Rapid Chemical Profiling of Filipendula ulmaria Using CPC Fractionation, 2-D Mapping of 13C NMR Data, and High-Resolution LC-MS

Filipendula ulmaria, commonly known as meadowsweet, is a wild herbaceous flowering plant that is widely distributed in Europe. A range of salicylic acid derivatives and flavonol glycosides have been previously associated with the antirheumatic and diuretic properties of F. ulmaria. In the present work, a hydroalcoholic extract from F. ulmaria aerial parts was extensively profiled using an efficient NMR-based dereplication strategy. The approach involves the fractionation of the crude extract by centrifugal partition chromatography (CPC), 13C NMR analysis of the fractions, 2D-cluster mapping of the entire NMR dataset, and, finally, structure elucidation using a natural metabolite database, validated by 2D NMR data interpretation and liquid chromatography coupled with mass spectrometry. The chemodiversity of the aerial parts was extensive, with 28 compounds unambiguously identified, spanning various biosynthetic classes. The F. ulmaria extract and CPC fractions were screened for their potential to enhance skin epidermal barrier function and skin renewal properties using in vitro assays performed on Normal Human Epidermal Keratinocytes. Fractions containing quercetin, kaempferol glycosides, ursolic acid, pomolic acid, naringenin, β-sitosterol, and Tellimagrandins I and II were found to upregulate genes related to skin barrier function, epidermal renewal, and stress responses. This research is significant as it could provide a natural solution for improving hydration and skin renewal properties.

Non-destructive, reverse iontophoretic extraction of phytochemicals from Mangifera indica, Centella asiatica, Punica granatum, and Citrus sinensis

For the commercial-scale isolation of phytochemicals, a suitable plant biomass source (including species, origin, growing season, etc.) must be identified, and frequent analytical verification is required to ensure that the phytochemicals are present at predefined minimum threshold concentrations. While the latter are typically assessed in the laboratory, a more efficient and less resource-intensive approach would involve non-destructive and environmentally friendly measurements in situ. Reverse iontophoretic (RI) sampling offers a potential solution to this challenge.

OBJECTIVE

We aimed to demonstrate the non-destructive, RI sampling of phytochemicals of interest from biomass from four different sources.

MATERIALS AND METHODS

RI experiments were performed in side-by-side diffusion cells using a current density of 0.5 mA/cm² , for a predetermined time in a defined pH environment, using (1) fresh leaves from Mangifera indica and Centella asiatica and (2) isolated peel from Punica granatum and Citrus sinensis.

RESULTS

Mangiferin, madecassoside, punicalagin, ellagic acid, and hesperidin were extracted from the different biomasses by RI. The amounts extracted ranged from 0.03 mg/100 mg of biomass for the cathodal extraction of madecassoside to 0.63 mg/100 mg of biomass for the anodal extraction of punicalagin. A linear relationship (r²  = 0.73) between the RI-extracted quantities of punicalagin and those determined using conventional methods was demonstrated.

CONCLUSION

The non-destructive, in situ measurement of phytochemical levels by RI represents a feasible approach for timing the harvesting process.

Comprehensive characterization of naturally occurring antioxidants from the twigs of mulberry (Morus alba) using on-line high-performance liquid chromatography coupled with chemical detection and high-resolution mass spectrometry

INTRODUCTION

The mulberry tree (Morus alba L.) is a prolific source of biologically active compounds. There is considerable growing interest in probing M. alba twigs as a source of disruptive antioxidant lead candidates for cosmetic skin care product development.

OBJECTIVE

An integrated approach using high-performance liquid chromatography (HPLC) coupled with either chemical detection (CD) or high-resolution mass spectrometry (HRMS) was applied to the hydroalcoholic extract of M. alba to detect and identify lead antioxidant compounds, respectively.

MATERIAL AND METHODS

The twigs were weighed, powdered and homogenized using a mill and the extract was prepared using 70% aqueous ethanol. The antioxidant metabolites were detected with HPLC coupled with CD (based on the ORAC assay) and their structural identification was carried out using a Q-Exactive Orbitrap MS instrument.

