Physicochemical and ecotoxicological approaches for Moknine Continental Sebkha in Tunisia

Degradation of water quality is an emerging issue in many developing countries. In this context, industrial and domestic effluents heavily contaminate the coast of Moknine Continental Sebkha in Tunisia. The present study aimed to biomonitor the seawater quality of the Moknine Continental Sebkha coast using physicochemical and ecotoxicological approaches. The ecotoxicological assessment was performed using three species representing different trophic levels, namely Vibrio fischeri, Selenastrum capricornutum, and Lepidium sativum. In the physicochemical analysis such as BOD (biochemical oxygen demand), COD (chemical oxygen demand), TSS (total suspended solids), TOC (total organic carbon), NO3- (nitrate), AOX (adsorbable organic halogen), the recorded levels of pH and total suspended solids did not comply with the Tunisian standard (NT.09.11/1983). The ecotoxicological data confirmed that the tested water samples displayed toxicity to two test indicators L. sativum and S. capricornutum. A targeted chemical screening of the Moknine Continental Sebkha coast previously performed revealed the presence of total mercury, four phthalate acid esters, and one non-phthalate plasticizer, a fact that could explain the observed ecotoxicological effects and therefore might harm the biotic area and the health of the surrounding population.

Pharmaceuticals and personal care products in Tunisian hospital wastewater: occurrence and environmental risk

Despite concerns about the potential risk associated with the environmental occurrence of pharmaceuticals and personal care products (PPCPs), few studies address the emissions of hospitals to aquatic compartments. We examined within a 3-month sampling period the occurrence and environmental risk of PPCPs in seven Tunisian hospital wastewaters. From personal care products, UV filters, main metabolites, and benzotriazoles were quantified, with benzophenone 3 (oxybenzone, BP3) and benzotriazole (BZT) the most frequently found (71%) at median concentrations in the range 2.43 ± 0.87 ngL-1-64.05 ± 6.82 ngL-1 for BP3 and 51.67 ± 1.67 ngL-1-254 ± 9.9 ngL-1 for BZT. High concentrations were also found for 4-hydroxybenzophenone (4HB) (221 ± 6.22 ngL-1), one of the main metabolites of BP3. The antibiotics ofloxacin and trimethoprim, the anti-inflammatory acetaminophen, the antiepileptic carbamazepine, and the stimulant caffeine were present in all the wastewaters. The highest median concentration corresponded to acetaminophen, with 1240 ± 94 mgL-1 in Tunis Hospital, followed by ofloxacin with 78850 ± 39 μgL-1 in Sousse Hospital. For ecotoxicity assessment, acute toxicity was observed for Daphnia magna and Vibrio fischeri. The toxicity data were used in a hazard quotient (HQ) approach to evaluate the risk posed by the target PPCPs to aquatic organisms. The calculated HQs revealed that marbofloxacin (234 for V. fischeri), enrofloxacin (121 for D. magna), and BZT (82.2 for D. magna and 83.7 for V. fischeri) posed the highest risk, concluding that potential risk exists toward aquatic microorganisms. This study constitutes the first monitoring of UV filters in Tunisian hospital effluents and provides occurrence and toxicity data of PPCPs for reference in further surveys in the country.

Single and combined effects of caffeine and salicylic acid on mussel Mytilus galloprovincialis: Changes at histomorphological, molecular and biochemical levels

Caffeine (CAF) and salicylic acid (SA) are frequently detected in waterbody, though information on their biological impact is poor. This work assesses the effects of CAF (5ng/L to 10µg/L) and SA (0.05µg/L to 100µg/L) alone and combined as CAF+SA (5ng/L+0.05µg/L to 10µg/L+100µg/L) on mussel Mytilus galloprovincialis under 12-days exposure by histomorphology of digestive gland and oxidative stress defense at molecular and biochemical levels. Besides evaluating tissue accumulation, absence of histomorphological damage and haemocyte infiltration highlighted activation of defensive mechanisms. Up-regulation of Cu/Zn-sod, Mn-sod, cat and gst combined with increased catalase and glutathione S-transferase activity were found in CAF-exposed mussels, while SA reduced ROS production and mitochondrial activity. CAF+SA exposure induced differential responses, and the integrated biomarker response (IBR) revealed more pronounced effects of SA than CAF. These results enlarge knowledge on pharmaceuticals impact on non-target organisms, emphasizing the need for proper environmental risk assessment.

Identification of Novel Compounds Inhibiting the Kinase Activity of the CDK5/p25 Complex via Direct Binding to p25

Tamoxifen, the gold standard drug for endocrine therapy for breast cancer, modulates the phosphorylation status of the TAU protein in Alzheimer's disease by inhibiting CDK5 kinase activity. Its binding to p25 prevents CDK5/p25 complexation and hence a decrease of CDK5 activity. In breast tumors, this complex is involved in the proliferation and survival of cancer cells, as well as in the disease's prognosis. Still, the molecular stability of the CDK5/p25 complex following tamoxifen exposure in this cancer type has not yet been clearly deciphered. Here, we report the functional characterization of CDK5 and its p25 regulatory subunit in the absence and presence of tamoxifen. In addition, two novel inhibitors of the kinase activity of the CDK5/p25 complex are identified, both of which would reduce the risk of recurrence of estrogen receptor-positive (ER+) breast cancers and prevent drawbacks induced by tamoxifen exposure. Accordingly, 6His-CDK5 and 6His-p25 have been expressed and purified. Fluorescence anisotropy measurements have been used to assess that the two proteins do form an active complex, and thermodynamic parameters of their interaction were measured. It was also confirmed that tamoxifen directly binds to p25 and inhibits CDK5 kinase activity. Similar observations were obtained using 4-hydroxytamoxifen, an active metabolized form of tamoxifen. Two novel compounds have been identified here that harbor a benzofuran moiety and were shown to target directly p25, and their bindings resulted in decreased CDK5 kinase activity. This encouraging alternative opens the way to the ensuing chemical optimization of this scaffold. It also promises a more specific therapeutic approach that may both tackle the pathological signaling in breast cancer and provide a potential new drug for Alzheimer's disease.

Reuse of treated urban wastewater on the growth and physiology of Medicago sativa L. cv. Gea and Petroselinum crispum L. cv. Commun: correlation with oxydative stress and DNA damage

The freshwater scarcity is one of the major environmental problems, which is why the water reuse has become a possible remedy to cope with the shortage of water needed for agriculture irrigation. This study focuses on the evaluation of the irrigation effect with treated effluent from wastewater treatment plant in Tunisia on parsley (Petroselinum crispum L. cv. Commun) used as human food and alfalfa (Medicago sativa L. cv. Gea) as animal food. In vitro germination test was conducted at different dilution levels of wastewater as rejected into the environment (25, 50, and 100%) and wastewater with further treatment (TWW). Results have shown that wastewater with dilution of 25% as well as TWW positively affected the physiological parameters in comparison with the dilutions 50 and 100%. However, the tap water (TW) applied as control treatment has shown the best effects. Oxidative stress evaluated by malondialdehyde (MDA) content was in agreement with the physiological results and showed that the most stressed seeds were those treated with the dilutions 50 and 100%. A pot trial was also conducted to evaluate the suitability of WW and TWW in comparison to TW. Results have shown that TWW is more adapted than WW for irrigation as an improvement of growth and physiological parameters was recorded. Oxidative stress assessed with MDA and proline content has shown that plants irrigated with WW significantly accumulate MDA and proline compared to TWW. The TW has shown the lowest values. DNA damage was evaluated by extraction and agarose gel electrophoresis. It has revealed degradation of DNA for plants irrigated with WW. According to these results, it can be concluded that TWW can be used for irrigation of plants destined for human or animal foods. So, it can be a hydric alternative to resolve the problem of water deficit in semi-arid countries.

