Antibacterial and Anti-Biofilm Activity of Omega-3 Polyunsaturated Fatty Acids against Periprosthetic Joint Infections-Isolated Multi-Drug Resistant Strains

Eicosapentaenoic acid as an antibiofilm agent disrupts mature biofilms of Candida albicans

The biofilm formation of Candida albicans, a major human fungal pathogen, represents a crucial virulence factor during candidiasis. Eicosapentaenoic acid (EPA), a polyunsaturated fatty acid, has emerged as a potential antibiofilm agent against C. albicans. Herein, we aim to investigate the antifungal effect of EPA (1 mM) on the mature biofilm of C. albicans and explore the underlying mechanism. Crystal violet and XTT assays showed that EPA exerted a strong inhibitory efficacy on preformed biofilms in C. albicans. Biofilm architecture and cell viability were observed using scanning electron microscopy and confocal laser scanning microscopy, indicating that EPA could block the yeast-to-hypha transition and damage the structure, thereby exhibiting antibiofilm activity. RNA sequencing analysis revealed that EPA treatment led to the downregulation of genes associated with hyphal formation and biofilm development. From the signaling pathway perspective, EPA regulated the C. albicans biofilms involving two signaling pathways, namely, Ras1-cAMP-PKA and Cek-MAPK pathways. Additionally, the EPA could effectively reduce the production of key messenger cAMP in the Ras1-cAMP-PKA pathway. Interestingly, in response to EPA, ergosterol biosynthesis-related genes were down-regulated, indicating EPA as antifungal agent might reduce the risk of developing drug resistance. The findings of this study highlight the potential of EPA as an alternative or adjunctive antibiofilm agent against C. albicans-related infections.

Investigating the association between polyunsaturated fatty acids and osteomyelitis by Mendelian randomization

Osteomyelitis, characterized by bone inflammation and infection, poses a significant global health burden. This Mendelian randomization (MR) study investigates the causal relationship between polyunsaturated fatty acids (PUFAs) and osteomyelitis risk. By using GWAS data from 114,999 individuals, we explore specific PUFAs and their genetic variations using Inverse variance weighted (IVW), MR-Egger and weighted median methods. The results reveal a suggestive association between genetically predicted higher docosahexaenoic acid (DHA) and omega-6 levels with increased osteomyelitis risk. Conversely, a negative association is found for the omega-6:3 ratio. Linoleic acid, omega-3, and omega-6 show no significant associations. Heterogeneity and pleiotropy analyses support result robustness, indicating minimal confounding effects. Sensitivity analyses confirm the stability of findings. Our MR analysis challenges the presumed protective role of omega-3 in osteomyelitis, suggesting a nuanced relationship where DHA may pose an increased risk. The study underscores the complexity of fatty acid interactions influenced by genetic variability and dietary nuances. Further research is essential to unravel underlying mechanisms and translate these findings into actionable strategies for osteomyelitis prevention and treatment.

Immunology of the Bovine Mammary Gland: Advances in Recent Years

Bovine mastitis remains the most costly disease in the dairy industry due to its impact on milk production, milk quality, and animal welfare. Optimal immunity is essential for the mammary gland to resist infections, efficiently clear them, and limit damage to mammary tissue. This article highlights recent advancements built on previous knowledge exploring opportunities for enhancing mammary gland immune responses. Ultimately, these improvements aim to increase the resistance of the mammary gland to infections and reduce the costs associated with this disease in the dairy industry.

Effects of Vitamin D, Melatonin, and Omega-3 Fatty Acids on Periodontal Health: A Narrative Review

Periodontitis is a chronic inflammatory disease characterized by the destruction of tooth-supporting structures, influenced by immune system dysregulation, oxidative stress, and imbalances in bone metabolism. Given its multifactorial pathogenesis, bioactive compounds such as vitamin D, melatonin, and omega-3 fatty acids have emerged as potential adjuncts to periodontal therapy due to their immunomodulatory, anti-inflammatory, and antioxidative properties. This narrative review explores the role of these three supplements in periodontal health, their potential in synergistic effects, and existing research gaps, providing a foundation for future studies on their clinical applications. Vitamin D is essential for calcium homeostasis, bone remodeling, and immune function. It modulates both innate and adaptive immune responses, enhancing antimicrobial peptide production and reducing inflammatory cytokine expression. Omega-3 fatty acids reduce the production of pro-inflammatory eicosanoids while promoting the synthesis of pro-resolving lipid mediators, contributing to bone preservation and immune balance. Melatonin, known for its antioxidant and osteogenic properties, supports bone remodeling by stimulating osteoblast proliferation and inhibiting osteoclast activity, while also regulating circadian rhythms, which may influence oral health. Although these bioactive compounds show promising effects in preclinical and clinical studies, significant knowledge gaps remain regarding optimal dosages, long-term efficacy, combined use, and standardized treatment protocols. Further clinical trials are necessary to elucidate their therapeutic value in periodontal disease management, especially those focused on their potential synergistic mechanisms. Understanding their synergistic mechanisms may open new avenues for adjunctive strategies in periodontal therapy.

