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Brazilian Journal of Microbiology :... Jul 2024Biosurfactants, sustainable alternatives to petrochemical surfactants, are gaining attention for their potential in medical applications. This study focuses on...
Biosurfactants, sustainable alternatives to petrochemical surfactants, are gaining attention for their potential in medical applications. This study focuses on producing, purifying, and characterizing a glycolipid biosurfactant from Candida sp. UFSJ7A, particularly for its application in biofilm prevention on siliconized latex catheter surfaces. The glycolipid was extracted and characterized, revealing a critical micellar concentration (CMC) of 0.98 mg/mL, indicating its efficiency at low concentrations. Its composition, confirmed through Fourier transform infrared spectroscopy (FT-IR) and thin layer chromatography (TLC), identified it as an anionic biosurfactant with a significant ionic charge of -14.8 mV. This anionic nature contributes to its biofilm prevention capabilities. The glycolipid showed a high emulsification index (E) for toluene, gasoline, and soy oil and maintained stability under various pH and temperature conditions. Notably, its anti-adhesion activity against biofilms formed by Escherichia coli, Enterococcus faecalis, and Candida albicans was substantial. When siliconized latex catheter surfaces were preconditioned with 2 mg/mL of the glycolipid, biofilm formation was reduced by up to 97% for E. coli and C. albicans and 57% for E. faecalis. These results are particularly significant when compared to the efficacy of conventional surfactants like SDS, especially for E. coli and C. albicans. This study highlights glycolipids' potential as a biotechnological tool in reducing biofilm-associated infections on medical devices, demonstrating their promising applicability in healthcare settings.
PubMed: 38954220
DOI: 10.1007/s42770-024-01431-w -
PeerJ 2024This study explored the utilization of luffa sponge (LS) in enhancing acetification processes. LS is known for having high porosity and specific surface area, and can...
BACKGROUND
This study explored the utilization of luffa sponge (LS) in enhancing acetification processes. LS is known for having high porosity and specific surface area, and can provide a novel means of supporting the growth of acetic acid bacteria (AAB) to improve biomass yield and acetification rate, and thereby promote more efficient and sustainable vinegar production. Moreover, the promising potential of LS and luffa sponge coated with κ-carrageenan (LSK) means they may represent effective alternatives for the co-production of industrially valuable bioproducts, for example bacterial cellulose (BC) and acetic acid.
METHODS
LS and LSK were employed as adsorbents for UMCC 2951 in a submerged semi-continuous acetification process. Experiments were conducted under reciprocal shaking at 1 Hz and a temperature of 32 °C. The performance of the two systems (LS-AAB and LSK-AAB respectively) was evaluated based on cell dry weight (CDW), acetification rate, and BC biofilm formation.
RESULTS
The use of LS significantly increased the biomass yield during acetification, achieving a CDW of 3.34 mg/L versus the 0.91 mg/L obtained with planktonic cells. Coating LS with κ-carrageenan further enhanced yield, with a CDW of 4.45 mg/L. Acetification rates were also higher in the LSK-AAB system, reaching 3.33 ± 0.05 g/L d as opposed to 2.45 ± 0.05 g/L d for LS-AAB and 1.13 ± 0.05 g/L d for planktonic cells. Additionally, BC biofilm formation during the second operational cycle was more pronounced in the LSK-AAB system (37.0 ± 3.0 mg/L, as opposed to 25.0 ± 2.0 mg/L in LS-AAB).
CONCLUSIONS
This study demonstrates that LS significantly improves the efficiency of the acetification process, particularly when enhanced with κ-carrageenan. The increased biomass yield, accelerated acetification, and enhanced BC biofilm formation highlight the potential of the LS-AAB system, and especially the LSK-AAB variant, in sustainable and effective vinegar production. These systems offer a promising approach for small-scale, semi-continuous acetification processes that aligns with eco-friendly practices and caters to specialized market needs. Finally, this innovative method facilitates the dual production of acetic acid and bacterial cellulose, with potential applications in biotechnological fields.
Topics: Carrageenan; Acetobacter; Biomass; Acetic Acid; Luffa; Adsorption; Cellulose; Biofilms
PubMed: 38952965
DOI: 10.7717/peerj.17650 -
Nanotechnology, Science and Applications 2024Antibacterial and antibiofilm properties of magnesium oxide nanoparticles (MgONPs) mixture assessed against (), in addition to examining MgONPs varnish impact on the...
