Chemical Studies of Phytoestrogens and Related Compounds in Dietary Supplements: Flax and Chaparral

Obermeyer, William R.; Musser, Steven M.; Betz, Joseph M.; Casey, R.; Pohland, Albert E; Page, Samuel W.

doi:10.3181/00379727-208-43824

Cited by 114 publications

(61 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The ER-positive MCF-7 proved to be far more sensitive as compared to MDA-MB-231, which could be ascribed to an estrogen-receptor modulation by justicidin B. Lignans including those abundant in Linum species have been well established as phytoestrogens and estrogen receptor modulators [26][27][28], and most probably the established alternative cellular events at the signal transduction level in MCF-7 vs. MDA-MB-231 could be attributed to the estrogen receptor expression in the former cell lines. These discrepancies between the two cell lines nevertheless need further clarification.…”

Section: Discussionmentioning

confidence: 99%

Effect of justicidin B – a potent cytotoxic and pro-apoptotic arylnaphtalene lignan on human breast cancer-derived cell lines

Momekov¹,

Konstantinov²,

Dineva³

et al. 2011

neo

View full text Add to dashboard Cite

Justicidin B produced by genetically transformed cultures of Linum leonii was tested for cytotoxic activity and induction of apoptosis in MDA-MB-231 and MCF-7 breast cancer derived cell lines. The tested lignan evoked strong, concentration dependent cytotoxicity in both cell lines, whereby MCF-7 proved to be far more sensitive as compared to MDA-MB-231. The 24 h treatment of both cell lines increased the level of apoptotic DNA fragmentation; however the proapoptotic activity is completely inhibited if the cells are co-incubated with the non-selective pan-caspase inhibitor Boc-Asp(OMe)-fluoromethyl ketone (PCI), which implies that justicidin B, activates programmed cell death via caspase -dependent mechanisms. Exposure of MDA-MB-231 cells with justicidin B leads to concentration dependent decrease in the expression of NFkB; whereas the treatment of MCF-7, is consistent with strong increase in the expression of this transcription factor.

show abstract

Section: Discussionmentioning

confidence: 99%

Effect of justicidin B – a potent cytotoxic and pro-apoptotic arylnaphtalene lignan on human breast cancer-derived cell lines

Momekov¹,

Konstantinov²,

Dineva³

et al. 2011

neo

View full text Add to dashboard Cite

show abstract

“…Many laboratories use high -performance liquid chromatography (HPLC ) coupled with UV detection (Franke and Custer, 1994;Obermeyer et al, 1995 ) due to its low cost; however, these methods are lacking in selectivity and sensitivity, and are typically inadequate for measuring baseline levels of some phytoestrogens in individuals consuming a typical Western diet. A novel approach using HPLC with coulometric array detection (Gamache and Acworth, 1998 ) shows promise for increased selectivity and sensitivity, but depends greatly on the redox potential, resulting in reduced selectivity and sensitivity for some analytes in complex matrices such as serum.…”

Section: Introductionmentioning

confidence: 99%

HPLC-MS/MS method for the measurement of seven phytoestrogens in human serum and urine

Valentín-Blasini

Blount

Rogers

et al. 2000

J Expo Sci Environ Epidemiol

View full text Add to dashboard Cite

The elevated exposure of children to hormonally active dietary phytoestrogens has led to the need for rapid, sensitive, and precise assays for phytoestrogen metabolites in physiological matrices. Here we report the development of a high -performance liquid chromatography ( HPLC ) MS / MS method for the quantitative detection of seven phytoestrogens in human serum and urine. The method uses enzymatic deconjugation of the phytoestrogen metabolites followed by solid phase extraction ( SPE ) and reverse -phase HPLC. The phytoestrogens are detected using a Sciex API III heated nebulizer atmospheric pressure chemical ionization ( HN -APCI ) interface coupled with tandem mass spectrometry. This method allows the detection of the primary dietary phytoestrogens ( isoflavones and lignans ) in human serum and urine with limits of detection ( LODs ) in the low parts per billion range. The combination of tandem mass spectrometry and chromatographic separation of the analytes helps ensure the selectivity of the method. Stable isotope -labeled internal standards for all seven analytes improve the precision of the assay, resulting in interday CV values of < 10% for most compounds studied. The accuracy and precision of the method were monitored over time using quality control ( QC ) samples containing known amounts of phytoestrogens. The majority of phytoestrogens in human sera and urine are present as their glucuronide and sulfate conjugates. Therefore, the thoroughness of deconjugation for each sample was monitored by the addition of a conjugated internal standard and subsequent detection of deconjugated compound. This method proves to be efficacious for measuring baseline urinary phytoestrogen levels in the American population and should prove useful for assessing the modulatory effects of dietary phytoestrogens on endocrine disrupter action in children.

