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Dresler S, Strzemski M, Baczewska I, Koselski M, Hassanpouraghdam MB, Szczepanek D, Sowa I, Wójciak M, Hanaka A. Extraction of Isoflavones, Alpha-Hydroxy Acids, and Allantoin from Soybean Leaves-Optimization by a Mixture Design of the Experimental Method. Molecules 2023; 28:molecules28093963. [PMID: 37175385 PMCID: PMC10179801 DOI: 10.3390/molecules28093963] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Revised: 04/27/2023] [Accepted: 05/04/2023] [Indexed: 05/15/2023] Open
Abstract
Soybeans are commonly known as a valuable source of biologically active compounds including isoflavones as well as allantoin and alpha-hydroxy acids. Since these compounds exhibit skin therapeutic effects, they are widely used in the cosmetic and pharmaceutical industries. The presented paper shows the optimization of three solvent systems (ethanol, water, and 1,3-propanediol) to increase the extraction efficiency of isoflavones (daidzin, genistin, 6″-O-malonyldaidzin, 6″-O-malonylglycitin, 6″-O-malonylgenistin), allantoin, and alpha-hydroxy acids (citric acid, malic acid) from soybean leaves. A simplex centroid mixture design for three solvents with interior points was applied for the experimental plan creation. Based on the obtained results of metabolite extraction yield in relation to solvent composition, polynomial regression models were developed. All models were significant, with predicted R-squared values between 0.77 and 0.99, while in all cases the model's lack of fit was not significant. The optimal mixture composition enabling the maximization of extraction efficiency was as follows: 32.9% ethanol, 53.9% water, and 13.3% propanediol (v/v/v). Such a mixture composition provided the extraction of 99%, 91%, 100%, 92%, 99%, 70%, 92%, and 69% of daidzin, genistin, 6″-O-malonyldaidzin, 6″-O-malonylglycitin, 6″-O-malonylgenistin, allantoin, citric acid, and malic acid, respectively. The solvent mixture composition developed provides a good extraction efficiency of the metabolites from soybean leaves and high antioxidant properties.
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Affiliation(s)
- Sławomir Dresler
- Department of Analytical Chemistry, Medical University of Lublin, Chodźki 4a, 20-093 Lublin, Poland
- Department of Plant Physiology and Biophysics, Institute of Biological Sciences, Maria Curie-Skłodowska University, Akademicka 19, 20-033 Lublin, Poland
| | - Maciej Strzemski
- Department of Analytical Chemistry, Medical University of Lublin, Chodźki 4a, 20-093 Lublin, Poland
| | - Izabela Baczewska
- Department of Analytical Chemistry, Medical University of Lublin, Chodźki 4a, 20-093 Lublin, Poland
| | - Mateusz Koselski
- Department of Plant Physiology and Biophysics, Institute of Biological Sciences, Maria Curie-Skłodowska University, Akademicka 19, 20-033 Lublin, Poland
| | | | - Dariusz Szczepanek
- Chair and Department of Neurosurgery and Paediatric Neurosurgery, Medical University of Lublin, 20-090 Lublin, Poland
| | - Ireneusz Sowa
- Department of Analytical Chemistry, Medical University of Lublin, Chodźki 4a, 20-093 Lublin, Poland
| | - Magdalena Wójciak
- Department of Analytical Chemistry, Medical University of Lublin, Chodźki 4a, 20-093 Lublin, Poland
| | - Agnieszka Hanaka
- Department of Plant Physiology and Biophysics, Institute of Biological Sciences, Maria Curie-Skłodowska University, Akademicka 19, 20-033 Lublin, Poland
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Yang H, Li T, Cao W. Optimizing pre-treatment of alkaline hydrolysis RP-HPLC for enhancing accuracy of soy isoflavone determination. J Chromatogr B Analyt Technol Biomed Life Sci 2022; 1207:123382. [PMID: 35878432 DOI: 10.1016/j.jchromb.2022.123382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2022] [Revised: 06/11/2022] [Accepted: 07/18/2022] [Indexed: 11/18/2022]
Abstract
Isoflavones (IFs) are important bioactive compounds which offers several benefits to human health. Despite the importance of IFs content, there are still some deficiencies in the existing methods. The objective of this study is to optimize key parameters of alkaline hydrolysis method for enhancing both reliability and accuracy of quantitative analysis of IFs contents in soybeans and soy protein products. Solvent type, extraction temperature, heating mode, alkaline concentration, hydrolysis temperature, hydrolysis time and some details are key points to target analytes which yield determining parameters. The biggest IFs content was obtained by extraction using methanol (MeOH)/water (80:20, v/v) in a 75 ℃ oven for 2 h, and hydrolyzation with 3 M NaOH solution at a room temperature for 10 mins. The total IFs content obtained by the improved method has increased by 16.4% compared with AOAC Official Method 2001.10. The accuracy of the method was evaluated using the relative standard deviation (RSD). Intraday accuracies in the total amount of isoflavones of four samples were 0.03%-0.63% (n = 3). Interday accuracy in the total amount of isoflavones was 2.71% (n = 6). LOD of IFs ranged from 0.1μg/mL for aglycones to 0.2μg/mL for glucosides. LOQ of IFs ranged from 0.3μg/mL for aglycones to 0.5μg/mL for glucosides. The improved method was proven to be a more accurate way to determine IFs contents in soybeans and soy protein products and thus making it useful for quality control and systematic in-depth study of soybeans and soy products; even to further assess the dietary soy exposure and the soy-health association.
