Determination of Quercetin and Rutin in Selected Herbs and Pharmaceutical Preparations

Quercetin: A Potential Polydynamic Drug

The study of natural products as potential drug leads has gained tremendous research interest. Quercetin is one of those natural products. It belongs to the family of flavonoids and, more specifically, flavonols. This review summarizes the beneficial pharmaceutical effects of quercetin, such as its anti-cancer, anti-inflammatory, and antimicrobial properties, which are some of the quercetin effects described in this review. Nevertheless, quercetin shows poor bioavailability and low solubility. For this reason, its encapsulation in macromolecules increases its bioavailability and therefore pharmaceutical efficiency. In this review, a brief description of the different forms of encapsulation of quercetin are described, and new ones are proposed. The beneficial effects of applying new pharmaceutical forms of nanotechnology are outlined.

Analytical Methods for the Determination of Quercetin and Quercetin Glycosides in Pharmaceuticals and Biological Samples

Flavonoids are plant-derived compounds that have several health benefits, including antioxidative, anti-inflammatory, anti-mutagenic, and anti-carcinogenic effects. Quercetin is a flavonoid that is widely present in various fruits, vegetables, and drinks. Accurate determination of quercetin in different samples is of great importance for its potential health benefits. This review, is an overview of sample preparation and determination methods for quercetin in diverse matrices. Previous research on sample preparation and determination methods for quercetin are summarized, highlighting the advantages and disadvantages of each method and providing insights into recent developments in quercetin sample treatment. Various analytical techniques are discussed including spectroscopic, chromatographic, electrophoretic, and electrochemical methods for the determination of quercetin and its derivatives in different samples. UV-Vis (Ultraviolet-visible) spectrophotometry is simple and inexpensive but lacks selectivity. Chromatographic techniques (HPLC, GC) offer selectivity and sensitivity, while electrophoretic and electrochemical methods provide high resolution and low detection limits, respectively. The aim of this review is to comprehensively explore the determination methods for quercetin and quercetin glycosides in diverse matrices, with emphasis on pharmaceutical and biological samples. The review also provides a theoretical basis for method development and application for the analysis of quercetin and quercetin glycosides in real samples.

Quality control and standardization of Quercetin in herbal medicines by spectroscopic and chromatographic techniques

Background

Herbal medicines and their preparations have been mostly used since from thousands of years in all developing and developed countries in the primary health care of society and community. Flavonoids are the class of polyphenolic compounds, which are mainly distributed throughout the plant kingdom. Quercetin is a flavonoid which shows major pharmacological activities and effectively used for the management and treatment of various diseases and disorders. Many herbal medicines and their formulations containing Quercetin are available in market and hence quality control of Quercetin in is very important and essential in manufacturing industries

Main body of the abstract

We have reviewed various scientific research published on quality control analysis and standardization of Quercetin in its isolated form, extract or any other herbal or polyherbal preparation. We have mainly focused on the spectroscopic and chromatographic methods for qualitative and quantitative analysis of Quercetin and they were comprehensively presented in the present review work.

Short conclusion

The present review concludes that the spectroscopic and chromatographic methods play great role in the quality control and standardization of Quercetin in its isolated form, extract and in its herbal and polyherbal preparation.

Simultaneous Determination of Rutin, Luteolin, Quercetin, and Betulinic Acid in the Extract of Disporopsis pernyi (Hua) Diels by UPLC

Disporopsis pernyi (Hua) Diels, which belongs to genus Disporopsis, has been widely used for the treatment of abnormal sweating, chronic cough, and so forth. An ultra-performance liquid chromatography (UPLC) analysis was developed for the determination of rutin, luteolin, quercetin, and betulinic acid in Disporopsis pernyi (Hua) Diels roots. UPLC analysis was conducted by using a Shim-pack XR-ODS column with gradient elution with the mobile phase of acetonitrile and water containing 0.1% formic acid and with a flow rate of 0.2 mL/min, detected at 210, 254, and 280 nm. The method was precise, with relative standard deviation < 2.0%. The recoveries for the four components in Disporopsis pernyi (Hua) Diels were between 98.5 and 100.9%. The average contents of rutin, luteolin, quercetin, and betulinic acid in roots were 5.63, 2.51, 3.87, and 2.41 μg/g, respectively. The method was accurate and reproducible and it can provide a quantitative basis for quality control of Disporopsis pernyi (Hua) Diels.