Study of Ligmed-A, an antidiarrheal drug based on lignin, on rat small intestine enzyme activity and morphometry.

This study aimed to determine the potential toxic effect of 4-day oral treatment with a lignin-based formulation on the enzymatic activity and morphology of the small intestine of rat. Ligmed-A is collected from sugarcane and is used to treat diarrhea in weaning pigs. The compound is about 90% lignin, an insoluble polyphenolic constituent of plants and a component of dietary fiber. The duodenal, jejunal and ileal mucosa of control rats and those receiving 2 g/kg Ligmed-A showed similar protein contents of about 100 mg/g. The sucrase and alkaline phosphatase activities of the three intestinal segments were unaltered after administration of the compound. Nonhistological alterations were observed after treatment. Our results, together with those of previous studies which found no toxicological effects, indicate that Ligmed-A could provide a potent antidiarrheal treatment in the veterinary area. However, further studies are required to examine its use in humans.     

Effects of Echerichia coli lipopolysaccharides and dissolved ammonia on immune response in southern white shrimp Litopenaeus schmitti

The success of penaeid shrimp aquaculture has been limited by endemic and epidemic infectious diseases around the world and shrimp defense mechanisms are a priority for control, prevention, and diagnosis. The lethal dose (LD₅₀) of Escherichia coli lipopolysaccharides was calculated and pathogen injection and dissolved ammonia concentration on immune response were evaluated in southern white shrimp Litopenaeus schmitti. The lethal dose of lipopolysacharides was 3.78 mg kg^− 1 body weight. Injection caused changes in phenoloxidase activity in plasma and nitric oxide and total haemocyte counts within the first 24 h. High concentration of dissolved ammonia caused a decrease in haemocytes by 66% within the first 72 h, when compared to the control. Hemagglutination in plasma was not affected by injection or high concentrations of dissolved ammonia. The results showed that white shrimp recognized the lipopolysacharides and responded to this microbial elicitor, as indicated by a variety of immunological indicators and that increased dissolved ammonia affected the number of circulating haemocytes.