Biofabrication of gold nanoparticles using marine endophytic fungus – Penicillium citrinum

Nanotechnology is one of the promising fields of research and generating new avenues and applications in medicine. Recently, marine floras such as, marine endophytes are gaining the attention of many researchers due to the myriad of bioactive molecules that they possess. In addition, they find applications in many pharmaceutical and cosmetic industries. In this study, they have studied the green synthesis of gold nanoparticles (AuNPs) from Penicillium citrinum (P. citrinum) and its antioxidant activity. P. citrinum was isolated from brown algae. The identity of the fungus was established by comparing its 18S rDNA sequence. AuNPs were synthesised using P. citrinum and were characterised by UV–visible spectrophotometer (UV–vis), field emission scanning electron microscope (FESEM), X‐ray diffraction, Fourier transform infrared spectroscopy and dynamic light scattering (DLS). AuNPs were tested for free radical scavenging activity by 1,1‐diphenyl‐2‐picrylhydrazyl method. The particle sizes of AuNps were determined by FESEM and DLS. The reduction of gold metal ion was confirmed from the UV–vis spectrum. AuNPs showed significant antioxidant potential and the activity was comparable to the standard ascorbic acid. Further, in vitro and in vivo studies on these AuNPs will help in developing an alternative, cost‐effective and acceptable drug for various ailments.Inspec keywords: microorganisms, nanoparticles, gold, nanofabrication, particle size, nanobiotechnology, DNA, molecular biophysics, molecular configurations, ultraviolet spectra, visible spectra, field emission electron microscopy, scanning electron microscopy, X‐ray diffraction, Fourier transform infrared spectra, light scattering, free radical reactions, biochemistryOther keywords: biofabrication, gold nanoparticles, marine endophytic fungi, Penicillium citrinum, nanotechnology, medicine applications, marine floras, marine endophytes, bioactive molecules, pharmaceutical industries, cosmetic industries, antioxidant activity, brown algae, 18S rDNA sequence, UV‐visible spectrophotometer, field emission scanning electron microscope, FESEM, X‐ray diffraction, Fourier transform infrared spectroscopy, dynamic light scattering, free radical scavenging activity, 1,1‐diphenyl‐2‐picrylhydrazyl method, particle sizes, gold metal ion reduction, antioxidant potential, standard ascorbic acid, drug, ailments, Au