The present survey has been conducted to understand the efficaciousness of sugar cane bagasse to bring forth bacterial biofilm in H2O. The survey period was 90 yearss. Entire Plate count ( TPC ) in H2O and substrate was estimated on alimentary agar at room temperature by spread home base method. The TPC in H2O was the highest ( 2.10 x 104 ml-1 ) after 45 yearss. The mean TPC of bacteriums on bagasse varied from 140.0 ( 15d ) to 30.25 ( 90d ) x104·g-1. The present survey demonstrates that the sugar cane bagasse can bring forth more bacteriums in H2O thereby the fish can efficaciously use biofilm grown on sugar cane bagasse and proviso of a substrate reduces the demand for unreal provender.
Cardinal words: Entire Plate Count, Sugarcane bagasse, Microbial biofilm
Introduction
About all submersed surfaces are covered with thin microbic biofilms. These biofilms are present in most marine Waterss including polar ( Ford et al. , 1989 ; Maki et al. , 1990 ) , temperate, ( Berk et al. , 1981 ) and tropical ecosystems ( Hofmann et al. , 1978 ) every bit good as fresh water environments ( Lock, 1993 ) . Biofilms signifier when bacterium attach to surfaces. Their subsequent generation and production of exopolymers forms a thin bed of organic affair that works to pin down foods from the H2O column and provides protection for the micro-organism life within the biofilm ( Van Loosdrecht et al. , 1990 ) . Biofilms can play an of import function in interceding colony and metabolism of invertebrate larvae ( Kirchman and Mitchell, 1981 ; 1983 ; Kirchman et al. , 1982a ; 1982b ; Maki and Mitchell, 1985 ; 1986 ; Maki et al. , 1988 ; 1989 ; 1990 ; 1992 ; 1994 ; Mitchell, 1984 ; Mitchell and Kirchman, 1984 ; Mitchell and Maki, 1988 ; Rodriguez et al. , 1995 ) . Development of feasible low-priced engineerings and their application to current agriculture patterns would assist in heightening aquaculture production. Substrate based aquaculture is one such engineering that has generated a batch of involvement in recent old ages ( Wahab et al. 1999, Tidwell et Al. 2000, Azim et Al. 2001, Keshavanath et Al. 2001 ) . By supplying organic affair and suited substrates, heterotrophic nutrient production can be increased several creases which in bend would back up fish production. Substrates provide the site for epiphytic microbic production, accordingly eaten by fish-food beings and fish. Fish crop micro-organisms straight in important measures, either from microbic biofilm on debris or from of course happening flocks in H2O column ( Schroeder 1978 ) . Provision of substrate would therefore, be utile for the growing of microbic biofilm. Apart from organizing nutrient for fish, biofilm improves H2O quality by take downing ammonia concentration ( Langis et al. 1998, Ramesh et Al. 1999 ) , this implies the utility of substrates in bettering H2O quality in civilization systems, by take downing ammonia concentration. Hence, in the present survey effort has been made to measure the efficaciousness of sugar cane bagasse to bring forth biofilm in H2O.
MATERIALS AND METHODS
The experiment was conducted over a period of 90 yearss in two 25 M2s ( 5 x 5 ten 1 m ) cement armored combat vehicles with 15cm dirt base. The armored combat vehicles were ab initio received 0.25 kilograms of speedy calcium hydroxide and 2.5 kilogram of domestic fowl manure. Water was filled to the armored combat vehicles from a perennial well and a deepness of 90 ± 2 centimeter was maintained throughout the experimental period. Subsequently, domestic fowl manure was applied at 0.3 kilograms per armored combat vehicle every 15 yearss. Sugarcane bagasse, procured locally, was sun dried and packages were made utilizing nylon rope ; they were introduced into the armored combat vehicles indiscriminately at the rate of 5 kilograms each, by suspending the packages at regular distances from bamboo poles kept across the armored combat vehicles. After 45 yearss, one time once more 1.25 kilogram of the substrate was supplemented to each of the designated armored combat vehicles. Entire Plate count ( TPC ) in H2O was estimated on alimentary agar at room temperature by spread home base method. TPC on substrate was enumerated harmonizing to Anwar et Al. ( 1992 ) . A known measure of substrate was collected and rinsed three times to take slackly adherent cells. Then it was resuspended in phosphate-buffered saline and vortexed for three proceedingss to free the biofilm cells and TPC of the suspension estimated as figure per gm of substrate.
