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Flagellins from Pseudomonas syringae pv. glycinea race 4 and Pseudomonas syringae pv. tabaci 6605 have been found to be glycosylated. Glycosylation of flagellin is essential for bacterial virulence and is also involved in the determination of host specificity. Flagellin glycans from both pathovars were characterized, and common sites of glycosylation were identified on six serine residues (positions 143, 164, 176, 183, 193, and 201). The structure of the glycan at serine 201 (S201) of flagellin from each pathovar was determined by sugar composition analysis, mass spectrometry, and 1H and 13C nuclear magnetic resonance spectroscopy. These analyses showed that the S201 glycans from both pathovars were composed of a common unique trisaccharide consisting of two rhamnosyl (Rha) residues and one modified 4-amino-4,6-dideoxyglucosyl (Qui4N) residue, β-D-Quip4N(3-hydroxy-1-oxobutyl) 2Me-(1→3)-α-L-Rhap-(1→2)-α-L-Rhap. Furthermore, mass analysis suggests that the glycans on each of the six serine residues are composed of similar trisaccharide units. Determination of the enantiomeric ratio of Rha from the flagellin proteins showed that flagellin from P. syringae pv. tabaci 6605 consisted solely of L-Rha, whereas P. syringae pv. glycinea race 4 flagellin contained both L-Rha and D-Rha at a molar ratio of about 4:1. Taking these findings together with those from our previous study, we conclude that these flagellin glycan structures may be important for the virulence and host specificity of P. syringae. [ABSTRACT FROM AUTHOR]

Previously we revealed that flagellin proteins in Pseudomonas syringae pv. tabaci 6605 (Pta 6605) were glycosylated with a trisaccharide, modified viosamine (mVio)-rhamnose-rhamnose and that glycosylation was required for virulence. We further identified some glycosylation-related genes, including vioA, vioB, vioT, fgt1, and fgt2. In this study, we newly identified vioR and vioM in a so-called viosamine island as biosynthetic genes for glycosylation of mVio in Pta 6605 by the mass spectrometry (MS) of flagellin glycan in the respective mutants. Furthermore, characterization of the mVio-related genes and MS analyses of flagellin glycans in other pathovars of P. syringae revealed that mVio-related genes were essential for mVio biosynthesis in flagellin glycans, and that P. syringae pv. syringae B728a, which does not possess a viosamine island, has a different structure of glycan in its flagellin protein. [ABSTRACT FROM AUTHOR]

Abstract: Xylo-oligosaccharides containing 4-O-methyl glucuronic acid (MeGlcA) residues attached to two adjacent xylosyl residues and those with a single MeGlcA residue were isolated from partial acid hydrolyzates of the arabinoglucuronoxylans (AGX) from Japanese cedar (Sugi, Cryptomaria japonica) and Hinoki cypress (Chamaecyparis obtusa). The ratio of xylo-oligosaccharides with two MeGlcA residues and those with a single MeGlcA residue was about 1:3 for both Sugi and Hinoki. Four xylo-oligosaccharides with two MeGlcA residues were labeled at their reducing end with 2-aminobenzamide (2AB). The 2AB-labeled oligosaccharides (1–4) were structurally characterized using normal-phase liquid chromatography, electrospray-ionization mass spectrometry (ESI-MS), and nuclear magnetic resonance (NMR) spectroscopy. The signals in the 1H and 13C NMR spectra of the 2AB-labeled oligosaccharides were fully assigned using one- and two-dimensional NMR spectroscopy. [Copyright &y& Elsevier]

The article presents a study which investigates the importance of glycan structures attached to the serine residues in the virulence of Pseudomonas syringae pv. tabaci. It mentions that the Ser/Ala-substituted mutants were generated from the glycosilation site in order to determine the importance of the glycan structures to the virulence of P. syringae. The result shows that the flagellin molecule such as the S183 are needed on the virulence of the Pseudomonas syringae pv. Tabaci.

Glycosylation of flagellin contributes to swimming and swarming motilities, adhesion ability, and consequently virulence in Pseudomonas syringae pv. tabaci 6605. Glycans attached to six serine residues are located in the central region of the flagellin polypeptide. The glycan structure at position Ser 201 was recently revealed to consist of two l-rhamnoses and one modified 4-amino-4,6-dideoxyglucose (viosamine). To clarify the mechanisms for glycosylation of modified viosamine, genes encoding dTDP-viosamine aminotransferase ( vioA), dTDP-viosamine acetyltransferase ( vioB), and viosamine-derivative transferase ( vioT) were isolated and defective mutants were generated. MALDI-TOF–MS analysis of a lysyl endopeptidase-digested peptide including all six glycosylation sites from each flagellin indicated that the molecular masses of the three flagellin mutants were reduced with highly heterogeneous patterns at regular intervals of 146 Da in the mass range from m/ z 13,819 to 15,732. The data indicated that the glycopeptides obtained from mutants had glycans consisting only of deoxyhexose instead of the flagellin glycans including the viosamine derivatives determined previously. The motility and virulence on host tobacco leaves were strongly impaired in the Δ vioA mutant and were weakly reduced in the Δ vioB and Δ vioT mutant strains. These results suggest that the genes vioA, vioB, and vioT are essential for glycosylation of flagellin, and accordingly are required for bacterial virulence. [ABSTRACT FROM AUTHOR]

Abstract: The flagellin of Pseudomonas syringae pv. tabaci is a glycoprotein that contains O-linked oligosaccharides composed of rhamnosyl and 4,6-dideoxy-4-(3-hydroxybutanamido)-2-O-methylglucosyl residues. These O-linked glycans are released by hydrazinolysis and then labeled at their reducing ends with 2-aminopyridine (PA). A PA-labeled trisaccharide and a PA-labeled tetrasaccharide are isolated by normal-phase high-performance liquid chromatography. These oligosaccharides are structurally characterized using mass spectrometry and NMR spectroscopy. Our data show that P. syringae pv. tabaci flagellin is glycosylated with a tetrasaccharide, 4,6-dideoxy-4-(3-hydroxybutanamido)-2-O-methyl-Glcp-(1→3)-α-l-Rhap-(1→2)-α-l-Rhap-(1→2)-α-l-Rha-(1→, as well a trisaccharide, 4,6-dideoxy-4-(3-hydroxybutanamido)-2-O-methyl-Glcp-(1→3)-α-l-Rhap-(1→2)-α-l-Rha-(1→, which was identified in a previous study. [Copyright &y& Elsevier]

