Sabina Fijan

Microorganisms with Claimed Probiotic Properties: An Overview of Recent Literature

Probiotics are defined as live microorganisms, which when administered in adequate amounts, confer a health benefit on the host. Health benefits have mainly been demonstrated for specific probiotic strains of the following genera: Lactobacillus, Bifidobacterium, Saccharomyces, Enterococcus, Streptococcus, Pediococcus, Leuconostoc, Bacillus, Escherichia coli. The human microbiota is getting a lot of attention today and research has already demonstrated that alteration of this microbiota may have far-reaching consequences. One of the possible routes for correcting dysbiosis is by consuming probiotics. The credibility of specific health claims of probiotics and their safety must be established through science-based clinical studies. This overview summarizes the most commonly used probiotic microorganisms and their demonstrated health claims. As probiotic properties have been shown to be strain specific, accurate identification of particular strains is also very important. On the other hand, it is also demonstrated that the use of various probiotics for immunocompromised patients or patients with a leaky gut has also yielded infections, sepsis, fungemia, bacteraemia. Although the vast majority of probiotics that are used today are generally regarded as safe and beneficial for healthy individuals, caution in selecting and monitoring of probiotics for patients is needed and complete consideration of risk-benefit ratio before prescribing is recommended.

Hospital Textiles, Are They a Possible Vehicle for Healthcare- Associated Infections?

Textiles are a common material in healthcare facilities; therefore it is important that they do not pose as a vehicle for the transfer of pathogens to patients or hospital workers. During the course of use hospital textiles become contaminated and laundering is necessary. Laundering of healthcare textiles is most commonly adequate, but in some instances, due to inappropriate disinfection or subsequent recontamination, the textiles may become a contaminated inanimate surface with the possibility to transfer pathogens. In this review we searched the published literature in order to answer four review questions: (1) Are there any reports on the survival of microorganisms on hospital textiles after laundering? (2) Are there any reports that indicate the presence of microorganisms on hospital textiles during use? (3) Are there any reports that microorganisms on textiles are a possible source infection of patients? (4) Are there any reports that microorganisms on textiles are a possible source infection for healthcare workers?

Hygiene monitoring of textiles used in the food industry

Protective clothing is required in the food-processing industry, to protect workers from contamination by bacteria, fungi, viruses, prions etc. contained in the secretions and raw meat of slaughtered animals, and to protect the meat from being contaminated by microorganisms carried by the workers. It is well-understood that textiles are a control point (CP), and must be appropriately cleaned and disinfected in order to prevent biocontamination. Although the laundering procedure itself is important for achieving disinfection, it is also essential to maintain an appropriate hygiene level in the laundry, in order to prevent recontamination of textiles by environmental viable microorganisms. In this study, a sanitary-microbiological analysis was carried out in selected CPs in two laundries. Chemo-thermal washing efficiency was determined by evaluating the anti-bacterial effect against Enterococcus faecium and Staphylococcus aureus. The hygienic state of the laundries was determined by evaluating the number and type of microorganisms at selected CPs throughout the whole laundering procedure. The results indicated that the sanitary condition of both laundries did not reach the required levels and that several microbes were resistant to cleaning and disinfecting agents. It is obvious from the results that achievement of an appropriate hygiene level during laundering textiles from the food processing industry requires the implementation of appropriate corrective monitoring measures.

The Influence of Industrial Laundering of Hospital Textiles on the Properties of Cotton Fabrics

Every laundry is determined to maintain or constantly improve the quality of its services. This quality is defined by parameters that are determined by standard methods. With the help of different industrial laundries some research on the influence of laundering procedure on the quality of laundered fabrics was conducted. For this purpose standard cotton fabrics were laundered 50 times or 25 times, respectively, by certain procedures. After laundering, the quality was assessed by determining the decrease in breaking strength, chemical wear, incineration residue, Ganz degree of whiteness, lightness and the Ganz—Griesser tint deviation. It was found that higher chemical and mechanical damage was mainly due to higher concentrations of hydrogen peroxide used at higher temperatures in longer laundering procedures with lower bath ratios. The quality of the investigated laundering procedures could be improved by adapting the dose of detergents, bath ratio, temperature and duration as well as the sorting before laundering.

