Search

This study utilizes a natural air diffusion cathode (ADC) and an ultraviolet lamp to construct a UV/H2O2 reactor for the in situ synthesis and activation of H2O2 and evaluates its potential application in practical lake water treatment. The results indicate that the reactor exhibits stable treatment performance during a continuous flow experiment of 80 h. The air diffusion cathode maintains an H2O2 concentration of above 350 mg·L−1 in sodium sulfate electrolyte and shows no decreasing trend. Under the condition of approximately 59% H2O2 utilization, the removal rates of COD and TOC are 37.6% and 40.0%, respectively; the rate of reduction of A254 is 64.3%; while the total bacterial count removal rate reaches 100%. Large organic molecules in surface water are degraded to small organic molecules and mineralized to inorganic minor molecules. It effectively ameliorates the problem of organic pollution of surface water and effectively kills bacteria and improves the microbiological safety of the water body. Therefore, the UV/H2O2 system developed in this study, based on electrochemically produced H2O2, is an effective method for treating micro-polluted surface water. [ABSTRACT FROM AUTHOR]

Simple Summary: An excessive carbohydrate content in diets can have a negative effect on fish growth. In this study, the effects of berberine supplementation in high-carbohydrate diets on the growth performance, glucose metabolism, bile acid synthesis, liver transcriptome, and intestinal flora of Nile tilapia were investigated. Conclusion: An appropriate amount of berberine can stimulate the synthesis of bile acids by changing the structure of the intestinal flora of tilapia, thus promoting glycolysis and inhibiting gluconeogenesis, then regulating the blood glucose, which is beneficial to the growth of tilapia. This provides the data to improve carbohydrate utilization in tilapia and support the development of high-carbohydrate diets in aquaculture. Berberine is an alkaloid used to treat diabetes. This experiment aimed to investigate the effects of berberine supplementation in high-carbohydrate diets on the growth performance, glucose metabolism, bile acid synthesis, liver transcriptome, and intestinal flora of Nile tilapia. The six dietary groups were the C group with 29% carbohydrate, the H group with 44% carbohydrate, and the HB1-HB4 groups supplemented with 25, 50, 75, and 100 mg/kg of berberine in group H. The results of the 8-week trial showed that compared to group C, the abundance of Bacteroidetes was increased in group HB2 (p < 0.05). The cholesterol-7α-hydroxylase (CYP7A1) and sterol-27-hydroxylase (CYP27A1) activities were decreased and the expression of FXR was increased in group HB4 (p < 0.05). The pyruvate carboxylase (PC) and phosphoenolpyruvate carboxykinase (PEPCK) activities was decreased in group HB4 (p < 0.05). The liver transcriptome suggests that berberine affects carbohydrate metabolic pathways and primary bile acid synthesis pathways. In summary, berberine affects the glucose metabolism in tilapia by altering the intestinal flora structure, enriching differentially expressed genes (DEGs) in the bile acid pathway to stimulate bile acid production so that it promotes glycolysis and inhibits gluconeogenesis. Therefore, 100 mg/kg of berberine supplementation in high-carbohydrate diets is beneficial to tilapia. [ABSTRACT FROM AUTHOR]

Simple Summary: The ingestion of higher-lipid diets by fish could lead to excessive lipid deposition and metabolic disorders in vivo. This experiment analyzed the effects of steroidal saponins on hepatic glucose and lipid metabolism in hybrid grouper fed higher-lipid diets using a multi-omics approach. Data from grouper fed diets with 0% and 0.1% steroidal saponins show that 0.1% steroidal saponins inhibited glycogen synthesis, gluconeogenesis, and the arachidonic acid metabolism pathway and activated glycogenolysis, glycolysis, and the fatty acid β-oxidation pathway. This study provides a deeper insight into the glycolipid metabolic processes in the liver of grouper fed higher crude-lipid diets. An analysis of the extent of the effect of steroidal saponin addition on glucose and lipid metabolism in hybrid grouper liver was performed at the transcriptomic and metabolomic levels. Feeds (52% crude protein, 14% crude lipid) were prepared containing 0% (S0), 0.1% (S0.1), and 0.2% (S0.2) steroidal saponins. After eight weeks of feeding trial, compared to the S0 group, the activities of serum albumin, alanine aminotransferase, and aspartate transaminase were significantly lower and the activities of lysozyme, acid phosphatase, and alkaline phosphatase were significantly higher in the S0.1 group (p < 0.05). The superoxide dismutase, catalase, and glutathione peroxidase activities in the livers of the S0.1 group were significantly higher than those of the S0 group, while the malondialdehyde content was significantly lower than that of the S0 group (p < 0.05). There were forty-two differentially expressed genes and thirty-two differential metabolites associated with glucose and lipid metabolism enriched using KEGG and GO. In the S0 group, the expression of prostaglandin-endoperoxide synthase 1, prostaglandin E synthase 1, and thromboxane-2 synthase mRNA was significantly higher than in the S0.1 group (p < 0.05). The expression levels of genes in the S0 group were significantly higher than those in the S0.1 group (p < 0.05), including for glycogen synthase kinase, glucose-6-phosphatase catalytic subunit 2, fructose-1,6-bisphosphatase, phosphoenolpyruvate carboxykinase, glucose transporter 4, and malate dehydrogenase. The expression of mRNA such as fatty acid synthase, acetyl-CoA carboxylase, and sterol regulatory element-binding protein 1 was significantly lower in the S0.1 group than in the S0 group, while the expression of carnitine acyltransferase 1, acyl-CoA synthetase, and acyl-CoA dehydrogenase genes was significantly higher in the S0 group (p < 0.05). In summary, glycogen synthesis, gluconeogenesis, and the arachidonic acid metabolism pathway were inhibited by 0.1% steroidal saponins, and glycogenolysis, glycolysis, the tricarboxylic acid cycle, and the fatty acid β-oxidation pathway were activated. This study aims to provide a reference for the formulation of grouper feeds with a higher crude-lipid level. [ABSTRACT FROM AUTHOR]

