Pueraria Flowers Research Articles

Phytochemicals and biological activities of Pueraria flower: a review

Pueraria lobata (Kudzu root) has been well documented as a food and also an herbal plant for its ability to alleviate hangover, diarrhea and cardiovascular diseases. However, the flower of Pueraria lobata has been attracted attention only in recent decades. Bioactive phytochemicals such as isoflavones, saponins, essential oils and other components have been isolated and identified in Pueraria flower extracts (PFE). Both in vivo and in vitro research have indicated the health promoting effects of Pueraria flower including hepatoprotective property, estrogenic effects, antioxidant activity, anti-inflammation activity and other pharmacological activities. In this review, we have summarized the chemical compositions and pharmacological actions of Pueraria flower and updated knowledge with recent progress.

The Protective Effects of Water Extracts of Compound Turmeric Recipe on Acute Alcoholism: An Experimental Research Using a Mouse Model.

Acute alcoholism (AAI) is a common emergency. Currently, there is a lack of preventive and therapeutic drugs with superior safety and efficacy. Curcuma longa, Panax ginseng, Pueraria lobata, Pueraria flower, and Hovenia dulcis Thunb., which are the components of compound turmeric recipe (CTR), are, respectively, used in China as adjuvant therapeutic agents for AAI and alcoholic liver injury, respectively. The purpose of this research was to investigate the effect of traditional compound turmeric recipe in anti-inebriation treatment and to identify its underlying mechanisms. The mice were administered with CTR mixture, and ethanol was subsequently given to mice by gavage. The effects of CTR on the righting reflex, 24-hour survival, drunken behavior, blood ethanol concentration, and pathological changes of liver are depicted. The activities of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP) were detected. Besides, the activities of tumor necrosis factor-α (TNF-α), interleukin-8 (IL-8), alcohol dehydrogenase (ADH), aldehyde dehydrogenase (ALDH), cytochrome P450 (P450), superoxide dismutase (SOD), and malondialdehyde (MDA) in the liver and the levels of β-endorphin (β-EP) and leucine enkephalin (LENK) in the brain were also measured. Our results demonstrated that CTR can increase the activities of ADH, ALDH, P450, and SOD and decrease the contents of TNF-α, IL-8, and MDA in the liver. In addition, it can decrease the activities of ALT, AST, and ALP in serum and β-EP and LENK activities in the brain. CTR showed effects on prevention of acute alcoholism, promoting wakefulness, and alleviating alcoholic liver injury, which were likely mediated by the above mechanisms.

Protective Effect of Pueraria Flower in the Treatment of Osteoarthritis Rat by Attenuating Inflammatory Pathway

Protective Effect of Pueraria Flower in the Treatment of Osteoarthritis Rat by Attenuating Inflammatory Pathway

Safety and Efficacy Assessment of Isoflavones from Pueraria (Kudzu) Flower Extract in Ovariectomised Mice: A Comparison with Soy Isoflavones.

Numerous Foods with Function Claims that contain the extract of Pueraria flower (kudzu) isoflavones (PFI) are available in the Japanese market. These are labelled with function claims of reducing visceral fat. However, these foods have not undergone proper safety assessment such as the evaluation of their oestrogenic activity and effects on drug-metabolising enzymes (cytochrome P-450: CYP) in the liver. This study evaluated the estrogenic effect and the hepatic CYP activity and mRNA expression in normal female mice as a safety assessment of PFI (Experiment 1). In addition, the bone mineral density and visceral fat weight in ovariectomised mice (OVX) compared to soy isoflavones (SI) was evaluated to assess the efficacy of PFI (Experiment 2). OVX control fed a control diet, OVX fed a PFI diet (the recommended human intake of PFI), OVX fed a PFI20 diet (20- times the recommended PFI), OVX fed an SI diet (the recommended human intake of SI), and OVX fed an SI20 diet (20 -times the recommended intake of SI) for 28 days in Experiment 2. Body, liver, and visceral fat weights were not affected by the PFI, PFI20, SI, or SI20 diets. The hepatic CYP1A and CYP3A activities were elevated by the SI20 treatment. Ovariectomy-induced bone loss was inhibited by the SI20 treatment, but not by the PFI20 treatment. These results suggest that (1) PFI intake in human doses had no oestrogenic properties and did not affect CYP activity in the liver; (2) there was no evidence that PFI affects the amount of visceral fat in OVX mice.

Production of vinegar using edible alcohol as feedstock through high efficient biotransformation by acetic acid bacteria.

