34 research outputs found
Antioxidant properties of cultured mycelia from four pleurotus species produced in submerged medium.
The ethanolic extracts of dried cultured mycelia of Pleurotus ostreatus, Pleurotus eryngii, Pleurotus florida, and Pleurotus sajor-caju were analyzed for antioxidant activity in different systems. Tests used are as follows: reducing power, free radical scavenging, superoxide anion radical scavenging, total antioxidant activity, metal chelating activitiy, etc.; total phenolic content was determined. The percentage inhibition of P. ostreatus, P. eryngii, P. florida, and P. sajor-caju at 20 mg/mL concentration on peroxidation in a β-carotene–linoleic acid system was 57.19, 60.68, 62.12, and 58.81%, respectively. The reducing power of P. eryngii was higher than the other samples, and its value was 0.86 at 10 mg/mL concentration. P. ostreatus and P. sajor-caju proved to be better at scavenging superoxide anion radicals than the P. eryngii and P. florida. In the scavenging effect of DPPH radical test, P. ostreatus showed the highest activity potential and P. sajor-caju showed the strongest metal chelating capacity
Solid phase extraction based on the use of agaricus arvensis as a fungal biomass for the preconcentrations of Pb and Al prior to their determination in vegetables by ICP-OES.
A solid phase extraction (SPE) method based on the use of a fungal biomass as sorbent was developed for the preconcentrations of Pb and Al. Agaricus arvensis was immobilized on Amberlite XAD-4 and loaded onto a column. Important parameters such as pH and flow rate of the solution, amount of biosorbent and resin, volume of sample solution, which affect the efficiency of the preconcentration procedure for Pb and Al, were optimized. The effect of possible interfering ions, i.e., Cd2+, Cu2+, Ni2+, Zn2+, Co2+, Na+, K+, Ca2+, Mg2+, and Fe2+, was investigated. Experiments on the repeatability of the solid phase column showed that the same column could be used at least 30 cycles without loss of the biosorption efficiency for the recovery of Pb and Al. The limit of detection (LOD) of Pb and Al was found to be 0.10 ng mL-1 and 0.03 ng mL-1, respectively. The sensitivity of ICP-OES improved 39.8-fold for Pb and 39.5-fold for Al. Linearity was obtained in the concentration range of 1.25–50.0 ng mL-1 for Pb and 0.5–50.0 ng mL-1 for Al. The relative standard deviation (RSD) of the method under optimum conditions was lower than 8.4% (n=5) for Pb and Al, which was validated through the analysis of certified reference tea and poplar leaves samples. The biosorption capacity of immobilized Agaricus arvensis for Pb and Al was found to be 31.2 mg g-1 and 45.7 mg g-1, respectively. The developed method was applied to determine the concentrations of Pb and Al in various edible vegetable samples (cucumber, okra, tomato, beans, aubergine, watermelon, zucchini, pepper, melon, lettuce, roka, purslane, scallion, cress, parsley, cabbage, sugar cane, and basil) grown along the cultivated banks of the Tigris River in Diyarbakır, Turkey
Preconcentration of metal ions using microbacteria
This review (160 refs). covers the current state of the art of microbacteria-based sorbents for preconcentration of metal ions at trace levels. We highlight advantages and major challenges of the techniques and discuss future perspectives of both batch and column-based methods. Particular attention is paid to the preconcentration of metal ions using resinimmobilized microbacteria for solid phase extractions. We also discuss detection methods including UV–vis spectrophotometry, FAAS, ICP-OES and ICP-MS. Analytical figures of merit are compared, and examples are given for the application to a variety of samples including food, beverages, alloys, water, soil, and geological samples
The use of fungal biomass agaricus bisporus immobilized on amberlite XAD-4 resin for the solid phase preconcentration of thorium
Solid-phase extraction method was developed for the preconcentration of thorium (Th). Fungal biomass Agaricus bisporus was immobilized to Amberlite XAD-4 as solid-phase sorbent. The critical parameters such as pH of the sample solution, flow rate of the sample, volume of the sample, and the effect of major ions that affect the preconcentration of thorium in this system were evaluated. The optimum pH for the sorption of Th is 6.0, and quantitative elution occurs with 1.0 mol L−1 HCl. The loading capacity was determined as 0.079 mmol g−1. The optimized method was validated through analysis of the certified reference material of tea leaves (NCS ZC73014) and successfully applied to the determination of Th in a real ore sample with satisfactory results
