Dietary isoflavones and intestinal microbiota: Metabolism and transformation into bioactive compounds

Isoflavones: Biosynthesis, Occurrence and Health Effects

Volumn , Issue , 2010, Pages 137-162

  Rossi, Maddalena ^a   Amaretti, Alberto ^a   Roncaglia, Lucia ^a   Leonardi, Alan ^a   Raimondi, Stefano ^a  

^a UNIVERSITY OF MODENA AND REGGIO EMILIA   (Italy)

Author keywords

[No Author keywords available]

Indexed keywords

EID: 82455200929     PISSN: None     EISSN: None     Source Type: Book    
DOI: None     Document Type: Chapter

References (115)

1. Aminov, RI; Walker, AW; Duncan, SH; Harmsen, HJM; Welling, GW; Flint, HJ. Molecular diversity, cultivation, and improved detection of fluorescent in situ hybridisation of a dominant group of human gut bacteria related to Roseburia spp. or Eubacterium rectale. Appl Environ Microbiol, 2006, 72, 6371-6376.
2. Arora, A; Nair, MG; Strasburg, GM. Antioxidant activities of isoflavones and their biological metabolites in a liposomal system. Arch Biochem Biophys, 1998, 356, 133-141.
3. Atkinson, C; Berman, S; Humbert, O; Lampe, JW. In vitro incubation of human feces with daidzein and antibiotics suggests interindividual differences in the bacteria responsible for equol production. J Nutr, 2004, 134, 596-599.
4. Atkinson, C; Frankenfeld, CL; Lampe, JW. Gut bacterial metabolism of the soy isoflavone daidzein: exploring the relevance to human health. Exp Biol Med, 2005, 230, 155-170.
5. Aura, AM. Microbial metabolism of dietary phenolic compounds in the colon. Phytochem Rev, 2008, 7, 407-429.
6. Bae, EA; Park, SY; Kim, DH. Constitutive beta-glucosidases hydrolyzing ginsenoside Rb1 and Rb2 from human intestinal bacteria. Biol Pharm Bull, 2000, 23, 1481-1485.
7. Bae, EA; Han, MJ; Choo, MK; Park, SY; Kim, DH. Metabolism of 20(S), and 20(R)-ginsenoside Rg3 by human intestinal bacteria and its relation to in vitro biological activities. Biol Pharm Bull, 2002, 25, 58-63.
8. Bae, EA; Han, MJ; Kim, EJ; Kim, DH. Transformation of ginseng saponins to ginsenoside Rh2 by acids and human intestinal bacteria and biological activities of their transformants. Arch Pharm Res, 2004, 27, 61-67.
9. Banerjee, S; Li, Y; Wang, Z; Sarkar, FH. Multi-targeted therapy of cancer by genistein. Cancer Lett, 2008, 269, 226-242.
10. Batterham, TJ; Hart, NK; Lamberton, JA; Braden AWH. Metabolism of Oestrogenic Isoflavones in Sheep. Nature, 1965, 206, 509.
11. Batterham, TJ; Shutt, DA; Hart, NK; Braden, AWH; Tweeddale, HJ. Metabolism of intraruminally administered [4-14C]formononetin and [4-14C]biochanin a in sheep. Australian Journal of Agricultural Research, 1971, 22(1), 131-138.
12. Blaut, M; Schoefer, L; Braune, A. Transformation of flavonoids by intestinal microorganisms. Int J Vitam Nutr Res, 2003, 73(2), 87-79.
13. Bokkenheuser, VD; Suzuki, JB; Polovsky, SB; Winter, J; Kelly, WG. Metabolism of deoxycorticosterone by human fecal flora. Appl Microbiol, 1975, 30, 82-90.
14. Bowey, E; Adlercreutz, H; Rowland, I. Metabolism of isoflavones and lignans by the gut microflora: a study in germ-free and human flora associated rats. Food Chem Toxicol, 2003, 41, 631-636.
15. Cederroth, CR; Nef, S. Soy, phytoestrogens and metabolism: A review. Mol Cell Endocrinol, 2009, 304, 30-42.
16. Chang, Y; Nair, GN. Metabolism of daidzein and genistein by intestinal bacteria. J Nat Prod, 1995, 58(12), 1892-1896.