Eicosapentaenoic Acid and Docosahexaenoic Acid as an Antimicrobial Agent in Orthopedics-An In Vitro Study About the Race for Surface

BACKGROUND

The burden of prosthetic joint infection in combination with antibiotic-resistant bacterial strains is a rising dilemma for patients experiencing total joint replacements. Around 0.8-2% of patients experience prosthetic joint infections, while up to 21% of patients are considered fatal cases after 5 years. Staphylococcus aureus is one of the main reasons for prosthetic joint infections. Its capability of forming biofilms and developing mechanisms against antibiotics is one of the most dangerous clinical topics being currently discussed. Previous studies have shown the promising results of omega-3 fatty acids as an antimicrobial agent against Staphylococcus aureus. Though an antimicrobial effect has been examined, the influence of polyunsaturated fatty acids on Staphylococcus aureus in the presence of human osteoblasts has not been reported yet. In this study, we aimed to investigate the influence of omega-3 fatty acids on the biofilm formation of Staphylococcus aureus ATCC 29213 in the presence of hFOB 1.19 cells. The co-culture setup helped to examine the influence of omega-3 fatty acids on the race for surface to simulate prosthetic joint infections.

METHODS

In this study, we tested Staphylococcus aureus ATCC 29213 co-cultured with human fetal osteoblasts hFOB 1.19 in the presence of sub-MIC and MIC concentrations of docosahexaenoic acid (1.25 mg/L, 2.5 mg/L) and eicosapentaenoic acid (0.15 mg/L, 0.3 mg/L) after 1, 6 and 24 h of incubation. After establishing the co-culture, cell culture and biofilm, we performed colony-forming unit counting and cell counting to examine cell survivability. In addition, we carried out scanning electron microscopy to study the race for surface behaviour of the cells.

RESULTS

We found a protective influence of omega-3 fatty acids on osteoblasts when present in co-culture with Staphylococcus aureus after 6 h of incubation. Omega-3 fatty acids increase the cell survival of osteoblasts after 6 h in a co-culture with bacteria and are able to influence the race for surface. In this study, the strain of Staphylcoccus aureus ATCC 29213 showed signs of growth inhibition within the first 6 h.

CONCLUSIONS

Omega-3 fatty acids can be a valuable antimicrobial agent in terms of decreasing the risk of on-site infection during surgery. Omega-3 fatty acids were shown to decrease the bacterial load within the first 6 h of incubation and increase the survivability of osteoblasts.

Fish oil-containing edible films with active film incorporated with extract of Psidium guajava leaves: preparation and characterization of double-layered edible film

The utilization of zein and gum arabic has grown in an attempt to formulate wall materials based on protein-polysaccharide complexes. This mixture provides a versatile delivery system for hydrophilic (guava leaf extract, GLE) or lipophilic (fish oil, FO) bioactive compounds, and it can be used as an edible film-forming polymer. This study was undertaken to characterize FO-containing edible films that were double-layered with a film containing GLE. Modified zein and gum arabic solutions (MG complex) were mixed at a ratio of 1:1.5 (v/v), adjusted to pH 5, added with glycerol (20% of the complex) and FO (5% of the complex), and finally adjusted to pH 5. This was prepared as the bottom/lower layer. The upper/active layer was prepared by mixing MG complex, glycerol, and GLE (1, 3, and 5% w/v of the complex). The total phenolic and flavonoid contents in GLE were 15.81 mg GAE/g extract and 6.99 mg QE/g extract, respectively. The IC50 of the DPPH radical scavenging activity of GLE was 26.86 ppm with antibacterial activity against Bacillus subtilis and Escherichia coli of 9.83 and 12.55 mm. The total plate counts of double-layered films containing GLE were retained below 3 log CFU/g during 28-day storage. The peroxide values of these films were dimmed for no more than 9.08 meq/kg sample on day 28 of storage. Thickness (872.00-971.67 μm), water vapor transmission rate (12.99-17.04 g/m 2/day), tensile strength (1.56-2.02 kPa), elongation at break (61.53-75.41%), glass transition (52.74-57.50°C), melting peak (131.59-142.35°C), inhibition against B. subtilis (33.67-40.58 mm), and inhibition against E. coli (2.05-9.04 mm) were obtained by double-layered films. GLE can be successfully incorporated into the active layer of a double-layer film to improve its characteristics while significantly slowing down the microbial contamination and oxidation rate. MG complex and FO can also contribute to the performance of the edible film.

