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Bioactive potential of hazelnut husks was determined as a function of their cultivar source and extraction solvent. Hazelnut husks from four hazelnut cultivars (Butler, Grada de Viseu, Lansing and Morell) were picked in a hazelnut orchard at harvest and extracted with five solvents with different polarity: water, methanol, acetone, ethyl acetate and hexane. Phenolics were identified by HPLC–DAD and antioxidant activity was determined by three complementary methods: DPPH, FRAP and inhibition of lipid peroxidation. A total of 11 phenolics were identified in studied cultivars and grouped in five main classes namely, ellagitannin (ellagic acid), benzoic acids (gallic acid, protocatechuic acid and vanillic acid), flavonols (kaempferol-3,7-O-diglucoside, kaempferol-3-O-[6-acetylglucoside]-7-O-glucoside, kaempferol-3-O-[6acetylglucoside]-7-O-rhamnoside and quercetin-3-O-rutinoside), flavone (luteolin-7-O-rutinoside) and flavan-3-ol (epicatechin). Cultivar and extraction solvent influenced significantly (p

Water scarcity is seriously affecting agricultural production, especially in arid and semi-arid areas. Therefore, there is increasing interest in improving water productivity in agriculture. This research aims to study the effects of deficit irrigation on the productive response of sweet pepper plants. Nine deficit irrigation strategies were assayed during two seasons (2017 and 2018) in a randomised complete block design with three replicates. These irrigation strategies consisted of applying 100%, 75% and 50% of the irrigation water requirement (IWR) during the entire growing period (continued deficit irrigation) or applying 75% or 50% of the IWR during one of the following stages (regulated deficit irrigation): vegetative growth, fruit setting, and harvesting. Pepper plants cultivated under deficit irrigation reduced fruit biomass and indicators of plant water status. Applying water deficits during the vegetative growth and fruit-setting stages had minimal effects on the marketable yield but with minimal water savings. Irrigating pepper plants with 75% or 50% of the IWR during the entire crop cycle or with 50% of the IWR during harvesting resulted in a high incidence of fruits affected by blossom end rot, which in turn, led to a drastic reduction of the marketable yield in relation to fully irrigated plants (− 36%, − 55% and − 44%, respectively). These strategies also recorded the highest soluble solid and phenolic contents. Reducing the water applied to 75% of the IWR at harvesting led to a yield reduction (− 19%) but with important water savings (21%) and acceptable levels of soluble fruit solids and phenolic compounds.

[EN] Response surface methodology (RSM) was chosen to optimize the influence of solvent pH and relative proportion, and time of extraction, regarding polyphenols and radical scavenging capacity of almond (Prunus dulcis (Mill.) D.A. Webb) by-products (hulls, shells, and skins) from an almond orchard located in the North of Portugal (Lousa, Torre de Moncorvo). The RSM model was developed according to a Box-Behnken design and the optimal conditions were set for pH 6.5, 250.0 min, and 90.0% of food quality ethanol, pH 1.5, 235.0 min, and 63.0% ethanol, and pH 1.5, 250.0 min, and 56.0% ethanol for hulls, shells, and skins, respectively. The optimal conditions were obtained applying spectrophotometric techniques because of their versatility, while the chromatographic profile of extracts obtained when applied the optimal conditions indicated the presence of 3-caffeoylquinic acid, naringenin-7-O-glucoside, kaempferol-3-O-glucoside, isorhamnetin-3-O-rutinoside, isorhamnetin-3-O-glucoside, and isorhamnetin aglycone in hulls and skins. The model designed allowed the optimization of the phenolic extraction from almond by-products, demonstrating the potential of these materials as sources of antioxidant compounds with potential industrial, pharmaceutical, and food applications., IP received financial support from the FCT-Portuguese Foundation for Science and Technology (SFRH/BD/52539/2014), under the Doctoral Programme BAgricultural Production Chains-from fork to farm (PD/00122/2012). RDP was supported by a Postdoctoral Contract (Juan de la Cierva de Incorporacion ICJI-2015-25373) from the Ministry of Economy, Industry and Competitiveness of Spain. This work is supported by the National Funds by FCT-Portuguese Foundation for Science and Technology, under the project UID/AGR/04033/2019.