Abstract: High-temperature stress during grain ripening facilitates the formation of chalky grains through loose packing of amyloplasts. In the present study, the changes in water distribution in the developing caryopses by high-temperature stress were investigated by magnetic resonance imaging. Milky-white and white-cored types of chalky grains, which had chalkiness around the centre of the endosperm, were formed in a high percentage in a high-temperature condition by the middle dry-matter accumulating stage. Magnetic resonance images of the early stage caryopses in the high-temperature condition showed a lower water content around the centre of the endosperm, where the disorganized development of amyloplasts was observed by scanning electron microscopy. Transcripts for α-amylase were, however, not detected there in the early and middle stage, indicating that starch degradation by α-amylase was not the cause of the formation of these types of chalky grains. In the middle stage, water content in the central chalky part became higher than in the lateral translucent part. Loose packing of amyloplasts in the chalky part may allow pooling of water in the free spaces leading to the higher water content after the middle stage. Together with the results, the physiological mechanism for the formation of white-cored and milky-white grains that occurred by high-temperature stress was discussed. [Copyright &y& Elsevier]

Abstract: Soft electrons (low-energy electrons) have been reported to effectively disinfest grains contaminated with stored-product insects. In this study, brown rice grains infested with different ages of the maize weevil, Sitophilus zeamais Motschulsky, were exposed to soft electrons. Soft electrons at an acceleration voltage of 170kV effectively inactivated eggs, old larvae and pupae of the maize weevil, but could not completely inactivate young larvae. The locations of young larvae in rice grains were specified by magnetic resonance microimaging. Most of the larvae resided at the periphery of the grains while only a few at the center, which were assumed to get out of inactivation. This indicated that soft electrons with low penetration capacity could reach the most of weevil larvae in grains. Combination of soft-electron treatment and short time–low-dose phosphine fumigation achieved high mortality rate of S. zeamais. [Copyright &y& Elsevier]

Abstract: The effect of seasonings on the texture of cooked spaghetti was examined by sensory and shearing tests. Spaghetti tossed with sucrose, trehalose, salt, and monosodium glutamate and their mixture retarded deterioration of the firmness of spaghetti strands. To investigate the penetration of water and seasonings, maps of spin–spin relaxation time and their profiles from the center to the surface of a spaghetti strand were acquired by magnetic resonance imaging. The homogenization of moisture distribution in cooked spaghetti during holding was delayed temporarily by salt owing to a back current caused by the gradient of salt content on the surface immediately after tossing. Monosodium glutamate rapidly penetrated into spaghetti strands and caused water T2 decrease possibly owing to the decreased mobility of water molecules in starch gel, whereas the sweeteners hardly altered the T2 maps. Salt and monosodium glutamate are considered to retard more effectively the deterioration of firmness of spaghetti. [Copyright &y& Elsevier]

• Nitrification results in poor nitrogen (N) recovery and negative environmental impacts in most agricultural systems. Some plant species release secondary metabolites from their roots that inhibit nitrification, a phenomenon known as biological nitrification inhibition (BNI). Here, we attempt to characterize BNI in sorghum ( Sorghum bicolor). • In solution culture, the effect of N nutrition and plant age was studied on BNI activity from roots. A bioluminescence assay using recombinant Nitrosomonas europaea was employed to determine the inhibitory effect of root exudates. One major active constituent was isolated by activity-guided HPLC fractionations. The structure was analysed using NMR and mass spectrometry. Properties and the 70% inhibitory concentration (IC70) of this compound were determined by in vitro assay. • Sorghum had significant BNI capacity, releasing 20 allylthiourea units (ATU) g−1 root DW d−1. Release of BNI compounds increased with growth stage and concentration of supply. -grown plants released several-fold higher BNI compounds than -grown plants. The active constituent was identified as methyl 3-(4-hydroxyphenyl) propionate. • BNI compound release from roots is a physiologically active process, stimulated by the presence of . Methyl 3-(4-hydroxyphenyl) propionate is the first compound purified from the root exudates of any species; this is an important step towards better understanding BNI in sorghum. [ABSTRACT FROM AUTHOR]

Abstract: We report the first experimental determination of the carboxylate oxygen electric-field-gradient (EFG) and chemical shielding (CS) tensors in polycrystalline γ-glycine. Analysis of magic-angle spinning (MAS) and stationary 17O NMR spectra of [17O]-γ-glycine obtained at 9.4, 14.1, 16.4, and 18.8T yields the magnitudes of the 17O EFG and CS tensors and the relative orientations between the two tensors. Extensive quantum chemical calculations at both the restricted Hartree–Fock and density functional levels have been performed to present the absolute tensor orientations in term of the molecular frame. We have demonstrated that 17O NMR tensor information could be unambiguously derived by the multiple field analyses of stationary 17O NMR spectra. [Copyright &y& Elsevier]

Abstract: Twenty components extracted from the essential oil in the leaves of 172 samples of Perilla frutescens var. crispa (vegetable crop form), P. frutescens var. frutescens (oil crop form), the wild/weedy form of P. frutescens, and three wild Perilla species, Perilla citriodora, Perilla hirtella and Perilla setoyensis were analyzed using GC/MS. A wide range of essential oil components were found among the wild/weedy form of P. frutescens, whereas distinctive components were detected in each wild Perilla species. Egomaketone, asaron, methyleugenol and 4,6-dimethoxy- or 4,7-dimethoxy-5-(2-propenyl)-1,3-dioxaindan were detected from Perilla for the first time. Limonene derivatives, piperitone and piperitenone, were detected from P. citriodora. Discovery of the limonene derivatives in this Perilla species provides evidence of this wild species being a genome donor of P. frutescens, while limonene synthase has been considered to be a specific enzyme in cultivated P. frutescens. These results will be useful for the evaluation and utilization of Perilla genetic resources. [Copyright &y& Elsevier]

Abstract: Human African trypanosomiasis is undergoing an alarming rate of recrudescence in many parts of sub-Saharan Africa. Yet, there is no successful chemotherapy for the disease due to a limited number of useful drugs, side effects and drawbacks of the existing medication, as well as the development of drug resistance by the parasite. Here we describe a new lead anti-trypanosomal compound isolated from Kola acuminata (Makasu). We purified a proanthocyanidin by chromatographic procedures and confirmed its homogeneity and structure by Nuclear Magnetic Resonance and Matrix-Assisted Laser Desorption Ionisation Time-of-Flight mass spectrometry, respectively. In vitro, this compound potently induced growth arrest and lysis of bloodstream form trypanosomes in a dose- and time-dependent manner. In a mouse model, it exhibited a trypanostatic effect that extended the life of infected, treated animals up to 8 days post-infection against the 4 days for infected, untreated animals. The proanthocyanidin showed a low cytotoxicity against mammalian cells, whereas treated-BF showed massive enlargement of their flagellar pocket and lysosome-like structures caused by an intense formation of multivesicular bodies and vesicles within these organelles. The observed ultrastructural alterations caused rupture of plasma membranes and the release of cell contents, indicative of a necrotic process rather than a programmed cell death. Interestingly, the proanthocyanidin acted against BF but not procyclic form trypanosomes. This new anti-trypanosomal compound should be further studied to determine its efficacy and suitability as an anti-trypanosomal drug and may be used as a tool to define novel specific drug targets in BF trypanosomes. [Copyright &y& Elsevier]

