Antioxidant activity, physico-chemical properties, and bioactive compounds of Nigella sativa seeds and oil impacted by microwave processing technique

Strongly anti-oxidant and medicinal, Nigella sativa L (NS) is utilized in conventional medicine to address a range of illnesses, including gastrointestinal, inflammatory and rheumatic illnesses. This study was carried out to investigate the effects of microwave processing on the physico-chemical properties of Moroccan-grown Nigella sativa seeds and oils, as well as to investigate the antioxidant qualities of black cumin oils under conditions of accelerated oxidation. The study's specific goal was to ascertain the effects of varying microwave power levels (500 and 750 W) and roasting times (5, 10, and 15 min) on the black cumin oils' quality indices, fatty acid and sterol content, carotenoid and chlorophyll levels, mineral profile, tocopherol amount, and overall antioxidant activity. To this end, the seeds of black cumin were roasted at two power levels (500 and 750 W) and for three different periods (5, 10, and 15 min) in a microwave oven. The obtained results show that the duration and the processing power did not significantly influence the amount of sterols and fatty acids. In contrast, the quality indices, physico-chemical properties, carotenoid and chlorophyll contents, mineral profile, and tocopherol amount were influenced by the microwave processing. A significant decline in the antioxidant activity was recorded from 45.01 ± 0.81 % (unroasted cumin seeds) to 4.32 ± 0.91 % (750 W/5 min). Based on these findings, the black cumin oil preparations should be handled carefully and the oil must be protected once extracted. The stability and preservation of antioxidants are crucial steps against pro-oxidant and inflammatory conditions that could favour cellular senescence and accelerate aging processes.

Effect of seed's geographical origin on cactus oil physico-chemical characteristics, oxidative stability, and antioxidant activity

The aim of this study was the valorisation of cactus (or prickly pear, Opuntia ficus-indica) seeds growing in six different regions of Morocco. Moisture, proteins, lipids profile, total polyphenols content, oxidative stability, and antioxidant activity were investigated. The Folin-Ciocalteu test highlighted the abundant presence of phenolic compounds (165 to 225 mg EAG/100 g of extract) and a significant antioxidant capacity against DPPH free radicals. The seeds contained protein (7-9.25%) and lipids (2.7-5%). Cactus oil quality indices such as acidity and peroxide value were below 1.2% and 10 mEq.O2/kg, respectively. GC analysis revealed that linoleic and oleic acid percentages ranged from 57.1 to 63.8%, and 13.5 to 18.7%, respectively. Cactus seed oil was rich in tocopherols (500-680 mg/kg) and phytosterols (8000-11,100 mg/kg) with a predominance of γ-tocopherols and β-sitosterol. Triacylglycerols, fatty acids and sterols composition showed small variation depending on the geographical origin, while the individual tocopherol profile was significantly influenced.

Valorization of saffron (Crocus sativus L.) stigma as a potential natural antioxidant for soybean (Glycine max L.) oil stabilization

Synthetic antioxidants are known for their efficiency to improve vegetable oil oxidative stability. But owing to their harmful effects on human health, edible oil industry is seeking for safe and healthy natural antioxidants. The present work was setup with the aim of improving soybean oil (SO) oxidative stability by using saffron (Crocus sativus L.) stigmas collected in Morocco. Saffron stigmas were used as a natural antioxidant at various concentrations (0.2, 0.3, and 0.6%) in soybean oil compared to tocobiol (0.3%) as a synthetic antioxidant (the positive control). Performances of such natural and synthetic antioxidants were evaluated by measuring oil basic quality indices under accelerated storage at 60 °C for 12 weeks. Such indices consisted of free fatty acids (FFA), peroxide value (PV), anisidine value (p-AV), total oxidation value (TOTOX), UV extinction coefficients (K232 and K270), fatty acids composition (FA), and iodine value (IV). The obtained data show that there were significant (p < 0.05) increases in FFA, PV, p-AV, K232, K270, and TOTOX but no much variations were observed for FA and IV especially in saffron stigmas fortified oils across storage times. However, in the case of oils fortified with saffron stigmas at different doses, such an increase was of a lesser magnitude (for FFA, PV, p-AV, K270, and TOTOX) as compared to tocobiol. These outcomes were confirmed by principal component analysis with strong positive correlations (p < 0.001) among FFA, PV, p-AV, K232, K270, and TOTOX. The most important, for which determination coefficient R2 > 0.9, were modeled through simple regressions. In conclusion, saffron stigmas with the different doses performed better than the positive control (tocobiol) regardless of the storage time. It could be concluded that saffron stigmas are a promising natural antioxidant, alternative to synthetic antioxidants, to enhance the oxidative stability of edible oils.