Design of novel binuclear phthalocyanines formed by dioxyphenyl bridges: Synthesis and investigation of thermal and antioxidant properties
4,4_-(1,4-Phenylenebis(oxy)diphthalonitrile was synthesized by reaction of hydroquinone with 4-nitrophthalonitrile. Binuclear metallophthalocyanines 2–4 were obtained by the reaction between 4,4_-(1,4-phenylenebis(oxy)diphthalonitrile and 4-(benzo [d] [1,3] dioxol- 5-ylmethoxy)phthalonitrile in the presence of metal salts. These new compounds were characterized by using elemental analysis, FTIR, 1H-NMR and UV/Vis spectroscopic data. Thermal properties of phthalocyanines 2-4 were investigated by TG and DTA. In addition, antioxidant properties of compounds II, 3 and 4 were investigated. Their radical-scavenging capacity and chelating effects was fully studied. The maximum 1,1-diphenyl-2-picrylhydrazyl radicals (DPPH) were obtained from compound 3. Chelating effects on ferrous ions were 91.6 % at concentration of 100 mgL–1 with compound II
Synthesis and Characterization of Bionanomaterials and Evaluation of Their Antioxidant, Antibacterial, and DNA Cleavage Activities
In this study, the hexagonal boron nitride (hBN) (1), poly-levodopa (P-L(DP) (2), P-L(DP) coated hBN (hBN@P(L-DP)) (3), and silver nanoparticles (AgNPs) decorated hBN@P(L-DP) (hBN@P(L-DP)-AgNPs) (4) were synthesized and characterized by multiple spectroscopic techniques. Additionally, their biological properties such as antioxidant, antibacterial, and DNA cleavage activities were determined. It is worth noting that, products 3 and 4 were newly synthesized structures. The antioxidant activities of all the nanomaterials 1, 2, 3, and 4 nanomaterials were investigated using some tests such as DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging and reducing power ability. Among the synthesized nanomaterials, product 2 exhibited the highest radical scavenging (64.8±1.94 %) and reducing power activity (0.61±0.017) at a concentration of 200 mg L−1. Product 4 was determined to have antibacterial activity against all three Gram-positive and three Gram-negative test bacteria. In addition, all the nanomaterials were tested for cleavage activity using pBR 322 plasmid DNA, as a result of which it was determined that only product 4 showed the ability of cleavage from both chains of DNA
Preconcentration of Sn in real water samples by solid phase extraction based on the use of helvella leucopus as a fungal biomass prior to its determination by ICP-OES
Recently, biosorbents of biological origin such as fungus, algae, and bacteria have found special application as packing material in solid phase extraction (SPE). In this study, an alternative SPE method was developed and validated for the preconcentration of Sn prior to its determination by inductively coupled plasma optical emission spectrometry (ICPOES). Helvella leucopus, a fungal biomass, was used as the biosorbent in the column studies. Experimental parameters, such as Ph and flow rate of the solution, amounts of biosorbent and resin, and volume of the sample solution which affects the analytical results, were investigated. Effects of possible interfering ions on the SPE preconcentration of Sn were investigated. The sensitivity of ICP-OES was improved 47.1 times for Sn. The LOD and LOQ values were 0.06 and 0.21 ng mL-1, respectively. Linearity was obtained in the concentration range of 1.0–30 ng mL-1 for Sn. The loading capacity of Helvella leucopus immobilized Amberlite XAD-4 was 10.4 g g-1. The concentrations of Sn in the water samples from the Tigris River were determined using the developed
method and validated by analysis of the certified reference material NWTM-26.3 Fortified Water sample
Biosorption of 2,4-D, 2,4-DP and 2,4-DB from aqueous solution by using thermophilic anoxybacillus flavitermus and analysis by high performance thin layer chromatography: equilibrium and kinetic studies
