**5.3 Spectroscopic techniques of phytochemical quantification**

Spectroscopic techniques such as ultraviolet (UV-visible), infrared (IR), mass spectroscopy, and nuclear magnetic resonance (NMR) provide sufficient information for quantitative as well as qualitative analysis of phytochemicals. Basically, depending on its structure, the organic molecule absorbs electromagnetic radiations in certain regions and produces a spectrum. The obtained spectrum helps in the identification and quantification of the molecule, since they are specific to functional groups [89].

The spectroscopic techniques include the following:


*Phytochemical Contents of Essential Oils from* Cymbopogon *Species: A Tropical Medicinal Plant DOI: http://dx.doi.org/10.5772/intechopen.105396*
