Soy Protein Research(Japan)

37-1

Improvement in Zinc Nutrition and the Memory from Soybean Components

Taiho KAMBE* and Atsushi TAKEDA

Division of Integrated Life Science, Graduate School of Biostudies, Kyoto University, Kyoto 606-8502
Department of Neurophysiology, School of Pharmaceutical Sciences, University of Shizuoka, Shizuoka 422-8526

ABSTRACT
Adequate intake of zinc from the daily diet is indispensable to maintain health, because zinc plays critical roles in a variety of biological processes. Therefore, increased attention is required to improve zinc nutrition and to overcome zinc deficiency. In the small intestine, the zinc transporter, ZIP4, functions as a component that is essential for zinc absorption. We previously reported that soyasaponin Bb has the potential to improve zinc nutrition, because it has the activity to increase mouse ZIP4 expression. Here, we investigated whether soyasaponin Bb increases human ZIP4 expression in several studies. Moreover, we examined ZIP4 expression property during zinc deficiency in rat small intestine, and found that ZIP4 accumulation is more rapid in response to zinc deficiency than previously thought, which suggest that components such as soyasaponin Bb have the efficacy to increase zinc absorption rate by targeting ZIP4 in the small intestine. One of significant roles of zinc is that it is required for the proper brain functions. The mammalian brain contains a significant amount of zinc, with 5-15% concentrated in synaptic vesicles of glutamatergic neurons. Synaptic zinc signaling is involved in synaptic plasticity such as long-term potentiaion (LTP), and memory, in which ZnT zinc transporters probably play significant roles. Therefore, we here established the system to screen soybean component using the genetically engineered cells, which stably expressing ZnT3, ZnT1 or ZnT10, respectively. Each cell enabled us to evaluate their zinc transport activity without directly measuring zinc mobilization across the membranes. These studies facilitate our understanding in preventing zinc deficiency and possibly in improving brain functions.
Soy Protein Research, Japan 19, 1-6, 2016.

Key words : ZIP4, zinc absorption, soyasaponin Bb, brain function, memory, ZnT transporters

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37-2

Effects of Dietary Soy Protein and Whey Protein on Denervation-induced Skeletal Muscle Atrophy

Takeshi NIKAWA*1, Erika TAKATSU1, Marina TAKAGI1, Natsumi YOKOYAMA1, Ayaka TETSUNO1, Hikaru KISHIMOTO1, Kurumi IDA1, Reiko NAKAO2, Hiroaki YANAGAWA3 and Koichi SAIRYO4

1Department of Nutritional Physiology, Graduate School of Biomedical Sciences, Tokushima University, Tokushima 770-8503
2National Institute of Advanced Industrial Science and Techonology (AIST), Tsukuba 305-8561
3Clinical Trial Center for Developmental Therapeutics, Tokushima University Hospital, Tokushima 770-8503
4Department of Orthopedics, Graduate School of Biomedical Sciences, Tokushima University, Tokushima 770-8503

ABSTRACT
We examined whether various diet proteins, including soy protein, whey protein or soy protein plus whey protein, affected denervation-mediated muscle atrophy. Sixweek-old C57/BL6J male mice consumed 20% protein diets that contained casein, soy protein, or soy protein plus whey protein (1:1) for 2 weeks. One hind limb of mouse was enervated on Day 0. Hind limb skeletal muscles were dissected and weighed on Day 4 or Day6. Protein and transcripts expressed in these muscles were analyzed. Denervation caused reductions in mouse gastrocnemius muscle wet weights. On Day 4, this effect was significantly prevented by feeding soy protein or soy protein plus whey protein, whereas the preventive effect of whey protein diet was weak, compared to the casein diet. On Day 6, there was no significant difference in denervation-mediated muscle atrophy among tested protein diets. Soy protein and soy protein plus whey protein prevented the denervation-mediated decrease in IRS-1 level in gastrocnemius muscle on Day 4, while soy protein plus whey protein failed to inhibit dephosphorylation (inactivation) of Akt caused by denervation. Whey protein failed to increase the levels of IRS-1 and phosphorylated Akt, compared with casein protein. Finally, dnervation up regulated the expression of muscle atrophy-related genes, such as MAFbx/atrogin-1, MuRF-1 and Cbl-b. In the gastrocnemius muscle, the soy plus whey protein diet significantly suppressed the upregulated expression of MAFbx/atrogin-1 on Day 6, while the expression of MuRF-1 and Cbl-b was not affected by the tested diets. The present study showed that soy protein plus whey protein (1:1) was most effective in preventing denervation-mediated muscle atrophy.
Soy Protein Research, Japan 19, 7-14, 2016.

Key words : denervation, mice, muscle atrophy, soy protein, whey protein

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37-3

Disease Control of Rust Pathogen in Soybean Using Isoflavone

Yasuhiro ISHIGA*1, Srinivasa R UPPALAPATI2 and Kirankumar S MYSORE2

1Faculty of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8572
2The Samuel Roberts Noble Foundation Inc., Plant Biology Division, Ardmore, Oklahoma 73401

ABSTRACT
Asian soybean rust (ASR) caused by Phakopsora pachyrhizi is a devastating foliar disease affecting soybean production worldwide. Identification of genes that confer nonhost resistance against ASR in another legume species will provide an avenue to engineer soybean to confer durable and broad spectrum resistance against ASR. To this end, we found that Medicago truncatula , a model legume, shows nonhost resistance to P. pachyrhizi and developed a M. truncatula-ASR pathosystem to study nonhost resistance. Although the urediniospores formed germ-tube with appresorium and penetrated into epidermal cells, P. pachyrhizi failed to sporulate on M. truncatula. To investigate the molecular mechanisms of nonhost resistance of M. truncatula against ASR, we performed integrated transcriptome and metabolome analyses. Transcriptome analysis revealed the induction of phenylpropanoid, flavonoid and isoflavonoid metabolic pathway genes involved in the production of phytoalexin medicarpin in M. truncatula upon infection with P. pachyrhizi. Consistent with transcriptome analysis, metabolome analysis also revealed the accumulation of medicarpin and its intermediate metabolites. In addition, the formation of pre-penetration structures including germ-tubes and appresoria was significantly suppressed by treatment with medicarpin. These results clearly indicate that phytoalexin medicarpin plays an important role in nonhost resistance of M. truncatula against P. pachyrhizi.
Soy Protein Research, Japan 19, 15-18, 2016.


Key words : Asian soybean rust, Medicago truncatula , phytoalexin, transcriptome, metabolome

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37-4

Analysis of Plant Parasitic Nematode Infection Steps and Nematode Attractant.