RESULTS

Using this approach, 13 peaks were detected as overall contributors to the antioxidant activity of M. alba, i.e. mulberrosides (A & E), oxyresveratrol & its derivatives, moracin & its derivatives and a dihydroxy-octadecadienoic acid, which together accounted for >90% of the antioxidant activity, highlighting the effectiveness of the integrated approach based on HPLC-CD and HPLC-HRMS. Additionally, a (3,4-dimethoxyphenyl-1-O-β-D-apiofuranosyl-(1″ → 6')-O-β-D-glucopyranoside was also discovered for the first time from the twig extract and is presented here.

CONCLUSION

To our knowledge, this is the first report from M. alba twigs using HPLC-CD and HPLC-HRMS that identifies key compounds responsible for the antioxidant property of this native Chinese medicinal plant.

Longevity effect of a polysaccharide from Chlorophytum borivilianum on Caenorhabditis elegans and Saccharomyces cerevisiae

The traditional Indian medicine, Ayurveda, provides insights and practical solutions towards a healthy life style. Rasayana is a branch of Ayurveda known for preserving and promoting health, enhancing the quality of life and delaying the aging process. In the traditional knowledge, the Rasayana herb, Chlorophytum borivilianum (C. borivilanum) is regarded as a general health promoting tonic that delays aging and increases lifespan, cognitive function and physical strength. Aging is a complex and multifactorial physiological phenomenon that manifests itself over a wide range of biological systems, tissues, and functions. Longevity is an obvious marker of physiological aging. Simple model systems such as the single-cell budding yeast Saccharomyces cerevisiae (S. cerevisiae) and the nematode, Caenorhabditis elegans (C. elegans) are widely used to study the aging process and longevity. Here, we show that a polysaccharide fraction obtained from C. borivilianum increases the lifespan of S. cerevisiae and C. elegans, using an automated screening platform (Chronoscreen^TM). Chemical analysis of this extract revealed a low molecular weight polysaccharide of 1000 Da, predominantly comprising Glu1→6Glu linkage. This polysaccharide showed significant dose-dependent extension of the median lifespan of S. cerevisiae by up to 41% and of the median lifespan of C. elegans by up to 10%. Taking cue from these results and the traditionally described benefits of Rasayanas on skin rejuvenation, we tested in vitro the polysaccharide for potential skin benefits. In a keratinocyte culture, we observed that this polysaccharide increased cell proliferation significantly, and induced synthesis of hyaluronic acid (HA), a well-known extracellular matrix component. Furthermore, when added to culture medium of human reconstructed epidermis, we observed an enhanced production of epidermal markers, e.g. CD44 and HA that are otherwise diminished in aged skin. Together, these results suggest that in addition to life-span extension of S. cerevisiae and C. elegans, a polysaccharide from the Rasayana herb, C. borivilianum may have beneficial effects on skin aging parameters.

Rare Prenylated Isoflavones from Tephrosia calophylla

Chemical re-examination of the roots of T. calophylla led to the isolation of four isoflavones, namely 2′,4′,5-trihydroxy-6,7-(2″,2″-dimethylchromene)-8-γ,γ-dimethylallylisoflavone (1a, auriculatin), 2′,5-dihydroxy-6,7-(2″,2″-dimethylchromene)-4′-γ,γ-dimethylallyloxyisoflavone (2a, isoauriculatin), 3′,4′,5-trihy-droxy-6,7-(2″,2″-dimethylchromene)-8-γ,γ-dimethylallylisoflavone (1b, auriculasin), and 3′,5-dihydroxy-6,7-(2″,2″-dimethylchromene)-4′-γ,γ-dimethylallyl-oxyisoflavone (2b, isoauriculasin). Auriculasin and isoauriculasin are reported for the first time with full NMR assignments. All metabolites were fully characterized by 1D and 2D NMR techniques including COSY, HSQC, HMBC experiments, mass spectra and in part on the basis of X-ray diffraction. Accurate ‘invariom’ refinements with aspherical scattering factors were carried out for 1a, 1b and 2a.

