Enterobacter gergoviaeadaptation to preservatives commonly used in cosmetic industry

A loophole in soap dispensers mediates contamination with Gram-negative bacteria

Liquid soap dispensers are widely used in domestic and clinical settings. In previous studies, the risk of bacterial contamination of refillable systems was pointed out and a bacterial contamination rate of 25%, with values of up to 108  colony-forming units/mL (CFU/mL), was reported. However, the route of contamination remains elusive. To address this point, we determined the microbial contamination of refillable standard pump dispensers and nonrefillable press-dispenser systems. Following the collection of 104 liquid soap dispensers from hotel rooms across Germany, bacterial counts were determined. Isolates of samples containing nonfastidious Gram-negative(lac-) bacteria were further analyzed by the Vitek 2 system for the determination of species. 70.2% of the refillable pump dispensers (mean total bacterial count = 2.2 × 105  CFU/mL) but only 10.6% of the nonrefillable press dispensers, were contaminated (mean total bacterial count = 1.5 × 101  CFU/mL). Of samples containing nonfastidious Gram-negative(lac-) bacteria, Pluralibacter gergoviae was present in 41.7%, Pseudomonads (Pseudomonas aeruginosa and Pseudomonas putida) in 25%, Serratia marcescens in 16.7%, and Klebsiella oxytoca and Pasteurella testudinis in 8.3%. After the initial assessment, we contaminated different dispensing systems with P. aeruginosa/P. gergoviae, to reveal the route of contamination and identied the pressure release of standard pump dispensers as the loophole for microbial contamination.

Real-time qPCR to evaluate bacterial contamination of cosmetic cream and the efficiency of protective ingredients

AIMS

The absence of objectionable micro-organisms in cosmetics and the efficiency of preservatives are still mainly assessed by time-consuming cultivation-based methods. We explored the applicability of real-time quantitative polymerase chain reaction (qPCR) and reported on the behaviour of different bacteria in artificially contaminated creams.

METHODS AND RESULTS

Real-time qPCR on DNA from Burkholderia cepacia, Pluribacter gergoviae, Pseudomonas aeruginosa and Sphingomonas paucimobilis identified specific primer pairs that amplify accurately and efficiently two strains/isolates of each species. Using DNeasy mericon Food Kit, we detected bacterial growth in an inoculated cosmetic cream and persistency of DNA from heat-inactivated bacteria. We were also able to monitor the growth inhibitory effect of caprylyl glycol and EDTA, also showing how different bacterial species interact depending on the presence/absence of these ingredients. Finally, creams supplemented with the protective cosmetic ingredients revealed the various behaviour of five strains/isolates from P. aeruginosa.

CONCLUSIONS

Successfully extracting bacterial DNA from artificially contaminated cosmetic creams, we could perform real-time qPCR to identify and follow the growth of various strains of 4 bacteria species under different conditions.

SIGNIFICANCE AND IMPACT OF THE STUDY

Real-time qPCR appears as a promising method to detect bacterial contamination in cosmetic creams and/or to monitor growth inhibition by ingredients.

In vitro study to evaluate the antimicrobial activity of various multifunctional cosmetic ingredients and chlorphenesin on bacterial species at risk in the cosmetic industry

AIMS

We evaluated the activity of the preservative chlorphenesin and of four antimicrobial cosmetic multifunctional ingredients against various strains of gram-negative and gram-positive human opportunistic pathogens.

METHODS AND RESULTS

Growth kinetics, modelling growth parameters and statistical analyses enabled comparing bacterial behaviour in the presence and in the absence of the compound. Whatever compound tested (i.e. chlorphenesin, phenylpropanol, hexanediol, ethylhexylglycerin, hydroxyacetophenone) and strain origin (i.e. clinical versus industrial), the growth of 42 strains belonging to Acinetobacter spp., Burkholderia cepacia complex and Stenotrophomonas maltophilia, was totally inhibited. On the opposite all of the P. aeruginosa strains (n = 13) as well as 4 and 6 out of 10 strains of Pluralibacter gergoviae grew in the presence of chlorphenesin and ethylhexylglycerin, respectively. Some P. gergoviae and Staphylococcus hominis strains withstand hydroxyacetophenone. Within a species, the different strains show variable latency phase, growth rate (r) and carrying capacity (K). They can be similar, lower or higher than those measured in control conditions.

CONCLUSIONS

Data showed differences in the antimicrobial activity of compounds. Upon exposure, strains differed in their behaviour between and within species. Whatever species and strains, compound sensitivity could not be related to antibiotic resistance.

SIGNIFICANCE AND IMPACT OF THE STUDY

Most multifunctional ingredients showed significant antimicrobial properties against the wide panel of species and strains evaluated. This will help adjusting preservation strategies in the cosmetic industry.

Genome Sequence of Pluralibacter gergoviae ECO77, a Multireplicon Isolate of Industrial Origin

In order to expand the limited understanding of the genomics of antimicrobial-resistant industrial bacteria, we report the genome sequence of Pluralibacter gergoviae ECO77, a historical contaminant strain of industrial origin. The multireplicon 6.16-Mbp genome of ECO77 consists of a 5.37-Mbp main chromosome, a megaplasmid (605,666 bp), and a large plasmid (182,007 bp).

