Zinc absorption from low phytic acid genotypes of maize (Zea mays L.), Barley (Hordeum vulgare L.), and Rice (Oryza sativa L.) assessed in a suckling rat pup model

Dietary phytic acid is a major causative factor for low Zn bioavailability in many cereal- and legume-based diets. The bioavailability of Zn in seed of low phytic acid (lpa) variants of maize ( Zea mays L.), rice ( Oryza sativa L.), and barley ( Hordeum vulgare L.) was evaluated using a suckling rat pup model. Suckling rat pups (14 days old, n = 6-8/treatment) were fasted for 6 h and intubated with (65)Zn-radiolabeled suspensions prepared using seed produced by either wild-type (normal phytic acid) or lpa genotypes of each cereal. Test solutions were radiolabeled overnight (all genotypes) or immediately prior to intubation (barley genotypes). Pups were killed 6 h postintubation and tissues removed and counted in a gamma counter. Zn absorption was low from wild-type genotypes of maize (21, 33%) and rice (26%), and phytic acid reduction resulted in significantly higher Zn absorption, 47-52 and 35-52%, respectively. Zn absorption from wild-type barley incubated overnight was high (86-91%), and phytate reduction did not improve Zn absorption (84-90%), which is likely due to endogenous phytase activity. When the wild-type barley solutions were prepared immediately before intubation, Zn absorption was significantly lower (63, 78%) than from the lpa cultivars (92, 96%). Variation in seed or flour phenolic acid levels did not affect Zn absorption. Differences in seed Zn levels did not substantially affect Zn absorption. Thus, when phytic acid is abundant in a diet, it has a larger effect on Zn absorption than the level of Zn. Therefore, reducing the phytic acid content of staple cereal grains may contribute to enhancing Zn nutrition of populations consuming these staple foods.     

Comparison of the phosphorus and mineral concentrations in bran and abraded kernel fractions of a normal barley (Hordeum vulgare) cultivar versus four low phytic acid isolines

Phytic acid consists of 65-80% of the total phosphorus (P) in cereal grains. Its salts are concentrated in the germ and aleurone layers, which are typically removed during milling. We hypothesize that concentrations of different types of P and minerals in milled products will be greatly altered in low phytic acid (lpa) barleys. Seeds of cv. Harrington (control) and four lpa isolines-lpa1-1, lpa2-1, lpa3-1, and M955-were abraded by a laboratory method into five surface layer and four remaining kernel fractions. Results show that phytic acid in the four lpa lines ranged from 75% to 5% of the control. The decrease in phytic acid P concentration was matched almost equally by an increase in inorganic P, so that the rest of P (the sum of all P-containing compounds other than phytic acid P and inorganic P) and total P levels remained relatively unchanged among the five genotypes. These trends were also observed for the processed fractions. The major mineral elements in barley seeds were P, K, Mg, S, and Ca, while minor ones were Fe, Zn, Mn, Cu, and Ba. All types of P and other minerals measured were generally concentrated in the outer layers of the grain. Although there were substantial differences in mineral contents of bran fractions among genotypes, the level of phytic acid P had little effect on mineral contents in whole or abraded kernels. One major exception was Fe, which had the highest level in all tissues of M955 genotype. The above findings were all confirmed by analyzing another set of barley samples grown in a different environment. Thus, in general, breeding lpa barleys does not lead to reduced mineral contents in whole grains or elevated mineral levels in milled products.     

