Application of lactic acid fermentation for enhancement of flavonoid bioavailability and functional properties of tea and soy phenolic extract

In recent decades, tremendous attention has been placed on phenolic compounds, due to their multiple health benefits and ubiquity in diet. Tea and soymilk, two of the most popular beverages worldwide, are rich in dietary flavonoids, with flavan-3-ols and isoflavones being the major contributors, respectively. However, the chemical instability and poor bioavailability of flavonoids pose controversies over their bioactivity and bioefficacy. In view of the potential of lactic acid bacteria (LAB) and bifidobacteria in improving functional properties of food products and their phenolic-metabolizing capability, this work aimed to enhance flavonoid bioavailability and functional properties of tea extract (TE) and soymilk by lactic acid fermentation. Satisfactory survival and metabolic activity of lactic acid-fermenting bacteria in phenolic-rich environment are prerequisites to enhancing bioavailability and bioactivities of phenolic extracts. First part of the present work examined effects of phenolic extract supplementation on viability, cell membrane characteristics and metabolic activities of selected LAB/bifidobacteria and foodborne pathogens. Results indicated that the effects were both strain and concentration-dependent. Altered cell membrane components resulting from TE supplementation led to changes in surface hydrophobicity of LAB and FT-IR spectra further further indicated modifications to membrane fatty acids (FAs), proteins and cell wall polysaccharides. GC-MS analyses of FA composition of Bifidobacterium cells revealed significant decreases in unsaturated to saturated FA ratios upon TE treatment, in addition to marked changes in the abundance of major phospholipids as studied by HPTLC. Phenolic extracts with or without lactic acid fermentation were also applied to pathogenic strains to evaluate anti-microbial and anti-adhesive activities. Results from broth-dilution and agar diffusion assays suggested more evident inhibitory effect on Gram-positive than Gram-negative bacteria from TE but comparative effect from soy extract on all bacteria. Fermented samples exhibited significantly higher anti-microbial and anti-adhesive effects compared with the original extracts. Following the examination on bacterial characteristics, effects of bacterial fermentation on flavonoid stability, phenolic composition, antioxidant capacity and cellular absorptivity of phenolic extracts were investigated. Lastly, flavonoid bioavailability, overall anti-oxidative effectiveness and defense mechanisms of fermented black tea extract were studied in Balb/c mice. HPLC analyses indicated that stepwise fermentation efficiently stabilized tea flavonoids (TFLs) during food processing and storage. Data from LC-MS/MS elucidated structural modification of TFLs by Lactobacillus strains and enhanced bioavailability as studied in Caco-2 epithelial monolayers and in mice. Additionally, fermented TEs were more effective in ameliorating H2O2–induced oxidative damage to mitochondria and DNA in human colonocytes as determined by flow cytometry and Comet assay, respectively. Protection against oxidative damage induced by 8-week D-galactose overdose in mice was conferred by both fermented and non-fermented black tea diets as demonstrated by the restored plasma antioxidant capacity, attenuated lipid peroxidation and elevated glutathione levels. Western blot analyses further implied that modulation of glutathione-dependent enzyme systems could be the underlying protective mechanism. This work suggested promising perspectives in enhancing flavonoid bioavailability and combating oxidative stress via dietary interventions. Concomitant use of dietary phenolic extract and lactic acid fermentation may be applied in developing functional foods as healthy dietary supplements.published_or_final_versionBiological SciencesDoctoralDoctor of Philosoph

Characterization of the Chloroplast Genome of Argyranthemum frutescens and a Comparison with Other Species in Anthemideae

Argyranthemum frutescens, which belongs to the Anthemideae (Asteraceae), is widely cultivated as an ornamental plant. In this study, the complete chloroplast genome of A. frutescens was obtained based on the sequences generated by Illumina HiSeq. The chloroplast genome of A. frutescens was 149,626 base pairs (bp) in length, containing a pair of inverted repeats (IR, 24,510 bp) regions separated by a small single-copy (SSC, 18,352 bp) sequence and a large single-copy (LSC, 82,254 bp) sequence. The genome contained 132 genes, consisting of 85 coding DNA sequences, 37 tRNA genes, and 8 rRNA genes, with nineteen genes duplicated in the IR region. A comparison chloroplast genome analysis among ten species from the tribe of Anthemideae revealed that the chloroplast genome size varied, but the genome structure, gene content, and oligonucleotide repeats were highly conserved. Highly divergent regions, e.g., ycf1, trnK-psbK, petN-psbM intronic, were detected. Phylogenetic analysis supported Argyranthemum as a separate genus. The findings of this study will be helpful in the exploration of the phylogenetic relationships of the tribe of Anthemideae and contribute to the breeding improvement of A. frutescens

A Coil Constant Calibration Method Based on the Phase-Frequency Response of Alkali Atomic Magnetometer

Abstract We propose an in-situ method to calibrate the coil constants of the optical atomic magnetometer. This method is based on measuring the Larmor precession of spin polarized alkali metal atoms and has been demonstrated on a K-Rb hybrid atomic magnetometer. Oscillation fields of different frequencies are swept on the transverse coil. By extracting the resonance frequency through phase-frequency analysis of electron spin projection, the coil constants are calibrated to be 323.1 ± 0.28 nT/mA, 108 ± 0.04 nT/Ma, and 185.8 ± 1.03 nT/mA along the X, Y, and Z directions, respectively

