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1.
Int J Phytoremediation ; 26(5): 626-638, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37735932

RESUMO

Textile industries use large amounts of water as well as dyes. These dyes containing water are then discharged into the water bodies causing a significant role in water pollution. Brilliant Green dye contributes to many harmful diseases related to the respiratory and gastrointestinal tract. In this study, Symplocos racemosa (SR) agro-waste was chemically treated with acid (SR-HCl) and base (SR-NaOH) and then used for removing Brilliant Green Dye (BGD) on the batch scale. They were characterized by SEM, EDX, FTIR, XRD, TGA and DSC. Optimized conditions were 30 °C temperature, pH 6, adsorbent dose of 0.10 g/25 ml dye solution, shaking speed of 100 revolutions per minute, initial dye concentration of 50 ppm and 35 min time for shaking adsorbent and dye solution. Adsorption data obtained were analyzed using isotherms. The experimental data was found to fit well with the Langmuir model and the maximum adsorption capacity (qmax) of BGD on the SR, SR-HCl, and SR-NaOH was revealed to be 62.90, 65.40, and 71 mg/g respectively. Kinetic data (pseudo-first-order and pseudo-second-order) were evaluated and adsorption tends to follow the pseudo-2nd-order, which indicated the chemisorption mechanism. The results revealed that Symplocos racemosa agro-waste can be considered as the potential biosorbent.


Assuntos
Corantes , Compostos de Amônio Quaternário , Poluentes Químicos da Água , Corantes/química , Biodegradação Ambiental , Mutagênicos , Adsorção , Hidróxido de Sódio , Água , Cinética , Poluentes Químicos da Água/química , Concentração de Íons de Hidrogênio , Termodinâmica
2.
Int J Biol Macromol ; 256(Pt 1): 128285, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38007018

RESUMO

The peels of Trapa natans (TRA) and Citrullus lanatus (CIT), were modified with a variety of chemicals to boost their surface for the optimization of adsorption performance by providing a greater number of additional active binding sites. Citric acid-processed peels (TRAC and CITC) had shown more favorable adsorption performance to eradicate acid violet 7 dye (AVS). Extra and additional active sites generated after chemical processing, including hydroxyl (OH), carboxyl (COOH), amines NH2, carbonyl, and ester (-O-CO-) groups, as evidenced from FTIR and SEM characterizations, may boost the potential of physicochemical integration of adsorbent surface activity in order to promote and encourage the retention of hazardous and risky AVS molecules from the water. The Langmuir isotherm assessed the qmax for the adsorption of AVS on TRAC, CITC, TRA, and CIT to be 212.8, 294, 24.3, and 60.6 mg/g, respectively, whereas the correlation coefficients assessed for both TRAC and CITC were 0.98 and for TRA and CIT were 0.97, closer to unity reflecting monolayer physio-sorption. According to Temkin, the adsorption of AVS on TRAC, TRA, CITC, and CIT gives "BT" values of 1.275, 0.947, 1.085, and 1.211 mg/g, also suggesting physio-sorption. Therefore, chemically modified peels can be employed for detoxification of AVS.


Assuntos
Compostos Azo , Citrullus , Lythraceae , Naftalenossulfonatos , Poluentes Químicos da Água , Adsorção , Ácido Cítrico , Poluentes Químicos da Água/química , Cinética , Concentração de Íons de Hidrogênio
3.
RSC Adv ; 13(38): 26455-26474, 2023 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-37674490

RESUMO

Persistent organic pollutants and dyes cause major problems during ecofriendly wastewater treatment. To overcome this huge problem, several techniques have been considered and in practice for the safe disposal of organic pollutants in recent years; some of them are discussed and compared herein. This review focuses on new trends for wastewater treatment and compares them with certain other techniques alongside their pros and cons; adsorption is considered the safest among them. Adsorbents derived from agri-wastes have good capacity for the removal of these contaminants owing to their great sorption capacity, high reusability, easy operation, etc. Sometimes they need some modifications for the removal of dyes, which are also discussed in this review. This capacity of adsorbents to chelate dye molecules can be affected by factors, such as pH, the concentration of dyes and adsorbents, and temperature of the system. pH has direct influence on the ionization potential and charge on the outer surface of adsorbents. The findings on isotherms, kinetics, and desorption of plant waste-based biomaterials that are safe for the ecosystem and user friendly and are used for hazardous contaminant removal from water are summarized in this review. Finally, conclusions and future perspectives are presented, and some other materials, such as CNTs and MOFs, are also discussed as efficient adsorbents for eliminating dyes from wastewater. Finally, it is predicted that the adsorption of dyes is a more feasible solution for this dye pollution problem.

