Advances in the Metabolic Mechanism and Functional Characteristics of Equol
Abstract
:1. Introduction
2. Physicochemical Properties of Equol
3. Metabolism and Absorption of Equol
3.1. Metabolism and Regulatory Mechanism of Equol
3.2. Factors Affecting the Absorption of Equol
4. Production Method of Equol
4.1. Chemical Synthesis of Equol
4.2. Microbial Preparation of Equol
4.2.1. Independent Equol-Producing Bacteria
4.2.2. Non-Independent Equol-Producing Bacteria
4.3. Biological Synthesis of Equol
5. Biological Function and Application of Equol
5.1. Hormone-like Effects
5.2. Antioxidant Activity
5.3. Other Biological Functions
6. Detection Method of Equol
7. Conclusions and Prospect
Author Contributions
Funding
Data Availability Statement
Conflicts of Interest
References
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Key Steps | Precursor | Number of Steps | Overall Yield | References |
---|---|---|---|---|
Reduction reaction | Daidzein | 1 | 61% b | [32] |
Evans alkylation | Benzyl chlorides | 6 | 9.8% | [33] |
Diels–Alder reaction | o-Quinone methides and aryl-substituted enol ethers | 3 a | 30.75% b | [34] |
Friedel–Crafts acylation reaction | M-methoxyphenol and p-hydroxyphenylacetic acid | 4 | 22.3% b | [35] |
Wittig reaction | Resorcinol | 7 | 31.0% b | [36] |
Allylic substitution | Ethyl L-(-)-lactate | 11 | 31.6% | [37] |
Reduced in a enanti-oselective manner | Daidzein | 4 | 44.46% | [38] |
Asymmetric hydrogenation | α-arylcinnamic acids | 6 | 48.4% | [39] |
Substrate | Product | Bacterial Strains | Origins | Conversion Efficiency/Time | Classifications | References |
---|---|---|---|---|---|---|
Group I | ||||||
Daidzein | DHD | |||||
HGH6 | Human | 9.3%/7 d | Clostridium | [65] | ||
Niu-O16 | Bovine | 100%/40 h | Lactobacillus | [66] | ||
TM-40 | Human | 61.1%/24 h | Coprobacillus | [67] | ||
AUH-JLR41 | Rabbit | NA | Slackia equolifaciens | [68] | ||
HXBM408 | Pregnant horse | NA | Pediococcus acidilactici | [69] | ||
Group II | ||||||
Daidzein | Equol | |||||
- | Human | NA | Bifidobacterium | [70] | ||
Pure culture | Bifidobacterium animalis | |||||
EP | Human | NA | Veillonella | [28] | ||
EPI1 | Enterococcus faecium | |||||
EPI3 | Finegoldia magna | |||||
EPI2 | Lactobacillus mucosae | |||||
AHU1763 | Rat | NA | Asaccharobacter celatus | [47] | ||
zx-5, zx-7 | Suzhong sows | NA | Clostridium bifermentans | [71] | ||
20-92 | Human | 89.4%/1 h | Lactococcus garvieae | [51] | ||
FJC-B9 | Human | NA | Adlercreutzia equolifaciens | [72] | ||
YY7918 | Human | 100%/72 h | Eggerthella | [73] | ||
do03 | Rat | 17%/96 h | Asaccharobacter celatus | [74] | ||
LH-52 | Rat | NA | Proteus mirabilis | [63] | ||
MT1B8 | Mouse | 100%/18 h | Enterorhabdus mucosicola | |||
AUH-JLM455 | Mouse | NA | Acinetobacter sp. (Patent) | [75] | ||
D1/D2 | Pig | 1.75%/48 h | Eubacterium | [48] | ||
JCM1123(T) | Mouse | NA | Lactobacillus collinoides | [76] | ||
HE8 | Human | 61.9%/14 h | Slackia isoflavoniconvertens | [77] | ||
22 strains | NA | Bifidobacterium | [78] | |||
DZE | 85.6%/120 h | Slackia equolifaciens | [79] | |||
NATTS | ≥90%/8 h | Slackia | [80] | |||
ATCC9338 | Mouse | NA | Lactobacillus fermentum | [81] | ||