Simple Summary: Due to the scarcity of fishmeal resources, alternatives that provide the necessary nutrients for Litopenaeus vannamei are being sought. While fishmeal has been the main nutrition source of Litopenaeus vannamei due to its rich nutrients, the search for protein sources to replace it is becoming increasingly important. The protein derived from Clostridium autoethanogenum protein shows great potential as a substitute for fishmeal owing to its exceptional nutritional value. However, previous studies have suggested that the growth of Litopenaeus vannamei may be adversely affected by the fishmeal replacement of Clostridium autoethanogenum protein. Research has demonstrated that chenodeoxycholic acid can improve the growth and intestinal health of Litopenaeus vannamei. Five diets were formulated with varying concentrations of chenodeoxycholic acid to feed Litopenaeus vannamei. The results revealed that replacing partial fishmeal with Clostridium autoethanogenum protein and adding 0.06% chenodeoxycholic acid led to significant improvements in the growth performance, lipid metabolism, and sterol metabolism. Additionally, the hepatopancreas health of the Litopenaeus vannamei was also improved. The conducted experiment has set the groundwork for further investigation into determining the most effective quantity of chenodeoxycholic acid to be utilized in low fishmeal diets. The study aimed to assess the impact of adding chenodeoxycholic acid (CDCA) to the diet of Litopenaeus vannamei on their growth performance, lipid and cholesterol metabolism, and hepatopancreas health while being fed a low fishmeal diet. Five diets were formulated, one of which contained 25% fishmeal (PC); fishmeal was partially replaced with Clostridium autoethanogenum protein in the remaining four diets and supplemented with 0, 0.03, 0.06, and 0.09% CDCA (NC, BA1, BA2, and BA3, respectively). In this study, four replicates of each diet were assigned and each replicate consisted of 30 shrimp with an average weight of (0.25 ± 0.03 g). The shrimp were fed four times a day for a period of 56 days. The results of this study indicate that the inclusion of CDCA in the diet had a positive impact on the growth performance of the shrimp. The final body weight (FBW), weight gain (WG), and specific growth rate (SGR) of the shrimp in the PC group were similar to those in the BA2 group, and significantly higher than those in the other three groups. The survival rate (SR) was similar among all groups. In comparison to the PC group, the low fishmeal groups exhibited a significant decrease in the crude lipid content of the whole shrimp, as well as the Total cholesterol (T-CHOL), Low-density lipoprotein (LDL-C), and High-density lipoprotein (HDL-C) levels in the hemolymph. Regarding the sterol metabolism, the dietary supplementation of CDCA up-regulated the mRNA expression of intracellular cholesterol transporter 1-like (npc1), 7-dehydrocholesterol reductase (7dhcr), Delta (24) sterol reductase (Δ24), HMG-CoA reductase membrane form (hmgcr), and sterol carrier protein 2 (scp). In the lipid metabolism, the mRNA expression of sterol-regulatory element binding protein (srebp) was significantly down-regulated in the shrimp fed the BA1 diet and the expression of AMP-activated protein kinase (ampk) was significantly up-regulated in the shrimp fed the BA1 and BA3 diets compared to the PC group. The mRNA expression of triacylglycerol lipase (tgl) was significantly up-regulated in the shrimp fed the BA2 diet compared to the NC group. Compared with the shrimp fed the PC diets, the dietary supplementation of CDCA significantly down-regulated the protein expression of SREBP1. The lumen damage in the BA1 group was significantly less severe than those in the NC group. The addition of 0.06% CDCA to low fishmeal diets can improve the growth performance, lipid and cholesterol metabolism, and hepatopancreas health of L. vannamei. [ABSTRACT FROM AUTHOR]

