Most Probable Number Research Articles

ISOLATION OF MULTI DRUG RESISTANT BACTERIA FROM BORE WATER SAMPLES IN AND AROUND VISAKHAPATNAM

Objective: The aim of the present study was to determine the levels of groundwater contamination by isolating total coliforms, fecal coliforms, and bacterial pathogens.
 Methods: A total of 32 water samples, comprising 5 samples from each GVMC urban area zone, Visakhapatnam were randomly collected from different areas. Evaluation of Total and fecal coliform counts was done by using multiple-tube fermentation technique and were reported as the most probable number (MPN) of organisms present per 100 ml of sample.
 Results: The samples collected from the zones Yendada (zone I), Marripalem (zone IV), Chinna musidiwada (zone VI) showed the highest total and fecal coliform counts (MPN>180). Nearly 30 samples (94%) yielded bacterial isolates. Among the isolates Pseudomonas spp. showed highest susceptibility to cefepime and imipenem antibiotics. All the microorganisms isolated were multidrug resistant with a multidrug antibiotic resistant index more than 0.2.
 Conclusion: These multidrug-resistant (MDR) organisms are considered as a major threat to the public health and should receive more attention.

Reduction of microbial populations and cross-contamination of Salmonella Typhimurium and the surrogate Enterococcus faecium on tomatoes during triple-wash using off-label concentrations of a combination of peroxyacetic acid and hydrogen peroxide

This study aims to determine the minimal concentrations of a 23% hydrogen peroxide and 5.3% peroxyacetic acid (H2O2-PAA) mixture required to prevent microbial cross-contamination of Salmonella and the potential surrogate Enterococcus faecium on tomatoes. Nalidixic acid-resistant (NaL) S. Typhimurium (5.15 log10MPN/g) or E. faecium (5.29 log10MPN/g) inoculated tomatoes were triple-washed for 45 s at each step using a water + antimicrobial + water (WAW) or water + water + antimicrobial (WWA) wash strategy with a solution of H2O2-PAA at 0 (control) and off-label concentrations of 0.50 and 0.70%. A most probable number (MPN) method was used to analyze the microbial reductions and cross-contamination trasnferred cell counts. Significant reductions (P < 0.05) of Salmonella were only achieved when the off-label concentration of 0.7% H2O2-PAA was applied using the WWA strategy. When LS-Means were calculated, there were no significant differences (P > 0.05) in reductions of S. Typhimurium or E. faecium regardless of wash strategy. Cross-contamination of S. Typhimurium was prevented at 0.7% of H2O2-PAA using the WWA strategy, and E. faecium was prevented at and above 0.50% of H2O2-PAA, respectively, regardless of wash strategy. There were no differences (P > 0.05) of bacterial cell survival in triple-wash solutions between S. Typhimurium and E. faecium. Results suggested that E. faecium could be an acceptable surrogate for S. Typhimurium when validating antimicrobial washing systems on tomatoes. The off-label concentrations of H2O2-PAA that were tested resulted in non-detectable microbial cross-contamination. Off-label use of antimicrobials is not encouraged until future research determines the safety of these greater concentrations prior to their implementation in commercial settings.

The Prevalence of Bacteria Commonly Related to the Production of Mussels and Oysters in Saldanha Bay

Bivalve molluscs are a good source of high quality protein and perform important ecological functions. Their ability to bioaccumulate materials in their soft tissues makes them suitable aquatic species for biomonitoring of environmental conditions. The discharge of treated and untreated sewage into the bivalve-growing areas is a concern. The aim of this study was to investigate the prevalence of bacterial microbiota in shellfish farms in Saldanha Bay harbour using pathogens commonly associated with shellfish-related foodborne disease outbreaks. Seawater and mussel samples were collected from five sampling points located in three sampling locations. Oyster samples were collected from the harbour deck immediately after harvesting by the farmers. The most probable number (MPN) method was used to enumerate E. coli and faecal coliforms. Cultural methods were used for the detection of Salmonella and Vibrio spp. The E. coli concentrations for 15 March and 14 July are &lt;0.18 MPN/100 ml at all sampling sites and for 25 August, &lt;0.18 MPN/100 ml for all sampling sites except sampling site SP2 (0.2 MPN/100 ml). Spikes were observed on the total MPN counts in winter. Salmonella and Vibrio spp. were not detected. However, other bacterial species were identified through their phenotypic profile using the VITEK 2 system. Based on the low E. coli-MPN concentrations, the study concluded that the molluscs were safe for human consumption. Further studies need to be conducted on the bacterial species identified.

