Research Reports No.20 Abstract（2014）
20-01
Development of a novel web-database that enables to retrieve microbial growthinhibition of food additives
Shigenobu Koseki
Research faculty of Agriculture, Hokkaido University
Quantitative information regarding the growth inhibition effects of food additives, such as preservatives, remains insufficient. Most food processing companies need to know the effects of preservatives to ensure the microbial safety and quality of processed foods. In particular, spoilage induced by bacteria such as lactic acid bacteria (LAB) is a great concern. To provide information about the effects of various food preservatives, we quantitatively investigated these effects on the growth of LAB. Furthermore, predictive models were developed to describe the specific growth rate
(umax) and lag time (λ). We examined the following preservatives approved in Japan: thiamine dilauryl sulphate, sodium acetate, sorbic acid, calcium propionate, lysozyme, adipic acid, protamine and glycine. Depending on the nature of each preservative, 8 different concentrations of these chemicals were dissolved in MRS broth. The bacterial strains used in the present study were Enterococcus faecalis,Lactobacillus acidophilus and L. brevis. We examined 320 conditions that comprised 8 preservatives at 8 concentrations under 5 temperature conditions. LAB growth was continuously evaluated by observing the changes in optical density (OD) at 595 nm in 96-well micro plates. The changes in OD595 values were fitted to a logistic equation, and the growth parameters, umax and λ, were estimated by the 2-fold dilution method. The umax and λ were significantly influenced by each preservative concentration of each and incubation temperatures. Theumax was described using a model based on the gamma concept as a function of temperature and each preservative concentration. The λwas described using a hyperbola model as a function of temperature and each preservative concentration. The accuracy of these secondary models for umax and λ was overall acceptable. The present study will provide useful information for food processing companies to design products reasonably considering the quantity of the preservatives.
20-02
eduction of Radioactive Cesium in Pickled Plum and Plum Liquor by Zeolite
Haruhito Sekizawa, Katsuo Tanji, and Kunio Yoshioka
Fukushima Agricultural Technology Centre
Zeolite, which is used as an absorbent in food production and is designated as a food additive, is known to absorb radioactive cesium by its capability of cation exchange. In this study, we investigated the effect of zeolite treatment for the removal of radioactive cesium in pickled plum and plum liquor processing. A processing factor(Pf) was obtained by calculating the cesium concentration ratio of the processed products vs. raw materials. The processing factor is as follows. In pickled plum processing, Pf of not adding zeolite is 0.79, adding 10% and 20% zeolite was 0.43, processed with brine by adding 10% zeolite was 0.24, adding 10% granulated zeolite which is larger particle size was 0.58. On the other hand, In plum liquor processing, Pf of not adding zeolite is 0.24, adding 10% zeolite was 0.15, 20% zeolite was 0.09, 10% granulated zeolite which is larger particle size was 0.14. These results suggested that it is possible to reduce the radioactive cesium of pickled plum and plum liquor By addition of zeolite in pickled plum and plum liquor processing
20-03
Prevention against zinc deficiency by the use of food additives increasing zincabsorption in the intestinal epithelial cells
Taiho Kambe
Graduate School of Biostudies, Kyoto University
Shortage of dietary zinc puts human health at risk, because zinc is required for multiple physiological functions. Hence, a food-based strategy enabling efficient zinc absorption should be extensively explored. In the small intestine, the zinc transporter ZIP4/Slc39a4 functions as an essential component for zinc absorption, and thus food components with the activity of increasing ZIP4 expression may be a potential enhancer of zinc absorption. In this study, we examined the efficacy of food additives to increase ZIP4 expression. We found the effects of the food additives on increasing cellular zinc contents, which we previously identified the ability to increase ZIP4 expression. Moreover, we found the effects on ZIP4 expression in the small intestine of rats fed with zinc adequate or deficient diet supplemented with the food additives, although could not yet observe increasing serum zinc levels. Some food additives may have the potential to increase ZIP4 expression and thus increase zinc absorption.
