Diversity and Density of Coliform Bacteria in River Tunga at Shivamogga City, Karnataka, India
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Int.J.Curr.Microbiol.App.Sci (2015) 4(7): 624-631 ISSN: 2319-7706 Volume 4 Number 7 (2015) pp. 624-631 http://www.ijcmas.com Original Research Article Diversity and Density of Coliform Bacteria in River Tunga at Shivamogga city, Karnataka, India S. Prathibha and V.N.Murulidhar* 1Department of Botany, JSS Degree College for Women (Autonomous), Mysore-570025, Karnataka, India 2Department of Botany, Government First Grade College, Sira-572103, Tumkur District, Karnataka, India *Corresponding author A B S T R A C T Water resources are being polluted due to increasing urbanization, modern practices in agriculture and other human activities. The link between human health K e y w o r d s and environmental pollution is of significant dimension. Studies were conducted with an objective of assessing the coliforms density and dynamics in river Coliform Tungawater. River is polluted with domestic and agriculture wastes of Shivamogga bacteria, city. Water samples were collected from four designated sampling stations of the Water, river. Results revealed that, all the samples from the selected stations contained River, coliforms bacteria above the safe limits for drinking water standards. Thus river Pollution water is unsatisfactory as judged by mean MPN counts of indicator bacteria i.e., total coliforms 2.22 x 107/100 ml. Seasonal variations in coliforms density were recorded with maximum density in summer and monsoon seasons and minimum density in winter seasons. Introduction Water contamination by various routes and directly to detect the presence of all the agents are liable to cause clinically signified different kinds of water borne pathogens, outbreaks of intestinal infections in both any of which may be present only animals and man. The demonstration of intermittently. Thus, we rely on tests that pathogenic bacteria, would obviously reflect the presence of commensal bacteria constitute the most direct proof of a of intestinal origin such as those of the hazardous impurity; but these pathogens, if coliform group, which are more numerous, present are so scanty that the technical more easily tested and are the most reliable difficulty of their isolation makes the test indicators of fecal pollution (Senior, 1989). impractical for ordinary purposes and they Each person discharges 100 to 400 billion are very sensitive even to a slight change of coliform organisms/day, in addition to other environmental factors and difficult to kinds of bacteria. These coliforms do not isolate. Hence, it is impractical to attempt themselves constitute a hazard since, they 624 Int.J.Curr.Microbiol.App.Sci (2015) 4(7): 624-631 are harmless to man and are in fact useful in be indicators for potential pathogens destroying organic matter in biological responsible for various waterborne diseases waste treatment processes. But they indicate (Hunter et al., 2004) or be pathogens that faecal matter has entered and that the themselves, such as certain strains of E. coli. water is therefore, liable to contamination In the present experiment we tested water with more dangerous organisms (Senior, pools in 96 samples at a stretch of 15 km of 1989). Presence of coliform organisms is Tunga River for abundance and species thus taken to indicate possible presence of richness of coliform and other pathogenic organisms. environmental bacteria. We hypothesized that river with more human or animal Coliform monitoring being rapid, anthropogenic activities or watershed with inexpensive easy to perform, proved agricultural or sewage runoff would have effective (Leclerc et al., 2000). Coliform higher bacterial abundance and species was the term first used in 1880 s to describe richness. rod-shaped bacteria. Coliform group of bacteria is functionally-related groups Material and Methods belong to a single taxonomic family Enterobacteriaceae and comprises many The present study area covered a stretch of genera and species. The term coliform 15 km of the river Tunga near Shivamogga organisms refers to gram-negative, rod- city. Ninety six water samples from Tunga shaped bacteria capable of grow in presence river were collected during April 2010- of bile salts or other surface-active agents March 2012 (24 months) from all the four with similar growth-inhibiting properties designated stations and were analysed for and able to ferment lactose at 35 ºC 37 ºC the levels (MPNs) of generally accepted with the production of acid, gas and faecal pollution indicators i.e., total aldehyde within 24-48 hours (Clesceri et al., coliforms (TC). Seasonal variations were 1998). They are also oxidase-negative and examined among these indicators during non-spore-forming and display b- April 2010 to March 2012 as well