Simple Summary: With the development of the breeding industry, the production of fishmeal will not be able to meet the needs of feed production in the future. Clostridium autoethanogenum protein meal (CAP) is a by-product of people using carbon monoxide exhaust from the steel industry to produce ethanol, with a potential to become a substitute ingredient for fishmeal to alleviate the shortage of fishmeal. This study was conducted on pearl gentian grouper (Epinephelus fuscoguttatus ♀ × Epinephelus lanceolatus ♂), an economic fish species widely cultured in Southeast Asia. After using different concentrations of CAP to replace fishmeal in the feed for eight weeks, respectively, we found that it could replace 45% of fishmeal in the pearl gentian grouper feed through growth performance, various physiological and biochemical indexes analysis experiments, but a 60% replacement level would significantly affect health and growth. These findings provide a reference for the promotion and further research of CAP as a new environmentally friendly ingredient, which is positive for the sustainable development of the farming industry and even for the utilization of waste gas from the steel industry. In this study, we present data from an eight-week growth trial with pearl gentian grouper fed either a reference diet (FM) with a fishmeal level of 50%, or test diet wherein 15% (CAP15), 30% (CAP30), 45% (CAP45), and 60% (CAP60) fishmeal was replaced by Clostridium autoethanogenum protein meal (CAP). Results showed that the weight gain and daily feed intake ratio of CAP60 were significantly lower than the FM group. In the serum, compared to the FM group, the content of malondialdehyde (MDA), the activities of alanine aminotransferase in CAP60 and CAP45 groups, and acid phosphatase in the CAP60 group were significantly higher, while the content of total cholesterol in CAP60 and CAP45 groups was significantly lower. In the liver, compared to the control group, the content of MDA in the CAP60 group was significantly higher. 3-hydroxy-3-methylglutaryl coenzyme A reductase in CAP30 to CAP60 groups and farnesoid X receptor in CAP60 were significantly upregulated. In distal intestines, the activities of trypsin and superoxide dismutase of CAP30 to CAP60 groups were significantly lower than the FM group. In conclusion, for pearl gentian grouper, CAP could replace up to 45% of the fishmeal in the feed, while a 60% replacement level will affect cholesterol bile acid metabolism and health. [ABSTRACT FROM AUTHOR]

Simple Summary: There have been few studies on the effects of compound feed attractants on the growth mechanism and health of aquatic animals. This study aimed to investigate the effects of compound feed attractants on the growth performance, feed utilization, intestinal histology, protein synthesis, and immune response of Litopenaeus vannamei. Seven diets were formulated, and shrimp (0.71 ± 0.00) g were distributed to seven groups of four replicates and fed for 7 weeks. In this study, diet supplemented with squid visceral powder, fish soluble, squid paste, and shrimp paste, and a diet supplemented with yeast extract, squid visceral powder, squid paste, and shrimp paste promoted the feed intake and growth performance and enhanced the antioxidative ability of L. vannamei. The combination of squid visceral powder, fish soluble, squid paste, and shrimp paste not only increased the protein synthesis, but also promoted the hepatopancreas and intestinal response of shrimp. Conversely, the diet supplemented with yeast extract, squid visceral powder, fish soluble, and shrimp paste may have some negative effects on the hepatopancreas and intestine of L. vannamei. To investigate the effects of compound attractants on the growth performance, feed utilization, intestinal morphology, protein synthesis, and immune response of Litopenaeus vannamei, the following seven diets were formulated: a positive control (P), a negative control (N), and five diets with compound attractants which were labeled as A, B, C, D, and E, each with four of five tested attractants (yeast extract, squid visceral powder, fish soluble, and squid paste, shrimp paste), respectively. Shrimp (0.71 ± 0.00 g) were distributed to seven groups of four replicates and fed for 7 weeks. Results showed that the final body weight, feed intake, specific growth rate, and weight gain of shrimp in the B and D groups were the greatest. Hemolymph total antioxidant capacity of shrimp in the B, D, and E groups reached the highest level. In the hepatopancreas, the activity of total nitric oxide synthase, malondialdehyde content, the expression levels of sod, myd88, eif4e2, and raptor in shrimp fed the B diet were the highest, and the highest levels of dorsal and relish were observed in the C group. In the intestine, intestinal muscle thickness and expression levels of toll and eif2α in the C group were the highest, while the highest expression level of sod and relish occurred in the B group. In summary, the B and E diets promoted the feed intake, growth performance and the antioxidant enzyme activity of L. vannamei. The C diet enhanced the protein synthesis of shrimp. Regression analysis indicated that the WG and FI of shrimp were increased as the dietary inclusion levels of squid paste and shrimp paste increased, while they were decreased as the dietary inclusion levels of yeast extract and fish soluble increased. [ABSTRACT FROM AUTHOR]