20-04
Study on safety and efficacy of antioxidants using electron spin resonance
Yusuke IWASAKI
Department of Analytical Chemistry, Hoshi University School of Pharmacy and Pharmaceutical Sciences
Food additives, such as preservatives, sweeteners, coloring agents, and flavoring agents, are commonly used in food manufacturing. However, their combined effects on the human body are not known. The purpose of this study was to determine the effects of the simultaneous intake of antioxidant and metal ion on reactive oxygen species (ROS) generation. We investigated the interaction of antioxidant with metal ion under in vitro conditions using electron spin resonance (ESR). Minerals and trace elements, with the exception of iron and copper, did not generate ROS in the presence of an antioxidant. Moreover, specific antioxidants having pro-oxidant activity affected DNA oxidation and degradation by the generated ROS.
20-05
Analytical study on the bromate residue in foods disinfected with hypochlorite reagents
Ichiro Koshiishi
Graduate School of Gunma University, Faculty of Health Sciences
In our recent study, we established a novel analytical method for the quantification of bromate in the fresh foods that is based on HPLC with post-column derivatization using tetramethylbenzidine. The lowest quantification limit in fresh foods was estimated to be 0.6 ng/g as bromic acid. However, the sensitivity of this method is not enough to quantify the residual bromate especially in vegetables, which are treated with sodium hypochlorite solution for disinfection, because bromate is labile in the vegetables. In the present study, we established the pretreatment method, by which bromate at the less than 0.1 ng/g of wet weight level in vegetable was quantified.
20-06
Studies on the chemical structure and the mechanism for production of gardenia red
Yusai Ito
pision of food additives, National institute of health sciences
Gardenia red is hydrophilic colorant produced by the addition of an iridoid glucoside, geniposidic acid, prepared from geniposide of gardenia fruits by alkali hydrolysis to a mixture of -glucosidase and hydrolyzate of proteins. The colorant is a complex of high-molecular compounds, therefore the chemical structure of red pigments and the mechanism for producing the pigments have not been elucidated. Since genipinic acid was not prepared by the ester hydrolysis of a reagent of genipin, the iridoids were prepared from dried fruits of gardenia. The reaction of iridoids and glycine in an aqueous mixture did not produce red pigment but blue pigments, contrary to expectation. However, the addition of citric acid and xylose to the mixture and the anaerobic condition of the mixture by a bubbling of N2 gas showed to produce red pigments. Furthermore, the higher concentration of iridoids (>15% (w/v)) in reaction mixture tended to produce more red pigments and the production of CO2 gas in the mixture was observed when the concentration of iridoids increased. These findings suggested that the production for red pigments needs to keep a reductive condition in the reaction mixture. The addition of L-ascorbic acid to the mixture leaded to produce red pigment without the addition of citric acid and the bubbling of N2 gas to the mixture.
20-07
Involvement of multiple cell cycle aberrations in early preneoplastic liver cell lesions by tumor promotion with thioacetamide in a two-stage rat hepatocarcinogenesis model
Makoto Shibutani
Tokyo University of Agriculture and Technology, Graduate School, pision of Animal Life Science, Institute of Agricultural Science
Thioacetamide (TAA) induces oxidative stress and hepatocarcinogenicity in rats. We previously reported that TAA promotion caused various disruptions in cell cycle protein expression in rats, including downregulation of p16Ink4a, which is associated with intraexonic hypermethylation in hepatocellular proliferative lesions. This study further investigated the contribution of cell cycle aberrations associated with early hepatocarcinogenic processes induced by TAA using antioxidants, enzymatically modified isoquercitrin (EMIQ) and 疝och-lipoic acid (ALA), in a two-stage rat hepatocarcinogenesis model. TAA-promotion after initiation with N-diethylnitrosamine increased the number and area of hepatocellular foci immunoreactive for glutathione S-transferase placental form (GST-P) and the numbers of proliferating and apoptotic cells. Co-treatment with EMIQ and ALA suppressed these increases. TAA-induced formation of p16Ink4a－ foci in concordance with GST-P+ foci was not suppressed by co-treatment with EMIQ or ALA. TAA-promotion increased cellular distributions of cell proliferation marker Ki-67, G2/M and spindle checkpoint proteins (phosphorylated checkpoint kinase 1 and Mad2), the DNA damage-related protein phosphorylated histone H2AX, and G2-M phase-related proteins (topoisomerase II疝och, phosphorylated histone H3 and Cdc2) within GST-P+ foci, and co-treatment with EMIQ or ALA suppressed these increases. These results suggest that downregulation of p16Ink4a may allow selective proliferation of preneoplastic cells by TAA promotion. However, antioxidants did not counteract this gene control. Moreover, effective suppression of TAA-induced cellular population changes within preneoplastic lesions by antioxidants may reflect facilitation of cell cycling and accumulation of DNA damage causing the activation of cell cycle checkpoints, leading to G2 and M phase arrest at the early stages of hepatocarcinogenesis promoted by TAA.
