Background: Lysimachia vulgaris L. (Yellow loosestrife) is a medicinal plant in the family Myrsinaceae. It has been used in the treatment of fever, ulcer, diarrhea and wounds in folk medicine. It has also analgesic, expectorant, astringent and antiinflammatory activities. Two different sources of the plant (field-grown and in vitro-grown) were used to evaluate the biological activities (antibacterial, antitumor and antioxidant) of L. vulgaris. In vitro-grown plant materials were collected from L. vulgaris plants that were previously regenerated in our laboratory. Materials and Methods: Plant materials were extracted with water, ethanol and acetone. For antibacterial test, disc diffusion method and 10 different pathogenic bacteria were used. Antioxidant activity was indicated by using DPPH method. The total phenol amount by using Folin-Ciocaltaeu method and the total flavonoid amount by using aluminum chloride (AlCl 3 ) colorimetric method were determined. Results: Generally, yellow loosestrife extracts demonstrated antibacterial activity against Gram-positive bacteria (Staphylococcus aureus, S. epidermidis and Streptococcus pyogenes). Strong antitumor activity of yellow loosestrife was observed via potato disc diffusion bioassay. Nine different phenolics were also determined and compared by using High-Performance Liquid Chromatography (HPLC). Conclusion: Future investigations should be focused on fractionation of the extracts to identify active components for biological activity.

Lysimachia vulgaris L. (yellow loosestrife) is a medicinal plant that has been used in the treatment of fever, ulcer, diarrhea and wounds in traditional medicine. A reliable in vitro culture protocol for yellow loosestrife was established. Explants (leaf lamina, stem internode and root segments) were cultured on Murashige and Skoog minimal organics (MSMO) medium supplemented with various plant growth regulator combinations. Of the tested combinations, those involving benzyladenine (BA) with either indole-3-acetic acid (IAA) or indole-3-butyric acid (IBA) were the most effective for all used explants in shoot production. Best shoot proliferation was obtained from leaf lamina explant cultured on media containing 0.5 mg/l BA and 0.1, 0.5 or 1 mg/l IBA, from stem internode explant cultured on media containing 1 mg/l BA and 0.5 mg/l IBA or 0.01 mg/l thidiazuron (TDZ) and 0.5 mg/l IAA, and from root explant cultured on media containing 0.5 mg/l BA and 0.5 mg/l IAA. Regenerated shoots were rooted on MSMO medium containing different concentrations of IAA, IBA, 2,4-dichlorophenoxyacetic acid (2,4-D) and naphthalene acetic acid (NAA). IBA was determined as the most effective auxin for rooting. Most shoots developed roots on medium with 0.5 mg/l IBA.