All pollens show broadband at ~3332cm -1 corresponding to O-H stretching vibration from water , and two strong peaks at 2919 and 2858 cm -1 (with some difference for the samples of El-Oued (P13) region which have an additional peak at 2777 cm -1 ), these peaks are assigned to the C-H stretching vibrations of carbohydrates and sugars , respectively.