ABSTRACT
Salinity is an important abiotic stress that affects metabolic and physiological activities, breed, development, and growth of marine fish. Studies have shown that cobia (Rachycentron canadum), a euryhaline marine teleost fish, possesses the ability of rapid and effective hyper/hypo iono- and osmoregulation. However, genomic studies on this species are lacking and it has not been studied at the transcriptome level to identify the genes responsible for salinity regulation, which affects the understanding of the fundamental mechanism underlying adaptation to fluctuations in salinity. To describe the molecular response of cobia to different salinity levels, we used RNA-seq analysis to identify genes and biological processes involved in response to salinity changes. In the present study, 395,080,114 clean reads were generated and then assembled into 65,318 unigenes with an N50 size of 2758 bp. There were 20,671 significantly differentially expressed genes (DEGs) including 8805 genes adapted to hypo-salinity and 11,866 genes adapted to hyper-salinity. These DEGs were highly represented in steroid biosynthesis, unsaturated fatty acid metabolism, glutathione metabolism, energy metabolism, osmoregulation, and immune response. The candidate genes identified in cobia provide valuable information for studying the molecular mechanism of salinity adaptation in marine fish. Furthermore, the transcriptomic sequencing data acts not only as an important resource for the identification of novel genes but also for further investigations regarding cobia biology.
Subject(s)
Adaptation, Physiological/genetics , Perciformes/genetics , Salt Tolerance/genetics , Sequence Analysis, RNA , Animals , Gene Expression Regulation , Genetic Variation , Salt Tolerance/physiologyABSTRACT
The pigments in sugarcane result the crystallised sucrose appears unsatisfactorily yellow. In this study, cationic tapioca starch (CTS)-functionalized magnetic nanoparticles (CTS@Fe3O4) were synthesized and used as adsorbents for the removal of undesirable pigments. The adsorption properties of CTS@Fe3O4 were investigated by a sugarcane juice colorant model consisting of caffeic acid (CA), gallic acid (GA) and melanoidin (ME). The equilibrium adsorption capacities of CTS@Fe3O4 for CA, GA, and ME were 185, 160 and 580 mg g-1 at the optimal conditions (60, 60 and 180 mg L-1 initial concentrations, respectively; 0.3 mg mL-1 CTS@Fe3O4 dosage, 313 K temperature, and pH value of 7). The adsorption process was described well by second-order kinetic and Langmuir isotherm models with a high fitting correlation coefficient approaching 1, suggesting that the pigments formed a surface monolayer with a homogenously distributed adsorption energy and was mainly dominated by chemisorption. The thermodynamic parameters (Gibbs free energy <0, enthalpy >0, and entropy >0) revealed that the adsorption process was endothermic and spontaneous. For the binary system, the competitive adsorption between pigments was primarily antagonistic. The speed of adsorption was the main factor affecting competitive adsorption, and the additional adsorption force reduced the effects of coexisting adsorbates.
Subject(s)
Nanocomposites , Saccharum , Water Pollutants, Chemical , Adsorption , Thermodynamics , Cations , Nanocomposites/chemistry , Kinetics , Magnetic Phenomena , Water Pollutants, Chemical/chemistryABSTRACT
The development of adsorbents with outstanding adsorption capacities, wide versatility, and excellent recyclability for the removal of organic dyes remains a challenge. In this study, a quaternised chitosan-based aerogel (QCSA) was fabricated via a facile method to effectively treat concomitant anionic dyes. Porous QCSA with high hydrophilicity, nontoxicity, excellent thermal stability, and sustainability exhibits adsorption properties superior to most previously reported adsorbents. The equilibrium adsorption capacities for Congo red, Sunset yellow, and Methyl orange were 1259.6, 550.2, and 607.5 mg/g, respectively. Notably, the spent QCSA exhibits excellent cyclic performance. The multilayer adsorption, external-internal mass transfer resistance, and adsorption on the active site models were employed to enable a more accurate description of the dynamic characteristics, confirming that double-layer chemisorption was the dominant process. A quantitative analysis of the electrostatic potential and the independent gradient model further verified that electrostatic interactions, hydrogen bonding, and van der Waals forces led to the highly efficient adsorption of dye molecules. Therefore, the eco-friendly and recyclable QCSA is a promising adsorbent for trapping anionic dyes from aquatic systems.
ABSTRACT
Camellia oil is an edible health oil with high medicinal value. While phospholipids, peroxides, and free fatty acids are present in unrefined camellia virgin oil (CVO), which has a negative impact on the quality characteristics and storage stability. This paper is to investigate the testing effects of transmembrane pressure and temperature on the membrane flux and degumming (the removal of colloidal substances from crude oil and which is mainly phospholipids) to determine the optimum process parameters for the purification of CVO. On this basis, the effects of purification treatments applied by using a membrane system with membranes of different pore sizes (200, 140, 20, 15, and 10 nm) on CVO were tested. The results indicate that the purification treatments of ceramic membrane on CVO reduced the contents of phospholipids (87.0% reduction), peroxides (29.2% reduction), and free fatty acids (16.2% reduction) at a transmembrane pressure of 0.4 MPa and temperature of 60 °C. At the same time, these treatments did not significantly alter the fatty acid composition. Thus, ceramic membranes have the potential for the purification of camellia oil, which could be an effective way to achieve the purification of camellia oil.
ABSTRACT
The vegetable oil industry is limited by the high cost of the refining process, and the camellia shells (CS) are beneficial to the development of the industry as a biomass raw material for camellia oil decolorization. In this study, CS-based p-doped porous activated carbon (CSHAC) obtained after the pyrolysis of H3PO4-laden CS-hydrochar (CSH) was used for the adsorption of carotenoids in camellia oil. The results showed that the adsorption efficiency of CSHAC for carotenoids was 96.5% compared to 67-87% for commercial decolorizers, and exhibited a fast adsorption rate (20 min). The results of adsorption isotherms indicated that the adsorption of carotenoids on CSHAC occurred through a multi-layer process. Furthermore, the analysis of adsorption kinetics showed that the adsorption of carotenoids by CSHAC was a complex process involving physical and chemical reactions, and chemisorption was the dominant kinetic mechanism. This superior performance of CSHAC in adsorbing carotenoids was attributed to its micro-mesoporous structure, hydrophobicity, and numerous active sites.