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Affiliation(s)
- Hong Yang
- Wilmar (Shanghai) Biotechnology Research & Development Center Co., Ltd. Shanghai 200137, China
| | - Tong Li
- Wilmar (Shanghai) Biotechnology Research & Development Center Co., Ltd. Shanghai 200137, China
| | - Wenming Cao
- Wilmar (Shanghai) Biotechnology Research & Development Center Co., Ltd. Shanghai 200137, China.
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Effect of Tempeh on Gut Microbiota and Anti-Stress Activity in Zebrafish. Int J Mol Sci 2021; 22:ijms222312660. [PMID: 34884465 PMCID: PMC8658004 DOI: 10.3390/ijms222312660] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 11/15/2021] [Accepted: 11/16/2021] [Indexed: 12/02/2022] Open
Abstract
Rhizopus oryzae is a fungus used to ferment tempeh in Indonesia and is generally recognized as safe (GRAS) for human consumption by the USA FDA. We previously assessed the effect of a tempeh extract on cortisol levels in zebrafish but did not include behavioral studies. Here, we measured the GABA content in three strains of Rhizopus oryzae, two isolated by us (MHU 001 and MHU 002) and one purchased. We then investigated the effect of tempeh on cortisol and the gut microbiota in a zebrafish experimental model. GABA concentration was the highest in MHU 002 (9.712 ± 0.404 g kg−1) followed by our MHU 001 strain and the purchased one. The fish were divided into one control group fed a normal diet and three experimental groups fed soybean tempeh fermented with one of the three strains of Rhizopus oryzae. After two weeks, individual fish were subjected to unpredicted chronic stress using the novel tank diving test and the tank light–dark test. Next-generation sequencing was used to analyze gut microbial communities and RT-PCR to analyze the expression of BDNF (brain-derived neurotrophic factor) gene and of other genes involved in serotonin signaling/metabolism in gut and brain. Tempeh-fed zebrafish exhibited increased exploratory behavior (less stress) in both tank tests. They also had significantly reduced gut Proteobacteria (include E. coli) (51.90% vs. 84.97%) and significantly increased gut Actinobacteria (include Bifidobacterium spp.) (1.80% vs. 0.79%). The content of Bifidobacteriumadolescentis, a “psychobiotic”, increased ten-fold from 0.04% to 0.45%. Tempeh also increases BDNF levels in zebrafish brain. Rhizopus oryzae MHU 001 greatly improved the anti-stress effect of tempeh and microbiota composition in zebrafish gut.
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Yu L, Rios E, Castro L, Liu J, Yan Y, Dixon D. Genistein: Dual Role in Women's Health. Nutrients 2021; 13:3048. [PMID: 34578926 PMCID: PMC8472782 DOI: 10.3390/nu13093048] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2021] [Revised: 08/25/2021] [Accepted: 08/25/2021] [Indexed: 12/22/2022] Open
Abstract
Advanced research in recent years has revealed the important role of nutrients in the protection of women's health and in the prevention of women's diseases. Genistein is a phytoestrogen that belongs to a class of compounds known as isoflavones, which structurally resemble endogenous estrogen. Genistein is most often consumed by humans via soybeans or soya products and is, as an auxiliary medicinal, used to treat women's diseases. In this review, we focused on analyzing the geographic distribution of soybean and soya product consumption, global serum concentrations of genistein, and its metabolism and bioactivity. We also explored genistein's dual effects in women's health through gathering, evaluating, and summarizing evidence from current in vivo and in vitro studies, clinical observations, and epidemiological surveys. The dose-dependent effects of genistein, especially when considering its metabolites and factors that vary by individuals, indicate that consumption of genistein may contribute to beneficial effects in women's health and disease prevention and treatment. However, consumption and exposure levels are nuanced because adverse effects have been observed at lower concentrations in in vitro models. Therefore, this points to the duplicity of genistein as a possible therapeutic agent in some instances and as an endocrine disruptor in others.
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Affiliation(s)
| | | | | | | | | | - Darlene Dixon
- Molecular Pathogenesis Group, Mechanistic Toxicology Branch (MTB), Division of the National Toxicology Program (DNTP), National Institute of Environmental Health Sciences (NIEHS), National Institutes of Health (NIH), Research Triangle Park, Durham, NC 27709, USA; (L.Y.); (E.R.); (L.C.); (J.L.); (Y.Y.)
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Chen YC, Hsieh SL, Hu CY. Effects of Red-Bean Tempeh with Various Strains of Rhizopus on GABA Content and Cortisol Level in Zebrafish. Microorganisms 2020; 8:E1330. [PMID: 32878315 PMCID: PMC7565155 DOI: 10.3390/microorganisms8091330] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2020] [Revised: 08/24/2020] [Accepted: 08/25/2020] [Indexed: 12/03/2022] Open
Abstract
Tempeh is traditionally produced by fermenting soybean with the fungus Rhizopus oligosporus found in banana leafs. We wanted to investigate if Taiwan's flavorful red bean could be used as a healthy substitute for soybeans in tempeh. One bioactive component of tempeh is γ-Aminobutyric acid (GABA). We measured GABA content and shelf-life-related antimicrobial activity in red-bean tempeh made with four strains of Rhizopus, one purchased strain of Rhizopus, and an experimental co-cultured group (Rhizopus and Lactobacillus rhamnosus BCRC16000) as well as cortisol in red-bean-tempeh-treated zebrafish. GABA was highest in the co-culture group (19.028 ± 1.831 g kg-1), followed by screened Strain 1, the purchased strain, and screened Strain 4. All strains had antibacterial activity on S. aureus and B. cereus. The extract significantly reduced cortisol in zebrafish. However, Strain 1, with less GABA than some of the other strains, had the best effect on cortisol level, suggesting that other components in red-bean tempeh may also affect stress-related cortisol. We found the benefits of red-bean tempeh to be similar to those reported for soybean-produced tempeh, suggesting that it could be produced as an alternative product. Considering the Taiwanese appreciation of the red-bean flavor, it might find a welcoming market.
