Study On The Preparation And Properties Of Chitosan-Berberine Composite Membrane

Chitosan as an edible packing material has been extensively researched. Many studies about chitosan applied to storage of fruits and vegetables have been reported. However, the film prepared with chitosan as sole ingredient is always rigid and brittle in nature, which exerts a negative effect on mechanical properties and storage. This study focused on the mechanical properties and antimicrobial activity of chitosan-berberine composite film added with non-toxic edible industrial plasticizers, including triethyl citrate(TEC), triethyl 2-acetyl citrate (ATEC), tributyl citrate (TBC) and acetyl tributyl citrate (ATBC). The optimal blends were selected by orthogonal test. As a consequence, the mechanical properties of edible film were improved after adding TBC, and the most optimal film solutions were prepared with chitosan 2%(w/v), glycerin 1.25%(w/v) and plasticizer 1.5%(v/v) at 60℃. And the optical composite membrane strength is 14.594 MPa, elongation at break is 72.631%. The compatibility of the blends has been verified by infrared spectrum. Some small holes were found to evenly distribute in membrane when observation with scanning electron microscope(SEM), indicating its good permeability.Berberine, a common vision of isoquinoline alkaloid, it has broad-spectrum antimicrobial effect. Previous study has found that berberine has the completely inhibition effect on Monilinia fructicola. Based on these results, the inhibition of this membrane on Monilinia fructicola and E. coli were investigated by inhibitory zone methods, no obvious differences were observed in antimicrobial activity with or without plasticizer. The inhibition of this membrane on E. coli was also checked by turbidimetry, it was found that the blend with TBC had antimicrobial activity on E. coli; the rate of weight loss and the infected index of peaches were also investigated to evaluate the composite membrane package processing. Compared with the control, the rate of weight loss and the infected index was lower for edible films. After treatment of 10 days, the infected index of peaches was up to 30%, and weightlessness rate up to 60%. By contrast, weightlessness rate of the control group reached 40%, decay index nearly 90%. Taken together, this composite membrane can prolong storage time of peach.Finally, drug release experiment indicated that this composite membrane showed release of berberine.