Chemical Profile, Cytotoxic Activity and Oxidative Stress Reduction of Different Syringa vulgaris L. Extracts.

Syringa vulgaris L. (common lilac) is one of the most popular ornamental species, but also a promising not comprehensively studied source of bioactive compounds with important therapeutic potential. Our study was designed to characterize the chemical composition and to assess the antioxidant and cytotoxic properties of ethanolic extracts obtained from S. vulgaris L. flowers, leaves, bark, and fruit. The chemical profile of the ethanolic extracts was investigated using chromatographic (HPLC-DAD-ESI+, GC-MS) and spectral (UV-Vis, FT-IR) methods, while the protective effect against free radicals was evaluated in vitro by different chemical assays (DPPH, FRAP, CUPRAC). The cytotoxic activity was tested on two tumoral cell lines, HeLa, B16F10, using the MTT assay. Significant amounts of free or glycosylated chemical components belonging to various therapeutically important structural classes, such as phenyl-propanoids (syringin, acteoside, echinacoside), flavonoids (quercetin, kaempferol derivatives) and secoiridoids (secologanoside, oleuropein, 10-hydroxy oleuropein, demethyloleuropein, syringalactone A, nuzhenide, lingstroside) were obtained for the flowers, leaves and bark extracts, respectively. Furthermore, MTT tests pointed out a significant cytotoxic potential expressed in a non-dose-dependent manner toward the tumoral lines. The performed methods underlined that S. vulgaris extracts, in particular belonging to flowers and leaves, represent valuable sources of compounds with antioxidant and antitumoral potential.

Chemical and sensorial characterization of spray dried hydroSOStainable almond milk.

BACKGROUND: Water scarcity is a worldwide problem that leads to environmental and economic issues. Agriculture is one of the main consumers of water for irrigation and fertilization and almond is the major tree nut crop in the Mediterranean area. Furthermore, there is a continuous growing demand for healthy, vegan and sustainable products. Consequently, the present study aimed to chemically characterize almond milk powder enriched with probiotics manufactured from hydroSOStainable almonds (i.e. generated under water stress conditions). Almond milk powder enriched with probiotic bacteria was produced with almonds grown under optimal irrigation conditions (100% of the crop evapotranspiration) and was chemically compared to the samples made from hydroSOStainable almonds. Antioxidant activity, total phenolic content (TPC), minerals, organic acids and sugars, fatty acids, and descriptive sensory analysis were evaluated. RESULTS: The results showed that almond milk powder produced from hydroSOStainable almonds had a higher content of TPC, polyunsaturated fatty acids (PUFAs), PUFAs/saturated fatty acids (SFAs) ratio and PUFAs/monounsaturated fatty acids ratio, as well as almond and nutty flavors. Moderate and sustained deficit irrigation leads to powders with a higher content of PUFAs and PUFAs/SFAs ratio, which are parameters of utmost importance for health. CONCLUSION: Using these strategies, between 66% and 76% of the irrigation water can be saved, producing hydroSOStainable almond milk powder higher in TPC and PUFAs, as well as positive sensory attributes, compared to that from fully irrigated almonds. These findings may have a positive impact in both agriculture and food industry, allowing water savings and high quality and sustainable food products to be obtained. © 2020 Society of Chemical Industry.

Nutrient and Sensory Metabolites Profiling of Averrhoa Carambola L. (Starfruit) in the Context of Its Origin and Ripening Stage by GC/MS and Chemometric Analysis.

Averrhoa carambola L. is a tropical tree with edible fruit that grows at different climatic conditions. Despite its nutritive value and reported health benefits, it is a controversial fruit owing to its rich oxalate content. The present study aimed at investigating aroma and nutrient primary metabolites distribution in A. carambola fruits grown in Indonesia, Malaysia (its endemic origin) versus Egypt, and at different ripening stages. Two techniques were employed to assess volatile and non-volatile metabolites including headspace solid-phase micro-extraction (HS-SPME) joined with gas chromatography coupled with mass-spectrometry (GC-MS) and GC-MS post silylation, respectively. Twenty-four volatiles were detected, with esters amounting for the major class of volatiles in Egyptian fruit at ca. 66%, with methyl caproate as the major component, distinguishing it from other origins. In contrast, aldehydes predominated tropically grown fruits with the ether myristicin found exclusively in these. Primary metabolites profiling led to the identification of 117 metabolites viz. sugars, polyols and organic acids. Fructose (38-48%) and glucose (21-25%) predominated sugar compositions in ripe fruits, whereas sorbitol was the major sugar alcohol (2.4-10.5%) in ripe fruits as well. Oxalic acid, an anti-nutrient with potential health risks, was the major organic acid detected in all the studied fruits (1.7-2.7%), except the Malaysian one (0.07%). It increases upon fruit ripening, including considerable amounts of volatile oxalate esters detected via SPME, and which must not be omitted in total oxalate determinations for safety assessments.

