Thiamine Research Articles

Early Infantile Thiamine Transporter-2 Deficiency with Epileptic Spasms—A Phenotypic Spectrum with a Novel Mutation

AbstractEpileptic seizures are a frequent feature of thiamine transporter deficiency that may present as a clinical continuum between severe epileptic encephalopathy and mixed focal or generalized seizures. Thiamine metabolism dysfunction syndrome 2 (MIM: 607483) or biotin-thiamine-responsive basal ganglia disease (BTBGD) due to biallelic pathogenic mutation in the SLC19A3 gene is a well-recognized cause of early infantile encephalopathy with a Leigh syndrome-like presentation and a lesser-known phenotype of atypical infantile spasms. We reported a 4-month-old infant who presented with progressive epileptic spasms since 1 month of age, psychomotor retardation, and lactic acidosis. Magnetic resonance imaging (MRI) revealed altered signal intensities in bilateral thalamic and basal ganglia, cerebellum, brainstem, cortical and subcortical white matter. Whole exome sequencing identified a homozygous ENST00000258403.3: c.871G > C (p.Gly291Arg) variant in the SLC19A3 gene. We elucidate the features in the proband, which were an amalgamation of both the above subtypes of the SLC19A3 associated with early infantile encephalopathy. We also highlight the features which were atypical for either “Leigh syndrome-like” or “atypical infantile spasm” phenotypes and suggest that the two separate entities can be merged as a clinical continuum. Treatment outcome with high-dose biotin and thiamine is promising. In addition, we report a novel pathogenic variant in the SLC19A3 gene.

Conferring thermotolerant phenotype to wild-type Yarrowia lipolytica improves cell growth and erythritol production.

In microbial engineering, heat stress is an important environmental factor modulating cell growth, metabolic flux distribution and the synthesis of target products. Yarrowia lipolytica, as a GARS (generally recognized as safe) nonconventional yeast, has been widely used in the food industry, especially as the host of erythritol production. Biomanufacturing economics is limited by the high operational cost of cooling energy in large-scale fermentation. It is of great significance to select thermotolerant Y. lipolytica to reduce the cooling cost and elucidate the heat-resistant mechanism at molecular level. For this purpose, we performed adaptive evolution and obtained a thermotolerant strain named Y. lipolytica BBE-18. Transcriptome analysis allows us to identify four genes in thiamine metabolism pathway that are responsible for the complicated thermotolerant phenotype. The heat-resistant phenotype was validated with the model strain Y. lipolytica Po1f by overexpression of single and combined genes. Then, conferring the thermotolerant phenotype to the wild-type Y. lipolytica BBE-17 enable the strain to produce three-times more erythritol of the control strain with 3°C higher than optimal cultivation temperature. To our knowledge, this is the first report on engineering heat-resistant phenotype to improve the erythritol production in Y. lipolytica. However, due to the increase of culture temperature, a large amount of adenosine triphosphate is consumed to ensure the life activities of Y. lipolytica which limits the potential of cell synthetic products to a certain extent. Even so, this study provides a reference for Y. lipolytica to produce other products under high temperature.

Identification and functional analysis of drought responsive lncRNAs in tea plant

Long noncoding RNAs (lncRNAs) are a class of non-coding RNAs that are more than 200 nucleotides in length. Emerging evidence suggest that lncRNAs by regulating gene expression can act as key regulators of diverse biological processes in plants. The identification of differentially expressed lncRNAs associated with drought tolerance/susceptibility is important to study and understand the complex regulation of drought responses of the tea plant. In this study, we identified 21,241 lncRNAs based on computational analysis of publicly available RNA-seq data of Camellia sinensis, among them 1395 lncRNAs were identified as drought specific. Some of these drought specific lncRNAs acts as target mimic of known mRNAs or putative targets for many already reported abiotic stress responsive microRNAs (miRNAs). One hundred and thirty two lncRNAs of tea were predicted to act as potential endogenous target mimics (eTMs) for 136 transcripts, which includes stress responsive transcription factors (TFs) such as GAMYB, RAP2–7 and MYC2. KEGG pathway analyses of the genes for which 132 lncRNAs act as eTMs showed highest number of genes in purine and thiamine metabolism pathways. This study gives an overview of the drought responsive lncRNAs and their possible functional roles in tea during drought stress conditions.

