Isoflavone Content Research Articles

UV-B radiation enhances isoflavone accumulation and antioxidant capacity of soybean calluses.

Isoflavones are a class of flavonoids that belong to a large family of polyphenols and synthesized predominantly in legume, and they play important roles including acting as antioxidant, preventing osteoporosis, reducing the risk of atherosclerosis, and protecting against cardiovascular disease. This study focused on the accumulation and synthetic metabolism of isoflavone in soybean hypocotyl and cotyledon calluses under UV-B radiation. The results showed that UV-B radiation significantly up-regulated the gene expression of phenylalanine ammonia lyase (PAL), cinnamate-4-hydroxylase (C4H), 4-coumarate-CoA ligase (4CL), chalcone ketone synthase (CHS), chalcone isomerase (CHI), and isoflavone synthase (IFS), and enhanced their activity in soybean hypocotyl and cotyledon calluses. As a result, isoflavones content increased by 21.23 and 21.75% in soybean hypocotyl and cotyledon calluses, respectively. Among the isoflavones produced, malonyldaidzin was the dominant one in hypocotyl callus, while malonylglycitin and daidzein were the main isoflavones in cotyledon calluses. This study revealed that UV-B radiation induced isoflavone accumulation in soybean calluses, which could be an efficient strategy to improve the nutritional value of food and produce high levels of bioactive secondary metabolites.

Identification of QTNs, QEIs interactions and genes for isoflavones in soybean seeds

Isoflavones are important components of soybean seeds, and the contents affect the nutritional value of soybean products. To further reveal and improve the regulation mechanism of soybean isoflavones content, it is an effective way to construct a large enough germplasm combination and explore the genetic loci related to soybean isoflavone traits. In this study, 179 local soybean germplasms mainly from China were selected to analyze the phenotypic diversity and genetic basis of isoflavone content in soybean seeds. The genome-wide association studies (GWAS) using 3VmrMLM model combined the isoflavone phenotype with 23,131 single nucleotide polymorphisms (SNPs), we identified 97 genetic loci related to isoflavone traits in single environment and 20 genetic loci related to isoflavone traits in multiple environments, after that screened 6 potential genes related to total isoflavone content, daidzein, glycitein and genistein. Glyma.09G037300 and Glyma.18G111200 related to multiple traits of soybean isoflavones are highly expressed in soybean seeds. Haplotype analysis shows that Glyma.09G037300 and Glyma.18G111200 are higher expression in the high isoflavone populations than low isoflavone populations. Transient overexpression of Glyma.18G111200 increased the content of total isoflavones in hairy roots by 30–51%. These results revealed the genetic basis of soybean isoflavones, provided a series of predictable potential genes affecting the synthesis and accumulation of soybean isoflavones, and updated the research on soybean isoflavone related genes and genetic related loci. This provide a valuable basis for the functional study of soybean isoflavones.

Solid-State Fermentation of Soybean Meal with Edible Mushroom Mycelium to Improve Its Nutritional, Antioxidant Capacities and Physicochemical Properties

Soybean meal is a class of by-products obtained from the processing of soybean products. Despite its high nutritional value, the presence of glycoside isoflavones limits human use of soybean meal. This study evaluated the effect of solid-state fermentation (SSF) with different edible mushroom mycelia (Pleurotus ostreatus, Hericium erinaceus, and Flammulina velutipes) on the proximate composition, antioxidant properties, and physicochemical properties of fermented soybean meal powder (SP). The results revealed that fermented SP had a higher nutritional value when compared to SP. P. ostreatus was the most pronounced among the three species. Crude protein content was found to have increased by 9.49%, while the concentration of glutamate and aspartic acid increased by 23.39% and 23.16%, respectively. SSF process significantly increased the total polyphenol content (TPC) and aglycone isoflavone content by 235.9% and 324.12%, respectively, resulting in increased antioxidant activity (evaluated by the DPPH, •OH, ABTS+ assays). Microstructural changes in fermented SP and nutrient degradation and utilization were observed. Thus, fermented SP can be used as a raw material with enhanced nutritional properties to develop new functional foods, such as plant-based foods represented by plant meat. It provides a promising approach for increasing the added value of soybean meal.