Novel 2,4-Disubstituted-1,3-Thiazole Derivatives: Synthesis, Anti-Candida Activity Evaluation and Interaction with Bovine Serum Albumine.

Herein we report the synthesis of two novel series of 1,3-thiazole derivatives having a lipophilic C4-substituent on account of the increasing need for novel and versatile antifungal drugs for the treatment of resistant Candida sp.-based infections. Following their structural characterization, the anti-Candida activity was evaluated in vitro while using the broth microdilution method. Three compounds exhibited lower Minimum Inhibitory Concentration (MIC) values when compared to fluconazole, being used as the reference antifungal drug. An in silico molecular docking study was subsequently carried out in order to gain more insight into the antifungal mechanism of action, while using lanosterol-C14α-demethylase as the target enzyme. Fluorescence microscopy was employed to further investigate the cellular target of the most promising molecule, with the obtained results confirming its damaging effect towards the fungal cell membrane integrity. Finally, the distribution and the pharmacological potential in vivo of the novel thiazole derivatives was investigated through the study of their binding interaction with bovine serum albumin, while using fluorescence spectroscopy.

Hydroxycinnamic acids and human health: recent advances.

There is an urgent need to improve human diet globally. Compelling evidence gathered over the past several decades suggests that a suboptimal diet is associated with many chronic diseases and may be responsible for more deaths than any other risks worldwide. The main components in our diet that need higher intake are whole grains, fruit and vegetables, and nuts and seeds; all of these are important sources of dietary fiber and polyphenols. The health benefits of dietary fiber and polyphenols are also supported by several decades of valuable research. However, the conclusions drawn from interventional human trials are not straightforward and the action mechanisms in improving human health are not fully understood. Moreover, there is a great inter-individual variation caused by different individual capabilities of processing, absorbing and using these compounds effectively. Data on the bioavailability and bioefficacy of hydroxycinnamic acids (HCAs) are limited when compared to other classes of polyphenols (e.g. anthocyanins). This review aims to summarize the latest research advances related to HCA bioavailability and their biological effects revealed by epidemiological data, pre-clinical and clinical studies. Moreover, we aim to review the effects of HCAs on gut microbiota diversity and function and its respective influence on host health. © 2019 Society of Chemical Industry.

Antioxidant activity and antibacterial evaluation of new thiazolin-4-one derivatives as potential tryptophanyl-tRNA synthetase inhibitors.

The rapid emergence of bacterial resistance to antibiotics currently available for treating infectious diseases requires effective antimicrobial agents with new structural profiles and mechanisms of action. Twenty-three thiazolin-4-one derivatives were evaluated for their antibacterial activity by determining the growth inhibition zone diameter, the minimum inhibitory concentration (MIC), and the minimum bactericidal concentration (MBC), against gram-positive and gram-negative bacteria. Compounds 3a-c, 3e-h, 6b-c and 9a-c expressed better MIC values than moxifloxacin, against Staphylococcus aureus. Compounds 3h and 9b displayed similar effect to indolmycin, a tryptophanyl-tRNA ligase inhibitor. Due to their structural analogy to indolmycin, all compounds were subjected to molecular docking on tryptophanyl-tRNA synthetase. Compounds 3a-e, 6a-e, 8 and 9a-e exhibited better binding affinities towards the target enzymes than indolmycin. The antioxidant potential of the compounds was evaluated by four spectrophotometric methods. Thiazolin-4-ones 3e, 6e and 9e presented better antiradical activity than ascorbic acid, trolox and BHT, used as references.

A Novel Series of Acylhydrazones as Potential Anti-Candida Agents: Design, Synthesis, Biological Evaluation and In Silico Studies.

