Medicinal plants have been used for the treatment of various diseases and still play an important role in covering the basic health needs in the developing countries like Ethiopia. In this study, successive extraction, partial purification using column chromatograpy, phytochemical screening, determination of the total phenolic and flavonoid content, and the antioxidant and antibacterial activities of the petroleum ether, chloroform, and ethanol stem bark extracts and fractions of Clematis simensis are reported. The results show the presence of different valuable phytochemicals. The total phenolic content is 54.744, 68.933, and 87.522 mg g^–1 of gallic acid equivalent for the petroleum ether, chloroform, and ethanol extracts, respectively. The total flavonoid content of the petroleum ether, chloroform, and ethanol extracts are 22.770, 37.223, and 52.289 mgCE g^–1, respectively. This could lead to potential biological activity of the plant extract. Besides, the ethanol extract exhibits higher antioxidant activity than all the tested extracts. Likewise, the extracts have promising antibacterial activity with that of the ethanol extract being higher than those of the chloroform and petroleum extracts as well as isolated fractions.

Nowadays water hyacinth coverage in Lake Tana is increasing day to day. Recently, considerable attention has been given to this plant to utilize and use as economical sources in many parts of the world. However, utilization of this plant is limited in Ethiopia. According to different findings, the tannin and other phytochemical contents of the water hyacinth vary from place to place where the plant grows up. Therefore, the aim of this study was to determine the tannin and other phytochemical constituents of the plant, in the case of Lake Tana, Ethiopia. The leaves and stem parts of the plant were extracted using distilled water, acetone, and ethanol solvents. The phytochemical, FTIR, and tannin content of the extracts were carried out following standard procedures. The phytochemical analysis revealed the existence of primary and secondary metabolites such as alkaloids, flavonoids, phenols, tannins, starch, and protein in the leaves and stems parts of the plant. The tannin content of water hyacinth leaves has higher tannin content as compared to that of the stem. During tannin content determination the total ash in % and pH value of leaf and stem tannins were determined. The pH of the leaf part was higher; however, the total ash content was lower than that of the stem. The FTIR spectrum data of the leaves and stems of the plant was recorded in the wavenumber range of 4000 and 500 cm ⁻¹ . This revealed the presence of different functional groups in both leaf and stem parts of the plant. The phytochemicals found in the plant parts, including primary and secondary metabolites, could be used for medicinal and pharmaceutical applications as well as for textile and tanning industry wastewater treatment. Similarly, according to the findings of this study, water hyacinth leaves and stem parts have a tannin which will be used as an ideal agent for the tanning and retanning process in leather processing.