20-08
Studies on the effect on the masking of bitterness by the sweet-tasting protein, thaumatin
Tetsuya Masuda
pision of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University,
Sweet-tasting protein, thaumatin elicits a sweet taste at 50 nM. Extensive sweet sensations of thaumatin are widely used as sweeteners in food industries. Besides their unique properties as sweeteners it has also been suggested thaumatin potentially masks a bitter taste and enhances flavour of food stuck. However, such alternative properties on thaumatin besides sweeteners have not fully understood. In the present study, to clarify the effect of the masking of bitterness by thaumatin, we prepared the HEK cells stably expressing bitter receptors.
20-09
Application of quantitative NMR spectroscopy for the quality evaluation of food additives.
Kazuyoshi Terasaka
Department of Pharmacognosy, Graduate School of Pharmaceutical Sciences,Nagoya City University
Proton-specific quantitative NMR (qHNMR) spectroscopy is a powerful tool for quantitative determination of organic molecules. There are still some food additives on the List of Existing Food Additives, prepared by the Ministry of Health, Labour and Welfare of Japan, that have no established quantification method. In the present study, we demonstrated whether qHNMR spectroscopy could be effectively applied for the quantitative determination of myricitrin and glycyrrhizic acid in commercial preparations of 'Chinese bayberry extract' and 'Licorice extract', respectively. The results suggested that the myricitrin content of Chinese bayberry extract could be determined by qHNMR spectroscopy, but the quantitative determination of glycyrrhizic acid in Licorice extract is difficult due to the signals of interference compounds.
20-10
Evaluation of immunotoxicity of nanomaterials in foods
Yasuo Yoshioka
Laboratory of Toxicology and Safety Science, Graduate School of Pharmaceutical Sciences, Osaka University
A nanomaterial is defined as a substance that has at least one dimension of less than 100 nm in size. Nanomaterial has been applied in various kinds of fields. For example, amorphous silica nanoparticles (nSP) have been already used in various foods as anticaking agents. Therefore, we cannot avoid uptake of nSP by oral route. Under this circumstance, there is increasing the importance of ensuring the safety of nanomaterial in foods. We previously revealed uptake of food antigens with nSP might induce excessive immune response to food antigens and then induce the abrogation of immune tolerance to food antigens. Here, we examined the in vitro intestinal absorption of amorphous silica particles with diameters of 30, 70, 300 and 1000 nm (nSP30, nSP70, mSP300 and mSP1000, respectively). We also evaluated the absorption of nSP70 surface-modified with amine or carboxyl groups (nSP70-N or nSP70-C, respectively). Analysis of intestinal absorption by means of the everted sac method showed that absorption of nSP30 was significantly higher than that of other silica particles, and absorption of nSP70-N and nSP70-C was higher than that of nSP70. These results indicate that silica nanoparticles were absorbed through the intestine and that particle diameter and surface properties were major determinants of absorption.
