Bachlien Dang

Document Type


Date of Award



College of Science, Engineering, and Technology (COSET)

Degree Name

MS in Chemistry

First Advisor

Professor Dr. Yuanjian Deng


The Macartney rose (Rosa bracteata) is a noxious evergreen shrub, which grows in mild climates. This is a rose that will climb trees and smoother small buildings if given a chance! It is climbing and trailing from large clumps which may merge, forming impenetrable thickets. Its stems have thorns, which are nasty, hooked affairs, and leaves that are oval shape with serrate margin. The rose is also called "Fragrant White Climbing Rose". It blooms in late spring with smaller repeats throughout the rest of summer, and fruits ripen in late fall. The plant is a troublesome plant that grows abundantly in Southeast Texas, creating economic problems for agricultural workers and providing ornamental uses for others. Cattle generally graze and eat most vegetation and plants within their reach; however, they consistently avoid the rose, suggesting that toxic constituents may be present in the woody plant. The proposed work seeks to determine the active constituents of the rose that are toxic. The stems, leaves, fruits, seeds, and roots of the rose were ground separately and then extracted with either methanol or hexane. The fruit extract was further separated with other five solvents, hexane, dichloromethane, ethyl acetate, methanol, and water in sequence. Five-tenth gram of each methanol extract were dissolved in 5 ml of dimethyl 2 sulfoxide. Exactly 50 f.11 of the DMSO solution was injected into a vial that contained 5� ml seawater with 10 Brine shrimps. For control vials, the mixture contained only 50 ul of dimethyl sulfoxide and 5 m1 the seawater without the extract. The acute toxicity was evaluated based on the percentage survival of the shrimps in the extract seawater at 6 and 24 hours, respectively. The result from the shrimp test indicated that the fruit extract and its ethyl acetate fraction were the most toxic. With the aid of thin layer chromatography, qualitative chemical analysis, and Ge/MS measurements, glycin, furandione, tributylammine and tannins have been found to be present only in the fruit extract and its ethyl acetate fraction that are account for the toxicity of the rose