Developmental dynamic transcriptome and systematic analysis reveal the major genes underlying isoflavone accumulation in soybean.

Soy isoflavone, a class of polyphenolic compounds exclusively occurred in legumes, is an important bioactive compound for both plants and human beings. The outline of isoflavones biosynthesis pathway has been drawn up basically in the previous research. However, research on the subject has been mostly restricted to investigate the static regulation of isoflavone content in soybean, rather than characterize its dynamic variation and modulation network in developing seeds. In this study, by using eight recombinant inbred lines (RIL), the contents of six isoflavone components in the different stages of developing soybean seeds were determined to characterize the dynamic variation of isoflavones, and the isoflavones accumulation pattern at physiological level was investigated. Meanwhile, we integrated and analyzed the whole genome expression profile of four lines and 42 meta-transcriptome data, based on the multiple algorithms. This study: 1) obtained 4 molecular modules strongly correlated with isoflavone accumulation; 2) identified 28 novel major genes that could affect the accumulation of isoflavones in developing seeds free from the limitation of environments; 3) discussed the dynamic molecular patterns regulating isoflavones accumulation in developing seed; 4) expanded the isoflavone biosynthesis pathway. The results not only promote the understandings on the biosynthesis and regulation of isoflavones at physiological and molecular level, but also facilitate to breed elite soybean cultivars with high isoflavone contents.

Curcumin treatment enhances bioactive metabolite accumulation and reduces enzymatic browning in soybean sprouts during storage

Curcumin is a natural polyphenol that is widely used in food and medicine. Here, we investigated the effects of curcumin on the antioxidant accumulation and enzymatic browning of soybean sprouts after storage at 4 °C for 2 weeks. Curcumin drastically reduced the water loss, browning index, and peroxide accumulation, increased the activities of superoxide dismutase, catalase, and peroxidase, decreased the activities of phenylalanine ammonia-lyase and polyphenol oxidase, elevated the contents of ascorbic acid, reduced glutathione, nonprotein thiol, phenolics and isoflavones, and enhanced the total antioxidant capacity of soybean sprouts during storage. These curcumin-induced changes were partly but dramatically attenuated by inhibition of NADPH oxidase (NOX). Curcumin induced NOX activity and H2O2 burst in soybean sprouts during the first 24 h after treatment. The curcumin-induced antioxidants and -inhibited enzymatic browning are closely associated with NOX-dependent H2O2 signaling. The findings provide a new method for improving soybean sprout quality during storage.

Identification of hub genes regulating isoflavone accumulation in soybean seeds via GWAS and WGCNA approaches.

Isoflavones are the secondary metabolites synthesized by the phenylpropanoid biosynthesis pathway in soybean that benefits human and plant health. In this study, we have profiled seed isoflavone content by HPLC in 1551 soybean accessions grown in Beijing and Hainan for two consecutive years (2017 and 2018) and in Anhui for one year (2017). A broad range of phenotypic variations was observed for individual and total isoflavone (TIF) content. The TIF content ranged from 677.25 to 5823.29 µg g-1 in the soybean natural population. Using a genome-wide association study (GWAS) based on 6,149,599 single nucleotide polymorphisms (SNPs), we identified 11,704 SNPs significantly associated with isoflavone contents; 75% of them were located within previously reported QTL regions for isoflavone. Two significant regions on chromosomes 5 and 11 were associated with TIF and malonylglycitin across more than 3 environments. Furthermore, the WGCNA identified eight key modules: black, blue, brown, green, magenta, pink, purple, and turquoise. Of the eight co-expressed modules, brown (r = 0.68***), magenta (r = 0.64***), and green (r = 0.51**) showed a significant positive association with TIF, as well as with individual isoflavone contents. By combining the gene significance, functional annotation, and enrichment analysis information, four hub genes Glyma.11G108100, Glyma.11G107100, Glyma.11G106900, and Glyma.11G109100 encoding, basic-leucine zipper (bZIP) transcription factor, MYB4 transcription factor, early responsive to dehydration, and PLATZ transcription factor respectively were identified in brown and green modules. The allelic variation in Glyma.11G108100 significantly influenced individual and TIF accumulation. The present study demonstrated that the GWAS approach, combined with WGCNA, could efficiently identify isoflavone candidate genes in the natural soybean population.