The hypocholesterolemic activity of transgenic rice seed accumulating lactostatin, a bioactive peptide derived from bovine milk β-lactoglobulin

Lactostatin is a novel pentapeptide (IIAEK) derived from bovine milk β-lactoglobulin with greater hypocholesterolemic activity than β-sitosterol, the drug commonly used to treat hypercholesterolemia. We developed transgenic rice expressing lactostatin as a fusion protein with seed storage protein (SSP) glutelins under the control of three different endosperm-specific promoters. Lactostatin accumulated in transgenic rice seed at approximately 1.6 mg/g seeds (dry seeds) without any apparent influence on seed traits such as endogenous SSP expression levels or alterations in the intracellular structures of endosperm cells. Short-term (three day) oral administration of the glutelin fraction containing lactostatin (namely three times of 300 mg/kg body weight/day) extracted from transgenic rice seeds resulted in hypocholesterolemic activity in rats; namely, the serum low-density-lipoprotein (LDL) cholesterol level was significantly reduced accompanied by a significant increase in beneficial serum high-density-lipoprotein (HDL) cholesterol.     

Optimizing Seed Sample Size for Zinc and Iron Analysis of Wild and Cultivated Lentil

Zinc and iron deficiencies affect billions of people globally and have direct impact on human health. Zinc and iron concentrations in plant materials are commonly analyzed by flame atomic absorption spectrometry (F-AAS). This research describes the optimal analysis method for precise zinc (Zn) and iron (Fe) analysis of seeds from the seven species of genus Lens. Estimation of Zn and Fe concentration in whole lentil seeds by F-AAS is destructive, using nitric acid digestion of seeds prior to instrument analysis. The procedure proposed for the determination of Zn and Fe concentration uses the minimum amount of lentil seed of all lentil species with suitable standard reference materials. The relative standard deviations of the method were about 5% for both Zn and Fe. The minimum sample amount 0.3 g of wild and 0.5 g of cultivated lentil seed samples was identified for accurate and precise estimation of Zn and Fe concentration.     

花生种子特异启动子AHSSP1的克隆及功能分析

为丰富花生种子特异启动子资源,本研究利用PCR技术在花生基因组中克隆了种子贮藏蛋白基因PSC32的启动子AHSSP1,利用半定量RT-PCR检测了PSC32基因表达模式,借助NewPLACE在线分析了AHSSP1序列中存在的顺式作用元件,并构建了AHSSP1驱动GUS报告基因的表达载体,经农杆菌转化获得转基因拟南芥,经GUS组织化学染色鉴定了该启动子的功能。结果表明,PSC32基因957 bp长的启动子AHSSP1序列具备种子特异表达启动子特有的3个RY REPEAT元件。半定量RT-PCR分析发现,PSC32基因在花生成熟种子中表达,而在饱果成熟期根、茎、叶片、花、入土前的果针、成熟种子的果壳中均不表达。GUS组织化学染色发现,转基因拟南芥成熟种子以及萌发种子的子叶、下胚轴和胚根均能够被染上蓝色;长出真叶后,子叶和下胚轴仍能被染色,而根和真叶不能被染上蓝色;成年期转基因拟南芥的叶片也不能被染上蓝色。而野生型拟南芥整个生长时期均不能被染上蓝色。以上现象说明AHSSP1是一个种子特异启动子。本研究丰富了花生种子特异启动子的资源,对花生籽仁品质改良或以花生籽仁作为“生物反应器”的研究具有重要的应用价值。     

Antioxidant activity and inhibition of lipid peroxidation in germinating seeds of transgenic soybean expressing OsHGGT

Tocochromanols are potent lipid-soluble antioxidants and essential nutrients for human health. Genetic engineering techniques were used to develop soybeans with enhanced vitamin E levels, including tocotrienols, which are not found in soybean. The gene encoding rice homogentisate geranylgeranyl transferase (HGGT) was overexpressed in soybeans using seed-specific and constitutive promoters. The association between abundance of vitamin E isomers and antioxidant activity was investigated during seed germination. With the exception of β-tocotrienol, all vitamin E isomers were detected in germinating seeds expressing OsHGGT. The antioxidant properties of germinating seed extracts were determined using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azinobis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radicals and lipid peroxidation (TBARS). Compared with intact wild-type seeds, transgenic seeds showed increases in radical scavenging of 5.4-17 and 23.2-35.3% in the DPPH and ABTS assays, respectively. Furthermore, the lipid peroxidation levels were 2.0-4.5-fold lower in germinating seeds from transgenic lines than in wild-type seeds. Therefore, it appears that the antioxidant potential of transgenic oil-producing plants such as soybean, sunflower, and corn may be enhanced by overexpressing OsHGGT during seed germination.     