Efficiency of four sampling methods used to detect two common nosocomial pathogens on textiles

Detecting microorganisms on textiles is useful for many purposes, for example to determine the bioburden before laundering, assess the reduction in bacterial counts in connection with various laundry processes, or trace transfer routes in infection control investigations. Therefore a validated, reproducible and rational method is needed. For sampling microorganisms on textile surfaces the most commonly used method is the contact plate method using RODAC plates, first described by Hall and Hartnett followed by the swab sampling technique. Both methods can only capture microorganisms on the surface of the textiles while microorganisms that have penetrated into the deeper structure of the material will not be detected. In our research the contact plate method and the swabbing technique were compared with two wash-off methods. For the first wash-off method the destructive elution method was used, where microorganisms were eluted from the fabrics by shaking the fabrics for a certain time in an elution medium. For the fourth sampling method a nondestructive method that included a compact test device called Morapex® was used, which is based on forced desorption by pressing the microorganisms through the fabric without destroying the fabric. In our research, two types of microorganisms were included (Klebsiella pneumoniae and Staphylococcus aureus) that cause common nosocomial infections. The aim of this study was to compare the efficiency of the four sampling methods for detecting microorganisms on textiles and to determine the lowest concentration, which can still be detected. The percentage of microorganisms that were detected by both elution methods was substantially higher than by sampling of fabrics with the contact plate method or swabbing. It can be concluded that a nondestructive method using a modified Morapex® device can be applied for quick determination of the hygienic condition of textiles.

Influence of the Growth of Pseudomonas aeruginosa in Milk Fermented by Multispecies Probiotics and Kefir Microbiota

Introduction: Probiotics are defined as live microorganisms, which when administered in adequate amounts, confer a health benefit on the host. Health benefits have mainly been demonstrated for specific probiotic strains of the following genera: Lactobacillus, Bifidobacterium, Saccharomyces, Enterococcus, Streptococcus, Pediococcus, Leuconostoc and Bacillus. The human microbiota is getting a lot of attention today and research has already demonstrated that alteration of this microbiota may have far-reaching consequences. One of the possible routes for correcting dysbiosis is by consuming probiotics. Methods: In this research we investigated the influence of potentially pathogenic challenge bacteria Pseudomonas aeruginosa on multispecies probiotic food supplement and kefir microbiota. The probiotics included various strains of the species Lactobacillus acidophilus, Lactobacillus reuteri, Lactobacillus rhamnosus, Lactobacillus delbrueckii subs, bulgaricus, Lactobacillus plantarum, Lactobacillus lactis subs, lactis, Bifidobacterium bifidum, Bifidobacterium breve, Bifidobacterium longum, Streptococcus thermophilus, Enterococcus faecium. Samples of 40 mL of milk were prepared with added challenge potentially pathogenic Pseudomonas aeruginosa and 1 mL suspension of multispecies probiotics. All samples were incubated for 4 days. Results and discussion: It was found that both the multispecies probiotic supplement and the kefir microbiota with diverse microbial populations successfully decreased the concentration of challenge potentially pathogenic Pseudomonas aeruginosa for 3 log10 steps. On the other hand the antagonistic effect of the oligospecies probiotics with only three different probiotic species and the monospecies probiotic supplement against P. aeruginosa was not detected. These results show that multispecies microorganisms that create a live communities create a synergistic effect and effective complex interconnecting quorum-sensing regulatory networks that compete with a potentially pathogen bacteria. Conclusions: Although probiotic administration does not permanently modulate the intestinal microbiota, this does not mean that during acute disruption of the sensitive intestinal microbiota balance such as due to antibiotic consumption, transiently present probiotics do not aid the permanent intestinal microbiota in restoring this balance.

Determining the disinfection of textiles in compressed carbon dioxide using various indicator microbes

Aims:  This paper presents a research on the disinfection efficiency of inoculated textile swatches by compressed carbon dioxide, an environmental friendly way to disinfect textiles as opposed to the conventional laundering procedures using water. The disinfection efficiency was determined by using the following microbes inoculated on cotton test fabrics: Enterococcus faecium, Enterobacter aerogenes and Candida albicans.

