Table 3.

UV−vis, retention time, and mass spectrometry characteristics of the polyphenolic compounds tentatively identified in the four microalgae species.

Species	Peak (N°)	Rt (min)	λMax(nm)	[M − H]−	Fragment	Compound Identification	References
Phaeodactylum tricornutum	1	1.38	228, 260	153.1	-	Protocatechuic acid	[25]
	2	1.60	295, 324	179.2	-	Caffeic acid	[12]
	3	2.76	267, 354	683.4	341.5	Caffeic acid hexoside dimer	[26]
	4	8.85	251, 380	281.3	-	Dimethoxyflavone	[27]
	5	9.06	257	326.3	-	p-coumaroyl tyrosine	[28]
Nannochloris sp	1	1.38	228, 260	153.1	-	Protocatechuic acid	[25]
	6	1.60	217, 269	277.4	-	Caffeoyl-coumaroyl-quinic acid	[29]
	7	2.53	273	289.3	-	Catechin	[30]
	4	6.92	251, 380	281.3	-	Dimethoxyflavone	[27]
	8	9.95	-	285.2	-	Kaempferol	[31]
Tetraselmis suecica	1	1.36	228, 260	153.1	-	Protocatechuic acid	[25]
	2	1.60	295, 324	179.2	-	Caffeic acid	[11]
	9	4.66	263, 339	341.3	-	Caffeoyl glucoside	[32]
	4	6.93	251, 380	281.3	-	Dimethoxyflavone	[27]
	5	7.28	257	326.3	-	p-coumaroyl tyrosine	[28]
	10	47.99	330	577.5	269	Apigenin-O-rutinoside	[33]
	11	49.67	249, 330, 375	611.6	594	Rhamnosyl hexosyl-methyl-quercetin	[34]
Nannochloropsis gaditana	1	1.39	228, 260	153.1	135	Protocatechuic acid	[25]
	2	1.60	295, 324	179.2	135	Caffeic acid	[11]
	12	3.02	247	301.2	227	Quercetin	[35,36]
	9	4.66	263, 339	341.3	323	Caffeoyl glucoside	[32]
	13	6.82	257, 360	385.4	348	Feruloylglucaric acid	[26]
	5	7.18	257	326.3	-	p-coumaroyl tyrosine	[28]
	10	47.99	330	577.5	269	Apigenin-O-rutinoside	[33]
	11	49.68	249, 330, 375	611.6	594	Rhamnosyl hexosyl-methyl-quercetin	[34]