A biosurfactant-producing fungal strain, Exophiala spinifera CSF123, was isolated from cashew oil-contaminated soil. Internal transcribed spacer sequencing followed by phylogenetic analysis revealed that the isolated fungus shared 98.42% similarity with E. spinifera CBS66.76. The biosurfactant molecule, named ES-414, produced by the fungus was purified to homogeneity by HPLC, and subsequent electrospray mass spectrometric analysis showed that its neutral mass is 414 Da. The molecule displayed remarkable antibiofilm activity. At concentrations of 15 and 80 μg/mL, ES-414 showed 62.17% biofilm inhibition against Candida tropicalis and 66% inhibition against Candida albicans, respectively. It also displayed significant antifungal properties against C. albicans, C. tropicalis, Candida glabrata, Candida parapsilosis, and Candida krusei. ES-414, in a dose-dependent manner, inhibited the quorum sensing activity of Chromobacterium violaceum. Thermogravimetric analysis of ES-414 indicated that the molecule remains stable up to 240°C. Detailed structural characterization using GC-MS, FTIR, UV-visible spectroscopy, elemental analysis, Molisch test, TLC analysis, and solubility studies indicated that ES-414 is a glycolipid-like molecule.

The mammalian immune system has evolved in constant dialogue with its diverse microbiota, forming an ecological and molecular partnership that is fundamental to health. This review examines how microbial communities shape immunity across developmental and functional axes, the immunological consequences of dysbiosis during infection and inflammatory disease, and emerging microbiota-targeted interventions. The host–microbiota–pathogen triad offers a framework to understand how commensals and pathogens compete for ecological niches and immune recognition, and how disturbances in this balance can cascade into chronic inflammation or infection. Microbial metabolites such as short-chain fatty acids, secondary bile acids, and tryptophan derivatives act as key bioactive intermediaries translating microbial activity into host immune architecture, influencing epigenetic programming, cellular differentiation, and mucosal barrier function. These interactions orchestrate tolerance toward commensals while maintaining effector readiness against pathogens, particularly through regulatory T cell (Treg)–Th17 balance, B cell education, and Immunoglobulin A (IgA) responses. When perturbed, as in infections caused by Clostridioides difficile, Klebsiella pneumoniae, Salmonella enterica, or Listeria monocytogenes, the ensuing dysbiosis reinforces immune dysfunction in a self-perpetuating cycle. Therapeutic frontiers now extend beyond conventional antimicrobial strategies to include live biotherapeutics, bacteriophage therapy, fecal microbiota transplantation, and metabolite-based (postbiotic) interventions. Future efforts must reconcile inter-individual microbiome variability with precision medicine, integrating metagenomic and metabolomic profiling to design safe, effective, and personalized microbiota-centered therapeutics.

Microbial spoilage by Pseudomonas fluorescens and Pseudomonas putida remains a critical challenge in the dairy industry, particularly in refrigerated environments, where traditional preservation methods face limitations. This study demonstrates the biocontrol potential of P. fluorescens and P. putida-specific novel bacteriophages, AM.PF and AM.PP. Phage characterization confirmed them as safe, lytic dsDNA phages devoid of antimicrobial resistance genes, toxins or lysogenic markers, exhibiting stability across wide pH (3–11) and temperature (4°C–70°C) ranges. Both phages inhibited biofilm formation (83% and 77%) and disrupted established biofilms (42% and 54%). When phages were encapsulated in a 12% gelatin matrix, sustained release reached 77% (AM.PF) and 70% (AM.PP). Notably, the bioactive gelatin coatings reduced P. fluorescens and P. putida by 92% and 89% on cheese surfaces and by 48.8% and 92.5% in refrigerated milk, respectively. These findings demonstrate that phage-incorporated biomaterials offer a safe, highly effective strategy for food preservation.

Invasive fungal diseases (IFDs) are a global health threat, especially among immunocompromised populations, due to their high mortality rates and the increasing prevalence of antifungal resistance. In recognition of this threat, the World Health Organization (WHO) has designated Cryptococcus neoformans, Candida auris, Aspergillus fumigatus, and Candida albicans as critical-priority fungal pathogens. During host infection, host-derived reactive oxygen species (ROS) function as potent antimicrobial molecules, whereas fungal-derived ROS act as intracellular signaling mediators regulating oxidative stress adaptation, metabolism, virulence, and antifungal tolerance. Although oxidative stress responses have been extensively investigated in individual fungal pathogens, a comprehensive comparative analysis of oxidative stress signaling across these critical fungal pathogens remains limited. This review systematically compares oxidative stress sensing and signaling networks in the four WHO critical-priority fungal pathogens and classifies oxidative stress-associated pathways into conserved, and species-specific regulatory mechanisms. Conserved pathways, including HOG-MAPK, calcineurin, cAMP-PKA, cell wall integrity, and thioredoxin-dependent signaling, are discussed alongside pathogen-specific adaptations that promote biofilm formation, capsule and melanin production, polarized growth, morphogenesis, immune evasion, and antifungal resistance. By integrating conserved and divergent oxidative stress signaling mechanisms, this review provides a comparative framework that advances our understanding of fungal pathogenesis and highlights potential targets for the development of broad-spectrum and species-specific antifungal therapies.

