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Fusarium graminearum is among the most virulent pathogens attacking wheat plants and significantly lowering its production globally. The present work aims to shed light on the interactions between two priming solutions, calcium (Ca) or salicylic acid (SA), and F. graminearum inoculation depending on the growth rate, physiological attributes, and molecular responses in wheat seedlings. In a pot experiment, F. graminearum-pre-inoculated or inoculum-free sandy soil was used to germinate wheat kernels after priming them for 12 h in distilled water, 5-mM CaCl2, or 0.05-mM SA. The results demonstrated that F. graminearum inoculation decreased growth rate and chlorophyll content, but promoted carotenoids, stress markers (electrolytes leakage, lipid peroxidation, protein oxidation, hydrogen peroxide, and hydroxyl radical), antioxidant molecules (AsA, phenols, and flavonoids), osmolytes (GB, amino acids, and proline), and the antioxidant enzymes (CAT, GPX, SOD, PPO, and PAL). Additionally, the fungal infestation boosted the expression of CAT, GR, PR4, MT, and PCS genes. However, presoaking wheat kernels in Ca or SA solutions has contributed to mitigating the negative effects of fungal inoculation by restoring growth rate, chlorophyll content, and antioxidant capacity. It has also decreased the induced oxidative stress and downregulated the gene expression of F. graminearum-inoculated wheat seedlings. Consequently, by minimizing the negative repercussions of F. graminearum infestation, priming with Ca or SA could be used to appropriately stimulate growth and readjust the oxidative status of wheat seedlings.

Synthetic fertilizers are widely employed in agriculture relative to biofertilizers. Long-term use affects soil fertility, plant vigor, human and livestock health, and the soil microbial community. Seaweeds were employed as biofertilizers in sustainable agriculture to overcome this issue and boost the agricultural productivity. Therefore, the current study investigates the effect of wheat seeds priming with the aqueous extracts of Ulva linza or Corallina officinalis seaweeds at various concentrations (5, 10, 15, 20, and 30%). Wheat grains were primed with seaweed extracts and grown in petri dishes, and the germination rate, growth attributes, physiological parameters, cytological traits, and molecular analyses were evaluated. The physico-chemical characterization revealed that U. linza possessed higher levels of ash, soluble proteins, and sugars, as well as essential macronutrients and amino acids, than C. officinalis. Seedling growth parameters, physiological characteristics, and mitotic index all showed a substantial increase in low concentrations of both extracts when compared to the control. Higher concentrations, on the other hand, exhibited an inhibitory effect as well as certain chromosomal abnormalities. In the treated seedlings, new proteins were expressed, which could be owing to the activity of bioactive components in the extracts. As compared to untreated seedlings, PCR-RAPD analysis utilizing five markers revealed that both seaweed extracts triggered low and high molecular weight DNA fragments, as well as fragments specific to each extract. Seaweed extracts could be employed as an environmentally friendly and soil-safe alternative to typical chemical fertilizers.

Root rot and head blight caused by soil-borne fungi are prevalent diseases endanger the global food security. The purpose of this study is to provide insight into the interaction of Fusarium graminearum with two weed extracts, concentrating on growth rate, physiological responses, molecular changes in wheat seedlings and yield parameters. In a pot experiment, wheat grains pre-soaked for 12 h either in distilled water or 25% aqueous weed extracts (purslane or chard) were germinated either in free or F. graminearum pre-inoculated sandy soil. The results revealed that F. graminearum inoculation resulted in reduced growth rate and chlorophyll content in wheat seedlings. However, following the fungal invasion, carotenoids, stress markers (EL, MDA, C = O, OH˙ and H2O2), non-enzymatic antioxidants (ascorbate and flavonoids), osmoregulators (GB, proline and free amino acids), antioxidant enzymes activity (CAT, POX, SOD and PPO) and the expression of some stress-induced genes (CAT, GR and PR4) were substantially increased. Nevertheless, priming of wheat grains with purslane or chard extracts resulted in enhanced growth rate, balanced chlorophyll content, decreased stress symptoms, restoration of the normal level of osmoregulators and antioxidant enzymes activity, as well as down-regulation of stress-induced genes in F. graminearum-infected wheat seedlings, besides improving yield characteristics. However, PR2 gene expression was not affected by either fungal infection or weed priming. In conclusion, natural weed extracts as supplement to chemical antifungals, can be safely employed to increase the growth rate and reconfigure the pathophysiological status of wheat seedlings by reducing the detrimental effects of F. graminearum infection.