20-11
Elucidation of the cancer-causing mechanism of the nongenotoxic liver carcinogen dammar resin in rats
Hideki Wanibuchi
Osaka city university graduate school of medicine, Department of molecular pathology
Dammar resin is a food additive primarily used as a thickening agent. We previously reported that dammar resin induced liver tumors in a rat two year carcinogenicity study and showed that it is negative for mutagenicity in a gpt delta rats. The purpose of this study is to clarify the mechanisms underlying the liver carcinogenesis induced by dammar resin in rats. 6 weeks old F344 rats were pided into 2 groups and were fed diet supplemented with dammar resin at doses of 0, 2.0 % (carcinogenic dose), for 4 weeks. Dammar resin administration significantly increased in mRNA expression of CYP1a1, 2b1, 2e1, 3a2, and 3a3. Furthermore, result of microarray and canonical pathway analysis revealed that AhR (Aryl hydrocarbon receptor) and PXR/RXR pathways were activated by dammar resin administration. AhR pathway is implicated in most of the biological responses to the environmental contaminant. PXR/RXR activation regulates several endogenous processes. We also selected the 16 DNA methylation abnormality candidates on the basis of results of microarray and bioinformatics analyses. In addition, expression levels of Dnmt3b that is involved in de novo methylation and Hdac that induces deacetylation of the histone, were decreased. These findings suggested that dammar resin induce liver carcinogenesis via non-genotoxic mechanisms including P450-mediated bioactiviation, activiation nuclear transcription factor and epigenetic modification
20-12
Functional estimation and identification of bioactive constituents of Citrus microcarpa Bunge from Okinawa
Hiroyuki Morita
pision of Natural Products Chemistry, Institute of Natural Medicine, University of Toyama
Citrus microcarpa Bunge is actually a hybrid of mandarin and the Japanese Kumquat (Citrus japonica). This citrus has been cultivated also in Okinawa. Interestingly, C. microcarpa Bunge produces two unique type III polyketide synthase, quinolinon synthase and acridone synthase, in which the former enzyme specifically catalyzes the formation of quinolinone scaffold while the other shows multifunction to yield acridone, benzophenone, and phlorogrucinol scaffolds along with chalcone scaffold. However, these types of compounds have never been isolated from this plant, suggesting that C. microcarpa Bunge might produce a variety of bioactive compounds including these types of compounds further. In this study, we investigated the constituent of C. microcarpa peel based on in vitro preferential cytotoxicity against pancreatic cancer cells. The CHCl3 extract from C. microcarpa peel, collected at Okinawa, displayed preferential cytotoxicity against a human pancreatic cancer PANC-1 and PSN-1 cell lines under nutrient-deprived medium. Furthermore, the isolation of secondary metabolites from the CHCl3 extract of this plant yielded 10 flavonoids, of which three flavonoids exhibited preferential cytotoxicity against these cell lines under nutrient-deprived-medium.
20-13
Study on a promotive effect of polysaccharides on excretion of radioisotopes
Shuichi Enomoto
Department of Pharmaceutical Analytical Chemistry, Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama University
The Fukushima nuclear accident occurred, radionuclides containing 137Cs, 131I and 90Sr were released into the environment. At present, people are concerned about internal exposure via foods contaminated with radionuclides. Therefore, effective and easily obtained radioprotector is urgently needed. It has been shown that pectin promotes the excretion of 137Cs. However, the mechanism on how pectin affects the biodistribution of radionuclides remains unclear. In the present study, we analyzed biodistribution of radionuclides in order to reveal the effects of pectin intakes on the dynamics and excretion of radionuclides.Pectin was orally administrated to BALB/c mice for 1 week. On the 8th day, mice were injected intravenously with 137Cs, 131I and 85Sr. After 6 hours, the radioactivity of each tissue was determined by Ge detector. In addition, we evaluated biodistribution of radionuclides in case of pectin intakes for 1 week after injection of 137Cs, 131I and 85Sr.
There was no significant difference in biodistribution of radionuclides between pectin-treated mice and control mice. On the other hand, the excretion of radionuclides was promoted in pectin-treated mice. Therefore, pectin is a potential radioprotector to promote the excretion of radionuclides.
20-14
Functional evaluation of essential oils-derived chemicals for health promotion
Hiroyasu Inoue, Rieko Nakata
Department of Food Science and Nutrition, Nara Women's University
Cyclooxygenase-2 (COX-2), the rate-limiting enzyme in prostaglandin biosynthesis, plays a key role in inflammation and circulatory homeostasis. Peroxisome proliferator-activated receptors (PPARs) are ligand-dependent transcription factors belonging to the nuclear receptor superfamily and are involved in the control of COX-2 expression, and vice versa. Several natural chemicals such as resveratrol have been identified as suppressors of COX-2 expression and activators of PPARs. These two properties targeted to COX-2 and PPARs will be useful in evaluating functional food components against lifestyle-related diseases. In this study, we identified trans-cinnamaldehyde, a major component of cinnamon bark oil, as the suppressor of COX-2 expression and an activator of PPAR, / and in vitro. Trans-cinnamaldehyde decreased plasma triglyceride concentration in wild type, but not in PPAR knockout mice that inhibit aldehyde metabolism by cyanamide. Moreover, we found that benzyl-isothiocyanate activates PPAR in vitro and in vivo, and suppresses COX-2 expression in PPAR-independent manner. These results may be important for understanding the anti-lifestyle-related disease properties of trans-cinnamaldehyde and benzyl-isothiocyanate.
