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Sanshool compounds are the trigeminal active compounds in andaliman (Zanthoxylum acantho-podium DC) with a numbing and tingling sensation. The analysis of such compounds is usually done through HPLC approach; however, limited studies have reported that the analysis of such compounds could be conducted with Gas Chromatography-Mass Spectrometry (GC-MS). This method could save research time and funding by analyzing both sanshools and volatiles simultaneously, which would describe the complete profile of andaliman flavor compounds. This study aimed to confirm the potency of GC-MS in analyzing sanshool compounds and to utilize this method in studying the impact of different drying methods towards andaliman trigeminal active compounds. Andaliman was dried with five drying methods (sun, sunshade, air, oven, and freeze-drying) and was macerated with chloroform, concentrated, and analyzed with GC-MS. The results of this study showed that GC-MS was able to analyze sanshool compounds efficiently. Drying had no statistically significant impact on sanshool quantities extracted from andaliman. Fresh andaliman contained 0.69 % (dry weight basis) of α-sanshool, the main sanshool in andaliman. On the other hand, dried andaliman contained 0.80-1.08% of α-sanshool (dry weight basis). As oven drying managed to produce andaliman with a similar concentration of α-sanshool at a faster time and more affordable cost than other drying methods, oven drying was suggested as the ideal drying method to extend the shelf life of andaliman.

Cereal crop production is severely affected by seed-borne bacterial diseases across the world. Locally occurring disease resistance in various crops remains elusive. Here, we have observed that rice plants of the same cultivar can be differentiated into disease-resistant and susceptible phenotypes under the same pathogen pressure. Following the identification of a seed-endophytic bacterium as the resistance-conferring agent, integration of high-throughput data, gene mutagenesis and molecular interaction assays facilitated the discovery of the underlying mode of action. Sphingomonas melonis that is accumulated and transmitted across generations in disease-resistant rice seeds confers resistance to disease-susceptible phenotypes by producing anthranilic acid. Without affecting cell growth, anthranilic acid interferes with the sigma factor RpoS of the seed-borne pathogen Burkholderia plantarii, probably leading to impairment of upstream cascades that are required for virulence factor biosynthesis. The overall findings highlight the hidden role of seed endophytes in the phytopathology paradigm of 'disease triangles', which encompass the plant, pathogens and environmental conditions. These insights are potentially exploitable for modern crop cultivation threatened by globally widespread bacterial diseases.

Eucalypts are important forest resources in southwestern China, and may be tolerant to elevated ground-level ozone (O3) concentrations that can negatively affect plant growth. High CO2 may offset O3-induced effects by providing excess carbon to produce secondary metabolites or by inducing stomatal closure. Here, the effects of elevated CO2 and O3 on leaf secondary metabolites and other defense chemicals were studied by exposing seedlings of Eucalyptus globulus, E. grandis, and E. camaldulensis × E. deglupta to a factorial combination of two levels of O3 (−1 and 60 nmol mol−1) and CO2 (ambient: 370 μmol mol−1 and 600 μmol mol−1) in open-top field chambers. GC-profiles of leaf extracts illustrated the effect of elevated O3 and the countering effect of high CO2 on compounds in leaf epicuticular wax and essential oils, i.e., n-icosane, geranyl acetate and elixene, compounds known as a first-line defense against insect herbivores. n-Icosane may be involved in tolerance mechanisms of E. grandis and the hybrid, while geranyl acetate and elixene in the tolerance of E. globulus. Elevated O3 and CO2, singly or in combination, affected only leaf physiology but not biomass of various organs. Elevated CO2 impacted several leaf traits, including stomatal conductance, leaf mass per area, carbon, lignin, n-icosane, geranyl acetate and elixene. Limited effects of elevated O3 on leaf physiology (nitrogen, n-icosane, geranyl acetate, elixene) were commonly offset by elevated CO2. We conclude that E. globulus, E. grandis and the hybrid were tolerant to these O3 and CO2 treatments, and n-icosane, geranyl acetate and elixene may be major players in tolerance mechanisms of the tested species.

Quercetin, a flavonol, is a functional compound that is abundant in onions and is known to have antioxidant and anti-inflammatory effects. Quercetin and its glucoside are known to function as peroxisome proliferator-activated receptor (PPAR) ligands and showed high PPAR-α transactivation activity but little PPAR-γ transactivation activity in some reports. In this study, we demonstrated that an aqueous extract of a quercetin-rich onion cultivar increased transactivation activities not only of PPAR-α but also of PPAR-γ. We isolated (9S,12S,13S)-(10E)-9,12,13-trihydroxyoctadec-10-enoic acid (pinellic acid) obtained from the aqueous extract using PPAR-γ transactivation as an index. Furthermore, it was revealed that pinellic acid could transactivate PPAR-α. Our findings are the first report mentioned showing that trihydroxyoctadec-10-enoic acids showed PPAR-α/γ transactivation activities.

