SP2 Groups Research Articles

Assessment of Bacillus species capacity to protect Nile tilapia from A. hydrophila infection and improve growth performance.

The present study evaluated the capacity of three Bacillus species to improve health status and growth performance of Nile Tilapia fed with high levels of soybean meal and challenged with Aeromonas hydrophila. In vitro experiments showed that β-hemolysin and metalloprotease enzymes were produced by A. hydrophila throughout the exponential growth phase. In vivo experiments showed that 107 colony-forming units (CFUs)/ml of this pathogen killed 50% of control group fishes in 13 days. To evaluate the influence of Bacillus strains on health status and growth performance in Nile Tilapia, 180 fishes (33.44 + 0.05 g) were distributed in 12 tanks of 200 L each, and animals were fed twice per day until satiety. 1) Control group without Bacillus, 2)Bacillus sp1, 3) Bacillus sp2, and 4) Bacillus sp3 groups were formulatedcontaining 106 CFU/g. After 40 days of feeding, the fishes were intraperitoneally injected with 1 ml of A. hydrophila at 2 × 107 CFU/ml, and mortality was recorded. The results showed that cumulative mortality rate was significantly (p< 0.05) lower in the Bacillus sp1 (25%), sp2 (5%), and sp3 (15%) groups, than the control group (50%). Weight gain was also significantly better (p< 0.05) in the Bacillus sp1 (36%), sp2 (67%), and sp3 (55%) groups with respect to the control group (30%). In conclusion, functional diet formulated with high levels of soybean meal and supplemented with Bacillus sp2 could be an alternative to protect Nile tilapia cultures from A. hydrophila infections and improve fish growth performance.

Spirulina (Arthrospira platensis) supplementation: Impact on growth, metabolism, and antioxidant status in zebrafish

AbstractZebrafish (Danio rerio) is a valuable model for biomedical research because of its mammalian genetic similarities, rapid reproduction, and low maintenance costs. However, further investigation is required regarding their nutritional requirements and standardized laboratory diets. This study evaluated the metabolic and growth responses of zebrafish juveniles fed on diets supplemented with spirulina, Arthrospira platensis (SP) at different levels for 77 days. Six diets with SP inclusion levels of 0%, 2%, 4%, 6%, 8%, and 10% (SP0‐SP10) were formulated. A total of 300 zebrafish juveniles with an average initial weight of 0.113 ± 0.10 g (mean ± SD) were randomly distributed across six groups, with five replicates per group, each containing 10 animals. After 77 days, the SP6 group demonstrated significantly enhanced growth performance compared with the other supplementation levels. The condition factor was markedly higher in the SP6 and SP8 groups than in the SP0 group. No significant effects on total cholesterol levels were observed, but the SP4, SP6, and SP10 diets decreased triglyceride levels. Lipase activity was higher in the SP6 and SP8 groups than in the control group, whereas amylase activity showed no significant differences between treatments. Catalase and superoxide dismutase activities were significantly higher in the SP8 and SP10 groups than in the SP0 and SP2 groups. Glutathione S‐transferase activity was higher in the SP6, SP8, and SP10 groups than in the SP0 group. In addition, SP inclusion in zebrafish diets improved female gonadal development. In conclusion, this study indicates that SP supplementation has substantial potential as a growth promoter, positively influencing lipid metabolism and antioxidant enzyme activity without affecting zebrafish survival.

Effects of partial replacement of fishmeal with Spirulina platensis powder and addition of Spirulina platensis polysaccharide on growth, nutrition, antioxidant capacity and gut microbiota of Micropterus salmoides

