Heavy metal tolerance patterns of total heterotrophic bacteria isolated from the soils of Mahatma Gandhi University campus, Kottayam, Kerala

Industrialization of our society has led to an increased production and discharge of both xenobiotic and natural chemical substances. Many of these chemicals will end up in the soil. Pollution of soils with heavy metals is becoming one of the most severe ecological and human health hazards. Elevated levels of heavy metals decrease soil microbial activity and bacteria need to develop different mechanisms to confer resistances to these heavy metals. Bacteria develop heavy-metal resistance mostly for their survivals, especially a significant portion of the resistant phenomena was found in the environmental strains. Therefore, in the present work, we check the multiple metal tolerance patterns of bacterial strains isolated from the soils of MG University campus, Kottayam. A total of 46 bacterial strains were isolated from different locations of the campus and tested for their resistant to 5 common metals in use (lead, zinc, copper, cadmium and nickel) by agar dilution method. The results of the present work revealed that there was a spatial variation of bacterial metal resistance in the soils of MG University campus, this may be due to the difference in metal contamination in different sampling location. All of the isolates showed resistance to one or more heavy metals selected. Tolerance to lead was relatively high followed by zinc, nickel, copper and cadmium. About 33% of the isolates showed very high tolerance (>4000μg/ml) to lead. Tolerance to cadmium (65%) was rather low (<100 μg/ml). Resistance to zinc was in between 100μg/ml - 1000μg/ml and the majority of them shows resistance in between 200μg/ml - 500μg/ml. Nickel resistance was in between 100μg/ml - 1000μg/ml and a good number of them shows resistance in between 300μg/ml - 400μg/ml. Resistance to copper was in between <100μg/ml - 500μg/ml and most of them showed resistance in between 300μg/ml - 400μg/ml. From the results of this study, it was concluded that heavy metal-resistant bacteria are widely distributed in the soils of MG university campus and the tolerance of heavy metals varied among bacteria and between locations

Removal of total coliforms, thermotolerant coliforms, and helminth eggs in Swine production wastewater treated in anaerobic and aerobic reactors

The present work evaluated the performance of two treatment systems in reducing indicators of biological contamination in swine production wastewater. System I consisted of two upflow anaerobic sludge blanket (UASB) reactors, with 510 and 209 L in volume, being serially arranged. System II consisted of a UASB reactor, anaerobic filter, trickling filter, and decanter, being also organized in series, with volumes of 300, 190, 250, and 150 L, respectively. Hydraulic retention times (HRT) applied in the first UASB reactors were 40, 30, 20, and 11 h in systems I and II. The average removal efficiencies of total and thermotolerant coliforms in system I were 92.92% to 99.50% and 94.29% to 99.56%, respectively, and increased in system II to 99.45% to 99.91% and 99.52% to 99.93%, respectively. Average removal rates of helminth eggs in system I were 96.44% to 99.11%, reaching 100% as in system II. In reactor sludge, the counts of total and thermotolerant coliforms ranged between 10(5) and 10(9) MPN (100 mL)(-1), while helminth eggs ranged from 0.86 to 9.27 eggs g(-1) TS.

Avaliação da eficiência de métodos rápidos usados para detecção de coliforme totais e coliforme fecais em amostras de água, em comparação com a técnica de fermentação em tubos múltiplos

Pós-graduação em Alimentos e Nutrição - FCFAR

Evaluation of the use of probiotic acid lactic bacteria in the development of chicken hambúrguer

The objective of this study was to investigate the effect of fermentation with Lactobacillus acidophilus CRL 1014 on the physicochemical, microbiological and sensory characteristics of a hamburger product like processed with chicken meat and okara flour, with reduction of curing salts. A mixture of ingredients containing 90% chicken meat and 10% okara flour was subjected to the following treatments: F1: fermented with Lactobacillus acidophilus; F2:75 mg nitrite/kg and fermented with Lactobacillus acidophilus; F3: 150 mg nitrite/kg and unfermented. The quality of the “hamburgers” was assessed by physical and chemical analysis (pH, cooking yield and shrinkage), chemical composition, microbiological tests (Salmonella spp., count of sulphite-reducing clostridia, staphylococos coagulase-positive, total coliforms and Escherichia coli) and sensory analysis (sensory acceptance and purchase intent). During the first six days of fermentation, there was a decrease in pH from approximately 6.33 to 5.10. All the samples showed the same chemical composition (p < 0.05). The fermentation process was observed to inhibit the multiplication of microorganisms of several groups: coagulasepositive staphylococci, sulphite-reducing clostridia, Salmonella spp. and E. coli. The different “hamburgers” formulations showed high scores for all the sensory attributes evaluated, without differing from each other (p < 0.05). The results showed that the use of L. acidophilus CRL 1014 enabled the production of a safe product, with good physicochemical and sensory characteristics, in the absence of curing salts.

