Salah A. Al Maiman

The present study aimed to investigate the total phenolics, total flavonoids, and antioxidant activity in terms of the DPPH scavenging, reducing power, and H₂O₂ scavenging of the aerial parts of onion, white radish, red radish, carrot, and beet as affected by different extraction solvents. Generally, the aerial part of these vegetables has high antioxidant properties. Samples were extracted with methanol (100 and 70%), ethanol (100 and 70%), and water. Total phenolic content was highest when the samples were extracted using 100% methanol, while extraction with 100% ethanol yielded the highest total flavonoids. The highest DPPH activity and H₂O₂ scavenging values were obtained by extraction of the aerial plant parts with 70% ethanol, and the 70% methanol extract had the highest reducing power. Partial least regression (PLS) was performed to validate the optimum solvent for extraction of the antioxidants and their activity in each plant. The PLS indicated that there was a variation in the validation of the different extracts for each plant. The high antioxidant capacity of root vegetables, which is natural, indicates that they may have health and dietetic advantages for consumers.

This investigation was conducted to test the potential of the galactomannan (F-GAL) and aqueous extract (FS-AE) of the Fenugreek seed aqueous to prevent liver and kidney damage extracts in streptozotocin (STZ)-induced T1DM in rats. Non-diabetic and diabetic rats received the normal saline as a vehicle or were treated with FS-EA or F-GAL at a final concentration of 500 mg/kg/each. Treatments with both drugs reduced fasting hyperglycemia and improved serum and hepatic lipid profiles in the control and diabetic rats. Additionally, F-GAL and FS-AE attenuated the associated reduction in the mass and structure of the islets of Langerhans in diabetic rats and improved the structure of the kidneys and livers. In association, they also reduced the generation of reactive oxygen species (ROS), lipid peroxides, factor (TNF-α), interleukin-6 (IL-6), and nuclear levels of NF-κB p65, and improved serum levels of ALT, AST, albumin, and creatinine. However, both treatments increased hepatic and renal superoxide dismutase (SOD) in the livers and kidneys of both the control and diabetic-treated rats, which coincided with a significant increase in transcription, translation, and nuclear localization of Nrf2. In conclusion, FS-AE and F-GAL are effective therapeutic options that may afford a possible treatment for T1DM by attenuating pancreatic damage, hyperglycemia, hyperlipidemia, and hepatic and renal damage.

This study investigated the chemical changes of phytochemicals and antioxidant activity during the preparation of traditional Sudanese asida prepared from gamma-radiated (1.0 and 2.0 kGy) flour of two sorghum cultivars (Tabat and Wad Ahmed). For both cultivars, the irradiation process significantly (p < 0.05) increased the total phenolic content and antioxidant activity of the raw flour, while it caused a significant reduction in total flavonoid content and tannin content. Traditional asida (fermented food) prepared from irradiated sorghum flour caused a significant reduction in TPC, TFC, and tannin content in both sorghum cultivars, while the antioxidant activities (DPPH, reducing power, and H₂O₂ scavenging) were significantly increased in both the Tabat (85.0%, 3.8 mg AAE/g, and 84.6%, respectively) and the Wad Ahmed (89.6%, 3.9 mg AAE/g, and 83.1%, respectively) sorghum cultivar grains, particularly in those processed from 2.0 kGy-irradiated flour. A positive high correlation was observed between gamma radiation (2.0 kGy) and the antioxidant activity of asida prepared from both cultivars. In conclusion, traditional fermented asida obtained from irradiated flour showed high antioxidant activity in both sorghum cultivars.

This study was conducted to investigate the effect of boiling and roasting treatments on the phenolic and flavonoid contents and antioxidant activity of pod shells of two Sudanese peanut cultivars, Sodari and Ghabiash. The samples were subjected to a boiling process (1:5 w/v; 20 g/100 mL) at 100 °C for 45 min and a roasting treatment at 180 °C for 30 min. Results revealed that both cultivars are rich in phenolic compounds with high antioxidant activity in their shell. The boiling and dry roasting treatments significantly (p < 0.05) enhanced the total phenolic content, total flavonoid content, and antioxidant activity of the peanut shell for both peanut cultivars. The shells of Ghabiash peanut cultivar exhibited higher bioactive properties than the shells of Sodari cultivar, in which these properties were highly improved by roasting and boiling treatments. In general, peanut shells can serve as an important underutilized by-product, particularly after roasting treatment, for potential applications in food formulations.