17. Cheng, DL; Hashimoto, K; Uda, Y. In vitro digestion of sinigrin and glucotropaeolin by single strains of Bifidobacterium and identification of the digestive products. Food Chem Toxicol, 2004, 42, 351-357.
18. Chun, J; Kim, G; Lee, K; Choi, ID; Know, GH; Park, JY; Jeong, SJ; Kim, JS; Kim, JH. Conversion of Isoflavone Glucosides to Aglycones in Soymilk by Fermentation with Lactic Acid Bacteria. Journal of Food Science, 2007, 72, M39-44.
19. Clavel, T; Borrmann, D; Braune, A; Doré, J; Blaut, M. Occurrence and activity of human intestinal bacteria involved in the conversion of dietary lignans. Anaerobe, 2006a, 12, 140-147.
20. Clavel, T; Henderson, G; Engst, W; Doré, J; Blaut, M. Phylogeny of human intestinal bacteria that activate the dietary lignan secoisolariciresinol diglucoside. FEMS Microbiol Ecol, 2006b, 55, 471-478.
21. Coldham, NG; Howells, LC; Santi, A; Montesissa, C; Langlais, C; King, LJ; Macpherson, DD; Sauer, MJ. Biotransformation of genistein in the rat: elucidation of metabolite structure by product ion mass fragmentology. Journal of Steroid Biochemistry and Molecular Biology, 1999, 70, 169-184.
22. Coldham, NG; Darby, C; Hows, M; King, LJ; Zhang, AQ; Sauer, MJ. Comparative metabolism of genistin by human and rat gut microflora: detection and identification of the end-products of metabolism. Xenobiotica, 2002 32(1), 45-62.
23. Collins, MD; Lawson, PA; Willems, A; Cordoba, JJ; Fernandez-Garayzabal, J; Garcia, P; Cai, J; Hippe, H; Farrow, JAE. The phylogeny of the genus Clostridium: proposal of five new genera and eleven new species combinations. Int J Syst Bacteriol, 1994, 44, 812-826.
24. Crozier, A; Jaganath, IB; Clifford, MN. Dietary phenolics: chemistry, bioavailability and effects on health. Nat Prod Rep, 2009, 26(8), 1001-43.
25. Cummings, JH; Macfarlane, GT; Englyst, HN. Prebiotic digestion and fermentation. Am J Clin Nutr, 2001, 73, 415S-420S.
26. Dabek, M; Sheila I. McCrae, SI; Stevens, VJ; Duncan, SH; Louis, P. Distribution of β-glucosidaseand and β-glucuronidase activity and of β-glucuronidase gene gus in human colonic bacteria. FEMS Microbiol Ecol, 2008, 66, 487-495.
27. Decroos, K; Vanhemmens, S; Cattoir, S; Boon, N; Verstraete, W. Isolation and characterization of an equol-producing mixed microbial culture from a human fecal sample and its activity under gastrointestinal conditions. Arch Microbiol, 2005, 183, 45-55.
28. Dixon, RA; Ferreira, D. Molecules of Interest, Genistein. Phytochemistry, 2002, 60, 205-211.
29. Duncan, SH; Barcenilla, A; Stewart, CS; Pryde, SE; Flint, HJ. Acetate utilization and butyryl coenzyme A (CoA): acetate-CoA transferase in butyrate-producing bacteria from the human large intestine. Appl Environ Microbiol, 2002, 68, 5186-5190.
30. Eckburg, PB; Bik, EM; Bernstein, CN; Purdom, E; Dethlefsen, L; Sargent, M; Gill, SR; Nelson, KE; Relman, DA. Diversity of the human intestinal microbial flora. Science,, 2005, 308(5728), 1635-8.
31. Franke, AA; Custer, LJ; Cerna, CM; Narala, K. Rapid HPLC analysis of dietary phytestrogens from legumes and from human urine. Proc Soc Exp Biol Med, 1995, 208(1), 18-26.
32. French, CE; Bruce, NC. Bacterial morphinone reductase is related to old yellow enzyme. Biochem J, 1995, 312, 671-678.
33. Gibson, GR; Roberfroid, MB. Dietary modulation of the human colonic microbiotaintroducing the concept of prebiotics. J Nutr, 1995, 125, 1401-1412.
