The development of repellents as alternatives to insecticides has expanded in recent years. However, their use in isopod pest control is limited. To develop an isopod repellent, a plant extract library from wild plants native to the Kochi Prefecture was screened for repellent activity against pillbugs, and 82 samples (87%) exhibited repellent activity.
View Article and Find Full Text PDFPlant defense responses are activated by various exogenous stimuli. We found that an aqueous extract of spent mushroom substrate used for the cultivation of Hypsizygus marmoreus induced defense responses in rice. Fractionation of the spent mushroom substrate extract indicated that the compounds responsible for this induction were neutral and hydrophilic molecules with molecular weights lower than 3 kDa.
View Article and Find Full Text PDFChanges in specialized metabolites were analyzed in barley (Hordeum vulgare) leaves treated with CuCl solution as an elicitor. LC-MS analysis of the CuCl-treated leaves showed the induced accumulation of three compounds. Among them, two were purified by silica gel and ODS column chromatography and preparative HPLC and were identified as 2',3,4,4',6'-pentamethoxychalcone and 2'-hydroxy-3,4,4',6'-tetramethoxychalcone by spectroscopic analyses.
View Article and Find Full Text PDFWe investigated the effect of treatment with hot water extracts from the spent mushroom substrates (SMSs) of and on the resistance of rice leaves to infection. The spraying of the SMS extracts clearly suppressed the development of lesions caused by infection. The accumulation of phytoalexins momilactones A and B, oryzalexin A, and sakuranetin was markedly induced by the spraying of extracts.
View Article and Find Full Text PDFThe inducible metabolites in rice leaves treated with 1 mM jasmonic acid (JA) were analyzed using HPLC. We detected an increase in the levels of two compounds, and . Based on the comparison with mass spectra and chromatographic behavior with authentic compounds, and were identified as 13-oxooctadeca-9,11-dienoic acid (13-KODE) and 9-oxooctadeca-10,12-dienoic acid (9-KODE), respectively, which have not been detected in rice to date.
View Article and Find Full Text PDFThe inducible metabolites were analyzed in barley leaves inoculated with Bipolaris sorokiniana, the causal agent of spot blotch of barley. HPLC analysis revealed that B. sorokiniana-infected leaves accumulated 4 hydrophilic compounds.
View Article and Find Full Text PDFThe Poaceae is a large taxonomic group consisting of approximately 12,000 species and is classified into 12 subfamilies. Gramine and benzoxazinones (Bxs), which are biosynthesized from the tryptophan pathway, are well-known defensive secondary metabolites in the Poaceae. We analyzed the presence or absence of garamine and Bxs in 64 species in the Poaceae by LC-MS/MS.
View Article and Find Full Text PDFTo elucidate the probing stimulants in rice plants for the white-backed planthopper, Sogatella furcifera, bioassay-guided separations were conducted, which led to the isolation of four active compounds. Using NMR and LC-MS spectra, their structures were determined as isoorientin 2″-O-(6‴-(E)-feruloyl)glucoside, isoorientin 2″-O-(6‴-(E)-p-coumaroyl)glucoside, tricin 5-O-glucoside, and isoscoparin 2″-O-(6‴-(E)-feruloyl)glucoside.
View Article and Find Full Text PDFZ Naturforsch C J Biosci
November 2015
The feeding response of larvae of the swallowtail butterfly, Graphium sarpedon nipponum (Lepidoptera: Papilionidae), is elicited by a methanolic extract from camphor tree (Cinnamomum camphora) leaves. Based on bioassay-guided fractionation, three compounds, isolated from the methanolic extract of fresh leaves of the camphor tree, were revealed to be involved in a multi-component system of feeding stimulants. Structures of these feeding stimulants were identified as sucrose, 5-O-caffeoylquinic acid and quercetin 3-O-β-glucopyranoside by NMR and LC-MS.
View Article and Find Full Text PDFThe objective of this study was to establish a high quality progeny production system for the house fly parasitoid, Spalangia endius (Hymenoptera: Pteromalidae), by stockpiling hosts. We performed two host killing methods before host storage: (i) heat-killed by 30 min exposure to 50°C or (ii) freeze-killed by 10 min exposure to -80°C. The average number of parasitoids that emerged from nonstored house fly pupae after heat- or freeze-killing was not significantly different from live pupae.
View Article and Find Full Text PDFThe acceptance of camphor tree (Cinnamomum camphora) as a host plant for the larvae of common bluebottle (Graphium sarpedon nipponum) was explained by the presence of feeding stimulants in the leaves. When the active methanol extract of C. camphora leaves was separated into hexane and water layers, both layers showed high feeding activities for the larvae of G.
View Article and Find Full Text PDFBiosci Biotechnol Biochem
February 2011
Floral scent has been shown to elicit behavioral responses by butterflies which forage for flowers after receiving appropriate signals. In comparison with investigations about the role of floral scent, those of foliar odor are, however, very few. In this study, the foliar volatiles of Cinnamomum camphora (Lauraceae), which had been collected by air entrainment, exhibited activities toward Graphium sarpedon nipponum (Papilionidae) in both electrophysiological and behavioral tests.
View Article and Find Full Text PDFEight compounds isolated from Indian barnyard millet have been identified as L-malic acid, trans-aconitic acid, (+)-isocitric acid, 5-O-caffeoylquinic acid, 4-O-caffeoylquinic acid, isocarlinoside, 2"-O-rhamnosylisoorientin, and 7-O-(2"-O-glucuronosyl)glucuronosyltricin, respectively. These compounds showed high antifeeding activity against brown planthopper only when they were combined.
