Study on the Isolation and Activity of Alcohol-soluble Compoments from Royal Jelly
|Course||Of Food Science|
|Keywords||Royal jelly Separation Antioxidation Tyrosinase Antibacterial|
Royal Jelly is of great nutrition and regarded as human ideal health food which possessseveral pharmacological activities include immunomodulatory effects, antiaging activity,antihypercholesterolemic activity, antitumor activity and other health functions. But now therelationship between chemical composition in royal jelly and function is not yet clear. In thispaper, we isolated and purified alcohol-soluble components in royal jelly to explore itsantioxidant activity, inhibitory capability against tyrosinase and antibacterial activity, in orderto provide theoretical basis for further development of royal jelly.The royal jelly was extracted with95%ethanol and then roughly divided into four partsby MCI-Gel column: water eluted fraction,30%ethanol eluted fraction,50%ethanol elutionfraction and70%ethanol elution fraction. After ODS column separation and purification wegot nine compounds: adenosine monophosphate (AMP), adenosine diphosphate (ADP),10-(10′-hydroxydecanoyloxy)-2-decenoic acid,9-amino-2-nonylketone and3,10-dihydroxydecanoic acid (3,10-DDA),10-hydroxy decenoic acid(10-HDA),10-hydroxy decanoicacid(10-HDAA),9-hydroxy decanoic acid(9-HDAA),8-hydroxy decanoic acid (8-HDAA).1,1-diphenyl-2-picrylhydrazyl free radicals (DPPH) and the total antioxidant capacityki（tT-AOC）were used to study the antioxidation of Royal Jelly. The results showed that thealcohol-extracted royal jelly had the highest total antioxidant capacity and DPPH scavengingactivity, of which the water and30%alcohol eluted fractions from MCI chromatographiccolumn had significantly higher antioxidant activities (p<0.05). What’s more, AMP, ADP,3,10-DDA which were isolated from the two fractions had the higher antioxidation than10-HDA. The results also showed IC50values for DPPH scavenging activity of AMP, ADP,3,10-DDA and10-HDA were at6.27mg/mL,8.82mg/mL,9.15mg/mL,9.63mg/mL,respectively.L-tyrosine was used as a substrate to study the effect of royal jelly against mushroomtyrosinase (monophenols activity). The results showed that the alcohol-soluble royal jellyexerted good inhibition of tyrosinase and in which the inhibition of50%and70%ethanolelution parts were stronger, the inhibition rates were80.29%,86.71%. The IC50value of10-HDA,10-HDAA and9-HDAA which were separated from the two parts were at1.12mg/mL,1.31mg/mL,1.57mg/mL. But the RJ precipitates after alcohol extract and the watereluted fraction from MCI column activated tyrosinase.The results of antibacterial activity research showed that the alcohol-soluble royal jellyhad certain inhibition against Staphylococcus aureus, Listeria monocytogenes, Salmonellaenteritidis, Shigella dysenteriae, Escherichia coli., Pseudomonas aeruginosa, Candidamycoderma and Trichophyton rubrum and showed no effect on Aspergillus niger, Aspergillusflavus. Among these bacterias, Trichophyton rubrum was the most sensitive to theethanol-extract royal jelly which the MIC value was1.25mg/mL, followed by Escherichiacoli and Pseudomonas aeruginosa Pseudomonas, MIC values were2.5mg/mL. Except for thewater elution part from MCI chromatographic column,30%,50%,70%ethanol elution partshad antimicrobial activity, and the effect of inhition depended on the types and content ofmedium-chain fatty acids in royal jelly.