Fecal indicators and bacterial pathogens in bottled water from Dhaka, Bangladesh

Forty-six bottled water samples representing 16 brands from Dhaka, Bangladesh were tested for the numbers of total coliforms, fecal indicator bacteria (i.e., thermotolerant Escherichia coli and Enterococcus spp.) and potential bacterial pathogens (i.e., Aeromonas hydrophil, Pseudomonas aeruginos, Salmonella spp., and Shigella spp.). Among the 16 brands tested, 14 (86%), ten (63%) and seven (44%) were positive for total coliforms, E. coil and Enterococcus spp., respectively. Additionally, a further nine (56%), eight (50%), six (37%), and four (25%) brands were PCR positive for A. hydrophila lip, P. aeruginosa ETA, Salmonella spp. invA, and Shigella spp. ipaH genes, respectively. The numbers of bacterial pathogens in bottled water samples ranged from 28 ± 12 to 600 ± 45 (A. hydrophila lip gene), 180 ± 40 to 900 ± 200 (Salmonella spp. invA gene), 180 ± 40 to 1,300 ± 400 (P. aeruginosa ETA gene) genomic units per L of water. Shigella spp. ipaH gene was not quantifiable. Discrepancies were observed in terms of the occurrence of fecal indicators and bacterial pathogens. No correlations were observed between fecal indicators numbers and presence/absence of A. hydrophila lip (p = 0.245), Salmonella spp. invA (p = 0.433), Shigella spp. ipaH gene (p = 0.078), and P. aeruginosa ETA (p = 0.059) genes. Our results suggest that microbiological quality of bottled waters sold in Dhaka, Bangladesh is highly variable. To protect public health, stringent quality control is recommended for the bottled water industry in Bangladesh. Key words: bottled water, fecal indicator bacteria, quantitative PCR, bacterial pathogens, public health risk.

Bioaerosols associated with industrial green waste composting facilities and optimal microbiological indicators

This project developed and assessed a standard operating procedure for monitoring microbiological aerosol levels and dispersal from Australian industrial composting facilities. Development occurred via seasonal monitoring of such operations with evaluation of optimal microbial indicator organisms, sampling and analysis logistics. The resultant procedure allows practical end-user assessment of compost-associated bioaerosol levels, and potential health risks to proximal residential populations encroaching on such composting facilities and on-site industrial operations personnel.

La pollution bacterienne de la lagune et de la mer autour d'Abidjan

The total coliforms, fecal coliforms and fecal streptococci were counted over 1 year at 33 stations in the Ebrié Lagoon near Abidjan (Ivory Coast). Most of the waters show high numbers of bacteria, (D category of the American standards). For the sea-beaches, high numbers of fecal germs are found where the human population is abundant.

Incidence of human pathogenic bacteria in shrimp feeds - a study from India

The incidence of various human pathogenic bacteria in commercially available and home-made shrimp feeds used on some farms in India was analyzed. The Total Heterotrophic Bacteria in the commercial feed samples ranged between 103–105 cfu g-1 and those in the farm-made feeds between 106-107 cfu g-1. No bacteria of significance to human health were found to be associated with any of the commercial feed samples analyzed, while farm-made feeds analyzed during the study showed a high incidence of various human pathogens such as Vibrio parahaemolyticus, V. cholerae, Escherichia coli and Staphylococcus aureus. Possible modes of contamination in feeds and ways to prevent them are discussed.

Nitrogen fixing bacteria, Azotobacter sp. in aquatic sediment

Non-symbiotic, free living, nitrogen fixing bacteria, Azotobacter sp. was estimated in sediments of estuarine, marine, backwater and mangrove environments of Portonovo. Number of colony forming units (CFU) of Azotobacter sp. was less (5 to 27 cells/g of dry sediment). CFU of total heterotrophic bacteria (THB), actinomycetes and fungi were between 4.1x10 super(6) and 4.5x10 super (7), 0.8x10 super(5) and 4.9x10 super(5), 1.1x10 super(5) and 3.8x10 super(5)/g respectively. Mangrove sediments contained more CFU of the above microbial groups.

Studies on lipolytic bacteria in stored fish Etroplus suratensis (Bloch)

The distribution of total hectrotrophic bacteria (THB) and lipolytic bacteria in various regions (body surface, gill, intestine and flesh) of fish Etroplus suratensis (Bloch) during storage at 28 ± 2°C and 4°C was studied. Pseudomonas dominated at reduced temperature whereas at 28 ± 2°C and in fresh condition Vibrio, Aeromonas, and Acinetobacter dominated. Lipolytic activity was elaborated by the members of various genera and their activity varied in different lipid compounds (tributyrin, tween 80, tween 60, tween 40 and tween 20). Tributyrin was utilized by majority of the isolates. All the selected isolates preferred a temperature of 35°C and pH 6.0 for their maximum growth. Aeromonas and Vibrio showed maximum growth at 0.5% NaCl concentration while 3% NaCl was found to be optimum for Pseudomonas.

