Date of Award


Document Type


Degree Name

Doctor of Philosophy (PhD)

First Advisor

Sang, Shengmin


The objective of this study was to investigate the preventive effects of rosemary leaf extract (RE) and its active components on prevention of weight gain and associated metabolic disorders in high-fat-fed mice; determine the effective doses of the chief compound in RE to reduce weight gain and hyperglycemia; and try to understand the underlying anti-obesity mechanism. For this purpose, commercial RE with 45% carnosic acid (CA) was enriched with CA to 80%. Animals were given low-fat diet (LFD), high-fat diet (HFD), high fat with 0.50% RE (enriched with 45% CA, RE#1), high fat with 0.28% w/w RE (enriched with 80% CA, RE#2H), and high fat with 0.14% w/w RE (enriched with 80% CA, RE#2L) for 16-week periods. Physiological and biochemical parameters were monitored. Treatment with CA, dose dependently, induced a significant reduction of weight and fat mass gain which it was associated with an increase of fecal lipid excretion. Likewise, hypercholesterolemia, fasting glycaemia, and insulin resistant were improved by CA treatments. Hepatic triglyceride levels, correspondingly, were decreased in CA-treated mice. In conclusion, the results from this study demonstrate that consumption of the RE that is rich in CA, dose dependently can limit weight gain induced by a high-fat diet and protect against obesity-related metabolic disorders.