Isoflavone Content In Soybean Seeds Research Articles

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.

Genome wide association study to detect genetic regions related to isoflavone content in a mutant soybean population derived from radiation breeding.

Isoflavones are major secondary metabolites that are exclusively produced by legumes, including soybean. Soy isoflavones play important roles in human health as well as in the plant defense system. The isoflavone content is influenced by minor-effect quantitative trait loci, which interact with polygenetic and environmental factors. It has been difficult to clarify the regulation of isoflavone biosynthesis because of its complex heritability and the influence of external factors. Here, using a genotype-by-sequencing-based genome-wide association mapping study, 189 mutant soybean genotypes (the mutant diversity pool, MDP) were genotyped on the basis of 25,646 high-quality single nucleotide polymorphisms (SNPs) with minor allele frequency of >0.01 except for missing data. All the accessions were phenotyped by determining the contents of 12 isoflavones in the soybean seeds in two consecutive years (2020 and 2021). Then, quantitative trait nucleotides (QTNs) related to isoflavone contents were identified and validated using multi-locus GWAS models. A total of 112 and 46 QTNs related to isoflavone contents were detected by multiple MLM-based models in 2020 and 2021, respectively. Of these, 12 and 5 QTNs were related to more than two types of isoflavones in 2020 and 2021, respectively. Forty-four QTNs were detected within the 441-Kb physical interval surrounding Gm05:38940662. Of them, four QTNs (Gm05:38936166, Gm05:38936167, Gm05:38940662, and Gm05:38940717) were located at Glyma.05g206900 and Glyma.05g207000, which encode glutathione S-transferase THETA 1 (GmGSTT1), as determined from previous quantitative trait loci annotations and the literature. We detected substantial differences in the transcript levels of GmGSTT1 and two other core genes (IFS1 and IFS2) in the isoflavone biosynthetic pathway between the original cultivar and its mutant. The results of this study provide new information about the factors affecting isoflavone contents in soybean seeds and will be useful for breeding soybean lines with high and stable concentrations of isoflavones.

Silicon-mediated accumulation of oil and antioxidant in Soybean

The purpose of this study was to examine the effects of silica application on the protein, oil, fatty acid, phenol and isoflavone content in soybean seeds that experience water deficiency stress. This study used a factorial completely randomized design. The first factor was the watering interval (3, 6 and 9 day intervals). The second factor was the dosage of silica application (0; 31.25 and 62.50 SiO2/polybag or equivalent doses of 0, 125 and 250 kg SiO2/ha). This study concluded that the higher and longer duration of drought stress was reflected in the longer watering interval caused a decreased the number of filled pods, number and yield of seeds, and oil content, but increased content of protein, total of phenolic and isoflavan of soybean seeds. Application of silica under drought stress conditions reduced the reduction in the number of filled pods, seed quantity and yield, and oil content compared to without silica application. The content of oil, total of phenolic and isoflavones of soybean seeds can be inducted through the application of silica. The application of silica improves the quality of soybeans as a functional food.

Identification of a candidate gene associated with isoflavone content in soybean seeds using genome-wide association and linkage mapping.

Isoflavone, a secondary metabolite produced by Glycine max (L.) Merr. (soybean), is valuable for human and plant health. The genetic architecture of soybean isoflavone content remains unclear, however, despite several mapping studies. We generated genomic data for 200 soybean cultivars and 150 recombinant inbred lines (RILs) to localize putative loci associated with soybean seed isoflavone content. Using a genome-wide association study (GWAS), we identified 87 single-nucleotide polymorphisms (SNPs) that were significantly associated with isoflavone concentration. Using linkage mapping, we identified 37 quantitative trait loci (QTLs) underlying the content of four isoflavones found in the RILs. A major locus on chromosome8 (qISO8-1) was co-located by both the GWAS and linkage mapping. qISO8-1 was fine mapped to a 99.5-kb region, flanked by SSR_08_1651 and SSR_08_1656, in a BC2 F5 population. GmMPK1, encoding a mitogen-activated protein kinase, was identified as the causal gene in qISO8-1, and two natural GmMPK1 polymorphisms were significantly associated with isoflavone content. Overexpression of GmMPK1 in soybean hairy roots resulted in increased isoflavone concentrations. Overexpressing GmMPK1 in transgenic soybeans had greater resistance to Phytophthora root rot, suggesting that GmMPK1 might increase soybean resistance to biotic stress by influencing isoflavone content. Our results not only increase our understanding of the genetic architecture of soybean seed isoflavone content, but also provide a framework for the future marker-assisted breeding of high isoflavone content in soybean cultivars.