Biochemical safety evaluation of transgenic rice seeds expressing T cell epitopes of Japanese cedar pollen allergens

Transgenic rice seeds, which express a hybrid peptide comprising seven predominant human T cell epitopes (7Crp) derived from Japanese cedar pollen allergens, have been shown to function as an effective edible vaccine for the control of pollen allergen-induced responses. In this study, we characterized biochemical properties of transgenic seeds expressing the 7Crp peptide. The levels of chemical compositions, such as carbohydrate, protein, lipid, amino acid, fatty acid, mineral, and vitamin, were substantially equivalent between transgenic 7Crp and its nontransgenic counterpart seeds. The contents of three major allergenic proteins in transgenic seeds were not enhanced by expression of the 7Crp peptide when compared with those of nontransgenic seeds. The 7Crp peptide expressed in seeds was susceptible to simulated gastric/intestinal fluids. N-Glycosylation was not observed in the 7Crp peptide sequence. These results indicate that transgenic 7Crp seeds are substantially equivalent to nontransgenic parental seeds except for the presence of the 7Crp peptide. Keywords: Food safety assessment; transgenic rice seed; edible vaccine; peptide-based immunotherapy; Japanese cedar pollinosis.     

Effects of Four Independent Low‐Phytate Mutations in Barley (Hordeum vulgare L.) on Seed Phosphorus Characteristics and Malting Quality

Conversion of the seed phosphorus storage compound phytic acid, which is poorly digested by nonruminants, to available forms of phosphorus will have nutritional and environmental benefits. Low‐phytate (LP) barley (Hordeum vulgare L.) cultivars are in development and their commercialization will be facilitated by understanding their phosphorus profiles and malting quality. To study these issues, LP and normal types derived from mutagenized populations of barley cultivar Harrington (sets of sib lines homozygous for the wild‐type [WT] allele, or for one of four low‐phytic acid mutations, lpa1‐1, lpa2‐1, lpa3‐1, or M955), were developed through backcrosses to Harrington. Grain was produced in irrigated and rain‐fed environments. WT phosphorus profiles were similar to those of Harrington, suggesting that the major variable was the presence or absence of mutant alleles. All mutations conferred increased inorganic phosphorus. Total P was reduced for lpa1‐1. Phosphorus profiles were relatively stable across environments, which will facilitate the inclusion of LP barley in animal rations. Utilization of LP cultivars for malting may be difficult, as the LP trait was associated with substantial reductions in diastatic power. All mutations, except for lpa2‐1, affected wort β‐glucan levels, which could not be attributed to altered grain β‐glucan levels.     

大豆低植酸突变体籽粒的抗氧化性分析

植酸具有较强的抗氧化能力,对作物籽粒的耐储性和活力均具有重要作用,但其作用机制尚不明确。为揭示大豆低植酸突变体和野生型亲本中抗氧化代谢产物的差异,本研究以低植酸突变体Gm-lpa-ZC-2、Gm-lpa-TW-1、Gm-lpa-TW-1-M,以及野生型亲本浙春3号、台湾75为材料,分析大豆籽粒发育过程中植酸含量对抗氧化能力的影响。结果表明,大豆籽粒发育过程中的总抗氧化能力受过氧化物酶和过氧化氢酶活力的影响较大,而非酶类氧化剂谷胱甘肽对总抗氧化能力影响较小。随着籽粒的成熟,脂质氧化物、丙二醛与蛋白羰基化产物的含量逐渐增加。低植酸突变体Gm-lpa-ZC-2、Gm-lpa-TW-1-M和亲本浙春3号、台湾75的总抗氧化能力较强,且籽粒活力也较高;而低植酸突变体Gm-lpa-TW-1的总抗氧化能力最弱,且籽粒活力也最弱,说明大豆籽粒抗氧化水平与籽粒活力呈正相关,但与植酸含量无相关关系。由此推测植酸并非影响大豆籽粒抗氧化能力和活力的直接因素。本研究结果为进一步探索低植酸作物的籽粒活力下降机制,培育高籽粒活力低植酸大豆品种提供了参考。     

