An alkaloid of Norway spruce (Picea abies) possesses powerful antibacterial and antifungal potential

Abstract

Norway spruce, Picea abies, along with other species of Picea contains a number of small molecular mass alkaloids [1]. To the best of our knowledge there exists no earlier publications on the antimicrobial effects of spruce alkaloids. On the other hand, there are a number of publications on the antibacterial effects of essential oils and oil rich fractions of spruce [2]. Spruce needle oil and decoctions of young spruce are traditionally used for treatment of cold, bronchitis, symptoms of fever and stomach ailments, among others. The present study was carried out to evaluate the antimicrobial effects of alkaloid EpI found in P. abies. Focus was put on bacterial strains causing food poisonings as well as other common human pathogenic bacteria and two Candida species. The antimicrobial effects were evaluated using microplate methods. The lowest minimum inhibitory concentration of 5.37 µg/ml was recorded against Pseudomonas aeruginosa, Enterococcus faecalis, Candida glabrata and Candida albicans. For comparison, the conventionally used tetracycline gave a MIC of 15.6 µg/ml against P. aeruginosa and amphotericin B a MIC of 1.95 µg/ml against C. albicans. Very promising MIC value of 10.75 µg/ml was recorded against Staphylococcus aureus and Bacillus cereus, both common food poisoning bacteria. In addition promising MIC of 43 µg/ml was recorded against Salmonella enterica. Further studies will be performed on testing this antimicrobially promising alkaloid EpI for cytotoxicity against fibroblasts and other normal cell lines.