Alginate oligosaccharide/polysaccharide and lactic acid bacteria (Lactobacillus bulgaricus FNCC–0041 & Streptococcus thermophilus FNCC–0040) as immunostimulants against pathogenic Vibrio spp. using Artemia bio model

Abstract

Alginate polysaccharide/oligosaccharide (APS/AOS) has been proven as a good immunostimulant. FNCC–0041 & FNCC–0040 are lactic acid bacteria (LAB) producing exopolysaccharides. Vibrio bacteria are pathogenic for aquatic cultivans. This study determines the performance of APS/AOS in combination with LAB as immunostimulants. These were conducted in Artemia challenge test assay against three species of Vibrio spp., namely Vibrio parahaemolyticus (Vp), V. harveyi (Vh), and V. vulnificus (Vv). The treatments were prepared by Factorial Design with two factors (APS/AOS doses and Vibrio spp.) and replicated three times. The APS/AOS concentration was 0, 300, 600, 900 ppm. There were 8 levels of vibrio challenges, namely non-Vibrio, Vp, Vh, Vv, Vp-Vh, Vh-Vp, Vv-Vp, and Vp-Vh-Vv. LAB and APS/AOS were fermented with seawater encapsulated by newly hatched Artemia’s nauplii for one hour. Ten nauplii were taken out and challenged with 108 cells/mL Vibrio. Its survival rate (SR) was counted every six hours until reached 100% mortality. Results show that SR of all nauplii Artemia bio encapsulated treatments was higher than control (p<0.05). The best survival rate was reached from 400 ppm AOS. It has appeared that there is a synergically positive effect among the bio encapsulated AOS and LAB to accelerate the Artemia’s immune system.