Haiming Shi

Isolation and characterization of two flavonoids, engeletin and astilbin, from the leaves of Engelhardia roxburghiana and their potential anti-inflammatory properties.

Engeletin, a flavonoid compound, was isolated from the leaves of Engelhardia roxburghiana for the first time, along with astilbin, another flavonoid. The chemical structures of engeletin and astilbin were confirmed by (1)H and (13)C nuclear magnetic resonance (NMR) and mass spectrometry (MS) spectra, and their anti-inflammatory activities were studied in lipopolysaccharide (LPS)-stimulated mouse J774A.1 macrophage cells. LPS induced the inflammatory state in macrophage cells and increased mRNA expressions of pro-inflammatory cytokines. Engeletin and astilbin exhibited remarkable inhibitory effects on interleukin (IL)-1β and IL-6 mRNA expression. Significant inhibition of LPS-mediated mRNA expressions were also seen in LPS binding toll-like receptor (TLR)-4, pro-inflammatory cytokine tumor necrosis factor (TNF)-α, IL-10, chemoattractant monocyte chemotactic protein (MCP)-1, and cyclooxygenase (COX)-2 genes. The reduced expression of these cytokines may alleviate immune response and reduce inflammatory activation, indicating that engeletin and astilbin may serve as potential anti-inflammatory agents.

Chemical profiling of triacylglycerols and diacylglycerols in cow milk fat by ultra-performance convergence chromatography combined with a quadrupole time-of-flight mass spectrometry.

An ultra-performance convergence chromatography (UPC(2)) 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, UPC(2) is an environmental friendly analytical method with a drastic reduction of organic solvent usage. The established UPC(2)-MS approach has potential application in lipidomics as an alternative method besides LC-MS and GC-MS.

Antioxidant properties and phytochemical composition of China-grown pomegranate seeds

Four cultivars of Shanxi-grown pomegranate seeds were investigated for their phytochemical composition and antioxidant properties. Pomegranate seed oils were extracted and analysed for their fatty acid profiles, and tocopherol and carotenoid contents. The defatted flours were extracted with 50% acetone or 80% methanol, and evaluated for levels of phenolics, flavonoids and proanthocyanidins, and scavenging capacities against DPPH and ABTS+ and their ferric ion reducing abilities. Pomegranate seed oil was rich in punicic acid (73.5-78.8g/100g oil) and total tocopherols (5.3-12.0μmol/g). The 50% acetone and 80% methanol were appropriate solvents for extraction of total phenolic and total flavonoid, respectively. The four cultivars were significantly different in levels of phenolics, flavonoids, proanthocyanidins and their antioxidant properties (P<0.05), generally flowing an order: Suanshiliu>Tianhongdan>Sanbaitian≈Jingpitian. This study will assist in the cultivar selection of the above pomegranate seeds for commercial production to meet the market demand.

Phenolic composition and nutraceutical properties of organic and conventional cinnamon and peppermint

Conventional and organic cinnamon and peppermint were investigated for their phenolic profile, anti-proliferative, anti-inflammatory, and antioxidant properties. Accelerated solvent extraction with 75% acetone was used to extract samples. Caffeic acid was the most abundant phenolic acid in peppermint. Catechin, (-)-epigallocatechin gallate, syringic acid, gallic acid, vanillic acid, and p-coumaric acid were also detected in both spices. There was no significant difference between conventional and organic spices in the composition of most individual phenolics. All conventional and organic peppermint and cinnamon extracts exhibited strong anti-proliferative and anti-inflammatory properties. Cinnamon was more efficient in inhibiting IL-1β and COX-2 expression, while peppermint showed better inhibitory effect on IL-6 and MCP-1. This study indicates that cinnamon and peppermint may potentially be used as dietary sources of bioactive phytochemicals for improving health.

Acute oral toxicity of 3-MCPD mono- and di-palmitic esters in Swiss mice and their cytotoxicity in NRK-52E rat kidney cells.

The acute oral toxicity of 1-palmitoyl-3-chloropropanediol (3-MCPD 1-monopalmitate) and 1,2-bis-palmitoyl-3-chloropropanediol (3-MCPD dipalmitate) in Swiss mice were examined, along with their cytotoxicity in NRK-52E rat kidney cells. LD50 (median lethal dose) value of 3-MCPD 1-monopalmitate was determined 2676.81 mg/kg body weight (BW). The results showed that 3-MCPD 1-monopalmitate dose-dependently decreased the mean body weight, and caused significant increase of serum urea nitrogen and creatinine in dead mice compared to the control and survived mice. Major histopathological changes in mice fed 3-MCPD 1-monopalmitate were renal tubular necrosis, protein casts and spermatids decrease in the seminiferous tubules. According to the limit test for 3-MCPD dipalmitate, LD50 value of 3-MCPD dipalmitate was presumed to be greater than 5000 mg/kg BW. Obvious changes were not observed on mean body weight, absolute and relative organ weight or serum urea nitrogen and creatinine levels in mice fed 3-MCPD dipalmitate. However, renal tubular necrosis, protein casts and spermatids decrease were also observed in the dead mice. In addition, MTT and LDH assay results only showed the cytotoxicity of 3-MCPD 1-monopalmitate in NRK-52E rat kidney cells in a dose-dependent manner. Together, the results indicated a greater toxicity of 3-MCPD 1-monopalmitate compared to 3-MCPD dipalmitate.