Time- and dose-dependent biological effects of a sub-chronic exposure to realistic doses of salicylic acid in the gills of mussel Mytilus galloprovincialis

Among nonsteroidal anti-inflammatory drugs (NSAIDs) commonly found in seawater and wastewater, salicylic acid (SA) represents one of the most persistent and hazardous compounds for aquatic organisms. This study was therefore designed to elucidate the biological effects of SA in mussel Mytilus galloprovincialis. During a sub-chronic exposure (12 days), mussels were exposed to five realistic concentrations of SA (C1: 0.05 μg/L; C2: 0.5 μg/L; C3: 5 μg/L; C4: 50 μg/L; C5: 100 μg/L) and gills, selected as the target organ, were collected at different time points (T3: 3 days; T5: 5 days; T12: 12 days). Exposure to SA induced no histological alterations in mussel gills, despite a relevant hemocyte infiltration was observed throughout the exposure as a defensive response to SA. Temporal modulation of glutathione S-transferase (GST), catalase (CAT), and superoxide dismutase (SOD) activities suggested the occurrence of antioxidant and detoxifying responses against SA exposure, while lipid peroxidation (LPO), except for a partial increase at T3, was prevented. Inhibition of the cholinergic system was also reported by reduced acetylcholinesterase (AChE) activity, mainly at T12. Overall, findings from this study contribute to enlarge the current knowledge on the cytotoxicity of SA, on non-target aquatic organisms, and might for the enhancement of new ecopharmacovigilance programs and optimization of the efficacy of wastewater treatment plants for mitigation of pharmaceutical pollution in coastal areas.

Contaminants of emerging concern in marine areas: First evidence of UV filters and paraben preservatives in seawater and sediment on the eastern coast of Tunisia

UV filters (UVFs) and paraben preservatives (PBs) are widely used components in many personal care products. However, there has been a rising concern for their endocrine-disrupting effects on wildlife once they reach aquatic ecosystems via recreative activities and wastewater treatment plants effluents. This study addresses UVFs and PBs occurrence in seawater and sediment impacted by tourism and sewage discharges along the coast of Mahdia, center East Tunisia. Samples of water and sediment were collected for 6 months from 3 coastal areas. Among the 14 investigated UVFs, 8 were detected in seawater and 4 were found in sediment. All PBs were present in seawater and only methylparaben (MePB) was detected in sediment. Benzophenone-3 (oxybenzone, BP3), benzocaine (EtPABA), and MePB were present in all water samples with concentrations in the ranges 16.4-66.9, 7.3-37.7, and 17.6-222 ng/L, respectively. However, the highest value, 1420 ng/L, corresponded to octinoxate (EHMC). In sediments, avobenzone (AVO), 4-methyl benzylidene camphor (4MBC), EHMC, 5-methyl-1-H-benzotriazole (MeBZT), and MePB were detected at concentrations within the range 1.1-17.6 ng/g dw, being MePB the most frequently detected (89%). MePB and MBZT presented the highest sediment-water partition coefficients and MePB also showed a positive correlation with total suspended solids' water content. Overall, pollutants concentrations remained rather constant along the sampling period, showing little seasonal variation. This study constitutes the first monitoring of UVFs and PBs on the Tunisian coastline and provides occurrence data for reference in further surveys in the country.

Endocrine-disruptor endpoints in the ovary and thyroid of adult female rats exposed to realistic doses of di-(2-ethylhexyl) phthalate

Di-(2-ethylhexyl) phthalate (DEHP) is the world's most widely used polyvinyl chloride (PVC) plasticizer and is used in virtually every category of flexible PVC. In fact, DEHP is extensively used in food cosmetics and medical packaging. It has become a serious problem in recent years. DEHP can be absorbed into the human body through the air, food, water, and skin. The current study involved intraperitoneal injection of DEHP dissolved in corn oil once daily for 21 consecutive days to investigate the effects of DEHP on the thyroid and the reproductive system in female rats. Results show that ovarian hormones (progesterone and estrogen) decreased significantly in the rats treated with DEHP compared to control. This result is supported by the alteration of folliculogenesis, the decrease of the follicles viability, and the apoptosis of the granulosa cells observed on histological sections of ovary and thyroid in female rats exposed to low doses of DEHP. Histopathological study revealed that DEHP could damage thyroid tissue and disrupt these functions. We also observed cellular damage, particularly in the liver cells, and a significant increase in biochemical parameters such as alanine aminotransferase (ALT) and aspartate aminotransferase (AST) compared to the control group.

Activity of Essential Oils Against Multidrug-Resistant Salmonella enteritidis

We have investigated the antibacterial, anti-biofilm, and anti-quorum sensing potencies of six Essential Oils (EOs) obtained from cinnamon (Cinnamomum verum), thyme (Thymus vulgaris), clove (Eugenia caryophyllata), curcuma (Curcuma longa L.), rosemary (Rosmarinus officinalis L.), and sage (Salvia officinalis). The study was conducted on 20 multidrug-resistant (MDR) S. enteritidis clinical strains. Minimum inhibitory concentrations and minimum bactericide concentrations were displayed by microdilution. The effect on biofilm formation was tested on polystyrene plates. The anti-quorum sensing effect was determined by measuring the inhibition of violacein production by Chromobacterium violaceum CV026. The influence of EOs on the adhesion of Salmonella strains to HT-29 cells was studied. The potency of S. enteritidis to infect and kill Caenorhabditis elegans was evaluated. The cinnamon, thyme, and clove EOs showed remarkable antibacterial properties. Biofilm formation was significantly reduced by the six EOs: 99.10% for cinnamon, 97.64% for clove, 95.90% for thyme, 79.84% for rosemary, 28.98% for curcuma, and 15.55% for sage. The MIC/2 of clove EO exhibited the highest percentage of inhibition of violacein production (99.03%), followed by thyme (91.68%) and cinnamon (84.13%) EOs. Thyme extracts exhibited an important anti-adhesive potency. Clove EO behaves as an effective regulator of Salmonella virulence in nematodes.

Comparison of cellular mechanisms induced by pharmaceutical exposure to caffeine and its combination with salicylic acid in mussel Mytilus galloprovincialis

Urban and hospital-sourced pharmaceuticals are continuously discharged into aquatic environments, threatening biota. To date, their impact as single compounds has been widely investigated, whereas few information exists on their effects as mixtures. We assessed the time-dependent biological impact induced by environmental concentrations of caffeine alone (CAF; 5 ng/L to 10 µg/L) and its combination with salicylic acid (CAF+SA; 5 ng/L+0.05 µg/L to 10 µg/L+100 µg/L) on gills of mussel Mytilus galloprovincialis during a 12-day exposure. Although no histological alteration was observed in mussel gills, haemocyte infiltration was noticed at T12 following CAF+SA exposure, as confirmed by flow cytometry with increased hyalinocytes. Both the treatments induced lipid peroxidation and cholinergic neurotoxicity, which the antioxidant system was unable to counteract. We have highlighted the biological risks posed by pharmaceuticals on biota under environmental scenarios, contributing to the enhancement of ecopharmacovigilance programmes and amelioration of the efficacy of wastewater treatment plants.

Histological endpoints and oxidative stress transcriptional responses in the Mediterranean mussel Mytilus galloprovincialis exposed to realistic doses of salicylic acid

Despite the availability of analytic data, little is known about the toxicity of salicylic acid (SA) on aquatic non-target organisms. The present study aimed at evaluating the impact of SA through a short-term exposure of the Mediterranean mussel Mytilus galloprovincialis to five environmentally relevant concentrations of SA. A set of suitable biomarkers was applied at selected time-points on mussel digestive glands, including histological observations and expression of oxidative stress related genes. The obtained results showed a conspicuous hemocytic infiltration among mussel digestive tubules, as confirmed also by a flow cytometric approach that revealed an increase of halinocytes and granulocytes. Interestingly, a significant dose and time dependent decrease in the expression levels of oxidative stress related genes was found in mussels exposed to SA except for the glutathione S-transferase gene that was significantly up-regulated in a time-dependent manner confirming its important role against oxidant species and in the metabolism of pharmaceuticals.