Fish is currently considered a primary protein in the human diet, and the high demand for fish will stimulate the growth of aquaculture. However, a lack of high-quality fish feed (fishmeal) has led to a decline in the quality and yield of aquatic products. Therefore, an alternative high-quality protein source for fish meal is required to sustain the industry. This study assessed the effects of incorporating Spirulina platensis (SP) dried powder as a partial replacement for fishmeal and supplementing with S. platensis purified polysaccharides (PSP) on the growth, nutritional value, and health status of the largemouth bass, Micropterus salmoides, to address the challenges of fishmeal scarcity and promote sustainable development in fish aquaculture. Juveniles were fed four isonitrogenous and isolipidic diets containing SP at 0% (SP0), 3% (SP3) and 6% (SP6) and PSP at 0.3% for 56 days. The results showed that both the SP3 and SP6 groups displayed significantly (P < 0.05) improved growth performance and lower hepatosomatic indices than the control diet (SP0). Whole-body crude protein and protein efficiency significantly increased in both the SP3 and SP6 groups compared with SP0 (P < 0.05). Conversely, crude lipid content notably (P < 0.05) decreased in SP3 (5.96%) and SP6 (5.41%) in contrast to SP0 (6.59%). The muscle amino acid composition of the PSP, SP3, and SP6 groups also improved significantly (P < 0.05) compared to that of the SP0. Liver SOD activity was significantly increased from 1.11 U/mg in SP0 to 1.22–1.24 U/mg in SP3 and SP6 (P < 0.05), while MDA levels declined accordingly. Serum triglyceride levels were significantly lower in SP3 than in SP0 (P < 0.05) but remained stable in the SP6 and PSP groups. Low-density lipoprotein cholesterol decreased significantly in the SP3 and SP6 groups, but no significant effect was observed in the PSP group. Alanine aminotransferase activity was significantly (P < 0.05) lower in the PSP, SP3, and SP6 groups than in SP0. Aspartate aminotransferase activity in PSP and SP3 was significantly lower than in SP0 (P < 0.05), but showed no significant difference with SP6 (P > 0.05). Intestinal trypsin and amylase activities significantly improved in the PSP, SP3, and SP6 groups (P < 0.05), and lipase activities in PSP and SP3 increased significantly compared to those in SP0 (P < 0.05). The intestinal microbiome displayed significantly higher Shannon index scores for SP3 (0.83) and SP6 (0.93) than for SP0 (0.61). The relative abundances of the phylum Fusobacteria and genus Cetobacterium were significantly increased, whereas Proteobacteria and Plesiomonas were significantly decreased in the PSP and SP3 groups compared with that in SP0 (P < 0.05). The present study indicated that the replacement of fishmeal with 3–6% SP and 0.3% PSP addition could improve the growth performance, protein efficiency, muscle nutritional value, liver health, antioxidant capacity, intestinal digestive enzyme activity, and intestinal microbiota diversity of the largemouth bass. Therefore, the partial replacement of SP or the addition of PSP has great potential in promoting healthy aquaculture of largemouth bass.

The Effects of Manual Acupuncture on Mitochondrial Fusion and Fission Gene Expression in Rat Spleen

A significant amount of research has been conducted to establish the validity of acupuncture, and it has been demonstrated through animal disease model studies that acupuncture influences mitochondrial changes. However, to more accurately examine the mechanisms of acupuncture treatment effectiveness in pathological models, it is crucial to investigate changes in disease-free animals. Among various hypotheses regarding the effects of acupuncture on the body, we focused on the result that acupuncture stimulation is related to mitochondria. We examined the effects of acupuncture mitochondrial fission and fusionrelated mediators in disease-free Sprague Dawley (SD) rats' spleen meridian acupoints. SD rats were divided into control, SP1, SP2, SP3, SP5, and SP9 acupuncture groups. Acupuncture was performed at each point for 10 minutes daily for four days. Peroxisome proliferator-activated receptor-gamma coactivator 1-α (PGC-1α) and fission protein 1 (Fis1) levels were evaluated using quantitative real-time polymerase chain reaction (qRT-PCR), while dynamin-related protein 1 (DRP1), optic atrophy-1 (OPA1), mitofusin-1 (MFN1), and mitofusin-2 (MFN2) levels were assessed via western blotting. Mitochondria protein concentrations and NADH dehydrogenase activity in spleen tissues were measured using enzyme-linked immunosorbent assay (ELISA). PGC-1α expression decreased in the SP1 (p < 0.01), SP5 (p < 0.05), and SP9 (p < 0.05) groups, while Fis1 expression increased in the SP1 (p < 0.01), SP5 (p < 0.01), and SP9 (p < 0.05) groups. DRP1, OPA1, MFN1, and MFN2 levels exhibited no significant changes. Mitochondrial protein concentrations decreased in the SP2 (p < 0.01), SP3 (p < 0.01), SP5 (p < 0.01), and SP9 (p < 0.01) groups, while NADH dehydrogenase activity decreased in the SP2 (p < 0.05) and SP9 (p < 0.05) groups. Acupuncture at the SP9 acupoint influenced the mitochondrial fission pathway by modulating PGC-1α and Fis1 mediators in the rat spleen under non-disease conditions.

