The use of natural products isolated from mushrooms against infection, cancer diseases and other oxidative-stress-related diseases is one of the cornerstones of modern medicine. Therefore, we tried to establish a combination of medicinal mushrooms and nanotechnology possibly with the field of medicine for the development of antibacterial agents against these MDR strains. The aim of the research was to understand the molecular identification, characterization and antibacterial action of Calvatia gigantea and Mycena leaiana. The identification of fruiting body species via morpho-anatomical and molecular methods was necessary to analyze the genetic variability and phylogenetic relationships of mushrooms. Phylogenetic analysis revealed that Calvatia from Hunza, Pakistan, exhibited 98% resemblance to the previously discovered Langermannia gigantean (DQ112623) and L. gigantean (LN714562) from northern Europe, and Mycena (Pakistan) showed a 97% similarity to M. leaiana (MF686520) and M. leaiana (MW448623) from the USA. UV-vis, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD) were used for AgNPs’ characterization. The UV-vis absorption peak of 500–600 nm indicates the AgNPs’ presence. XRD results determined Calvatia gigantea AgNPs were nanocrystals and Mycena leaiana seems to be amorphous. In addition, SEM results showed the cubic morphology of C. gigantea with a diameter of 65 nm, and the FTIR spectra of fruiting body revealed the presence of functional groups—carboxyl, nitro, and hydroxyl—in AgNPs, which catalyzed the reduction of Ag+ to Ag0. Further antibacterial activity of mushrooms against MDR strains was determined via agar well diffusion assay, and Minimum Inhibitory Concentration (MIC) was estimated by qualitative experimentation using the broth dilution method. All experiments were conducted in triplicate. The results showed that the mushroom AgNPs, along with their synergy and nano-composites (with the exception of Ethyl-acetate), were shown to have zones of inhibition from 4 mm to 29 mm against multidrug-resistant pathogens such as Acinetobacter baumannii, Staphylococcus aureus, Pseudomonas aeruginosa, Klebsiella pneumonia, Proteus mirabilis, Enterobacter cloacae and Escherichia coli. The mushroom composites were active against most of the tested microorganisms whilst the lowest MIC value (10–40 mg/mL) was recorded against MDR strains. Hence, the present study suggested the possibility of employing compounds present in mushrooms for the development of new antibacterial agents, as well as efflux pump inhibitors.

Klebsiella pneumoniae is a common cause of multidrug-resistant (MDR) pneumonia, bacteremia, urinary tract infections (UTIs), and other systemic infections. K. pneumoniae is the third most common pathogen in blood cultures from sepsis patients. It can cause severe epidemic and endemic nosocomial infections. Antibiotic treatment of K. pneumoniae infections is getting increasingly challenging due to the development of antimicrobial resistance among pathogens. Hence, a new alternative strategy is required to treat such infections. Bacteriophages are the most prevalent biological entity on the planet with an estimated 10³¹ particles. As obligatory intracellular parasites, they infect bacterial cells. They have a high host specificity and can replicate and lyse bacterial cells. In this research, two novel indigenous bacteriophages against K. pneumoniae strain kp8890 were isolated, characterized, and labeled as ZI3 and HI3. Both these phages were found to have a specific host range for K. pneumoniae. HI3 was able to lyse 7 out of 10 different K. pneumoniae clinical isolates, while ZI3 was able to lyse 5 out of 10 isolates, although it could not infect bacteria from other species. The isolated phages showed viability up to 50°C and pH ranging from 3 to 9. HI3 inhibited bacterial growth for 18 hours. Whereas, ZI3 showed an excellent bacterial reduction ability by inhibiting and decreasing the number of initial bacterial inoculum for 24 hours of observation. Keeping in view the excellent bacterial growth reduction, phage titer, pH and thermal stability, and host range, it is suggested that both bacteriophages, that is, ZI3 and HI3 can be potential phage therapy candidates after necessary animal modeling and clinical trials in the future.

Lipases are an extremely significant group in the biotechnologically related enzymes. Lipases have massive applications in various industries that include detergent, dairy, food, and pharmaceutical industries. Lipase producing bacteria were isolated from different oil contaminated sites using tributyrin agar as the media. All the isolates belonged to the genera Staphylococci. The isolates with highest lipolytic activity were selected by using titrimetric assay. The lipolytic activity of 2S, 10S and 12S was more noticeable than other isolates. The effects of different parameters like temperature, pH and incubation time on lipolytic activity were assessed. The isolates showed maximum activity at 30°C 2S and 12S displayed least activity at 45°C and 10S displayed least activity at the lowest provided temperature that was 25°C. Incubation time of 20-30 minutes was effective in increasing the enzyme activity considerably. 25 minutes was shown to decrease the lipolytic potential of 10S and 45 minutes of isolate 2S and 12S. Thin layer chromatography was also employed for the visualization of fatty acids bands. The isolates were identified as Staphylococcus species through 16S rRNA gene sequencing. Such isolates can be of industrial importance due to their ability to produce industrially important enzymes.

“Iqbal Ahmad Alvi” and “Muhammad Ikram” were not included as authors in the original publication