Origin and Fate of Acrolein in Foods

Acrolein is a highly toxic agent that may promote the occurrence and development of various diseases. Acrolein is pervasive in all kinds of foods, and dietary intake is one of the main routes of human exposure to acrolein. Considering that acrolein is substantially eliminated after its formation during food processing and re-exposed in the human body after ingestion and metabolism, the origin and fate of acrolein must be traced in food. Focusing on molecular mechanisms, this review introduces the formation of acrolein in food and summarises both in vitro and in vivo fates of acrolein based on its interactions with small molecules and biomacromolecules. Future investigation of acrolein from different perspectives is also discussed

Circular RNA cTFRC acts as the sponge of MicroRNA-107 to promote bladder carcinoma progression

Abstract Background Circular RNA (circRNA) represents a broad and diverse endogenous RNAs that can regulate gene expression in cancer. However, the regulation and function of bladder cancer (BC) circRNAs remain largely unknown. Methods Here we generated circRNA microarray data from three BC tissues and paired non-cancerous matched tissues, and detected circular RNA-cTFRC up-regulated and correlated with tumor grade and poor survival rate of BC patients. We subsequently performed functional analyses in cell lines and an animal model to support clinical findings. Mechanistically, we demonstrated that cTFRC could directly bind to miR-107 and relieve suppression for target TFRC expression. Results We detected circular RNA-cTFRC up-regulated and correlated with tumor grade and poor survival rate of BC patients. Knock down of cTFRC inhibited invasion and proliferation of BC cell lines in vitro and tumor growth in vivo. Furthermore, the expression of cTFRC correlated with TFRC and negatively correlated with miR-107 both in BC cell lines and BC clinical samples. In addition, up-regulation of cTFRC promoted TFRC expression and contributed to an epithelial to mesenchymal transition phenotype in BC cells. Finally, we found that cTFRC acts as a competing endogenous RNA (ceRNA) for miR-107 to regulate TFRC expression. Conclusions cTFRC may exert regulatory functions in BC and may be a potential marker of BC diagnosis or progression

Quantifying the heterogeneous impacts of the urban built environment on traffic carbon emissions: New insights from machine learning techniques

The configuration of the urban built environment is critical for promoting sustainability and achieving carbon neutrality. However, existing studies mostly use linear and spatial econometric models to investigate the relationship between urban built environments and traffic carbon dioxide (CO2) emissions, in-depth studies exploring the heterogeneous impacts of related features on traffic CO2 emission by interpretive machine learning models are scarce. Hence, we extract four dimensionless features to depict the size, compactness, irregularity, and isolation of built-up areas, and road network-related features (i.e., average cluster coefficient, road topological density, and road geometric density), respectively. Subsequently, we develop an interpretive machine learning framework based on the extracted features related to the urban built-up areas and road networks. The interpretive results of the proposed framework uncover that urban morphological features, especially population density (POP), GDP per capita (GDPpc), and urban physical compactness (UPC), have a heterogeneous impact on the per capita traffic emission (PCCE) across different cities. GDPpc is more like a linear relationship with PCCE, and UPC has a significant influence on PCCE when its value is between 62% and 78%. Our results also reveal the nonlinear relationships and interactive effects between these features, providing the implications of urban morphological planning and carbon emission reduction.Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Transport and Plannin

Hope and challenge: Precision medicine in bladder cancer

Abstract Bladder cancer (BC) is a complex disease and could be classified into nonmuscle‐invasive BC (NMIBC) or muscle‐invasive BC (MIBC) subtypes according to the distinct genetic background and clinical prognosis. Until now, the golden standard and confirmed diagnosis of BC is cystoscopy and the major problems of BC are the high rate of recurrence and high costs in the clinic. Recent molecular and genetic studies have provided perspectives on the novel biomarkers and potential therapeutic targets of BC. In this article, we provided an overview of the traditional diagnostic approaches of BC, and introduced some new imaging, endoscopic, and immunological diagnostic technology in the accurate diagnosis of BC. Meanwhile, the minimally invasive precision treatment technique, immunotherapy, chemotherapy, gene therapy, and targeted therapy of BC were also included. Here, we will overview the diagnosis and therapy methods of BC used in clinical practice, focusing on their specificity, efficiency, and safety. On the basis of the discussion of the benefits of precision medicine in BC, we will also discuss the challenges and limitations facing the non‐invasive methods of diagnosis and precision therapy of BC. The molecularly targeted and immunotherapeutic approaches, and gene therapy methods to BC treatment improved the prognosis and overall survival of BC patients

Mechanistic insights into zearalenone-accelerated colorectal cancer in mice using integrative multi-omics approaches

202310 bcvcVersion of RecordOthersANCOM-BC, (RT-qPCR); Guangdong Basic and Applied Research Major Program; PolyU Start-up Fund; Shenzhen Basic Research Program; ZEA; City University of Hong KongPublishe