| Make water to strongly alkaline electrolysis water whose pH is11.00to12.00using the combination electrolytic cell. Removed sediment by filter, the stronglyalkaline electrolysis water whose pH is11.50is clear, no matter environmenttemperature is high or low, It can be stored over one month and more stably, and keepits pH without any changes. The cocoon unglued test indicate that the sericin onsurface of silk fibroin fibers can be removed completely by boiling for20min in thestrongly alkaline electrolysis water whose pH is11.50and liquor ratio is1:40~80(W/V), if the alkaline of electrolysis water is too low for example pH <11.00thesericin can not be removed completely, if the alkaline of electrolysis water is too highfor example pH>12.00though the sericin can be removed completely, the silk fibroinfiber will be damaged more or less.After the cocoons is in pH11.50strong alkaline electrolyzed water,70°Cvibrated and soakaged for10min in strongly alkaline electrolysis water whose pH is11.50and temperature is70°C, the cocoon silk layer will be swelled properly. Thentransferred to the same temperature or slightly lower temperature electrolytic water,reeling can be carried out. This low temperature reeling method is almost as efficientas the traditional method; some performance is even superior to the traditionalmethod.Electron microscopy results show that there are no significant differences in thesurface morphology of six kinds of silk fibroin fiber reeled by two kinds of silkreeling methods obtained by three degumming method treated proficiency. the sericinon surface of silk fibroin fibers can be removed completely by scouring20min inthe strongly alkaline electrolysis water whose pH is11.50, the impact on the silkfibroin fiber properties is the same or nearly the same as the one boiling scouring in mild soapy solution and is superior to the one boiling scouring in carbonate sodiumsolution; compared with the mild soapy solution, decomposition temperature can bedecreased1to3°C in strongly alkaline electrolysis water refining raw silk. butdecomposition temperature can be decreased4to5°C in0.2%carbonate sodiumsolution.Silk fibroin fiber tensile service test results show that there is no significanteffect on the silk fibroin fiber by traditional silk reeling and strong alkaline waterelectrolysis silk reeling, but raw silk scouring (degumming) have a more obviousimpact on the tensile properties of the silk fibroin fiber, the tensile properties of thesilk fibroin fiber is best obtained from mild soapy solution, obtained from stronglyalkaline electrolysis water is the same or nearly the same as obtained from mild soapysolution, while the tensile properties of the silk fibroin fiber obtained from carbonatesodium scouring is the worst. There is no significant effect on fiber tensile propertiesscouring for10to40min in strong alkaline electrolyzed water, if the alkaline ofelectrolysis water is too low the sericin can not be removed completely, if the alkalineof electrolysis water is too high, such as pH is12.00, long boiling scouring can causea small amount of silk peptide chain rupture, resulting the tensile properties of silkfibroin decline.Cocoon shell degumming solution can be obtained by boiling degumming usingstrong alkaline electrolysis water, after alcohol precipitation treatment, non-proteiningredients and sericin can be separated completely, and the compose of obtainedalcohol-soluble material is almostly flavonoids, and then through large holeresin resinadsorption obtained the alcohol eluate, after the second semi-preparative HPLC-DADreversed-phase chromatography separation and purification, nine kinds of monomersare obtained from the alcohol-water phase. according to LC-MS, UV spectral analysisand reference literature, the results showed that seven kinds of monomers belong tothe flavonol glucoside, five of them can emit a yellow-green fluorescence of533nmwave length by360nm UV excitation; In these seven kinds of flavonol glucoside,two of them are quercetin three-glucosidase and one of this two can emit luorescence;two of them are quercetin diglucoside and one of this two can emit luorescence; two of them are Pu acid-quercetin diglucoside and this two can emit luorescence both; thelast one is kaempferol diglucoside and it can emit luorescence also. While the othertwo kinds of caffeic acid glycoside are found in the cocoon layer first, one isglycoside caffeic acid, grape, the other is coffee diethyl glucosidase and both of themcan not emit fluorescence.The in vitro activity analse shows that the cocoon layer of non-proteiningredients that is alcohol-soluble material, its macroporous resin water phase andalcohol-water phase and nine monomers separated from alcohol-water phase are allable to scavenge DPPH free-radical. Caffeoyl glucoside is the best to scavenge DPPHfree-radical, which is2to2.5times of the other seven flavonol glucoside glucosidaseactivity; the quercetin glycoside that can emit yellow-green fluorescence can inhibittyrosinase activity; the two pu acid-quercetin diglucoside and quercetin glucosidethat can emit fluorescence can inhibit in vitro α-glucosidase activity more or less.In this paper, the experimental results shows that the strongly alkalineelectrolysis water whose pH is11.50is not only a green, environmental protection andpollution-free cocoon degumming solvent, a soup bath suit for the low temperaturereeling, but also a proficiency solvent suit for the raw silk degummingagent. Usingthe strongly alkaline electrolysis water for cocoon degumming, silk scouring, or thereeling soup bath can let the cocoon layer completely unglued, and have no significanteffect on the silk fibroin fiber, besides, this method can make sericin recoveredcompletely, as well as the operation is simple and is environmental friendly. Thisstrongly alkaline electrolysis water is valuable for silk industrialized green processing,the use and development of materials for medical utilization, the continuabledevelopment of silk industry and has a hopeful development prospects. |
PDF Full Text Request