20-15
Functionalization and Inclusion of Polyphenols by using Saccharide Chains
Yoshiaki Yuguchi
Faculty of Engineering, Osaka Electro-Communication University
We reported the interaction between saccharide chains and EGCG molecules at previous research. The anti-oxidant activity for this system was examined by using fluorescent probes to evaluate the effect of addition of saccharide chains. As a result that effect was detected. The method for mixing the samples was also influenced for activity and relative reactivity. The samples mechanically mixed at paste state marked higher anti-oxidant activity and lower relative reactivity as compared with mixed at solution state.
20-16
Characterization and classification of Zinger extract using 1H-NMR meabolomics
Daigo Wakana1)、Takuro Maruyama2)、Koji Sugimura3)、Osamu Iida3)、Nobuo Kawahara3)
1) Department of organic chemistry、Hoshi University、 2) pision of pharmacognosy、 phytochemistry and narcotics、National Institute of Health Sciences、
3) Research center for medicinal plant resources、National Institute of Biomedical Innovation
Ginger (Zingiber officinale) is well-known spice and cultured on a temperate region。 We attempted to standardize the ginger using 1H-NMR-metabolomics because the standardization of the ginger has been provided by the quantity of one or a small number of compounds detected in ginger。 The score plot of principal component analysis (PCA) using 1H-NMR of the ginger aqueous extract showed some outliers。 The results of conducting PCA to the ginger extract except the outliers showed that there are differences between Kintoki species and Amami native species、 and between China L5 species and Sanshu Kochi species、 China L4 species。 Furthermore、 we tried to OPLS-DA to evaluate the varietal variation in chemical components。 The results showed that sucrose、 glucose、 alanine、 arginine、 asparagine、 malic acid and gingerol are important factors for the classification of the ginger。
20-17
Analysis of promoting gastrointestinal absorption using nanofood additives
Akira ONODERA1, Maiko OHATA1, Atsumi HIROUCHI1, Shigenobu YONEMURA2, Yuichi KAWAI1
Department of Pharmaceutical Sciences , Kobegakuin University1 RIKEN CDB2
Anorexia and hypoalimentation associated with aging and old age are caused by various factors. We investigated the association between nanofood additives and the membrane permeability of intestinal epithelial cells for the purpose of enhancing gastrointestinal absorption function using food additives. The nanomaterials used were amorphous silica and silver in the form of particulate food matter. Amorphous silica particles had a primary particle size of 300 nm and 70 nm (nSP300 and nSP70, respectively), whereas silver particles had a primary particle size of 70 nm and 1 nm (nAg70 and nAg1, respectively). Cytotoxicity has been reported for these materials. Thus, we observed the formation of tight junctions (TJs), which are a barrier structure of intestinal epithelial cells. In addition, we used human intestinal epithelial-like Caco-2 cells induced by the BioCoatTM HTS Caco-2 assay system. We treated intestinal epithelial cells for 24 h with 50 lochg/mL amorphous silica and silver particles to assay their effect on the formation of TJ. Fluorescent immunostaining of the TJ constitution marker, zonula occludens-1 (ZO-1), was observed using a FluoView FV1000 confocal laser scanning microscope (Olympus). As a result, on treatment with nSP70, nSP300, and nAg70, no disorders of TJ structure and cell release by cell death were observed. On the other hand, treatment with nAg1 caused expansion of the intercellular space and release of some cells. Next, we evaluated the effect of these particles on membrane permeability using transepithelial electrical resistance (TEER), which is an index of TJ. A low TEER value indicates enhanced membrane permeability. On treatment with 50 lochg/mL nSP70, TEER values decreased to 90% and 70% for 1 h and 24 h, respectively; on treatment with 50 lochg/mL nSP300, TEER values decreased to 85% for 24 h, but no decrease was observed for 1 h. On treatment with 50 lochg/mL nAg70, TEER values decreased to 60% for 1 h and recovered to 100% for 24 h; on treatment with 50 lochg/mL nAg1, TEER values decreased to 0% for 1 h and 24 h. The above results suggest that membrane permeability is actually more enhanced with silver particles rather than amorphous silica particles, and nAg1 is considered to cause strong cytotoxicity in the present study. However, the mechanism for nAg70 temporarily enhancing membrane permeability remains unclear. Gastrointestinal nutrient absorption can be roughly classified into the following three types: first, activation of ion channels and transporters; second, enhancement of membrane permeability; and third, expansion of the intercellular spaces by cell contraction. We focused on the third type and considered that intercellular spaces expanded by temporary cell constriction on treatment with nAg70. Thus, we assayed the effects of nAg70 on TEER by inhibiting a general cell contraction signal using Y27632. As a result, we found that enhanced membrane permeability caused by nAg70 was inhibited by Y27632. These results suggest that silver nanoparticles are effective for anorexia and hypoalimentation associated with aging and old age.
