Study On Preserving-freshness And Health-care Of Daylily

Daylily (Hemerocallis fulva Linn.) is an important crop in China. Five varieties: Fanlonhua, Menzihua, Baihua, Xiye, Daogan were select to studied storage character under 4℃ during 18 days. And also studied the effect of different storage temperature (20℃,4℃,1℃,-1℃,-3℃), effect of different treatments (MAP and add chemicals), and effect of different water loss treatments (5%,10%,20%) on daylily during storage time.Natural products of daylily were another research area in this study. Antioxidant properties of water and ethanol extract from hot air-dried and freeze-dried daylily flowers were studied. Further we studied acute toxicity of extracts from daylily in rats and the antioxidant properties of extracts from daylily in vivo. And the effects of daylily on sleep in rats were studied. The phenolic composition in daylily extracts were analysed by HPLC. In the ends useful methods of degrade colchicine content in daylily were compared. The results of experiments show that:1. In five varieties, Storage Character of Menzihua and Baihua were more acceptable than other varieties under 4℃ after 18 days storage.2. Experiment on effect of different storage temperature on quality, physiological of daylily varieties Menzihua resulted the optimal temperature was 1 ±2℃. Storage under -3℃ will effect the daylily chilling injury.3. The experiment of effect of different treatments on freshenss of daylily, showed that the most suitable treatments were :pick up fresh daylily→ dipping in chlorine dioxide (20ppm, 5min) →precooling (6℃ 12h) →vaccum extraction and exchange with N₂(O₂ content 1-3%)→ package→storage under 1 ℃4. Different water loss pre-treatments on daylily's experiments resulted to that storage characters of water loss 5% treatment similaried CK, but the water loss 5% treatment has low loss rates.5. Extracts of daylily flower buds from different extract and dry methods exhibited strong antioxidant activity. Their antioxidant properties were evaluated using total antioxidant activity, reducing capacity, free radical scavenging, superoxide anion radical scavenging activities and metal chelating activities, comparing with standards. Drying methods andextraction solvents showed significant effects on antioxidant activity and content of phenolic compounds in extracts from daylily flowers. In different measurements ethanol extract from freeze-dried daylily flowers showed significant higher activities.6. In acute toxicity test, no visible symptom was observed and no death occurred in rats. The medium lethal dose of daylily extracts on ICR rats was more than lO.OOg/kg (body weight), which indicated daylily extracts was actually no toxicity according the standard of toxicity grade classification.7. The experiment of antioxidant properties of daylily extract in vivo showed that daylily extract can reduce MDA content in serum and hepatic and enrich SOD content in serum and hepatic.8. Effects of daylily extract on sleep in rats experiment showed that daylily extract has hypnotics function, it can prolong the time of rat's sleep time 25 min compared the CK.9. Total phenolic content in water, ethanol and 70% methanol extracts of daylily was different, 70% methanol extract has more phenolic content. But methanol was toxicity to human, so ethanol extracts was suit for food processed.10. Total phenolic content in daylily buds and daylily flower were 197.24, 83.42ug/mL respectively. But the phenolic in daylily buds was not same in daylily flower. The daylily buds has Syringic acid and Quercetin which not in daylily flower, while daylily flower has Caffeic acid which not detected in daylily buds.11. Phenolic content in fresh daylily buds and daylily buds after one month storage was different. The fresh daylily buds has more rutin, and the main Phenolic daylily buds after one month storage was Gallic acid, (-)-Epicatechin, Ferulic acid, Quercetin.12. Heat treat, microwave treatment, NaCl dipping treatment and ultraviolet radiateon treatment can degrade colchicine very effectively. The ultraviolet radiateon treatment was more simple and can combine storeroom sanitize.