Chie SHIMAOKA, Reila SUZUKI, Morihiro OOTA and Shinichiro SAWA*

Graduate school of Science and Technology, Kumamoto University, Kumamoto 860-8555

ABSTRACT
Because of its agricultural importance, the soybean cyst nematode Heterodera glycines that infects soybean (Glycine max) and Meloidogyne incognita that infect many crops have emerged as good research models to understand the signaling, perception, and response events during plant-nematode interactions. The recent advances in our understanding of the cellular, physiological, and molecular basis of legume-nematode interactions are merging at the crossroads of plant-microbe interactions and plant developmental biology. In order to increase knowledge of molecular mechanisms underlying plant-animal interaction, we have conducted mutant screening showing nematode resistance phenotype using model plant, Arabidopsis thaliana. Plant attraction of plant parasitic nematodes are thought to recognize soluble chemicals in order to find where the plant is. Here, we have found many nematode resistant mutants. They showed various resistance levels. Some of the causal genes would function in the same signaling pathway, and some of them would function in different pathways. In combination with these mutants, we could generate super nematode resistant mutants. This information can be utilized for the defense against nematode damage in an agricultural field. Furthermore, we have purify plant attractants of nematode. By using root extract of kidney beans, we have identified nematode attractant activity by using the PF127 gel assay system. By using this material, we could purify and identify the attractant in a future. These results would contribute basic science on the interaction between multicellular animals and plants. Further, our attractant may be applied to agriculture to reduce economic loss caused by plant parasitic nematode.
Soy Protein Research, Japan 19, 19-23, 2016.


Key words : nematode, Arabidopsis, nematode resistant, attractant, M. incognita

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37-5

Analysis of Genetic Factors Associated with the Contents of Soybean Seed Components in a Controlled Environment

Masao ISHIMOTO*1,a, Yuko YOKOTA1,a, Kyoko TAKAGI2,b and Akito KAGA1,c

1National Institute of Agrobiological Sciences, Tsukuba 305-8602
2NARO (National Agriculture and Food Research Organization) Agricultural Research Center, Tsukuba 305-8666

Present affiliations
aInstitute of Crop Science, NARO, Tsukuba 305-8518
bTohoku Agricutural Research Center, NARO, Fukushima 960-2156
cGenetic Resources Center, NARO, Tsukuba 305-8602

ABSTRACT
Contents of seed components are significant targets in soybean breeding. Soybean seeds comprise ∼40% protein and ∼20% oil, and are rich in minerals such as potassium, calcium, iron, zinc. The content of these seed components is affected by cultivation environments including the climate and the soil, therefore little is known of the genetic control of these traits. In this study, we created a controlled environment by the combination of a LED light source and a hydroponic culture for the genetic analysis of these traits. We cultivated soybean mini-core collections representing large genetic diversity under the controlled environment conditions. After we finish to analyzing the concentrations of seed components in all the varieties of the mini-core collections, we will undertake association mapping to detect quantitative trait loci.
Soy Protein Research, Japan 19, 24-29, 2016.


Key words : association mapping, core collection, elemental analysis, hydroponic culture, light-emitting diode (LED), plant factory

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37-6

Genetic Basis of the Sweet Taste in Edamame Cultivars, Dadachamame, for Improving the Eating Quality

Chiho KAMIMURA, Kana TAKIGUCHI, Tamae KAWAKAMI, Masakazu HATA, Nobushige IIJIMA and Tomoki HOSHINO*

Department of Food, Life, and Environmental Sciences, Faculty of Agriculture, Yamagata University, Tsuruoka 997-8555

ABSTRACT
Dadachamame is a common name for the edamame cultivars 'Shirayama', 'Kanro', and 'Oura'. These cultivars were established in Yamagata Prefecture, northern Japan, in the late Edo era. Dadachamame has an attractive sweet taste and special aroma. Comparison of chemical components in seeds of Dadachamame and other soybean cultivars has shown that the sweet taste of Dadachamame is caused by higher sucrose levels, but the genetic determinants of this difference are unclear. In this study, we obtained 4,836 F2 seeds derived from crosses between three Dadachamame cultivars and the soybean cultivar 'Enrei'. To genotype the F2 plants, we searched for DNA markers with genetic polymorphisms between Dadachamame cultivars and 'Enrei'. We investigated 672 simple sequence repeat (SSR) regions and detected 247 polymorphisms. During early development, 'Shirayama' seeds accumulated twice as much sucrose as 'Enrei' seeds. This result suggests that the high accumulation of sucrose in 'Shirayama' seeds is clearly under genetic control. Using the F2 plants and SSR markers developed in this study, we intend to identify quantitative trait loci (QTL) that control high accumulation of sucrose in Dadachamame seeds. We will discuss the mechanisms of sugar metabolism in Dadachamame seeds that could be used in future studies for improving the eating quality of edamame.
Soy Protein Research, Japan 19, 30-34, 2016.


Key words : Dadachamame, sucrose, sweet taste, genetic approach, quantitative trait loci

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37-7

Development of Preparation Methods for Baked Confectionary Using Soybean Protein Isolate Emulsion

Kazuko HIRAO*, Nobuko EGI, Saori MITSUBOSHI and Kyoko SAIO

Aikoku Gakuen Junior College, Tokyo 133-8585

ABSTRACT
In a previous study, the preparation method of emulsion using soybean protein isolate (SPI), soybean oil, vinegar and water was examined and the optimal mixing ratios were investigated. A dressing type emulsion-based sauce was made, and through addition of white flour and baking powder to the emulsion, its use in baked foods was examined and cakes were produced. In this study, the mixing ratios of the emulsion in baked cakes and its effects when using different varieties and amounts of sugar, white flour and oil were examined. It was found that, similar to flour, the baking powder affected the structure of the cake and contributed to its puffiness. When the baking powder accounted for approximately 3% of total ingredients, puffiness and taste improved. Even though dough amounts were the same sugar variations affected cake expansion. As the amount of added sugar increased the surface of the cake became smoother and softer. Appropriate usage of oil was found to give the cake a rich flavor and moist texture, with margarine or butter being favored. For rice flour, when the amount of sugar added was reduced and coconut oil was used, a puffy cake with a favorable taste was made.
Soy Protein Research, Japan 19, 35-43, 2016.


