Immunostimulatory activities of specific bacterial secondary metabolite ofAnoxybacillus flavithermusstrain SX-4 on carp,Cyprinus carpio

Abstract

Aims: To determine the capacity of secondary metabolite of strain SX‐4, to enhance the nonspecific immunity and survival of carp (Cyprinus carpio), and to identify the constituents that are responsible. Methods and Results: A thermophilic strain SX‐4 that is able to produce immunostimulatory metabolite was isolated from sludge sample of hot spring and identified by comparison with 16S rRNA sequences (99% of homology) as Anoxybacillus flavithermus. Bioactivity‐guided fractionation of methanol extract from its cell‐free culture, one bacterial peptide with the capacity of improving the nonspecific immune responses and disease resistance (relative per cent survival = 66·67%) was obtained and the compound was characterized as cyclo‐(L‐Pro‐Gly) by IR, ESI‐MS, 1H NMR and 13C NMR spectroscopic analyses. After intraperitoneal administration of this peptide, selected innate immune parameters including phagocytic activity, superoxide anion production, serum lysozyme activity and serum SOD activity, along with immune‐related genes expression (i.e. interleukin‐1β and inducible nitric oxide synthase), in the blood were found to be significantly increased. Conclusions: The bacterial peptide cyclo‐(L‐Pro‐Gly) significantly enhances nonspecific immunity and survival of carp. Significance and Impact of the Study: There is a possibility of using cyclo‐(L‐Pro‐Gly) as a better natural immunostimulant, which could have a promising role in aquaculture to prevent diseases and disease outbreaks.

Role of Bacillus licheniformis VS16-Derived Biosurfactant in Mediating Immune Responses in Carp Rohu and its Application to the Food Industry

“…Recently, bacterial secondary metabolites have received greater attention for disease control in fish aquaculture. Liu et al (2011) demonstrated that secondary metabolite cyclo-( L -Pro-Gly), isolated from Anoxybacillus flavithermus SX-4 could enhance non-specific immunity and disease resistance in carp ( Cyprinus carpio ). Isolated secondary metabolites from the soil isolate B. simplex increased cytokine responses and disease resistance against Aeromonas hydrophila challenge in C. carpio (Wang et al, 2011).…”

Use of bacterial subcellular components as immunostimulants in fish aquaculture

“…Liu et al . () determined the capacity of the secondary metabolite cyclo‐( l ‐Pro‐Gly), isolated from Anoxybacillus flavithermus SX‐4, to enhance the nonspecific immunity and disease resistance of carp ( C. carpio ). After intraperitoneal administration of this compound, selected innate immune parameters including superoxide anion production, phagocytic activity and serum lysozyme activity, along with immune‐related gene expression (i.e.…”

Lysozyme of Cyprinidae in Different Climatic Zones

“…У карпа и белого амура зарегистрирована очень низкая активность фермента: от следовых величин до 1,75 мкг/мл (Yang et al, 2008;Ardo et al, 2010;Liu et al, 2011;Weifen et al, 2012). Относительно низкую лизоцимную активность -3,3-13 мкг/млпроявляют сыворотки тропических карповых L. rohita и Puntius sarana (Swain et al, 2007;Dash et al, 2011;Behera, Swain, 2012;Das et al, 2012).…”