Candida albicans is a deadly fungal pathogen, particularly in immunocompromised individuals, where a simple superficial infection rapidly transforms into life-threatening systemic candidiasis. Virulence factors of C. albicans include the yeast-to-hyphae transition, biofilm formation, and protease production, which are crucial for establishing infection. Targeting virulence factors is a promising strategy to combat C. albicans infections, which can overcome the limitations of conventional treatment modalities. Essential oils are important in this regard as they are used in traditional medicine due to their antimicrobial capabilities. This study is focused on the antivirulent activity of cumin essential oil (CEO), which significantly reduced the key virulence factors of C. albicans, such as germ tube formation and protease production. A subinhibitory concentration (0.015% v/v) of CEO downregulated the expression of the HWP1, ALS3, and RAS1 genes involved in regulating virulence. In silico studies demonstrated that major compounds of CEO interacted with key amino acid residues of secreted aspartyl proteases (Sap4, Sap5, Sap6) and heat shock protein (Hsp90), a regulator of hyphal formation. CEO significantly reduced biofilm formation of C. albicans in different simulated body fluids such as saliva, artificial urine, and tear fluid. Furthermore, CEO affected the host-pathogen interaction of C. albicans with THP-1 macrophages by increasing phagocytosis and inhibiting germ tube formation. Additionally, CEO treatment modulated the levels of pro-inflammatory and anti-inflammatory cytokines, suggesting that CEO also has immunomodulatory properties, in addition to its antivirulence activity. These results indicate that CEO could be a promising candidate for combating C. albicans infections.

Pathogenic bacteria exploit host cells by interfering with the signalling pathways in several ways. Pasteurella multocida, a gram-negative coccobacillus, occurs as a commensal in humans and animals and causes various diseases in ungulates by surviving inside the host cells. P. multocida toxin (PMT) was reported to be one of the most potent mitogens that possess tumour-promoting properties. The present study examined the mitogenic potential of P. multocida cell lysate and culture supernatant on fibrosarcoma cells (HT1080). Matrix metalloproteinase-2 (MMP-2) and Matrix metalloproteinase-9 (MMP-9) activity were significantly induced in the presence of P. multocida cell lysate, culture supernatant and in co-culture conditions. Downregulation of endogenous inhibitors of MMP like Tissue Inhibitor of Metalloproteinases (TIMP-2) and reversion inducing cysteine rich protein with kazal motifs (RECK) was also observed. Significant induction of mitogenic and cell survival pathways like p44/42MAPK and Akt was observed in the presence of bacterial components. A pronounced increase in migration and invasion of HT1080 was observed with bacterial cell lysate and culture supernatant. Treatment with plumbagin, a natural naphthoquinone from the medicinal plant Plumbago zeylanica, demonstrated significant cell death in HT1080. In the presence of culture supernatant and cell lysate of P. multocida, the cell death induced by plumbagin was reduced indicating the role of the bacterial components in promoting the proliferation of cells. Therefore, the present study confirms the role of bacterial infections in promoting the proliferation of cancer cells or worsening existing cancers, thereby emphasizing the need for novel perspectives in developing therapies to combat such infections effectively.

Pyomelanogenic P. aeruginosa, frequently isolated from patients with urinary tract infections and cystic fibrosis, possesses the ability to withstand oxidative stress, contributing to virulence and resulting in persistent infections. Whole genome sequence analysis of U804, a pyomelanogenic, multidrug-resistant, clinical isolate, demonstrates the mechanism underlying pyomelanin overproduction. Seven essential oils (EOs) were screened for pyomelanin inhibition. Garlic, cinnamon and thyme EOs were selected for further studies based on their significant anti-virulent properties, like inhibition of pyomelanin production and biofilm formation. Additionally, downregulation of the expression of virulence genes regulated by quorum sensing (QS) and a decrease in levels of the QS signaling molecule, C12-HSL, were also observed. The EO treatment inhibited the survival of U804 in human blood and increased survival of C. elegans, a whole animal model of pathogenesis. EO treatment also resulted in a significant reduction of efflux pump activity, indicative of their effect on antibiotic sensitization. Garlic oil enhanced the permeability of the bacterial membrane, resulting in decreased survival, when combined with sub-MIC concentrations of colistin. This study demonstrates that thyme, cinnamon and garlic EOs can attenuate pyomelanogenic P. aeruginosa virulence traits. Additionally, garlic potentiates drug sensitivity, suggesting its promising therapeutic use in combating pyomelanogenic MDR infections.