Heterosis and combining ability estimates in isoflavone content using different parental soybean accessions: wild soybean, a valuable germplasm for soybean breeding.

Isoflavone, a group of secondary metabolites in soybean, is beneficial to human health. Improving isoflavone content in soybean seeds has become one of the most important breeding objectives. However, the narrow genetic base of soybean cultivars hampered crop improvement. Wild soybean is an extraordinarily important gene pool for soybean breeding. In order to select an optimal germplasm for breeding programs to increase isoflavone concentration, 36 F1 soybean progenies from different parental accessions (cultivars, wild, Semi-wild and Interspecific) with various total isoflavone (TIF) concentration (High, Middle, Low) were analyzed for their isoflavone content. Results showed that male parents, except for Cultivars, showed positive GCA effects. In particular, wild soybean had higher positive GCA effects for TIF concentration. Both MP and BP heterosis value declined in the hybrid in which male parents were wild soybean, semi-wild soybean, interspecific offspring and cultivar in turn. In general, combining ability and heterosis in hybrids which had relative higher TIF concentration level parents showed better performance than those which had lower TIF concentration level parents. These results indicated characteristics of isoflavone content were mainly governed by additive type of gene action, and wild relatives could be utilized for breeding of soybean cultivars with this trait. A promising combination was found as the best potential hybrid for isoflavone content improvement.

Quantitative trait loci analysis of individual and total isoflavone contents in soybean seeds

Soybean isoflavones play diverse roles in human health, including cancers, osteoporosis, heart disease, menopausal symptoms and pabulums. The objective of this study was to identify the quantitative trait loci (QTL) associated with the isoflavones daidzein (DC), genistein (GeC), glycitein (GlC) and total isoflavone contents (TIC) in soybean seeds. A population of 184 F2:10 recombinant inbred lines derived from a 'Xiaoheidou' x 'GR8836' cross was planted in pot and field conditions to evaluate soybean isoflavones. Twenty-one QTL were detected by composite interval mapping. Several QTL were associated with the traits for DC, GeC, GlC and TIC only. QDGeGlTIC4_1 and QDGlTIC12_1 are reported first in this study and were associated with the DC, GeC, GlC and TIC traits simultaneously. The QTL identified have potential value for marker-assisted selection to develop soybean varieties with desirable isoflavone content.

Augmentation of major isoflavones in Glycine max L. through the elicitor-mediated approach

Abstract - Isoflavone content in soybean seeds was enhanced by the elicitor-mediated approach under field conditions through the floral application of abiotic elicitors-salicylic acid, methyl jasmonate and biotic elicitors-Aspergillus niger and Rhizopus oligosporus. Among isoflavones, daidzein and glycitein were found to be highly responsive to elicitors, with an increase of 53.7% and 78.7%, respectively as compared to control. Highest total isoflavone content (1276.4 mg g-1 of seeds) was observed upon the administration of 0.1 mMsalicylic acid, which is 92.7% higher than in control. This study would be valuable for augmentation of the isoflavone content in soybean seeds in field grown plants for better nutraceutical potential.

