolin-8-C-(6″acetyl)-β-D-glucopyranoside (31), fully elucidated by spectroscopic methods. The antioxidant derivative 31 along with schaftoside, vicenin II, orientin and vitexin were isolated from the fruit extract by high-speed countercurrent chromatography (HSCCC). A suitable method for the preparative isolation of flavonol C-glycosides from “tumbo” extracts by HSCCC is reported. The pulp of the fruits showed good antioxidant capacity (12.89 ± 0.02 μg/mL in the DPPH assay). The peel presented the highest content of flavonoids (56.03 ± 4.34 mg quercetin/100 g dry weight) which is related to the highest antioxidant power (10.41 ± 0.01 μg/mL in the DPPH assay).

Fast HPLC-DAD quantification of nine polyphenols in honey by using second-order calibration method based on trilinear decomposition algorithm

This paper describes the use of second-order calibration for development of HPLC-DAD method to quantify nine polyphenols in five kinds of honey samples. The sample treatment procedure was simplified effectively relative to the traditional ways. Baselines drift was also overcome by means of regarding the drift as additional factor(s) as well as the analytes of interest in the mathematical model. The contents of polyphenols obtained by the alternating trilinear decomposition (ATLD) method have been successfully used to distinguish different types of honey. This method shows good linearity (r>0.99), rapidity (t<7.60 min) and accuracy, which may be extremely promising as an excellent routine strategy for identification and quantification of polyphenols in the complex matrices.

LC-MS-based chemotaxonomic classification of wild-type Lespedeza sp. and its correlation with genotype

In this study, 39 specimens belonging to Lespedeza species (Lespedeza cyrtobotrya, L. bicolor, L. maximowiczii, and Lespedeza cuneata) (Leguminosae) were classified phenotypically and genotypically. We constructed a phylogenetic tree based on the combined nrDNA (internal transcribed spacer; ITS) and cpDNA (trnL-trnF) sequences with the aim of classifying the genotypes. Samples were mainly divided into three genotypes. Samples of L. cyrtobotrya and L. bicolor were mixed in a single branch, whereas samples of L. maximowiczii and L. cuneata were clustered within species, respectively. We performed a liquid chromatography-electrospray ionization-mass spectrometry-based metabolite profiling analysis to classify the phenotypes. Multivariate statistical analyses such as principal component analysis (PCA) and hierarchical clustering analysis (HCA) were used for the clustering pattern analysis and distance analysis between species, respectively. According to the PCA and HCA results, leaves were classified into four phenotypes according to species. In both the genetic and chemotaxonomic classification methods, the distance between L. cyrtobotrya and L. bicolor was the closest between species, and L. cuneata was the farthest away from the other three species. Additionally, orthogonal partial least squares-discriminant analysis was employed to identify significantly different phytochemicals between species. We classified L. cyrtobotrya and L. bicolor by identifying significantly different phytochemicals. Interestingly, leaves and stems showed different phenotypic classifications based on the chemotaxonomic classification. Stem samples of the other three species were mixed regardless of species, whereas L. cyrtobotrya stem samples were clustered within species. The phenotypic classification of leaves coincided more with the genotypic classification than that of stems. Key message We classified four wild-type Lespedeza sp. by analyzing the combined nrDNA (ITS) and cpDNA (trnL-trnF) sequences. We also classified leaves and stems of Lespedeza sp. by applying liquid chromatography-mass spectroscopy-based metabolite profiling.

Phenolic constituents of the Chilean herbal tea Fabiana imbricata R. et P

"Pichi" or "pichi romero" (Fabiana imbricata R. et. P., Solanaceae) is a Chilean plant used as a tea in the Andean regions of Chile and Argentina. A very simple and direct method was developed for the qualitative analysis of polyphenols in the tea by high-performance liquid chromatography (HPLC) with diode array detection and electrospray ionization tandem mass spectrometry. The phenolic constituents identified in the teas were chlorogenic acid (3-O-caffeoylquinic acid), p-hydroxyacetophenone, scopoletin and quercetin derivatives. The glycosides were mainly glucosides from p-hydroxyacetophenone and scopoletin while di- and tri-glycosides from quercetin were the main flavonoids. The content of the main phenolic compounds in the teas (g/100 g lyophilized infusion) was 0.8-1.9 % for scopoletin, 0.4-6.2 % for p-hydroxyacetophenone and 2.1-4.3 % for rutin, respectively. The health-promoting properties reported for this herbal tea can be associated with the presence of several phenolics with known antioxidant, diuretic and antiinflammatory activity.

Characterization of phenolic compounds and antinociceptive activity of Sempervivum tectorum L. leaf juice

Sempervivum tectorum L. (houseleek) leaf juice has been known as a traditional herbal remedy. The aim of the present study was the chemical characterization of its phenolic compounds and to develop quantitation methods for its main flavonol glycoside, as well as to evaluate its antinociceptive activity. Lyophilized houseleek leaf juice was studied by HPLC-DAD coupled to electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) to identify flavonol glycosides, hydroxy-benzoic and hydroxy-cinnamic acids. Ten flavonol glycosides and sixteen phenolic acid compounds were identified or tentatively characterized. Structure of the main flavonol compound was identified by nuclear magnetic resonance spectroscopy. Three characteristic kaempferol glycosides were isolated and determined by LC-ESI-MS/MS with external calibration method, using the isolated compounds as standard. The main flavonol glycoside was also determined by HPLC-DAD. Validated HPLC-DAD and LC-ESI-MS/MS methods were developed to quantify kaempferol-3-O-rhamnosyl-glucoside-7-O-rhamnoside and two other kaempferol glycosides. Antinociceptive activity of houseleek leaf juice was investigated by writhing test of mice. Sempervivum extract significantly reduced pain in the mouse writhing test.

