RESUMEN

Idiopathic pulmonary fibrosis (IPF) is a chronic and progressive interstitial disease leading to pulmonary damage and respiratory failure.  We aimed to investigate the effect of prickly pear molasses (PPM) on an experimental model of pulmonary fibrosis induced by bleomycin (BLM) in Wistar rat. Animals were divided into 5 groups: the control group (G1), the BLM group (G2) and three groups (G3, G4, G5) receiving a single intra-tracheal injection of BLM (4 mg/kg) and PPM (at 2, 4.5 and10 %) that was introduced into the diet one week before BLM injection and continued for 3 weeks. Our phytochemical results revealed significant polyphenol and flavonoid content. LCMS analysis revealed the presence of Sinapinic acid, t-ferulic acid, t-cinnamic acid, Caffeic acid, gallic acid and vallinic acid among others. Our histological study revealed significant decrease in collagen deposition in the groups of rats treated with 4.5% and 10% molasses compared to BLM group. Oxidative stress in pulmonary tissues was investigated using catalase (CAT), superoxide dismutase (SOD), and malondialdehyde (MDA) assays. Treatment with PPM normalized the disturbance in the level of these oxidative markers in G3,G4, G5 compared to G2. In conclusion, PPM exhibit antifibrotic and antioxidant activities in BLM model of lung fibrosis.

RESUMEN

Exopolysaccharides (EPS) produced by three Lactic Acid Bacteria strains, Lactococcus lactis SLT10, Lactobacillus plantarum C7, and Leuconostoc mesenteroides B3, were isolated using two methods: ethanol precipitation (EPS-ETOH) and ultrafiltration (EPS-UF) through a 10 KDa cut-off membrane. EPS recovery by ultrafiltration was higher than ethanol precipitation for Lactococcus lactis SLT10 and Lactobacillus plantarum C7. However, it was similar with both methods for Leuconostoc mesenteroides B3. The monomer composition of the EPS fractions revealed differences in structures and molar ratios between the two studied methods. EPS isolated from Lactococcus lactis SLT10 are composed of glucose and mannose for EPS-ETOH against glucose, mannose, and rhamnose for EPS-UF. EPS extracted from Lactobacillus plantarum C7 and Leuconostoc mesenteroides B3 showed similar composition (glucose and mannose) but different molar ratios. The molecular weights of the different EPS fractions ranged from 11.6±1.83 to 62.4±2.94 kDa. Molecular weights of EPS-ETOH fractions were higher than those of EPS-UF fractions. Fourier transform infrared (FTIR) analysis revealed a similarity in the distribution of the functional groups (O-H, C-H, C=O, -COO, and C-O-C) between the EPS isolated from the three strains.

Asunto(s)

RESUMEN

The decomposition of penicillin G and erythromycin antibiotics at concentration of 0.2 mg ml(-1) by gamma irradiation at 50 kGy followed by biological treatment with Cupriavidus metallidurans CH34 was evaluated. Degradation of penicillin G and erythromycin was analyzed using nuclear magnetic resonance analysis (NMR), fourier transform infrared spectroscopy (FTIR), and chemical oxygen demand (COD). The exposure to the absorbed dose of 50 kGy caused degradation of penicillin G and erythromycin in the aqueous solution. The complete disappearance of NMR and FTIR peaks following irradiation confirmed the breakage of the ß-lactam ring in penicillin G, and the decarboxylation and cleavage of the thiazolidine ring and for erythromycin, the complete destruction of the three aromatic rings. Irradiation alone removed 52.8 and 65.5 % of penicillin G and erythromycin, respectively. Further reduction to 12.6 and 14 % of the original penicillin G and erythromycin COD, respectively, was achieved using treatment of the irradiation products with C. metallidurans.