Survival of Enterococcus faecium, Staphylococcus aureus and Pseudomonas aeruginosa on cotton:

The aim of this study was to evaluate the survival of three challenge bacteria stored at 25℃, 5℃, and 50℃ up to 21 days on 100% cotton textile swatches. The survival of each chosen challenge bacteria was determined by the classical phenotype colony counting method through growth on selective media, and the molecular method of detecting Staphylococcus aureus-, Enterococcus faecium-, and Pseudomonas aeruginosa-specific DNA. E. faecium proved to be the most persistent chosen challenge bacteria at all three chosen storage temperatures. Both E. faecium and S. aureus survived on textile swatches up to 21 days at 25℃ at the highest inoculum. E. faecium and P. aeruginosa persisted at 50℃ only up to 9 and 3 days, respectively. All challenge bacteria survived on textile swatches at 5℃ (E. faecium 12 days, P. aeruginosa and S. aureus less than 6 days). The results of survival at lower initial inoculum were lower and less dependent on temperature. Dehydration phenomena or fluctuation in relative humidity in the refrigerator at 5℃ possibly explains lower survival than at room temperature. Positive results for the detection of E. faecium- and P. aeruginosa-specific DNA were found for some samples with negative results for classical phenotype counting methods, perhaps owing to the fact that the bacterial cells, due to adverse environmental conditions, reached a viable, but noncultivable (VBNC) state, or that the extracellular DNA fragments persisted on the textiles. Survival of the challenge bacteria for more than 3 days regardless of temperature proves that hospital textiles as an inanimate surface should not be neglected as one of the possible vectors for transmission of pathogens causing healthcare associated infections.

Real-time polymerase chain reaction for quantitative assessment of common pathogens associated with healthcare-acquired infections on hospital textiles

A hospital environment may act as a significant reservoir for potential pathogens that can be transmitted with hospital textiles, which could represent a source of healthcare-acquired infections. Quantitative assessment of nosocomial pathogens with real time polymerase chain reaction (qPCR) on textiles can serve to verify the achievement of standards for textile hygiene of hospital laundry that assess the risk for acquiring hospital infection from inappropriately disinfected textiles. The aim of the study was to establish qPCR for quantitative assessment of selected common nosocomial pathogens (Clostridium difficile, Staphylococcus aureus, Klebsiella pneumoniae and Pseudomonas aeruginosa) on hospital textiles and to compare the efficiency of the molecular method to the standard procedures for evaluating the bio burden of textiles in hospitals. This study demonstrated that presence of nosocomial pathogens on hospital textiles can be confirmed with qPCR even where conventional techniques do not give any results. qPCR offers a possibility to confirm the presence of microorganisms in dead or viable but non-culturable states that cannot be detected by conventional sampling techniques but may still pose a hazard to public health.

Study of the In Vitro Antagonistic Activity of Various Single-Strain and Multi-Strain Probiotics against Escherichia coli

Escherichia coli is an important commensal of our gut, however, many pathogenic strains exist, causing various severe infections in the gut or beyond. Due to several antibiotic resistance patterns of E. coli, research of alternative treatments or adjuvant therapy is important. One of these is the use of probiotics as antagonistic agents against E. coli. Most published studies investigate only one strain of E. coli and single-strain probiotics. The objectives of this study were to evaluate the antagonistic activity of selected single-strain and multi-strain probiotic supplements against selected clinical E. coli pathotypes using the in vitro agar spot test and the co-culturing method. Molecular methods were used to determine the presence of the genus lactobacilli and bifidobacteria as well as certain selected strains in the probiotic supplements. The agar-spot test showed that the multi-strain probiotics were more effective than the single-strain probiotics. On the other hand, the co-culturing method showed the opposite result, indicating that results are importantly influenced by the chosen method. The most effective single-strain probiotics against E. coli strains were Bifidobacterium animalis subsp. lactis BB-12 and Lactobacillus reuteri DSM 17938. The most effective multi-strain probiotics contained lactobacilli, bifidobacteria and enterococci strains, thus proving that most effective probiotics against E. coli strains are the lactic acid bacteria and bifidobacteria. The overall results from both in vitro tests reveal that all selected probiotics exhibited an antagonistic activity against all E. coli strains. From a public health perspective probiotics have thus proved to be successful in inhibiting the growth of E. coli and could therefore be used as adjuvant therapy or alternative therapy in E. coli infections.