Influence of spirulina supplementation on growth performance, puberty traits, blood metabolites, testosterone concentrations, and semen quality in Barki male lambs.

The fertility and genetic value of the flock can be enhanced by selecting lambs with highly developed early puberty characteristics. Spirulina (SP) has been evaluated as a natural product supplement to boost lamb growth, immunity, and productivity. Study growth performance, blood metabolites, puberty development traits, semen quality, and seminal plasma biochemical concentrations of growing Barki lambs when supplemented with SP at different levels. in a 24 weeks study, 30 Barki male lambs weighing an average of 21.78 ± 2.56 kg, with a body condition score of 3.20 ± 0.55 and an age of about 16 ± 0.24 weeks were used. The lambs were randomly assigned to three groups (10 lambs each) of daily SP supplementation levels per lamb of 0 ml (control), 50 ml (SP1), and 100 ml (SP2). The SP powder was made into a water suspension using SP to water ratio of 1 g:10 ml. The growth characteristics, as well as the development of puberty, blood metabolites, and semen quality analysis of every lamb, were measured. The growth performance was greater (p < 0.05) in SP2 lambs compared with other lambs. While daily dry matter intake was not affected by SP treatment, feed efficiency had significantly improved in SP2 groups. Furthermore, the SP2 lambs have attained puberty at early ages than the control lambs. The testes volume of SP2 lambs was bigger (p < 0.05) than other groups throughout the pre-pubertal up to the puberty stage. The addition of SP had no effects on the total protein, glucose, and triglycerides concentrations. Meanwhile, the cholesterol concentration was lowest (p < 0.05) in the SP2 lambs. The blood and seminal plasma levels of alanine aminotransferase and aspartate aminotransferase decreased (p < 0.05) in the SP lambs more than their control counterparts. The levels of superoxide dismutase reduced glutathione, and total antioxidants had increased (p < 0.05) in the treated lambs compared with the control group. Further, the malondialdehyde levels decreased (p < 0.05) in the SP-treated lambs. Additionally, the SP2 lambs produced better semen quality than the control lambs. SP supplementation (100 ml/head/day) enhanced growth performance, feed efficiency, and antioxidative status, exerting a positive influence on the physiological parameters and sexual behavioral patterns at puberty in Barki lambs.

Sustainable synthesis of nitrogen-doped fluorescent carbon quantum dots derived from Cissus quadrangularis for biomarker applications

This study demonstrated an environmentally friendly, cost-effective, and easy method for manufacturing biocompatible fluorescent carbon quantum dots (CQDs) from the leaf extract of the medicinal herb Cissus quadrangularis. As-synthesized nitrogen doped-CQDs had fluorescence quantum yields of up to 5%. The presence of pyrrolic/pyridinic-N, quaternary-N (N–C3), and OC–N, as verified by X-ray photoelectron spectroscopy, reveals that nitrogen atoms were efficiently doped in CQDs. The size distribution of as-synthesized CQDs was found to be within 4–9 nm using a high-resolution transmission electron microscope. Meanwhile, nuclear magnetic resonance studies showed the presence of a significant proportion of sp2 and sp3 carbon groups. The zeta potential of as-synthesized CQDs was −7.8 mV, demonstrating the presence of a negatively charged surface with good stability in aqueous solution. Furthermore, the development of easy, affordable, and non-destructive fluorescence-based staining agents as an alternative to organic or synthetic dyes is widely sought. In this regard, as-synthesized N-doped CQDs shown remarkable fluorescent staining capabilities in this study and might be employed as a useful probe for optical and bio-imaging of bacteria, fungal, and plant cells. On the other hand, the cytotoxicity and cell viability of pine leaf, mushrooms, algae, fungus, and bacteria have also been examined. Even at higher doses (10.9 mg/ml), cell survival was demonstrated to be rather excellent and cytotoxicity was minimal for up to 4 days.