34. Griffiths, LA; Smith, GE. Metabolism of Apigenin and Related Compounds in the Rat. Biochem J, 1972, 128, 901-911.
35. Harmsen, HJ; Raangs, GC; He, T; Degener, JE; Welling, GW. Extensive set of 16S rRNAbased probes for detection of bacteria in human feces. Appl Environ Microbiol, 2002, 68, 2982-2990.
36. He, X; Lin, L; Lian, L. Analysis of flavonoids from red clover by liquid chromatographyelectrospray mass spectrometry. J Chromatogr A, 1996, 755, 127-132.
37. Heinonen, SM; Wähälä, K; Adlercreutz, H. Identification of Isoflavone Metabolites Dihydrodaidzein, Dihydrogenistein, 6'-OH-O-dma, and cis-4-OH-equol in Human Urine by Gas Chromatography-Mass Spectroscopy Using Authentic Reference Compounds. Analytical Biochemistry, 1999, 274, 211-219.
38. Heinonen, SM; Hoikkala, A; Wähälä, K; Adlercreutz, H. Metabolism of the soy isoflavones daidzein, genistein and glycitein in human subjects. Identification of new metabolites having an intact isoflavonoid skeleton. J Steroid Biochem Mol Biol, 2003, 87, 285-299.
39. Heinonen, SM; Wähälä, K; Adlercreutz, H. Identification of Urinary Metabolites of the Red Clover Isoflavones Formononetin and Biochanin A in Human Subjects. J Agric Food Chem, 2004a, 52, 6802-6809.
40. Heinonen, SM; Wähälä, K; Liukkonen, KH; Aura, AM; Poutanen, K; Adlercreutz, H. Studies of the In Vitro Intestinal Metabolism of Isoflavones Aid in the Identification of Their Urinary Metabolites. J Agric Food Chem, 2004b, 52, 2640-2646.
41. Hopkins, MJ; Macfarlane, GT. Nondigestible oligosaccharides enhance bacterial colonization resistance against Clostridium difficile in vitro. Appl Environ Microbiol, 2003, 69, 1920-1927.
42. Hur, HG; Lay, Jr. JO; Beger, RD; Freeman, JP; Rafii, F. Isolation of human intestinal bacteria metabolizing the natural isoflavone glycosides daidzin and genistin. Arch Microbiol, 2000, 174, 422-428.
43. Hur, HG; Rafii, F. Biotransformation of the isoflavonoids biochanin A, formononetin, and glycitein by Eubacterium limosum. FEMS Microbiology Letters, 2000, 192, 21-25.
44. Hur, HG; Beger, RD;Heinze, TM; Lay Jr, JO; Freeman, JP; Dore, J; Rafii, F. Isolation of an Anaerobic Intestinal Bacterium Capable of Cleaving the C-ring of the Isoflavonoid Daidzein. Arch Microbiol, 2002, 178, 8-12.
45. Iqbal, MF; Zhu, WY. Characterization of newly isolated Lactobacillus delbrueckii-like strain MF-07 isolated from chicken and its role in isoflavone biotransformation. FEMS Microbiol Lett, 2009, 291, 180-187.
46. Jin, JS; Nishihata, T; Kakiuchi, N; Hattori, M. Biotransformation of C-Glucosylisoflavone Puerarin to Estrogenic (3S)-Equol in Co-culture of Two Human Intestinal Bacteria. Biol Pharm Bull, 2008 31(8), 1621-1625.
47. Joannou, GE; Kelly, GE; Reeder, AY; Waring, M; Nelson, C. A urinary profile study of dietary phytestrogens. the identification and mode of metabolism of new isoflavonoids. J Steroid Biochem Mol Biol, 1995, 54, 167-184.
48. Kelly, GE; Nelson, C; Waring, MA; Joannou, GE; Reeder, AY. Metabolites of dietary (soya) isoflavones in human urine. Clin Chim Acta, 1993, 223, 9-22.
49. Kim, DH; Yu, KU; Bae, EA; Han, MJ. Metabolism of puerarin and daidzin by human intestinal bacteria and their relation to in vitro cytotoxicity. Biol Pharm Bull, 1998, 21(6), 628-30.
50. Kim, M; Kim, SI; Han, J; Wang, XL; Song, DG; Kim, SU. Stereospecific biotransformation of dihydrodaidzein into (3S)-equol by the human intestinal bacterium Eggerthella strain Julong 732. Appl Environ Microbiol, 2009, 75, 3062-3068.
