Skin color disorders can be caused by various factors, such as excessive exposure to sunlight, aging and hormonal imbalance during pregnancy, or taking some medications. Kojic acid (KA) is a natural metabolite produced by fungi that has the ability to inhibit tyrosinase activity in synthesis of melanin. The major applications of KA and its derivatives in medicine are based on their biocompatibility, antimicrobial and antiviral, antitumor, antidiabetic, anticancer, anti-speck, anti-parasitic, and pesticidal and insecticidal properties. In addition, KA and its derivatives are used as anti-oxidant, anti-proliferative, anti-inflammatory, radio protective and skin-lightening agent in skin creams, lotions, soaps, and dental care products. KA has the ability to act as a UV protector, suppressor of hyperpigmentation in human and restrainer of melanin formation, due to its tyrosinase inhibitory activity. Also, KA could be developed as a chemo sensitizer to enhance efficacy of commercial antifungal drugs or fungicides. In general, KA and its derivatives have wide applications in cosmetics and pharmaceutical industries.

In recent years, the researchers and drug designers have given growing attention to new nanotechnology strategies to improve drug delivery to the central nervous system (CNS). Nanotechnology has a great potential to affect the treatment of neurological disorders, mainly Alzheimer's disease, Parkinson's disease, brain tumors, and stroke. With regard to neurodegeneration, several studies showed that nanomaterials have been successfully used for the treatments of CNS disorders. In this regard, nanocarriers have facilitated the targeted delivery of chemotherapeutics resulting in the efficient inhibition of disease progression in malignant brain tumors. Therefore, the most efficacious application of nanomaterials is the use of these substances in the treatment of CNS disease that enhances the overall effect of drug and highlights the importance of nano-therapeutics. This study was conducted to review the evidence on the applications of nanotechnology in designing drug delivery systems with the ability to cross through the blood-brain barrier (BBB) in order to transfer the therapeutic agents to the CNS.

Due to the vast and inappropriate use of the antibiotics, microorganisms have begun to develop resistance to the commonly used antimicrobial agents. So therefore, development of the new and effective antimicrobial agents seems to be necessary. According to some recent reports, carbon-based nanomaterials such as fullerenes, carbon nanotubes (CNTs) (especially single-walled carbon nanotubes (SWCNTs)) and graphene oxide (GO) nanoparticles show potent antimicrobial properties. In present review, we have briefly summarized the antimicrobial activity of carbon-based nanoparticles together with their mechanism of action. Reviewed literature show that the size of carbon nanoparticles plays an important role in the inactivation of the microorganisms. As major mechanism, direct contact of microorganisms with carbon nanostructures seriously affects their cellular membrane integrity, metabolic processes and morphology. The antimicrobial activity of carbon-based nanostructures may interestingly be investigated in the near future owing to their high surface/volume ratio, large inner volume and other unique chemical and physical properties. In addition, application of functionalized carbon nanomaterials as carriers for the ordinary antibiotics possibly will decrease the associated resistance, enhance their bioavailability and provide their targeted delivery.

The diverse pleiotropic pharmacological effects of curcumin nanoformulations have turned it into an attractive natural compound in different health-related problems. A great body of evidence has shown the impact of curcumin and its nanoformulations on the differentiation of stem cells. The current review highlights cellular and molecular mechanisms connected with the osteogenic differentiation of mesenchymal stem cells (MSCs) in the scaffolds benefiting from the presence of nanocurcumin pointing toward the role of inhibitory or stimulant signal transduction pathways in detail. Moreover, the effects of different concentrations as well as the structural modifications of curcumin on the differentiation of MSCs have been addressed.