Chen B.,Fujian Normal University |
You W.,Fujian Normal University |
Huang J.,Fujian Normal University |
Yu Y.,Fujian Normal University |
And 2 more authors.
World Journal of Microbiology and Biotechnology | Year: 2010
The extracellular polysaccharide from Rhodella reticulata was separated from the culture medium followed by concentration and ethanol precipitation, and purified by anion exchange chromatography on DEAE-Sepharose Fast Flow. This study compared the free radical-scavenging property and antioxidant activity with various treatments of crude extracellular polysaccharides of R. reticulata. The results showed that both the crude extracellular polysaccharide and deproteinized crude extracellular polysaccharide gave evidence of the free radical scavenging and antioxidant activity in a dose-dependent manner. The crude extracellular polysaccharide exhibited higher free radical scavenging capacity and better antioxidant activity than the various treatments of crude extracellular polysaccharide samples. The superoxide anion radical scavenging ability of various samples was significantly higher compared to standard antioxidant (α-tocopherol). These results indicate that the extracellular polysaccharide of R. reticulata is a potent natural antioxidant. © Springer Science+Business Media B.V. 2009.
Shi X.,Xiamen University |
Zhang Z.,Xiamen University |
Qu M.,Xiamen University |
Ding S.,Xiamen University |
Zheng L.,Fisheries Research Institute of Fujian
Fish and Shellfish Immunology | Year: 2012
Leucocyte cell-derived chemotaxin 2 (LECT2) was first identified as a chemotactic factor and has been subsequently proven to be a multifunctional protein that mediates the regulation of liver regeneration, carcinogenesis and Natural killer T (NKT) cell homeostasis in mammals. In fish, it has been recently found to be critical for the inflammatory response to stimuli. However, the in vivo function of LECT2 in fish remains obscure. Base on the full-length cDNA of the Epinephelus akaraa LECT2 (EaLECT2) gene we previously isolated, we sought to analyze its genomic structure and context. The genomic DNA of the EaLECT2 gene spans 2866. bp from the transcription start site to the termination codon. As in most LECT2 genes in other vertebrates, the EaLECT2 genomic DNA contains four exons and three introns. An analysis of the promoter region revealed the presence of a TATA box and several putative transcription factor-binding sites. And transcriptional activity analysis suggested that most basal DNA regulatory elements required for EaLECT2 transcriptional activity might be contained within the 581. bp region upstream of the transcription start codon. A real-time PCR analysis showed that the EaLECT2 expression levels were slightly increased in the head kidney, liver, gill and brain by bacterial challenge with Vibrio harveyi. Furthermore, the transcriptional level of the EaLECT2 gene in the liver was significantly up-regulated within 1. h and reached its peak level at 12. h post-stimulation. Higher levels of LECT2 expression were also observed in head kidney in challenged individuals. The expression pattern demonstrates the role of EaLECT2 in the immune response and its functions under other conditions. Additionally, we found that the recombinant EaLECT2 could be expressed as a soluble protein using a prokaryotic expression system with the expression vector pET32a(+) and the soluble protein was further proved to be the recombinant EaLECT2 with the rat antiserum against EaLECT2 we obtained. This work provides a unique basis for substantial work in future projects. © 2012 Elsevier Ltd.
Wang Q.,Xiamen University |
Wang Q.,Fisheries Research Institute of Fujian |
Gao Z.-X.,Xiamen University |
Zhang N.,Fisheries Research Institute of Fujian |
And 3 more authors.
Journal of Agricultural and Food Chemistry | Year: 2010
Trypsin from the intestine of hybrid tilapia (Oreochromls niloticus x O.aureus) was purified by the following techniques: acetone precipitation, ammonium sulfate fractionation, Sephacryl S-200 gel filtration, and DEAE-sephacel ion exchange chromatography. The purified enzyme was determined to be homogeneous by Polyacrylamide gel electrophoresis (PAGE) and sodium dodecyl sulfate (SDS)-PAGE. The molecular weight was estimated as 22,000 Da. The optimum pH and temperature of the enzyme for the hydrolysis of casein were determined to be 9.0 and 60 °C, respectively. The enzyme was stable over a broad pH range from 7.0 to 12.0 at 30 °C, and the enzyme was inactive at temperatures above 50 °C. The behavior of the enzyme for the hydrolysis of casein followed Michaells-Menten kinetics with Km of 0.46 mg/mL. The purified enzyme was inhibited by the general serine protease inhibitor phenyl methyl sulphonyl fluoride (PMSF) and also by the specific trypsin Inhibitor N-p-tosyk-lysine chloromethyl ketone (TLCK) using Na-CBZ-L-lysine p-nitrophenyl ester hydrochloride (CBZ-Lys-pNP) as a substrate. The protease was inhibited by the following ions in decreasing order: Zn2+ > Fe3+ > Cu2+ > Al3+ > Co2+ = Pb2+ > Cd2+ > Mn2+. The ions Li +, Na+, K+, Mg2+, and Ba 2+ had little effect on the enzyme, and Ca2+ can partially promote its activity at low concentration. © 2009 American Chemical Society.