Growth performance, antioxidant activities, and immunological responses of hapa-reared thinlip mullet (Liza ramada) juveniles fed on diets supplemented with spirulina (Arthrospiraplatensis)

Spirulina (Arthrospira platensis) (SP) has been utilized for a long time as a valued feed supplement because of its proteinous content and other beneficial phytochemical compounds. Herein, we investigated the influences of SP-supplemented diets on growth, body somatic indices, digestive enzymes, hepatic antioxidant activities, and immunological responses of hapa-reared thinlip mullet (Liza ramada) juveniles. Fish were assigned in six triplicate groups and were fed for consecutive 60 days on the prepared experimental diets containing varying SP levels as 0.0, 2.0, 4.0, 6.0, 8.0, and 10.0 g/kg diet and defined as control (CNT or SP0), SP2, SP4, SP6, SP8, and SP10 groups, respectively. The results indicated that dietary SP supplementation linearly and quadratically improved the fish growth performance, and the highest growth indices were found in the SP8 group. However, dietary SP supplementation did not significantly alter feed conversion ratio (FCR), survival rate (%), hepato-somatic index, and viscera-somatic index among all experimental groups. Meanwhile, digestive enzymes (lipase, α-amylase, and proteases) in the mid-intestine were also linearly and quadratically increased in all SP-fed groups, and their uppermost values were noted in the SP8 group. Hepatic antioxidants such as superoxide dismutase, catalase, and total antioxidant capacity in SP-supplemented groups were significantly elevated than the CNT group. Conversely, hepatic malondialdehyde contents were decreased significantly along with increasing dietary SP-supplementation levels. The immunological parameters such as lysozyme, respiratory burst, and alternative complement activities were significantly elevated in SP-fed groups than in the CNT group. These findings evoked that feeding SP-supplemented diets (especially at 8.0 g/kg diet) significantly promoted the growth, digestive enzymes, hepatic antioxidant status, and immunity of L. ramada juveniles.

Green, sustainable, and economical synthesis of fluorescent nitrogen-doped carbon quantum dots for applications in optical displays and light-emitting diodes

Fluorescent carbon quantum dots (CQDs) have attracted increasing attention in recent years because of their multiple benefits, including low toxicity, biocompatibility, simplicity of functionalization, eco-friendly production, and a wide range of applications. However, expensive precursors and manufacture, as well as a time-consuming procedure, limit their economical design, which must be addressed. We provide a straightforward, cost-effective, eco-friendly, and long-term synthesis method for fluorescent CQDs based on an affordable medicinal plant precursor such as Cissus quadrangularis. The nitrogen-doped CQDs produced had a homogenous size distribution (4–9 nm) and green fluorescent nature, as well as strong photo-stability, excellent water solubility, and a quantum yield of roughly 5%. The existence of a large fraction of sp2 and sp3-carbon groups, as well as other hydrophilic oxygen and nitrogen-containing groups, was confirmed. Potential fluorescence processes are also hypothesized. Furthermore, we report a successful demonstration of N-CQDs for possible and cost-effective applications in quantum dot-based optical displays and down-conversion green emissive light-emitting diodes.

Microwave-Assisted Green Synthesis of Carbon Quantum Dots Derived from Calotropis Gigantea as a Fluorescent Probe for Bioimaging.

An eco-friendly, cost-effective, and convenient approach for synthesizing biocompatible fluorescent carbon quantum dots (CQDs) from the leaf extract of the medicinal plant Calotropis gigantea, commonly known as crown flower, has been demonstrated in this work. Fluorescence quantum yields of up to 4.24 percent were observed in as-synthesized CQDs. The size distribution of the as-synthesized CQDs varied from 2.7 to 10.4nm, with a significant proportion of sp2 and sp3 carbon groups verified by nuclear magnetic resonance analysis. The zeta potential of as-synthesized CQDs was measured to be -13.8mV, indicating the existence of a negatively charged surface with incipient instability in aqueous suspension. Furthermore, as an alternative to organic or synthetic dyes, the development of simple, inexpensive, and non-destructive fluorescence-based staining agents are highly desired. In this regard, as-synthesized CQDs have shown remarkable fluorescent staining capabilities in this work and might be utilised as a suitable probe for optical and bio-imaging of bacteria, fungi, and plant cells.