51. Klejdus, B; Vitamvasova-Sterbova, D; Kuban, V. Identification of isoflavone conjugates in red clover (Trifolium pratense) by liquid chromatography-mass spectrometry after twodimensional solid-phase extraction. Anal Chim Acta, 2001, 450, 81-97.
52. Kris-Etherton, PM; Hecker, KD; Bonanome, A; Coval, SM; Binkoski, AE; Hilpert, KF; Griel, AE; Etherton, TD. Bioactive compounds in foods: their role in the prevention of cardiovascular disease and cancer. Am J Med, 2002 113, 71S-88S.
53. Kuiper, GGJM; Lemmen, JG; Carlsson, B; Corton, JC; Safe, SH; Saag, PTVD; Burg, BVD; Gustafsson, JA. Interaction of estrogenic chemicals and phytestrogens with estrogen receptor. L. Endocrinology, 1998, 139, 4252-4263.
54. Lampe, JW; Karr, SC; Hutchins, AM; Slavin, JL. Urinary equol excretion with a soy challenge: influence of habitual diet. Proc Soc Exp Biol Med, 1998, 217(3), 335-339.
55. Lampe, JW; Skor, HE; Li, S; Wähälä, K; Howald, WN; Chen, C. Wheat bran and soy protein feeding do not alter urinary excretion of the isoflavon equol in premenopausal women. J Nutr, 2001, 131, 740-744.
56. Leser, TD; Mølbak L. Better living through microbial action: the benefits of the mammalian gastrointestinal microbiota on the host. Environ Microbiol, 2009, 11, 2194-2206.
57. Lu, LJ; Lin, SN; Grady, JJ; Nagamani, M; Anderson, KE. Altered kinetics and extent of urinary daidzein and genistein excretion in women during chronic soya exposure. Nutr Cancer, 1996, 26(3), 289-302.
58. Manach, C; Scalbert, A; Morand, C; Rémésy, C; Jiménez, L. Polyphenols: food sources and bioavailability. Am J Clin Nutr, 2004, 79, 727-747.
59. Mariat, D; Firmesse, O; Levenez, F; Guimarǎes, V; Sokol, H; Doré, J; Corthier, G; Furet, JP. The Firmicutes/Bacteroidetes ratio of the human microbiota changes with age. BMC Microbiol, 2009, 9, 123.
60. Maruo, T; Sakamoto, M; Ito, C; Toda, T; Benno, Y. Adlercreutzia equolifaciens gen. nov., sp. nov., an equol-producing bacterium isolated from human faeces, and emended description of the genus Eggerthella. Int J Syst Evol Microbiol, 2008, 58, 1221-1227.
61. Matthies, A; Clavel, T; Gütschow, M; Engst, W; Haller, D; Blaut, M; Braune, A. Conversion of daidzein and genistein by a newly isolated anaerobic bacterium from mouse intestine. Appl Environ Microbiol, 2008, 74, 4847-4852.
62. Matthies, A; Blaut, M; Braune, A. Isolation of a human intestinal bacterium capable of daidzein and genistein conversion. Appl Environ Microbiol, 2009, 75, 1740-1744.
63. Marotti, I; Bonetti, A; Biavati, B; Catizone, P; Dinelli, G. Biotransformation of common bean (Phaseolus vulgaris L.) flavonoid glycosides by Bifidobacterium species from human intestinal origin. J Agric Food Chem, 2007, 55, 3913-3919.
64. McBain, AJ; Macfarlane, GT. Ecological and physiological studies on large intestinal bacteria in relation to production of hydrolytic and reductive enzymes involved in formation of genotoxic metabolites. J Med Microbiol, 1998, 47, 407-416.
65. McMahon, LG; Nakano, H; Levy, MD; Gregory, JF 3rd. Cytosolic pyridoxine β-D-glucoside hydrolase from porcine jejunal mucosa. Purification, properties and comparison with broad specificity b-glucosidase. J Biol Chem, 1997, 272, 32025-32033.
66. McMullen, MH; Hamilton-Reeves, JM; Bonorden, MJ; Wangen, KE; Phipps, WR; Feirtag, JM; Kurzer, MS. Consumption of Lactobacillus acidophilus and Bifidobacterium longum does not alter phytestrogen metabolism and plasma hormones in men: a pilot study. J Altern Complement Med, 2006, 12, 887-94.
