Amino acid fingerprinting combined with chemometric data analysis was used to differentiate milk and non-milk proteins in this study. Microwave-assisted hydrolysis and ultraperformance liquid chromatography (UPLC) were used to obtain the amino acid fingerprints. Both univariate and multivariate chemometrics methods were applied for differentiation. The confidence boundary of amino acid concentration, principal component analysis (PCA), and partial least-squares-discriminant analysis (PLS-DA) of the amino acid fingerprints demonstrated that there were significant differences between milk proteins and inexpensive non-milk protein powders from other biological sources including whey, peanut, corn, soy, fish, egg yolk, beef extract, collagen, and cattle bone. The results indicate that the amino acid compositions with the chemometric techniques could be applied for the detection of potential protein adulterants in milk.

•TAGs and DAGs in cow milk fat were firstly analysed by UPC2.•Fifty-six TAGs and DAGs were identified by Q-TOF-MS.•The present method resulted a better resolution and shorter analytical time.•The UPC2/Q-TOF-MS method could be an alternative way for TAGs and DAGs analysis.An ultra-performance convergence chromatography (UPC2) system coupled with quadrupole time-of-flight mass spectrometry (Q-TOF-MS) was successfully utilised to analyse triacylglycerols and diacylglycerols in cow milk fat. This novel approach obtained an improved resolution of triacylglycerols in comparison to previously reported chromatographic methods combined with MS detector in a shorter analytical time. A total of 49 triacylglycerols and 7 diacylglycerols were identified according to their secondary MS profiles and elementary composition. Furthermore, UPC2 is an environmental friendly analytical method with a drastic reduction of organic solvent usage. The established UPC2-MS approach has potential application in lipidomics as an alternative method besides LC–MS and GC–MS.

•Five γ-oryzanol compounds in RBO were quantified by HPLC with a single reference standard.•Seventeen batches of RBO samples were analysed for their γ-oryzanol compositions using the new method.•The present method may serve as an alternative approach for rice bran oil analysis.A high performance liquid chromatography (HPLC) method was developed for simultaneous quantification of five major triterpene alcohol and sterol ferulates in rice bran oils (RBO) with a single internal standard, cycloartenyl ferulate. The five compounds are cycloartenyl ferulate (1), 24-methylene cycloartanyl ferulate (2), campesteryl ferulate (3), sitosteryl ferulate (4) and stigmastanyl ferulate (5). All five compounds had good linear concentration-measurement relationships (r2 ⩾ 0.9995) and possessed similar relative response factors. The relative deviation of this method was less than 2.5% for intra- and inter-day assays, and the average recovery varied from 95.1% to 99.4%. The new method was validated by comparing the amount of 24-methylene cycloartanyl ferulate (2) in 17 RBO samples obtained with this method and that with an external standard method. This method was also successfully applied to determine five major triterpene alcohol and sterol ferulates in 17 batches of RBO samples. The results demonstrated that the present method could be utilised for quality control of RBO since some of the reference standards are not commercially available.

Twenty-one caffeic acid phenethyl ester (CAPE) derivatives were synthesized, and characterized by IR, HR-MS, 1H and 13C NMR analyses. All compounds were evaluated for their cytoprotective effects against H2O2-induced cytotoxicity and neuritogenic activities in the neurite outgrowth in PC12 cells. Compounds 1 and 20 exhibited stronger cytoprotective activities than their parent compound CAPE at 4 nM. Compounds 1, 4, 12 and 13 showed potential neuritogenic activities at 0.5 nM, while compounds 19 and 20 induced neurite outgrowth at 10 nM. The results from this study suggested that CAPE and its derivatives may be potential functional food ingredients for the prevention of neurodegenerative diseases.

•A FIMS fingerprinting method was applied to differentiate four different types of G. pentaphyllum samples.•PCA and PLS-DA were used to analyze FIMS fingerprints.•Each sample could be efficiently differentiated and classified in 2 min.•Eleven characteristic ions were screened out for differentiation of G. pentaphyllum samples.In the present study, the feasibility and advantages of a flow-injection mass spectrometric (FIMS) fingerprinting method combined with chemometrics for quick differentiation and quality assessment of di- and tetraploid leaf and whole-plant Gynostemma pentaphyllum (Thunb.) Makino (Jiaogulan in Chinese) were investigated for the first time. The rapid FIMS fingerprinting method was applied to generate spectrometric fingerprints of four different types of G. pentaphyllum samples. Chemometrics, including principal component analysis (PCA) and partial least square discriminative analysis (PLS-DA), were used to analyze the fingerprints. The results showed that each sample could be effectively differentiated and classified in 2 min. Furthermore, eleven characteristic ions that played the most important roles for differentiating the four groups of G. pentaphyllum samples were screened out by loadings plot from PLS-DA.

