The sweet rhizomes of Polygonatum cyrtonema are widely used as a tonic and functional food. A sensitive and rapid analytical method was developed for simultaneous identification and dynamic analysis of saccharides during steam processing in P. cyrtonema using HPLC–QTOF–MS/MS. Fructose, sorbitol, glucose, galactose, sucrose, and 1-kestose were identified, as well as a large number of oligosaccharides constituted of fructose units through β-(2→1) or β-(2→6). Polysaccharides and oligosaccharides were decomposed to monosaccharides during a steaming process, since the contents of glucose, galactose, and fructose were increased, while those of sucrose, 1-kestose, and polysaccharides were decreased. The high content of fructose was revealed to be the main determinant for increasing the level of sweetness after steaming. The samples of different repeated steaming times were shown to be well grouped and gradually shift along the PC1 (72.4%) axis by principal component analysis. The small-molecule saccharides, especially fructose, could be considered as markers for the steaming process of rhizomes of P. cyrtonema.

As an edible sclerotia-forming fungus, Poria cocos is widely used as a food supplement and as a tonic in China. High-performance liquid chromatography-quadrupole/time-of-flight mass spectrometry (HPLC-QTOF-MS/MS) was applied to identify triterpene acids in fermented mycelia of P. cocos, as well as the epidermis and inner part of natural sclerotia. A total of 19 triterpene acids were identified in fermented mycelia, whereas 31 were identified in the epidermis and 24 in the inner part. Nine triterpene acids were quantitatively determined, and the concentrations of two valuable triterpenes, dehydropachymic acid and pachymic acid, reached 1.07 mg/g and 0.61 mg/g in the fermented mycelia part, respectively, and were both significantly higher than the concentration in the two natural parts. The fermented mycelia could be a good choice for producing some target triterpene compounds and functional foods through fermentation thanks to the high concentration of some triterpene acids.

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Caterpillar fungi have numerous pharmacological and therapeutic applications in traditional medicine, due to a variety of active chemical constituents, such as cordycepin and adenosine. It is imperative to discover new resource for artificial cultivation and biometabolite production since the traditional natural species are endangered. In this study, a new strain HACM 001 was isolated and identified as Ophiocordyceps xuefengensis by rDNA-ITS sequencing. This strain showed the potential of artificial infection to caterpillar larvae leading to mummification, as well as fermentation mycelia in liquid culture and cultivation stromata in solid medium. Eight nucleosides and nucleobases, especially cordycepin and adenosine, were determined and analyzed with HPLC-DAD-Q-TOF-MS/MS technology. Cordycepin was detected in all forms of present O. xuefengensis strain at different contents, among which the highest content (37.1 μg/g) appeared in the stromata cultivated on solid medium. The content of adenosine in mycelia and stromata, respectively, reached 1155 μg/g and 1470 μg/g. Therefore, O. xuefengensis might be an alternative source for obtaining artificial fungus-caterpillar-larvae complex and producing cordycepin and adenosine.