Study on Antibacterial Effects of Extracts from Pinus massoniana Lamb. Needles

[Objectives] To study the antibacterial effects of extracts from Pinus massoniana Lamb. needles. [Methods] In this experiment, the components from Pinus massoniana Lamb. needles were extracted by systematic solvent extraction method, and the antibacterial activity against four common bacteria, Escherichia coli, Staphylococcus aureus, Bacillus subtilis, Aspergillus flavus and the antibacterial active component were examined for by punch method. [Results] Different solvent extraction rate was different, the rates of petroleum ether, chloroform, ethyl acetate, n-butanol, water extracts were 4.2%, 16.7%, 17.4%, 21.1%, 40.6%. All extracts showed inhibitory effect against test bacteria. It was observed that the inhibition of G+ was stronger than G-, and the extracts had the best antibacterial activity to Staphylococcus aureus while the weakest to Aspergillus flavus. The antibacterial activity of the components decreased in the order: ethyl acetate extract > n-butanol extract > chloroform extract > petroleum ether extract > aqueous phase. The extracts were stable under ultraviolet radiation (UV) light and long term storage. The antibacterial activity of the extracts was weaker with the increase of pH value when the pH value ≤ 8. [Conclusions] It is inferred that the antibacterial components in the extract of Pinus massoniana needles are widely distributed, and the components with medium polarity or above are the main antibacterial components.