Key words : SPI, emulsion, baked cakes, sugar, physical properties, sensory evaluation

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37-8

Development of New Gluten-Free Rice Flour Bread Using Foaming Property of Soy Protein

Eiko ARAI*

Laboratory of Cookery Science, School of Food and Nutritional Sciences, University of Shizuoka, Shizuoka 422-8526

ABSTRACT
The use of soymilk instead of water when making gluten-free rice flour bread significantly increases the batter volume after yeast fermentation. Batter made with soymilk rises better during baking than does batter made with water. Glycinin and β-conglycinin contained in soymilk prevent gas cells from merging or collapsing during yeast fermentation and baking. However, when baking bread into a loaf instead of a muffin, gas cells at the center of the crust, where thermal conduction is lowest, collect to form a hollow in the loaf. Adding more than 1.25% of ovalbumin (OVA) to the rice flour prevented formation of this hollow. In addition, OVA levels greater than 2.5% helped the bread rise further through oven spring. These improvements resulted from an increase in thermal coagulation of gas cell membranes and an increase in batter viscosity due to interactions between soy globulins and OVA that promoted starch granule aggregation. Thus, even though OVA levels greater than 2.5% increased the specific loaf volume, they also made the crust harder. As a result, the optimum OVA level is 1.25% of the rice flour. In order to cope with egg allergy, the addition of hydroxypropyl methylcellulose (HPMC) and methylcellulose (MC) as a component to replace OVA was effective.
Soy Protein Research, Japan 19, 44-49, 2016.


Key words : gluten-free, rice flour bread, soymilk, glycinin, ovalbumin

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37-9

Availability of Soybean Resistant Protein Derived from Frozen Soybean Curd for Manifesting Specific Groups of Animal Intestinal Microorganisms

Yutaka UYENO*1 and Takahiro ISHIGURO2

1Academic Assembly (Institute of Agriculture), Shinshu University, Kamiina 399-4598
2Research Institute, Asahimatsu Foods Co, Ltd, Iida 399-2561

ABSTRACT
We carried out in vitro culture trials to investigate the availability of soybean resistant protein (SRP) derived from the frozen soybean curd for manifesting specific groups of animal intestinal microorganisms and examined further use of indigestible carbohydrate combined with SRP. To prepare SRPs, commercially available isolated soybean protein (referred to as NSRP), freeze-denatured soy protein (DSRP), and frozen soybean curd (FSRP) were subjected to enzymatic digestion and processing and hydrochloric acid treatment. Suspended SRP in sterile liquid medium was placed in vials and sealed after gas replacement, then a dilution of the mouse colonic contents was inoculated followed by incubation at 37℃. When the resulted that compared with the control (culture without SRP), the gas generation and volatile fatty acid (VFA) production decreased in the SRP addition groups, suggesting the suppression of anaerobic fermentation. Whereas the total number of bacteria significantly reduced in the SRP groups compared with the control group, ammonia nitrogen concentration in the SRP groups decreased, which suggested changes in the pattern of nitrogen utilization by the intestinal bacteria. In particular, among the SRPs, FSRP showed significant reduction in ammonia nitrogen concentration in comparison with the other two, and the total VFA amount increased. This result may be due to either the indigestible component other than soy protein or the increased SRP portion derived from frozen soybean curd. In the culture with the addition of SRP and indigestible carbohydrates (agar or pectin), an increase in the number of bacteria and total VFA production was observed. Avoiding reduction of bacterial activity by SRP supplementation may be possible by combination use of carbohydrate sources, whereas the suitability of carbohydrate sources to be combined with SRP will warrant the need for further study.
Soy Protein Research, Japan 19, 50-54, 2016.


Key words : Frozen soybean curd, Intestinal microbial community, Prebiotics, Soybean resistant protein

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37-10

Study of Stabilization Mechanism of Nano Scale Emulsion by Soy Protein Component Using Gradient NMR

Shingo MATSUKAWA*

Department of Food Science and Technology, Graduate School of Marine Science and Technology, Tokyo University of Marine Science and Technology, Tokyo 108-8477

ABSTRACT
Thermal stabilities of nano size emulsion stabilized by soy proteins were studied by measuring size distributions and NMR. It has been found that egg lecithin was more effective than soy lecithin in making smaller size emulsion but allowed coagulation under heating. Addition of soy protein to the egg lecithin inhibited the formation of the nano size emulsion but gave the thermal stability to the emulsion. 1H NMR and 31P NMR measurements suggested that protein exists as suspension of aggregates and they have no interaction with lecithin on the emulation surface.
Soy Protein Research, Japan 19, 55-58, 2016.


Key words : impinging jet homogenizer, nano emulsion, soy protein, gradient NMR

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37-11

Denaturalized Soluble Protein in High Pressure and Hydrothermal Conditions and Evaluation of its Function

Masaru WATANABE*

Research Center of Supercritical Fluid Technology, Graduate School of Engineering, Tohoku University, Sendai 980-8579

ABSTRACT
Denaturalized soluble protein (DSP), or hydrothermal soluble protein (HSP) was prepared in high pressure and hydrothermal condition and its function (foaming property, antioxidant activity and hypotensive effect) was evaluated. To enhance the yield of DSP, a base additive was effective. The maximum yield of DSP at 190℃ in the presence of base additive for 1 hour was 80% based on the original amount of protein in defatted soybean. The peak of molecular weight distribution of DSP by GPC was around 10 kDa. For foaming ability, foaming capacity and forming stability of DSP were higher than those of alkali soluble (60℃, 30 min, pH 8 NaOH solution) soybean protein. The antioxidant activity (AA%) of DSP was evaluated by the DPPH method. The AA% of DSP was 63% and that of SPI, which is commercially available soluble protein isolate (SPI), was 64%. AA% is closely related to the order of amino acid polymerized (such as histidine, proline and hydrophobic amino acid) and thus DSP probably consists of histidine and proline in the structure. Hypotensive effect of DSP was also measured by ACE inhibition effect. That is, blood pressure is raised by the activity of angiotensin converting enzyme (ACE) and IC50 [mg/L], which is a concentration of 50% inhibition of ACE, was evaluated. As a result, while IC50 of SPI was 3.3 mg/L, that of DSP was only 0.66 mg/L and thus DSP is superior to SPI in view of its hypertensive effect. For hypertensive effect, C-terminus amino acid in a peptide is related and proline, lysine, phenylalanine, tyrosine and aginine are attached at the C-terminus of DSP. In the DSP, the C-terminus was increased by hydrolysis under hydrothermal condition and thus we consider that IC50 of DSP was remarkable.
Soy Protein Research, Japan 19, 59-63, 2016.


