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The use of synthetic food additive and the appearance of antibiotic resistance are at the basis of important human health problems. The substitution of synthetic compounds with new natural substances extracted from plants or microorganisms is therefore the ideal solution to this scourge. The objective of this work was to evaluate the phyto-constituents (polyphenols, flavonoids and condensed tannins), and to test the biological activities (antioxidant, antibacterial and antiviral) of the Ajuga iva (L) aerial part extracts. The antioxidant activity assayed by DPPH method showed an IC 50 of 0.43 ± 0.03 mg/mL. Antibacterial activity of aqueous and hydro methalonic extracts was tested against seven pathogenic bacteria (Staphylococcus aureus, Methicillin Resistant Staphylococcus aureus (MRS), Listeria monocytogenes, Pseudomonas aeruginosa, Bacillus cereus, Escherichia coli and Salmonella enteritidis) using the diffusion method. A Thin Layer Chromatography-bioautotography-guided was performed, and the isolated antibacterial fraction was identified by CG-MS analysis. Antiviral effect of methanolic extract performed on 4 viruses: Coxsackie Virus type B-3 (CVB-3), Adenovirus type 5 (ADV-5), Respiratory Syncytial Virus type B (RSV-B) and Herpes Simplex Virus type 2 (HSV-2) showed an activity against Coxsackie Virus. As a result of this study, the aerial parts of Ajuga iva (L) extract could be used in the food, cosmetic, medical and health sectors., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

The present work was developed to evaluate the in vitro antioxidant, antibacterial, antileishmanial and cytotoxic activities of Echium arenarium (Guss) extracts, and to analyze their phytochemical composition. The highest content of total phenolic compounds was obtained in the ethyl acetate extract which showed the best DPPH scavenging activity and β-carotene bleaching inhibition (IC 50  = 1.1 and 9.94 μg/mL respectively). It also exhibited the highest antibacterial activity against Gram-positive bacteria (L. monocytogenes; S. aureus; MRSA, E. faecalis and B. cereus) and antileishmanial activity against L. major (IC 50  = 13.91 ± 0.43 μg/mL) and L. infantum (IC 50  = 9.91 ± 0.15 μg/mL). Moreover, the active extract exhibited potent antiamastigote activity (IC50 = 22.48 ± 0.14 μg/mL and 18.59 ± 0.09 μg/mL against L. major and L. infantum respectively). Cytotoxicity studies revealed low toxicity against Raw 264.7 macrophage cell line (IC50 = 145.80 ± 0.84 μg/mL, SI < 10). Luteolin-7-O-glucoside was identified as the major flavonoid component by RP-HPLC analysis. In conclusion, Echium arenarium (Guss) extract was characterized by a wide range of biological activities and could be used as a potential natural anti-infectious drug., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Background: Cryptosporidiosis represents a major public health problem. This infection, caused by a protozoan parasite of the genus Cryptosporidium, has been reported worldwide as a frequent cause of diarrhoea. In the immunocompetent host, the typical watery diarrhea can be self-limiting. However, it is severe and chronic, in the immunocompromised host and may cause death. Cryptosporidium spp. are coccidians, which complete their life cycle in both humans and animals. The two species C. hominis and C. parvum are the major cause of human infection. Compared to studies on C. hominis and C. parvum, only a few studies have developed methods to identify C. meleagridis., Aim: To develop a new real time PCR-coupled High resolution melting assay allowing the detection for C. meleagridis, in addition of the other dominant species (C. hominis and C. parvum)., Methods: The polymorphic sequence on the dihydrofolate reductase gene (DHFR) of three species was sequenced to design primers pair and establish a sensitive real-time PCR coupled to a high-resolution melting-curve (HRM) analysis method, allowing the detection of Cryptosporidium sp. and discrimination between three prevalent species in Tunisia. We analyzed a collection of 42 archived human isolates of the three studied species., Results: Real-time PCR coupled to HRM assay allowed detection of Cryptosporidium, using the new designed primers, and basing on melting profile, we can distinguish C. meleagridis species in addition to C. parvum and C. hominis., Conclusion: We developed a qPCR-HRM assay that allows Cryptosporidium genotyping. This method is sensitive and able to distinguish three Cryptosporidium species., (Copyright © 2017. Published by Elsevier Ltd.)

Cryptosporidium spp. are a major cause of gastrointestinal diseases in humans worldwide. While a single subtype of Cryptosporidium hominis has been shown to be responsible for several large outbreaks related to water contamination in developed countries, little is known about the epidemiology of C. hominis in developing countries. This study reports the first genetic characterization of C. hominis at the subtype level in several human populations in Tunisia using the gp60 gene. Eighteen isolates were identified as C. hominis by a restriction fragment length polymorphism (RFLP) analysis. The prevalence of this species in different human populations ranges from 1.53% to 13.04% with a high prevalence being reported in immunocompromised children (13.04%) followed by patients with malignent myeloma (5.5%) and HIV-infected patients (4.59%). The gp60 analysis on C. hominis isolates, performed in 14 cases, showed the presence of a single subtype family: "Ia". Different subtypes were identified within this family (A11G1R1, A12R3, A23G1R1, A26G1R1, A27G1R1, A28G1R1). The IaA26G1R1 subtype was the most dominant subtype described in this area (50%). Despite the high genetic diversity of Cryptosporidium spp, a low heterogeneity at the subtype level was observed within C. hominis circulating in Tunisia. This distribution is an indicator for intensive and stable anthroponotic cryptosporidiosis in this region. Besides, the presence of a unique genotype in 5 HIV-infected patients attending the same hospital ward suggests the possible occurrence of hospital-acquired infection and underlines the need to implement preventive measures to avoid nosocomial transmission., (Copyright © 2017 Elsevier Ltd. All rights reserved.)