A Soy Protein Isolate Rich in Genistein and Daidzein and Its Effects on Plasma Isoflavone Concentrations, Platelet Aggregation, Blood Lipids and Fatty Acid Composition of Plasma Phospholipid in Normal Men

The effects of consuming a soy protein isolate beverage powder (60 g/d for 28 d) vs. a casein supplement was evaluated in 20 male subjects who were randomly allocated into the two groups. A dramatic rise in plasma isoflavone concentrations was observed after supplementation in the soy protein group, the levels reaching 907 ± 245 nmol/L for genistein (a 110-fold increase) and 498 ± 102 nmol/L for daidzein (a 150-fold increase) as measured by isotope dilution gas chromatography - mass spectrometry. These concentrations are higher than previously reported for the plasma of Japanese subjects consuming a traditional diet (276 nmol/L and 107 nmol/L, respectively). No significant differences in collagen- or 9,11-dideoxy-11α, 9α-epoxymethanoprostaglandin F2α (U46619)-induced platelet aggregation were observed in platelet-rich plasma from the two groups; the increase in plasma isoflavonoids from soy protein supplementation is not sufficient to significantly inhibit platelet aggregation ex vivo. Similarly, plasma total and HDL-cholesterol were not affected by protein supplementation, possibly because the men were normo-cholesterolemic at entry. Analysis of plasma phospholipid polyunsaturated fatty acid composition showed no differences between soy protein and casein supplementation. Previous investigations reported a significant alteration in fatty acid status in animals fed soy protein relative to those fed casein. The present studies indicate that although soy protein supplementation to a typical Western diet can increase plasma concentrations of isoflavones, this may not necessarily be sufficient to counter heart disease risk factors such as high plasma cholesterol and platelet aggregation.

Dairy calves are exposed to isoflavones during the developmentally most sensitive period of their life

Isoflavones represent a class of phytoestrogens present in plants. In dairy cows, dietary isoflavones have been shown to negatively affect reproductive performance. To the best of our knowledge, no studies have yet been conducted to determine if calves are pre- or neonatally confronted with isoflavones and their metabolites. In the present study, we hypothesize that isoflavones are passed on from the dam to the offspring in utero. Twenty-three pregnant Holstein Friesian dams and their calves, originating from three commercial dairy farms in Belgium, were included. Heparin blood samples were collected during the first, second, and third trimester of gestation from all pregnant dams. Heparin blood and hair samples were obtained from the offspring within 24 h after parturition. Colostrum samples were collected from a subset of eight dams to determine the concentration of isoflavones and their metabolites. During the first and second trimester of gestation, the dams were fed either a youngstock (nulliparous dams) or a lactation (multiparous dams) diet. During the third trimester, both groups received a similar dry cow diet. Genistein and daidzein levels were unaffected by diet type, while their metabolite [equol, dihydrodaidzein (DHD), and o-desmethylangolensin (ODMA)] concentrations were significantly higher in the lactation group. Furthermore, metabolite concentrations decreased significantly during gestation. Isoflavones and their metabolites were detected in all colostrum samples. No correlation could be found between levels in colostrum and blood of pregnant dams or calves. Peripheral levels of isoflavones and their metabolites were significantly lower in newborn calves in comparison to their dams. Genistein and daidzein concentrations were found to be significantly higher in the calves' hair versus blood samples, suggesting prenatal exposure to isoflavones for an extended period of time. In contrast, no isoflavone metabolites were detected in the calves’ hair samples. This is the first study to demonstrate that dairy calves are exposed to isoflavones during the developmentally most sensitive period of their lives. Results obtained pave the way for more extensive research to examine which effects isoflavones might have on developing organ systems like the reproductive system.