Combined Effects of Domestication and Extraction Technique on Essential Oil Yield, Chemical Profiling, and Antioxidant and Antimicrobial Activities of Rosemary (Rosmarinus officinalis L.)

We aimed at comparing the effects of domestication and extraction technique on the chemical profiling and antioxidant and antimicrobial activities of Rosmarinus officinalis essential oil (ROEO). This was isolated from wild (WR) and cultivated rosemary (CR) using microwave-assisted extraction (ME) and Clevenger hydrodistillation (CH). Domestication was the main variability source in ROEO constituents, while yield was equally determined by domestication and extraction techniques. Our results revealed important variations, owing to domestication and isolation technique, in terms of ROEO yield (1.10–2.85%), major compounds: α-pinene (14.07–42.03%), camphene (2.26–8.19%), β-pinene (0.35–3.76%), α-terpinene (0.55–2.92%), p-cymene (1.22–4.18%), limonene (0.64–2.79%), 1,8-cineole (31.73–40.72%), β-myrcene (2.09–3.2%), linalool (0.22–1.94%), camphor (12.12–19.66%), borneol (0.53–1.67%), and α-terpineol (1.46–7.45%) as well as minimal inhibitory concentration (MIC, 6.17–15.50 μg/mL), and antioxidant activity (IC50, 2.61–8.58 mg/mL). WR performed better in terms of yield, limonene, cineole, camphor, MIC, and IC50, while the remaining compounds were better expressed in CR. ME displayed high records of ROEO traits except for limonene, camphor, and verbenone (better expressed in CH). Principal component analysis confirmed the obtained findings via the separation of WR, CR, and techniques through the first two components (over 93% of data variability). In conclusion, R. officinalis domestication results in differentiated effects on ROEO traits, fostering a better accumulation of some compounds but reducing yield of other compounds and therefore antioxidant along with antimicrobial activity. ME could be recommended as a green method for ROEO isolation since it was more efficient in terms of the investigated ROEO traits.

Chemical Characterization of Date Seeds (Phoenix dactylifera L.) Cultivated in Algeria for its Application as Functional Ingredients

Seven date seeds cultivars, Deglet Nour, Degla Baïdha, Fakht, Ghars, Hamraya, Tafezouin and Takermost were provided from Algerian Sahara. Some of these Algerian date seeds were studied for the first time (Fakht, Hamraya and Takermost). The biochemical characterization of these date seeds were studied, including fatty acids and minerals profiles. The results showed that date seeds are a good source of carbohydrates and crude cellulose, with averages of 66.63 and 13.20%, respectively. They are also a good source of proteins, with the cultivar Deglet Nour seeds as the richest one (9.27 ± 0.03%). The main fatty acid for all date seeds oils is oleic acid except for Deglet Nour in which lauric acid is the main one. However, the studied date seed oils could be classified as oleic-lauric oil. Potassium was the highest mineral in all date seeds cultivars, with values ranging from 2700 to 2900 mg/Kg, followed by sodium and iron. These results indicate that date seeds have good nutritional value with different compositions among cultivars. It could be concluded that date seeds could be considered as a good opportunity for their technological and industrial valorization.

