Effects of phyllanthus amarus extract on digestive enzymes and stress resistance of striped catfish (Pangasianodon hypophthalmus) at the fingerling stage

Abstract

This research was carried out to determine the effects of Phyllanthus amarus extract on selected enzymes and stress resistance of striped catfish fingerling stage (Pangasianodon hypophthalmus). The study included two experiments (i) the experiment 1, fish was fed diets without the extract (control) and extract 0.5% Phyllanthus amarus supplementation in 42 days. The intestine and stomach samples was collected at day 0th and 42nd for analyzing digestive enzymes activities. The results indicated that pepsin, trypsin, and chymotrypsin activities in the stomach and intestine varied significantly (p<0.05). After 42 days, the enzyme activities of the fish in control and supplementary Phyllanthus amarus treatment such aspepsin presented 0.13 and 0.29 mU/mL/mg protein; trypsin increased from 1.06 to 2.6 mU/mL/mg protein; chymotrypsin were 43.23 and 64.46 mU/mL/mg protein respectively. (ii) the fish of the experiment 1 were used for challenged with temperatures as 27°C, 31°C and 35°C in 14 days. The sampling period was implemented on day which reached the target temperature, day 7th, and day 14th for analyzing stress indicators and digestive enzyme activities. The results showed that glucose concentration decreased in Phyllanthus amarus treatment, the lowest glucose concentration of fish was found significantly of Phyllanthus amarus (41.70 mg/dL) at 35°C after 7 days. In conclusion, supplementation of 0.5% Phyllanthus amarus reduced glucose concentration and increased the activity of digestive enzymes of striped catfish. The research showed that Phyllanthus amarus had an effective effect on reducing stress and improving digestion of striped catfish.