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Studies on water quality and pathogenic bacteria in coastal water Langkawi, Malaysia. Author Details. K.C.A. Jalal. Department of Biotechnology, Kulliyyah of ...
831 J. Environ. Biol. 33, 831-835 (2012) ISSN: 0254- 8704 CODEN: JEBIDP

© 2012 Triveni Enterprises Vikas Nagar, Lucknow, INDIA [email protected] Full paper available on: www.jeb.co.in

Studies on water quality and pathogenic bacteria in coastal water Langkawi, Malaysia Author Details K.C.A. Jalal (Corresponding author)

Department of Biotechnology, Kulliyyah of Science, International Islamic University Malaysia, Bandar Indera Mahkota - 25200, Malaysia e-mail: [email protected]

H.N. Noor Faizul

Department of Biotechnology, Kulliyyah of Science, International Islamic University Malaysia, Bandar Indera Mahkota - 25200, Malaysia

M. Azrul Naim

Department of Biotechnology, Kulliyyah of Science, International Islamic University Malaysia, Bandar Indera Mahkota - 25200, Malaysia

B. Akbar John

Department of Biotechnology, Kulliyyah of Science, International Islamic University Malaysia, Bandar Indera Mahkota - 25200, Malaysia

B.Y. Kamaruzzaman

Department of Biotechnology, Kulliyyah of Science, International Islamic University Malaysia, Bandar Indera Mahkota - 25200, Malaysia

Abstract A study on physico-chemical parameters and pathogenic bacterial community was carried out at the coastal waters of Pulau Tuba island, Langkawi. The physico-chemical parameters such as temperature (27.4328.88oC), dissolved oxygen (3.79-6.49 mg l-1), pH (7.72-8.20), salinity (33.10-33.96 ppt), total dissolved solids (32.27-32.77 g l-1) and specific conductivity (49.83-51.63 mS cm-1) were observed. Station 3 and station 4 showed highest amount of nitrates (26.93 and 14.61 µg at N l-1) than station 1 (2.04 µg at N l-1) and station 2 (4.18 µg at N l-1). The highest concentration (12.4± µg l-1) of chlorophyll a was observed in station 4 in October 2005. High phosphorus content (561Pg P l-1) was found in the station 2. Thirteen bacterial isolates were successfully identified using API 20E system. The highest amount of bacteria was observed at Station 4 (3400 CFU ml-1) and the lowest number was at Station 2 (890 CFU ml-1). Out of identified 13 Gram-negative bacterial isolates dominant species were Aeromonas hydrophila, Klebsiella oxytoca, Pseudomonas baumannii, Vibrio vulnificus, Proteus mirabilis, Providencia alcalifaciens and Serratia liquefaciens. Apart from this, oil biodegrading Pseudomonas putida were also identified. The study reveals the existing status of water quality is still conducive and the reasonably diverse with Gram-negative bacteria along the Pulau Tuba Langkawi.

Publication Data Paper received: 01 May 2010 Revised received: 02 December 2010 Accepted: 06 August 2011

Key words Coastal waters, Pathogenic bacteria, Bacterial community, Colony forming unit

Introduction The coastal area is one of the vital parts of the marine environment which is directly influenced by human activities that has a major impact on aquatic ecosystems and their biological resources. Coastal waters in general, and, in particular, shelf areas, semi-enclosed and enclosed seas, embayments, estuaries, and wetland areas, often benefit from flows of nutrients from the land and/or also from ocean upwelling which brings nutrient-rich water

to the surface (Ruyitno et al., 2001). They thus tend to have particularly high and low biological productivity due to fluctuation of physico-chemical parameters (Lindstrom, 2001). To withstand adverse environmental conditions, microorganisms have developed a huge range of metabolic abilities leading to their enormous diversity. Bacterias are considered to be the main component in establishing heterotrophic link between particles and dissolved organic matter in open ocean and in coastal ecosystems through influencing nutrient Journal of Environmental Biology ‹July 2012‹

