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1.
Ecotoxicol Environ Saf ; 275: 116224, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38518610

RESUMO

Depletion of fossil fuel and pollution by heavy metals are two major global issues. The cell wall of algae consists of polymers of polysaccharides such as cellulose, hemicellulose, alginate, starch, and many others that are readily hydrolyzed to monosaccharides and hence are amenable to fermentation into bioethanol. Moreover, algae contain lipids that may undergo trans-esterification to biodiesel, and can be absorbed by heavy metals. In this study, extraction of lipids from Turbinaria turbinata (common brown alga) from the beach of Sharma, NEOM, Tabuk, Saudi Arabia by different solvents hexane, methanol, and hexane: methanol (1:1), and trans-esterification was performed to obtain biodiesel and investigated by GC.MS. The alga residue after fats extractions by different solvents was used in bioremediation synthetic wastewater containing 50 ppm of As-3, Co+2, Cu+2, Fe+2, Mn+2, and Zn+2. The residue of defatted alga was hydrolyzed by 2% H2SO4 and then fermented to obtain bioethanol. The combination of hexane: methanol (1:1) gave the greatest amount of petroleum hydrocarbons, which contain Tetradecane, 5-methyl, Octacosane, Pentatriacontane, and a small amount of Cyclotrisiloxane, Hexamethyl. The most effective removal % was obtained with alga residue defatted by hexane: methanol (1:1), and methanol, 100% removal of As-3, 83% Co+2, 95% Cu+2, 97.25% Fe+2, Mn+2 79.69%, Zn+2 90.15% with 2 g alga /L at 3 hours. The lowest value of sugar was obtained with hexane: methanol residue but gave the highest bioethanol efficiency. Thus, it is possible to use Turbinaria turbinata, or brown alga as a feedstock to produce bio-diesel, and bioethanol, and to remove heavy metals from wastewater, which may have a great economic and environmental significance.


Assuntos
Metais Pesados , Phaeophyceae , Biocombustíveis , Hexanos , Metanol , Águas Residuárias , Metais Pesados/análise , Plantas , Biodegradação Ambiental , Lipídeos , Solventes
2.
Molecules ; 28(17)2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37687153

RESUMO

Bacterial pathogens cause pain and death, add significantly to the expense of healthcare globally, and pose a serious concern in many aspects of daily life. Additionally, they raise significant issues in other industries, including pharmaceuticals, clothing, and food packaging. Due to their unique properties, a great deal of attention has been given to biogenic metal nanoparticles, nanocomposites, and their applications against pathogenic bacteria. This study is focused on biogenic silver and copper nanoparticles and their composites (UL/Ag2 O-NPS, Ul/CuO-NPs, and Ul/Ag/Cu-NCMs) produced by the marine green alga Ulva lactuca. The characterization of biogenic nanoparticles UL/Ag2 O-NPS and Ul/CuO-NPs and their composites Ul/Ag/Cu-NCMs has been accomplished by FT-IR, SEM, TEM, EDS, XRD, and the zeta potential. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) experiments were conducted to prove antibacterial activity against both Gram-positive and Gram-negative bacteria and anti-biofilm. The FTIR spectroscopy results indicate the exiting band at 1633 cm-1, which represents N-H stretching in nanocomposites, with a small shift in both copper and silver nanoparticles, which is responsible for the bio-reduction of nanoparticles. The TEM image reveals that the Ul/Ag/Cu-NCMs were hexagonal, and the size distribution ranged from 10 to 35 nm. Meanwhile, Ul/CuO-NPs are rod-shaped, whereas UL/Ag2 O-NPS are spherical. The EDX analysis shows that Cu metal was present in a high weight percentage over Ag in the case of bio-Ag/Cu-NCMs. The X-ray diffraction denotes that Ul/Ag/Cu-NCMs, UL/CuO-NPs, and UL/Ag2 O-NPS were crystalline. The results predicted by the zeta potential demonstrate that Ul/Ag/Cu-NCMs were more stable than Ul/CuO-NPs. The antibacterial activity of UL/Ag2 O-NPS, Ul/Ag/Cu-NCMs, and UL/CuO-NPs was studied against eleven Gram-negative and Gram-positive multidrug-resistant bacterial species. The maximum inhibition zones were obtained with UL/Ag2 O-NPS, followed by Ul/Ag/Cu-NCMs and Ul/CuO-NPs in all the tested bacteria. The maximum anti-biofilm percentage formed by E. coli KY856933 was obtained with UL/Ag2 O-NPS. These findings suggest that the synthesized nanoparticles might be a great alternative for use as an antibacterial agent against different multidrug-resistant bacterial strains.


