Irciniaplysins A-D: New Psammaplysin Derivatives from Philippine Marine Sponge Ircinia sp.

Four new psammaplysin derivatives (1-4) with fatty acyl substituents, designated irciniaplysins A-D, and three known psammaplysins (5-7) were isolated from a marine sponge Ircinia sp. Their structures were elucidated using extensive spectroscopic analyses. The positions of the double bonds and the branch points of the fatty acyl side chains were determined by GC-MS analysis of their fatty acid methyl ester (FAME) derivatives. Irciniaplysins A (1) and B (2) contained an unusual long-chain fatty acyl substituent with a 5,9-diene unit. The isolated compounds were evaluated for their cytotoxic activity against the human colorectal carcinoma (HCT 116) cells, however, none of these compounds showed significant activity.

Role of trisaccharides in larval secretion of Lycaeides argyrognomon butterfly on ant attendance.

Several myrmecophilous insects participate in symbiotic relationships with ants that receive sugar-rich food rewards. For instance, certain aphid species secrete honeydew containing high concentration of melezitose, which acts as a potent feeding-stimulant and attractant for ants. Lycaenid butterfly larvae possess dorsal nectary glands that secrete sugar-rich droplets for tending ants. However, the roles of sugar components in ant foraging and larva-tending activities are unknown. Lycaeides (Plebejus) argyrognomon are larvae that are frequently and facultatively attended by various ant species, including Formica japonica, on the host plant Indigofera pseudotinctoria. The larval secretions of this insect contained small amounts of trisaccharides, melezitose and maltotriose, which were not detected in the host plant's flower nectar, and larval secretions of two sympatric and myrmecophilous lycaenids, Zizeeria maha and Everes argiades. Melezitose and maltotriose, along with sucrose, were preferred by the worker ants. Of the four sugar mixture samples that mimicked I. pseudotinctoria floral nectar and the larval secretions of three lycaenids, respectively, the L. argyrognomon mimic was the most preferred by F. japonica ants. Moreover, the removal of trisaccharides from this mimic significantly reduced its stimulatory activity to ant feedings. These results indicated that the sugar composition of L. argyrognomon larval secretions is suited to the feeding preference of F. japonica ants, and that the trisaccharide components play a key role in increasing their preference. However, only half of the ants responded to the L. argyrognomon mimic even at the concentration corresponding to the maximum total sugar concentration in the collected larval secretions. The fact that the secretions of all L. argyrognomon larvae did not have sufficient sugar levels to stimulate ant feedings suggests that the production of sugar-rich secretions and trisaccharide components is metabolically costly for the larvae and that components other than sugars may be involved in ant attendance.

Polyhydroxy Acids as Fabaceous Plant Components Induce Oviposition of the Common Grass Yellow Butterfly, Eurema Mandarina.

The common grass yellow butterfly, Eurema mandarina is a Fabaceae-feeding species, the females of which readily oviposit on Albizia julibrissin and Lespedeza cuneata in mainland Japan. We previously demonstrated that the methanolic leaf extracts of these plants, and their highly polar aqueous fractions strongly elicit female oviposition. Furthermore, the three subfractions obtained by ion-exchange chromatographic separation of the aqueous fraction have been found to be less effective alone, but synergistically stimulate female oviposition when combined. This indicates that female butterflies respond to multiple compounds with different acidity. We have previously identified d-pinitol from the neutral/amphoteric subfractions and glycine betaine from the basic subfractions as oviposition stimulants of E. mandarina. The present study aimed to identify active compounds in the remaining acidic subfractions of A. julibrissin and L. cuneata leaf extracts. GC-MS analyses of trimethylsilyl-derivatized samples revealed the presence of six compounds in the acidic subfractions. In bioassays using these authentic chemicals, erythronic acid (EA) and threonic acid (TA) were moderately active in eliciting oviposition responses in E. mandarina, with their d-isomers showing slightly higher activity than their l-isomers. Female responsiveness differed between d-EA and l-TA, the major isomers of these compounds in plants, with the response to d-EA reaching a plateau at concentrations above 0.005% and that to l-TA peaking at a concentration of 0.01%. The natural concentrations of d-EA and l-TA in fresh A. julibrissin and L. cuneata leaves were sufficient to stimulate oviposition. Furthermore, mixing 0.001% d-EA or 0.001% l-TA, to which females are mostly unresponsive, with 0.1% d-pinitol resulted in a synergistic enhancement of the oviposition response. These findings demonstrate that E. mandarina females utilize both polyhydroxy acids, EA and TA, as chemical cues for oviposition.