Evaluation of the Export of Fecal Contamination from Roadside Green Infrastructure

Fecal contamination in stormwater runoff is a leading contributor of waterbody impairment in the US, and green infrastructure (GI) has demonstrated variable performance in its mitigation. Therefore, there is a need for studies that use robust sampling methods to quantify concentration and load reductions as well as evaluate export of fecal contamination with respect to other water quality constituents. The objective of this study was to characterize the performance of various types of GI systems in mitigating fecal contamination [measured as Escherichia coli (EC)] in highway stormwater runoff. This study was conducted at a field site on Lorton Road in Fairfax County, Virginia, where a bioretention, bioswale, compost-amended grass channel and a grass channel were instrumented for 2 years in all seasons for flow-weighted composite sampling and volume monitoring. The bioretention effectively reduced EC concentration and loading from a relatively high inflow concentration [1,120 most probable number (MPN)/100 mL]. The swales, however, consistently increased EC concentration from their relatively low average inflow concentration of 58 MPN/100 mL but had no significant impact on mass load. For all GI systems, outflow concentrations were regularly above recreational water quality standards. Regression analyses indicated that average daily temperature, dissolved organic carbon, total dissolved nitrogen, and chloride were significantly correlated with the log-transformed EC concentrations exiting the GI systems. We conclude that EC export is prevalent in varying degrees in the studied GI systems such that the bioretention reduces its presence, whereas the swales often increase its presence. This study provides insight into environmental factors and common stormwater quality constituents that are correlated with the export of fecal contamination from GI.

Assessment of Physico-chemical and Bacteriological Quality of Drinking Water Sources in Kakamega County, Kenya

Water-borne diseases still present a major health burden in Africa. Large segments of the rural population here have no access to potable water. This study has been designed to assess the physico-chemical and bacteriological quality of drinking water sources in the study area. The study was conducted in Kakamega county covering the twelve sub-counties of Likuyani, Lugari, Malava, Navakholo, Lurambi, Ikolomani, Shinyalu, Mumias East, Mumias West, Matungu, Butere and Khwisero. Socio-demographic characteristics of the study populations were captured using a structured pre-tested questionnaire. The Most Probable Number (MPN) method was used to determine the abundance of Total coliforms and Escherichia coli (E. coli) in the water samples collected. Physico-chemical analyses (Temperature, pH, Electrical conductivity, Total dissolved solids and Dissolved oxygen) were carried out. Free residual chlorine was determined by colorimetric method with DPD chlorine tablets. The analyses were conducted following guidelines of American Public Health Association and WHO. Only 17% (68/400) of the study population had access to piped water in the study area. Waste management practices of the localities was found poor as more than 62 % (248/400) of the respondents dispose waste materials in open fields. All drinking water sources investigated were contaminated with Total coliforms. There was a wide variation in Total coliforms and E. coli. Total coliform counts ranged from 0.0 - 3652.5 cfu/100 ml whereas E. coli ranged from 0.0 - 33.0 cfu/100 ml. Both Rivers/streams and unprotected dug wells recorded the highest number of Total coliforms and E. coli. Piped water, Rainwater collection and Boreholes recorded the lowest number of Total coliforms and E. coli. E. coli counts in most drinking water sources investigated exceeded the maximum permissible limits set by WHO/KEBS, implying that they are not safe for household applications without prior treatment. The results indicate that protected drinking water sources (piped water, boreholes, protected dug wells and protected springs) are subjected to a high level of fecal contamination in the study area. Construction flaws on casing, concrete covers, fences, diversion ditches, and protection of springs' eyes and other plumbing accessories could be one of the causes. Protected water sources may become contaminated for other reasons, such as a lack of frequent surveillance, disinfection, and correct maintenance. Poor sanitation practices, a lack of hygiene education, poor supervision and maintenance, and inconsistent water point disinfection can all be blamed for the high levels of E. coli. The recorded temperature and pH ranged between 19.9–27.2°C and 4.8 - 9.1, respectively. Turbidity and Electric conductivity of the water samples ranged, respectively, between 0.43–467.02 NTU and 18.7–510.7 μS/cm. Residual chlorine in piped water showed a range of 0.06-1.2 ppm. In addition, Total dissolved solids were found to be between 20.1 and 639.2 mg/l; whereas Dissolved oxygen ranged from 2.2- 15.4 mg/l. The results of the current investigation showed that some bacteriological and physico-chemical parameters of the various water sources had values above the maximum permissible limits advised by WHO/KEBS. The Water sector stakeholders in the area should put in place proper intervention measures which include raising public awareness on the water quality of drinking water sources and enhancing the current infrastructure in order to reduce any potential health hazards.