Physical Fruit Traits, Proximate Composition, Antioxidant Activity, and Profiling of Fatty Acids and Minerals of Wild Jujube (Ziziphus lotus L. (Desf.)) Fruits from Eleven Moroccan Origins

This study aimed at investigating the effects of geographical origin on physical fruit traits, proximate composition, fatty acid, and elemental profiling of Moroccan wild jujube (Ziziphus lotus) fruits. Likewise, solvent effects on total phenolic content (TPC), total flavonoid content (TFC), tannin content, and antioxidant activity were also studied. Fruits were sampled from eleven sites where the species grows widely across Morocco (Tafraoute, Taroudant, Zagora, Rhamna, Beni Mellal, Zaouit Cheikh, Khenifra, B-Jaad, Lkhmissat, Sidi Hrazm, and Taounat). Physical fruit traits (length, width, and weight), proximate composition, and minerals were investigated. Fatty acid profiling of extracted oil was also evaluated. TPC and TFC as well as antioxidant activity (ABTS, DPPH, and FRAP) were determined on four different extracts, namely, ethanol extract (EE), methanol extract (ME), acetone extract (AE), and water extract (WE). Our outcomes revealed significant differences ( $p<0.05$ ) among different origins for the measured fruit traits including ash (1.69–2.31%), moisture (2.56–5.69%), proteins (2.63–4.64%), oil (1.59–2.91%) and carbohydrates (86.82–89.20%). The most abundant minerals were K (548.93–828.44 mg/100 g) and Ca (137.50–211.78 mg/100 g). Major fatty acids were oleic acid (50.65 –60.25%), palmitic acid (12.03–18.67%), and linoleic acid (12.63–17.21%). Acetone performed better in terms of TPC (12.77–21.67 mg GAE/g DM), TFC (11.00–18.92 mg QE/g DM), and antioxidant activity using ABTS (22.96–29.32 mg TE/g DM), DPPH (27.96–96.64%), and FRAP (8.37–37.59 mg AAE/g DM). In conclusion, Z. lotus fruit could be considered as a source of carbohydrates and minerals and also natural antioxidants.

Mineral Profiling of Twenty Wild and Cultivated Aromatic and Medicinal Plants Growing in Morocco

Aromatic and medicinal plants (AMPs) have attracted a considerable attention owing to their medicinal and nutritional value. The main research focus in AMPs is devoted to bioactive compounds and related biological activities; however, little is known about their mineral profiling, hence the novelty of this work, which aims at investigating the mineral composition of 20 species of AMPs belonging to 10 botanical families growing in Morocco. Mineral profiling was determined using an inductively coupled plasma optical emission spectrometer in various plant parts depending on each species. Wide variations were found in mineral content among the studied plants. Major elements were K (3987.49 ± 319.01-36,707.01 ± 2936.56 mg/kg), Ca (862.54 ± 69.86-32,836.15 ± 2626.89 mg/kg), P (1065.77 ± 86.33-6328.83 ± 506.32 mg/kg), Mg (986.96 ± 79.66-4935.41 ± 394.82 mg/kg), and Na (28.21 ± 2.23-5792.26 ± 463.38 mg/kg). Fe (62.09 ± 4.96-1636.24 ± 130.89 mg/kg), Mn (10.63 ± 0.85-124.72 ± 9.85 mg/kg), B (5.64 ± 0.45-71.33 ± 5.71 mg/kg), Zn (8.94 ± 0.72-47.01 ± 3.76 mg/kg), and Cu (2.06 ± 0.14-15.12 ± 1.20 mg/kg) were detected at minor levels. Most of the investigated plants were shown to be good sources of minerals. Important correlations were found among different minerals. These outcomes were confirmed by principal component analysis, which separate among studied plants and minerals through the first two principal components. According to obtained results, the studied plants could provide a new promising source of necessary minerals for human diet as well as other various applications.