Asunto(s)

RESUMEN

In this study, biological activities of methanolic extracts from Artemisia herba-alba, Ruta chalpensis L. and Peganum harmala L. plants, collected in Centre of Tunisia, were investigated. Results showed an important phenolic composition of Artemisia herba-alba (123.95±4.3g GAE/kg of dry mass). The extract of this plant showed, using different antioxidant assays (DPPH, ABTS and AAPH/linoleic acid methods) and an IFN-γ/LPS induced RAW 264.7 murine macrophages' assay, the highest antioxidant (IC50 (DPPH assay) 20.64±0.84mg/L) and anti-inflammatory (72% inhibition at 150mg/L) activities, respectively. Excepting Peganum harmala L. extract, the two other extracts showed a high anticancer activity against several cell lines (human bladder carcinoma RT112, human laryngeal carcinoma Hep2 and human myelogenous leukemia K562), for A. herba-laba IC50=81.59±4.4, 59.05±3.66 and 90.96mg/L respectively, but not on normal peripheral blood mononuclear cells. All these biological activities are well correlated with the phenolic contents of these extracts. These findings demonstrate the remarkable potential of these plants as valuable source of antioxidants with exhibit original and interesting anti-inflammatory and anticancer capacities.

Asunto(s)

RESUMEN

Prokaryotic diversities of 12 geothermal hot springs located in Northern, Central and Southern Tunisia were investigated by culture-based and molecular approaches. Enrichment cultures for both aerobic and anaerobic microorganisms were successfully obtained at temperatures ranging from 50 to 75°C. Fourteen strains including four novel species were cultivated and assigned to the phyla Firmicutes (9), Thermotogae (2), Betaproteobacteria (1), Synergistetes (1) and Bacteroidetes (1). Archaeal or universal oligonucleotide primer sets were used to generate 16S rRNA gene libraries. Representative groups included Proteobacteria, Firmicutes, Deinococcus-Thermus, Thermotogae, Synergistetes, Bacteroidetes, Aquificae, Chloroflexi, candidate division OP9 in addition to other yet unclassified strains. The archaeal library showed a low diversity of clone sequences belonging to the phyla Euryarchaeota and Crenarchaeota. Furthermore, we confirmed the occurrence of sulfate reducers and methanogens by amplification and sequencing of dissimilatory sulfite reductase (dsrAB) and methyl coenzyme M reductase α-subunit (mcrA) genes. Altogether, we discuss the diverse prokaryotic communities arising from the 12 geothermal hot springs studied and relate these findings to the physico-chemical features of the hot springs.

Asunto(s)

RESUMEN

Carvacrol and mild heat treatment were tested for their efficiency to increase the radiosensitivity of Bacillus cereus in broth. The bacterium was treated with gamma-irradiation alone or in combination with carvacrol at its minimal inhibitory concentration or mild heat treatment for 10 min at 45 degrees C. The effects of this combination of treatments were studied on various parameters: the bacterial viability, the modifications of the cell morphology with scanning electron microscopy (SEM), the cellular fatty acids composition of the membrane quantified by gas chromatography, the intracellular and extracellular adenosine 5'-triphosphate (ATP) concentrations, and the DNA degradation. Combined treatments resulted in additive or synergistic effects as compared to gamma-irradiation alone. A significant modification (P < or = 0.05) of the fatty acid composition and unsaturation ratios was observed. Pretreatment with mild heat or carvacrol before irradiation disturbed the membrane integrity of B. cereus and induced a significant decrease (P < or = 0.05) of the intracellular ATP concentration. SEM observations revealed that the cell membrane was more severely affected with combined treatment than irradiation alone. The electrophoresis analysis showed that DNA degradation by combined treatments was greater than the gamma-irradiation alone.

Asunto(s)

RESUMEN

This present study was carried out to evaluate the effects of gamma irradiation on the fatty acids (FA) and mureins composition of two different radiotolerant bacteria. Bacillus cereus LSPQ 2872 and Salmonella Typhi ATCC 19430 were used for this study. The bacterial strains were treated with a sublethal radiation dose of 1kGy to cause a cellular damage. Gas chromatography (GC) and high performance liquid chromatography (HPLC) analysis were performed to demonstrate respectively the modification of the FA composition and the changes in muropeptide profile. Results obtained show, for both bacteria, that this treatment had a significant effect (P< or =0.05) on the FA content with an increase of unsaturated FA percentage. Substantial changes were also noticed for the relative percentage and the number of the muropeptides. This study represents one of the few to demonstrate the modifications on bacterial membrane as a cellular response to survive the ionising radiation stress.

Asunto(s)