Effects of fermentation on the chemical composition, mineral, total phenolic, total flavonoid, tannin, vitamin C, total carotenoid content, and antioxidant activity of “Nabag” Ziziphus spina-christi (L.) seeds were investigated. The fermentation process was carried out for 6, 12, 24, and 48 h. The fermentation significantly (p < 0.05) improved the chemical composition and mineral content of “Nabag” seeds, particularly the Ca, Fe, and Zn content. The phenolic, vitamin C, total carotenoid content, and antioxidant activity were significantly (p < 0.05) increased as a result of fermentation compared with unfermented Ziziphus spina-christi (L.) seeds. Fermentation of the seeds for 48 h resulted in the highest increase in crude fiber, Ca, Fe, Zn, and bioactive compounds. These results indicate the potential utilization of fermented “Nabag” seeds in the production and formulation of functional foods rich in crude fiber, essential minerals, and bioactive compounds.

This study investigated the effect of solar drying on storability and physiochemical and antioxidant capacities of dried tomatoes. Sliced fruit was dried at 45 ± 2 °C for 24 h under a solar tunnel dryer and stored at ambient temperature for 90 and 180 days. Solar drying treatments significantly (p < 0.05) reduced the bacterial and mold load, and eliminated Staphylococcus aureus, S. saprophyticus, and Escherichia coli in all samples. Solar drying treatment reduced the water activity of the dried tomato’s to 0.31 that remained at the same level during storage period 180 days. Storage of dried tomato slices resulted in the decrease of both color and vitamin C content while it increased the total carotenoid, lycopene, phenolic compound content, and antioxidant activity. Furthermore, the principle component analysis (PCA) revealed that solar drying of tomato slices enhanced its physicochemical properties, antioxidant capacity particularly after storage for 90 and 180 days. Interestingly, the solar drying process enhanced tomato slices storage and physicochemical characteristics, that resulted in extending the shelf life by up to 6 months, indicating the great potential application of low-tech solar in food industry and could become an emerging effective post-harvest preservative method for seasonal perishable vegetable and fruit, particularly in developing countries.

The present study aimed to determine the role of Salvia hispanica L., (chia seed) fatty acid content in adipocyte lipid accumulation and human macrophage immunoregulatory potential. Chia seed fatty acid was extracted using hexane by the cold percolation method. A gas chromatography-mass spectrometry (GC-MS) analysis showed a 3:1 ratio of omega 3 and omega 6 fatty acid composition and it was more beneficial for human health. We treated it with increasing concentrations (0–6.4 μg/mL) of chia seed fatty acid extract to determine the cytotoxicity on the preadipocytes and macrophage; no significant cytotoxicity was observed. Chia seed, in 0.2 and 0.4 μg/mL doses, significantly arrested adipocyte hypertrophy and macrophage foam cell development. The gene expression levels of adipocyte confirmed the increased expression of adipocyte mitochondrial thermogenesis related genes, such as uncoupling protein-1 (UCP-1), peroxisome proliferator activated receptor gamma coactivator 1 alpha (PPARγC1α) and PR domain containing 16 (PRDM16); and the down regulated expression of the lipid synthesis related gene sterol regulatory element binding of protein-1c (SREBP-1c). In addition, adipogenesis related genes, such as the proliferator activated receptor γ (PPARγ) and CCAAT/enhancer binding protein (C/EBPα) expressions, have been down regulated by chia seed treatment. Macrophage treated with chia seed-treated adipocyte condition media significantly inhibited the obesity associated inflammatory genes and protein expression levels, such as monocyte chemo attractant protein-1 (MCP-1), prostaglandins E2, interleukin-6, plasminogen activator inhibitor-1 (PAI-1) and tumor necrosis factor-α (TNF-α). In conclusion, a 3:1 ratio of omega 3 and omega 6 fatty acid composition of chia seed fatty acid content potentially inhibits lipid accumulation, and enhanced fatty acid oxidation, via UCP-1 and PRDM16 expression. Macrophage recruitment to adipocyte and the development of obesity associated inflammation was suppressed by chia seeds.