. 2015 Sep 25;6:760. doi: 10.3389/fpls.2015.00760

Table 5.

Relative changes of phenolic compounds under drought or active photorespiratory conditions.

Compound	Drought		Active photorespiration
	WT	*Ljgln 2-2*	WT	*Ljgln 2-2*
kaempferol-3,7-di-O-rhamnoside^a^, ^b	1.35±0.27^*	1.61±0.60^*	1.05±0.11	1.10±0.38
kaempferol-3-O-glucosyl-7-O-rhamnoside^a^, ^b	1.22±0.19	1.55±0.78	0.96±0.18	1.01±0.30
kaempferol-3-O-galactosyl-7-O-rhamnoside^b	1.36±0.36^*	1.48±0.59	1.14±0.28	0.97±0.31
kaempferol-3-O-glucosyl (1-2)-galactoside-7-O-rhamnoside^a^, ^b	1.09±0.28	1.54±0.68	0.96±0.20	0.73±0.29
kaempferol-3-O-glucosyl (1-2)-glucoside-7-O-rhamnoside^a^, ^b	2.53±1.08^**	1.77±0.74^*	0.93±0.32	0.82±0.26
kaempferol-6-deoxyhexose^b	1.22±0.58	1.51±0.61	0.85±0.44	1.05±0.39
Total kaempferol (after acid hydrolysis)	1.37±0.31^*	1.24±0.21^*	1.07±0.30	1.31±0.53
Quercetin-6-deoxyhexose, -hexose^b	20.81±9.13^**	1.76±0.85^*	0.99±0.65	1.08±0.51
Quercetin-6-deoxyhexose, -hexose^b	15.33±9.49^**	1.62±1.31	1.23±0.83	3.29±1.92^*
Quercetin-6-deoxyhexose, 6-deoxyhexose^b	8.78±6.24^**	1.45±0.87	0.96±0.64	1.19±0.70
Total quercetine (after acid hydrolysis)	11.68±4.02^**	2.63±0.50^**	0.86±0.45	1.56±0.54^*
flavonol-6-deoxyhexose-hexose ^b	1.46±0.79	1.39±0.59	0.88±0.38	1.21±0.52
p-coumaric acid	0.33±0.16^*	0.98±0.26	1.03±0.37	1.26±0.30
p-ferulic acid	0.81±0.52	1.31±0.74	1.16±0.51	1.13±0.48
Simple phenylpropanoid	0.44±0.25^**	0.96±0.56	1.03±0.38	1.26±0.47
Vestitol	1.20±0.35	2.08±0.52^**	1.24±0.15^*	8.94±4.13^**
Total tannins	1.02±0.10	1.20±0.28	1.24±0.23	1.19±0.10

The changes in the relative levels of phenolic compounds in the two genotypes as a consequence of drought or active PR are reported as the ratio between metabolite levels under control conditions (high CO₂, normal watering) and metabolite levels under stress conditions. Total crude extracts from leaves were obtained in 50% methanol and analyzed by HPLC as described in materials and methods, with the exception of vestitol, that due to its low polarity was quantified in leaf extracts obtained in 100% methanol. The different compounds were identified in HPLC chromatograms employing DAD detector, tannins were determined spectrophotometrically. Identities of compounds were verified by

NMR or

LC/ESI-MS.

For the compounds in italics it was not possible to determine their accurate chemical structure. Significant difference between levels in mutant and WT at

p < 0.05 or

^**

p < 0.01 (n = 4) according to Student's t-test.

Data are the mean ± S.D. of six independent biological replicates.