DIFFERENT CULTURE MODES ON QUALITY OF ERIOCHEIR SINENSIS

In order to explore the effects of different culture modes on the quality of Eriocheir sinensis, commonly known as Chinese mitten crabs, specimens (referred to as pond crab and paddy crab) were collected from the Yangcheng Lake area and the Panjin area, respectively. Their tissue coefficient, total availability, free amino acid composition, carotenoid content, antioxidant enzyme activity, and DNA methylation level were compared. The results showed that the gonadal index (GSI), meat yield (MY), and total availability (TEY) of paddy crab exceeded those of pond crab. MY and TEY exhibited significant differences between the two crab samples (P<0.01). The pond crab displayed higher levels of sweet and umami amino acids, while the paddy crab exhibited a higher total amino acid content. Carotenoids levels in the hepatopancreas and ovaries of pond crabs were notably higher than those in paddy crab, with significant variations observed in female crab tissues (P<0.01). Levels of malondialdehyde (MDA) in the hepatopancreas of male crab and muscle tissues of female crabs under both culture methods differed significantly (P<0.01), as did superoxide dismutase (SOD) activity (P<0.05). Catalase activity exhibited significant differences in various tissues (P>0.05), while catalase (CAT) activity did not. In addition, DNA methylation levels in different E. sinensis tissues varied significantly under the two culture modes. The results indicated that different farming patterns combined with climatic factors had significant effects on the total availability, free amino acid content, and DNA methylation level of E. sinensis. The significant differences in DNA methylation levels resulted in differential expression of gene expression, indicating that different farming patterns contribute to variations in crab quality.