Quantification of hydrogen sulfide concentration using methylene blue and 5,5'-dithiobis(2-nitrobenzoic acid) methods in plants.

Abstract Hydrogen sulfide (H 2 S) has long been considered as a phytotoxin but, nowadays, as a novel signaling molecule at low concentration in plants, which is involved in plant growth, development, and the acquisition of tolerance to abiotic and biotic stresses. H 2 S is commonly found only in very small amounts in most biological systems. To further understand H 2 S functions, accurate measurement of H 2 S concentration in plants is very important. In this chapter, quantificational methods of H 2 S in plant tissues, namely, methylene blue (MB) and 5,5′-dithiobis(2-nitrobenzoic acid) (DTNB) methods, are introduced; the former has higher sensitivity than that of the latter, and the determination limits of MB and DTNB methods are 1.5 × 10 − 7 M (0.005 μg/ml) and 3.7 × 10 − 6 M (0.13 μg/ml), respectively, hoping to stimulate more research into H 2 S signal molecule in plants.