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Affiliation(s)
- Yo-Chia Chen
- Department of Biological Science and Technology, National Pingtung University of Science and Technology, Pingtung 912301, Taiwan;
| | - Shu-Ling Hsieh
- Department of Seafood Science, National Kaohsiung University of Science and Technology, Kaohsiung 81157, Taiwan;
| | - Chun-Yi Hu
- Department of Food Science and Nutrition, Meiho University, Pingtung 912009, Taiwan
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Montero G, Arriagada F, Günther G, Bollo S, Mura F, Berríos E, Morales J. Phytoestrogen coumestrol: Antioxidant capacity and its loading in albumin nanoparticles. Int J Pharm 2019; 562:86-95. [PMID: 30885651 DOI: 10.1016/j.ijpharm.2019.03.029] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2018] [Revised: 03/11/2019] [Accepted: 03/15/2019] [Indexed: 01/21/2023]
Abstract
Coumestrol is a polyphenol with promising therapeutic applications as phytoestrogen, antioxidant and potential cancer chemoprevention agent. The presence of two hydroxyl groups on its chemical structure, with orientation analogous to estradiol, is responsible of both, its antioxidant capacity and its estrogenic activity. However, several studies show that the interaction of polyphenols with food and plasma proteins reduces their antioxidant efficacy. We studied the interaction of coumestrol with bovine serum albumin protein (BSA) by fluorescence spectroscopy and circular dichroism techniques, and the effect of this interaction on its antioxidant activity as a hydroxyl radical scavenger. In addition, coumestrol antioxidant capacity profile using different assays (DPPH, ORAC-FL and ORAC-EPR) was studied. To explain its reactivity we used several methodologies, including DFT calculations, to define its antioxidant mechanism. Coumestrol antioxidant activity unveiled interesting antioxidant properties. BSA interaction with coumestrol reduces significantly photolytic degradation in several media thus preserving its antioxidant properties. Results suggest no significant changes in BSA structure and activity when interacting with coumestrol. Furthermore, this interaction is stronger than for other phytoestrogens such as daidzein and genistein. Considering our promising results, we reported for the first time the fabrication and characterization of coumestrol-loaded albumin nanoparticles. The resulting spherical and homogeneous nanoparticles showed a diameter close to 96 nm. The coumestrol incorporation efficiency in BSA NPs was 22.4%, which is equivalent to 3 molecules of coumestrol for every 10 molecules of BSA.
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Affiliation(s)
- Guillermo Montero
- Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Chile
| | | | - Germán Günther
- Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Chile
| | - Soledad Bollo
- Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Chile
| | - Francisco Mura
- Facultad de Química y Biología, Universidad de Santiago de Chile, Chile
| | - Eduardo Berríos
- Instituto de Química y Bioquímica, Facultad de Ciencias, Universidad de Valparaíso, Chile
| | - Javier Morales
- Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Chile.
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Zhao H, Song X, Zhang Y, Sheng X. Molecular interaction between MeOH and genistein during soy extraction. RSC Adv 2019; 9:39170-39179. [PMID: 35540639 PMCID: PMC9076023 DOI: 10.1039/c9ra05976h] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Accepted: 11/22/2019] [Indexed: 11/23/2022] Open
Abstract
Genistein has received great attention due to its possible anti-oxidant properties. The interaction between genistein and the extraction solvent helps in understanding the extraction efficiency. Hydrogen bonding plays a crucial role in liquid systems. Density functional theory quantum chemical computations in both gas phase and solution were performed to investigate the molecular interaction between genistein and methanol. All the resulting complexes (MeOH : genistein = 1 : 1, 2 : 1, 3 : 1, 6 : 1) were studied using the B3LYP-D3 computational level and the cc-pVTZ basis set. Binding energies demonstrate that more MeOH molecules surrounding genistein could stabilize the system more. Geometry optimizations show that there are strong O–H⋯O interactions between MeOH and genistein. The electron density and the corresponding Laplacian of charge density at bond critical points were also calculated using AIM theory, and the results are in line with the structural and energetic analysis of the studied system. Moreover, energy decomposition analysis shows that the exchange energy term has the largest contribution to the attraction interaction energy as compared with other energy terms. Meanwhile, this study shows that the MeOH–genistein system is more stable under basic conditions. This study could help increase the efficiency of extraction. The interaction between genistein and extraction solvent helps in understanding the extraction efficiency.![]()
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Affiliation(s)
- Hailiang Zhao
- Province Key Laboratory of Cereal Resource Transformation and Utilization
- Henan University of Technology
- 450001 Zhengzhou
- China
- College of Chemistry, Chemical and Environmental Engineering
| | - Xue Song
- College of Chemistry, Chemical and Environmental Engineering
- Henan University of Technology
- 450001 Zhengzhou
- China
| | - Yingming Zhang
- College of Chemistry, Chemical and Environmental Engineering
- Henan University of Technology
- 450001 Zhengzhou
- China
| | - Xia Sheng
- College of Chemistry, Chemical and Environmental Engineering
- Henan University of Technology
- 450001 Zhengzhou
- China
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8
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Coumestrol inhibits autoantibody production through modulating Th1 response in experimental autoimmune thyroiditis. Oncotarget 2018; 7:52797-52809. [PMID: 27384679 PMCID: PMC5288149 DOI: 10.18632/oncotarget.10353] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Accepted: 06/15/2016] [Indexed: 11/25/2022] Open
Abstract
Coumestrol is a common phytoestrogen found in plants and Chinese medicinal herbs. Its influences on experimental autoimmune thyroiditis (EAT) were investigated in this study. Female adult CBA/J mice were fed with drinking water containing 1% Tween80 only (Control group), 0.8 mg/l (L group) and 8 mg/l coumestrol (H group) from 6 to 15 weeks of age, respectively. Their serum coumestrol concentrations were determined by high performance liquid chromatography, which were undetectable, 43.70 ± 21.74 ng/ml and 135.07 ± 70.40 ng/ml, respectively. In addition, the mice (n = 14–16/group) were immunized twice with thyroglobulin (Tg) and Freund's adjuvant to induce EAT during the meantime. Although no overt changes in the extent of intrathyroidal mononuclear cell infiltration were shown in the two coumestrol-treated groups as compared with the controls, serum anti-Tg IgG2a, IgG3 and IgG1 titers, ratio of IgG2a to IgG1 and the percentage of T helper (Th)1 cells in the splenocytes were significantly reduced in the L group. Another consistent change was the significantly decreased expression of splenic IFN-γ mRNA after low dose of coumestrol exposure. Uterine weight was also markedly reduced in the mice of L group. These findings suggest that coumestrol treatment may have some beneficial actions against thyroid-specific autoantibody production in the development of autoimmune thyroiditis through suppression of Th1 response due to its anti-estrogenic activity.
