Antibacterial and antifungal activity of phytosterols and methyl dehydroabietate of Norway spruce bark extracts

•Waste biomass of spruce is source of biologically renewable compounds with antioxidant and antimicrobial activity.•β-sitosterol show bacteriostatic activity which is necessary to observe antimicrobial activity of methyl dehydroabietate.•The synergic effect and bacteriostatic activity of β-sitosterol have not been published yet.•The antioxidant activity of bark spruce extracts was similar to antioxidants such as α-tocopherol, caffeic acid, BHT, BHA. The current study focuses on the analysis of in vitro biological activity of extract from bark of Norway spruce (Picea Abies), which can find potential application in food and cosmetic industry and pharmacology. Milled bark was subjected to Soxhlet extraction and supercritical fluid extraction to obtain two ethanol extracts. These extracts were further used to obtain their pre-extracts to n-hexane. It was investigated whether beta-sitosterol exhibits bacteriostatic activity necessary to observe antimicrobial and antifungal activity of methyl dehydroabiatate. This synergic effect and bacteriostatic activity of beta-sitosterol have not been previously reported. The greatest inhibition zone of n-hexane pre-extracts was confirmed in bacterium Pseudomonas aeruginosa (0,9 – 1,5 cm) and yeast Alternaria alternata (0,7 – 1,6 cm). It is novel, the antioxidant, antimicrobial and antifungal activity of spruce bark extracts assessed in terms of food and cosmetic fortification.