Volatile Oil Constiturnts Of SWeet Fennel Fruits Treated With Some Macro and Micro Nutrients Under Desert Conditions In Egypt

Abstract

Mature fruit and volatile oil of sweet fennel are used as flavoring agents in food products such as liqueurs, bread, pickles, pastries, and cheese. They are also used as a constituent of cosmetic and pharmaceutical products. Desert regions in Egypt are characterized by poor nutrients (macro and micro) and unfavorable environmental conditions which negatively affect aromatic plants including sweet fennel plants. The main objective of the present investigation was to study the effect of different levels of NP nutrients, trace elements and their interactions on the volatile oil extracted from sweet fennel fruits under these desert conditions. The interaction between NP and micro nutrients caused a pronounced increment in both volatile oil content and yield compared with the treatments of NP without micro nutrients. Twenty three constituents were identified in volatile oil extracted from fennel fruits, accounting for 98.3% – 100.0 % of total constituents, and belong to three chemical main classes. Oxygenated monoterpenes class was the major one (97.0% - 98.8%), the remaining fractions as monoterpene hydrocarbons (0.8% – 1.4%) and sesquiterpene hydrocarbons (0.1% - 0.3%) formed the minor classes. The main constituents of fennel fruits volatile oil as detected by GC/MS were trans-anethole (58% - 58.6%), estragole (21.0% - 21.4%) and fenchone (17.0% - 19.5%) which increased as NP level increase. NP + micro nutrients treatments resulted in higher values of main components compared with the treatments of NP alone.