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The propolis produced by bees is used by them to protect their hives. The cavity inside the hive’s walls is filled in during cold days to reduce entry points and mummify any intruders to ensure their survival. A current focus in nanotechnology and nanoscience is the green biosynthesis of nanoparticles (NPs) using biomaterials. Research on green methods for making metal oxide NPs is gaining momentum to safeguard the environment from the potential dangers associated with toxic chemicals. This study aimed to synthesize copper NPs (CuNPs) via propolis extraction, a novel application of nanoscience. The study was conducted under a range of pH, time conditions, and concentration ratios, and its properties were characterized by UV-Vis absorption spectra, XRD, and FTIR. An FTIR analysis revealed that compounds found in propolis extract could have an effect on the surface modification of the synthesized NPs. The propolis (Khalkhal) extract spectrum exhibited a sharp peak at 3422 cm−1, caused by free hydroxyl groups and their intra/intermolecular hydrogen bonds. There were sharp peaks at 2925, 1637, and 1515 to 1076 cm−1 associated with the C = O and C = C aromatic stretching frequencies. According to UV-Vis spectrophotometry investigation, CuO NPs exhibit a characteristic peak at 385 nm, showing significant surface plasmon resonance (SPR) with propolis (Khalkhal) extract. Furthermore, specific wavelengths of CuO NPs demonstrate peaks at 243, 292, and 350 nm for propolis (Gilan) extract. The green synthesis of CuNPs from Gilan and Khalkhal propolis can be an appropriate candidate for clinical applications such as drug delivery systems, drug formulation, and biomedical applications.

Background. Drug resistance is currently possible anywhere in the world. Due to the discovery of antimicrobials, medicine, and health have made tremendous advances over the past several decades. Aim. This research evaluated the antimicrobial and cytotoxicity effects of green synthesis of copper oxide nanoparticles (CuO NPs) on Lactobacillus acidophilus and human embryonic kidney 293 cells (HEK). Method and Materials. Propolis was sampled and extracted. Green synthesis of CuO NPs was synthesized and characterized using SEM, TEM, DLS, BET, and zeta potential methods. L. acidophilus (ATCC 4356) was used, and the antimicrobial tests were carried out at different concentrations (10≥ mg/ml). Moreover, the cytotoxicity was evaluated using an MTT assay on human embryonic kidney 293 cells (HEK). Results. Synthesized CuO NPs using propolis extracts from Khalkhal (sample 1) and Gillan (sample 2) showed −13.2 and −14.4 mV, respectively. The hydrodynamic sizes of well-dispersed samples 1 and 2 were 3124.9 nm and 1726.7 nm, respectively. According to BET analysis, samples 1 and 2 had 5.37 and 8.45 m2/g surface area, respectively. The surface area was decreased due to the addition of propolis extract, and the pore size was increased. CuO NPs of samples 1 and 2 were visible on SEM images with diameters ranging from 75 to 145 nm and 120 to 155 nm, respectively. Based on TEM analysis, the size of CuO particles was increased in samples 1 and 2. CuO NPs particles had narrow size distributions with evenly dispersed NPs on all sides. The cell viability of the CuO NPs of samples 1 and 2 after 24, 48, and 72 hours was greater than 50%. As a result of the MIC and MBC tests, it was determined that samples 1 and 2 had the same effect against L. acidophilus (0.0024 mg/ml). Biofilm formation and degradation of sample 1 were more efficient against L. acidophilus. Conclusion. There was no evidence of cytotoxicity in the samples. In addition, results showed that the green synthesized CuO NPs from Khalkhal propolis were effective against L. acidophilus. Thus, the green synthesized CuO NPs from Khalkhal propolis were the best candidates for clinical application.

Background: Klebsiella pneumoniae has received attention due to a wide range of diseases and antibiotic resistance.The resistance to fluoroquinolones in gram-negative bacteria is often due to chromosomal mutations in the gyr and par genes. This research aimed at investigating the pattern of fluoroquinolone resistance and its relation with a mutation in the parC gene among clinical isolates of K. pneumoniae. Materials & Methods:In this descriptive-analytical study, 95 K. pneumoniae, after biochemical and molecular diagnosis, were evaluated for resistance to different antibiotics by disk diffusion agar according to CLSI recommendations and screening for ciprofloxacin-resistant isolates. Mutation in the ciprofloxacin resistance determinant region of the parC gene of K. pneumoniae resistant to ciprofloxacin was performed by PCR amplification and then amplified fragment sequencing and finally with the standard bacterial genome sequencing available at NCBI site, became BLAST through online software, Insilico, and Clustalw2. Results:The result of the antibiogram showed implies an expansion of MDR bacteria. 3.1% of isolates were resistant to all 13 antibiotics studied and 24.2% were ciprofloxacin-resistant. The highest and lowest percentages of antibiotic resistance were determined for ampicillin and amoxicillin (98.9%) and imipenem (13.6%), respectively. Sequence analysis of the parC gene showed that of 23 isolates resistant to ciprofloxacin, 16 isolates at codon 80 (I80S), one at codon 84 (E84K) were and 3 isolates also had frame-shift mutations. Conclusion:Mutations in the parC gene can be one of the major contributors to resistance to fluoroquinolones and increased MDR bacteria and nosocomial infections.

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