Tarek Alshaal
55621631600
Publications - 11
Optimizing mung bean and soybean hydrolysis for the generation of bioactive peptides of potential functional food applications
Publication Name: Food Chemistry X
Publication Date: 2025-08-01
Volume: 30
Issue: Unknown
Page Range: Unknown
Description:
This study investigates the enzymatic hydrolysis of soybean (Glycine max L.) and mung bean (Vigna radiata) proteins using bromelain, ficin, papain, and pepsin to improve digestibility and functional properties. We hypothesized that mung bean's less compact structure would yield higher degree of hydrolysis (DH) and bioactive peptides compared to soybean, enhancing antioxidant capacity for functional foods. Mung bean showed significantly higher proteolysis, with a maximum DH of 46.5 ± 2.1 % (p ≤ 0.05) using 10 % bromelain for 12 h, versus soybean's 26.9 ± 1.5 % (p ≤ 0.05). Bromelain and ficin outperformed papain and pepsin, producing up to 62.3 ± 3.2 % oligopeptides and 32.4 g/100 g free amino acids in mung bean. Mung bean hydrolysates exhibited superior antioxidant activity, reaching 78.4 ± 2.5 % DPPH scavenging (p ≤ 0.05), compared to soybean's 58.9 ± 2.0 % (p ≤ 0.05), due to increased 200–1000 Da peptides. Optimal conditions (10 % enzyme, 12 h) improved solubility and bioactivity, highlighting mung bean's potential and bromelain's efficacy for sustainable food applications, warranting further protease research.
Open Access: Yes
Comparative Study on Antioxidant Capacity of Diverse Food Matrices: Applicability, Suitability and Inter-Correlation of Multiple Assays to Assess Polyphenol and Antioxidant Status
Publication Name: Antioxidants
Publication Date: 2025-03-01
Volume: 14
Issue: 3
Page Range: Unknown
Description:
Antioxidants play a crucial role in mitigating oxidative stress and preventing cellular damage caused by free radicals. This study aimed to compare the effectiveness of three antioxidant assays—DPPH, TEAC, and FRAP—in quantifying the antioxidant capacity of 15 plant-based spices, herbs, and food materials from five distinct plant families. The relationship between these assays and total polyphenol content (TPC) as well as total flavonoid content (TFC) was also investigated. The results showed that FRAP exhibited the strongest correlation with TPC (r = 0.913), followed by TEAC (r = 0.856) and DPPH (r = 0.772). Lamiaceae species, such as rosemary and thyme, consistently demonstrated high antioxidant activities across all assays. The study highlights the complementary nature of these assays in assessing antioxidant capacity and underscores their utility in profiling polyphenol- and flavonoid-rich plants for potential nutritional and therapeutic applications.
Open Access: Yes
Copper-induced stress responses and phytoaccumulation capacity of three giant reed (Arundo donax L.) ecotypes
Publication Name: Biomass and Bioenergy
Publication Date: 2026-02-01
Volume: 205
Issue: Unknown
Page Range: Unknown
Description:
This study investigated the effects of elevated copper levels on the early-stage growth and development of three Arundo donax (giant reed) ecotypes (STM, BL, and ESP) from different climatic zones, focusing on plant morpho-physiological and copper biochemical changes (including root structure, photosynthetic structure, copper accumulation and translocation, soluble protein, and lipid peroxidation). Plants were grown under increasing concentrations of copper (0, 100, 200, 300, and 400 mg/kg), revealing that copper accumulation was predominantly localized in the roots, with ESP showing the highest at 1829 μg/g, followed by STM (1191 μg/g) and BL (935 μg/g) at 400 mg/kg. While morphological traits like plant height and stem diameter were less affected, root volume decreased significantly at high copper levels (e.g., by 60 % in BL from 10.00 cm3 in control to 4.00 cm3 at 400 mg/kg). Physiological responses varied significantly: photosynthetic pigments increased with moderate copper levels (e.g., chlorophyll a in BL from 31.67 μg/cm2 in control to 49.19 μg/cm2 at 400 mg/kg) but declined at higher concentrations in ESP. Lipid peroxidation, measured by malondialdehyde (MDA), indicated increased oxidative stress, especially in STM and ESP (e.g., root MDA in STM from 14.22 nmol/g in control to 26.30 nmol/g at 400 mg/kg). These results highlight the ESP ecotype's higher tolerance and copper sequestration capabilities, making it a promising candidate for further studies in copper-stressed environments.
