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1.
Environ Res ; 253: 118947, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38744372

RESUMO

In our era, water pollution not only poses a serious threat to human, animal, and biotic life but also causes serious damage to infrastructure and the ecosystem. A set of physical, chemical, and biological technologies have been exploited to decontaminate and/or disinfect water pollutants, toxins, microbes, and contaminants, but none of these could be ranked as sustainable and scalable wastewater technology. The photocatalytic process can harmonize the sunlight to degrade certain toxins, chemicals, microbes, and antibiotics, present in water. For example, transition metal oxides (ZnO, SnO2, TiO2, etc.), when integrated into an organic framework of graphene or nitrides, can bring about more than 90% removal of dyes, microbial load, pesticides, and antibiotics. Similarly, a modified network of graphitic carbon nitride can completely decontaminate petrochemicals. The present review will primarily highlight the mechanistic aspects for the removal and/or degradation of highly concerned contaminants, factors affecting photocatalysis, engineering designs of photoreactors, and pros and cons of various wastewater treatment technologies already in practice. The photocatalytic reactor can be a more viable and sustainable wastewater treatment opportunity. We hope the researcher will find a handful of information regarding the advanced oxidation process accomplished via photocatalysis and the benefits associated with the photocatalytic-type degradation of water pollutants and contaminants.


Assuntos
Eliminação de Resíduos Líquidos , Águas Residuárias , Águas Residuárias/química , Eliminação de Resíduos Líquidos/métodos , Catálise , Poluentes Químicos da Água/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Fotólise , Processos Fotoquímicos
2.
Front Chem ; 11: 1279729, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38053673

RESUMO

Introduction: The present research aimed to fractionate Xanthium strumarium L. (XSL) foliage phenolics into a set of solvents and evaluate their antioxidant potential and in-vivo anti-diabetic activity against Alloxan monohydrate-induced diabetic mice. Methodology: For this purpose, XSL foliage was fractionated into petroleum ether, ethyl acetate, ethanol, and water via orbital type shaking and tested for the presence of phenolics, and their antioxidant and antidiabetic potential. Results and discussion: The results revealed that the ethyl acetate fraction of XSL foliage contained the highest amount of total phenolics 95.25 mg GAE/g of extract, followed by ethanol (65.14 mg GAE/g), petroleum ether (25.12 mg GAE/g), water (12.20 mg GAE/g), and XSL powder (69.13 mg GAE/g). At the end of treatment time (day 18 of oral administration of 400 mg/kg body weight of mice), the ethyl acetate fraction significantly (p ≤ 0.05) lowered blood glucose level (353 ± 10.6 to 220 ± 25.5 mg/dL) which might due to the elevated level of phenolic compounds in this fraction. Conclusion: Overall, it can be speculated that ethyl acetate and ethanol may work efficiently for the enrichment of XSL phenolic without compromising their antidiabetic potential.

3.
J Chromatogr Sci ; 61(9): 875-884, 2023 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-37528755

RESUMO

The present monograph describes the salting-out assisted liquid-liquid microextraction (SALLME) and reverse-phase high-performance liquid chromatography with diode array detector (RP-HPLC-DAD) based quantification of two frequently applied neonicotinoid insecticides, i.e., acetamiprid (ACE) and imidacloprid (IMD), from selected tropical fruits (citrus and guava) and vegetables (tomato, okra and cauliflower). The SALLME conditions like pH, liquid/solid ratio and salt ratio (NaCl/Na2SO4) were varied over a wide range of conditions for the enhanced recovery of IMD and ACE from spiked quality control (low, high and medium) of fruits and vegetables. Meanwhile, RP-HPLC-DAD quantification of IMD and ACE was found to be linear over 1-100 µg/L with the coefficient of determination (R2) value ≥0.997 and slope of the calibration curve (sensitivity) ≥2.3 × 104 peak area unit (µAu). The analysis of selected fruits and vegetables after 0 (1 h), 1, 3, 7, 10 and 14 days of foliar application revealed the presence of IMD and ACE residues in okra and guava higher than maximum residual limits set by the Codex Alimentarius Commission until the third day of spray. Overall, the SALLME-RP-HPLC-DAD was found to be a rapid, selective and expedient choice for the routine analysis of neonicotinoids in environmental and food commodities.


