Noureddine Allouche

Detrimental effects of high molecular-mass polyphenols on olive mill wastewater biotreatment

Research was undertaken to investigate whether low, medium or high molecular-mass polyphenolics were the most problematic compounds for olive mill wastewater (OMW) biotreatments. For this reason, three polyphenolic fractions were isolated by ultrafiltration of crude OMW and characterized by GC/MS and gel filtration analysis. When P. chrysosporium was cultivated in the presence of F1 polyphenolic fraction (F1 60 kDa) was observed. Lignin peroxidase (LiP) was detected as traces for the F1 fraction and undetected in the case of F3 one. Moreover, increasing the molecular-mass of aromatics led to decreases in levels of depolymerization and COD removal by P. chrysosporium cultures. The use of a lignin peroxidase induction medium has a positive effect on the high molecular-mass fraction decolorization and a high degree of decolorization paralleled the appearance of LiP activity in the extracellular fluid. By comparison to the synthetic medium used, LiP production was delayed in the presence of F1 fraction but strongly inhibited (80% loss) in the presence of F3 fraction. The F1 fraction was well degraded aerobically by P. putida DSM3932 (pWWO) and A. eutrophus DSM 4057 (pJP3) or an activated sludge consortium while F3 resisted degradation by the OMW-acclimated activated sludge. Moreover, continuous anaerobic biomethanization experiments conducted in parallel with the different fractions showed that at the same hydraulic retention time (26 days), the F1 fraction was bioconverted into methane at high yield while F3 fraction was poorly biodegraded.

Hypoglycemic and antioxidant effects of phenolic extracts and purified hydroxytyrosol from olive mill waste in vitro and in rats.

This study aimed to evaluate the effect of phenolic extract and purified hydroxytyrosol (HT) from olive mill waste (OMW) on oxidative stress and hyperglycemia in alloxan-induced diabetic rats. The OMW biophenols were extracted using ethyl acetate. The obtained extract was fractionated by solid phase extraction (SPE) experimentation to generate two fractions: (F1) and (F2). HPLC-UV and HPLC-MS analysis showed that (F1) was made of known OMW monomeric phenolics mainly hydroxytyrosol (HT) while (F2) contained oligomeric and polymeric phenols such as verbascosid and ligstrosid. (HT) was purified from (F1) using silica gel-column chromatography and silica gel-TLC techniques. In incubated pancreas, supplementation of OMW fractions enhanced insulin secretion. The administration of OMW extract fractions (F1) and (F2) as well as purified (HT) in diabetic rats caused a decrease in glucose level in plasma and an increase in renal superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) activities in liver and kidney. Furthermore, a protective action against hepatic and renal toxicity in diabetic rats was clearly observed. Furthermore, a significant decrease in hepatic and renal indices toxicity was observed, i.e. alkalines phosphatases (ALP), aspartate and lactate transaminases (AST and ALT) activities and the thiobarbituric acid-reactive substances (TBARs), total and direct bilirubin, creatinine and urea levels. In addition, (F1), (F2) and especially (HT) decreased triglycerides (TG), total-cholesterol (T-Ch) and higher HDL-cholesterol (HDL-Ch) in serum. These beneficial effects of OMW biophenols were confirmed by histological findings in hepatic, renal and pancreatic tissues of diabetic rats. This study demonstrates for the first time that OMW polyphenols and especially (HT) are efficient in inhibiting hyperglycemia and oxidative stress induced by diabetes and suggests that administration of HT may be helpful in the prevention of diabetic complications associated with oxidative stress.

Inhibitory potential of omega-3 fatty and fenugreek essential oil on key enzymes of carbohydrate-digestion and hypertension in diabetes rats

