•Proof of concept of growth on wheat bran for four microorganisms.•Selection of plant biomass-consuming microorganisms can be performed using carbohydrates and proteases specific ...databases.•Degradation of wheat bran can be followed with Fourier Transform Infra-Red spectroscopy coupled to enzyme activity analysis.•Carotenoids, flexirubin and canthaxanthin can be produced from a cheap and renewable carbon source.
Pigments are compounds with highly diverse structures and wide uses, which production is increasing worldwide. An eco-friendly method of bioproduction is to use the ability of some microorganisms to ferment on renewable carbon sources. Wheat bran (WB) is a cheap and abundant lignocellulosic co-product of low recalcitrance to biological conversion. Microbial candidates with theoretical ability to degrade WB were first preselected using specific databases. The microorganisms were Ashbya gossypii (producing riboflavin), Chitinophaga pinensis (producing flexirubin), Chromobacterium vaccinii (violacein) and Gordonia alkanivorans (carotenoids). Growth was shown for each on minimal salt medium supplemented with WB at 5 g.L−1. Activities of the main enzymes consuming WB were measured, showing leucine amino-peptidase (up to 8.45 IU. mL−1) and β-glucosidase activities (none to 6.44 IU. mL−1). This was coupled to a FTIR (Fourier Transform Infra-Red) study of the WB residues that showed main degradation of the WB protein fraction for C. pinensis, C. vaccinii and G. alkanivorans. Production of the pigments on WB was assessed for all the strains except Ashbya, with values of production reaching up to 1.47 mg.L−1. The polyphasic approach used in this study led to a proof of concept of pigment production from WB as a cheap carbon source.
Through recurrent bouts synchronous with the hair cycle, quiescent melanocyte stem cells (McSCs) become activated to generate proliferative progeny that differentiate into pigment-producing ...melanocytes. The signaling factors orchestrating these events remain incompletely understood. Here, we use single-cell RNA sequencing with comparative gene expression analysis to elucidate the transcriptional dynamics of McSCs through quiescence, activation, and melanocyte maturation. Unearthing converging signs of increased WNT and BMP signaling along this progression, we endeavored to understand how these pathways are integrated. Employing conditional lineage-specific genetic ablation studies in mice, we found that loss of BMP signaling in the lineage leads to hair graying due to a block in melanocyte maturation. We show that interestingly, BMP signaling functions downstream from activated McSCs and maintains WNT effector, transcription factor LEF1. Employing pseudotime analysis, genetics, and chromatin landscaping, we show that following WNT-mediated activation of McSCs, BMP and WNT pathways collaborate to trigger the commitment of proliferative progeny by fueling LEF1- and MITF-dependent differentiation. Our findings shed light upon the signaling interplay and timing of cues that orchestrate melanocyte lineage progression in the hair follicle and underscore a key role for BMP signaling in driving complete differentiation.
Pigment production plants are among the most polluting industries due to their high-water consumption and complex releases. The current work investigates the removal efficiency of sodium chloride ...(NaCl), sodium acetate (C2H3NaO2), and acetic acid (CH3COOH), and also the permeate flux of a small-batch OPM-K membrane using reverse osmosis (RO) pilot plant at various concentrations and pressures. At 0.034 M and applied pressure of 30 bar, the results showed that the maximum sodium chloride removal and permeate flow were 93.4% and 8.3 × 10−6 m/s, respectively. When the feed concentration was increased to 0.17 M, the maximum removal efficiency and permeate flow were 88.5% and 4.7 × 10−6 m/s, respectively. In addition, acetic acid has a minimum removal efficiency of 76.2% at 0.062 M and 20 bar applied pressure, while sodium acetate has a minimum permeate flow of 2.8 × 10−6 at 0.061 M and 20 bar. To conclude, the results proved RO membrane's high removal efficiency and permeate flux at low salt concentrations. It should also be noted that RO would be more suitable for the retention of NaCl, C2H3NaO2, and CH3COOH, the three components with the highest concentration in wastewater discharged from pigment production plants.