Antimicrobial effects of a multimodal wound matrix against methicillin-resistant Staphylococcus aureus and Pseudomonas aeruginosa in an in vitro and an in vivo porcine wound model

Chronic non-healing wounds pose significant challenges due to an elevated inflammatory response caused in part by bacterial contamination (Physiol Rev. 2019;99:665). These wounds lead to billions being spent in the health care system worldwide (N Engl J Med. 2017;376:2367, Int J Pharm. 2014;463:119). We studied the in-vitro and in-vivo antimicrobial effects of a multimodal wound matrix (MWM) against two common wound pathogens, Methicillin-Resistant Staphylococcus aureus (MRSA USA300) and Pseudomonas aeruginosa ATCC 27312 (PA27312) (Int Wound J. 2019;16:634). The in-vitro study conducted was a zone of inhibition test with the two microbes at 104 Log CFU/mL inoculated on Tryptic soy agar with 5% sheep blood (TSAII) plates. Treatments used were MWM, Mupirocin (Positive control for MRSA), Silver Sulfadiazine (Positive Control for PA), Petrolatum and Sterile Saline (both serving as Negative Controls). Treatments were allowed to diffuse into the agar for 3 h and then were incubated for 24 h at 37°C. The in-vivo study utilized a deep dermal porcine wound model (22 × 22 × 3 mm) created on six animals. Three animals were inoculated with MRSA USA300 and the other three with PA27312 with each allowing a 72-h biofilm formation. After 72 h, baseline wounds were assessed for bacterial concentration and all remaining wounds were treated with either MWM alone, Silver Treatment or Untreated Control. Wounds were assessed on days 4, 8 and 12 after treatment application for microbiological analysis. In-vitro, MWM exhibited significant inhibition of MRSA USA300 and PA27312 growth when compared to negative controls (p ≤ 0.05). Likewise, in-vivo, the MWM-treated wounds exhibited a significant (p ≤ 0.05) bacterial reduction compared to all other treatment groups, especially on days 8 and 12 for both pathogens. MWM demonstrated promise in addressing colonized wounds with biofilms. Additional studies on MWM's benefits and comparisons with existing treatments are warranted to optimize wound care strategies (Adv Wound Care. 2021;10:281).

Omega Fatty Acid-Based Therapy for Healing of Recalcitrant Wounds in Patients with Complex Comorbidities

ABSTRACT

The human body possesses the unique ability to repair itself after injury through complex, sequential phases. Current development of advanced wound care therapies generally focuses on addressing a single aspect of this biological process that can result in delayed or ineffective wound healing. When patients present with further systemic and local confounding pathologies, it can result in painful, chronic wounds that are especially challenging to treat.In this case report, the authors demonstrate how treatment with a novel multimodal wound matrix expedited healing and decreased pain in two patients who had each been unresponsive to treatment with advanced modalities for more than 7 months. The first patient had factor V Leiden, and the second patient had sickle cell disease. Use of a once-weekly treatment protocol with the multimodal wound matrix, combined with sharp debridement when deemed clinically necessary, resulted in elimination of pain and expedited wound healing to closure. The wound matrix's omega fatty acid-based formulation is designed to target multiple factors common among hard-to-heal wounds that when not addressed can adversely inhibit the wound-healing cascade.

Antibacterial and anti-biofilm activities of antibiotic-free phosphatidylglycerol/docosahexaenoic acid lamellar and non-lamellar liquid crystalline nanoparticles