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The extracellular signaling molecule indole plays a pivotal role in biofilm formation by the enteric gammaproteobacterium Escherichia coli; this process is particularly correlated with the extracellular indole concentration. Using the indole-biodegrading betaproteobacterium Burkholderia unamae, we examined the mechanism by which these two bacteria modulate biofilm formation in an indole-dependent manner. We quantified the spatial organization of cocultured microbial communities at the micrometer scale through computational image analysis, ultimately identifying how bidirectional cell-to-cell communication modulated the physical relationships between them. Further analysis allowed us to determine the mechanism by which the B. unamae-derived signaling diketopiperazine cyclo(Pro-Tyr) considerably upregulated indole biosynthesis and enhanced E. coli biofilm formation. We also determined that the presence of unmetabolized indole enhanced the production of cyclo(Pro-Tyr). Thus, bidirectional cell-to-cell communication that occurred via interspecies signaling molecules modulated the formation of a mixed-species biofilm between indole-producing and indole-consuming species. IMPORTANCE Indole is a relatively stable N-heterocyclic aromatic compound that is widely found in nature. To date, the correlations between indole-related bidirectional cell-to-cell communications and interspecies communal organization remain poorly understood. In this study, we used an experimental model, which consisted of indole-producing and indole-degrading bacteria, to evaluate how bidirectional cell-to-cell communication modulated interspecies biofilm formation via intrinsic and environmental cues. We identified a unique spatial patterning of indole-producing and indole-degrading bacteria within mixed-species biofilms. This spatial patterning was an active process mediated by bidirectional physicochemical interactions. Our findings represent an important step in gaining a more thorough understanding of the process of polymicrobial biofilm formation and advance the possibility of using indole-degrading bacteria to address biofilm-related health and industry issues.

A chiral N-protected alpha-amino acid N-hydroxysuccinimide ester (OSu) is a common useful reagent for peptide bond formation. Recently, N-trifluoroacetyl (TFA) alpha-amino acid OSu esters have been reported as acyl donors for Frieldel-Crafts reactions to synthesize chiral alpha-amino phenyl ketones retaining the configurations of the starting alpha-amino acids. There are few reports for chiral TFA protected methionine, which has methylthioethyl structure in the side-chain of the alpha-amino acid. The detailed synthesis of chiral TFA-Met-OSu and its application as an acyl donor for Friedel-Crafts acylation is reported.

Conifer resins are used as chemical raw materials for daily necessities. There have been many reports on the aroma components of turpentine oil from rosin, but there has been no reports on fluctuations in the aroma components through spring to late autumn. We speculated that the aroma components in the essential oils of deciduous coniferous larches might fluctuate during maturation of the foliage. In this study, we focused on the aroma components of larch essential oils and we clarified by multivariate analysis how the aroma components fluctuate during leaf maturation. The results of analysis showed that there was a drastic seasonal fluctuation of the chemical components in larch essential oils, especially in senescent leaves in late autumn. Cryptone and linalool were identified as the characteristic aroma components in essential oil from senescent larch leaves.

Summary • In a coinoculation test of seed-epiphytic Penicillium species and pathogenic Pythium vexans to Picea glehnii seedlings, the number of surviving seedlings which were inoculated with P. vexans 5 d after preinoculation with Penicillium damascenum PGS-O7 increased compared with those inoculated with P. vexans alone. • The phytotoxicity of antifungal compounds to P. glehnii seeds and seedlings was assessed in growth experiments. Production of these compounds was quantitatively analysed in the rhizosphere of the host seedlings using chromatography techniques. • Dense mycelial growth of P. damascenum was observed microscopically around the roots of the inoculated seedlings. Furthermore, the antifungal and phytotoxic compound citrinin produced by P. damascenum was detected as a component released around the roots of the normally growing fungus-inoculated seedlings. • We propose two possible mechanisms for the protection of P. glehnii seedlings by P. damascenum from P. vexans; first, chemical protection by an antibiotic agent, citrinin produced by P. damascenum, and second, the occupation of the space around the P. glehnii roots by the P. damascenum mycelia.