Seaweeds are a viable bioresource for suffering plants against salt stress. The alleviating capacity of extracts from three brown algae (Sargassum vulgare, Colpomenia sinuosa, and Pandia pavonica) in pea (Pisum sativum L.) was investigated in this study. Pea seeds were primed for 2 h either with seaweed extracts (SWEs) or distlled water. Seeds were then subjected to salinity levels of 0.0, 50, 100, and 150 mM NaCl. On 21st day seedlings were harvested for growth, physiological and molecular investigations. SWEs were helpful in reducing the adverse effects of salinity on pea, with S. vulgare extract being the most effective. Furthermore, SWEs diminished the effect of NaCl-salinity on germination, growth rate, pigments content and raised the osmolytes proline and glycine betaine levels. On the molecular level, two low-molecular weight proteins were newly synthesized by the NaCl treatments and three by priming of pea seeds with SWEs. The number of inter-simple sequence repeats (ISSR) markers substantially increased from 20 in the control seedlings to 36 in 150 mM NaCl-treated seedlings, including four unique markers. Priming with seaweed extract triggered more markers than the control, however about ten of the salinity-induced markers were not detected following seed priming before NaCl treatments. By priming with SWEs, seven unique markers were elicited. All in all, priming with SWEs alleviated salinity stress on pea seedlings. The response of plants to salt stress and priming with SWEs is reflected by the synthesis of salinity responsive proteins and ISSR markers.

Phlomis aurea Decne. and Phlomis floccosa D. Don. exhibit different ecological and geographical distribution range in Egypt. Phlomis aurea is endemic to Saint Katherine Protectorate (SKP), South Sinai with narrow geographic distribution, but wide ecological range. Phlomis floccosa has wide geographical and ecological range within the coastal western Mediterranean coast of Egypt. Unlike P. floccosa, P. aurea has wide altitudinal range which increases its resistance to climate changes. Here, we assessed the effect of microhabitats on growth parameters and plant vigor of P. aurea and P. floccosa. The maximum EC of the soil in the various microhabitats supporting P. floccosa (950 µS/cm) is substantially higher than that of P. aurea (110 µS/cm). Both Phlomis species had low number of associated species which may be related to habitat aridity. The results indicate that the microhabitats supporting both species are the best environments for future conservation of these species under the impact of climate change.

Salinity is a critical issue impairing the growth and productivity of most crop species through the mediated ionic and osmotic imbalances. As a way forward, the current study was tailored to elucidate the capacity of sulfur nanoparticles (SNPs) to amend salinity consequences on growth and physio-biochemical attributes of wheat. In a controlled experiment, wheat seeds were primed for 12 h with either 100 μM SNPs or deionized water then sown in plastic pots containing 5 kg clay-sand mixture (2:1 w/w). A week later, pots received NaCl (100 or 200 mM) as a sole treatment or in combination with SNPs and after three weeks the data of morph-bio-physiological traits were recorded. Salinity decreased growth rate, pigmentation, protein, amino acids, cysteine, ascorbate, flavonoids and phenolics content in wheat leaves. Plants pre-treated with 100 μM SNPs showed improved growth rate, pigmentation, nitrogen metabolism as well as non-enzymatic antioxidant contents as compared with salinized treatments. Neither salt nor SNP treatments affected photosynthetic performance rate (Fv/fm), however both treatments induced glutathione content. SNP treatment retrieved the undue excessive activities of catalase (CAT), peroxidase (POD), ascorbate peroxidase (APX), superoxide dismutase (SOD) and polyphenol oxidase (PPO) besides the increased level of proline caused by salt stress. Likewise, 100 μM SNPs rebalanced the declined nitrogen, phosphorus and potassium contents and decreased sodium uptake caused by salinity. On the whole, priming with 100 μM SNPs improved photosynthetic pigments, nitrogen metabolism, antioxidant status and ionic relations contributing to the enhancement of growth attributes in wheat under salinity.

