3α-Hydroxylup-20(29)-ene-23,28-dioic Acid as a Phytogenic Chemical Marker for Authenticating Schefflera octophylla (Lour.) Harms Monofloral Honey.

The monofloral honey from Schefflera octophylla (Lour.) Harms (MH-Sco) are of high economic value due to their rarity and potential medicinal benefits. However, the limited investigations on the relationship of phytogenic components between the plant S. octophylla (P-Sco) and MH-Sco have an impact on MH-Sco authentication. Herein, the tentative phytogenic markers of MH-Sco were screened by comparing the metabolites of MH-Sco obtained by ultrahigh-performance liquid chromatography-quadrupole time-of-flight tandem mass spectrometry (UHPLC-Q-TOF-MS/MS)-based untargeted metabolomics with the identified phytogenic chemicals from P-Sco. Combined with the mass and NMR spectral information, 3α-hydroxylup-20(29)-ene-23,28-dioic acid (HLEDA) was finally identified as the phytogenic marker of MH-Sco. A targeted ultrahigh-performance liquid chromatography-triple quadrupole mass spectrometry (UHPLC-QqQ-MS/MS)-based method was established and validated based on the purified monomer standard to measure HLEDA levels in honey samples. HLEDA determined in MH-Sco was with the content from 0.303 to 0.440 mg/kg, while HLEDA was absent in honey samples from other botanical origins, indicating the reliability of HLEDA as a chemical marker in MH-Sco authentication. This study provides the theoretical basis and industry guidance for honey quality control for commercial consumption.

Fu Loose Tea Administration Ameliorates Obesity in High-Fat Diet-Fed C57BL/6J Mice: A Comparison with Fu Brick Tea and Orlistat.

Fu tea is receiving increasing attention for its specific aroma, flavor, and dramatic functional benefits. Herein, we explored the effects and underlying mechanisms of Fu loose tea (FLT), Fu brick tea (FBT), and diet pills (orlistat) on a high-fat diet (HFD)-induced obesity. The results indicated that FLT and FBT administration effectively inhibited weight gain, glucose metabolic dysregulation, fat accumulation in organs, hepatic and kidney injury, and oxidative stress induced by HFD. Additionally, FLT and FBT treatments improved the lipid profiles and reduced the production of proinflammatory cytokines by regulating the expression levels of lipid metabolism- and inflammation-related genes. Furthermore, FLT and FBT ameliorated the gut microbiota dysbiosis in HFD-mice in a dose-dependent relationship by increasing the abundance of family Verrucomicrobiaceae and genus Akkermansia and Turicibacter and simultaneously reducing the abundance of family Erysipelotrichaceae and genus Bifidobacterium; in contrast, orlistat did not exert a regulatory effect on gut microbiota similar to FLT and FBT to improve HFD-induced obesity. KEGG analysis of gut microbiota annotation revealed that "metabolism" was the most enriched category. This study further provides a theoretical basis for FLT and FBT to be potential supplements to alleviate diet-induced obesity.

A High-Performance Liquid Chromatography with Electrochemical Detection Method Developed for the Sensitive Determination of Ascorbic Acid: Validation, Application, and Comparison with Titration, Spectrophotometric, and High-Performance Liquid Chromatography with Diode-Array Detection Methods.

L-ascorbic acid (vitamin C, VC), an essential nutrient obtained from the diet to maintain various vital signs for the human body, is a crucial indicator of food quality and nutritional value. Herein, high-performance liquid chromatography with electrochemical detection (HPLC-ECD) was developed and validated with the advantages of higher sensitivity, simpler operation processes, and more rapid detection in measuring VC levels in honey samples when compared with the common methods (titration, spectrophotometric, and HPLC-DAD methods). The results of the HPLC-ECD methodological validation showed that the limit of detection (LOD) was 0.0043 µg mL-1; the relative standard deviations (RSDs) of the intra- and inter-day values were between 2.51% and 5.15%, and the regression coefficient was >0.999 in the linear range of 0.1 to 20 µg mL-1. The validated HPLC-ECD method was also successfully utilized to evaluate the VC levels in different varieties of honey samples with various storage durations as well as in fruit and biological samples. This study provided a perspective for the further accurate determination of VC content in food and biological samples.

Hydroxy Fatty Acids as Novel Markers for Authenticity Identification of the Honey Entomological Origin Based on the GC-MS Method.