Antioxidant and Cytotoxicity Activities of the Fermentation Extract of the Endophytic Fungi from the Marine Biota of Colt Coral

Indonesia has the largest and most biodiverse coral reef in the world. Colt coral has not been studied and explored especially endophytic fungi associated with the coral. Endophytic fungi are highly potential for the production of antioxidant and anticancer compounds. This research aimed to study the antioxidant and cytotoxic activities of fermentation extract from endophytic fungi from colt coral. Filtrate and mycelium extracts were obtained from static and shake fermentations of isolate SKF 15. Antioxidant and cytotoxic assays were conducted by free radical scavenger 1,1-diphenyl-2-picrylhydrazyl (DPPH) and AlamarBlue methods, respectively. The result showed that FD extract provided the highest antioxidant activity with inhibition of 49.36% at 200 ppm of DPPH. Variation of fermentation time (3-21 days) demonstrated the highest activity with inhibition of 66.97% for antioxidant assay (7 days) and 81.13% for cytotoxic assay (3 days). FTIR analysis presented the existence of hydroxyl groups O-H (3452.58 cm-1), C=C groups (1668.43 cm-1); C-O hydroxyl group (1230.58 cm -1), and C-H sp3 groups (2941.44 cm-1). Based on LC-MS analysis, FD extract has a mass of m/z 305.63, [M+H]+, predicted as dihydroquercetin (C15H24O7). Keywords: Antioxidant assay, cytotoxic assay, endophytic fungi, colt coral, DPPH method, AlamarBlue method

The effective reduction of graphene oxide films using RF oxygen plasma treatment

Graphene Oxide (GO) has attracted strong research interest due to its unique mechanical, thermal, electrical, and magnetic properties. Herein, a simple oxygen plasma process is used as an eco-friendly, novel and effective surface treatment technique to enhance the microstructure, adhesion force, and electrical properties of the GO films. GO films were treated in a plasma oxygen environment at a constant RF power of 300 W and different processing times ranging from 0 to 7 min. X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy are utilized to examine changes in the type of surface groups and the distribution of bonds energy before and after plasma treatment. Additionally, the effect of RF oxygen plasma treatment on other properties, such as thermal stability, surface roughness, contact angle, work of adhesion, wettability, electrical conductivity, and sheet resistance has been studied. XPS data revealed that RF oxygen plasma treatment reduced the amount of oxygen-containing groups (such as epoxides (O–CO), carbonyls (C–O–C), and carboxyl's (O–CO) from 48.8% for the as-prepared GO film to 33.56% after 5 min of treatment. In addition, the average surface roughness (Ra) increased from ~7.8 of as-prepared GO film to ~8.7 μm, while the work of adhesion improved to reach 134.84 mN/m. However, with increasing plasma processing time up to 7 min, the thermogravimetric analysis (TGA) of the treated GO film showed a weight loss difference of 51.66%. Furthermore, introducing a high amount of CO bonds (carbonyl and SP2 groups of carbon atoms) after plasma treatment improved the electrical conductivity to a value of 0.156 S/m. The current results indicate that the properties of GO can be tuned by varying the degree of oxidation, which may pave the way for new developments in GO-based applications.

Oxygen migration induced effective magnetic and resistive switching boosted by graphene quantum dots

Graphene materials have attracted considerable research interest owing to their applications in memristor and prospective spintronic devices. In this work, the bifunctional resistive and magnetic switching effect is investigated in Ag/graphene quantum dots (GQDs): graphene oxide (GO)/ITO device: (1) In the low-resistance state, the conductive filaments are formed by oxygen migration away inducing the C–C sp2 groups. (2) In the high-resistance state, the directions of magnetic moment align by increasing the C–O sp3 group. The resistive switching ratios and saturation magnetization of GQDs memristor are shown to be approximately 20 and 2.2 times higher than that of GQDs-free memristor, respectively. Tunable magnetic switching makes GO-based memristive devices boosted by GQDs a promising candidate to future voltage-controlled, low-power, and high-density spintronics devices.

