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Volatile fatty acid derivatives (VFADs) play a significant role in contributing to flowery–fruity flavor black tea. Innovative black tea is typically crafted from aroma-intensive tea cultivars, such as Jinmudan, using defined production methodologies. In this study, the during-processing tea leaves of innovative black tea were applied as materials, and we selected a total of 45 VFADs, comprising 11 derived aldehydes, nine derived alcohols, and 25 derived esters. Furthermore, the dynamic variations of these VFADs were uncovered. Transcriptome analysis was performed to identify genes involved in the LOX (lipoxygenase) pathway, resulting in the identification of 17 CsLOX genes, one hydrogen peroxide lyase (CsHPL) gene, 11 alcohol dehydrogenases (CsADH) genes, 11 genes as acyl CoA oxidase (CsACOX) genes, and three allene oxide synthase (CsAOS) genes. Additionally, the expression levels of these genes were measured, indicating that the processing treatments of innovative black tea, particularly turn-over and fermentation, had a stimulation effect on most genes. Finally, qRT-PCR verification and correlation analysis were conducted to explain the relationship between VFADs and candidate genes. This study aims to provide a reference for illuminating the formation mechanisms of aroma compounds in innovative black tea, thereby inspiring the optimization of innovative processing techniques and enhancing the overall quality of black tea. [ABSTRACT FROM AUTHOR]

Isoliensinine (ISO), a natural compound, is a bibenzyl isoquinoline alkaloid monomer in lotus seed, which has strong antioxidant and free radical scavenging activities. The oxidative toxicity caused by glutamic acid overdose is one of the important mechanisms of nerve cell injury, and the oxidative toxicity caused by glutamic acid is related to ferroptosis. This study aims to establish a glutamate‐induced injury model of mouse hippocampal neurons HT‐22 cells, and investigate the protective effect of ISO on the neurotoxicity of glutamate‐induced HT‐22 cells. The results showed that ISO inhibited glutamate‐induced ferroptosis of neuronal cells through nuclear factor E2‐related factor 2/glutathione peroxidase 4 (Nrf2/GPX4) signaling pathway. Pretreatment of HT‐22 cells with ISO significantly reduced glutamate‐induced cell death. Ferroptosis inhibitors have the same effect. ISO inhibited the decrease of mitochondrial membrane potential detection and the increase of iron content induced by glutamate, the increase of malondialdehyde and reactive oxygen species in cytoplasm and lipid, and protected the activities of GPx and superoxide dismutase enzymes. In addition, WB showed that glutamic acid could induce the upregulated expression of long‐chain esteryl coA synthase 4 (ACSL4) protein and the downregulated expression of SLC7A11 and GPX4 protein in HT‐22 cells, while ISO could prevent the abnormal expression of these proteins induced by glutamic acid. The nuclear translocation of Nrf2 in HT‐22 cells was increased, and the expression of downstream heme oxygenase‐1 protein was upregulated. In summary, ISO protects HT‐22 cells from glutamate‐induced ferroptosis through a novel mechanism of the Nrf2/GPX4 signaling pathway. [ABSTRACT FROM AUTHOR]

Innovative Tangyang Congou black tea, also known as Minkehong black tea (MKH), is of high quality and hence has gained a reputation on the market. In this study, standard samples of MKH were used as the research material, and the results of sensory evaluation showed that the overall quality of MKH decreased along with the downgrading. The radar chart showed a strong association between higher grades and specific aroma and taste character. Based on the detection of ultra-performance liquid chromatography–mass spectrometry (UPLC–MS) and related analysis, the content of both the ester-type catechins and non-ester catechins decreased along with the downgrading, and the details of their change trends were revealed. The content and dynamic changes in caffeine were also investigated. A total of 19 kinds of amino acids (AAs) were clustered; among them, 4 kinds of AAs, namely, Thr, Leu, Asp, and Ile, significantly contributed to the taste of the tea. Notably, the content of Thr had the highest correlation with the grade of MKH, and the correlation coefficient was 0.991 (p < 0.01). According to gas chromatography–mass spectrometry (GC–MS) detection and analysis, a total of 861 kinds of volatile compounds were detected, the aroma-active compounds in different grades were selected, and an aroma wheel of MKH was constructed. Our results found that non-volatile and volatile compounds not only contribute to defining the level of MKH standard samples but also provide a chemical basis for the measurement of flavour and quality of MKH. [ABSTRACT FROM AUTHOR]

The purpose of this trial was to evaluate the pharmacokinetics (PK), bioequivalence (BE), and safety of 2 preparations of hydroxychloroquine (200‐mg tablet) under fasting and fed conditions. A total of 180 subjects (fasting condition: n = 80; fed condition: n = 100) were randomly enrolled in this randomized, open, single‐dose, single‐cycle parallel phase Ⅰ clinical study. Under the 2 conditions, the subjects were randomly administered the test (T) or reference (R) tablet, both at a dose of 200 mg (1 tablet). Liquid chromatography–tandem mass spectrometry was used to determine the concentration of hydroxychloroquine in healthy subjects after oral administration of the T or R preparation to evaluate the PK characteristics. In this trial, the T and R preparations of hydroxychloroquine were bioequivalent under both conditions within the range of 80%–125%. No serious adverse events (SAEs) were found in the safety assessments for either condition, and all adverse events (AEs) were mild, except for 2 moderate AEs in the fed condition, indicating good safety. [ABSTRACT FROM AUTHOR]

A combination of dielectric and thermal properties is the prime factor for developing glass–ceramics for practical aspects in low-temperature co-fired ceramic technology. In this work, we report the low melting-point compositions of BaO–Al2O3–SiO2–B2O3 and BaAl2Si2O8 ceramics at 900 °C. The phase evolutions, microstructure, dielectric, and thermal expansion properties corresponding to the partial replacement of Ba2+ with alkaline earth metal ions R2+, i.e., Sr2+, Ca2+, and Mg2+ were investigated. The results indicated that, because the lattice distortion of hexacelsian structure was caused by solid solutions of substitution ions to BaAl2Si2O8 ceramics, the phase transition of hexacelsian can be gradually inhabited with the decrease of the substitution ion radius. Notably, the partial substitution of Mg2+ in the Ba2+ can completely inhibit the phase transition and promote the formation of orthorhombic celsian. By the substitution of 40 mol% of Ba2+ to Mg2+, physical properties, i.e., density of 2.22 g⋅cm−3, εr of 4.08 at 12 GHz, and tanδ of 2.7 × 10−3, are obtained. Importantly, the coefficient of thermal expansion (CTE) of 4.02 × 10−6/°C close to that of monocrystalline silicon is also successfully achieved. The new BaAl2Si2O8 ceramics with low CTE and reliable thermal stability demonstrated the potential for application in chip packaging. [ABSTRACT FROM AUTHOR]

A hydrothermal-sintering process for metakaolin-based geopolymers was exploited to immobilize simulated 137CsCl. Pollucite phase is easily formed from geopolymers containing NaOH under 200 ℃ hydrothermal conditions. An additional 1200 ℃-sintering process step not only retained the pollucite phase in the sintered geopolymers, but also increased the density of the microstructures. The leached ion fraction from the geopolymers prepared using the hybrid hydrothermal-sintering process was obviously lower than that of geopolymers prepared using only the 200 ℃ hydrothermal processing steps. Especially, the hybrid hydrothermal-sintering process lowered the Cs+ volatilization during sintering due to the presence of the pollucite phase precursor in the geopolymers. [ABSTRACT FROM AUTHOR]