Identification and Quantification of Phytochemical Composition and Anti-inflammatory and Radical Scavenging Properties of Methanolic Extracts of Chinese Propolis

Fifteen propolis samples collected from different regions of China were investigated and compared for their phytochemical composition and anti-inflammatory and radical scavenging properties. Eleven compounds including caffeic, p-coumaric, ferulic, isoferulic, and 3,4-dimethylcaffeic acids, pinobanksin, chrysin, pinocembrin, galangin, pinobanksin 3-acetate, and caffeic acid phenylethyl ester were quantified for the 15 propolis samples using a UHPLC method, whereas 38 compounds were identified by UPLC/Q-TOF-MS. The 15 propolis samples significantly differed in their total phenolic and total flavonoid contents, as well as their phytochemical profiles. The methanol extracts of propolis also showed significant anti-inflammatory effects in LPS-stimulated RAW 264.7 mouse macrophage cells at 10 μg propolis extract/mL concentration. Additionally, the propolis samples differed in their DPPH, ABTS cation, hydroxyl, and peroxide radical scavenging capacities and ferric reducing abilities. The results from this study may be used to improve the commercial production and consumption of Chinese propolis products.

Identification and Quantification of Phytochemical Composition and Anti-inflammatory, Cellular Antioxidant, and Radical Scavenging Activities of 12 Plantago Species

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.

Chemical composition and anti-proliferative and anti-inflammatory effects of the leaf and whole-plant samples of diploid and tetraploid Gynostemma pentaphyllum (Thunb.) Makino

Leaf and whole-plant samples of the diploid and tetraploid Gynostemma pentaphyllum (GP) were investigated and compared for their chemical compositions, and their potential anti-proliferative and anti-inflammatory effects. The highest levels of total flavonoids and phenolics were observed in the diploid leaf botanical (2L3) at 36.84mg rutin equiv/g and 41.15mg gallic acid equiv/g, respectively. The diploid leaf sample (2L2) had the highest amount of rutin and quercetin contents of 77.7μmol quercetin equiv/g. The tetraploid whole-plant botanical (4L3) had the highest total saponin content of 227.1mg gypenoside equiv/g. Extracts from all tested GP samples showed time- and dose-dependent antiproliferative effects in HT-29 cells, and the diploid leaf samples had the overall highest inhibitory activity. These extracts had different order of antiproliferative properties in the LNCaP cells, suggesting the potential selective inhibition of GP extracts against different types of cancer cells and the effect of the cell model in screening and evaluation of antiproliferative components. In addition, the diploid leaf extracts showed the strongest inhibitory effects on the expression of TNF-α, IL-6 and COX-2 mRNA at final concentrations of 0.2 and 1mg botanical equiv/ml media. The results from this study will be used to develop new nutraceutical products from G. pentaphyllum.

Two new saponins from tetraploid jiaogulan (Gynostemma pentaphyllum), and their anti-inflammatory and α-glucosidase inhibitory activities

Jiaogulan tea has been commercialised globally. This study investigated the chemical components and health properties of a new jiaogulan genotype, tetraploid Gynostemma pentaphyllum. Two new saponins, (23S)-21β-O-methyl-3β,20ξ-dihydroxy-12-oxo-21,23-epoxydammar-24-ene-3-O-[α-L-rhamnopyranosyl(1→2)][β-D-glucopyranosyl(1→3)]-α-L-arabinopyranoside (4) and 23β-H-3β,20ξ-dihydroxy-19-oxo-21,23-epoxydammar-24-ene-3-O-[α-L-rhamnopyranosyl(1→2)][β-D-xylopyranosyl(1→3)]-α-L-arabinopyranoside (5), together with one lactone, 3,5-dihydroxyfuran-2(5H)-one (1), and two flavonoids, rutin (2) and kaempferol 3-O-rutinoside (3), were characterised in the aerial parts of tetraploid jiaogulan. The chemical structures of the five isolated compounds were elucidated by NMR, HR-MS spectra and chemical degradation. The five compounds were also examined and compared with the methanol extract and n-butanol soluble fraction of the jiaogulan for their inhibitory activities on lipopolysaccharide (LPS)-induced IL-1β, IL-6 and COX-2 mRNA expression in RAW 264.7 mouse macrophages, and their in vitro α-glucosidase suppressing capacities. The results from this study may be used to promote the potential application of jiaogulan in functional foods.

Partial Least-Squares-Discriminant Analysis Differentiating Chinese Wolfberries by UPLC–MS and Flow Injection Mass Spectrometric (FIMS) Fingerprints

Lycium barbarum L. fruits (Chinese wolfberries) were differentiated for their cultivation locations and the cultivars by ultraperformance liquid chromatography coupled with mass spectrometry (UPLC-MS) and flow injection mass spectrometric (FIMS) fingerprinting techniques combined with chemometrics analyses. The partial least-squares-discriminant analysis (PLS-DA) was applied to the data projection and supervised learning with validation. The samples formed clusters in the projected data. The prediction accuracies by PLS-DA with bootstrapped Latin partition validation were greater than 90% for all models. The chemical profiles of Chinese wolfberries were also obtained. The differentiation techniques might be utilized for Chinese wolfberry authentication.