Many Americans are either currently taking, or have recently taken, non-prescription dietary supplements. These supplements claim to help prevent or relieve any number of ailments, but are not regulated by any governing body. One common use of dietary supplements is to aid in weight loss. Synephrine, the most abundant active component in bitter orange (Citrus aurantium L.) extracts, became a regular ingredient in weight loss supplements after the 2004 ephedra ban. The initial goal of this research was to use reverse phase high performance liquid chromatography (HPLC) to determine the synephrine content of five dietary supplements and compare to the reported content on the label. However, due to difficulties I encountered with the HPLC instrument, I instead used NanoDrop Spectrophotometry to analyze synephrine content. This technique was not as precise as HPLC, but data were obtained that indicated the supplements contained significantly less synephrine than the standard (1-Way ANOVA, F42.1=60.042, P=< 0.001). Additionally, my analysis indicated that the supplements had a lower concentration of synephrine than what was reported on their labels.
","abstract_html":"<p>Many Americans are either currently taking, or have recently taken, non-prescription dietary supplements. These supplements claim to help prevent or relieve any number of ailments, but are not regulated by any governing body. One common use of dietary supplements is to aid in weight loss. Synephrine, the most abundant active component in bitter orange (<em>Citrus aurantium L.</em>) extracts, became a regular ingredient in weight loss supplements after the 2004 ephedra ban. The initial goal of this research was to use reverse phase high performance liquid chromatography (HPLC) to determine the synephrine content of five dietary supplements and compare to the reported content on the label. However, due to difficulties I encountered with the HPLC instrument, I instead used NanoDrop Spectrophotometry to analyze synephrine content. This technique was not as precise as HPLC, but data were obtained that indicated the supplements contained significantly less synephrine than the standard (1-Way ANOVA, F42.1=60.042, P=< 0.001). Additionally, my analysis indicated that the supplements had a lower concentration of synephrine than what was reported on their labels.</p>","abstract_has_math":false,"creators":["Newell, Martha L."],"institution":null,"degree_name":"Biology","degree_level":"Thesis","degree_discipline":"Biology","degree_department":null,"school":null,"contributors":["Dr. Jennifer Newbrey","Dr. Julie Ballenger","Dr. Cindy Ticknor"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2013,"date_issued":"2013-07-01T07:00:00Z","date_published":"2013-07-01T07:00:00Z","updated_at":"2026-07-24T01:44:55Z","subjects":["Dietary Supplements","Weight Loss","Bitter Orange","Citrus aurantium L.","HPLC","Synephrine","Biology","Dietetics and Clinical Nutrition"],"languages":["English"],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://csuepress.columbusstate.edu/theses_dissertations/98","outbound_label":"Repository record","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Dr. Jennifer Newbrey","Dr. Julie Ballenger","Dr. Cindy Ticknor"]},{"key":"dc:creator","label":"Author","values":["Newell, Martha L."]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.available","label":"Dc Date Available","values":["2015-10-12T07:00:00Z"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Biology"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Thesis"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Biology"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Dietary Supplements","Weight Loss","Bitter Orange","Citrus aurantium L.","HPLC","Synephrine","Biology","Dietetics and Clinical Nutrition"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["English"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://csuepress.columbusstate.edu/theses_dissertations/98"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["Many Americans are either currently taking, or have recently taken, non-prescription dietary supplements. These supplements claim to help prevent or relieve any number of ailments, but are not regulated by any governing body. One common use of dietary supplements is to aid in weight loss. Synephrine, the most abundant active component in bitter orange (Citrus aurantium L.) extracts, became a regular ingredient in weight loss supplements after the 2004 ephedra ban. The initial goal of this research was to use reverse phase high performance liquid chromatography (HPLC) to determine the synephrine content of five dietary supplements and compare to the reported content on the label. However, due to difficulties I encountered with the HPLC instrument, I instead used NanoDrop Spectrophotometry to analyze synephrine content. This technique was not as precise as HPLC, but data were obtained that indicated the supplements contained significantly less synephrine than the standard (1-Way ANOVA, F42.1=60.042, P=< 0.001). Additionally, my analysis indicated that the supplements had a lower concentration of synephrine than what was reported on their labels.
"]},{"key":"dc:title","label":"Title","values":["Analysis of Synephrine Content in Bitter Orange (Citrus aurantium L.) Dietary Supplements"]}]}],"canonical_facts":{"dc:contributor":["Dr. Jennifer Newbrey","Dr. Julie Ballenger","Dr. Cindy Ticknor"],"dc:creator":["Newell, Martha L."],"dc:date.available":["2015-10-12T07:00:00Z"],"dc:description.abstract":["Many Americans are either currently taking, or have recently taken, non-prescription dietary supplements. These supplements claim to help prevent or relieve any number of ailments, but are not regulated by any governing body. One common use of dietary supplements is to aid in weight loss. Synephrine, the most abundant active component in bitter orange (Citrus aurantium L.) extracts, became a regular ingredient in weight loss supplements after the 2004 ephedra ban. The initial goal of this research was to use reverse phase high performance liquid chromatography (HPLC) to determine the synephrine content of five dietary supplements and compare to the reported content on the label. However, due to difficulties I encountered with the HPLC instrument, I instead used NanoDrop Spectrophotometry to analyze synephrine content. This technique was not as precise as HPLC, but data were obtained that indicated the supplements contained significantly less synephrine than the standard (1-Way ANOVA, F42.1=60.042, P=< 0.001). Additionally, my analysis indicated that the supplements had a lower concentration of synephrine than what was reported on their labels.
"],"dc:identifier":["https://csuepress.columbusstate.edu/theses_dissertations/98"],"dc:language":["English"],"dc:subject":["Dietary Supplements","Weight Loss","Bitter Orange","Citrus aurantium L.","HPLC","Synephrine","Biology","Dietetics and Clinical Nutrition"],"dc:title":["Analysis of Synephrine Content in Bitter Orange (Citrus aurantium L.) Dietary Supplements"],"thesis:degree_discipline":["Biology"],"thesis:degree_level":["Thesis"],"thesis:degree_name":["Biology"]},"updated_at":"2026-07-24T01:44:55Z"}