Rare prenylated isoflavones from Tephrosia calophylla

Chemical re-examination of the roots of T. calophylla led to the isolation of four isoflavones, namely 2',4',5-trihydroxy-6,7-(2",2"-dimethylchromene)-8-gamma,gamma-dimethylallylisoflavone (1a, auriculatin), 2',5-dihydroxy-6,7-(2",2"-dimethylchromene)-4'-gamma,gamma-dimethylallyloxyisoflavone (2a, isoauriculatin), 3',4',5-trihydroxy-6,7-(2",2"-dimethylchromene)-8-gamma,gamma-dimethylallylisoflavone (1b, auriculasin), and 3',5-dihydroxy-6,7-(2",2"-dimethylchromene)-4'-gamma,gamma-dimethylallyl-oxyisoflavone (2b, isoauriculasin). Auriculasin and isoauriculasin are reported for the first time with full NMR assignments. All metabolites were fully characterized by 1D and 2D NMR techniques including COSY, HSQC, HMBC experiments, mass spectra and in part on the basis of X-ray diffraction. Accurate 'invariom' refinements with aspherical scattering factors were carried out for 1a, 1b and 2a.

Polyphenolic fraction of Pilea microphylla (L.) protects Chinese hamster lung fibroblasts against γ-radiation-induced cytotoxicity and genotoxicity

Present study was designed to compare cytoprotective and antigenotoxic activity of the polyphenolic fraction of Pilea microphylla (PM1) with that of its active polyphenolic constituents against γ-radiation in V79 cells. PM1 was standardized with respect to the polyphenols present by RP-HPLC. It was evaluated for its free radical scavenging potential using Fenton reaction-induced DNA damage and lipid peroxidation. Further, PM1 was subjected against γ-radiation-induced cytotoxicity and genotoxicity in V79 cells. PM1 significantly reduced free radical-mediated calf thymus DNA damage and lipid peroxidation. Among the concentrations tested (12.5, 25 and 50 μg/ml) for radioprotection, PM1 at 25 μg/ml exhibited maximum protection. Further, when compared with constituent polyphenols viz., rutin, quercetin and chlorogenic acid (concentrations equivalent to that present in PM1-25 μg/ml), a combination of polyphenols was found most effective in preventing γ-radiation-induced cytotoxicity and genotoxicity. To conclude, radioprotection is possibly a synergistic effect of the phytochemicals present in the herbal extract, rather than any single component.

A phenethyl bromo ester from Citharexylum fruticosum

A new compound, (2S)-p-hydroxyphenethyl 2-bromo-2-methyldodeconate (1) and 7,3'-dimethoxy-5,4'-dihydroxy flavone, together with lupeol and stigmasterol were isolated from the stem bark of Citharexylum fruticosum (Verbenaceae). The structures of the compounds were established on the basis of the interpretation of NMR (1H, 13C, COSY and HMBC) spectra, as well as low and high-resolution mass spectrometric data. In this paper, we report on the structure elucidation of 1.

A Phenethyl bromo ester from Citharexylum fruticosum

A new compound, (2 S)- p-hydroxyphenethyl 2-bromo-2-methyldodeconate (1) and 7,3′-dimethoxy-5,4′-dihydroxy flavone, together with lupeol and stigmasterol were isolated from the stem bark of Citharexylum fruticosum (Verbenaceae). The structures of the compounds were established on the basis of the interpretation of NMR (1H, 13C, COSY and HMBC) spectra, as well as low and high-resolution mass spectrometric data. In this paper, we report on the structure elucidation of 1.

Cytotoxic benzil and coumestan derivatives from Tephrosia calophylla

A benzil, calophione A, 1-(6'-Hydroxy-1',3'-benzodioxol-5'-yl)-2-(6''-hydroxy-2''-isopropenyl-2'',3''-dihydro-benzofuran-5''-yl)-ethane-1,2-dione and three coumestan derivatives, tephcalostan B, C and D were isolated from the roots of Tephrosia calophylla. Their structures were deduced from spectroscopic data, including 2D NMR (1)H-(1)H COSY and (13)C-(1)H COSY experiments. Compounds were evaluated for cytotoxicity against RAW (mouse macrophage cells) and HT-29 (colon cancer cells) cancer cell lines and antiprotozoal activity against various parasitic protozoa. Calophione A exhibited significant cytotoxicity with IC(50) of 5.00 (RAW) and 2.90microM (HT-29), respectively.