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cycles (Muswerry, 2003). Without a doubt, they play a major role in the aquatic biogeochemical cycles (Rajendran et al., 1995). Environmental parameters not only influence the size and composition of bacterial communities, but also direct their activity and leads to viability of these bacteria (Jalal et al., 2010). Hence, it is very essential to study the distribution of bacteria in any particular environment with respect to the environmental conditions like physico-chemical parameters in order to understand the dynamic of bacterial communities (Helbling et al., 1995; Chau, 2006). Microbial ecology has three imperative goals with respect to understanding the roles of microorganism in their natural habitats: (1) to define population dynamics in the communities, (2) to define physico-chemical characteristics of the microenvironments and (3) to understand the metabolic process carried out by microorganism at specific habitats. In order to accomplished these goals, it is essential to determine the roles of each individual organism in the context of functioning communities in the environment (Chui and Choon, 2008). However, most of the studies in Malaysia were restricted to east coast, Port Dickson and the Straits of Malacca, Malaysia (Japar Sidik et al., 2003). Many natural and anthropogenic fluxes that determine the ecological state of the coastal water Langkawi have been recognized. Based on above perspectives, this study was aimed to investigate the physico-chemical parameters and bacterial community along the coastal waters of Pulau Tuba, Langkawi. Materials and Methods Study area: The Langkawi Archipelago (6o18’ N, 099o 47’ E) is located in the Andaman Sea, 30 km west of the northern end of Peninsular Malaysia at the border between Malaysia and Thailand.

The archipelago consists of 104 islands during the low tide and 99 islands during the high tide. Pulau Tuba is one of the largest islands in Langkawi which posses a unique ecosystem covering terrestrial, aquatic and mangrove areas. Samples were collected from 4 different stations (Fig. 1). Pulau Tuba Jetty (6o15’ 25.2" N, 99o51’ 26.1" E) - station 1, Simpang Tiga (6o13’ 7.2" N, 99o49’ 30.2" E) – station 2, aquaculture site (6o15’ 1.5" N, 99o49’ 25.7") – station 3 and Kuah Jetty (6o18’ 19.8" N, 99o50 53.1" E) – station 4. Sampling techniques and sites: A field observation on physicochemical characteristics of water was carried out from June 2005 to May 2006 along the coastal waters Pulau Tuba, Langkawi. The physico-chemical parameter such as temperature, salinity, total dissolved solids (TDS), total suspended solids (TSS) and the conductivity of surface and bottom (6.5 meter) of the sea water was identified using Hydrolab, DSA 5, while pH was measured by pH meter. Nitrate, nitrite, phosphate and chlorophyll a content were determined using standard method (Parsons et al., 1984). Purification of bacterial isolates: After direct counting, the morphology of colonies was observed and colonies with different morphology were isolated from Zobell’s modified media using sterile tooth pick and patched on new TSA agar plates. Each colony was designated by a number with separating differences of its sources of samples. After 24 hrs of incubation at 37oC, the individual colony that showed growth on all the plates were picked and streaked on fresh TSA plates and incubated at 37oC. Each of the colonies was sub-cultured again on fresh TSA plates to obtain pure culture. For longer storage, the cultures were preserved in glycerol stock at 80oC. analytical Profile index (API 20E) was used to identify the

Fig. 1: Location of sampling sites (Stations 1-4) along coastal waters of Pular Juba, Langkawi Journal of Environmental Biology ‹July 2012‹

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Studies on bacterial community bacteria as it is 98% accurate for the identification of Gram-negative rods (Drancourt et al., 2000). Statistical differences in water quality among the sampling stations were assessed using two-way ANOVA. The data were transformed using log10[x+1] to normalize their distribution for statistical analysis (Rezai et al., 2003). Results and Discussion The physico-chemical parameters such as temperature (27.43-28.88oC), DO (3.79-6.49 mg l-1), pH (7.72-8.20), salinity (33.10-33.96 ppt), TDS (32.27-32.77 g l-1) and specific conductivity (49.83-51.63 mS cm-1) at the surface and the bottom level were determined (Table. 1). The results indicate that there were no significant variations on physico-chemical parameters of water among the four different stations along the months. This supports the findings of the studies carried out by Kamaruzzman et al. (2003). There were no significant differences on limnological profile among the coastal waters of Port Dickson and Malacca. It indicates that the Langkawi coastal waters are well mixed (Ruyitno et al., 2003). The dissolved inorganic nutrients showed significant differences in NO3, NO2- and PO43- level among the stations. In fact station 3 (26.93 µg at N l-1) and station 4 (14.61 µg at N l-1) showed highest amount of nitrates than those of stations 1 (2.04 µg at N l-1) and station 2 (4.18 µg at N l-1) (Table 2). Monthly variation in water nutrient level showed higher concentration of NO--3, NO -2, PO3 -4 and Chl a at Station 3 (Apr 2006), Station 4 (Apr 2006), Station 3 (May 2006) and Station 4 (Oct 2005), respectively while the lowest concentration was observed at Station 1 (July 2005), Station 1 (Nov 2005), Station 1 (July 2005) and Station 2 (May 2006), respectively (Fig. 2). High level of dissolved inorganic nutrients at station 3 might be due to its surrounding mangrove area pore water that flow from the upper sediment horizon to the tidal creek and subsequently to the estuary. The products of leaf litter decomposition in the mangrove