PURPOSE
Antibacterial and antibiofilm properties of magnesium oxide nanoparticles (MgONPs) mixture assessed against (), in addition to examining MgONPs varnish impact on the preservation of the tooth color and inhibition of methylene blue diffusion to the enamel.
METHODS
MgONPs mixture was prepared in deionized water (DW), absolute ethanol (E), and rosin with ethanol (RE), named varnish. The antibacterial and antibiofilm capacities of MgONPs mixtures were tested by agar well diffusion, colony-forming unit (CFU), and biofilm inhibition microtiter methods in triplicate and compared to sodium fluoride varnish (NaF) and chlorhexidine mouthwash (ChX). A spectrophotometer was used to record basic tooth color. The artificial demineralization was initiated for 96 h. Then, experimental materials were applied to the corresponding group, and 10-day pH cycles proceeded. Then, the color was recorded in the same ambient environment. The methylene blue diffusion was evaluated by staining the samples for 24 h. After that, the diffusion test was calculated by a digital camera attached to the stereomicroscope.
RESULTS
The agar well diffusion test expressed a significant inhibition zone with all MgONPs mixtures (p = 0.000), and maximum inhibition zone diameter associated with MgONPs-RE. The same finding was observed in the CFU test. Additionally, 2.5%, 5%, and 10% MgONPs-RE varnish showed strong biofilm inhibition capacity (p = 0.039) compared to NaF and ChX groups that inhibit biofilm formation moderately (p = 0.003). The study shows that the 5% MgONPs-RE varnish maintains basic tooth color with minimal methylene blue diffusion compared to NaF varnish (p = 0.00).
CONCLUSION
Evaluating MgONPs as a mixture revealed antibacterial and antibiofilm capacity against with a higher effect of MgONPs-RE varnish. Also, examining the topical effect of MgONPs-RE varnish on the preservation of the tooth color after pH cycle challenges and methylene blue diffusion to enamel confirmed the high performance of MgONPs-RE varnish at 5%.
PubMed: 38952853
DOI: 10.2147/NSA.S462771 -
Cureus Jun 2024Background Periodontal disease poses a significant oral health challenge, involving inflammatory conditions impacting tooth-supporting structures. Treponema denticola, a...
Background Periodontal disease poses a significant oral health challenge, involving inflammatory conditions impacting tooth-supporting structures. Treponema denticola, a "red complex" organism, plays a crucial role in periodontal pathogenesis, forming biofilms in subgingival environments and contributing to dysbiosis. Antimicrobial therapy is pivotal in managing periodontal disease, requiring a nuanced understanding of susceptibility patterns exhibited by key pathogens like T. denticola Aims and objectives This study aims to investigate the antimicrobial susceptibility and resistance profiles of Treponema denticola, a prominent bacterium in periodontal disease, by examining its responses to various antimicrobial agents commonly used in periodontal therapy. Methodology Plaque samples were meticulously collected from individuals diagnosed with periodontal disease to ensure a diverse representation of the oral microbiome. All the samples were cultured, and red complex bacteria were isolated under anaerobic culture. Treponema denticola isolates were cultured from these samples under anaerobic conditions, and molecular techniques were employed for species identification. A comprehensive panel of antimicrobial agents was selected to assess the response of Treponema denticola. In vitro antimicrobial susceptibility testing (AST) was conducted using the antimicrobial gradient method, employing a hybrid approach combining elements of disk-diffusion and dilution methods. Results Treponema denticola had exhibited resistance to metronidazole, a commonly used antibiotic effective against anaerobic bacteria, emphasizing limitations in its applicability. However, the bacterium displayed sensitivity to tetracycline, imipenem, cefoperazone, chloramphenicol, clindamycin, and moxifloxacin, offering diverse therapeutic options. The antimicrobial gradient strip test provided detailed minimum inhibitory concentration (MIC) values, contributing to a nuanced understanding of susceptibility and resistance patterns. Conclusion This study significantly advances our understanding of Treponema denticola's antimicrobial susceptibility and resistance profiles in the context of periodontal disease. The findings underscore the importance of tailored treatment strategies and contribute to broader efforts in antimicrobial stewardship, aligning with global initiatives to combat antibiotic resistance. This research lays the foundation for more effective and personalized approaches to periodontal care, emphasizing the intricate microbial dynamics associated with periodontal health and disease.