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Rizzo G, Baroni L. Soy, Soy Foods and Their Role in Vegetarian Diets. Nutrients 2018; 10:E43. [PMID: 29304010 PMCID: PMC5793271 DOI: 10.3390/nu10010043] [Citation(s) in RCA: 175] [Impact Index Per Article: 29.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Revised: 11/30/2017] [Accepted: 01/03/2018] [Indexed: 02/07/2023] Open
Abstract
Soy is a basic food ingredient of traditional Asian cuisine used for thousands of years. In Western countries, soybeans have been introduced about a hundred years ago and recently they are mainly used for surrogate foods production. Soy and soy foods are common nutritional solutions for vegetarians, due to their high protein content and versatility in the production of meat analogues and milk substitutes. However, there are some doubts about the potential effects on health, such as the effectiveness on cardiovascular risk reduction or, conversely, on the possible disruption of thyroid function and sexual hormones. The soy components that have stimulated the most research interest are isoflavones, which are polyphenols with estrogenic properties highly contained in soybeans. In this review, we discuss the characteristics of soy and soy foods, focusing on their nutrient content, including phytoestrogens and other bioactive substances that are noteworthy for vegetarians, the largest soy consumers in the Western countries. The safety of use will also be discussed, given the growing trend in adoption of vegetarian styles and the new soy-based foods availability.
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Affiliation(s)
| | - Luciana Baroni
- Primary Care Unit, Northern District, Local Health Unit 2, 31100 Treviso, Italy.
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Park HJ, Jung MY. One step salting-out assisted liquid-liquid extraction followed by UHPLC-ESI-MS/MS for the analysis of isoflavones in soy milk. Food Chem 2017; 229:797-804. [DOI: 10.1016/j.foodchem.2017.02.145] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Revised: 01/30/2017] [Accepted: 02/28/2017] [Indexed: 10/20/2022]
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Kuligowski M, Pawłowska K, Jasińska-Kuligowska I, Nowak J. Isoflavone composition, polyphenols content and antioxidative activity of soybean seeds during tempeh fermentation. CYTA - JOURNAL OF FOOD 2016. [DOI: 10.1080/19476337.2016.1197316] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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12
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López-Gutiérrez N, Romero-González R, Garrido Frenich A, Martínez Vidal JL. Identification and quantification of the main isoflavones and other phytochemicals in soy based nutraceutical products by liquid chromatography-orbitrap high resolution mass spectrometry. J Chromatogr A 2014; 1348:125-36. [PMID: 24835762 DOI: 10.1016/j.chroma.2014.04.090] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2014] [Revised: 04/11/2014] [Accepted: 04/28/2014] [Indexed: 11/24/2022]
Abstract
The specific phytochemicals composition of soy nutritional supplements is usually not labelled. Hence, 12 dietary supplements were analyzed in order to detect and identify the main phytochemicals present in these samples, using a database containing 60 compounds. Ultra-high performance liquid chromatography coupled to single-stage Orbitrap high resolution mass spectrometry (UHPLC-Orbitrap-MS) has been used. Two consecutive extractions, using as extraction solvent a mixture of methanol:water (80:20, v/v), were employed, followed by two dilutions (10 or 100 times depending on the concentration of the components in the sample) with a mixture of an aqueous solution of ammonium acetate 30mM:methanol (50:50, v/v). The method was validated, obtaining adequate recovery and precision values. Limits of detection (LODs) and quantification (LOQs) were calculated, ranging from 2 to 150μgL(-1). Isoflavones were the predominant components present in the analyzed supplements with values higher than 93% of the total amount of phytochemicals in all cases. The aglycones (genistein, daidzein, glycitein and biochanin A) as well as their three conjugated forms, β-glucosides (genistin, daizin and glycitin) were detected and quantified, being daidzein the isoflavone detected at higher concentration in 8 out of 12 samples reported, with values ranging from 684 to 35,970mgkg(-1), whereas biochanin A was detected at very low concentrations, ranging from 18 to 50mgkg(-1). Moreover, other phytochemicals as flavones, flavonols, flavanones and phenolic acids were also detected and quantified.