In the context of an increased incidence of invasive fungal diseases, there is an imperative need of new antifungal drugs with improved activity and safety profiles. A novel series of acylhydrazones bearing a 1,4-phenylene-bisthiazole scaffold was designed based on an analysis of structures known to possess anti-Candida activity obtained from a literature review. Nine final compounds were synthesized and evaluated in vitro for their inhibitory activity against various strains of Candida spp. The anti-Candida activity assay revealed that some of the new compounds are as active as fluconazole against most of the tested strains. A molecular docking study was conducted in order to evaluate the binding poses towards lanosterol 14α-demethylase. An in silico ADMET analysis showed that the compounds possess drug-like properties and represent a biologically active framework that should be further optimized as potential hits.

Design and Synthesis of Novel 1,3-Thiazole and 2-Hydrazinyl-1,3-Thiazole Derivatives as Anti-Candida Agents: In Vitro Antifungal Screening, Molecular Docking Study, and Spectroscopic Investigation of their Binding Interaction with Bovine Serum Albumin.

In the context of there being a limited number of clinically approved drugs for the treatment of Candida sp.-based infections, along with the rapid development of resistance to the existing antifungals, two novel series of 4-phenyl-1,3-thiazole and 2-hydrazinyl-4-phenyl-1,3-thiazole derivatives were synthesized and tested in vitro for their anti-Candida potential. Two compounds (7a and 7e) showed promising inhibitory activity against the pathogenic C. albicans strain, exhibiting substantially lower MIC values (7.81 µg/mL and 3.9 µg/mL, respectively) as compared with the reference drug fluconazole (15.62 µg/mL). Their anti-Candida activity is also supported by molecular docking studies, using the fungal lanosterol C14α-demethylase as the target enzyme. The interaction of the most biologically active synthesized compound 7e with bovine serum albumin was investigated through fluorescence spectroscopy, and the obtained data suggested that this molecule might efficiently bind carrier proteins in vivo in order to reach the target site.

Antibacterial Evaluation and Virtual Screening of New Thiazolyl-Triazole Schiff Bases as Potential DNA-Gyrase Inhibitors.

The global spread of bacterial resistance to drugs used in therapy requires new potent and safe antimicrobial agents. DNA gyrases represent important targets in drug discovery. Schiff bases, thiazole, and triazole derivatives are considered key scaffolds in medicinal chemistry. Fifteen thiazolyl-triazole Schiff bases were evaluated for their antibacterial activity, measuring the growth inhibition zone diameter, the minimum inhibitory concentration (MIC), and the minimum bactericidal concentration (MBC), against Gram-positive (Staphylococcus aureus, Listeria monocytogenes) and Gram-negative (Escherichia coli, Salmonella typhimurium, Pseudomonas aeruginosa) bacteria. The inhibition of S. aureus and S. typhimurium was modest. Compounds B1, B2, and B9 showed a similar effect as ciprofloxacin, the antimicrobial reference, against L. monocytogenes. B10 displayed a better effect. Derivatives B1, B5-7, B9, and B11-15 expressed MIC values lower than the reference, against L. monocytogenes. B5, B6, and B11-15 strongly inhibited the growth of P. aeruginosa. All compounds were subjected to an in silico screening of the ADMET (absorption, distribution, metabolism, elimination, toxicity) properties. Molecular docking was performed on the gyrA and gyrB from L. monocytogenes. The virtual screening concluded that thiazolyl-triazole Schiff base B8 is the best drug-like candidate, satisfying requirements for both safety and efficacy, being more potent against the bacterial gyrA than ciprofloxacin.

Synthesis of novel thiazolyl-phenyl-thiazole derivatives as promising anti-Candida agents.

New imine derivatives, that contain the thiazolyl-phenyl-thiazole scaffold, were synthesized and evaluated as anti-Candida agents. Elemental analysis and FT-IR, MS, 1H-NMR and 13C-NMR spectroscopic methods confirmed the structure of the newly synthesized compounds. The in vitro antifungal activity was investigated using the broth microdilution method against different Candida spp, including C. albicans, C. krusei and C. parapsilosis. All synthesized compounds exhibited good antifungal activity. Compound 4f showed the highest inhibitory effect against all tested Candida strains, being more potent than fluconazole. The results revealed that the new compounds have promising antifungal activity, with MIC values, ranging from 3.9 to 31.25µg/mL and MFC values between 7.81 and 62.5 µg/mL and could be considered for further development as anti-Candida agents.

Functional constituents of wild and cultivated Goji (L. barbarum L.) leaves: phytochemical characterization, biological profile, and computational studies.

