Ascorbic Acid Functionalized Anti-Aggregated Au Nanoparticles for Ultrafast MEF and SERS Detection of Tartrazine: An Ultra-Wide Piecewise Linear Range Study

Tartrazine, as a synthetic food colorant, is harmful to health upon excessive intake. In this work, we developed a simple, sensitive and ultrafast method to detect tartrazine effectively. Specifically, we...

Treatment of the Allura red food colorant contaminated water by a novel cyanobacteria Desertifilum tharense

The biosorption properties of a newly isolated and identified cyanobacterium called Desertifilum tharense were investigated in the current study. Following morphological and molecular identification (16S rRNA sequencing analysis), the food colorant removal potential of this new isolate was determined. Moreover, the isotherm, kinetic, and thermodynamic studies were performed, and also the biosorbent characterization was studied after and before colorant biosorption with FTIR and SEM analysis. Additionally, the changes in chlorophyll content of the biosorbent were examined after and before colorant treatment. The newly isolated cyanobacterial biosorbent removed 97% of Allura red food colorant/dye at 1,500 mg L−1 initial dye concentration successfully at optimal conditions. Langmuir isotherm and pseudo-second-order kinetic models were fitted with the biosorption of the dye. The D-R model showed that the biosorption process physically occurred. The chlorophyll-a content of the biosorbent was negatively affected by the biosorption. The newly isolated and identified cyanobacterium seems to be a successful candidate for the use to treat highly dye concentrated wastewaters.

The Chemical and Cytotoxic Properties of Sambucus nigra Extracts—A Natural Food Colorant

Elderberry fruits contain valuable components that are beneficial to human health. Owing to the high content of anthocyanins, elderberry extracts can be used as natural food colorants with health-promoting properties. Moreover, the development of new natural food dyes enables the reduction in the use of synthetic ones. Anthocyanins-rich elderberry dry extracts (EDE) were prepared from the same batch of frozen fruits applying water extraction, followed by membrane separation (batch B1) or purification by column chromatography (batch B2) and then spray-dried. Subsequently, the content of anthocyanins, flavonols, and polyphenols was determined. The extract obtained with the application of column chromatography (B2) contained 33% anthocyanins, which is more than typical market standards, whereas the extract B1 contained 14% anthocyanins. The color properties of both extracts were also determined. Since water was used as an extractant, the extracts are well soluble in water and can therefore be used as a natural food colorant. The cytotoxic activity of both extracts was additionally determined using the MTT test and the tumor cells of the A-549, A-2780, MCF-7, Caco-2 line, and Peripheral blood mononuclear cells. It was revealed that both EDEs inhibit the proliferation of cancer cells, except those of the lung cancers. Extract B2 showed a much stronger cytotoxic effect. Additionally, both extracts stimulate the proliferation of peripheral blood mononuclear cells since they may have immunostimulatory properties.