A multi-biomarker approach for the early assessment of the toxicity of hospital wastewater using the freshwater organism Daphnia magna

Hospital wastewater (HWW) contains different hazardous substances resulting from a combination of medical and non-medical activities of hospitals, including pharmaceutical residues. These substances may represent a threat to the aquatic environment if they do not follow specific treatment processes. Therefore, we aimed to investigate the effects of the untreated effluent collected from a general hospital in Mahdia City (Tunisia) on neonatal stages of the freshwater crustacean Daphnia magna. Test organisms were exposed to three proportions (3.12%, 6.25%, and 12.5% v/v) of HWW. After 48 h of exposure, a battery of biomarkers was measured, including the quantification of antioxidant enzymes [catalase (CAT) and total and selenium-dependent glutathione peroxidase (total GPx; Se-GPx)], phase II biotransformation isoenzymes glutathione-S-transferases (GSTs), cyclooxygenases (COX) involved in the regulation of the inflammatory process, and total cholinesterases (ChEs) activities. Lipid peroxidation (LPO) was measured to estimate oxidative damage. The here-obtained results showed significant decreases of CAT and GSTs activities and also on LPO content in daphnids, whereas Se-GPx activity was significantly increased in a dose-dependent manner. Impairment of cholinesterasic and COX activities were also observed, with a significant decrease of ChEs and an increase of COX enzymatic activities. Considering these findings, HWW was capable of inducing an imbalance of the antioxidant defense system, but without resulting in oxidative damage in test organisms, suggesting that peroxidases and alternative detoxifying pathways were able to prevent the oxidant potential of several drugs, which were found in the tested effluents. In general, this study demonstrated the toxicity of hospital effluents, measured in terms of the potential impairment of key pathways, namely neurotransmission, antioxidant defense, and inflammatory homeostasis of crustaceans.

Estrogenic hazards of short chain phthalates and bisphenols found in cosmetic products

For several years, environmental exogenous agents, called endocrine disruptors, are suspected to interfere with the essential functions of reproduction and development in many living organisms. In this study, endocrine disruptors including five phthalates and two bisphenols contents in finished products were assayed and their estrogenic activity were measured by using the Yeast Estrogen Screen system with respect to human and trout estrogen receptors hERα and rtER_S. Independently of the estrogen receptor, only short-chain phthalates (DBP and BBP) and the two bisphenols exhibited an estrogenic activity. Besides, the risk of three end-products (agro-food, cosmetics, and pharmaceutical) was evaluated before and after forced aging. Only two cosmetics the face cream and the perfume presented a hazard which increases with aging. These results are consistent with the compounds identified by Gas chromatography-mass spectrometry. These findings confirmed that the YES system can be routinely used to evaluate the estrogenic hazards within finished products.

Occurrence and antibiotic resistance of Vibrio parahaemolyticus isolated from the Tunisian coastal seawater

Vibrio parahaemolyticus is a gram-negative bacterium ubiquitous in seawater or estuarine water throughout the world. It is a major cause of seafood gastroenteritis complications. In this study, the presence of V. parahaemolyticus was investigated in 66 seawater samples collected during 2018 from 15 stations spread along the Tunisian coast using selective media including CHROMagar Vibrio media. The results show that only eight samples contained V. parahaemolyticus. However, while Vibrio alginolyticus was detected in all samples; both Vibrio cholerae and Vibrio vulnificus were not found. Nine of the presumed V. parahaemolyticus colonies were purified on tryptic soy agar from eight positive samples then identified by the API 20E biochemical test and confirmed by the presence of a specific target toxR gene. The detection of virulence genes, thermostable direct haemolysin (tdh) and thermostable-related haemolysin (trh), by the polymerase chain reaction (PCR) showed the presence of only two trh-positive isolates. The assessment of antibiotic susceptibility of the V. parahaemolyticus isolated revealed a complete resistance to colistin, amikacin, penicillin and cefotaxime and a total sensitivity to chloramphenicol, nitrofurantoin and sulfamethoxazole-trimethoprim with a multiple antibiotic resistance index (MAR) ranging from 0.4 to 0.5.

Occurrence of Textile Dyes and Metals in Tunisian Textile Dyeing Effluent: Effects on Oxidative Stress Status and Histological Changes in Balb/c Mice

Although it is known that textile wastewater contains highly toxic contaminants whose effects in humans represent public health problems in several countries, studies involving mammal species are scarce. This study was aimed to evaluate the toxicity profile of 90-days oral administration of textile dyeing effluent (TDE) on oxidative stress status and histological changes of male mice. The TDE was collected from the textile plant of Monastir, Tunisia and evaluated for the metals, aromatic amines, and textile dyes using analytical approaches. Metal analysis by ICP-MS showed that the tested TDE exhibited very high levels of Cr, As, and Sr, which exceeded the wastewater emission limits prescribed by WHO and Tunisian authority. The screening of TDE through UPLC-MS/MS confirmed the presence of two textile dyes: a triphenylmethane dye (Crystal violet) and a disperse azo dye (Disperse yellow 3). Exposure to TDE significantly altered the malondialdehyde (MDA), Conjugated dienes (CDs), Sulfhydryl proteins (SHP) and catalase levels in the hepatic and renal tissues. Furthermore, histopathology observation showed that hepatocellular and renal lesions were induced by TDE exposure. The present study concluded that TDE may involve induction of oxidative stress which ensues in pathological lesions in several vital organs suggesting its high toxicity. Metals and textile dyes may be associated with the observed toxicological effects of the TDE. These pollutants, which may have seeped into surrounding rivers in Monastir city, can cause severe health malaise in wildlife and humans.

Coastal Surveillance and Water Quality monitoring in the Rejiche Sea-Tunisia

The aim of this study is to determine physiochemical and bacteriological properties of seawater and sediments from the coast of Tunisia during six successive months. The conductivity was measured using previously calibrated Hach Conductivity meter. Total suspended solid was determined using Whatman GF/C glass fiber filter (Sigma Aldrich), and the turbidity was assessed using a spectrophotometer (UV/Vis). The pH was measured using pH electrodes. Other physiochemical parameters were determined using Pastel UV multiparameter water analyzer (Secomam, aqualabo). Bacterial analysis was displayed by membrane filtration method, and isolates were identified to the species level by Api strips. Susceptibility to antibiotics was determined by disk diffusion methods. Total suspended solid, turbidity, adsorbable organic halogen, chemical oxygen demand, and biochemical oxygen demand were higher than accepted norms in Tunisia. Enterococcus faecalis was detected in all the sites indicating a human fecal contamination, and all the isolates were highly resistant to rifampicin, gentamicin, chloramphenicol, ampicillin, and azithromycin. The situation in Mahdia coast is alarming particularly with the isolation of multidrug resistance strains. It is recommended that the local government provide restrict policies for the treatment and the assessment of municipal wastewater before its discharge into sea. PRACTITIONER POINTS: Coastal Surveillance and Water Quality monitoring in the Rejiche Sea - Tunisia is crucial. Enterococcus faecalis was detected in sea water and sediment samples in the coast of Rejiche. Isolated strains were highly resistant to rifampicin, gentamicin, chloramphenicol, ampicillin and azithromycin.