Rosmarinic acid content in antidiabetic aqueous extract of Ocimum canum sims grown in Ghana

Rosmarinic acid (RA) is an important antioxidant polyphenol that is found in a variety of spices and herbs, including Ocimum canum Sims (locally called eme or akokobesa in Ghana). Aqueous extracts from the leaves of O. canum are used as an antidiabetic herbal medicine in Ghana. Analytical thin-layer chromatography was used to examine the composition of the polyphenols in leaf extracts. The polyphenol content in the aqueous and methanol extracts from the leaf, as determined by the Folin-Ciocalteu method, were 314 and 315 mg gallic acid equivalent/g leaf sample, respectively. The total flavonoid concentration as determined by the aluminum(III) chloride method was 135 mg catechin equivalent/g leaf sample. High-performance liquid chromatography coupled to an electrospray Quadrupole time-of-flight mass spectrometer was also used to determine the polyphenol fingerprint profile in the leaf extracts of O. canum. Although the average RA concentration in the O. canum leaf extracts from Ghana was 1.69 mg/g dry weight (reported values range from 0.01 to 99.62 mg/g dry weight), this polyphenol was still a prominent peak in addition to caffeic acid derivatives.

Acetylcholinesterase inhibition, antioxidant activity and toxicity of Peumus boldus water extracts on HeLa and Caco-2 cell lines

This work aimed to study the inhibition on acetylcholinesterase activity (AChE), the antioxidant activity and the toxicity towards Caco-2 and HeLa cells of aqueous extracts of Peumus Boldus. An IC(50) value of 0.93 mg/mL, for AChE inhibition, and EC(50) of 18.7 μg/mL, for the antioxidant activity, was determined. This activity can be attributed to glycosylated flavonoid derivatives detected, which were the main compounds, although boldine and other aporphine derivatives were also present. No changes in the chemical composition or the biochemical activities were found after gastrointestinal digestion. Toxicity of P. boldus decoction gave an IC(50) value 0.66 mg/mL for HeLa cells, which caused significant changes in the cell proteome profile.

Authentication of Senecio scandens and S. vulgaris based on the comprehensive secondary metabolic patterns gained by UPLC-DAD/ESI-MS

A secondary metabolic pattern using ultra-performance liquid chromatography (UPLC)-DAD/ESI-MS was constructed to gain chemical information for authentication of Senecio scandens (SS) and Senecio vulgaris (SV), the two representative species containing hepatotoxic pyrrolizidine alkaloids (HPAs). The metabolic pattern showed three groups of bioactive constituents: phenolic/aromatic acids, flavonoid glycosides and the HPAs. 47 peaks were identified including 19 phenolic/aromatic acids, 10 flavonoid glycosides and 18 PAs by direct comparison with the available reference compounds or deduced from the UV absorption and their ESI-MS fragmentation patterns. The two species could be authenticated diagnostically by their metabolic profiling of the three chromatographic fingerprints. Although both SS and SV contain PAs as the characteristic constituents, only 2 PAs, adonifoline and adonifoline N-oxide were detected in SS, while other 16 PAs were detected in SV, including the highly toxic senecionine, retrorsine, seneciphylline and their corresponding N-oxides. The concentration of PAs in SV is also higher than that in SS. The number and concentration of the phenolic compounds in SS were higher than in SV. Jacaranone derivatives were only detected in SS and jacaranone ethyl ester was detected as the predominant constituent. In the fingerprint of the n-butanol extracts, 10 quercetin and kaempferol glycosides derivatives were detected. 9 were found in SS and only 2 in SV. PAs, jacaranone derivatives and flavonoid glycosides can serve as the metabolic markers to distinguish the Senecio plants from each other, and provide evidence for their clinical application in the consideration of safety and efficacy.

Herbicidal activity of Peumus boldus and Drimys winterii essential oils from Chile

The essential oil composition of Peumus boldus and Drimys winterii was analyzed by means of capillary GC-FID and GC-MS. More than 96% of the total oil components (43 and 54 compounds, respectively) were identified, with ascaridole (51.17 ± 9.51), p-cymene (16.31 ± 2.52) and 1,8-cineole (14.45 ± 2.99) as the main compounds in P. boldus and γ-eudesmol (21.65 ± 0.41), followed of elemol (12.03 ± 0.34) and terpinen-4-ol (11.56 ± 1.06) in D. winterii. The herbicidal activity was tested against Amaranthus hybridus and Portulaca oleracea. P. boldus essential oil was the most phytotoxic against both weeds, inhibiting seed germination and seedling growth at all concentrations assayed (0.125–1 µL/mL). D. winterii essential oil did not show any effect on A. hybridus germination and only affected P. oleracea germination at the highest concentration. The results suggest the possible use of the essential oil from P. boldus as a natural herbicide.