Titanium dioxide (TiO2) photocatalysis is a popular and promising technology in water treatment, but the performance evaluation usually depends on expensive equipment. In this study, using a smartphone for colorimetric detection, a self-invented method based on paper and microtubes (PMTs) is proposed to test the photocatalytic performance of TiO2. Firstly, the study has identified that PMTs achieved a correlation coefficient of above 0.9 between the greyscale values and concentrations during the physical process of different color dyes (i.e., rhodamine B (RhB), reactive yellow (RY), methylene blue (MB), and mixtures of the two or three dyes). The results indicate that when the principle of solution color follows the CMYK (Cyan, Magenta, Yellow, Black) color model, its photo color on white paper background conforms to the RGB (Red, Green, Blue) color model. Compared to the results obtained from the absorbance method, the PMTs method showed high reliabilities up to 99.36% on the monitoring of the photocatalytic process of the different dye solutions. Interestingly, the colorless solution of salicylic acid (SA) could also be analyzed by the PMTs after complexed with Fe(III) ion to develop a purple solution. These results suggest that the PMTs could be an alternative analysis method to evaluating physical and chemical reaction processes when the high-tech analysis equipment is unviable. [ABSTRACT FROM AUTHOR]

High-fat diet (HFD) usually induces oxidative stress and astaxanthin is regarded as an excellent anti-oxidant. An 8-week feeding trial was conducted to investigate the effects of dietary astaxanthin supplementation on growth performance, lipid metabolism, antioxidant ability, and immune response of juvenile largemouth bass (Micropterus salmoides) fed HFD. Four diets were formulated: the control diet (10.87% lipid, C), high-fat diet (18.08% lipid, HF), and HF diet supplemented with 75 and 150 mg kg−1 astaxanthin (HFA1 and HFA2, respectively). Dietary supplementation of astaxanthin improved the growth of fish fed HFD, also decreased hepatosomatic index and intraperitoneal fat ratio of fish fed HFD, while having no effect on body fat. Malondialdehyde content and superoxide dismutase activity were increased in fish fed HFD, astaxanthin supplementation in HFD decreased the oxidative stress of fish. The supplementation of astaxanthin in HFD also reduced the mRNA levels of Caspase 3, Caspase 9, BAD, and IL15. These results suggested that dietary astaxanthin supplementation in HFD improved the growth performance, antioxidant ability and immune response of largemouth bass. [ABSTRACT FROM AUTHOR]

Incorporating outstanding flame retardancy and electromagnetic interference shielding effectiveness (EMI SE) into polymers is a pressing requirement for practical utilization. In this study, we first employed the principles of microencapsulation and electrostatic interaction-driven self-assembly to encapsulate polyethyleneimine (PEI) molecules and Ti 3 C 2 T x nanosheets on the surface of ammonium polyphosphate (APP), forming a double-layer-encapsulated structure of ammonium polyphosphate (APP@PEI@Ti 3 C 2 T x ). Subsequently, flame-retardant thermoplastic polyurethane (TPU) composites were fabricated by melting the flame-retardant agent with TPU. Afterwards, by using air-assisted thermocompression technology, we combined a reduced graphene oxide (rGO) film with flame-retardant TPU composites to fabricate hierarchical TPU/APP@PEI@Ti 3 C 2 T x /rGO composites. We systematically studied the combustion behavior, flame retardancy, and smoke-suppression performance of these composite materials, as well as the flame-retardant mechanism of the expansion system. The results indicated a significant improvement in the interface interaction between APP@PEI@Ti 3 C 2 T x and the TPU matrix. Compared to pure TPU, the TPU/10APP@PEI@1TC composite exhibited reductions of 84.1%, 43.2%, 62.4%, and 85.2% in peak heat release rate, total heat release, total smoke release, and total carbon dioxide yield, respectively. The averaged EMI SE of hierarchical TPU/5APP@PEI@1TC/rGO also reached 15.53 dB in the X-band.