Citrus species are one of the world’s popular fruit crops, cultivated all over the world for their economic and nutritional values. Citrus, like other fruits and vegetables, are an important source of several antioxidant molecules (polyphenols, ascorbic acid, and carotenoids) that can inhibit the harmful effects of free radicals on the human body; due to their functional values and health-promoting properties, Citrus species are considered valuable fruits not only in agri-food industry, but also in pharmaceutical industry. Flavonoids are among the major constituents of polyphenols found in different parts of Citrus fruits (skin, peels, seed, pulp membrane, and juice). Flavonoids have different biological properties (antiviral, antifungal, and antibacterial activities). Several studies have also shown the health-related properties of Citrus flavonoids, especially antioxidant, anticancer, anti-inflammation, anti-aging, and cardiovascular protection activities. In the present review, attempts are made to discuss the current trends of research on flavonoids in different Citrus species.

Almond (Prunus dulcis (Mill.) D.A. Webb) is one of the most important nut crops both in terms of area and production. Over the last few decades, an important part of the beneficial actions for health associated with their consumption was attributed to the phenolic compounds, mainly accumulated in almond skin. Interestingly, after cold-pressed oil extraction, most of these antioxidant phenolic compounds are retained in a skin-enriched by-product, a so-called almond cold-pressed oil residue. In Morocco, the fifth highest ranking producer in the world, this production generates an important part of this valuable byproduct. In the present study, using a multivariate Box–Behnken design, an ultrasound-assisted extraction method of phenolic compounds from Moroccan almond cold-pressed oil residue was developed and validated. Response surface methodology resulted in the optimal extraction conditions: the use of aqueous ethanol 53.0% (v/v) as a green solvent, applying an ultrasound frequency of 27.0 kHz for an extraction duration of 29.4 min. The present ultrasound-assisted extraction allowed substantial gains in terms of extraction efficiency compared to conventional heat reflux extraction. Applied to three different local Beldi genotypes growing at three different experimental sites, the optimal conditions for ultrasound-assisted extraction led to a total phenolic content of 13.86 mg/g dry weight. HPLC analysis revealed that the main phenolic compounds from this valuable byproduct were: chlorogenic acid followed by protocatechuic acid, p-hydroxybenzoic acid, and p-coumaric acid. The accumulation of these phenolic compounds appeared to be more dependent on the genetic background than on the environmental impact here represented by the three experimental culture sites. Both in vitro cell free and cellular antioxidant assays were performed, and revealed the great potential of these extracts. In particular, correlation analysis provided evidence of the prominent roles of chlorogenic acid, protocatechuic acid, and p-hydroxybenzoic acid. To summarize, the validated ultrasound-assisted extraction method presented here is a quick, green, simple and efficient for the possible valorization of antioxidant phenolic compounds from Moroccan almond cold-pressed oil residues, making it possible to generate extracts with attractive antioxidant activities for future nutraceutical and/or cosmetic applications.

SummaryThe quality of the oil of four safflower varieties, originating from Spain (Rancho), India (Sharda) and Morocco (Cartamar and Cartafri), which were cultivated at the experimental station in Oujda (a semi-arid region of eastern Morocco) was evaluated through analysis of their phenolic and carotenoid contents. The composition of the phenolic compounds of safflower oil has not yet been documented. Therefore, in this preliminary study, Thirty different phenolic compounds were identified, and significant differences between the oil varieties were observed (P < 0.05). In the seed oil from the Rancho and Sharda safflower varieties, the main phenolic compound was trans-chalcone, representing 13.45% and 11.8%, respectively, of the total phenolics, whereas in Cartamar and Cartafri oils, naringin accounted for 26.82% and 16.5%, respectively, of the total phenolics. The total carotenoid contents ranged from 1.13 mg kg À1 (Rancho) to 1.34 mg kg À1 (Cartamar and Cartafri). We observed that b-cryptoxanthin (0.31-0.37 mg kg À1) and b-carotene (0.3-0.35 mg kg À1) were the predominant carotenoids in all of the safflower oils that were studied.Keywords Carotenoids, eastern Morocco, oil quality, phenolic compounds, safflower. IntroductionThe safflower (Carthamus tinctorius L) is an oilseed crop, which for many years has been grown in relatively small areas of northern and middle-eastern Africa (Purdy et al., 1959). The safflower is a taprooted annual crop that can tolerate environmental stresses, including salinity and water stresses (Lovelli et al., 2007). Therefore, this crop could have a good yield potential in Morocco's semi-arid areas. The Moroccan research of this crop mainly focused on its breeding, starting in the early 1960s (Nabloussi & Boujghagh, 2006).Safflower oil (Carthamus tinctorius L.) has a high content of polyunsaturated linoleic acid and tocopherol and is produced for nutritional as well as for medicinal uses (Fernandez-Martinez et al., 1993).Secondary metabolites are a subject of increasing research interest. This is particularly true for plant polyphenols that are widely used in therapy due to their vasculoprotective, anti-inflammatory, enzyme-inhibitory, antioxidant and radical-scavenging properties (Bahorun et al., 1996).The quality of vegetable oil depends on several factors, including the plant variety, the degree of its maturation, pedoclimatic factors, farming practices, the oil-extraction method utilised and the storage conditions (Matos et al., 2007). Safflower oil has been characterised in different regions of the world, and several experiments have demonstrated variability in its composition due to the soil and climatic conditions. Thus, the introduction of a new crop in a regional farming system such as that in north-eastern Morocco requires information concerning its performance under the local environmental conditions.The aim of the present work was to complete our previous investigation focused on characterising safflower seeds produced in north-eastern Morocco (Ben Moumen et al., 2013a,b)...

