Optimization of the Cellulase−Ultrasonic Synergistic Extraction Conditions of Polysaccharides from Lenzites betulina

Abstract

Lenzites betulina has been recognized as a rich source of chemical components, including polysaccharides, sterides and sugar alcohols. In this study, cellulase−ultrasonic synergistic extraction method was applied to extract polysaccharides from L. betulina, and the response surface methodology was used to optimize the extraction conditions. The eight basic factors affecting extraction yield were evaluated by Plackett−Burman design (PBD). Then, the four important factors significantly affecting the yield of polysaccharides from L. betulina, including enzymolysis temperature, enzymolysis time, ultrasound time and ultrasound temperature, were optimized by Box−Behnken design (BBD). Maximum extraction yield of L. betulina polysaccharides was 13.64±0.09 % at a cellulase dosage of 0.8 %, enzymolysis temperature of 60 °C, enzymolysis time of 180 min, pH of 4.5, liquid‐solid ratio of 45 ml/g, ultrasound power of 300 W, ultrasound time of 20 min and ultrasound temperature of 45 °C. Subsequently, the characteristic structure of crude polysaccharides was determined by FT‐IR. Results indicated that cellulase−ultrasonic synergistic treatment is suitable for L. betulina polysaccharides extraction, and it has good prospect for development and utilization.

Optimization of Extraction and Purification of Polysaccharides from Veronicastrum axillare, and Evaluation of Their Biological Activities

“…The conditions that balanced VAP yield and its antioxidant capacity were enzyme loading 2 %, incubation temperature 47 °C, pH 4.1, solid/liquid ratio 1 : 7.6, 2.5 h digestion time, and 2.5 h extraction time. The conditions showed significant difference from some literature, [11,18] which could come from the differences in the target species and the enzyme used.…”

“…It is well‐known that pH has profound effects on enzymatic activities. Too high or too low pHs are all detrimental [18] . Figure 1 (B) indicated that the optimal pH was around 4.…”

“…However, the antioxidant activity of the isolated VAP showed maxima at 2 % enzyme loading. It was possible that the cellulase have some hydrolytic activity on VAP, and higher enzyme loading resulted in partial hydrolysis and therefore, loss of its antioxidant activities [18] . Taking into account of VAP activity and the cost of cellulase, 2 % enzyme loading was chosen for subsequent response surface DOE optimizations.…”

Isolation, structure characteristics and antioxidant activity of two water-soluble polysaccharides from Lenzites betulina

“…Firstly, dried sample was crushed and then decolorized using 10-fold volume of ethanol (80%) at 60 ℃ for 30 min twice by ultrasonic cleaner (SB25-12DTDS, Ningbo Xinyi Ultrasonic equipment co., Ltd), and the organic layer was removed by suction filtration. The residue was extracted under the conditions of cellulase dosage of 0.8%, enzymolysis temperature of 60 °C, enzymolysis time of 180 min, pH of 4.5, liquid–solid ratio of 45 ml/g, ultrasound power of 300 W, ultrasound time of 20 min and ultrasound temperature of 45 °C, respectively [ 32 ]. Secondly, the supernatant were concentrated and then precipitated with a four-fold volume of anhydrous ethanol at 4 ℃ overnight.…”

Isolation, Structure Characteristics and Antioxidant Activity of Two Water-Soluble Polysaccharides from Lenzites betulina

“…Firstly, dried sample was crushed and then decolorized using ten-fold volume of ethanol (80 %) at 60 ℃ for 30 min twice by ultrasonic cleaner (SB25-12DTDS, Ningbo Xinyi Ultrasonic equipment co., Ltd), and the organic layer was removed by suction filtration. The residue was extracted under the conditions of cellulase dosage of 0.8 %, enzymolysis temperature of 60°C, enzymolysis time of 180 min, pH of 4.5, liquid-solid ratio of 45 ml/g, ultrasound power of 300 W, ultrasound time of 20 min and ultrasound temperature of 45°C, respectively [28]. Secondly, the supernatant were concentrated and then precipitated with a four-fold volume of anhydrous ethanol at 4 ℃ overnight.…”