NaOH Method Research Articles

Enhanced Cellulose Extraction from Banana Pseudostem Waste: A Comparative Analysis Using Chemical Methods Assisted by Conventional and Focused Ultrasound

This study investigates the effectiveness of various chemical methods, both ultrasound-assisted and non-assisted, for extracting cellulose from banana pseudostem (BPS) waste, comparing the results with commercial pine and eucalyptus cellulose fibers. Delignification treatments with NaOH (25% and 30%) and H2O2 (8%) were evaluated, applied with both conventional and focused sonication. Ultrasound-assisted methods, particularly with NaOH, achieved cellulose percentages as high as 99.5%. X-ray diffraction (XRD) analysis revealed that NaOH treatments significantly increased the cellulose crystallinity index, reaching up to 67.9%, surpassing commercial fibers. Scanning electron microscopy (SEM) results showed that NaOH treatments, especially at 30%, improved fiber morphology and exposure. Thermogravimetric analysis (TGA) indicated that methods using NaOH and focused sonication enhanced the thermal stability of the cellulose. Compared to commercial fibers, some samples obtained with the proposed methods demonstrated higher purity, yield, and thermal stability, highlighting the effectiveness of ultrasound-assisted and NaOH methods.

Exosomal miR-222-3p derived from dermal papilla cells inhibits melanogenesis in melanocytes by targeting SOX10 in rabbits.

Dermal papilla cells (DPCs) play a pivotal role in hair follicle development and can modulate melanogenesis in melanocytes (MCs) through their microenvironment. Our previous studies have demonstrated that the level of exosomal miR-222-3p derived from DPCs of white Rex rabbits are significantly higher than those of black Rex rabbits. However, the specific role and underlying molecular mechanisms of exosomal miR-222-3p in melanogenesis remain elusive. DPCs and MCs were isolated from hair follicles of Rex rabbits and identified using western blotting (WB) and immunofluorescent staining. Exosomes derived from DPCs (DPCs-exos) were characterized using nanoparticle tracking analysis, transmission electron microscopy, and WB. To investigate cell-cell crosstalk mediated by exosomes, MCs were co-cultured with CM-Dil-labeled DPCs-exos. The expression of miR-222-3p in skin tissue and exosomes was quantitatively assessed using quantitative real-time PCR (qRT-PCR). The transmission of DPCs-secreted exosomal miR-222-3p to MCs was demonstrated using Cy3-labeled miR-222-3p in conjunction with transwell assays. The impact of miR-222-3p on melanin synthesis was evaluated using the NaOH method, CCK-8, and Annexin V-FITC/PI assays. SOX10, a potential target gene regulated by miR-222-3p, was validated using a dual-luciferase reporter assay, site-specific mutation, and WB. Increased levels of miR-222-3p were observed in the skin and DPCs-exos of white Rex rabbits compared to those of black Rex rabbits. Effective internalization of CM-Dil-labeled DPCs-exos by MCs was observed. Furthermore, exosomal miR-222-3p derived from DPCs was transferred to MCs. Functionally, miR-222-3p significantly inhibited MCs proliferation, induced apoptosis and inhibited melanin synthesis. SOX10 was confirmed as a direct target of miR-222-3p in this regulatory cascade. The findings demonstrate that exosomal miR-222-3p, derived from DPCs, suppresses melanogenesis in MCs by targeting SOX10, thus unveiling a novel mechanism of exosome involvement in melanogenesis.

