Evaluation of Chemical, Functional, Spectral, and Thermal Characteristics of Sargassum wightii and Ulva rigida from Indian Coast

Table 4

FTIR absorption frequencies and functional group of Sargassum wightii and Ulva rigida.

Wavenumber		Functional group	Compounds	References
S. wightii	U. rigida
3859	—	OH-stretching	Alcohol	[31]
3740	3750			[31]
3669	—			—
—	3245			—
2372	—	C-O stretching	Phosphorous	[10]
1684	1631	C=O stretching, N=O asymmetric stretching	Ester, pectin, amide	[32]
1527	1527	C=C stretching	Lignin	[32]
—	1417	C-O stretching, O-H bending	Cutin	[33]
—	1219	S=O stretching, C-O stretching	Sulphates, phenols	[33]
1023	1023	S=O stretching	Starch and polysaccharides	[33]
—	842	C-H bending	Glucose, galactose	[33]
699	666	C-S stretching, C=S stretching	Sulphates	[33]