Influence of Foliar Iron Fertilization Rate on the Breakage Susceptibility of Wheat Seeds

The objectives were to determine the effect of different levels of foliar iron fertilization on the some physical properties and breakage susceptibility of wheat seed. Foliar iron treatments were combinations of three fertilization rates [0 (control), 1.2 and 2 L ha^?1, Fusin] at three replications. The harvested seeds were then subjected to impact energies of 0.1 and 0.2 J, at moisture contents of 8.5, 15, 20 and 25% (w.b.), using an impact test apparatus. Results indicated that the values of the seed physical properties increased with increasing iron rate. Iron fertilizer rate, moisture content and the interaction between two variables significantly influenced breakage susceptibility of wheat seeds at the 1% probability level (P < 0.01). Resistance to the breakage of wheat seeds increased following a polynomial relationship with increase in the foliar iron rate. Increasing the rate of foliar iron from 0 to 2 L ha^?1 caused a significant decrease in the mean values of damage by a factor of 1.8 from 66.188 to 36.688%. As the moisture content of the seeds increased from 8.5 to 25%, the amount of the percentage breakage of seeds decreased, as a polynomial. The maximum rate of decrease in the damage to seeds, with increasing moisture content, was obtained at higher iron fertilizer rates.     

Effect of placement of urea and coated urea fertilizers on yield and quality of soybean (Glycine max (L.) Merr.) seeds

The objective of the present study was to record the seed yield and to examine visually the quality of soybean seeds cultivated under different types and placements of urea fertilizers. In addition to the conventional fertilizer application (including ammonium sulfate 16 kg N ha^-1 broadcasting (100 kg N ha^-1 of urea (0B) and X00-d type coated urea CU-100 (CUB), and deep placement (100 kg N ha^-1) of urea (UD) and 100-d type coated urea CU-100 (CUD) was conducted in separate plots in a paddy field converted to an upland field located at Shindori Experimental Station of Niigata University. Soybean plant growth was periodically analyzed and the quality of harvested seeds was also visually examined (hereafter referred to as “visual quality”). It was found that the deep placement treatments were more conducive 1o nitrogen (N₂)fixation, based on the relative mreide N concentration in the xylem sap, which is a good indicator of N~fixation by soybean. Also the total seed yield was the highest in CUD (82 g plant^-1) and 0D (81 g plant^-1), compared to the control (62 g plant^-1), UB (68 g plant^-1), and CUB (68 g plant^-1). The visual quality of harvested seeds showed that CUD enhanced the quality of seeds compared to the other treatments, in which the percentage of good quality seeds, hereafter referred to as "good seeds," based on the dry weight was 51 (control), 65 (K3B), 61 (CUB), 61 (0D), and 6696 (CUD). In terms of diseased seeds, the percentage of turtle wrinkle and broken seed coats was found to decrease by N application compared to the control. Thus, it is suggested that N fertilization management is important for maximum yield of soybean as well as for the enhancement of seed quality.     

