Total Protein and 10-Hydroxy-2-Decenoic Acid Content, In Vitro Bioaccessibility, Antibacterial, and Antidiabetic...

Royal jelly has received interest as a functional food. Consumers are interested in functional foods, particularly from natural sources. Royal jelly's protein and 10-hydroxy-2-decenoic acid content and biological activities are affected by a number of factors. This study aimed to evaluate the protein and 10-hydroxy-2-decenoic acid content, in vitro antibacterial, antidiabetic properties, and bioaccessibility of royal jelly collected at 72 and 144 h after larval grafting; and were examined using standard methods. Royal jelly collected at the 72 h showed higher protein (12.99%) and 10-hydroxy-2-decenoic acid (3.39%) content. The bioaccessibility of protein and 10-hydroxy-2-decenoic acid content in royal jelly in the gastric stage was found to be lower compared to intestinal stage for both 72 and 144 h. The inhibitory concentration (IC₅₀) was highest against Bacillus cereus (33.15%), while the lowest potency was observed in Salmonella enterica (50.10%) at 72 h. The high IC₅₀ potency was found at 144 h in Bacillus cereus (49.09%), and the lowest was in Listeria monocytogenes (63.25%). The maximal inhibition of α-amylase (75.33%) and α-glucosidase (75.93%) was observed to have significant difference (p < 0.05) in royal jelly collected at 72 h. For royal jelly collected at 72 and 144 h, the IC₅₀ values of α-amylase were 24.70% and 33.87%, respectively, while the IC₅₀ values of α-glucosidase were 2.81% and 12.27%. Therefore, royal jelly collected at 72 h possesses high protein and is rich in 10-hydroxy-2-decenoic acid content. It is also more bioaccessible, and exhibits strong antibacterial and antidiabetic effects, which are attributed to the variation in harvesting time.