Effect of vitamins and metal ions on productivity and charge heterogeneity of IgG1 expressed in CHO cells.

Recombinant monoclonal antibodies have emerged as the most successful modality of biotherapeutics. They are primarily expressed in Chinese Hamster Ovary (CHO) cells. It is well known that post-translational modifications (PTM) contribute significantly to heterogeneity with respect to charge, glycosylation, and size. These attributes in turn impact stability, pharmacokinetics, and pharmacodynamics of the biotherapeutic product. Cell culture media components are known to significantly contribute to both cellular productivity as well as post-translational modifications. Thus, it is highly desirable to understand how media components affect product quality. This study aims to explore the impact of vitamins and metal ions on protein expression and post-translational modifications specifically charge heterogeneity. Biotin, choline chloride, D-calcium pantothenate, folic acid, pyridoxine hydrochloride, thiamine hydrochloride vitamins and Fe, Cu, Mg, Co, Zn, Mn, Ni metal ions were examined in this study. The results indicate that pyridoxine enhances productivity while Zn, Cu, Fe, Mn, and biotin impact charge heterogeneity. While, Fe, Mn and Ni enhance production of the acidic variants, Cu and biotin inhibit it. Zn reduces formation of basic variants while biotin enhances it. The results from this investigation could be used for process control so as to get consistent charge variant profile, in particular for biosimilars.

Metabolic engineering provides insight into the regulation of thiamin biosynthesis in plants.

Thiamin (or thiamine) is a water-soluble B-vitamin (B1), which is required, in the form of thiamin pyrophosphate, as an essential cofactor in crucial carbon metabolism reactions in all forms of life. To ensure adequate metabolic functioning, humans rely on a sufficient dietary supply of thiamin. Increasing thiamin levels in plants via metabolic engineering is a powerful strategy to alleviate vitamin B1 malnutrition and thus improve global human health. These engineering strategies rely on comprehensive knowledge of plant thiamin metabolism and its regulation. Here, multiple metabolic engineering strategies were examined in the model plant Arabidopsis thaliana. This was achieved by constitutive overexpression of the three biosynthesis genes responsible for B1 synthesis, HMP-P synthase (THIC), HET-P synthase (THI1), and HMP-P kinase/TMP pyrophosphorylase (TH1), either separate or in combination. By monitoring the levels of thiamin, its phosphorylated entities, and its biosynthetic intermediates, we gained insight into the effect of either strategy on thiamin biosynthesis. Moreover, expression analysis of thiamin biosynthesis genes showed the plant's intriguing ability to respond to alterations in the pathway. Overall, we revealed the necessity to balance the pyrimidine and thiazole branches of thiamin biosynthesis and assessed its biosynthetic intermediates. Furthermore, the accumulation of nonphosphorylated intermediates demonstrated the inefficiency of endogenous thiamin salvage mechanisms. These results serve as guidelines in the development of novel thiamin metabolic engineering strategies.

Transcriptomics Provides a Genetic Signature of Vineyard Site and Offers Insight into Vintage-Independent Inoculated Fermentation Outcomes.

