Improving the Surface Functionality of Curdlan by Conjugation with Unfolding Protein through Naturally Occurring Maillard Reaction

Nakamura, Soichiro,Ogawa, Masahiro,Saeki, Hiroki,Saito, Masayoshi,Miyasaka, Satoko,Hata, Junya,Adachi, Naoko,Hwang, Jae-Kwan The Korean Society of Food Science and Nutrition 2000 Preventive Nutrition and Food Science Vol.5 No.4

Protein conjugation of curdlan belonging to $\beta$-1, 3-glucan was carried out to improve it surface functionalities. The glucan was mixed with phosvitin, {TEX}$$\alpha$_{s}${/TEX}-casein, lysozyme or ovalbumin, respectively. The mixture was freeze-dried, and he resulting powder was incubated at 6$0^{\circ}C$ and 79% relative humidity for 12 days in order to generate a controlled Maillard reaction between curdlan and proteins. conjugation with unfolding proteins, i.e., phosvitin and {TEX}$$\alpha$_{s}${/TEX}-casein, drastically increased the solubility of the glucan, whereas lysozyme and ovalbmin did not. The solubility in water of curdlan was 3.44% for the phosvitin conjugate and 1.09% for the {TEX}$$\alpha$_{s}${/TEX}-casein conjugate. SDS-slab polyacrylamide gel electrophoresis showed that curdlan was solubilized due to covalent binding with phosvitin. Emulsifying properties of curdlan were substantially improved by the conjugation with phosvitin and {TEX}$$\alpha$_{s}${/TEX}-casein. Emulsion stability of the curdlan-phosvitin conjugate was about 2.9 times greater than that of the curdlan-phosvitin mixture.

Production and Use of Maillard Products as Oxidative Stress Modulators

Soichiro Nakamura,Hao Jing 한국식품영양과학회 2005 Journal of medicinal food Vol.8 No.3

The Maillard reaction (MR) involves the reaction of carbonyl groups of monosaccharides or polysaccharidesand amino groups of amino acids or proteins. There is increasing recognition of the role of the MR in food science and tech-nology. The MR plays an important role in the development of color, aroma, texture, and nutritional value of food products.This review is mainly focused on the preparation of model MR product (MRP) of amino acid/monosaccharides and pro-tein/polysaccharide, antioxidant effects of amino-sugar MRPs and protein-polysaccharide Maillard-type neoglycoproteins, andsafety issues related to both types of the MRPs.

Rapid Formation of Biologically Active Neoglycoprotein from Lysozyme and Xyloglucan Hydrolysates through Naturally Occurring Maillard Reaction

Soichiro Nakamura,Masayoshi Saito,Tetsuhisa Goto,Hiroki Saeki,Masahiro Ogawa,Masayuki Gotoh,Yasuhide Gohya,Jae-Kwan Hwang 한국식품영양과학회 2000 Preventive Nutrition and Food Science Vol.5 No.2

Hen egg-white lysozyme was conjugated with 7~9 mers xyloglucan hydrolysates (MW=1,400) at 60℃ and 79% relative humidity for 3 days. SDS-PAGE showed that the conjugation between lysozyme and the oligosaccharide began from 1-day incubation, and three molecules of carbohydrate chains were attached to a protein molecule after 3-day incubation. The enzymatic activity of lysozyme was totally conserved in the neoglycoprotein, when measured by using glycol chitin as substrate. Besides, the emulsifying properties of lysozyme were vastly improved by the conjugation with the oligosaccharide, in which emulsifying activity of the neoglycoprotein was five times higher than that of native one.

In Vitro Anti-Cancer Activities in Caco-2 and HCT-116 Cells of Recombinant Cystatin C Prepared by a Pichia Expression System

Soichiro Nakamura,Masahiro Ogawa,Hao Jing,David D. Kitts,Shuryo Nakai 한국식품영양과학회 2003 Journal of medicinal food Vol.6 No.4

Caco-2 and HCT-116 cells were used to access growth-inhibition and anti-invasion activity of recombinantcystatin C expressed in Pichia pastorisX33, G12W/H86V. The mutant G12W/H86V prepared by a pilot plant productionsystem showed more than 10% growth inhibition of Caco-2 cells at 0.56 56 n M concentrations. Growth-inhibited cells hadlower cathepsin L activity than the control cells that were not treated with the inhibitor. Conversely, the cathepsin B activitywas not changed by treatment with G12W/H86V. The in vitroanti-invasion test using HCT-116 cells showed that G12W/H86Vsuppressed the cell invasion by 15%, while its wild-type cystatin, aspartic protease inhibitor pepstatin A, and matrix metal-loproteinase (MMP) inhibitor MMP-2/MMP-9 inhibitor III did not supress cell invasion. These results indicate that the re-combinant cystatin C with higher protease inhibitory activity effectively retards the growth and invasiveness of human coloncarcinoma cells.

