## 3 Results and Discussion  
Overall Differences between Solid Waste Hydroalcoholic Extracts (TWE and FEW) Obtained by PULAE and Distillation Wastewaters (LEACH)  
As reported in Table 2, the analyzed extracts significantly differed in their antioxidant activities (ANOVA \(F_{2,3}\) = 365.4, \(p\) < 0.001 for TEAC; \(F_{2,3}\) = 374.9, \(p\) < 0.001 for AEAC), and in their phenolic and flavonoid contents (ANOVA \(F_{2,3}\) = 1100, \(p\) < 0.001, and \(F_{2,3}\) = 177.1, \(p\) < 0.001, respectively). Solid wastes (TWE and FWE) showed very similar RSA (expressed as TEAC and AEAC), TPC (expressed as GAE) and TFC values (expressed as QE). In turn, when compared with solid wastes, distillation wastewaters showed a significantly lower antioxidant activity (more than 30 times lower, both for TEAC and AEAC) and phenolic and flavonoid concentration (ca. 52 times and 300 times, respectively). Hydrolat (HYDR), generated during the extraction process of essential oils from aromatic plants, is made up of condensation water containing water-soluble, oxygenated, and volatile components in which very small amounts of essential oils remain dispersed [17]. [PERSON] et al. [32] describing the composition of the hydrolat of _L. angusifolia_ reported the following major chemical components: linalool (26.5%), bornel (9.0%), _cis_-linalool oxide (6.6%), and _trans_-linalool oxide (5.2%). These hydrosols showed antibacterial in vitro activity [33]. However, no study has been published on the antioxidant activity of laver-der hydrolats. As reported in Table 2, HYDR was very poor in phenolic compounds (0.70 + 0.00 mg of gallic acid in 100 mL) while both the antiradical activity (RSA) and the flavonoid content (TFC) were not detectable. Recently, the application of UAE to different plant matrices has produced very interesting results. Particularly, this extraction method was proposed as an innovative alternative to conventional processes to extract antioxidants, such as phenolic compounds, from several natural matrices [22; 23; 24; 25; 26]. The main advantages of UAE are the mass transfer intensification, the vegetal cell disruption, and a higher penetration of the extraction solvent to the plant tissues. Indeed, the high-frequency ultrasonic waves through the cavitation process break the vegetal cells releasing the cell contents into the extraction medium [20]. Several articles have been published on the application of UAE to extract phenolic compounds from plants such as myrtle (_Myrtus communis_ L.) [34], pomeranate (_Punica granatum_ L.) byproducts [22; 25; 26], maqui (_Aristotelia chilensis_) [35], black chokeberry (_Aronia melanocarpa_ L.) [36], slopes (_Prunus spinosa_ L.) [37] and buds (i.e., _Ribes nigrum_, _Castanea sativa_) [23; 24]. All of these studies described ultrasound as an efficient and a more suitable method for the extraction of these degradable bioactive compounds, also in comparison to other green extractive technologies (e.g., microwave). Moreover, several comparative studies on the extraction of phenolic compounds from the flowers and buds of different species were carried out using ultrasounds, traditional maceration, and extraction assisted by heat (i.e., decoction). These studies confirmed that UAE is a promising rapid and efficient green technology, which allows to significantly improve the extraction of phenolic compounds compared to other conventional methods [38; 39]. In 2006, [PERSON] and [PERSON] [40] demonstrated the superiority of UAE in extracting phenolics from aromatic plants (such as _Rosmarrius officinalis_, _Vitex aguns-castus_, _Origanum dictammus_, _O. majorana_, _Salvia officinalis_ and _Teucium polium_) over conventional extraction techniques. The content of phenolic compounds extracted in an ultrasonic bath at the