Effects of Long-Term Supplementation with Brown Seaweeds and Polyphenols in Rabbit on Meat Quality Parameters

Simple SummarySafe and natural feed supplement are required to enhance animal health and welfare, answering to the agri-food system and consumers’ needs. The research for sustainable feed additives for enhancing rabbit health and meat quality parameters are needed. Plants received considerable consideration as safe feed supplements in animal nutrition. Recent studies indicated that seaweed can be considered a sustainable dietary supplement that improve animals’ health and meat quality parameters. Moreover, plant polyphenols have been studied as antioxidants and cholesterol-lowering agents in meat. No data on the effects of long term dietary supplementation of a mixture composed of brown seaweed and plant polyphenols has been available. For this reason, we decided to test the effects of dietary natural supplements in rabbits, based on performance and meat quality parameters.The objective of the present study was to evaluate the effects of dam and offspring dietary supplementation with a natural feed additive on the growth performance and meat quality parameters of growing rabbits. The growing rabbits are selected from lactating does receiving a control diet (C) or diets supplemented with 0.3% (SP1) and 0.6% (SP2) of feed additive containing brown seaweeds (Laminaria spp.) and plant extracts. In the postweaning phase, the growing rabbits remained in the treatment group defined by their does and the trial lasted 42 days. The average daily feed intake and feed conversion ratio were improved in the rabbit fed 0.6% of the natural feed additive. The cholesterol content tended to be lower in Longissimus lumborum (LL) muscle and decrease in Semimembranosus (SM) muscle (in SP2 −41.36% than controls). The α tocopherol and retinol content were enhanced in both muscles of rabbit fed the natural mixture (SP1 and SP2 groups). An improvement of sensory attributes of texture was observed in both muscles from rabbit fed natural mixture. In conclusion, long term supplementation of both lactating does and offspring with the high dosage of brown seaweed and plant polyphenols improves growth performance and enhances meat nutritional and sensory parameters.

Effects of partial substitution of nitrites with purple-fleshed sweet potato powder on physicochemical characteristics of sausages

Synthetic nitrite imparts a reddish-pink color to meat and a distinct flavor to meat products, delays lipid oxidation, and inhibits microbial growth and pathogens. However, excessive intake of nitrite might result in the production of carcinogenic nitrosamine, which might increase the risk of cancer in humans. Therefore, we aimed to find an alternative natural colorant for pork sausages. Pork sausages were mixed with 0.014% sodium nitrite (NaNO2) alone (CON), without either NaNO2 or purple-fleshed sweet potato powder (PP; CON1), 0.5% PP alone (PP1), 1% PP (PP2) alone, 0.011% NaNO2 and 0.5% PP (SP1), and 0.011% NaNO2 and 1% PP (SP2). The sausages were then cooked and stored for physicochemical analysis on days 0, 5, 10, 15, and 20. The a* and W* values were the greatest and lowest in the SP2 and CON1 treatments, respectively (p < 0.05). The concentrations of residual nitrite in the sausages at 20 days decreased in the order of CON > SP1, SP2 > PP2 > PP1, CON1. The fatty acid content was higher, and flavorous amino acids were more in PP2 (p < 0.05). The fatty acid composition was comparable between the SP2 and CON groups, but the contents of glutamic acid and alanine were greater in the SP2 group. In conclusion, SP2 (0.011% NaNO2 with 1% PP) could be added as a natural colorant for pork sausage production, and NaNO2 could be substituted with up to 20% PP without detrimental effects on sausage appearance and/or quality.

Advanced oxidative degradation of acetaminophen by carbon catalysts: Radical vs non-radical pathways