High-Temperature Stirring Pretreatment of Waste Rubber Particles Enhances the Interfacial Bonding and Mechanical Properties of Rubberized Concrete

This paper innovatively proposes a method of 180 °C high-temperature stirring pretreatment for waste rubber particles and compares this method with untreated, NaOH-treated, and silane coupling agent KH570-treated waste rubber particles. Fourier-transform infrared spectroscopy, X-ray diffraction analysis, water contact angle measurement, scanning electron microscopy, and energy-dispersive X-ray study are used to investigate the effects and mechanisms of different pretreatment methods on waste rubber particles. The results indicate that compared to NaOH-treated and KH570-treated waste rubber particles, the 180 °C high-temperature-stirred pretreated waste rubber particles show significantly improved cleanliness and form a hard oxide film. The study also investigates the effects of different pretreatment methods on the mechanical properties and interface binding performance of rubber concrete made from pretreated waste rubber particles. The results demonstrate that rubber concrete prepared using 180 °C high-temperature-stirred pretreated waste rubber particles substituting 20% fine aggregate exhibits the best mechanical properties and interface bonding performance. The compressive strength recovery rates after 7 and 28 days are 41.6% and 37.3%, respectively; the split tensile strength recovery rates are 47.3% and 60.6%; the axial compressive strength recovery rates are 34.1% and 18.8%; and the static compression moduli of elasticity recovery rates are 46.8% and 26.3%. High-temperature stirring pretreatment of waste rubber particles is simple to operate and suitable for scaled production. Its pretreatment effect is superior to those of the KH570 and NaOH methods, providing a reference value for the scalable application of waste rubber particles as a substitute for fine aggregate in rubber concrete.

A dilute sodium hydroxide technique for radiolarian extraction from cherts

Radiolarians have been used to determine geological ages and have contributed markedly to our understanding of Earth’s history. Hydrofluoric acid (HF) has traditionally been used to extract radiolarian fossils from siliceous deposits (i.e., radiolarian cherts), but this acid is strictly regulated because of environmental and human health concerns. Here we report on the successful extraction of radiolarians from cherts using a low-concentration NaOH solution (1 mol/L NaOH) as an alternative to HF. The degree of chert dissolution in NaOH is strongly temperature-dependent and is limited at < 80 °C. However, even a 1 mol/L NaOH solution is sufficient to dissolve chert at 100 °C. Our new NaOH method yields better-preserved radiolarian fossils compared with the conventional HF method. The 1 mol/L NaOH solution is less hazardous, easier to handle, and has fewer effects on the environment and human health than HF. Therefore, this method can be widely used for research and teaching purposes in studies of radiolarian fossils, even in institutions where HF cannot be used owing to chemical restrictions.

Selectively fractionate hemicelluloses with high molecular weight from poplar thermomechanical pulp by tetramethylammonium hydroxide

Selective fractionation of hemicelluloses is of great significance for realizing high-value application of hemicelluloses and comprehensive utilization of lignocellulosic biomass. Tetramethylammonium hydroxide (TMAH) solvent has been confirmed as a promising solvent to selectively fractionate hemicelluloses from holocellulose. Herein, TMAH solvent was adopted to pretreat poplar thermomechanical pulp (PTMP) for the selective fractionation of hemicelluloses and enhancement of enzymatic hydrolysis performance of residues. The maximal hemicelluloses yield (65.0 %) and excellent cellulose retention rate (93.3 %) were achieved after pretreatment by the 25 wt% TMAH solvent, while the delignification was only 33.9 %. The hemicelluloses fractions could be selectively fractionated with high molecular weights (109,800–118,500 g/mol), the contents of Klason lignin in them were low (3.2–5.9 %), and the dominating structure of them was 4-O-methylglucurono-β-D-xylan. Compared to the H2SO4 and NaOH methods, the hemicelluloses fractionated by TMAH method exhibited higher yields, more complete structures and higher molecular weights. Furthermore, the crystalline structure of cellulose practically remained stable, and the highest yield of enzymatic hydrolysis glucose was 57.5 %, which was 3.3 times of that of PTMP. The fractionation effectiveness of TMAH solvent was not significantly reduced after repeatedly recycling. This work demonstrated TMAH solvent could selectively fractionate hemicelluloses from PTMP and efficiently promote sustainable poplar-based biorefinery.