Key words : high pressure process (HPP), hydrothermal technology solubility, soy peptide, functional peptide

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37-12

Establishment of a System Biology Analysis Using Flavonoid as a Lead Compound

Seiji MASUDA*

Laboratory of Molecular Biology of Bioresponse, Graduate School of Biostudies, Kyoto University, Kyoto 606-8502

ABSTRACT
The processing of mRNA is an essential step for gene expression in humans. In the previous study, I found that apigenin, a kind of flavonoid, has an inhibitor activity for mRNA processing. Further analysis indicates that the mechanism of its inhibition is assumed to be in the mRNA splicing step, because it is strongly associated with many of U2 snRNP components, an essential mechanism to determine the 3' acceptor site for mRNA splicing. These results suggest that apigenin inhibits mRNA splicing through the interaction with U2 snRNP and its related factors like U2AF. In the present study, I have examined to obtain the reference gene index for the establishment of a system biology analysis method using a test compound of food origin. As a test compound, I have used apigenin because its action is achieved through the interaction with U2 snRNP and it inhibits the mRNA splicing. Apigenin was added to a cell culture and the change in mRNA splicing was examined. Apigenin changed the mRNA splicing in several genes but did not change the mRNA splicing in other genes, indicating that apigenin affects a specific mRNA splicing set but not all mRNA splicing. From this analysis, I concluded that I have obtained a good reference gene index. Using this index, I would like to analyze the global effect on apigenin on mRNA splicing.
Soy Protein Research, Japan 19, 64-68, 2016.


Key words : system biology, flavonoid, mRNA processing

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37-13

Comparison of Effects on Hepatic Glucose and Lipid Metabolism of Soy Protein Isolate and Mung Bean Protein Isolate.

Hiroshi INOUE*

Metabolism and Nutrition Research Unit, Innovative Integrated Bio-Research Core, Institute for Frontier Science Initiative, Kanazawa University, Kanazawa 920-8641

ABSTRACT
Non-alcoholic fatty liver disease (NAFLD) encompasses a spectrum of liver diseases involving hepatocyte dysfunction due to triglyceride accumulation in these cells. It has become a common disease affecting 20-30% of the Asian, European and U.S. populations. Some cases of non-alcoholic fatty liver (NAFL) are known to progress into non-alcoholic steatohepatitis (NASH), which involves inflammation and fibrosis, and eventually leads to cirrhosis. This has prompted the development of strategies for NAFLD prevention and treatment, including dietetics approaches. In this study, we found mung bean protein isolate (MPI) to be an alimentary protein ameliorating hepatic steatosis. We have investigated the effects of MPI on hepatic glucose and lipid metabolism by feeding mice a normal or a high-fat diet containing casein, MPI, or Soy Protein Isolate (SPI) as a source of alimentary protein for 4 weeks. Although there was no difference among the effects of casein, MPI and SPI on body weight and insulin sensitivity in mice feeding experiments, MPI suppressed the expression of de novo lipogenesis-related genes in the liver and decreased hepatic triglyceride content under both normal- and high-fat dietary conditions more potently than casein or SPI. Although the mechanism of how MPI reduces hepatic triglyceride content remains unclear, MPI may be a potential preventive foodstuff for NAFLD.
Soy Protein Research, Japan 19, 69-73, 2016.


Key words : NAFLD, mung bean protein isolate, SPI, lipogenesis

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37-14

Stimulation of Natural Killer Activity by a Soy Peptide

Masaya NAGAO*

Laboratory of Biosignals and Response, Graduate School of Biostudies, Kyoto University, Kyoto 606-8502

ABSTRACT
Peptides derived from food proteins have various biological functions. In this study, a peptide derived from soy glycinin G4 subunit was examined for its potential for stimulating the tumoricidal activity of natural killer cells. This peptide directly stimulated the tumoricidal activity of KHYG-1 natural killer (NK) leukemia cells against K562 human chronic myeloid leukemia cells. Production of interleukin-12, an activator of NK cells, from THP-1-derived human dendritic cells was not enhanced by this peptide.
Soy Protein Research, Japan 19, 74-77, 2016.


Key words : soy peptide, innate immune system, natural killer cells

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37-15

Comprehensive Analysis to Identify Soy Peptides with Inhibitory Effects for Human Dipeptidyl Peptidase IV

Keisuke ITO*

School of Food and Nutritional Sciences, University of Shizuoka, Shizuoka 422-8526

ABSTRACT
Human dipeptidyl peptidase IV (hDPPIV) is an important target for the treatment of type 2 diabetes. Food components able to modulate hDPPIV activity have attracted attention from a preventive perspective. In this study, we present a comprehensive analysis of a set of 337 dipeptides with respect to their hDPPIV inhibitory effects. In addition to the fact that dipeptides are generated in a large quantity from dietary proteins, many previous studies have strongly suggested that dipeptides are the practical core units of hDPPIV inhibitory peptides. Dipeptides were ranked in the order of their hDPPIV inhibition intensities. The particularly highly inhibitory dipeptides, Phe-Ala, Leu-Ala, Ile-Ala, and Met-Leu, etc., were found in a soy protein hydrolyzate. These dipeptides, generated in a large quantity by hydrolysis, are prime candidates contributing to the hDPPIV inhibitory effect of the soy protein hydrolyzate. We also report a novel soy tripeptide, Trp-Arg-Glu, that noncompetitively inhibits hDPPIV. Trp-Arg-Glu tripeptide showed the synergistic inhibition with Gly-Pro-Ala contained in a collagen hydrolysate. The molecular mechanism of the synergistic eff ect was also discussed by the structural modeling of hDPPIV-inhibitor complex.
Soy Protein Research, Japan 19, 78-83, 2016.


Key words : human dipeptidyl peptidase IV, inhibitor, dipeptides, tripeptides

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37-16

Antimicrobial Activity and Mechanism of Action of Peptides Derived from Soy Proteins

Masayuki TANIGUCHI*

Department of Materials Science and Technology, Faculty of Engineering Niigata University, Niigata 950-2181

ABSTRACT
Food proteins provide organisms with the amino acids necessary for the maintenance of life. Recently, another function of food proteins has become well known; they are a source of antimicrobial peptides (AMPs). These peptides are inactive within the sequence of the parent protein and must be released during gastrointestinal digestion, fermentation, or food processing. AMPs can be generated from proteins of different food origins, including soybean, milk, egg white, and wheat. In this study, we selected natto (fermented soybean) as a source of AMPs. We prepared fractions with cationic peptides from a natto extract by autofocusing. The antimicrobial activity of the cationic peptide fractions against human pathogens was quantitatively evaluated using a chemiluminescence method that measures ATP derived from viable cells. The cationic peptide fractions exhibited antimicrobial activity against Porphyromonas gingivalis (a periodontal diseaseassociated bacterium) and Propionibacterium acnes (an acne-related Gram-positive bacterium), but not against Candida albicans (an opportunistic fungal pathogen). After we purified the peptides in cationic fractions with antimicrobial activity by reversed phase chromatography, the peptides were identified by matrix-assisted laser/desorption ionization-time-of-flight mass spectroscopy (MALDI-TOF MS). Of 88 types of peptides identified, we chemically synthesized 12 types of peptides with high isoelectric points and positive net charges. Of 12 types of peptides synthesized, the several peptides exhibited antimicrobial activity against human pathogens including C. albicans and Streptococcus mutans (a dental caries-associated bacterium).
Soy Protein Research, Japan 19, 84-88, 2016.