Identification and quantification of plasticizers, bisphenol, and environmental toxic mineral elements residues in medicines from Tunisian markets

In this study, 18 plasticizer (phthalates, adipates, sebacates, and others) residues in sixteen medicines available in Tunisian pharmaceutical markets are evaluated by MSPD combined with GC-MS. In parallel, in this research, UPLC-MS/MS technique was performed to detect bisphenol A, and cadmium, lead, chromium, cobalt, nickel, mercury, selenium, and arsenic levels were determined by ICP-MS. The maximum daily ingested mass of mineral elements was calculated and compared with permissible daily exposure limits published by USP NF 2013. Our results demonstrated that the 50% of drugs contained similar concentrations of di-ethyl adipate. Di-isobutyl phthalate was found in a single sample with a high concentration (1.07mgkg^-1). Di-methyladipate was also present in only one sample. Diethyl phthalate was detected in three medicines: the highest concentration (17.03mgkg^-1) was found in capsules. The other plasticizers and bisphenol A levels were below the limits of quantification in the all samples. All tested products were safe for use, except two clay-originated products. Concentrations and the maximum daily ingested mass of lead and arsenic were higher than recommended limits. The use of these medicines should require more attention taking into account the serious hazards of heavy metals to human health.

Short-time irrigation on young olive tree (Olea europaea L. cv. Chemlali) with untreated industrial poultry wastewater: investigation of growth parameters and leaves chemical composition

The purpose of this study was to evaluate the short-term irrigation effect with industrial poultry wastewater on young olive trees (Olea europaea L. cv. Chemlali). Industrial poultry wastewater can be considered as a bio-fertilizer due to its richness in nutritive elements (SO₄^2-, HCO₃^-, total nitrogen, and K⁺). The physicochemical analysis of wastewater showed a high concentration of TSS, COD, BOD, COT, NO₃^-, and conductivity. Measurements indicated that poultry wastewater enhanced plant growth, leaves dry matter, and ashes in comparison with tap water, as well as poultry wastewater diluted with tap water; however, a decrease in total soluble sugars (glucose and fructose) was detected in leaves. The determination of fatty acid profile of young olive trees leaves irrigated with poultry wastewater showed richness on saturated fatty acids in comparison with mono- and poly-unsaturated ones. In addition, oleic acid (C_18:1) presented the lowest content in leaves of trees irrigated with poultry wastewater irrigation. According to those results, poultry wastewater lends itself to being a hydric alternative and at the same time a source of nutrients that can help fill the water deficit in semi-arid countries and avoid costly waste disposal for slaughterhouses.

Evaluating the effect of dermaseptin S4 and its derivatives on multidrug-resistant bacterial strains and on the colon cancer cell line SW620

Dermaseptins are peptides found in the skin secretions of Phyllomedusinae frogs. These peptides exert a lytic action on various microorganisms and have no considerable hemolytic effect except dermaseptin S4 (DS4) which exhibits a powerful cytotoxic effect. Therefore, we synthesized several analogs of DS4 in an attempt to find molecules with a weak hemolytic effect and significant bioactivities. In this study, we performed the synthesis of truncated peptides by introducing C-terminal and N-terminal amino acid deletions of the native sequence. All peptide analogs, in comparison with parental peptide, were tested firstly on human red blood cells to work out their cytotoxicity, secondly on the multidrug-resistant bacteria by trying to find MICs, and finally on colon cancer tumor cell line SW620 using the MTT test so as to investigate the anti-proliferative effect. Our results showed that, on the one hand, the N terminus of the native peptide was necessary for the antibacterial activity and the anti-proliferative effect of the peptide. On the other hand, the hemolytic activity was more notable in the sequences broken down on the C-terminal side.

In vivo toxicities of the hospital effluent in Mahdia Tunisia

Hospital effluent (HE) is one of the most important sources of pharmaceuticals released into the environment. This kind of pollution is a recognized problem for both human health and aquatic life. Consequently, in the present study, we assessed the effects of untreated hospital effluent on mice via biochemical and histopathological determinations. Female mice were given free access to water bottles containing untreated HE at different dilutions for 21 days. Then clinical biochemistry and histopathology evaluation were conducted. Serum biochemistry analysis showed the presence of significant increase in cholesterol, triglycerides, glycaemia and total bilirubin. However, phosphatase alkaline and urea activities have been significantly decreased compared to the control group. No significant variation was observed for the rest of the studied parameters (high-density lipoproteins; low-density lipoproteins and uric acid). Additionally, multiple alterations, including cellular necrosis, leucocyte infiltration and congestion, were observed in different tissues of mice exposed to the tested HE.

Factors controlling phytoplankton dynamics in an arid reservoir in Tunisia (case of Sidi Saad dam)

Temporal variation of the phytoplankton community and environmental factors were investigated over 8 months: from January 2018 to November 2018 in the Sidi Saad reservoir (central Tunisia): May, June (spring season), July, August (summer season) September, October and November (autumn season), and January (winter season). The relationships between phytoplankton and environmental factors were explored using Canonical Correspondence Analysis (CCA). General linear models (GLMs) were used to predict the phytoplankton abundance. Analysis of variance (ANOVA) was used to test the hypothesis that the abundance of each group of taxa differed between sampling months. The results of chemical analysis of the reservoir showed that the environment was enriched in nitrates, nitrites, ammonium, and orthophosphate, especially in May. Carlson's trophic index using average chemical variables showed that Sidi Saad has a mesotrophic statute. There is temporal phytoplankton succession in the Sidi Saad reservoir. Cyanophyceae dominated over the year except in winter and late autumn (November and January). Chlorophyceae was the dominant group in winter month. The CCA results showed that six environmental factors, orthophosphates (PO₄^3-), total phosphates (TP), Secchi disc depth (SD), total nitrogen (TN), temperature (T), and nitrite (NO₂^-) had significant influences on the changes in phytoplankton. GLM showed that PO₄^3-, TP, TN, SD, and T were the significant predictors of phytoplankton abundance. Phytoplankton composition is largely dominated by the species Microcystis aeruginosa which formed a bloom with excessive abundance (up to 89.76 billion cell l^-1 in spring). We recommend banning the fishing and their consumption during the period of Microcystis bloom and installing a system of biomonitoring of the levels of toxins in the water.

Monitoring of Environmental Hg Occurrence in Tunisian Coastal Areas

Total mercury (Hg) was determined in 450 environmental samples (seawater, sediment plant and fish) from five Mahdia coastal areas (Tunisia). Tolerable Weekly Intake% (TWI) values, according to the European Food Safety Authority (EFSA), were calculated based on the average metal concentration in fish and the average weekly fish consumption rate. Hg was accumulated mainly in fish and in Posidonia oceanica leaves. Hg in sediment ranged from 1.88 μg/kg dry weight (d.w.) to 7.48 μg/kg d.w., while it was between 0.32 μg/kg and 0.19 μg/kg in seawaters. Our study showed high concentration in Posidonia oceanica in S3 (plant = 16.76 ± 4.48 μg/kg d.w.) as compared to those in S4 sites (plant = 5.33 ± 0.05 μg/kg d.w.). Concentrations for S. aurata and S. salpa in the Rejiche area exceeded the EC 1881/2006 legislation with values of 1.9 mg/kg and 2.5 mg/kg, respectively, and consumers may be exposed to high concentrations of Hg that exceeds the EFSA. The results showed that the fish species should be constantly monitored due to their TWI% of 154.5% for S. aurata and 209.8% S. salpa respectively.

