The aim of this study was to evaluate an advanced water extraction method applying pulsed electric field followed by ultrasound. For this purpose, antioxidant capacity (AC) and total phenolic content (TPC) of Olea europaea L. leaves and unripe fruit, Melissa officinalis L. leaves, Cistus incanus L. ssp. creticus leaves, Vitis vinifera L. cv. “Xinomavro” leaves, marc, and fruits, Aronia melanocarpa L. fruits, Punica granatum L. peel, and Crocus sativus L. petals were analyzed. The results showed that a ratio of 1/20 g plant material/ml water, 5 min pulsed electric field and 30 min ultrasounds presented the maximum extraction efficiency. Melissa officinalis L. and Punica granatum L. had high TPC exhibiting 155 mg GAE/g DW (DW: dry weight) and 208 mg GAE/g DW, respectively, comparing to Vitis vinifera L. marc (31 mg GAE/g DW). All aqueous extracts studied, had high AC approaching 90% (except 32% in Crocus sativus L. petals and Vitis vinifera L. marc). Practical applications The beneficial use of medicinal and aromatic plants extracts in human health has been widely accepted. However, the efficiency of the process for the extraction of phenolic compounds from plants constitutes a challenge, since it is highly depended on the applied technique itself and the imposed operating conditions. In this regard, this work studies the application of a novel combined process of pulsed electric field extraction followed by ultrasounds assisted extraction for the recovery of polyphenols from selected Mediterranean plants. The evaluated process showed high extraction yields at short processing time and at moderate temperatures, which in conjunction with the use of water as a “green” extraction solvent lead to bioactive compounds stability and increased applicability of aqueous extracts.

In this study, the assessment of TPC and antioxidant activity enhancement of medicinal and aromatic plant (MAP) aqueous extracts using natural sweeteners or encapsulation materials was carried out. MAP extracts fortified with polyphenols were used to produce biofunctional chocolate bites. Honey or erythritol added to Melissa officinalis concentrated aqueous extracts exhibited TPC at 19.53 mg GAE/mL and 18.24 mg GAE/mL, respectively, and DPPH radical scavenging activity greater than 82%, comparing to its non-concentrated aqueous extract (3.74 mg GAE/mL and 72.9%, respectively). Honey added to MAP concentrated aqueous extract mixtures presented up to twofold higher TPC compared to M. officinalis concentrated aqueous extracts with honey. Chocolate bites with MAP concentrated aqueous extract mixtures and honey exhibited TPC and DPPH radical scavenging activity at 29.48 mg GAE/g chocolate and 93.7%, respectively. The addition of gum arabic or inulin in MAP concentrated aqueous extract mixtures increased the TPC up to 12-fold (40.37 mg GAE/mL and 34.14 mg GAE/mL, respectively) compared to its non-concentrated aqueous extracts (3.38 mg GAE/mL), whereas DPPH radical scavenging activity approached 99.5%. Honey incorporation as a sweetener and polyphenolic compound encapsulation in gum arabic can lead to the production of biofunctional foods with elevated cytoprotective action without compromising their organoleptic attributes.

Cross border areas face common challenges on water management, such as monitoring water demands and quality, because they share a common water basin for covering their water needs. This paper presents the first results of a new, accurate, sensitive and functional tool for assessing water quality, taking under consideration legislation and expert’s opinion, created in frame of the SAVE-WATER, Interreg IPA II Cross-border Cooperation Programme Greece-Albania 2014-2020. The project addresses the open problems and challenges by promoting a transnational common strategy for drinking water management and a shared management policy among three Greek and two Albanian cross border regions.

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Chromium occurs in nature mainly in its trivalent or hexavalent form. Hexavalent chromium Cr(VI) is particularly toxic to humans, animals, and plants. The extensive pollution of groundwaters with Cr(VI) necessitates the complete understanding of natural chromium oxidation and reduction mechanisms, both for assessing the risk of hexavalent chromium formation and for the development of techniques for the reduction and removal of Cr(VI) from contaminated water bodies. In this work, the possibility of hexavalent chromium reduction by discarded or low-cost materials, which contain reducing compounds, is investigated regarding the creation of a compact, pump-and-treat filter for Cr(VI) removal from groundwater.