67. Minamida, K; Tanaka, M; Abe, A; Sone, T; Tomita, F; Hara, H; Asano, K. Production of equol from daidzein by gram-positive rod-shaped bacterium isolated from rat intestine. J Biosci Bioeng, 2006, 102(3), 247-250.
68. Minamida, K; Ota, K; Nishimukai, M; Tanaka, M; Abe, A; Sone, T; Tomita, F; Hara, H; Asano, K. Asaccharobacter celatus gen. nov., sp. nov., isolated from rat caecum. Int J Syst Evol Microbiol, 2008, 58, 1238-1240.
69. Mueller, S; Saunier, K; Hanisch, C; Norin, E; Alm, L; Midtvedt, T; Cresci, A; Silvi, S; Orpianesi, C; Verdenelli, MC; Clavel, T; Koebnick, C; Zunft, HJ; Doré, J; Blaut, M. Differences in fecal microbiota in different European study populations in relation to age, gender, and country: a cross-sectional study. Appl Environ Microbiol, 2006, 72, 1027-1033.
70. Nakamura, J; Kubota, Y; Miyaoka, M; Saitoh, T; Mizuno, F; Benno, Y. Comparison of four microbial enzymes in Clostridia and Bacteroides isolated from human feces. Microbiol Immunol, 2002, 46, 487-490.
71. Nielsen, SE; Breinholt, V; Cornett, C; Dragsted, LO. Biotransformation of the citrus flavone tangeretin in rats. Identification of metabolites with intact flavane nucleus. Food Chem Toxicol, 2000, 38(9), 739-46.
72. O'Keefe, SJ. Nutrition and colonic health: the critical role of the microbiota. Curr Opin Gastroenterol, 2008, 24(1), 51-8.
73. O'Keefe, SJ; Ou, J; Aufreiter, S; O'Connor, D; Sharma, S; Sepulveda, J; Fukuwatari, T; Shibata, K; Mawhinney, T. Products of the colonic microbiota mediate the effects of diet on colon cancer risk. J Nutr, 2009, 139(11), 2044-8.
74. Park, EK; Shin, J; Bae, EA; Lee, YC; Kim, DH. Intestinal bacteria activate estrogenic effect of main constituents puerarin and daidzin of Pueraria thunbergiana. Biol. Pharm Bull, 2006, 29, 2432-2435.
75. Rafii, F; Jackson, LD; Ross, I; Heinze, TM; Lewis, SM.; Aidoo, A; Lyn-Cook, L; Manjanatha, M. Metabolism of Daidzein by Fecal Bacteria in rats. Comparative Medicine, 2007, 57(3), 282-286.
76. Raimondi, S; Roncaglia, L; De Lucia, M; Amaretti, A; Leonardi, A; Pagnoni, UM; Rossi, M. Bioconversion of soy isoflavones daidzin and daidzein by Bifidobacterium strains. Appl Microbiol Biotechnol, 2009, 81, 943-950.
77. Rechner, AR; Smith, MA; Kuhnle, G; Gibson, GR; Debnam, ES; Srai, SK; Moore, KP; Rice-Evans, CA. Colonic metabolism of dietary polyphenols: influence of structure on microbial fermentation products. Free Radic Biol Med, 2004, 36, 212-225.
78. Rowland, IR; Wiseman, H; Sanders, TA; Adlercreutz, H; Bowey, EA. Interindividual variation in metabolism of soy isoflavones and lignans: influence of habitual diet on equol production by the gut microflora. Nutr Cancer, 2000, 36(1), 27-32.
79. Rüfer, CE; Glatt, H; Kulling, SE. Structural elucidation of hydroxylated metabolites of the isoflavan equol by gas chromatography-mass spectrometry and high-performance liquid chromatography-mass spectrometry. Drug Metab Dispos, 2006, 34(1), 51-60.
80. Selma, MV; Espín, JC; Tomás-Barberán, FA. Intertaction between Phenolics and Gut Microbiota: Role in Human Health. J Agric Food Chem, 2009, 57, 6485-6501.