Environmental Drivers of Vibrio cholerae Abundances in Mobile Bay, Alabama.

Vibrio cholerae is the etiological agent of the illness cholera. However, there are non-O1/non-O139 V. cholerae (NOVC) strains that generally lack the toxin gene (ctx) and colonization factors that cause cholera. These NOVC strains are autochthonous members of estuarine environments and a significant cause of seafood-borne gastroenteritis in the United States. The objective of this study was to identify environmental parameters that correlate with NOVC prevalence in oysters, water, and sediment at three ecologically diverse locations in Mobile Bay, AL, including Dog River (DR), Fowl River (FR), and Cedar Point (CP). Oyster, water, and sediment samples were collected twice a month when conditions were favorable for NOVC growth and once a month when they were not. A most probable number (MPN)/real-time PCR assay was used to determine NOVC abundances. Environmental parameters were measured during sampling to determine their relationship, if any, with NOVC at each site. NOVC abundances in oysters at DR, FR, and CP were 0.87, 0.87, and -0.13 log MPN/g, respectively. In water, the median NOVC levels at DR, FR, and CP were 1.18, -0.13, and -0.82 log MPN/mL, and in sediment, the levels were 1.48, 1.87, and -0.03 log MPN/g, respectively. Correlations of NOVC abundances in oyster, water, and sediment samples with environmental parameters were largely site specific. For example, the levels of NOVC in oysters at DR had a positive correlation with temperature but a negative correlation with dissolved oxygen (DO) and nutrient concentrations, NO2-, NO3-, dissolved inorganic nitrogen (DIN), total dissolved nitrogen (TDN), and dissolved inorganic phosphorus (DIP). At FR, however, the levels of NOVC in oysters displayed only a negative correlation with NO2-. When grouping NOVC abundances by temperature, the main driving factor for prevalence, additional correlations with salinity, total cell counts, dissolved organic nitrogen (DON), and dissolved organic carbon (DOC) became evident regardless of the site. IMPORTANCE NOVC can cause gastrointestinal illness in humans, which typically occurs after the consumption of raw or undercooked seafood. Incidence rates of NOVC gastroenteritis have increased during the past decade. In this study, NOVC was enumerated from oysters, sediment, and water collected at three sites in Mobile Bay, with environmental parameters measured concurrently over the course of a year, to identify potential environmental drivers of NOVC abundances. The data from this study, from an area lacking in V. cholerae research, provide a useful baseline for risk analysis of V. cholerae infections. Defining correlations between NOVC and environmental attributes at different sites and temperatures within a dynamic system such as Mobile Bay provides valuable data to better understand the occurrence and proliferation of V. cholerae in the environment.