Controlled-release urea fertilizer (CRUF) consists of urea granules intercalated within the lattice of a superabsorbent composite to control urea release thereby improving nitrogen supply and minimizing environmental hazards. In this work, new formulations for controlled-release urea were prepared based on biodegradable polymers and agricultural waste. Following CRUF preparation, the release behavior of urea in aqueous medium was estimated, and the effect of medium pH on release behavior was also examined. A pot experiment was carried out on rice plants to examine the growth, yield performance and physio-biochemical traits (soluble proteins, amino acids, reducing and total free sugars, starch, proline and phenolics) of rice grains at different dosages (10, 25, 50, 75 and 100 kg ha−1) of CRUF under drought conditions (50% FC). Water stress adversely affected rice growth, membrane leakage and yield components (tiller length, filling ratio, grains mass and number per tiller). Drought exposure has influenced the physiological response of rice grains. Drought markedly increased proteins, amino acids, reducing and total free sugars and proline, but decreased starch and phenolic contents of rice grains. The application of CRUF mitigated water stress via improving the growth and yield parameters of rice plants. CRUF significantly decreased protein, amino acids, reducing sugars and proline contents but remarkably increased free sugars and starch contents of rice grains. Application of CRUF predominantly enhanced water and nutrients use efficiencies, contributing to improved metabolic machinery of droughted rice through reducing osmotic and oxidative stress levels by continued rhizophore moistening, extended urea nitrogen existence and enhanced soil characteristics.

Increased urbanization detrimentally affects crop plants. Heavy metals pollution sharply threatens food security. However, greenly synthesized nanoparticles were recently proposed as growth bioregulators. To investigate the evolved mechanisms by which sulfur nanoparticles (SNPs) could improve cellular defense against manganese toxicity, the present experiment was applied on Helianthus annuus (L.) seedlings. The experimental design was based on priming of sunflower seeds for 18 h in different (12.5–200 μM) SNPs, while 100 mM manganese sulfate (MnSO4) was implemented as irrigation treatment. The 14-day-old seedlings manifested Mn noxiousness and oxidative stress indications such as increased reactive oxygen species (O2·− and H2O2) and lipid peroxidation. Manganese exposure severely lowered the activity of some antioxidant enzymes like superoxide dismutase (SOD) and catalase (CAT), while induced ascorbate peroxidase (APX), guaiacol peroxidase (POX), polyphenol oxidase (PPO), and glutathione reductase (GR) activities. An evident decline in the pool of antioxidant compounds, such as ascorbic acid (ASA), glutathione (GSH), and total flavonoids content (TFC), was attained with Mn stress. Priming with SNPs significantly stimulated CAT and SOD activities and enhanced the antioxidant compounds (ASA, TFC, and total phenolic compounds) level in Mn-stressed seedlings. Consequently, SNPs caused a significant decrease in O2·−, H2O2, and lipid peroxidation and their oxidative damage. However, a significant reduction in GSH was detected with SNPs that might be consumed and incorporated into biosynthesis of other chelating ligands. Therefore, SNPs manifested a vital role in Mn detoxification through counterbalancing oxidative damage and elevating the antioxidant defense machinery.

Salinization of the agricultural soil, caused by natural factors or human activities, is one of the greatest challenges facing food production in the current time, as it negatively affects soil construction along with growth and yield of crops. In this study, an experiment was conducted on mallow plants (Corchorus olitorius L.) growing in pots to determine the effect of Na2SO4 stress on growth, physio-biochemical attributes, as well as antioxidative response, and the effect of parsley extract on salinity stress. Treatments consisted of 100 mM Na2SO4 and 10% parsley extract as single or combined treatments. Na2SO4 stress significantly reduced the plant growth, photosynthetic pigments, amino acids, glycinebetaine (GB), tannins, glutathione reductase (GR), ascorbic acid (AsA), and DPPH activity, while it significantly increased soluble sugars, proteins, proline, malondialdehyde (MDA), phenolics, catalase (CAT), superoxide dismutase (SOD), glutathione S-transferase (GST), reduced glutathione (GSH), total antioxidant activity (via phosphomolybdate assay (PMA)) and reducing power activity (RPA). Pre-soaking of mallow seeds in parsley extract enhanced growth, pigments, phenolics, tannins, CAT, GST, DPPH and RPA compared to salt-stressed plants. Integrative treatments of parsley with Na2SO4 remarkably increased growth, pigments, sugars, GR, GST, DPPH and RPA of stressed plants, but these treatments declined proteins, amino acids, proline, GB, lipid peroxidation (MDA), tannins, CAT, SOD and GSH in stressed mallow plants. Moreover, priming with parsley extract restored the ionic homeostasis in salt-stressed mallow. The results of this study recommend pre-soaking of mallow seeds in parsley extract to confer mallow growth in moderate saline soils.