Key words : cationic peptide, soy bean protein, antimicrobial activity, mechanism of action, human pathogen.

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37-17

Study of Mechanism of Feeding Regulation Triggered by Gastric Vagal Nerve Outflow Suppressed by Soy Isoflavone

Mamoru TANIDA*

Department of Physiology 2, School of Medicine Kanazawa Medical University, Uchinada, Ishikawa, 920-0293

ABSTRACT
Previously, we found that isoflavone decreased vagal nerve activity supplying the stomach, and reduced body weight gain and food intake of rats fed a normal diet. In the study presented here, to examine the possible role of suppressed vagal nerve signal innervating the stomach in isoflavone-induced appetite reduction, the present study used rats and investigated the Effects of isoflavone injection on central and peripheral peptides levels which relate with vagal nerve signals. Intragastric (IG) injection of isoflavone did not affect hypothalamic expressions of POMC and NPY controlling feeding behavior. On the other hand, IG isoflavone significantly decreased blood ghrelin level 30 min after injection. In addition, isoflavone injection of the anesthetized rats reduced afferent celiac nerve outflow modulating intestinal tissues, but not for the afferent gastric nerve. Thus, these data suggest that isoflavone may arrive in the intestine and affect the afferent nerve to send the signals to the brain, resulting in decreased efferent gastric vagal outflow and ghrelin level through the gut-brain pathway to regulate appetite and body weight.
Soy Protein Research, Japan 19, 89-95, 2016.


Key words : Hypothalamus, autonomic nerves, ghrelin, afferent sympathetic nerve branch, appetite

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37-18

Chemo-preventive Effects of Daidzein and Its Related Compounds on Estrogen-dependent Breast Cancer

Yoshinori OKAMOTO*

Laboratory of Hygienic Chemistry, Faculty of Pharmacy, Meijo University, Nagoya 468-8503

ABSTRACT
Estrogen is an endogenous hormone, but it is known to induce breast, uterine and ovary cancers. In addition, estrogen and its related drugs, prescribed for postmenopausal women, also induce cancers in the reproductive organs. Much research has been conducted to prove genistein's chemo-preventive effect on mammary tumors; however, its effect remains unclear. Our recent study showed that daidzein, not genistein, is a key molecule for anti-tumor effect. Therefore, daidzein might prevent mammary tumor formation and contribute to the improvement of women's health. The aim of this study is to determine the chemo-preventive effect of daidzein, one of the major soy isoflavones, and its related compounds on estrogeninduced mammary tumors using an estrogen-induced mammary tumor model, the August Copenhagen-Irish/Segaloff (ACI/Seg) rat.
Soy Protein Research, Japan 19, 96-101, 2016.


Key words : breast cancer, soy isoflavones, chemo-prevention, ACI/Seg rat, LC/MS/MS analysis.

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37-19

The Inhibitory Effect of Soybean Isoflavone Diets on Dinitrofluorobenzene-Induced Contact Hypersensitivity in Mice

Takao NAGANO*

Department of Clinical Nutrition, Faculty of Health Science and Technology, Kawasaki University of Medical Welfare, Kurashiki 701-0193

ABSTRACT
Murine contact hypersensitivity (CHS) is one of the most frequently used animal models of human allergic contact dermatitis. In the present study, we investigated the inhibitory effects of soybean and soy isoflavone (SI) diets on 2,4-dinitrofluorobenzene-(DNFB) induced CHS in mice. The DNFB-induced ear swelling was inhibited in the soy- and SI-treated groups. Histopathological investigations revealed that oral feeding of soybean and SI reduced the number of Gr-1+ cell infiltrations into ear tissues. DNA microarray analysis showed that the expression of Ccl24, Xcl1, Ifng, and Ccl17 in the ear tissues was lower in the soy-treated mice than in the positive controls. In addition, chemokine (C-C motif) ligand 24 (CCL24) mRNA and protein expression in the ear tissues were more highly suppressed in the soy- and SI-treated groups. These results suggest that SI consumption downregulated the gene and protein expression of CCL24, thereby affording protection against CHS in mice.
Soy Protein Research, Japan 19, 102-106, 2016.


Key words : soybean, isoflavones, dinitrofluorobenzene, contact hypersensitivity, chemokine (C-C motif) ligand 24

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37-20

Comparative Activities of Equol Enantiomers on Bone Metabolism.

Mariko UEHARA*, Shungo FUJII, Hirofumi INOUE, Rie KATSUMATA-TSUBOI and Nobuyuki TAKAHASHI

Laboratory of Physiology and Metabolism, Department of Nutritional Science and Food Safety, Faculty of Applied Bioscience, Tokyo University of Agriculture, Tokyo 156-8502

ABSTRACT
Soy isoflavones and their metabolites, have shown promising therapeutic application for osteoporosis. The recent clinical efficacy of soy isoflavones in humans may be attributed to their ability to produce equol, a metabolite of daidzein, in the intestinal tract. The equol producers may have benefi cial effects for the prevention of hormone-related cancers, cardiovascular diseases, and osteoporosis. Equol is a chiral molecule that exists as the enantiomers (S)(-)-equol and (R)(+)-equol. Although both equol enantiomers have higher affinity for estrogen receptors (ERs) than the biosynthetic precursor daidzein, the ER affinity and transcriptional activity may differ between equol enantiomers. To compare the effect of (R)-equol and (S)-equol on osteoclastogenesis and bone fragility, bone marrow cells (BMCs), RAW264.7 cells and ovariectomized (OVX) mice were used. Mouse BMCs or RAW264.7 cells were treated with equol enantiomers (0.1-10µM) in the presence of vitamin D3 or RANKL, an osteoclastogenesis inducer. After 6 days of treatment, the cells were stained for tartrate-resistant acid phosphatase (TRAP), a maker of osteoclast differentiation. Furthermore, osteoclastogenesis-related gene expression was evaluated. Ovariectomized (OVX) animal (a model of postmenopausal osteoporosis) experiment was also performed using several doses of equol enantiomers. The equol enantiomers inhibited osteoclastogenesis. (R)-equol had stronger effects than (S)-equol in BMCs, but not in RAW264.7 cells. As natural selective estrogen receptor modulators (SERMs), (S)-equol improved bone loss due to OVX, while minimizing the impact on the uterus. Since concentrations of (S)-equol were clearly increased in serum and tibia compared to those of (R)-equol, the inhibitory activity on bone loss was stronger in (S)-equol than in (R)-equol. The details of difference between both equol enantiomers should be clarified in further studies.
Soy Protein Research, Japan 19, 107-114, 2016.


