The Effect of Traditional and Cyclodextrin-Assisted Extraction Methods on Trifolium pratense L. (Red Clover) Extracts Antioxidant Potential

Abstract

Red clover is the subject of numerous studies because of its antioxidant properties, the positive influence of isoflavones on the health, and its potential use in the prevention and treatment of chronic diseases. The right excipients, such as cyclodextrins, can increase the profile of valuable phenolic compounds in extraction media to obtain rich in antioxidants, extracts that can be used in nutraceuticals production. The aim of this study was to investigate and compare the total phenolic content, flavonoid content, and antioxidant activity of red clover aerial parts, aqueous and ethanolic extracts prepared using traditional and cyclodextrins-assisted methods. The antioxidant activity of the extracts was established using ABTS, DPPH, FRAP, and ABTS-post column methods. It was determined that cyclodextrins significantly increased total phenolic content (compared with control)—using β-cyclodextrin 20.29% (in aqueous samples); γ-cyclodextrin 22.26% (in ethanolic samples). All the samples prepared with excipients demonstrated a strong relationship between total phenolic content and DPPH assay. Study showed that for extraction with water, the highest amounts of phenolic compounds, flavonoids and antioxidant activity will be achieved with β-cyclodextrin, but extractions with ethanol will give the best results with γ-cyclodextrin. Therefore, cyclodextrins are a great and safe tool for obtaining rich, red clover flower extracts that are high in antioxidant activity, which can be used in the pharmaceutical industry for nutraceuticals production.

Phenological Variations in the Content of Polyphenols and Triterpenoids in Epilobium angustifolium Herb Originating from Ukraine

“…Plant phenolic compounds (e.g., flavonoids, phenolic acids) possess antioxidant properties, which means that they can neutralize harmful free radicals in the body that can cause oxidative damage to cells [ 26 ] and prevent to the development of chronic diseases, such as cancer, diabetes [ 27 ], and cardiovascular disease [ 28 ].…”

Technological Functionalisation of Microencapsulated Genistein and Daidzein Delivery Systems Soluble in the Stomach and Intestines

“…The total phenolic content was determined as in our previous research [ 31 ]. Folin–Ciocalteu’s phenol reagent (1:9 dilution in distilled water) was used.…”

Application of Antiviral, Antioxidant and Antibacterial Glycyrrhiza glabra L., Trifolium pratense L. Extracts and Myristica fragrans Houtt. Essential Oil in Microcapsules

“…Grinding was performed at 4025 g (6000 rpm) using a 0.5 mm trapezoid hole sieve. The extraction was performed as in the previous study using excipient β-cyclodextrin (β-CD) [ 36 ].…”

“…High-performance liquid chromatography with diode array detectors (HPLC-PDA) was performed as described in previous work by Kazlauskaite et al [ 36 ]. It was carried out using the Shimadzu Nexera X2 LC-30AD HPLC system (Shimadzu, Tokyo, Japan), equipped with an SPD-M20A diode array detector (DAD).…”

“…Total phenolic and flavonoid content and antioxidant activity methods ABTS, DPPH, and FRAP were carried out as described in Kazlauskaite et al [ 36 ].…”