Bacillus and Streptomyces species possess the ability to produce a variety of commercially important metabolites and extracellular enzymes. We previously demonstrated that antibiotic production in Streptomyces coelicolor A3(2) and Streptomyces lividans can be enhanced by RNA polymerase (RNAP) mutations selected for the rifampicin-resistant (Rif[sup r]) phenotype. Here, we have shown that the introduction of a certain Rif[sup r] rpoB mutation into a B. subtilis strain resulted in cells that overproduce an aminosugar antibiotic 3,3'-neotrehalosadiamine (NTD), the production of which is dormant in the wild-type strain. Mutational and recombinant gene expression analyses have revealed a polycistronic gene ntdABC (formally yhjLKJ) and a monocistronic gene ntdR (formally yhjM) as the NTD biosynthesis operon and a positive regulator for ntdABC, respectively. Analysis of transcriptional fusions to a lacZ reporter revealed that NTD acts as an autoinducer for its own biosynthesis genes via NtdR protein. Our results also showed that the Rif[sup r] rpoB mutation causes an increase in the activity of σ[sup A]-dependent promoters including ntdABC promoter. Therefore, we propose that unlike the wild-type RNAP, the mutant RNAP efficiently recognized the σ[sup A]-dependent promoters, resulting in the dramatic activation of the NTD biosynthesis pathway by an autoinduction mechanism. [ABSTRACT FROM AUTHOR]

Nagkesar (buds of Mammea longifolia) is extensively used in culinary preparations especially in spice blend in India. Previously thirteen compounds were identified from the medium polar fractions of methanol extract of buds of M. longifolia. In continuation of the study, the polar fraction of methanol extract exhibited stronger antioxidative and radical scavenging activities. An attempt was made to separate and identify the active compounds and found that those were proanthocyanidin oligomers with mean degree of polymerisation ranges from 2 to 10. This is the first report to indicate that Mammea buds contain antioxidant and radical scavenging procyanidin oligomers. [Copyright &y& Elsevier]

Saturation transfer difference (STD) NMR spectroscopy is a promising tool for rapid screening, identifying ligands that interact with a target protein, and characterizing the epitopes of the ligands. Gibbrellins (GAs) are a class of plant hormones and form a large family consisting of more than 120 members. A few of them, called “active” GAs, are considered to be perceptible to a receptor that remains unknown. We applied STD NMR spectroscopy to detect the binding activity and identify the binding epitope of gibberellin A3 (GA3) that is recognized by monoclonal antibody 4-B8(8)/E9. This is one of the antibodies that can mimic a GA receptor in the manner of recognition of active GAs. The information on the binding epitope, obtained by STD NMR, was in good agreement with that shown by analyzing the crystal structure of the antibody–GA4 complex. This suggests that STD NMR spectroscopy would be very useful to characterize the interaction between GAs and such binding proteins as GA-catabolic enzymes and receptors. [Copyright &y& Elsevier]

Investigates the regulatory mechanism for biosynthesis of antibiotic bacilysin in Bacillus subtilis using the transcriptional lacZ fusion system. Importance of a polycistronic operon and a monocistronic gene in the biosynthesis of bacilysin in Bacillus subtilis; Effect of disruption of the genes by plasmid integration on bacilysin production.

We show that selection of drug-resistant bacterial mutants allows the discovery of antibacterial compounds. Mutant strains of a soil-isolated Streptomyces species that does not produce antibacterials synthesize a previously unknown class of antibacterial, which we name piperidamycin. Overall, 6% of non-Streptomyces actinomycetes species and 43% of Streptomyces species that do not produce antibacterials are activated to produce them. The antibacterial-producing mutants all carried mutations in RNA polymerase and/or the ribosomal protein S12. [ABSTRACT FROM AUTHOR]

3- O -Substituted reducing aldoses are commonly unstable under heat treatment at neutral and alkaline pH. In this study, to evaluate the decomposition products, nigerose (3- O -α- d -glucopyranosyl- d -glucose) and 3- O -methyl glucose were heated at 90 °C in 100 mM sodium phosphate buffer (pH 7.5). Decomposition via β-elimination was observed that formed a mixture of 3-deoxy- arabino -hexonic acid and 3-deoxy- ribo -hexonic acid; upon further acid treatment, it was converted to their γ -lactones. Similarly, turanose (3- O -α- d -glucopyranosyl- d -fructose), a ketose isomer of nigerose, decomposed more rapidly than nigerose under the same conditions, forming the same products. These findings indicate that 3- O -substituted reducing glucose and fructose decompose via the same 1,2-enediol intermediate. The alkoxycarbonyl elimination of 3- O -substituted reducing glucose and fructose occurs readily if an O -glycosidic bond is located on the carbon adjacent to the 1,2-enediol intermediate. Following these experiments, we proposed a kinetic model for the3- decomposition of nigerose and turanose by heat treatment under neutral pH conditions. The proposed model showed a good fit with the experimental data collected in this study. The rate constant of the decomposition for nigerose was (1.2 ± 0.1) × 10−4 s−1, whereas that for turanose [(2.6 ± 0.2) × 10−4 s−1 was about 2.2 times higher. Image 1 • Nigerose and turanose are unstable against heat treatment under neutral pH. • The decomposition by heating results in formation of 3-deoxy-hexonic acids. • γ-Lactones are generated by acid treatment of 3-deoxy-hexonic acids. • The elimination occurs on the carbon adjacent to the 1,2-enediol intermediate. [ABSTRACT FROM AUTHOR]

Pancreatic islet β-cells weaken under oxidative stress. In this study, human pancreatic islet-derived 1.1B4 cells were exposed to H 2 O 2 and analysed using a human microarray, which revealed that heme oxygenase 1 ( HMOX1) , glutamate-cysteine ligase , early growth response 1 , nuclear receptor subfamily 4 group A member 3 ( NR4A3 ) and jun B proto-oncogene were upregulated, whereas superoxide dismutase 1 and catalase were not. Expression of NR4A3 rapidly increased after H 2 O 2 addition, and the 1.1B4 cells treated with siRNA targeting NR4A3 became sensitive to H 2 O 2 ; further, HMOX1 expression was strongly inhibited, suggesting that NR4A3 is an oxidative stress-responsive transcription factor that functions through HMOX1 expression in pancreatic islet β-cells. Expression of cyclin E1 and cyclin-dependent kinase 1 was also inhibited by siRNAs targeting NR4A3 .