Almond (Prunus dulcis (Mill.) D.A.Webb) is one of the largest nut crops in the world. Recently, phenolic compounds, mostly stored in almond skin, have been associated with much of the health-promoting behavior associated with their intake. The almond skin enriched fraction obtained from cold-pressed oil residues of the endemic Moroccan Beldi ecotypes is particularly rich in chlorogenic acid. In this study, both almond skin extract (AE) and chlorogenic acid (CHL) supplements, similar to traditional positive control resveratrol, significantly increased the chronological life-span of yeast compared to the untreated group. Our results showed that AE and CHL significantly reduced the production of reactive oxygen and nitrogen species (ROS/RNS), most likely due to their ability to maintain mitochondrial function during aging, as indicated by the maintenance of normal mitochondrial membrane potential in treated groups. This may be associated with the observed activation of the anti-oxidative stress response in treated yeast, which results in activation at both gene expression and enzymatic activity levels for SOD2 and SIR2, the latter being an upstream inducer of SOD2 expression. Interestingly, the differential gene expression induction of mitochondrial SOD2 gene at the expense of the cytosolic SOD1 gene confirms the key role of mitochondrial function in this regulation. Furthermore, AE and CHL have contributed to the survival of yeast under UV-C-induced oxidative stress, by reducing the development of ROS/RNS, resulting in a significant reduction in cellular oxidative damage, as evidenced by decreased membrane lipid peroxidation, protein carbonyl content and 8-oxo-guanine formation in DNA. Together, these results demonstrate the interest of AE and CHL as new regulators in the chronological life-span and control of the oxidative stress response of yeast.

-The purpose of this study is the evaluation of flavor profiles of monovarietal virgin olive oils (VOO) produced in the Oriental region of Morocco via the characterization of volatile compounds, using SPME-GC/MS technique, and the determination of total phenolic content (colorimetric method). The study concerns oils of three European olive cultivars (Arbosana, Arbequina and Koroneiki) which were recently introduced in Morocco under irrigated high-density plantation system. GC/MS aroma profiles of analyzed VOOs showed the presence of 35 volatile compounds. The major compounds in such oils are C6 compounds produced from linoleic and linolenic acids via lipoxygenase pathway such as trans-2-hexenal, cis-2-hexenal, cis-3-hexen-1-ol, trans-3-hexen-1-ol, trans-3-hexen-1-ol acetate, hexanal and 1-hexanol in different proportions depending on the cultivar (p < 0.05). In addition, statistical analyses indicate that the analyzed VOOs have different aroma profiles. Arbequina oil has a high proportion of compounds with sensory notes "green" and "sweet" giving it a fruity sensation compared to Arbosana and Koroneiki. In parallel, Arbosana and Koroneiki oils are rich in phenolic compounds and provide relatively bitter and pungent tastes to these oils.Keywords: virgin olive oil / volatile compounds / phenols / solid phase micro extraction Résumé -Profils organoleptiques d'huiles d'olive vierges monovariétales produites dans la région orientale du Maroc. Le but de cette étude vise l'évaluation des profils organoleptiques des huiles d'olive vierges monovariétales produites dans la région orientale du Maroc par la caractérisation des composés volatils et la détermination de la teneur en phénols totaux. Il s'agit d'huiles d'olive de trois cultivars d'origine européenne (Arbequina, Arbosana et Koroneiki) récemment introduites au Maroc en irriguée super-intensif. Les profils aromatiques obtenus par GC/MS des huiles analysées montrent la présence de 35 composés volatils. Les principaux composés présents dans ces huiles sont les composés C6, tels que le trans-2-hexénal, le cis-2-hexènal, le cis-3-hexén-1-ol, le trans-3-hexén-1-ol, l'acétate de trans-3-hexén-1-ol, le 1-héxanol et l'hexanal à des proportions différentes selon le cultivar (p < 0,05). En outre, les analyses statistiques indiquent que les huiles analysées ont des profils aromatiques différents. L'huile d'Arbéquina présente une forte proportion des composés offrant des notes sensorielles « vert » et « sucré » lui conférant une sensation de fruité par rapport à l'Arbosana et Koroneiki. En parallèle, les huiles Arbosana et Koroneiki sont riches en composés phénoliques et apportent des goûts relativement amer et piquant à ces huiles.