Phytochemical characterization and bioactivity toward breast cancer cells of unhydrolyzed and acid-hydrolyzed extracts of Fagonia indica.

Phytochemicals from the genus, Fagonia, have been attracting increasing attention due to their potential beneficial effects on human health. Fagonia species contain various types of phytochemicals such as flavonoids, alkaloids, saponins, terpenoids, coumarins and tannins. In this study, we investigated the phytochemical composition of unhydrolyzed and acid-hydrolyzed extracts of Fagonia indica and their bioactivity toward breast cancer MCF-7 cells in vitro. The results revealed that F. indica contains phytochemicals consistent with the reported phytochemical composition of this Fagonia species, with greater amounts of aglycones detected in the hydrolyzed extract. The crude extract of F. indica without acid hydrolysis was found to be ineffective in inhibiting the growth of MCF-7 cells at doses below 1000 µg/mL. However, after acid hydrolysis (to mimic gastro-intestinal hydrolysis), the F. indica extract became growth-inhibitory to MCF-7 cells as low as 10 µg/mL and the cytotoxicity increased with increasing dose and time of treatment. The results suggest that F. indica extracts contain phytochemicals in glycosidic forms whose aglycones are active as anti-proliferative agents toward breast cancer cells in vitro.

Integration of mass spectral fingerprinting analysis with precursor ion (MS1) quantification for the characterisation of botanical extracts: application to extracts of Centella asiatica (L.) Urban.

INTRODUCTION: The phytochemical composition of plant material governs the bioactivity and potential health benefits as well as the outcomes and reproducibility of laboratory studies and clinical trials. OBJECTIVE: The objective of this work was to develop an efficient method for the in-depth characterisation of plant extracts and quantification of marker compounds that can be potentially used for subsequent product integrity studies. Centella asiatica (L.) Urb., an Ayurvedic herb with potential applications in enhancing mental health and cognitive function, was used as a case study. METHODS: A quadrupole time-of-flight analyser in conjunction with an optimised high-performance liquid chromatography (HPLC) separation was used for in-depth untargeted fingerprinting and post-acquisition precursor ion quantification to determine levels of distinct phytochemicals in various C. asiatica extracts. RESULTS: We demonstrate the utility of this workflow for the characterisation of extracts of C. asiatica. This integrated workflow allowed the identification or tentative identification of 117 compounds, chemically interconnected based on Tanimoto chemical similarity, and the accurate quantification of 24 phytochemicals commonly found in C. asiatica extracts. CONCLUSION: We report a phytochemical analysis method combining liquid chromatography, high resolution mass spectral data acquisition, and post-acquisition interrogation that allows chemical fingerprints of botanicals to be obtained in conjunction with accurate quantification of distinct phytochemicals. The variability in the composition of specialised metabolites across different C. asiatica accessions was substantial, demonstrating that detailed characterisation of plant extracts is a prerequisite for reproducible use in laboratory studies, clinical trials and safe consumption. The methodological approach is generally applicable to other botanical products.

Vitamin C Activates the Folate-Mediated One-Carbon Cycle in C2C12 Myoblasts.

Vitamin C (L-ascorbic acid, AA) is an essential cellular antioxidant and cofactor for several α-ketoglutarate-dependent dioxygenases. As an antioxidant, AA interacts with vitamin E to control oxidative stress. While several reports suggest an interaction of AA with folate (vitamin B9) in animals and humans, little is known about the nature of the interaction and the underlying molecular mechanisms at the cellular level. We used an untargeted metabolomics approach to study the impact of AA on the metabolome of C2C12 myoblast cells. Compared to untreated cells, treatment of C2C12 cells with AA at 100 µM resulted in enhanced concentrations of folic acid (2.5-fold) and 5-methyl-tetrahydrofolate (5-methyl-THF, 10-fold increase) whereas the relative concentrations of 10-formyl-tetrahydrofolate decreased by >90% upon AA pretreatment, indicative of increased utilization for the biosynthesis of active THF metabolites. The impact of AA on the folate-mediated one-carbon cycle further manifested itself as an increase in the levels of methionine, whose formation from homocysteine is 5-methyl-THF dependent, and an increase in thymidine, whose formation from deoxyuridine monophosphate (dUMP) is dependent on 5,10-methylene-THF. These findings shed new light on the interaction of AA with the folate-mediated one-carbon cycle and partially explain clinical findings that AA supplementation enhances erythrocyte folate status and that it may decrease serum levels of homocysteine, which is considered as a biomarker of cardiovascular disease risk.

Activity of meadowfoam (Limnanthes alba) seed meal glucolimnanthin degradation products against soilborne pathogens.

Meadowfoam (Limnanthes alba L.) is a herbaceous winter-spring annual grown as a commercial oilseed crop. The meal remaining after oil extraction from the seed contains up to 4% of the glucosinolate glucolimnanthin. Degradation of glucolimnanthin yields toxic breakdown products, and therefore the meal may have potential in the management of soilborne pathogens. To maximize the pest-suppressive potential of meadowfoam seed meal, it would be beneficial to know the toxicity of individual glucolimnanthin degradation products against specific soilborne pathogens. Meloidogyne hapla second-stage juveniles (J2) and Pythium irregulare and Verticillium dahliae mycelial cultures were exposed to glucolimnanthin as well as its degradation products. Glucolimnanthin and its degradation product, 2-(3-methoxyphenyl)acetamide, were not toxic to any of the soilborne pathogens at concentrations up to 1.0 mg/mL. Two other degradation products, 2-(3-methoxymethyl)ethanethioamide and 3-methoxyphenylacetonitrile, were toxic to M. hapla and P. irregulare but not V. dahliae. The predominant enzyme degradation product, 3-methoxybenzyl isothiocyanate, was the most toxic compound against all of the soilborne pathogens, with M. hapla being the most sensitive with EC(50) values (0.0025 ± 0.0001 to 0.0027 ± 0.0001 mg/mL) 20-40 times lower than estimated EC(50) mortality values generated for P. irregulare and V. dahliae (0.05 and 0.1 mg/mL, respectively). The potential exists to manipulate meadowfoam seed meal to promote the production of specific degradation products. The conversion of glucolimnanthin into its corresponding isothiocyanate should optimize the biopesticidal properties of meadowfoam seed meal against M. hapla, P. irregulare, and V. dahliae.