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Affiliation(s)
- Noelia López-Gutiérrez
- Department of Chemistry and Physics (Analytical Chemistry Area), Research Centre for Agricultural and Food Biotechnology (BITAL), University of Almería, Agrifood Campus of International Excellence, ceiA3, Carretera de Sacramento s/n, E-04120 Almería, Spain
| | - Roberto Romero-González
- Department of Chemistry and Physics (Analytical Chemistry Area), Research Centre for Agricultural and Food Biotechnology (BITAL), University of Almería, Agrifood Campus of International Excellence, ceiA3, Carretera de Sacramento s/n, E-04120 Almería, Spain
| | - Antonia Garrido Frenich
- Department of Chemistry and Physics (Analytical Chemistry Area), Research Centre for Agricultural and Food Biotechnology (BITAL), University of Almería, Agrifood Campus of International Excellence, ceiA3, Carretera de Sacramento s/n, E-04120 Almería, Spain.
| | - José Luis Martínez Vidal
- Department of Chemistry and Physics (Analytical Chemistry Area), Research Centre for Agricultural and Food Biotechnology (BITAL), University of Almería, Agrifood Campus of International Excellence, ceiA3, Carretera de Sacramento s/n, E-04120 Almería, Spain
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Yoshiara LY, Madeira TB, Delaroza F, da Silva JB, Ida EI. Optimization of soy isoflavone extraction with different solvents using the simplex-centroid mixture design. Int J Food Sci Nutr 2012; 63:978-86. [PMID: 22621769 DOI: 10.3109/09637486.2012.690026] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The objective of this study was to optimize the extraction of different isoflavone forms (glycosidic, malonyl-glycosidic, aglycone and total) from defatted cotyledon soy flour using the simplex-centroid experimental design with four solvents of varying polarity (water, acetone, ethanol and acetonitrile). The obtained extracts were then analysed by high-performance liquid chromatography. The profile of the different soy isoflavones forms varied with different extractions solvents. Varying the solvent or mixture used, the extraction of different isoflavones was optimized using the centroid-simplex mixture design. The special cubic model best fitted to the four solvents and its combination for soy isoflavones extraction. For glycosidic isoflavones extraction, the polar ternary mixture (water, acetone and acetonitrile) achieved the best extraction; malonyl-glycosidic forms were better extracted with mixtures of water, acetone and ethanol. Aglycone isoflavones, water and acetone mixture were best extracted and total isoflavones, the best solvents were ternary mixture of water, acetone and ethanol.
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Affiliation(s)
- Luciane Yuri Yoshiara
- Department of Food Science and Technology, Universidade Estadual de Londrina, Londrina, Paraná, Brazil
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Xiao CW, Wood CM, Robertson P, Gilani GS. Protease inhibitor activities and isoflavone content in commercial soymilks and soy-based infant formulas sold in Ottawa, Canada. J Food Compost Anal 2012. [DOI: 10.1016/j.jfca.2011.10.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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15
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da Silva JG, e Silva MRL, de Oliveira AC, SouzaDe JR, Vaz CMP, de Castro CSP. Cathodic adsorptive stripping voltammetric determination of rutin in soybean cultivars. J Food Compost Anal 2012. [DOI: 10.1016/j.jfca.2011.04.013] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Alezandro MR, Granato D, Lajolo FM, Genovese MI. Nutritional aspects of second generation soy foods. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2011; 59:5490-5497. [PMID: 21480674 DOI: 10.1021/jf200061c] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Samples of 15 second generation soy-based products (n = 3), commercially available, were analyzed for their protein and isoflavone contents and in vitro antioxidant activity, by means of the Folin-Ciocalteu reducing ability, DPPH radical scavenging capacity, and oxygen radical absorbance capacity. Isoflavone identification and quantification were performed by high-performance liquid chromatography. Products containing soy and/or soy-based ingredients represent important sources of protein in addition to the low fat amounts. However, a large variation in isoflavone content and in vitro antioxidant capacity was observed. The isoflavone content varied from 2.4 to 18.1 mg/100 g (FW), and soy kibe and soy sausage presented the highest amounts. Chocolate had the highest antioxidant capacity, but this fact was probably associated with the addition of cocoa liquor, a well-known source of polyphenolics. This study showed that the soy-based foods do not present a significant content of isoflavones when compared with the grain, and their in vitro antioxidant capacity is not related with these compounds but rather to the presence of other phenolics and synthetic antioxidants, such as sodium erythorbate. However, they may represent alternative sources and provide soy protein, isoflavones, and vegetable fat for those who are not ready to eat traditional soy foods.
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Affiliation(s)
- Marcela Roquim Alezandro
- Departamento de Alimentos e Nutrição Experimental, FCF, Universidade de São Paulo, São Paulo, SP, Brazil
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Tyug TS, Prasad KN, Ismail A. Antioxidant capacity, phenolics and isoflavones in soybean by-products. Food Chem 2010. [DOI: 10.1016/j.foodchem.2010.04.074] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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18
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Haron H, Shahar S, O'Brien KO, Ismail A, Kamaruddin N, Rahman SA. Absorption of calcium from milk and tempeh consumed by postmenopausal Malay women using the dual stable isotope technique. Int J Food Sci Nutr 2010; 61:125-37. [PMID: 19995131 DOI: 10.3109/09637480903348080] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Assessment of calcium bioavailability from non-dairy foods containing moderate amounts of calcium is especially important in populations that have habitually low dairy consumption. Absorption of calcium from milk and tempeh (a traditional fermented soy product) was compared in a sample of Malay subjects. A randomized, crossover design was utilized to assess calcium absorption in 20 postmenopausal women from either a glass of milk (114 g) or from a meal of tempeh (206 g); each containing 130 mg calcium. At each study of Phase 1 (mid-July) and Phase 2 (mid-August), intravenous (42)Ca and oral (44)Ca were administered and calcium absorption was measured in 24-h urine collections post-dosing; with a 1-month washout period between phases. Absorption of calcium from tempeh did not differ significantly from milk (36.9 +/- 10.6% vs. 34.3 +/- 8.6%, respectively). Due to differences in the calcium content of tempeh, four servings of this product would be needed to get the same amount of absorbed calcium as that obtained from a 4-ounce glass of milk. Tempeh may provide readily available calcium for this population of women at risk for low bone mass.