Backgrounddiabetes is a serious health problem and a source of risk for numerous severe complications such as obesity and hypertension. Treatment of diabetes and its related diseases can be achieved by inhibiting key digestives enzymes-related to starch digestion secreted by pancreas.MethodsThe formulation omega-3 with fenugreek terpenenes was administrated to surviving diabetic rats. The inhibitory effects of this oil on rat pancreas α-amylase and maltase and plasma angiotensin-converting enzyme (ACE) were determined.Resultsthe findings revealed that administration of formulation omega-3 with fenugreek terpenenes (Om3/terp) considerably inhibited key enzymes-related to diabetes such as α-amylase activity by 46 and 52% and maltase activity by 37 and 35% respectively in pancreas and plasma. Moreover, the findings revealed that this supplement helped protect the β-Cells of the rats from death and damage. Interestingly, the formulation Om3/terp modulated key enzyme related to hypertension such as ACE by 37% in plasma and kidney. Moreover administration of fenugreek essential oil to surviving diabetic rats improved starch and glucose oral tolerance additively. Furthermore, the Om3/terp also decreased significantly the glucose, triglyceride (TG) and total-cholesterol (TC) and LDL-cholesterol (LDL-C) rates in the plasma and liver of diabetic rats and increased the HDL-Cholesterol (HDL-Ch) level, which helped maintain the homeostasis of blood lipid.Conclusionoverall, the findings of the current study indicate that this formulation Om3/terp exhibit attractive properties and can, therefore, be considered for future application in the development of anti-diabetic, anti-hypertensive and hypolipidemic foods.

Structural characterization and functional properties of antihypertensive Cymodocea nodosa sulfated polysaccharide.

A sulfated polysaccharide was successfully isolated from Cymodocea nodosa (CNSP). This is the first report that indicates the chemical composition, structural characterization, functional and antihypertensive properties of this polysaccharide. The CNSP consisted mainly of sulfate (23.17%), total sugars (54.90%), galactose (44.89%), mannose (17.30%), arabinose (12.05%), xylose (9.18%), maltose (1.07%) and uronic acid (11.03%) with low water activity (0.49). CNSP had an XRD pattern that was typical for a semi-crystalline polymer with homogeneous structure. It also displayed an important anti-hypertensive activity (IC50=0.43mgml) with a dose-dependent manner using a synthetic substrate, N-hippuryl-His-Leu hydrate salt (HHL). Overall, the results indicate that CNSP have attractive chemical, functional and biological properties, with a preliminary structural may have a backbone of branched 6-O-sulfated (1→4) galactosidic linkages, which can be considered in the future as alternative additive in various foods, cosmetic and pharmaceutical preparations.

Inhibitory Activities of Zygophyllum album: A Natural Weight-Lowering Plant on Key Enzymes in High-Fat Diet-Fed Rats

Obesity is a serious health problem that increased risk for many complications, including diabetes and cardiovascular disease. The results showed EZA, which found rich in flavonoids and phenolic compounds, exhibited an inhibitory activity on pancreatic lipase in vitro with IC50 of 91.07 μg/mL. In vivo administration of this extract to HFD-rats lowered body weight and serum leptin level; and inhibited lipase activity of obese rats by 37% leading to notable decrease of T-Ch, TGs and LDL-c levels accompanied with an increase in HDL-c concentration in serum and liver of EZA treated HFD-rats. Moreover, the findings revealed that EZA helped to protect liver tissue from the appearance of fatty cysts. Interestingly, supplementation of EZA modulated key enzyme related to hypertension such as ACE by 36% in serum of HFD animals and improve some of serum electrolytes such as Na+, K+, Cl−, Ca2+ and Mg2+. Moreover, EZA significantly protected the liver-kidney function by reverted back near to normal the values of the liver-kidney dysfunction indices AST&ALT, ALP, CPK and GGT activities, decreased T-Bili, creat, urea and uric acid rates. In conclusion, these results showed a strong antihypelipidemic effect of EZA which can delay the occurrence of dislipidemia and hypertension.

Inhibition of key enzymes related to diabetes and hypertension by Eugenol in vitro and in alloxan-induced diabetic rats

Abstract The present study investigated the effect of treating diabetic rats with eugenol (EG). In vitro enzyme activity was measured in the presence of eugenol, and it was found to inhibit pancreatic α-amylase (IC50 = 62.53 µg/mL) and lipase (IC50 = 72.34 µg/mL) as well as angiotensin converting enzyme (ACE) activity (IC50 = 130.67 µg/mL). In vivo, EG reduced the activity of amylase in serum, pancreas and intestine also the peak level of glucose by 60% compared to diabetic rats. Furthermore, eugenol similar to acarbose reduced serum glycosylated hemoglobin (HbA1c), lipase and ACE levels. In addition, treatments with EG showed notable decrease in serum total-cholesterol, triglycerides and low density lipoprotein-cholesterol levels with an increase of high density lipoprotein-cholesterol. Overall, EG significantly reverted back to near normal the values of the biochemical biomarkers such as transaminases (AST&ALT), alkaline phosphatase (ALP), creatine phosphokinase (CPK) and gamma-glutamyl transpeptidase (GGT) activities, total-bilirubin, creatinine, urea and uric acid rates.