81. Scalbert, A; Williamson, G. Dietary intake and bioavailability of polyphenols. J Nutr, 2000 130, 2073S-85S.
82. Scheline, RR. Metabolism of foreign compounds by gastrointestinal microorganisms. Pharmacol Rev, 1973, 25, 451-523.
83. Schell, MA; Karmirantzou, M; Snel, B; Vilanova, D; Berger, B; Pessi, G; Zwahlen, MC; Desiere, F; Bork, P; Delley, M; Pridmore, RD; Arigoni, F. The genome sequence of Bifidobacterium longum reflects its adaptation to the human gastrointestinal tract. Proc Natl Acad Sci, USA, 2002, 99, 14422-14427.
84. Schoefer, L; Mohan, R; Braune, A; Birringer, M; Blaut, M. Anaerobic C-ring cleavage of genistein and daidzein by Eubacterium ramulus. FEMS Microbiology Letters, 2002, 208, 197-202.
85. Setchell, KD; Borriello, SP; Hulme, P; Kirk, DN; Axelson, M. Nonsteroidal estrogens of dietary origin: possible roles in hormone-dependent disease. Am J Clin Nutr, 1984, 40, 569-78.
86. Setchell, KDR; Cassidy, A. Dietary isoflavones: biological effects and relevance to human health. J Nutr, 1999, 129, 758S-767S.
87. Setchell, KDR; Brown, NM; Desai, P; Zimmer-Nechemias, L; Wolfe, BE; Brashear, WT; Kirschner, AS; Cassidy, A; Heubi, JE. Bioavailability of Pure Isoflavones in Healthy Humans and Analysis of Commercial Soy Isoflavone Supplements. J. Nutr, 2001, 131, 1362S-1375S.
88. Setchell, KD; Cole, SJ. Variations in isoflavone levels in soy foods and soy protein isolates and issues related to isoflavone databases and food labeling. J Agric Food Chem, 2003, 51, 4146-4155.
89. Setchell, KD; Clerici, C; Lephart, ED; Cole, SJ; Heenan, C; Castellani, D; Wolfe, BE; Nechemias-Zimmer, L; Brown, NM; Lund, TD; Handa, RJ; Heubi, JE. S-equol, a potent ligand for estrogen receptor beta, is the exclusive enantiomeric form of the soy isoflavone metabolite produced by human intestinal bacterial flora. Am J Clin Nutr., 2005, 81(5), 1072-1079.
90. Setchell, KD; Zhao, X; Shoaf, SE; Ragland, K. The pharmacokinetics of S-(-)equol administered as SE5-OH tablets to healthy postmenopausal women. J Nutr, 2009, 139(11), 2037-2043.
91. Simons, AL; Renouf, M; Hendrich, S; Murphy, PA. Metabolism of Glycitein (7, 4'-Dihydroxy-6-methoxy-isoflavone) by Human Gut Microflora. J Agric Food Chem, 2005, 53, 8519-8525.
92. Song, TT; Barua, K; Buseman, G; Murphy, PA. Isoflavone analysis: New internal standard and quality control. Am J Clin Nutr, 1998, 68, 1474S-1479S.
93. Song, TT; Hendrich, S; Murphy, PA. Estrogenic activity of glycitein, a soy isoflavon. J Agric Food Chem, 1999, 47, 1607-1610. Erratum J Agric Food Chem, 2002, 50, 2470.
94. Steer, TE; Johnson, IT; Gee, JM; Gibson, GR. Metabolism of the soyabean isoflavone glycoside genistin in vitro by human gut bacteria and the effect of prebiotics. British Journal of Nutrition, 2003 90, 635-642.
95. Tamura, M; Tsushida, T; Shinohara, K. Isolation of an isoflavone-metabolizing, Clostridiumlike bacterium, strain TM-40, from human faeces. Anaerobe, 2007, 13, 32-35.
96. Tan, Y; Liu, M; Wu, B. Puerarin for acute ischaemic stroke. Cochrane Database Syst Rev, 2008, 23(1), CD004955.
97. Tsangalis, D; Ashton, JF; McGill, AEJ; Shah, NP. Enzymic transformation of isoflavone phytestrogens in soymilk by β-glucosidase-producing bifidobacteria. J Food Sci, 2002, 67, 3104-3113.
98. Tsangalis, D; Wilcox, G; Shah, NP; McGill, AE; Stojanovska, L. Urinary excretion of equol by postmenopausal women consuming soymilk fermented by probiotic bifidobacteria. Eur J Clin Nutr, 2007, 61, 438-441.