20-18
Molecular Behavior of Natural Food Additives, Glycyrrhizin on Lipid Rafts Biomembrane Model
Seiichi Sakamoto
Graduate School of Pharmaceutical Sciences, Kyushu University
Interfacial behavior of the aglycon of glycyrrhizin (GC), glycyrrhetinic acid (GA), with lipid raft model consisting of equimolar ternary mixtures of N-palmitoyl sphingomyelin (PSM), dioleoylphosphatidylcholine (DOPC), and cholesterol (CHOL) was systematically investigated by the Langmuir monolayer. The surface pressure (n)- molecular area (A) and surface potential (△V)-A isotherms showed that the adsorbed GA at the air/water interface was desorbed into the bulk upon compression of the lipid monolayer at all CGA investigated. In situ morphological analysis by Brewster angle microscopy and fluorescence microscopy revealed that the raft domains became smaller as CGA increases, suggesting that GA promotes formation of fluid networks related to various cellular processes via lipid rafts. In addition, ex situ morphological analysis by atomic force microscopy revealed that GA and GC lie down at the surface during interaction with lipid rafts. Interestingly, the distinctive striped regions were formed at CGA = 5.0 lochM, which indicates that GA pides the ternary monolayer into pieces upon compression. This phenomenon was found to be induced by the interaction of CHOL with adsorbed GA and is involved in membrane-disrupting activity of saponin and its aglycon. Quantitative comparison of GA with GC reveals that GA interacts more strongly with the raft model than GC in the monolayer state. It is well-known that various biological activities of GA are stronger than GC. This fact allows us to postulate that differences in interaction of GA/GC with the model monolayer correlate the degree of exertion for numerous activities.
20-19
Research on pharmacokinetics and physiological function of tocotrienol
Tsuyoshi Tsuduki
Graduate School of Agricultural Science, Tohoku University, Sendai 981-8555, Japan
We recently reported that tocotrienol (T3) had a potential to improve allergic reaction. The goal of this study was to examine the influence of T3 administration on liver lipid metabolism in allergia-induced mice. A model of atopic dermatitis was caused in NC/Nga mice treated with picryl chloride to induce allergic reaction. Allergia-induced mice caused lipid accumulation in the liver. On the other hand, T3 administration attenuated the liver lipid accumulation. The expression levels of the genes related to the liver lipid metabolism in the liver was examined using DNA microarray analysis and quantitative RT-PCR. Allergic reaction caused upregulation of Cdkn1a, which is strongly associated with lipid accumulation, and downregulation of Acox1, which is associated with fatty acid -oxidation, in the liver of allergic mice. In the liver of T3-administered allergic mice, the changes in the expression levels of Cdkn1a and Acox1 were not observed. These results suggest that T3 administration can improve the disturbance of liver lipid metabolism induced by allergic reaction.
20-20
Metabolites of ellagitannins and their anti-inflammatory effects
Hideyuki Ito
Department of Nutritional Science, Faculty of Health and Welfare Science, Okayama Prefectural University
Ellagitannins contain several food additives including Pimento, Melaleuca, Eucalyptus, and Pomegranate. These ellagitannins possess characteristic structures such as macrocyclic ring and gallagyl group. Pomegranate is abundant in punicalagin having the gallagyl group. We investigated exploring metabolites derived from gallagyl moiety in gut microflora suspension with punicalagin or rat urine after administration of punicalagin. We further tested for inhibitory effects of pomegranate extract and oenothein B, a major ellagitannin oligomer in pomegranate arils, against histamine synthase enzyme. Rat urine samples after oral administration of punicalagin with gallagyl and hexahydroxydiphenoyl (HHDP) groups and punicalin with only gallagyl group were evaluated by using DAD-HPLC. M1 (urolithin A) was observed 12-96 h after the ingestion of punicalagin, suggesting that HHDP group in the molecule was converted to M1. However, M1 was also detected after 12-72 h prior to the ingestion of punicalin, implying that M1 was produced from the gallagyl moiety through ellagic acid. The other unidentified metabolites were observed as the peaks with shorter retention volumes in urine samples. Isolation and characterization of the metabolites corresponding to these peaks are now in progress. Furthermore, oenothein B showed inhibitory effect on histamine synthase enzyme.
