Changes in Physicochemical Properties and Flavor Characteristics of Rosa roxburghii Tratt. Fruit Vinegar during Fermentation

This paper investigated the compositional changes of Rosa roxburghii Tratt. fruit vinegar during fermentation. By using Rosa roxburghii Tratt. as raw material and using the whole liquid fermentation technique, fruit vinegar was prepared by fermenting alcoholic and acetic acids simultaneously. The physicochemical properties of the fermentation process were dynamically monitored. Headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) and the odor activity value (OAV) were utilized to analyze volatile flavor components. As fermentation proceeded, soluble solids, pH, total sugars, and reduced sugars decreased, while total acid and VC contents increased. From the original juice to the end of acetic acid fermentation, the total acid and VC contents ranged from 1.86 g/100 mL and 956.82 mg/100 mL to 6.79 g/100 mL and 1275.88 mg/100 mL. Oxalic acid, quinic acid, pyruvic acid, ascorbic acid, lactic acid, acetic acid, and fumaric acid showed varying degrees of increasing (P<0.05). By contrast, formic acid, citric acid, maleic acid, and succinic acid exhibited little variation. A total of 92 volatile compounds were detected in the Rosa roxburghii Tratt. fruit vinegar, and with the addition of OAV analysis, ten volatile compounds were identified as key aroma compounds, which included nonanal, acetaldehyde, ethyl isobutyrate, ethyl butyrate, ethyl 2-methylbutyrate, ethanol, isoamyl alcohol, leaf alcohol, linalool, and phenyl ethanol. Among these components, ethyl butyrate and leaf alcohol contributed most to the aroma of Rosa roxburghii Tratt. fruit vinegar. Green grass and green apples were characteristic aromas of this vinegar. The results of the study would provide a theoretical basis and practical guidance for the effective control of fermentation conditions, revealing the physicochemical characteristics and flavor features of fermented Rosa roxburghii Tratt. fruit vinegar, forming a method for quality evaluation of Rosa roxburghii Tratt. fruit vinegar, and formulating quality standards

Critical role of peroxisome proliferator-activated receptor α in promoting platelet hyperreactivity and thrombosis under hyperlipidemia

Platelet hyperreactivity and increased atherothrombotic risk are specifically associated with dyslipidemia. Peroxisome proliferator-activated receptor alpha (PPARα) is an important regulator of lipid metabolism. It has been suggested to affect both thrombosis and hemostasis, yet the underlying mechanisms are not well understood. In this study, the role and mechanism of PPARα in platelet activation and thrombosis related to dyslipidemia were examined. Employing mice with deletion of PPARα (Pparα-/-), we demonstrated that PPARa is required for platelet activation and thrombus formation. The effect of PPARα is critically dependent on platelet dense granule secretion, and is contributed by p38MAPK/Akt, fatty acid b-oxidation, and NAD(P)H oxidase pathways. Importantly, PPARα and the associated pathways mediated a prothrombotic state induced by a high-fat diet and platelet hyperactivity provoked by oxidized low density lipoproteins. Platelet reactivity was positively correlated with the levels of expression of PPARα, as revealed by data from wild-type, chimeric (Pparα+/-), and Pparα-/- mice. This positive correlation was recapitulated in platelets from hyperlipidemic patients. In a lipid-treated megakaryocytic cell line, the lipid-induced reactive oxygen species-NF-kB pathway was revealed to upregulate platelet PPARα in hyperlipidemia. These data suggest that platelet PPARα critically mediates platelet activation and contributes to the prothrombotic status under hyperlipidemia

The ER-membrane transport system is critical for intercellular trafficking of the NSm movement protein and Tomato Spotted Wilt Tospovirus

Plant viruses move through plasmodesmata to infect new cells. The plant endoplasmic reticulum (ER) is interconnected among cells via the ER desmotubule in the plasmodesma across the cell wall, forming a continuous ER network throughout the entire plant. This ER continuity is unique to plants and has been postulated to serve as a platform for the intercellular trafficking of macromolecules. In the present study, the contribution of the plant ER membrane transport system to the intercellular trafficking of the NSm movement protein and Tomato spotted wilt tospovirus (TSWV) is investigated. We showed that TSWV NSm is physically associated with the ER membrane in Nicotiana benthamiana plants. An NSm-GFP fusion protein transiently expressed in single leaf cells was trafficked into neighboring cells. Mutations in NSm that impaired its association with the ER or caused its mis-localization to other subcellular sites inhibited cell-to-cell trafficking. Pharmacological disruption of the ER network severely inhibited NSm-GFP trafficking but not GFP diffusion. In the Arabidopsis thaliana mutant rhd3 with an impaired ER network, NSm-GFP trafficking was significantly reduced, whereas GFP diffusion was not affected. We also showed that the ER-to-Golgi secretion pathway and the cytoskeleton transport systems were not involved in the intercellular trafficking of TSWV NSm. Importantly, TSWV cell-to-cell spread was delayed in the ER-defective rhd3 mutant, and this reduced viral infection was not due to reduced replication. On the basis of robust biochemical, cellular and genetic analysis, we established that the ER membrane transport system serves as an important direct route for intercellular trafficking of NSm and TSWV

Fast multipole boundary element analysis for 2D problems of magneto-electro-elastic media

A two-dimensional (2D) fast multipole boundary element analysis of magneto-electro-elastic media has been developed in this paper. Fourier analysis is employed to derive the fundamental solution for the plane-strain magneto-electro-elasticity. The final formulations are very similar to those for the 2D potential problems, and hence it is quite easy to implement the fast multipole boundary element method. The results are verified by comparison with the analytical solutions to illustrate the accuracy and efficiency of the approach. The numerical examples of multi-inclusion magneto-electro-elastic composites are considered to show the versatility of the proposed approach in smart structure applications