Bacterial contaminants associated with automated teller machines (ATMS) keypads in Lafia Metropolis, Nasarawa State, Nigeria

No Abstract.

Endophytic Bacteria in Banana In Vitro Cultures: Molecular Identification, Antibiotic Susceptibility, and Plant Survival

Microbial contamination is a common problem that causes significant losses in plant micropropagation systems. The present study reports on the identification and control of bacterial contaminants in banana in vitro cultures. Twelve isolates belonging to Bacillus pumilus (S2), Bacillus subtilis (R2 and M4), Geobacillus stearothermophilus (S1, S3, S4, P2, M3 and R3) and Paenibacillus spp. (P1, R1 and M2) were identified by sequencing of 16S rRNA, gyrA or gyrB genes. Antibiotic susceptibility testing was performed with the disk diffusion method on bacterial isolates using 36 antimicrobial agents. Some antibiotics, notably Ticarcillin, Penicillin, Ampicillin, Cefazolin and Imipenem, had a broader range of bactericidal activity than others did. When contaminated axillary shoot cultures of banana were treated with 100 or 200 mg·L−1 of ticarcillin, ampicillin or penicillin the bacteria were eliminated, but a reduction in shoot multiplication and growth was observed. These findings contribute to minimizing the losses in the commercial micropropagation of banana.

Naira note: Potential Environmental Material for Transmitting Bacterial Pathogens among Food Dealers in Umuahia, Nigeria

Inanimate objects can serve as environmental vehicles for transmitting pathogenic bacteria among individuals in the population. Our study revealed that of the 72 naira notes examined, 58 samples representing 80.6% had bacterial contaminants. The bacterial isolates were Staphylococcus aureus (70.8%), Salmonella spp. (51.4%), Escherichia coli (44.4%), Shigella spp. (22.2%), Pseudomonas aeruginosa. (18.1%), and Proteus spp. (1.4%). The naira notes examined were all obtained from food dealers particularly fish sellers, food vendors, and meat sellers. The presence of these bacterial pathogens on naira notes handled by those food dealers is an important public health hazard as they can contaminate food leading to foodborne diseases and intoxications. Our study found that lower denominations of currency notes (naira), were mostly contaminated by these pathogens and this could be as a result of their frequent use in daily transactions.

EFFECT OF PENICILLIN -CIPROFLOXACIN COMBINATION ON SEMEN CHARACTERISTIC AND BACTERIAL CONTAMINANTS OF DILUTED BULL SEMEN

Effect of penicillin- ciprofloxacin combinations on some semen characteristics and bacterial contaminants of diluted bull semen was determined and compared with those of penicillin- streptomycin combinations. Sperm motility, percentage of dead and abnormal spermatozoa and survival index did not differ significantly for penicillin (1000 IU) and ciprofloxacin (125, 250, 500, 1000 ug) combinations per milliliter of diluted bull semen from those of penicillin (1000 I.U) and streptomycin (500 ug) combination / ml. Each penicillin ciprofloxacin combination effectively controlled bacterial growth. However penicillin streptomycin combination did not effectively control the growth. Accordingly, the combination of penicillin- ciprofloxacin seems to be a satisfactory substituent for penicillin- streptomycin combination for controlling bacterial contaminants in diluted bull semen without impairing semen characteristics.

Technical challenges regarding the use of formalin-fixed paraffin embedded (FFPE) tissue specimens for the detection of bacterial alterations in colorectal cancer

Background Formalin-fixed paraffin embedded (FFPE) tissues may provide an exciting resource to study microbial associations in human disease, but the use of these low biomass specimens remains challenging. We aimed to reduce unintentional bacterial interference in molecular analysis of FFPE tissues and investigated the feasibility of conducting quantitative polymerase chain reaction (qPCR) and 16S rRNA amplicon sequencing using 14 colorectal cancer, 14 normal adjacent and 13 healthy control tissues. Results Bacterial contaminants from the laboratory environment and the co-extraction of human DNA can affect bacterial analysis. The application of undiluted template improves bacterial DNA amplification, allowing the detection of specific bacterial markers (Escherichia coli and Faecalibacterium prausnitzii) by qPCR. Nested and non-nested PCR-based 16S rRNA amplicon sequencing approaches were employed, showing that bacterial communities of tissues and paired paraffin controls cluster separately at genus level on weighted Unifrac in both non-nested (R2 = 0.045; Pr(> F) = 0.053) and nested (R2 = 0.299; Pr(> F) = 0.001) PCR datasets. Nevertheless, considerable overlap of bacterial genera within tissues was seen with paraffin, DNA extraction negatives (non-nested PCR) or PCR negatives (nested PCR). Following mathematical decontamination, no differences in α- and β diversity were found between tumor, normal adjacent and control tissues. Conclusions Bacterial marker analysis by qPCR seems feasible using non-normalized template, but 16S rRNA amplicon sequencing remains challenging. Critical evaluation of laboratory procedures and incorporation of positive and negative controls for bacterial analysis of FFPE tissues are essential for quality control and to account for bacterial contaminants.