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Affiliation(s)
- Hasnah Haron
- Department of Nutrition & Dietetics, Faculty of Allied Health Sciences, Universiti Kebangsaan Malaysia, 50300 Kuala Lumpur, Malaysia
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Content and Profile of Isoflavones in Soy-Based Foods as a Function of the Production Process. FOOD BIOPROCESS TECH 2010. [DOI: 10.1007/s11947-009-0311-y] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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20
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Mortensen A, Kulling SE, Schwartz H, Rowland I, Ruefer CE, Rimbach G, Cassidy A, Magee P, Millar J, Hall WL, Kramer Birkved F, Sorensen IK, Sontag G. Analytical and compositional aspects of isoflavones in food and their biological effects. Mol Nutr Food Res 2009; 53 Suppl 2:S266-309. [PMID: 19774555 DOI: 10.1002/mnfr.200800478] [Citation(s) in RCA: 107] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
This paper provides an overview of analytical techniques used to determine isoflavones (IFs) in foods and biological fluids with main emphasis on sample preparation methods. Factors influencing the content of IFs in food including processing and natural variability are summarized and an insight into IF databases is given. Comparisons of dietary intake of IFs in Asian and Western populations, in special subgroups like vegetarians, vegans, and infants are made and our knowledge on their absorption, distribution, metabolism, and excretion by the human body is presented. The influences of the gut microflora, age, gender, background diet, food matrix, and the chemical nature of the IFs on the metabolism of IFs are described. Potential mechanisms by which IFs may exert their actions are reviewed, and genetic polymorphism as determinants of biological response to soy IFs is discussed. The effects of IFs on a range of health outcomes including atherosclerosis, breast, intestinal, and prostate cancers, menopausal symptoms, bone health, and cognition are reviewed on the basis of the available in vitro, in vivo animal and human data.
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Affiliation(s)
- Alicja Mortensen
- The National Food Institute, Technical University of Denmark, Søborg, Denmark
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Haron H, Ismail A, Azlan A, Shahar S, Peng LS. Daidzein and genestein contents in tempeh and selected soy products. Food Chem 2009. [DOI: 10.1016/j.foodchem.2009.01.053] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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22
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Erratum: Analytical and compositional aspects of isoflavones in food and their biological effects. Mol Nutr Food Res 2009. [DOI: 10.1002/mnfr.200700478] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Rostagno MA, Villares A, Guillamón E, García-Lafuente A, Martínez JA. Sample preparation for the analysis of isoflavones from soybeans and soy foods. J Chromatogr A 2009; 1216:2-29. [PMID: 19041977 DOI: 10.1016/j.chroma.2008.11.035] [Citation(s) in RCA: 120] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2008] [Revised: 11/03/2008] [Accepted: 11/13/2008] [Indexed: 12/31/2022]
Abstract
This manuscript provides a review of the actual state and the most recent advances as well as current trends and future prospects in sample preparation and analysis for the quantification of isoflavones from soybeans and soy foods. Individual steps of the procedures used in sample preparation, including sample conservation, extraction techniques and methods, and post-extraction treatment procedures are discussed. The most commonly used methods for extraction of isoflavones with both conventional and "modern" techniques are examined in detail. These modern techniques include ultrasound-assisted extraction, pressurized liquid extraction, supercritical fluid extraction and microwave-assisted extraction. Other aspects such as stability during extraction and analysis by high performance liquid chromatography are also covered.
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Affiliation(s)
- M A Rostagno
- Centro para la Calidad de los Alimentos, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Campus Universitario "Duques de Soria", 42004 Soria, Spain.
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Schwartz H, Sontag G. Comparison of sample preparation methods for analysis of isoflavones in foodstuffs. Anal Chim Acta 2008; 633:204-15. [PMID: 19166724 DOI: 10.1016/j.aca.2008.11.054] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2008] [Revised: 11/22/2008] [Accepted: 11/25/2008] [Indexed: 11/29/2022]
Abstract
Due to the lack of one universally applicable and commonly used reference method, sample preparation in isoflavone (IF) analysis has been performed by many different methods which renders comparison and quality assessment of published IF contents in foodstuffs difficult. In the present work, the impact of different experimental parameters on the IF concentrations determined in soybeans, tofu, soy drink and textured vegetable protein by different extraction and hydrolysis methods was assessed and IF contents obtained by optimized orthogonal methods were compared. Chromatographic analysis was performed by HPLC-UV-ESI-MS. If possible sources of error - which are also pointed out in this work - are avoided, IF contents obtained by extraction, acid-, base- and enzymatic hydrolysis are similar. However, these sample preparation methods differ in the amount of time, standard compounds and instruments required, ruggedness, and in their applicability to analysis of complex composite samples containing soy as minor ingredient. Enzymatic hydrolysis with Helix pomatia juice after extraction by sonication with first 50, then 80% aqueous acetonitrile in the presence of zinc sulfate heptahydrate and after adjustment to </=10% organic solvent turned out to be the method of choice if only aglucone equivalent contents are required. The advantages of this method are short chromatographic run times, smallest danger of coelution, lowest achievable limits of quantitation and therefore best suitability for work-up of complex composite samples and that only aglucone standards are needed for quantitation.