Proximate Composition, Physicochemical, and Lipids Profiling and Elemental Profiling of Rapeseed (Brassica napus L.) and Sunflower (Helianthus annuus L.) Grown in Morocco

We investigate and compare the nutritional and physicochemical properties of rapeseed and sunflower grown in Morocco. In order to examine a complete physicochemical characterization, various parameters such as mineral profile, fatty acid composition, sterols contents, total flavonoids content (TFC), total polyphenols content (TPC), and quality oil parameters were evaluated. The results showed a relatively small difference in the physicochemical composition of the seeds, as sunflower seeds recorded higher amounts of protein and oil content (22.98 ± 0.01 g/100 g and 41.30 ± 0.50 g/100 g) than rapeseed (22.98 ± 0.01 and 38.80 ± 0.50), while mineral elements profile was observed to be statistically different. Nevertheless, both seeds were rich in K, Ca, P, Mg, and Na and they were relatively poor in Na, Fe, Mn, Cu, and Zn. The most represented macroelement was K with the amount of 7936.53 ± 63.87 mg/Kg in rapeseed and 7739.22 ± 59.50 mg/Kg in sunflower. On the other hand, Cu was present in the analyzed samples the least, mostly below 20 mg/kg. For TPC and TFC, the sunflower recorded higher values (49.73 ± 0.50 and 25.37 ± 0.39 mg GAE/g) than rapeseed (38.49 ± 0.24 and 22.55 ± 1.76 mg QE/g). The fatty acid composition showed that both extracted oils have beneficial proprieties, as they are rich in unsaturated fatty acids; namely, rapeseed oil contains a high level of oleic acid (C18 : 1) (62.19%), while sunflower oil was richer in linoleic acid (C18 : 2) (55.7%). As a result, we conclude that the studied varieties have major importance in terms of both nutritional and seed improvement potentials.

Date Fruit (Phoenix dactylifera L.) Cultivar Extracts: Nanoparticle Synthesis, Antimicrobial and Antioxidant Activities

The pharmaceutical research sector’s inability to produce new drugs has made it difficult to keep up with the rate at which microbial resistance is developing. Recently, nanotechnology and its combinations with natural products have been the saviors against multidrug resistant bacteria. In the present investigation, different Egyptian and Saudi date cultivars were extracted and then phytochemically analyzed and tested for possible antimicrobial activities against multidrug resistant (MDR) microbes. The results revealed that extract of the flesh of fresh “Hayany” fruit (Egyptian date) showed the highest antimicrobial activity, with high levels of phenolic, flavonoid, and tannin concentrations (538.578 µg/mL, 28.481 µg/mL, and 20.888 µg/mL, respectively) and high scavenging activity, with an IC50 reaching 10.16 µg/mL. The highest synergistic activity was found between fresh “Hayany” fruit extract and amikacin. Novel nano-fresh fruit of “Hayany” date extract was synthesized using a ball-milling technique. The vesicle size was 21.6 nm, while the PDI and zeta potential were 0.32 and +38.4 mV, respectively. The inhibition zone diameters of nano-fresh fruit of “Hayany” date extract/amikacin reached 38 mm and 34 mm, with complete microbial eradication after 9 h and 6 h, against Candida albicans and Staphylococcus aureus, respectively. In conclusion, date fruit extract could be used as a candidate bioactive compound in the fight against infectious diseases.

Seed Phytochemical Profiling of Three Olive Cultivars, Antioxidant Capacity, Enzymatic Inhibition, and Effects on Human Neuroblastoma Cells (SH-SY5Y)

This work evaluated the phytochemical composition of olive seed extracts from different cultivars (‘Cobrançosa’, ‘Galega’, and ’Picual’) and their antioxidant capacity. In addition, it also appraised their potential antineurodegenerative properties on the basis of their ability to inhibit enzymes associated with neurodegenerative diseases: acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and tyrosinase (TYR). To achieve this goal, the phenolic composition of the extracts was determined through high-performance liquid chromatography coupled with photodiode-array detection and electrospray ionization/ion trap mass spectrometry (HPLC-DAD-ESI/MSⁿ). The antioxidant capacity was assessed by two different methods (ABTS^•+ and DPPH^•), and the antineurodegenerative potential by the capacity of these extracts to inhibit the aforementioned related enzymes. The results showed that seed extracts presented a high content of phenolic compounds and a remarkable ability to scavenge ABTS^•+ and DPPH^•. Tyrosol, rutin, luteolin-7-glucoside, nüzhenide, oleuropein, and ligstroside were the main phenolic compounds identified in the extracts. ‘Galega’ was the most promising cultivar due to its high concentration of phenolic compounds, high antioxidant capacity, and remarkable inhibition of AChE, BChE, and TYR. It can be concluded that olive seed extracts may provide a sustainable source of bioactive compounds for medical and industrial applications.

