Oleanolic acid(OA) and ursolic acid(UA) are isomeric triterpenic acids and only one methyl’s position is different between them.OA and UA always exist in the same plant,so it is difficult to separate them when determ...Oleanolic acid(OA) and ursolic acid(UA) are isomeric triterpenic acids and only one methyl’s position is different between them.OA and UA always exist in the same plant,so it is difficult to separate them when determining contents by RP-HPLC.In this study,a very simple mobile phase for HPLC was developed to simultaneously determine UA and OA,and the factors affecting separation were also discussed.The mobile phase is methanol:water(95:5) with flow rate 0.4 mL/min.The retention time for OA and UA was 20.58 and 21.57 min,respectively,the resolution was 1.61.The average contents of OA and UA of three Loquat leaves sets were 1.4 mg/g and 5.6 mg/g,respectively.Regarding the HPLC,we found that changing mobile phase,adjusting the pH value or adding ion-pairing agent could not affect the separation between UA and OA greatly.While adjustment of the flow rate and column temperature could improve the resolution greatly.展开更多
Background: The association between uric acid (UA) with metabolic syndrome (MS) has been researched more in adults than in adolescents. In fact, this association is not completely understood among adolescents. Objecti...Background: The association between uric acid (UA) with metabolic syndrome (MS) has been researched more in adults than in adolescents. In fact, this association is not completely understood among adolescents. Objectives: The purpose of this study was to explore the association between UA with MS. Methods: A cross-sectional sample of 742 Kuwaiti adolescents (303 males and 439 females) who were apparently healthy, chosen from randomly selected schools were used for the study;four intermediate (two males and two females) and four secondary (two males and two females) schools. Results: The results of the study showed the UA level was highly associated with MS, especially among males. UA was significantly associated with each of the six parameters of MS. Conclusions: The level of uric acid among the adolescent was high and it was significantly associated with MS and gender. Dietary interventions are necessary to reduce UA and the parameters of MS among the adolescents.展开更多
文摘Oleanolic acid(OA) and ursolic acid(UA) are isomeric triterpenic acids and only one methyl’s position is different between them.OA and UA always exist in the same plant,so it is difficult to separate them when determining contents by RP-HPLC.In this study,a very simple mobile phase for HPLC was developed to simultaneously determine UA and OA,and the factors affecting separation were also discussed.The mobile phase is methanol:water(95:5) with flow rate 0.4 mL/min.The retention time for OA and UA was 20.58 and 21.57 min,respectively,the resolution was 1.61.The average contents of OA and UA of three Loquat leaves sets were 1.4 mg/g and 5.6 mg/g,respectively.Regarding the HPLC,we found that changing mobile phase,adjusting the pH value or adding ion-pairing agent could not affect the separation between UA and OA greatly.While adjustment of the flow rate and column temperature could improve the resolution greatly.
文摘Background: The association between uric acid (UA) with metabolic syndrome (MS) has been researched more in adults than in adolescents. In fact, this association is not completely understood among adolescents. Objectives: The purpose of this study was to explore the association between UA with MS. Methods: A cross-sectional sample of 742 Kuwaiti adolescents (303 males and 439 females) who were apparently healthy, chosen from randomly selected schools were used for the study;four intermediate (two males and two females) and four secondary (two males and two females) schools. Results: The results of the study showed the UA level was highly associated with MS, especially among males. UA was significantly associated with each of the six parameters of MS. Conclusions: The level of uric acid among the adolescent was high and it was significantly associated with MS and gender. Dietary interventions are necessary to reduce UA and the parameters of MS among the adolescents.
