Effect of 1-MCP on Delaying the Postharvest Senescence of Broccoli and Its Possible Physiological Mechanism
|Author||LinBiBao（Kyi Kyi Win）|
|Keywords||Broccoli 1 - MCP Storage life Quality Antioxidant enzymes SDS-PAGE Senescence|
Broccoli (Brassica oleracea, cv. Italica) rich in vitamin C and anticancer glucosinolates and valued by consumers. Broccoli bouquet of products organs has a very high intensity of respiratory vulnerable to aging at higher temperatures, 20 ℃ under its shelf-life is only about two days. In developed countries, refrigerated and controlled atmosphere immediately after harvest broccoli storage and preservation, good results in reducing the post-harvest losses of broccoli. However, this method is relatively expensive, not widely available in developing countries, so explore Broccoli storage under economically viable in the higher temperature (20 ℃) ??method has practical significance. New ethylene inhibitor 1-MCP is an efficient, safe and small environmental pollution, and thus in crop preservation has broad application prospects. Broccoli's the cultivars \physiological mechanisms of aging. The main findings are as follows: 1) 20 ° C to 0-20 μl/l1-MCP, processing broccoli 3,6,9 and 12h in all treatments to deal with the effect of broccoli flower ball six hours 2.5μl / l most good, not only so that the extended shelf life and can effectively delay bouquet of yellow flowers and weightlessness, inhibition of the nutritional content of chlorophyll, carotenoids and vitamin C degradation. Countries and regions in the cold chain is not yet widespread, broccoli products in all aspects of the selection of classification, transportation and sales in the post-harvest may be in high temperature conditions ,1-MCP treatment can replace the demand for low-temperature and still maintain a good quality, and has great practical value in the preservation of broccoli. 2) the natural aging process of the bouquet, membrane lipid peroxidation products - malondialdehyde (MDA) content will continue to rise, while 2.5μl/l1-MCP treatment inhibited the increase in MDA content. Analysis and isoenzyme electrophoresis analysis of the activity of antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT) that ,1-MCP treatment increased activity of peroxidase (POD) activity. Addition ,1-MCP can also antioxidants - vitamin C and carotenoid content higher than that of the control, and the role of antioxidant enzymes and antioxidants to delay senescence of broccoli. 3) Previous studies have generally believed that broccoli natural aging process between chlorophyll and protein degradation are closely related, we found that the link between the two is not close. Especially broccoli bouquet in storage will rise within three days of the soluble protein content, while 1-MCP treatment will promote the increase in protein content, which may be related to the generation of stress protein induction and storage conditions; 3 days after the onset of soluble protein content significantly decreased protein degradation, which may ,1-MCP treatment can inhibit the degradation of the protein curd. 10th chlorophyll content during storage friends asked declining ,1-MCP can inhibit Lee. Degradation. 4) SDS-PAGE compare 1-MCP treatment and control in broccoli aging process water-soluble and alcohol-soluble protein Lee l and content changes. The results showed that the protein changes more complicated in grief-old process, changes in the alcohol-soluble protein and soluble protein showed three kinds: first class protein throughout basic stable; second class of proteins with the bouquet of aging gradually decreased or disappeared: The third type of protein increased with the aging of the bouquet or emerging. Two types of proteins after their small change may be related to the aging of the bouquet. 1-MCP treatment can inhibit or delay the decomposition of the second protein and the emergence of the third class of protein, thereby delaying broccoli mourning old. Gliadin more generally in cereals, we found that broccoli also contain gliadin, several proteins closely associated with aging, small molecular weight of the flower ball for 2 second and 25 * D proteins in aging in the late 66 * D protein with bouquet of sorrow old gradually reduced, 1-MCP may be achieved through the regulation of these proteins the role of aging. 5) different organs of broccoli (flower ball and stem) of 1-MCP reaction ,1-MCP delay the old sorrow for Sichuan curd. 1 - ** P treatment and the emergence of the effect of the third class of proteins expressed as the rate of increase of water-soluble and alcohol-soluble protein content in curd 1-MCP treatment inhibit or delay the decomposition of the second protein than stems small bigger: more pronounced bouquet small.