@article {1107, title = {Condensed Tannins Content and their Influence on the Antioxidant Activity of Bark Hydroethanol Extract of Piliostigma reticulatum (Dc) Hochst and its Fractions}, journal = {Pharmacognosy Journal}, volume = {12}, year = {2020}, month = {March 2020}, pages = {361-368}, type = {Research Article}, chapter = {361}, abstract = {

Background: Consumption of natural products from plants is implicated in the reduction of the occurrence of diseases related to oxidative stress. Piliostigma reticulatum is a plant well known to traditional practitioners in Senegal where leaves and bark are often used against many diseases, such as ulcers, boils, syphilitic cancer, toothache, gingivitis and diarrhea. Aim: This study compared hydroethanol extract from the plant bark and its fractions by assessing their total phenol contents, antioxidant activity and the influence of condensed tannins on their activity. Method: barks were extracted by a moderate decoction with ethanol-water followed by a silica column fractionation with successively ethyl acetate, methanol and water. For this study, assays were carried out before and after precipitation of tannins by BSA and PVPP tests. Total phenol and condensed tannins of hydroethanolic extract and its fractions were performed by Folin Ciocalteu and hydrolysis methods. Antioxidant activity was evaluated by DPPH and CUPRAC tests. Results: Tannins precipitation leads a light decrease of total phenol and condensed tannins contents of samples. Total phenol content of hydroethanolic extract was 51.2 mg GAE/g vs 3.2 after BSA test and 1.7 after PVPP test whereas condensed tannins content obtained 72.2\% vs 4.2\% and 2.3\% after precipitation. Antiradical activity was lost following the elimination of tannins with IC50: 5.33 {\textpm} 0.04 mg/l vs 78.86 {\textpm} 0.92 after BSA and \> 500 after PVPP. Conclusion: This results showed the condensed tannins would be in charge of antiradical and reducing activities of plant barks and PVPP precipitated much better the tannins from those extracts than BSA.

}, keywords = {Antioxidant, Bark, Piliostigma reticulatum, Precipitation, Tannins}, doi = {10.5530/pj.2020.12.57}, author = {Serigne Ibra Mback{\'e} DIENG and C{\'e}line Mathieu and Abdou SARR and Kady Diatta-Badji and Alioune Dior FALL} } @article {1039, title = {Phytochemical Screening and Antioxidant Effect of Ethanol Leaf and Trunk Bark Extracts of Cordyla pinnata (Lepr. Ex A. Rich.) Milne-Redh. (Caesalpiniaceae)}, journal = {Pharmacognosy Journal}, volume = {11}, year = {2019}, month = {November 2019}, pages = {1415-1418}, type = {Original Article}, chapter = {1415}, abstract = {

Introduction: The aim of this study was to investigate the phytochemical composition and the antioxidant effect of ethanol leaf and trunk bark extracts of an African wild plant, Cordyla pinnata (Lepr. Ex A. Rich.) Milne-Redh. C. pinnata is used in Senegalese folk medicine to treat asthenia, spasm and various infections. Methods: The phytochemical investigation of the extracts was done using physico-chemical reactions while antioxidant effect was assessed by DPPH and FRAP assays. Results: Tannins, flavonoids, cardiotonic heterosides and triterpenoids were present in leaf and trunk bark extracts of C. pinnata. Meanwhile, anthracenic derivatives were detected in the leaf extract of C. pinnata. In DPPH assay, IC50 values of the leaf, trunk bark extracts and ascorbic acid were respectively 21.07 {\textpm} 0.11 μg/ml, 19.53 {\textpm} 0.42 μg/ml and 0.33 {\textpm} 0.11 μg/ml. In FRAP assay, the leaf and trunk bark extracts and ascorbic acid reduced significantly ferric ion. Ascorbic acid was seen to be more active in FRAP assay than the leaf and trunk bark extracts of C. pinnata. Conclusion: Ethanol leaf and trunk bark extracts of C. pinnata had revealed antioxidant activity.

}, keywords = {Antioxidant, Cordyla pinnata, Leaf, Phytochemical screening, Trunk bark}, doi = {10.5530/pj.2019.11.219}, author = {Alioune Dior FALL and Serigne Ibra Mback{\'e} DIENG and Abdou SARR and Mbaye DIENG} }