Abstracts
Background: The benefits of flowering plants to human go beyond
beautifying environments and oxygen replenishing. Generally, plants are
nature’s gifts that contain chemicals that have many industrial applications.
Although, many of them are yet to be exploited. Understanding the chemistry of plants’ extracts would be of great help to solving the problem of under- utilizing these plants. Therefore, this research was designed to evaluate the chemical components, cytotoxicity, antimicrobial (antibacterial and antifungal) and antioxidant properties of essential oils (EOs) hydrodistilled from the leaves and flower of Pink Plumeria rubra.
Methodology: Gas chromatography coupled with Mass spectrometry
(GC/MS), Brine Shrimps Lethality Test (BSLT), Agar diffusion method and
DPPH radical scavenging assay were used to analyse and evaluate the
biological activities of the essential oils. The results were subjected to
descriptive and statistical analysis.
Results: Both oils have greater proportion of non-terpenes than terpenes. The leaf and flower oils were dominated by pentadecanal (51.2%) and 1-docosanol (34.6%) respectively. The BSLT gave LC50 of 2.5636ppm (leaf) and 24.8631ppm (flower), indicating they are toxic and hence biologically active. Both oils possess insignificant antibacterial activity but notable anti-fungi potential when compared with standard drug Ketoconazole. Statistical analysis showed no significant difference in the activity of both leaf and Ketoconazole. The EOs have moderate free-radical scavenging ability (IC50, Leaves, 528.23ppm; Flower,299.17ppm) compared with that of α-Tocopherol (81.54ppm).
Conclusion: This study revealed the chemistry of the EOs and their potentials as a natural antioxidant and antifungal agents which could be useful in the cosmetic, food and pharmaceutical industries.
Key words: Pink Plumeria rubra, chemical components, cytotoxicity,
antibacterial, antifungal, antioxidant