壳聚糖双胍盐酸盐涂膜保鲜龙眼及其抑菌活性的研究

doi:10.13386/j.issn1002-0306.2012.18.085

壳聚糖双胍盐酸盐涂膜保鲜龙眼及其抑菌活性的研究

Study on chitosan diguanidinylated coating preservation of longan and its antifungal activities

摘要

摘要: 以龙眼为试材,对比壳聚糖(CTS)与其衍生物壳聚糖双胍盐酸盐(CSG)对龙眼在常温下的涂膜保鲜效果及两者对龙眼焦腐病菌和龙眼炭疽菌生长的抑制作用。将龙眼分别浸泡于质量分数为1.0%的CTS与0.2%、0.5%、1.0%的CSG溶液中,取出晾干,分装于聚乙烯篮中,于(28±2)℃的室内存放5d。测定果实的细胞膜渗透率、丙二醛(MDA)、失重率、VC、可溶性固形物(TSS)、可滴定酸(TA)含量的变化和烂果率。结果表明,用质量分数为1.0%CSG处理后的龙眼的各项生理指标均优于其他各组,说明1.0%CSG的保鲜效果优于其他几种涂膜处理。当CSG浓度为4.0mg/mL时,可完全抑制龙眼焦腐病菌菌丝的生长,当浓度大于1.0mg/mL时对龙眼炭疽菌菌丝的生长有明显的抑制作用。

Abstract: The objective of this study was to contrast the effect of chitosan diguanidinylated (CSG) which derived from chitosan coating on Dimocarpus longan Lour.with chitosan (CTS) .Effect of CSG coating in extending shelf life of longan fruits, maintaining their quality and the antifungal activity of Lasiodiplodia theobromae and Colletotrichum gloeosporioides Penz.were investigated.The longan were dipped in aqueous solutions of 1% chitosan, 0.2%, 0.5%, and 1% CSG, respectively, and followed by draining, and packaged in commercial perforated plastic baskets and stored at (28±2) ℃ for 5d.Changes in ion leakage, malonaldehyde (MDA) , mass loss, ascorbic acid, total soluble solids (TSS) , titratable acid (TA) , and decay rate were measured.The result showed that coating with 1% CSG had a significant effect on maintaining fruit quality and decreasing fruit decay.CSG could completely inhibit the growth of Lasiodiplodia theobromae at 4mg/mL and had a good antifungal activity against Colletotrichum gloeosporioides Penz.at concentrations of more than 1mg/mL.