Extractable amounts of trans-resveratrol in seed and berry skin in Vitis evaluated at the germplasm level

Extractable amounts of resveratrol in berry skins and seeds were studied in 120 grape (Vitis) germplasm cultivars during two consecutive years to determine the distribution of resveratrol among the main grape genotypes. Interspecific rootstock cultivars had much higher extractable amounts of resveratrol in skin and seed than all other grape genotypes studied in both years. Extremely high extractable amounts of resveratrol in berry skins [>100 microg g(-1) of skin fresh weight (FW)] and seeds (>20 microg g(-1) of seed FW) were observed on two rootstock cultivars obtained from hybrids of V. monticula x V. riparia. Extractable amounts of resveratrol in berries of rootstock cultivars that are the descendants of V. riparia were also very high. The cultivated European type (V. vinifera) cultivars and their hybrids with V. labrusca had relatively low levels of extractable resveratrol in berry skin and seed, and the extractable amounts of resveratrol in berry skin and seeds were, with a few exceptions, <2 microg g(-1) of skin or seed FW. Extractable amounts of resveratrol in berry skin and seeds were closely related with fruit traits or purpose of uses and climate. Significantly higher extractable amounts of resveratrol in berry skin were found in seeded cultivars than in seedless ones, in both berry skin and seeds in winemaking grapes than in table grapes, and in red grapes than in green ones. Moreover, rainfall during fruit development resulted in higher extractable amounts of resveratrol in berry skin, whereas resveratrol synthesis and accumulation in grape seeds were not related to climate change.     

Effects of nano-fertilizers on physiological and yield characteristics of pinto bean cultivars under water deficit stress

Abstract

In order to evaluate the effects of water deficit stress and foliar application of zinc (Zn) and iron (Fe) nanoparticles on physiological characters and seed yield of pinto bean, an experiment was designed as a split factorial design based on randomized complete blocks with three replications in two growing seasons (2016–2017 and 2017–2018). Treatments were included water deficit stress (normal irrigation and water deficit stress in 50% flowering), foliar application of nano-fertilizers (control, nano-Zn (1.5?g L^?1), nano-Fe (2?g L^?1) and combination of nano-Zn and nano-Fe) and four cultivars of pinto bean (Sadri, Coosha, Cos16, and Ghaffar). The results showed that the soluble sugars and proline content was increased under water deficit. Water deficit stress through decreasing chlorophyll and relative water content of leaves as well as the iron and zinc content of seeds, decreased seed yield and quality. The application of nano-fertilizers of zinc and iron enhanced antioxidant enzymes activity, proline and soluble sugars content as well as leaf area. Also applied nano-fertilizers improved seed quality in terms of protein content. According to obtained results the effect of foliar spray of nano-fertilizers on iron and zinc content of seeds regards to bean cultivars was different. It was concluded that the foliar application of iron combined zinc nano-fertilizers can be useful in pinto bean cultivars under water deficit stress. In both normal and water deficit Cos16 cultivar showed the better amount of studied characteristics compared to other cultivars. The results of cluster analysis of these cultivars confirmed the superiority of Cos16 cultivar.     

稻麦油兼用高速气送式集排器型孔轮设计与试验

针对水稻、小麦、油菜种子播量要求和外形尺寸差异大且稻麦种子流动性不足，导致气送式集排器兼用性不足、高速供种稳定性不佳的问题，该研究设计了一种稻麦油兼用型孔轮。阐述了高速供种工作原理，开展了供种环节充种、携种、投种阶段力学分析，基于最速降线原理设计了型孔壁面曲线，运用EDEM仿真对比分析了不同转速条件下种群运动状态。通过台架试验明确供种速率和供种稳定性较优的转速范围，并构建了稻麦油供种速率回归模型。台架试验结果表明：对于水稻和小麦种子，型孔轮个数16、供种转速30～50 r/min和50～70 r/min时，供种速率稳定性变异系数小于1%，水稻、小麦的供种速率分别为1050.62～1535.87 g/min和4171.82～5073.76 g/min；对于油菜种子，型孔轮个数为1，供种转速为20～30 r/min时，供种速率稳定性变异系数小于0.5%，供种速率为160.42～227.45 g/min；稻麦油供种速率回归模型预测值与试验值相对误差小于2%。水稻旱直播、小麦、油菜田间播种试验表明，作业速度在8～10 km/h时，集排器总排量稳定性变异系数分别为1.32%、1.16%和1.07%，满足稻麦油兼用播种作业标准要求。研究结果可为高速兼用气送式集排器结构改进提供参考。     

