Biological toxicity of fresh and rotten algae on freshwater fish: LC50, organ damage and antioxidant response was written by Gu, Peng;Li, Qi;Zhang, Weizhen;Gao, Yang;Sun, Ke;Zhou, Liang;Zheng, Zheng. And the article was included in Journal of Hazardous Materials in 2021.Application In Synthesis of 1,3-Dicyclohexylurea This article mentions the following:
In recent decades, harmful algal blooms (HABs) induced by eutrophication have caused organisms in freshwater ecosystems to become surrounded by toxic cells and dissolved toxins. In this study, the toxic effects of fresh algae solution (FAS) and rotten algae solution (RAS) were investigated. The results showed that the composition of RAS was predominantly organic acids, ketones, polypeptides, esters, phenols, amino acids and intermediate metabolic products. The safety concentrations (SCs) of FAS to Carassius auratus, Ctenopharyngodon idellus and Hypophthalmichthys molitrix were 1.92 x 1010 cells/L, 1.58 x 1011 cells/L and 1.30 x 1011 cells/L, resp. The SCs of the RAS were significantly lower than those of the FAS (p < 0.05), with the values of 1.25 x 109 cells/L, 8.8 x 109 cells/L and 9.7 x 109 cells/L, for each species, resp. The toxic algae solutions caused congestion inside the gills, intestinal lesions and high infection rates in the tested fish. FAS and RAS exposure also activated the antioxidant defense system and changed the intestinal microbial structure, resulting in the damage to the microbial balance in the body, and eventually the death of the fish. By studying the acute toxicity to fish, the harm of HABs to aquatic organisms can be predicted. In the experiment, the researchers used many compounds, for example, 1,3-Dicyclohexylurea (cas: 2387-23-7Application In Synthesis of 1,3-Dicyclohexylurea).
1,3-Dicyclohexylurea (cas: 2387-23-7) belongs to amides. Compared to amines, amides are very weak bases and do not have clearly defined acid–base properties in water. On the other hand, amides are much stronger bases than esters, aldehydes, and ketones. Ionic, or saltlike, amides are strongly alkaline compounds ordinarily made by treating ammonia, an amine, or a covalent amide with a reactive metal such as sodium.Application In Synthesis of 1,3-Dicyclohexylurea
Referemce:
Amide – Wikipedia,
Amide – an overview | ScienceDirect Topics