A range of heterogeneous, inexpensive and benign Schiff bases-montmorillonite composites were synthesized and screened for their antibacterial activity against common microbial pathogens. Sodium montmorillonite (Na-MMT) clay was modified with tris(2-ethylamine) in the presence of dilute HCl to yield a quaternary salt of tris(2-ethylamine) modified clay. The Schiff bases were then fabricated from the reaction of the modified montmorillonite using different aldehydes. The structures of the obtained compounds were confirmed by Fourier transformer Infrared (FT-IR), X-ray diffraction (XRD), and thermal gravimetric analysis (TGA). All the obtained composite materials were screened for their antibacterial activities against the multi-drug resistant (MDR) strains. It was reasoned that the modified MMT-based composites has the ability to absorb the different micro-organisms onto the surface, and accordingly act as an effective antibacterial agent. All the composites showed significant antibacterial activity between 2.5 and 20 mg/mL against the MDR bacterial strains. The benzyl-based/modified MMT and the tertiary amino-based/modified MMT was found to be the most effective antibacterial agent. Keywords: Organoclay, Antibacterial composite, Montmorillonite, Tris(2-ethylamine)

A pot experiment was conducted to evaluate the capacity of superabsorbent composite (SAP) Gelatin-g-p(AA-co-AM)/RH to improve the performance of rice, maize, and peanut against terminal water stres...

Plants offer unlimited source of bioactive compounds that have tremendous applications in pharmaceutical industry. To find new sources of antioxidants and antimicrobial agents against pan-drug resistant (PDR) pathogens of skin burn infections, methanolic extracts of nine Egyptian plants were evaluated. Total phenolic content varied from 19.48 to 65.48 mg GAE/g dry weight (dw). Total flavonoid content varied from 2.90 to 11.09 mg QE/g dw, while total alkaloid content varied from 18 to 60 mg/g dw. Suaeda vermiculata, Varthemia candicans and Arthrocnemum glaucum showed the highest content of phenolics, flavonoids and alkaloids, respectively. The results of antioxidant (DPPH assay) activity were varied to a great extent and Varthemia candicans (90.6%) and Suaeda vermiculata (90.5%) showed the highest antioxidant activities. Antimicrobial activity was assessed against four PDR bacterial and fungal strains; namely Staphylococcus aureus, Klebsiella pneumoniae, Candida albicans and Aspergillus flavus. Among all examined extracts, Salsola vermiculata and Suaeda vermiculata showed significant antimicrobial activity. The fatty acid composition of Salsola vermiculata and Suaeda vermiculata leaf extracts was detected using GC–MS analysis. Overall, Salsola vermiculata and Suaeda vermiculata could be used as an alternative source for the exploration of new antioxidant and antimicrobial agents that are potentially valued for food and biomedical applications.

Due to its substantial nutritional value, quinoa (Chenopodium quinoa Willd.) is currently attracting worldwide attention. Quinoa is characterized by a high adaptability to various environmental conditions. This is the first report on the phytochemical and genetic evaluation of quinoa germplasms introduced to Egypt, and the results could be used to implement propagation techniques in the future. For phytochemical characterization, 41 traits, including primary and secondary metabolites, antioxidant molecules, sugars, organic acids and fatty acids, were evaluated. At the same time, 4 RAPD and 7 ISSR markers were used for genetic analysis. UPGMA analysis of RAPD and ISSR polymorphic markers, their combined dataset and phytochemical traits were used to evaluate genetic relationships among genotypes. The quinoa genotypes displayed reasonable variation in the studied phytochemical traits. The results of the genetic analysis confirmed that RAPD and ISSR markers could be used to distinguish effectively quinoa genotypes. The phytochemical and genetic characterization reported herein will be a promising guide for breeding seed quality in quinoa.