Persistent organic and inorganic pollutants in the effluents from the textile dyeing industries: Ecotoxicology appraisal via a battery of biotests

Today, the textile industry is considered as a leading economic sector in Tunisia. However, this sector demands a huge volume of water and a wide spectrum of chemicals, which is converted into potentially toxic wastewater leading to environmental perturbation and human health toxicity. Assessment of the environmental risks associated with textile wastewater becomes a necessity. In this study, textile dyeing wastewater samples were collected before and after the physico-chemical treatment carried out by textile companies located in Monastir-city-Tunisia and subjected to chemical analyzes in order to determine their physicochemical characteristics and the content of metals and textile dyes. The ecotoxicological assessment was performed using four organisms, namely Selenastrum capricornutum, Vibrio fischeri, Daphnia magna and Lepidium sativum, to represent different trophic levels. Based on chemical data, some physicochemical parameters (e.g. TSS, COD and TSS levels) and metals (e.g. Cr, Hg and Sb) in the textile dyeing effluents were revealed not in compliance with the Tunisian standard. Moreover, high quantities of three disperse dyes have been detected even in the textile dyeing wastewater samples before and after treatments. The ecotoxicological data confirmed that the textile dyeing influents displayed toxic effects to all the test organisms, with Selenastrum capricornutum being the most sensitive organism. While, the above toxic effects were decreased slightly when evaluating the treated effluents. Metals and textile disperse dyes could be associated with the observed toxic effects of the textile influents and effluents. In fact, the treatment process applied by the evaluated companies was only partially efficient at removing metals, disperse dyes and effluent ecotoxicity, suggesting potential risks to aquatic biota. These findings emphasize the importance of applying integrated chemical and biological approaches for continuous evaluation of the toxicity of the treated effluents to predict hazards on the environment.

Photocatalytic and biodegradation treatments of paracetamol: investigation of the in vivo toxicity

Medicines and drugs consumption by all populations of the world can be expected to result in the contamination of the environment since 30-90% of residual drugs will be found into wastewaters. In this study, we investigate the degradation of acetaminophen, selected as a xenobiotic model molecule, via two separate procedures, the TiO₂ impregnated on cellulosic paper photocatalysis, and specific bacterial biodegradation process. Results showed that for initial drug content of 400 mg/L and after 5 hours of processing, around 85% of paracetamol was photocatalytically degraded. The use of Pseudomonas putida E1.21 isolate allowed an abatement of around 92% after 32 h of processing. The acetaminophen toxicity conducted in vivo on laboratory mice showed a net decrease of the creatinine release and enzymes activities like ALP, ALT, AST, and LDH decreased significantly (p < 0.05) when mice were treated distinctly by acetaminophen treated with UV/TiO₂ and the Pseudomonas putida E1.21 strain compared with the control experiments. CAT, MDA, and AchE serum level disruption measurement indicated a serious affection of the mice antioxidant system. These results were found to be in correlation with the ones of the histological analysis of the liver and kidney.

Organic pollutants in marine samples from Tunisian coast: Occurrence and associated human health risks

140 contaminants belonging to various classes (organochlorine and organophosphorus pesticides, pyrethroid insecticides, carbamates, fungicides, acaricides, herbicides, synergists, insect growth regulators, polychlorobiphenyls, polycyclic aromatic hydrocarbons) were simultaneously analysed by GC-MS/MS in marine sediments, aquatic plant leaves and fish tissues samples. A total of 260 samples from five stations along the coast of Tunisia were evaluated. The results highlight that only 28 residues (12 polychlorobiphenyls, 8 organochlorine pesticides, 7 polycyclic aromatic hydrocarbons and triphenyl phosphate) were detected at levels higher than relative LOQ values. The amounts in sediment samples were compared with Sediment Quality Guidelines (SQGs) showing that the values are acceptable and no toxic effect is expected on aquatic organisms. A little variation of contaminant residues in sediment samples among coastal stations was recorded. Namely, with respect to almost all polychlorobiphenyls and organochlorine pesticides, higher values were recorder in summer. With respect to almost all polycyclic aromatic hydrocarbons, higher values were recorder in autumn. Aquatic plant leaves showed a residue accumulation higher than that of other compartments of marine system. The data about fish samples (Sparus aurata and Sarpa salpa, the two most frequently caught fish species at five sites on the central coast of Tunisia) do not pose direct hazard to human health because values were lower than protection limits.

Ecotoxicity profile of heavily contaminated surface water of two rivers in Tunisia

Persistent organic and inorganic contaminants generated by industrial effluent wastes poses a threat to the maintenance of aquatic ecosystems and public health. The Khniss and Hamdoun rivers, located in the central-east of Tunisia, receive regularly domestic and textile wastewater load. The present study aimed to survey the water quality of these rivers using physicochemical, analytical and toxicological approaches. In the physicochemical analysis, the recorded levels of COD and TSS in both samples exceed the Tunisian standards. Using the analytical approach, several metals and some textile dyes were detected. Indeed, 17 metals were detected in both samples in varying concentrations, which do not exceed the Tunisian standards. The sources of metals pollution can be of natural and anthropogenic origin. Three textile disperse dyes were detected with high levels compared to other studies: the disperse orange 37 was detected in the Khniss river with a concentration of 6.438 μg/L and the disperse red 1 and the disperse yellow 3 were detected in the Hamdoun river with concentrations of 3.873 μg/L and 1895 μg/L, respectively. Textile activities were the major sources of disperse dyes. For both samples, acute and chronic ecotoxicity was observed in all the studied organisms, however, no genotoxic activity was detected. The presence of metals and textile disperse dyes could be associated with the ecotoxicological effects observed in the river waters, in particular due to the industrial activity, a fact that could deteriorate the ecosystem and therefore threaten the human health of the population living in the study areas. Combining chemical and biological approaches, allowed the detection of water ecotoxicity in testing organisms and the identification of possible contributors to the toxicity observed in these multi-stressed water reservoirs.

Phthalates and non-phthalate plasticizers in Tunisian marine samples: Occurrence, spatial distribution and seasonal variation

Seawater, sediment, seagrass and fish from several sites along the Tunisian coast were monitored for several phthalate esters (PAEs) and non-phthalate plasticizers (NPPs) during 2018-2019. In water and sediment, NPPs were higher than PAEs, being di(2-ethylhexyl) phthalate (DEHP, 0.0717 and 4.59 μg/g), and di(2-ethylhexyl) terephthalate (DEHT, 0.634 and 2.42 μg/g) most abundant. As expected, sediments acted as a sink for plasticizers, thus revealing a stronger contamination than water. Seagrass was less contaminated than fish, being DEHP (0.726 and 1.77 μg/g) and DEHT (9.19 and 23.2 μg/g) predominant. Biota poorly concentrated/accumulated plasticizers from water and sediment depending on the logK_oct/wat and water solubility of single congeners. The spatial distribution of plasticizers was affected by the proximity to anthropogenic sources and the rate of coastal currents; whereas their seasonal variation may be related to the length of time of touristic/industrial inputs and factors such as rainfall and urban stormwater runoff.

Assessment of natural coagulants to remediate Tunisian textile wastewater by combining physicochemical, analytical, and toxicological data

Due to the complexity and variability of textile wastewater composition, a constant search for new treatment strategies that are efficient, eco-friendly, and cost-effective is mandatory. In the present study, the efficiency of coagulation-flocculation using biocoagulants derived from cactus Opuntia ficus indica and eggplant Solanum melongena to remove toxic compounds from Tunisian textile wastewater samples was evaluated by combining assays to investigate physicochemical properties and in vitro (geno)toxicity with analytical chemistry. Both natural coagulants could significantly improve the physicochemical properties of the textile wastewater samples compared to the traditionally used chemical coagulant. The highest rate of decolorization was achieved after treatment with the cactus-derived coagulant. The analytical study revealed the presence of only crystal violet dye (CV) in only one sample. Both natural coagulants were able to remove CV, which may (partially) explain the decolorization of the treated samples. Only one untreated textile effluent induced a genotoxic response in the VITOTOX^® assay. The genotoxic effect was not linked to the presence of CV and was no longer observed after treatment with each of the natural coagulants, suggesting the effectiveness of the remediation treatments to remove potentially genotoxic compound(s). However, in the other genotoxicity tests, no biologically relevant effects were observed for any of the tested samples. In conclusion, although the physicochemical data indicate that the use of natural coagulants (cactus and eggplant) could be an interesting alternative treatment process to the chemical coagulant for detoxifying textile effluents, these results were only partially supported by the toxicological and analytical data.