This research focuses on designing a novel, five-layered N95 mask fabric that integrates the natural antimicrobial properties of Boswellia serrata, thereby unlocking a new dimension in respiratory protection. Specifically, the second and third layers of the mask fabric were coated with a chloroform extract of Boswellia serrata to impart layer-specific functionality. The functionalized mask fabrics underwent rigorous analysis, including Scanning Electron Microscopy (SEM), Energy Dispersive X-ray (EDX) Spectroscopy, Fourier Transform Infrared Spectroscopy (FTIR), and wettability measurements, confirming the successful incorporation of the extract. The contact killing assay demonstrated a highly effective dual-action defense system. The extract-coated second layer exhibited a rapid, but transient, antimicrobial effect, showing excellent inhibition within one hour (92% against S. aureus, 86% against E. aerogenes), though this effect diminished significantly by eight hours. In contrast, the third layer provided a prolonged and sustained antimicrobial effect, maintaining high inhibition even after eight hours (100% against C. albicans and K. pneumoniae, and 90% against E. aerogenes). Maximum killing efficiency was observed at four hours for both layers. This innovative application of layer-specific engineering offers enhanced and prolonged protection against airborne pathogens, marking a significant leap in mask technology.

The global rise in multidrug-resistant (MDR) Klebsiella pneumoniae, a critical ESKAPE pathogen, has outpaced the development of effective antibiotics. Bacteriophage therapy offers a promising alternative, but therapeutic candidates must be carefully selected for broad activity, genetic safety, synergistic cocktail performance, and clinical stability. We isolated and characterized six novel lytic phages (vB_Kpn_AM.K1 to vB_Kpn_AM.K6) targeting K. pneumoniae by assessing morphology, host range, growth kinetics, physicochemical stability, and resistance frequency. Genomes were sequenced to confirm absence of lysogeny and virulence genes. Infection dynamics was visualized via fluorescence microscopy. Phage activity was tested across 60 different MDR K. pneumoniae clinical isolates, obtained from diverse sources such as blood, sputum, occult feces, urine etc. All six isolated phages were identified as novel dsDNA phages belonging to Caudoviricetes, with genome sizes ranging from 111 to 169 Kbp, devoid of virulence and AMR genes and demonstrating strong bacteriolytic activity. Growth kinetics indicated burst sizes varying from 12-148 PFU/infected cell. The phages displayed stability between 4-50°C, pH 4 -10 and sustained complete activity after lyophilization. More significantly, the phages and their cocktail combinations could effectively kill 93

Sequence-defined polymers have emerged as a unique class of macromolecules with precisely controlled monomer sequences. Despite advances, precise sequence control in synthetic oligomers remains elusive. In the present study, we report a novel approach for the efficient production of sequence-defined peptoid oligomers (SDO) without support for the first time. The proposed strategy provides several advantages, including efficient, iterative, scalable, support-free, and protection-deprotection-free synthesis of glycine-based peptoids. It also provides a facile postsynthetic modification that enables the design of a novel SDO framework incorporating diverse amine groups, yielding versatile platforms with broad applications. This approach is based on a tunable comonomer, chloroacetyl chloride, utilizing a commercially available reactive amine derivative, forming a chloro-terminal amide scaffold, which can be employed for the synthesis of oligomers without chromatographic purification. This viable approach enabled us to perform high-speed synthesis of sequence-defined peptoid oligomers with five monomer sequences in 9 h. As a proof-of-concept method, we incorporated various alkyl and aryl moieties into sequence-defined oligomers at precise sites. Our SDO platform has achieved two key developments: (i) innovative postsynthetic modification strategies and (ii) single-step chain length extension. The resulting compounds were comprehensively screened for potential bioactive properties, displaying promising biological properties, against both bacterial and fungal strains. Such findings highlight the strong potential of our platform to generate oligomeric structures with therapeutic relevance, particularly as next-generation antimicrobial and antifungal candidates. Further, SAR studies with in silico analysis on peptoids enable us to discover interesting findings on biological properties.