We investigated the time-dependent acrylamide formation in mung bean sprouts during stir-frying under high and medium heat conditions. The acrylamide concentration range detected using the 3-mercaptobenzoic acid derivatization LC-MS/MS method was from below 29 ng/g [limit of detection (LOD)] to 6,900 ng/g. We also investigated the acrylamide levels in mung bean sprouts cooked using four methods while retaining their fresh firm texture using the thiosalicyclic acid derivatization LC-MS/MS method. The acrylamide concentration in microwave oven-cooked sprouts was below 16 ng/g (LOD). The samples cooked by stir-frying, parching, or boiling contained an acrylamide concentration above the LOD but below 42 ng/g [limit of quantification (LOQ)], except for one replicate of a stir-fried sample, whose acrylamide concentration was 42 ng/g. Bean sprouts are popular affordable vegetables, and when stir-fried, their acrylamide concentration is assumed to strongly affect the exposure of the Japanese population to acrylamide. Because the acrylamide concentration range of fried bean sprouts is as broad as mentioned above, the selection of a representative concentration value is difficult. A precise survey and data about acrylamide formation in relation to the bean sprout components before heating, their changes occurring during storage, and the cooking methods and conditions used are needed to estimate the exposure of the Japanese to acrylamide. Here, we showed that rinsing the sprouts before frying and frying them for a short time while mixing them well, while retaining the fresh firm texture to avoid burning and shriveling the sprouts is effective in decreasing the amount of acrylamide formed., Competing Interests: Conflict of Interest: The authors have no conflict of interest., (©2023 Food Safety Commission, Cabinet Office, Government of Japan.)

In this study, the genome sequences of two Basidiomycetous yeasts, Tremella yokohamensis and Tremella fuciformis, which have very similar morphological characteristics, were determined. The genomic sequence data obtained will be useful for understanding the taxonomy and metabolic-related genes of basidiomycete yeasts.

Abstract: Wild boar meat containing radioactive cesium (Cs) of approximately 1,000 Bq/kg (134Cs+137Cs) was processed into bacon, sausage, and ham. To understand the concentration and quantity change of radioactive Cs, the processing factor (Pf) and food processing retention factor (Fr) were calculated. The radioactive Cs quantity in the meat did not reduce during smoking. The dehydration-related meat mass reduction during smoking without decrease of radioactive Cs led to Cs condensation in the bacon compared with the raw rib meat before processing, resulting in a Pf of 1.18. Soaking in liquid, such as pickling in liquid and desalting or boiling in water, effectively removed radioactive Cs by leakage into water. Therefore, the Fr value of the boiled ham produced from a loin meat block through three liquid-soaking processes was 0.27. The Pf value of the boiled ham was 0.30 due to meat block mass reduction after boiling as a result of dehydration, along with protein thermal denaturation-related muscle tissue shrinkage. The steamed ham Fr value was 0.53, because the removal of radioactive Cs was less efficient by steaming than by boiling. The Pf value of the steamed ham was 0.54, almost the same as the Fr value, because the mass decrease rate was the same as the radioactive Cs decrease rate by steaming. The Fr and the Pf values of the boiled sausage, whose processing did not include soaking in the pickling liquid, were 0.64 and 0.62, respectively. Steaming the sausage meat did not remove radioactive Cs during the dehydration-related mass reduction, leading to Fr and Pf values of 1.01 and 1.17, respectively. This study found that processing into boiled ham was the most effective measure for reducing radioactive Cs quantity and concentration in raw meat. Processing into bacon and steamed sausage showed no Cs quantity reduction, with the moisture loss resulting in Cs condensation compared with the raw material., (Copyright ©, International Association for Food Protection.)

In this study, we investigated the possibility of the geographical origin discrimination between Japanese and Mexican kabocha pumpkin using δ 13 C and δ 18 O in lyophilized raw flesh. Kabocha harvested in Hokkaido, the major kabocha production area in Japan, could be discriminated against not only that grown in Mexico but also that in New Zealand. However, seasoning after cooking or processing affected the δ 13 C and the δ 18 O values. Crude fiber extraction eliminated the effect of seasonings and enabled the adoption of the δ 13 C and δ 18 O values in crude fiber for the geographical origin verification of kabocha even after cooking and processing. The usage of δ 13 C and the δ 18 O in crude fiber would extend the application possibilities of stable isotope analysis in the geographical origin determination of various cooked and processed vegetables and fruits as well as raw materials., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Aldose-ketose isomerization is commonly used to prepare rare oligosaccharides such as maltulose (4-O-α-d-glucopyranosyl-d-fructose) and lactulose (4-O-β-d-galactopyranosyl-d-fructose). However, both sugars are degraded under alkaline conditions via β-elimination, while their subsequent benzylic acid rearrangement leads to the formation of isosaccharinic acids. Here, we investigated the behavior of maltose and maltulose upon heating in phosphate buffer solution at pH 7.5. Maltose was initially isomerized into maltulose. Maltulose was degraded via β-elimination, followed by keto-enol tautomerization, which led to the formation of a 1,3-dicarbonyl intermediate bearing an aldehyde group at the C-1 position and a ketone group at the C-3 position. Subsequent hydrolysis of this intermediate afforded formic acid and 3-deoxy-d-glycero-pent-2-ulose (1) as the major products based on HPLC and NMR data. In contrast, the formation of isosaccharinic acid via benzylic acid rearrangement, not the 3-deoxypentulose, was reported under the strongly alkaline conditions (Knill and Kennedy, 2003). The heat treatment of 1→4 linked oligo- and polysaccharides possessing glucose or fructose residue at the reducing end under neutral pH conditions could be applied for the practical preparation of a 3-deoxypentulose., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Elution of cesium-137 ( 137 Cs) from tofu into water was investigated to know the behavior of 137 Cs during preservation and cooking. The food processing retention factor ( Fr ) reached 0.55 when tofu was soaked in water at a ratio of 1:2 w / w for 24 h at 4°C. Doubling the amount of water did not further significantly decrease Fr . When tofu was held in water at a ration of 1:2 w/w at a temperature of 80℃ for 50 min, Fr was 0.72. Increasing the amount of water to 10 times the tofu weight did not further reduce Fr significantly. Cesium-137 is mostly bound to tofu and does not freely diffuse into water. Tofu was then soaked in water at a ratio of 1:2 w/w at 4℃ for 24 h, placed in new water at a ratio of 1:2 w/w, and held at 80℃ for 50 min, resulting in an Fr 0.33. This value is close to an estimated Fr calculated by multiplying the Fr of 0.55 from soaking at 4°C by the Fr of 0.72 from the hot water treatment. The calculated Fr from soybeans sequentially processing into tofu, soaking tofu at 4°C for 24 h and in hot water at 80°C for 50 min was about 0.1, indicating 90% removal of 137 Cs. Degree of decrease in 137 Cs during preservation and cooking of tofu demonstrated in this study will be useful for exposure assessment of 137 Cs through oral intake of contaminated soybeans after processing and cooking., Competing Interests: Conflict of Interest: The authors have no conflict of interest., (©2020 Food Safety Commission, Cabinet Office, Government of Japan.)