Key words : (S)(-)-equol, (R)(+)-equol, osteoclastogenesis, ovariectomized mice, osteoporosis

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37-21

The Effects of β-conglycinin on the Dysfunction of Lipid Metabolism in Cbl-b-deficient Mice

Tomoki ABE*, Takayuki UCHIDA, Chisato TOMIDA, Ayako MAITA, Shigetada KONDO and Takeshi NIKAWA

Department of Nutritional Physiology, Institute of Biomedical Sciences, Tokushima University, Tokushima, 770-8503

ABSTRACT
It is known that β-conglycinin prevented high-fat diet (HFD)-induced fatty liver in rodents. β-Conglycinin suppress absorption of dietary lipids in the intestine and expressions of lipogenic genes in liver. Recently, we demonstrated that the deficiency of Casitas B lineage lymphoma-b (Cbl-b) enhanced obesity, insulin resistance and fatty liver induced by HFD in mice. In this study, we aimed to elucidate mechanisms for improvement of fatty liver by dietary β-conglycinin in Cbl-b-deficient (Cbl-b-/-) mice. The dietary β-conglycinin completely suppressed Cbl-b deficiency-enhanced body weight gain and fatty liver in mice fed HFD. We observed increased expression of stearoyl-CoA desaturase 1 (Scd1) in Cbl-b-/- mice fed casein-containing HFD. In contrast, β-conglycinin-containing HFD decreased expression of Scd1 in liver from Cbl-b-/- mice. We also found dietary β-conglycinin induced fibroblast growth factor 21 (Fgf21) expression in liver from mice. Interestingly, depletion of Cbl-b promoted β-conglycinin-induced expression of Fgf21. These results indicate that dietary β-conglycinin suppresses Cbl-b deficiencyenhanced fatty liver as well as HFD-induced fatty liver in mice. However, further study is necessary to elucidate role of Cbl-b in β-conglycinin-induced expression of Fgf21.
Soy Protein Research, Japan 19, 115-120, 2016.


Key words : β-conglycinin, Cbl-b, fatty liver, high-fat diet

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37-22

Effect of Preload of Soy Protein Isolate and Its Peptide on Postprandial Glycemic and Gastric Emptying Responses in Healthy Humans

Hideaki KASHIMA*1, Masaki FUJIMOTO1, Masako ENDO (YAMAOKA)1, Akira MIURA1, Toshio KOBAYASHI2 and Yoshiyuki FUKUBA1

1Department of Exercise Science and Physiology, School of Health Sciences, Prefectural University of Hiroshima, Hiroshima 734-8558
2Department of Health Promotion and Development, Graduate School of Health Sciences, Hiroshima University, Hiroshima 734-8551

ABSTRACT
The study aim was to examine the effect of consuming a soy protein isolate (SPI) and its peptide (PEP) before a 75-g oral glucose tolerance test (OGTT) on subsequent glycemic control. After overnight fasting, nine healthy young subjects consumed a 200-mL liquid containing either 20 g of SPI or PEP. Thirty minutes after those consumption, an OGTT was performed to evaluate the individual glycemic response. Blood glucose and plasma insulin concentrations were measured immediately before the either the SPI or the PEP preload (i.e., 30 min before the start of the OGTT), and before (-5 min) and during the OGTT (15, 30, 45, 60, 90 and 120 min). The gastric emptying rate was evaluated by 13C breath test. Breath samples were collected at 5-15 min intervals for 4 h. Insulin secretion was significantly higher for PEP than that for SPI before oral glucose consumption. The blood glucose response was significantly less for PEP than that for SPI at 15 min after oral glucose consumption. However, the incremental area under the curve and peak blood glucose response were not significant different between treatments. The gastric emptying rate showed a tendency to be faster for PEP than that for SPI. Although the SPI and PEP preloads effect on the postprandial hyperglycemic response are comparable, the insulin and gastric emptying responses to these preloads are different.
Soy Protein Research, Japan 18, 129-137, 2015.


Key words : soy protein isolate, soy peptide, insulin, gastric emptying, glycemic control

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37-23

Reducing Effects of Oxidative Stress Using Soy Yogurt

Hideki KINOSHITA*1, Momoka SHOJI2, Hiroki HOSHIGAMI2 and Kohei WATANABE2

1Laboratory of Food Biochemistry, Department of Bioscience, School of Agriculture, Tokai University, Kumamoto 862-8652
2Laboratory of Microbial Functional Health Science, Department of Food Management, School of Food, Agricultural and Environmental Sciences, Miyagi University, Miyagi 982-0215

ABSTRACT
Reactive oxygen species (ROS), such as hydroxyl and superoxide anion radicals, are highly reactive molecules derived from the metabolism of oxygen. ROS play positive roles in cell physiology, but they may also damage cell membranes and DNA, inducing oxidation that causes membrane lipid peroxidation and decreased membrane fluidity. Fermented soy milk (soy yogurt) using lactic acid bacteria (LAB) is a good food that has many functional substances containing antioxidants. In this study, the antioxidative activities of soy yogurt were investigated. The LAB strains which solidified soy milk were 16 strains out of 26 strains. The supernatant of soy yogurt made from Lactobacillus gasseri MYU1 showed the highest ORAC and HORAC values. Leuconostoc mesenteroides MYU60 and Pediococcus pentosaceus MYU759 showed the highest values in ORAC and HORAC tests, respectively. Leu. mesenteroides MYU60, Lb. plantarum MYU74, Lb. reuteri MYU220, and P. pentosaceus MYU759 showed significantly high N-acetylcysteine equivalent compared with a control in total ROS reducing assay (p<0.05). These strains were selected and the comet assay were performed. The comet value was decreased in all selected strains compared with a control meaning that there was a DNA protection effect. Finally, the exopolysaccharide (EPS) of the supernatants were purified and quantitated. The results show Lb. reuteri MYU220 and P. pentosaceus MYU759 produce both natural and acidic EPS. P. pentosaceus MYU759 is an especially high-EPS producer. These results suggest EPS is one of the antioxidants of P. pentosaceus MYU759 and this strain is a good candidate for functional soy yogurt.
Soy Protein Research, Japan 19, 126-131, 2016.