Biomolecular Strategies for Preparation of High Quality Surimi - Based Products

Soichiro Nakamura,Masahiro Ogawa 한국식품영양과학회 2005 Preventive Nutrition and Food Science Vol.10 No.2

There exist two interesting phenomena in making seafood products from surimi. When salted surimi is kept at a constant low temperature (4~40℃), its rheological properties change from sol to gel, which is called “setting”. Seafood processors can exploit changes that occur during setting in preparation of surimibased products, because heating at high temperatures, after the pre-heating during the setting process, enhances the gel-strength of salted surimi. Contrarily, when salted surimi or low-temperature set gel is heated at moderate temperatures (50~70℃), a deterioration of gel is observed. The phenomenon is termed “modori”. In the modori temperature range, heat-stable cysteine proteinases such as cathepsin B, H, L and L-like hydrolyze the myosins responsible for gel-formation, resulting in gel weakening modori. This article reviews molecular events occurring during gel setting that improve the quality of surimi-based products, and inhibition of modori by applying proteinase inhibitors. Application of recombinant protein technology to surimi-based products is introduced and its prospects for practical use are discussed.

Improving the Surface Functionality of Curdlan by Conjugation with Unfolding Protein through Naturally Occurring Maillard Reaction

Soichiro Nakamura,Masahiro Ogawa,Hiroki Saeki,Masayoshi Saito,Satoko Miyasaka,Junya Hata,Naoko Adachi,Jae-Kwan Hwang 한국식품영양과학회 2000 Preventive Nutrition and Food Science Vol.5 No.4

Protein conjugation of curdlan belonging to β-1,3-glucan was carried out to improve its surface functionalities. The glucan was mixed with phosvitin, α_s-casein, lysozyme or ovalbumin, respectively. The mixture was freeze-dried, and the resulting powder was incubated at 60℃ and 79% relative humidity for 12 days in order to generate a controlled Maillard reaction between curdlan and proteins. Conjugation with unfolding proteins, i.e., phosvitin and α_s-casein, drastically increased the solubility of the glucan, whereas lysozyme and ovalbumin did not. The solubility in water of curdlan was 3.44% for the phosvitin conjugate and 1.09% for the α_s-casein conjugate. SDS-slab polyacrylamide gel electrophoresis showed that curdlan was solubilized due to covalent binding with phosvitin. Emulsifying properties of curdlan were substantially improved by the conjugation with phosvitin and α_s-casein. Emulsion stability of the curdlan-phosvitin conjugate was about 2.9 times greater than that of the curdlan-phosvitin mixture.

Food Safety of Functional Neoglycoproteins Prepared by Covalent Attachment of Galactomannan to Food Proteins

Nakamura, Soichiro,Dokai, Kazumi,Matsuura, Megumi,Hata, Junya,Saeki, Hiroki The Korean Society of Food Science and Nutrition 2002 Preventive Nutrition and Food Science Vol.7 No.2

Hen egg-white lysozyme, ovalbumin, egg-yolk phosvitin, acid-precipitated soy protein and $\alpha$$_{sl}$ milk casein were covalently linked with galactomannan through a controlled dry-heating at 6$0^{\circ}C$ under 79% relative humidity without any chemical reagent. Neoglycosylation by the covalent binding of polysaccharide chains brought a significant improvement into the surface functionalities of food proteins. Excellent emulsifying properties and foaming properties were observed in all protein-galactomannan conjugates. Bacterial mutagenesis tests and animal dose test were done to evaluate the food safety of the protein-galactomannan conjugates. The neo-glycoproteins were negative for Ames test using Salmonella typhimurium TA100 (hisG46) and TA98 (hisD3052) strains, and rec-assay using Bacillus subtilis Hl7 (rec) and M45 (re $c^{+}$) strains. All substances were also nontoxic for oral administration to rats. L $D_{50}$ 's of these substances were all more than 7.5 g/kg body-weight of rat. No effect was also observed in the weight increases and the concentrations of total cholesterol, triglyceride and phospholipids in blood serum of the administrated rats with 7.5 g/kg conjugates. Thus, Maillard-type protein-polysaccharide conjugates prepared by covalent attachment of galactomannan to food proteins were proposed to be useful as a safe functional biopolymer in this study.y.

