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Histopathological and pathomorphological effects of 15 ppb mercuric chloride on Persian sturgeon, Acipenser persicus, were investigated using histological and electron microscopy observations. Light microscopy showed that the gill epithelial hypertrophy, wrinkling and hyperplasia in lamellar epithelia and lamellae fusion occurred after 48 h of exposure. Gill epithelia also showed occasional necrosis, which had almost been completed and blood emerged from the capillaries. However, occasional necrosis in some regions of the filament, both with blood emerging and with no bleeding, was observed by using electron microscopy. These injuries were well observed in inter-lamellar regions of the filament and also wrinkling of the lamellar epithelium. Ultrastructural observations showed some cellular disorders in gill epithelium of the Persian sturgeon, A. persicus, fry. In addition, increase in apical vesicles of the chloride cells and necrosis in apical surfaces of some chloride cells, hypertrophy and necrosis of the chloride cells’ mitochondrion and endoplasmic reticulum also were some of the other cellular disorders observed through transmission electron microscopy. In conclusion, the gills of A. persicus fry were sensitive to low concentrations of inorganic mercury (HgCl2).

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The gill Structure and localization of Na⁺, K⁺-ATPase were examined through branchial arches of the Persian sturgeon, Acipenser persicus larvae (25 days-post-hatched, 417.3 mg). Studies were conducted through light microscopy (H&E Staining) and immunofluorescence for Na⁺, K⁺-ATPase. Results showed each gill consisted of four complete holobranches and opercular hemibranch. Each filament carried rows of lamellae consisting of a network of interconnecting blood lacunae, which were lined by pillar cell flanges. Pavement cells covered the outermost layer of the lamella and blood cells were found in lacunae. High density of ionocytes (529.73 per mm² of the gill tissue) was found at the base of the lamella, in the interlamellar regions, on the filaments and the septums. Ionocytes possessed large size and round basal nuclei. Ionocytes possessed strong immunofleurescence in their cytoplasm, especially in the basolateral sides because of high concentration of the enzyme. The results showed that the main structures of the gill has already been formed at this developmental stage of the Persian sturgeon, and along with its respiratory and excretory roles, it also plays an important role in osmoregulation.

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Background: This study was performed to determine antifungal activity of silver nanoparticles (nano-Ag) compared to voriconazole on clinical and standard strains of Aspergillus fumigatus.
Materials and Methods: Inhibitory potency of nano-Ag was determined using microtiter broth dilution method. Susceptibility tests were performed against A. fumigatus isolated from BAL (bronchoalveolar lavage) of patients who suffered from respiratory problems and compared with the strain (ATCC: 204305) by broth dilution antifungal susceptibility test of filamentous fungi approved by the Clinical and Laboratory Standards Institute M38-A. In addition, cytotoxicity effect of silver nanoparticles was studied on epithelial cell line by MTT assay.
Results: From 60 BAL samples the following strains were isolated; A. flavus (n=21), A. niger (n=3), and A. fumigatus (n=1). The minimum inhibitory concentration (MIC₉₀) values of nano-Ag were 0.25 and 0.5 μg.mL^-1 for standard strain and clinical isolates respectively. The  Minimum Fungicidal Concentration (MFC) values of nano-Ag were 0.5 and 1 μg.mL^-1for standard strain and clinical isolates respectively. MIC90 values of voriconazole were 0.125 and 0.25 μg.mL^-1 for standard strain and clinical isolate respectively. The MFC values of voriconazole were 0.25 and 0 μg.mL^-1 for standard strain and clinical isolates respectively. Silver nanoparticles exhibited low cytotoxicity in 0.25 μg.mL^-1 concentration.
Conclusion: Our results showed high antifungal activity of silver nanoparticles against Aspergillus isolates. Furthermore, the availability of a wide form of nano-Ag structures can be considered as novel agents to decrease fungal burden in medical application.

