Screening and evaluation of probiotics as a biocontrol agent against pathogenic Vibrios in marine aquaculture.
OBJECTIVE
The present work aims at finding potential probionts from marine sources as a biocontrol agent against pathogenic Vibrio species in shrimp larval culture.


RESULTS
A total of 109 bacterial strains were isolated from seawater, sediment and marine fish-gut samples, and were screened for their antagonistic activity against Vibrio species. Three strains (Q, Q1 and M) isolated from the marine sediment were found antagonistic against Vibrio strains. Based on 16S ribosomal DNA gene sequence analysis, the strain Q was identified as Paenibacillus spp. (EF012164); Q1 as Bacillus cereus (DQ915582); and the M as Paenibacillus polymyxa (DQ915580). Further, the two bacterial species, Paenibacillus spp. and B. cereus were challenged separately at two different concentrations of 10(4) and 10(5) CFU ml(-1) for probiotic activity in the postlarvae of Penaeus monodon against pathogenic Vibrio harveyi and Vibrio spp.


CONCLUSIONS
The present study identified the probiotic activity of Paenibacillus spp., B. cereus and Pa. polymyxa against the pathogenic Vibrios in the postlarvae of P. monodon.


CONCLUSIONS
In vivo study reveals that the marine bacterial species can be used as probionts against pathogenic Vibrios in shrimp larval culture practices.
Ravi
A V
AV
Department of Biotechnology, Alagappa University, Karaikudi, Tamil Nadu, India. aveeraravi@rediffmail.com
Musthafa
K S
KS
Jegathammbal
G
G
Kathiresan
K
K
Pandian
S K
SK
D000818:Animals; D000898:Antibiosis; D017756:Aquaculture; D001409:Bacillus cereus / Q000145:classification / Q000235:genetics / Q000254:growth & development*; D001419:Bacteria / Q000145:classification / Q000235:genetics / Q000254:growth & development*; D007814:Larva / Q000382:microbiology; D008969:Molecular Sequence Data; D033561:Penaeidae / Q000254:growth & development / Q000382:microbiology*; D010572:Pest Control, Biological / Q000379:methods; D019936:Probiotics; D012623:Seawater; D017422:Sequence Analysis, DNA; D014733:Vibrio / Q000145:classification / Q000235:genetics / Q000254:growth & development* / Q000472:pathogenicity; D041261:Vibrio vulnificus / Q000254:growth & development / Q000472:pathogenicity