Factors Affecting Isoflavone Content in Soybean Seeds Grown in Thailand

Soybeans are the most common source of isoflavones in human foods. The objectives of this study were to determine the effects of Thai soybean variety, planting date, physical seed quality, storage condition, planting location, and crop year on isoflavone content, as well as to analyze the relationship between seed viability and isoflavone content in soybean seeds grown in Thailand. Isoflavone content in Thai soybeans varied considerably depending on such factors as variety, physical seed quality, crop year, planting date (even in the same crop year), and planting location. Most varieties (except for Nakhon Sawan 1 and Sukhothai 1) had significantly higher isoflavone content when planted in early rather than in late dry season. Additionally, seed viability as well as long-term storage at10∘Cor at ambient condition seemed unlikely to affect isoflavone content in Thai soybean varieties. Isoflavone content in soybean seeds grown in Thailand depends on multiple genetic and environmental factors. Some varieties (Nakhon Sawan 1 and Sukhothai 1) exhibited moderately high isoflavone content regardless of sowing date. Soybeans with decreased seed viability still retained their isoflavone content.

Identification of QTL underlying isoflavone contents in soybean seeds among multiple environments

Soybean isoflavones are valued in certain medicines, cosmetics, foods and feeds. Selection for high-isoflavone content in seeds along with agronomic traits is a goal of many soybean breeders. The aim of the study was to identify the quantitative trait loci (QTL) underlying seed isoflavone content in soybean among seven environments in China. A cross was made between 'Zhongdou 27', a soybean cultivar with higher mean isoflavone content in the seven environments (daidzein, DZ, 1,865 microg g(-1); genistein, GT, 1,614 microg g(-1); glycitein, GC, 311 microg g(-1) and total isoflavone, TI, 3,791 microg g(-1)) and 'Jiunong 20', a soybean cultivar with lower isoflavone content (DZ, 844 microg g(-1); GT, 1,046 microg g(-1); GC, 193 microg g(-1) and TI, 2,061 microg g(-1)). Through single-seed-descent, 130 F(5)-derived F(6) recombinant inbred lines were advanced. A total of 99 simple-sequence repeat markers were used to construct a genetic linkage map. Seed isoflavone contents were analyzed using high-performance liquid chromatography for multiple years and locations (Harbin in 2005, 2006 and 2007, Hulan in 2006 and 2007, and Suihua in 2006 and 2007). Three QTL were associated with DZ content, four with GT content, three with GC content, and five with TI content. For all QTL detected the beneficial allele was from Zhongdou 27. QTL were located on three (DZ), three (GC), four (GT) and five (TI) molecular linkage groups (LG). A novel QTL was detected with marker Satt144 on LG F that was associated with DZ (0.0014 > P > 0.0001, 5% < R (2) < 11%; 254 < DZ < 552 microg g(-1)), GT (0.0027 > P > 0.0001; 4% < R (2) < 9%; 262 < GT < 391 microg g(-1)), and TI (0.0011 > P > 0.0001; 4% < R (2) < 15%; 195 < TI < 871 microg g(-1)) across the various environments. A previously reported QTL on LG M detected by Satt540 was associated with TI across four environments and TI mean (0.0022 > P > 0.0001; 3% < R (2) < 8%; 182 < TI < 334 microg g(-1)) in China. Because both beneficial alleles were from Zhongdou 27, it was concluded that these two QTL would have the greatest potential value for marker-assisted selection for high-isoflavone content in soybean seed in China.

Effect of temperature and water availability during late maturation of the soybean seed on germ and cotyledon isoflavone content and composition

AbstractBACKGROUND: Isoflavone content in soybean seeds is strongly influenced by both environment and genotype. However, little is known about the effect of environment and genotype on isoflavones in germ versus cotyledons. To determine the effect of temperature and soil moisture status during soybean seed development on seed isoflavone concentration and composition, a set of two French and three US cultivars of similar maturity were grown in the greenhouse. At the R6 growth stage, plants were subjected to one of three night/day temperature regimes (13/23°, 18/28° or 23/33 °C) in either optimal or sub‐optimal soil water conditions.RESULTS: In cotyledons, a three‐ to six‐fold variation in total isoflavone content was observed between the high and low temperature treatments, whereas the germ contents had less than a two‐fold variation. Soil water supply had less effect than temperature on the isoflavone contents and compositions. In both seed parts, the isoflavone concentrations were highly dependent on the cultivar.CONCLUSION: These results show that isoflavone content and composition in cotyledon and germ are unrelated and it should be possible to independently manipulate these seed traits through plant breeding and crop management systems. Copyright © 2007 Society of Chemical Industry