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The probiotic effects of Saccharomyces cerevisiae and Aspergillus niger on the feeding efficiency, body composition, ammonia excretion, blood serum enzymes and the intestinal microbiota of juvenile beluga, Huso huso was investigated. The fish (31.8±2.81g) were randomly allocated into 12 oval tanks at a density of 30 individuals per tank with three replicates for each treatment,. The fish were fed either a basal diet (as control) or the diet supplemented with S. cerevisiae and A. niger (2×10⁶, 4×10⁶ and 6×10⁶ cells g^-1) for 8 weeks. The results indicated that the probiotic supplemented diet at 6×10⁶ (cells g^-1) significantly improved FCR and other nutritional indicators compared to the control treatment (p<0.05). Significant improvements (p<0.05) were also observed in ammonia excretion and blood serum enzymes between treatments. Total viable fungus and Lactobacillus spp. count were significantly improved in treatment compared to control (p<0.05). These results indicated that S. cerevisiae and A. niger improved feeding performance and blood serum enzymes of beluga.

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The effects of pyrene on gill, liver and kidney of common carp (Cyprinus carpio) were examined by exposing 30 fish (140 ±10 g to pyrene at sublethal concentrations of 10, 50 and 100 µg/l for 35 days. Samples were taken from the organs and fixed in bouin fixative; then, dehydrated, cleared, parafinated and cut by microtome according to the standard method. Afterwards, all sections were studied by light microscope. In gill tissue, lamella hyperemia, hyperplasia, S shaped, and clubbing were observed, while lamella fusion and necrosis were observed in higher concentration of pyrene. Hepatocytes vacculation, congestion of sinusoids, macrophages loaded with hemosiderin were seen in the liver, while in higher concentrations of pyrene, picnotic and kariolized nuclei, and tissue necrosis were seen. Tubule casts, hyperemia, degenerating tubules were seen in kidney exposed to lower concentrations of pyrene, while hemosiderin-laden macrophages, degenerating tubules with greater intensity as well as necrosis was observed in higher concentrations. The results indicated that pyrene may have negative effects on homeostasis, fish health and vital organs in short time exposure due to histological changes, while it could have greater impacts in long term exposure and higher concentrations.

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Background: Aspergillosis is an opportunistic infection caused by Aspergillus spp in immunocompromised patients. The role of HSP90 in Aspergillus drug resistance is still unknown. The aim of this study was to evaluate the correlation between the presence of HSP90 gene and polyene resistance in Aspergillus spp using PCR.
Materials and Methods: In this study, 32 Aspergillus strains were used, which were isolated from patients susceptible to aspergillosis through Bronchoalveolar lavage (BAL) and identified by conventional methods. The isolates were cultured on Sabouraud dextrose agar (SDA). Susceptibility testing against amphotericin B was conducted according CLSI standards (M38-A). Also, the presence of HSP90 gene was evaluated using PCR.
Results: Of 32 Aspergillus strains used in this study, 16 (50%) isolates were identified as A. Flavus, 12 (37.5%) isolates as A. fumigatus, and 4 (12.5%) isolates as A. terreus. Among these species, 19 (59.37%) isolates were sensitive to amphotericin B whereas 13 (40.62%) were resistant. Moreover, there was a significant difference  between the presence of HSP90 gene and resistance to amphotericin B in Aspergillus species.

Conclusions: The presence of HSP90 gene provides evidence that shows this gene may play important role in resistance to amphotericin B in Aspergillus isolates. Although numerous regulatory genes are involved in resistance mechanisms, they remaines to be more clarified

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Protein compounds were extracted from the mucus of sea anemone, Stichodactyla haddoni, and their effects on the gills of rainbow trout, Oncorhynchus mykisswere examined. Sea anemone samples were collected from the intertidal zone of the eastern coast of Hormuz Islandand frozen samples were transported to the laboratory. Then the mucus was extracted using of the PBS solvent and doses of 5, 10 and 24 mg/dry weight of total protein was injected into the tail vein of the fish. Upon the inactivation of fish, histopathological changes were examined using of the classical histological method. Lethal signs were observed in the gills, including aneurysm, hypertrophy of epithelial cells, lamella clubbing and deformation, subepithelial edema, lamella congestion in the interlamellar region and necrosis. The damages were more serious with increasing doses. The results showed that protein compositions of the mucus can cause numerous lesions in the gill tissue of fish, which act as an excretory, respiratory and ionic regulation tissue, the failure of which can lead to failure of fish’s vital functions that can be one of the reasons for the death of the hunted fish.  The results showed that the protein compositions of mucus can cause numerous lesions in the gill tissue, as an excretory, respiratory and ionic regulation tissue lead to failure of it functions that itself can be one of the reasons hunted fish death.

