Chemical Characterization and Biological Properties of Royal Jelly Samples From the Mediterranean Area

Abstract

Royal jelly (RJ) is a bee product that has high nutritional value and is beneficial for the human health, earning importance as a functional food. Thus, the characterization of its main biological properties is with high importance. In this work, 6 RJ samples obtained in Morocco, Portugal, and Spain were evaluated in terms of total phenol and flavone/flavonol contents; total protein; 10-hydroxy-2-decenoic acid (10-HDA); volatiles composition; antioxidant and anti-inflammatory properties; and inhibition of tyrosinase, xanthine oxidase (XO), and acetylcholinesterase (AChE) activities. Total phenolic content ranged from 3 to 9 mg gallic acid equivalent/g RJ, and flavone/flavonol content from 0.1 to 0.5 mg quercetin equivalent/g RJ. 10-Hydroxy-2-decenoic acid content varied from 0.9% to 1.2% and total protein from 5.5% to 29.7%. Gas chromatography-flame ionization detector and gas chromatography-mass spectrometry analysis showed RJ volatiles dominated by linolenic acid, 2-decenoic acid, and octanoic acid in variable amounts. The antioxidant activity was monitored through nitric oxide (NO) scavenging activity and hydrogen peroxide (H 2 O 2 ) scavenging capacity, where the IC 50 ranged from 2.3 to 3.4 and 0.2 to 1.5 mg/mL, respectively. Anti-AChE activity IC 50 ranged from 0.7 to 4.6 mg/mL, while XO inhibition IC 50 ranged from 3.3 to 11.9 mg/mL. The results showed that phenols and flavonoids highly contributed to the RJ biological properties in contrast to 10-HDA and proteins.Honeybees, Apis mellifera, are a source of a variety of precious and valuable natural products with health-promoting bioactive compounds including honey, bee bread, bee venom, bee pollen, propolis, and royal jelly (RJ). 1 Royal jelly is a milky-white and strongly acidic (pH 3.1-3.9) fluid produced by the hypopharyngeal and mandibular glands of A. mellifera L. young worker honeybees (called nurses). 2 Royal jelly serves as the most important part of honeybee larvae diet, playing a major role in caste differentiation. It is the food given to all young larvae of workers and drones in their maturation process, whereas the queen honeybee is fed RJ for her entire life cycle and nurse honeybees are fed RJ for only 3 days after which worker larvae are fed a mixture of RJ, pollen, and honey. 3 Royal jelly was found to be mainly composed of water (50%-70%), proteins (9%-18%), carbohydrates (7%-18%), lipids (3%-8%), mineral salts (1.5%), vitamins, polyphenols, enzymes, and hormones. 4 A unique and chemically interesting feature in RJ is its lipidic fraction, where 80% to 85% are uncommon short chain hydroxy and dicarboxylic free fatty acids, with 8 to 12 carbon atoms. 2 The main compound,

Pharmaceutical Prospects of Bee Products: Special Focus on Anticancer, Antibacterial, Antiviral, and Antiparasitic Properties

“…Royal jelly (bee's milk) is a viscous whitish to yellow jelly-like substance secreted by the mandibular and hypopharyngeal glands of worker honeybees [72,73]. It is slightly soluble in water with a strong smell and sour or sweet flavor and a pH of 3.1-3.9 [74]. Royal jelly plays an important role in honeybee larvae diet.…”

“…hydroxybenzoic acid, 4-hydroxyhydrocinnamic acid, octanoic acids, 2-hexenedioic acid and its esters, dodecanoic acid and its ester, 1,2-benzenedicarboxylic acid, and benzoic acid) and other phenolic compounds such as hydroquinone, methyl salicylate, 2-methoxyp-cresol, 2-methoxyphenol, and pyrocatechol [48,76]. The TPC and TFC range from 3 to 9 mg GAE/g and 0.1 to 0.5 mg QE/g royal jelly, respectively [74]. In addition, royal jelly contains hormones (prolactin, testosterone, estradiol, and progesterone), minerals (Cu, Fe, K, Mg, and Zn), and vitamins (B1, B2, B3, B5, B6, B9 and provitamin A) [79].…”

“…Royal jelly consists of flavanones (pinobaskin, pinocembrin, hesperidin, naringin, and naringenin), flavones (acacetin, apigenin, chrysin, and luteolin), flavonols (fisetin, galangin, isorhamnetin, kaempferol, quercetin, and rutin), phenolic acids (caffeic acid, gallic acid, 4-hydroxy-3-methoxyphenylethanol, 4-hydroxybenzoic acid-methyl ester, 4hydroxybenzoic acid, 4-hydroxyhydrocinnamic acid, octanoic acids, 2-hexenedioic acid and its esters, dodecanoic acid and its ester, 1,2-benzenedicarboxylic acid, and benzoic acid) and other phenolic compounds such as hydroquinone, methyl salicylate, 2-methoxyp-cresol, 2-methoxyphenol, and pyrocatechol [48,76]. The TPC and TFC range from 3 to 9 mg GAE/g and 0.1 to 0.5 mg QE/g royal jelly, respectively [74]. In addition, royal jelly contains hormones (prolactin, testosterone, estradiol, and progesterone), minerals (Cu, Fe, K, Mg, and Zn), and vitamins (B1, B2, B3, B5, B6, B9 and provitamin A) [79].…”

Health Promoting Properties of Bee Royal Jelly: Food of the Queens

“…There are few references to volatile compounds (VC) in RJ, being the least studied and identified components of it [ 13 , 65 , 98 , 99 , 100 ]. However, the mixture of these various VC directly affects the taste and quality odor of the RJ [ 98 , 99 ].…”

Royal Jelly as a Nutraceutical Natural Product with a Focus on Its Antibacterial Activity

“…Due to the fact that it possesses various pharmacological properties, RJ is employed as a natural agent in medical fields, as well as in cosmetic and food industries [1]. Among these, antimicrobial [10,11], antioxidant [12], anti-inflammatory [3], antitumoral [13], antiviral [14], immunomodulatory [15], neuroprotective [13], antiaging [16] properties were reported. Data in the current literature state that RJ has the highest market value among bee products [1].…”