Bright Singh, I S; Vijayan, K K; Jayaprakash, N S; Alavandi, S V; Somnath Pai, S; Preetha, R; Rajan, J J S; Santiago, T C(Elsevier, October 2, 2005)
[+]
[-]
Abstract:
A Pseudomonas sp PS-102 recovered from Muttukkadu brackish water lagoon, situated south of Chennai, showed significant
activity against a number of shrimp pathogenic vibrios. Out of the 112 isolates of bacterial pathogens comprising Vibrio harveyi, V.
vulnificus, V. parahaemolyticus, V. alginolyticus, V. fluvialis, and Aeromonas spp, 73% were inhibited in vitro by the cell-free culture
supernatant of Pseudomonas sp PS-102 isolate. The organism produced yellowish fluorescent pigment on King's B medium,
hydrolysed starch and protein, and produced 36.4% siderophore units by CAS assay and 32 μM of catechol siderophores as
estimated by Arnow's assay. The PS-102 isolate showed wide ranging environmental tolerance with, temperatures from 25 to 40 °C,
pH from 6 to 8, salinity from 0 to 36 ppt, while the antagonistic activity peaked in cultures grown at 30 °C, pH 8.0 and at 5 ppt saline
conditions. The antagonistic activity of the culture supernatant was evident even at 30% v / v dilution against V. harveyi. The
preliminary studies on the nature of the antibacterial action indicated that the antagonistic principle as heat stable and resistant to
proteolytic, lipolytic and amylolytic enzymes. Pseudomonas sp PS 102 was found to be safe to shrimp when PL-9 stage were
challenged at 107 CFU ml−1 and by intramuscular injection into of ∼5 g sub-adults shrimp at 105 to 108 CFU. Further, its safety in a
mammalian system, tested by its pathogenicity to mice, was also determined and its LD50 to BALB/c mice was found to be 109 CFU.
The results of this study indicated that the organism Pseudomonas sp PS 102 could be employed as a potential probiont in shrimp
and prawn aquaculture systems for management and control of bacterial infections
Bright Singh, I S; Somnath Pai, S; Jayaprakash, N S; Anas, A; Rosamma, Philip; Preetha, R(Inter-Research, December 30, 2005)
[+]
[-]
Abstract:
marine bacterium, Micrococcus MCCB 104, isolated from hatchery water, demonstrated
extracellular antagonistic properties against Vibrio alginolyticus, V. parahaemolyticus, V. vulnificus,
V. fluviallis, V. nereis, V. proteolyticus, V. mediterranei, V. cholerae and Aeromonas sp., bacteria
associated with Macrobrachium rosenbergii larval rearing systems. The isolate inhibited the
growth of V. alginolyticus during co-culture. The antagonistic component of the extracellular product
was heat-stable and insensitive to proteases, lipase, catalase and α-amylase. Micrococcus MCCB 104
was demonstrated to be non-pathogenic to M. rosenbergii larvae
Description:
DISEASES OF AQUATIC ORGANISMS
(Dis Aquat Org)Vol. 68: 39–45, 2005
Rosamma, Philip; Preetha, R; Jayaprakash, N S; Bright Singh, I S(The Society for Applied Microbiology, 2007)
[+]
[-]
Abstract:
Aim: To develop a new medium for enhanced production of biomass of an
aquaculture probiotic Pseudomonas MCCB 103 and its antagonistic phenazine
compound, pyocyanin.
Methods and Results: Carbon and nitrogen sources and growth factors, such as
amino acids and vitamins, were screened initially in a mineral medium for the
biomass and antagonistic compound of Pseudomonas MCCB 103. The selected
ingredients were further optimized using a full-factorial central composite
design of the response surface methodology. The medium optimized as per the
model for biomass contained mannitol (20 g l)1), glycerol (20 g l)1), sodium
chloride (5 g l)1), urea (3Æ3 g l)1) and mineral salts solution (20 ml l)1), and
the one optimized for the antagonistic compound contained mannitol (2 g l)1),
glycerol (20 g l)1), sodium chloride (5Æ1 g l)1), urea (3Æ6 g l)1) and mineral
salts solution (20 ml l)1). Subsequently, the model was validated experimentally
with a biomass increase by 19% and fivefold increase of the antagonistic
compound.
Conclusion: Significant increase in the biomass and antagonistic compound
production could be obtained in the new media.
Significance and Impact of the Study: Media formulation and optimization are
the primary steps involved in bioprocess technology, an attempt not made so
far in the production of aquaculture probiotics.
Bright Singh, I S; Preetha, R; Jayaprakash, N S(Inter-Research, March , 2007)
[+]
[-]
Abstract:
Synechocystis MCCB 114 and 115 were segregated as putative probionts for shrimp
larvae from a collection of 54 cyanobacterial cultures enriched from seawater. On feeding Penaeus
monodon post-larvae with the cyanobacteria, the generic diversity of the intestinal bacterial flora
could be enhanced with substantial reduction or total absence of Vibrio spp. A significant difference
(p < 0.001) in the percent survival of batches of post-larvae fed on the cyanobacterial cultures was
observed and, on repeated challenge with V. harveyi, the relative percent survival of those batches
of larvae fed on Synechocystis MCCB 114 and 115 was significantly higher. The Synechocystis
MCCB 114 and 115 cultures were found to contain high levels of protein (34 to 43%), in addition to
carotenoids