Cryopreservation of two species of the multicellular volvocine green algal genus Astrephomene

BackgroundAstrephomene is an interesting green algal genus that, together with Volvox, shows convergent evolution of spheroidal multicellular bodies with somatic cells of the colonial or multicellular volvocine lineage. A recent whole-genome analysis of A. gubernaculifera resolved the molecular-genetic basis of such convergent evolution, and two species of Astrephomene were described. However, maintenance of culture strains of Astrephomene requires rapid inoculation of living cultures, and cryopreserved culture strains have not been established in public culture collections.ResultsTo establish cryopreserved culture strains of two species of Astrephomene, conditions for cryopreservation of the two species were investigated using immature and mature vegetative colonies and two cryoprotectants: N,N-dimethylformamide (DMF) and hydroxyacetone (HA). Rates of cell survival of the A. gubernaculifera or A. perforata strain after two-step cooling and freezing in liquid nitrogen were compared between different concentrations (3 and 6%) of DMF and HA and two types of colonies: immature colonies (small colonies newly released from the parent) and mature colonies (large colonies just before daughter colony formation). The highest rate of survival [11 ± 13% (0.36–33%) by the most probable number (MPN) method] of A. gubernaculifera strain NIES-4017 (established in 2014) was obtained when culture samples of immature colonies were subjected to cryogenic treatment with 6% DMF. In contrast, culture samples of mature colonies subjected to 3% HA cryogenic treatment showed the highest “MPN survival” [5.5 ± 5.9% (0.12–12%)] in A. perforata. Using the optimized cryopreservation conditions for each species, survival after freezing in liquid nitrogen was examined for six other strains of A. gubernaculifera (established from 1962 to 1981) and another A. perforata strain maintained in the Microbial Culture Collection at the National Institute for Environmental Studies (MCC-NIES). We obtained ≥0.1% MPN survival of the A. perforata strain. However, only two of the six strains of A. gubernaculifera showed ≥0.1% MPN survival. By using the optimal cryopreserved conditions obtained for each species, five cryopreserved strains of two species of Astrephomene were established and deposited in the MCC-NIES.ConclusionsThe optimal cryopreservation conditions differed between the two species of Astrephomene. Cryopreservation of long-term-maintained strains of A. gubernaculifera may be difficult; further studies of cryopreservation of these strains are needed.

Cultivation-dependent and cultivation-independent investigation of O-methylated pollutant-producing bacteria in three drinking water treatment plants

O-methylated pollutants (OMPs) are emerging contaminants in drinking water and mainly produced through bacterial O-methylation. However, the information of OMP-producing bacteria (OMPPB) in drinking water treatment plant (DWTP) is largely unknown so far. In this study, the OMPPB in water samples from three DWTPs (XL, JX and NX) were investigated by using cultivation-dependent and cultivation-independent technologies. Four OMPs were detected and their odor and toxicity risks were assessed. Formation potentials (FPs) of 2,4,6-trichloanisole, 2,3,6-trichloanisole, 2,4,6-tribromoanisole, pentachloroanisole and diclofenac methyl ester were determined in water samples and their values shifted significantly among DWTPs. A most probable number (MPN) method was established to quantify OMPPB numbers and the relationships between total haloanisole FPs (HAFPs) (y) and OMPPB numbers (x) in three DWTPs could be described by the following functions: y = 0.496×0.373 (XL), y = 0.041×0.465 (JX) and y = 0.218×0.237 (NX). Several genera like Bacillus, Ralstonia, Brevundimonas, etc. were newly found OMPPB among the cultivable bacteria, and their OMP products were evaluated in terms of quantity and environment risks (odor, toxicity and bioaccumulation). High-throughput sequencing revealed treatment process was the main driving factor to shape the OMPPB community structures and Mantel test showed HAFP profile was significantly influenced by Mycobacterium and Pelomonas. PICURSt2 analysis discovered four phenolic O-methyltransferases (OMTs) and four carboxylic OMTs which might be responsible for OMP formation. Several strategies were recommended to assess risk and control contamination brought by OMPPB in DWTPs.