Key words : lactic acid bacteria, antioxidant, soy yogurt, reactive oxygen species, exopolysaccharide

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37-24

Effects of Dietary Protein Types During Pregnancy on Skin Components

Takumi YAMANE*

Laboratory of Molecular Bioregulation, Department of Nutritional Science and Food Safety, Faculty of Applied Bioscience, Tokyo University of Agriculture, Tokyo 156-8502

ABSTRACT
The skin contains large amounts of extracellular matrix components such as hyaluronan, which are produced mainly by fibroblasts and/or keratinocytes and protect the body from various external insults. Hyaluronan retains moisture in the skin, facilitates the transport of ion solutes and nutrients, and promotes wound healing. Although it is well established that maternal protein nutrition is critical for newborn physiology, little information is available on the effects of dietary protein types during pregnancy on hyaluronan metabolism in the skin of newborn mice. In this study, we investigated effects of dietary protein types during pregnancy on hyaluronan synthesis in the skin of newborn mice. Pregnant rats were fed a soy protein isolate-based (a high quality protein) or gluten-based diet (a low quality protein) during gestation for 5 days. The levels of hyaluronan and hyaluronan synthase (Has)2 mRNA were increased in the skin of newborn mice from dams fed gluten diets during pregnancy. However, the skin mRNA expression of KIAA1199, which play a primary role in hyaluronan degradation in the dermis, was decreased. No significant differences in mRNA levels of Has3 and Hyal2 were observed. These results show that low quality protein diets during pregnancy promote hyaluronan synthesis along with increases in Has2 transcript and decreasing KIAA1199 mRNA levels in the skin of newborn mice.
Soy Protein Research, Japan 19, 132-135, 2016.


Key words : newborn, skin, hyaluronan, hyaluronan synthase (Has), KIAA1199

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37-25

The Effect of L-arginine Administration on Exercise-induced Calpain Activation and Force Depression

Keita KANZAKI*1, Daiki WATANABE2, Yuki KAWAKAMI1, Yoshitaka TAKAHASHI1 and Masanobu WADA2

1Faculty of Health and Welfare Science, Okayama Prefectural University, Soja 719-1197
2Graduate School of Integrated Arts and Sciences, Hiroshima University, Higashihiroshima 739-8521

ABSTRACT
In this study, we examined the effects of L-arginine (ARG) administration on calpain activation and force output in rat skeletal muscle exposed to eccentric contractions (EC). Male Wistar rats were allowed ad libitum to drink 0.3% L-ARG solution (221 ± 7 mg/day of L-ARG) 3 days prior to the EC. Age-matched controls (CON) were provided water without L-ARG. After 3 days, the left anterior crural muscles were exposed to 200-repeated EC. The contralateral muscles were used as controls. Three days following EC, isometric torque produced by the anterior crural muscles was measured and then tibialis anterior muscles were removed and used for biochemical analyses. In CON muscles, the increase in total calpain activity and calpain-1 autolysis was observed. L-ARG treatment alleviate increase in calpain activity and abrogate increase in calpain-1 autolysis. In all stimulation frequency, isometric torque in ARG muscles was greater than that in CON muscles, although the decrease in torque evoked by low-frequency (1∼20 Hz) stimulation was also observed in ARG muscles. In addition, L-ARG administration induced the suppressed degradation of dihydropyridine receptor and ryanodine receptor and the attenuated degradation of junctophilin-1. These results suggest that dietary L-ARG supplementation may facilitate force recovery following EC by preventing the calpain-mediated proteolysis of Ca2+- regulatory proteins.
Soy Protein Research, Japan 19, 136-142, 2016.


Key words : L-arginine, eccentric contraction, muscle damage, calpain, proteolysis

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37-26

Effects of Genistein on Prx4 and SOD1 Double Knockout Mouse as an in vivo Model for Exploring Oxidative and ER Stress-induced Hepatic Disorder

Takujiro HOMMA*, Ryusuke AKIHARA, Toshihiro KURAHASHI, Jaeyong LEE and Junichi FUJII

Department of Biochemistry and Molecular Biology, Graduate School of Medical Science, Yamagata University, Yamagata 990-9585

ABSTRACT
Among multiple factors, oxidative stress and endoplasmic reticulum (ER) stress are promising causes for developing steatosis and the progression of non-alcoholic steatohepatitis (NASH). It has been reported that mice deficient for superoxide dismutase 1 (SOD1), a superoxide-detoxifying enzyme, spontaneously develop steatosis. We have previously demonstrated that the coordinate action of oxidative stress and the following ER stress caused by SOD1 deficiency is the underlying mechanism for lipid droplet accumulation in primary cultured hepatocytes. At the same time, peroxiredoxin 4 (Prx4) works on coupling hydrogen peroxide catabolism with oxidative protein folding in ER and hence exerts protection against oxidative stress via elimination of hydrogen peroxide. In fact transgenic overexpression of human Prx4 protects mice against the progression of NASH that is triggered by feeding a methionine- and choline-deficient (MCD) diet. In the current study, we generated Prx4 and SOD1 double knockout (Prx4-/-Sod1-/-) mice and examined whether the combined deletion of Prx4 and SOD1 aggravated NASH compared to single knockout. As results, spontaneous liver damage characterized by caspase-3 activation and plasma ALT elevation was evident in the developing Prx4-/-Sod1-/- mice, which showed increased incidence of premature death before adulthood. The double knockout mice fed with the MCD diet developed hepatic steatosis with a further increase in plasma ALT. Then we explored nutritional factors that might ameliorate NASH using Prx4-/-Sod1-/- mice. The liver damage was markedly attenuated by genistein, a soy isoflavone with antioxidant and anti-inflammatory properties. Thus, Prx4-/-Sod-/- mice will be a useful animal model for studying NASH development and testing other potential treatments.
Soy Protein Research, Japan 19, 143-146, 2016.


