Nanoparticle fabrication of calcium oxide (CaO) mediated by the extract of red dragon fruit peels (Hylocereus Polyrhizus) and its application as inorganic-anti-microorganism materials

The objective of this study was to biosynthesize calcium oxide (CaO) with the employment of the extract of red dragon fruit peels (Hylocereus polyrhizus) as the biologically reductive agent and to investigate the catalytic performance of the biosynthesized CaO on Candida albicans in aqueous conditions. In the initial process, the biosynthesis was carried out by conditioning the extract of dragon fruit peels reacting with CaCl2 center dot 2H(2)O as a precursor of calcium metal in the system. Continuing the characterization process of the biosynthesized results using Ultraviolet-visible spectroscopy (UV-Vis), it had maximum absorbance at 450 nm, which was indicated by the presence of Ca-O bond in the biosynthesized sample. Another characterization using Fourier-transform infrared spectroscopy (FTIR) showed the typical wave numbers that were observed at 505.35 and 540.07 cm(-1). This could be noticed on the IR absorption spectra of CaO crystals. The physical analysis using Scanning electron microscope (SEM) proved the morphology of the biosynthesized CaO which was in the rod shape (fibber), in which the Energy Dispersive X-Ray (EDX) confirmed the contents of the biosynthesized sample. The contents were calcium (29.06%) and oxygen (43,94%). Finally, X-ray diffraction (XRD) characterization showed that the average size of the biosynthesized CaO was 18.98 nm, which means that the produced materials can be classified into Nanoscale based on their sizes. The anti-microorganism activity of the biosynthesized CaO was observed using antifungal experiment against Candida albicans at various concentrations of 4500, 5900 and 6600 mu g/mL under turbidimetry method. This indicated its inhibition percentage of 62.2%, 83.5% and 91.8%, respectively. This study revealed that the aqueous extract of the red dragon fruit peels (H. Polyrhizus) was successfully used as biological mediator on the CaO biosynthesis, and the biosynthesized CaO showed inorganic antifungal activity against C. Albicans.