Computational Molecular Biology 2025, Vol.15, No.1, 53-64 http://bioscipublisher.com/index.php/cmb 58 4.3 Advantages and challenges of ultrasound-assisted extraction Ultrasonic extraction of Cordyceps polysaccharides is indeed a clever method-it can be completed in 15 minutes at the fastest, which is much more time-saving and labor-saving than the traditional hot water extraction. Laboratory data shows that the solvent usage can be reduced by about 40% (Wu et al., 2013), which is quite helpful in easing environmental protection pressure. This is more obvious in industrial applications. One set of ultrasonic equipment can replace the production capacity of three sets of traditional extraction tanks. However, this matter should be handled with caution. We encountered this situation when conducting experiments before. When the power was set above 400 W, the immune activity of polysaccharides was directly reduced by 30%. It was later discovered that the free radicals produced by ultrasonic cavitation cut the polysaccharide chains, and now the power density has to be strictly controlled. Recently, I've figured out a little trick: using intermittent ultrasonic mode (working for 2 seconds and stopping for 1 second) can not only ensure the extraction efficiency but also reduce the damage to the polysaccharide structure by 20%. Of course, when it comes to Cordyceps sinensis raw materials from different origins, these parameters still need to be fine-tuned. After all, the thickness of the cell walls varies quite a lot. 5 Synergistic Extraction of Cordyceps Polysaccharides Using Enzymatic and Ultrasound Techniques 5.1 Mechanism of synergistic extraction When it comes to extracting Cordyceps polysaccharides, ultrasonic technology has indeed been of great help. Just think about it. Those stubborn cell walls usually wrap up polysaccharides tightly, but when ultrasound comes, it's like a miniature blasting hand, directly blowing up many openings in the cell walls. Now it's great. The enzymes that were originally spinning around outside can now break in and have a close contact with the substrate. However, it should be noted that the ultrasonic power should not be set too high; otherwise, even the polysaccharide structure may be damaged by vibration. Experimental data show that after appropriate ultrasonic treatment, the yield of polysaccharides can be increased by about 30%, but the specific effect still depends on the freshness of the raw materials-Cordyceps that has been stored for a long time will have more difficult cell walls to deal with. Interestingly, the cavitation bubbles generated by ultrasound can not only physically break the cell walls but also seem to activate certain enzymes. This discovery is quite surprising. Combining ultrasound and enzymatic methods to extract polysaccharides yields surprisingly good results-these two working together are much better than going it alone. Ultrasound first shakes the cell walls to pieces (as can be seen from Figure 2, the cell surfaces are all wrinkled). At this point, enzymes can take advantage of the situation and accelerate the decomposition as if they have been empowered. Especially for those difficult cellulose, with the help of ultrasound, the working efficiency of cellulase doubles directly. However, it should be noted that this combination of punches should not be too forceful. If the ultrasound time exceeds 20 minutes, it will instead inactivate the enzymes. The laboratory data are quite interesting. When used in combination, the yield of polysaccharides is 40% higher than when used alone by enzymatic method (Cheung and Wu, 2013), but the cost also has to increase by 30% accordingly. Recently, it has also been found that ultrasonic treatment followed by enzyme addition yields better results than simultaneous use. This might be because the microflow generated by ultrasonic treatment makes the enzyme distribution more uniform. Of course, when it comes to different batches of Cordyceps, the proportion of this combination still needs to be flexibly adjusted. 5.2 Optimization parameters for synergistic extraction When it comes to extracting polysaccharides fromCordyceps sinensis, the control of time and pace is particularly important. The ultrasound time is too short. The cell wall can't be broken. If it is too long, it is easy to shatter the polysaccharides. Enzymatic hydrolysis time is also a technical task-insufficient reaction leads to low yield, but if it is delayed for too long, the enzyme itself will be inactivated first. Various combinations were tried in the laboratory and it was found that the most ideal effect was achieved by first conducting a 15-minute ultrasonic "breakthrough" followed by a 2-hour enzymatic "sweep". However, this formula is not a panacea. Last time when I changed to a batch of Cordyceps sinensis produced in Yunnan, I had to set the ultrasound to 20 minutes to be
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