The Role of Isoflavones in the Prevention of Breast Cancer and Prostate Cancer

This narrative review summarizes epidemiological studies on breast cancer and prostate cancer with an overview of their global incidence distribution to investigate the relationship between these diseases and diet. The biological properties, mechanisms of action, and available data supporting the potential role of isoflavones in the prevention of breast cancer and prostate cancer are discussed. Studies evaluating the effects of isoflavones in tissue cultures of normal and malignant breast and prostate cells, as well as the current body of research regarding the effects of isoflavones attained through multiple modifications of cellular molecular signaling pathways and control of oxidative stress, are summarized. Furthermore, this review compiles literature sources reporting on the following: (1) levels of estrogen in breast and prostate tissue; (2) levels of isoflavones in the normal and malignant tissue of these organs in European and Asian populations; (3) average concentrations of isoflavones in the secretion of these organs (milk and semen). Finally, particular emphasis is placed on studies investigating the effect of isoflavones on tissues via estrogen receptors (ER).

Apoplast-Localized β-Glucosidase Elevates Isoflavone Accumulation in the Soybean Rhizosphere.

Plant specialized metabolites (PSMs) are often stored as glycosides within cells and released from the roots with some chemical modifications. While isoflavones are known to function as symbiotic signals with rhizobia and to modulate the soybean rhizosphere microbiome, the underlying mechanisms of root-to-soil delivery are poorly understood. In addition to transporter-mediated secretion, the hydrolysis of isoflavone glycosides in the apoplast by an isoflavone conjugate-hydrolyzing β-glucosidase (ICHG) has been proposed but not yet verified. To clarify the role of ICHG in isoflavone supply to the rhizosphere, we have isolated two independent mutants defective in ICHG activity from a soybean high-density mutant library. In the root apoplastic fraction of ichg mutants, the isoflavone glycoside contents were significantly increased, while isoflavone aglycone contents were decreased, indicating that ICHG hydrolyzes isoflavone glycosides into aglycones in the root apoplast. When grown in a field, the lack of ICHG activity considerably reduced isoflavone aglycone contents in roots and the rhizosphere soil, although the transcriptomes showed no distinct differences between the ichg mutants and wild-types (WTs). Despite the change in isoflavone contents and composition of the root and rhizosphere of the mutants, root and rhizosphere bacterial communities were not distinctive from those of the WTs. Root bacterial communities and nodulation capacities of the ichg mutants did not differ from the WTs under nitrogen-deficient conditions either. Taken together, these results indicate that ICHG elevates the accumulation of isoflavones in the soybean rhizosphere but is not essential for isoflavone-mediated plant-microbe interactions.

Sugar and Isoflavone Contents of Traditional Korean Soybean Fermented Foods

Sugar and Isoflavone Contents of Traditional Korean Soybean Fermented Foods

Feeding Soy Protein Concentrates with Low and High Isoflavones Alters 9 and 18 Weeks Serum Isoflavones and Inflammatory Protein Levels in Lean and Obese Zucker Rats

Soy's anti-inflammatory properties contribute to the health benefits of soy foods. This study was designed to investigate the bioavailability of soy isoflavones and whether the isoflavone content of soy protein concentrate diet would affect serum inflammatory proteins in an obese (fa/fa) Zucker rat model. Six-week-old male lean (L) and obese (O) Zucker rats were fed a casein control diet (C), soy protein concentrate with low isoflavones (SPC-LIF), or soy protein concentrate with high isoflavones (SPC-HIF) (7 rats/dietary group) before being killed at 9 and 18 weeks. Serum samples were analyzed for isoflavones and inflammatory proteins. At both time points, serum total (aglycone + conjugates) genistein, daidzein, and equol concentrations were significantly higher in L-SPC-HIF and O-SPC-HIF groups compared with L-SPC-LIF and O-SPC-LIF groups, respectively, and were not detectable in either L-C or O-C groups. At week 9, serum C-reactive protein (CRP) concentration was significantly lower in O-SPC-HIF group compared with O-C and O-SPC-LIF group, whereas proteins tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) levels did not differ between any groups. At week 18, serum CRP levels in both O-SPC-HIF and O-SPC-LIF groups were significantly lower compared with the O-C group. TNF-α level was higher in the O-SPC-LIF group compared with both O-C and O-SPC-HIF groups, whereas IL-6 levels were not different between any groups. Taken together, feeding Zucker rats SPC-LIF and SPC-HIF diets led to different serum isoflavone concentrations in both L and O Zucker rats and altered CRP and TNF-α levels in obese Zucker rats compared with controls.