In order to expand the limited understanding of the genomics of antimicrobial-resistant industrial bacteria, we report the genome sequence of Pluralibacter gergoviae ECO77, a historical contaminant strain of industrial origin. The multireplicon 6.16-Mbp genome of ECO77 consists of a 5.37-Mbp main chromosome, a megaplasmid (605,666 bp), and a large plasmid (182,007 bp).

Understanding the challenges of non-food industrial product contamination

Preventing microbial contamination of non-food products is a major area of industrial microbiology where preservatives are used to stop microbial growth. However, microorganisms occasionally overcome product preservation, causing recalls and the implementation of multiple procedures to prevent further contamination. Correct reporting of microbial contamination in non-food industrial products is vital, especially if spoilage organisms are antimicrobial resistant and pose a health threat. Gram-negative bacteria such as Pseudomonas, Burkholderia and Enterobacteriaceae are frequently reported as non-food product contaminants, including species that overlap current antimicrobial resistance priorities. Historical analysis of recall databases highlighted that for greater than 15% of contamination incidents, the causative microbial agents are reported as unidentified. Here we review the current antimicrobial resistant bacterial species associated with non-food product contamination and evaluate recall reporting in Europe from 2005 to 2018. Our review shows that 49% of microbial contaminants are reported as unidentified despite frequent detection of antimicrobial resistant pathogens; in contrast, 98% of food-related microbial contaminants are classified. Recommendations to fill this microbial identification gap in non-food product recalls are made. Overall, reporting standards for microbial contamination in non-food products must be improved to enable surveillance and for understanding the risks associated with antimicrobial resistant microorganisms.

Enterobacter spp.: Update on Taxonomy, Clinical Aspects, and Emerging Antimicrobial Resistance

The genus Enterobacter is a member of the ESKAPE group, which contains the major resistant bacterial pathogens. First described in 1960, this group member has proven to be more complex as a result of the exponential evolution of phenotypic and genotypic methods. Today, 22 species belong to the Enterobacter genus. These species are described in the environment and have been reported as opportunistic pathogens in plants, animals, and humans. The pathogenicity/virulence of this bacterium remains rather unclear due to the limited amount of work performed to date in this field. In contrast, its resistance against antibacterial agents has been extensively studied. In the face of antibiotic treatment, it is able to manage different mechanisms of resistance via various local and global regulator genes and the modulation of the expression of different proteins, including enzymes (β-lactamases, etc.) or membrane transporters, such as porins and efflux pumps. During various hospital outbreaks, the Enterobacter aerogenes and E. cloacae complex exhibited a multidrug-resistant phenotype, which has stimulated questions about the role of cascade regulation in the emergence of these well-adapted clones.

Microbiological contamination of cosmetic products - observations from Europe, 2005-2018

BACKGROUND

Although cosmetic products are not expected to be fully aseptic, their potential microbiological contamination might be dangerous, especially for immunocompromised patients. The extent of such contamination of cosmetics in Europe is poorly studied.

OBJECTIVES

The objective of this study was to explore whether microbiologically contaminated cosmetic products are available for sale in Europe and what type of contamination was reported.

METHODS

We searched the European Union Rapid Information System for dangerous non-food products (Rapex), a database of non-compliant products among 31 European countries, to identify microbiologically contaminated cosmetics reported between 2005 and 2018, and present a detailed summary of these notifications.

RESULTS

In the years 2005-2018, 104 reports on microbiologically contaminated cosmetics were identified. Twenty of them were products for children. The majority of the products (65.38%) were produced in Rapex member states. In most cases, contamination was caused by Gram-negative bacteria (59.62%), mostly Pseudomonas spp. (35.58%) and Enterobacter spp. (11.54%).

CONCLUSIONS

Gram-negative rod-shaped bacteria are the most common microbiota contaminating cosmetic products in Europe. Most of the reported microbiologically contaminated cosmetics originated from European countries.

Microbiological Safety of Non-Food Products: What Can We Learn from the RAPEX Database?

For consumer protection across borders, the European Union has established the rapid alert system for dangerous non-food products (RAPEX), with the overarching goal of preventing or limiting the sale and use of non-food products that present a serious risk for the health and safety of consumers. In our study, we comprehensively analyzed RAPEX notifications associated with products posing a microbiological risk from 2005 through 2017. Additional information was retrieved from national laboratory reports. A total of 243 microbiologically harmful consumer products triggered notifications in 23 out of 31 participating countries. About half of the products were reported by Spain, Germany, and Italy. Notifications mainly included contaminated toys, cosmetics, and chemical products. Depending on the notifying country, measures taken to prevent the spread of dangerous products were predominantly ordered either by public authorities or economic operators. The interval between microbiological diagnosis and the date of RAPEX notifications considerably varied between RAPEX member states, ranging between a few days and 82 weeks. The nature and extent of RAPEX usage substantially differed among member states, calling for harmonization and optimization. Slight modifications to RAPEX could help to systematically record microbiological hazards, which may improve the assessment of potential health risks due to contaminated non-food products.

Complete Genome Sequence of Pluralibacter gergoviae FB2, an N-Acyl Homoserine Lactone-Degrading Strain Isolated from Packed Fish Paste

Pluralibacter gergoviae FB2, a bacterial strain isolated from packed food, has been found to exhibit quorum-quenching properties. Hence, we report the first, complete genome of P. gergoviae sequenced using the Pacific Biosciences single-molecule, real-time (SMRT) platform.