Optimization of Microwave-Ultrasonic Assisted Extraction of Polysaccharides from Basal Part of Bamboo Shoot by Response Surface Methodology

Bamboo shoot polysaccharide,one of the important bioactive components of bamboo shoot,exhibits various healthy functions,including antioxidant,hypoglycemic effect and so on. Using the basal part of Fujian bamboo shoot(L. oldhami Nakal)as raw materials,the technology parameters of microwave-ultrasonic assisted water extraction of polysaccharides were optimized based on single factor test and response surface analysis(RSM). The results showed that the optimum process parameters of microwave-ultrasonic assisted water extraction of polysaccharides were as follows:Solid-liquid ratio of 1:30 g/mL,95℃ water bath temperature,2.0 h water bath time,600 W ultrasonic power,300 W microwave power and 3.0 min microwave-ultrasonic time. Under these conditions,the yield of polysaccharides from the basal part of bamboo shoot was 10.05%,which was 32.06% higher than that of traditional hot water extraction method. The results showed that the content of total sugar,protein and uronic acid of the polysaccharide was 74.87%,4.05% and 1.89%,respectively. This method could significantly improve the polysaccharide yield from the basal part of bamboo shoot,which could provide some theoretical reference for the comprehensive utilization of bamboo shoot and the further development of bamboo shoot polysaccharide products.