Formation and physical characterization of soy protein-isoflavone dispersions and emulsions

Proteins stabilize emulsions by adsorbing at the interface to prevent the natural tendency of droplet coalescence. Polyphenols (plant-derived secondary metabolites) are capable of complexing with proteins through structural interactions. Certain polyphenols have shown influence on interfacial properties of proteins, yet isoflavones specifically have not been widely investigated. Thus, the objective of this research was to study the effect of isoflavones on protein-stabilized oil-in-water emulsions. Soy protein fractions, assessed via SDS-PAGE and bicinchoninic acid assay, contained primarily β-conglycinin (7S) and glycinin (11S). Notable isoflavones identified from HPLC analysis were daidzin, genistin, and glycitin. Physical characteristics (size, zeta potential, polydispersity index, and wettability) of soy protein isolate-isoflavone (SPI–I) dispersions and emulsion droplets were measured with a Zetasizer Nano ZS and goniometer. Isoflavone addition significantly increased the contact angle of sessile drops towards neutral wettability. Heating appeared to significantly improve colloidal stability and emulsion droplets formed with heated SPI-I dispersions sustained size (∼200–245 nm) and zeta potential (∼-30-35 mV) over 7 days, with higher concentrations of isoflavones being generally correlated with smaller emulsion droplets. Collectively, these findings indicate that isoflavone addition improved emulsion stability compared to the control without isoflavones and that they can contribute to colloidal stability of food products.

Effect of exogenous melatonin on the isoflavone content and antioxidant properties of soybean sprouts

Sprouting can increase the nutritional quality of seeds, such as soybeans. The current study aimed to evaluate the influence of exogenous melatonin (MLT; 100 and 300 μmol/L) on the isoflavone content and antioxidant properties of two soybean cultivars’ germination process (5, 6, and 7 days). MLT treatments significantly increased the sprout length and germination rate by 53% and 12%, respectively, when compared to water-treated soybean sprouts. Further, seven main isoflavones were quantified, with the highest total isoflavone content (5.101 g/kg) found on day 5 when using 100 μmol/L MLT. Additionally, when applying the same concentration, the highest levels of SOD and CAT were found, with values of 10.05 and 15.10 μkat/g, respectively, therefore resulting in a decrease in malondialdehyde (MDA), hydrogen peroxide (H2O2), and nitric oxide (NO) contents. MLT enhanced the expression levels of several genes related to antioxidant properties, seed germination, and root length. Overall, MLT is a suitable inducer for promoting soybean germination and enhancing the isoflavone content and antioxidant properties of soybean sprouts.

Therapeutic and Anti-Thrombotic Properties of Some Naturally Fermented Soybean Foods of the Eastern Himalayas

Naturally fermented soybean foods have anti-thrombotic properties due to the presence of microbial fibrinolytic enzymes. However, fibrinolytic enzyme-producing bacteria from naturally fermented soybean foods of the Eastern Himalayas viz. kinema, grep-chhurpi, peha, peron namsing, peruñyaan and bemerthu have not been screened yet. Therefore, this study aims to screen the fibrinolytic enzyme-producing bacteria from these naturally fermented soybean foods and also to assess their therapeutic properties such as antioxidant, anti-inflammatory, flavones, isoflavones, anti-obesity and anti-diabetic properties of samples. A total of 877 bacteria were isolated, out of which Bacillus subtilis (ten strains), B. velezensis (three strains), B. inaquosorum (two strains) and B. halotolerans (one strain) showed fibrinolytic enzyme activity ranging from 775.70 U/mL to 1230.61 U/mL, with a blood clot-degrading property of more than 50%. A remarkable DPPH radical scavenging property (>50%), flavone (278.98 ± 7.06 µg QE/g) and isoflavone (394.13 ± 11.68 µg GEN/g) contents were observed. The Himalayan fermented soybean foods have shown anti-thrombotic, antioxidant, anti-inflammatory, anti-diabetic and anti-obesity properties indicating their therapeutic values.