Symbiosis of Penicillium rolfsii Y-1 is essential for the seed germination of Hawaii yellow-eyed grass (Xyris complanata). However, the local soil where the plants grow naturally often suppresses the radicle growth of the seedlings. This radicle growth was drastically restored by coinoculation of Paraburkholderia phenazinium isolate CK-PC1, which is a rhizobacterium of X. complanata. It was found that the isolate CK-PC1 produced phenazine-1-carboxylic acid (PCA, 1) as a major metabolite. The biological effects of PCA (1) were investigated using the seeds of X. complanata and Mung bean (Vigna radiata) and it was uncovered that the symbiosis of the isolate CK-PC1was essential for the postgermination growth of X. complanata and the metabolite PCA (1) might partially contribute to promote the growth of the plants.

1-kestose (O-β-D-fructofuranosyl-(2→1)-β-D-fructofuranosyl-(2→1)-α-D-glucopyranoside) is a potential short chain fructooligosaccharide with an inulin-type skeleton. Halogenation of 1-kestose was conducted via the Appel reaction with the use of carbon tetrahalide (CBr4 or CCl4) and triphenylphosphine, which was then followed by conventional acetylation. The per-O-acetylated form of 6,6’,6’’-trihalogenated derivatives of 1- kestose were conveniently isolated. Further deprotection of the per-O-acetylated form resulted in 6-, 6’-, and 6’’-trihalogenated derivatives. The structure elucidation by one- and two-dimensional nuclear magnetic resonance established that halogenations are specific at the 6-, 6’-, and 6’’-position of 1-kestose primary alcohols.

Sucrose is well known as naturally occurring sweeteners. Photoreactive sucrose derivative containing 3-(trifluoromethyl) diazirinyl moiety is designed for photoaffinity labeling. As 1'-hydroxyl group of sucrose is well known to be less reactive than other primary alcohols, the optimization of reaction conditions for diazirinyl benzyl bromide derivative at sucrose 1'-postion was examined to elucidate the functional analysis of sweet receptors.

Phenylthiourea (PTU) is well known as bioactive compound and one of the reversible inhibitors for tyrosinase. Tyrosinase plays very important roles for tyrosine metabolisms to maintain the skin homeostasis from sunlight with forming melanin. Synthesis of photoaffinity label reagents of PTU will be attractive thesis to elucidate functional analysis for tyrosinase.

Conifer resins are used as chemical raw materials for daily necessities. There have been many reports on the aroma components of turpentine oil from rosin, but there has been no reports on fluctuations in the aroma components through spring to late autumn. We speculated that the aroma components in the essential oils of deciduous coniferous larches might fluctuate during maturation of the foliage. In this study, we focused on the aroma components of larch essential oils and we clarified by multivariate analysis how the aroma components fluctuate during leaf maturation. The results of analysis showed that there was a drastic seasonal fluctuation of the chemical components in larch essential oils, especially in senescent leaves in late autumn. Cryptone and linalool were identified as the characteristic aroma components in essential oil from senescent larch leaves.

Nitrous oxide (N2O) emission-suppressing activity of some electron-transport inhibitors of the Hill reaction system was investigated. The Hill reaction inhibitors&mdash, paraquat, isouron, bromacil, diquat, and simazine&mdash, all of which have been or are currently being used as herbicides in farming activity are expected to inhibit the electron-transporting pathways of nitrate respiration in denitrifying bacteria. Using N2O-emitting soil bed (5.0 g of fresh weight) from a continuously manured Andisol corn farmland in Hokkaido, Japan, which was autoclaved and further supplemented with an active N2O-emitter, Pseudomonas sp. 5CFM15-6D, and 1 mL of 100 mM NH4NO3 or (NH4)2SO4 solution as the sole nitrogen source (final concentration, 0.2 mM) in a 30 mL gas-chromatography vial, the effects of the five herbicides on N2O emission were examined. Paraquat and isouron (each at 50 &micro, M) showed a statistically significant suppression of N2O emission in both the nitrification and the denitrification processes after a 7-day-incubation, whereas diquat at the same concentration accelerated N2O emission in the presence of NO3&minus, These results suggest that paraquat and isouron inhibited both the nitrification and the denitrification processes for N2O generation, or its upstream stages, whereas diquat specifically inhibited N2O reductase, an enzyme that catalyzes the reduction of N2O to N2 gas. Incomplete denitrifiers are the key players in the potent emission of N2O from Andisol corn farmland soil because of the missing nosZ gene. The electron relay system-inhibiting herbicides&mdash, paraquat and isouron&mdash, possibly contribute to the prevention of denitrification-induced nitrogen loss from the farming soil.