Assuntos
Inseticidas , Microextração em Fase Líquida , Verduras/química , Cloreto de Sódio , Frutas/química , Microextração em Fase Líquida/métodos , Neonicotinoides/análise , Cromatografia Líquida de Alta Pressão/métodos
4.
Phytochem Anal ; 34(1): 30-39, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36151736

RESUMO

INTRODUCTION: The presence of chlorogenic acid (CGA) not only imparts a characteristic flavour to foods but also makes them useful against chronic diseases and metabolic syndromes, especially diabetes mellitus and asthma. OBJECTIVES: The present study was designed to develop a quick, easy, cheap, effective, rugged, and safe (QuEChERS) and pragmatic method to analyse CGA in plant-based products by applying dispersive liquid-liquid microextraction (DLLME) followed by reverse-phase high-performance liquid chromatography under a diode array detector (RP-HPLC-DAD). METHODOLOGY: The DLLME was carried out using Triton X-100 as a dispersant and ethanol as an extraction solvent, while method development and validation activities were performed on a Shimadzu 10-AT HPLC-DAD system equipped with C-18 columns as stationary phases. RESULTS: The well-resolved peak for the standard CGA was observed at 2.92 min for the mobile phase comprising 0.1% aqueous formic acid-ethanol (22:78 v/v) of pH 3.0 programmed under an isocratic flow rate of 1.0 mL/min. The developed method was found to be linear (R2 = 0.9976) over 1-500 µg/mL of CGA concentration at 328 nm. Moreover, the assay was found to be repeatable with RSD ≤ 5.0, and the limit of detection (LOD) and limit of quantification (LOQ) were 0.0281 and 0.0853 µg/mL of CGA, respectively. The DLLME offered an overall recovery rate between 97.60% and 99.54% at an acceptable level of reproducibility [relative standard deviation (RSD) ≤ 5.0]. CONCLUSION: The developed assay was found to be a QuEChERS and pragmatic choice for the high-throughput analysis of CGA in plant-based products/foods. Finally, the analysis revealed the presence of an ample level of CGA in guava fruit in addition to coffee beans and black tea.


Assuntos
Ácido Clorogênico , Microextração em Fase Líquida , Cromatografia Líquida de Alta Pressão/métodos , Microextração em Fase Líquida/métodos , Reprodutibilidade dos Testes , Limite de Detecção , Etanol
5.
Crit Rev Anal Chem ; : 1-27, 2022 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-36148704

RESUMO

Deep Eutectic Liquids (DELs) fall among the rapidly evolving discoveries of the 21st century, and these liquids are considered as alternative solvents to toxic and volatile organic liquids. Nevertheless, the emerging trend regarding the use of DELs in every field of physical and biological sciences, a lot of ambiguities and misconceptions exist about their formation, mechanism, and efficiencies observed or projected. A review of available technical data makes it obvious that these liquids have the potential to revolutionize the underdeveloped areas of analytical chemistry particularly the extraction/enrichment of analytes. To ensure the green and sustainable use of DELs, the researchers need to have a thorough understanding of DELs, their classification, chemistry, the nature and strength of molecular entanglements, and their tailorable features. Many researchers have declared these liquids recyclable but more attentive trials are needed to develop an authentic and straightforward DELs recycling methodology. The present review covers sound background knowledge and expert opinions about the technical definition of DELs, their classification, formation, recyclability, and tailorable features for their application as extraction solvent/sorbent in analytical chemistry.