Development and Verification of a Poultry Management Tool to Quantify Salmonella from Live to Final Product Utilizing RT-PCR.

The United States Department of Agriculture Food Safety and Inspection Service (USDA FSIS) does not maintain a zero-tolerance policy for Salmonella in poultry and poultry products, despite being a known food safety hazard throughout the poultry industry. In 2016, USDA FSIS established performance standards for a 52-week moving window with the maximum acceptable percent positive for comminuted turkey (325 g sample) at 13.5% (7 of 52 samples). Based upon FSIS verification sampling results from one 52-week moving window, the Salmonella prevalence for each poultry establishment in category 1 (below limit), 2 (meeting limit), or 3 (exceeding limit) are published for public viewing. Moreover, many poultry producers continue to have post-intervention samples test positive. Therefore, the use of quantification would be more valuable to determine the efficacy of process control interventions, corrective actions, and final product Log CFU/g of Salmonella to make rapid, within shift, food safety decisions. Therefore, the objectives of these studies are to develop, verify, and validate a rapid and reliable quantification method utilizing RT-PCR to enumerate Salmonella in the poultry industry from flock to final product and to utilize the method in an application study. BAX® System SalQuant® is an application of the BAX® System Real-Time PCR Assay for Salmonella to enumerate low levels of Salmonella with shortened enrichment times. Curve development encompassed inoculating poultry matrix samples at four levels with an ATCC strain of Salmonella, with three biological replicates per inoculation level, and five technical replicates being run on the BAX® System for various timepoints, gathering the data, and creating a linear-fit equation. A linear-fit equation was provided for each timepoint. The ideal timepoint, based on the statistical parameters surrounding the equation (R2 &gt; 0.80, Log RMSE &lt; 0.60, and enumerable range 0.00 to 4.00 Log CFU/mL (g)) that most accurately estimate Salmonella compared to most probable number (MPN), was chosen to be utilized for further studies.

Escherichia coli POLLUTION IN COASTAL LAGOON AND DAM RESERVOIR: REPERCUSSIONS ON PUBLIC HEALTH AND AQUACULTURE

Escherichia coli are rod-shaped gram-negative bacteria naturally present in the lower intestinal tracts of warm-blooded organisms including humans and are often released into the environment through faecal material and wastewater effluent. The presence of E. coli in waters has long been regarded as an indicator for recent faecal contamination, and possible presence of other more harmful enteropathogens. This study examined the total coliform load and occurrence of E. coli to determine the microbial water quality of Merchang Lagoon on Terengganu coast facing the South China Sea, and Raban Lake, part of the Chenderoh Hydroelectric Dam reservoir in the Lenggong Valley, Perak. Water samples were collected from three sites in the lagoon, and two sites in the lake. Total coliform load in water was enumerated by most probable number (MPN) method, and E. coli isolation was carried out using eosin methylene blue (EMB) agar. The results showed greatly varied total coliform counts from site to site in both the lagoon (site 1: 7; site 2: 220; site 3: 920 CFU/100 mL) and lake (site 1: 220; site 2: 1600 CFU/100 mL). All sites showed presence of E. coli. The results suggest faecal pollution, and the impact of water stagnation and human activities on the coliform load. The impacts of faecal pollution on public health and aquaculture in the investigated areas are discussed. Long-term monitoring of faecal pollution constitutes the essential part of environmental conservation and preservation against the risk of waterborne faecal pathogens in recreational and commercial activities.