We evaluated the stabilities of kojibiose and sophorose when heated under neutral pH conditions. Kojibiose and sophorose epimerized at the C-2 position of glucose on the reducing end, resulting in the production of 2- O -α-D-glucopyranosyl-D-mannose and 2- O -β-D-glucopyranosyl-D-mannose, respectively. Under weak alkaline conditions, kojibiose was decomposed due to heating into its mono-dehydrated derivatives, including 3-deoxy-2,3-unsaturated compounds and bicyclic 3,6-anhydro compounds. Following these experiments, we propose a kinetic model for the epimerization and decomposition of kojibiose and sophorose by heat treatment under neutral pH and alkaline conditions. The proposed model shows a good fit with the experimental data collected in this study. The rate constants of a reversible epimerization of kojibiose at pH 7.5 and 90 °C were (1.6 ± 0.1) × 10 -5 s -1 and (3.2 ± 0.2) × 10 -5 s -1 for the forward and reverse reactions, respectively, and were almost identical to those [(1.5 ± 0.1) × 10 -5 s -1 and (3.5 ± 0.4) × 10 -5 s -1 ] of sophorose. The rate constant of the decomposition reaction for kojibiose was (4.7 ± 1.1) × 10 -7 s -1 whereas that for sophorose [(3.7 ± 0.2) × 10 -6 s -1 ] was about ten times higher. The epimerization reaction was not significantly affected by the variation in the buffer except for a borate buffer, and depended instead upon the pH value (concentration of hydroxide ions), indicating that epimerization occurred as a function of the hydroxide ion. These instabilities are an extension of the neutral pH conditions for keto-enol tautomerization that are often observed under strong alkaline conditions., Competing Interests: There are no conflicts of interest to declare., (2019 by The Japanese Society of Applied Glycoscience.)

Acrylamide has neurotoxicity, carcinogenicity, and genotoxicity in experimental animals and cellular systems. Fried potato is one of the major intake sources of acrylamide in food, and fried onion was reported to contain up to 100 ng/g level of acrylamide. To determine acrylamide concentration in potato and onion stir-fried prior to boiling for simmered dishes such as curry, stew, and Niku-jaga, a typical Japanese meat/potato/onion cuisine, we collected samples stir-fried at homes of volunteers who intended voluntarily to cook these simmered dishes. Acrylamide level was analyzed by GC-MS after the xanthydrol derivatization. Among 53 stir-fried potato samples, median and average values of acrylamide were found to be 2.0 ng/g and 11 ng/g, respectively. Acrylamide levels of 27 samples (51%) were less than limit of detection (LOD) (4 ng/g), and those of 13 samples (25%) were less than limit of quantification (LOQ) (10 ng/g). In cases with less than LOD and less than LOQ of acrylamide levels, one-half of LOD and average of LOD and LOQ were adopted, respectively, to calculate the median and average. This median was markedly lower than those of fried potato (180 ng/g) and potato snacks including potato chips (550 ng/g) reported in monitoring in 2013 fiscal year in Japan. Among 58 stir-fried onion samples, acrylamide level of only one sample (2%) was less than LOD (3 ng/g), and those of 15 samples (26%) were less than LOQ (8 ng/g). The median and average values in the stir-fried onion were 14 ng/g and 36 ng/g, respectively. These values are comparable to those for stir-fried onion reported by Ministry of Agriculture, Forestry and Fisheries, Japan (median 19 ng/g, average 25 ng/g). But the maximum value of stir-fried onion 420 ng/g in the present study is much higher than the reported maximum value (70 ng/g)., Competing Interests: Conflict of interest statement: The authors had no conflict of interest to declare in this article., (©2017 Food Safety Commission, Cabinet Office, Government of Japan.)

This paper investigated acrylamide elution from roasted barley grain into mugicha and its formation during roasting of the grain. Mugicha is an infusion of roasted barley grains. Highly water-soluble acrylamide was easily extracted to mugicha from milled roasted barley grains in teabags. On the other hand, the acrylamide concentration in mugicha prepared from loose grain increased with longer simmering and steeping times. During roasting in a drum roaster, the acrylamide concentration of the grain increased as the surface temperature rose, reaching a maximum at 180-240°C. Above this temperature, the acrylamide concentration decreased with continued roasting, exhibiting an inverted 'U'-shaped curve. For most of the samples, the acrylamide concentration showed good correlation with the value of the colour space parameter L*. The dark-coloured roasted barley grains with lower L* values contained lower amounts of acrylamide as a result of deep roasting. The level of asparagine in barley grains was found to be a significant factor related to acrylamide formation in roasted barley products. The data are an important contribution to the mitigation of acrylamide intake from mugicha.

