Design and Synthesis of a New Anticancer and Antimicrobial Nanocomposite by Microalgae Based on an Up-down Approach

 Use of natural ingredients is a safe efficient approach to overcome various diseases. Encapsulated ginger extract has shown improved physicochemical characterizations, compared with that, the ginger extract has. In this study, a natural system integrated with ginger bioactive compounds (6-gingerol) and green microalgae of Chlorella vulgaris was reported to increase bioactive compounds medicinal effectiveness and introduce a novel food supplement.

 First, nanoparticles of microalgae were produced using ball-milling technique. Ethanolic ginger extract, loaded on microalga nanoparticles, was investigated at various pH values (2-7.4) to effectively release the active agents. Various analytical techniques (e.g., Fourier transform infrared, thermogravimetric analyses) were used to characterize the nanocomposite and investigate its anticancer and antimicrobial effects.

 Dynamic light scattering showed a medium size of 20.9 nm for the microalga nanoparticles. The release assay of ginger polyphenols showed a releasing process controlled by the pH. Fourier transform infrared, thermogravimetric analysis and differential thermal analysis revealed adsorption of ginger extract on nano Chlorella vulgaris surface. Moreover, 2,2-diphenyl-picrylhydrazyl bioassay results on the nanocomposite (GE@nano C.v) verified its significant antioxidant, antibacterial and anticancer activities. The nanocomposite has the minimum inhibitory effect on human breast adenocarcinoma cells and bacterial growth at 1 and 6.25 mg ml-1 concentrations, respectively. In brief, adsorption of ginger extract on the microalga nanoparticle surfaces enhanced physical and chemical characteristics of the ginger extract, compared to its free form. Bioactive compounds in Chlorella vulgaris and ginger extract strengthen their reported activities. Furthermore, microalgal nanoparticles could act as a safe carrier for the controlled release of 6-gingerol in addition to their nutraceutical characteristics.