Open Access: Yes
From waste to wealth: innovations in the recovery of bioactive compounds from agro-food by-products
Publication Name: European Food Research and Technology
Publication Date: 2026-02-01
Volume: 252
Issue: 2
Page Range: Unknown
Description:
The valorization of food waste biomass for the extraction of bioactive compounds presents a sustainable solution to global food waste challenges while offering significant economic and environmental benefits. This review comprehensively examines advanced green extraction technologies such as ultrasound-assisted extraction (UAE), microwave-assisted extraction (MAE), supercritical fluid extraction (SFE), and enzyme-assisted extraction (EAE) for recovering polyphenols, carotenoids, flavonoids, and other high-value compounds from fruit, vegetable, cereal, and animal-derived waste. Highlighting optimized extraction parameters showed that modern techniques outperform conventional methods in yield, efficiency, and cost-effectiveness, with UAE reducing manufacturing costs by up to 84% compared to Soxhlet extraction. The review also addresses pretreatment strategies, purification innovations (e.g., flash chromatography), and emerging solvents like natural deep eutectic solvents (NADES) with lower environmental impact, higher efficiency, recyclability and biodegradability. Challenges such as contamination risks, temperature sensitivity, and scalability are critically analyzed, alongside future directions integrating nanotechnology, artificial intelligence, and hybrid extraction systems. By bridging gaps in waste classification, compound identification, and process optimization, this study underscores the potential of food waste as a resource for pharmaceuticals, nutraceuticals, and functional foods, aligning with circular economy goals and sustainable development.
Open Access: Yes
Conventional and Rock-Based Potassium Fertilization Improves Fennel (Foeniculum vulgare Mill.) Performance Under Extended Irrigation Intervals
Publication Name: Plants
Publication Date: 2026-02-01
Volume: 15
Issue: 4
Page Range: Unknown
Description:
Water scarcity and rising fertilizer costs challenge the sustainable cultivation of medicinal and aromatic plants in arid regions. This study evaluated the interactive effects of irrigation intervals (21, 28, and 35 days) and potassium sources (potassium sulfate and feldspar) and rates on growth, yield, essential oil productivity, and nutrient status of fennel (Foeniculum vulgare Mill.) over two consecutive seasons in Middle Egypt. Extending irrigation intervals significantly increased soil electrical conductivity while reducing soil-available potassium, whereas soil pH, organic matter, and bulk density remained unaffected. Frequent irrigation (21 days) markedly enhanced vegetative growth, yield components, seed yield, and essential oil yield, producing up to 69.7 L ha−1 oil compared with 50.5–52.0 L ha−1 under 35-day intervals. Potassium fertilization significantly improved plant performance across all irrigation regimes, with potassium sulfate at 120 kg K2 O ha−1 consistently producing the highest plant height (≈173 cm), number of umbels (≈45 plant−1), 1000-seed weight (≈13 g), seed yield, and oil yield. Potassium sulfate at 120 kg K2 O ha−1 consistently outperformed feldspar, though high-rate feldspar (572 kg K2 O ha−1) significantly improved performance over the control, indicating potential as a supplementary source. Extending irrigation to 28 days reduced water application by approximately 23% compared to 21-day intervals, with acceptable yield levels when combined with adequate potassium supply. Potassium application enhanced seed and herb N, P, and K concentrations and mitigated the adverse effects of prolonged irrigation intervals, particularly under moderate water stress (28 days). Significant irrigation × potassium interactions confirm that optimal potassium nutrition improved water-use efficiency and reproductive performance. Overall, integrating frequent or moderately extended irrigation with an adequate potassium supply—especially soluble potassium sulfate—offers an effective strategy to sustain fennel productivity and essential oil yield under water-limited conditions.
Open Access: Yes
Special Issue: Exploring Abiotic Stress in Plants—Mechanisms, Adaptations, and Mitigation Strategies
Publication Name: International Journal of Molecular Sciences
Publication Date: 2026-03-01
Volume: 27
Issue: 5
Page Range: Unknown
Description:
No description provided
Open Access: Yes
DOI: 10.3390/ijms27052182
Nitrogen Management in Crop–Soil–Environment Systems: Pathways Toward Sustainable and Climate-Resilient Agriculture
Publication Name: International Journal of Molecular Sciences
Publication Date: 2026-03-01
Volume: 27
Issue: 5
Page Range: Unknown
Description:
Abiotic stresses including drought, salinity, heat, cold, and heavy metal toxicity severely constrain plant productivity worldwide. Nitrogen (N), beyond its fundamental nutritional role, has emerged as a central regulator of plant stress responses through its involvement in metabolic reprogramming, osmotic adjustment, antioxidant defense, and hormonal signaling. This review synthesizes current advances in understanding how nitrogen availability and form influence plant tolerance to major abiotic stresses. Particular emphasis is placed on nitrogen-mediated modulation of reactive oxygen species (ROS) scavenging systems, nitrogen–carbon metabolic coordination, phytohormonal crosstalk, osmoprotectant biosynthesis, and regulation of stress-responsive gene expression. Recent molecular insights highlight the role of nitrogen transporters, nitrate signaling pathways, and nitrogen-use efficiency in stress adaptation mechanisms. Furthermore, agronomic and biotechnological strategies aimed at optimizing nitrogen management to enhance stress resilience are discussed, including precision fertilization, integrated nutrient management, and genetic approaches targeting nitrogen-responsive regulatory networks. By integrating physiological, biochemical, and molecular perspectives, this review provides a comprehensive framework for understanding nitrogen-driven mitigation strategies under abiotic stress conditions and outlines future research directions for sustainable crop production in changing environments.