A method involving the use of doxorubicin-loaded polyethylene-glycol-modified liposomes and transfection using mannose-modified bubble lipoplexes in combination with ultrasound irradiation may be a promising approach to cancer treatment; it could not only suppress early-stage tumor growth but also enhance transfection efficacy in antigen-presenting cells, thus enhancing the therapeutic potential of a DNA vaccine. However, to date only limited research has been carried out regarding this combination DNA vaccination method for use in cancer therapy. In this study, we examined the anti-tumor effect of DNA vaccination using an ultrasound-responsive mannose-modified gene carrier combined with doxorubicin-encapsulated polyethylene-glycol-modified liposomes. Doxorubicin-encapsulated PEGylated liposomes activated transcriptional factors, such as nuclear factor-κB and AP-1 in the spleen; subsequently pUb-M, ubiquitylated melanoma-related antigen encoding plasmid DNA expression in splenic cells was significantly enhanced. Moreover, effective cytotoxic T-lymphocyte activities were stimulated by DNA vaccination combined with the administration of doxorubicin-encapsulated polyethylene-glycol-modified liposomes. Furthermore, potent DNA vaccine effects against established solid tumor and metastatic tumor derived from B16BL6 melanoma were observed. These results suggest that the combined use of DNA vaccination with doxorubicin-encapsulated polyethylene-glycol-modified liposomes could be an effective method for the treatment of melanoma using immunotherapy., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Development of an efficient small interfering RNA (siRNA) delivery method using non-viral carriers is necessary to determine potent therapeutic effects of RNA interference. Inflammatory responses induced by siRNA interaction with Toll-like receptors and retinoic-acid-inducible gene I protein/melanoma differentiation-associated gene 5 (RIG-I/MDA-5) are obstacles to the application of siRNAs in clinically. Here, we evaluated the effects on inflammatory responses by our siRNA delivery method using bubble lipoplexes with ultrasound (US) exposure in cultured macrophages. The effective gene suppression effects were obtained under low-toxic conditions in this siRNA transfer method. The interferon (IFN)-α after siRNA transfer using lipoplexes/bubble lipoplexes with US exposure was not detected. However, low levels of type I IFN mRNA production were induced through interaction of siRNA and cytoplasmic RIG-I/MDA-5, but not Toll-like receptors. Our findings indicate that it is possible to develop a safe and efficient siRNA delivery technique using mannosylated bubble lipoplexes and US exposure.

We investigated the presence of acrylamide in roasted barley grains, and assessed the correlation between acrylamide concentration and colour, and also examined acrylamide decrease during storage. Acrylamide concentrations in 45 commercially available roasted barley grains were analysed. The mean and standard deviation were 0.24 and 0.08 mg kg(-1), respectively. The CIE colour parameter a* value had little correlation with acrylamide concentration in roasted barley grains; however, the L* and b* values showed correlations with acrylamide concentration in the grains, yielding a correlation coefficient of 0.42 and 0.40, respectively. Darker-coloured roasted barley grains with lower L* values may contain lower amounts of acrylamide. Although acrylamide concentration decreased by 40% in the grains, and decreased by 36% in the milled grains (teabag form) after 309 days of storage at room temperature a significant difference in the rate of acrylamide decrease was not observed between the grain and teabag forms. The data obtained in this study are of importance to the risk assessment and management of acrylamide exposure in Japan.

Scabichelin and turgichelin, novel tris-hydroxamate siderophores, were isolated from Streptomyces antibioticus NBRC 13838/Streptomyces scabies JCM 7914 and Streptomyces turgidiscabies JCM 10429, respectively. The planar structures of scabichelin and turgichelin were elucidated by mass spectrometry, and 1- and 2-D NMR spectroscopic analyses of their gallium(III) complexes. The relative and absolute stereochemistry of the metabolites was determined by the modified Marfey's method in conjunction with computational modelling and NOESY NMR analysis of Ga-scabichelin and Ga-turgichelin. Genome sequence analysis of the plant pathogen Streptomyces scabies 87.22 identified a gene cluster containing a gene encoding a nonribosomal peptide synthetase (NRPS) that was predicted to direct the production of a pentapeptide with structural similarities to scabichelin and turgichelin. Comparative LC-MS/MS analyses of iron-deficient culture supernatants from wild type S. scabies 87.22 and a mutant in which the NRPS gene had been disrupted, and scabichelin purified from S. antibioticus, showed that scabichelin is the metabolic product of the cryptic gene cluster, strongly suggesting that it functions as a siderophore.

A new 16-membered macrolide named makinolide B (1) was isolated from Streptomyces sp. MK-19. The structure of makinolide B (1) was determined on the basis of 2D NMR experiments involving DQF-COSY, TOCSY, HSQC, and HMBC methods. Application of the paper disk diffusion method to makinolide B (1) showed weak antibacterial activity against Staphylococcus aureus at the dose of 100 µg/disk.

Unlabelled: Hepatitis is often associated with the overexpression of various adhesion molecules. In particular, intracellular adhesion molecule-1 (ICAM-1), which is expressed on hepatic endothelial cells (HECs) in the early stage of inflammation, is involved in serious illnesses. Therefore, ICAM-1 suppression in HECs enables the suppression of inflammatory responses. Here, we developed an ICAM-1 small interfering RNA (siRNA) transfer method using ultrasound (US)-responsive and mannose-modified liposome/ICAM-1 siRNA complexes (Man-PEG(2000) bubble lipoplexes [Man-PEG(2000) BLs]), and achieved efficient HEC-selective ICAM-1 siRNA delivery in combination with US exposure. Moreover, the sufficient ICAM-1 suppression effects were obtained via this ICAM-1 siRNA transfer in vitro and in vivo, and potent anti-inflammatory effects were observed in various types of inflammation, such as lipopolysaccharide, dimethylnitrosamine, carbon tetrachloride, and ischemia/reperfusion-induced inflammatory mouse models., Conclusion: HEC-selective and efficient ICAM-1 siRNA delivery using Man-PEG(2000) BLs and US exposure enables suppression of various types of acute hepatic inflammation. This novel siRNA delivery method may offer a valuable system for medical treatment where the targeted cells are HECs., (Copyright © 2012 American Association for the Study of Liver Diseases.)

