Fluorine-Tagged 5-Hydroxytryptophan to Investigate Amino Acid Metabolism In Vivo

Table 3

Growth response of tomato seedlings to different high-dose (5 mL) treatments. High dose of 5-HTP contains ~1.0 𝜇g m𝐿⁻¹ 5-HTP in 5 mL PBS. High dose of PF-5-HTP contains ~1.7 𝜇g m𝐿⁻¹ PF-5-HTP per m𝐿⁻¹ PBS (biologically equivalent to 3.4 𝜇g 5-HTP). Numbers in the table represent the mean values ± standard deviation. Each value is based on 3 replicates with 4 plants each (12 per treatment).

Treatment	Stem length (cm)	Root length (cm)	Leaf biomass (g)	Root biomass (g)
5 mL PBS	5.7 ± 1.9a	5.8 ± 2.3a	1.0 ± 0.5	4.7 ± 2.2a
5 mL 5-HTP	5.4 ± 2.0a	5.3 ± 1.3a	1.1 ± 0.4	7.7 ± 2.2a
5 mL PF-5-HTP	3.8 ± 0.7b	3.6 ± 1.1b	0.6 ± 0.3	4.5 ± 0.8a

PBS:phosphate-buffered saline; 5:HTTP:5-hydroxytryptophan; PF-5-HTTP:5-hydroxytryptophan tagged with multiple-fluorine atoms. Values with the same letters (a, b) were not significantly different at probability level 𝛼< 0.05 as determined by one-way analysis of variance with the Student-Newman-Keuls multiple-comparison test.