ABSTRACTRibosomal DNA amplicon sequencing of grape musts has demonstrated that microorganisms occur nonrandomly and are associated with the vineyard of origin, suggesting a role for the vineyard, grape, and wine microbiome in shaping wine fermentation outcomes. Here, ribosomal DNA amplicon sequencing from grape musts and RNA sequencing of eukaryotic transcripts from primary fermentations inoculated with the wine yeast Saccharomyces cerevisiae RC212 were used to profile fermentations from 15 vineyards in California and Oregon across two vintages. These data demonstrate that the relative abundance of fungal organisms detected by ribosomal DNA amplicon sequencing correlated with neither transcript abundance from those same organisms within the RNA sequencing data nor gene expression of the inoculated RC212 yeast strain. These data suggest that the majority of the fungi detected in must by ribosomal DNA amplicon sequencing were not active during the primary stage of these inoculated fermentations and were not a major factor in determining RC212 gene expression. However, unique genetic signatures were detected within the ribosomal DNA amplicon and eukaryotic transcriptomic sequencing that were predictive of vineyard site and region. These signatures included S. cerevisiae gene expression patterns linked to nitrogen, sulfur, and thiamine metabolism. These genetic signatures of site offer insight into specific environmental factors to consider with respect to fermentation outcomes and vineyard site and regional wine characteristics.IMPORTANCE The wine industry generates billions of dollars of revenue annually, and economic productivity is in part associated with regional distinctiveness of wine sensory attributes. Microorganisms associated with grapes and wineries are influenced by region of origin, and given that some microorganisms play a role in fermentation, it is thought that microbes may contribute to the regional distinctiveness of wine. In this work, as in previous studies, it is demonstrated that specific bacteria and fungi are associated with individual wine regions and vineyard sites. However, this work further shows that their presence is not associated with detectable fungal gene expression during the primary fermentation or the expression of specific genes by the inoculate Saccharomyces cerevisiae strain RC212. The detected RC212 gene expression signatures associated with region and vineyard site also allowed the identification of flavor-associated metabolic processes and environmental factors that could impact primary fermentation outcomes. These data offer novel insights into the complexities and subtleties of vineyard-specific inoculated wine fermentation and starting points for future investigations into factors that contribute to regional wine distinctiveness.

Thiamine in Lipid Systems vs. the Antioxidant Activity of Epigallocatechin Gallate and Caffeine

The aim of this study was to determine correlations between the concentration of thiamine hydrochloride or thiamine pyrophosphate and the antioxidant activity of epigallocatechin gallate (EGCG) and caffeine, as well as thiamine stability. The study was conducted in model systems. Oxidation degree indices of soybean oil (peroxide value and anisidine value LAN) and concentrations of total thiamine were determined. To compare the dynamics of the changes in thiamine content during storage, half-life T1/2 was determined. There was a strong correlation between the stability of thiamine and the stability of the oil. Thiamine was particularly sensitive to secondary oxidation products. Higher losses of thiamine introduced in the form of thiamine pyrophosphate were found (4–6%). The addition of tea components increased fat stability and thus reduced thiamine losses. The dynamics of thiamine loss were found to be lower with EGCG than caffeine. The antioxidant activity of these components was significantly reduced when the content of thiamine (1.0–20.0 mg/100 g) was higher than the natural level in foods. In order to maintain thiamine stability and the high activity of the active tea ingredients, it is necessary to consider their simultaneous addition to the systems in concentrations that limit their interactions.

Application of CTAB-Coated Magnetic Nanoparticles for Solid-Phase Extraction of Thiamine Hydrochloride from Pharmaceutical Formulations and Urine Samples

This study investigated an efficient and low-cost magnetic solid-phase microextraction engaged with spectrophotometry method for extraction and determination of thiamine hydrochloride (THY) in pharmaceutical and urine samples. Adsorption and desorption of red azo dye findings from THY coupling with the diazotized drug compound (sulfadimidine sodium) in an alkaline medium were established by magnetic iron oxide nanoparticles (MNPs) coated with cetyltrimethylammonium bromide (CTAB). The extracted azo dye product was measured spectrophotometrically at λmax of 510 nm. The azo dye removal efficiency of modified MNPs was assessed by investigating several conditions, such as the concentration of reagents, surfactant amount, adsorbent amount, pH of the solution, contact time, sample volume, and desorption factors. Under the optimized conditions, the removal percentage of the azo dye of 98% with good linearity over the investigated concentrations range 0.1–5 μg/mL was obtained. Limits of detection and quantification were 0.053 and 0.18 μg/mL, respectively, with the relative standard deviation (RSD) better than 3%. The method was applied to estimate THY in different matrices using the CTAB-coated MNPs, within an extraction time of 10 min.

Ensemble Switching Unveils a Kinetic Rheostat Mechanism of the Eukaryotic Thiamine Pyrophosphate Riboswitch.