Flavonoids accumulated in proanthocyanidin-free near-isogenic lines iso ant 13, iso ant 17, and iso ant 22 of Nishinohoshi, developed by backcross breeding using a leading cultivar, Nishinohoshi, as a recurrent parent and a proanthocyanidin-free mutant as a nonrecurrent parent in Japan, were examined. A new flavanone, (2RS)-dihydrotricin 7-O-β-D-glucopyranoside (1), known flavanones (2RS)-dihydrotricin (2) and (2RS)-homoeriodictyol (3), and known flavones chrysoeriol 7-O-[α-L-rhamnopyranosyl-(1→6)-β-D-glucopyranoside] (4), chrysoeriol 7-O-β-D-glucopyranoside (5), tricin (6), and chrysoeriol (7) were isolated from iso ant 17 of Nishinohoshi. The structures and stereochemistries of the isolated flavonoids (1-7) were elucidated on the basis of spectroscopic analyses. The concentrations of the isolated flavonoids (1-7) in iso ant 13, iso ant 17, and iso ant 22 of Nishinohoshi were similar to each other, whereas the flavonoids 1-5 and 7 were not detected in Nishinohoshi, an old Japanese cultivar, Amaginijo, and North American cultivar Harrington. The concentration of tricin (6) in Nishinohoshi was a half those in iso ant 13, iso ant 17, and iso ant 22 of Nishinohoshi. Except for iso ant 13, iso ant 17, and iso ant 22 of Nishinohoshi, the concentration of tricin (6) was highest in Nishinohoshi, followed by Amaginijo and Harrington. Thus, tricin (6), its precursor dihydrotricin (2), and its glucopyranoside, dihydrotricin 7-O-β-D-glucopyranoside (1), as well as chrysoeriol (7) and homoeriodictyol (3) were accumulated in iso ant 13, iso ant 17, and iso ant 22 of Nishinohoshi probably by blocking at the step of flavanone 3-hydroxylase in the procyanidin biogenetic pathway, resulting in enhancement of the alternative biogenetic pathway.

We report a case of sporadic gastric carcinoid tumor successfully treated by two-stage laparoscopic surgery. A 38-year old asymptomatic woman was referred to our hospital for evaluation of a submucosal tumor of the stomach. Endoscopic examination showed a solitary submucosal tumor without ulceration or central depression on the posterior wall of the antrum and biopsy specimens were not sufficient to determine the diagnosis. Endoscopic ultrasound revealed a tumor nearly 2 cm in diameter arising from the muscle layer and a computed tomography scan showed the tumor enhanced in the arterial phase. Laparoscopic wedge resection was performed for definitive diagnosis. Pathologically, the tumor was shown to be gastric carcinoid infiltrating the muscle layer which indicated the probability of lymph node metastasis. Serum gastrin levels were normal. As a radical treatment, laparoscopy-assisted distal gastrectomy with regional lymphadenectomy was performed 3 wk after the initial surgery. Finally, pathological examination revealed no lymph node metastasis.

This case report describes the orthodontic treatment of an 18-year-old female patient with Class II malocclusion with dentoskeletal bimaxillary protrusion. An acceptable treatment result was obtained with a four first premolar extraction and an additional maxillary two second molar extraction plan. Standard edgewise appliances were placed after the premolars were extracted. A positive soft tissue response to treatment was achieved, and the patient's profile was improved, with a reduction of lip protrusion and mentalis strain. Dentally, the interincisal angle improved significantly as both the maxillary and mandibular incisors were uprighted after space closure. The occlusion remained stable during 2 years of follow-up.

Bitter gourd ( Momordica charantia L.) pericarp, placenta, and seed extracts were previously shown to induce apoptosis in HL60 human leukemia cells. To determine the active component that induces apoptosis in cancer cells, bitter gourd ethanol extract was fractionated by liquid-liquid partition and silica gel column chromatography. Several fractions obtained by silica gel column chromatography inhibited growth and induced apoptosis in HL60 cells. Among them, fraction 7 had the strongest activity in inhibiting growth and inducing apoptosis in HL60 cells. A component that induced apoptosis in HL60 cells was then isolated from fraction 7 by another silica gel column chromatography and high-performance liquid chromatography (HPLC) using a C18 column and was identified as (9Z,11E,13E)-15,16-dihydroxy-9,11,13-octadecatrienoic acid (15,16-dihydroxy alpha-eleostearic acid). 15,16-Dihydroxy alpha-eleostearic acid induced apoptosis in HL60 cells within 5 h at a concentration of 160 microM (50 microg/mL). (9Z,11E,13E)-9,11,13-Octadecatrienoic acid (alpha-eleostearic acid) is known to be the major conjugated linolenic acid in bitter gourd seeds. Therefore, the effect of alpha-eleostearic acid on the growth of some cancer and normal cell lines was examined. alpha-Eleostearic acid strongly inhibited the growth of some cancer and fibroblast cell lines, including those of HL60 leukemia and HT29 colon carcinoma. alpha-Eleostearic acid induced apoptosis in HL60 cells after a 24 h incubation at a concentration of 5 microM. Thus, alpha-eleostearic acid and the dihydroxy derivative from bitter gourd were suggested to be the major inducers of apoptosis in HL60 cells.

The movement of cellular water accompanies changes in growth within dormant buds. To further understand this process, accumulation of tonoplast deltaTIP1 and plasma membrane PIP2 aquaporin transcripts was measured by quantitative reverse transcriptase-polymerase chain reaction and the water dynamics in dormant peach (Prunus persica L.) flower buds was studied by magnetic resonance imaging. Proton density (PD), spin-spin relaxation time (T(2)) and apparent diffusion coefficient (ADC) were used to observe water dynamics during dormancy. The expression of deltaTIP1 and PIP2 aquaporins, PD and T(2) in the upper part of the bud including primordia, in the basal part of the bud and the bud trace increased earlier in the low-chill cultivar 'Coral' than in the high-chill cultivar 'Kansuke Hakuto,' reflecting the difference in timing for the end of endodormancy in the two cultivars. deltaTIP1 mRNA accumulated mainly in the basal part of the bud, whereas PIP2 mRNA was detected mainly in the upper part. These findings may reflect the activation of inter- and intracell communication through membrane transport properties of aquaporins resulting in a gradual increase in water content to that required for bud activity at the end of endodormancy. An apparent decrease in the expression of deltaTIP1 and PIP2 mRNAs was, however, observed in late winter in some portions of the buds of both cultivars just before sprouting.

Bitter gourd ( Momordica charantia L.) is a popular tropical vegetable in Asian countries. Previously it was shown that bitter gourd placenta extract suppressed lipopolysaccharide (LPS)-induced TNFalpha production in RAW 264.7 macrophage-like cells. Here it is shown that the butanol-soluble fraction of bitter gourd placenta extract strongly suppresses LPS-induced TNFalpha production in RAW 264.7 cells. Gene expression analysis using a fibrous DNA microarray showed that the bitter gourd butanol fraction suppressed expression of various LPS-induced inflammatory genes, such as those for TNF, IL1alpha, IL1beta, G1p2, and Ccl5. The butanol fraction significantly suppressed NFkappaB DNA binding activity and phosphorylation of p38, JNK, and ERK MAPKs. Components in the active fraction from bitter gourd were identified as 1-alpha-linolenoyl-lysophosphatidylcholine (LPC), 2-alpha-linolenoyl-LPC, 1-lynoleoyl-LPC, and 2-linoleoyl-LPC. Purified 1-alpha-linolenoyl-LPC and 1-linoleoyl-LPC suppressed the LPS-induced TNFalpha production of RAW 264.7 cells at a concentration of 10 microg/mL.