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 The chronic effects of Neem Azal on growth parameters, survival and gill morphology of common carp (Cyprinus carpio) with average weight of 10.56 ± 0.12 g were determined. A total of 120 fish were distributed equally between three treatments and a control group, with three replicates each. To determine the chronic effect, sublethal concentration of poison, 0.12 (10% LC₅₀), 0.24 (20% LC₅₀), 0.36 ppm (30% LC₅₀), was selected and fish were exposed to these doses for 28 days. Increasing doses of Neem Azal had a significant effect on growth parameters, as the growth declined significantly when poison dose increased (P<0.05). There were no significant differences in survival (P>0.05. Reactions such as irregular swimming, abnormal behavior, nervous reaction to external stimulator, increased opercular beating ​​and anorexia were observed during the test. Damage to the gill tissue also increased as the poison levels increased. Generally, the negative effects of Neem Azal on growth parameters and gill morphology of common carp were observed as biopestiside levels increased. 

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By conducting three different methods, we report on the isolation of five novel strains of non-symbiotic bacteria from crushed infective juveniles (IJs) of four species of entomopathogenic nematodes (EPN) including Heterorhabditis bacteriophora, Steinernema carpocapsae, Steinernema feltiae, and Steinernema glaseri and five bacterial species from hemolymph of insect larvae infected with EPNs. Samples of hemolymph of infected Galleria mellonella L. larvae by EPNs and crushed surface sterilized IJs were bulk streaked onto both MacConkey and NBTA agar. To further ensure diagnoses, extracted DNA from IJs bulk was subjected to PCR by 16S-rRNA bacterial universal primers. Bacteria were identified using biochemical and phylogenetic analysis. Based on 16S-rRNA gene sequence, maximum parsimony, maximum likelihood and neighbour joining phylogenetic analyses were conducted, as well as comparisons of predicted RNA secondary structures. Four species of bacteria were identified including: Stenotrophomonas maltophilia strain IR11 from S. feltiae; S. pavanii strain IR20 from S. glaseri; Acinetobacter junii strain IR8 from S. carpocapsae; and Alcaligenes faecalis strains IR1 & IR15 from S. feltiae and H. bacteriophora respectively as non-symbiotic bacteria from IJs and five species probably originated from G. mellonella intestine including Citrobacter gillenii isolate S3, Enterobacter asburiae isolate S4, Klebsiella oxytoca isolate S5, Morganella morganii isolate S6 and Serratia marcescens isolate S6.

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Common carp is infected by five Dactylogyrus spp in both pond and natural lake habi-tats in Iran, namely D. extensus D. anchoratus, D. achmerovi, D. vastator and D. sahuensis. Fry and fingerlings are more sensitive to infection and their sensitivity is increased with the higher density of fishes usually found in ponds. General gill lesions in dactylogyrosis are quite similar but there are few differences in local lesions among Dactylogyrus spp infecting common carp. In this paper, the geographical distribution of Dactylogyrus spp of common carp is presented and the gill histopathology caused by D. sahuensis is described and discussed.

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Chitin and chitosan are two very important biopolymer products that have so many usages in the high cost industries. Chitin Converts into chitosan via de-acetylation of chitin. It occurs by alkaline melting method in the absence of oxygen. Chemical structure change, severe environmental pollution and De-polymerization are of the major problems in producing high quality chitosan. In this study for conversion of chitin into chitosan fungus Aspergillus niger strains (ATHUM-10864), the generator of de-acetylases enzymes were used instead of chemicals. Chitosan quality was determined via elemental analysis infrared spectroscopy, X-ray tomography, molecular weight determination and estimation of crystallinity percent, color and molecular structure.The results showed 80±5% efficiency in the conversion of chitin into chitosan or de-acetylation degree of chitin. The gained chitosan contained of 44.4 % carbon, 8.9 % nitrogen, 2.7 % hydrogen and 39.5 % oxygen. The physical characteristics were as 94.5% Crystallinity and pale brown color. The chemical structure of per unit of chitosan was obtained as C6H12NO4. The results showed that replacing biological methods instead of chemicals was possible to access well quality products. It also eliminates the use of chemical materials such as concentrate sodium hydroxide that is damaging the environment.