Two representative carbon catalysts, granular activated carbon (GAC) and carbon nanotube (CNT) were selected for the degradation of acetaminophen (ACT) by persulfate (PS) activation. In this study, the materials characterization study indicated that the surface functional groups and surface area of the GAC were more abundant and larger, respectively, than the CNT. Whereas the contribution of sp2 and CO groups of the CNT was superior to the GAC; the structural defect levels and surface charging characteristics (pHPZC) were similar in both. The mass-based pseudo-first-order reaction rate constant of the CNT was 1.5 m−1 g−1, which was 50 times higher than that of the GAC (0.03 m−1 g−1). Radical and non-radical pathways were evaluated for catalytic reactions by the GAC/PS and CNT/PS systems, respectively. Experimental results using scavenger tests, linear voltammetry, and electron spin resonance (ESR) showed that the radical pathway was dominant in the GAC/PS system, whereas the non-radical pathway was dominant in the CNT/PS systems. To confirm this, the influence of affecting factors such as initial ACT concentration, the dosage of oxidant (PS), and initial pH were also investigated and compared for the two systems. The results showed that the catalytic activity of the GAC/PS system was highly dependent on initial concentrations of ACT and PS, while these were less influential in the CNT/PS system. The removal efficiency of ACT was not affected under a pH of 3–7 in both systems. Reusability experiments were conducted five times, and both the CNT/PS and GAC/PS systems demonstrated that the removal rate of ACT did not notably decrease with the number of experiment repetitions. This means that the application of a carbon catalyst to treat pharmaceutical contaminants in wastewater is effective.

Synthesis of Carbon Quantum Dot Nanoparticles Derived from Byproducts in Bio-Refinery Process for Cell Imaging and In Vivo Bioimaging.

The carbon quantum dot (CQD), a fluorescent carbon nanoparticle, has attracted considerable interest due to its photoluminescent property and promising applications in cell imaging and bioimaging. In this work, biocompatible, photostable, and sustainably sourced CQDs were synthesized from byproducts derived from a biorefinery process using one-pot hydrothermal treatment. The main components of byproducts were the degradation products (autohydrolyzate) of biomass pretreated by autohydrolysis. The as-synthesized CQDs had a size distribution from 2.0–6.0 nm and had high percentage of sp2 and sp3 carbon groups. The CQDs showed blue-green fluorescence with a quantum yield of ~13%, and the fluorescence behaviors were found to be stable with strong resistance to photobleaching and temperature change. In addition, it is found that the as-synthesized CQDs could be used for imaging of cells and tumors, which show potential applications in bioimaging and related fields such as phototherapy and imaging.

Selectivity Tuning of Graphene Oxide Based Reliable Gas Sensor Devices by Tailoring the Oxygen Functional Groups: A DFT Study Based Approach

This paper concerns the selectivity tuning of graphene oxide based gas sensor devices, where the role of oxygen functional groups like, carboxyl, carbonyl, hydroxyl (sp2), epoxy, and hydroxyl (sp3) were investigated for physisorption of NO2, NH3, CO, and H2O using first principle calculation (density functional theory) incorporating Atomistix Toolkit (v2015.1). Among the five functional groups under consideration, carboxyl, carbonyl, and hydroxyl (sp2) were considered at the edges on the basal plane, while epoxy and hydroxyl (sp3) groups were considered in the plane perpendicular to that. For all the species, the optimum positions for adsorption, adsorption energy and charge transfer efficiency were investigated for the above two planes. It was found that edge carboxyl group is the most favorable in terms of adsorption energy and charge transfer efficiency targeting NH3, CO, and H2O. On the contrary, for NO2, hydroxyl functionalization was found to be the most efficient one.

Effect of sevoflurane preconditioning on brain injury induced by cardiopulmonary bypass in rats

Objective To evaluate the effect of sevoflurane preconditioning on brain injury induced by cardiopulmonary bypass(CPB)in rats. Methods Forty adult male Sprague-Dawley rats, aged 6-8 months, weighing 350-450 g, were randomly divided into 5 groups(n=8 each)using a random number table: sham operation group(S group), CPB group, and preconditioning with different concentrations of sevoflurane groups(SP1, SP2 and SP3 groups). In SP1, SP2 and SP3 groups, sevoflurane with the final concentrations of 1.2%, 2.4% and 3.6%, respectively, was inhaled for 1 h, and then CPB was started.After sevoflurane preconditioning and before CPB(T0), at 30 min of CPB(T1), at the end of CPB(T2), and at 1, 2 and 3 h after termination of CPB(T3-5), venous blood samples were collected from the right internal jugular vein for determination of serum S100-β protein concentrations by enzyme-linked immunosorbent assay.Rats were sacrificed at T5, and hippocampi were isolated for determination of neuronal apoptosis(by TUNEL)and NF-κB p65 expression(by immunohistochemistry). Results Compared with group S, the concentration of serum S100-β protein was significantly increased at T1-5, the number of apoptotic neurons was significantly increased, and the expression of NF-κB p65 was significantly up-regulated in CPB, SP1, SP2 and SP3 groups(P<0.05). Compared with group CPB, the serum S100-β protein concentration was significantly decreased at T1-5, the number of apoptotic neurons was significantly decreased, and the expression of NF-κB p65 was significantly down-regulated in SP1, SP2 and SP3 groups(P<0.05). Compared with group SP1, the serum S100-β protein concentration was significantly decreased at T1-5, the number of apoptotic neurons was significantly decreased, and the expression of NF-κB p65 was significantly down-regulated in SP2 and SP3 groups(P<0.05). Compared with group SP2, the serum S100-β protein concentration was significantly decreased at T1-5, the number of apoptotic neurons was significantly decreased, and the expression of NF-κB p65 was significantly down-regulated in group SP3(P<0.05). Conclusion Sevoflurane preconditioning can attenuate CPB-induced brain injury probably by inhibiting activation of NF-κB in hippocampal neurons of rats. Key words: Anesthetics, inhalation; Ischemic preconditioning; Cardiopulmonary bypass; Brain injuries