Kinetics of zinc oxide from sodium zincate solution by hydrolysis crystallization

The crystallization of zinc oxide from sodium zincate solution is the key step in the process for treating zinc oxide mineral ores and residues by NaOH method. The crystallization kinetics including nucleation, growth and aggregation was investigated in a batch crystallizer. It was found that zinc hydroxide could be converted into zinc oxide under hydrothermal conditions without calcinations. Effects of temperature, seed, supersaturation and agitation speed on the crystallization were studied. The main structure of zincate changed with varied temperature. Zinc oxide particles were spherical particles formed by agglomeration of zinc oxide nanorods. The growth rate, the nucleation rate and the aggregation kernel were calculated by moments analysis based on the particle size distribution. The volume growth mechanism and linear growth mechanism of zinc oxide were controlled by diffusion process and surface reaction. In batch crystallization, the nucleation rate decreased with the increase of suspension density but increased with the increase of agitation rate. The reaction time had the most significant effect on the agglomeration factor. The agglomeration between zinc oxide particles could be improved by increasing the particle collision frequency.

Comparative study of zinc oxide nanoparticles synthesized through biogenic and chemical route with reference to antibacterial, antibiofilm and anticancer activities

The present focused on comparative study on synthesis of ZnO nanoparticles (ZnO NPs) using chemical method via alkaline precipitation method (ZnO(A) NPs) using NaOH and biogenic method using termite mound extract (ZnO(B) NPs). GC-MS analysis revealed that D-limonene present in termite mound extract might be responsible for the synthesis of ZnO(B) NPs. XRD patterns confirmed hexagonal crystalline structure of ZnO(A) and (B) NPs. Results of antibacterial activity illustrated that ZnO(B) NPs showed its potential against Pseudomonas aeruginosa, ESBL-1, ESBL-2 and EBSL-3. Antibiofilm studies revealed that ZnO(B) NPs exhibited optimum decline in MRSA biofilm formation than ZnO(A) NPs. In addition, ZnO(B) NPs showed potent cytotoxic effect against lung cancer cell lines A549 with IC50 of 35.16 ± 0.10 μg/mL in comparison with ZnO(A) NPs (IC50- 55.09 ± 0.30 μg/mL). Overall, the results revealed that biogenic synthesis of ZnO NPs ensures its biosafety level and enhanced biological activity when compared to chemical synthesis method.

Ni, Co and Ni-Co-Modified Tungsten Carbides Obtained by an Electric Arc Method as Dry Reforming Catalysts

Dry reforming of methane (DRM), to produce synthesis gas, is one of the most important chemical reactions used for the industrial production of hydrogen and leads to the synthesis of hydrocarbons (liquid fuels) and other valuable products. A cost-effective alternative to active and stable noble metal DRM catalysts, with comparable catalytic performance, can be composite materials based on nickel, cobalt and transition metal carbides. In this line, the present work proposes a non-standard way to obtain dry reforming catalysts of Ni, Co and Ni-Co-modified tungsten carbide (WC) produced by an electric arc method. Different amounts of nickel, cobalt and their mixtures were deposited on tungsten carbide by deposition-precipitation with NaOH (DP) and incipient wetness impregnation (IWI) methods. The resulting materials were characterized by N2 adsorption-desorption, transmission electron microscopy, energy dispersive spectroscopy, X-ray diffraction and X-ray photoelectron spectroscopy, and their performance was evaluated in DRM. The composition and preparation method of catalysts predetermined their structural, textural and electronic properties, playing a decisive role in their activity for DRM. DP-prepared 20%Ni/WC material remained resistant to oxidation, both that of the active metal (nickel) and of the tungsten carbide, as well as to coking during DRM. This sample proved to be the most active and stable among all studied materials. Possibly, the resistance to oxidation and coking was due to a more efficient implementation of the oxidation/(re)carbonization cycle on the surface of this catalyst.

