The strong band at 1620 cm−1 is attributed to the C=C stretch in aromatic rings attributed in polyphenols and also may correspond to C=O stretch in amides.
The increased production of mono-aromatics was attributed to the oligomerization and aromatization of pyrolysis reaction intermediates occurring on the acid sites of Al-SBA-15.
Sambha Mahsuri and Swarna clustered for the other aromatic and mouthfeel/taste attributes, and as noted above, in a comparison of the two varieties, none of these attributes were significantly different.
Similarly, cytotoxic activities of essential oils from various aromatic plants were attributed to specific components of the oils [ 36, 37].
From propolis extract, typical bands at 1165 cm-1, attributed to C O and C OH vibration, at 1434 cm-1, attributed to C H vibration, at 1512, 1598 and 1630 cm-1, attributed to aromatic ring deformations and at 1681 cm-1, attributed to C = O stretching of flavonoids and lipids, found in propolis ethanolic extract.
The plant species attributes its aromatic properties to the presence of essential oil rich in monoterpenes and sesquiterpenes and volatile constituents such as menthol, menthone, carvacol, pulgone and isomenthone, imparting characteristic mint flavor.
The peak at 1123 cm−1 is attributed to aromatic C H inplane bending mode [39].
The 1614 and 1525 cm−1 peaks are attributed to aromatic ring C-C stretching.
The group of closely related bands in the range of 1496 to 1525 cm−1can be attributed to aromatic C=C stretching.
Decreasing of aromatic intermediates' concentrations is attributed to the further oxidation by hydroxyl radicals to aliphatic acids and CO2 (Yavuz et al. 2007; Bach et al. 2010).
