Figure 2.

Intestinal histomorphology and enzyme activities in H. leucospilota under graded dietary gallic acid (GA) supplementation. (A) Representative hematoxylin and eosin (H&E)‐stained intestinal sections from sea cucumbers in the control (Con) and GA‐supplemented groups (GA1–GA5) after the 75‐day feeding trial. Images were observed and captured under 20× magnification. Black scale bars represent 50 μm. (B) Antioxidant‐related indicators in intestinal tissue, including superoxide dismutase (SOD), catalase (CAT), and malondialdehyde (MDA). SOD and CAT activities are expressed as U mg⁻¹ protein, and MDA content is expressed as nmol mg⁻¹. (C) Digestive enzyme activities in intestinal tissue, including α‐amylase, lipase, pepsin, and cellulase, expressed as U mg⁻¹ protein. For B and C, bars show mean ± SD. Different letters above bars indicate significant differences among treatments (p < 0.05; one‐way ANOVA followed by Tukey’s multiple‐comparison test).