川芎提取液对脐橙的防腐保鲜效果

Effect of Ligusticum chuanxiong hort extract for antisepsis and preservation of navel orange

为了开发植物源脐橙贮藏保鲜技术,该文研究了川芎提取液在离体和活体条件下对采后脐橙的主要致腐菌意大利青霉和指状青霉的抑制作用,以及对贮藏期脐橙品质和生理生化的影响。结果显示:在离体条件下,川芎提取液对2种供试菌种有显著的抑制作用(P<0.05),最低抑菌质量浓度均为25.00 mg/m L;在活体条件下,川芎提取液能有效抑制2种病原菌在脐橙上的生长,且质量分数为4%效果较好,与体积分数为50%乙醇处理的对照相比,差异显著(P<0.05);在脐橙采后贮藏中,川芎提取液对脐橙的防腐保鲜效果与其质量分数相关,其中质量分数为4%的效果较好,与蒸馏水处理的对照相比,能够显著(P<0.05)降低采后脐橙的腐烂率、失重率和丙二醛含量,延缓总酸的下降,以及诱导过氧化物酶活性上升,有利于维持可溶性固形物和总糖质量分数,而对维生素C和果皮色泽的变化无显著影响(P>0.05)。结果表明,川芎提取液用于脐橙贮藏保鲜切实可行,研究结果为脐橙天然保鲜剂的开发及脐橙在贮藏、运输和销售期间防腐保鲜提供参考。

Concerning the tissue of the decay of navel oranges caused by blue and green moulds, the continuous use of fungicides has faced 2 major problems: the increasing public concern regarding fungicidal residue contamination, and the proliferation of resistance in the pathogen populations. The aim of this research was to develop the new preservative technology of navel oranges. The bioactivity ofLigusticum chuanxiong Hort extractin vivo andvitro againstPenicillium italicumand Penicillium digitatum, and their effects on the quality of postharvest navel orange fruits were studied. The Ligusticum chuanxiong Hort’s rhizoma was extracted by 70% (v/v) ethanol under ultrasonic conditions. Then the concentration of the extract was adjusted for further experiments. In thein vitroexperiments, thechuanxiong extract was added into potato dextrose agar (medium), and a series ofchuanxiong extracts with different concentrations containing medium were developed to test the minimum inhibitory concentration (MIC) onPenicillium italicumand Penicillium digitatum. The results showed thatPenicillium italicumand Penicillium digitatumwere inhibited effectively in presence of the extract, and the MIC was both 25.00 g/mL. In thein vivo experiments, the fruits were wounded, inoculated withPenicillium italicum orPenicillium Digitatum, and treated withchuanxiong extract. After 1 week, the green and blue moulds incidences on treated oranges were both reduced. It demonstrated that the extract could significantly inhibit pathogen grow in the navel oranges when the concentration was 4%. The extract was further used on postharvest navel oranges, and the extract had no adverse impact on fruits. What was more, 3% and 4% extracts were good for fruits, especially the 4% extract. The results showed that, compared to the control group, the extract had a significant effect on the preservation and quality maintenance of postharvest navel oranges when the concentration was 4%. The decay time was put off, the fruit rotting rate, the weightlessness rate, and the malonaldehyde (MDA) content were significantly reduced; the activity of peroxidase (POD) was induced, the decrease of total acid content was delayed, and the contents of total sugar and total soluble solid were kept well to some extent, but it had little effect on the peel’s color and the content of vitamin C. After 100 d storage at room temperature, the fruit treated with 4% extract had the rotting rate of 5.42%, the weightlessness rate of 4.16%, the color value of 17.18, the total acid content of 0.51 g/(100 g), the vitamin C content of 52.40 mg/(100 g), the total soluble solid content of 13.9%, the total sugar content of 11.70 g/(100 g), the peroxidase activity of 8.3 u/(min·g), and the malonaldehyde content of 3.89μmol/g. The results indicated that, applying thechuanxiong extract on postharvest navel orange fruits was simple and feasible. This research provides a reference for the exploitation of natural fungicides, and the preservation of navel oranges with Chinese medicine during storage, transportation and selling.