Catechins as Model Bioactive Compounds for Biomedical Applications.

Research regarding polyphenols has gained prominence over the years because of their potential as pharmacological nutrients. Most polyphenols are flavanols, commonly known as catechins, which are present in high amounts in green tea. Catechins are promising candidates in the field of biomedicine. The health benefits of catechins, notably their antioxidant effects, are related to their chemical structure and the total number of hydroxyl groups. In addition, catechins possess strong activities against several pathogens, including bacteria, viruses, parasites, and fungi. One major limitation of these compounds is low bioavailability. Catechins are poorly absorbed by intestinal barriers. Some protective mechanisms may be required to maintain or even increase the stability and bioavailability of these molecules within living organisms. Moreover, novel delivery systems, such as scaffolds, fibers, sponges, and capsules, have been proposed. This review focuses on the unique structures and bioactive properties of catechins and their role in inflammatory responses as well as provides a perspective on their use in future human health applications.

Plant Extracts Loaded in Nanostructured Drug Delivery Systems for Treating Parasitic and Antimicrobial Diseases.

BACKGROUND: Plant extracts loaded in nanostructured drug delivery systems (NDDSs) have been reported as an alternative to current therapies for treating parasitic and antimicrobial diseases. Among their advantages, plant extracts in NDSSs increase the stability of the drugs against environmental factors by promoting protection against oxygen, humidity, and light, among other factors; improve the solubility of hydrophobic compounds; enhance the low absorption of the active components of the extracts (i.e., biopharmaceutical classification II), which results in greater bioavailability; and control the release rate of the substances, which is fundamental to improving the therapeutic effectiveness. In this review, we present the most recent data on NDDSs using plant extracts and report results obtained from studies related to in vitro and in vivo biological activities.