In vitro anti-diabetic, anti-obesity and antioxidant proprieties of Juniperus phoenicea L. leaves from Tunisia

ABSTRACT Objective To examine chemical composition and antioxidant activity as well as the in vitro α-amylase and pancreatic lipase inhibitory activities of the essential oil and various extracts of Juniperus phoenicea ( J. phoenicea ). Methods Essential oil obtained by steam distillation were analyzed by gas chromatography-mass spectrometry technique. The antioxidant activity of the essential oil and various extracts of J. phoenicea were determined by DPPH and β-carotene bleaching methods. Results Gas chromatography-mass spectrometry analysis of the J. phoenicea essential oil resulted in the identification of 37 compounds, representing 96.98% of the oil; α-Pinene (24.02%), limonene (7.94%), D-3-Carene (16.9%), Germacrene D (11.98%), Germacrene B (5.40%) and δ-cadinene (6.52%) were the major compounds. The IC 50 values of essential oil, hexane and methanol extracts against α-amylase were 35.44, 30.15 and 53.76 μg/mL respectively, and those against pancreatic lipase were 66.15, 68.47 and 60.22 μg/mL respectively, suggesting powerful anti-diabetic and anti-obesity effects. Antioxidant activity (IC 50 =2 μg/mL) and total phenolics content (265 mg as gallic acid equivalent/g extract) of the methanol extract were found to be the highest compared to the other extracts. Conclusions The findings showed that the extents of α-amylase and pancreatic lipase inhibitory activities of the J. phoenicea extracts as well as their antioxidant activity are in accordance with total phenolics contents. Leaves of J. phoenicea being rich in phenolics may provide a good source of natural products with interesting medicinal properties.

Cytotoxic sesquiterpenoids from Winteraceae of Caledonian rainforest.

One secobutanolide, two butanolides and six drimane sesquiterpenoids were isolated from the bark and leaves of Zygogynum pancheri and Zygogynum acsmithii (Winteraceae) along with six known drimanes, isodrimanial, 1beta-O-p-methoxy-E-cinnamoyl-bemadienolide, 7-ketoisodrimenin, drimenin, polygodial and 1beta-E-cinnamoyl-6alpha-hydroxypolygodial. Their structures were elucidated through analysis of spectroscopic data. Drimane sesquiterpenoids with a dialdehyde function exhibited significant inhibitory activities in the in vitro cytotoxic assays against KB, HL60 and HCT116 cancer cell lines.

Biologically active tetralones from New Caledonian Zygogynum spp.

Bioassay guided purification of the ethyl acetate extracts of the bark and leaves of five New Caledonian Zygogynum species (Winteraceae) led to the isolation and characterization of four phenyl-3-tetralones (3,4-dihydronaphthalen-1(2H)-one). Their structures were determined by various NMR techniques and chemical studies. The absolute configuration of the compounds was established by circular dichroism. The compounds showed binding affinity for peroxisome proliferator-activated receptor-gamma (PPAR-gamma) and significant inhibitory activity against KB cancer cell line.

Assessment of anthropogenic inputs in the surface waters of the southern coastal area of Sfax during spring (Tunisia, Southern Mediterranean Sea)

The coastal marine area of Sfax (Tunisia), which is well-known for its high productivity and fisheries, is also subjected to anthropogenic inputs from diverse industrial, urban and agriculture activities. We investigated the spatial distribution of physical, chemical and biogeochemical parameters in the surface waters of the southern coastal area of Sfax. Pertinent tracers of anthropogenic inputs were identified. Twenty stations were sampled during March 2013 in the vicinity of the coastal areas reserved for waste discharge. Phosphogypsum wastes dumped close to the beaches were the main source of PO4(3-), Cl(-) and SO4(2-) in seawater. The high content in total polyphenolic compounds was due to the olive oil treatment waste water released from margins. These inorganic and organic inputs in the surface waters were associated with elevated COD. The BOD5/COD (<0.5) and COD/BOD5 (>3) ratios highlighted a chemical pollution with organic load of a low biodegradability.