4.
Int J Anal Chem ; 2023: 9914633, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37090056

RESUMO

A novel pressurized flow system for circular thin-layer chromatography (PC-TLC) has been successfully established and employed for the separation of amino acids, dyes, and pigments for safe medical imaging applications. In this system, the mobile phase is applied to a regular TLC plate through the tube and needle of an intravenous infusion set. The needle was fused in a hole underneath the center of the plate, while the second side end of the tube was connected to a microburette containing the solvent. This new assembly proved itself better in terms of separation time (within 5 minutes) and controlled flow of the solvent and horizontal movement of analyte components over chromatograms with better separation and R f values (glutamine: 0.26, valine: 0.44, phenylalanine: 0.60, chlorophyll a: 0.52, chlorophyll b: 0.43, xanthophyll: 0.18, carotenoid: 0.97, and pheophytin: 0.60) when a number of samples of amino acids, dyes, and pigments were separated by the developed apparatus and the conventional TLC procedure. The developed method was found distinctly rapid, precise, and eco-friendly (less solvent consuming) as compared to traditional ascending TLC.

5.
Dose Response ; 20(4): 15593258221132080, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36262717

RESUMO

Disruption of quorum sensing pathway of pathogenic microbes is considered as novel approach to fight against infectious diseases. The current study was planned to evaluate the antibiofilm and quorum sensing inhibitory potential of Lagerstroemia speciosa. Antibacterial and antibiofilm potential of L. speciosa extracts was determined through agar well diffusion and crystal violet assay against sinusitis isolates, that is, Staphylococcus aureus, Enterococcus faecalis, Proteus mirabilis, and Klebsiella pneumoniae, while quorum sensing inhibition efficacy of L. speciosa extracts was determined through violacein inhibition assay using Chromobacterium pseudoviolaceum as bacterial model. The methanolic extract of L. speciosa presented the highest antimicrobial activity against E. faecalis and antibiofilm activity against K. pneumoniae (77.42 ± 1.51%), while n-hexane extract was found to be least active against all tested bacterial strains. Quorum sensing inhibition activity of L. speciosa extracts against C. pseudoviolaceum showed significant dose-dependent inhibition in violacein production by different concentrations of methanolic extract. Furthermore, none of the extracts of L. speciosa showed any hemolytic activity against human RBCs and hold considerable thrombolytic potential in comparison to streptokinase (75.9 ± .46%). In conclusion, findings suggest that L. speciosa leaves are excellent source of phytochemicals with potent antibiofilm and quorum sensing inhibition potential.

6.
Planta ; 246(5): 803-816, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28803364

RESUMO

MAIN CONCLUSION: Terpenoids play several physiological and ecological functions in plant life through direct and indirect plant defenses and also in human society because of their enormous applications in the pharmaceutical, food and cosmetics industries. Through the aid of genetic engineering its role can by magnified to broad spectrum by improving genetic ability of crop plants, enhancing the aroma quality of fruits and flowers and the production of pharmaceutical terpenoids contents in medicinal plants. Terpenoids are structurally diverse and the most abundant plant secondary metabolites, playing an important role in plant life through direct and indirect plant defenses, by attracting pollinators and through different interactions between the plants and their environment. Terpenoids are also significant because of their enormous applications in the pharmaceutical, food and cosmetics industries. Due to their broad distribution and functional versatility, efforts are being made to decode the biosynthetic pathways and comprehend the regulatory mechanisms of terpenoids. This review summarizes the recent advances in biosynthetic pathways, including the spatiotemporal, transcriptional and post-transcriptional regulatory mechanisms. Moreover, we discuss the multiple functions of the terpene synthase genes (TPS), their interaction with the surrounding environment and the use of genetic engineering for terpenoid production in model plants. Here, we also provide an overview of the significance of terpenoid metabolic engineering in crop protection, plant reproduction and plant metabolic engineering approaches for pharmaceutical terpenoids production and future scenarios in agriculture, which call for sustainable production platforms by improving different plant traits.