An ecofriendly agar extraction strategy using KOH for boiling extraction and MgCl2 for alkali neutralization

In this study, a new strategy for extracting agar from Gracilaria was proposed to replace the traditional NaOH extraction, using low concentration of KOH solution and MgCl2 neutralization (KOH–MgCl2 method) under homogeneous conditions. The KOH–MgCl2 method was more convenient than the traditional NaOH method, with 84% less alkali consumption, 76.4% less water consumption, and 80% less wastewater. The physicochemical properties of the agar extracted by the KOH–MgCl2 method (KMA) at different alkali concentrations were compared with those of the agar extracted with the traditional NaOH extraction method (NA) under scale-up tests. The results showed that KMA3 had lower sulfate content and higher 3,6-anhydro-α-l-galactose content and molecular weight than NA, indicating that the KOH–MgCl2 method had better desulfurization and lower degradation effect. Thus, this new method has potential to replace the traditional NaOH extraction method.

Recovery of polyhydroxyalkanoates (PHAs) polymers from a mixed microbial culture through combined ultrasonic disruption and alkaline digestion

PHAs are a form of cellular storage polymers with diverse structural and material properties, and their biodegradable and renewable nature makes them a potential green alternative to fossil fuel-based plastics. PHAs are obtained through extraction via various mechanical, physical and chemical processes after their intracellular synthesis. Most studies have until now focused on pure cultures, while information on mixed microbial cultures (MMC) remains limited. In this study, ultrasonic (US) disruption and alkaline digestion by NaOH were applied individually and in combination to obtain PHAs products from an acclimated MMC using phenol as the carbon source. Various parameters were tested, including ultrasonic sound energy density, NaOH concentration, treatment time and temperature, and biomass density. US alone caused limited cell lysis and resulted in high energy consumption and low efficiency. NaOH of 0.05–0.2 M was more efficient in cell disruption, but led to PHAs degradation under elevated temperature and prolonged treatment. Combining US and NaOH significantly improved the overall process efficiency, which could reduce energy consumption by 2/3rds with only minimal PHAs degradation. The most significant factor was identified to be NaOH dosage and treatment time, with US sound energy density playing a minor role. Under the semi-optimized condition (0.2 M NaOH, 1300 W L-1, 10 min), over 70% recovery and 80% purity were achieved from a 3 g L−1 MMC slurry of approximately 50% PHAs fraction. The material and thermal properties of the products were analyzed, and the polymers obtained from US + NaOH treatments showed comparable or higher molecular weight to previously reported results. The products also exhibited good thermal stability and rheological properties, compared to the commercial standard. In conclusion, the combined US and NaOH method has the potential in real application as an efficient process to obtain high quality PHAs from MMC, and cost-effectiveness can be further optimized.

CDK1 promotes the proliferation of melanocytes in Rex rabbits.

The fur color constitutes one of the most important economic characteristics of fur animals and is determined by the content of melanin. A previous study has shown that the cyclin-dependent kinase 1 (CDK1) is a member of the protein kinase family, involved in forming the color of the fur in Rex rabbits. However, its effect on the melanocytes remains unclear. This study aimed to provide evidence for the role of CDK1 in melanogenesis. This study measured the expression of CDK1 in Rex rabbit skins of six coat colors using qRT-PCR. The CDK1-mediated regulation of the pigmentation-related genes and cyclin-dependent kinases were analyzed. The melanin content, proliferation, and apoptosis of the melanocytes were analyzed using the NaOH, CCK8, and Annexin V-FITC methods. The CDK1 expression in the skin of the rex rabbits with different coat colors was found to be regular, and the expression level was found to be the highest in the skin of the black rex rabbits (P < 0.05). The overexpression/knockdown of CDK1 was found to significantly increase/decrease the melanin content in the melanocytes (P < 0.01). Besides, CDK1 was found to significantly promote the proliferation of the melanocyte and inhibit apoptosis (P < 0.01). Furthermore, the overexpression of CDK1 was found to significantly affect the expression of the other melanin-related genes like TYR, PMEL, DCT, as well as the mRNA expression of the cyclin-dependent kinases CDK4, CDK6, CDK8, CCNB1. The results indicated that CDK1 can serve as a key gene regulating melanogenesis, melanocyte proliferation, and apoptosis, providing a new theoretical basis for studying the mechanism by which the different colors of the fur evolve in mammals.

