Table 5.

Intra and inter-day accuracy percentages for secondary metabolites added at three different concentrations (0.25, 0.5 and 1 µM) to coffee leaf extracts.

		Intra-day assay	Inter-day assay
Metabolite	Concentration (µM)	n = 5	n=15
1,3,7-trimethyluric acid	0.25	11.3	16.0
	0.50	25.2	19.9
	1.00	16.3	15.9
3,4-dimethoxycinnamic acid	0.25	3.0	2.1
	0.50	3.0	2.6
	1.00	1.0	0.6
3-Hydroxystilbene	0.25	27.7	12.2
	0.50	6.1	6.8
	1.00	2.2	2.9
4-Hydroxybenzoic acid	0.25	14.5	17.0
	0.50	15.5	18.5
	1.00	14.0	17.1
5-Hydroxytryptophan	0.25	6.5	4.5
	0.50	46.1	28.7
	1.00	43.6	31.8
Apigeninidin	0.25	7.5	5.4
	0.50	9.5	9.2
	1.00	11.4	11.0
Arctigenin	0.25	7.1	7.7
	0.50	3.4	3.7
	1.00	2.6	3.4
Biochanin A	0.25	6.1	8.5
	0.50	3.6	4.8
	1.00	1.0	1.9
Coniferaldehyde	0.25	7.9	7.0
	0.50	6.4	5.8
	1.00	3.0	3.5
Coniferyl alcohol	0.25	30.8	26.1
	0.50	28.3	23.1
	1.00	18.6	17.1
Cyperone	0.25	7.9	3.2
	0.50	1.8	2.3
	1.00	1.0	1.6
Dihydrokaempferol	0.25	5.9	5.3
	0.50	7.6	7.5
	1.00	6.2	5.7
Epicatechin	0.25	29.3	18.5
	0.50	31.7	23.6
	1.00	4.5	9.2
Ferulic acid	0.25	15.3	11.3
	0.50	17.1	14.6
	1.00	1.6	4.6
Gibberellic acid	0.25	5.5	8.9
	0.50	1.5	7.7
	1.00	4.3	8.2
Genistein-7-O-glucuronide	0.25	3.4	8.2
	0.50	1.8	8.2
	1.00	7.6	7.3
Isorhamnetin-3-O-glucoside	0.25	8.4	5.4
	0.50	4.6	5.3
	1.00	0.5	1.7
Jasmonic acid	0.25	6.5	6.7
	0.50	2.6	4.1
	1.00	2.4	3.0
Luteolin	0.25	1.1	4.9
	0.50	4.0	5.2
	1.00	5.0	3.8
Naringenin	0.25	3.1	3.3
	0.50	0.1	1.6
	1.00	2.5	1.6
Orientin	0.25	8.1	15.1
	0.50	8.5	20.3
	1.00	14.0	17.0
Scopoletin	0.25	4.5	4.9
	0.50	6.7	7.5
	1.00	1.6	3.2
Sinapic acid	0.25	30.1	20.4
	0.50	28.7	24.3
	1.00	4.2	6.5
Swertiajaponin	0.25	0.8	25.7
	0.50	6.0	26.9
	1.00	41.4	40.1
Theobromine	0.25	35.4	17.9
	0.50	16.7	12.5
	1.00	5.2	9.1

Intra-day and inter-day accuracy percentages were determined by re-injecting the samples on the same day (n = 5) and on three different days (n = 15), respectively.