Simple preparation and analysis of a phytoestrogen-rich extract of Pueraria candollei var. mirifica and its in vitro estrogenic activity

Different LED Colors and Pre-Drying Treatments Enhance Isoflavonoid Production and Estrogenic Activity in Pueraria candollei Callus Cultures

Callus cultures of Pueraria candollei are effective phytoestrogen sources and are a feasible commercial alternative to agricultural farming and traditional cultivation due to their rapid growth and sufficient production of bioactive compounds. How different light wavelengths impact secondary metabolite accumulation in callus cultures of P. candollei remains unclear. In this study, we focused on enhancing phytoestrogen levels in P. candollei callus extracts treated under different light conditions and pre-drying methods. Metabolite production, and estrogenic and anti-inflammatory activity of callus extracts were investigated using MCF-7 and RAW 264.7 cells, respectively. Callus cultured under white LED produced the highest growth index on Day 28 and stimulated significant upregulation of HID, CYP81E, and PT-1 by 1.6-, 4.8-, and 56-fold, respectively. Callus treated with red LED increased daidzin, genistin, and deoxymiroestrol levels (0.613 ± 0.042 mg g-1, 0.549 ± 0.033 mg g-1, and 1.46 ± 0.24 μg g-1 dry weight, respectively). The total isoflavonoid content in the callus extract increased by 3- and 2-fold under red and white LED lights, respectively. The extract of callus-treated white LED at Day 28 significantly suppressed nitric oxide production from 100% to 54.8% ± 2.8%. The strongest estrogenic activity was obtained in callus extract grown under red LED with a pre-drying step, which was attributed to higher levels of deoxymiroestrol. The red and white LED light stimulated the formation of phytoestrogens in callus cultures of P. candollei. The pre-drying treatment enhanced aglycone secondary metabolites and pharmacological activity of callus. Our findings indicate that the therapeutic potential of P. candollei can be enhanced by facilitating controlled and efficient production of its bioactive compounds.

Exploring kudzu: Extraction, quantification, and health impacts of bioactive compounds

Kudzu (Pueraria species) is a perennial plant within the Fabaceae family, native to China, Japan, and India. It is known for its therapeutic properties, mainly due to its high content of isoflavones, including puerarin, daidzein, daidzin, genistein, and genistin. These isoflavones are found throughout the plant and are important in developing pharmaceutical drugs. This review comprehensively analyzes naturally occurring isoflavones in Kudzu, focusing on advanced and green techniques for their extraction, purification, and identification. Additionally, it highlights their health benefits and the growing demand in the global food and pharmaceutical industries. Due to their superior efficiency, scalability, and cost-effectiveness, contemporary eco-friendly extraction methods like ultrasound, microwave, enzyme-assisted, and supercritical fluid extraction are gaining prominence in this endeavor. They are crucial in optimizing the extraction process, driving innovation within industries, and harnessing natural sources, ultimately boosting global economies. Scientific studies confirm that Kudzu isoflavones have various anti-diabetic, neuroprotective, anti-cancer, antioxidant, alcohol detoxification, and cardiovascular protective effects. This review encourages further exploration of Kudzu isoflavones as a nutritional food source. It also highlights advancements in extraction methods within pharmaceuticals and natural products, underscoring the superiority of modern techniques over conventional ones. Additionally, critical analysis of the trends, limitations, and scope of Kudzu-extracted isoflavones for novel food applications can further advance scientific understanding.

Estrogenic Activity of Derris scandens Stem Extract and its Major Compounds Using MCF-7 Cell Proliferation Assay and Estrogen-Related Gene Expression