DIFFERENCES IN ESTROGEN LEVELS BEFORE AND AFTER GIVING CALLANGGI TEA TO WISTAR STRAINING WHITE FEMALE RATS (RATTUS NORVEGICUS) IN MEDROXYPROGESTERONE ACETATE (DMPA) INDUCTION

Data from the 2017 Indonesian Demographic and Health Survey (IDHS) show that hormonal injection contraception has been the most common choice taken by women in more than 90 countries worldwide since 1967. Hormonal contraception uses essential ingredients from synthetic hormones used to regulate pregnancy. The 3-month injection KB (Depo-medroxprogestin acetate/DMPA) has the highest rating, 46.84%. DMPA thickens the cervical mucus, interfering with the ovulation process. The affects couples of childbearing age to get offspring quickly, causing stress where women often experience anxiety, depression, and prolonged fatigue that affect hormones and female reproductive organs. Midwifery care has been carried out by combining conventional and complementary midwifery services, which have become an essential part of midwifery practice. Decree of the Minister of Health Number 1109/Menkes/Per/IX/2007 concerning Alternative Complementary Medicine. Complementary is complementary, perfecting. Complementary therapy is carried out to complement conventional medical treatment and is rational, and does not conflict with health values ​​and laws in Indonesia. There are several methods of accelerating fertility recovery, one of which is using medicinal plants as an alternative, namely clover. The community widely uses clover for daily consumption. In this study, the method used as clover in a tea preparation is to be induced orally in female Wistar rats. Clover belongs to the water spike group, which contains isoflavones, antioxidants, and anti-inflammatories. The content of isoflavones in clover leaves can balance female hormones. The results of this research are beneficial for the development of science and technology, especially complementary therapy regarding the potential of clover as a natural ingredient that helps restore fertility

The nutritional composition of the vegetable soybean (maodou) and its potential in combatting malnutrition.

Global malnutrition continues to be a canker owing to poor eating habits and over-reliance on the major staple crops. Vegetable soybean (maodou) is gaining popularity globally as an affordable snack and vegetable. In this study, we profiled the nutritional composition of 12 soybean cultivars at the vegetable (R6-R7) and mature (R8) stages. We also conducted an RNA-seq analysis during seed development, focusing on key biosynthesis enzymes for quality traits. The results showed that 100 g of maodou contained 66.54% moisture, 13.49% protein, 7.81% fatty acids, 2.47% soluble sugar, abundant content of minerals, and micronutrients, including folate (462.27 μg FW) and carotenoids (3,935.41 μg FW). Also, the isoflavone content of maodou ranged between 129.26 and 2,359.35 μg/g FW. With regard to the recommended daily allowance, 100 g fresh weight of maodou can contribute 26.98, 115.57, and 11.60% of protein, folate, and zinc, respectively, and significant proportions of other nutrients including linoleic acid (21.16%), linolenic acid (42.96%), zinc (11.60%), and iron (18.01%). On a dry weight basis, maodou has two to six folds higher contents of folate, tocopherol, and carotenoid than the mature soybean. Furthermore, RNA-seq analysis revealed that key biosynthesis enzymes of quality traits are differentially expressed during seed development and may contribute to variations in the content of quality traits at the vegetable and mature stages. Correlation analysis of quality traits at both stages revealed that protein only correlated positively with zinc at the vegetable stage but negatively correlated with total tocopherol and total fatty acid at the mature stage. Complex associations among folates, soluble sugar, and isoflavones were also identified. This study provides insight into the nutritional contents of vegetable soybean and demonstrates that maodou is essential for meeting the nutritional requirements of most countries.

Identification of genes for seed isoflavones based on bulk segregant analysis sequencing in soybean natural population.

