scholarly journals Green process in benzoic acid derivatives synthesis/ Processo verde em síntese de derivados de ácido benzoico

2021 ◽  
Vol 5 (5) ◽  
pp. 2016-2028
Author(s):  
Jaciel Gonçalves dos Santos ◽  
Adriany da Silva ◽  
Jair Marques Junior ◽  
Claudemir Batalini
Keyword(s):  
Antioxidant Activities ◽  
Low Cost ◽  
Artemia Salina ◽  
Aqueous Environment ◽  
Benzoic Acid Derivatives ◽  
Synthetic Strategy ◽  
Cost Efficient ◽  
Toxic Potential ◽  
Ecologically Sustainable ◽  
Layer Chromatography

Employing a methodology that meets various requirements of "Green Chemistry", the substances quinazolinyl benzoate (P1) and N-4-imidazolphenylbenzamide (P2) were synthesized through benzoylation reactions by the classical Schotten-Baumann method, in an aqueous environment and room temperature. The products were purified by recrystallization and characterized by melting point, thin layer chromatography (TLC) and infrared spectroscopy. Qualitative antioxidant activities with the diphenylpicrylhydrazyl radical (DPPH) and toxic potential against Artemia salina Leach larvae were also investigated. Only P2 indicated significant antioxidant activity. According to the medium lethal concentration values (LC50), used for P1 and P2, the toxic potential revealed, respectively, to be moderate for P1 and weak for P2. Despite the low yield obtained for the synthesis of P1, the characterizations indicate success in the preparations, within a synthetic strategy of low cost, efficient and ecologically sustainable.

scholarly journals Production, Characterization and Commercial Formulation of a Biosurfactant from Candida tropicalis UCP0996 and Its Application in Decontamination of Petroleum Pollutants

Processes ◽  
2021 ◽  
Vol 9 (5) ◽  
pp. 885
Author(s):  
Darne Germano Almeida ◽  
Rita de Cássia Freire Soares da Silva ◽  
Hugo Morais Meira ◽  
Pedro Pinto Ferreira Brasileiro ◽  
Elias José Silva ◽  
...  
Keyword(s):  
Candida Tropicalis ◽  
Oil Spills ◽  
Low Cost ◽  
Corn Steep Liquor ◽  
Chemical Characterization ◽  
Artemia Salina ◽  
Motor Oil ◽  
The Stability ◽  
Steep Liquor ◽  
Layer Chromatography

Contamination by oil and its derivatives causes serious damage to the environment, motivating the development of innovative technologies for the removal of these contaminants, such as the use of biosurfactants. In the present study, the biosurfactant from Candida tropicalis UCP0996 produced in the low cost-medium formulated with molasses, residual frying oil, and corn steep liquor, was characterized and its toxicity, formulation, and application in removal and biodegradation of oil were investigated. The surface tension of the medium was reduced to 30.4 mN/m, yielding 4.11 g/L of isolated biosurfactant after 120 h. Tests under extreme environmental conditions indicated the stability of the biosurfactant. Chemical characterization by thin layer chromatography (TLC), Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (1H NMR), and gas chromatography and mass spectroscopy (CG-MS) revealed the glycolipidic nature of the biosurfactant. The isolated biosurfactant showed no toxicity against the microcrustacean Artemia salina, while the properties of the formulated biosurfactant remained stable during 120 days of storage. The biosurfactant removed 66.18% of motor oil adsorbed in marine stones and dispersed 70.95% of oil in seawater. The biosurfactant was also able to increase by 70% the degradation of motor oil by seawater indigenous microorganisms, showing great potential to be applied as a commercial additive in the bioremediation of oil spills.

Comparison of UV- and Derivative-Spectrophotometric and HPTLC UVDensitometric Methods for the Determination of Amrinone and Milrinone in Bulk Drugs

2020 ◽  
Vol 16 (3) ◽  
pp. 246-253
Author(s):  
Marcin Gackowski ◽  
Marcin Koba ◽  
Stefan Kruszewski
Keyword(s):  
Thin Layer ◽  
Thin Layer Chromatography ◽  
High Performance ◽  
Low Cost ◽  
Uv Spectra ◽  
Derivative Spectrophotometry ◽  
Therapeutic Monitoring ◽  
Bulk Drug ◽  
Layer Chromatography ◽  
Standard Solutions