99. Uehara, M; Ohta, A; Sakai, K; Suzuki, K; Watanabe, S; Adlercreutz, H. Dietary Fructooligosaccharides Modify Intestinal Bioavailability of a Single Dose of Genistein and Daidzein and Affect Their Urinary Excretion and Kinetics in Blood of Rats. J. Nutr., 2001, 131, 787-795.
100. Uchiyama, S; Ueno, T; Imaizumi, K; Kumemura, M; Masaki, K; Shimizu, S. Isoflavonecontaining compositions. Patent: Publication No. WO9907392, 1999.
101. Uchiyama, S; Ueno, T; Suzuki, T. Composition containing lactic acid bacterium producing equol. Patent: Publication No. WO2005000042, 2005.
102. Uchiyama, S; Ueno, T; Suzuki, T. Identification of a Newly Isolated Equol-Producing Lactic Acid Bacterium from the Human Feces. J Intestinal Microbiol, 2007, 21, 217-220.
103. Wiseman, H; Casey, K; Bowey, EA; Duffy, R; Davies, M; Rowland, IR; Lloyd, AS; Murray, A; Thompson, R; Clarke, DB. Influence of 10 wk of soy consumption on plasma concentrations and excretion of isoflavonoids and on gut microflora metabolism in healthy adults. Am J Clin Nutr, 2004, 80, 692-699.
104. Wang, XL; Hur, HG; Lee, JH; Kim, KT; Kim, SI. Enantioselective Synthesis of S-Equol from Dihydrodaidzein by a Newly Isolated Anaerobic Human Intestinal Bacterium. AEM, 2005a, 71(1), 214-219.
105. Wang, XL; Shin, KH; Hur, HG; Kim, SI. Enhanced biosynthesis of dihydrodaidzein and dihydrogenistein by a newly isolated bovine rumen anaerobic bacterium. J Biotechnol, 2005b, 115, 261-269.
106. Wang, XL; Kim, HJ; Kang, SI; Kim, SI, Hur, HG. Production of phytestrogen S-equol from daidzein in mixed colture of two anaerobic bacteria. Arch Microbiol, 2007, 187, 155-160.
107. Xu, X; Harris, KS; Wang, HJ; Murphy, PA; Hendrich, S. Bioavalability of soybean isoflavones depends upon gut microflora in women. J Nutr, 1995, 125, 2307-2315.
108. Yasuda, T; Ueda, J; Ohsawa, K. Urinary Metabolites of Genistein Administered Orally to Rats. Chem Pharm Bull, 2001, 49(11), 1495-1497.
109. Yee, S; Berdock, GA; Kurata, Y; Enomoto, Y; Narumi, K; Hamada, S; Itoh, T; Shimomura, Y; Ueno, T. Acute and subchronic toxicity and genotoxicity of SE5-OH, an equol-rich product produced by Lactococcus garvieae. Food and Chemical Toxicology, 2008, 46, 2713-2720.
110. Yokoyama, SI; Suzuki, T. Isolation and characterization of novel equol-producing bacterium from human feces. Biosci Biotechnol Biochem, 2008, 72, 2660-2666.
111. Yokoyama, S; Niwa, T; Osawa, T; Suzuki, T. Characterization of an O-desmethylangolensinproducing bacterium isolated from human feces. Arch Microbiol, 2009, 192, 15-22.
112. Yu, ZT; Yao, W; Zhu, WY. Isolation and identification of equol-producing bacterial strains from cultures of pig faeces. FEMS Microbiol Lett, 2008, 282, 73-80.
113. Yuan, JP; Wang, JH; Liu, X. Metabolism of dietary soy isoflavones to equol by human intestinal microflora-implications for health. Mol Nutr Food Res, 2007, 51, 765-781.
114. Zhang, Y; Wang, G; Song, TT; Murphy, PA; Hendrich, S. Urinary Disposition of the Soybean Isoflavones Daidzein, Genistein and Glycitein Differs among Humans with Moderate Fecal Isoflavone. J Nutr, 1999, 129, 957-962.
115. Zhang, L; Zuo, Z; and Lin, G. Intestinal and hepatic glucuronidation of flavonoids. Mol Pharm, 2007 4, 833-845.