Tianjin Agricultural University

About: Tianjin Agricultural University is a education organization based out in Tianjin, China. It is known for research contribution in the topics: Gene & Population. The organization has 2107 authors who have published 1496 publications receiving 11815 citations.

Effect of Catfish Bone Hydrolysate on the Quality of Catfish Sausage During Ambient Temperature (37 °C) Storage

Abstract: The purpose of this study was to evaluate the effect of catfish bone hydrolysate (CBH), at levels of 0.5, 1.0, 1.5 and 2.0%, on the quality of catfish sausage stored at ambient temperature (37 °C). The results showed that sausages with addition of CBH had lower pH, lower TVB-N and lower total plate count during storage. The lightness (L*), redness (a*) and yellow (b* ) values of sausages with CBH were lower than control before storage. During storage, the L* values of the sausages with CBH decreased significantly. The a* values and the b* values changed slowly. Samples with 1.5% CBH had higher overall acceptance during storage.

Influence of Microplastics on the Growth and the Intestinal Microbiota Composition of Brine Shrimp.

Abstract: Microplastics (MPs) are ubiquitous in the aquatic environment and can be frequently ingested by zooplankton, leading to various effects. Brine shrimp (Artemia parthenogenetica) has an important role in the energy flow through trophic levels in different seawater systems. In this work, the influence of polyethylene (PE) and polystyrene (PS) MPs on the growth of brine shrimp and corresponding changes of gut microbiota were investigated. Our results showed that the MPs remarkably reduced the growth rate of brine shrimp, and the two types of MPs have different impacts. The average body length of brine shrimps was reduced by 17.92 and 14.95% in the PE group and PS group, respectively. MPs are mainly found in the intestine, and their exposure evidently affects the gut microbiota. By using 16S rRNA gene high-throughput sequencing, 32 phyla of bacteria were detected in the intestine, and the microbiome consisted mainly of Proteobacteria, Firmicutes, and Actinobacteria. MPs' exposure significantly increased the gut microbial diversity. For the PE group, the proportion of Actinobacteria and Bacteroidetes increased by 45.26 and 2.73%, respectively. For the PS group, it was 54.95 and 1.27%, respectively. According to the analysis on genus level, the proportions of Ponticoccus, Seohaeicola, Polycyclovorans, and Methylophaga decreased by 46.38, 1.24, 1.07, and 2.66%, respectively, for the PE group and 57.87, 1.43, 0.88, and 2.24%, respectively, for the PS group. In contrast, the proportions of Stappia, Microbacterium, and Dietzia increased by 1.12, 23.27, and 11.59%, respectively, for the PE group, and 1.09, 3.79, and 42.96%, respectively, for the PS group. These experimental results demonstrated that the ingestion of MPs by brine shrimp can alter the composition of the gut microbiota and lead to a slow growth rate. This study provides preliminary data support for understanding the biotoxicity of MPs to invertebrate zooplankton and is conducive to the further risk assessment of MP exposure.

Antibacterial Activities of Antibacterial Proteins/Peptides Isolated from Organs and Mucus of Clarias Gariepinus Reared at High Stocking Density

Abstract: . Antibacterial proteins/peptides are important parts of the innate immune system in Clarias gariepinus. To examine potential antibacterial proteins/peptides in organs and mucus of C. gariepinus, crude protein/peptide extracts were isolated with ammonium sulfate precipitation from mucus, skin, gill, suprabranchial organ and intestine. Following further extraction using Sephadex G-50 gel filtration chromatography, the proteins/peptides associated with two absorption peaks (AP1 and AP2) were pooled, respectively, and assayed for their antibacterial activities against Escherichia coli, Aeromonas hydrophila and Edwardsiella tarda. The results showed that AP1 and AP2 from all the sampled tissues and mucus at concentration of 100 mg mL-1 exhibited antibacterial activity against the tested bacterial strains. Differences in antibacterial activity were observed among sample extracts. The protein profiles of AP1 obtained by Tricine-SDS-PAGE gel showed a broad range of peptides/proteins, and molecular weight of the mutual abundant peptide obtained was about 27 kDa. Antibacterial activity of AP2 extracted from intestine was due to peptide with molecular weight of 5.5 kDa.

Study on Livestock and Poultry Farming Wastewater Treatment Using a Hybrid Baffled Reactor

Abstract: In this paper aerobic process was applied in an anaerobic baffled reactor to form an innovative Hybrid Baffled Reactor (HBR), which was used to investigate the treatment effect of livestock and poultry farming wastewater. Biofilm cultivation, the influence of Hydraulic Retention Time (HRT) and treatment effect in three tanks were also discussed. The study result showed that good COD and NH4+-N removal efficiency was achieved in the reactor. When the influent COD concentration, NH4+-N concentration and HRT were 900 mg/L, 200 mg/L and 24 h, the concentrations of COD and NH4+-N in the outlet were smaller than 100 mg/L and 70 mg/L, and COD removal efficiency and nitrification rate were 90% and 70% respectively.