Mohamed K. Mahmoud-Aly

Olive Mill Wastewater (OMWW) is produced in large quantities and contains high levels of nutrients that can be reused for irrigation, reducing the demand for freshwater resources. However, OMWW is phytotoxic and expensive to treat, making it important to develop more cost-effective treatment methods. This study aims to investigate an integrated detoxification treatment sequence consisting of acid precipitation, Fenton oxidation, and electrical coagulation to safely reuse OMWW for barley germination. Raw, treated and diluted OMWW (25% and 50% OMWW) were tested. The results showed that raw and diluted OMWW suppressed seed germination at all concentrations, while diluted treated OMWW enhanced seed germination and plant growth. In addition, treated OMWW (acid precipitation treatment) at 25% dilution reported 0% phytotoxicity significantly improved plant growth, where plant fresh weight (FW) reached 123.33 mg. Moreover, α-amylase, lipase, and protease enzyme activity confirmed the superior enhancement of barley growth parameters, where the highest enzyme activity value recoded 0.870 mg maltose/g FW. The integrated treatments reduced detoxification by 97.90% for total phenolic, 98.37% for total flavonoids, and 99.18% for total tannins. Reductions of around 95.78%, 60.00%, and 78.90% in total organic carbon, electric conductivity, and total solids, respectively, were achieved. A significant decrease in heavy metals was observed with removal ratios 98.64%, 94.80%, 96.88%, and 95.72% for Fe, Cu, Mn, and Zn, respectively. Seedling Vigor Index as an indicator of crop productivity was successfully predicted using neural network modeling. Therefore, the applied method can be used as a fertilizer to support plant growth and reduce fertilization costs.

Biodiesel is commercially produced from edible lipids such as soybean, canola, and palm oils. Using edible lipids for biodiesel production increases the competition with food production leading to the “food versus fuel” debate. Therefore, alternative...

Chlamydomonas reinhardtii is a model organism for nutrient limitation studies and many other physiological studies. Phosphorus (P) limitation triggers the expression of many genes involved in P uptake and manipulation and implicates in photosynthesis activity alteration. Here, we physiologically characterize a knockout mutant of vacuolar transporter chaperon1 (Δvtc1) under P replete and deplete conditions comparing to its rescue strain. The growth rate of Δvtc1 strain was faster than that of VTC1 rescued strain under P repletion but much slower under P depletion. P starved Δvtc1 cells showed higher death ratio. VTC1 deletion may affect P uptake. Lastly, in Δvtc1 strain grown under P deplete condition, the lower cell density, the lower self-shading, the lower chlorophyll (chl) b content, the higher chl a/b ratio.

The location of major quantitative trait loci (QTL) contributing to stem and leaf [Na+] and [K+] was previously reported in chromosome 7 using two connected populations of recombinant inbred lines (RILs) of tomato. HKT1;1 and HKT1;2, two tomato Na+-selective class I-HKT transporters, were found to be closely linked, where the maximum logarithm of odds (LOD) score for these QTLs located. When a chromosome 7 linkage map based on 278 single-nucleotide polymorphisms (SNPs) was used, the maximum LOD score position was only 35kb from HKT1;1 and HKT1;2. Their expression patterns and phenotypic effects were further investigated in two near-isogenic lines (NILs): 157-14 (double homozygote for the cheesmaniae alleles) and 157-17 (double homozygote for the lycopersicum alleles). The expression pattern for the HKT1;1 and HKT1;2 alleles was complex, possibly because of differences in their promoter sequences. High salinity had very little effect on root dry and fresh weight and consequently on the plant dry weight of NIL 157-14 in comparison with 157-17. A significant difference between NILs was also found for [K+] and the [Na+]/[K+] ratio in leaf and stem but not for [Na+] arising a disagreement with the corresponding RIL population. Their association with leaf [Na+] and salt tolerance in tomato is also discussed. © 2012 Blackwell Publishing Ltd.