Key words : oxidative stress, ER stress, SOD1, Prx4, genistein

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37-27

Search and Evaluation of the Slow-type Muscle-increasing Factors Derived from Soybean

Takaoki SANEYASU*, Haruka SHINDO, Kazuhisa HONDA and Hiroshi KAMISOYAMA

Laboratory of Animal Nutrition and Metabolism, Division of Animal Science, Department of Bioresource Science, Graduate School of Agricultural Science, Kobe University, Kobe 657-8501

ABSTRACT
We previously reported that dietary soybean germ protein significantly increased skeletal muscle weight in meat-type chickens. Furthermore, our unpublished data showed that the hot-water extract fraction of soybean germ (SG-HW) increased skeletal muscle weight in chickens and the leg weight increased at a rate greater than the breast muscle weight. It is known that chicken breast muscle consists almost completely of glycolytic fast-twitch (type IIB) fiber, whereas chicken leg muscle contains oxidative slow-twitch (type I), oxidative fast-twitch (type IIA), and type IIB fiber. These findings raise the possibility that dietary SG-HW preferentially increases oxidative twitch fibers in chickens. We herein investigated the effects of dietary SG-HW on muscle fiber type specific gene expression in chickens and rats. Dietary SG-HW significantly increased the mRNA levels of slow type troponin I and decreased fast type troponin I expression in chicken adductor superficialis muscle, which consists mainly (80%-95%) of type IIA fibers. The mRNA levels of slow type troponin I was tended to be increased by dietary SG-HW in chicken biceps femoris muscle, which consists of IIA (40%-50%) and IIB (50-60%) fibers. In contrast, dietary SG-HW significantly increased the mRNA levels of fast type troponin I in chicken breast (pectoralis major) muscle. No significant difference between the control and the SG-HW group was observed in the mRNA levels of myosin heavy chain isoforms in rat biceps femoris and gastrocnemius muscle. The present findings indicate the possibility that dietary SG-HW preferentially increases slow type fibers in chicken skeletal muscles containing IIA fibers.
Soy Protein Research, Japan 19, 147-152, 2016.


Key words : soybean germ, slow type muscle, myosin heavy chain, chicken, rat

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37-28

Development of Open-sandwich Fluorescence-linked Immunoassay and High Throughput Analysis of Soy Isoflavones

Seiichi SAKAMOTO*

Faculty of Pharmacognosy, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka 812-8582

ABSTRACT
Soy isoflavones are known as major bioactive compounds in soybean (Glycine max), which is an indispensable food. Despite their utility, the consumption of isoflavones has recently been limited because they exhibit oestrogenic and topoisomerase II inhibitory effects. To assess their intake limitation, accurate, sensitive, and effective quantitative analyses are necessary. Previously, we produced the monoclonal antibody (MAb) against daidzin (DZ) and applied it to an indirect competitive enzyme-linked immunosorbent assay (icELISA) for the simultaneous determination of DZ and genistin (GEN), which are known as two major soy isoflavone glycosides in soy products. However, an even more rapid, sensitive and simple analytical method is required for their determination. In this study, we aimed to develop open-sandwich fluorescence-linked immunosorbent assay (OS-FLISA) for their high throughput analysis by taking advantages of enhanced interaction between variable regions of heavy (VH) and light (VL) chains in the presence of antigen. A single-chain variable fragment (scFv) antibody against DZ, which consists of VH and VL domains, was primarily constructed to investigate whether the VH and VL domains retain characteristics of their parental DZ-MAb. As a result, scFv against DZ (DZ-scFv) expressed in silkworm exhibited same characteristics as parental DZ-MAb, which revealed that the VH and VL domains can be used to develop OSFLISA. The VL domain, VH-AcGFP and AcGFP-VH domains were then ligated into pMAL-p5X vector (New England Biolabs) to express them as fusion proteins with maltose binding protein (MBP). Construction, expression, and characterization of DZ-scFv expressed in silkworm larvae, and construction and expression of MBPVL, MBP-VH-AcGFP, and MBP-AcGFP-VH domains expressed in Escherichia coli were described in this report.
Soy Protein Research, Japan 19, 153-159, 2016.


Key words : daidzin (DZ), green fluorescence protein (GFP), monoclonal antibody (MAb), open-sandwich fluorescence-linked immunosorbent assay (OSFLISA), single-chain variable fragment (scFv) antibody

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37-29

The Inhibitory Effects of the Soybean Extract and Isoflavone on the Growth of Monilinia Fructicola and Phomopsis sp.

Takanori SAITO*

Graduate School of Horticulture, Chiba University, Matsudo 271-8510

ABSTRACT
Peach (Prunus persica L. Batsch) fruit is the one of the fruits most susceptible to postharvest diseases, such as brown rot and Phomopsis fruit rots, which are caused by Monilinia fructicola and Phomopsis sp., respectively. In contrast, it is known that the pea species including soybean produce isoflavones, which possessed anti-fungal activity, to defend themselves against fungal attack. Thus, the author investigated the relationship between the concentration of six isoflovenes (daidzin, daidzein, genistin, genistein, glycitin, and glycitein) and the mycelial growth of M. fructicola and Phomopsis sp. Among them, two isoflavones (genistin and genistein) showed a relatively higher inhibitory effect at 10 ppm against the growth of Phomopsis sp. on in vitro assay; however, six isoflavones investigated in this study did not show a inhibitory effect against M. fructicola. It was also investigated that the antifungal effect of soybean extract against Phomopsis sp.; however, soybean extract (∼300 ppm) did not inhibit the growth of Phomopsis sp. Additionally, although the postharvest application of genistin and genistein (10 and 100 ppm) on peach was assessed, neither isoflavone was effective against the growth of Phomopsis sp on the surface of peach fruits.
Soy Protein Research, Japan 19, 160-164, 2016.


Key words : peach, postharvest, Phomopsis fruit rots, anti-fungal activity

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37-30

A Method to Increase in Food Preference for Soybean Products and Frequency of Their Consumption

Tomoko OSERA*

Dietician Training Course, Faculty of Home Economics, Kobe Women's University, Kobe 654-8585

ABSTRACT
Soybean products are healthy and an important source of vegetable protein in Japan. Japanese people, especially children, do not eat soybean very much. This study examines the effects of using soybean products at home in decreasing children's dislike of soybean products. A quasi-experimental pre-post-test design was utilised to examine the effect of using school lunch programs to assess the consumption of soybean products. The first was Intervention, wherein children received school lunch in kindergarten 4 days per week (186 children total); in addition, teachers and nutritionists also provided information about soybeans to children during school meals. The second was Comparison A, wherein children received a lunch box in kindergarten 4 days per week (97 children total). In the third group, Comparison B, children received school lunch in nursery facilities 5 days per week (30 children total). The program SPSS (version 23.0, SPSS, IBM Inc.) was used for statistical analysis of the data. Using Fisher's exact probability test, we compared the score among the 3 groups before and after the intervention. The study's participants included 309 children (mean 4.2 ± 0.8 ages) attending kindergarten and nursery facilities. Children's thinking about 'respect for food' was significantly higher in the intervention groups than the comparison group (p<0.01, p=N.S, p=N.S, by Fisher's exact test). The improvement in knowledge about nutrition education in the intervention group and Comparison A was significantly higher than in the comparison B (p<0.01, p<0.01, p=N.S). Health education involving the soybean program may lead to an increase in thinking about "respect for food" among kindergarten children and an increase in providing knowledge in their guardians.
Soy Protein Research, Japan 19, 165-170, 2016.


Key words : children, soybean products, school lunch

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Soy Protein Research (Japan)