Thiamine pyrophosphate (TPP) riboswitches regulate thiamine metabolism by inhibiting the translation of enzymes essential to thiamine synthesis pathways upon binding to thiamine pyrophosphate in cells across all domains of life. Recent work on the Arabidopsis thaliana TPP riboswitch suggests a multistep TPP binding process involving multiple riboswitch configurational ensembles and Mg2+ dependence underlies the mechanism of TPP recognition and subsequent transition to the expression-inhibiting state of the aptamer domain followed by changes in the expression platform. However, details of the relationship between TPP riboswitch conformational changes and interactions with TPP and Mg2+ in the aptamer domain constituting this mechanism are unknown. Therefore, we integrated single-molecule multiparameter fluorescence and force spectroscopy with atomistic molecular dynamics simulations and found that conformational transitions within the aptamer domain's sensor helices associated with TPP and Mg2+ ligand binding occurred between at least five different ensembles on timescales ranging from µs to ms. These dynamics are orders of magnitude faster than the 10 sec-timescale folding kinetics associated with expression-state switching in the switch helix. Together, our results show that a TPP and Mg2+ dependent mechanism determines dynamic configurational state ensemble switching of the aptamer domain's sensor helices that regulate the switch helix's stability, which ultimately may lead to the expression-inhibiting state of the riboswitch. Additionally, we propose that two pathways exist for ligand recognition and that this mechanism underlies a kinetic rheostat-like behavior of the Arabidopsis thaliana TPP riboswitch.

Gut Microbiota in Untreated Diffuse Large B Cell Lymphoma Patients.

Intestinal microecology plays an important role in the development and progression of hematological malignancies. However, characteristics of gut microbiota in diffuse large B cell lymphoma (DLBCL) have not been reported. The microbiota composition of fecal samples from 25 untreated DLBCL patients and 26 healthy volunteers was examined by 16S rRNA gene sequencing. On α-diversity analysis, there was no significant difference in species diversity and abundance between the two groups. However, a significant difference was observed on β-diversity analysis. The intestinal microbiota in patients with DLBCL showed a continuous evolutionary relationship, which progressed from phylum, proteobacteria, to genus, Escherichia-Shigella. Their abundance was significantly higher than that of the control group. At the genus level, Allisonella, lachnospira, and Roseburia were more abundant in patients with DLBCL than in the control group. Functional prediction by PICRUSt indicated that thiamine metabolism and phenylalanine, tyrosine, and tryptophan biosynthesis were significantly lower in the DLBCL group than in the control group. In conclusion, our results clearly demonstrate that the gut microbiota was changed significantly in DLBCL. The study highlights fundamental differences in the microbial diversity and composition of patients with DLBCL and paves the way for future prospective studies and microbiome-directed interventional trials to improve patient outcomes.

Another Trial Shows No Benefit of Vitamin C, Thiamine, and Hydrocortisone in Sepsis

In 2017, treating patients who had sepsis and septic shock with vitamin C, thiamine, and glucocorticoids became the hottest topic of discussion in

Bioinformatic Analysis of Exosomal MicroRNAs of Cerebrospinal Fluid in Ischemic Stroke Rats After Physical Exercise.

Physical exercise is beneficial to the structural and functional recovery of post-ischemic stroke, but its molecular mechanism remains obscure. Herein, we aimed to explore the underlying mechanism of exercise-induced neuroprotection from the perspective of microRNAs (miRNAs). Adult male Sprague-Dawley (SD) rats were randomly distributed into 4 groups, i.e., the physical exercise group with the transient middle cerebral artery occlusion (tMCAO) surgery (PE-IS, n = 28); the physical exercise group without tMCAO surgery (PE, n = 6); the sedentary group with tMCAO surgery (Sed-IS, n = 28); and the sedentary group without tMCAO surgery (Sed, n = 6). Notably, rats in the PE-IS and PE groups were subjected to a running exercise for 28days while rats in the Sed-IS and Sed groups received no exercise training. After long-term exercise, exosomal miRNAs of cerebrospinal fluid (CSF) were analyzed using high-throughput sequencing. Furthermore, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis were employed for the differentially expressed miRNAs. Physical exercise improved the neurological function and attenuated the lesion expansion after stroke. In total, 41 differentially expressed miRNAs were screened for the GO and KEGG analysis. GO enriched terms were associated with the central nervous system, including cellular response to retinoic acid, vagus nerve morphogenesis, cellular response to hypoxia, dendritic cell chemotaxis, cell differentiation, and regulation of neuron death. Besides, these differentially expressed miRNAs were linked to the pathophysiological process of stroke, including axon guidance, NF-kappa B signaling pathway, thiamine metabolism, and MAPK signaling pathway according to KEGG analysis. In summary, exercise training significantly alleviated the neurological damage at both functional and structural levels. Moreover, the differentially expressed miRNAs regulating multiple signal pathways were potentially involved in the neuroprotective effects of physical exercise. Therefore, these miRNAs altered by physical exercise might represent the therapeutic strategy for cerebral ischemia.

