A targeted GC-MS/MS approach for the determination of eight sterols in microgreen and mature plant material

Comprehensive profiling and evaluation of free/conjugated Phytosterols in crops using chemical derivatization coupled with UHPLC-ESI-QTOF-MS/MS

Phytosterols are naturally existed in crops but their detection is constrained by sensitivity and accuracy due to the inefficient analytical approaches. This study hypothesizes that an untargeted analytical method combining chemical derivatization with ultrahigh performance liquid chromatography-electrospray ionization quadrupole time-of-flight mass spectrometry can identify the various composition and contents of phytosterols in different crops. The results showed that chemical derivatization significantly enhanced intensity of phytosterols compared with non-derivatized samples. Using precursor ion scanning (PIS) of m/z 252.0690, dansyl chloride-labeled phytosterols were identified, demonstrating that rapeseeds had the highest content of total phytosterol (3981.2 ± 95.3 mg/kg), followed by sunflower seeds, flaxseeds, corn and rice, respectively. Principal component analysis revealed significant variations in phytosterol distribution among 15 crop samples, suggesting the applicability of phytosterol profile as a marker for phytosterols-contained crops. Hence, the proposed analytic approach proves high efficiency and accuracy in determining phytosterols and advances the study for phytosterol-enriched crops.

Unique sterol metabolite shifts in inflammatory bowel disease and primary sclerosing cholangitis

Inflammatory bowel disease (IBD) triggers chronic intestinal inflammation and is linked to primary sclerosing cholangitis (PSC). Cholesterol homeostasis, tightly regulated under normal conditions, becomes disrupted in both inflammation and chronic liver disease. We analyzed fecal and serum levels of cholesterol synthesis precursors, oxysterols, and phytosterols in 87 patients with IBD (81 for serum analysis) including patients with Crohn's disease (CD) and ulcerative colitis (UC), 11 patients with PSC, 21 patients with PSC-IBD (18 for serum analysis), and 16 healthy controls (17 for serum analysis). Cholesterol was analysed by flow injection analysis on a high-resolution hybrid quadrupole-Orbitrap mass spectrometer and further serum sterols and all fecal sterols were analysed by a gas chromatograph mass spectrometer. Serum levels of lanosterol, 7-dehydrocholesterol, 7-beta-hydroxycholesterol, 27-hydroxycholesterol, and the plant sterols campesterol, stigmasterol, and sitosterol were similar across control and patient groups. Notably, serum lathosterol was elevated in CD patients compared to those with UC, PSC, PSC-IBD, and healthy controls. All other serum and fecal sterols showed no differences between CD and UC. Cholesterol synthesis precursors in serum, serum cholesterol levels, and both serum and fecal plant sterol levels decreased with increasing IBD severity. Consequently, serum cholesterol, campesterol, sitosterol, and fecal 5-beta sitostanol and 5-alpha sitostanol were negatively correlated with C-reactive protein and fecal calprotectin. The conversion of cholesterol to coprostanol in feces was impaired in IBD, PSC, and PSC-IBD, independent of bowel inflammation severity or liver disease extent. Patients with PSC, and to a lesser extent PSC-IBD, had elevated serum plant sterol levels, positively correlating with liver disease markers. In conclusion, in patients with IBD, cholesterol biosynthetic precursors, serum cholesterol levels, and fecal plant sterols decrease with intestinal inflammation. An inverse association of serum plant sterols with intestinal inflammation was observed in patients with IBD and a direct association of serum phytosterols with liver injury in patients with PSC. The conversion of fecal cholesterol to coprostanol was impaired in all patient cohorts. IBD and PSC alter serum sterol levels differently, whereas changes in fecal sterols are not disease specific and are moderate.

Exploration of the Lipid Profile of Edible Oleaginous Microgreens by Mass Spectrometry-Based Lipidomics

The spreading awareness of the health benefits associated with the consumption of plant-based foods is fueling the market of innovative vegetable products, including microgreens, recognized as a promising source of bioactive compounds. To evaluate the potential of oleaginous plant microgreens as a source of bioactive fatty acids, gas chromatography-mass spectrometry was exploited to characterize the total fatty acid content of five microgreens, namely, chia, flax, soy, sunflower, and rapeseed (canola). Chia and flax microgreens appeared as interesting sources of α-linolenic acid (ALA), with total concentrations of 2.6 and 2.9 g/100 g of dried weight (DW), respectively. Based on these amounts, approximately 15% of the ALA daily intake recommended by the European Food Safety Authority can be provided by 100 g of the corresponding fresh products. Flow injection analysis with high-resolution Fourier transform single and tandem mass spectrometry enabled a semi-quantitative profiling of triacylglycerols (TGs) and sterol esters (SEs) in the examined microgreen crops, confirming their role as additional sources of fatty acids like ALA and linoleic acid (LA), along with glycerophospholipids. The highest amounts of TGs and SEs were observed in rapeseed and sunflower microgreens (ca. 50 and 4-5 μmol/g of DW, respectively), followed by flax (ca. 20 and 3 μmol/g DW). TG 54:9, 54:8, and 54:7 prevailed in the case of flax and chia, whereas TG 54:3, 54:4, and 54:5 were the most abundant TGs in the case of rapeseed. β-Sitosteryl linoleate and linolenate were generally prevailing in the SE profiles, although campesteryl oleate, linoleate, and linolenate exhibited a comparable amount in the case of rapeseed microgreens.