Royal jelly is a natural viscous, milky-white product which is secreted from special glands of young worker honey bees (Apis mellifera L.) used to feed queen larvae and the queen bee throughout its life. It can be used as a dietary complement because of its composition, and also it contains a large number of bioactive substances such as peptides, flavonoids, fatty acids and also 10-hydroxy-2-decenoic acid (10-HDA). The variation in chemical compounds of royal jelly depends on some factors such as floral sources, queen cup types and harvesting time. In this study, the effect of harvesting period (April, May, June, July and August) on physicochemical properties and 10-HDA content in royal jelly collected from different producers in Turkey. The total solid contents as well as protein contents of royal jelly significantly changed depend on the harvesting period, but no alteration in pH value. The maximum means of total phenolic content and antioxidant activity were found in samples harvested in July. 10-HDA content varied from 0.91% to 2.05%, with a mean of 1.38%. A significant effect of month in 10-HDA content was found, and the highest mean value observed in June.
Royal jelly, harvesting period, 10-hydroxy-2-decenoic acid (10-HDA), chemical properties, bioactive properties