Luteolin, an abundant flavonoid in the leaves of Capsicum annuum, has antioxidant activity and is, thus, a key chemical for promoting plant residue utilization, especially for the development of healthcare products. We assessed the inhibitory effect of luteolin and its glycosides on osteoclastic differentiation in human cells and found that the differentiation was effectively inhibited at noncytotoxic concentrations. We also screened 47 varieties of C.
View Article and Find Full Text PDFWe previously reported that fluid soybean lecithin (SL) undergoes heat deterioration by the newly reported pseudo-Maillard rearrangement reaction. To inhibit heat deterioration, SLs were treated with metal silicates, such as magnesium silicate and calcium silicate. When soybean fatty acid was added to SL before treatment with calcium silicate, the color index after heating improved significantly as the acid value increased from 10 to 35 mg KOH/g.
View Article and Find Full Text PDFHere, we report the identification of the gene encoding a novel enzyme, 3-(5-oxo-2-thioxoimidazolidin-4-yl) propionic acid desulfhydrase, in Burkholderia sp. HME13. The enzyme converts 3-(5-oxo-2-thioxoimidazolidin-4-yl) propionic acid and H2O to 3-(2,5-dioxoimidazolidin-4-yl) propionic acid and H2S.
View Article and Find Full Text PDFA novel enzyme, thiourocanate hydratase, which catalyses the conversion of thiourocanic acid to 3-(5-oxo-2-thioxoimidazolidin-4-yl) propionic acid, was isolated from the ergothioneine-utilizing strain, Burkholderia sp. HME13. When the HME13 cells were cultured in medium containing ergothioneine as the sole nitrogen source, thiourocanate-metabolizing activity was detected in the crude extract from the cells.
View Article and Find Full Text PDFPest Manag Sci
January 2020
Background: Pest management using botanicals has been widely practiced in sub-Saharan Africa and other parts of the world in recent times. The natural compounds present in these botanicals are known to be responsible for the protection they offer against insect pests. Some of these compounds may act as single compounds to produce an effect or they may be synergistically effective.
View Article and Find Full Text PDFA crude rice extract caused a higher probing response than did the control in the green rice leafhopper, . Bioassay-guided separation led to the isolation of four active compounds, isoscoparin 2″--glucoside, isoscoparin 2″--(6‴-()-feruloyl)glucoside, isoscoparin 2″--(6‴-()--coumaroyl)glucoside, and isovitexin 2″--(6‴-()-feruloyl)glucoside from ODS 40% methanol in water faction. Each of the compounds, or any combination without one of the four compounds, caused weaker probing responses than the crude rice extract.
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 PDF3-(2,4-Dihydroxyphenyl)propionic acid (DDPA) and l-ascorbic acid (vitamin C) show tyrosinase inhibition activity. A synergistic effect on tyrosinase inhibition was observed when the two compounds were mixed. The effect significantly decreased the IC50 value of both compounds.
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 PDFCertain Japonica rice plant varieties (Oryza sativa L.) show resistance to the eggs of the white backed planthopper (Sogatella furcifera Horváth) by the formation of watery lesions and production of benzyl benzoate, an active ovicidal compound. Benzyl benzoate results in high ovicidal activity of S.
View Article and Find Full Text PDFTabtoxinine-β-lactam (TβL), a non-specific bacterial toxin, is produced by Pseudomonas syringae pv. tabaci, the causal agent of tobacco wildfire disease. TβL causes death of plant cells through the inhibition of glutamine synthetase, which leads to an abnormal accumulation of ammonium ions and the characteristic necrotic wildfire lesions.
View Article and Find Full Text PDFWe elucidate the mechanism for inducing the production of ovicidal benzyl benzoate by Japonica rice varieties to kill eggs of the whitebacked planthopper, Sogatella furcifera (Horváth), lying in the rice plant. Even when subjected to physical damage by a needle or damage with water, the rice plant produced no benzyl benzoate. However, significant benzyl benzoate was produced when the plant was damaged with a methanol extract or homogenate of S.
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 PDFThis study assessed pesticide residues in soils, sediments, and vegetables in the Xuan Khe and Hop Ly communes located along the Chau Giang River in the Red River Delta, northern Vietnam. Samples were collected from agricultural areas within and outside of embankments built to prevent flooding. In Xuan Khe, the soils outside of the embankment were more clayey with higher organic matter contents compared with the inside, due to selective deposition during river flooding.
View Article and Find Full Text PDFJ Asian Nat Prod Res
June 2009
Three new flavone C-glycosides with the substitution of the unusual acyl, 2''-O-veratroylisoswertisin (1), 3''-O-2-methylbutyrylisoswertiajaponin (2), and 3''-O-2-methylbutyrylvitexin (3), together with the known compounds of 2''-O-2-methylbutyrylisoswertisin (4), 3''-O-2-methylbutyrylisoswertisin (5), and trollisin I (6) were isolated from the antibacterial fraction of the aqueous extract of the flowers of Trollius chinensis. The structural elucidations of these compounds were carried out by a detailed analysis of the NMR and MS spectra.
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 PDFBiosci Biotechnol Biochem
February 2008
A methanol extract of Cryptomeria japonica completely inhibited feeding by Locusta migratoria. Based on bioassay-guided fractionation, two active terpenols, (+)-ferruginol and (-)-cubebol, were isolated and identified as antifeedants against this insect species. Each compound separately showed weak activity, but they showed intense activity against this insect species 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 PDFBiosci Biotechnol Biochem
April 2007