Open Access: Yes
DOI: 10.3390/ijms27052477
Biorefining green triticale grass as a flavonoid-rich source of protein for sustainable food systems
Publication Name: Food Bioscience
Publication Date: 2026-05-01
Volume: 79
Issue: Unknown
Page Range: Unknown
Description:
Green biomass serves as an eco-friendly, plant-derived substitute for conventional protein sources. Leaf protein concentrate (LPC) not only acts as a viable alternative to animal-derived proteins but also contains essential vitamins and bioactive compounds providing nutraceutical advantages. The extraction technique plays a critical role in maximizing LPC yield. In this study, green juice derived from the wet pressing of green triticale biomass was divided into two aliquots, each subjected to distinct processing techniques for LPC isolation. One portion underwent direct thermal coagulation via microwave irradiation, followed by vacuum filtration, yielding green LPC (MW-GLPC) and its brown juice (GJ-BJ). The other was first centrifuged to remove large photosynthetic complexes, producing yellow juice that was subsequently thermally coagulated and vacuum filtered to obtain yellow LPC (YLPC) and its brown juice (YJ-BJ).The crude protein content in the MW-GLPC fraction (38.44 g 100 g−1 DW) was higher than the raw green juice (16.38 g 100 g−1 DW). YLPC fraction, obtained by incorporating a centrifugation step into the process, resulted in a significantly increase in crude protein (67.22 g 100 g−1 DW). For fractions of brown juice (BJ), the crude protein content differed depending on the processing technique, with GJ-BJ exhibiting 0.73 g 100 g−1 FW and YJ-BJ displaying 1.06 g 100 g−1 FW. Size exclusion chromatography (SEC) indicated that BJ primarily contained oligopeptides ranging from 200 to 3000 Da.Phytochemical assessments demonstrated that YLPC exhibits the highest concentration of some beneficial bioactive compounds, such as luteolin (27.2 μg g−1), and isovitexin (111.6 μg g−1). These findings are consistent with results obtained from the Drosophila melanogaster model under high-sugar conditions designed to simulate high-sugar-induced stress. Flies supplemented with a concentration of 20% YLPC demonstrated a 10.52% increase in viability relative to the control group, thereby indicating the beneficial potential of YLPC in high-sugar containing environments.
Open Access: Yes
Revolutionizing sugar beet yield and quality in saline sandy soil through synergistic humic acid, glauconite, and boron foliar application
Publication Name: Plant and Soil
Publication Date: 2026-01-01
Volume: Unknown
Issue: Unknown
Page Range: Unknown
Description:
Aims: Saline sandy soils severely constrain sugar beet (Beta vulgaris L.) productivity due to low nutrient retention, high salinity, and micronutrient imbalances, particularly boron deficiency. Although humic substances, glauconite, and boron fertilization have individually or pairwise improved crop performance, no previous field study has evaluated their ternary, dose-optimized integration as a multifunctional soil–plant management strategy under saline sandy conditions. Methods: This study investigated, for the first time, the combined application of soil-applied humic acid (600 kg/ha), glauconite (1100 kg/ha), and graded foliar boric acid (0, 1900, and 3800 g/ha) to test the hypothesis that their complementary physicochemical and physiological mechanisms would generate synergistic improvements in soil quality, crop performance, and sugar productivity beyond additive effects. Field experiments were conducted over two consecutive growing seasons (2021–2022) in West Minya, Egypt, using a split-plot design. Results: The integrated high-dose treatment (HG3800) significantly enhanced leaf area index (by 75%), chlorophyll content (46–71%), and net photosynthetic rate (40–128%) relative to the control. Root yield increased by 27% (reaching 56.7 ton/ha), while sugar yield rose by up to 79% (11.5 ton/ha). Sucrose concentration reached 20.4%, with reduced impurity indices and improved extractable sugar percentage (up to 90%). Based on fermentable sugar yield, the HG3800 treatment corresponded to a substantial increase in theoretical bioethanol output potential per hectare. Concurrently, soil electrical conductivity declined by 24%, soil organic matter increased, and bulk density decreased, reflecting improved soil structure and salinity mitigation. Conclusions: The ternary, dose-optimized integration of humic acid, glauconite, and foliar boron represents a novel agronomic strategy that simultaneously enhances soil physicochemical properties, physiological efficiency, and fermentable sugar production. By directly linking yield gains to increased bioethanol feedstock potential, this approach offers a scalable and multifunctional pathway for sustainable bioenergy-oriented sugar beet production in salt-affected sandy soils.
