Cell viability effects and antioxidant and antimicrobial activities of Tunisian date syrup (Rub El Tamer) polyphenolic extracts

The aqueous-acetone polyphenolic extract of the traditionally derived date syrup, known as "Rub El Tamer", was analyzed using RP-HPLC-DAD and ESI-MS. The phenolic content of the extract was 394.53 ± 1.13 mg per 100 g of syrup with caffeoylsinapylquinic acid as the most abundant compound (72.23%). The extract exhibited strong antioxidant activities as evaluated using the ABTS (2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid)), DPPH (2,2-diphenyl-1-picrylhydrazyl) and FRAP (ferric reducing antioxidant power) methods. The extract antimicrobial potential against a range of microorganism strains showed that Staphylococcus aureus, Staphylococcus epidermidis, and Bacillus cereus were the most sensitive bacteria with MBC in the range of 0.5-0.05 mg/mL. Furthermore, in the presence of the syrup extract (8.18-131 μg/mL), the Human SH-SY5Y neuroblastoma and the 3T3 fibroblast cell lines showed dissimilar reduction of viability suggesting a higher cytotoxic effect against tumorigenic cells. Our results provide new insights into date syrup characterization which should stimulate further studies of this hot desert resource.     

Genetic polymorphism of plastid DNA in Tunisian date-palm germplasm (Phoenix dactylifera L.) detected with PCR-RFLP

Fifteen plastid fragments were amplified from a set of Tunisian date-palm accessions by PCR with consensus primers and analysed by RFLP. Polymorphic DNA bands were obtained as reliable molecular markers to estimate genetic distances among the accessions and to examine their phylogenetic relationships. The ctDNA PCR-RFLP method permitted the identification of two haplotypes that differ in the presence or absence of the HinfI restriction site. Phenetic groups composed of cultivars clustered together but does not constitute monophyletic groups. This typology agrees with the haplotypes' organization and provides a common genetic background within the implied varieties.     

Composition of the essential oils of Thymus and Origanum species from Algeria and their antioxidant and antimicrobial activities

The composition of the essential oils of Origanum and Thymus species restricted to Algeria and the North Africa region was determined. Antioxidant and antibacterial activities of the isolated essential oils were also determined. The oils of oregano plants were strongly characterized by p-cymene (16.8-24.9%), gamma-terpinene (16.8-24.9%), thymol (8.4-36.0%), and carvacrol (1.1-29.7%), a thymol chemotype for Origanum floribundum and a alpha-terpineol chemotype for Thymus numidicus being described for the first time. The strains of Listeria monocytogenes tested were relatively resistant to the action of essential oils of either Origanum or Thymus species. All essential oils possessed antioxidant activity, but this was dependent on the specific chemical composition and the method employed to determine such activity.     

Aloe vera long-term saline irrigation increases contents of hydrogen peroxide,lipid peroxidation and phenolic compounds

Salt stress is more and more becoming a serious problem in the world especially if we consider its damaging effect on the plant growth and yield. The cultivation of medicinal plants, such as Aloe vera, might be an alternative for the saline water use and salt-affected soils occupation. Aloe vera, commonly known as aloe, is one of the primary medicinal plants with multipurpose applications going from pharmaceutical to cosmetic aspects with a promising economic return. Aloe plants were cultivated and irrigated, for 14 months, with drinking water (C0) and with two levels of salt (C1 and C2). Changes in growth, hydrogen peroxide (H₂O₂), lipid peroxidation and phenolic compounds were examined in leaves at harvest. Depressive effects of salt irrigation on the plant growth parameters and a perturbation in inorganic ion contents were found especially with a high level of salt in the irrigation water. The intracellular oxidative stress was evaluated with the H₂O₂ production. Our results showed that the H₂O₂ content increased with the accumulation of the toxic ion (Na) in the leaf tissues. In addition, lipid peroxidation, measured by the malondialdehyde (MDA) level, increased as well with salt augmentation in the irrigation water. In response to salt stress, Aloe leaves showed a significant increase in the levels of phenolic compounds too. These results suggest that Aloe can be planted in soils affected by salinity and irrigated with salt water at least at a moderate concentration used in the present study.     