A pots experiment was conducted in the greenhouse of Botany Department, Faculty of Science, TantaUniversity, Gharbiya governorate during the winter season 2015-2016 to study the response of salt-stressed safflower to extracts of two types of naturally growing costal halophytes, Z. album and H. strobilaceum. Safflower seeds were presoaked either in distilled water or 1% halophytic extract for 24 hrs then sown in plastic pots containing 2:1 w/w clay sandy soil according to the Randomized Complete Block Design until reaching the preflowering stage. After the initiation of cotyledonary leaves, seedlings were divided into two main groups: the first was treated with 1% halophytic extracts as presoaking (pre-treatment) or foliar spray application (post-treatment), while the second was specific for control treatments. Each of which was then divided into two subgroups; unstressed and stressed. Results showed that salt stress imposed negative consequences on growth and metabolic properties of safflower, whereas the extracts have helped the plant to adjust and enhance its performance under salt stress through induction of osmoprotectants, redox homeostasis and membrane integrity.

Floral preservative biocides in most cases consider toxic at the affective concentration to both plant and microbial proliferation. Therefore, in order to find nontoxic biocide, this experiment was conducted to evaluate a recent Synthetized Zirconyl Complex as a potential floral preservative biocide for cut roses (Rosa hybrida L. cv. Grand Prix). To assess the effect of Zirconyl biocide as potential preservative, cut roses was treated with 0, 10, 20 and 50 ppm plus 20% sucrose as pulse solution for 24 hours before transferred into holding solution 10 times dilution from the pulsing solution. The flower quality such as the vase life, flowers relative fresh weight and maximum flower diameter were observed. Also, flower water relation parameters were determined, besides evaluating the biochemical responses such as chlorophyll degradation and florescence, total soluble sugars, free amino acids, DPPH free radical scavenging activity, total phenolic compounds and total flavonoids were determined. Results indicated the possibility to use Zirconyl complex biocide as floral preservative at 20-50 ppm concentration to extend the cut rose flowers vase life of from 8.88 to 13 day through improving flower water relation parameters and reducing oxidative damage.

A novel green approach was utilized to fabricate sulfur nanoparticles (SNPs) with the aid of Ocimum basilicum leaves extract. The effective formation of the synthesized SNPs was examined and approved using UV–visible spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM), and Fourier transform infrared (FT-IR) spectroscopy. The average particle size was 23 nm with spherical shape and crystalline in nature. In the pot experiment, the synthesized SNPs were applied with different concentrations (12.5, 25, 50, 100 and 200 μM) as pre-soaking to Helianthus annuus seeds and irrigated with 100 mM MnSO4. As a result of manganese (Mn) exposure, the harvested 14-day sunflower seedlings showed a significant decline in the growth parameters (shoot length, leaf area and the relative water content of both shoot and root), photosynthetic pigments, mineral content (N, P, K, Ca, and Mg), and protein content compared to the control. The root length, electrolyte leakage, Na and Mn levels, metabolites content (amino acids, protein, glycine betaine, proline, and cysteine) were greatly raised as affected by Mn stress. Mn toxicity reduction using SNPs was demonstrated, as the medium doses enhanced seedlings growth, photosynthetic pigments, and mineral nutrients. Application of SNPs decreased Mn uptake and enhanced S metabolism through increasing cysteine level. Likewise, SNPs elevated seedlings water content and eliminated physiological drought via increasing osmolytes such as amino acids and proline. It can be concluded that green-synthesized SNPs had the potential to limit the deleterious effects of Mn stress.