Tuberculosis caused by Mycobacterium orygis in wild ungulates in Chennai, South India.

We report the isolation of Mycobacterium orygis, a member of Mycobacterium tuberculosis complex (MTBC), from two black bucks (Antelope cervicapra) and one spotted deer (Axis axis) from the Guindy National Park forest range in Chennai, India. Lung tissue and lymph node samples collected during post-mortem examination were processed using NaOH method and cultured in solid and liquid media. DNA extracted from the cultured isolates was used to amplify the mpt64 gene by specific primers and the band visualized at 240bps confirmed the isolates as a member of MTBC. Further examination of these isolates by spoligotyping and whole-genome sequencing confirmed the isolates as M. orygis and the phylogenetic tree revealed their well-clustered position with other M. orygis isolates around the globe. The deletion of RD7-RD10, RDOryx_1, RDOryx_4, RD12Oryx, RD301 and RD315 further substantiated these isolates as M. orygis. The exact source of infection in animals was untraceable and the pairwise comparison of the genomes based on single-nucleotide polymorphisms difference did not detect any events of transmission within the affected animals. Nevertheless, it would be wise to take into account the environment where there exists a high chance of transmission due to the increased human-animal interaction. Since it is well known that the pathogen is capable of causing infection in both human and animal hosts, systematic surveillance and screening of spotted deer, black buck as well as humans in the vicinity is essential for successful implementation of the One Health approach.

Valorization of alkaline hydroxide modified coal fly ash to efficient adsorbents for enhanced carbon capture

High carbon content coal fly ash was used in this study to synthesize an adsorbent using two step fusion hydrothermal method. Both KOH and NaOH were used in the fusion to observe deviations from the usual NaOH method. They were compared in terms of their physico-chemical attributes. The SEM micrographs showed that coal fly ash lost its geoid structures after fusion with the alkalis. XRD diffractograms showed that both K/Na/CFA-Heavy adsorbent and K/Na/CFA-Light adsorbent were highly amorphous. The K/Na/CFA-Light adsorbent had inferior morphology but better BET than K/Na/CFA-Heavy adsorbent. Even in terms of CO2 uptake capacity, at room temperature K/Na/CFA-Light adsorbent (1.48 mmol/g) outperformed K/Na/CFA-Heavy adsorbent (1.13 mmol/g). A maximum value CO2 uptake value of 1.48 mmol/g was observed for K/Na/CFA-Light adsorbent at 298 K. Kinetic studies displayed that the adsorption process was best explained by the Avrami model with an R2 value of 0.99. Cyclic stability studies were performed at 298 K and they showed that that K/Na/CFA-Light adsorbent showed a cyclic retention capacity of 80% at the end of five cycles.

Baricitinib is Effective in Treating Progressing Vitiligo in vivo and in vitro.

ObjectiveTo evaluate the clinical efficacy and safety of baricitinib, a Janus kinase (JAK) inhibitor, in treating patient with progressing vitiligo, and to further explore the regulation of baricitinib on melanocytes (MCs) in vitro.MethodsFour patients with progressing vitiligo were treated with oral baricitinib for a total of 12 weeks. MCs were cultured in vitro and irradiated by high-dose ultraviolet B (UVB, 150mJ/cm2) to make an MC damaged model (MC-Ds). Baricitinib was added at a final concentration of 25 μM. Dopamine staining and NaOH method were used to measure the tyrosinase activity and melanin level, respectively, real-time quantitative polymerase chain reaction (RT-qPCR) was used to measure the mRNA levels of tyrosinase (TYR), tyrosinase-related protein-1 (TRP-1).ResultsSignificant re-pigmentation was observed in the week 12 without obvious side effects. Depigmentation occurred in 2 patients at the 3-month follow-up. Laboratory research found that higher doses of UVB irradiation (150mJ/cm2) could decrease melanin content of MCs, baricitinib (25 μM) could significantly promote tyrosinase activity, melanin content, and TYR, TRP-1 gene expression of MC-Ds.ConclusionOur preliminary study showed that baricitinib was effective and safe in treating progressing vitiligo. Baricitinib could promote tyrosinase activity, melanin content and TYR, TRP1 gene expression of MC-Ds in vitro.