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Research subject: Aspergillus niger stands as a versatile filamentous fungus renowned for its industrial significance in producing various organic acids, notably citric acid and oxalic acid. Low sugar concentration as substrate leads to the production of oxalic acid, therefore, this article delves into the intricate metabolic machinery orchestrating the synthesis of these acids within A. niger, shedding light on the pivotal role of culture media composition and metabolic activity.
Research approach: Through a comprehensive review of A. niger metabolism, this study elucidates the pathways involved in the biosynthesis of citric acid and oxalic acid, unraveling the intricate interplay of enzymatic cascades and regulatory mechanisms governing their production. Furthermore, it explores the impact of small molecules on metabolic flux through regulatory media, offering insights into strategies for controlling metabolic flux in order to eliminate oxalic acid production and amplify the citric acid production considering low sugar content of 30 g/l.
Main results: After careful review of previous researches, key reactions and genes was found and introduced for future researches in order to control the A. niger products. Examination of small molecule as a regulator in culture media not only elucidated the importance of culture media composition but also employing them helped us to redirect flux from oxalate toward citrate. NH₄, Leucine, Cysteine, NaF, Glutathione, and Metformin were all found to be effective in the elimination of oxalic acid. In this regard, employing them leads to the production of 1868, 1530, 2093, 2250, 787, and 675 mg/L oxalic acid in comparison to the control culture media in which 5560 mg/L oxalic was produced. In addition, elimination of oxalic acid in some cases leads to the production of more acids like the culture containing NH₄, Cysteine and Metformin.

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Backgrounds: Aspergillus fumigatus is a pathogen responsible for invasive aspergillosis and the main leading cause of death in immunosuppressed individuals. The present study aimed to evaluate the impact of eugenol-loaded chitosan nanoparticles on the expression of CYP51a and CYP51b, two well-known genes responsible for triazole drug resistance in A. fumigatus.
Materials & Methods: The minimum inhibitory concentration (MIC) of eugenol-loaded chitosan nanoparticles, chitosan, eugenol, and itraconazole was determined based on the Clinical and Laboratory Standards Institute M38-E3 method at concentrations of 4.6-2400, 11.7-12000, 2-2048, and 1-256 μg/mL, respectively. The expression of CYP51A and CYP51B was evaluated in A. fumigatus exposed to 0.5, 1, and 2× of MIC concentration of NPs and itraconazole using the real-time polymerase chain reaction.
Findings: The obtained results showed that eugenol-loaded chitosan nanoparticles sucessfully reduced A. fumigatus fungal growth at 300 μg/mL concentration. MIC of chitosan, eugenol, and itraconazole was measured to be 6000, 256, and 4 μg/mL, respectively. The results of real-time PCR also revealed that eugenol-loaded chitosan nanoparticles increased the expression of both CYP51A and CYP51B in a dose-dependent manner. The expression of fungal CYP51A and CYP51B at mRNA level was significantly increased 1.26, 1.93, and 3.1-fold as well as 1.2, 2.1, and 2.4-fold at concentrations of 150, 300, and 600 μg/mL, respectively (p<.05). However, it seems that the prepared nanoparticles had a lower impact on the expression of these genes compared to itraconazole.
Conclusion: Overall, these findings suggest that the treatment of A. fumigatus with eugenol-chitosan nanoparticles could increase the expression of the CYP51 gene, suggesting the anti-fungal property of these nanoparticles.