Studies on the bacteria associated with Penaeus indicus in a culture system

Ocean persists as a rich and renewable source of cheap protein for the whole world. Among the prawns/shrimps landed from the Indian Ocean and her backwaters, more than 90% are exported to affluent countries. The Indian white prawn Penaeus indicus, constitutes the major portion of the frozen shrimps exported from India every year. The present study is aimed at gathering information on the total heterotrophic bacteria (THB) associated with B. indicus, with special reference to eggs, nauplii, zoeae, mysis, and post larvae in hatchery, and juveniles and adults in culture pond. Simultaneously, IHB associated with E. indicus in its natural habitat also is studied for comparison. It is envisaged that this information will be highly useful for modifying the existing hatchery and pond management-practices.

‘Studies on Bacterial Indicators and Pathogen Vibrio parahaemolyticus in Cochin Backwater

Microbiological studies on the incidence, behaviour, activity and ecological implications of marine micro~organisms, particularly microbial pathogens in coastal waters and estuaries exhibit the increasing concern and awareness of environmental impacts on health and wealth. Marine microbiologists have been active in investigating on the distribution, kinds of organisms and their activity in the environment. However, informations on the effect of environment on the ecology or on the distribution (spatial/temporal) of microbial comunity and competition among groups inhabiting the ecosystem are sparE§L Estuarine environment are complex with respect to diversity of habitats, variation in physicochemical parameters and contamination by terrestrial bacterial species. Being the organisms of‘public health significance, ecological studies on total coliforms, faecal coliforms, faecal streptococci, §. ggli and X. parahaemolyticus have great relevance as studies of these types would provide a wealth of information to environmentalists and to fishery industry. In order to evalé%e the status, role and significance of potentially hazardous bacterial species in natural environment it is necessary to monitor the ecology of such organisms systematically in relation to physico-chemical parameters

Heterotrophic bacteria from the continental slope sediments of arabian sea

The marine environment is indubitably the largest contiguous habitat on Earth. Because of its vast volume and area, the influence of the world ocean on global climate is profound and plays an important role in human welfare and destiny. The marine environment encompasses several habitats, from the sea surface layer down through the bulk water column, which extends >10,000 meters depth, and further down to the habitats on and under the sea floor. Compared to surface habitats, which have relatively high kinetic energy, deep-ocean circulation is very sluggish. By comparison, life in the deep sea is characterized by a relatively constant physical and chemical environment. Deep water occupying the world ocean basin is a potential natural resource based on its properties such as low temperature, high pressure and relatively unexplored properties. So, a judicious assessment of the marine resources and its management are essential to ensure sustainable development of the country’s ocean resources. Marine sediments are complex environments that are affected by both physiological and biological factors, water movements and burrowing animals. They encompass a large extent of aggregates falling from the surface waters. In aquatic ecosystems, the flux of organic matter to the bottom sediments depend on primary productivity at the ocean surface and water depth. Over 50% of the earth’s surface is covered by deep-sea sediments that are primarily formed through the continual deposition of particles from the productive pelagic waters (Vetriani et al., 1999). These aggregates are regarded as ‘hot spots’ of microbial activity in the ocean (Simon et al., 2002). This represents a good nutritional substrate for heterotrophic bacteria and favours bacterial growth

Microbiology quality in continuous water flow fish ponds

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Honey consumption in the state of São Paulo: a risk to human health?

Infantile botulism was recognized in 1976 as a paralyzing disease caused by the ingestion of viable spores that would germinate and colonize the intestinal tract of infants, with local production and absorption of Clostridium botulinum toxin. The possible origins of botulinic spores are dust and honey, which has been identified as a dietary risk factor for infantile botulism. The objectives of the present study were to investigate 100 honey samples obtained in the state of São Paulo (Brazil) in terms of incidence of botulinic spores and of microbiologic quality, in agreement with Decree 367/9. All 100 samples analysed were negative for the presence of Salmonella, Shigella, total coliforms. C botulinum spores were present in 3 samples (3%) and molds and yeasts, in 64 samples (64%), but only 25 (25%) exceeded established criteria, with counts ranging from zero to 1.5 x 10(5) CFU/g. The presence of small sporogenic Gram-positive rods was observed in 42 (42%) of the 100 samples tested but these bacteria were not identified. (C) 2003 Elsevier Ltd. All rights reserved.