Efektivitas Sanitizer Komersial Berbasiskan Asam Perasetat terhadap Biofilm Bacillus cereus

Bacillus cereus is known to have the ability to adhere and form biofilms on the surface of stainless steel that causes problems in the food industries. Bacterial biofilms generally can increase resistance to sanitizer treatment. This study aimed to evaluate the ability of peracetic acid-based commercial sanitizer to inactivate B. cereus biofilm on stainless steel (SS) surfaces. Biofilm of B. cereus ATCC 10876 was developed on SS surfaces and treated with 7 commercial peracetic acid-based sanitizers at their recommended dosages. Two sanitizers, i.e. B (peracetic acid and QAC) and F (peracetic acid and acidified water) showing the ability to inactivate B. cereus on solid media at concentration of 200, 400, and 800 ppm were further tested on biofilms with contact times of 1, 3, and 5 minutes. The 48 hours biofilms B. cereus contained 2.78-3.78 CFU/cm2. Both sanitizers B and F had significant effects in inactivating B. cereus biofilm. In general, sanitizer B could reduce more biofilm bacteria at any contact time than sanitizer F. Use of 200 ppm of sanitizer B or F 5 minutes could inactivate 3.04 log CFU/cm2 and 2.68 log CFU/cm2 biofilm, respectively. Exposure of B. cereus biofilm to peracetic acid-based sanitizer resulted in the damage of the extracellular matrix of the biofilms. This study showed that commercial sanitizers containing peracetic acid and quaternary ammonium compounds were effective in inactivating B. cereus biofilms.

Enzymatic Disruption of Biofilms During Cheese Manufacturing: A Mini Review

Bacteria are capable of colonizing industrial processing surfaces creating biofilms on them which may adversely affect the quality and safety of products. Traditional cleaning-in-place (CIP) treatments using caustic and nitric acid solutions have been known to exhibit variable efficiency in eliminating biofilm bacteria. Here, we introduce enzymes as an alternative to traditional CIP treatments and discuss their mechanism of action against bacterial biofilms in cheese manufacturing. In addition, we discuss research gaps namely thermal stability, substrate specificity and residual activity of enzymes that may play a vital role in the selection of enzymes with optimal effectiveness against multi species biofilms. The outcome of this mini review will aid in the development of a novel and sustainable enzyme-based CIP treatment during cheese manufacturing in the future.

The efficacy of chlorine-based disinfectants against planktonic and biofilm bacteria for decentralised point-of-use drinking water

Chlorine solutions are used extensively for the production of biologically safe drinking water. The capability of point-of-use [POU] drinking water treatment systems has gained interest in locations where centralised treatment systems and distribution networks are not practical. This study investigated the antimicrobial and anti-biofilm activity of three chlorine-based disinfectants (hypochlorite ions [OCl-], hypochlorous acid [HOCl] and electrochemically activated solutions [ECAS]) for use in POU drinking water applications. The relative antimicrobial activity was compared within bactericidal suspension assays (BS EN 1040 and BS EN 1276) using Escherichia coli. The anti-biofilm activity was compared utilising established sessile Pseudomonas aeruginosa within a Centre for Disease Control [CDC] biofilm reactor. HOCl exhibited the greatest antimicrobial activity against planktonic E. coli at >50 mg L−1 free chlorine, in the presence of organic loading (bovine serum albumen). However, ECAS exhibited significantly greater anti-biofilm activity compared to OCl- and HOCl against P. aeruginosa biofilms at ≥50 mg L−1 free chlorine. Based on this evidence disinfectants where HOCl is the dominant chlorine species (HOCl and ECAS) would be appropriate alternative chlorine-based disinfectants for POU drinking water applications.