20-21
Study on the relationship between the chemical structure and biological activity in spice flavor constituents
Takao Koeduka
Faculty of Agriculture, Yamaguchi University
Since antiquity, human has historically used spices and herbs containing phenylpropenes as food preservative and cosmetics because of their pleasant aroma and antimicrobial properties. Many compounds belonging to the phenylpropene class differ from one another in two aspects: (1) the substitution pattern of the benzene ring (C6) and (2) the position of the double bond in the propenyl (C3)-side chain. However, despite many previous studies on phenylpropene volatiles from medicinal herbs and spices, there are few reports regarding a relationship between the chemical structure and their biological activities. In this report, I investigated the acaricidal activities to examine the structure-activity relationship of phenylpropenes. The structure-activity relationship of a series of eugenol and its prenylated derivaties indicated that specific phenylpropenes including O-dimethylallyl eugenol and O-dimethylallyl 5-methoxyeugenol with a prenyl group had the potent acaricidal activities for spider mites, whereas eugenol and O-dimethylallyl guaiacol had no activities. The results suggested the importance of dimethylallyl group and propenyl-side chain for the structure-based design of new functional properties of phenylpropenes.
20-22
Development of novel control method for preventing food-poisoning using food additives derived from polyphenols
Yuko Shimamura
School of Food and Nutritional Sciences, University of Shizuoka
The aims of the present study are first to investigate the binding activities of food additives derived from polyphenols (n=28) to staphylococcal enterotoxin A (SEA), and second to examine the inhibitory effects of these food additives and its components on the production and toxic activity of SEA. As a result, 12 samples inhibited the binding affinity of the anti-SEA antibody to SEA. Although highly polymerized proanthocyanidins in apple extract was bound to SEA directly, lowly polymerized proanthocyanidins inhibited the toxic activity without binding to SEA. Hydroxyl group at position 3 of galloyl group in catechin structure was responsible for binding affinity to the SEA. However methylated-catechins (methyl group at position 3 or 4 of galloyl group) showed inhibitory effect on production and toxic activity of SEA. These results suggest that these inhibitory effects were not necessarily related to the binding affinity of SEA.
20-23
Preparation of profile on phytopathogenic fungi for preservatives
Kosuke Takatori1)、Atsuko Takahashi2)
1) Department of Agriculture, Tokyo University of Agriculture 2) Department of Science for Living, Junior College of Kiryu University
The preservative as the food additive is important for managing the microorganism. The evaluation to fungi was extremely little though the preservative had been evaluated for food poisoning bacteria like E. coli so far.
Then, the efficacy evaluation to fungi of the preservative was widely executed. That is, fungi that influenced the efficacious concentration was specified. And, the relation between the preservatives as the food additive and fungi was specified and near fungal resistance was specified invalidly. The profile was able to be made as a result. In addition, the focus was applied to phytopathogenic fungi, and the anti-fungal spectrum of the preservatives and the fungicides was brought together. It fell below ADI in all fungal strains in the sodium dehydroacetate and the potassium sorbate and growth was controlled. As for the fungicides, it has been understood that there is a remarkable difference in the MIC value by the strains, and the effect is different according to fungi.
In addition, the quantitative structure activity relationship to the fungi was verified. As for fungi that showed coefficients of determination of 0.5 or less, the MIC value hardly changed into the preservative and the fungicide.
20-24
Comparison in aroma volatiles in Zanthoxylum species and biosynthesis of the compound involved in characteristic citrus-like flavor.
Yoko Iijima
Department of Nutrition and Life Science, Kanagawa Institute of Technology
Japanese pepper (Zanthoxylum piperitum) is a native plant frequently used as a spice and food additive in Japan. Although there are many Zanthoxylum plants in the world, the classification of them is complicated. In this study, we collected eight kinds of Zanthoxylum plants, and the aroma profiles from their leaves were compared by GC-MS analysis. Multivariate analyses showed an isolated cluster of Z. piperitum plants by accumulation of high amount of citronellal. On the other hand, other Zanthoxylum plants contained some other monoterpenes and methyl ketones as main compounds. Next, biosynthesis mechanism of citronellal formation was investigated by enzymatic assay. The enzymatic assay using citral and NADPH with crude enzyme prepared from immature Japanese pepper, showed active to formation of citronellal and citronellol probably by double bond reductase. Therefore, we undertook to isolate citral double bond reductase gene from Japanese pepper.