Derris scandens, which contains isoflavones and prenylated derivatives, has analgesic and anti-inflammatory properties and is an ingredient in traditional Thai medicine for perimenopause and menopause. However, the estrogenic activity of D. scandens has not yet been explored. Therefore, this study aimed to examine the estrogenic activity of the stem extract of D. scandens and its isoflavone derivatives. In this study, we conducted a proliferation assay in MCF-7 cells, and used quantitative reverse transcription polymerase chain reaction to assess gene expression. We found that the relative cell proliferation of the compounds (1 µM) was ranked in the following order as compared to 0.1 nM 17β-estradiol (100%): genistein (97.84%) > derrisisoflavone A (83.17%) > genistein-7-O-[α-rhamnopyranosyl-(1 → 6)-glucopyranoside] (69.55%) > 6,8-diprenylgenistein (51.91%) > lupalbigenin (18.72%). Furthermore, cotreatment with 1 µM lupalbigenin and 0.1 nM 17β-estradiol was performed, which decreased cell proliferation to 80.38%. In vitro results suggest that lupalbigenin has an estrogen-antagonistic effect. At a dose of 1 µM, genistein had the strongest efficacy in increasing the expression of human estrogen receptor β by 4.0-fold compared to the control. Furthermore, genistein-7-O-[α-rhamnopyranosyl-(1 → 6)]-β-glucopyranoside augmented the gene expression of human estrogen receptor α and human estrogen receptor β by 1.5- and 3.4-fold, respectively. Prenylated derivatives of genistein (derrisisoflavone A, 6,8-diprenylgenistein, and lupalbigenin) significantly suppressed the gene expression of the human androgen receptor. The administration of the crude extract at 10 µg/mL significantly suppressed human androgen receptor (0.6-fold) and transmembrane protease serine 2 (0.1-fold) expression but did not significantly affect human estrogen receptor α and human estrogen receptor β gene expression. This herbal medicine may be safe for estrogen-exposed breast cancer patients.

Immunoaffinity separation of miroestrol and deoxymiroestrol from Pueraria candollei var. mirifica (Airy Shaw & Suvat.) Niyomdham using fragment antigen-binding antibody produced via Escherichia coli

INTRODUCTION

Miroestrol and deoxymiroestrol are potent phytoestrogens and are oestrogen markers of Pueraria candollei var. mirifica. However, purifying these compounds is difficult because they only exist in trace amounts.

OBJECTIVES

Active fragment antigen-binding (Fab) antibodies were produced via Escherichia coli SHuffle® T7 and used to selectively separate these compounds.

MATERIALS AND METHODS

Two immunoaffinity separation approaches were developed, namely the immunoaffinity column (IAC) and a cell-based method. Group-specific Fab antibodies against miroestrol and deoxymiroestrol (anti-MD Fab) were used as biological binding reagents for selective separation.

RESULTS

The Fab-based IAC effectively separated miroestrol and deoxymiroestrol (0.65 and 2.24 μg per 2 mL of resin, respectively) from P. mirifica root extract. When P. mirifica extract was added to E. coli cultures during Fab expression via a cell-based method, the target compound accumulated in intracellular compartments and, thus, were separated from E. coli cells after the removal of other compounds. A yield of 1.07 μg of miroestrol per gram of cell pellet weight was obtained. Miroestrol and deoxymiroestrol were successfully purified from P. mirifica extract using anti-MD Fab via the IAC and an intracellular cell-based method.

CONCLUSION

The proposed methods can simplify the miroestrol and deoxymiroestrol extraction process and provide a basis for applications utilising recombinant antibodies to separate target compounds.

Transformation of Pueraria candollei var. mirifica phytoestrogens using immobilized and free β-glucosidase, a technique for enhancing estrogenic activity

Pueraria candollei var. mirifica (PM) has a significant beneficial effect on postmenopausal symptoms associated with estrogen deficiency. However, the estrogenic activity and intestinal absorption of isoflavonoid glycosides derived from PM, such as daidzin and genistin, are significantly lower than those of their aglycones. To enhance the estrogenic activity of the PM extract, we developed β-glucosidase and its immobilized form to increase the PM aglycone content (daidzein and genistein). The enzyme immobilization was done by alginate beads, and the resulting β-glucosidase alginate beads have a diameter of about 0.20 cm. Response surface methodology (RSM) was used to optimize certain parameters, such as the pH, temperature, and ethanol concentration. The optimal conditions of β-glucosidase for daidzein and genistein production were pH of 4.8–4.9, a temperature in the range 46.3–49.1 °C, and ethanol concentration of 10.0–11.0%. The ANOVA results indicated that the design experiment involving free and immobilized β-glucosidase was the best fit by quadratic models, which had adjusted R² values between 0.8625 and 0.9318. Immobilized β-glucosidase can be reused up to nine times and maintained efficacy of greater than 90%. Treatment of the PM extract with β-glucosidase increased the estrogenic activity of the PM extract by 8.71- to 23.2-fold compared to that of the untreated extract. Thus, β-glucosidase has a high potential for enhancing the estrogenic activity of PM constituents, and it can be applied on an industrial scale to increase the utility of these natural products.

Transformation of Pueraria candollei var. mirifica phytoestrogens by β-glucosidase increases estrogenic activity.