Potential role of multiwalled carbon nanotube priming in boosting nitrogen metabolism and nutritional value during the sprouting process

Sprouts are well known for having a remarkable nutritional profile. Enhancing plant chemical composition and quality of sprouts is essential since these metabolites offer numerous health advantages. To this end, this study aimed to investigate the effects of priming with multiwalled carbon nanotubes (MWCNTs) on the growth and nitrogen (N) metabolism of four horticultural plants, namely, Trigonella foenum-graecum, Linium grandiflorum, Lepidium sativum, and Anethum gravelones. The properties of our synthesized MWCNTs included three characteristic peaks 3434, 1539, and 1068 cm⁻¹ attributable to the stretching vibration of O–H, bending vibration, and C − O, respectively. MWCNT priming increased the sprouting process by inducing biomass and protein accumulation. MWCNT priming improved N metabolism, including amino acid and polyamine metabolism. At the amino acid level, there was an increase in amino acid levels (e.g., glycine, lysine, asparagine, and glutamic acid) as well as their metabolic enzyme activities, including glutamine synthetase (GS), threonine synthetase (TS), and glutamate synthetase (GOGAT). Increased polyamine levels like spermine, putrescine, and spermidine were also associated with boosting their related biosynthetic enzyme activities, i.e., arginine decarboxylase (ADC), ornithine decarboxylase (ODC), spermidine synthase, and spermine synthase (SpmS). This improvement of nitrogen metabolic pathways highlights the potential of MWCNT to boost the chemical composition of horticultural plants.