RESULTS AND DISCUSSION
Microbial communities play cardinal functions in the Earth ‘s biogeochemical rhythms. A biofilm is an gathering of microbic cells that is irreversibly associated ( non removed by soft rinsing ) with a surface and enclosed in a matrix of chiefly polysaccharide stuff. Non-cellular stuffs such as mineral crystals, corrosion atoms, clay or silt atoms depending on the environment in which the biofilm has developed, may besides be found in the biofilm matrix. The solid-liquid interface between a surface and an aqueous medium ( e.g. , H2O ) provides an ideal environment for the fond regard and growing of micro-organisms. The solid surface may hold several features that are of import in the attachment procedure. Characklis et Al. ( 1990 ) noted that the extent of microbic colonisation appears to increase as the surface raggedness additions. Other features of the aqueous medium, such as pH, alimentary degrees, ionic strength, and temperature, may play a function in the rate of microbic fond regard to a substrate. Several surveies have shown a seasonal consequence on bacterial fond regard and biofilm formation in different aqueous systems ( Mitchell, 1984 ; Mitchell and Maki, 1988 ) . This consequence may be due to H2O temperature or to other immeasurable, seasonally affected parametric quantities. Fletcher ( 1988, 1988a ) found that an addition in the concentration of several cations ( Na, Ca, La, ferrous Fe ) affected the fond regard of Pseudomonas fluorescens to glaze surfaces. Cowan et Al. ( 1991 ) showed in a research lab survey that an addition in alimentary concentration correlated with an addition in the figure of affiliated bacterial cells. A material surface exposed in an aqueous medium will necessarily and about instantly become conditioned or coated by polymers from that medium, and the ensuing chemical alteration will impact the rate and extent of microbic fond regard. Loeb and Neihof ( 1975 ) were the first to describe the formation of these conditioning movies on surfaces exposed in H2O. These research workers found that movies were organic in nature, formed within proceedingss of exposure, and continued to turn for several hours. Furthermore, belongingss of the cell surface, specifically the presence of fimbriae, scourge, and surface-associated polyoses or proteins, besides are of import and may perchance supply a competitory advantage for one being where a assorted community is involved.
In the present survey, the TPC in H2O showed a gradual addition from 15days ( vitamin D ) to 90d and was highest ( 2.10 x 104 ml-1 ) after 45 yearss. The TPC of bacteriums on bagasse showed a diminishing tendency from 15d to 90d ( 140.0 to 30.25 x104·g-1 ) . More inside informations are given in table1. Alimentary enrichment of H2O is known to increase both the thickness and cellular denseness of bacterial biofilm ( Radhakrishnan and Sugumaran, 2010 ) . The higher bacterial denseness in H2O from bagasse based armored combat vehicles is due to the organic affair contributed by manure every bit good as the foods present in bagasse ( Radhakrishnan and Sugumaran, 2010 ) . In add-on, bacteriums in the biofilm could hold added free cells to the H2O. This might be the ground for the uninterrupted addition of bacteriums in H2O and lessening in the settlement in the sugar cane bagasse for a long clip. Furthermore, the foods present in the bagasse cause an initial addition. The present consequence demonstrates that the sugar cane bagasse can bring forth more bacteriums in H2O thereby the fish can efficaciously use biofilm grown on sugar cane bagasse and proviso of a substrate reduces the demand for unreal provender. Since biodegradable wastes have high C: N ratio and seaport higher periphytic biomass, they are better suited as substrates ( Azim et al. , 2001 ) . Use of cheaper substrates like sugar cane bagasse can greatly better economic viability of aquaculture.