Navicula incerta is a marine microalga distributed in Baja California, México, commonly used in aquaculture nutrition, and has been extended to human food, biomedical, and pharmaceutical industries ...due to its high biological activity. Therefore, the study aimed to optimize culture conditions to produce antioxidant pigments. A central composite experimental design and response surface methodology (RSM) was employed to analyze the best culture conditions. The medium (nitrogen-deficient concentrations), salinity (PSU = Practical Salinity Unity g/kg), age of culture (days), and solvent extraction (ethanol, methanol, and acetone) were the factors used for the experiment. Chlorophyll a (Chl a) and total carotenoids (T-Car), determined spectroscopically, were used as the response variables. The antioxidant capacity was evaluated by DPPH• and ABTS•+ radical inhibition, FRAP, and anti-hemolytic activity. According to the overlay plots, the optimum growth conditions for Chl a and T-Car production were the following conditions: medium = 0.44 mol·L-1 of NaNO3, salinity = 40 PSU, age of culture: 3.5 days, and solvent = methanol. The pigment extracts obtained in these optimized conditions had high antioxidant activity in ABTS•+ (86.2–92.1% of inhibition) and anti-hemolytic activity (81.8–96.7% of hemolysis inhibition). Low inhibition (33–35%) was observed in DPPH•. The highest value of FRAP (766.03 ± 16.62 μmol TE/g) was observed in the acetonic extract. The results demonstrated that RSM could obtain an extract with high antioxidant capacity with potential applications in the biomedical and pharmaceutical industry, which encourages the use of natural resources for chemoprevention of chronic-degenerative pathologies.
Scandium (Sc), declared a critical raw material in the European Union (EU), could face further supply issues as the EU depends almost entirely on imports from China, Russia, and Ukraine. In this ...study, a tandem nanofiltration-solvent extraction procedure for Sc recovery from titania (TiO
) acid waste was piloted and then augmented by antisolvent crystallization. The new process, comprising advanced filtration (hydroxide precipitation, micro-, ultra-, and nanofiltration), solvent extraction, and antisolvent crystallization, was assessed in relation to material and energy inputs and benchmarked on ScF
production. From ∼1 m
of European acid waste containing traces of Sc (81 mg L
), ∼13 g of Sc (43% yield, nine stages) was recovered as (NH
)
ScF
with a purity of approximately 95%, demonstrating the technical feasibility of the approach. The production costs per kilogram of ScF
were lower than reported market prices, which underscores a competitive process at scale. Although a few technical bottlenecks (e.g., S/L separation and electricity consumption) need to be overcome, combining advanced filtration with solvent extraction and antisolvent crystallization promises a future supply of this critical raw material from European secondary sources.
ABSTRACTObjectives: The study was aimed at isolating and identifying violacein-producing bacteria from the different ecosystems.Methods: The violet color pigment (violacein) producing bacteria was ...isolated and identified morphologically and genomically.Results: A total of ten bacterial Chromobacterium sp. were isolated from different sources such as soil and water. The violacein productivity wasscreened by the total isolates and the selected two strains were identified as Chromobacterium violaceum CV4 and Chromobacterium vaccinii CV5 bymorphologically and genomically.Conclusion: In the present study, the two isolate was morphologically and genomically identified as Chromobacterium violaceum CV4 andChromobacterium vaccinii CV5, last one was found to be the novel strain from natural sources which possess a high violacein producing capability.Keywords: Chromobacterium sp., Violacein, Pigment production.
Pseudomonas aeruginosa, one of the most notorious organisms, causes fatal diseases like-, meningitis, pneumonia as well as worsens the prognosis of cystic fibrosis patients. It is also multi-drug ...resistant and resists a wide range of antibiotics. Attempts have been made to reduce its virulence/pathogenic potential using a number of organic compounds. For this purpose, the Quorum sensing (QS) system of P. aeruginosa was targeted, which regulates its virulence. Pseudomonas Quinolone System (PQS), one of the four quorum sensing systems, producing pyocyanin pigment was chosen. 2-heptyl-3-hydroxy-4-quinolone (HHQ) is a ligand which binds to PQS protein is responsible for pyocyanin pigment production. Attempts were made to find a compound analogous to HHQ which could bind to PQS active site and inhibit the pigment formation. In-silico analysis was performed to estimate possible interactions and to find/predict the possible PQS inhibitors.
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Protozoan predation is one of the main environmental factors constraining bacterial growth in aquatic environments, and thus has led to the evolution of a number of defence mechanisms that protect ...bacteria from predation. These mechanisms may also function as virulence factors in infection of animal and human hosts. Whole transcriptome shotgun sequencing of Vibrio cholerae biofilms during predation by the amoebae, Acanthamoeba castellanii, revealed that 131 transcripts were significantly differentially regulated when compared to the non-grazed control. Differentially regulated transcripts included those involved in biosynthetic and metabolic pathways. The transcripts of genes involved in tyrosine metabolism were down-regulated in the grazed population, which indicates that the tyrosine metabolic regulon may have a role in the response of V. cholerae biofilms to A. castellanii predation. Homogentisate 1, 2-dioxygenase (HGA) is the main intermediate of the normal L-tyrosine catabolic pathway which is known to auto-oxidize, leading to the formation of the pigment, pyomelanin. Indeed, a pigmented mutant, disrupted in hmgA, was more resistant to amoebae predation than the wild type. Increased grazing resistance was correlated with increased production of pyomelanin and thus reactive oxygen species (ROS), suggesting that ROS production is a defensive mechanism used by bacterial biofilms against predation by amoebae A. castellanii.
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