Methanol-enhanced removal and metabolic conversion of formaldehyde by a black soybean from formaldehyde solutions

Methanol regulation of some biochemical and physiological characteristics in plants has been documented in several references. This study showed that the pretreatment of methanol with an appropriate concentration could stimulate the HCHO uptake by black soybean (BS) plants. The process of methanol-stimulated HCHO uptake by BS plants was optimized using the Central Composite Design and response surface methodology for the three variables, methanol concentration, HCHO concentration, and treatment time. Under optimized conditions, the best stimulation effect of methanol on HCHO uptake was obtained. ¹³C-NMR analysis indicated that the H¹³CHO metabolism produced H¹³COOH, [2-¹³C]Gly, and [3-¹³C]Ser in BS plant roots. Methanol pretreatment enhanced the metabolic conversion of H¹³CHO in BS plant roots, which consequently increased HCHO uptake by BS plants. Therefore, methanol pretreatment might be used to increase HCHO uptake by plants in the phytoremediation of HCHO-polluted solutions.