Preparation, structure characterization of carboxymethylated schisandra polysaccharides and their intervention in immunotoxicity to polychlorinated biphenyls

Carboxymethylation is a well-known modification process for polysaccharides. To evaluated structural features and biological availability of carboxymethyl, carboxymethylated schisandra polysaccharides (CSP) was synthesized using an optimized chloroacetic acid /NaOH method. Optimal modification parameters were reaction temperature of 62.67 ℃, reaction time of 4.27 h, and 0.83 g chloroacetic acid. The main fraction of CSP (CSPP) was obtained by purification using DEAE-52 column. Chemical analysis indicated that CSPP contained carboxymethyl groups with a Mw of 1.698 × 104 g/mol and degree of substitution of 0.88 and composed of mannose, glucose and galactose at ratio of 1: 44.8: 3.7. Moreover, CSPP have improved water solubility (12.56 ± 0.04 mg/mL) and existed as a slight extended flexible chain. CSPP exhibited higher immunomodulating activities to polychlorinated biphenyl-126 (PCB126) -exposure mice than unmodified polysaccharide, as shown by improving PCB 126-induced reduction of body weight gain and atrophy of the immune organ, diminishing PCB126-induced inhibition of cytokines production and reversing damage of spleen caused by oxidative stress in PCB126-treated mice. It could be concluded that introduction of carboxymethyl groups to polysaccharide can alter its physicochemical characteristic to enhance its immunoregulatory activity. This study suggested that CSPP potentially serve as an effective nutritional intervention agent to reverse the PCB126-induced immunosuppression.

Effect of Ultraviolet B Irradiation on Melanin Content Accompanied by the Activation of p62/GATA4-Mediated Premature Senescence in HaCaT Cells.

ObjectiveTo explore the effect and mechanism of ultraviolet B (UVB) on melanin synthesis and premature senescence in human immortalized keratinocytes (HaCaT) cells.MethodsHaCaT cells were irradiated with 0, 20, 50, 80, 100, 150, and 200 mJ/cm2 of UVB. NaOH method was used for melanin content assay, cellular tyrosinase (TYR) activity was determined by 3,4-Dihydroxy-L-phenylalanine (L-DOPA) oxidation to dopachrome, premature senescence was analyzed by senescence-associated beta-galactosidase (SA-β-gal) staining kit, and the levels of p21, p16, p62, and GATA4 proteins were detected by Western blotting. Premature senescence was inhibited by the inhibitors of ataxia telangiectasia mutated (ATM) or ataxia telangiectasia and Rad3–related (ATR), and the p53 signaling pathway was activated by Nutlin-3. The mRNA levels of senescence-associated secretory phenotype (SASP) factors including tumor necrosis factor alpha (TNF-α), vascular endothelial growth factor A (VEGF-A), and interleukin-8 (IL-8) were measured by real-time quantitative polymerase chain reaction in HaCaT cells after 80 mJ/cm2 of UVB irradiation.ResultsThe melanin level increased significantly with the elevation of irradiation dose (F = 28.19, 43.82, 143.60, P < .05), reaching the peak at the dose of 80 mJ/cm2. The tyrosinase activity increased significantly (F = 84.50, P < .05), the percentage of premature senescence increased (F = 16.31, P < .05), the levels of p62 decreased, and the level of GATA4 increased obviously with the increase of UVB dose after irradiation. The UVB-induced promotion of GATA4 level was significantly inhibited by being treated with ATM or ATR inhibitor. However, this did not occur in the Nutlin-3-treated group. The mRNA and protein expression of TNF-α increased significantly at 72 h at 80 mJ/cm2 of UVB irradiation.ConclusionsMelanin contents increased first and decreased afterward with the increasing of UVB irradiation. The decrease of p62-mediated selective autophagy was accompanied by the accumulation of GATA4 after different doses of UVB irradiation. Activation of this p62/GATA4 pathway depends on the ATM and ATR but is independent of p53, and the SASP factor was activated in HaCaT cells at 80 mJ/cm2 of UVB irradiation.