Assuntos
Produtos Biológicos , Nanopartículas Metálicas , Ulva , Cobre/farmacologia , Prata/farmacologia , Antibacterianos/farmacologia , Escherichia coli , Espectroscopia de Infravermelho com Transformada de Fourier , Bactérias Gram-Negativas , Bactérias Gram-Positivas
3.
Sci Rep ; 13(1): 3678, 2023 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-36872381

RESUMO

In comparison to physicochemical and chemical methods, microbial dye biosorption is regarded as an eco-effective and economically viable alternative and is a widely applied method due to its high efficiency and compatibility with the environment. Therefore, the idea of this study is to clarify to what extent the viable cells and the dry biomass of Pseudomonas alcaliphila NEWG-2 can improve the biosorption of methylene blue (MB) from a synthetic wastewater sample. The array of Taguchi paradigm has been conducted to ascertain five variables affecting the biosorption of MB by broth forms of P. alcaliphila NEWG. The data of MB biosorption were familiar to the predicted ones, indicating the precision of the Taguchi model's prediction. The maximum biosorption of MB (87.14%) was achieved at pH 8, after 60 h, in a medium containing 15 mg/ml MB, 2.5% glucose, and 2% peptone, with sorting the highest signal-to-noise ratio (38.80). FTIR spectra detected various functional groups (primary alcohol, α, ß-unsaturated ester, symmetric NH2 bending, and strong C-O stretching) on the bacterial cell wall that participated in the biosorption of MB. Furthermore, the spectacular MB biosorption ability was validated by equilibrium isotherms and kinetic studies (the dry biomass form), which were derived from the Langmuir model (qmax = 68.827 mg/g). The equilibrium time was achieved in about 60 min, with 70.5% of MB removal. The biosorption kinetic profile might be adequately represented by pseudo-second order and Elovich models. The changes in the bacterial cells before and after the biosorption of MB were characterized using a scanning electron microscope. As realized from the aforementioned data, the bacterium is a talented, effective, eco-friendly, and low-cost bio-sorbent for the decolorization and remedy of an industrial effluent containing MB from an aqueous environment. The current outcomes in the biosorption of MB molecules promote the use of the bacterial strain as viable cells and/or dry biomass in ecosystem restoration, environmental cleanup, and bioremediation studies.


Assuntos
Ecossistema , Azul de Metileno , Cinética , Biomassa
4.
Sci Rep ; 12(1): 18291, 2022 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-36316520

RESUMO

The present investigation has been designed by Taguchi and hybrid artificial neural network (ANN) paradigms to improve and optimize the binary sorption of Cobalt(II) and methylene blue (MB) from an aqueous solution, depending on modifying physicochemical conditions to generate an appropriate constitution for a highly efficient biosorption by the alga; Sargassum latifolium. Concerning Taguchi's design, the predicted values of the two responses were comparable to actual ones. The biosorption of Cobalt(II) ions was more efficient than MB, the supreme biosorption of Cobalt(II) was verified in run L21 (93.28%), with the highest S/N ratio being 39.40. The highest biosorption of MB was reached in run L22 (74.04%), with a S/N ratio of 37.39. The R2 and adjusted R2 were in reasonable values, indicating the validity of the model. The hybrid ANN model has exclusively emerged herein to optimize the biosorption of both Cobalt(II) and MB simultaneously, therefore, the ANN model was better than the Taguchi design. The predicted values of Cobalt(II) and MB biosorption were more obedience to the ANN model. The SEM analysis of the surface of S. latifolium showed mosaic form with massive particles, as crosslinking of biomolecules of the algal surface in the presence of Cobalt(II) and MB. Viewing FTIR analysis showed active groups e.g., hydroxyl, α, ß-unsaturated ester, α, ß-unsaturated ketone, N-O, and aromatic amine. To the best of our knowledge, there are no reports deeming the binary sorption of Cobalt(II) and MB ions by S. latifolium during Taguchi orthogonal arrays and hybrid ANN.