Improving the Efficacy of Antimicrobials against Biofilm-Embedded Bacteria Using Bovine Hyaluronidase Azoximer (Longidaza®)

While in a biofilm, bacteria are extremely resistant to both antimicrobials and the immune system, leading to the development of chronic infection. Here, we show that bovine hyaluronidase fused with a copolymer of 1,4-ethylenepiperazine N-oxide and (N-carboxymethyl) -1,4-ethylenepiperazinium bromide (Longidaza®) destroys both mono- and dual-species biofilms formed by various bacteria. After 4 h of treatment with 750 units of the enzyme, the residual biofilms of Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Pseudomonas aeruginosa and Klebsiella pneumoniae preserved about 50–70% of their initial mass. Biomasses of dual-species biofilms formed by S. aureus and the four latter species were reduced 1.5-fold after 24 h treatment, while the significant destruction of S. aureus–P. aeruginosa and S. aureus–K. pneumoniae was also observed after 4 h of treatment with Longidaza®. Furthermore, when applied in combination, Longidaza® increased the efficacy of various antimicrobials against biofilm-embedded bacteria, although with various increase-factor values depending on both the bacterial species and antimicrobials chosen. Taken together, our data indicate that Longidaza® destroys the biofilm structure, facilitating the penetration of antimicrobials through the biofilm, and in this way improving their efficacy, lowering the required dose and thus also potentially reducing the associated side effects.

Antibiotic susceptibility of Staphylococcus aureus with different degrees of biofilm formation

Staphylococcus aureus is one of the most common pathogens in biofilm-associated chronic infections. S. aureus living within biofilms evades the host immune response and is more resistant to antibiotics than planktonic bacteria. In this study, we generated S. aureus with low and high levels of biofilm formation using the rbf (regulator of biofilm formation) gene and performed a BioTimer assay to determine the minimum inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) of various types of antibiotics. We showed that biofilm formation by S. aureus had a greater effect on MBC than MIC, probably due to the different growth modes between planktonic and biofilm bacteria. Importantly, we found that the MBC for biofilm S. aureus was much higher than that for planktonic cells, but there was little difference in MBC between low and high levels of biofilm formation. These results suggest that once the biofilm is formed, the bactericidal activity of antibiotics is significantly reduced, regardless of the degree of S. aureus biofilm formation. We propose that S. aureus strains with varying degrees of biofilm formation may be useful for evaluating the anti-biofilm activity of antimicrobial agents and understanding antibiotic resistance mechanisms by biofilm development.

Antibiogram of Biofilm Producing Bacteria Isolated from Urine of Patients in Three Hospitals in Port Harcourt, Rivers State