We identified four hub genes for isoflavone biosynthesis based on BSA-seq and WGCNA methods and validated that GmIE3-1 positively contribute to isoflavone accumulation in soybean. Soybean isoflavones are secondary metabolites of great interest owing to their beneficial impact on human health. Herein, we profiled the seed isoflavone content by HPLC in 1551 soybean accessions grown in two locations for two years and constructed two extreme pools with high (4065.1µgg-1) and low (1427.23µgg-1) isoflavone contents to identify candidate genes involved in isoflavone biosynthesis pathways using bulk segregant analysis sequencing (BSA-seq) approach. The results showed that the average sequencing depths were 50.3× and 65.7× in high and low pools, respectively. A total of 23,626 polymorphic SNPs and 5299 InDels were detected between both pools and 1492 genes with different variations were identified. Based on differential genes in BSA-seq and weighted gene co-expression network analysis (WGCNA), four hub genes, Glyma.06G290400 (designated as GmIE3-1), Glyma.01G239200, Glyma.01G241500, Glyma.13G256100 were identified, encoding E3 ubiquitin-protein ligase, arm repeat protein interacting with ABF2, zinc metallopeptidase EGY3, and dynamin-related protein 3A, respectively. The allelic variation in GmIE3-1 showed a significant influence on isoflavone accumulation. The virus-induced gene silencing (VIGS) and RNAi hairy root transformation of GmIE3-1 revealed partial suppression of this gene could cause a significant decrease (P < 0.0001) of total isoflavone content, suggesting GmIE3-1 is a positive regulator for isoflavones. The present study demonstrated that the BSA-seq approach combined with WGCNA, VIGS and hairy root transformation can efficiently identify isoflavone candidate genes in soybean natural population.

Leaf formononetin content of Trifolium subterraneum increases in response to waterlogging but its proportion of total isoflavones is little changed.

The isoflavone formononetin (F) impacts livestock fertility and cultivars of the pasture legume Trifolium subterraneum L. (subclover) have been selected for F levels ≤0.2% of leaf dry weight. However, the impact of waterlogging (WL) on isoflavones is little studied. We investigated the response of isoflavones, biochanin A (BA), genistein (G) and F, to WL for: (1) Yarloop (high F) and eight low F cultivars each from subspecies subterraneum , brachycalycinum and yanninicum (Experiment 1); and (2) four cultivars and 12 ecotypes of ssp. yanninicum (Experiment 2). WL impacted F: estimated means increased from 0.19% (control) to 0.31% (WL) in Experiment 1 and from 0.61% to 0.97% in Experiment 2. Isoflavones under WL were highly heritable, particularly F (H 2 =95%). The proportions of BA, G and F were little changed by WL, with strong positive correlations between free-drained and waterlogged treatments. Isoflavone contents were not related to WL tolerance, as assessed by shoot relative growth rate. In conclusion, isoflavones varied among genotypes and increased with WL, but the proportion of individual isoflavones in each genotype was stable. High F under WL was unrelated with genotype tolerance to WL. Instead, it was a consequence of inherently high F for that particular genotype.

Avaliação nutricional e aceitação pelo consumidor de extrato de soja de cultivares especiais e convencionais

Abstract The soymilk is a ready-to-eat, nutritious and naturally cholesterol-free product. Several soybean specialty cultivars were developed in Brazil in order to increase the human consumption of soybean products. The aim of this work was to evaluate the nutritional composition and consumer acceptance of soymilk from three soybean cultivars with special features such as high-protein and isoflavone contents, mild flavor and lipoxygenase-free compared to three conventional ones. The soymilk was obtained after blanching with a bicarbonate solution, grinding, centrifugation and pasteurization. The physicochemical and nutritional evaluation data were analyzed using Analysis of Variance (ANOVA) and Tukey’s test to check differences among means, and the consumer data through cluster analysis and internal preference mapping. The lipoxygenases were inactivated after thermal processing. There were significant differences among soybean cultivars and soymilks related to the protein, isoflavones, oil, and sugar contents and soymilk yield (p &lt; 0.05). The BRS 133 and BRS 284 cultivars and soymilks presented the highest total isoflavone content (p &lt; 0.05). Regarding the overall consumer acceptance, there were significant differences among cultivars (p &lt; 0.05) with means ranging from 5.9 to 6.7 and the lower score was obtained by BRS 267. However, the cluster analysis identified three consumer segments according to preference similarity. The cultivars BRS 284 and BRS 267 reached the highest mean among the consumers of segment 1 (6.8 and 6.7 respectively). The consumers of segment 2 preferred the cultivar without lipoxygenases, BRS 213 (mean of 7.5) while segment 3 preferred the BRS 133 (mean of 7.4). The process of blanching of soybean with bicarbonate solution, grinding with boiling water and pasteurization mitigated the differences between conventional and specialty cultivars and the six cultivars evaluated were suitable for soymilk production.