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The research aims to study phospholipids (PL) classes and molecular species of large yellow croaker ( Pseudosciaena crocea ) roe. Both gas chromatographymass spectroscopy (GC-MS) and high-performance liquid chromatography with evaporative light-scattering detection (HPLC-ELSD) were utilized to analyze and identify the PLs fatty acids compositions and classes in the P. crocea roe, respectively. Docosahexaenoic acid (DHA, C22:6) and eicosapentaenoic acid (EPA, C20:5) account for 35.0% and 6.9% of the PLs. Phosphatidylcholines (PC), lysophosphatidylcholines (LPC), phosphatidylethanolamines (PE) and phosphatidylinositols (PI) account for 76.36 ± 0.62%, 12.30 ± 0.55%, 9.12 ± 0.02% and 1.09 ± 0.01% of the total PLs, respectively. In addition, the PLs molecular species were characterized by ultra-high performance liquid chromatography-electrospray ionization-quadruple-time of flight-mass spectrometry (UPLC-Q-TOF-MS). A total of 92 PLs molecular species was identified, including 49 PCs, 13 PEs, 10 phosphatidic acids (PAs), 13 phosphatidylserines (PSs), 3 phosphatidylglycerols (PGs), 2 sphingomyelins (SMs), and 2 PIs of the P . crocea roe. [ABSTRACT FROM AUTHOR]

[Display omitted] • P. chrysogenum used in pure-culture and enhanced fermentation of Pu-erh tea. • 69 compounds in enhanced fermentation were significantly lower. • 40 compounds in enhanced fermentation were significantly higher. • Inoculation with P. chrysogenum changed the composition of the fungal community. • Inoculation with P. chrysogenum improved the sensory quality of Pu-erh tea. Developing an effective method to improve the quality of Pu-erh tea is of great scientific and commercial interest. In this work, Penicillium chrysogenum P1 isolated from Pu-erh tea was inoculated in sterilized or unsterilized sun-dreid green tea leaves to develop pure-culture fermentation (PF) and enhanced fermentation (EF) of Pu-erh tea. Spectrophotometry and high performance liquid chromatography determined that contents of free amino acids (FAA), total tea polyphenols and eight polyphenolic compounds in PF were significantly lower than these in non-inoculation control test (CK) (P < 0.05), whereas the contents of soluble sugars and theabrownins (TB) in PF were significantly higher (P < 0.05) than in CK. A total of 416 volatile compounds were detected by headspace solid-phase micro-extraction combined with gas chromatography-mass spectrometry. Comparison to CK, 124 compounds in PF were degraded or decreased significantly [Variable importance in projection [(VIP) > 1.0, P < 0.05, fold change (FC) < 0.5], whereas 110 compounds in PF were formed or increased significantly (VIP > 1.0, P < 0.05, FC > 2). Compared with normal fermentation (NF), the levels of gallic acid, (+)-catechin, (−)-epicatechin and 64 volatile compounds in EF were significantly lower (VIP > 1.0, P < 0.05, FC < 0.5), whereas the levels of FAA and 39 volatile compounds were significantly higher (VIP > 1.0, P < 0.05, FC > 2). Amplicon sequencing of fungal internal transcribed spacer 1 (ITS1) revealed that P. chrysogenum P1 didn't become the dominant fungus in EF; while the fungal communities in EF were different from those in NF, in that the relative abundances of Blastobotrys bambusae and P. chrysogenum in EF were higher, and the relative abundances of Aspergillus niger and Kluyveromyces marxianus in EF were lower. Overall, inoculation of P. chrysogenum in unsterilized sun-dreid green tea leaves changed the the fungal communities in fermentation of Pu-erh tea, and chemical compounds in fermented tea leaves, i.e., the levels of TB and the compounds responsible for the stale flavor, e.g., 2-amino-4-methoxybenzothiazole were increased, resulting in improvement of the sensory quality, including mellower taste and stronger stale flavor. [ABSTRACT FROM AUTHOR]