Goji (Lycium barbarum L.) leaves are emphasized as a functional tea or as dietary supplements. The phenolic compound profile, antioxidant, enzyme inhibitory, antimicrobial, and antimutagenic activities of leaf extracts from two selected cultivars in comparison with wild-growing plants have been evaluated. HPLC-DAD/ESI-ToF-MS analysis revealed the presence of phenolic acids and flavonoids with chlorogenic acid and rutin being the dominant compounds in the cultivated plants, whereas rutin and kaempeferol-3-O-rutinoside for wild growing ones. In particular, cv. Erma contained the highest amount of chlorogenic acid and showed a strong tyrosinase-inhibitory effect. Staphylococcus aureus, Listeria monocytogenes, and Penicillium funiculosum were the most sensitive strains when exposed to extracts from cultivated plants. Antimutagenic activity was evaluated by Ames' test. The tested extracts provided high protection against mutagenicity induced by 2-anthramine (2-AA) to Salmonella typhimurium strains TA 98 and TA 100 (max. inhibition (%) 88% and 74.2%, respectively). Overall, Goji leaves are a rich source of bioactive compounds with functional properties that need further risk/benefit evaluation when used in foods or health-promoting formulations.

Design, Synthesis and Antifungal Activity Evaluation of New Thiazolin-4-ones as Potential Lanosterol 14α-Demethylase Inhibitors.

Twenty-three thiazolin-4-ones were synthesized starting from phenylthioamide or thiourea derivatives by condensation with α-monochloroacetic acid or ethyl α-bromoacetate, followed by substitution in position 5 with various arylidene moieties. All the synthesized compounds were physico-chemically characterized and the IR (infrared spectra), ¹H NMR (proton nuclear magnetic resonance), 13C NMR (carbon nuclear magnetic resonance) and MS (mass spectrometry) data were consistent with the assigned structures. The synthesized thiazolin-4-one derivatives were tested for antifungal properties against several strains of Candida and all compounds exhibited efficient anti-Candida activity, two of them (9b and 10) being over 500-fold more active than fluconazole. Furthermore, the compounds' lipophilicity was assessed and the compounds were subjected to in silico screening for prediction of their ADME-Tox properties (absorbtion, distribution, metabolism, excretion and toxicity). Molecular docking studies were performed to investigate the mode of action towards the fungal lanosterol 14α-demethylase, a cytochrome P450-dependent enzyme. The results of the in vitro antifungal activity screening, docking study and ADME-Tox prediction revealed that the synthesized compounds are potential anti-Candida agents that might act by inhibiting the fungal lanosterol 14α-demethylase and can be further optimized and developed as lead compounds.

L (+)-lactic acid production by pellet-form Rhizopus oryzae NRRL 395 on biodiesel crude glycerol.

BACKGROUND: Given its availability and low price, glycerol derived from biodiesel industry has become an ideal feedstock for the production of fuels and chemicals. A solution to reduce the negative environmental problems and the cost of biodiesel is to use crude glycerol as carbon source for microbial growth media in order to produce valuable organic chemicals. In the present paper, crude glycerol was used as carbon substrate for production of L (+)-lactic acid using pelletized fungus R. oryzae NRRL 395 on batch fermentation. More, the experiments were conducted on media supplemented with inorganic nutrients and lucerne green juice. RESULTS: Crude and pure glycerols were first used to produce the highest biomass yield of R. oryzae NRRL 395. An enhanced lactic acid production then followed up using fed-batch fermentation with crude glycerol, inorganic nutrients and lucerne green juice. The optimal crude glycerol concentration for cultivating R. oryzae NRRL 395 was 75 g l(-1), which resulted in a fungal biomass yield of 0.72 g g(-1) in trial without lucerne green juice addition and 0.83 g g(-1) in trial with lucerne green juice. The glycerol consumption rate was 1.04 g l(-1) h(-1) after 48 h in trial with crude glycerol 75 g l(-1) while in trial with crude glycerol 10 g l(-1) the lowest rate of 0.12 g l(-1) h(-1) was registered. The highest L (+)-lactic acid yield (3.72 g g(-1)) was obtained at the crude glycerol concentration of 75 g l(-1) and LGJ 25 g l(-1), and the concentration of lactic acid was approximately 48 g l(-1). CONCLUSIONS: This work introduced sustainable opportunities for L (+)-lactic acid production via R. oryzae NRRL 395 fermentation on biodiesel crude glycerol media. The results showed good fungal growth on crude glycerol at 75 g l(-1) concentration with lucerne green juice supplementation of 25 g l(-1). Lucerne green juice provided a good source of nutrients for crude glycerol fermentation, without needs for supplementation with inorganic nutrients. Crude glycerol and lucerne green juice ratio influence the L (+)-lactic acid production, increasing the lactate productivity with the concentration of crude glycerol.

