Fresh-Keeping Effects And Mechanism Of Chinese Winter Jujube Using Aureofuscin Treatments

Chinese winter jujube has a broad development prospects and market value with a high therapeutic value and a variety of health benefits. But its storage period is only 3 to 5 days under room temperature and this problem has seriously hampered the development of Chinese winter jujube industry. Studies has shown that Alternaria alternata and Penicilliun expansum are the mainly pathogens of Chinese winter jujube, and mainly diseases of it include black mold disease, black spot disease and red spot disease.Chemical preservation methods are used widely in fruit preservation, but because jujube’s edible section contains the peel, the residue chemical reagent may harmful to human, so that it has an important significance to select an efficient, low-residue and natural, safe preservation antiseptic agent for the development of jujube industry.Aureofuscin is a polyene macrolide antifungal antibiotic which chemical structure and bioactive are very similar to Natamycin. Both they are belong to the natural, broad-spectrum, low toxicity antifungal bioactive substances. Currently, Natamycin mainly relies on imports, however Aureofuscin has the independent intellectual property rights and has stronger antibacterial effect of the main Chinese winter jujube’s pathogens, includes Saccharomyces, Penicillium, Rhizopus, etc., so it is speculated that Aureofuscin jujube will have better preservation effect.Aureofuscin is colorless and odorless, it has great food preservation effect and with no affecting the taste and sensory quality of food. Because it is almost insoluble in water and fat, Aureofuscin is not absorbed by the body after ingestion and excreted with the feces so that it will hopefully be developed into an efficient and natural food preservative.In this experiment, it studied the antibacterial effect of Aureofuscin on major jujube pathogens, the postharvest preservative effect, residue dynamics and acute toxicity of Aureofuscin. The results showed:1. Aureofuscin had a good inhibition with major jujube pathogens, antibacterial diameters of 100μil (0.624mg·ml-1) Aureofuscin solution on Penicilliun expansum and Alternaria alternate were respectively 3.7cm,1.95 cm;2. Compared to the control group, Aureofuscin could significantly inhibited fruit turn red, soft, weight lost and rot. It could effectively prevent VC, TSS and TA contents of jujube decreased, and inhibited the increase of MDA content, maintain the activity of PG and PAL. Under conditions of 4℃ storage, preservation effect of Aureofuscin was better.3. Use of Aureofuscin caused less residues in fruits, only 1.58mg·kg-1, and decompose rapidly after treatment jujube. Jujube remaining Aureofuscin half-life under room temperature was 3.18h, under 4℃ was 4.02 h;4. It was proved that Aureofuscin was a low toxicity substance.