Mesoporous carbon nanospheres derived from agro-waste as novel antimicrobial agents against gram-negative bacteria

Porous carbon nanospheres were synthesized from agro-waste garlic peels by a one-pot facile and easy to scale-up pyrolysis method. Surface morphology and structural features of the nanospheres have been studied by field emission scanning electron microscopy, energy-dispersive spectroscopy, X-ray diffraction, and Raman spectroscopy. Fourier transform infrared spectroscopy (FTIR) and N₂ adsorption desorption experiments were explored to detect surface functionality, surface area, and porosity. Average particle diameter of the synthesized nanospheres was 31 ± 6.3 nm and zeta potential of - 25.2 mV ± 1.75 mV. Nanoscale carbon was mesoporous in nature with type IV isotherms, mean pore diameter of 15.2 nm, and total pore volume of 0.032 cm³/g. Minimum inhibitory concentration and minimum bactericidal concentration values of carbon nanospheres against Escherichia coli are 480 ± 0.5 μg/ml and 495 ± 0.5 μg/ml, respectively. Synthesized nanospheres exhibited gram-selective antimicrobial action against Escherichia coli probably linked to membrane deformity due to interaction of nanocarbon with the bacterial membrane. Carbon nanospheres resulting from waste to wealth transformation emerged as promising candidates for antibacterial application. Graphical abstract.