http://dspace.univ-setif.dz:8888/jspui/handle/123456789/51 Wed, 12 Aug 2026 15:43:31 GMT 2026-08-12T15:43:31Z http://dspace.univ-setif.dz:8888/jspui/handle/123456789/6703 Titre: Food Microbiology : Courses Intended for Third-Year Bachelor's (Licence) Students Auteur(s): BAKLI, Sabrina Résumé: This textbook is primarily intended for third-year undergraduate students in Microbiology. It has been developed in accordance with the official curriculum for the Food Microbiology module and is designed to serve as a comprehensive teaching and learning resource. It may also be beneficial to students in related disciplines, including biotechnology, food science, nutrition and quality control. The textbook introduces the fundamental principles of food microbiology, with particular emphasis on the interactions between microorganisms and food. It covers the major foodborne microorganisms of public health importance, including pathogens responsible for food intoxications, foodborne infections, and foodborne toxicoinfections. It also examines the molecular mechanisms underlying microbial pathogenicity and virulence. In addition, the textbook addresses the principal sources of food contamination, the intrinsic and extrinsic factors influencing microbial growth and survival in food, and the fundamental principles of food hygiene, prevention, and microbiological control required to ensure food quality and safety. Prepared in accordance with the official curriculum established by the Ministry of Higher Education and Scientific Research, this textbook has been designed to provide students with a clear, well-structured, and scientifically rigorous learning resource. Its primary objective is to facilitate the acquisition of fundamental knowledge in food microbiology while fostering a comprehensive understanding of the microbiological hazards associated with food, as well as the strategies used for their prevention, detection, and control. Ultimately, this textbook is intended to serve as a valuable academic reference, providing students with the essential scientific foundation required for advanced studies and future professional practice in the fields of food microbiology, food safety, and quality Thu, 01 Jan 2026 00:00:00 GMT http://dspace.univ-setif.dz:8888/jspui/handle/123456789/6703 2026-01-01T00:00:00Z http://dspace.univ-setif.dz:8888/jspui/handle/123456789/6643 Titre: Activités antimicrobienne et antioxydante des extraits de Ruta chalepensis L. Auteur(s): Selloum, Mounir Résumé: The aim of this study is to determine the chemical composition, phenolic content, as well as the antibacterial, antifungal and antioxidant activities of hydromethanolic extracts from R. chalepensis collected at three different periods: before flowering (BF), during flowering (DF) and after flowering (AF). Three hydromethanolic extracts were prepared: the before flowering extract (BFE), during flowering extract (DFE) and after flowering extract (AFE). Hydromethanolic extracts analysis was conducted regarding their chemical composition by HPLC-DAD-ESI/MS method, quercetin, graveolin, bergapten, isoimperatorin, chalepin, rutamarin and β-carotene were detected. Also, total phenolics and flavonoids contents were determined. The AFE displayed the maximum polyphenol and flavonoid levels; 84.54 ± 1.66 µg GAE/mg dry extract and 25.15 ± 0.88 µg QE/mg dry extract, respectively. Antibacterial activity was evaluated against seven bacterial strains using disc diffusion (DD) method and minimal inhibitory concentration (MIC). The results of the studied plant showed an important antibacterial activity against both Gram-negative and Gram-positive bacteria. The bacterial strains showed sensitivity ranging from moderate to high, either in terms of ID (08.67 to 17.67 mm) or in terms of MIC (01.95 and 31.25 mg/ml). These extracts also exhibited excellent activity against eight filamentous fungi growth when tested by incorporation of plant extracts into the culture medium method at (10%) reduced the growth from 25 % to 97% of all fungi. On the other hand, The antioxidant activity was assessed using four methods; DPPH ,with IC50 ranging between 14.18 ± 1.02 and 30.96 ± 1.80 μg/mL, β-carotene/linoleic acid, with IC50 ranging between 34,86 ± 0,78 and 49,06 ± 0,15 μg/ml and reducing power, with EC50 varied between 100,61± 1,25 and 139,99± 2,08 µg/ml and TAC, with values ranging between 125,12 ± 2,47 and 160.59 ± 5.78 µg AAE/mg extract. In conclusion, the results revealed that R. chalepensis