Background: Spectrophotometry and thin layer chromatography have been commonly applied in pharmaceutical analysis for many years due to low cost, simplicity and short time of execution. Moreover, the latest modifications including automation of those methods have made them very effective and easy to perform, therefore, the new UV- and derivative spectrophotometry as well as high performance thin layer chromatography UV-densitometric (HPTLC) methods for the routine estimation of amrinone and milrinone in pharmaceutical formulation have been developed and compared in this work since European Pharmacopoeia 9.0 has yet incorporated in an analytical monograph a method for quantification of those compounds. Methods: For the first method the best conditions for quantification were achieved by measuring the lengths between two extrema (peak-to-peak amplitudes) 252 and 277 nm in UV spectra of standard solutions of amrinone and a signal at 288 nm of the first derivative spectra of standard solutions of milrinone. The linearity between D252-277 signal and concentration of amironone and 1D288 signal of milrinone in the same range of 5.0-25.0 μg ml/ml in DMSO:methanol (1:3 v/v) solutions presents the square correlation coefficient (r2) of 0,9997 and 0.9991, respectively. The second method was founded on HPTLC on silica plates, 1,4-dioxane:hexane (100:1.5) as a mobile phase and densitometric scanning at 252 nm for amrinone and at 271 nm for milrinone. Results: The assays were linear over the concentration range of 0,25-5.0 μg per spot (r2=0,9959) and 0,25-10.0 μg per spot (r2=0,9970) for amrinone and milrinone, respectively. The mean recoveries percentage were 99.81 and 100,34 for amrinone as well as 99,58 and 99.46 for milrinone, obtained with spectrophotometry and HPTLC, respectively. Conclusion: The comparison between two elaborated methods leads to the conclusion that UV and derivative spectrophotometry is more precise and gives better recovery, and that is why it should be applied for routine estimation of amrinone and milrinone in bulk drug, pharmaceutical forms and for therapeutic monitoring of the drug.

scholarly journals Nickel-cobalt oxalate as efficient non-precious electrocatalyst for improved alkaline oxygen evolution reaction

2021 ◽  
Author(s):  
Venkataramanan Mahalingam ◽  
Sourav Ghosh ◽  
Rajkumar Jana ◽  
Sagar Ganguli ◽  
Harish Reddy Inta ◽  
...  
Keyword(s):  
Aqueous Medium ◽  
Oxygen Evolution ◽  
Oxygen Evolution Reaction ◽  
Low Cost ◽  
Next Generation ◽  
Synthetic Strategy ◽  
Nickel Cobalt ◽  
Cobalt Oxalate

The quest for developing next-generation non-precious electrocatalyst is getting aroused in recent times. Herein, we have designed and developed a low cost electrocatalyst by ligand-assisted synthetic strategy in aqueous medium....

scholarly journals Chitosan-Based Nanocomposite Polymeric Membranes for Water Purification—A Review

Materials ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2091
Author(s):  
Angela Spoială ◽  
Cornelia-Ioana Ilie ◽  
Denisa Ficai ◽  
Anton Ficai ◽  
Ecaterina Andronescu
Keyword(s):  
Water Purification ◽  
Antioxidant Activities ◽  
Low Cost ◽  
Synthetic Polymers ◽  
Water Systems ◽  
Polymeric Membranes ◽  
Wastewater Purification ◽  
Toxic Compounds ◽  
The Past ◽  
Materials Used

During the past few years, researchers have focused their attention on developing innovative nanocomposite polymeric membranes with applications in water purification. Natural and synthetic polymers were considered, and it was proven that chitosan-based materials presented important features. This review presents an overview regarding diverse materials used in developing innovative chitosan-based nanocomposite polymeric membranes for water purification. The first part of the review presents a detailed introduction about chitosan, highlighting the fact that is a biocompatible, biodegradable, low-cost, nontoxic biopolymer, having unique structure and interesting properties, and also antibacterial and antioxidant activities, reasons for using it in water treatment applications. To use chitosan-based materials for developing nanocomposite polymeric membranes for wastewater purification applications must enhance their performance by using different materials. In the second part of the review, the performance’s features will be presented as a consequence of adding different nanoparticles, also showing the effect that those nanoparticles could bring on other polymeric membranes. Among these features, pollutant’s retention and enhancing thermo-mechanical properties will be mentioned. The focus of the third section of the review will illustrate chitosan-based nanocomposite as polymeric membranes for water purification. Over the last few years, researchers have demonstrated that adsorbent nanocomposite polymeric membranes are powerful, important, and potential instruments in separation or removal of pollutants, such as heavy metals, dyes, and other toxic compounds presented in water systems. Lastly, we conclude this review with a summary of the most important applications of chitosan-based nanocomposite polymeric membranes and their perspectives in water purification.