Analysis of Contamination of Total Microbes, Coliform, Escherichia coli, and Staphylococcus aureus in Elementary School Children’s Snacks in Jimbaran area, Bali, Indonesia

School-age children like buying snacks after school. The snacks are sold on the roadside, therefore making them vulnerable to bacterial contamination, such as Coliform, Escherichia coli, and Staphylococcus aureus that cause foodborne diseases. Jimbaran is in South Kuta, Badung, Bali. There are 20 elementary schools in Jimbaran with 7,321 students. The purpose of this research was to determine pathogenic bacterial contamination in snacks. Sampling was done using Simple Random Sampling method, by selecting three types of snacks from five different elementary schools in Jimbaran. Testing pathogenic bacterial contamination using total plate count (TPC), Most Probable Number (MPN), and Staphylococcus aureus test. The results showed the highest average total microbes in cubit cake at Elementary School E is 34.06×104 CFU/g. The highest average of Coliforms in fried tofu at Elementary School B was 92.27×102 MPN/g. The highest average E. coli in omelets roll at Elementary School C was 63.93×102 MPN/g. The highest average S. aureus in cakkue cake at Elementary School D was 92.9×102 CFU/g. The conclusion were 45 samples had total microbial contamination, 22 samples were positive for Coliform, 16 samples were positive for E. coli, and 40 samples were positive for S. aureus. According to Indonesian Food Safety Standards (BPOM RI), 4.4% of the snacks tested were suitable for consumption, while 95.6% were not suitable for consumption.

Distribution of multiple antibiotic-resistant Gram-negative bacteria in potable water from hand-dug wells in Iwo, Nigeria

AbstractThe provision of potable water is a global challenge. Infections caused by drinking contaminated water are a regular occurrence in developing countries. This study was carried out to determine Gram-negative bacterial distribution and antibiotic resistance in potable water from hand-dug wells within Iwo, Nigeria. Thirty hand-dug wells were randomly selected within Iwo for sampling carried out between October and December 2018. Bacteria identification was carried out using standard methods. The most probable number (MPN) and antibiotic resistance profile as well as Multiple Antibiotic Resistance Index (MARI) for these isolates were determined in addition to studying their haemolysis patterns on blood agar. Results showed that all the water samples from these hand-dug wells were highly contaminated. The highest value &amp;gt;1,100+ was recorded for 21 samples. In addition, 11 genera of bacteria were isolated: Citrobacter, Enterobacter, Escherichia, Klebsiella, Morganella, Neisseria, Proteus, Providencia, Salmonella, Serratia and Pseudomonas. Antibiotic resistance to cefixime and cefuroxime were 92.6 and 90.9%, respectively. One hundred and sixty-nine (96.6%) isolates had a MARI greater than 0.2 and all showed haemolysis. Ingestion of this contaminated water has major public health implications. Hence, it is advisable that every individual should embark on in-house water treatment to avoid water-borne diseases.

Diversity in Infection Specificity between the Bloom-forming Microalga &lt;i&gt;Heterosigma akashiwo&lt;/i&gt; and Its dsDNA Virus, Heterosigma akashiwo Virus

Heterosigma akashiwo virus (HaV) is a dsDNA virus that infects the bloom-forming raphidoflagellate Heterosigma akashiwo. Both the host and its virus are phenotypically diverse in terms of infection specificity. Their relationships have been examined based on the occurrence or absence of algal lysis following virus inoculation; however, variations in the strain-level host-virus relationship regarding infectivity and lysis rates remain unclear. Therefore, we performed a series of cross-infectivity tests using 60 H. akashiwo and 22 HaV strains isolated from the coastal waters of western Japan. The host strains were divided into 5 different groups and viruses into 4 groups. Using a representative strain from each group, algal lysis was observed in 14 of the (5×4=) 20 host-virus combinations; the concentration of infectious units in each HaV suspension was then assessed using the most probable number (MPN) assay on the five host strains. Virus titers ranged between 1.1×101 and 2.1×107 infectious units mL-1; the titer of each viral lysate was differently estimated using distinct H. akashiwo strains as hosts. These results suggest that (1) a clonal viral lysate comprises virions with different intraspecific infection specificities and/or (2) the efficiency and error rates of each intracellular replication process vary in each host-virus combination.