Pumpkin, Cauliflower and Broccoli as New Carriers of Thiamine Compounds for Food Fortification.

The aim of the study is to explore the possibility of vegetables being used as carriers of thiamine. The influence of carrier type (thiamine hydrochloride—TCh and thiamine pyrophosphate—TP) for the thiamine stability were investigated. Two varieties of pumpkin, Muscat and Hokkaido, as well as Cauliflower and Broccoli, were used as a matrix for the thiamine applied. The impregnated and freeze-dried vegetables were stored (230 days) with changing access to light (access to and restriction of light) and temperature (21 °C and 40 °C). The analyzed carriers were also used in the production of gnocchi dumplings. The content of thiamine was analyzed using the thiochromium method. In the study, consumer tests (n = 199) and sensory profiling were used to assess the impact of thiamine carriers on the sensory quality of gnocchi dumplings. It was found that the introduction of dried vegetables at the level of 30% allows for high sensory desirability of analyzed products, as well as suggesting the possibility of their frequent consumption. Such a product could potentially become an alternative to pork meat as a good source of thiamine. However, it should be noted that the thiamine losses may occur during the storage of dried vegetables and their culinary preparation.

Physicochemical studies on vitamins B1, B3, B6 and C in aqueous magnesium chloride solutions at different temperatures (288.15–318.15) K and at pressure (101.3) kPa

Vitamins are the precursors of many coenzymes essential for biocatalysts and their deficiency leads to diseases in masses. The vitamins are very fragile and can easily be destroyed with change external atmosphere. Electrolytes are inherent constituents of cytoplasm and are required in variety of biochemical functions. The interactions occurring between, solute-cosolute and solvent can be inferenced and interpreted from thermodynamic and transport studies effectively which will help in interpreting the mechanism of vitamins in solution phase. In the present study apparent molar volume ϕV, and viscosity B-coefficient B, have been determined for l-ascorbic acid (Vit.C), nicotinic acid (Vit.B3), thiamine hydrochloride (HCl salt of Vit. B1) and pyridoxine hydrochloride (HCl salt of Vit. B6) in aqueous magnesium chloride solutions (mB = 0.1 to 0.5 mol∙kg−1) over the temperature range (288.15–318.15) K at pressure (101.3) kPa. The partial molar volume of transfer, ∆trϕVo, and viscosity B-coefficient of transfer, ∆trB, for these compounds from water to aqueous solutions of magnesium chloride have been determined from the corresponding data. First (∂ϕVo/ ∂T) P and second (∂2ϕVo/ ∂T2)P, derivative of ϕVo and dB/dT, values have been calculated. B/ϕVo ratio, activation free energy of viscous flow of vitamins ∆μ2o#, and other parameters have also been calculated. Both volumetric and viscometric studies suggest the presence of complex interactions at lower concentrations, but the role of cosolute becomes decisive at higher concentrations. The dB/dT values and activation parameters (∆S2o#, ∆H2o#) values suggest that l-ascorbic acid, thiamine hydrochloride and pyridoxine hydrochloride show bond making tendencies with magnesium chloride while nicotinic acid shows comparatively less affinity with magnesium chloride.

Generation of new salt-tolerant wheat lines and transcriptomic exploration of the responsive genes to ethylene and salt stress

