AStreptomyces lusitanusDMZ-3 strain with potential to synthesize both insoluble and soluble melanins was detected. Melanins are quite distinguished based on their solubility for varied biotechnological applications. The present investigation reveals the enhanced production of insoluble and soluble melanins in tyrosine medium by a single culture.Streptomyces lusitanusDMZ-3 was characterized by 16S rRNA gene analysis. An enhanced production of 5.29 g/L insoluble melanin was achieved in a submerged bioprocess following response surface methodology. Combined interactive effect of temperature (50°C), pH (8.5), tyrosine (2.0 g/L), and beef extract (0.5 g/L) were found to be critical variables for enhanced production in central composite design analysis. An optimized indigenous slant culture system was an innovative approach for the successful production (264 mg/L) of pure soluble melanin from the droplets formed on the surface of the culture. Both insoluble and soluble melanins were confirmed and characterized by Chemical, reactions, UV, FTIR, and TLC analysis. First time, cytotoxic study of melanin using brine shrimps was reported. Maximum cytotoxic activity of soluble melanin was Lc₅₀-0.40 µg/mL and insoluble melanin was Lc₅₀-0.80 µg/mL.

Antibiotic-resistant bacteria causing foodborne serious illnesses can be found in contaminated food. Therefore, this study aimed to identify the pathogens, genes, and antimicrobial residues present in raw milk and meat. We collected 40 raw milk and 40 beef samples using the aseptic method from various parts of the Faisalabad metropolis, Pakistan. The samples were cultured on blood, MacConkey, and UTI chrome agar. The VITEK 2 compact system was used for microbial identification and determination of minimum inhibitory concentrations. Antimicrobial resistance genes for extended-spectrum β-lactamases, methicillin resistance in Staphylococcus aureus, and carbapenem resistance were identified using molecular techniques. ELISA was used to determine the tetracycline residue level in each sample. The beef samples showed polymicrobial contamination with 64 bacterial isolates, with Escherichia coli (29; 45.3%) and Klebsiella pneumoniae (11; 17.1%) predominating. The milk samples showed polymicrobial contamination with 73 bacterial isolates, with E. coli (22; 30%), K. pneumoniae (12; 16.4%), and S. aureus (10; 13.6%) forming the majority. Twenty-eight (43.7%) isolates from beef harbored tet genes, nineteen (29.6%) bla_CTX-M, and fourteen (21.8%) bla_NDM-1, and twenty-six (35.6%) isolates from milk harbored tet genes, nineteen (26%) bla_TEM and bla_CTX-M, and three (4%) bla_NDM-1. Twenty-two (55%) each of the beef and milk samples exceeded the maximum residue limit for tetracycline. Polymicrobial contamination by bacteria possessing bla_CTX-M, bla_TEM, bla_NDM-1, bla_OXA, mecA, and tet genes was identified in food samples. The high tetracycline residue levels pose a serious health risk to consumers.

Paper biosensor was developed using Tyr-AuNps bioconjugate produced byStreptomycesfor the detection of phenol from the effluent of wine, paper, and plastic industries. Among three filter papers assessed, Whatman number 2 filter paper was proved to be the best paper base for the development of biosensor. Tyrosinase and gold nanoparticles being produced by a single novel isolateStreptomyces tuirusDBZ39 proved to be efficient bioconjugate for the detection of phenol constituents, due to its biocompatibility. The substrate specific catalytic activity of the tyrosinase and unique Surface Plasmon Resonance attribute of gold nanoparticles are the cause for efficient detection of phenol constituents from the effluent of wine, paper, and plastic industries in 3 min. The different types and quantity of phenolic constituents in various industrial effluents, such as phenol in wine, dopamine in paper, and catechol in plastic effluents, were accurately detected by the bioconjugate. The efficacy of tyrosinase in the detection of phenol constituents was expected to be enhanced by the gold nanoparticles because of their electron, optical, and magnetic properties. This novel paper strip biosensor could be cost-effective and efficient means of future devices for the detection of phenolic pollutants from any environmental samples.

Background: The global spread of extended‐spectrum beta‐lactamase (ESBL)‐producing and carbapenem‐resistant Enterobacterales (CRE) poses a significant concern. Acquisition of antimicrobial resistance genes leads to resistance against several antibiotics, limiting treatment options. We aimed to study ESBL‐producing and CRE transmission in clinical settings.Methods: From clinical samples, 227 ESBL‐producing and CRE isolates were obtained. The isolates were cultured on bacterial media and confirmed by VITEK 2. Antibiograms were tested against several antibiotics using VITEK 2. The acquired resistance genes were identified by PCR.Results: Of the 227 clinical isolates, 145 (63.8%) were Klebsiella pneumoniae and 82 (36.1%) were Escherichia coli; 76 (33.4%) isolates were detected in urine, 57 (25.1%) in pus swabs, and 53 (23.3%) in blood samples. A total of 58 (70.7%) ESBL‐producing E. coli were resistant to beta‐lactams, except for carbapenems, and 17.2% were amikacin‐resistant; 29.2% of E. coli isolates were resistant to carbapenems. A total of 106 (73.1%) ESBL‐producing K. pneumoniae were resistant to all beta‐lactams, except for carbapenems, and 66.9% to ciprofloxacin; 38 (26.2%) K. pneumoniae were resistant to carbapenems. Colistin emerged as the most effective antibiotic against both bacterial types. Twelve (20.6%) E. coli isolates were positive for bla_CTX‐M, 11 (18.9%) for bla_TEM, and 8 (33.3%) for bla_NDM. Forty‐six (52.3%) K. pneumoniae isolates had bla_CTX‐M, 27 (18.6%) bla_TEM, and 26 (68.4%) bla_NDM.Conclusion: This study found a high prevalence of drug‐resistant ESBL‐producing and CRE, highlighting the need for targeted antibiotic use to combat resistance.