ATCC15700 | Human | 78.5%/96 h | Bifidobacterium breve | [82] | ||
BB536 | 77.2%/96 h | Bifidobacterium longum | ||||
HY-1 | Human | NA | Enterococcus faecium | [83] | ||
HY-2 | Slackia isoflavoniconvert ens | |||||
AUH-Julong365 | Human | NA | Eggerthella | [84] | ||
SNR | Stinky tofu | 12~90%/24 h | Coriobacteriaceae | [50] | ||
TM-30 | Human | 52%/72 h | Coriobacteriaceae | [85] | ||
C1 | Chicken | NA | Clostridium | [86] | ||
CS1 | Human | NA | Pediococcus pentosaceus | [56] | ||
CS2(JS1) | Lactobacillus paracasei | |||||
CS3 | Lactobacillus sakei/graminis | |||||
JCM 7548 | Rat | 29.5%/48 h | Lactobacillus intestinalis | [64] | ||
Y11 | Human | 56%/120 h | Slackia equiolifaciens | [87] | ||
DHD | Equol | |||||
SNU Julong 732 | Human | >80%/96 h | Eggerthella | [42] | ||
FJC-A10/FJC-A161 | Human | NA | Adlercreutzia equolifaciens | [72] | ||
Group III | ||||||
Daidzein | O-DMA | |||||
HGH 136 | Human | NA | Clostridium | [61] | ||
wK1 | Human | NA | Eubacterium ramulus | [88] | ||
AUH-HM195 | Brown pheasant | NA | Enterococcus hirae | [62] | ||
AUH-JLC108 | Chicken | 80%/24 h | Clostridium | [89] | ||
AUH-JLC140 | Chicken | NA | Clostridium | [90] |
Detection Methods | Principle | Advantages | Disadvantages |
---|---|---|---|
HPLC | Separation is carried out by taking advantage of the difference in the distribution of analytes with mobile and stationary phases. | High sensitivity, high flow rate, high separation efficiency, suitable for macromolecules, thermally unstable substances | Long analysis time, low resolution, and short column lifetime |
MS | Analyze by measuring the mass-to-charge ratio of the tested sample ions. | Good specificity, high sensitivity and fast analysis | High cost, the complex preparation and labor-intensive sample preparation |
UV-Vis | Molecules and ions in a substance are used to absorb light in its wavelength range. | Easy operation, high accuracy, fast detection speed, low measurement cost | Poor characterization and limitations of qualitative analysis |
ELISA | Assay using the color displayed after the analyte reacts with the enzyme. | Simple operation, good reproducibility and high sensitivity | Sometimes nonspecific reactions occur |
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Gong, Y.; Lv, J.; Pang, X.; Zhang, S.; Zhang, G.; Liu, L.; Wang, Y.; Li, C. Advances in the Metabolic Mechanism and Functional Characteristics of Equol. Foods 2023, 12, 2334. https://doi.org/10.3390/foods12122334
Gong Y, Lv J, Pang X, Zhang S, Zhang G, Liu L, Wang Y, Li C. Advances in the Metabolic Mechanism and Functional Characteristics of Equol. Foods. 2023; 12(12):2334. https://doi.org/10.3390/foods12122334
Chicago/Turabian StyleGong, Yining, Jiaping Lv, Xiaoyang Pang, Shuwen Zhang, Guofang Zhang, Libo Liu, Yunna Wang, and Chun Li. 2023. "Advances in the Metabolic Mechanism and Functional Characteristics of Equol" Foods 12, no. 12: 2334. https://doi.org/10.3390/foods12122334
APA StyleGong, Y., Lv, J., Pang, X., Zhang, S., Zhang, G., Liu, L., Wang, Y., & Li, C. (2023). Advances in the Metabolic Mechanism and Functional Characteristics of Equol. Foods, 12(12), 2334. https://doi.org/10.3390/foods12122334