Optimization of extraction with salicylic acid, rheological behavior and antiproliferative activity of pectin from Citrus sinensis peels

A Box-Behnken design was used to optimize extraction temperature, extraction time and concentration of the salicylic acid to obtain a maximum polysaccharide yield from Citrus sinensis peels. The optimal settings were: extraction time 3 h, extraction temperature 80 °C and concentration of the salicylic acid 1.5%. Under these conditions, the experimental yield and uronic acid content were 11.74% and 66.9% respectively. Preliminary characterization was performed via FT-IR, SEC/MALS/VD/DRI and GC-MS after hydrolysis. SEC analysis showed that the extracted polysaccharide had a weight average molar mass of 350 kDa and an intrinsic viscosity of 640 mL/g. The GC-MS results revealed that the extracted polysaccharide was composed of arabinose 56.7%, galactose 17.8%, xylose 13.8%, rhamnose 5.1%, mannose 2.5% and glucose 1.5% suggested a rhamnogalacturonan pectin type I with a degree of esterification of 50.9% (IRTF). The flow curve and the dynamic frequency sweep were obtained at 10, 20, 30 and 40 g/L in water and at 30 g/L in presence of CaCl₂ or NaCl at 1 mol/L. The solutions showed shear-thinning behavior fitted with Ostwald-De Waele model, except 10 g/L with a Newtonian behavior. The apparent viscosity and, the G' and G" moduli increase with PACO concentration in agreement with a slow-down of the dynamic chain. In the presence of CaCl₂ or NaCl the reduction of electrostatic repulsions between pectin chains decreases the rheological parameters. The effect is less sensitive with CaCl₂ due to intermolecular interactions. The antiproliferative activity of the extracted pectin on human Caco-2 and Hep-2 cells was very interesting with an IC₅₀ 1.4 and 1.8 μg/mL respectively.

High leaf fluctuating asymmetry in two native plants growing in heavy metal-contaminated soil: the case of Metlaoui phosphate mining basin (Gafsa, Tunisia)

In order to estimate pollution impact in soil and plants by phosphates mining activities, three mining sites and one control site were selected around Metlaoui (phosphates basin of Gafsa, southern Tunisia) in March 2019. Heavy metal concentrations in soil and in two native plants (Moricandia arvensis and Diplotaxis harra: Brassicaceae) were measured using atomic absorption spectrometry. Development instability was estimated using leaf fluctuating asymmetry of the two plant species. The results showed that the soils of the Metlaoui sites contain higher levels of Cd, Ni, Zn, and Cr compared with control site (maximum of 33.225 ± 2.588; 100.86 ± 0.314; 180.267 ± 16.103; and 16.554 ± 0.313 ppm, respectively). These levels are higher than the maximal contents tolerated in soils. Heavy metals also occurred at high concentrations in plant organs in Metlaoui sites especially in leaves. Cadmium and Zn concentrations in these plants exceed the phytotoxic level (with maximum of 20.498 ± 0.627 ppm and maximum of 337.901 ± 16.686 ppm, respectively). Statistical analysis showed that fluctuating asymmetries (FA) of leaves of the two sampled plants are higher in mining sites compared with control. Pearson correlation and PCA analysis showed that FA is related to Cd, Ni, and Zn concentrations in soil. The results indicate that phosphate extraction and laundries in the mining sites caused heavy metal pollution in soil that accumulates in plant organs and caused also development instability. Our study showed that Moricandia arvensis may have the potential for phytoremediation.

Toxic effect of alpha cypermethrin, an environmental pollutant, on myocardial tissue in male wistar rats

α-Cypermethrin (CYP) is a pyrethroid insecticide-like environmental pollutant, widely found in the environment. New research links exposure to high levels of CYP to health damage; however, little is known about the effect of CYP on cardiovascular disease. The purpose of the present study was to evaluate, for the first time, biochemical and cardiovascular changes in male rats resulting from subchronic CYP exposure. The animals were divided into three groups: group 1 served as the control, group 2 (CYP1) received 4 mg/kg of CYP by gavage, and group 3 (CYP2) received 8 mg/kg of CYP by gavage, for 8 weeks each. Results showed that both CYP1 and CYP2 markedly increased plasma concentrations of cardiac markers (LDH, CK-MB, and troponin-T). Moreover, compared to the control group, CYP treatment elevated cardiac oxidative stress, as shown by increased MDA level and decreased activity of SOD, CAT, and GSH-Px. In addition, CYP2 caused a significant increase of 42% the concentration of total cholesterol and more than 75% in triglycerides compared to the control group. Furthermore, DNA fragmentation and collagen deposition were both amplified owing to CYP toxicity. This harmful effect was confirmed by a histological study using H-E and Sirius Red staining. Overall, our results clearly proved the cardiotoxicity caused by α-cypermethrin.

Monitoring hospital wastewaters for their probable genotoxicity

Hospitals' effluents contain a considerable amount of chemicals. Considering the significant volume of wastewater discharged by hospitals, the presence of these chemicals represents a real threat to the environment and human health. Thus, the aim of this study was to evaluate the in vivo and in vitro genotoxicities of three wastewater effluents collected from Tunisian hospitals. The liver of Swiss albino male mice, previously treated with different doses of the hospital wastewaters, was used as a model to detect DNA fragmentation. Our results showed all the hospital effluents caused significant qualitative and quantitative hazards in hepatic DNA. The wastewater collected from Sfax hospital exhibited the highest genotoxic effect, which may be explained by the presence in this effluent of some toxic micropolluants. There was a significant increase in genotoxicity, proportionally to the concentration of effluent. However, the vitotox assay did not show any significant genotoxicity on Salmonella typhimurium TA104 in the presence or absence of microsomal fraction S9. The ratio gentox/cytox was lower than the threshold 1.5. This study assessed the toxicological risk issued from Tunisian hospital wastewaters, which is potentially very harmful, and it has been pointed out that wastewater treatment requires special attention.

Occurrence of 40 pharmaceutically active compounds in hospital and urban wastewaters and their contribution to Mahdia coastal seawater contamination

In the present study, the occurrence of 40 pharmaceuticals belonging to several therapeutic groups was investigated for the first time in hospital effluent, wastewater treatment plant influent and effluent, and seawater in Mahdia, Tunisia. Forty-six samples were collected within a 6-month sampling period. Pharmaceuticals were analyzed using solid-phase extraction followed by ultra-performance liquid chromatography-triple quadrupole mass spectrometry. Thirty-three out of the forty target compounds were detected over a wide concentration of ranges, from nanograms per liter to micrograms per liter, depending on the type of sample. Maximum values were detected for caffeine at 902 μgL^-1 in hospital wastewater. This compound, as well as salicylic acid, sulfadiazine, and sulfamethizole, were detected in all samples. The average concentration of total pharmaceuticals in hospital wastewater (340 μgL^-1) was higher than those detected in influent and effluent wastewater and seawater (275.11 and 0.2 μgL^-1, respectively). Risk quotients (RQs) were also estimated to provide a preliminary environmental risk assessment and results revealed that sulfadiazine, sulfamethoxazole, and fluoxetine could pose medium/high risk to the tested aquatic organisms for maximum measured concentrations in wastewater (including hospital and WWTP samples). Although the measured environmental concentrations (MECs) detected in seawater samples might not pose a toxic effect to the aquatic organisms (except for salicylic acid, sulfamethoxazole and fluoxetine), further researches are needed due to the continuous release of wastewater in the environment and the limited efficiency of wastewater treatment processes.

Major, minor and trace element concentrations in spices and aromatic herbs from Sicily (Italy) and Mahdia (Tunisia) by ICP-MS and multivariate analysis

Element contents in different types of spices and aromatic herbs collected from Italy and Tunisia were evaluated. The aim was to evaluate: the possible differences and/or similarities among the analyzed samples; if it is possible related the samples to their geographical origins; the nutritional quality and the potential health risks. Potassium, Ca, Mg and Ni were low in laurel and rosemary; mint and thyme showed the highest Na and the lowest Se contents; arsenic and Cd levels were found highest in verbena which had also the lowest Hg content; lastly, black pepper had the highest Mn and the lowest Pb contents. Instead discrimination between Italian and Tunisian samples for each spices and aromatic herbs under analysis was achieved by PCA. Essential elements intake through samples was small. Levels of Pb in some samples exceed the maximum allowable level, but any safety risk for consumers is excluded.