We have presented a systematic experimental investigation of carboxyl oxygen electric-field-gradient (EFG) and chemical shielding (CS) tensors in crystalline amino acids. Three 17O-enriched amino acids were prepared: L-aspartic acid, L-threonine, and L-tyrosine. Analysis of two-dimensional 17O multiple-quantum magic-angle spinning (MQMAS), MAS, and stationary NMR spectra yields the 17O CS, EFG tensors and the relative orientations between the two tensors for the amino acids. The values of quadrupolar coupling constants (CQ) are found to be in the range of 6.70-7.60 MHz. The values of deltaiso lie in the range of 268-292 ppm, while those of the delta11 and delta22 components vary from 428 to 502 ppm, and from 303 to 338 ppm, respectively. There is a significant correlation between the magnitudes of delta22 components and C--O bond lengths. Since C--O bond length may be related to hydrogen-bonding environments, solid-state 17O NMR has significant potential to provide insights into important aspects of hydrogen bonds in biological systems., (Copyright (c) 2007 John Wiley & Sons, Ltd.)

Optimization of the solid-phase extraction cleanup procedure enabled the GC-MS analysis of acrylamide in tea samples without the interference of bromination by tea catechins. Although polyvinylpolypyrrolidone (PVPP) is available for removing tea catechins from tea extract, the peaks derived from PVPP had the same retention time as brominated acrylamide in mass chromatograms obtained by GC-MS. A considerable amount of acrylamide was formed at roasting temperatures of > or =120 degrees C; the highest acrylamide level was observed when tea samples were roasted at 180 degrees C for 10 min. Higher temperatures and longer processing times caused a decrease in the acrylamide content. Furthermore, an analysis of 82 tea samples showed that rather than the reducing sugar content, the asparagine content in tea leaves was a significant factor related to acrylamide formation in roasted products. The acrylamide level in roasted tea products was controlled by asparagine in the presence of reducing sugars.

The structure and stability of hydrogen bonds in alpha-chitin were investigated by (13)C solid-state NMR measurements at different temperatures. Splitting of the carbonyl carbon signal for alpha-chitin was interpreted as two types of hydrogen bonding; the peaks at 173.5 and 175.8 ppm were assigned, respectively, to a carbonyl carbon hydrogen bonded exclusively to the NH group and a carbonyl carbon hydrogen-bonded to both NH and C(6)-OH groups. Approximately 60% of carbonyl groups exclusively contributed to the intermolecular hydrogen bonding and ca. 40% of them to the combination of intermolecular and intramolecular hydrogen bonding. Internal rotation around the C(5)-C(6) bond was detected at 55 degrees C.

Acrylamide concentrations in processed foods sold in Japanese markets were analyzed by LC-MS/MS and GC-MS methods. Most potato chips and whole potato-based fried snacks showed acrylamide concentration higher than 1000 microg/kg. The concentrations in non-whole potato based Japanese snacks, including rice crackers and candied sweet potatoes, were less tha. 350 microg/kg. Those in instant precooked noodles were less than 100 microg/kg with only one exception. The effect of storage condition of potato tubers on acrylamide concentration in potato chips after frying was also investigated. Sugar content in the tubers increased during cold storage, and the acrylamide concentration increased accordingly. The concentrations of asparagine and other amino acids, however, did not change during the cold storage. High correlations were observed between the acrylamide content in the chips and glucose and fructose contents in the tubers. This fact indicated that the limiting factor for acrylamide formation in potato chips is reducing sugar, not asparagine content in the tubers. Effects of roasting time and temperature on acrylamide concentration in roasted green tea are also described.

Nagkesar (buds of Mammea longifolia) is extensively used in culinary preparations especially in spice blend in India. Previously thirteen compounds were identified from the medium polar fractions of methanol extract of buds of M. longifolia. In continuation of the study, the polar fraction of methanol extract exhibited stronger antioxidative and radical scavenging activities. An attempt was made to separate and identify the active compounds and found that those were proanthocyanidin oligomers with mean degree of polymerisation ranges from 2 to 10. This is the first report to indicate that Mammea buds contain antioxidant and radical scavenging procyanidin oligomers.

Ethyl esters and phosphatidylcholines (PCs) of polyunsaturated fatty acids (PUFAs) were oxidized in organic solvents, aqueous emulsions, and liposomes in the presence of a radical inducer. Oxidation products and the positional distribution of monohydroperoxide (MHP) were determined by gas chromatography-mass spectrometry (GC-MS) analysis. The total amount of the oxidation products, of PUFA ethyl esters and PCs in organic solvents, increased with an increase in the number of bis-allylic positions. However, the opposite results were obtained in an aqueous emulsion and liposomes. The distribution pattern of MHPs obtained from oxidation of the linolate and alpha-linolenate showed little difference between a chloroform solution and an aqueous emulsion or liposomes. However, there were differences between these systems with the arachidonate, the icosapentaenoate, and docosahexaenoate. These results may be due to the different rate of hydrogen abstraction from bis-allylic positions in the fatty acid moieties, and/or 1,3-cyclization of hydroperoxides in the systems.

An inulin fructotransferase producing difructose dianhydride I (EC 2.4.1.200) was purified from Arthrobacter ureafaciens A51-1. It had maximum activity at pH 5.5 and 45 degrees C, and was stable up to 80 degrees C. This is the highest thermal stability for this enzyme reported to date. The molecular mass was estimated to be 38000 by SDS-PAGE, and 61000 by gel filtration. It was therefore estimated to be a dimer.

Five caffeic acid derivatives were found in the roots of yacon, Smallanthus sonchifolius (Poepp. and Endl.) H. Robinson, Asteraceae, as the major water-soluble phenolic compounds. The structures of these compounds were determined by analysis of spectroscopic data. Two of these were chlorogenic acid (3-caffeoylquinic acid) and 3,5-dicaffeoylquinic acid, common phenolic compounds in plants of the family Asteraceae. Three were esters of caffeic acid with the hydroxy groups of aldaric acid, derived from hexose. The structure of the aldaric moiety was determined by hydrolysis and comparison of NMR spectra with those of standard aldaric acids. The compounds were novel caffeic acid esters of altraric acid: 2,4- or 3,5-dicaffeoylaltraric acid, 2,5-dicaffeoylaltraric acid, and 2,3,5- or 2,4,5-tricaffeoylaltraric acid.