Using meiobenthic taxa, nematofauna biological traits, and bacterial abundance to assess the effects of the polybrominated diphenyl ethers compound: Case study of tetrabromo diphenyl ether BDE-47.

Trophic web structuring in aquatic sediments is dependent on the biological interactions between metazoans and microbial communities. The presence of pollutants in these biotas can therefore impact the meiofauna structure via the modification of the microbial communities. The current study examined in a laboratory bioassay the response of meiobenthic communities, particularly marine nematode taxa from the Bizerte Lagoon to the effect of the most detected polybrominated diphenyl ether in this aquatic environment, BDE-47. Four doses [D1 (2.5 ppb Dry weight (DW)), D2 (25 ppb DW), D3 (50 ppb DW), and D4 (100 ppb DW)] were gradually applied and sediment microcosms were incubated for 30 days in the presence or absence of meiofauna. Our results show that BDE-47-enriched sediments decreased the meiofaunal taxa and bacterial abundance. A lower taxonomic diversity of the nematodes' general structure was observed with all doses used. The numerical analysis of the two dimensional (2D) non-metric multidimensional scaling (nMDS) plots and the evolution of the relative abundances of each functional group of nematode genus assemblages revealed that the abundance of all biological traits was modified. Nevertheless, only three of the functional traits, adult length, feeding group, and amphid shape, showed a clear difference between the control and the treated microcosms. The similarity percentage analysis (SIMPER) revealed that the average dissimilarity between nematode genera communities and biological traits increased with BDE-47-enriched sediments. The nMDS second-stage ordination of inter-matrix rank correlations for matrices including genera and biological traits showed that the amphid shape was the functional trait closest to the generic distribution. Finally, the Principal Component Analysis (PCA) for the nematode biological traits and bacteria indicated a positive correlation of these microbes with the functional groups [1A, Cr, and ef], and a negative correlation only with the "cla"-type tail shape.

High-performance biological treatment of tuna wash processing wastewater using Yarrowia lipolytica.

It is well known that the lack of an effective treatment of tuna wash processing wastewater may pose substantial environmental and public health hazards. The present work investigates the performance of biological treatment of tuna wash processing wastewater (TWPW) by using Yarrowia lipolytica. Under optimized experimental conditions (pH "6.40-6.50" and 29 °C), Y. lipolytica reduced the pollution level of the crude and the diluted TWPW after only 7 days of incubation. The Yarrowia treatment leaded to a reduction of 66% chemical oxygen demand, 69.8% total organic carbon, 66% salinity, and phosphorus total (100%) removal of the crude TWPW, while the treated-diluted TWPW revealed significant reductions in chemical oxygen demand and total organic carbon (75% and 74%, respectively), as well as salinity (68%). Interestingly, a total removal of nitrogen and phosphorus from the diluted TWPW was obtained. Under high salinity, an important Y. lipolytica biomass of 5 g L-1 is produced with high levels of lipids and protein contents at around 336 ± 12.2 mg g-1 and 302.15 ± 5.44 mg g-1, respectively. The phytotoxicity assessment of the treated TWPW on fenugreek seeds shows promising results, which reveals the good performance of Yarrowia treatment in reducing the toxicity of this wastewater.

Nematodes trophic groups changing via reducing of bacterial population density after sediment enrichment to ciprofloxacin antibiotic: Case study of Marine Mediterranean community.

An experiment was carried out using microcosms to evaluate the impact of the fluoroquinolone antibiotic on nematode trophic groups structure and bacterial abundance. Sediment samples were experimentally enriched with four increasing doses of ciprofloxacin [D1 (50 ppm), D2 (100 ppm), D3 (200 ppm) and D4 (500 ppm)] and compared to non-enriched sediments (used as control). Ciprofloxacin changed the trophic composition of nematodes taxa where the relative abundance of microvores (M), epigrowth feeders (EF) and ciliate consumers (CF), raised in a control microcosm, was highly affected and significantly decreased in response to the increasing doses. Nevertheless, the abundance of deposit feeders (DF), optional predators (FP) and exclusive predators (Pr) showed a significant increase. Results from the multivariate analysis showed a clear impact of this antibiotic on nematode trophic assemblages. Microcosms treated with the three highest doses [D2, D3 and D4] were different from the control. The exceptions were those treated with the lowest dose, D1, and which were grouped with the control. The SIMPER analysis results showed that the average dissimilarity continuously increased in the treated microcosms compared to the control. Furthermore, our results have shown that ciprofloxacin also leads to a significant decrease in bacterial density with the highest dose, which could explain the results obtained for nematode trophic groups distribution. Thus, the bacteriophages nematodes only use bacteria as a nutrition source and the lack or presence in small quantity of this food could induce a decrease in their abundance as well as changing of nematodes groups repartition. Our work demonstrates that the nematode responses were dependent on sediment enrichment with ciprofloxacin and opens new perspectives on the potential impact of antibiotics on functional nematode diversity.

Alleviated Actions of Plantago albicans Extract on Lead Acetate-Produced Hepatic Damage in Rats Through Antioxidant and Free Radical Scavenging Capacities.