Cardioprotective effects of (E)-4-hydroxy-N'-(1-(3-oxo-3H-benzo[f]chromen-2-yl)ethylidene)benzohydrazide: a newly synthesized coumarin hydrazone against isoproterenol-induced myocardial infarction in a rat model

The current study was carried out to evaluate the effect of pretreatment and co-treatment with a newly synthesized coumarin hydrazone, (E)-4-hydroxy-N'-(1-(3-oxo-3H-benzo[f]chromen-2-yl)ethylidene)benzohydrazide (hereinafter EK6), against isoproterenol-induced myocardial infarction in rats. Changes in biochemistry, cardiac biomarkers, electrocardiography, and histopathology after treatment with EK6 or acenocoumarol (Sintrom) were studied. Animals were randomly divided into 4 groups: vehicle control (C), isoproterenol + Sintrom (ISO + Sin), isoproterenol + EK6 (ISO + EK6), and isoproterenol (ISO). Myocardial infarction was induced by subcutaneous ISO administration at a dose of 85 mg·kg^-1·day^-1 with a drug-free interval of 24 h on days 6 and 7. Treatment with ISO led to significant elevation (p < 0.05) in serum levels of cardiac injury biomarkers, namely cardiac troponin-T, lactate dehydrogenase, creatine kinase-MB, alanine aminotransferase, and aspartate aminotransferase compared with levels in the vehicle control. A change in the lipid profile was also observed as a significant increase in total cholesterol and triglycerides. Furthermore, ISO caused significant alterations in the electrocardiogram pattern, including significant ST-segment elevation, significant decreased R wave amplitude, and significant increase in heart rate (16%) as well as marked changes in the histopathology of the heart tissue. Pretreatment and co-treatment with newly synthesized coumarin hydrazone restored all ISO-induced biochemical, lipid, cardiac, and histopathological changes in rats with myocardial infarction.

Human urine contamination with environmental pollutants: simultaneous determination using UPLC-MS/MS

Paraben derivatives are widely used as an antifungal, antimicrobial preservative in cosmetic products, pharmaceuticals, and food. These molecules are called endocrine disruptors (EDCs). The exposure of the human body to paraben derivatives needs further study and for this purpose 200 urine samples were collected from Tunisian men and women aged between 5 and 90 years to determine three paraben derivatives: methylparaben (MP), ethylparaben (EP) and propylparaben (PP) using ultra performance liquid chromatography-tandem mass spectrometer (UPLC-MS/MS). The three major parabens were found in 95 urine samples. The obtained results indicate that MP, EP, and PP were detected in 57%, 46%, and 40% of all samples, respectively. Urinary concentration for the three parabens was in the range of 0.88-84.46 ng/mL, 0.52-29.2 ng/mL, and 0.51-28.17 ng/mL of PP, MP, and EP, respectively. In addition, the concentrations of the paraben derivatives in women were higher than those of men. These findings indicate that the exposure occurs from common products (foods, cosmetics, and pharmaceuticals). The Tunisian authorities should control the composition of packaging of these common products in order to protect humans against EDCs.

Effectiveness of dairy treated wastewater and different irrigation systems on the growth, biomass and fruiting of a Tunisian olive orchard (Olea europaea L., cv Chemlali)

The effectiveness of dairy treated wastewater (TWW) was evaluated, in comparison with tap water (TW), on a Tunisian olive orchard (Olea europea, cv Chemlali), irrigated manually (MI) and by surface dripping (SDI). To this purpose, tree growth, biomass and fruiting were monthly tested for a one-year period. Similar trunk diameters, nodes/tree, root lengths were obtained, independently of source and system of irrigation. Also, comparable tree length and leaf area, shoots/tree and biomass, were observed between TWW and TW plants. However, such parameters improved under SDI rather than MI. Fruiting occurred only in TWW and TW trees treated by MI. Concerning growth, biomass and fruiting, TWW represented a valid alternative source for the irrigation of olive orchard, especially in Tunisia, already facing the freshwater scarcity. Monitoring of soil, TWW, fruits and oil will be required to validate the use of such effluent for olive orchard irrigation.

Organic contamination of Italian and Tunisian culinary herbs and spices

Contaminants belonging to various classes, as polychlorobiphenyls, polycyclic aromatic hydrocarbons, organochlorine pesticides, organophosphorous pesticides, pyrethroid insecticides, fungicides, herbicides, synergists, carbamates, acaricides and insect growth regulators were simultaneously analysed by GC-MS/MS in 118 Italian and Tunisian culinary herbs and spices. The results obtained in Italian samples shown that laurel samples were the most contaminated with the presence of 15 residues on 140, whereas in rosemary (max value of 35 ng/g for cis-chlorfenyvinphos) and oregano (max value of 118.16 ng/g for ethion) some occasional residues can be observed, but always lower than the maximum residue levels; all the others samples shown no contamination. Among Tunisian samples, only rosemary contains a notably high content of pollutants exceeded the EU maximum residue limits (i.e., alachlor and phosalone with level of 359.2 and 43.3 ng/g, respectively), while oregano was determined to be free of contaminant residues. Considering the comparison among the different organic pollutants in Italian and Tunisian spices and herbs evaluated and the differences observed in this study a harmonization of regulation on contaminant residues in herbs and spices for human consumption should be needed, considering their increased use in diet and cooking.

Optimization of polysaccharides extraction from quince peels: partial characterization, antioxidant and antiproliferative properties

In this study, Box-Behnken Design was used to optimize the ultrasonic extraction of polysaccharides from quince peels (QPPs) by ascorbic acid and the effect of extraction temperature, extraction time and pH was evaluated. Under optimized conditions of temperature 90 °C, 60 min sonication time and pH = 3.26, the extraction yield, the galacturonic acid yield and the concentration of sample required to scavenge 50% of 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic) acid (ABTS) values of QPPs were respectively 10.25%, 3.86% and 1.35 mg/mL. The QPPs extracted under optimum conditions was characterized by Fourier transform infrared spectroscopy (FTIR), Nuclear magnetic resonance (¹H NMR) and Size exclusion chromatography (SEC/MALS/VD/DRI). The monosaccharide analysis revealed that arabinose was the most abundant, followed by galactose, glucose, mannose and xylose. Moreover, QPPs showed significant antioxidant activities (2,2-diphenyl-1-picrylhydrazyl (DPPH) and Ferric- reducing antioxidant power (FRAP)) and reduced viability of human Caco-2 and murine B-16 cell lines in a dose-dependent manner. Hence QPPs could be used as antitumor agent in functional foods andpharmaceutical industries.

Preliminary evaluation of plasticizer and BPA in Tunisian cosmetics and investigation of hazards on human skin cells

In this study, 18 plasticizer (phthalates, adipates, sebacates, and others) and BPA residues in some cosmetic samples collected from Tunisian market are evaluated by micro-matrix solid-phase dispersion combined with GC-MS. In parallel, the impact of these molecules and the cosmetics in the human epithelial cell lines is investigated. The cytotoxic activity of cosmetic extracts is evaluated in vitro against B16 and Hep-2 human skin cell lines using the 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide assay. This study shows that the tested cosmetic products could constitute a hazard to the consumer health and wellness and that strict safety analysis on cosmetic products needs to be carried out before they are marketed.