Optimized Ultrasound-Assisted Enzymatic Extraction of Phenolic Compounds from Rosa canina L. Pseudo-Fruits (Rosehip) and Their Biological Activity.

Two techniques, namely, optimized ultrasound-assisted extraction (UAE) and enzyme-assisted extraction (EAE), were used to promote the extraction of phenolic compounds from the pseudo-fruits of Rosa canina L. (RC). For UAE, an optimization process based on the design of experiment (DoE) principles was used for determining the dependence between three variables (i.e., time of extraction, ultrasound amplitude, and the material-to-water ratio) and the total phenolic content of the samples. For EAE, a 2:1:1 pectinase, cellulase, and hemicellulase enzymatic blend was used as pre-treatment for optimized UAE, inducing a higher total phenolic content. The untargeted phenolic profiling approach revealed a great abundance of lower molecular weight phenolics (1.64 mg Eq./g) in UAE-RC extracts, whilst gallic acid (belonging to hydroxybenzoic acid derivatives) was the most abundant individual compound of both extracts. The unsupervised multivariate statistics clearly discriminated the impact of enzymatic pre-treatment on the phenolic profile of RC pseudo-fruits. Finally, Pearson's correlation coefficients showed that anthocyanins, phenolic acids, and tyrosol derivatives were those compounds mostly correlated to the in vitro antioxidant potential of the extracts, whilst negative and significant (p < 0.05) correlation coefficients were recorded when considering the enzymatic inhibition activities. The highest enzyme-inhibitory activity has been identified against α-glucosidase, which indicates an antidiabetic effect.

Mathematical Modeling and Optimization of Lactobacillus Species Single and Co-Culture Fermentation Processes in Wheat and Soy Dough Mixtures.

To improve food production via fermentation with co-cultures of microorganisms (e.g., multiple lactic acid bacteria-LAB strains), one must fully understand their metabolism and interaction patterns in various conditions. For example, LAB can bring added quality to bread by releasing several bioactive compounds when adding soy flour to wheat flour, thus revealing the great potential for functional food development. In the present work, the fermentation of three soy and wheat flour mixtures is studied using single cultures and co-cultures of Lactobacillus plantarum and Lactobacillus casei. Bio-chemical processes often require a significant amount of time to obtain the optimal amount of final product; creating a mathematical model can gain important information and aids in the optimization of the process. Consequently, mathematical modeling is used to optimize the fermentation process by following these LAB's growth kinetics and viability. The present work uses both multiple regression and artificial neural networks (ANN) to obtain the necessary mathematical model, useful in both prediction and process optimization. The main objective is to find a model with optimal performances, evaluated using an ANOVA test. To validate each obtained model, the simulation results are compared with the experimental data.

Postharvest dormancy-related changes of endogenous hormones in relation to different dormancy-breaking methods of potato (Solanum tuberosum L.) tubers.

Development of an efficient and eco-friendly technique to break tuber dormancy in potato (Solanum tuberosum L.) is highly demanded due to the production of two or more crops annually. Several physiological and hormonal changes have been found to be related to the breaking of tuber dormancy; however, their consistency with genotypes and different protocols have not been well clarified. This study aims to evaluate the effectiveness of four dormancy-breaking methods, that is, plant growth regulator (PGR) dipping in 30, 60, or 90 mgL-1 benzyl amino purine (BAP) and 10, 20, or 30 mgL-1 gibberellic acids (GA3) alone and in the combination of optimized concentrations; electric current application at 20, 40, 60, or 80 Vs; cold pre-treatment at 2, 4, or 6 °C; irradiation at 1, 1.5, 2, 2.5, 3, or 3.5 kGy. In addition, changes in endogenous levels of abscisic acid (ABA), zeatin (ZT), and gibberellin A1 (GA1) in six potato genotypes after subjecting to these methods were investigated. Overall, the highest effective method for dormancy duration was the PGR application which shortened the duration by 18 days, followed by electric current (13 days), cold pre-treatment (9 days), and then irradiation (7 days). The solution of 60 mgL-1 BAP significantly reduced the dormancy duration in all genotypes but did not have a significant effect on the sprout length. While 20 mgL-1 GA3 produced maximum sprout length with a non-significant effect on dormancy duration. The genotype × PGR interaction for dormancy duration was more pronounced in short- and medium-term dormancy genotypes than in long-term dormancy genotypes. The genotypes displayed a significant positive correlation between dormancy duration and ABA levels but exhibited a negative correlation between dormancy duration and ZT as well as GA1 levels. From the first to the third week of storage, ABA was decreased in tubers while, however, ZT and GA1 were increased. The obtained results could be useful for the postharvest storage of potato tuber and the related field of physiological investigation in future.

