Eco-friendly synthesis of crystalline and amorphous copper-based nanomaterials using Moringa oleifera leaf, seed, and stem bark: a sustainable approach for biological and environmental applications

Introduction Green synthesis of nanomaterials using plant extracts has gained significant interest. This method replaces toxic reducing and capping agents with natural sources such as plant extracts, microorganisms, algae, fungi, or biomolecules. In this study, copper-based nanomaterials were synthesized using aqueous extracts from various parts of Moringa oleifera , including leaves, seeds, and stem bark. Methods The synthesized copper oxide materials were characterized using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The prepared materials were then tested for their antimicrobial, antioxidant, and Eriochrome Black-T (EBT) degradation activities. Results and Discussion Structural characterization via XRD revealed the successful formation of a mixed phase of crystalline cuprous oxide and copper (Cu2O/Cu) along with amorphous copper oxide materials. FT-IR analysis confirms that compounds such as polyphenols, alkaloids, flavonoids, terpenoids, and reducing sugars significantly contribute to the synthesis of these copper oxide nanomaterials, supporting their formation. SEM and TEM analysis confirmed the formation of nanomaterials. Additionally, the study measured the concentrations of total phenols, flavonoids, and tannins in various parts of Moringa oleifera to better understand their influence on copper oxide synthesis. Notably, an amorphous copper oxide material derived from Moringa oleifera leaf extract exhibited higher antimicrobial and antioxidant activities and achieved 40% EBT degradation, while the crystalline material showed lower activity. The study discusses these results in detail, correlating the activity with the characterization studies.