Green extraction and purification of chondroitin sulfate from jumbo squid cartilage by a novel procedure combined with enzyme, ultrasound and hollow fiber dialysis.

Chondroitin sulfate (ChS) from marine sources is gaining attention. The purpose of this study was to extract ChS from jumbo squid cartilage (Dosidicus gigas) using ultrasound-assisted enzymatic extraction (UAEE). An ultrasound with protease assistance, including either alcalase, papain or Protin NY100 was used to extract ChS. The results showed that alcalase had the best extraction efficiency. The response surface methodology was employed to evaluate the relationship between extraction conditions and extraction yield of ChS. The ridge max analysis revealed a maximum extraction yield of 11.9 mg ml- 1 with an extraction temperature of 59.40 °C, an extraction time of 24.01 min, a pH of 8.25, and an alcalase concentration of 3.60%. Compared to ethanol precipitation, purification using a hollow fiber dialyzer (HFD) had a higher extraction yield of 62.72% and purity of 85.96%. The structure characteristics of ChS were identified using FTIR, 1 H-NMR, and 13 C-NMR to confirm that the purified ChS structure was present in the form of chondroitin-4-sulfate and chondroitin-6-sulfate. The results of this study provide a green and efficient process for extraction and purification of ChS and are essential for the use of ChS for the development and production of nutrient food products or pharmaceuticals. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-023-05701-7.

Effect of revulsive cultivation on the yield and quality of newly formed sclerotia in medicinal Wolfiporia cocos.

Wolfiporia cocos is a well-known medicinal mushroom widely used in China, Japan and other Asiatic countries for its various therapeutic effects. 'Revulsive cultivation' is a newly developed method for promoting sclerotia growth in W. cocos field cultivation in China. In this report, we have systematically examined the effects of 'revulsive cultivation' on the yield and quality of newly formed sclerotia. The results showed that the genetic differences between the cultivated strain and the revulsive strain of T1 used in this study did not affect the formation process of new, large sclerotia in which the mycelia of the cultivated strain grew on pine logs directionally assembled on the revulsive strain. Additionally, 'revulsive cultivation', in which the cultivated strain and the revulsive strain used had the same or different genotypes, could remarkably increase the yield, lower the water content, and increase the water-soluble polysaccharide content of the newly formed sclerotia. Moreover, we observed that the changes in the values of the tested economic traits obtained from different genotype combinations through 'revulsive cultivation' were dissimilar. The correlations of these changes with the original sclerotium-forming ability of the cultivated strains and the genetic differences between the cultivated strain and the revulsive strain were not significant. These results will broaden our knowledge regarding the field cultivation of this medical fungus, stimulate new thinking on the study of sclerotium formation in some sclerotium-forming fungi, and promote further studies on the mechanism of sclerotium formation in W. cocos.