壳聚糖双胍盐酸盐抑菌活性及其涂膜保鲜圣女果的研究

测定了壳聚糖双胍盐酸盐(CGH)对金黄色葡萄球菌、大肠杆菌和番茄丝核菌的抑菌能力;并通过涂膜的方法处理圣女果,测定贮藏过程中果实失重率、硬度、可溶性固形物含量(TSS)、维生素C(VC)含量、细胞膜透性和总酸含量的变化。结果表明,相对于壳聚糖(CTS),CGH对金黄色葡萄球菌、大肠杆菌具有较强的抑菌能力,其最小抑菌浓度(MIC)分别为0.31mg/mL和0.62mg/mL;当CGH浓度达到2.00mg/mL时对番茄丝核菌菌丝生长抑制率可达到100%。以质量浓度为3%的CGH涂膜处理的圣女果在(28±2)℃存放12d后,失重率仅为7.5%,硬度仍有21.121N/cm2,TSS为7.2%,VC含量为21.70mg/100g FW(鲜重),膜渗透率为27.4%,可滴定酸含量为0.35%。与对照(CK)相比,显著保持了果实的品质。 

Effects of chitosan biguandine hydrochloride coating on storage quality of cherry tomato and its antimicrobial activities

The antimicrobial activities of Chitosan biguandine hydrochloride (CGH) against S. Aureus, E. Coli and Rhizoctonia solani Kuhn were studied, respectively. Cherry tomatoes mass-loss ratio, firmness, total soluble solid, VC content, film penetration ratio and soluble acid content was examined attentively after fresh-keeping process with CGH as coating film. The minimal inhibited concentrations (MIC) against S. Aureus and E.Coli were 0.31 and 0.62mg/mL, respectively. CGH at 2.00mg/mL had a total antifungal effect on Rhizoctonia solani Kuhn. CGH with concentration of 3% coated on the cherry tomatoes showed a better preservation effect after 12d storage under (28±2) ℃. The mass-loss, firmness, total soluble solid, VC content, film penetration ratio and soluble acid content were 7.5%, 21.121N/cm2, 7.2%, 21.70mg/100g FW (fresh weight) , 27.4% and 0.35%, respectively.