Examination of Extracellular Polymer (EPS) Extraction Methods for Anaerobic Membrane Bioreactor (AnMBR) Biomass

Membrane bioreactor fouling is a complex process, which is typically driven by extracellular polymeric substances (EPS), a complex mixture of polysaccharides, proteins, lipids, humic substances, and other intercellular polymers. While much is known about fouling in aerobic membrane reactors, far less is known about fouling in anaerobic membrane bioreactors (AnMBR). Much of this knowledge, including EPS extraction methods, has been extrapolated from aerobic processes and is commonly assumed to be comparable. Therefore, several extraction methods commonly used for aerobic EPS quantification, including ultrasonication, ethylenediaminetetraacetic acid (EDTA), and formaldehyde plus sodium hydroxide (CH2O+NaOH), were evaluated to determine the most suitable extraction method for EPS of anaerobic microorganisms in an AnMBR. To maximize EPS yields, each extraction was performed four times. Experimental results showed that the EDTA method was best for EPS quantification, based on chemical oxygen demand (COD), dissolved organic carbon (DOC), and protein yields: 1.43 mg COD/mg volatile suspended solids (VSS), 0.14 mg DOC/mg VSS, and 0.11 mg proteins/mg VSS. In comparison, the CH2O+NaOH method maximized the extraction of carbohydrates (0.12 mg carbohydrates/mg VSS). However, multiple extraction cycles with EDTA and ultrasonication exhibited lower extracellular adenosine triphosphate (ATP) concentrations compared to CH2O+NaOH extractions, indicating lower levels of released intracellular substances. Successive EPS extractions over four cycles are better able to quantify EPS from anaerobic microorganisms, since a single extraction may not accurately reflect the true levels of EPS contents in AnMBRs, and possibly in other anaerobic processes.

Methylcobalamin Protects Melanocytes from H2O2-Induced Oxidative Stress by Activating the Nrf2/HO-1 Pathway.

PurposeOxidative stress is considered a major determinant in the pathogenesis of vitiligo. Methylcobalamin (MeCbl) is an activated form of vitamin B12 that regulates inflammatory factors, counters oxidative stress, and reduces apoptosis in many disease models. However, the specific mechanism of MeCbl repigmentation against vitiligo is unknown. In this study, we explored the effect of MeCbl on melanocytes following hydrogen peroxide (H2O2)-induced oxidative stress.MethodsWe established an oxidative stress model using the immortalized human normal melanocyte cell line PIG1. We used a Cell Counting Kit-8 (CCK-8) to detect drug cytotoxicity, and we measured the melanin content of cells using the NaOH method. Intracellular oxidative damage was assessed by flow cytometry and antioxidant enzyme detection kits. In addition, we assessed the presence of apoptosis by flow cytometry and Western blots. We explored the underlying mechanisms of MeCbl during oxidative stress in melanocytes by analyzing the results of experiments based on real-time quantitative polymerase chain reaction (RT-qPCR), Western blotting, and laser scanning confocal immunofluorescence microscopy. Finally, we repeated the experiments after applying an inhibitor to block the Nrf2 pathway.ResultsWe found that MeCbl treatment enhanced cell viability, increased melanin content, reduced intracellular reactive oxygen species (ROS) accumulation, increased the activities of antioxidant enzyme superoxide dismutase (SOD) and catalase (CAT), reduced melanocyte apoptosis, and up-regulated the expression of the Nrf2/HO-1 pathway. Moreover, the protective effects of MeCbl were significantly weakened after inhibiting the Nrf2/HO-1 pathway.ConclusionOur results indicate that MeCbl attenuated the H2O2-induced oxidative stress in melanocytes by activating the Nrf2/HO-1 pathway, this suggests that MeCbl may be an effective treatment against vitiligo.