Infectious diseases, particularly those associated with biofilms, are challenging to treat due to an increased tolerance to commonly used antibiotics. This underscores the urgent need for innovative antimicrobial strategies. Here, we present an alternative simple-by-design approach focusing on the development of biocompatible and antibiotic-free nanocarriers from docosahexaenoic acid (DHA) that has the potential to combat microbial infections and phosphatidylglycerol (DOPG), which is attractive for use as a biocompatible prominent amphiphilic component of Gram-positive bacterial cell membranes. We assessed the anti-bacterial and anti-biofilm activities of these nanoformulations (hexosomes and vesicles) against S. aureus and S. epidermidis, which are the most common causes of infections on catheters and medical devices by different methods (including resazurin assay, time-kill assay, and confocal laser scanning microscopy on an in vitro catheter biofilm model). In a DHA-concentration-dependent manner, these nano-self-assemblies demonstrated strong anti-bacterial and anti-biofilm activities, particularly against S. aureus. A five-fold reduction of the planktonic and a four-fold reduction of biofilm populations of S. aureus were observed after treatment with hexosomes. The nanoparticles had a bacteriostatic effect against S. epidermidis planktonic cells but no anti-biofilm activity was detected. We discuss the findings in terms of nanoparticle-bacterial cell interactions, plausible alterations in the phospholipid membrane composition, and potential penetration of DHA into these membranes, leading to changes in their structural and biophysical properties. The implications for the future development of biocompatible nanocarriers for the delivery of DHA alone or in combination with other anti-bacterial agents are discussed, as novel treatment strategies of Gram-positive infections, including biofilm-associated infections.

SARS-CoV-2 inhibitory potential of fish oil-derived 2-pyrone compounds by acquiring linoleic acid binding site on the spike protein

Traditional medicines have reportedly treated SARS-CoV-2 infection. Substantial evidence shows that fish oil supplements promote human immune function, suggesting they may lessen susceptibility to SARS-CoV-2 infection and suppress viral replication by inducing interferon. Fish oil was subjected to partition chromatography and separated into two compounds (EP01 and DH01). Isolated compounds were purified and characterized using UV, FTIR, NMR, and mass spectrometry to confirm their identity. Molecular docking was studied on the SARS CoV-2 variants of concern; SARS CoV-2 WT (PDB: 6VXX), SARS CoV-2 Alpha variant (PDB: 7LWS), SARS CoV-2 Delta variant (PDB: 7TOU), SARS CoV-2 Gamma variant (PDB: 7V78), SARS CoV-2 Kappa variant (PDB: 7VX9), and SARS CoV-2 Omicron variant (PDB: 7QO7) and TMPRSS2 (PDB: 7Y0E). Further selected protein-ligand complexes were subjected to 100 ns MD simulations to predict their biological potential in the SARS-CoV-2 treatment. In-vitro biological studies were carried out to support in-silico findings. Isolated compounds EP01 and DH01 were identified as 5-Tridecyltetrahydro-2H-pyran-2-one and 5-Heptadecyltetrahydro-2H-pyran-2-one, respectively. The compound EP01 significantly reduced (93.24 %) the viral RNA copy number with an IC50 of ~8.661 μM. EP01 proved to be a potent antiviral by in-vitro method against the SARS-CoV-2 clinical isolate, making it a promising antiviral candidate, with a single dose capable of preventing viral replication.

Acellular fish skin grafts in the treatment of diabetic wounds: Advantages and clinical translation

Diabetic wounds cannot undergo normal wound healing due to changes in the concentration of hyperglycemia in the body and soon evolve into chronic wounds causing amputation or even death of patients. Diabetic wounds directly affect the quality of patients and social medical management; thus researchers started to focus on skin transplantation technology. The acellular fish skin grafts (AFSGs) are derived from wild fish, which avoids the influence of human immune function and the spread of the virus through low-cost decellularization. AFSGs contain a large amount of collagen and omega-3 polyunsaturated fatty acids and they have an amazing effect on wound regeneration. However, after our search in major databases, we found that there were few research trials in this field, and only one was clinically approved. Therefore, we summarized the advantages of AFSGs and listed the problems faced in clinical use. The purpose of this paper is to enable researchers to better carry out original experiments at various stages.

The gut microbiome-prostate cancer crosstalk is modulated by dietary polyunsaturated long-chain fatty acids

The gut microbiota modulates response to hormonal treatments in prostate cancer (PCa) patients, but whether it influences PCa progression remains unknown. Here, we show a reduction in fecal microbiota alpha-diversity correlating with increase tumour burden in two distinct groups of hormonotherapy naïve PCa patients and three murine PCa models. Fecal microbiota transplantation (FMT) from patients with high PCa volume is sufficient to stimulate the growth of mouse PCa revealing the existence of a gut microbiome-cancer crosstalk. Analysis of gut microbial-related pathways in mice with aggressive PCa identifies three enzymes responsible for the metabolism of long-chain fatty acids (LCFA). Supplementation with LCFA omega-3 MAG-EPA is sufficient to reduce PCa growth in mice and cancer up-grading in pre-prostatectomy PCa patients correlating with a reduction of gut Ruminococcaceae in both and fecal butyrate levels in PCa patients. This suggests that the beneficial effect of omega-3 rich diet is mediated in part by modulating the crosstalk between gut microbes and their metabolites in men with PCa.