Assuntos
Sargassum , Poluentes Químicos da Água , Azul de Metileno/química , Sargassum/química , Cobalto , Adsorção , Cinética , Poluentes Químicos da Água/química , Redes Neurais de Computação , Íons , Concentração de Íons de Hidrogênio
5.
Molecules ; 27(5)2022 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-35268702

RESUMO

There is a very vital antioxidant extracted from microgreen alga. Chlorella vulgaris has major advantages and requires high yield worldwide. Some microalgae require vitamins for their growth promotion. This study was held to determine the impact of different vitamins including Thiamine (B1), Riboflavin (B2), Pyridoxine (B6), and Ascorbic acid (c) at concentrations of 0.02, 0.04, 0.06, and 0.08 mg/L of each. Each vitamin was added to the BG11 growth medium to determine the effect on growth, total carbohydrate, total protein, pigments content, antioxidant activities of Chlorella vulgaris. Moreover, antitumor effects of methanol extract of C. vulgaris without and with the supplement of thiamine against Human prostate cancer (PC-3), Hepatocellular carcinoma (HEPG-2), Colorectal carcinoma (HCT-116) and Epitheliod Carcinoma (Hela) was estimated in vitro. C. vulgaris supplemented with various vitamins showed a significant increase in biomass, pigment content, total protein, and total carbohydrates in comparison to the control. Thiamine was the best vitamin influencing as an antioxidant. C. vulgaris supplemented with thiamine had high antitumor effects in vitro. So, it's necessary to add vitamins to BG11 media for enhancement of the growth and metabolites.


Assuntos
Chlorella vulgaris , Microalgas , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Biomassa , Chlorella vulgaris/metabolismo , Humanos , Masculino , Tiamina , Vitaminas/metabolismo , Vitaminas/farmacologia
6.
Plants (Basel) ; 11(6)2022 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-35336669

RESUMO

Recently, exogenous α-Lipoic acid (ALA) has been suggested to improve the tolerance of plants to a wide array of abiotic stresses. However, there is currently no definitive data on the role of ALA in wheat plants exposed to sodic alkaline stress. Therefore, this study was designed to evaluate the effects of foliar application by ALA at 0 (distilled water as control) and 20 µM on wheat seedlings grown under sodic alkaline stress (50 mM 1:1 NaHCO3 & Na2CO3; pH 9.7. Under sodic alkaline stress, exogenous ALA significantly (p ≤ 0.05) improved growth (shoot fresh and dry weight), chlorophyll (Chl) a, b and Chl a + b, while Chl a/b ratio was not affected. Moreover, leaf relative water content (RWC), total soluble sugars, carotenoids, total soluble phenols, ascorbic acid, K and Ca were significantly increased in the ALA-treated plants compared to the ALA-untreated plants. This improvement was concomitant with reducing the rate of lipid peroxidation (malondialdehyde, MDA) and H2O2. Superoxide dismutase (SOD) and ascorbate peroxidase (APX) demonstrated greater activity in the ALA-treated plants compared to the non-treated ones. Conversely, proline, catalase (CAT), guaiacol peroxidase (G-POX), Na and Na/K ratio were significantly decreased in the ALA-treated plants. Under sodic alkaline stress, the relative expression of photosystem II (D2 protein; PsbD) was significantly up-regulated in the ALA treatment (67% increase over the ALA-untreated plants); while Δ pyrroline-5-carboxylate synthase (P5CS), plasma membrane Na+/H+ antiporter protein of salt overly sensitive gene (SOS1) and tonoplast-localized Na+/H+ antiporter protein (NHX1) were down-regulated by 21, 37 and 53%, respectively, lower than the ALA-untreated plants. These results reveal that ALA may be involved in several possible mechanisms of alkalinity tolerance in wheat plants.

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