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Affiliation(s)
- Heidi Schwartz
- Department of Analytical and Food Chemistry, Faculty of Chemistry, University of Vienna, Waehringer Strasse 38, A-1090 Vienna, Austria
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Rostagno MA, Palma M, Barroso CG. Ultrasound-assisted extraction of isoflavones from soy beverages blended with fruit juices. Anal Chim Acta 2007; 597:265-72. [PMID: 17683738 DOI: 10.1016/j.aca.2007.07.006] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2007] [Revised: 07/03/2007] [Accepted: 07/03/2007] [Indexed: 11/20/2022]
Abstract
A new method for the fast determination of isoflavones from soy beverages blended with fruit juices without the need of freeze-drying the sample was developed. During the method development, several parameters were studied: solvent (methanol and ethanol), sample:solvent ratio (5:1 to 0.2:1), temperature (10-60 degrees C) and extraction time (5-30 min). The most important parameter for the extraction of isoflavones from soy drinks was the sample:solvent ratio. The optimized method consists of extracting the sample with ethanol with a sample:solvent ratio of 0.2:1 on an ultrasound bath at 45 degrees C during 20 min. Also, samples were freeze-dried, extracted using conventional method and compared with the optimized method and no significant difference was observed on total and individual isoflavone concentration. The most representative samples from the Spanish market, with a wide variation of isoflavone concentration were analyzed using the optimized method. Differences between manufacturers reached an almost 10 times fold variation. Overall isoflavone concentration ranged from 6.7 to 58.2 mg L(-1).
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Affiliation(s)
- Mauricio A Rostagno
- Grupo de Investigación Químico Analítica del Vino y Productos Agroalimentarios, Departamento de Química Analitica, Facultad de Ciencias, Universidad de Cádiz, P.O. Box 40, 11510 Puerto Real, Cádiz, Spain
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26
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Wang H, Jenner AM, Lee CYJ, Shui G, Tang SY, Whiteman M, Wenk MR, Halliwell B. The identification of antioxidants in dark soy sauce. Free Radic Res 2007; 41:479-88. [PMID: 17454130 DOI: 10.1080/10715760601110871] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Soy sauce is a traditional fermented seasoning in Asian countries, that has high antioxidant activity in vitro and some antioxidant activity in vivo. We attempted to identify the major antioxidants present, using the 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assay as a guide. 3-Hydroxy-2-methyl-4H-pyran-4-one (maltol) was one of several active compounds found in an ethyl acetate extract of dark soy sauce (DSS) and was present at millimolar concentrations in DSS. However, most of the antioxidant activity was present in colored fractions, two of which (CP1 and CP2) were obtained by gel filtration chromatography. Their structural characteristics based on nuclear magnetic resonance (NMR) and electrospray-ionization time-of-flight mass spectrometry (ESI-TOF-MS) analysis suggest that carbohydrate-containing pigments such as melanoidins are the major contributors to the high antioxidant capacity of DSS.
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Affiliation(s)
- Huansong Wang
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, 8 Medical Drive, 117597 Singapore
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Lee CYJ, Isaac HB, Wang H, Huang SH, Long LH, Jenner AM, Kelly RP, Halliwell B. Cautions in the use of biomarkers of oxidative damage; the vascular and antioxidant effects of dark soy sauce in humans. Biochem Biophys Res Commun 2006; 344:906-11. [PMID: 16631617 DOI: 10.1016/j.bbrc.2006.03.217] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2006] [Accepted: 03/30/2006] [Indexed: 10/24/2022]
Abstract
Dark soy sauce (DSS) is a powerful antioxidant in vitro. We investigated whether this effect could occur in vivo and improve vascular function. Healthy human subjects were given DSS or placebo meals in a randomized, crossover study. Blood and urine were sampled before and 1, 2, 3, and 4h after the meal for F(2)-isoprostanes (total, free, and esterified) and 8OHdG measurements. Blood pressure, vascular augmentation index (AIx), and heart rate (HR) were also measured. Plasma total F(2)-isoprostanes significantly decreased 3h after placebo and the decrease was greater for DSS. Plasma free and esterified F(2)-isoprostanes were also significantly decreased after DSS. Both placebo and DSS meals increased urinary F(2)-isoprostanes at 1h but not thereafter, and lowered urinary 8OHdG levels, DBP and AIx, and increased HR. We conclude that DSS decreases lipid peroxidation in vivo. However, oxidative damage biomarkers changed after the placebo meal, a phenomenon to consider when designing interventional studies.
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Affiliation(s)
- Chung-Yung J Lee
- National University of Singapore, Yong Loo Lin School of Medicine, Department of Biochemistry, 8 Medical Drive, Singapore 117597, Singapore
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28
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Prabhakaran MP, Perera CO, Valiyaveettil S. Quantification of Isoflavones in Soymilk and Tofu from South East Asia. INTERNATIONAL JOURNAL OF FOOD PROPERTIES 2005. [DOI: 10.1081/jfp-200048055] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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29
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Setchell KDR, Cole SJ. Variations in isoflavone levels in soy foods and soy protein isolates and issues related to isoflavone databases and food labeling. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2003; 51:4146-55. [PMID: 12822960 DOI: 10.1021/jf026199b] [Citation(s) in RCA: 93] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The reliability of databases on the isoflavone composition of foods designed to estimate dietary intakes is contingent on the assumption that soy foods are consistent in their isoflavone content. To validate this, total and individual isoflavone compositions were determined by HPLC for two different soy protein isolates used in the commercial manufacture of soy foods over a 3-year period (n = 30/isolate) and 85 samples of 40 different brands of soy milks. Total isoflavone concentrations differed markedly between the soy protein isolates, varying by 200-300% over 3 years, whereas the protein content varied by only 3%. Total isoflavone content varied by up to 5-fold among different commercial soy milks and was not consistent between repeat purchases. Whole soybean milks had significantly higher isoflavone levels than those made from soy protein isolates (mean +/- SD, 63.6 +/- 21.9 mg/L, n = 43, vs 30.2 +/- 5.8 mg/L, n = 38, respectively, p < 0.0001), although some isolated soy protein-based milks were similar in content to "whole bean" varieties. The ratio of genistein to daidzein isoflavone forms was higher in isolated soy protein-based versus "whole bean" soy milks (2.72 +/- 0.24 vs 1.62 +/- 0.47, respectively, p < 0.0001), and the greatest variability in isoflavone content was observed among brands of whole bean soy milks. These studies illustrate large variability in the isoflavone content of isolated soy proteins used in food manufacture and in commercial soy milks and reinforce the need to accurately determine the isoflavone content of foods used in dietary intervention studies while exposing the limitations of food databases for estimating daily isoflavone intakes.