The rapid emergence of drug resistant pathogens is a major threat which has warranted the development of alternative strategies to combat infectious diseases. In this work, we have tested the anti-virulent activity of Meldrum’s acid activated furan (MAF) and 1,3-dimethyl barbituric acid activated furan (BAF) against Chromobacterium violaceum and Pseudomonas aeruginosa. It was found that MAF significantly reduced the violacein production and biofilm formation of C. violaceum at sub-inhibitory concentrations. The quorum sensing (QS) regulated virulence factors of P. aeruginosa including biofilm formation, motility, pigment production, and elastase activity were also found to be reduced considerably at sub-inhibitory concentrations of MAF. Additionally, MAF downregulated the expression of genes in the QS circuitry of P. aeruginosa, demonstrating the potential of MAF in lowering the pathogenicity of P. aeruginosa. In silico studies demonstrated the potential of MAF to compete with the signaling molecules of C. violaceum and P. aeruginosa for the QS receptor interaction. In vivo studies using Caenorhabditis elegans demonstrated the anti-pathogenicity of MAF by enhancing the survival of P. aeruginosa-infected C. elegans. These results suggest that activated furan compounds could be potential inhibitors of QS-mediated virulence factors in C. violaceum and P. aeruginosa, encouraging their use in combating multidrug-resistant pathogens.

In India, multidrug resistance determinants are much more abundant in community-associated bacterial pathogens due to the improper treatment of domestic and industrial effluents. In particular, a high bacterial load of the opportunistic pathogen P. aeruginosa in sewage and water bodies in India is well documented.

Earlier studies from our laboratory have demonstrated that clove bud oil (CBO) attenuates expression of certain virulence factors of Pseudomonas aeruginosa PAO1. Here, we probe more deeply into the effect of CBO on four pseudomonal proteases - elastase A, elastase B, protease IV and alkaline protease - each known to play key roles in disease pathogenesis. CBO inhibited the activity of these proteases present in the bacterial culture supernatant. Zymography studies indicated that these proteases can activate host matrix metalloproteases (MMPs) to establish infection, through conversion of pro-MMP-2 to active MMP-2. PAO1 is a predominant pathogen in burn wound infections and we show the modulatory effect of CBO on MMPs in an in vitro model of burn injury. Furthermore, CBO induced dose-dependent neutrophil extracellular trap formation in human neutrophils. CBO also increased the survival of C . elegans infected with PAO1, establishing an anti-infective role in a whole animal model of pathogenesis. LC-MS/MS analysis indicated that CBO treatment elicited a significant reduction of signalling molecules (Acyl-Homoserine-Lactone) involved in quorum sensing regulation. Our observations demonstrate that CBO attenuates key virulence mechanisms of this important human pathogen, while concomitantly enhancing host innate immunomodulatory functions, with potential implications for topical therapy against antibiotic-resistant infections.

Quorum sensing (QS), a communication system involved in virulence of pathogenic bacteria like Pseudomonas aeruginosa is a promising target to combat multiple drug resistance. In vitro studies using clove bud oil (CBO) in P. aeruginosa revealed a concentration dependent attenuation of a variety of virulence factors including motility, extracellular DNA, exopolysaccharides and pigment production. Furthermore, treatment with CBO demonstrated a distinct dose-dependent reduction in biofilm formation as well as promoting dispersion of already formed biofilm, observations that were also supported by porcine skin ex vivo studies. Expression studies of genes involved in signalling systems of P. aeruginosa indicated a specific decrease in transcription of pqsA , but not in the lasI or rhlI levels. Additionally, the expression of vfr and gacA genes, involved in regulation, was also not affected by CBO treatment. CBO also influenced the PQS signalling pathway by decreasing the levels of kynurenine, an effect which was reversed by the addition of exogenous kynurenine. Though the synthesis of the signalling molecules of the Las and Rhl pathways was not affected by CBO, their activity was significantly affected, as observed by decrease in levels of their various effectors. Molecular modelling studies demonstrated that eugenol, the major component of CBO, favourably binds to the QS receptor by hydrophobic interactions as well as by hydrogen bonding with Arg61 and Tyr41 which are key amino acid residues of the LasR receptor. These results thus elucidate the molecular mechanism underlying the action of CBO and provide the basis for the identification of an attractive QS inhibitor.

