Chemoinformatics based comprehensive two-dimensional liquid chromatography-quadrupole time-of-flight mass spectrometry approach to chemically distinguish Chrysanthemum species

Analysis of Chemical Constituents of Chrysanthemum morifolium Extract and Its Effect on Postprandial Lipid Metabolism in Healthy Adults

Chrysanthemum extract possesses antioxidant potential and carbohydrate and fat digestive enzyme inhibitory in vitro. However, no evidence supporting chrysanthemum in modulation of postprandial lipemia and antioxidant status in humans presently exists. This study was to analyze the composition of Imperial Chrysanthemum (IC) extract and determine the effect on changes in postprandial glycemic and lipemic response and antioxidant status in adults after consumption of a high-fat (HF) meal. UHPLC-MS method was used to analyze the components of two kinds of IC extracts (IC-P/IC-E) and in vitro antioxidant activities were evaluated using 1,1-diphenyl-2-picrylhydraxyl (DPPH), 2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) and Hydroxyl radical (HR) radical scavenging assays. Following a randomized design, 37 healthy adults (age, 25.2 ± 2.6 years, and BMI, 20.9 ± 1.5 kg/m2) were assigned to two groups that consumed the HF meal, or HF meal supplemented by IC extract. Blood samples were collected at fasting state and then at 0.5, 1, 2, 4, 6 and 8 h after the meal consumption. There were 12 compounds with relative content of more than 1% of the extracts, of which amino acid and derivatives, flavonoids, carboxylic acids and derivatives were the main components. Compared with IC-E, the contents of flavonoids in IC-P increased significantly (p < 0.05), and the cynaroside content exceeded 30%. In addition, IC-P showed strong free radical scavenging activity against DPPH, ABTS and HR radicals. Furthermore, according to repeated−measures ANOVA, significant differences were observed in the maximal changes for postprandial glucose, TG, T-AOC and MDA among the two groups. Postprandial glucose has significant difference between the two groups at 1 h after meal and the level in IC group was significantly lower than that in control group. No significant differences were observed in the incremental area under the curve (iAUC) among the two groups. IC significantly improved the serum antioxidant status, as characterized by increased postprandial serum T-AOC, SOD, GSH and decreased MDA. This finding suggests that IC can be used as a natural ingredient for reducing postprandial lipemia and improving the antioxidant status after consuming a HF meal.

Fast and non-destructive discriminating the geographical origin of Hangbaiju by hyperspectral imaging combined with chemometrics

Hangbaiju is highly appreciated flower tea for its health benefits, and its quality and price are affected by geographical origin. Fast and accurate identification of the geographical origin of Hangbaiju is very significant for producers, consumers and market regulators. In this work, hyperspectral imaging combined with chemometrics, was used, for the first time, to explore and implement the geographical origin classification of Hangbaiju. The hyperspectral images in the spectral range of 410-2500 nm for 75 samples of five different origins were collected. As a versatile chemometrics tool, bagging classification tree-radial basis function (BAGCT-RBFN), compared with classification tree (CT), radial basis function network (RBFN), was applied to discriminate Hangbaiju samples from different origins. The results showed that BAGCT-RBFN based on optimal wavelengths yielded superior classification performances to CT and RBFN with full wavelengths. The recognition rates (RR) of the training and prediction sets by BAGCT-RBFN were 96.0 % and 92.0 %, respectively. Hyperspectral imaging combined with chemometric can be considered as a powerful, feasible and convenient tool for the classification of Hangbaiju samples from different origins. It promises to be a potential way for origin discriminant analysis and quality monitor in food fields.

Characterisation of catechins and their oxidised derivatives in Ceylon tea using multi-dimensional liquid chromatography and high-resolution mass spectrometry

Tea is a complex food matrix comprising of many structurally diverse compounds, of which catechins and their oxidised derivatives are of particular interest due to their nutritional functionality. However, these catechins and derivatives exist in various isomeric forms with few or no pure standards available, rendering their analysis challenging. A method combining multi-dimensional liquid chromatography (MDLC) and high-resolution mass spectrometry (HRMS) was developed for the characterisation of these compounds using Ceylon tea as a model. Based on a Plackett-Burman (PB) design, flow rate and initial methanol percentage were identified as the most significant factors (p < 0.05) affecting chromatogram coverage and resolution (Rs) for comprehensive two-dimensional LC (LCxLC) and heart-cutting two-dimensional LC (LC-LC) respectively. Central composite design (CCD) was then applied using these parameters for method optimisation and to identify second-order relationships between screened parameters. The optimised LCxLC (flow rate: 2.18 mL/min and initial methanol percentage: 28.0%) and LC-LC (flow rate: 0.86 mL/min and initial methanol percentage for different cuts: A- 10.0%; B- 15.8%; and C- 18.7%) methods were applied to the analysis of Ceylon tea samples from seven regions of Sri Lanka and demonstrated an improved separation of co-eluting isomeric compounds. Finally, with the mass spectral information from HRMS, a total of 31 compounds (eight monomers, 17 dimers, five trimers and one tetramer) were detected and putatively identified in Ceylon tea.