Short-term responses of Spinach (Spinacia oleracea L.) to the individual and combinatorial effects of Nitrogen, Phosphorus and Potassium and silicon in the soil contaminated by boron.

While of lesser prevalence than boron (B) deficient soils, B-rich soils are important to study as they can cause B toxicity in the field and subsequently decrease crop yields in different regions of the world. We have conducted the present study to examine the role of the individual or combined application of silicon (Si) and NPK fertilizer in B-stressed spinach plants (Spinacia oleracea L.). S. oleracea seedlings were subjected to different NPK fertilizers, namely, low NPK (30 kg ha-2) and normal NPK (60 kg ha-2)], which were also supplemented by Si (3 mmol L-1), for varying levels of B in the soil i.e., 0, 250, and 500 mg kg-1. Our results illustrated that the increasing levels of B in the soil caused a substantial decrease in the plant height, number of leaves, number of stems, leaf area, plant fresh weight, plant dry weight, chlorophyll a, chlorophyll b, total chlorophyll, carotenoid content, net photosynthesis, stomatal conductance, transpiration rate, magnesium content in the roots, magnesium contents in the shoots, phosphorus content in the roots, phosphorus content in the leaves in the shoots, iron content in the roots, iron content in the shoots, calcium content in the roots, and calcium content in the shoots. However, B toxicity in the soil increased the concentration of malondialdehyde, hydrogen peroxide, and electrolyte leakage which were also manifested by the increasing activities of enzymatic [superoxidase dismutase (SOD), peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX)], and non-enzymatic antioxidants (phenolic, flavonoid, ascorbic acid, and anthocyanin content). B toxicity in the soil further increased the concentration of organic acids in the roots such as oxalic acid, malic acid, formic acid, citric acid, acetic acid, and fumaric acid. The addition of Si and fertilizer levels in the soil significantly alleviated B toxicity effects on S. oleracea by improving photosynthetic capacity and ultimately plant growth. The increased activity of antioxidant enzymes in Si and NPK-treated plants seems to play a role in capturing stress-induced reactive oxygen species, as was evident from the lower levels of oxidative stress indicators, organic acid exudation, and B concentration in the roots and shoots of Si and NPK-treated plants. Research findings, therefore, suggested that the Si and NPK application can ameliorate B toxicity in S. oleracea seedlings and result in improved plant growth and composition under metal stress as depicted by the balanced exudation of organic acids.

Impact of Plantago ovata Forsk leaf extract on morpho-physio-biochemical attributes, ions uptake and drought resistance of wheat (Triticum aestivum L.) seedlings.

The present study was conducted to examine the potential role of Plantago ovata Forsk leaf extract (POLE) which was applied at various concentration levels (control, hydropriming, 10, 20, 30, and 40% POLE) to the wheat (Triticum aestivum L.) seedlings. Drought stressed was applied at 60% osmotic potential (OM) to the T. aestivum seedlings to study various parameters such as growth and biomass, photosynthetic pigments and gas exchange characteristics, oxidative stress and response of various antioxidants and nutritional status of the plants. Various growth parameters such as gaseous exchange attributes, antioxidants and nutritional status of T. aestivum were investigated in this study. It was evident that drought-stressed condition had induced a negative impact on plant growth, photosynthetic pigment, gaseous exchange attributes, stomatal properties, and ion uptake by different organs (roots and shoots) of T. aestivum. The decrease in plant growth resulted from oxidative stress and overcome by the antioxidant (enzymatic and non-enzymatic) compounds, since their concentration increased in response to dehydration. Seed priming with POLE positively increased plant growth and photosynthesis, by decreasing oxidative stress indicators and increasing activities of antioxidant (enzymatic and non-enzymatic) compounds, compared to the plants which were grown without the application of POLE. Our results also depicted that optimum concentration of POLE for T. aestivum seedlings under drought condition was 20%, while further increase in POLE (30 and 40%) induced a non-significant (P < 0.05) effect on growth (shoot and root length) and biomass (fresh and dry weight) of T. aestivum seedling. Here we concluded that the understanding of the role of seed priming with POLE in the increment of growth profile, photosynthetic measurements and nutritional status introduces new possibilities for their effective use in drought-stressed condition and provides a promising strategy for T. aestivum tolerance against drought-stressed condition.