Effects of sodium pyruvate on ameliorating metabolic acidosis

Objective To examine the effects of sodium pyruvate (SP) on metabolic acidosis. Methods For the in vivo experiments, we evaluated effects of SP on an ammonium chloride (NH4Cl)-induced hyperchloremic acidosis rat model. SP was infused at overall doses of 2, 4, and 6 mmol·kg− 1 for the SP1, SP2, and SP3 groups, respectively. Treatment with sodium bicarbonate (SB) was used as a positive control (2 mmol·kg− 1), and treatment with normal saline (NS) was used as a volume control (2 mL·kg− 1). Blood was sampled from the ophthalmic venous plexus for pH, blood gases, electrolytes, glucose, creatinine (Cr), and urea analysis after injection. For the in vitro experiment, propionate was applied to induce intracellular acidosis in human endothelial cells. Intracellular pH (pHi) was fluorimetrically measured after the addition of SP. Results In the in vivo study, the pH of SP1 group showed no significant difference compared with that of the NS group. The SP2 and SP3 groups had a higher pH than the NS group (P < 0.01). The SP3 group had a higher pH than the SB group (P < 0.05) and SP1 group (P < 0.05). Moreover, SP treatment ameliorated the abnormality of calcium and decreased the blood potassium levels. The SP3 group had higher glucose levels than SP1 group (P < 0.05). No significant differences were observed between all the groups in the plasma Cr and urea levels. In the in vitro study, the pHi increased immediately after the addition of SP. Conclusion The data suggest that intravascular treatment with SP represents a novel therapeutic strategy to ameliorate metabolic acidosis.

Preparation of graphene oxide and characterisation using electron spectroscopy

Graphene oxide was prepared from commercial graphene powder (G) platelets of 8nm thickness by oxidation in ozone (G-O3) and low-energy (cold) glow air plasma in a pink region (G-PP). X-ray photoelectron spectroscopy (XPS) was applied for chemical characterisation of the atomic content and for obtaining quantitative information on C hybridisation. Reflection electron energy loss spectroscopy (REELS) was used for characterising the surface structure including the content of surface and bulk carbon atoms of sp2 and sp3 hybridisation.The G-O3 and G-PP graphene oxide samples contain a low amount of C sp3 bonds and carbon–oxygen groups in comparison to graphene oxide prepared by the “wet” chemical methods. Oxidation of commercial graphene platelets powder, especially in air plasma, leads to increasing surface C sp3 and significantly bulk C sp3 contributions, indicating intercalation by oxygen groups. The intensity ratio of the REELS π+σ C sp2 bulk to the C sp2 surface energy loss peaks, decreasing in the order G>G-O3>G-PP, indicates exfoliation of layers in G-O3 and G-PP by oxygen functional groups and water with decreasing average number of layers in graphene oxide nanostructures due to oxidation. Although, the “wet” chemical methods are more effective for oxidation leading to a larger amount of C sp3 and oxygen groups, the proposed methods of oxidation by ozonation and in air plasma are inexpensive, safe, effective, environmentally friendly and do not result in toxic chemical waste products.