PubMed | Fisheries Research Institute of Fujian and Sun Yat Sen University
Type: Journal Article | Journal: Genetics and molecular research : GMR | Year: 2015
In the present study, ten novel microsatellite markers were developed from an enriched-(CA)13 genomic library of Epinephelus akaara. The mean number of alleles per locus was 21.6, with a range of 12 to 33. Observed heterozygosity ranged from 0.767 to 0.967, and expected heterozygosity ranged from 0.831 to 0.975, with mean values of 0.877 and 0.923, respectively. Among the ten loci, three loci deviated from Hardy-Weinberg equilibrium after sequential Bonferronis correction. These polymorphic microsatellite markers may be useful for studies on the population genetics of E. akaara.
PubMed | Jimei University and Fisheries Research Institute of Fujian
Type: Journal Article | Journal: Genome announcements | Year: 2017
Aeromonas sobria is a Gram-negative, rod-shaped, and ubiquitous bacterium. We present here the draft genome sequence of A.sobria strain 08005, isolated from an infected bullfrog. It is composed of 66 contigs totaling 4,678,951bp, contains 4,252 coding DNA sequences (CDSs), four rRNAs, and 88 tRNA sequences, and shows the presence of various putative virulence-related genes.
Chen H.,Fujian Agriculture and forestry University |
Chen H.,Xiamen Ocean Vocational College |
Liu Z.,Fujian Agriculture and forestry University |
Liu Z.,Fisheries Research Institute of Fujian |
And 3 more authors.
Journal of the Science of Food and Agriculture | Year: 2013
Background: The spoilage bacterial community in oyster gill was investigated during storage at 4, 10 and 20°C. Aerobic plate counts and pH values were determined. Total bacterial DNA was extracted from oyster gill and bulk cells of plate count media. The major bacterial species during fresh or different temperatures storage were determined by polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE). Results: The initial aerobic plate count in oyster gill reached 6.70 log CFU g-1. PCR-DGGE fingerprinting analysis of the 16S rRNA gene V3 region revealed that most of the strains in fresh oyster gill belonged to the genera Lactococcus and Enterobacter. The major spoilage bacteria at a storage temperature of 20°C were Leuconostoc pseudomesenteroides, an uncultured bacterium, Cytophaga fermentans, Lactococcus lactis, Pseudoalteromonas sp., Enterococcus mundtii, Clostridium difficile and an uncultured Fusobacteria; those at 10°C were Lactococcus spp., Lactobacillus curvatus, Weissella confusa and C. difficile; those at 4°C were Lactococcus, Weissella, Enterobacter and Aeromonas. The other minor species were L. curvatus, Pseudomonas sp. and E. mundtii. Lactococcus spp. was the most common main spoilage bacteria in oyster gill during chilled storage. Conclusion: PCR-DGGE revealed the complexity of the bacterial microbiota and the major bacteria species in oyster gill for fresh and storage. © 2013 Society of Chemical Industry.
