Abstract:

The aqueous extract and ethanolic extract of pine needles and their mixture at the ratio of 1:1 were compared in  antimicrobial activity, and the antimicrobial activity comparison among aqueous extract and ethanolic extract of old pine needles and those of young pine needles were conducted. Meanwhile the effects of pH value on the antimicrobial activities of aqueous extract of young pine needles against 4 species of bacteria were investigated. The results indicated that the aqueous extracts display significantly higher activity than the ethanolic extracts while the extracts of young pine needles demonstrate higher activities than those of old pine needles. Under acidic condition, the aqueous extract of young pine needles has better antibacterial effects, and can significantly inhibit the growth of the most common species of spoilage bacteria except fungi and yeast. These antimicrobial effects are obviously stronger than those of common food preservatives.

Key words: pine needles, extract, antimicrobial activity