hydromethanolic extracts have strong antibacterial and antioxidant properties, highlighting their potential as natural sources for developing novel antibacterial and antioxidant agents. Thu, 01 Jan 2026 00:00:00 GMT http://dspace.univ-setif.dz:8888/jspui/handle/123456789/6643 2026-01-01T00:00:00Z http://dspace.univ-setif.dz:8888/jspui/handle/123456789/6596 Titre: IMMUNOLOGY : Course intended for L2 Biology Auteur(s): KHITHER, Hanane Résumé: Immunology is the branch of biology that studies the functioning of the immune system in both physiological and pathological contexts. It enables the investigation of the properties of immune effectors and their targets both in vivo and in vitro. The immune system comprises organs, tissues, cells (such as T and B lymphocytes, macro- phages, and leukocytes), and molecules (including antibodies and interleukins) that partici- pate in immunity. Lymphoid organs and tissues are distributed throughout the body. Immune cells circulate within and between these organs via blood and lymph. They communicate either through direct contact (receptor–ligand interactions) or at a distance via secreted molecules (media- tor–receptor interactions). These soluble, secreted molecules are called cytokines substances produced by certain immune cells that act on other immune cells to regulate their activity. This general term encompasses lymphokines, monokines, chemokines, and interleukins. Wed, 01 Jan 2025 00:00:00 GMT http://dspace.univ-setif.dz:8888/jspui/handle/123456789/6596 2025-01-01T00:00:00Z http://dspace.univ-setif.dz:8888/jspui/handle/123456789/6564 Titre: Application of bioactive compounds in food bio-preservation and infection protection Auteur(s): Gharzouli, Merihane Résumé: Fungal contamination of citrus crops represents a significant issue in Algeria. The primary aim of this study is to limit fungal growth on orange fruits using the nanoemulsions obtained from plants of Origanum majorana, Citrus limon, Cymbopogon citratus and Foeniculum vulgare. The essential oils from these plants were extracted using hydrodistillation method, and their nanoemulsions were produced using ultrasonication method. The chemical composition was analyzed using a GC-MS system, and the physicochemical properties of the nanoemulsions were assessed. The antimicrobial efficacy was evaluated in vitro. Furthermore, the antifungal potential of marjoram and fennel was assessed in silico. The GC-MS analysis demonstrated that the nanoemulsification increases the concentrations of terpinen-4-ol and cis-β-terpineol in marjoram, as well as estragole and anethole in fennel, in addition to neral and geranial in both lemon and lemongrass oils, while reducing the levels of α-terpinene, fenchone, limonene, γ-terpinene, and β-myrcene. The nanoparticles exhibited a narrow particle size distribution, indicating high stability and monodispersity of the nanoemulsions. The TEM imaging of the nanoemulsions showed a spherical morphology with diverse nanometer-scale dimensions. The molecular and the phylogenetic analysis of the isolated fungi from orange fruits showed 100% homology to P. expansum and P. digitatum. the essential oils exhibited greater potency compared to their nanoemulsions, with MIC values spanning from 2% to 0.12% against bacteria and from 1% to 0.03% against fungus. Furthermore, the majority of the tested fungi were completely inhibited by lemongrass. On the other hand, F. vulgare showed the weakest antimicrobial activity. Strong binding-free energy values were observed in the interactions between essential oil or nanoemulsions and fungal enzymes, with notable docking scores (−6.6 to −7.0 kcal/mol) for aromatic components. The application of nanoemulsified marjoram, lemon and lemongrass as a coating on orange fruits significantly inhibit the growth of P. expansum and P. digitatum molds compared to uncoated samples. The use of nanoemulsions minimize negative changes in quality parameters of orange fruits throughout storage, encompassing titratable acidity (TA), pH, total soluble solids (TSS), ascorbic acid concentration, weight loss and firmness. The nanoemulsified O. majorana and C. limon did not influence the sensory attributes of the coated fruits as compared to the C. citratus nanoemulsion. Overall, the tested nanoemulsions demonstrated their high efficacy in managing pathogens affecting orange fruits. Wed, 01 Jan 2025 00:00:00 GMT http://dspace.univ-setif.dz:8888/jspui/handle/123456789/6564 2025-01-01T00:00:00Z