as the galactosidase activity (Arora, 2003). species composition for each group of Traditionally coliform bacteria were indicators. The pollution range, maxima, regarded as belonging to the genera minima, standard deviation of the above Escherichia, Citrobacter, Enterobacter and parameter has been given along with the Klebsiella. MacConkey (1909) defined 128 detailed discussion of the parameter coliform types and this number was including ANOVA results. Presumptive increased to 256 by a system developed by coliform count: Single and Double strength Bergey and Deehan (1908). However, as MacConkey s broth medium (Hi-media, defined by modern taxonomic methods, the Ltd.) was prepared by dissolving 4 g and 8 g group is heterogenous consisting of as many of MCB in 100 ml of distilled waters as 32 genera (Leclerc et al., 2001). Some of separately. Measured amounts were these can be found in both faeces and the sterilized in test tubes containing a environment (nutrient-rich waters, soil, Durham s tube for indicating gas decaying plant material) as well as in production. With sterile graduated pipettes drinking water with relatively high or with adjustable micropipettes that can concentration of nutrients and may multiply. hold sterilized microtips, the following Eg. Serratia fonticola, Rahnella aquatilis, amounts of the sampled waters were added. Buttiauxella agrestis. Coliform bacteria can 625 Int.J.Curr.Microbiol.App.Sci (2015) 4(7): 624-631 a. Five 10 ml quantities each to DS between station and season is also (Double Strength) medium. statistically non-significant as all the b. Five 1 ml quantities each to 10 ml SS obtained values failed to reach the (Single strength) medium. significant level. Even though, we find c. Five 0.1 ml quantities each to 10 ml comparative differences among means, these SS medium. mean differences are statistically insignificant, as there were high individual Tubes that show acid and sufficient gas to variations in the data, which is evident from fill the apex covering the concavity of the respective standard deviation (SD) Durham s tube at 24 hours were considered values (Table 2). Presence of coliform to be presumptive positive, as a result of the organisms in water has been attributed to growth of coliform Bacilli after incubation influxes of allochthonous bacteria from at 37 ºC. Incubation was sustained from the waste discharges and surface water drainage. next session; tubes showing presumptive Total coliform levels were always higher positive at 48 hours of incubation were than faecal coliform levels, which is not accredited to the existing numbers in the surprising since total coliforms can originate concerned station. Sample dilutions were from non-faecal sources also such as plants read separately and the positives in A, B and and soils (Geldreich, 1974). The above C were serially collated in probability tables findings and opinions also were to obtain presumptive coliform Bacilli in corroborated by Goyal et al. (1977). 100 ml of the sampled station. Tubes showing gas production at 37 ºC for 48 In the present study, high coliform load has hours were confirmed by plating in been registered during the entire course of MacConkey agar plates (MCA) and study. The MPN of coliform organisms examined for typical colonies. fluctuated from 17 x 101 to 16 x 108 / 100 ml. The higher values of MPN for coliforms Results and Discussion were recorded at TS3 and TS4, mainly attributed to the domestic sewage and In the present investigation two-way municipal wastes. Though, the values ANOVA was employed taking test stations remain statistically significant, due to high (TS1, TS2, TS3 and TS4) as first independent individual variations in the data, as per variable and seasons (summer, rainy and values in the current study the distribution of winter) as second independent variable total coliforms MPN was found bimodal against all parameters considered as with summer and monsoon maxima. Higher dependent variables. The first variable coliform levels occurring during summer (stations) varied at 4-levels, 2nd variable months suggest survival and high influx of (seasons) varied at 3-levels to make 4x3 the coliforms and also increased nutrient design. This will yield different between the influx from decomposition of summer stations, difference between season s productivity because of high temperature interaction between stations and seasons and watershed drainage may also contribute (Lateef et al., 2005). The maximum, to March-April increase in numbers of both minimum and averages of two years in the the years. In addition, heavy usage of the total Coliforms are represented in table 1. In river was found during summer for bathing, the current study, no significant difference washing and such other anthropogenic was noticed between stations and seasons, in activities, that also