Plumeria rubra L. (Apocynaceae): Ethnobotany, Phytochemistry and Pharmacology: A Mini Review

Plumeria rubra L.- A review on its ethnopharmacological, morphological, phytochemical, pharmacological and toxicological studies

ETHNOPHARMACOLOGICAL RELEVANCE

Plumeria rubra L. (Apocynaceae) is a deciduous, commonly ornamental, tropical plant grown in home premises, parks, gardens, graveyards, because of its beautiful and attractive flowers of various colours and size. The different parts of the plant are used traditionally to treat various diseases and conditions like leprosy, inflammation, diabetic mellitus, ulcers, wounds, itching, acne, toothache, earache, tongue cleaning, pain, asthma, constipation and antifertility.

AIM OF THE REVIEW

The main aim of this review is to provide an overview and critically analyze the reported ethnomedical uses, phytochemistry, pharmacological activities and toxicological studies of P. rubra and to identify the remaining gaps and thus supply a basis for further investigations. The review also focuses towards drawing attention of people and researchers about the wide spread pharmaceutical properties of the plant for its better utilization in the coming future.

MATERIAL AND METHODS

All the relevant data and information on P. rubra was gathered using various databases such as PubMed, Springer, Taylor and Francis imprints, NCBI (National Center for Biotechnology Information), Science direct, Google scholar, Chemspider, SciFinder, research and review articles from peer-reviewed journals and unpublished data such as Phd thesis, etc. Some other 'grey literature' sources such as webpages, ethnobotanical books, chapters, wikipedia were also studied.

RESULTS

More than 110 chemical constituents have been isolated from P. rubra including iridoids, terpenoids, flavonoids and flavonoid glycosides, alkaloids, glycosides, fatty acid esters, carbohydrates, animo acids, lignan, coumarin, volatile oils, etc. The important chemical constituents responsible for pharmacological activities of the plant are fulvoplumierin, plumieride, rubrinol, lupeol, oleanolic acid, stigmasterol, taraxasteryl acetate, plumieride-p-E-coumarate, rubranonoside, rubrajalellol, plumericin, isoplumericin, etc. The plant possess a wide range of pharmacological activities present namely antibacterial, antiviral, anti-inflammatory, antipyretic, antidiabetic, hepatoprotective, anticancer, anthelmintic, antifertility and many other activities.

CONCLUSION

P. rubra is a valuable medicinal source and further study in this topic can validate the traditional and ethnobotanical use of the plant. However, many aspects of the plant have not been studied yet. The pharmacological activity of active chemical constituent isolated from the plant is proven only for a couple of activities hence, lack of bio-guided isolation strategies is observed. Further studies on bioavailability, pharmacokinetics, mechanism of action and structural activity relationship studies of isolated pure compounds will contribute more in understanding their pharmacological effects. Higher doses of plant extracts are administered to experimental animals, therefore their toxicity and side effects in humans are needed to be thoroughly studied, although no side effect or toxicity is seen or observed in experimental animals. Studies are also essential to investigate the long term in vivo toxicity and clinical efficacy of the plant.

Potential anti-diabetic isoprenoids and a long-chain δ-lactone from frangipani (Plumeria rubra)

A decoction of Plumeria rubra flowers has been used traditionally for the treatment of diabetes in China and Mexico. Chemical investigations on the bioactive constituents of these flowers led to the isolation of 30 compounds, including the four new compounds, one iridoiod (1), two triterpenoids (4, 5), and a long-chain δ-lactone (16). In addition, 26 known compounds (2, 3, 6-15, 17-30) are also reported. All of these compounds were identified on the basis of spectroscopic data interpretation and the absolute configurations of compound 4, 5, 16 were determined by Mosher's method. Compounds 1-4, 7, 8 and 16 showed moderate to significant inhibitory activities against α-glucosidase and protein tyrosine phosphatase 1B, with 4 having IC₅₀ values of 19.45 μM and 0.21 μM, respectively.

Astonishing diversity-the medicinal plant markets of Bogotá, Colombia

BACKGROUND

Despite the importance of local markets as a source of medicinal plants in Colombia, comparatively little comparative research reports on the pharmacopoeiae sold. This stands in contrast to wealth of available information for other components of plant use in Colombia and other countries. The present provides a detailed inventory of the medicinal plant markets in the Bogotá metropolitan area, hypothesizing that the species composition, and medicinal applications, would differ across markets of the city.

METHODS

From December 2014 to February 2016, semi-structured interviews were conducted with 38 plant vendors in 24 markets in Bogotá in order to elucidate more details on plant usage and provenance.

RESULTS

In this study, we encountered 409 plant species belonging to 319 genera and 122 families. These were used for a total of 19 disease categories with 318 different applications. Both species composition and uses of species did show considerable differences across the metropolitan area-much higher in fact than we expected.

CONCLUSIONS

The present study indicated a very large species and use diversity of medicinal plants in the markets of Bogotá, with profound differences even between markets in close proximity. This might be explained by the great differences in the origin of populations in Bogotá, the floristic diversity in their regions of origin, and their very distinct plant use knowledge and preferences that are transferred to the markets through customer demand. Our study clearly indicated that studies in single markets cannot give an in-depth overview on the plant supply and use in large metropolitan areas.