Impact of Camellia japonica Bee Pollen Polyphenols on Hyperuricemia and Gut Microbiota in Potassium Oxonate-Induced Mice.

Camellia japonica bee pollen is one of the major types of bee pollen in China and exhibits antioxidant and anti-inflammatory activities. The aims of our study were to evaluate the effects and the possible mechanism of Camellia japonica bee pollen polyphenols on the treatment of hyperuricemia induced by potassium oxonate (PO). The results showed that Camellia japonica bee pollen ethyl acetate extract (CPE-E) owned abundant phenolic compounds and strong antioxidant capabilities. Administration with CPE-E for two weeks greatly reduced serum uric acid and improved renal function. It inhibited liver xanthine oxidase (XOD) activity and regulated the expression of urate transporter 1 (URAT1), glucose transporter 9 (GLUT9), organic anion transporter 1 (OAT1), organic cation transporter 1 (OCT1) and ATP-binding cassette superfamily gmember 2 (ABCG2) in kidneys. Moreover, CPE-E suppressed the activation of the toll-like receptor 4/myeloid differentiation factor 88/nuclear factor-κB (TLR4/MyD88/NF-κB) signaling pathway and nucleotide-binding oligomerization domain-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome in PO-treated mice, and related inflammatory cytokines were reduced. CPE-E also modulated gut microbiota structure, showing that the abundance of Lactobacillus and Clostridiaceae increased in hyperuicemic mice. This study was conducted to explore the protective effect of CPE-E on hyperuricemia and provide new thoughts for the exploitation of Camellia japonica bee pollen.

Evaluation of physicochemical properties of Qinling Apis cerana honey and the antimicrobial activity of the extract against Salmonella Typhimurium LT2 in vitro and in vivo.

Apis cerana honey collected from the Qinling Mountains in China has been widely used for its antimicrobial property in traditional Chinese medicine. However, its antibacterial mechanism against Salmonella Typhimurium LT2 is still uncertain. A total of 52 volatile components were identified using headspace-gas-chromatography-ion-mobility, and Qinling A. cerana honey exhibited more abundant aromas than monofloral honeys. The phenolic extracts of honey sample F exhibited the lowest minimum inhibitory concentration (5 mg/mL), and chlorogenic acid exhibited the highest (155.91 ± 0.79 mg/kg), followed by caffeic acid, and rutin. After being treated with the extract, cell membranes of S. Typhimurium LT2 significantly shrunk and further collapsed. The extract treatment on mice caused a significant decrease in S. Typhimurium LT2, and a dramatic increase in the potential prebiotic Lactobacillus in both the caecum and colon. The results demonstrate that the Qinling A. cerana honey extract could effectively inhibit S. Typhimurium in vitro and in vivo.

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.

Anti-Obesity and Gut Microbiota Modulation Effect of Secoiridoid-Enriched Extract from Fraxinus mandshurica Seeds on High-Fat Diet-Fed Mice.

Previously we conducted a phytochemical study on the seeds of Fraxinus excelsior and isolated nine secoiridoid compounds with adipocyte differentiation inhibitory activity and peroxisome proliferator activated receptor alpha (PPARα) activation effects. However, the bioactive constituents and functions of Fraxinus mandshurica seeds have not been studied. In the present study, we investigated the secoiridoid compounds in F. mandshurica seed extract (FM) using column chromatography, 1H-NMR, 13C-NMR and HPLC-DAD methods. The pancreatic lipase inhibitory activities of isolated compounds were evaluated in vitro. Additionally, the anti-obesity and gut microbiota modulation effect of FM on high-fat diet-induced obesity in C57BL/6 mice were also studied in vivo. The results showed that 19 secoiridoids were isolated from FM and identified. The total content of secoiridoids in FM reached 181.35 mg/g and the highest content was nuzhenide (88.21 mg/g). All these secoiridoid compounds exhibited good pancreatic lipase inhibitory activity with inhibition rate ranged from 33.77% to 70.25% at the concentration of 100 µM. After obese mice were administrated with FM at 400 mg/kg.bw for 8 weeks, body weight was decreased by 15.81%. Moreover, FM could attenuate the lipid accumulation in serum and liver, relieve the damage in liver and kidney, and extenuate oxidative stress injury and inflammation caused by obesity in mice. FM could also modulate the structural alteration of gut microbiota in obese mice, increasing the proportion of anti-obesity gut microbiota (Bacteroidetes, Bacteroidia, S24-7 and Allobaculum), and reducing the proportion of obesogenic gut microbiota (Firmicutes and Dorea). This study suggests that F. mandshurica seeds or their secoiridoids may have potential for use as a dietary supplement for obesity management.

Simultaneous characterization and quantification of flavonoids in Morus australis root as potential hepatoprotective nutraceutical.

Morus australis distributed widely in China has high value in food and agriculture. Twelve phenolic compounds were isolated and identified as major constituents of M. australis root from Shaanxi province, China, while the protective effect of M. australis root on liver injury has never been determined in detail. In this study, the hepatoprotective ability of M. australis root was investigated in vivo and in vitro. The ethanol-water extract prepared from M. australis root showed protection on alcohol-induced liver damage in mice by decreasing the levels of serum alanine aminotransferase, aspartate transaminase, triacylglycerol and malondialdehyde, and by increasing glutathione contents. Furthermore, among 12 major constituents of M. australis root, 10 flavonoids (especially 1) showed protection against carbon tetrachloride (CCl4 )-intoxicated HepG2 cell lines by decreased lactic dehydrogenase levels. In addition a validated HPLC-DAD method was established for the quantitative analysis of 10 flavonoids in the bioactive extract. PRACTICAL APPLICATIONS: Our results showed that M. australis root extract significantly alleviated the liver damage in mice. Ten flavonoids from the root of this plant exhibited protection on CCl4 -intoxicated HepG2 cell lines. This study suggests that Morus australis root has hepatoprotective potential as a promising supplement for the prevention and treatment of liver diseases.

