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Gideon O. Alade, Jones O. Moody, Olanrewaju R. Awotona, Saburi A. Adesanya, Daowan Lai and Peter Proksch

Abstract

Aim: To isolate the spermicidal constituents of Sacoglottis gabonensis. Materials and methods: The ethanolic extract with partitioned fractions of Sacoglottis gabonensis stem bark were subjected to sperm immobilization assay. The most active EtOAc fraction was further purifi ed by column and Semi-Preparative High Performance Liquid Chromatography to give compounds which were characterized by spectroscopic methods (UV, LC/MS, and NMR). The compound(s) was also tested for sperm immobilization activity. Results: The ethanolic extract showed 100% signifi cant (p < 0.05) sperm immobilization activity at a concentration of 30 mg/mL at 20 s compared to both negative and positive controls. The most active ethyl acetate fraction yielded methyl 3,5-dihydroxy-4-methoxybenzoate, eriodictyol and bergenin. Bergenin had 100% sperm immobilization activity at 20 mg/mL in 60 s which was signifi cant (p < 0.05) also when compared to the positive and negative control while methyl 3,5-dihydroxy- 4-methoxybenzoate, eriodictyol were not active. Conclusion: The active spermicidal constituent in Sacoglottis gabonensis stem bark extract is bergenin. However, methyl 3,5-dihydroxy-4-methoxybenzoate and eriodictyol showed no activity. This plant is known for its aphrodisiac action; hence, caution may have to be exercised in its use because of its spermicidal eff ect.

Open access

Gideon O. Alade, Jones O. Moody, Olanrewaju R. Awotona, Daowan Lai, Saburi A. Adesanya and Peter Proksch

Summary

Introduction: Similar bioactive metabolites are obtainable from host plants as well as the endophytic fungi residing in them. Objective: The aim of the study is to isolate the major compound(s) from the endophytic fungus residing in Nypa fruticans Wurmb, Arecaceae family. Methods: Purification of the ethyl acetate extract of the isolated endophytic fungus was performed by employing different chromatographic techniques and structural elucidation of the isolated compound was carried out using UV and NMR spectroscopic methods. Results: Cichorin A was isolated from the ethyl acetate extract of the solid rice cultures of Pestalotiopsis sp., isolated from N. fruticans, collected in Nigeria. Conclusions: This compound is being isolated for the first time from a fungus; it is commonly isolated from the plant Cichorium intybus L. (Compositae).

Open access

Peter M. Eze, Dominic O. Abonyi, Chika C. Abba, Peter Proksch, Festus B. C. Okoye and Charles O. Esimone

Abstract

Fungi remain a promising source of novel biologically active compounds with potentials in drug discovery and development. This study was aimed at investigating the secondary metabolites from endophytic Fusarium equiseti and Epicoccum sorghinum associated with leaves of Carica papaya collected from Agulu, Anambra State, Nigeria. Isolation of the endophytic fungi, taxonomic identification, fermentation, extraction and isolation of fungal secondary metabolites were carried out using standard procedures. Chromatographic separation and spectroscopic analyses of the fungal secondary metabolites yielded three toxigenic compounds - equisetin and its epimer 5’- epiequisetin from F. equiseti, and tenuazonic acid from E. sorghinum. These compounds are known to possess several beneficial biological properties that can be explored for pharmaceutical, agricultural or industrial purposes.