Isolation of Fluorescent Benzoxazines with Neuroprotective Activity from the Olive Weevil Pimelocerus perforatus.

The weevil Pimelocerus perforatus poses a serious pest problem for olive cultivation in Japan. Two new racemic fluorescent benzoxazines, designated as pimeforazine A ((±)-1) and pimeforazine B ((±)-2), were successfully isolated from P. perforatus. Their structures, including the absolute configurations of their resolved enantiomers, were determined using spectroscopic methods, single-crystal X-ray diffraction, and electronic circular dichroism calculations. The neuroprotective activity of the isolated compounds was evaluated against hydrogen peroxide-induced cellular damage in SH-SY5Y human neuroblastoma cells. Compounds (±)-1 and (±)-2 exhibited neuroprotective effects.

Triterpenoid Saponins from the Fruits of Symplocos lucida as ß-Glucuronidase Inhibitors.

A new triterpenoid saponin and five known ones were isolated from the fruits of Symplocos lucida (Thunb.) Siebold & Zucc. Their structures were determined based on the results of spectroscopy analysis, chemical conversions, and X-ray crystallographic analyses. The ß-glucuronidase-inhibitory effects of the isolated and semi-synthesized triterpenoid saponins were also examined.

Sex pheromones from male forewings of the Common Grass Yellow Eurema mandarina.

The common grass yellow Eurema mandarina has a characteristic patch (sex brand) composed of specialized scales (androconia) and wing intermembranous cells on the ventral surface of its male forewing. This structure is specific to males and is thought to release compounds that induce female mate acceptance. However, no study has demonstrated that these compounds function as sex pheromones in the genus Eurema. Here we report the identification of sex pheromones in males of E. mandarina. Chemical analyses revealed that 6,10,14-trimethylpentadecan-2-one (TMP) and (E/Z)-3,7,11,15-tetramethylhexadec-2-enal [(E/Z)-phytal] were male-specific and abundant in particular regions of the male forewings. TMP was highest in the sex brand, whereas (E/Z)-phytal was concentrated in the anal cell (cell 2 A), lacking androconia and intermembranous cells. The content of these compounds increases with age in males after emergence. In bioassays, virgin females displayed a posture of bending their abdomens as mating acceptance in response to stimulation by fresh male forewings. However, solvent-washed male wings did not induce such female responses, suggesting that some compounds from male wings serve as triggers. When we examined female responses to compounds applied to solvent-washed male wings, authentic TMP and (E/Z)-phytal alone showed little activity. However, the mixture elicited abdomen-bending responses in one-third of the females. Therefore, TMP and (E/Z)-phytal were found to act synergistically as aphrodisiac sex pheromones for E. mandarina females, although these activities were weak.

Electrospray ionization mass spectrometry and nuclear magnetic resonance spectroscopy data for anacardic acid derivatives.

The data presented here are related to the research paper entitled "Janohigenins: Long-chain anacardic acid derivatives with neuroprotective activity from Ophiopogon japonicus seeds" (Ohta et al., 2021). In this data article, we provide electrospray ionization mass spectrometry (ESIMS) and 1D and 2D nuclear magnetic resonance (NMR) spectroscopy data of four new anacardic acid derivatives, janohigenins isolated from the seeds of Ophiopogon japonicus.

Chemical Identity of Cuticular Lipid Components in the Mimetic Swallowtail Butterfly Papilio polytes.

