Review of Natural Phytochemical-Based Self-Assembled Nanostructures for Applications in Medicine

Abstract

The role of nanomedicine in disease diagnosis and treatment is indispensable. The future of nanomedicine in the pharmaceutical field is promising owing to its specificity and potency. However, its function and ultimate efficiency in clinical applications are still unsatisfactory, which can be attributed to the toxicity of nanomaterials caused by their nondegradability and accumulation in the body. To overcome the obstacles associated with the synthesized materials, researchers have focused on natural phytochemicals with good biodegradability, biocompatibility, and self-assembly capability. The structural diversity and combinational therapeutic effects of natural phytochemicals have broadened their nanomedical applications. This Review summarizes natural phytochemical-based nanostructures, including steroids, terpenoids, alkaloids, flavonoids, quinones, and polysaccharides and highlights their enormous application potential in nanomedicines. Additionally, in this Review, we summarize recent advances in nanostructures based on natural phytochemicals and introduce representative examples for drug-delivery, imaging, and theranostic applications in nanomedicine. Finally, we discuss the challenges in the rational design, synthesis, and fabrication of natural phytochemical-based nanostructures and propose feasible solutions for problems that need to be overcome to enable clinical translation.

Bioactive Peptide Nano-assemblies with pH-Triggered Shape Transformation for Antibacterial Therapy

“…Furthermore, it is interesting to note that, over the years, one of the hydroxycinnamic acid derivatives, i.e., ferulic acid, or (2 E )-3-(4-hydroxy-3-methoxyphenyl)­prop-2-enoic acid, has been recognized as an abundant phenolic acid that commonly exists in plant cell walls . Despite its abundance and clinical benefits, the use of ferulic acid is limited due to its strong hydrophobic nature, which leads to its decreased bioavailability. , Ferulic acid has been reported to exhibit antibacterial activity against several pathogenic bacterial species, like A. baumannii , C. sakazakii , etc., via superoxide ion generation, reactive oxygen species (ROS) generation, and membrane disruption. , In one of these studies, Borges et al reported the antibacterial activity of ferulic acid against pathogenic bacteria, which led to irreversible changes in the bacterial membrane via local rupture and pore formation . Another report, by Pernin et al, demonstrated the inhibitory property of ferulic acid against L. monocytogenes in an emulsified system .…”

“…24 Despite its abundance and clinical benefits, the use of ferulic acid is limited due to its strong hydrophobic nature, which leads to its decreased bioavailability. 25,26 Ferulic acid has been reported to exhibit antibacterial activity against several pathogenic bacterial species, like A. baumannii, C. sakazakii, etc., via superoxide ion generation, reactive oxygen species (ROS) generation, and membrane disruption. 27,28 In one of these studies, Borges et al reported the antibacterial activity of ferulic acid against pathogenic bacteria, which led to irreversible changes in the bacterial membrane via local rupture and pore formation.…”

Natural Small-Molecule-Based Carrier-Free Self-Assembly Library Originated from Traditional Chinese Herbal Medicine

“…Self-assembly behavior refers to the process of an orderly arrangement of molecules in a system under the action of noncovalent bonds and finally forming a structure with a certain geometric appearance . Numerous self-assembly phenomena from small molecules have been found, , like puerarin hydrogel, , gallic acid gels, pomolic acid gels, and rhein hydrogel, , and triterpenoids can also self-assemble under suitable solvent conditions, − which exhibit different morphologies and functions, such as oleanolic acid, glycyrrhetinic acid, and ursolic acid . Our previous studies and other researchers have also found binary assemblers: berberine can self-assemble with baicalin, rhein, aristolochic acid, cinnamic acid, curcumin, and sennoside A to form nanoparticles (NPs).…”

“…In addition to the self-assembly through small-molecule interactions in the decoction, some researchers found that polysaccharide , and protein , components in the decoction could also self-assemble and showed good biological activity. Meanwhile, many chemical components in TCM have unique structures and many modification sites, which facilitate self-recognition and self-assembly . Therefore, TCM decoction can be used as a carrier-free self-assembly library of small molecules to reduce blindness, contingency, and a green strategy in supramolecular design and construction.…”

“…Meanwhile, many chemical components in TCM have unique structures and many modification sites, which facilitate self-recognition and self-assembly. 10 Therefore, TCM decoction can be used as a carrier-free self-assembly library of small molecules to reduce blindness, contingency, and a green strategy in supramolecular design and construction.…”