Title : Optimization of polyphenol extraction in aerial parts of Agrimonia eupatoria l. And Cichorium intybus L
Abstract:
Phenolic compounds are essential for human health and exhibit a wide range of pharmacological activities, such as antioxidant, anti-inflammatory, antimicrobial, antitumor properties, whereby they can be used in the pharmaceutical, cosmetic and food industry with the development of new products. The aerial parts of Agrimonia eupatoria and Cichorium intybus were collected in flowering time, on June 2024, from the collection of Scientific Practical Center of Medicinal Plants (SPCMP) of Nicolae Testemitanu State University of Medicine and Pharmacy, Chisinau, Republic of Moldova. Extraction of phenolic compounds from plant products was performed by different extraction conditions, using the water bath with the condenser reflux, the magnetic stirrer with heating and the ultrasound assisted bath, respecting the ratio of plant product to ethyl alcohol 60% (1:20) and extraction time of 30 minutes for all methods applied. Total phenolic content (TPC) was determined using Folin-Ciocalteu reagent with absorbance reading at wavelength λ=760 nm, total flavonoid content (TFC) with 2.5% AlCl3 at wavelength λ=430 nm; total phenolic acids (TPA) were determined using Arnow reagent (5% NaNO2 and Na2MoO4) and 2 M NaOH at wavelength λ=500 nm, with the Metertech UV/VIS SP 8001 spectrophotometer in the Department of Pharmacognosy and Pharmaceutical Botany. Phenolic compounds were higher in ethyl extracts obtained with the magnetic stirrer: the TPC reported as gallic acid equivalent (mg GA/g) for A. eupatoria–78.42±0.025, C. intybus –30.65±0.013; TFC equivalent in rutine (mg RU/g) for A. eupatoria –39.25±0.120, C. intybus – 18.35±0.041; and TPA reported as caffeic acid (mg CA/g) for A. eupatoria –3.78 ±0.049, C. intybus–10.52±0.015; followed by the content of TFA, TFC, TAC obtained at ultrasound bath. The lower content of phenolic compounds in ethyl extracts were obtained at the water bath with the condenser reflux: the TPC (mg GA/g) for A. eupatoria – 52.21±0.031, C. intybus –15.29±0.018; TFC (mg RU/g) for A. eupatoria – 21.45±0.023, C. intybus – 10.47±0.035; and TPA reported as caffeic acid (mg CA/g) for A. eupatoria – 2.15 ±0.034, C. intybus –8.43±0.016.The results indicate that species from the SPCMP collection: A. eupatoria and C. intybus are rich in polyphenolic compounds and represent a great potential for the pharmaceutical industry. Extraction methods influence the content of phenolic compounds in plant products, and magnetic stirrer extraction with heating is optimal for Agrimoniae herba and Cichorii herba. Ultrasonic assisted bath and water bath with the condenser reflux, can also serve as alternative methods for the extraction of polyphenolic compounds from plant products with insignificant deviations. The research was carried out within the project No. PN-IV-P8-8.3-ROMD- 2023-0022.