Six varieties of soybean (Glycine max L.) plants were grown for 30 days under three levels of sea salt salinity (0.0, 8.0 and 16.0 mS/cm2) for studying the effect of sea salt on uptake of nitrate and response of the antioxidant system for these salinity doses. Salt treatments resulted in a gradual decline in nitrate uptake by increasing sea salt concentration, which mean that this will bring negative consequences on nitrogen assimilation. However, salt treatments induced the accumulation of hydrogen peroxide and glycinebetaine in the leaves of all soybean verities as an adaptive strategy to cope with salt stress. On the other hand, there was a differential response in phenolic compounds among soybean verities as a function of salt concentration and the studied variety, which means there has a decline in phenolics under salt stress in the varieties Crawford, G21, G22 and G83, but in contrary in G35 and G82, phenolics has accumulated in response to salinity. Isozymes electrophoretic banding showed changes in peroxidase activity with sea salt, however superoxide dismutase showed stability in number and intensity of bands with salt treatments. Esterase enzyme was more sensitive to salinity and showed a gradual decline in activity by increasing salt concentration.

Depletion of fossil fuels and increasing the environmental concerns against pollution accelerate the research in renewable energy with much efforts directed for the production of biodiesel by the promising oil-rich biomass, like oleaginous fungi, growing on inexpensive agricultural and industrial wastes. Rhizopus stolonifer was found to be the most potent lipid producer among the tested fungi in the present study; its growth was optimized at pH=6, glucose as C-source, NaNO3 as N-source, with agitation rate of 120 rpm, incubation temperature of 28 C after 6 days growth; which gave an observable lipid content of 57.9% dry wt. on non-detoxified liquid hydrolysate (NDLH) medium with saturated aliphatic long chains as revealed by GC-MS analysis. R. stolonifer gave noticeable activity of released sugar consumption (92.2%) on flax straw as a row material higher than rice, wheat straws and orange peel, forming high lipid content (54.33%) on flax; that was transesterified into biodiesel with cetane number of 61.48, that was higher than cetane number of the standard non-processed liquid diesel (< 47). So R. stolonifer can be considered as a good lipid producer on the depolymerized flax straw as a cheap source for biodiesel production.

This paper deals with an efficient synthesis of some 2-amino-5-substituted phenyl-1,3,4-oxadiazoles by using both conventional and microwave methods for chemotherapeutic use. The obtained results confirmed that, microwave assisted technique is efficient, eco-friendly, and inexpensive method which not only gives higher yield but also reduces the reaction time significantly. The structural elucidation of the prepared compounds was carried out by the aid of IR, 1 H NMR, UV-Vis and mass spectral analyses. Compounds S a -S f showed antimicrobial activities against Escherichia coli , Serratia marcescens, Salmonella enterica and Proteus vulgaris (Gram-negative bacteria) and Bacillus subtilis and Staphylococcus aureus (Gram-positive bacteria) at low concentrations (10–1000 µg/mL).

Depletion of fossil fuel is the largest challenge facing human industrial and technological revolution in the current era. Exploration of widely distributed microorganisms for the production of renewable biofuel is the most priority for scientific research in the last decades. In this context, thirteen fungal isolates were collected from Tanta city, El-Gharbia Governorate, Egypt belonging to four genera (Aspergillus, Penicillium, Fusarium and Alternaria) were screened on minimal media for their ability to accumulate lipid in their biomass. The maximum lipid contents were 25.31% for Aspergillus versicolor and 20.15% for Aspergillus niveus. The optimization result showed that pH 4, incubation temperature 32°C, sucrose at concentration of 40g/L, glutamic acid at concentration of 0.5 g/L (C/N ratio at 40:0.5 w/w) after 5 days of incubation with agitation rate of 150 rpm on orbital shaker were the most appropriate conditions for the highest lipid accumulation in the case of Aspergillus versicolor. However, in case of Aspergillus niveus, pH 4, incubation temperature at 32°C, sucrose at concentration of 20 g/L, NaNO3 at concentration of 1.0 g/L (C/N ratio at 20:1.0 w/w) after 11 days of incubation with agitation rate of 150 rpm were the most appropriate for the highest lipid accumulation.