Development of microwave-assisted alkaline pretreatment methods for enhanced sugar recovery from bamboo and corn cobs: Process optimization, chemical recyclability and kinetics of bioethanol production

The present study optimized two microwave-assisted alkaline (Na3PO4.12H2O and NaOH) pretreatment methods for the enhancement of sugar recovery from different lignocellulosic substrates (bamboo and corn cobs) with varying structural compositions. Subsequently, the chemical recyclability of the optimized alkaline pretreatments were evaluated on corn cobs. Furthermore, kinetics of microbial cell growth and bioethanol production in simultaneous saccharification and fermentation (SSF) processes were assessed. The optimized Na3PO4.12H2O pretreatment conditions resulted in the maximum reducing sugar yield (0.512 g/g) from corn cobs. Interestingly, the recyclability studies demonstrated that the NaOH-based black liquor resulted in a slightly higher average sugar yield (0.37 g/g) compared to the Na3PO4.12H2O (0.31 g/g) over three pretreatment cycles. Kinetics showed a maximum specific growth rate and maximum potential bioethanol concentration of 0.175 h−1 and 16.928 g/L respectively for the optimized NaOH pretreated corn cobs. The findings from this study provide significant knowledge enhancements pertaining to the use of gold standard, well-known NaOH methods, in addition to the emerging Na3PO4.12H2O alkaline catalyst for the pretreatment of lignocellulosic substrates with varying structural compositions. Moreover, recyclability of Na3PO4.12H2O and NaOH black liquor demonstrated the potential to reduce costs associated with the application of chemicals and fresh water in pretreatment systems. Kinetics of cell growth and bioethanol production elucidates noteworthy indices such as the maximum specific growth rate of the cells, lag time and maximum bioethanol production for lignocellulosic process development and scale-up procedures.

Mechanical seed processing improves the seed quality and reduces Karnal Bunt incidence in seed lots of varied wheat cultivars

Quality seed production differs from commercial or grain crop production in several aspects. Special methods, precautions and operations are needed to deploy to produce seed of optimum quality. Seed processing influences the quality as well as marketability of seed and could be effectively deployed for elimination of diseased and damaged seeds from healthy seeds. Karnal Bunt (KB) of wheat is an internationally regulated disease and adversely affects the yield, seed appearance and trade. Therefore, effective seed testing and processing is vital to check the spread of disease through the seed. In the present study, efficacy of mechanical seed processing with recommended screen sizes were tested in six different wheat varieties and found that DBW-222 and DBW-187 shown highest recovery percentage of 90 and 89% respectively. HD-2967 and HD-3086 recorded seed recovery of 87 and 86% respectively. Lowest recovery was observed in case of durum wheat variety i.e. DDW-47 (85%). Further, eleven seed lots were tested for eight seed quality parameters and it was found that all carry over and fresh seed lot maintained germination above Indian Minimum Seed Certification Standards i.e. 85%. Further, processed seed lot showed lower KB infection as compared to un-processed seed lots, being minimum in processed seed lot of DBW-187 (0.15%) produced at Meerut. However, seed lot of DBW-187 and DBW-222 produced at Karnal recorded 0.17% KB incidence, followed by HD-3086 and HD-2967 (0.18%) both produced at Meerut. Further, DDW-47 recorded 0.23% of KB incidence which was higher among all the varieties after processing. Among two methods adopted for KB detection, NaOH method was found to be more sensitive (processed as well as un-processed seed lots) as compared to dry inspection method.