PubMed: 38952590
DOI: 10.7759/cureus.61497 -
Frontiers in Pediatrics 2024Preterm birth is a growing problem worldwide. Staying at a neonatal intensive care unit (NICU) after birth is critical for the survival of preterm infants whose feeding...
INTRODUCTION
Preterm birth is a growing problem worldwide. Staying at a neonatal intensive care unit (NICU) after birth is critical for the survival of preterm infants whose feeding often requires the use of nasogastric enteral feeding tubes (NEFT). These can be colonized by hospital-associated pathobionts that can access the gut of the preterm infants through this route. Since the gut microbiota is the most impactful factor on maturation of the immune system, any disturbance in this may condition their health. Therefore, the aim of this study is to assess the impact of NEFT-associated microbial communities on the establishment of the gut microbiota in preterm infants.
MATERIAL AND METHODS
A metataxonomic analysis of fecal and NEFT-related samples obtained during the first 2 weeks of life of preterm infants was performed. The potential sharing of strains isolated from the same set of samples of bacterial species involved in NICU's outbreaks, was assessed by Random Amplification of Polymorphic DNA (RAPD) genotyping.
RESULTS
In the samples taken 48 h after birth (NEFT-1 and Me/F1), spp. was the most abundant genera (62% and 14%, respectively) and it was latter displaced to 5.5% and 0.45%, respectively by . Significant differences in beta diversity were detected in NEFT and fecal samples taken at day 17 after birth (NEFT-3 and F3) ( = 0.003 and = 0.024, respectively). Significant positive correlations were found between the most relevant genera detected in NEFT-3 and F3. 28% of the patients shared at least one RAPD-PCR profile in fecal and NEFT samples and 11% of the total profiles were found at least once simultaneously in NEFT and fecal samples from the same patient.
CONCLUSION
The results indicate a parallel bacterial colonization of the gut of preterm neonates and the NEFTs used for feeding, potentially involving strain sharing between these niches. Moreover, the same bacterial RAPD profiles were found in neonates hospitalized in different boxes, suggesting a microbial transference within the NICU environment. This study may assist clinical staff in implementing best practices to mitigate the spread of pathogens that could threaten the health of preterm infants.
PubMed: 38952433
DOI: 10.3389/fped.2024.1397398 -
Journal of Nanobiotechnology Jul 2024Diabetic wounds present significant challenges, specifically in terms of bacterial infection and delayed healing. Therefore, it is crucial to address local bacterial...
BACKGROUND
Diabetic wounds present significant challenges, specifically in terms of bacterial infection and delayed healing. Therefore, it is crucial to address local bacterial issues and promote accelerated wound healing. In this investigation, we utilized electrospinning to fabricate microgel/nanofiber membranes encapsulating MXene-encapsulated microgels and chitosan/gelatin polymers.
RESULTS
The film dressing facilitates programmed photothermal therapy (PPT) and mild photothermal therapy (MPTT) under near-infrared (NIR), showcasing swift and extensive antibacterial and biofilm-disrupting capabilities. The PPT effect achieves prompt sterilization within 5 min at 52 °C and disperses mature biofilm within 10 min. Concurrently, by adjusting the NIR power to induce local mild heating (42 °C), the dressing stimulates fibroblast proliferation and migration, significantly enhancing vascularization. Moreover, in vivo experimentation successfully validates the film dressing, underscoring its immense potential in addressing the intricacies of diabetic wounds.
CONCLUSIONS
The MXene microgel-loaded nanofiber dressing employs temperature-coordinated photothermal therapy, effectively amalgamating the advantageous features of high-temperature sterilization and low-temperature promotion of wound healing. It exhibits rapid, broad-spectrum antibacterial and biofilm-disrupting capabilities, exceptional biocompatibility, and noteworthy effects on promoting cell proliferation and vascularization. These results affirm the efficacy of our nanofiber dressing, highlighting its significant potential in addressing the challenge of diabetic wounds struggling to heal due to infection.
Topics: Wound Healing; Nanofibers; Photothermal Therapy; Animals; Bandages; Anti-Bacterial Agents; Mice; Biofilms; Chitosan; Male; Diabetes Mellitus, Experimental; Temperature; Rats; Infrared Rays; Cell Proliferation; Rats, Sprague-Dawley; Humans; Wound Infection
PubMed: 38951903
DOI: 10.1186/s12951-024-02621-2 -
Nature Microbiology Jul 2024
PubMed: 38951665
DOI: 10.1038/s41564-024-01743-5 -
Brazilian Journal of Microbiology :... Jul 2024Chitinases are promising enzymes for a multitude of applications, including chitooligosaccharide (COS) synthesis for food and pharmaceutical uses and marine waste...
