Cancer is one of the most common health problems responsible for outnumbered deaths worldwide. Nanomedicine plays an important role in developing alternative and more effective treatment strategies for cancer theranostics. However, the toxicity, high cost and nanoparticles (NPs) production complexity are some of the major issues that obstruct the use of existing nanomedicine. Recently, the green synthesis of biogenic NPs from plants and microbial sources has become an emerging field due to their safer, eco-friendly, simple, fast, energy efficient, low-cost and less toxic nature. Interestingly, NPs play a key role in diagnosis of tumor at the initial stage by allowing cellular visualization. Furthermore, prospective applications of green NPs include magnetically responsive drug delivery, anti-cancer activity, photo-thermal therapy and bio-imaging. The present review provides perspective on the use of anti-cancer green bionanomaterials with a focus on their present status and future prospects in the theranostics of cancer. GRAPHICAL ABSTRACT

Silver nanoparticles (AgNPs) have been undeniable for its antimicrobial activity while its antitumour potential is still limited. Therefore, the present study focused on determining cytotoxic effects of AgNPs on Michigan cancer foundation‐7 (MCF‐7) breast cancer cells and its corresponding mechanism of cell death. Herein, the authors developed a bio‐reduction method for AgNPs synthesis using actinomycetes isolated from marine soil sample. The isolated strain was identified by 16s ribotyping method and it was found to be Streptomyces atrovirens . Furthermore, the synthesised AgNPs were characterised by various bio‐analytical techniques such as ultraviolet–visible spectrophotometer, atomic force microscopy, transmission electron microscopy, Fourier transform infra‐red spectroscopy, and X‐ray diffraction. Moreover, the results of 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide assay reveals 44.51 µg of AgNPs to have profound inhibition of cancer cell growth; furthermore, the inhibition of MCF‐7 breast cancer cell line was found to be dose dependent on treatment with AgNPs. Acridine orange and ethidium bromide double staining methods were performed for cell morphological analysis. The present results showed that biosynthesised AgNPs might be emerging alternative biomaterials for human breast cancer therapy.

The emergence of multi‐drug‐resistant microorganisms in hospital environments is a global public health problem and threat to everyone, especially HIV‐infected patients. Methicillin‐resistant Staphylococcus aureus (MRSA) and coagulase‐negative Staphylococci (CoNS) are the major causative agents associated with morbidity and mortality in HIV patients. Therefore, control of MRSA and CoNS‐related infections in HIV patients is a worldwide concern. To investigate novel, potent, and cost‐effective therapeutic approaches, the current study reports a simple and rapid synthesis of silver nanoparticles (AgNPs) using aqueous leaf extract of Alysicarpus monilifer and its antibacterial efficacy against multi‐drug‐resistant MRSA and CoNS isolates from HIV patients. The green‐synthesized AgNPs were characterized using ultraviolet‐visible spectroscopy, transmission electron microscopy, energy dispersive X‐ray analysis, selected area electron diffraction pattern, X‐ray diffraction patterns, and Fourier transform infrared spectroscopy. Stable, well‐defined AgNPs, mostly spherical in shape with mean size of 15 ± 2 nm, were obtained within an hour. Moreover, green synthesized AgNPs revealed significant dose‐dependent antibacterial action against MRSA and CoNS isolates. This study concludes that biogenic AgNPs have demonstrated to be potent antibacterial agents in comparison with conventional antibiotics.