The bioaccumulation of waterborne zinc in tissues of silver catfish (Rhamdia quelen) and its effect on biochemical parameters

Diet supplementation of organic zinc positively affects growth, antioxidant capacity, immune response and lipid metabolism in juvenile largemouth bass, Micropterus salmoides

Zn is an important trace element involved in various biochemical processes in aquatic species. An 8-week rearing trial was thus conducted to investigate the effects of Zn on juvenile largemouth bass (Micropterus salmoides) by feeding seven diets, respectively, supplemented with no Zn (Con), 60 and 120 mg/kg inorganic Zn (Sul60 and Sul120), and 30, 60, 90 and 120 mg/kg organic Zn (Bio30, Bio60, Bio90 and Bio120). Sul120 and Bio120 groups showed significantly higher weight gain and specific growth rate than Con group, with Bio60 group obtaining the lowest viscerosomatic index and hepatosomatic index. 60 or 90 mg/kg organic Zn significantly facilitated whole body Zn retention. Up-regulation of hepatic superoxide dismutase, glutathione peroxidase and catalase activities and decline of malondialdehyde contents indicated augmented antioxidant capacities by organic Zn. Zn treatment also lowered plasma aminotransferase levels while promoting acid phosphatase activity and hepatic transcription levels of alp1, acp1 and lyz-c than deprivation of Zn. The alterations in whole body and liver crude lipid and plasma TAG contents illustrated the regulatory effect of Zn on lipid metabolism, which could be possibly attributed to the changes in hepatic expressions of acc1, pparγ, atgl and cpt1. These findings demonstrated the capabilities of Zn in potentiating growth and morphological performance, antioxidant capacity, immunity as well as regulating lipid metabolism in M. salmoides. Organic Zn could perform comparable effects at same or lower supplementation levels than inorganic Zn, suggesting its higher efficiency. 60 mg/kg supplementation of organic Zn could effectively cover the requirements of M. salmoides.

Crest to Trough Cellular Drifting of Green-Synthesized Zinc Oxide and Silver Nanoparticles

Green nanotechnology facilitates the blooming of zinc oxide (ZnO) and silver (Ag) nanoparticles (NPs) with distinct flowerlike and spherical morphologies, respectively. The well-characterized NPs with an average size of 35 nm (ZnO) and 25 nm (Ag) were functionalized on the cresty plates for antibacterial inhibition against Staphylococcus aureus and Pseudomonas aeruginosa, with the flowerlike ZnONPs exhibiting 90.9% inhibition and AgNPs exhibiting 100% inhibition. Further, the in vivo underwater troughs for hematological, immunological, and serological analysis in Labeo rohita exhibited 102 > 575 > 104 and 206 > 109 > 81% at concentrations of 1, 2, and 3 mg/L with 4-day and 15-day treatment, respectively, over ZnONPs. However, AgNPs exhibited 257 > 408 > 124 and 86 > 202 > 43% with 4-day and 15-day treatment, respectively, at the same concentrations. The classical ZnNPs and AgNPs exhibited excellent inhibition potential and significant transfiguration of hematological, enzymological, and protein parameters as safe nanomedicine, but ZnONPs were found to be 58, 69, 29 and 34, 51, 70% more active than AgNPs with 4-day and 15-day treatment, respectively. Therefore, the onset of ROX and antioxidant arena favors beneficial cellular drifting of NPs.