6.
J Oleo Sci ; 71(3): 425-434, 2022 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-35153244

RESUMO

This study is first to test Pakistani honey bees, Apis dorsata and A. cerana honey samples as anti biofilm, anti quorum sensing (QS) and biofilm dispersal agents honey against multispecies biofilm of bacteria (obtained from obese patients). Briefly, five previously identified isolates Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus, Morganella morganii and Klebsiella pneumoniae (MT448672-MT448676) were selected. Antibiogram study of all five isolates was tested against three antibiotics viz., erythromycin (20 µg/mL), lincomycin (100 µg/mL) and rifampicin (100 µg/mL). In order to form multispecies biofilm, identified bacteria were grown in batch culture by mixing equal volumes (OD590nm = 0.1) of 2, 3 and 5 bacterial isolates. In total 11 groups (g1-g11) were made. Crystal violet (CV) staining method was used to evaluate the antibiofilm potential and biofilm dispersal potential of both honey samples. QS inhibition in P. aeruginosa was measured following culture supernatant method. Antibiogram study showed significant (p < 0.05) resistance by P. aeruginosa against tested antibiotics. E. coli, M. morganii and K. pneumoniae were significantly susceptible to erythromycin and S. aureus to lincomycin. Both honey samples at 2% and 5% concentrations showed significant (p < 0.05) inhibition potential of multispecies biofilm by all test groups (g1-g11). Though A. dorsata honey significantly inhibited biofilm formation at 2 and 5% against all groups but 2% concentration was highly significant against g2-g4 groups. Regarding A. cerana honey, 2% concentration was significantly effective against g1, g4-g7 and g9-g11 groups. Both honey samples significantly inhibited QS at 2 and 5%. The 5% concentration of A. dorsata honey significantly dispersed biofilm by all groups compared to 2% which showed dispersal potential only by g2 and g3 groups. Accordingly, honey samples showed significant antibiofilm, anti-QS and biofilm dispersal potentials thus can be considered as good alternative to antibiotics.


Assuntos
Escherichia coli , Staphylococcus aureus , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Bactérias , Biofilmes , Humanos , Pseudomonas aeruginosa , Percepção de Quorum
7.
J Chromatogr Sci ; 58(8): 779-787, 2020 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-32705114

RESUMO

This study presents a pragmatic and easily scalable maceration-mediated liquid-liquid extraction (MMLLE) and reverse-phase high-performance liquid chromatography (RP-HPLC)-based determination of Silybins from plant material (Curcuma longa L.). The processing of calibration standards revealed that the RP-HPLC method was linear over a concentration range of 1-100 µg/mL with regression coefficient (R2) > 0.9950, limit of detection 0.02 µg/mL and limit of quantification <0.07 µg/mL. The optimum chromatographic conditions resolved Silybin A, Silybin B, Isosilybin A and Isosilybin B within 5 min of analysis time. The reproducible recovery rates of spiked flavonolignans (96.24-115.40%) from quality controls established the effectiveness of MMLLE procedure prior to HPLC determination. The real-time analysis revealed the presence of silybins in C. longa roots. The results further endorse that MMLLE prior to chromatographic determination may provide a more pragmatic analytical solution for the analysis/isolation of silybins.


Assuntos
Cromatografia de Fase Reversa/métodos , Curcuma/química , Extração Líquido-Líquido/métodos , Silibina/análise , Silibina/isolamento & purificação , Cromatografia Líquida de Alta Pressão/métodos , Limite de Detecção , Modelos Lineares , Extratos Vegetais/química , Reprodutibilidade dos Testes , Silibina/química
8.
Prev Nutr Food Sci ; 22(2): 124-130, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28702429

RESUMO

This paper describes in detail proximate composition, nutritional profile, phytochemical constituents, antioxidant activities, antimicrobial potential, and antihemolytic activity (towards human erythrocytes) of various fractions of wild Ganoderma lucidum. Proximate analysis established that wild G. lucidum comprises about 87.02±5.45% of moisture, and the remaining part is a rich source of proteins (8.59±0.37%), crude fiber (54.21±1.2%), and carbohydrate (35.16%) with smaller fat content (3.33 %). Similarly, phytochemical screening revealed the presence of flavonoids (217.51±0.30 mg/g), ascorbic acid (116±7.32 mg/g), phenolics (360.72±34.07 mg/g), ß-carotenes (0.42±0.04 µg/g), and lycopene (0.05±0.00 µg/g). Extracts of wild G. lucidum in various solvents provided first line protection against Escherichia coli and Pasteurella multocida in the order of ethyl acetate> ethanol> methanol> n-hexane> water. Furthermore, aqueous and methanolic extracts of wild G. lucidum were found to be safe towards human erythrocytes. Overall, wild mushroom (G. lucidum) was found to be a good source of dietary supplements, antimicrobial and antioxidant agents in the pursuance of its commercial utilization in food and pharmaceutical industries.