View Article and Find Full Text PDF2,3-Dihydro-1H-imidazo[1,2-a]pyridine-4-ylium derivatives with UV absorption at 350 nm were formed by reaction of one molar of any sugar except 2-deoxysugars with two molar of phosphatidylethanolamines involving a new pseudo Maillard rearrangement reaction. To elucidate the reaction mechanism, 2-aminoethyl dihydrogenphosphate, which had a partially similar structural moiety to PE, was reacted with D-galactose. Though the UV absorption at 365 nm was not observed and the four pyridinium derivatives were also not formed in the reactant solution, the UV absorption at 286 nm and browning of the reactant solution were observed.
View Article and Find Full Text PDFA new cucurbitane glucoside, 23-O-beta-D-glucopyranosyl-7-hydroxy-3-O-malonylcucurbita-5,24-dien-19-al, named momordicine V, has been isolated from Momordica charantia leaves, along with the previously reported compounds, momordicines I, II, IV and 3-O-malonylmomordicine I. The structure of the new compound was established on the basis of spectral analysis, as well as by its conversion to momordicine II by alkaline catalyzed hydrolysis. Momordicine V deterred significantly the oviposition by L.
View Article and Find Full Text PDFNovel four 2,3-dihydro-1H-imidazo[1,2-a]pyridine-4-ylium derivatives were obtained with increase of UV absorption at 350 nm and browning of the solution by heating paste lecithin from soybean (SL) in octane. These four derivatives were formed by reaction of one molar of any sugar except 2-deoxysugars with two molar of phosphatidylethanolamines (PE) in SL. To confirm the reaction mechanism, several (13)C-labeled-sugars were reacted with 1,2-di-O-stearoyl-sn-glycero-3-phosphatidylethanolamine (DSPE), respectively.
View Article and Find Full Text PDFSweet pepper (Capsicum annuum) leaves at the mature stage have strong ovipositional deterrence against Liriomyza trifolii (Burgess) (Diptera, Agromyzidae), whereas the cotyledons are fiercely attacked by the fly. Treatment of the cotyledons with 50 microM and 100 microM of a jasmonic acid (JA) solution caused the plant to acquire strong oviposition deterrence against the leafminer. An HPLC analysis of the JA-treated cotyledons revealed the inducible accumulation of a compound.
View Article and Find Full Text PDFTwo new flavonoid glycosides kaempferol 3-O-beta-D-apiofuranosyl-(1-->6)-beta-D-glucopyranoside (1), and quercetin 3-O-beta-D-apiofuranosyl-(1-->6)-beta-D-glucopyranoside (2), together with six known flavonoid glycosides were isolated from the leaves of Solidago altissima L. grown in Kochi of Japan. The structure elucidation of the isolated compounds was performed by acid hydrolysis and spectroscopic methods including UV, IR, ESI-MS, 1D- and 2D-NMR experiments.
View Article and Find Full Text PDFLu xian cao (Hebra pyrolae) is a traditional Chinese medicine used for the treatment of several major diseases. Chimaphilin has been demonstrated one of the major active components in Lu xian cao by modern pharmacological studies. In this study, a liquid chromatography-mass spectrometry method for the determination of chimaphilin in rat plasma was developed and validated.
View Article and Find Full Text PDFThe American serpentine leaf mining fly, Liriomyza trifolii, whose larva feeds on more than 120 plant species is well characterized by its high degree of polyphagy. Observations on the oviposition behavior by L. trifolii demonstrated that among cucurbitaceous plants, Momordica charantia is rarely attacked by L.
View Article and Find Full Text PDFLiriomyza trifolii (Burgess), the American serpentine leafminer fly, is a well-known serious pest in the world. This insect species attacks plants of more than 21 families including Solanaceae plants. A sweet pepper, Capsicum annuum (Solanaceae), on mature stage, however, shows resistance to this leafminer fly.
View Article and Find Full Text PDFFemales of Liriomyza trifolii, a polyphagous leafminer, are often deterred from ovipositing on Momordica charantia leaves. The methanol extract of M. charantia leaves showed strong oviposition deterrent activity against L.
View Article and Find Full Text PDFZ Naturforsch C J Biosci
June 2005
(1S,6R)-2,7(14),10-Bisabolatrien-1-ol-4-one was identified as a germination inhibitor from the methanol extract of Japanese cedar wood, Cryptomeria japonica. The occurrence of this compound in 1 g fresh wood was 2.0 mg, and showed a maximum of 60% germination inhibition at the dose of 20 mg/filter paper (157 microg/cm(2)) against both of lettuce and rice seeds for 4 d.
View Article and Find Full Text PDFFour fatty acid methyl esters identified in the solvent extract of Tribolium confusum (Jacquelin du Val) larvae as kairomones were individually and collectively tested for probing behavior of Peregrinator biannulipes Montrouzier et Signoret. All identified fatty acid methyl eaters, methyl palmitate, methyl linolate, methyl oleate and methyl stearate, exhibited characterisitic kairomonal probing behavior of P. biannulipe toward the lure.
View Article and Find Full Text PDFBiosci Biotechnol Biochem
November 2002
Sandaracopimarinol and (1S,6R)-2,7(14),10-bisabolatrien-1-ol-4-one were isolated and identified from Cryptomeria japonica as repellents against Armadillidium vulgare which is well known as an unpleasant pest in the house and as vegetable pest in Japan. These compounds strongly repelled A. vulgare when they were combined, although each compound alone did not show any activity.
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