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Recherche d’activités biologiques dans les graines de Helianthus annuus
(2026) LARIKI Ayoub; MEZOUGH Ishak; BENYAMINA Sofiane Mourad
Sunflower seeds (Helianthus annuus L.) constitute a significant source of bioactive
compounds and enzymes of nutritional, biological, and industrial interest. This study aims to
evaluate the antioxidant activities (specifically catalase activity and DPPH scavenging) and
enzymatic activities (specifically amylase and phytase activities) of an extract prepared from
sunflower seeds. The results revealed notable antioxidant activity in the extract, evidenced by
an H2O2 degradation capacity reaching 1.22mM/mg of protein after 90s of incubation, as well
as DPPH scavenging potential with an IC50 of 0.3055mg/mL. In terms of enzymatic activity,
the extract exhibited significant amylase activity, characterized by the hydrolysis of
approximately 19.40μg of starch per mg of protein under optimal conditions of 30°C and a pH
range of 7 to 9. Phytase activity was also demonstrated through the release of inorganic
phosphorus, estimated at 0.16μg/mg of protein, with optimal activity observed at 40°C and pH
5. The amylases demonstrated greater stability across various experimental conditions, in
contrast to the phytases, which proved to be more sensitive to variations in temperature and
acidity.
Evaluation de l’effet antifongique de trois plantes médicinales -le myrte, le lentisque et la rue fétide – contre les champignons pathogènes ( Botrytis cinerea , Aspergillus niger et Penicillium expansum
(2026) MÉÇABIH Aya Anfal; MESSAOUD Marwa; AISSET Amal
Medicinal plants constitute an important source of bioactive compounds and represent a promising
alternative to chemical products used in the control of pathogenic agents.
The aim of this study was to evaluate the antifungal activity of essential oils extracted from three
medicinal plants: Myrtus communis (myrtle), Pistacia lentiscus (lentisk), and Ruta chalepensis
(fringed rue), due to their numerous biological properties and in order to propose a natural
alternative to chemical fungicides used against phytopathogenic fungi.
The extraction of essential oils from the selected plants was carried out by hydrodistillation.
Antifungal activity was evaluated using the disc diffusion method against three phytopathogenic
fungi: Aspergillus niger, Penicillium expansum, and Botrytis cinerea.
The results showed extraction yields of 0.375%, 0.17%, and 1.39% for myrtle, lentisk, and fringed
rue, respectively. They also revealed variable sensitivity of the tested fungi to the studied essential
oils, as evidenced by the largest inhibition zone produced by the essential oil of Myrtus communis
against Penicillium expansum (28 mm), followed by that of Pistacia lentiscus (15 mm), which also
exhibited interesting activity against Aspergillus niger (15 mm) and Botrytis cinerea (11 mm).
In contrast, the essential oil of Ruta chalepensis showed no inhibitory effect against Botrytis
cinerea and Aspergillus niger, while a weak activity was observed against Penicillium expansum
(7 mm).
The findings of this study indicate that the essential oils of Myrtus communis and Pistacia lentiscus
possess promising antifungal activity against the phytopathogenic fungi studied and could be
valorized as natural alternatives to chemical fungicides for the postharvest preservation of food
products.
Spatiotemporal Dynamics and Wave Propagation in the Diffusive Kermack-McKendrick Model
(2026) BAKHTI Manel Nor El Houda; BENTOUT Soufiane
We study the existence of traveling wave solutions for a diffusive Kermack–McKendrick
SIR model with standard incidence. The three compartments—susceptible S, infected I,
and recovered R—are all taken into account in the traveling waves analysis. We
demonstrate that the minimum wave speed of traveling waves for this three-dimensional
system can be obtained from the linearization around the initial disease-free equilibrium.
The proof is based on Schauder’s fixed point theorem and the Arzelà-Ascoli theorem.
This work offers a valuable approach for studying high-dimensional epidemic models.
Renforcement Parasismique Intelligent des Structures à l’Aide des Systèmes Innovants Appliqué aux Bâtiments Existants et Neufs
(2026) NACHI Manel; CHINOUNE Hadria; DERBAL Rachid; BENMANSOUR Nassima
The vulnerability of reinforced concrete structures to seismic actions represents one of the
major challenges in the field of civil engineering, particularly for buildings designed
according to outdated codes or exhibiting deficiencies in strength and stiffness. In this
context, structural strengthening techniques offer effective solutions for enhancing structural
performance and extending the service life of existing structures. Among these techniques,
Carbon Fiber Reinforced Polymer (CFRP) strengthening and concrete jacketing are widely
recognized as efficient rehabilitation methods.
This study aims to evaluate the effectiveness of these two strengthening techniques in
improving the seismic behavior of reinforced concrete elements. The influence of each
strengthening method on the mechanical and structural characteristics of the strengthened
elements is investigated through the assessment of key performance indicators, including
strength, stiffness, ductility, energy dissipation capacity, as well as the evolution of
deformations and displacements under seismic loading.
The results demonstrate that both CFRP strengthening and concrete jacketing significantly
enhance the structural performance of reinforced concrete structures. These techniques
increase load-carrying capacity, improve seismic response, and reduce the level of damage
that may occur during earthquake events. Furthermore, the study highlights that the selection
of the most appropriate strengthening technique depends on the geometric and mechanical
characteristics of the structure, its level of deterioration, and the objectives of the
rehabilitation program.
The findings confirm the importance of modern strengthening techniques as effective and
economical solutions for improving the safety of existing structures, reducing their seismic
vulnerability, and ensuring their long-term durability and performance.
Approche ethnobotanique des plantes médicinales employées contre les mycoses cutanées et l’eczéma dans la région d’Ain Témouchent
(2026) METTRI Jawida; SEGHIR Sadia; BENDJEDOU Houaria
Medicinal plants play an important role in the traditional therapeutic practices of the
population of the Ain Témouchent wilaya, particularly in the treatment of skin fungal
infections and eczema. In this context, an ethnobotanical survey was conducted using 82
questionnaires distributed across three regions of the wilaya to identify the plant species used
and their methods of use. The results identified 43 plant species belonging to 28 botanical
families, dominated primarily by the Asteraceae (19%), Lamiaceae (16%), and Fabaceae
(9%). The most frequently cited species were Marrubium fontianum (FC = 17%, RFC = 0.21),
Matricaria chamomilla (FC = 15%, RFC = 0.19), and Urtica dioica (FC = 13%, RFC = 0.16).
Leaves were the most commonly used plant part; decoction was the primary method of
preparation; and massage was the most frequent route of administration. The
sociodemographic analysis showed that people over 50 years of age mostly women, 79% of
whom were married and living in rural areas were the primary users of medicinal plants and
preferred traditional medicine. Furthermore, 70.7% of respondents reported using these
plants, and 70% believed they did not pose any significant toxicity. These results highlight the
richness of the ethnobotanical heritage of the wilaya of Aïn Témouchent and underscore the
importance of preserving and promoting traditional knowledge regarding the use of medicinal
plants.