In this paper, an optimal semi-continuous process for vinegar production from edible alcohol through biotransformation by acetic acid bacteria (AAB) WUST-01 was developed. The optimized medium composition forthe starting-up stage was glucose 5.1g/L, yeast extract 26.2g/L, and ethanol 11.9mL/L, and the optimal ethanol for the following semi-continuous stage was 50mL/L. In the semi-continuous biotransformation process, the optimal withdraw ratio was 50% of working volume with 12h cycle time. With these conditions, the total acidity could reach to 77.3g/L and the acidity productivity could reach to 3.0g/(Lh) in a 5L reactor. Furthermore, it was investigated to strengthen vinegar synthesis through enhancing alcohol dehydrogenase and aldehyde dehydrogenase activity in AAB by ferrous ion and pueraria flower extract as the enzyme regulators. With these regulators, the vinegar synthesis efficiency can be improved 16.3 and 13.2% respectively.

Anti-EndometrioticEffectsofPuerariaFlowerExtract inHumanEndometrioticCellsandMice.

Pueraria flowers have been used as a vegetable and an ingredient for tea and jelly. In this study, we investigated the effects of Pueraria flower extract (PFE) on endometriosis, a common gynaecological disease characterised by local sterile inflammation of peritoneal cavity. PFE suppressed the adhesion of human endometriotic cells 11Z and 12Z to human mesothelial Met5A cells. In addition, PFE significantly inhibited the migration of 11Z and 12Z cells as shown by wound-healing and transwell migration assays. PFE reduced the protein and mRNA levels of matrix metalloproteinase (MMP)-2 and MMP-9 in endometriotic cells. Moreover, extracellular signal-regulated kinase (ERK)1/2 was activated by PFE treatment, and an ERK1/2 inhibitor, PD98059, significantly inhibited PFE-inhibited cell migration in endometriotic cells. Furthermore, PFE significantly suppressed endometriotic lesion formation in a mouse model. These data suggest that Pueraria flower is a potential anti-endometriotic agent for the inhibition of endometriotic cell adhesion, migration, and MMP expression.

Evaluation of the Estrogenic Activity of Pueraria (Kudzu) Flower Extract and Its Major Isoflavones Using ER-Binding and Uterotrophic Bioassays

Pueraria flower extract (PFE) is a hot water extract of the Kudzu flower (Pueraria thomsonii). Tea made from dried Kudzu flower is widely used inChina, and PFE is utilized as a nutritional supplement inJapan. PFE contains unique isoflavones such as 6-hydroxygenistein 6,7-di-O-glucoside (6HGDG), tectorigenin 7-O-xylosylglucoside (TGXG), and tectoridin. 6HGDG is known to be metabolized into 6-hydroxygenistein, and TGXG and tectoridin are known to be metabolized into tectorigenin in the digestive tract. Isoflavones typically mimic the effects β-estradiol has on estrogen receptors (ERs) and may influence the female genital system in the case of excessive intake. As a result, the upper limit of safe daily consumption of soy isoflavones has been enforced inJapan. In the present study, ER-binding assays were performed using the EnBio estrogen receptor/cofactor assay system to compare the estrogenic activity of 6-hydroxygenistein and tectorigenin to that of the soy isoflavone genistein. In addition, uterotrophic bioassays were performed to investigate the estrogenic effects of PFE in vivo. The ER-binding assays revealed that the ER-binding affinities of 6-hydroxygenistein and tectorigenin were approximately 0.01 - 0.04 that of genistein. Soy isoflavone products also induced an increase in uterine wet and blotted weight at doses of 500 mg/kg and 1000 mg/kg, whereas PFE did not cause adverse estrogenic effects, even at a dose of 1000 mg/kg. Based on these results, PFE does not appear to contain compounds with strong estrogenic activity or cause adverse estrogenic effects in vivo. Importantly, the results of this study confirm the safety of PFE as a food supplement.

Simultaneous Determination of Isoflavones, Saponins and Flavones in Flos Puerariae by Ultra Performance Liquid Chromatography Coupled with Quadrupole Time-of-Flight Mass Spectrometry

An ultra performance liquid chromatography (UPLC) coupled with quadrupole time-of-flight mass spectrometry (QTOF/MS) method is established for the rapid analysis of isoflavones, saponins and flavones in 16 samples originated from the flowers of Pueraria lobata and P. thomsonii. A total of 25 isoflavones, 13 saponins and 3 flavones were identified by co-chromatography of sample extract with authentic standards and comparing the retention time, UV spectra, characteristic molecular ions and fragment ions with those of authentic standards, or tentatively identified by MS/MS determination along with Mass Fragment software. Moreover, the method was validated for the simultaneous quantification of 29 components. The samples from two Pueraria flowers significantly differed in the quality and quantity of isoflavones, saponins and flavones, which allows the possibility of showing their chemical distinctness, and may be useful in their standardization and quality control. Dataset obtained from UPLC-MS was processed with principal component analysis (PCA) and orthogonal partial least squared discriminant analysis (OPLS-DA) to holistically compare the difference between both Pueraria flowers.