Untargeted and temporal analysis of retinal lipidome in bacterial endophthalmitis

Bacterial endophthalmitis is a blinding infectious disease typically acquired during ocular surgery. We previously reported significant alterations in retinal metabolism during Staphylococcus (S) aureus endophthalmitis. However, the changes in retinal lipid composition during endophthalmitis are unknown. Here, using a mouse model of S. aureus endophthalmitis and an untargeted lipidomic approach, we comprehensively analyzed temporal alterations in total lipids and oxylipin in retina. Our data showed a time-dependent increase in the levels of lipid classes, sphingolipids, glycerolipids, sterols, and non-esterified fatty acids, whereas levels of phospholipids decreased. Among lipid subclasses, phosphatidylcholine decreased over time. The oxylipin analysis revealed increased prostaglandin-E2, hydroxyeicosatetraenoic acids, docosahexaenoic acid, eicosapentaenoic acid, and α-linolenic acid. In-vitro studies using mouse bone marrow-derived macrophages showed increased lipid droplets and lipid-peroxide formation in response to S. aureus infection. Collectively, these findings suggest that S. aureus-infection alters the retinal lipid profile, which may contribute to the pathogenesis of bacterial endophthalmitis.

Extraction, characterization, and therapeutic potential of Omega-3 fatty acids from Belone belone skin

This study provides the fatty acid profile, presence of Omega 3 fatty acids (ω3FAs) and therapeutic potential of the skin of Garfish (Belone belone), a highly nutritious fish. The ω3FAs were obtained using the urea crystallization method and confirmed by UV VIS spectroscopy, HPLC, FT-IR, and NMR. Additionally, the therapeutic potential of the ω3FAs was assessed through antioxidant, antimicrobial, antibiofilm, and toxicity assays. The oil extracted from Garfish skin (GS) predominantly contains ω3FAs, palmitic acids, and oleic acids. The ω3FAs exhibit high anti-free radical activity and ferric reducing activity. It reduces nitric oxide production as well as lipid peroxidation under certain time. They also demonstrate effective antibacterial activity against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Streptococcus pneumoniae. The biofilm formation is efficiently reduced by ω3FAs and eradication effects on biofilm are higher at 4000 µg/mL of concentration. When tested against brine shrimp larvae, ω3FAs were found to be non-toxic. The study indicates that GS skin oil contains a significant amount of omega-3 fatty acids and has potential therapeutic benefits due to its antioxidant and antibacterial properties, without causing any toxic effects. Omega-3 fatty acids have the potential to enhance the treatment of infections caused by harmful bacteria and their biofilm formation. Further research is needed to understand how omega-3 fatty acids work to kill bacteria and how they affect bacterial gene expression.

Marine Microalgae Schizochytrium sp. S31: Potential Source for New Antimicrobial and Antibiofilm Agent

BACKGROUND

The rise of antibiotic-resistant bacteria necessitates the discovery of new, safe, and bioactive antimicrobial compounds. The antibacterial and antibiofilm activity of microalgae makes them a potential candidate for developing natural antibiotics to limit microbial infection in various fields.

OBJECTIVE

This study aimed to analyze the antibacterial effect of the methanolic extract of Schizochytrium sp. S31 microalgae by broth microdilution and spot plate assays.

METHODS

The antibacterial effects of Schizochytrium sp. S31 extract was studied on gramnegative pathogens, Pseudomonas aeruginosa, Escherichia coli 35218, Klebsiella pneumonia, which cause many different human infections, and the gram-positive pathogen Streptococcus mutans. At the same time, the antibiofilm activity of the Schizochytrium sp. S31 extract on Pseudomonas aeruginosa and Escherichia coli 35218 bacteria were investigated by crystal violet staining method.

RESULTS

Schizochytrium sp. S31 extract at a 60% concentration for 8 hours displayed the highest antibacterial activity against P. aeruginosa, E. coli 35218, and K. pneumonia, with a decrease of 87%, 92%, and 98% in cell viability, respectively. The experiment with Streptococcus mutans revealed a remarkable antibacterial effect at a 60% extract concentration for 24 hours, leading to a notable 93% reduction in cell viability. Furthermore, the extract exhibited a dose-dependent inhibition of biofilm formation in P. aeruginosa and E. coli 35218. The concentration of 60% extract was identified as the most effective dosage in terms of inhibition.