The aim of this study was to explore the possible protective mechanisms and to determine the antioxidant capacity of phenolic compounds extracted from Plantago albicans against lead acetate-induced hepatic injury. High performance liquid chromatography-photo diode array/electrospray ionization-mass spectrometry (HPLC-PDA/ESI-MS) assay was used to identify the P. albicans extract phenolic compounds. Animals received 100 mg of lead acetate/kg of body weight (bw) in the drinking water for a period of 30 days. The other groups of rats were orally administered with silymarin (300 mg/kg bw) or the P. albicans extract at two doses (100 and 300 mg/kg of bw), once daily, by gastric gavage for the same time. The P. albicans exhibited high total phenolic, flavonoid, and anthocyanin contents. The antioxidant in vitro activity demonstrated that the P. albicans exhibits an important effect against deleterious reactive species. The in vivo results showed that P. albicans prevented the lead acetate-induced significant changes on serum and liver lipid levels. In contrast, P. albicans succeeded in improving the biochemical parameters of serum and liver bringing them closer to the normal values of the control group. It also significantly promoted (P < .05) pro-inflammatory cytokines (TNF-α, IL-6, and NF-κB) in the liver of the experimental animals. The evaluated sample with HPLC-PDA/ESI-MS method showed to contain 10 dominant polyphenols, 2 hydroxycinnamic acids (p-coumaric acid and chlorogenic acids), 4 flavones (Apigenin, Luteolin, Cirsiliol, and Luteolin-7-O-rutinoside), and an anthocyanin (cyanidin-3-glucoside). Hence, it can be concluded that P. albicans could be a potent source of health-beneficial phytochemicals providing a novel therapy to protect liver against lead exposure.

Gastroprotective effect of leaf extract of two varieties grapevine (Vitis vinifera L.) native wild and cultivar grown in North of Tunisia against the oxidative stress induced by ethanol in rats.

Context: Vitis vinifera leaves are traditionally used in Tunisian folk medicine to treat digestive pathologies.Objective: We aimed to compare the gastroprotective effects of hydromethanolic leaves extracts of wild and cultivated grapes accessions native of Tunisia.Materials and methods: The phytochemical analysis of grapevine leaves extracts was performed. The gastroprotective activity was evaluated by ethanol-induced gastric-ulcer in rats pre-treated with increased doses of the extracts or with the standard omeprazole. Index of gastric secretions (volume, pH and gastric mucus production), stomach wall histology and biochemical parameters were estimated for assessment of anti-secretory and gastroprotective effects of the extracts.Results: Pre-treatment with grapevine leaves extracts decreased significantly gastric volume, gastric mucosal damage and increased significantly gastric juice pH compared with the negative control group. The extracts prevented ethanol-induced decrease of the activity of antioxidant enzymes while the levels of malondialdehyde and of reduced glutathione were decreased significantly. Moreover, the most marked effect was observed at low doses of wild ecotype 'Nefza-I' extracts.Conclusion: The leaves of Vitis species might be suitable as a functional food for therapeutic purpose and demonstrates gastroprotective action in gastric lesions model. Both accessions exhibited gastroprotective effects, but wild 'Nefza-I' ecotype was more effective than cultivar 'Marsaoui'.

Effects of Thymus hirtus sp. algeriensis Boiss. et Reut. (Lamiaceae) essential oil on healing gastric ulcers according to sex.

BACKGROUND: Thymus algeriensis Boiss. et Reut. (Lamiaceae), popularly known as "mougecha" or "mazoukcha" is prolific in Mediterranean regions, mostly in North Africa, and is used in folk medicine to treat of stomach diseases. METHODS: In this study, animals were induced with gastric ulcers using HCl/ethanol (0.3 M HCl/60% ethanol) and treated orally with essential oil of Thymus algeriensis (EOTa) in various doses ranging from 54 mg/kg body weight to 180 mg/kg body weight. RESULT: The dose found to be effective was 180 mg/kg body weight, since this dose brought about a maximum reduction in lesion index in female rats. In gastric tissues, levels of total glutathiones (GSH, GST and GPx) and thiobarbituric acid reactive substances (TBARS) were evaluated. The activities of the antioxidant enzymes, catalase (CAT) and superoxide dismutase (SOD) were measured. Histopathological changes were observed using a cross section of gastric tissue. Chemical analysis revealed the presence of 13 components accounting for 77.7% of the essential oil from dried leaves. Oral administration of EOTa (54, 117 and 180 ml/kg) inhibited HCl/ethanol-induced ulcers. Lesion index was significantly reduced in ulcer induced animals treated with EOTa (HCl/ethanol + EOTa) compared to those ulcerated with HCl/ethanol but with no treatment given. Females showed a greater resistance to ulcers and gastric lesions occurred less often than in males. GSH, pH, enzymic antioxidants, and adherent mucus content were all significantly increased. CONCLUSION: From the data presented in this study, it can be concluded that male rats are more sensitive to gastric ulcers induced by HCl/ethanol than females.