Assuntos
Alquil e Aril Transferases/metabolismo , Engenharia Genética , Plantas/química , Terpenos/metabolismo , Alquil e Aril Transferases/genética , Vias Biossintéticas , Engenharia Metabólica , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas/genética , Plantas/metabolismo , Compostos Orgânicos Voláteis/metabolismo
7.
J Sci Food Agric ; 92(15): 3016-22, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22549412

RESUMO

BACKGROUND: Tomato fruit is usually stored at low temperatures for delayed ripening and extended shelf life. However, tomato fruit is susceptible to chilling injury when exposed to low temperatures. In this study, the potential effects of preconditioning with UV-C or UV-B irradiation on chilling injury of postharvest tomato fruit were investigated. RESULTS: Mature-green tomato fruit were exposed to 4 kJ m(-2) UV-C or 20 kJ m(-2) UV-B irradiation and stored for 20 days at 2 °C and subsequently 10 days at 20 °C. UV irradiation was effective in reducing chilling injury index and delaying ethylene peak. Furthermore, UV irradiation preserved storage quality as manifested by reduced weight loss, better retention of firmness, and higher contents of total soluble solids, soluble protein and soluble sugar during subsequent storage at 20 °C. UV-C irradiation significantly delayed the development of the red colour after 10 days of storage at 20 °C. On the other hand, UV irradiation decreased total phenolics content and antioxidant capacity, suggesting possibly reduced stress response to low temperature resulted from enhanced physiological adaptation by UV preconditioning. CONCLUSION: Our results suggest that preconditioning with UV-C or UV-B irradiation in appropriate doses had a positive effect on alleviating chilling injury in postharvest tomato fruit.


Assuntos
Temperatura Baixa/efeitos adversos , Irradiação de Alimentos , Conservação de Alimentos/métodos , Frutas , Solanum lycopersicum , Antioxidantes/análise , Carotenoides/análise , Etilenos/metabolismo , Armazenamento de Alimentos/métodos , Frutas/química , Frutas/metabolismo , Licopeno , Raios Ultravioleta
8.
J Hazard Mater ; 209-210: 121-8, 2012 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-22281027

RESUMO

Greenhouse hydroponic experiments were performed to evaluate potential role of H(2)S on Al toxicity in barley seedlings. Seedlings pretreated with 200 µM NaHS as a donor of H(2)S for 24h and subsequently exposed to 100 µM AlCl(3) for 24h had significantly longer roots than those without NaHS. The promoted root elongation was correlated with a substantial decrease in Al-induced overproduction of lipid peroxidation, electrolyte leakage and Al accumulation in roots, and a marked increase in Al-induced depress activities of Na(+)K(+)-ATPase and H(+)-ATPase. The alleviating role of H(2)S on Al-induced toxicity was also found in a time- and dose-dependent experiment. Addition of 200 and 400 µM NaHS to 100 µM AlCl(3) effectively alleviated Al-toxicity, markedly diminished Al-induced MDA accumulation, and increased chlorophyll content, net photosynthetic rate (Pn) and maximal photochemical efficiency (Fv/Fm) compared with Al alone. Exogenous H(2)S significantly elevated depressed CAT activities, and further improved root POD activity. Moreover, NaHS decreased Al accumulation, but elevated concentrations of S, P, Ca, Mg and Fe in plants. These data suggest that H(2)S-induced alleviation in Al toxicity is attributed to reduced Al uptake and MDA accumulation, improved uptake of P, Ca, Mg and Fe, and elevated ATPase and photosynthetic performance.