CONCLUSION

This research emphasizes the potential of Schizochytrium sp. S31 as a natural antibacterial and antibiofilm agent with promising applications in the pharmaceutical sectors. This is the first study to examine the antibacterial activity of Schizochytrium sp. S31 microalgae using broth microdilution, spot plate assays, and the antibiofilm activity by a crystal staining method. The findings of this study show that Schizochytrium sp. S31 has antibacterial and antibiofilm activities against critical bacterial pathogens.

New Insights into Prospective Health Potential of ω-3 PUFAs

PURPOSE OF REVIEW

Docosahexaenoic acid and eicosapentaenoic acid are the two essential long-chain ω-3 polyunsaturated fatty acids (ω-3 PUFAs) promoting human health which are obtained from diet or supplementation. The eicosanoids derived from ω-6 and ω-3 PUFAs have opposite characteristics of pro- and anti-inflammatory activities. The proinflammatory effects of ω-6 PUFAs are behind the pathology of the adverse health conditions of PUFA metabolism like cardiovascular diseases, neurological disorders, and inflammatory diseases. A balanced ω-6 to ω-3 ratio of 1-4:1 is critical to prevent the associated disorders. But due to modern agricultural practices, there is a disastrous shift in this ratio to 10-20:1. This review primarily aims to discuss the myriad health potentials of ω-3 PUFAs uncovered through recent research. It further manifests the importance of maintaining a balanced ω-6 to ω-3 PUFA ratio.

RECENT FINDINGS

ω-3 PUFAs exhibit protective effects against diabetes mellitus-associated complications including diabetic retinopathy, diabetic nephropathy, and proteinuria. COVID-19 is also not an exception to the health benefits of ω-3 PUFAs. Supplementation of ω-3 PUFAs improved the respiratory and clinical symptoms in COVID-19 patients. ω-3 PUFAs exhibit a variety of health benefits including anti-inflammatory property and antimicrobial property and are effective in protecting against various health conditions like atherosclerosis, cardiovascular diseases, diabetes mellitus, COVID-19, and neurological disorders. In the present review, various health potentials of ω-3 PUFAs are extensively reviewed and summarized. Further, the importance of a balanced ω-6 to ω-3 PUFA ratio has been emphasized besides stating the diverse sources of ω-3 PUFA.

How to Select an Extracellular Matrix for Wound Repair: A Comprehensive Review

Background

An extracellular matrix (ECM) is a network of proteins and other molecules that provide support and structure to cells and tissues in the body. Since its discovery in 1930, researchers have reproduced the ECM through an array of evolving technologies, developing products that accelerate healing times, minimize scarring, and reduce pain. When selecting which ECM product to use, physicians rely on personal experience while considering wound location, type of tissue lost, exposed structures, chronicity, and even the patient's religious preferences. While comparison trials between a few different types of ECMs exist, there lacks a thorough investigation that assesses a majority of ECMs against each other.

Methods

Herein, we conducted a literature review using the PubMed database and utilized 71 articles to identify the best ECM for wound healing and positive patient outcomes. The primary search terms included extracellular matrix, xenograft, porcine, bovine, allograft, bioengineered matrix, acellularized fish skin, wounds, wound healing, and wound care. We did not exclude any specific type of research, but predominantly reviewed clinical trials, case series, and other review articles. We focused on the most popular and commonly used ECMs and constructed our results into the Table.

Results

We compared the indications, advantages, and disadvantages of each ECM and concisely illustrated these findings to provide a guide on how to select an ECM (Table). Allografts, whether they are glycerol or cryopreserved, suffice as a treatment choice and are superior to exposure healing. However, they do not produce healing at the same rate or quality as bioengineered matrices, porcine and bovine xenografts, or acellularized fish skin (AFS). Bioengineered matrices and porcine and bovine xenografts offer antimicrobial properties, low immunogenicity, cost effectiveness, and availability. The compromise with these ECMs is with healing times and cosmesis. Acellularized fish skin (AFS) provides diverse utility, antimicrobial activity, low immunogenicity, faster healing times, and cosmetic superiority. However, AFS yields a potential cost burden and is not plentiful or easily accessible in some parts of the world.

Conclusions

Our findings assist in removing the subjectivity component of selecting an ECM and suggest further comparison or head-to-head trials would yield a more algorithmic approach to wound healing. We suggest to consider implementing the Disabilities of the Arm, Shoulder, and Hand (DASH) score as an additional objective comparison method in these future trials.