Wheat (Triticum aestivum L.) is one of the most important staple crops. Most of wheat varieties are sensitive to salt stress, which is a major limitation for wheat production. To develop salt-tolerant wheat varieties for sustainable grain production, we used ethylmethylsulfonate to mutagenize over 90,000 seeds of the wheat cultivar Luyuan502. A total of 2000 salt-tolerant lines were identified after screening the plants in a salinized field. We further analyzed ethylene sensitivity, salt related physiological changes, and preliminary crop yield of the selected plants. We found 11 salt-tolerant lines exhibiting ethylene insensitivity and high grain production. Transcriptome analysis revealed 3278 differently expressed genes (DEGs) in the selected mutants, including the ones encoding CABs, PERs/PODs, BGLUs, CYP707s, and ZEPs. Most of DEGs may be involved in photosynthesis, biosynthesis of secondary metabolites, cyanoamino acid metabolism, carotenoid biosynthesis, thiamine metabolism, and cutin, suberine and wax biosynthesis pathways. In addition, 9 novel ETHYLENE RESPONSE FACTORs (ERFs) were identified and analyzed in the mutants. These ERFs may play critical roles in ethylene response and salt tolerance. The mutant lines with decreased ethylene sensitivity exhibited enhanced salt tolerance, suggesting that ethylene sensitivity was closely related with salt tolerance.

Bioinspired Optimization of Germination Nutrients Based on Lactuca sativa Seedling Root Traits as Influenced by Seed Stratification, Fortification and Light Spectrums

Ecophysiological stimulators directly affect root morphology, especially in the embryonic stage. To enhance crop germination, an understanding of the root traits under abiotic inducers is needed. In this study, the combined impacts of white and red-blue light spectrums, cold stratification, and seed fortification involving various concentrations of bioactive chemicals namely simple nutrient addition program solution, gibberellic acid, α-naphthaleneacetic acid with thiamine hydrochloride were evaluated on loose-leaf lettuce (Lactuca sativa var. Altima) seedling root architecture. The growth-promoting effects of these nutrients varied the growth rate and morphology of roots which are immediately shown during the radicle development. Integrated computer vision and computational intelligence were employed for phytomorphological signatures extraction of seedlings that were cultivated in a customized modulable spectrum experimental chamber (MSPEC). Root phenotype model was developed using graph-cut segmentation and region properties, and the ideal germination nutrient concentration was optimized using bioinspired models with firefly algorithm optimal result of 204.1 mg/L for nitrate, 238.15 mg/L for phosphate, and 158.08 mg/L for potassium. It was verified that lettuce seedlings can endure highly concentrated nutrients, however, it is more sensitive to phosphate as this macronutrient significantly promotes root growth with the increased whorl number on white light spectrum exposure with cold stratification.

Kale Attenuates Inflammation and Modulates Gut Microbial Composition and Function in C57BL/6J Mice with Diet-Induced Obesity.

Kale (Brassica oleracea var. acephala) is a vegetable common in most cultures but is less studied as a functional food compared to other cruciferous vegetables, such as broccoli. We investigated the effect of supplementing a high-fat diet (HFD) with kale (HFKV) in C57BL/6J mice. We particularly explored its role in metabolic parameters, gut bacterial composition and diversity using 16S rRNA sequencing, systematically compared changes under each phylum and predicted the functional potential of the altered bacterial community using PICRUSt2. Like other cruciferous vegetables, kale attenuated HFD-induced inflammation. In addition, kale modulated HFD-induced changes in cecal microbiota composition. The HFD lowered bacterial diversity, increased the Firmicutes: Bacteroidetes (F/B) ratio and altered composition. Specifically, it lowered Actinobacteria and Bacteroidetes (Bacteroidia, Rikenellaceae and Prevotellaceae) but increased Firmicutes (mainly class Bacilli). Kale supplementation lowered the F/B ratio, increased both alpha and beta diversity and reduced class Bacilli and Erysipelotrichi but had no effect on Clostridia. Within Actinobacteria, HFKV particularly increased Coriobacteriales/Coriobacteriaceae about four-fold compared to the HFD (p < 0.05). Among Bacteroidia, HFKV increased the species Bacteroides thetaiotaomicron by over two-fold (p = 0.05) compared to the HFD. This species produces plant polysaccharide digesting enzymes. Compared to the HFD, kale supplementation enhanced several bacterial metabolic functions, including glycan degradation, thiamine metabolism and xenobiotic metabolism. Our findings provide evidence that kale is a functional food that modulates the microbiota and changes in inflammation phenotype.