Food Safety of Functional Neoglycoproteins Prepared by Covalent Attachment of Galactomannan to Food Proteins

Soichiro Nakamura,Kazumi Dokai,Megumi Matsuura,Junya Hata,Hiroki Saeki 한국식품영양과학회 2002 Preventive Nutrition and Food Science Vol.7 No.2

Hen egg-white lysozyme, ovalbumin, egg-yolk phosvitin, acid-precipitated soy protein, αs1 milk casein were covalently linked with galactomannan through a controlled dry-heating at 60℃ under 79% relative humidity without any chemical reagent. Neoglycosylation by the covalent binding of polysaccharide chains brought a significant improvement into the surface functionalities of food proteins. Excellent emulsifying properties, foaming properties were observed in all protein-galactomannan conjugates. Bacterial mutagenesis tests, animal dose test were done to evaluate the food safety of the protein-galactomannan conjugates. The neoglycoproteins were negative for Ames test using Salmonella typhimurium TA100 (hisG46), TA98 (hisD3052) strains,, rec-assay using Bacillus subtilis H17 (rec^-), M45 (rec^+) strains. All substances were also nontoxic for oral administration to rats. LD_(50)’s of these substances were all more than 7.5 g/kg body-weight of rat. No effect was also observed in the weight increases, the concentrations of total cholesterol, triglyceride, phospholipids in blood serum of the administrated rats with 7.5 g/kg conjugates. Thus, Maillard-type proteinpolysaccharide conjugates prepared by covalent attachment of galactomannan to food proteins were proposed to be useful as a safe functional biopolymer in this study.

Biomolecular Strategies for Preparation of High Quality Surimi-Based Products

Nakamura Soichiro,Ogawa Masahiro The Korean Society of Food Science and Nutrition 2005 Preventive Nutrition and Food Science Vol.10 No.2

There exist two interesting phenomena in making seafood products from surimi. When salted surimi is kept at a constant low temperature $(4\~40^{\circ}C)$, its rheological properties change from sol to gel, which is called 'setting'. Seafood processors can exploit changes that occur during setting in preparation of surimibased products, because heating at high temperatures, after the pre-heating during the setting process, enhances the gel-strength of salted surimi. Contrarily, when salted surimi or low-temperature set gel is heated at moderate temperatures $(50\~70^{\circ}C)$, a deterioration of gel is observed. The phenomenon is termed 'modori'. In the modori temperature range, heat-stable cysteine proteinases such as cathepsin B, H, Land L-Iike hydrolyze the myosins responsible for gel-formation, resulting in gel weakening modori. This article reviews molecular events occurring during gel setting that improve the quality of surimi-based products, and inhibition of modori by applying proteinase inhibitors. Application of recombinant protein technology to surimi-based products is introduced and its prospects for practical use are discussed.

Relationship between Skeletal Muscle Mass, Bone Mineral Density, and Trabecular Bone Score in Osteoporotic Vertebral Compression Fractures

Tokeshi Soichiro,Eguchi Yawara,Suzuki Munetaka,Yamanaka Hajime,Tamai Hiroshi,Orita Sumihisa,Inage Kazuhide,Shiga Yasuhiro,Hagiwara Shigeo,Nakamura Junichi,Akazawa Tsutomu,Takahashi Hiroshi,Ohtori Seij 대한척추외과학회 2021 Asian Spine Journal Vol.15 No.3

Study Design: A retrospective observational study was performed. Purpose: We investigated the relationships between skeletal muscle mass, bone mineral density (BMD), and trabecular bone score (TBS) in patients with osteoporotic vertebral compression fractures (VCFs). Overview of Literature: The TBS has attracted attention as a measurement of trabecular bone microarchitecture. It is derived from data obtained using dual-energy X-ray absorptiometry (DXA) and is a reported indicator of VCFs, and its addition to the Fracture Risk Assessment Tool increases the accuracy of fracture prediction. Methods: BMD, skeletal muscle mass, and TBS were measured in 142 patients who visited Shimoshizu National Hospital from April to August 2019. Patients were divided into a VCF group and a non-VCF group. Whole-body DXA scans were performed to analyze body composition, including appendicular skeletal muscle mass index (SMI; lean mass [kg]/height [m2]) and BMD. The diagnostic criteria for sarcopenia was an appendicular SMI <5.46 kg/m2. A logistic regression analysis was conducted to identify the risk factors for VCFs. Results: The significant (p<0.05) findings (VCF group vs. non-VCF group, respectively) included age (79 vs. 70 years), femoral BMD (0.50 vs. 0.58 g/cm2), TBS (1.25 vs. 1.29), and lower limb muscle mass (8.6 vs. 9.9 kg). The VCF group was significantly older and had a lower femur BMD and decreased leg muscle mass than the non-VCF group. Based on the multiple logistic regression analysis, lower femoral BMD and decreased leg muscle mass were identified as risk factors for vertebral fracture independent of age, but the TBS was not. Conclusions: Patients with VCFs had low BMD, a low TBS, and low skeletal muscle mass. Lower femoral BMD and decreased leg muscle mass were identified as risk factors for VCFs independent of age, whereas the TBS was not identified as a risk factor for VCFs.