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Backgrounds: Allium cepa L. as a traditional medicine is a rich source of beneficial bioactive metabolites. In the present study, the effect of A. cepa ethanolic extract (EAC) was studied on Aspergillus fumigatus growth, ergosterol synthesis, gliotoxin production, and gliP gene expression.
Materials & Methods: The minimum inhibitory concentration (MIC) of EAC (125-4000 µg/mL) was determined against A. fumigatus isolates according to Clinical and Laboratory Standards Institute (CLSI) guidelines (M-38). Protease activity, gliotoxin production, cell membrane ergosterol content, ultrastructure, and gliP gene expression were evaluated in the fungus exposed to 0.5× MIC concentrations of EAC (1000 μg/mL) and fluconazole (FCZ: 64 μg/mL).
Findings: Ergosterol content was significantly reduced to 0.53 and 0.45 µg/mg in FCZ- and EAC-treated fungal cells, respectively (p< .001). The protease activity was significantly inhibited in both EAC- and FCZ-treated groups. The gliotoxin production was inhibited by 51.55 and 68.75% in the treated groups with FCZ and EAC, respectively. The expression of gliP in both EAC- and FCZ-treated A. fumigatus groups was significantly reduced by 0.40 and 0.53-fold, respectively (p< .05).
Conclusion: This study finding revealed that A. cepa ethanolic extract (EAC) effectively suppressed the growth and virulence factors of A. fumigatus, which could be attributed in part to its bioactive metabolites. Further studies are recommended to isolate and identify these metabolites as potential candidates for the development of antifungal drugs.

 

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Antimicrobial packaging is a form of active packaging that could extend the shelf-life of foods and provides microbial safety for consumers. In order to control undesirable microorganisms on food surfaces, volatile and non-volatile antimicrobial agents can be incorporated into polymers. Incorporation of essential oils and other antifungal agents in edible films composition is an antimicrobial packaging that able to inhibit fungal growth on the pistachio and aflatoxins production. The antifungal activity of Sage (Salvia officinalis) extracts against Aspergillus flavus in whey protein concentrate-based coating on pistachio kernels was investigated. The antifungal effect of Sage extracts was investigated in culture media by direct method (well method) and application of whey protein concentrate (WPC) films as discs (disc method) incorporated with different concentrations of extracts. In order to evaluate the antifungal effect of extract in pistachio, kernels coated with different concentrations of extract inoculated with a culture media discs contain 9-day-old growing A. flavus colony and the growth rate of inoculated discs were measured during 1 week. In experimental condition, minimal inhibition concentration was achieved by 155 ppm of ahcoholic extract (30 percent concentration). The results also showed that WPC coating incorporated with 4000 ppm of Salvia officinalis extracts on pistachio kernels inhibited A. flavus growth totally. Paying regard to economical aspects of importance of contamination with toxigenic fungi in pistachio kernel suggest the application of Sage extract incorporated in edible coatings for toxigenic fungi growth and toxin production in foods.   

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 Aspergillus flavus is one of the important species of molds that can produce toxins during improper storage of wheat grains. In this study, different amounts of calcium oxide (0, 0.5, and 1%) were mixed with wheat samples containing mold spores. After 20 days, the samples were exposed to gamma radiation (0, 5, 10, 15, and 20 KGy). The presence of A. flavus, Aflatoxin B₁ (AFB₁), aflatoxin B₂ (AFB₂), aflatoxin G₁ (AFG₁), and aflatoxin G₂ (AFG₂) was assessed in samples. The results indicated that the effects of calcium oxide, gamma irradiation, and their interactions were significant on A. flavus, AFB₁, and AFB₂ contamination. Furthermore, other toxins like AFG₁ and AFG₂ were not found in the samples. An additional reduction in AFB₁ and AFB₂ was observed when irradiation was accompanied by Cao, and the maximum inhibition of aflatoxin production was achieved at 0.5% CaO. Consequently, based on the standard maximum limit of 10 KGy for cereals, the findings of this research suggest that 0.5% of calcium oxide and 10 KGy of irradiation could be applied in the storage of wheat grains to mitigate A. flavus, AFB₁, and AFB₂.