Fast Screening for Antioxidant Properties of Flavonoids from Pterogyne nitens Using Electrochemical Methods

2012 ◽  
Vol 95 (3) ◽  
pp. 773-777 ◽  
Author(s):  
Leonardo Luiz Okumura ◽  
Luis Octávio Regasini Regasini ◽  
Daniara Cristina Fernandes ◽  
Dulce Helena Siqueira da Silva ◽  
Maria Valnice Boldrin Zanoni ◽  
...  
Keyword(s):  
Antioxidant Activities ◽  
Low Cost ◽  
Supporting Electrolyte ◽  
Antioxidant Properties ◽  
Reference Electrode ◽  
Structural Features ◽  
Quantitative Detection ◽  
Nonaqueous Media ◽  
Electrochemical Detector ◽  
Fast Screening

Abstract A fast, low-cost, convenient, and especially sensitive voltammetric screening approach for the study of the antioxidant properties of isoquercitrin and pedalitin from Pterogyne nitens is suggested in this work. These flavonoids were investigated for their redox properties using cyclic voltammetry in nonaqueous media using N,N-dimethylformamide and tetrabutylammonium tetrafluorborate as the supporting electrolyte, a glassy carbon working electrode, Ag|AgCl reference electrode, and Pt bare wire counter electrode. The comparative analysis of the activity of rutin has also been carried out. Moreover, combining HPLC with an electrochemical detector allowed qualitative and quantitative detection of micromolecules (e.g., isoquercitrin and pedalitin) that showed antioxidant activities. These results were then correlated to the inhibition of β-carotene bleaching determined by TLC autographic assay and to structural features of the flavonoids.

scholarly journals Synthesis and antioxidant activities of berberine 9-O-benzoic acid derivatives

RSC Advances ◽  
2021 ◽  
Vol 11 (29) ◽  
pp. 17611-17621
Author(s):  
Yanfei Liu ◽  
Shuo Long ◽  
Shanshan Zhang ◽  
Yifu Tan ◽  
Ting Wang ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Benzoic Acid ◽  
Antioxidant Activities ◽  
Benzoic Acid Derivatives

Although berberine (BBR) shows antioxidant activity, its activity is limited.

Fabrication of hydrophobic NiFe2O4@poly(DVB-LMA) sponge via Pickering emulsion template method for oil/water separation

Soft Matter ◽  
2021 ◽  
Author(s):  
Caimei Zhao ◽  
Lei Chen ◽  
Chuanming Yu ◽  
Binghua Hu ◽  
Haoxuan Huang ◽  
...  
Keyword(s):  
Oil Spills ◽  
Low Cost ◽  
Pickering Emulsion ◽  
Template Method ◽  
Water Separation ◽  
Environment Friendly ◽  
Oil Water Separation ◽  
Oil Water ◽  
Cost Efficient

Super-hydrophobic porous absorbent is a convenient, low-cost, efficient and environment-friendly material in the treatment of oil spills. In this work, a simple Pickering emulsion template method was employed to fabricate...

scholarly journals A Novel Adaptive Pixels Segmentation Algorithm for Pavement Crack Detection

2021 ◽  
Author(s):  
Nima Safaei ◽  
Omar Smadi ◽  
Babak Safaei ◽  
Arezoo Masoud
Keyword(s):  
Crack Detection ◽  
Low Cost ◽  
Local Level ◽  
Cost Effective ◽  
Segmentation Algorithm ◽  
Pavement Maintenance ◽  
Detection Systems ◽  
Wide Range ◽  
Cost Efficient ◽  
Pavement Crack Detection

<p>Cracks considerably reduce the life span of pavement surfaces. Currently, there is a need for the development of robust automated distress evaluation systems that comprise a low-cost crack detection method for performing fast and cost-effective roadway health monitoring practices. Most of the current methods are costly and have labor-intensive learning processes, so they are not suitable for small local-level projects with limited resources or are only usable for specific pavement types.</p> <p>This paper proposes a new method that uses an improved version of the weighted neighborhood pixels segmentation algorithm to detect cracks in 2-D pavement images. This method uses the Gaussian cumulative density function as the adaptive threshold to overcome the drawback of fixed thresholds in noisy environments. The proposed algorithm was tested on 300 images containing a wide range of noise representative of different noise conditions. This method proved to be time and cost-efficient as it took less than 3.15 seconds per 320 × 480 pixels image for a Xeon (R) 3.70 GHz CPU processor to determine the detection results. This makes the model a perfect choice for county-level pavement maintenance projects requiring cost-effective pavement crack detection systems. The validation results were promising for the detection of low to severe-level cracks (Accuracy = 97.3%, Precision = 79.21%, Recall= 89.18% and F<sub>1</sub> score = 83.9%).</p>

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