Effect of Rhodopseudomonas sphaeroides–Treated Wastewater on Yield, Digestive Enzymes, Antioxidants, Nonspecific Immunity, and Intestinal Microbiota of Common Carp

Abstract

The employment of traditional bait and medicament in freshwater aquaculture causes the frequent occurrence of environmental pollution and disease. Effluent collected after wastewater treatment with Rhodopseudomonas sphaeroides could be reutilized for microbial feed, medicament, and aquaculture water to culture Common Carp Cyprinus carpio. Therefore, a novel integrated system of wastewater treatment and the use of the effluent containing R. sphaeroides, which could improve yield, increase disease resistance, and enhance the quality of aquaculture water for Common Carp culture, was proposed and investigated. Common Carp can grow well in effluent containing R. sphaeroides. The survival rate, yield, and whole‐body composition of the fish raised in effluent containing R. sphaeroides were all increased compared with the control group. The biochemical (B vitamin) and other substances in the effluent with R. sphaeroides enhanced the activity of proteases, amylases, lipases, alkaline phosphatase, acid phosphatase, phagocytes, superoxide dismutase, and catalase by up‐regulating the expression of their associated genes. Theoretical analysis showed that biochemical molecules regulate the expression of these gene and enzyme activities by acting as a signal that stimulates the active center. Moreover, biochemicals present in R. sphaeroides enhanced the mTOR and NF‐kB signaling pathways and improved intestinal microbiota. Furthermore, R. sphaeroides inhibited Aeromonas hydrophila, increasing resistance against fish disease and promoting the growth of intestinal bacteria. Meanwhile, R. sphaeroides in the effluent also improved the aquaculture water quality. This technology would simultaneously save water in aquaculture, reduce water pollution and wastewater discharge, and increase the output and disease resistance of Common Carp.

Weathering and degradation of polylactic acid masks in a simulated environment in the context of the COVID-19 pandemic and their effects on the growth of winter grazing ryegrass

“…Among them, the plant mortality of the population with the addition of PLA fiber treated with aquaculture water was significantly higher than that of other populations (DR=84.14%). It may be that the PLA fiber treated by the aquaculture water contains bacteriostatic agents and drugs that were added to the aquaculture water [46] , [47] , which may not be conducive to the growth of ryegrass because these drugs will remain in the water, and the MPs have a stronger ability to carry pollutants due to weathering. After the number of dead plants reached a peak, it started to decline, which may be due to the reduction in individual plants competing for space, water, nutrients, and other resources.…”

Addressing Phosphorus Waste in Open Flow Freshwater Fish Farms: Challenges and Solutions

“…Fish intestine morphometric characteristics, including the surface area, as well as the presence of specialized cells, can reveal an intriguing relationship between anatomy and nutrient absorption efficiency [45][46][47]. Fish possess a multitude of intestinal folds within their intestinal lining, and these fulfill a similar function to that of the mammalian intestinal villi, in that they augment the surface area available for nutrient absorption.…”

“…Another example involves the utilization of effluent collected after wastewater treatment with Rhodopseudomonas sphaeroides. This effluent can be reutilized for microbial feed, medicament, and aquaculture water, specifically for the culture of common carp [46]. The integrated system of wastewater treatment and the use of effluent containing R. sphaeroides offer several benefits for the culture of common carp.…”

“…Studies have shown that common carp raised in effluent containing R. sphaeroides exhibit improved survival rates, increased yield, and enhanced whole-body composition compared to those of the control groups. This effect is attributed to the presence of B vitamins in the effluent with R. sphaeroides, which enhance the activity of various enzymes and genes related to digestion, immunity, and antioxidant defense mechanisms [46]. Furthermore, the presence of R. sphaeroides in the effluent contributes to the improvement in aquaculture water quality, leading to reduced water pollution and wastewater discharge.…”

Effect of heating temperature on electrical properties and gel properties of carp surimi

“…As the largest carp farming and consumer country in the world at present, China's production and sales of carp reached 3.02 million tons in 2020, accounting for 80% of the world's total (Wu et al, 2019). Apart from its remarkable protein content, carp serves as an extremely palatable food item priced affordably, making it a favored choice among Chinese consumers (Liu et al, 2018).…”