Date fruit as a promising source of functional carbohydrates and bioactive compounds: A review on its nutraceutical potential

From the past decade, consumption of ready-to-eat food and ease of access to fast food increased the onset of several diseases. Thus, there is a need to shift the trend from consumption of unhealthy food item to natural and healthy alternatives. In this context, fruits can be considered as functional food, which have ability to provide essential nutrients and bioactive compounds. These compounds when consume in adequate amount would have the potential to lower the onset of diseases. In this regard, Phoenix dactylifera or date fruit is an important source of functional carbohydrates and bioactive compounds for their use as functional foods. The major functional carbohydrate in date fruit are in the form of dietary fiber, such as β-glucan, cellulose and fructans along with other bioactive compounds. Additionally, it is also a good source of other important nutrients such as sugars, minerals, along with minor quantities of proteins and lipids. Due to these functional compounds, date fruit have shown a wide range of pharmaceutical properties such as antioxidant, anti-inflammatory, anti-diabetic, hepatoprotective and anticancer. This review provides latest information regarding functional and nutraceutical carbohydrates of date fruits along-with mechanism of action on different diseases reported in recent years. PRACTICAL APPLICATIONS: This will provide information to food industries for the development of innovative food products by using date fruit. Moreover, bioactive components from date fruit may prove to enhance global health and wellness. However, further research is needed on clinical trials for the development of functional food products by using date fruit for functional foods and pharmaceutical applications.

Comparative Assessment of Phytochemical Compounds and Antioxidant Properties of Kernel Oil from Eight Sour Cherry (Prunus cerasus L.) Cultivars

New plant oils as a potential natural source of nutraceutical compounds are still being sought. The main components of eight cultivars (‘Koral’, ‘Lucyna’, ‘Montmorency’, ‘Naumburger’, ‘Wanda’, ‘Wigor’, ‘Wołyńska’, and ‘Wróble’) of sour cherry (Prunus cerasus L.) grown in Poland, including crude fat, protein, and oil content, were evaluated. The extracted oils were analysed for chemical and biological activity. The oils had an average peroxide value of 1.49 mEq O₂/kg, acid value of 1.20 mg KOH/g, a saponification value of 184 mg of KOH/g, and iodine value of 120 g I₂/100 g of oil. The sour cherry oil contained linoleic (39.1–46.2%) and oleic (25.4–41.0%) acids as the major components with smaller concentrations of α-eleostearic acid (8.00–15.62%), palmitic acid (5.45–7.41%), and stearic acid (2.49–3.17%). The content of sterols and squalene varied significantly in all the studied cultivars and ranged between 336–973 mg/100 g and 66–102 mg/100 g of oil. The contents of total tocochromanols, polyphenols, and carotenoids were 119–164, 19.6–29.5, and 0.56–1.61 mg/100 g oil, respectively. The cultivar providing the highest amounts of oil and characterised by the highest content of PUFA (including linoleic acid), plant sterols, α-and β-tocopherol, as well as the highest total polyphenol and total carotenoids content was been found to be ‘Naumburger’. The antioxidant capacity of sour cherry kernel oils, measured using the DPPH^• and ABTS^•+ methods, ranged from 57.7 to 63.5 and from 38.2 to 43.2 mg trolox/100 g oil, respectively. The results of the present study provide important information about potential possibilities of application of Prunus cerasus kernel oils in cosmetic products and pharmaceuticals offering health benefits.