Cost-Effective HPLC Method for Identification of Rosmarinic Acid in Methanol Extract of Ocimum Basilicum

Prescribing herbal remedies is now becoming common by many practitioners, who propose herbal treatments along with conventional medicine systems to treat various ailments considering their synergistic effects. Rosmarinic acid is a potent phenolic compound and caffeic acid derivative. It has many miraculous biological activities. Anti-allergic, anti-angiogenic, anti-depressant, anti-inflammatory, antitumor, anti-microbial activity, and antiviral effect of rosmarinic acid has already been documented in previous literature. It is widely present in many formulations because of its hepatoprotective and antioxidant effect. This study aimed to develop and validate a RP-HPLC method for the standardization of O. basilicum L. raw material and extracts by using rosmarinic acid as a marker. The study also aimed to quantify the rosmarinic acid content in the methanol extract of O. basilicum leaves. A simple and cost-effective High Pressure Liquid Chromatography (HPLC) method for determining rosmarinic acid in Ocimum basilicum plant extract has been developed and validated. Methanol-water-orthophosphoric acid in the ratio of 95:5:1 was used as the mobile phase using a C18 reversed-phase column for the HPLC method. Signals were detected at 254 nm. The rosmarinic acid content was found to be 4.2 mg/10 mg of the plant extract. The method is sensitive and reproducible and ideal for quick routine analysis and can be employed for detecting rosmarinic acid in other herbs. Despite the availability of literature on the medicinal properties of this plant and its chemical constituents, only a limited number of papers have been published on the determination of the rosmarinic acid in Ocimum basilicum plant using RP-HPLC. Moreover, this is the first report that quantifies rosmarinic acid in the plant extract by HPLC without using expensive columns and complex buffer systems that deteriorate the chromatographic columns and in turn, enhance the cost of the used process.