Ethobotanical survey of Rinorea dentata (Violaceae) used in South-Western Nigerian ethnomedicine and detection of cyclotides
No Thumbnail Available
Date
2016
Journal Title
Journal ISSN
Volume Title
Publisher
Elsevier Ireland Ltd
Abstract
Ethnopharmacological relevance: People living in the tropical rain forest of South-Western Nigeria use
Rinorea dentata (P. Beauv.) Kuntze (Violaceae) in ethno-veterinary medicine to facilitate parturition.
There are no evidence-based pharmacological investigations for the uterotonic activity of this plant.
Aims of study: (i) Collection of data about the ethnopharmacological uses of R. dentata and evaluation of
its uses and applications in health care; (ii) determining potential uterotonic effects in vitro, and (iii)
chemical characterization of R. dentata, which is a member of the Violaceae family known to express
circular cystine-knot peptides, called cyclotides.
Materials and methods: The ethnopharmacological use of R. dentata in settlement camps within the area
J4 of Omo forest has been investigated by semi-structured questionnaires and open interviews. Use index
analysis has been performed by seven quantitative statistical models. Respondents’ claim on the beneficial ethno-veterinary application of the plant to aid parturition has been investigated in vitro by
myometrial contractility organ bath assays. The bioactive plant extract was screened by chemical derivatization and mass spectrometry-based peptidomics using reversed-phase HPLC fractionation and
MALDI-TOF/TOF analysis.
Results: Based on the survey analysis, medicinal preparations of R. dentata have been used for antimicrobial and anti-malaria purpose in humans, and for aiding parturition in farm animals. The latter
application was mentioned by one out of six respondents who claimed to use this plant for any medicinal
purpose. The plant extract exhibited a weak uterotonic effect using organ bath studies. The plant contains
cyclotides and the peptide riden A has been identified by de novo amino acid sequencing using mass
spectrometry.
Conclusion: Few dwellers around the settlement camps of the tropical forest of Omo (Nigeria) use R.
dentata for various health problems in traditional veterinary and human medicine. The weak uterotonic
effect of the cyclotide-rich extract is in agreement with the low use value index obtained for this plant.
Cyclotides have been reported in the genus Rinorea confirming the ubiquitous expression of these stable
bioactive plant peptides within the family of Violaceae.
Description
Keywords
Rinorea dentata, ethnopharmacological