Influence of Simplified Microbial Community Biofilms on Bacterial Retention in Porous Media under Conditions of Stormwater Biofiltration

The retention efficiency of bacterial contaminants in biofilm-colonized biofilters is highly variable. Despite the increasing number of studies on the impact of biofilms in filters on bacterial retention, how individual bacterial strains within a biofilm community combine to influence bacterial retention is unknown.

Quantitative Measurement of Enteric Bacteria Load From Public Surfaces in Restaurants in Nnewi-Town

Background: Bio-contamination of surfaces of various items and equipment used by the public is the main cause of disease epidemic. Most outbreaks of infection associated with inanimate objects are caused by items that should be sterile but have been contaminated and are generally known as fomites. Objective: This study is to evaluate the presence of enteric bacteria from different public surfaces in restaurants in Nnewi town. Methodology: Selected public surfaces in eight (8) randomly selected restaurants were analyzed for the presence of enteric bacteria via culture and biochemical tests following a standard criterion. The sample sites included; tables, chairs, counters, sinks and walls. Also, Disc susceptibility test were carried out on the isolates using conventional antibiotics. Results: Eighty-eight (88) bacteria isolates were isolated and identified, and S. aureus showed the highest prevlence 29(33%), followed by E. coli 15(17%), Proteus spp 13(15%), Klebsiella spp 12(14%), Pseudomonas spp 10(11%), and Coagulase-negative Staphylococci 9(10%). Tables and sinks were the most contaminated fomites each constituting of 19(22%) of the total bacteria isolated in this study. Escherichia coli, Pseudomonas spp, Proteus spp and Staphylococcus aureus, were the most resistant isolates to the antibiotics, Coagulase-negative Staphylococci was the most sensitive isolate. Out of the ten antibiotics tested ceporex was found to be the least effective with about 100% resistance by the isolates while ciprofloxacin, ceftriaxone, and levofloxacin were the most effective antibiotics with 0% resistance by the bacteria isolates. Conclusion: the study has shown that public surfaces in restaurant can easily be contaminated with a variety of bacterial contaminants that may be multi-drug resistant bacteria strains posing as a possible public health issue.

Profiling of essential mineral content, heavy metals, and bacterial contaminants in conventional and organic eggs available in the hypermarkets of the Eastern Province of Saudi Arabia

Background: Eggs are commonly regarded as one of the best sources of various macro, and micronutrients, in particular, high biological value (BV) proteins, and both saturated, and unsaturated fatty acids. Apart from proteins, eggs are excellent sources of various high health value lipid components, carotenoids, minerals, and both water and lipid-soluble vitamins. However, the nutrient-rich nature of this ‘superfood’ also makes them susceptible to microbial contamination from various sources, such as fecal matter, drinking water for layer chicken, and the surrounding environment. Moreover, drinking water and chicken feed are also sources of heavy metal contamination. The presence of both factors poses serious health concerns for consumers. Objective: The main aim of this research was to proximate heavy metals and bacterial contaminants in nine different brands of brown organic and white conventional eggs available in the hypermarkets of the Eastern Province of Saudi Arabia. Methods: An Inductively Coupled Plasma-Optical Emission Spectrometer (ICP-OES), was used to determine the concentration of metals with high sensitivity. Standard plate count eas followed by enrichment of bacterial contaminants in a double-strength nutrient broth medium for microbiological assessment. Results: The results indicated that Pb, Cd, Al, and As were present in high concentrations in all egg brands of both types (organic and conventional). The estimated daily intake (EDI) values for Ca, Fe, Mn, and Mg were within the range of WHO-recommended thresholds, and that these essential minerals were present in adequate amounts in all egg brands. The two major groups predominating the microbial loads were the family Enterobacteriaceae and Pseudomonas sp. Conclusion: The presence of heavy metals, such as Al, As, Pb, and Cd, in nearly all the brands, amounts that exceeded the established ADI and EDI thresholds were a considerable concern. In particular, the elevated levels of Cd and Pb, group 1 and group 2A probable human carcinogens respectively, demands that local regulatory authorities investigate the sources of heavy metal contamination, and alleviate this considerable risk to human health. Furthermore, this study could be a benchmark for establishing food safety and hygiene standards for local egg production, storage, handling, and transport in Saudi Arabia.

Detection of Bacterial Pathogens in Ready-To-Eat Foods: Potential Public Health Hazard

The right to obtain safe food is one of the most vital and fundamental human rights that must not be compromised or neglected; this is important because foodborne diseases can lead to prolonged disability and even death. Our study examined 28 samples of ready-to-eat foods, of which 27 samples (96.4%), contained bacterial contaminants. The bacterial pathogens isolated include Escherichia coli (50%), Salmonella spp (75%) and Staphylococcus aureus (85.7%). All the samples of jollof rice (100%), bean porride (100%) and eba (100%) were contaminated while 85.7% of egusi soup samples contained bacterial contaminants. The presence of these bacterial pathogens in the ready-to-eat foods poses huge risk to public health. It calls for immediate and sustainable action to prevent the possibility of foodborne disease out-break and intoxication capable of harming public health and socio-economic development.