Logy, University of Zagreb, Pierottijeva 6, ten 000 Zagreb, Croatia; [email protected] (E.D.); [email protected] (Z.Z.); [email protected]

Logy, University of Zagreb, Pierottijeva 6, ten 000 Zagreb, Croatia; [email protected] (E.D.); [email protected] (Z.Z.); [email protected] (S.P.); [email protected] (V.D.-U.) Correspondence: [email protected]: Dobroslavi, E.; Elez c Garofuli, I.; Zori, Z.; Pedisi, S.; c c c Dragovi-Uzelac, V. Polyphenolic c Characterization and Antioxidant Capacity of Laurus Benzyldimethylstearylammonium site nobilis L. Leaf Extracts Obtained by Green and Conventional extraction Tactics. Processes 2021, 9, 1840. https:// doi.org/10.3390/pr9101840 Academic Editor: Elwira Sieniawska Received: 24 September 2021 Accepted: 14 October 2021 Published: 16 OctoberAbstract: Laurus nobilis L. is definitely an evergreen Mediterranean shrub whose Ganciclovir-d5 Purity leaves happen to be known for various health-promoting effects primarily attributed to polyphenols. Microwave- (MAE) and ultrasound-assisted extraction (UAE) are green extraction procedures that allow productive isolation of polyphenols from plant material. Hence, the aim of this analysis was to optimize the extraction circumstances of MAE (ethanol percentage, temperature, extraction time, microwave energy) and UAE (ethanol percentage, extraction time, amplitude) of polyphenols from Laurus nobilis L. leaves and to assess their polyphenolic profile by ultra performance liquid chromatography- tandem mass spectrometry (UPLC-MS/MS) and antioxidant capacity by oxygen radical absorbance capacity (ORAC) assay. Optimal MAE circumstances had been 50 ethanol, 80 C, ten min and 400 W. Optimal UAE situations have been 70 ethanol, ten min and 50 amplitude. Spectrophotometric analysis showed the highest total phenolic content within the extracts was obtained by MAE, compared to traditional heat-reflux extraction (CRE) and UAE. The polyphenolic profile of all obtained extracts incorporated 29 compounds, with kaempferol and quercetin glycosides being one of the most abundant. UPLC-MS/MS showed the highest total phenolic content material in the extracts obtained by CRE. ORAC assay showed the highest antioxidant capacity in extracts obtained by CRE, which is in agreement with all the polyphenolic profile determined by UPLC-MS/MS. Keyword phrases: Laurus nobilis L.; plant extracts; polyphenols; microwave-assisted extraction; ultrasoundassisted extraction; UPLC-MS/MS; ORAC1. Introduction Laurus nobilis L., a representative on the family members Lauraceae, is definitely an evergreen shrub native towards the Mediterranean area. The leaves of this plant have traditionally been made use of in folk medicine to treat a variety of overall health circumstances, primarily respiratory and gastrointestinal disorders [1]. On account of their effective effects, which presently can be attributed to various biological activities of leaf extracts and crucial oils like antioxidant [2,3], antiinflammatory [4,5], antimicrobial and antifungal [6,7], the chemical composition of Laurus nobilis L. leaves has been studied to a greater extent than that of other plant parts. Laurus nobilis L. leaves comprise the aforementioned essential oils, alkaloids, norisoprenoids, sugars, polysaccharides, organic acids, tocopherols as well as a wide array of polyphenols like distinct flavonoids, phenolic acids, tannins and lignans [8]. Polyphenols are a group of compounds that are of specific interest resulting from their redox properties, as they could act as antioxidant agents [9] and, therefore, are largely responsible for the antioxidant activity of Laurus nobilis L. [3,ten,11]. Plant material generally consists of a wide selection of polyphenols, such as very simple to highly polymerized compounds which can also be conjoined with vario.