Soil contamination with lead (Pb) represents a common heavy metal stress for cultivated plants. In the current study, effects of Pb stress on wheat (Triticum aestivum) plants were evaluated, and alleviating roles of purslane and chard natural weed extracts were assessed. The results showed that Pb treatment (100 mM) significantly reduced the growth of wheat seedlings and diminished plant yield parameters. Moreover, Pb stress inhibited photosynthetic activity measured as Fv/Fm. The levels of various stress markers increased under Pb stress as was verified by the increased electrolyte leakage, malondialdehyde (MDA) content, H2O2 and .OH radical content. Pb stress increased the activity of peroxidase (POX), catalase (CAT), superoxide dismutase (SOD), as well as raised the content of the antioxidant compound ascorbic acid. A remarkable induction in some genes was reported under Pb stress. The ameliorative role achieved by seed priming of wheat in purslane and chard weed extracts was demonstrated by the increase in growth parameters in seedling and yield stages. In the meantime, the priming treatments increased the Fv/Fm value. In addition, the activities of the antioxidant enzymes POX, CAT and SOD were reduced by seed priming. Data presented in the current work provide strong evidence that natural weed extracts are efficient to alleviate damaging effects of abiotic challenges such as heavy metal stress imposed by high soil Pb concentrations, and thus possibly could represent a valuable ecofriendly and commercial values for plant farmers.

New antibacterial composites were synthesized by modification and functionalization of montmorillonite (MMT). The antibacterial composites were synthesized by the reaction of MMT clay with the quaternary salt of p-N,N-dimethylamino benzaldehyde which produced modified functionalized montmorillonite composite in the form of Schiff bases. The Schiff bases (4–11) were obtained by the reaction of functionalized montmorillonite with various amines namely o-anisidine, anthranilic acid, p-carboxy aniline, p-methyl aniline, p-methoxy aniline, p-hydroxy aniline, p-nitro aniline and p-phenylene diamine. The structures of the newly prepared composites were elucidated by Fourier transform infra red (FT-IR), thermal gravimetric analysis (TGA) and X-ray diffraction (XRD). The antibacterial activities of these composites were investigated by the ‘cut plug’ method against Gram-negative bacteria such as Escherichia coli, Serratia marcescens, Enterobacter cloacae, Shigella dysenteriae, Salmonella enterica and Proteus vulgaris, and Gram-positive such as Bacillus subtilis and Staphylococcus aureus which showed high antimicrobial activities at relatively low concentrations (2.5–20 mg/mL). These promising results pave the way in the future to use the newly synthesized composites as antibacterial agents for water treatment against pathogenic bacteria which exist in polluted water courses. Keywords: Antimicrobial activities, Montmorillonite, p-N,N-dimethylamino benzaldehyde, Water treatment, Schiff bases

The oleaginous yeast Rhodotorula minuta has been used previously as a biocide agent and for the production of β-carotene. In addition, R. minuta has been shown to produce up to 40% lipids, while demonstrating a faster growth rate than the similar oleaginous yeasts; Lipomyces starkeyii and Rhodotorula glutinis. In this study this promising yeast was evaluated for its potential to produce glyceride lipids under the harsh conditions and complex sugar mixtures produced from depolymerised lignocellulose. The fatty acid profile of R. minuta was not found to change significantly irrespective of the environmental conditions and contained approximately 20% palmitic acid, 5% stearic acid, 60% oleic acid and 15% linolenic acid. R. minuta was found to grow on a range of sugars, and could consume xylose and glucose when both sugars were present, however, R. minuta was found to be highly sensitive to inhibitors, such as furfurals and organic acids, formed under the harsh lignocellulose depolymerisation conditions. Accordingly R. minuta did not grow well on biomass depolymerised with an acid pre-treatment stage. However, R. minuta was cultured successfully on food waste depolymerised with no additional acids, producing up to 19 g /L cell mass with a lipid content of up to 25% of the dry cell weight.

A novel series of α-aminophosphonates containing chitosan moiety was obtained in high yields from reactions of chitosan with aromatic aldehydes and triphenylphosphite in the presence of lithium perchlorate as a catalyst. The structures of the synthesized compounds were confirmed by IR and 1 H NMR spectral data. Compounds ( 1 – 4 ) showed high antimicrobial activities against Escherichia coli (NCIM2065), Serratia marcescens , Enterobacter cloacae , Shigella dysenteriae , Salmonella enterica and Proteus vulgaris as Gram-negative bacteria, Bacillus subtilis (PC1219) and Staphylococcus aureus (ATCC25292) as Gram-positive bacteria and Candida albicans as a fungus, at low concentrations (2.5–10 mg/mL).