Curcumin exerts a wide range of beneficial physiological and pharmacological activities, including antioxidant, anti-amyloid, anti-inflammatory, anti-microbial, anti-neoplastic, immune-modulating, metabolism regulating, anti-depressant, neuroprotective and tissue protective effects. However, its poor solubility and poor absorption in the free form in the gastrointestinal tract and its rapid biotransformation to inactive metabolites greatly limit its utility as a health-promoting agent and dietary supplement. Recent advances in micro- and nano-formulations of curcumin with greatly enhanced absorption resulting in desirable blood levels of the active forms of curcumin now make it possible to address a wide range of potential applications, including pain management, and as tissue protective. Using these forms of highly bioavailable curcumin now enable a broad spectrum of appropriate studies to be conducted. This review discusses the formulations designed to enhance bioavailability, metabolism of curcumin, relationships between solubility and particle size relative to bioavailability, human pharmacokinetic studies involving formulated curcumin products, the widely used but inappropriate practice of hydrolyzing plasma samples for quantification of blood curcumin, current applications of curcumin and its metabolites and promising directions for health maintenance and applications.

Objectives: Dysfunctional metabolism of carbohydrates is a fundamental component of many dietary-related disorders. It has been hypothesized that plant extracts containing high levels of antioxidants may have the ability to stabilize carbohydrate regulation. The aim of this study was to assess the effects of a polyphenol-rich sugarcane extract on cellular pathways related to carbohydrate metabolism. Methods: We evaluated the antioxidant activity of a polyphenol-rich sugarcane extract obtained by a patented hydrophobic extract process and its therapeutic potential to regulate carbohydrate metabolism and protect against metabolic disorders such as type 2 diabetes. Results: Quantitative analytical studies support that the polyphenol-rich sugarcane extract has a high concentration of polyphenols and antioxidant compounds. The follow-up cellular studies via Caco-2 cells and dysfunctional β-cell models suggested that the polyphenol-rich sugarcane extract may help deter glucose and fructose uptake in intestinal cells and restore insulin production in dysfunctional β-cells—key functions in managing diabetic conditions. Conclusions: These findings suggest that sugarcane polyphenols may modulate cellular mechanism in a manner that is beneficial to health.