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

Table 4

Serotonin concentrations in tomato seedling leaf and root tissues exposed to different treatments of 5-HTP and PF-5-HTP. Numbers in the table represent the mean values ± standard deviation.

Treatment	Serotonin concentration in leaves		Serotonin concentration in roots
	FSU	𝜇g mL^−1	FSU	𝜇g mL^−1
Pure Media	85.3 ± 9.9a	0.27 ± 0.03a	80.6 ± 21.9a	0.27 ± 0.07a
1 mL PBS	86.8 ± 23.6a	0.28 ± 0.07a	81.4 ± 28.9a	0.26 ± 0.08a
5 mL PBS	63.8 ± 17.4a	0.22 ± 0.05a	67.4 ± 47.3a	0.23 ± 0.18a
1 mL 5-HTP	492.1 ± 100.4b	1.33 ± 0.28b	521.3 ± 106.4b	1.41 ± 0.28b
5 mL 5-HTP	512.8 ± 149.4b	1.38 ± 0.47b	563.6 ± 250.7b	1.52 ± 0.67b
1 mL PF-5-HTP	599.3 ± 174.7b	1.61 ± 0.46b	600.7 ± 132.7b	1.61 ± 0.35b
5 mL PF-5-HTP	603.4 ± 91.4b	1.62 ± 0.24b	611.8 ± 60.7b	1.64 ± 0.27b

FSU:Fluorescence Sensitivity Units; PBS:phosphate-buffer-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.