The effectiveness of mangrove endophytic fungal metabolite Penicillium sp. KTR58 on the growth and immune response of Pacific white shrimp Litopenaeus vannamei

Abstract

Mangrove endophytic fungi have the potential to act as immunostimulants for shrimp and antibacterial agents against V. parahaemolyticus, including Penicillium sp. KTR58. This study aimed to determine the effect of adding Penicillium sp. KTR58 metabolites on the growth and immune response of Pacific white shrimp. The research consisted of in vitro and in vivo tests. The shrimp were maintained for 30 days using a completely randomized design with 4 treatments, namely K (0), P10 (10), P20 (20), and P30 (30 ml/kg feed), each with 3 replicates. In vitro test showed that the highest inhibition zone at 30 μL/disc treatment and thin-layer chromatography indicated the presence of steroid, flavonoid, terpenoid, saponin, coumarin, and alkaloid compounds. The compounds showing antibacterial activity from the bioautography test were suspected to be coumarins, flavonoids, alkaloids, saponins, and steroids. Treatment P20 showed the best growth performance and immune response, with a final weight of 8.87 ± 0.16 g, final biomass of 123.79 ± 8.1 g, a specific growth rate of 3.96 ± 0.18 %/day, and a feed conversion ratio of 1.45 ± 0.05, these values were significantly different from the control (P<0.01). The total haemocyte count, phagocytosis activity, respiratory burst, and phenoloxidase values were 9.33×10⁶ ± 0.31×10⁶cells/ml, 49.73 ± 1.89%, 0.31 ± 0.01, 0.29 ± 0.002 respectively, and were significantly different from the control (P<0.05). Based on these results, the optimal dose of Penicillium sp. KTR58 metabolite addition in Pacific white shrimp feed is 20 ml/kg.

Keywords: acute hepatopancreatic necrosis disease (AHPND), Penicillium sp. KTR58, shrimp immunostimulant, Vibrio parahaemolyticus