Objective: The present study attempted to evaluate the anti-biofilm activity of D-amino acids (D-AAs) on Pseudomonas aeruginosa and determine if the combination of D-AAs with tetracycline enhances the anti-biofilm activity in vitro and ex vivo.Methods: Different D-AAs were tested for antibiofilm activity against wild type P. aeruginosa PAO1 and two multidrug resistant P. aeruginosa clinical strains in the presence of sub inhibitory concentrations of tetracycline using crystal violet microtitre plate assay. Results were further validated using in vitro wound dressing and ex vivo porcine skin models followed by cytotoxicity and hemocompatibility studies.Results: D-tryptophan (5 mmol) showed 61 % reduction in biofilm formation of P. aeruginosa. Interestingly combinatorial effect of 5 mmol D-tryptophan and 0.5 minimum inhibitory concentration (MIC) (7.5µg/ml) tetracycline showed 90% reduction in biofilm formation. 5 mmol D-methionine shows 28 % reduction and combination with tetracycline shows 41% reduction in biofilm formation of P. aeruginosa. D-leucine and D-tyrosine alone or in combination with tetracycline did not show significant anti-biofilm activity. D tryptophan-tetracycline combination could reduce 80 % and 77 % reduction in biofilm formation in two multi drug resistant P. aeruginosa clinical strains. D-tryptophan-tetracycline-combination could also reduce 76% and 66% reduction in biofilm formation in wound dressing model and porcine skin explant respectively. The cytotoxicity and hemocompatibility studies did not show significant toxicity when this combination was used.Conclusion: The results established the potential therapeutic application of D-tryptophan alone or in combination with tetracycline for treating biofilm associated clinical problems caused by P. aeruginosa.

To investigate reversibility of ethanol induced testicular injuries on treatment with L-ornithine-L-aspartate, male Wistar rats were treated with ethanol (1.6g/kg b.wt/day) and L-ornithine- L-aspartate (200mg/kg b.wt/ day) for 4 weeks. L-ornithine-L-aspartate effectively prevented the ethanol induced body and testes weight reduction; changes in testicular weight well correlated with body weight. Drug exhibited an ability to counteract ethanol induced oxidative challenge as it effectively reduced testicular TBARS and increased tissue ascorbic acid, GSH and activities of superoxide dismutase, catalase, GSH-Red and Se-GSH-Px. However the drug didn't show promising effect on inhibitory effect of ethanol on testicular D5, 3-beta and 17-beta HSD (hydroxy steroid dehydrogenase).

INTRODUCTION:Mobile phones have become indispensable in the daily lives of men and women around the globe. As cell phone use has become more widespread, concerns have mounted regarding the potentially harmful effects of RF-EMR from these devices.OBJECTIVE:The present study was designed to evaluate the effects of RF-EMR from mobile phones on free radical metabolism and sperm quality.MATERIALS AND METHODS:Male albino Wistar rats (10-12 weeks old) were exposed to RF-EMR from an active GSM (0.9/1.8 GHz) mobile phone for 1 hour continuously per day for 28 days. Controls were exposed to a mobile phone without a battery for the same period. The phone was kept in a cage with a wooden bottom in order to address concerns that the effects of exposure to the phone could be due to heat emitted by the phone rather than to RF-EMR alone. Animals were sacrificed 24 hours after the last exposure and tissues of interest were harvested.RESULTS:One hour of exposure to the phone did not significantly change facial temperature in either group of rats. No significant difference was observed in total sperm count between controls and RF-EMR exposed groups. However, rats exposed to RF-EMR exhibited a significantly reduced percentage of motile sperm. Moreover, RF-EMR exposure resulted in a significant increase in lipid peroxidation and low GSH content in the testis and epididymis.CONCLUSION:Given the results of the present study, we speculate that RF-EMR from mobile phones negatively affects semen quality and may impair male fertility.

Ethanol intoxication resulted in high extent of lipid peroxidation, and reduction in antioxidant defenses (decreased GSH, GSH/GSSG ratio, and catalase, SOD and GPx activities) and (Na+/K+)-ATPase activity in kidney. Alpha-tocopherol treatment effectively protected kidney from ethanol induced oxidative challenge and improved renal (Na+/K+)-ATPase activity. Ethanol induced oxidative stress in the kidney and decreased (Na+/K+)-ATPase activity could be reversed by treatment with ascorbic acid.

Evidence of increased oxidative stress in patients of osteoarthritis in comparison with healthy control subjects was investigated by measuring the thiobarbituric acid reactive substances (TBARS), vitamin C, reduced glutathione (GSH) and the activities of superoxide dismutase (SOD), catalase and glutathione peroxidase (GPx) in erythrocytes. It was observed that osteoarthritis patients were more susceptible to oxidative damage than controls as evident from increased TBARS and decreased ascorbic acid, GSH, catalase and GPx in erythrocytes. Significant increase in SOD activity found in patients might be an adaptive response. With the understanding of the role of antioxidants in arthritis, it is becoming increasingly clear that these agents seem to be beneficial in osteoarthritis.