Genetic Analysis of Embryo, Cytoplasm and Maternal Effects and Their Environment Interactions for Isoflavone Content in Soybean [ Glycine max (L.) Merr.

Abstract Soybean seed products contain isoflavones (genistein, daidzein, and glycitein) that display biological effects when ingested by humans and animals. These effects are species, dose and age dependent. Therefore, the content and quality of isoflavones in soybeans is a key factor to the biological effect. Our objective was to identify the genetic effects that underlie the isoflavone content in soybean seeds. A genetic model for quantitative traits of seeds in diploid plants was applied to estimate the genetic main effects and genotype x environment ( GE) interaction effects for the isoflavone content ( IC) of soybean seeds by using two years experimental data with an incomplete diallel mating design of six parents. Results showed that the IC of soybean seeds was simultaneously controlled by the genetic effects of maternal, embryo, and cytoplasm, of which maternal genetic effects were most important, followed by embryo and cytoplasmic genetic effects. The main effects of different genetic systems on IC trait were more important than environment interaction effects. The strong dominance effects on isoflavone from residual was made easily by environment conditions. Therefore, the improvement of the IC of soybean seeds would be more efficient when selection is based on maternal plants than that on the single seed. Maternal heritability (65.73%) was most important for IC, followed by embryo heritability (25.87%) and cytoplasmic heritability (8.39%). Based on predicated genetic effects, Yudou 29 and Zheng 90007 were better than other parents for increasing IC in the progeny and improving the quality of soybean. The significant effects of maternal and embryo dominance effects in variance show that the embryo heterosis and maternal heterosis are existent and uninfluenced by environment interaction effects.

Abstracts of Nippon Dojo-Hiryogaku Zasshi

Abstracts of Nippon Dojo-Hiryogaku Zasshi

Difference by Soybean Cultivar and Harvest Year of Isoflavone Content in Soybean Seeds

Difference by Soybean Cultivar and Harvest Year of Isoflavone Content in Soybean Seeds

Inheritance of isoflavone contents in soybean seeds

We studied the genetic basis of isoflavone content inheritance in soybean seeds. The progenitors BARC-8 (low isoflavone content), IAC-100 (high isoflavone content), the F1 and F2 populations derived from reciprocal crosses, and backcross populations were analyzed for isoflavone content and composition. Six isoflavones were detected: daidzin (DZ), genistin (GT), glycitin (GC), malonyldaidzin (MDZ), malonylgenistin (MGT) and malonylglycitin (MGC). DZ, GT, MDZ and MGT contents were influenced by the cytoplasm and the nuclear genes of the maternal parent. For this reason, a genetic model was considered that included the cytoplasmic effect and epistasis between nuclear and cytoplasmic genes. Except for GT, the additive effect was the most important one. For GT content the cytoplasmic effect was the most important. Except for MDZ, the epistatic effects were significant for all the isoflavone forms. Our data indicate that genetic improvement for these traits should explore the additive genetic variances in superior lines or the cytoplasmic effect and the epistatic interactions between cytoplasmic and nuclear genes to obtain the largest selection gains.