Nitrate (mg l-1)

Nitrite (Pg l-1)

sediment provided the bulk of inorganic and organic load in the tidal creek, as evident from our analysis during inorganic nutrients in four stations. The net export of these degradation products from the mangrove was about 20% of total litter fall (Kamaruzzaman et al., 2003). The increased rates of nutrients at the station 4 might be due to the influx of anthropogenic inputs and waste discharges containing nitrogen and phosphorous compounds from river runoff to the environments (Ruyitno et al., 2003; Tripathy et al., 2005). The high concentration of chlorophyll a was noted at station 4 in October, 2005 (Table 2). This may due to the monsoonal runoff wherein high concentrations of nutrients are brought to these environments stimulating a rich phytoplankton growth (Siti zubiadah et al., 2003). It may well suggest the presence of detrimental matter in this non-turbulent region which could be attributed to the composition of organic matter from the sediment and community structure, harbouring in the surrounding water. The study mainly focussed on Gram-negative bacteria to serve as data base for identifying Gram-negative pathogenic bacteria and hydrocarbon degraders. Out of 13 Gram-negative bacteria identified, dominant Gramnegative bacteria were from Enterobacteriaceae family. It was interesting to note that oil biodegrading Pseudomonas putida was identified from Station 2 indicating that this station had oil pollution which might be from various man made sources like oil discharge from boat etc. Six human pathogenic bacteria were identified from Station 3 (Vibrio vulnificus, Stenotrophomonas maltophilia, Chryseomonas luteola Pantoea spp, Proteus mirabilis and Providencia alcalifaciens). These bacterial species might enter the fin fish and shell fishes hence a detailed study is need to be carried out to enumerate the bacterial load from the fishery resources of this area to check their quality for the human consumption. Pneumonia causing Gram-negative bacteria were isolated both from Station 1 and Station 4 (Burkholderia cepacia and Klebsiella oxytoca

Phosphate (Pg l-1)

Chlorophyll a (Pg l-1 )

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Table 1 : Mean water quality parameters at the surface and bottom level of the four stations from June 2005 to May 2006 Stations

Depth

Temperature (ºC)

pH

Specific conductivity (mS cm-1)

Salinity (ppt)

TDS (g l-1)

DO (mg l-1)

1

Surface Bottom

28.87±0.02a 28.51±0.44a

8.20±0.01a 8.18±0.18a

50.53±0.59a 49.83±1.61a

33.37±0.67a 33.34±0.30a

32.60±0.53a 32.27±0.38a

5.86±0.14a 3.79±0.26ab

2

Surface Bottom

27.79±0.10a 27.43±0.12a

8.09±0.08a 8.17±0.06a

51.43±0.32a 51.27±0.31a

33.10±0.62a 33.96±0.01a

32.67±0.06a 33.17±0.08a

6.16±0.02a 5.95±0.03a

3

Surface Bottom

28.88±0.02a 28.20±0.18a

7.72±0.12a 7.90±0.26a

51.40±0.15a 50.93±0.83a

33.80±0.17a 33.94±0.04a

32.77±0.15a 33.14±0.16a

6.49±0.53a 5.68±0.06a

4

Surface Bottom

29.45±0.10a 28.28±0.15a

8.16±0.01a 8.14±0.03a

51.29±0.26a 51.63±0.31a

33.74±0.05a 33.82±0.05a

32.59±0.16a 32.48±0.06a

5.24±0.08a 5.62±0.10a

Mean values with standard error within same column are not significantly different (P>0.05) Table - 2: Yearly average nitrate, nitrite, phosphate and Chl a (µg l-1) level in the four stations from June 2005 to May 2006 Stations

NO3-

NO2-

PO43-

Chl a

1 2 3 4

2.04±1.06a 4.18±0.50b 26.93±0.31c 14.61±0.23d

0.86±0.02a 2.04±0.06b 2.74±0.08bc 4.03±0.12d

0.27±0.01a 0.52±0.05a 1.33±0.03a 1.07±0.01a

5.67±0.39a 6.57±1.07a 9.75±0.98ab 12.4±1.59ab

Data represented as mean±SE. Values in each column having the different superscripts are significantly different (P < 0.05). Table 3: List of Gram-negative bacteria isolated from the different sampling stations Sampling stations