The authenticity of honey is generally a worldwide concern, and there is a pressing need to establish a suitable entomological method to identify the authenticity of Apis cerana cerana (A. cerana) and Apis mellifera ligustica (A. mellifera) honey. Hydroxy fatty acids as bee-derived components are known to widely exist in honey and other biosamples. Herein, we present an identification strategy for hydroxy fatty acids based on the relative quantification with reference to royal jelly and targeted quantification combined with multivariate statistical analysis to identify the honey entomological origin. Multivariate statistical analysis was used to further determine differential hydroxy fatty acids between A. cerana honey and A. mellifera honey. Results showed that 8-hydroxyoctanoic acid (96.20-253.34 versus 0-32.46 mg kg-1) and 3,10-dihydroxydecanoic acid (1.96-6.56 versus 0-0.35 mg kg-1) could be used as markers for accurate identification of the honey entomological origin, while the three fraud honey samples were recognized using this method. This study provides the novel marker hydroxy fatty acids to identify A. cerana honey and A. mellifera honey from the perspective of bee-derived component differences.

Natural crystallization properties of honey and seed crystals-induced crystallization process for honey performance enhancing.

Honey crystallization is a common occurrence, while the underlying mechanisms are not clear. Here we evaluated natural crystallization and induced crystallization of honey. By using the method of microscopy, colorimetry, rheology, texture, and calorimetry to investigate the main physical and structural properties and compare with honey seed crystals-induced crystallization in six unifloral honey. The results showed honey transformed into a pseudoplastic fluid during natural crystallization, with the increase of L-value, firmness and cohesiveness and the fastest crystallization rate occurring at 14 °C and water content of 16%. The effect of the addition of seed crystals in the honey crystallization can be summarized as the acceleration of crystallization rate (3 times) and the improvement of crystallization characteristics including uniform particles and reducing stratification. This study provides insight into honey crystallization theory and a resource for the further exploration and development of the new performance of honey products.

Alternative to Sugar, Honey Does Not Provoke Insulin Resistance in Rats Based on Lipid Profiles, Inflammation, and IRS/PI3K/AKT Signaling Pathways Modulation.

Insulin resistance (IR) is the central link to metabolic syndrome (MS), and IR prevention has become the key to overcoming this worldwide public health problem. A diet rich in simple sugars is an important pathogenic factor in IR development. To investigate the effect of honey on IR compared to the sugar-water diet, we analyzed phenolics and oligosaccharides in jujube honey and rape honey based on LC-MS and silane derivatization/GC-MS. The effects of different diets on glucose and lipid profile, histopathology and IR-related mechanism pathways were analyzed and compared by equal sugar levels intervention of fructose, fructose + glucose and two kinds of unifloral honey (high-/low-dose) in rats. The results suggested that sugar-equivalent honey, which differs from sugar solution, especially 17.1 g/kg BW jujube honey rich in phenolics (1.971 mg/100 g of isoquercitrin) and oligosaccharides (2.18 g/100 g of turanose), suppressed IR via maintaining glucose (OGTT and ITT) and lipid (TC, TG, LDL-C, HDL-C, and NEFA) homeostasis, improving histological structural abnormalities of the liver, adipose and skeletal muscle, reducing oxidative stress (GSH-Px and MDA) and inflammation (IL-6 and TNF-α), modulating the NF-κB (NF-κB gene expression was down-regulated to 0.94) and IRS/PI3K/AKT signaling pathways (e.g., AKT and GLUT2 expression in liver increased by 4.56 and 13.37 times, respectively) as well as reshaping the gut microbiota. These revealed a potential nutritional contribution of substituting honey for simple sugar in the diet, providing a theoretical basis for controlling IR development via dietary modification and supplementation.

Volatile compounds of five types of unifloral honey in Northwest China: Correlation with aroma and floral origin based on HS-SPME/GC-MS combined with chemometrics.

Discrimination of floral origin and its complemented aroma features is important for honey authentication. In this study, a comprehensive analysis of five unifloral honeys was analyzed based on the correlation between volatile compounds and aroma and floral origin using HS-SPME/GC-MS combined with chemometrics. A total of 92 volatiles were identified and relatively quantified in honey samples, 51 of which showed contribution to floral discrimination (p < 0.01), and 27 of which had aroma contribution, applying apocynum, jujube and amorpha honey with various fruity, elaeagnus with rosaceous and lavender with green flavor. Chemometrics analysis showed significant correlations between floral origin and volatiles, in particular, compounds hexanal, hexanol, heptanol and methyl enanthate were tentatively selected as the key compounds to discriminate lavender honey (Lavandula angustifolia Mill.) from others. These results reveal the volatiles and aroma features in five types of unifloral honey in Northwest China and offer compelling evidence for honey authentication.

ICP-MS-based ionomics method for discriminating the geographical origin of honey of Apis cerana Fabricius.