Metabolite profiling of two low phytic acid (lpa) rice mutants

Two low phytic acid (lpa) rice mutant lines, Os-lpa-XS110-1 and Os-lpa-XS110-2, were grown together with their parent wild-type variety Xiushui 110 in four field trials. HPLC analysis of inositol phosphates in the seeds produced demonstrated that compared to the wild-type, the reduction in phytic acid content in Os-lpa-XS110-1 (-46%) was more pronounced than that in Os-lpa-XS110-2 (-23%). Lower inositol phosphates (InsP 3, InsP 4, InsP 5) were not detected in the mutants. The lpa mutants and the wild-type rice were subjected to comparative metabolite profiling by capillary gas chromatography. On average, 34% (Os-lpa-XS110-1) and 42% (Os-lpa-XS110-2) of the detected peaks were statistically significantly different between wild-type and mutants. However, only a few of these differences could be consistently observed for all field trials. Identification and quantification of the consistently different metabolites revealed that contents of myo-inositol and raffinose were increased in Os-lpa-XS110-1 but decreased in Os-lpa-XS110-2 compared to the wild-type. In addition, Os-lpa-XS110-1 exhibited increased levels of galactose and galactinol. Consideration of these metabolic changes in light of the routes involved in the biosynthesis of phytic acid indicated a disturbance in the early biosynthetic pathway of phytic acid in Os-lpa-XS110-2 (similar to the lpa-1 type mutation in maize) and a mutation event affecting phosphorylation of myo-inositol in Os-lpa-XS110-1 (similar to the lpa-3-type mutation).     

Nitrogen fertilization affects yields and storage compound contents in seeds of field-grown soybeans cv Enrei (Glycine max. L) and its super-nodulating mutant En-b0-1 through changing N2 fixation activity of the plants

ABSTRACT

We compared the protein and oil contents, seed yields, and natural abundance of ¹⁵N (σ¹⁵N) of seeds from the plants of the cultivar Enrei, which has moderate nodulating ability (Enrei) with those of its two near-isogenic lines (NILs), a super-nodulating genotype of Enrei, i.e., En-b0-1, and a non-nodulating genotype of Enrei, i.e., En1282. Plants of these three genotypes were grown on four types of field plots with different types of urea coated slow-release nitrogen (N) fertilizers (CUSLNFs) which delivered N in different manners during plant growth . The seed yield of the En1282 plants was similar to that of the Enrei plants but much greater than that of the En-b0-1 plants when the plants were grown on the field to which a CUSLNF with a long lifespan was applied. The amounts of protein per seed were positively correlated with those of oil per seed in the case of En1282 plants irrespective of the field N conditions. The seed protein contents were proportional to the seed weight in both En1282 and Enrei plants. Such a relationship was not observed in the En-b0-1 plants, and the protein and oil contents in the seeds of En-b0-1 plants were negatively correlated with each other. These observations suggested that the N supply to maturing seeds was a key to the protein contents in the En1282 and Enrei plants and that the C supply to maturing seeds was a key to the protein contents in the En-b0-1 plants. The comparison of the σ¹⁵N values, protein contents, and seed yields of seeds from En1282 plants suggested that the Enrei plants assimilated considerable amounts of N from the soil during the late plant growth. We concluded that high N₂ fixation activity depressed the amounts of oil per seed and changed the protein and oil contents in soybean seeds.     