Identified bacterial species

Station 1

Burkholderia cepacia Serratia liquefaciens

Station 2

Acinetobacter baumannii Pseudomonas putida

Station 3

Vibrio vulnificus Stenotrophomonas maltophilia Chryseomonas luteola Pantoea spp Proteus mirabilis Providencia alcalifaciens

Station 4

Aeromonas hydrophila group I Klebsiella oxytoca Serratia odorifera 1

Fig. 3: Total number of bacteria (CFU ml-1) corresponding to each designated stations Journal of Environmental Biology ‹July 2012‹

respectively) and common fish pathogens like Serratia liquefaciens and Aeromonas hydrophila group 1 were also identified from the same stations (Table 3). The higher number of bacterial colony (CFU ml-1) was observed at surface level of Station 4 (~3400 CFU ml-1 in water column, followed by its bottom level (2850 CFU ml-1) indicating that there is high nutrient flow in the station 4 area helping in proliferating bacterial colonies. Heavy discharge of anthropogenic wastes and domestic sewage runoff in this area would help in high organic matter load at Station 4 which ultimately leads to heavy bacterial load in this station. Station 3 showed 1760 CFU ml-1 bacterial colonies at the surface layer and 2110 CFU ml-1 at sediment bottom. It was lowest at Station 2 with 890 CFU ml-1 at surface and 1100 CFU ml1 in sediment. Bacterial load at Station 1 was comparatively higher than Station 2 but lower than Station 3 and Station 4 with 1550 CFU ml-1 at surface water and 1250 CFU ml-1 at sediment level (Fig. 3). The present study focussed on the existing environmental status of costal water Pulau Tuba. Furthermore, knowledge of the physico-chemical and biological processes in the coastal waters is essential in order to understand the mechanism involved in the distribution of pollutants from their points of entry in the open sea. The finding of this study portrays that the water quality along the coastal water Pulau Tuba Langkawi is well mixed. Nevertheless, the sewage outflow from the city and suburbs is directly discharged into the sea near ‘Jetty Kuah’ which substantially increase organic load in water body in this commercial shipping area. According to USEPA (2001), sediments and river extending from the city could serve as a reservoir for bacterial and chemical pollutants therefore a potential source of pollutants to the water column, organisms, and

Studies on bacterial community ultimately to the human through food chain. These pollutants arise from a number of sources, including municipal and industrial discharges, urban and agricultural runoff, atmospheric deposition and port operations would pave the way to the colonization of multi resistance bacteria in this water body. Hence, long term monitoring program would enable us to understand the chemical and bacterial load which ultimately facilitate in formulating proper management plan to sustain the conducive water quality at the coastal waters of Langkawi Island, Malaysia Acknowledgments The authors wish to express their gratitude to Oceanography Laboratory teams, Faculty of Science and Technology for their invaluable assistance and hospitality throughout the sampling period. References Caldwell, D.E.: The microstat: Steady state microenvironments for subculture of steady state consortia, communities and microecosystems. In: Trends in Microbial Ecology (Eds.: R. Guerrero and C. Pedros-Alio). Spanish Society microbiology Barcelona, 123-128 (1993). Chau, K.W.: Persistent organic pollution characterization of sediments in Pearl River estuary. Chemosphere, 64, 1545-1549 (2006). Bong, C.W. and C.W. Lee: Nearshore and offshore comparison of marine water quality variables measured during SESMA 1. Malay. J. Sci., 27, 25-31 (2008). Drancourt, M., C. Bollet, A. Carlizo, R. Martelin Gayral, Jean-pierre and D. Raoult: 16S ribosomal DNA sequence analysis of a large collection of environmental and clinical unidentifiable isolates. J. Clin. Microbiol., 38, 3620-3623 (2000). Helbling, E.W., E.R. Marguet, V.E. Villafane and O. Holhansen: Bacterioplankton viability in Antarctic waters as affected by solar ultraviolet radiation. Mar. Ecol. Prog. Ser., 126, 293-298 (1995). Jalal, K.C.A., Y. Kamaruzzaman, A. Fairuz, B. Akbar, S. Shahbudin and Y. Faridah: Bacterial communities in Kuantan estuary of Pahang Malaysia. J. Appl. Sci., 10, 652-657 (2010). Japar Sidik, B., A. Azizi, Z. Muta Harah and K. Akito: Aquatic resource and environmental studies of the Straits of Malacca. Managing the straits through science and technology. MASDEC, JICA. p. 381 (2003). Kamaruzzaman, B.Y., Y. Rosnan, H. Mohd. Lokman, N.A.M. Shazili and

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Journal of Environmental Biology ‹July 2012‹