show abstract

“…The enzyme-assisted release of low molecular phenolic compounds from the extracts of flaxseed hulls was investigated by several authors [Obermeyer et al, 1995 Renouard et al, 2010]. They used different solvent systems for extraction and different enzymes (β-glucuronidase, sulfatase, cellulase) for hydrolysis.…”

Section: Results and Dicussionmentioning

confidence: 99%

SE-HPLC-DAD Analysis of Flaxseed Lignan Macromolecule and its Hydrolysates

Kosińska¹,

Urbalewicz²,

Penkacik³

et al. 2011

Pol. J. Food Nutr. Sci.

View full text Add to dashboard Cite

liquid chromatography with a diode array detection (SE-HPLC-DAD) in analysis of lignan macromolecule (LM) and phenolic compounds liberated from LM after chemical and enzymatic hydrolysis. MATERIAL AND METHODS MaterialGround, partially defatted flaxseeds were purchased from the "Ekoprodukt" company (Częstochowa, Poland). Preparation of crude extractThe material was defatted with hexane and then phenolic compounds were extracted using a dioxane:ethanol (1:1; v:v) mixture [Johnsson et al., 2000]. The extraction was carried out for 16 h, at 60°C with continuous shaking in a water bath. Then, solvent was evaporated using Büchi Rotavapor R-200 at 40°C. Amberlite column chromatographyThe flaxseed phenolic compounds extract was purified using column chromatography on Amberlite XAD-16 (34 mm i.d.; 170 mm length) [Srivastava et al., 2010]. A 5-g portion of the extract was suspended in 5 mL of distilled water and loaded on the column. Firstly, water soluble compounds, mainly sugars, were eluted using distilled water and discarded, then solvent was changed over to methanol which eluted phenolic compounds. The solvent was removed using Büchi Rotavapor R-200. Base hydrolysisThe purified extract was subjected to base hydrolysis. Briefly, the purified extract was suspended in 0.3 mol/L NaOH, SE-HPLC-DAD Analysis of Flaxseed Lignan Macromolecule and its HydrolysatesAgnieszka Kosińska, Anna Urbalewicz, Kamila Penkacik, Magdalena Karamać, Ryszard Amarowicz* Sciences, Olsztyn, ul. Tuwima 10, Poland Key words: flaxseed, phenolics, lignans, SE-HPLC-DAD, hydrolysis A lignan macromolecule (LM) was extracted from defatted flaxseeds using an ethanol-dioxan system (1:1, v/v) and purified using Amberlite column chromatography with water and methanol as mobile phases. The LM was subjected to chemical hydrolysis (base, acid, base & acid), as well as to enzymatic processing using pepsin, pancreatin, cellulase, and β-glucuronidase. Division of Food Sciences, Institute of Animal Reproduction and Food Research of the Polish Academy ofThe study revealed that lignan macromolecule in flaxseed was not homogenous. The chemical hydrolysis as well as enzymatic treatment using β-glucuronidase and cellulase released low molecular phenolic compounds from the lignan macromolecule. The liberation of secoisolariciresinol (SECO) and free phenolic acids (p-coumaric and ferulic acids) from flaxseed lignan macromolecule as a result of the base and acid hydrolyses was noted. The application of pepsin and pancreatin did not change the composition of the lignan macromolecule.

show abstract

Chemical Studies of Phytoestrogens and Related Compounds in Dietary Supplements: Flax and Chaparral

Cited by 114 publications

References 0 publications

Effect of justicidin B – a potent cytotoxic and pro-apoptotic arylnaphtalene lignan on human breast cancer-derived cell lines

Effect of justicidin B – a potent cytotoxic and pro-apoptotic arylnaphtalene lignan on human breast cancer-derived cell lines

HPLC-MS/MS method for the measurement of seven phytoestrogens in human serum and urine

SE-HPLC-DAD Analysis of Flaxseed Lignan Macromolecule and its Hydrolysates

Contact Info

Product

Resources

About