Speciation transformation of arsenic in abalone viscera hydrolysate fraction: In vitro digestion and in vivo metabolism

Speciation transformation of arsenic in the abalone viscera hydrolysate fraction (AVHF) was evaluated using in vitro and in vivo methods to determine its safety given that AVHF is rich in arsenic. The dimethylarsinic acid (DMA) proportion and some free amino acid contents increased, whereas arsenobetaine (AB) proportion decreased when AVHF was digested by pepsin. However, molecular weight distribution was unchanged, and no obvious changes were found in the intestinal medium. In the single-dose experiment, the AB concentration on the mouse plasma rapidly increased, which reached up to 12.53 ng/mL in 2 h after the administration of AVHF (10 g/kg body weight) and reduced to half of the maximum at 8 h after administration. Furthermore, alanine (Ala) content in the urine of mice increased at 8 h after AVHF administration, suggesting that Ala might be chelated with arsenic and could not be absorbed well. Long-term experiments showed that AB was not accumulated in mice tissue/organ. However, some AB could be converted into DMA, which was mainly accumulated in mice hair. The in vivo experiments also suggested that the AVHF is safe as health food.