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The black pod disease of cocoa in Ghana caused by Phytophthora palmivora and P. megakarya is traditionally managed with fungicides. Because of challenges associated with fungicide use, biological control options, if available, are worth trying. A fungus with proven usefulness in suppressing P. palmivora and P. megakarya in dual plate cultures and cocoa pods has partly been identified as an Aspergillus (designated AI_1). However, its exact identity has been unknown, requiring specific identification by comparing it with known Aspergillus flavus strains (designated AI_2, AI_3, AI_4, and AI_5). It was retested against P. palmivora to confirm the potency of AI_1. The putative A. flavus isolates were also tested for the first time against P. palmivora. Morphological features were determined on carrot agar (CA), potato dextrose agar (PDA), and malt extract agar (MEA). Genomic DNAs from the Aspergillus isolates were subjected to the ITS region and β-tubulin gene sequencing. All the Aspergillus isolates inhibited P. palmivora in assay plates by levels ranging from 89.33 to 95.33% (Experiment 1) and 46.67 to 60.33% (Experiment 2). Generally, the AI_1 produced culture features similar to those of the putative Aspergillus flavus isolates. ITS region sequence analysis grouped all isolates as A. flavus and beta-tubulin also grouped AI_1, AI_2, AI_3, and AI_4 as A. flavus but differentiated AI_5 as A. flavus var. parvisclerotigenus. AI_3 recorded the highest inhibition zone and prevented black pod development of inoculated pods as well. The previously unknown Aspergillus isolates AI_1 is now conclusively identified as A. flavus.

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Background: The present investigation aimed to survey the in-vitro inhibitory effects of nitroglycerin against Candida albicans, Trichophyton rubrum, and Aspergillus flavus.
Materials & Methods: In the current investigation, 99 fungal isolates were gathered from patients referred to the Medical Mycology Laboratory of Tehran University of Medical Sciences. The disk diffusion method was done based on Clinical and Laboratory Standards Institute (CLSI) M44-S2 guidelines. Also, the microdilution method was performed base on CLSI guidelines for filamentous fungi (document M38-A2) and yeasts (document M27-A3).
Findings: In the disk diffusion method, all isolates of C. albicans (n=33, 100%) and A. flavus (n=33, 100%) showed sensitivity to nitroglycerin, whereas all isolates of T. rubrum (n=33, 100%) showed resistance to nitroglycerin. On the other hand, in the microdilution method, the minimum inhibitory concentration (MIC) of nitroglycerin against C. albicans and A. flavus isolates was 0.5 mg/mL, whereas the MIC of nitroglycerin against T. rubrum was 0.12 mg/mL.
The results showed that the MIC of nitroglycerin against dermatophytes was about one-quarter of its MIC against C. albicans and A. flavus, and this difference was statistically significant (p< .05).
Conclusion: Considering the potential and efficacy of nitroglycerin against yeasts and filamentous fungi (saprophytes and dermatophytes), complementary in-vivo and in-vitro studies should be done.

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Intercultural competence plays a significant role in learning French language because language and culture are correlative like the two sides of the same coin. In other words, learning a language is not merely concerned with learning its structure and vocabulary, yet in order to communicate, the language learner should study the culture of the target country well and respect it. Thus, teaching culture in the process of learning French language seems to be a crucial task.
French literature is considered one of the richest resources that one can use to get familiar with French culture and the instructors can teach the culture to language learners, using some literary texts in their classes. Teaching a language with the help of literature is not merely intended for higher-level classes but one may take advantage of literary texts to teach the introduction to culture in lower-level classes. In this article, the authors attempt to introduce thirteen cultural elements of Gililian Lazar's theory after examining the impact of cultural education through literary texts and apply them in three literary texts in The French Literature Progressive (Littérature Progressive du Français); beginner-level literary texts also contain cultural elements and can help the teacher to teach culture. Then, some assignments are proposed to present the points in the class. These activities include personalization, providing explanations, asking students to infer cultural information, making cultural comparisons, making association, providing cultural background information as reading or listening comprehension and extention activities. In fact, doing these exercises improves individual and social capacities.
Our objective in this study is to transform the course of French literature at the beginner level to develop the linguistic and individual capacities of the students and allow them to better understand themselves through other cognitions. To reach this goal, the question will be answered: How does literature improve intercultural competence? And finally, we recommend French language instructors include literary texts in the process of teaching and stimulate students’ curiosity to know cultural issues.