The identification of geographical origin is an important factor in evaluating the authenticity of honey. However, at present, there are few studies concerning the honey of Apis cerana Fabricius (A. cerana, Asiatic honeybee). To identify geographical origin, we used two common methods (multi-physicochemical parameters and phenolic chromatographic fingerprints) but achieved only poor identification. To compensate for this shortcoming, we established an ICP-MS-based ionomics method using 18 elements in 27 A. cerana honey samples from three different areas in Shaanxi Province, China. Multivariate analysis showed that significant differences in contents can be used to discriminate the geographical origin of A. cerana honey. The method was further validated using an independent test set of 11 samples with 90.91% accuracy, demonstrating its potential for the identification and prediction of the geographical origin of honey.

Molecular Mechanism of Mature Honey Formation by GC-MS- and LC-MS-Based Metabolomics.

Honey maturity is an important factor in evaluating the quality of honey; however, there are few studies on the molecular mechanism of the formation of mature honey (MH). In this study, the different metabolites of stomach honey (SH), immature honey (IMH), and MH samples during the same rapeseed flower season were analyzed by an UPLC-QTOF-MS-based metabolomics approach. MH was found to have a distinct metabolic profile to IMH, and a total of 9 different metabolites were obtained, 3 of which, including decenedioic acid, were accumulated in MH. Decenedioic acid as a bee-originated fatty acid (FA) was further verified in rape, acacia, and jujube honey by GC-MS, making it a potential marker to discriminate IMH and MH (P < 0.01). Besides, MH showed higher FAs concentrations; in particular, 3 FAs were significantly richer in MH than IMH (P < 0.05). This study reveals the molecular mechanism from IMH to MH from a FA perspective.

A Novel Chinese Honey from Amorpha fruticosa L.: Nutritional Composition and Antioxidant Capacity In Vitro.

False indigo (Amorpha fruticosa L., A. fruticosa) is the preferred tree indigenous for windbreak and sand control in Northwest China, while information on nutritional and bioactive characteristics of its honey is rare. Herein, 12 honey of Amorpha fruticosa L. (AFH) were sampled in Northwest China and the nutritional composition was determined. Sixteen mineral element and ten dominant polyphenols content were identified and quantified by ICP-MS (Inductively coupled plasma mass spectrometry) and HPLC-QTOF-MS (High performance liquid chromatography-Quadrupole time-of-flight mass spectrometry), respectively. Moreover, AFH demonstrated high levels of DPPH (1,1-Diphenyl-2-picrylhydrazyl) radical scavenging activity (IC50 100.41 ± 15.35 mg/mL), ferric reducing antioxidant power (2.04 ± 0.29 µmol FeSO4·7H2O/g), and ferrous ion-chelating activity (82.56 ± 16.01 mg Na2EDTA/kg), which were significantly associated with total phenolic contents (270.07 ± 27.15 mg GA/kg) and ascorbic acid contents (213.69 ± 27.87 mg/kg). The cell model verified that AFH exhibited dose-dependent preventive effects on pBR322 plasmid DNA and mouse lymphocyte DNA damage in response to oxidative stress. Taken together, our findings provide evidence for the future application of AFH as a potential antioxidant dietary in food industry.

An Integrated Structural Air Electrode Based on Parallel Porous Nitrogen-Doped Carbon Nanotube Arrays for Rechargeable Li-Air Batteries.

The poor discharge and charge capacities, and the cycle performance of current Li-air batteries represent critical obstacles to their practical application. The fabrication of an integrated structural air electrode with stable parallel micropore channels and excellent electrocatalytic activity is an efficient strategy for solving these problems. Herein, a novel approach involving the synthesis of nitrogen-doped carbon nanotube (N-CNT) arrays on a carbon paper substrate with a conductive carbon-black layer for use as the air electrode is presented. This design achieves faster oxygen, lithium ion, and electron transfer, which allows higher oxygen reduction/evolution reaction activities. As a result, the N-CNT arrays (N/C = 1:20) deliver distinctly higher discharge and charge capacities, 2203 and 186 mAh g-1, than those of active carbons with capacities of 497 and 71 mAh g-1 at 0.05 mA cm-2, respectively. A theoretical analysis of the experimental results shows that the parallel micropore channels of the air electrode decrease oxygen diffusion resistance and lithium ion transfer resistance, enhancing the discharge and charge capacities and cycle performance of Li-air batteries. Additionally, the N-CNT arrays with a high pyridinic nitrogen content can decompose the lithium peroxide product and recover the electrode morphology, thereby further improving the discharge-charge performance of Li-air batteries.