Chitinases are promising enzymes for a multitude of applications, including chitooligosaccharide (COS) synthesis for food and pharmaceutical uses and marine waste management. Owing to fungal diversity, fungal chitinases may offer alternatives for chitin degradation and industrial applications. The rapid reproduction cycle, inexpensive growth media, and ease of handling of fungi may also contribute to reducing enzyme production costs. Thus, this study aimed to identify fungal species with chitinolytic potential and optimize chitinase production by submerged culture and enzyme characterization using shrimp chitin. Three fungal species, Coriolopsis byrsina, Trichoderma reesei, and Trichoderma harzianum, were selected for chitinase production. The highest endochitinase production was achieved in C. byrsina after 168 h cultivation (0.3 U mL). The optimal temperature for enzyme activity was similar for the three fungal species (up to 45 and 55 ºC for endochitinases and exochitinases, respectively). The effect of pH on activity indicated maximum hydrolysis in acidic pH (4-7). In addition, the crude T. reesei extract showed promising properties for removing Candida albicans biofilms. This study showed the possibility of using shrimp chitin to induce chitinase production and enzymes that can be applied in different industrial sectors.
PubMed: 38951478
DOI: 10.1007/s42770-024-01432-9 -
ACS Applied Materials & Interfaces Jul 2024Better infection control will accelerate wound healing and alleviate associated healthcare burdens. Traditional antibacterial dressings often inadequately control...
Better infection control will accelerate wound healing and alleviate associated healthcare burdens. Traditional antibacterial dressings often inadequately control infections, inadvertently promoting antibacterial resistance. Our research unveils a novel, dual-functional living dressing that autonomously generates antibacterial agents and delivers electrical stimulation, harnessing the power of spore-forming . This dressing is built on an innovative wearable microbial fuel cell (MFC) framework, using endospores as a powerful, dormant biocatalyst. The endospores are resilient, reactivating in nutrient-rich wound exudate to produce electricity and antibacterial compounds. The combination allows to outcompete pathogens for food and other resources, thus fighting infections. The strategy is enhanced by the extracellular synthesis of tin oxide and copper oxide nanoparticles on the endospore surface, boosting antibacterial action, and electrical stimulation. Moreover, the MFC framework introduces a pioneering dressing design featuring a conductive hydrogel embedded within a paper-based substrate. The arrangement ensures cell stability and sustains a healing-friendly moist environment. Our approach has proven very effective against three key pathogens in biofilms: , , and demonstrating exceptional capabilities in both in vitro and ex vivo models. Our innovation marks a significant leap forward in wearable MFC-based wound care, offering a potent solution for treating infected wounds.
PubMed: 38950522
DOI: 10.1021/acsami.4c06303 -
ACS Applied Bio Materials Jul 2024Fungal proliferation can lead to adverse effects for human health, due to the production of pathogenic and allergenic toxins and also through the creation of fungal...
Fungal proliferation can lead to adverse effects for human health, due to the production of pathogenic and allergenic toxins and also through the creation of fungal biofilms on sensitive surfaces (i.e., medical equipment). On top of that, food spoilage from fungal activity is a major issue, with food losses exceeding 30% annually. In this study, the effect of the surface micro- and nanotopography, material (aluminum, Al, and poly(methyl methacrylate), PMMA), and wettability against is investigated. The fungal activity is monitored using dynamic conditions by immersing the surfaces inside fungal spore-containing suspensions and measuring the fungal biomass growth, while the surfaces with the optimum antifungal properties are also evaluated by placing them near spore suspensions of on agar plates. Al- and PMMA-based superhydrophobic surfaces demonstrate a passive-like antifungal profile, and the fungal growth is significantly reduced (1.6-2.2 times lower biomass). On the other hand, superhydrophilic PMMA surfaces enhance fungal proliferation, resulting in a 2.6 times higher fungal total dry weight. In addition, superhydrophobic surfaces of both materials exhibit antifouling and antiadhesive properties, whereas both superhydrophobic surfaces also create an "inhibition" zone against the growth of when tested on agar plates.
PubMed: 38950150
DOI: 10.1021/acsabm.4c00387