Microbiological Quality of Drinking Water and Food in a Rural Community

Safe water and food are essential for good human health. The contamination of water with infected fecal bacteria is common in areas with poor standards of hygiene and sanitation. This study investigated total coliform bacteria, fecal coliform bacteria, and E.coli in drinking water and food stalls using water from a rural community, where the rural living conditions increase the risk of water-related diseases. In total, 40 samples of bottled drinking water, 50 water samples from vending machines, 30 samples of household drinking water, 30 food samples were collected from household food, and 60 food samples were collected from food stalls, and coliform bacteria contamination was determined using the most probable number (MPN) technique. The results revealed that all the water and food samples contained coliform bacteria contamination, while all the water samples and 50% of the food samples contained fecal coliform bacteria. The numbers of household food samples contaminated with coliform bacteria and E.coli were 29 (97%) and 12 (40%), respectively. Entrepreneurs should be regularly maintaining clean drinking water vending machines. The government sector should be urgently solving the problem of drinking water standards to ensure suitable consumer safety.

Evaluation of the microbiological quality of water for human consumption and irrigation in regions of Alagoas

Well water is one of the most accessible and indispensable sources for populations that do not have access to the public water supply network. This must be free from pathogenic microorganisms so that it is considered of good quality for consumption. The lack of monitoring of water sources and the population's ignorance of the causes and problems associated with contamination can lead people to acquire several waterborne diseases. This study aimed to evaluate the presence of thermotolerant coliforms in water used for human consumption in seven wells in the state of Alagoas, using the most probable number (MPN) technique. Seven water samples were collected and analyzed in two communities, 5 in a community located in the Alagoas Forest zone and 2 in the Alagoas wild. According to the microbiological analyzes carried out in this work, the results showed that the water used by communities in the interior of the state of Alagoas, was identified as an important risk factor to the health of the population, since all water sources analyzed present indices of total coliforms and E. coli above those allowed for human consumption. Regarding irrigation, only 43% of the samples are suitable for irrigation.

Bacteriological Study of Some Sachet Water Sold in Ogbomoso Metropolis and its Public Health Significance

The introduction of sachet water to consumers was to provide safe, hygienic and affordable instant drinking water to the public. Although this is a laudable idea, current trends seem to suggest that sachet drinking water could be a route of transmission of diseases. The objective of this study was to check the bacteriological safety or otherwise of some sachet water packaged in Ogbomoso metropolis. Using a simple random procedure, fifteen brands of sachet water were bought from vendors at different locations. The samples were analyzed using multiple tubes methods and biochemical assays. Results were recorded as Most Probable Number (MPN) of coliform per 100ml of water. The bacteriological quality of the samples was assessed based on the World Health Organization (WHO) classification system for drinking water. Zero (0%) of the sample was Excellent, two (2) (13.3%) were Satisfactory, one (1) (6.7%) was Suspicious and twelve (12) (80%) were Unsatisfactory using the MPN values recorded. The samples were contaminated with faecal coliform. Escherichia coli was detected in some of the samples which could have caused diarrhea, cramps, nausea and other symptoms in the consumers. The level of contamination could be due to inadequate treatment of water samples by the producers, improper use of filters or post-production contamination. The findings suggest the need to enforce the laws that govern the operation of such production outfits as well as educating consumers on the need to purchase sachet water from manufacturers that have been licensed to produce water and whose product bears the stamp of the National Agency for Food and Drugs Administration and Control (NAFDAC). And producers should ensure proper purification of water and maintain hygienic environment for producing the sachet water.

Effects of different fermentation starter cultures on the quality of fish sauce prepared from deep-sea smelt

This study investigated deep-sea smelt fish sauces made with three types of starter cultures to produce a high-quality product that contains low histamine levels. The starter cultures included lactic acid bacterium Tetragenococcus halophilus for soy sauce and T. halophilus strains 8-25 and 14-1 that do not receive the histidine decarboxylase gene, isolated from fermented marine foods. The addition of these bacteria reduced the pH of the fish sauce mashes (moromis) to below 5.0 in the first 21 days. This pH level was maintained until the end of fermentation. Throughout fermentation, histamine-producing bacterial counts and histamine levels in the moromis were below 9.3 × 10 most probable number (MPN)/g and 113 mg/L, respectively. A principal component analysis of the final products revealed that taste, which was obtained using a taste sensor, and quality indicators (physicochemical and extractive components) differed among the three products.

