Simultaneous quantitation of oleanolic and ursolic acids by RP-HPLC-DAD on active ingredient from Tabebuia hypoleuca...

Area of Science:

• Phytochemistry
• Analytical Chemistry
• Pharmacognosy

Background:

• The genus Tabebuia is utilized in traditional medicine across tropical and subtropical regions.
• Tabebuia hypoleuca, endemic to Cuba, exhibits antitumor properties, attributed to its high triterpenic acid content.
• Oleanolic acid (OA) and ursolic acid (UA) are key triterpenic acids found in Tabebuia species.

Purpose of the Study:

• To develop and validate a reversed-phase high-performance liquid chromatography (RP-HPLC) method with diode array detection (DAD).
• To enable simultaneous quantitation of oleanolic acid (OA) and ursolic acid (UA) in Tabebuia hypoleuca leaf extracts.
• To establish OA and UA as potential quality control markers for Tabebuia hypoleuca active pharmaceutical ingredients (APIs).

Main Methods:

• Utilized a C18 column with a mobile phase of methanol and water (95:5 v/v) at a flow rate of 0.4 mL/min.
• Detection was performed at 210 nm, with retention times of 16.371 ± 0.045 min for OA and 16.943 ± 0.052 min for UA.
• Method validation included linearity, limit of detection (LOD), and limit of quantification (LOQ) assessments.

Main Results:

• The developed RP-HPLC-DAD method achieved a peak resolution of 1.29 between OA and UA.
• Average contents were 102.93 mg/g for OA and 244.28 mg/g for UA in the ethyl acetate extract.
• Linearity was established in ranges of 10-700 μg/mL for OA (r²=0.9924) and 5-1000 μg/mL for UA (r²=0.9865), with specific LOD and LOQ values determined for each compound.

Conclusions:

• The validated RP-HPLC-DAD method is accurate, specific, precise, and reproducible.
• OA and UA can be reliably quantified and used as markers for quality assessment of Tabebuia hypoleuca extracts.
• This method offers a simple and rapid quality-control procedure for medicinal plant extracts containing similar triterpene profiles.