The swallowtail Papilio polytes shows Batesian and female-limited polymorphic mimicry. In Japan, P. polytes females have two different forms: the cyrus form is non-mimetic and resembles males, whereas the polytes form mimics Pachliopta aristolochiae and Byasa (Atrophaneura) alcinous as unpalatable models. During mating, P. polytes males use cuticular lipids to distinguish non-mimetic females from conspecific males and sympatric sister species. In this study, we investigated whether compositional differences in cuticular lipids exist between mimetic and non-mimetic females of P. polytes and between mimetic females and their model species. The mimetic and non-mimetic females had nearly identical cuticular lipid profiles, which differed from those of males. The two model species exhibited sexually dimorphic and species-specific cuticular lipid compositions, which were distinctly different from those of mimetic P. polytes females. These results strongly suggest that P. polytes females maintain the identity of cuticular lipid profiles regardless of the mimicry type, and this feature helps males recognize mimetic females as the correct mating partners.

Janohigenins: Long-chain anacardic acid derivatives with neuroprotective activity from Ophiopogon japonicus seeds.

Eight hitherto undescribed long-chain anacardic acid derivatives, janohigenins, were isolated from the endosperm of Ophiopogon japonicus seed, and their structures were elucidated employing spectroscopic and chemical methods. The neuroprotective activity of the isolated compounds was evaluated against rotenone-induced cellular damage in SH-SY5Y human neuroblastoma cells. Janohigenins exhibited noticeable neuroprotection at 1 µM.

Asaroidoxazines from the Roots of Asarum asaroides Induce Apoptosis in Human Neuroblastoma Cells.

Plants in the family Aristolochiaceae contain phenanthrene skeleton-containing chemical constituents that exhibit nephrotoxic, carcinogenic, mutagenic, anti-inflammatory, and cytotoxic effects. Two new phenanthrene-containing 1,2-oxazin-6-ones, designated as asaroidoxazine A (1) and asaroidoxazine B (2), and a known aristolactam, 5-methoxyaristololactam I (3), were isolated from the roots of Asarum asaroides. The structures of compounds 1 and 2 were determined using spectroscopic methods and X-ray crystallography. Treatment of SH-SY5Y human neuroblastoma cells with 1 µM of asaroidoxazine A (1) induced nuclear condensation as well as caspase-3/7 activation, indicating that this compound is a strong apoptosis inducer in neuronal cells. This is the first report of apoptosis induction by phenanthrene-containing oxazines.

Nuclear magnetic resonance spectroscopy and mass spectrometry data for sulfated isoguanine glycosides.

The data presented here are related to the research paper entitled "Rare sulfated purine alkaloid glycosides from Bruchidius dorsalis pupal case" [1]. In this data article, we provide 1D and 2D nuclear magnetic resonance (NMR) spectroscopy and electrospray ionization mass spectrometry (ESIMS) data of three undescribed sulfated purine alkaloids, locustoside A disulfate, saikachinoside B disulfate, and saikachinoside A trisulfate isolated from the pupal case of the wild bruchid seed beetle Bruchidius dorsalis (Chrysomelidae, Bruchinae) infesting the seed of Gleditsia japonica Miquel (Fabaceae).

NMR and ESIMS data for bisabolane-type sesquiterpenoids.

The data presented here are related to the research paper entitled "Norbisabolane and bisabolane sesquiterpenoids from the seeds of Angelica keiskei" [1]. In this data article, we provide 1D and 2D nuclear magnetic resonance (NMR) spectroscopy and electrospray ionization mass spectrometry (ESIMS) data of three undescribed norbisabolane- and bisabolene-type sesquiterpenoids, ashitabaol B-D isolated from the seeds of Angelica keiskei.

Quantitative assay of targeted proteome in tomato trichome glandular cells using a large-scale selected reaction monitoring strategy.