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Affiliation(s)
- Kenneth D R Setchell
- Division of Clinical Mass Spectrometry, Department of Pediatrics, Children's Hospital Medical Center, Cincinnati, Ohio 45229, USA.
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Abstract
Analytical strategies dealing with bioactive phenols in plants and foods are reviewed. These depend on the purpose of the analysis which may be classified as studies where the principal purpose is biological screening, phytochemical and/or chemical screening. Nevertheless, extraction of the phenol from the sample matrix is common and methods of achieving a suitable extract are assessed. Advances in the separation sciences and spectrometry are exploited for identification and quantification of isolated phenols. The various procedures are summarized and some typical "case studies" are presented. Two important areas are introduced briefly. Thus, plant phenols are reactive species and their ultimate fate has been relatively neglected. Studies of bioactive compounds generate a considerable volume of data making data handling and informatics important topics that warrant a separate review.
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Affiliation(s)
- Kevin Robards
- School of Science and Technology, Charles Sturt University, Locked Bag 588, Wagga Wagga, NSW 2678, Australia.
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31
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Huang TC, Fu HY, Ho CT. Comparative studies on some quality attributes of firm tofu sterilized with traditional and autoclaving methods. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2003; 51:254-9. [PMID: 12502417 DOI: 10.1021/jf0206419] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
An innovative retort cooking method was developed for firm tofu sterilization to replace the traditional hydrogen peroxide treatment. The caramelized firm tofu was sterilized by autoclaving at 105 degrees C for 20 min, which led to a 3 log cycle reduction of total plate count. Shelf life of the processed firm tofu was extended at least 3 months. As compared with chemical treatment, thermal treatment degraded total and individual isoflavones to a lesser extent, and only minor changes were observed. The percent DPPH free radical scavenging capacity of autoclaved firm tofu was significantly higher than that of the hydrogen peroxide treated samples. Even after prolonged heat treatment, the three-dimensional network structure of the autoclaved firm tofu did not change significantly. Texture profile analysis and sensory evaluation confirmed autoclaved firm tofu to be acceptable.
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Affiliation(s)
- Tzou-Chi Huang
- Department of Food Science, National Pingtung University of Science and Technology, Taiwan.
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Krenn L, Unterrieder I, Ruprechter R. Quantification of isoflavones in red clover by high-performance liquid chromatography. J Chromatogr B Analyt Technol Biomed Life Sci 2002; 777:123-8. [PMID: 12270205 DOI: 10.1016/s1570-0232(02)00079-x] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
An RP-HPLC method for the determination of daidzein, genistein, formononetin and biochanin A in red clover (Trifolium pratense L.) was developed and validated. The compounds are quantified after hydrolytic extraction using an internal standard. On a base-deactivated C(18) column good separation of the analytes, also from accompanying substances, and excellent peak shape are achieved by gradient elution with aqueous sulfuric acid and acetonitrile. The method was applied to the analysis of different red clover cultivars.
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Affiliation(s)
- Liselotte Krenn
- Institute of Pharmacognosy, University of Vienna, Althanstrasse 14, A-1090, Vienna, Austria.
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Wilkinson AP, Wähälä K, Williamson G. Identification and quantification of polyphenol phytoestrogens in foods and human biological fluids. J Chromatogr B Analyt Technol Biomed Life Sci 2002; 777:93-109. [PMID: 12270203 DOI: 10.1016/s1570-0232(02)00095-8] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
We review the methods used to measure phytoestrogens (genistein, daidzein, lignans and their derivatives) in foods and biological fluids, and discuss advantages and disadvantages of each. The range of detection limits reported varies widely between individual laboratories, but generally the best reported sensitivity is as follows: immunoassay>HPLC-mass spectrometry=HPLC-multichannel electrochemical detection (coularray)>GC-single ion monitoring-mass spectrometry>HPLC-UV diode array>HPLC-single channel electrochemical detection. The best sensitivity reported so far is 0.002 pmol per assay for daidzein by radioimmunoassay. HPLC with UV diode array detection is the most commonly employed, but is the least sensitive and specific. GC and HPLC coupled with mass spectrometry or electrochemical detection are the most accurate and reproducible methods for a wide variety of analytes. Generally most methods, with the exception of immunoassay, have not been correlated with other methods. Recoveries from extraction methods, limits of detection, nature of compounds analysed and the internal standards used are summarised for more than 90 reports in the literature. From this data, it is clear that an inter-laboratory validation and correlation between a wide range of methods for phytoestrogen analysis is required. One underdeveloped area that requires particular attention is the analysis of plant lignans.
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Affiliation(s)
- A P Wilkinson
- Institute of Food Research, Norwich Research Park, Norwich NR4 7UA, Colney, UK. andrew.
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