In this study, the potential biosorption characteristics of the thermophilic Anoxybacillus flavithermus (A. flavithermus) was investigated for the removal of the chlorophenoxy acid derivates, namely, 2,4-dichlorophenoxy acetic acid (2,4-D), 2,4-dichlorophenoxy propanoic acid (2,4-DP or dichlorprop), and 2,4-dichlorophenoxy butyric acid (2,4-DB). The experiments were performed for the simultaneous biosorption of the studied pesticides. Optimum biosorption conditions were determined as a function of contact time, pH of the solution, amount of biomass, and initial pesticides concentrations. The concentrations of the pesticides in the remaining solutions were simultaneously analyzed by high performance thin layer chromatography. The optimum parameters were found as pH: 4.0 for biosorption medium, 60 min of contact time, 50 mg of bacteria, and 50 mg L21 of initial pesticides concentrations. Langmuir and Freundlich models were applied to describe the biosorption isotherm of the pesticides by A. flavithermus as biomass. Biosorption of pesticides on to A. flavithermus showed pseudo first-order rate kinetics at different initial concentration of pesticides and different temperatures. The experimental adsorption data were fitted both the Langmuir and Freundlich adsorption models. Fourier-transform Infrared spectroscopy was used to understand the bonding mechanism of pesticides to biosorbent and surface functionality of the biosorbent The highest pesticide uptake was calculated from Langmuir isotherm and found to be 24.15 mg/g for 2,4-D Among the studied pesticides, 2,4-DP showed difference adsorption behavior. According to in your comments the reason of this that 2,4-DP contain an asymmetric carbon atom, which provide a molecular chirality
Biosorption of chlorophenoxy acid herbicides from aqueous solution by using low-cost agricultural wastes.
The potential biosorption abilities of apple shell (AS), orange peel (OP), banana peel (BP), and millet waste (MW) as a bio-waste material to remove 2,4-dichlorophenoxy acetic acid (2,4-D), 2,4-dichlorophenoxy propanoic acid (2,4-DP), and 2,4-dichlorophenoxy butyric acid (2,4-DB) from aqueous solution were investigated in batch condition. Optimum biosorption conditions were determined as a function of contact time, pH of the solution, amount of biomass, and initial pesticide concentrations. The concentrations of the pesticides in the remaining solutions were simultaneously determined by high performance thin layer chromatography.
Langmuir and Freundlich models were applied to describe the biosorption isotherm of the pesticides by agricultural wastes. The experimental adsorption data were fitted to Langmuir adsorption models (r2 > 0.99). It was found that adsorption of 2,4-DP was higher for all biosorbent. The highest maximum adsorption capacities of 2,4-DP were found as 40.08, 22.71, 33.26, and 45.45 mg/g, respectively, for AS, OP, BP, and MW. Maximum adsorption capacity was obtained for 2,4-D as OP >MW> BP > AS, 2,4-DP as MW> AS > BP > OP, and 2,4-DB as OP > AS > BP > MW. From the results, it can be said that MW was an effective biosorbent for removal of 2,4-DP and OP was an effective biosorbent for removal of 2,4-D and 2,4-DB through the studied pesticides. Optimum biosorption conditions were determined as 60 min of contact time, 100 mg of biomass, AS at pH 6.0, OP at pH 6.0, MW at pH 7.0, and BP at pH 7.0. FT-IR was employed to understand the surface properties of biosorbents. According to the results, agricultural wastes have high adsorption capacity
Novel cobalt (II), zinc (II) phthalocyanines bearing discrete substituents: Synthesis, characterization, aggregation behavior, electrochemical properties and antioxidant activity
A new phthalonitrile derivative bearing 3,4,5-trimethoxybenzyloxy and chloro-substituents at peripheral position was prepared by a nucleophilic displacement reaction. Cyclotetramerization of phthalonitrile derivative in dimethylsulfoxide (DMSO) gave the metallophthalocyanines. Novel Co(II), Zn(II) phthalocyanines (Pcs) were obtained from the reaction 4-[(3,4,5- trimethoxybenzyloxy]-5-chlorophthalonitrile and metal salts. The novel compounds have been characterized by using elemental analysis, UV-Vis, FTIR, 1H-NMR spectral data. The aggregation behaviors of Co(II), Zn(II) Pcs were also investigated. These metallophthalocyanines do not show any aggregation behavior between 1.2 × 10−5 and 4.0 × 10−6Mconcentration range in DMF. The antioxidant activities of Pcs were investigated antioxidant assays such as free radical scavenging ability of 1,1-diphenyl-2-picryl-hydrazyl (DPPH) and ferrous ion chelating ability. Furthermore, the redox properties of the Pcs complexes were investigated by using cyclic voltammetry