Assuntos
Adenosina Trifosfatases/metabolismo , Alumínio/toxicidade , Hordeum/metabolismo , Sulfeto de Hidrogênio/farmacologia , Estresse Oxidativo , Alumínio/farmacocinética , Biomassa , Clorofila/metabolismo , Relação Dose-Resposta a Droga , Hordeum/enzimologia , Hordeum/fisiologia , Malondialdeído/metabolismo , Fotossíntese
9.
J Sci Food Agric ; 90(5): 742-9, 2010 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-20355107

RESUMO

BACKGROUND: Firmness in shiitake mushroom (Lentinula edodes) is an important textural attribute affecting consumer attitudes toward freshness and quality. In this study, the effects of modified atmosphere packaging (MAP) treatments on structure and composition changes in cell walls in relation to the texture of mushrooms were investigated. RESULTS: Shiitake mushrooms were packaged in low density polyethylene bags with no holes (M(0)), two microholes (M(1)), four macroholes (M(2)), stored at 4 degrees C for 16 days with non-wrapped mushrooms as control. Control mushrooms showed the highest firmness value due to significant increase of cellulose and chitin. All three MAP treatments reduced losses of protein and polysaccharides; the M(2) treatment can best preserve the original texture while mushrooms in M(0) became soft and deteriorated, possibly due to higher CO(2) accumulation, lower cellulose and chitin content. Transmission electron microscopy performed on caps at harvest and after 16 days indicated that disintegration of plasmalemma had been alleviated by M(2) treatment, leading to better preservation of the cell wall. CONCLUSION: Our results suggest that differences in firmness of shiitake mushrooms during storage may be due to differences in cellulose and chitin concentrations. M(2) treatment may be a useful way of maintaining shiitake mushrooms texture during storage at 4 degrees C.


Assuntos
Parede Celular/química , Parede Celular/ultraestrutura , Fenômenos Químicos , Manipulação de Alimentos , Embalagem de Alimentos/instrumentação , Cogumelos Shiitake/química , Cogumelos Shiitake/ultraestrutura , Dióxido de Carbono/análise , Celulose/análise , Quitina/análise , Quitina/química , Proteínas Alimentares/análise , Tecnologia de Alimentos/instrumentação , Proteínas Fúngicas/análise , Microscopia Eletrônica de Transmissão , Oxigênio/análise , Permeabilidade , Polietileno/química , Polissacarídeos/análise , Polissacarídeos/química , Controle de Qualidade , Solubilidade , Fatores de Tempo , Vacúolos/ultraestrutura
10.
Food Sci Technol Int ; 16(3): 217-24, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21339137

RESUMO

Whole fresh button mushrooms (Agaricus bisporus) were stored in unsealed bags in two types of modified atmosphere packaging (MAP), namely, active and passive, at 4 °C. The packaging film was 0.04 mm low-density polyethylene and the gas composition of the active MAP was 12% O(2), 2.5% CO(2) and 85.5% N(2). Firmness of Mushroom showed a positive correlation with the accumulation of lignin in the tissue. On the other hand, changes of malondialdehyde content with storage time were proportional to the evolution of browning. The button mushrooms in control treatment developed severe browning at the end of the 15-day storage, while the mushrooms of both active and passive MAP treatments browned slightly. MAP treatments could not inhibit phenylalanine ammonia lyase activity; however, it can reduce the lignification process by the inhibition of peroxidase (POD) activity and the accumulation of lignin. Correlation between the cinnamyl alcohol dehydrogenase activity and lignin accumulation was not obvious. Our results suggested that an increase in the firmness of mushrooms during senescence may be a consequence of tissue lignification, a process associated with increase in POD activity. Both active and passive MAPs were useful for the conservation of tenderness and whiteness in button mushrooms.


Assuntos
Agaricales/metabolismo , Atmosfera/química , Conservação de Alimentos/métodos , Lignina/metabolismo , Malondialdeído/metabolismo , Agaricales/química , Dióxido de Carbono/química , Flavonoides/química , Análise de Alimentos , Nitrogênio/química , Oxigênio/química , Fenóis/química , Polifenóis , Fatores de Tempo
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