Plasticizers and BPA Residues in Tunisian and Italian Culinary Herbs and Spices

In the present study, 18 plasticizers and residues in 10 different Tunisian and Italian culinary herbs and spices (black pepper, mint, caraway, coriander, oregano, rosemary, thyme, fennel, verbena, and laurel) were determined by GC/MS. Di-methylphthalate, di-(2-methylpropyl)adipate, di-n-butyladipate, di-propylphthalate, benzylbenzoate, di-phenylphthalate, and bisphenol A were lower than their LOQ in all 118 samples. Among the Tunisian samples, di-(2-ethylhexyl)phthalate was found in all types of samples and di-butylphthalate in 50% of types; all other phthalates were rarely dectected. Among the adipates, only di-methyladipate was found in 90% of types; di-ethyladipate was seldom found and di-(2-ethylhexyl)adipate only in samples of caraway. Di-(2-ethylhexyl)terephthalate was found in all types of samples; di-(2-ethylhexyl)sebacate was detected rarely but with high values. Among the Sicilian samples, di-ethylphthalate and di-(2-methylpropyl)phthalate were detected only in samples of mint; di-methyladipate, di-butylphthalate, and benzylbutylphthalate were identified in oregano and laurel; di-(2-ethylhexyl)terephthalate and di-(2-ethylhexyl)sebacate only in oregano. In any case, the results suggested that intake of these contaminants through spices and herbs is not a dangerous risk to the consumers. Probably, as already observed for the other food, these contaminants could result from pollution of the environment (air, water, and/or soil) and/or farming methods.

PRACTICAL APPLICATION

Plasticizers and BPA in Tunisian and Italian spices were determined by GC/MS. Tunisian spices seem to contain more residues than Italian samples. Intake of these contaminants by spices is not a dangerous risk to the consumers. These pollutants could result from environmental pollution or agricultural practices.

Contribution of adiponectin polymorphisms to the risk of coronary artery disease in a North-African Tunisian population

BACKGROUND

Adiponectin, an adipocyte-derived protein, is known to play a key role in the processes leading to atherosclerosis and coronary artery disease (CAD) through its anti-atherogenic, anti-inflammatory, antioxidative, and anti-apoptotic properties. In the current study, we have studied the association of two single nucleotide polymorphisms (SNPs) +45 T>G (rs2241766) and +276 G>T (rs1501299) of the adiponectin gene with coronary artery disease (CAD) on an Arab/North-African population from Tunisia.

METHODS

Subjects comprised 277 patients with angiographically demonstrated CAD and 269 age- and gender-matched control subjects. The adiponectin genotypes were performed by polymerase chain reaction-restriction fragment length polymorphism analysis (PCR-RFLP). The contribution of adiponectin variants to CAD was analyzed by haplotype and regression analysis.

RESULTS

Adiponectin +45T>G and +276G>T genotypic and allelic distributions did not show a significant difference between cases and controls. Similarly, no association with CAD was observed for the haplotype analysis. Assuming dominant model of transmission for both polymorphisms and after adjustment of a number of traditional risk factors for CAD, logistic regression analysis showed an association of SNP +45 T>G with increased risk of developing CAD [adjusted OR (95% CI) = 2.59 (1.17-5.70); P = .01]. However, SNP + 276 G>T is associated with decreased risk of developing CAD [adjusted OR (95% CI) = 0.47 (0.22-0.97); P = .04].

CONCLUSION

There is no allelic or genotypic association of +45 T>G and +276 G>T of the adiponectin gene with CAD in the Tunisian population.

Persistent plasticizers and bisphenol in the cheese of Tunisian markets induced biochemical and histopathological alterations in male BALB/c mice

Clinical evidences, experimental models, and epidemiology of many studies suggest that phthalate-based plasticizers, aliphatic ester, and bisphenol A (BPA) have major risks for humans by targeting different organs and body systems. The current study has been designed firstly to analyze three categories of cheese with and without their exposure to the sun and packed in packages with an inner surface plastic-covered film in order to identify the dibutyl phthalate (DBP); benzyl butyl phthalate (BBP); bis(2-ethylhexyl) phthalate (DEHP); diisodecyl phthalate (DiDP); diisononyl phthalate (DiNP); and 1,2-cyclohexane dicarboxylic acid diisononyl ester (DINCH) by GC-MS/MS, except for the bisphenol A, which is by UPLC-MS/MS, and secondly to assess the toxicity of the identified chemical molecules and cheese samples on the liver and kidney of mice. Our results showed that the cheese contains high quantities of DBP and DEHP with the concentrations up to 0.46 and 2.339 mg/kg, respectively. Other types of cheese, such as rolled and triangular cheeses, contain little quantities of the all substances at concentrations below the standard limits. In vivo, the obtained data clearly demonstrated that the acute administration of DBP, DEHP, and the tested cheese significantly induced liver and kidney injuries in mice manifested by a rise in plasma alanine aminotransferase, aspartate aminotransferase, blood urea nitrogen, lactate dehydrogenase, urea, creatinine, and uric acid when compared with control animals. In addition, the histopathological study confirmed the perturbation of biochemical parameters and showed that the hepatic and renal structures were altered. Indeed, the hepatotoxic and nephrotoxic effects are more pronounced when cheese was exposed to the sun.

UPLC-MS/MS analysis of antibiotics in pharmaceutical effluent in Tunisia: ecotoxicological impact and multi-resistant bacteria dissemination

The UPLC MS/MS analysis showed the presence of the two antibiotics in the pharmaceutical industry discharges during 3 months; norfloxacin and spiramycin which were quantified with the mean concentrations of 226.7 and 84.2 ng mL^-1, respectively. Sixteen resistant isolates were obtained from the pharmaceutical effluent and identified by sequencing. These isolates belong to different genera, namely Citrobacter, Acinetobacter, Pseudomonas, Delftia, Shewanella, and Rheinheimera. The antibiotic resistance phenotypes of these isolates were determined (27 tested antibiotics-discs). All the studied isolates were found resistant to amoxicillin and gentamicin, and 83.33% of isolates were resistant to ciprofloxacin. Multiple antibiotic resistances were revealed against β-lactams, quinolones, and aminoglycosides families. Our overall results suggest that the obtained bacterial isolates may constitute potential candidates for bioremediation and can be useful for biotechnological applications. Genotoxic effects were assessed by a battery of biotests; the pharmaceutical wastewater was genotoxic according to the bacterial Vitotox test and micronuclei test. Genotoxicity was also evaluated by the comet test; the tail DNA damages reached 38 and 22% for concentrated sample (10×) and non-concentrated sample (1×), respectively. However, the histological sections of kidney and liver's mice treated by pharmaceutical effluent showed normal histology and no visible structural effects or alterations as cytolysis, edema, or ulcerative necrosis were observed. Residual antibiotics can reach water environment through wastewater and provoke dissemination of the antibiotics resistance and induce genotoxic effects.

Identification and risk assessment of human and veterinary antibiotics in the wastewater treatment plants and the adjacent sea in Tunisia

In the following study, we came up with and validated a prompt, sensitive and precise method for the simultaneous determination of 56 antimicrobial drugs (tetracyclines, sulfonamides, β-lactams, macrolides and quinolones) using the ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). This method was implemented with success to determine antibiotics in samples collected from four wastewater treatment plants and five coasts in Tunisia. Results showed the presence of high concentrations of antibiotics that ranged from 0.1 to 646 ng mL^-1, which can induce many negative impacts on health and the environment. For this reason, we have opted to evaluate toxicity of wastewater samples using a battery of biotests. In fact, genotoxicity was assessed using three tests: Vitotox, comet and micronucleus assays. The input and output of wastewater treatment plants induced a strongly genotoxic effect on the Salmonella typhimurium TA104 prokaryotic Vitotox assay. This result was confirmed using the comet and the micronucleus assays performed on the human liver hepatocellular carcinoma cells. The genotoxic power of the tested wastewater treatment plants' samples could be attributed to the presence of the higher quantities of antibiotics that are detected in these samples and to the antibiotic and organic compound cocktails.