Radical scavenging activity of black cumin (Nigella sativa L.), coriander (Coriandrum sativum L.), and niger (Guizotia abyssinica Cass.) crude seed oils and oil fractions

Crude vegetable oils are usually oxidatively more stable than the corresponding refined oils. Tocopherols, phospholipids (PL), phytosterols, and phenols are the most important natural antioxidants in crude oils. Processing of vegetable oils, moreover, could induce the formation of antioxidants. Black cumin (Nigella sativa L.), coriander (Coriandrum sativum L.), and niger (Guizotia abyssinica Cass.) crude seed oils were extracted with n-hexane and the oils were further fractionated into neutral lipids (NL), glycolipids (GL), and PL. Crude oils and their fractions were investigated for their radical scavenging activity (RSA) toward the stable galvinoxyl radical by electron spin resonance (ESR) spectrometry and toward 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical by spectrophotometric method. Coriander seed oil and its fractions exhibited the strongest RSA compared to black cumin and niger seed oils. The data correlated well with the total content of polyunsaturated fatty acids, unsaponifiables, and PL, as well as the initial peroxide values of crude oils. In overall ranking, RSA of oil fractions showed similar patterns wherein the PL exhibited greater activity to scavenge both free radicals followed by GL and NL, respectively. The positive relationship observed between the RSA of crude oils and their color intensity suggests the Maillard reaction products may have contributed to the RSA of seed oils and their polar fractions. The results demonstrate the importance of minor components in crude seed oils on their oxidative stability, which will reflect on their food value and shelf life. As part of the effort to assess the potential of these seed oils, the information is also of importance in processing and utilizing the crude oils and their byproducts.     

Soil carbon and nitrogen changes after clearing mulga (Acacia aneura) vegetation in Queensland,Australia: Observations,simulations and scenario analysis

In the work reported here we examine the changes in soil (organic) carbon and nitrogen that are observed after converting a stand of nitrogen-fixing mulga trees (Acacia aneura) to buffel-grass (Cenchrus ciliaris) pasture that contained no nitrogen-fixing legumes. A range of previously reported field measurements was compared against the output of CenW 3.1, a reformulated version of the CENTURY model.The model successfully reproduced the observed patterns of soil carbon, C:N ratios and nitrogen mineralisation rates under mulga vegetation. This included relatively small changes in carbon concentration down to 1 m, C:N ratios of around 11–13 across all soil depths, substantial nitrogen mineralisation rates to a depth of 90 cm and, after clearing, an on-going decrease in soil organic carbon and nitrogen stocks.Interpretation of experimental observations was made difficult by the addition of a large amount of ‘dead’ organic matter from killed mulga roots after clearance. This material may be excluded through sieving (to 2 mm) in measurements taken shortly after tree removal, but may be included in later-year sampling as the partly decomposed material might be able to pass through sieves. Past work has usually ignored consideration of dead coarse roots. For the site carbon budget, changes in live biomass and surface litter significantly outweighed the small changes in soil organic carbon, and changes in decaying coarse roots were quantitatively more important than changes in other organic carbon pools.Modelled nitrogen mineralisation rates were lower under buffel-grass than those under mulga and showed significant year-to-year variations that were in line with varying rainfall. It showed no consistent trend over the first 20 years after clearing because the effect of decreasing nitrogen stocks was balanced by an increase in organic matter quality with the change from lignin-rich mulga litter to buffel-grass litter with lower lignin concentration. Nitrogen mineralisation rates gradually decreased thereafter as nitrogen stocks continued to decrease but litter quality stabilised.A scenario analysis showed that soil carbon and nitrogen trends could be affected by changing the nitrogen budget through inclusion of legumes or cessation of nutrient removal by grazing animals. Inclusion of legumes was needed to halt the decline in soil nitrogen and to ensure the long-term maintenance, or increase, in nitrogen stocks.     

Studies on Normal Haematological and Serum Biochemical Values of the ‘Hijin’ Racing Camels (Camelus dromedarius) in Kuwait

Haematological estimations and serum biochemical analyses were made on 100 samples collected from clinically healthy Hijin racing camels (Camelus dromedarius) in Kuwait. The red blood cell counts, packed cell volume, haemoglobin concentration, mean corpuscular volume, mean corpuscular haemoglobin, mean corpuscular haemoglobin concentration and total white blood cell counts were estimated. In the serum biochemical analyses, sodium, potassium, iron, calcium, phosphorus, magnesium, total bilirubin, blood urea nitrogen, creatinine, glucose, total protein and cholesterol concentrations were measured, as were the alanine aminotransferase, aspartate aminotransferase, -glutamyltransferase, creatine kinase and alkaline phosphatase activities. The results are discussed in relation to other findings reported in camels.     

Percutaneous ultrasound-guided over-the-wire catheterization of the portal and hepatic vessels in cattle

A new method for catheterization of the portal and hepatic veins in cattle by means of the over-the-wire system was investigated to maintain more reliable long-term patency of catheters. Four cattle were used to evaluate the success rate, patency and safety of the procedure. The catheters, coated by urokinase were patent as long as they were in situ. In addition, the introducer was useful to prevent the catheter from being broken. No complications developed during the10 days after the procedure. Two cows were then euthanized. Post mortem findings were minimal. The results of the study reported here are promising, the benefits are significant and there is no apparent disadvantage to its use.