BACKGROUND: Glandular trichomes found in vascular plants are called natural cell factories because they synthesize and store secondary metabolites in glandular cells. To systematically understand the metabolic processes in glandular cells, it is indispensable to analyze cellular proteome dynamics. The conventional proteomics methods based on mass spectrometry have enabled large-scale protein analysis, but require a large number of trichome samples for in-depth analysis and are not suitable for rapid and sensitive quantification of targeted proteins. RESULTS: Here, we present a high-throughput strategy for quantifying targeted proteins in specific trichome glandular cells, using selected reaction monitoring (SRM) assays. The SRM assay platform, targeting proteins in type VI trichome gland cells of tomato as a model system, demonstrated its effectiveness in quantifying multiple proteins from a limited amount of sample. The large-scale SRM assay uses a triple quadrupole mass spectrometer connected online to a nanoflow liquid chromatograph, which accurately measured the expression levels of 221 targeted proteins contained in the glandular cell sample recovered from 100 glandular trichomes within 120 min. Comparative quantitative proteomics using SRM assays of type VI trichome gland cells between different organs (leaves, green fruits, and calyx) revealed specific organ-enriched proteins. CONCLUSIONS: We present a targeted proteomics approach using the established SRM assays which enables quantification of proteins of interest with minimum sampling effort. The remarkable success of the SRM assay and its simple experimental workflow will increase proteomics research in glandular trichomes.

The Role of N,N,N-Trimethylglycine in Oviposition of Eurema mandarina on Albizia julibrissin.

The common grass yellow Eurema mandarina (Lepidoptera: Pieridae) uses the silk tree Albizia julibrissin (Fabaceae) as a primary host in Japan. We previously reported that D-pinitol, a cyclitol found in fresh leaves of A. julibrissin, solely elicits moderate oviposition responses from females. However, the aqueous neutral/amphoteric fraction of the fresh leaf extract containing D-pinitol weakly induces oviposition. Moreover, the aqueous neutral/amphoteric/basic fraction was significantly more active than the neutral/amphoteric fraction in eliciting responses, indicating that some basic compounds are involved in stimulating oviposition. High-resolution mass spectrometry and proton nuclear magnetic resonance measurements revealed that the aqueous basic faction contains N,N,N-trimethylglycine (trivial name: glycine betaine) in alkali metal salt form. The average concentration of this quaternary ammonium compound in fresh leaves was estimated to be 0.012% w/w in high performance liquid chromatography analyses. The authentic N,N,N-trimethylglycine induced oviposition at concentrations greater than 0.001% (w/v) and slightly enhanced female responses to the aqueous neutral fraction and authentic D-pinitol. However, its analogues, N,N-dimethylglycine, N-methylglycine, and glycine as well as its precursor choline were inactive. These results demonstrate that N,N,N-trimethylglycine, together with D-pinitol, serves as an stimulant of E. mandarina for oviposition on the leaves of A. julibrissin.

Response of neutrophilic Shewanella violacea to acid stress: growth rate, organic acid production, and gene expression.

Neutrophilic Shewanella violacea is isolated from deep-sea sediments and its response to high pressure and high salinity has been investigated. Here, the pure effects of acidic pH on S. violacea physiology were examined, aiming at further understanding of its stress response mechanism. S. violacea could grow at initial pH of 5.0-7.0 without pH adjustment during the test at atmospheric pressure, and the lowest growth rate was obtained at pH 5.0. The pH of the same growth culture with an initial pH of 5.0 rose toward a neutral pH of ~ 7.0 at the exponential growth phase, indicating that S. violacea has a mechanism for acid neutralization. When S. violacea cells were grown at the fixed pH of 5.0, about five times higher concentrations of butyric and isovaleric acids were produced than at pH 7.0. The expression level of the genes encoding three enzymes for isovaleric acid synthesis from L-leucine was also found to be upregulated in S. violacea cells grown at the fixed pH of 5.0 compared with at pH 7.0 through RNA-seq analysis. Therefore, S. violacea at least produces isovaleric acid in its response to acid stress, which further deepens our understanding of the stress response mechanism inherent in this bacterium.

HPLC profiles and spectroscopic data of cassane-type furanoditerpenoids.