Twenty-eight seed samples of 12 Plantago species were investigated for their chemical compositions and anti-inflammatory, cellular antioxidant, and radical scavenging properties. A new UPLC-UV procedure was developed and applied to quantify acteoside and geniposidic acid, the characteristic constituents of the genus Plantago. The amounts of acteoside and geniposidic acid ranged from 0.07 to 15.96 mg/g and from 0.05 to 10.04 mg/g in the tested samples, respectively. Furthermore, 26 compounds were tentatively identified by UPLC/Q-TOF-MS analysis. The Plantago samples significantly differed in their phytochemical compositions. The extracts of Plantago seeds also showed inhibitory effects on LPS-induced IL-1β, IL-6, and COX-2 mRNA expression in RAW 264.7 mouse macrophage cells. Additionally, significant variations were observed among different samples on cellular antioxidant activities in HepG2 cells, as well as DPPH and hydroxyl radical scavenging capacities. The results from this study may be used to promote the use of the genus Plantago in improving human health.

Jiaogulan, Gynostemma pentaphyllum (Thunb.) Makino, is one of the well-known botanical ingredients for functional foods and beverages. The present study developed a simple, rapid and effective HPLC procedure for simultaneous quantification of rutin and quercetin in jiaogulan. This study also investigated the chemical compositions including total phenolic contents (TPC), total flavonoid contents (TFC) and total saponin contents (TSC), and HPLC/UV/MS fingerprinting profiles of eleven commercial jiaogulan samples. In addition, the scavenging capacities against 2,2-diphenyl-1-picryhydrazyl (DPPH) and hydroxyl (HOSC) radicals were studied. The eleven jiaogulan samples had a TPC of 1.4–35.1 mg/g for MeOH and 6.3–52.3 mg/g for 50% acetone extracts; they had a TFC of 1.7–25.5 mg/g for MeOH and 3.8–50.3 mg/g for 50% acetone; and they had a TSC of 17.6–193.4 mg/g for MeOH and 24.9–681.2 mg/g for 50% acetone. The RDSC of these samples had a range of 5.7–148.7 μmol/g for MeOH and 33.6–416.8 μmol/g for 50% acetone extracts. The HOSC of these samples had a range of 122.1–1618.3 μmol/g for MeOH and 223.7–4113.0 μmol/g for 50% acetone extracts. In addition, quercetin-di-(rhamno)-hexoside, kaempferol 3-O-di-p-coumaroylhexoside, kaempferol 3-O-di-p-coumaroylhexoside, quercetin-rhamno-hexoside, rutin, kaempferol-rhamno-hexoside, kaempferol-3-O-rutinoside, quercetin and kaempferol were identified in the jiaogulan samples. Principle component analysis (PCA) classified the eleven jiaogulan samples into three groups. These results suggested the possible variation of commercial jiaogulan products in their chemical compositions and health properties, and a need of improved quality control and assurance mechanism.Highlights► Gynostemma pentaphyllum Makino (GP) is a botanical widely used in tea and food. ► Chemical composition and antioxidant capacity differed greatly in commercial G. pentaphyllum samples. ► Nine flavonoids were identified in these samples by HPLC/MS. ► Based on fingerprinting profiles, the samples could be classified into three groups by PCA.

The present study was conducted to isolate and characterize anti-inflammatory peptides from whey protein hydrolysates using alcalase. Nine subfractions were obtained after sequential purification by ultrafiltration, Sephadex G-25 gel (GE Healthcare, Uppsala, Sweden) filtration chromatography, and preparative HPLC. Among them, subfraction F4e showed the strongest inhibitory activity on interleukin-1β (IL-1β), cyclooxygenase-2, and tumor necrosis factor-α (TNF-α) mRNA expression in lipopolysaccharide-induced RAW 264.7 mouse macrophages. Eight peptides, including 2 new peptides—Asp-Tyr-Lys-Lys-Tyr (DYKKY) and Asp-Gln-Trp-Leu (DQWL)—were identified from subfractions F4c and F4e, respectively, using ultra-high performance liquid chromatography-quadrupole-time-of-flight mass spectrometry. Peptide DQWL showed the strongest inhibitory ability on IL-1β, cyclooxygenase-2, and TNF-α mRNA expression and production of IL-1β and TNF-α proteins at concentrations of 10 and 100 μg/mL, respectively. Additionally, DQWL treatment significantly inhibited nuclear factor-κB activation by suppressing nuclear translocation of nuclear factor-κB p65 and blocking inhibitor κB kinase phosphorylation and inhibitor κB degradation together with p38 mitogen-activated protein kinase activation. Our study suggests that peptide DQWL has anti-inflammatory potential; further confirmation using an in vivo model is needed.