Biogenic synthesis of silver (AgNPs) and gold nanoparticles (AuNPs) using aqueous extract of Euphrasia officinalis has been reported. Stable AgNPs and AuNPs were formed on adding aqueous solutions of silver nitrate and chloroauric acid with E. officinalis leaf extract, in 19 min and 2 min, respectively. The synthesis method used in present study was simple, reliable, rapid, cost effective and ecofriendly. The synthesized nanoparticles were characterized with field emission transmission electron microscopy (FE-TEM), elemental mapping, selected area diffraction pattern (SAED), energy-dispersive X-ray spectroscopy (EDS), X-ray diffractometer (XRD), particle size distribution, zeta potential and Fourier-transform infrared spectroscopy (FTIR). The UV-Vis spectrum confirmed the synthesis of nanoparticles as the absorption band was observed at 450 nm for AgNPs and at 558 nm for AuNPs. The TEM images revealed quasi-spherical shape of AgNPs and AuNPs. The size of nanoparticles was determined to be 40.37 ± 1.8 nm for AgNPs and 49.72 ± 1.2 nm for AuNPs. The zeta potential value demonstrated the negative surface charge and stable nature of nanoparticles. Crystalline nature of the nanoparticles in the face-centred cubic (fcc) structure was confirmed by the peaks in the XRD pattern and SAED pattern. FTIR results showed the functional groups involved in reduction of silver and gold ions to metal nanoparticles. For biomedical application, the nanoparticles have been explored for anticancer, antibacterial and biofilm inhibition activities. It was observed that AgNPs exert anticancer activity against human lung cancer (A549) and human cervical cancer (HeLa) cell lines. On the other hand, AuNPs were able to inhibit only human cervical cancer cells. Furthermore, the AgNPs were active against clinically isolated human pathogens like Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus and Vibrio parahaemolyticus. Additionally, AgNPs also showed biofilm inhibition activity against S. aureus and P. aeruginosa.

Silver nanoparticles (AgNPs) are known to have bacteriostatic and bactericidal effects. The present study highlights the extracellular synthesis of AgNPs and its antibacterial properties. The AgNPs were synthesized using Pseudomonas sp. THG-LS1.4 strain which had been isolated from soil. The AgNPs were characterized by field emission-transmission electron microscopy (FE-TEM), X-ray diffraction (XRD), Fourier transform-infrared (FT-IR) spectroscopy, and particle size distribution (DLS). The AgNPs displayed maximum absorbance at 412 nm and were irregular in shape ranging from 10 to 40 nm. The XRD spectroscopy results demonstrated the crystalline nature of nanoparticles. The AgNPs showed antimicrobial activity against Bacillus cereus, Staphylococcus aureus, Candida tropicalis, Vibrio parahaemolyticus, Escherichia coli and Pseudomonas aeruginosa. Furthermore, the AgNPs were also evaluated for their increased antibacterial activities with various antibiotics against Escherichia coli, Pseudomonas aeruginosa and Salmonella enterica. Additionally, AgNPs showd biofilm inhibition activity. The biosynthesized AgNPs were found to be a potent agent against tested pathogens. More importantly, we highlight the applications of AgNPs as an antimicrobial agent.

Human adipose-derived mesenchymal stem cells-conditioned medium (ADSC-CM) contains cytokines and growth factors that can facilitate the regeneration and repair of various tissues and organs. In the present study, the protective activity of ADSC-CM treatment was investigated in UVB-irradiated human keratinocyte cell line HaCaTs and normal human dermal fibroblasts (NHDFs). It was found that ADSC-CM can modulate the expression of the signaling molecules in the early UVB responsive signaling pathways, including mitogen activated protein kinases (MAPKs), activator protein 1 (AP-1), and nuclear factor kappa B (NF-κB). In addition, ADSC-CM treatment could upregulate antioxidant response element (ARE) such as phase II gene heme oxygenase-1 (HO-1) and increase the expression of collagen synthesis enhancer gene transforming growth factor-β (TGF-β). The expression of matrix metalloproteinase-1 (MMP-1) and procollagen type I synthesis inhibitors such as interleukin-6 (IL-6) was also found to be suppressed upon ADSC-CM treatment. Taken together, our study illustrates the anti-photoaging activities of ADSC-CM in cell-based models.