Chemical Profile, Antioxidant and Anti-Inflammatory Potency of Extracts of Vitex madiensis Oliv. and Crossopteryx febrifuga (Afzel ex G. Don).

Vitex madiensis Oliv. (Lamiaceae) and Crossopteryx febrifuga (Rubiaceae), two plants commonly used in traditional African medicines to treat malaria and pain, were studied either to determine their chemical profiles or to evaluate their antioxidant and anti-inflammatory activities. In this study, we investigated leaves, trunk bark, root bark and fruits methanolic extracts of both plants in order to find out which part of the plant is responsible for the activity. The analyses of the chemical profiles allowed us to confirm the presence of several ecdysteroids, especially 20-hydroxyecdysone in some parts of V. madiensis and to highlight the presence of organic acids and phenol derivatives in C. febrifuga. Among the four parts of the plants studied, only the fruits extract of C. febrifuga could present anti-inflammatory activity by decreasing ROS production. The leaves and trunk bark extracts of V. madiensis showed significant free radical scavenging activity compared to ascorbic acid, and the same extracts decrease ROS production significantly. The activity of these two extracts could be explained by the presence of ecdysteroids and flavonoids. The ROS production inhibition of V. madiensis is particularly interesting to investigate with further analyses.

Optimization of the extraction of the p-menthadienol isomers and aristolone contained in the essential oil from Elyonurus hensii using a 23 full factorial design.

The aim of this study was to optimize the extraction of p-menthadienol isomers and aristolone from the essential oil of Elyonurus hensii by hydrodistillation. The study of the seasonal variation in the chemical composition has shown that the plant material has been subject to a natural selection regarding the biosynthesis of the p-menthadienol isomers: during periods of water stress, the extracts are rich in cis and trans-p-mentha-1(7),8-dien-2-ol and poor in cis and trans-p-mentha-2,8-dien-1-ol. Regarding the modeling, eight experiments were carried out by considering three easily interpretable factors (the extraction duration, the residual water content and the state of the division of the plant material). The average yield was 1.33% for the aerial part and 0.74% for the roots. The residual water content is the most important factor, which significantly influences the average yield of the essential oil and the content of the major constituents. Regarding the aerial part, a low residual water content of the plant material varies the essential oil yield (from 0.40% to 2.11%) and the content of cis and trans-p-mentha-2.8-dien-1-ol (from 15.87% to 23.24%). At the root level, the samples that have a very low residual water content provide extracts richer in aristolone. The combined effects of the extraction duration, the state of division, and the residual water content influence greatly the extraction of aristolone (from 36.68% to 54.55%). However, these interactions are more complex and difficult to assess.