Hsu T.-H.,National Taiwan Ocean University |
Ning Y.,Fisheries Research Institute of Fujian |
Gwo J.-C.,National Taiwan Ocean University |
Zeng Z.-N.,Fisheries Research Institute of Fujian
Molecular Ecology Resources | Year: 2013
Peanut worm (Sipunculus nudus) is a cosmopolitan species mainly distributed in tropical and subtropical coastal waters. Analysis of the mitochondrial cytochrome c oxidase subunit I (COI) gene sequences among S. nudus from GenBank revealed high genetic variation (p-distance, 0.115-0.235; k2p, 0.128-0.297) and paraphyletic relationships. These indicated misidentification and/or cryptic diversity may be present in the genus Sipunculus. To understand the genetic diversity and to manage the recourse of S. nudus, we collected specimens from coastal waters of southern China and Taiwan. In the phylogenetic topology, specimens can be separated into four distinct clades; three of these clades (clade A, B and C) were only represented from this region (southern China and Taiwan), but the clade D grouped with individuals from Central America (Atlantic coast). Furthermore, individuals of clades A and D were collected at the same location, which does not support the hypothesis that this genetic break reflects contemporary geographical isolation. The four distinct clades observed among coastal waters of southern China and Taiwan indicated underestimated diversity. It is noteworthy that the cryptic diversity is vulnerable under high pressure of human activity. © 2013 John Wiley & Sons Ltd.
Luo D.-L.,Fisheries Research Institute of Fujian
Chinese Journal of Applied Ecology | Year: 2011
Based on the ecological investigation data in September and October 2007, the status of the marine ecological environment of Nanri Archipelago, Fujian Province in summer was diagnosed and assessed from the aspects of sea water quality, nutrient structure and levels, and biodiversity. The comprehensive quality index method was used for the assessment of the marine ecological environment, and the rationality of the assessment obtained from different indices was also discussed. The sea water pH, dissolved oxygen (DO), chemical oxygen demand (COD), and Pb, Cd, Hg, and As concentrations were all within the limit values of the Grade E standard of Sea Water Quality Standard (GB 3097-1997), while the phosphate concentration at 71% stations, inorganic nitrogen at 14% stations, and oil concentration at 7% stations were all above the Grade E standard of Sea Water Quality Standard. Overall, the seawater quality was of better grade, nutrient structure was characterized by N-limited, most of the sea water was at a state of eutrophication, and the diversity index of plankton was at mildly polluted or unpolluted level. The comprehensive quality index indicated that the seawater quality of the Nanri Archipelago was relatively fine. There existed definite differences in the assessment results by using different diagnosis methods, and hence, a relatively objective assessment about marine environmental quality and health status could only be made when the chemical and biological indicators were comprehensively used.
Luo D.-L.,Fisheries Research Institute of Fujian
Chinese Journal of Applied Ecology | Year: 2014
The concentration, distribution and transfer of dichloro-diphenyl-tricgloroethanes(DDTs) in the surface layer water, sediments and aquatic organisms from the Zhangjiang River Estuary were investigated using GC-ECD method. The possible sources were assessed based on the distribution and composition characteristics of DDTs together with the investigation results of dicofol. The results showed that the concentration of DDTs in surface layer water ranged from ND (not detected) to 20.1 ng·L-1 with an average of 10.5 ng·L-1 in dry period, from ND to 45.2 ng·L-1 with an average of 28.3 ng·L-1 in wet period, and from ND to 18.8 ng·L-1 with an average of 5.03 ng·L-1 in level period. Concentration of DDTs in surface sediment (dry mass) ranged from 1.87 ng·g-1 to 144 ng·g-1 with an average of 17.3 ng·g-1, and that in 11 species of aquatic organisms ranged from 1.09 ng·g-1 to 432 ng·g-1 with an average of 37.0 ng·g-1. Compared to other areas, the residues of DDTs in the Zhangjiang River Estuary were at the medium level. The accumulation factors of DDTs in sediment and aquatic organisms were 1185 and 2534, respectively. The capacities for DDTs accumulation were in the order of fish>shellfish>shrimp>aquatic plants. The concentrations of DDTs showed downtrend along the Zhangjiang River, indicating that the residues of DDTs mainly came from terrigenous pollution rather than from the release of antifouling agent of ships. Based on the composition profile, DDTs mainly came from the early residues. However, the highest value of dicofol was recently detected both in the water and sediment of Y8 station, which suggested that new DDTs inputs at the Y8 station might be related to the recent usage of dicofol. ©, 2014, Editorial Board of Chinese Journal of Applied Ecology. All right reserved.
PubMed | Xiamen Ocean Vocational College, State Oceanic Administration, University of Guelph and Fisheries Research Institute of Fujian
Type: | Journal: Food microbiology | Year: 2016
As filter-feeding bivalves, oysters can accumulate microorganisms into their gills, causing spoilage and potential safety issues. This study aims to investigate the changes in the gill microbiota of oysters packed under air and modified atmospheres (MAs, 50% CO