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- Author or Editor: J. Du x
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Summary
The method of high-performance liquid chromatography (HPLC) with diode array detector (DAD) was used and validated for the simultaneous determination of nine flavonoids (rutin, myricetin, quercitrin, quercetin, luteolin, genistein, kaempferol, apigenin, and isorhamnetin) in beagle dog plasma. Plasma sample was pre-treated with acetonitrile (containing 0.05% formic acid). Chromatographic separation was performed on a kromasil C18 column (250 × 4.6 mm, 5 µm) maintained at 35 °C. The mobile phase was a mixture of methanol and 0.2% formic acid with a step linear gradient. At 1.0 mL min−1 flow rate, the eluent of other eight flavonoids was detected simultaneously at 360 nm with good separation except genistein (detected at 254 nm). Under optimum conditions, the correlation coefficient between the peak area and the concentrations for each analyte was all above 0.999. The intra-day and inter-day precisions were less than 10% for all analytes. The limit of detection and the limit of quantification for the selected nine flavonoids were 0.006–0.03 and 0.02–0.12 g mL−1, respectively. The extracted recoveries of selected nine flavonoids were 74.02%–99.37%. The assay has been successfully applied to determine concentrations of nine flavonoids in plasma from beagle dog after being intravenously administrated Ginkgo biloba extract.
Abstract
Background and aims
Numerous studies on behavioral addictions (BAs) have reported gray matter (GM) alterations in multiple brain regions by using voxel-based morphometry (VBM). However, findings are poorly replicated and it remains elusive whether distinct addictive behaviors are underpinned by shared abnormalities. In this meta-analysis, we integrated VBM studies on different BAs to investigate common GM abnormalities in individuals with BAs.
Methods
We performed a systematic search up to January 2019 in several databases for VBM studies investigating GM differences between individuals with BAs and healthy controls. The reference lists of included studies and high-quality reviews were investigated manually. Anisotropic effect-size signed differential mapping was applied in this meta-analysis.
Results
Twenty studies including 505 individuals with BAs and 564 healthy controls met the inclusion criteria. Compared with healthy controls, individuals with BAs showed GM atrophy in the left anterior cingulate (extending to the left medial superior frontal gyrus and bilateral orbitofrontal gyrus), right putamen and right supplementary motor area. Subgroup analysis found heterogeneity in gender and subtypes of BAs. Meta-regression revealed that GM decreases in the left anterior cingulate and right supplementary motor area were positively correlated with addictive severity. Higher impulsivity was associated with smaller volume of the left anterior cingulate.
Discussion and conclusions
Our findings on BAs were mainly derived from internet gaming disorder (IGD) and pathological gambling (PG) studies, preliminarily suggesting that GM atrophy in the prefrontal and striatal areas might be a common structural biomarker of BAs.
After suffering from mechanical injury and fungal infection, grapes are perishable. Botrytis cinerea, the causal agent of gray mould, is a critical pathogen for grapes. In this study, the inhibitory effect of Pseudomonas fluorescens on the formation of gray mould on grapes during the postharvest storage was investigated on “Kyoho” grape. The results suggest that a living cell suspension of P. fluorescens significantly inhibited spore germination of B. cinerea, and significantly reduced the incidence of grape gray mould. Moreover, compared with the control, the fruit inoculated with P. fluorescens had elevated activities of polyphenol oxidase (PPO), peroxidase (POD), catalase (CAT), phenylalanine ammonia-lyase (PAL), chitinase (CHI), and β-1,3-glucanase (GLU). Increase in enzyme activity correlated with enhanced host resistance. In addition, there was little difference in storage quality between the treated group and control group, indicating no adverse effects of the induced defence response on fruit quality.
The increasing consumer demand for less processed and more natural food products – while improving those products’ quality, safety, and shelf-life – has raised the necessity of chemical preservative replacement. Biopreservation refers to extended storage life and enhanced safety of foods using the natural microflora and (or) their antibacterial products. Chitinolytic enzymes are of biotechnological interest, since their substrate, chitin, is a major structural component of the cell wall of fungi, which are the main cause of the spoilage of food and raw plant material. Among the several organisms, many bacteria produce chitinolytic enzymes, however, this behaviour is not general. The chitinase activity of the lactic acid bacteria is scarcely known and studied.
The aim of the present study was to select Lactobacillus strains that have genes encoding chitinase, furthermore, to detect expressed enzymes and to characterise their chitinase activity. Taking into consideration the importance of chitin-bindig proteins (CBPs) in the chitinase activity, CBPs were also examined. Five Lactobacillus strains out of 43 strains from 12 different species were selected by their chitinase coding gene. The presence of the chitinase and chitin-biding protein production were confirmed, however, no chitinolytic activity has been identified.
