Study On Antibacterial Properties And Mechanism Of Pineapple Leaf Fiber

The antibacterial properties and mechanisms of pineapple leaf fibers were studied. The effect of pretreatment and degumming technological conditions on antibacterial and spinnable properties were researched. Theoretical foundation for developing functional textiles of pineapple leaf fibers had been provided.Firstly, the test methods of antibacterial activities of textiles were introduced and the agar diffusion plate method and parallel streak method were used to run qualitative tests and shake flash method to run quantify tests. The result confirmed that pineapple leaf fibers possess obvious antibacterial properities to Escherichia coli, Staphylococcus aureus and Candida albicans.Secondly, the differences of antibacterial and spinnable properties after various pretreatment methods were discussed. And the steam explosion+retting method was the best way to obtain antibacterial and spinnable pineapple leaf fibers. In the steam explosion process, the optimal steam pressure was 2 MPa and maintaining time was 3 min. In the retting process, the temperature was 37℃ and time was 5 days.Thirdly, the antibacterial properties and spinnabilities of pineapple leaf fibers after degumming with sulfuric acid and sodium hydroxide were researched. The results indicated that the anti-bacterial properties and spinnabilities of pineapple leaf fibers were considerable when pickling technological conditions were 25g L-1 H₂SO₄ solution, bath ratio 1:50, temperature 55°C and time 60 min. With these pickling conditions, the best boiling off technological conditions were 15g L-1 NaOH, 4g L-1 Na₂SO₃, 3g L-1 Na₂SiO₃, 2% JFC（mass concentration to fibers）, bath ratio 1:30, temperature 100°C and time 120 min.Finally, by means of antibacterial components of pineapple leaf fibers were removed or retained, the effects of fiber chemical components and structures on antibacterial properties were researched. The porous structures of pineapple leaf fibers slow down the rate of bacterials reproduction andgrowing. And phenols, alkaloid and triterpenes exsit in lignin were the main antibacterial components.