Open Access: Yes
Rapid, Matrix-Dependent Changes in Polyphenols and Antioxidant Capacity of Methanol Plant Extracts During Short-Term Storage: Implications for Analytical Timing
Publication Name: International Journal of Molecular Sciences
Publication Date: 2026-05-01
Volume: 27
Issue: 9
Page Range: Unknown
Description:
Throughout this study, the short-term stability of methanol extracts was evaluated in cases of 15 distinctive, antioxidant-rich plant materials over 3, 7, and 14 days under refrigeration (4 °C), dark room-temperature, and light-exposed room-temperature conditions. A great variability in the matrix-dependent stability of the antioxidants, as well as the pronounced impact of the implied storage conditions on their plausible degradation, was revealed and featured. Initial total polyphenol content (TPC) ranged from 50.50 ± 0.44 mg gallic acid (GAE)/g DW (rosemary) to only 0.02 ± 0.006 mg GAE/g DW (amaranth). After 14 days, pigment-rich vegetable extracts (basil, beetroot powder, spinach powder, dried onion, tomato powder, and yarrow tail) lost 86.2–89.2% of TPC and 80–99% of DPPH (2,2-diphenyl-1-picrylhydrazyl) activity across all conditions, even under refrigeration. In contrast, for Lamiaceae species, markedly higher levels of the referred parameters were to be observed after 14-day-long storage. Decrease in TPC values was found to be 43.7% (rosemary), 50.6% (thyme), and 42.9% (oregano), respectively, while DPPH values were reduced by only 17–29%. Turmeric and walnut flour showed intermediate stability. Refrigeration consistently minimized the degradation of antioxidants (e.g., rosemary’s decrease in DPPH was only 20.3% at 4 °C vs. >70% under ambient conditions), while light exposure significantly accelerated losses of antioxidants in nearly all samples. Methanol extracts of many dietary plants, particularly pigment-rich ones, exhibit rapid and pronounced changes during short-term storage. Comparison with values obtained immediately after extraction shows that even brief storage can lead to substantial deviations. Although the current sampling intervals do not capture changes within the first hours, the results clearly indicate the need to minimize delays and standardize analytical timing to avoid underestimating phenolic content and antioxidant capacity. Moreover, these findings demonstrate that measured antioxidant properties are not solely inherent to the plant material but are strongly influenced by the extract matrix and methodological conditions. Consequently, antioxidant data should be regarded as matrix- and protocol-dependent, with important implications for their interpretation, comparability, and reproducibility across studies.
Open Access: Yes
DOI: 10.3390/ijms27093723
Enhancing Water Productivity and Forage Yield of Egyptian Clover Through Subirrigation Controlled Drainage and Groundwater Utilisation
Publication Name: Agronomy
Publication Date: 2026-05-01
Volume: 16
Issue: 9
Page Range: Unknown
Description:
Water scarcity is a critical constraint to sustainable agricultural production in arid and semi-arid regions. This study evaluated the effectiveness of subirrigation controlled drainage (SCD) systems in improving water use efficiency, soil conditions, and productivity of Egyptian clover (Trifolium alexandrinum L.) over two consecutive growing seasons (2022–2024). Three drainage treatments were investigated: subirrigation controlled drainage with water table depths of 0.4 m (SCD-0.4) and 0.8 m (SCD-0.8), and conventional free drainage at 1.2 m (SFD-1.2). The results demonstrated that SCD significantly reduced irrigation water requirements, achieving water savings of up to 27% under SCD-0.4 compared with conventional drainage. The shallow water table enhanced groundwater contribution to crop evapotranspiration, reaching over 40%, which improved soil moisture availability and reduced soil water depletion. Consequently, SCD-0.4 increased fresh and dry biomass yields by approximately 18% and significantly improved water productivity and irrigation water productivity. However, controlled drainage led to increased soil salinity due to reduced leaching, particularly in upper soil layers. Economic analysis revealed that SCD-0.4 achieved the highest net returns and water use profitability. Overall, controlled drainage at shallow depths represents an effective strategy to enhance water productivity, crop yield, and economic efficiency, although long-term salinity management must be considered for sustainable implementation.
Open Access: Yes