9.
Anal Bioanal Chem ; 409(14): 3645-3655, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28331956

RESUMO

This contribution proposes an enzyme-assisted eco-friendly process for the extraction of non-extractable polyphenols (NEPPs) from black tea leftover (BTLO), an underutilized tea waste. BTLO hydrolyzed with various enzyme formulations was extracted using supercritical carbon dioxide and ethanol as co-solvent (SC-CO2 + EtOH). A conventional solvent extraction (CSE) was performed using EtOH + H2O (80:20, v/v) for comparison purposes. The results revealed that hydrolysis of BTLO with 2.9% (w/w) kemzyme at 45 °C and pH 5.4 for 98 min improved the liberation of NEPPs offering 5-fold higher extract yield (g/100 g) as compared with non-treated BTLO. In vitro antioxidant evaluation and LC-MS characterization of extracts revealed the presence of phenolic acids (mainly caffeic and para-coumaric acid) of high antioxidant value. Scanning electron micrograph of the hydrolyzed BTLO samples indicated noteworthy changes in the ultrastructure of BTLO. Moreover, polyphenol extracts obtained by SC-CO2 + EtOH extraction were found to be cleaner and richer in polyphenols as compared to CSE. The devised enzyme-assisted SC-CO2 + EtOH extraction process in the present work can be explored as an effective biotechnological mean for the optimal recovery of antioxidant polyphenols. Graphical abstract Enzymatic pretreatment can effectively liberate non-extractable polyphenols (NEPPs) while hydrolyzing the cellulosic and hemicellulosic framework of black tea left overs (BTLO).


Assuntos
Antioxidantes/isolamento & purificação , Camellia sinensis/química , Cromatografia com Fluido Supercrítico/métodos , Química Verde/métodos , Polifenóis/isolamento & purificação , Chá/química , Biocatálise , Ácidos Cafeicos/isolamento & purificação , Dióxido de Carbono/química , Cromatografia com Fluido Supercrítico/instrumentação , Ácidos Cumáricos , Desenho de Equipamento , Etanol/química , Química Verde/instrumentação , Hidrólise , Propionatos/isolamento & purificação , Eliminação de Resíduos , Solventes/química , Espectrometria de Massas por Ionização por Electrospray/métodos
10.
Biomed Chromatogr ; 31(2)2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27503066

RESUMO

The present study was planned to optimize and validate an expedient reverse-phase high chromatography (RP-HPLC) based protocol for the analysis of deferoxamine (DFO) and ferrioxamine (FO) in urinary execration of patients suffering ß-thalassemia major. The optimized RP-HPLC method was found to be linear over the wide range of DFO and FO concentration (1-90 µg/mL) with appreciable recovery rates (79.64-97.30%) of quality controls at improved detection and quantitation limits and acceptable inter and intraday variability. Real-time analysis of DFO and FO in the urine of thalassemic patients (male and female) at different intervals of Desferal®(Novartis Pharmaceuticals Corporation) injection revealed DFO and FO excretion at significantly (p < 0) different rates. The maximum concentrations of DFO (76.7 ± 3.06 µg/mL) and FO (74.2 ± 3.25 µg/mL) were found in urine samples, collected after 6 h of drug infusion while the minimum levels of DFO (1.10 ± 0.12 µg/mL) and FO (2.97 ± 0.13 µg/mL) were excreted by patients after 24 h. The present paper offers balanced conditions for an expedient, reliable and quick determination of DFO and FO in urine samples.


Assuntos
Meios de Contraste/farmacocinética , Desferroxamina/urina , Compostos Férricos/urina , Sideróforos/urina , Talassemia beta/urina , Adolescente , Criança , Pré-Escolar , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia de Fase Reversa/métodos , Feminino , Humanos , Limite de Detecção , Masculino
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