Oxidation of low-density lipoprotein (LDL) has been implicated in atherogenesis. Antioxidants that prevent LDL from oxidizing may reduce atherosclerosis. This study investigated LDL antioxidant activity in edible plant products for development of dietary supplementation to prevent atherosclerosis. Fifty-two kinds of edible plants were extracted using 70% aqueous ethanol solution, and the antioxidant activity of the extracts, which inhibit human LDL oxidation induced by copper ion, was determined on the basis of the oxidation lag time and represented as epigallocatechin 3-gallate equivalent. 1,1-Diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity and total phenolic content were also measured for comparisons with antioxidant activity in LDL. Plant products showing the greatest activity in LDL oxidation assay were akamegashiwa (Mallotus japonicus) leaf, Japanese privet (Ligustrum japonicum) leaf, green tea [Camellia sinensis (L.) O. Kuntze], and astringent persimmon (Diospyros kaki). The present study revealed high levels of LDL antioxidant activity in plant products for which such activity levels are underestimated in the DPPH radical scavenging assay and Folin-Ciocalteu assay.
An investigation to systematize empirical equations for the shear wave velocity of soils was made in terms of four characteristic indexes. The adopted indexes are the N‐value of the Standard Penetration Test, depth where the soil is situated, geological epoch and soil type. As some of these indexes are variates belonging to interval scales while others belong to nominal or ordinal scales, the technique known as a multivariate analysis cannot be employed. A new approach to the theory of quantification, after C. Hayashi, was introduced and developed for solving this difficulty. Fifteen sets of empirical equations to estimate low strain shear wave velocity theoretically may be obtained by combining the above four indexes. All of these sets were derived by use of about 300 data, and their accuracies were evaluated by means of correlation coefficients between the measured and estimated shear wave velocities. The best equation was found to be the one which included all the indexes, and its correlation coefficient was 0.86. The empirical equation relating the standard penetration N‐value to the shear wave velocity provided a correlation of only 0.72, and is one of the lowest ranking among the 15 sets of equations.
An agar-degrading Thalassomonas bacterium, strain JAMB-A33, was isolated from the sediment off Noma Point, Japan, at a depth of 230 m. A novel alpha-agarase from the isolate was purified to homogeneity from cultures containing agar as a carbon source. The molecular mass of the purified enzyme, designated as agaraseA33, was 85 kDa on both SDS-PAGE and gel-filtration chromatography, suggesting that it is a monomer. The optimal pH and temperature for activity were about 8.5 and 45 degrees C, respectively. The enzyme had a specific activity of 40.7 U/mg protein. The pattern of agarose hydrolysis showed that the enzyme is an endo-type alpha-agarase, and the final main product was agarotetraose. The enzyme degraded not only agarose but also agarohexaose, neoagarohexaose, and porphyran.
Lignin, an aromatic polymer of phenylpropane units joined predominantly by β-O-4 linkages, is the second most abundant biomass component on Earth. Despite the continuous discharge of terrestrially produced lignin into marine environments, few studies have examined lignin degradation by marine microorganisms. Here, we screened marine isolates for β-O-4 cleavage activity and determined the genes responsible for this enzymatic activity in one positive isolate. Novosphingobium sp. strain MBES04 converted all four stereoisomers of guaiacylglycerol-β-guaiacyl ether (GGGE), a structural mimic of lignin, to guaiacylhydroxypropanone as an end metabolite in three steps involving six enzymes, including a newly identified Nu-class glutathione-S-transferase (GST). In silico searches of the strain MBES04 genome revealed that four GGGE-metabolizing GST genes were arranged in a cluster. Transcriptome analysis demonstrated that the lignin model compounds GGGE and (2-methoxyphenoxy)hydroxypropiovanillone (MPHPV) enhanced the expression of genes in involved in energy metabolism, including aromatic-monomer assimilation, and evoked defense responses typically expressed upon exposure to toxic compounds. The findings from this study provide insight into previously unidentified bacterial enzymatic systems and the physiological acclimation of microbes associated with the biological transformation of lignin-containing materials in marine environments.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.