Coralloid roots are specialized tissues of cycads (Cycas revoluta) that are involved in symbioses with nitrogen-fixing Nostoc cyanobacteria. We found that a crude methanolic extract of coralloid roots induced differentiation of the filamentous cell aggregates of Nostoc species into motile hormogonia. Hence, the hormogonium-inducing factor (HIF) was chased using bioassay-based isolation, and the active principle was characterized as a mixture of diacylglycerols (DAGs), mainly composed of 1-palmitoyl-2-linoleoyl-sn-glycerol (1), 1-palmitoyl-2-oleoyl-sn-glycerol (2), 1-stearoyl-2-linolenoyl-sn-glycerol (3), and 1-stearoyl-2-linoleoyl-sn-glycerol (4). Enantioselectively synthesised compound 1 showed a clear HIF activity at 1 nmol (0.6 µg) disc−1 for the filamentous cells, whereas synthesised 2-linoleoyl-3-palmitoyl-sn-glycerol (1′) and 1-palmitoyl-2-linoleoyl-rac-glycerol (1/1′) were less active than 1. Conversely, synthesised 1-linoleoyl-2-palmitoyl-rac-glycerol (8/8′) which is an acyl positional isomer of compound 1 was inactive. In addition, neither 1-monoacylglycerols nor phospholipids structurally related to 1 showed HIF-like activities. As DAGs are protein kinase C (PKC) activators, 12-O-tetradecanoylphorbol-13-acetate (12), urushiol C15:3-Δ10,13,16 (13), and a skin irritant anacardic acid C15:1-Δ8 (14) were also examined for HIF-like activities toward the Nostoc cells. Neither 12 nor 13 showed HIF-like activities, whereas 14 showed an HIF-like activity at 1 nmol/disc. These findings appear to indicate that some DAGs act as hormogonium-inducing signal molecules for filamentous Nostoc cyanobacteria.

A cosolvent-promoted O-benzylation strategy with Ag2O was developed. The cosolvent consisting of CH2Cl2 and n-hexane can not only improve the reaction solubility for carbohydrates but also increase the benzylation efficiency. The formation of byproducts is greatly inhibited in the developed method. This method is simple, mild, and highly effective, and numerous 1'-benzylated sucrose derivatives were prepared including a photoreactive (trifluoromethyl)phenyldiazirine-based sucrose. The mechanisms of benzylation with primary and secondary benzyl bromides were also elaborated. Furthermore, the application scope with alcohols, glucose, and ribose derivatives was investigated.

5-Nitro-2-propoxyaniline is one of the strongest artificial sweeteners. However, little is known about the detailed relationship of the structure and biological activity between 5-nitro-2-propoxyaniline and its sweet receptor. Photoaffinity labeling is a useful method for revealing interactions of a small bioactive compound with molecules. Therefore, we synthesized photoreactive 2-propoxyaniline derivatives as useful tools for revealing the interactions by photoaffinity labeling.

Plant hormones are a group of structurally diverse small compounds that orchestrate the cellular processes governing proper plant growth and environmental adaptation. To understand the details of hormonal activity, we must study not only their inherent activities but also the cross-talk among plant hormones. In addition to their use in agriculture, plant chemical activators, such as probenazole and uniconazole, have made great contributions to understand hormonal cross-talk. However, the use of plant chemical activators is limited due to the lack of activators for certain hormones. For example, to the best of our knowledge, there are only a few chemical activators previously known to stimulate the accumulation of ABA in plants, such as absinazoles and proanthocyanidins. In many cases, antagonistic effects have been examined in experiments using exogenously applied ABA, although these studies did not account for biologically relevant concentrations. In this report, it was found that a natural product, theobroxide, had potential as a plant chemical activator for stimulating the accumulation of ABA. Using theobroxide, the antagonistic effect of ABA against GAs was proved without exogenously applying ABA or using mutant plants. Our results suggest that ABA levels could be chemically controlled to elicit ABA-dependent biological phenomena.

