Screening of Fruits of Seven Plants Indicated for Medicinal Use in Iraq

INTRODUCTION: Coumarins exert many biological effects in humans, animals, and plants, which make the evaluation of their biological activities and study of their role in ethnomedicine highly valued. OBJECTIVES: Here, we selected seven plants which have ethnopharmacological use as antimicrobial in Iraq and the aims were to quantify the two structural isomers bergapten and methoxsalen in their seeds, to evaluate the antibacterial activities against several clinical isolates, and to isolate bergapten and methoxsalen from Ammi majus. MATERIALS AND METHODS: Seven plants were extracted by petroleum ether (PE) and ethanol (EtOH). Bergapten and methoxsalen were separated and purified by preparative thin-layer chromatography. Quantification of the furanocoumarins has been conducted by high-performance liquid chromatography, and all the plant extracts and pure compounds were checked for antibacterial activities utilizing alamar blue microplate assay. RESULTS: Cuminum cyminum was deprived of bergapten and methoxsalen and methoxsalen was not detected from Apium graveolens. Bergapten was abundant in PE more than in EtOH; on the other hand, EtOH was rich in methoxsalen. The separation of the two structural isomers was performed using normal phase chromatography and ultraviolet light as an indicator. All extracts showed weak to moderate antibacterial activities against Gram-positive isolates which were more sensitive than the negative ones. C. cyminum extract was least active, uncover the antibacterial role of bergapten and methoxsalen. CONCLUSION: These findings support the medicinal use of seeds of seven plants from Apiaceae family and quantify the two pharmacologically important furanocoumarins (bergapten and methoxsalen). SUMMARY: This study was conducted to evaluate the antibacterial activities of seven plants seeds used in local medicine in Iraq. High-performance liquid chromatography was used to quantify bergapten and xanthotoxin in non-polar and polar extracts of these seeds. This study supports the medicinal use of these plants and clarifies the role of bergapten and xanthotoxin in antibacterial activities of these plants. Abbreviations used: EtOH: Ethanol; MIC: Minimum inhibitory concentration; PE: Petroleum ether; Rf: Retardation factor; Rt: Retention time.