Simultaneous analysis of isoflavones and saponins in Pueraria flowers using HPLC coupled to an evaporative light scattering detector and isolation of a new isoflavone diglucoside

The Pueraria flowers, Puerariae Flos [Puerariae Lobatae Flos (the flowers of P. lobata) and Puerariae Thomsonii Flos (the flowers of P. thomsonii)], have been used as crude drugs to counteract the overconsumption of alcohol in Japan and China. Both types of Puerariae Flos contain a large amount of isoflavones and saponins. Simultaneous analysis of the total saponin and isoflavone fraction within the flowers has proven difficult thus far; however, profile analysis of saponin and isoflavone levels was attempted in this study by using HPLC coupled to an evaporative light scattering detector (ELSD). A characteristic peak of kakkalide was common in the chromatograms of extracts originating from the flowers of P. lobata, though original habitats were different. Tiny peaks of saponins were also observed in chromatograms of all specimens derived from P. lobata. In the chromatograms of six out of eight extracts of Puerariae Thomsonii Flos originating from Guangdong, China, characteristic twin peaks corresponding to tectorigenin 7-O-xylosylglucoside and tectoridin were observed. The distinctive twin peaks were not found in the chromatograms of the extracts produced in Hunan and Sichuan. Although the amounts of total saponins and isoflavones obtained from Puerariae Lobatae Flos were almost the same, those of Puerariae Thomsonii Flos varied remarkably and were not related to habitat. A good yield of a new isoflavone glycoside was obtained from some specimens of Puerariae Thomsonii Flos; the structure was determined to be 6-hydroxygenistein 6,7-di-O-glucoside.

Inhibitory activity of isoflavones of Pueraria flowers on nitric oxide production from lipopolysaccharide-activated primary rat microglia

Microglial activation plays an important role in alcohol-induced neuroinflammation. In search for natural medicines that may be of therapeutic potential for alcoholism, two new natural isoflavone glycosides, 6-hydroxybiochanin A-6,7-di-O-β-d-glucopyranoside (1) and 6-hydroxygenistein-7-O-β-d-glucopyranoside (2), were isolated from the ethanolic extract of the flowers of Pueraria thomsonii Benth., together with the seven known isoflavones, genistein (3), tectorigenin (4), irisolidone (5), genistin (7), tectoridin (8), tectorigenin-7-O-β-d-xylosyl-(1 → 6)-β-d-glucopyranoside (9), and 6-hydroxygenistein-6,7-di-O-β-d-glucopyranoside (11). Moreover, gehuain (6) and kakkalide (10) were obtained from the flowers of Pueraria lobata (Willd.) Ohwi. The structures of the new compounds were elucidated by UV, IR, HR-MS, and 1D and 2D NMR spectroscopic methods. Compounds 3–5 substantially inhibited the lipopolysaccharide-induced nitric oxide release from primary cultured rat cortical microglia (IC50: 1.3–9.3 μM). The inhibitory effects of compounds 6, 8, 9, and 11 (IC50: 38–62 μM) were significant but weaker than the above aglycones. However, compounds 1, 2, 7, and 10 showed little inhibitory activity. With regard to the structure–activity relationships of the isoflavonoids for the inhibition of microglial activation, the glycosylation at the C-7 hydroxyl group reduces the inhibitory activity. The methoxylation of 4′-hydroxyl group of 7-glycosylated isoflavonoids reduces the inhibitory activity, while the methoxyl group at the 6-position enhances the activity. The results suggest that isoflavonoids of Pueraria flowers may be of therapeutic potential in alcoholism related to microglial activation.

Microbial transformation and bioactivation of isoflavones from Pueraria flowers by human intestinal bacterial strains

The flowers from Pueraria, which are called Puerariae Flos, have been used since ancient times for recovery from alcohol intoxication. We elucidated the microbial transformation of the main isoflavones (1, 1a and 2) by using 29 commercially available human intestinal bacterial strains together with the bioactivation of the hepatoprotective activity of their metabolites. Tectoridin (1a), which contains only one glucosyl moiety, was metabolized to its aglycone 1b by various bacterial strains. On the other hand, the metabolism of 1 and 2, which both have disaccharide groups, was limited to specific bacterial strains. The metabolites 1c and 2c obtained from the Peptostreptococcus productus strain were completely different from those produced by the other strains. These metabolites were identified as 6-hydroxygenistein and 6-hydroxybiochanin A, respectively. The glycosides 1, 1a and 2 did not show any hepatoprotective activity, whereas aglycones 1b and 2b showed moderate activity. Furthermore, the hepatoprotective activity of the demethylated metabolites 1c and 2c was extremely potent. Although not all people have P. productus in their gastrointestinal tract, the O-demethylated compounds might become one of the bioactivated metabolites when Puerariae Flos is administered orally.

Isolation of a new isoflavone from Chinese Pueraria flowers.

A new isoflavone, 6, 4'-dihydroxy-7-methoxy-isoflavone, was isolated from Chinese Pueraria flowers.