Individual and combinatorial effects of SNP and NaHS on morpho-physio-biochemical attributes and phytoextraction of chromium through Cr-stressed spinach (Spinacia oleracea L.).

Chromium (Cr) is a toxic heavy metal that contaminates soil and water resources after its discharge from different industries. A pot experiment was conducted to determine the effects of single and/or combined application of sodium nitroprusside (SNP) (250 µM) and sodium hydrogen sulfide (NaHS) (1 mM) on growth, photosynthetic pigments, gas exchange characteristics, oxidative stress biomarkers, antioxidant machinery (enzymatic and non-enzymatic antioxidants), ion uptake, organic acid exudation, and Cr uptake of spinach (Spinacia oleracea L.) exposed to severe Cr stress [Cr: 0 (no Cr), 150, and 300 µM]. Our results depicted that Cr addition to the soil significantly (P < 0.05) decreased plant growth and biomass, gas exchange attributes, and mineral uptake by S. oleracea when compared to the plants grown without the addition of Cr. However, Cr toxicity boosted the production of reactive oxygen species (ROS) by increasing the content of malondialdehyde (MDA), which is the indication of oxidative stress in S. oleracea, and was also manifested by hydrogen peroxide (H2O2) content and electrolyte leakage to the membrane-bound organelles. The results showed that the activities of various antioxidative enzymes, such as superoxidase dismutase (SOD), peroxidase (POD), catalase (CAT), and ascorbate peroxidase (APX), and the content of non-enzymatic antioxidants, such as phenolic, flavonoid, ascorbic acid, and anthocyanin, initially increased with an increase in the Cr concentration in the soil. The results also revealed that the levels of soluble sugar, reducing sugar, and non-reducing sugar were decreased in plants grown under elevating Cr levels, but the accumulation of the metal in the roots and shoots of S. oleracea, was found to be increased, and the values of bioaccumulation factor were <1 in all the Cr treatments. The negative impacts of Cr injury were reduced by the application of SNP and NaHS (individually or combined), which increased plant growth and biomass, improved photosynthetic apparatus, antioxidant enzymes, and mineral uptake, as well as diminished the exudation of organic acids and oxidative stress indicators in roots of S. oleracea by decreasing Cr toxicity. Here, we conclude that the application of SNP and NaHS under the exposure to Cr stress significantly improved plant growth and biomass, photosynthetic pigments, and gas exchange characteristics; regulated antioxidant defense system and essential nutrient uptake; and balanced organic acid exudation pattern in S. oleracea.

Bioactive Properties of Composites Based on Silicate Glasses and Different Silver and Gold Structures.

Using an ideal biomaterial to treat injured bones can accelerate the healing process and simultaneously exhibit antibacterial properties; thus protecting the patient from bacterial infections. Therefore, the aim of this work was to synthesize composites containing silicate-based bioactive glasses and different types of noble metal structures (i.e., AgI pyramids, AgIAu composites, Au nanocages, Au nanocages with added AgI). Bioactive glass was used as an osteoconductive bone substitute and Ag was used for its antibacterial character, while Au was included to accelerate the formation of new bone. To investigate the synergistic effects in these composites, two syntheses were carried out in two ways: AgIAu composites were added in either one step or AgI pyramids and Au nanocages were added separately. All composites showed good in vitro bioactivity. Transformation of AgI in bioactive glasses into Ag nanoparticles and other silver species resulted in good antibacterial behavior. It was observed that the Ag nanoparticles remained in the Au nanocages, which was also beneficial in terms of antibacterial properties. The presence of Au nanoparticles contributed to the composites achieving high cell viability. The most outstanding result was obtained by the consecutive addition of noble metals into the bioactive glasses, resulting in both a high antibacterial effect and good cell viability.