Dampak Perilaku Masyarakat Membuang Sampah Terhadap Kualitas Air Anak Sungai Kahayan Mendawai 7 Ujung Kota Palangka Raya

Settlements that develop around rivers will result in problems with the disposal of household waste to the riverbanks. There is quite a lot of household waste that enters the river. This study aims to determine the pollution index of the tributaries of the Kahayan Mendawai 7 Palangka Raya River to the fish in the river. The analysis was carried out using water quality analysis based on the MPN (Most Probable Number) Coliform, consisting of three test stages, namely an estimation test using Lactose Broth (KL) medium, a confirmation test using Brilliant Green Lactose Broth (BGLBB) medium, and a certainty test. using Mac Concey Agar (MCA) medium. This type of research is a direct survey method and laboratory analysis. this research was carried out in October 2021. The results of this study were obtained based on the formula and table of MPN values, three series of tubes were obtained with the total MPN Cokiform value in the estimating test of 2,400 cells/100 ml sample, the MPN value confirming test 28 cells/100 ml sample, and the number of Escherichia coli colonies in the certainty test were 69 colonies, so the water quality of the tributary of the Kahayan Mendawai 7 Ujung City of Palangka Raya was in the category of polluted and unfit for consumption.Keywords: Household Waste, Water Quality

Versatile Medium for the Isolation of Sulfur-Reducing Bacteria from Natural Ecotypes

Sulfate-reducing bacteria (SRB) are a diverse group of microorganisms that are commonly isolated from anoxygenic environments (lake depths, soil, or swamps) and are also found in the intestines of humans and animals. They are well known for outcompeting methanogens for common substrates thereby helping in the decrease of methane emissions and also playing a major role in sulfur cycling. Therefore, determining the cultivable methods for their isolation is important. Various media has been used for the cultivation and purification of SRB from natural wetlands. The luxuriant growth of SRB was observed in all the media tested, out of which the best suitable media to recover a maximum of colonies from the natural soil/sediment samples was discovered as a modified postage medium. The enumeration of the isolated SRB was done by the most probable number (MPN) technique. A total of twenty pure isolates of SRB were isolated from different ecotypes.

Assessment of Coliform, Escherichia coli, and Enterococci in Raw and Treated Water in Negeri Sembilan, and Factors Associated with the Decontamination Procedure

World Health Organization estimated that half of the world’s population will encounter water-stressed living areas by the year 2025 due to climate change, population growth, and urbanization which already pose challenges for water supply systems. In Malaysia, water operators for each state are responsible to treat water and supplying it all over the state. This study focused on Negeri Sembilan state which has 21 water treatment plants that are responsible for supplying treated water to consumers. The objectives of this study were to assess microbial contaminants in raw and treated water using a rapid detection method (IDEXX Colilert method for coliform and E. coli detection, and IDEXX Enterolert-DW for enterococci detection in drinking water) and to quantify the number of microorganism with most probable number (MPN) method. A total of 96 samples were collected from both raw (n=17) and treated water (n=79) in Negeri Sembilan. Results have shown that the raw water sample in Seremban recorded the highest number of coliform (7258.8 MPN/100 ml), E. coli (5198.7 MPN/100 ml), and enterococci (997.5 MPN/100 ml). For treated water, all samples were recorded at &lt;1 MPN/100 ml. This showed that the decontamination procedure especially chlorination done by the water treatment plant did reduce the number of microbes in drinking water. Further analysis showed that the level of ammonia did not influence the number of microorganisms. However, the presence of chlorine did reduce the number of microbes, whereas and high level of turbidity showed a high number of microbes. In conclusion, despite the high number of microbes in raw water samples, treatment using chlorine (0.2mg/L to 5.0mg/L) was effective in reducing their numbers (&lt;1 MPN/100 ml) to provide clean water to the consumers.