20-25
Effects of adsorbed layer and dispersion state of oil droplets on flavor release from emulsions
Yasuki Matsumura, Mio Sasaki, Kentaro Matsumiya
Laboratory of Quality Analysis and Assessment, Graduate School of Agriculture, Kyoto University
Effects of oil droplet coalescence on the release of fruity aroma compounds from milk proteins or a modified starch-based solutions and emulsions were studied by static headspace-gas chromatography. While a coalescence promoter, diglycerol ester of oleic acid decreased the release of relatively hydrophobic ethyl pentanoate and ethyl hexanoate from sodium caseinate solution due to incorporation of the flavor compounds into the vesicles formed in the solution, the other coalescence promoter, an amylase did not significantly affect the flavor release from modified starch solution. For emulsions, the release of the hydrophobic flavor compounds was generally decreased as compared to the solutions, indicating that flavor compounds used in this research tend to dissolve into the dispersed oil phase. Coalescence of oil droplets was successfully induced by the coalescence promoters under static conditions. Evaluation of the flavor release from the emulsions exhibiting coalescence revealed that oil droplet coalescence does not necessarily affect the flavor release from oil-in-water emulsions.
20-26
Study of measure expressing food texture for eating ease based on physiological measurements of humans
Kohyama Kaoru
National Food Research Institute, National Agriculture and Food Research Organization
This study aimed to quantify effects of food mouthful size on mastication and swallowing behavior of humans. Eating effort while masticating solid foods represented by hydrocolloid gels varying texture was evaluated using electromyography (EMG). EMG activities from both sides of masseter muscles as jaw-closing muscles and the suprahyoid muscle as the jaw-opening muscle were recorded from 11 normal subjects who freely eat sample gels without any designated condition. To reduce mouthful size leads more mastication. When food size was doubled, time for oral processing, the number of chews, and the number of swallows became approximately 1.4 times and they were never greater than 2 times. EMG variables per chew were not significantly different between 3 mL and 6 mL of the same gels. Those observations were found for the different 5 types gels and for 2 types gels with similar fracture load but different fracture strain in wider range of mouthful size (3, 6, 12, and 24 mL). These results suggest that the mastication effort can be estimated quantitatively for hydrogel foods with wide range of texture. We can predict the oral processing time, numbers of chews and swallows and mastication effort for different mouthful size gels. To elucidate the effects of water volume on flow properties of bolus (passage time，maximum and mean velocities) at esophagus orifice using ultrasonic pulsed wave Doppler method. Five healthy males and five females were swallowed 3, 6, 9, 12 mL water. An ultrasound probe was placed against each subject's neck to observe the flow properties of bolus. The velocity spectra of the bolus at the esophagus orifice were analyzed. Our results revealed that velocity of bolus was affected by volume of water, and the passage time, maximum and mean velocities increased as the increase in volume. The mean velocity of water boluses was about 0.3 m/s but there was high speed component for every water amount.
20-27
The method for pharyngeal residue quantitatively using aroma
Kazuhiro Hori
pision of Dysphagia Rehabilitation, Niigata University Graduate School of Medical and Dental Sciences
Dysphagia may cause not only aspiration pneumonia and choking but also decrease of ADL and QOL. The pharyngeal residue relates with aspiration after swallowing and dirtiness in the pharynx, and it can lead aspiration pneumonia. However, the method which can assess the pharyngeal residue quantitatively had not established yet. In the present study, we measured the retro-nasal aroma though nasal cavity, investigated the temporal changes of retro-nasal aroma, and attempted to measure the pharyngeal residue.
In the result, the amount of test sample did not influence on the intensity of aroma, but the time until maximum intensity depended on the amount of test sample. Furthermore, the intensity of retro-nasal aroma had a correlation with hypo-pharyngeal swallowing pressure. When the intensity of aroma was measured during holding test sample in the pharynx, the intensity of retro-nasal aroma related to the amount of test sample in the pharynx.These results suggested that this method could measure temporal intensity of retro-nasal and estimate the pharyngeal residue.