Amoxicillin-docosahexaenoic acid encapsulated chitosan-alginate nanoparticles as a delivery system with enhanced biocidal activities against Helicobacter pylori and improved ulcer healing

Encapsulation of amoxicillin (AMX) for drug delivery against Helicobacter pylori infection and aspirin-induced ulcers in rat's stomachs was performed using docosahexaenoic acid (DHA)-loaded chitosan/alginate (CA) nanoparticles (NPs) developed by ionotropic gelation method. The physicochemical analyses of the composite NPs were performed by scanning electron microscopy, Fourier transform infrared spectroscopy, zeta potential, X-ray diffraction, and atomic force microscopy. The encapsulation efficiency of AMX was increased to 76% by incorporating DHA, which resulted in a reduction in the particle size. The formed CA-DHA-AMX NPs effectively adhered to the bacteria and rat gastric mucosa. Their antibacterial properties were more potent than those of the single AMX and CA-DHA NPs as demonstrated by the in vivo assay. The composite NPs attained higher mucoadhesive potential during food intake than during fasting (p = 0.029). At 10 and 20 mg/kg AMX, the CA-AMX-DHA showed more potent activities against H. pylori than the CA-AMX, CA-DHA, and single AMX. The in vivo study showed that the effective dose of AMX was lower when DHA was included, indicating better drug delivery and stability of the encapsulated AMX. Both mucosal thickening and ulcer index were significantly higher in the groups receiving CA-DHA-AMX than in the groups receiving CA-AMX and single AMX. The presence of DHA declines the pro-inflammatory cytokines including IL-1β, IL-6, and IL-17A. The synergistic effects of AMX and the CA-DHA formulation increased the biocidal activities against H. pylori infection and improved ulcer healing properties.

Antibiofilm Activity of Omega-3 Fatty Acids and Its Influence on the Expression of Biofilm Formation Genes on Staphylococcus aureus

Background: Currently, 1–2% of all prosthetic joint surgeries are followed by an infection. These infections cause approximately 4% of deaths in the first year after surgery, while the 5-year mortality rate is up to 21%. Prosthetic joint infections are mainly caused by Staphylococcus aureus or Staphylococcus epidermis strains. Both species share the capability of biofilm formation and methicillin resistance. The formation of biofilm helps bacterial cells to withstand critical environmental conditions. Due to their tolerance against antibacterial substances, biofilms are a significant problem in modern medicine. Alternatives for the use of methicillin as a therapeutic are not yet widespread. The use of omega-3 fatty acids, such as docosahexaenoic acid, may help against prosthetic joint infections and lower mortality rates. The aim of this study is to evaluate if docosahexaenoic acid offers a safe anti-biofilm activity against Staphylococcus aureus and MRSA without enhancing icaADBC-dependent biofilm formation or additional stress responses, therefore enhancing antibiotic tolerance and resistance. Methods: In this study, we examined the gene expression of biofilm-associated genes and regulators. We performed RT-qPCR after RNA extraction of Staphylococcus aureus ATCC 29213 and one clinical MRSA strain. We compared gene expression of icaADBC, SarA, SigB, and agrAC under the influence of 1.25 mg /L and 0.625 mg/L of docosahexaenoic acid to their controls. Results: We found a higher expression of regulatory genes such as SarA, SigB, agrA, and agrC at 1.25 mg/L of docosahexaenoic acid in ATCC 29213 and a lower increase in gene expression levels in clinical MRSA isolates. icaADBC was not affected in both strains at both concentration levels by docosahexaenoic acid. Conclusions: Docosahexaenoic acid does not enhance icaADBC-dependent biofilm formation while still reducing bacterial CFU in biofilms. Docosahexaenoic acid can be considered an option as a therapeutic substance against biofilm formation and may be a good alternative in reducing the risk of MRSA formation.

Hydrolysis of Edible Oils by Fungal Lipases: An Effective Tool to Produce Bioactive Extracts with Antioxidant and Antimicrobial Potential

