Abstract

Aquaculture is vital for global food security and economic development, with shrimp farming being a key contributor to seafood production. Shrimp aquaculture has expanded significantly in the Philippines, including in General Santos City. However, the intensification of shrimp farming has increased vulnerability to disease outbreaks, such as Acute Hepatopancreatic Necrosis Disease (AHPND), which causes severe economic losses. While farmers commonly use antibiotics for disease control, their misuse and overuse contribute to antimicrobial resistance (AMR), posing serious health and environmental risks. Natural alternatives like probiotics have emerged as sustainable solutions to address this. Marine-derived probiotics, particularly lactic acid bacteria (LAB), promise to improve shrimp health, enhance immunity, and resist pathogens. This study focuses on identifying LAB with probiotic potential isolated from the gut of Whiteleg shrimp (Litopenaeus vannamei) farmed in General Santos City, Philippines. Specifically, this study aims to: (1) isolate LAB using selective media, (2) to characterize the bacterial isolates through morphological and biochemical assays, (3) assess probiotic potential through antagonistic activity against Vibrio parahaemolyticus, pH and bile salt tolerance, and hemolytic activity, and (4) identify the most effective isolate using 16S rRNA gene sequencing. By identifying LAB with strong probiotic properties, the anticipated result of the study will further provide information on the existing pool of knowledge on marine-derived probiotics for sustainable shrimp farming practices and support global efforts to reduce AMR. Though limited to in vitro experiments, the study offers valuable groundwork for future in vivo applications and probiotic development in aquaculture.