Viable bacterial counts of the Pangasius catfish (Pangasianodon hypophthalmus), their responses to seasonal variations of physicochemical parameters, and bacterial counts of the cultured ponds.

Objectives: The study was undertaken to evaluate the influences of some physicochemical parameters and viable bacterial counts in cultured ponds (water and sediment) on the viable counts of the Pangasius catfish (Pangasianodon hypophthalmus) (gill and intestine) on a seasonal scale. Materials and Methods: Physicochemical parameters, viz., ambient temperature, water temperature, water transparency, pH of the pond waters, and viable bacterial counts of pond water, sediment, fish gills, and intestines, were monitored during four different seasons. The responses of viable counts of bacteria to the seasonal changes of physicochemical parameters were also assessed using redundancy analysis (RDA) and a heatmap coupled with the clustering analysis. Results: Except for fluctuations in air and water temperatures, the other two physicochemical parameters were almost stable throughout the study periods. The gills and water counts were relatively lower than those of the intestine and sediment. Pearson's correlation analysis established no significant correlations between the physicochemical parameters and viable bacterial counts. However, significant positive correlations were detected between the viable counts of water and sediment and between the gill and intestine. The RDA plot showed that, except in spring, the viable counts of a particular sample type were similar among the four locations. The results of permutation test showed that, individually none of the studied physicochemical parameters was significant; however, the seasons significantly affected the viable counts.

Changes in viable bacterial counts and physicochemical parameters of water used during live transportation of Pangasius catfish (Pangasianodon hypophthalmus) in Bangladesh.

Objective: The study was undertaken to assess the changes in viable bacterial counts and physicochemical parameters of water used during the live transportation of Pangasius catfish (Pangasianodon hypophthalmus). The correlations between the changing patterns of these parameters were also established. Materials and Methods: Water samples were collected every 2 h interval, plated onto agar plates for assesing viable bacterial counts. Physicochemical parameters, namely, water temperature, dissolved oxygen (DO), pH, and ammonia (NH3) concentration in the water were measured with a glass thermometer, DO test kit, pH test kit, and total NH3 measurement kit, respectively. Results: The viable bacterial counts increased significantly from 0 to 2 h in all the studied channels and remained almost similar up to the end of the supply channels. The water temperature was almost stable regardless of the supply channels and transportation period at around 30°C. The DO concentration and pH level decreased, and NH3 concentrations increased gradually in all the supply channels. The viable bacterial counts were inversely correlated to the DO levels and directly associated with the NH3 concentrations of the water used during the live transportation of Pangasius catfish. Conclusions: Gradual increase in viable bacterial counts and fluctuation in some vital physicochemical parameters with the duration of transportation indicated an unfavorable environment for the survival of Pangasius catfish.

Renoprotective potentials of small molecule natural products targeting mitochondrial dysfunction.

Kidney diseases, including acute kidney injury (AKI) and chronic kidney disease (CKD), have become critical clinical, socioeconomic, and public health concerns worldwide. The kidney requires a lot of energy, and mitochondria act as the central organelle for the proper functioning of the kidney. Mitochondrial dysfunction has been associated with the pathogenesis of AKI and CKD. Natural products and their structural analogs have been sought as an alternative therapeutic strategy despite the challenges in drug discovery. Many studies have shown that small-molecule natural products can improve renal function and ameliorate kidney disease progression. This review summarizes the nephroprotective effects of small-molecule natural products, such as berberine, betulinic acid, celastrol, curcumin, salidroside, polydatin, and resveratrol. Treatment with small-molecule natural products was shown to attenuate renal oxidative stress and mitochondrial DNA (mtDNA) damage and restore mitochondrial biogenesis and dynamics in the kidneys against various injury stimuli. Therefore, small-molecule natural products should be recognized as multi-target therapeutics and promising drugs to prevent kidney diseases, particularly those with mitochondrial dysfunction.