The data presented here are related to the research paper entitled "Hydroxylated furanoditerpenoids from the pupal case produced by the bruchid beetle Sulcobruchus sauteri inside the seed of Caesalpinia decapetala" (Akihara et al., 2018) [1]. In this data article, we provide high-performance liquid chromatography (HPLC) profiles of seven undescribed hydroxylated furanoditerpenoids, caesalsauteolide, 2-hydroxycaesaljapin, 2,7-dihydroxycaesaljapin, 2-hydroxycaesalacetal, caesalsauterol, 6-acetylcaesalsauterol, norcaesalsauterol isolated from the pupal cases produced by Sulcobruchus sauteri and four known compounds, caesaljaponin A (Kamikawa et al., 2015) [2], caesaljaponin B (Kamikawa et al., 2015) [2], caesalacetal (Kamikawa et al., 2016) [3], and caesaljapin (Kamikawa et al., 2016; Ogawa et al., 1992) [3], [4] isolated from the cotyledons of the intact seeds of Caesalpinia decapetala. Besides, 1D NMR, 2D NMR, and HRESIFTMS data of the seven undescribed furanoditerpenoids are also presented.

Hydroxylated furanoditerpenoids from pupal cases produced by the bruchid beetle Sulcobruchus sauteri inside the seeds of Caesalpinia decapetala.

Seven undescribed hydroxylated cassane-type furanoditerpenoids were isolated from pupal cases formed from the secretion/excretion of the larvae of the wild bruchid seed beetle Sulcobruchus sauteri in infested Caesalpinia decapetala seeds, and their structures were elucidated by interpreting their spectra. The hydroxylated furanoditerpenoids found in the pupal cases were not present in the seeds of the host plant. Caesalacetal and caesaljapin obtained from the intact seeds exhibited larvicidal activity against the larvae of Aedes albopictus, while the hydroxylated furanoditerpenoids isolated from the pupal cases were inactive. The larvae of S. sauteri are proposed to detoxify larvicidal diterpenoids that occur in the seeds of the host plant by regiospecific hydroxylation.

Sulfated Purine Alkaloid Glycosides from the Pupal Case Built by the Bruchid Beetle Bruchidius dorsalis Inside the Seed of Gleditsia japonica.

Three new sulfated isoguanine alkaloid glycosides, designated as saikachinoside A monosulfate (1), saikachinoside A disulfate (2), and locustoside B disulfate (3), have been isolated from the pupal case of the wild bruchid seed beetle Bruchidius dorsalis (Chrysomelidae, Bruchinae) infesting the seed of Gleditsia japonica Miq. (Fabaceae). Their structures were determined by spectroscopic methods and the inhibitory activity of 2 and 3 against acid phosphatase was evaluated.

Effects of mating on host selection by female small white butterflies Pieris rapae (Lepidoptera: Pieridae).

Mating might significantly affect the host selection behaviors of phytophagous insects. Here, we investigated the post-mating changes in behavioral and antennal responses of Pieris rapae (Lepidoptera: Pieridae) females to host plant volatiles. In two-choice bioassays using artificial plant models, mated females visited the model scented with synthetic blends (15-, 9-, or 6-components) of cabbage plant volatiles more frequently than the unscented control, whereas virgin females did not exhibit this preference. Because single compounds and the 3-component blend did not induce preferential visiting, mated females apparently utilized complex odor blends as their host-finding cue. Moreover, 2- to 4-day-old mated females visited the models, scented and unscented, more frequently than did their virgin counterparts. Therefore, mating enhanced the host-finding behavior of young females and their responsiveness to plant volatiles. Gas chromatography-electroantennographic detector analysis revealed that eight of the 15 compounds in the cabbage plant volatiles elicited responses from female antennae. However, post-mating and age-dependent changes in antennal responses were not detected. Because female peripheral (antennal) sensitivity to volatiles remained practically unchanged after emergence, post-mating changes in host selection might be attributed to changes in the central nervous system.