Mapping QTL for Individual and Total Isoflavone Content in Soybean Seeds

Mapping QTL for Individual and Total Isoflavone Content in Soybean Seeds

Agronomic Performance of Recombinant Inbred Line Populations Segregating for Isoflavone Content in Soybean Seeds

Soybean [Glycine max (L.) Merrill] seeds contain isoflavones, which have been associated with positive health effects in human adults but a negative effect on infants. Increasing or decreasing isoflavone content in the seed would be desirable; however, it is not known what impact this would have on agronomic and other seed quality traits. The main objective of this study was to determine if isoflavone content in soybean seeds was associated with changes in agronomic and seed quality traits. Recombinant inbred lines (RILs) with “high” (n = 35), “intermediate” (n = 35), and “low” (n = 35) isoflavone content, were selected from three F4:5 populations grown in 2000 and planted at three locations in southern Ontario in 2002. There were significant differences among populations, environments, and their interaction for isoflavone content. “High” and “low” phenotypic classes were significantly different for maturity in all three populations. Despite a positive correlation between yield and isoflavones, several RILs with decreased isoflavone content (970 μg g−1) were identified with yields (4222 kg ha−1) comparable to high‐yielding cultivars. Isoflavone content had minimal effects on oil content, seed quality, and weight. Population 1 showed a significant negative association between isoflavone and protein content, whereas Pop. 2 and Pop. 3 did not. RILs were identified with high isoflavone and protein content ranging from 1746 to 1851 μg g−1 and 431 to 442 g kg−1, respectively. It was possible to develop soybean with desirable isoflavone content in the seed and superior agronomic and seed quality traits.

Mapping QTL for Individual and Total Isoflavone Content in Soybean Seeds

Dietary intake of isoflavones has been shown to reduce the risk of several major diseases in humans. Therefore, breeding soybean [Glycine max (L.) Merrill] seeds with desirable isoflavone content would be beneficial to the food and health industries, but the environmental sensitivity of the trait complicates phenotypic selection. The objective of this study was to identify quantitative trait loci (QTL) and epistatic interactions associated with isoflavone contents in soybean seeds. A population of 207 F4:6 recombinant inbred lines (RILs) was produced from the cross ‘AC756’ × ‘RCAT Angora’. The population was phenotyped at two locations in Ontario, Canada, and genotyped by means of 99 polymorphic SSR markers. A significant genotype × environment interaction was found. Seventeen QTLs were detected (P &lt; 0.01) by single‐factor ANOVA. Individual loci explained up to 10.5% (P &lt; 0.0001) of the phenotypic variation. Interval mapping and composite interval mapping identified nine genomic regions (LGs A1, C2, D1a, F, G, H, J, K, and M) associated with isoflavone contents. Some QTL associated with agronomic or seed quality traits mapped to the same regions as those for individual isoflavone contents on LGs A1, C2, F, J, K, M, and N. Twenty‐three epistatic interactions were detected for isoflavones. Multiple locus models explained up to 25.0% (P &lt; 0.0001) of the phenotypic variation without epistasis and up to 35.8% (P &lt; 0.0001) with it. The QTL identified in this study could be useful for developing soybean varieties with desirable isoflavone content in the seed through marker‐assisted selection (MAS).

Analysis of phenolic compounds and isoflavones in soybean seeds (Glycine max (L.) Merill) and sprouts grown under different conditions

Soybeans (Glycine max (L.) Merill) are popularly known as a healthy food in many Asian countries and are mostly consumed as soymilk, tofu, and fermented products such as miso, temph, and sufu. The objective of this study was to determine the variation and composition of phenolic compounds and isoflavone contents in soybean seeds [Glycine max (L.) Merill] and sprouts [Kongnamul] grown under dark conditions (producing yellow soybean sprouts) and in green and yellow boxes (producing green soybean sprouts). In seven soybean cultivars, the total phenolic content ranged from 6.67 μg−1 in Pureunkong to 72.33 μg−1 in Poongsannamulkong. The average total phenolic content in the green soybean sprouts (48.33 μg−1) was higher than in the yellow soybean sprouts (29.75 μg−1). The total phenolic content in the yellow soybean sprouts varied from 9.88 μg−1 to 47.71 μg−1, and the total phenolic content in the green soybean sprouts varied from 29.21 μg−1 to 79.70 μg−1. Only four phenolic compounds, p-hydroxybenzoic acid, salicylic acid, p-coumaric acid, and ferulic acid, were detected in all soybean cultivars. Syringic acid was not detected in yellow soybean sprouts, and myricetin was only detected in yellow soybean sprouts (4.65 μg−1) from the Pureunkong cultivar grown under dark conditions. The total isoflavone content in soybean seeds ranged from 2.1 μg−1 in Sowonkong to 33.0 μg−1 in Pureunkong, and the mean total isoflavones was 10.61 μg−1. Green soybean sprouts had higher average total isoflavones (1389.4 μg−1) than yellow soybean sprouts (559.2 μg−1), and the total isoflavone content was highest in the Pureunkong yellow soybean sprouts (756.3 μg−1) and the Sowonkong green soybean sprouts (2791.6 μg−1). In soybean sprouts, the higher the (malonyl)-daidzin or (malonyl)-genistein content, the higher the total isoflavone level. Our study suggests that producing soybean sprouts enriched in isoflavones under coloured-light sources is feasible.