Hydrolysis of olive, rapeseed, linseed, almond, peanut, grape seed and menhaden oils was performed with commercial lipases of Aspergillus niger, Rhizopus oryzae, Rhizopus niveus, Rhizomucor miehei and Candida rugosa. In chromogenic plate tests, olive, rapeseed, peanut and linseed oils degraded well even after 2 h of incubation, and the R. miehei, A. niger and R. oryzae lipases exhibited the highest overall action against the oils. Gas chromatography analysis of vegetable oils hydrolyzed by R. miehei lipase revealed about 1.1 to 38.4-fold increases in the concentrations of palmitic, stearic, oleic, linoleic and α-linolenic acids after the treatment, depending on the fatty acids and the oil. The major polyunsaturated fatty acids produced by R. miehei lipase treatment from menhaden oil were linoleic, α-linolenic, hexadecanedioic, eicosapentaenoic, docosapentaenoic and docosahexaenoic acids, with yields from 12.02 to 52.85 µg/mL reaction mixture. Folin-Ciocalteu and ferric reducing power assays demonstrated improved antioxidant capacity for most tested oils after the lipase treatment in relation to the concentrations of some fatty acids. Some lipase-treated and untreated samples of oils, at 1.25 mg/mL lipid concentration, inhibited the growth of food-contaminating bacteria. The lipid mixtures obtained can be reliable sources of extractable fatty acids with health benefits.

Antimicrobial Activity of Lipid Extracts of Echinoderms in the Nhatrang Bay (South China Sea)

The obtained results on the study of the antimicrobial activity of lipid extracts of tissues of starfishes Linckia laevigata and Culcita novaeguineae and sea urchin Diadema setosum collected in the Nhatrang Bay (South China Sea) against nosocomial strains of Klebsiella pneumoniae, Enterococcus faecium, Escherichia coli, Pseudomonas aeruginosa, Candida sp., Streptococcus pyogenes, and Staphylococcus aureus are presented. The effect of the investigated extracts on Gram-positive, Gram-negative microorganisms, as well as yeast of the genus Candida, was determined. It was found that lipid extracts of echinoderms of the Nhatrang Bay exhibit the highest antimicrobial activity against the Gram-positive microorganisms, namely Streptococcus pyogenes.

Microalgae and Cyanobacteria Strains as Producers of Lipids with Antibacterial and Antibiofilm Activity

Lipids are one of the primary metabolites of microalgae and cyanobacteria, which enrich their utility in the pharmaceutical, feed, cosmetic, and chemistry sectors. This work describes the isolation, structural elucidation, and the antibiotic and antibiofilm activities of diverse lipids produced by different microalgae and cyanobacteria strains from two European collections (ACOI and LEGE-CC). Three microalgae strains and one cyanobacteria strain were selected for their antibacterial and/or antibiofilm activity after the screening of about 600 strains carried out under the NoMorFilm European project. The total organic extracts were firstly fractionated using solid phase extraction methods, and the minimum inhibitory concentration and minimal biofilm inhibitory concentration against an array of human pathogens were determined. The isolation was carried out by bioassay-guided HPLC-DAD purification, and the structure of the isolated molecules responsible for the observed activities was determined by HPLC-HRESIMS and NMR methods. Sulfoquinovosyldiacylglycerol, monogalactosylmonoacylglycerol, sulfoquinovosylmonoacylglycerol, α-linolenic acid, hexadeca-4,7,10,13-tetraenoic acid (HDTA), palmitoleic acid, and lysophosphatidylcholine were found among the different active sub-fractions selected. In conclusion, cyanobacteria and microalgae produce a great variety of lipids with antibiotic and antibiofilm activity against the most important pathogens causing severe infections in humans. The use of these lipids in clinical treatments alone or in combination with antibiotics may provide an alternative to the current treatments.

Assessment of Antibiofilm Potencies of Nervonic and Oleic Acid against Acinetobacter baumannii Using In Vitro and Computational Approaches

Acinetobacter baumannii is a nosocomial pathogen, and its biofilms are tolerant to desiccation, nutrient starvation, and antimicrobial treatment on biotic and abiotic surfaces, tissues, and medical devices. Biofilm formation by A. baumannii is triggered by a quorum sensing cascade, and we hypothesized that fatty acids might inhibit its biofilm formation by interfering with quorum sensing. Initially, we investigated the antibiofilm activities of 24 fatty acids against A. baumannii ATCC 17978 and two clinical isolates. Among these fatty acids, two unsaturated fatty acids, nervonic and oleic acid, at 20 μg/mL significantly inhibited A. baumannii biofilm formation without affecting its planktonic cell growth (MICs were >500 μg/mL) and markedly decreased the motility of A. baumannii but had no toxic effect on the nematode Caenorhabditis elegans. Interestingly, molecular dynamic simulations showed that both fatty acids bind to the quorum sensing acyl homoserine lactone synthase (AbaI), and decent conformational stabilities of interactions between the fatty acids and AbaI were exhibited. Our results demonstrate that nervonic and oleic acid inhibit biofilm formation by A. baumannii strains and may be used as lead molecules for the control of persistent A. baumannii infections.