Dent corn Andisol at the Hokkaido University Shizunai Livestock Experimental Farm actively emits nitrous oxide (N2O). In order to screen for culturable and active N2O emitters with high N2O emission potential, soft gel medium containing excess KNO3 was inoculated with soil suspensions from farm soil samples collected at different land managements. Dominant bacterial colonies were searched for among 20 of the actively N2O-emitting cultures from post-harvest soil and 19 from pre-tilled soil, and all isolates were subjected to the culture-based N2O emission assay. Ten active N2O-emitting bacteria, four from post-harvest soil and six from pre-tilled soil, out of 156 isolates were identified as genus Pseudomonas by 16S rRNA gene sequencing. These N2O emitters showed clear responses to NO3(-) within a neutral pH range (5.5-6.7), and accelerated N2O production with 1.5-15 mM sucrose supplementation, suggesting the production of N2O during the denitrification process. However, the negative responses of 6 active N2O emitters, 3 from post-harvest soil and 3 from pre-tilled soil, out of the 10 isolates in the acetylene-blocking assay suggest that these 6 N2O emitters are incomplete denitrifiers that have lost their N2O reductase (N2OR) activity. Although the PCR assay for the denitrification-associated genes, narG and nirK/S, was positive in all 10 Pseudomonas isolates, those negative in the acetylene-blocking assay were nosZ-negative. Therefore, these results imply that the high N2O emission potential of dent corn Andisol is partly attributed to saprophytic, nosZ gene-missing pseudomonad denitrifiers.

Regioselective halogenations of sucrose primary alcohols can simplify the synthesis of carbohydrate-based products. The Appel reaction, using carbon tetrahalide (CBr4 or CCl4) and triphenylphosphine, offers efficient conversion of primary hydroxyl groups to halide. Previous halogenation of sucrose with limited amounts of Appel reagent gave obscure result-regarding the halogenation selectivity of sucrose primary alcohols at 6-and 6'-position. Within careful purification of its per-O-acetylated form, re-subjection of sucrose into Appel reaction resulted in two mono-and one dihalogenated products only at 6-and/or 6'-position. Extensive NMR analyses support the revision of previous literature's assignments. Comprehensive analysis of each monohalogenated sucrose at the primary position, including the first reported 1'-monohalogenated sucrose derivatives synthesis via regioselective enzymic deacetylation, provided halogenation of sucrose primary alcohols by the Appel reaction followed the order of 6> 6'>> 1'.

An interaction between two different living creatures is often mediated by a chemical substance, along with metabolic or morphological differentiation. Such phenomenon-based investigation of chemical substances sometimes leads to the discovery of a novel signaling substance associated with biological pest control, including pinpoint regulation of fundamental metabolisms. In studies on the metabolic regulation of denitrifying bacteria and phytopathogenic microorganisms, such chemicals linked to the introduction of new ideas and unique approaches for biorational pest controls are described.

To establish a sensitive bioassay for Nostocean hormogonium induction, we compared the effectiveness of the morpho-differentiation induction on two gelled plates, agar and gellan gum, for anacardic acid C15:1-Δ8 decyl ester (1) (100 nmol/disc). On BG-110 (nitrogen-free) medium-based 0.6 and 0.8% agar plates, Nostoc sp. strain Yaku-1 isolated from a coralloid root of Cycas revoluta in Yakushima Island showed clear morpho-differentiation from filamentous aggregates into hormogonia, and the induced hormogonia dispersed within 24 h; however, similar hormogonium formation was not observed at agar concentrations of 1.0% or higher. Conversely, hormogonium induction was considerably more pronounced on gellan gum plates than those on agar plates through concentrations ranging from 0.6 to 1.6% even after 12 h of incubation, particularly active on the 0.8–1.0% gellan gum plates. Thus, gellan gum plates can achieve clear results within 12 h and are thus highly useful for primary screening for hormogonium-inducing factors (HIFs).

Archaeal communities in mineral soils were compared between a boreal forest in Finland and cold-temperate forest in Japan using 16S rRNA gene-targeted high-throughput sequencing. In boreal soils, Thaumarchaeota Group 1.1c archaea predominated and Thaumarchaeota Group 1.1a-associated and Group 1.1b archaea were also detected. In temperate soils, Thaumarchaeota Group 1.1a-associated and Group 1.1b archaea were dominant members at the subsurface, whereas their dominancy was replaced by Thermoplasmata archaea at the subsoil. An analysis of the ammonia monooxygenase subunit A gene of Archaea also indicated the distribution of Thaumarchaeota Group 1.1a-associated and Group 1.1b archaea in these soils.

Synthesis of cross-linkable diketopiperadine derivatives is described. Cross-linkable a-amino acid methyl esters were subjected to peptide synthesis with Boc-protected glycine or L-tyrosine. No protection of cross-linkable functional groups (catechol and phenylazide) is necessary for the construction of diketopiperazine skeleton.

Saccharin is one of the most common artificial sweeteners that has a bitter taste at high concentrations. Currently, there are no detailed functional analyses of these gustatory receptors. Therefore, we designed and synthesized photoreactive saccharin derivatives that contain a (trifluoromethyl)diazirinyl moiety at the 5- or 6-position for use as functional analysis tools for photoaffinity labeling.