Aim: The aim of this study was to determine the antibiogram of biofilm producing bacteria isolated from urine of patients in three hospitals in Port Harcourt, Rivers State. Study Design: The study employs statistical analysis of the data and interpretation Place and Duration of Study: The study was conducted at three (3) hospitals; University of Port Harcourt Teaching Hospital (UPTH), Meridian Hospital D / line branch (MRD1) and Meridian Hospital Ikoku branch, all located in Port Harcourt, Rivers State. Sample collection was for three (3) months, analysis was carried out daily and it lasted for six (6) months. Methodology: A total of Forty-five (45) urine samples were collected for a period of three (3) months from the three (3) hospitals. The samples were labelled properly, according to date and time of collection. The collected samples were subjected to standard microbiological procedures which includes standard plate counts, identification, biofilm screening, sensitivity testing using Kirby-Bauer disk diffusion method, Phenotypic screening of extended spectrum beta lactamase and molecular characterization of the isolates Results: The results of the bacterial population of urine samples from the hospitals showed that the total heterotrophic bacterial counts for Meridian Hospital D/line (MRD1), Meridian Hospital Ikoku (MRD2) and University of Port Harcourt Teaching Hospital (UPTH) ranged from 4.93 - 6.30 x107cfu/ml. The Total coliform count ranged from 1.89-3.04 x106cfu/ml for Meridian Hospital D/line (MRD1), Meridian Hospital Ikoku (MRD2) and University of Port Harcourt Teaching Hospital (UPTH). Total faecal coliform counts ranged from 0.78-1.11 x105CFU/ml for Meridian Hospital D/line (MRD1), Meridian Hospital Ikoku (MRD2) and University of Port Harcourt Teaching Hospital (UPTH). A total of fifty-eight (58) bacterial isolates were isolated from urine of patients and 36(62.1%) isolates were identified as biofilm producers. The biofilm bacteria identified were 17.2% Staphylococcus,6.9% E. coli, 10.3% Pseudomonas, 6.9% Proteus ,10.3% Bacillus and 10.3% Enterococcus species. Biofilm forming ability of bacteria is considered a virulent factor and it is implicated to being a possible cause of increased resistance to most antibiotics. Varying susceptibility pattern was observed among biofilm isolates. Biofilm bacteria were resistant to several groups of antibiotics. Ofloxacin, Gentamycin, Imipenem and Nitrofurantoin can be used as drug of interest for most bacterial biofilm urinary tract infections. CTX-M and TET A gene were identified in the biofilm bacteria in this study to be possible factors that confer resistance to antibiotics. The presence of icaD and papC gene in the isolates whose genome were studied have been found to be possible factors that confers biofilm producing ability. This study indicates the emergence and rapid spread of biofilm producing bacteria and their resistance to antibiotics. Therefore, strict infection control practices as well as therapeutic guidance for confirmed infections should be rapidly initiated.

The Use of Zwitterionic Methylmethacrylat Coated Silicone Inhibits Bacterial Adhesion and Biofilm Formation of Staphylococcus aureus

In recent decades, biofilm-associated infections have become a major problem in many medical fields, leading to a high burden on patients and enormous costs for the healthcare system. Microbial infestations are caused by opportunistic pathogens which often enter the incision already during implantation. In the subsequently formed biofilm bacteria are protected from the hosts immune system and antibiotic action. Therefore, the development of modified, anti-microbial implant materials displays an indispensable task. Thermoplastic polyurethane (TPU) represents the state-of-the-art material in implant manufacturing. Due to the constantly growing areas of application and the associated necessary adjustments, the optimization of these materials is essential. In the present study, modified liquid silicone rubber (LSR) surfaces were compared with two of the most commonly used TPUs in terms of bacterial colonization and biofilm formation. The tests were conducted with the clinically relevant bacterial strains Staphylococcus aureus and Staphylococcus epidermidis. Crystal violet staining and scanning electron microscopy showed reduced adhesion of bacteria and thus biofilm formation on these new materials, suggesting that the investigated materials are promising candidates for implant manufacturing.

IMMUNITY AND BACTERIAL BIOFILMS: CURRENT STATUS OF THE MATTER (LITERATURE REVIEW)

The problem of prevention and treatment of infectious diseases in practical health care is one of the most difficult, unsolved and priority ones. At the same time, the fact of biofilm formation by microorganisms-causative agents of infectious diseases has already been proved, which leads to an increase in the resistance of pathogens of infectious-inflammatory diseases to antibacterial drugs, chronization of the infectious process, and an atypical course of the disease. The results of numerous studies have shown the relationship between the immune system and bacterial biofilms. The effect of the links of humoral and cellular immunity on the matrix of biofilms or some of its components has been described. Neutrophils, that play a key role in phagocytosis rank first in antibiofilm immunity. However, it has been shown that the polysaccharide matrix of biofilms reduces phagocytosis by inhibiting the phagocytic clearance of biofilm bacteria. Bacteria of biofilms have become able to use many protective reactions of the immune system, designed to fight with microorganisms for their own purposes for development, growth, nutrition. For example, lysozyme enhanced the adhesion of S. aureus to the surface, triggering biofilm formation. Several studies have shown the destruction of biofilms when exposed to blood serum. Other studies have demonstrated the activation of the complement system in the presence of biofilm.