Background Rutin is a common dietary flavonoid which has received great attention in literature, due to their pharmacological properties, including antimicrobial, anti-inflammatory, anticancer, antidiabetic, inter alia . Over 860 products containing rutin are currently marketed in the US. The major disadvantage associated with rutin is its constrained bioavailability, mainly caused by its low aqueous solubility, poor stability and limited membrane permeability. Scope and approach The aim of this contribution is to give an overview of the current methods (conventional and innovative) for the extraction, identification and purification of rutin. Furthermore, recent findings regarding its pharmacological activities and the different approaches to increase rutin solubility in both aqueous and lipid phases will be discussed. Key findings and conclusions Current trends on extraction process have been focused on the discovery and design of green and sustainable extraction techniques to optimize the recovery of rutin. Despite the bioactivity expressed in different in vitro systems, its biological effects in vivo are limited by the poor bioavailability of the flavonoid. The utilization of delivery systems for rutin or its enzymatic or chemical transformation towards highly soluble derivatives have the potential to improve rutin bioavailability, as well as its stability and/or specific biological properties. These novel rutin formulations may bring this promising flavonoid to the forefront of nutraceuticals for the prevention and/or treatment of various chronic human diseases.

Rutin: A review on extraction, identification and purification methods, biological activities and approaches to enhance its bioavailability

“Let food be thy medicine and medicine be thy food” was expressed by Hippocrates more than 2000 years ago and the health benefits of natural food products have been considered for different goals s...

https://www.tandfonline.com/doi/pdf/10.1080/10942912.2017.1354017

Polyphenols and their benefits: A review

An overview of natural antimicrobials role in food.

Oxidative stress mitigation by antioxidants - An overview on their chemistry and influences on health status.

Ultrasound assisted extraction (UAE) is widely used in recent times for its benefits, but it is difficult to find literature that comprehensively addresses the effect of UAE-specific parameters such as temperature, frequency, power, solvent type, and solvent to material ratio on extracted compounds and their functionality. There is no review done so far on the effects of all UAE parameters on polyphenol extracts to guide the design of extraction protocols. This review therefore focuses on the effects of UAE parameters on the yield and composition, as well as the effects of the UAE on the antioxidant, anticancer, and antimicrobial properties of phenolic extracts. Higher extraction temperatures above 50 °C are degradative to polyphenols in extracts; lower frequencies within the power ultrasound range below 40 kHz are most effective; polyphenol yield generally increases with increasing power, but with a threshold, beyond which no significant increase is observed; and higher ultrasound power produces free hydroxyl radicals which degrade polyphenols, especially in the presence of high water content. A comparative assessment of literature showed that, UAE does not only contribute to increased extraction yield of polyphenols, but also better preserves and increases the biological activity of polyphenol extracts compared to traditional maceration and Soxhlet extraction. A full picture of UAE is given to serve as a reference material on the control of UAE parameters for desired results and efficiency.

The effects of ultrasound assisted extraction on yield, antioxidant, anticancer and antimicrobial activity of polyphenol extracts: A review

Being secondary plant metabolites, polyphenols represent a large and diverse group of substances abundantly present in a majority of fruits, herbs and vegetables. The current contribution is focused on their bioavailability, antioxidative and anticarcinogenic properties. An overview of extraction methods is also given, with supercritical fluid extraction highlighted as a promising eco-friendly alternative providing exceptional separation and protection from degradation of unstable polyphenols. The protective role of polyphenols against reactive oxygen and nitrogen species, UV light, plant pathogens, parasites and predators results in several beneficial biological activities giving rise to prophylaxis or possibly even to a cure for several prevailing human diseases, especially various cancer types. Omnipresence, specificity of the response and the absence of or low toxicity are crucial advantages of polyphenols as anticancer agents. The main problem represents their low bioavailability and rapid metabolism. One of the promising solutions lies in nanoformulation of polyphenols that prevents their degradation and thus enables significantly higher concentrations to reach the target cells. Another, more practiced, solution is the use of mixtures of various polyphenols that bring synergistic effects, resulting in lowering of the required therapeutic dose and in multitargeted action. The combination of polyphenols with existing drugs and therapies also shows promising results and significantly reduces their toxicity.

https://www.mdpi.com/1420-3049/21/7/901/pdf

Eva Brglez Mojzer

Papers

Polyphenols: Extraction Methods, Antioxidative Action, Bioavailability and Anticarcinogenic Effects