白莲二次航天搭载的选育研究

经二次航天搭载后 ,白莲种子SP1代产生广谱分离 ,其生物习性、形态特征及经济生状等出现较大变异 ,其中花型由单瓣变为重瓣或半重瓣 ,并出现部分种子只长立叶 ,不开花 ,部分种子只开花不结蓬、部分种子结蓬后不能正常成熟的现象 ,也出现种子单缸现蕾 9朵 ,花期始蕾期提前 7～ 2 2d ,种子最大单粒重达 1 85g的优良变异 ,这是采用常规育种很少出现的情况     

点胶-纸带式小粒径种子蔬菜精密播种机设计与试验

针对目前蔬菜机械化播种精度低的问题,该研究设计了一种点胶-纸带式小粒径种子蔬菜精密播种机。通过对蠕动泵胶装置、棘轮点胶装置、排种装置的机构分析,确定了各机构的结构参数,并以导种管长度、导种管截面角度以及窝眼轮转速为试验因素,结合Box-Behnken试验方案进行导种管优化试验。结果表明,当导种管长度为56 mm,截面角度为35°、排种轮转速为30 r/min时,纸带上有效区种子占比达57.23%。以泵胶装置辊子转角和预胶化淀粉与水混合物质量比为试验因素,对直径为1.5～2.0 mm的上海青605种子进行粘附试验。结果表明,当辊子转角为10°,预胶化淀粉与水混合物质量比为1:6时,单粒种子粘附率达97.4%。开展整机对不同品种小粒径蔬菜种子的适应性试验,结果表明,在0.5～1.5 m/s作业速度下,上海青605和四季小白菜的播种单粒率均大于95%,株距变异系数均小于10%。与现有电控锥盘式蔬菜播种机相比,单粒率提高了3.53%,工作效率提高了50%,满足NY/T1143-2006规定的精密播种性能指标要求,该研究可为小粒径种子蔬菜精密播种机的结构设计和优化提供参考。     

Analysis of isoflavones and phenolic compounds in Korean soybean [Glycine max (L.) Merrill] seeds of different seed weights

The seeds of 322 Korean soybean varieties were collected from six different cultivated sites in Korea and classified into three groups based on the 100-seed weight as small, medium, and large. Seeds were analyzed for their concentrations of isoflavones and phenolic compounds. The total average isoflavones in soybean cultivated at Iksan (2.840 micromol g(-1)) and phenolic compounds in soybean grown at Yeoncheon (9.216 micromol g(-1)) and Iksan (9.154 micromol g(-1)) were significantly different (p<0.05). In small and medium seeds of soybeans cultivated at Yeoncheon, Yesan, and Milyang high levels of isoflavones were obtained, whereas soybeans grown in Chuncheon showed the lowest isoflavone concentrations. However, isoflavone concentrations in the large seeds of soybean cultivated at Chuncheon showed the highest level. The soybean cultivated at Yeoncheon had high levels of phenolic compounds in small, medium, and large seeds, whereas the soybean grown at Chuncheon had the lowest. On the other hand, the phenolic concentrations of large soybean cultivated at Milyang were the least. At Yeoncheon, Yesan, and Milyang, the total isoflavone and phenolic compounds levels related to their seed size was significantly different (p<0.05), whereas in the soybean of different sizes cultivated at Chuncheon, the relationship to their seed size was not significantly different. The relationships of total isoflavones and phenolic compounds of small and medium soybean seeds were significantly higher than that of large soybean seeds. The hydroxybenzoic acid group in all sizes of seeds cultivated at six sites in Korea was the major phenolic compound, followed by flavonoid and hydroxycinnamic acid. The total isoflavone concentration was positively correlated with acetylglycoside and negatively correlated with malonylglycoside in the small soybean seeds cultivated at Yeoncheon. In medium soybean seeds cultivated at Yeoncheon, a significantly positive correlation was found between acetylglycoside and glycoside, between aglycone and glycoside, and between aglycone and acetylglycoside, whereas a significantly negative correlation was shown between malonylglycoside and glycoside, between acetylglycoside and malonylglycoside, and between aglycone and malonylglycoside. In large soybean seeds cultivated at Chuncheon, significantly positive and negative correlations were similar to those of medium seeds. The results presented here can improve the understanding of the relationships among the concentrations of individual chemical compounds and each chemical compound group and total chemical compounds in soybeans of different seed sizes from different cultivated sites.