Light-responsive Au nanoclusters with oxidase-like activity for fluorescent detection of total antioxidant capacity

A fluorescent assay for total antioxidant capacity (TAC) detection based on the light-responsive oxidase-like activity of bovine serum albumin-stabilized gold nanoclusters (BSA-AuNCs) has been developed. Thiamine (TH) as the peroxidase substrate usually works at alkaline conditions and thus limits its practical applications. Here, by utilization the light-responsive oxidase-like activity of BSA-AuNCs, TH is oxidized to fluorescent thiochrome under neutral condition in two minutes due to the single oxygen generated by BSA-AuNCs upon light irradiation. After the introduction of antioxidants into the BSA-AuNCs-TH system, the formation of thiochrome is inhibited resulting in the fluorescence decrease. On the basis of the above facts, BSA-AuNCs-TH-based assay has been fabricated and applied successfully to detect antioxidants and the TAC of vitamin C tablets as well as some commercial fruit juice with satisfied results. This work may provide novel insights into developing light-responsive nanozymes-based fluorescent assays.

Thiamine: a key nutrient for yeasts during wine alcoholic fermentation.

Alcoholic fermentation is a crucial step of winemaking, during which yeasts convert sugars to alcohol and also produce or biotransform numerous flavour compounds. In this context, nutrients are essential compounds to support yeast growth and ultimately ensure complete fermentation, as well as optimized production of flavour compounds over that of off-flavour compounds. In particular, the vitamin thiamine not only plays an essential cofactor role for several enzymes involved in various metabolic pathways, including those leading to the production of wine-relevant flavour compounds, but also aids yeast survival via thiamine-dependent stress protection functions. Most yeast species are able to both assimilate exogenous thiamine into the cell and synthesize thiamine de novo. However, the mechanism and level of thiamine accumulation depend on several factors. This review provides an in-depth overview of thiamine utilization and metabolism in the model yeast species Saccharomyces cerevisiae, as well as the current knowledge on (1) the intracellular functions of thiamine, (2) the balance between and regulation of uptake and synthesis of thiamine and (3) the multitude of factors influencing thiamine availability and utilization. For the latter, a particular emphasis is placed on conditions occurring during wine fermentation. The adequacy of thiamine concentration in grape must to ensure successful fermentation is discussed together with the effect of thiamine concentration on fermentation kinetics and on wine sensory properties. This knowledge may serve as a resource to optimise thiamine concentrations for optimal industrial application of yeasts. KEY POINTS: • Thiamine uptake is preferred over biosynthesis and is transcriptionally repressed. • Multiple factors affect thiamine synthesis, availability and uptake for wine yeast. • Thiamine availability impacts fermentation kinetics and wine's sensory properties.

Nutritional potential of Solanum nigrum linn berries grown in home garden

Background: Solanum nigrum Linn is an annual herbaceous medicinal plant which can be cultivated in a natural setting. Normally this plant reaches a height of 35–100 cm. The flowers petals are greenish or whitish with bright yellow anthers. Black or purple color berries grown in bunches are noticed in this type of plants. Leaves, raw and ripe berries are consumed in different regions with a different culinary style. Aim and Objective: The present study was aimed to analyze the nutrient content of the dried berries cultivated in a home garden. Materials and Methods: Matured berries were harvested, shade dried and stored in air tight containers. Proximate principles, mineral, vitamin and phytochemical constituents of the dried berries were analyzed using standard procedures such as AOAC, inductively coupled plasma optical emission spectrometry, liquid chromatography-mass spectrometry and spectrophotometer methods. Results: The study findings revealed that moisture (10.27%), ash (6.68%), fiber (1.4%), carbohydrate (40.4%), protein (3.86%) and fat (2.55%) were present in the sample. Energy content was found to be 186 kcal/100 g. Mineral analysis indicated that Ca (32 mg), Fe (0.56 mg), Al (0.42 mg), Cu (0.25 mg) and zinc were below detection limit per 100 g. Thiamine hydrochloride (0.37 mg), Riboflavin (0.24 mg), niacinamide (0.37 mg), pyridoxine (0.26 mg), folic acid bile-duct ligated, Vitamin C (5.42 mg) and beta carotene (7.52 mg) were present per 100 g of the dried berries. Phytochemical analysis revealed the presence of bioactive compounds such as alkaloids (3.3%), tannins (1.3%), saponins (2.9%). Conclusion: The findings focus on the nutritional attributes of the herb which can be utilized in our household.