Genetic parameters relating isoflavone and protein content in soybean seeds

Isoflavones are a class of compounds present in high amounts in soybean seeds, which can be used for prevention and treatment of several chronic diseases. Proteins present in soybean seeds are the basis for the high nutritional value and versatility of this leguminous species in animal and human feeding. The main goals of this work were to estimate heritabilities for isoflavone contents in soybean seeds and the correlation between isoflavone and protein contents. Commercial variety IAC-100 (high isoflavone and normal protein contents) and the line BARC-8 (low isoflavone and high protein contents) were crossed, and one single F1 plant derived 97 F2 seeds, which were used to obtain F3 seeds. A sample of F3 seeds from each F2 plant was used for isoflavone determination by HPLC and protein by the Kjeldahl method. Six isoflavone forms were detected: daidzin, genistin, glycitin, malonyldaidzin, malonylgenistin and malonylglycitin. Total isoflavone contents ranged from 427.92 to 965.89 μg per gram of dry seed and the protein content ranged from 45.17 to 34.95% in BARC-8 and IAC-100, respectively. Our results indicate that it is possible to select for high isoflavone content in early breeding generations because the broad sense heritabilities for the contents of the various isoflavone forms were higher than 90%. In addition, high correlation values among the contents of the individual isoflavone forms were observed (between 0.80 and 0.98). However, negative correlation values were obtained between isoflavone and protein contents, ranging from −0.51 to −0.37 for the different isoflavone forms. The correlation value of −0.47 between total isoflavone and protein contents confirmed the negative correlation between these two parameters, as reported by other authors.

Effects of year, site, genotype and their interactions on various soybean isoflavones

The popularity of soybeans is increasing as soybean products are now regarded as healthy foods, partly due to the isoflavones contained in their seeds. This study was initiated to study the isoflavone content in soybean seeds as influenced by genotype, year, site and their interactions. Fifteen cultivars were grown at three sites (Seoul, Suwon and Kyongsan) in Korea in 1998–2000, and harvested seeds were measured to determine the content of nine different isoflavones. This study led to the following conclusions. The main environmental effects (year and year-by-site interactions) and genotype-by-environment interactions (genotype-by-year and genotype-by-year-by-site interactions) were the most important sources of variation for the content of various isoflavones in soybean seeds. Significant differences among genotypes in isoflavone content exist that can only be reliably detected through multi-site and multi-year tests. The genotype ‘Geomjeong 1’ had consistently higher total isoflavone content. While the genotype ‘Jangyeob’ also had high total isoflavone content, it was less stable than ‘Geomjeong 1’. There were no major genetically determined negative associations among the isoflavones, except for that between glycitin (GLY) and malonylgenistin (MGIN). On the contrary, a strong negative environmental association was observed between genistein (GEIN) (along with glycitein (GLIEN)) and daidzin (DIN) (along with genistin (GIN)). Both genetically and environmentally, total isoflavone content was most closely associated with malonylgenistin (MGIN).