Royal jelly

Royal jelly is a creamy, whitish, strongly acidic secretion from the mandibular and hypopharyngeal
(cephalic) glands of Apis mellifera (Hymenoptera, Apidae) nurse bees, and is important in the sexual differentiation and longevity of the queen bee.
Pure royal jelly is usually presented in the form of cream, capsules, or powder/flakes (freeze-dried);
additionally, it is an ingredient in many products.
Royal jelly contains sugars, proteins, fatty acids, amino acids, vitamins, salts and trace elements.
The average water content of royal jelly is 60-70%.
Crude protein (49-87 kDa) constitutes 12-15% (or about 50% of the dry mass), sugars 10-16% and lipids 3-7%. Proteins in royal jelly largely belong to one protein family designated MRJP (major royal jelly proteins, about 90% of proteins)(apalbumins).
Components of royal jelly reported to be biologically active include va rious proteins and peptides, the fatty acid 10-hydroxy-2-decenoic acid (10-HDA), and unidentified components with estrogenic activity.
The composition of royal jelly is reported to vary with seasonal and regional conditions (Bincoletto et al., 2005; Fontana et al., 2004; Sver et al., 1996)
.