Chemical characterization of the main bioactive polyphenols from the roots of Morus australis (mulberry).

Morus species, commonly known as mulberry, is widely distributed in China. The mulberry tree is a high-value plant in agriculture. Morus australis is one of the major Morus species growing in Northern China. However, the biological properties of the main constituents of M. australis roots were not well studied. In the present study, through extensive chromatographic and spectral analysis, 12 phenolic compounds were isolated and identified from the M. australis roots. Compounds 1, 2, 8, 9 and 12 were isolated from M. australis roots for the first time. Antitumor activities of these polyphenols were studied on the A549 cell line. Compounds 1, 5 and 6 exhibited cytotoxicity on A549 cells and induced apoptosis in A549 cells via the intrinsic mitochondrial pathway. They also mediated inhibition of autophagic flux contributed cell death via the PI3k/Akt/mTOR pathway. In order to explore more potential bioactivities of these isolates, α-glucosidase, acetylcholinesterase and tyrosinase inhibitory activities were studied, and the results demonstrated that the inhibitory activity of these polyphenols on enzymes was not defined by their basic structural skeletons, but by the substituted position.

Discrimination of Natural Mature Acacia Honey Based on Multi-Physicochemical Parameters Combined with Chemometric Analysis.

Honey maturity is an important factor in evaluating the quality of honey. We established a method for the identification of natural mature acacia honey with eighteen physicochemical parameters combined with chemometric analysis. The analysis of variance showed significant differences between mature and immature acacia honey in physicochemical parameters. The principal component analysis explained 82.64% of the variance among samples, and indicated that total phenolic content, total protein content, and total sugar (glucose, fructose, sucrose) were the major variables. The cluster analysis and orthogonal partial least squares-discriminant analysis demonstrated that samples were grouped in relation to the maturity coinciding with the results of the principal component analysis. Meanwhile, the 35 test samples were classified with 100% accuracy with the method of multi-physicochemical parameters combined with chemometric analysis. All the results presented above proved the possibility of identifying mature acacia honey and immature acacia honey according to the chemometric analysis based on the multi-physicochemical parameters.

Rape bee pollen alleviates dextran sulfate sodium (DSS)-induced colitis by neutralizing IL-1ß and regulating the gut microbiota in mice.

Colitis is a major chronic disease in today's society. Consumption of phenolic compounds can protect against colitis. We examined the phenolic compounds of rape bee pollen extract (RPE) and investigated its prevention of DSS-induced colitis in C57BL/6 mice. HPLC-DAD-ECD analysis showed that 7 phenolic compounds were tentatively identified in RPE, of which kaempferol had the highest content (19.87 mg/g), followed by sinapic acid and rosmarinic acid. RPE at 21.2 g/kg BW (HD - high-dose group) and 10.6 g/kg BW (LD - low-dose group) ameliorated colon shortening, spleen swelling and colon weight reduction, improved the structure of colonic villi, glandular structures and crypts, which was further confirmed by conventional histological assessment, and inhibited the activities of related inflammatory cytokines. In particular, IL-1ß expression was downregulated by approximately 90% compared with that of the model group. Additionally, treatment with RPE altered the gut microbial structure of mice with colitis, showing that the abundances of Allobaculum and Bacteroides were significantly reduced and the abundance of Lactobacillus was markedly increased. This study indicated that RPE could protect the colon from DSS-induced colitis by increasing antioxidant capacity, alleviating inflammation and regulating the gut microbiota. This paper was conducted to investigate the potent protective effects of RPE treatments on a mouse model of colitis and provided new ideas for the application of rape bee pollen.

Impact of SchisandraChinensis Bee Pollen on Nonalcoholic Fatty Liver Disease and Gut Microbiota in HighFat Diet Induced Obese Mice.

Schisandrachinensisbee pollen has been used as a health food in China for centuries; however, its bioactive constituents and functions are not very clear. In this study, we investigated the phenolic compounds of Schisandrachinensisbee pollen extract (SCPE) by UHPLC-Q-Orbitrap-HRMS/HPLC-DAD-ECD and its prevention from nonalcoholic fatty liver disease (NAFLD) and modulation of gut microbiota in high fat diet induced obese C57BL/6 mice. The results showed that 12 phenolic compounds were identified in SCPE, and naringenin, rutin and chrysin were the main constituents. The content of naringenin reached 1.89 mg/g, and total phenolic content (TPC) of SCPE were 101.83 mg GA/g. After obese mice were administrated with SCPE at 7.86 and 15.72 g/kg BW for 8 weeks, body weight gains were reduced by 18.23% and 19.37%. SCPE could decrease fasting blood glucose, cut down the lipid accumulation in serum and liver, lessen oxidative injury and inflammation in obesity mice. Moreover, SCPE could effectively inhibit the formation of NAFLD by inhibition of LXR-α, SREBP-1c and FAS genes expression, and modulate the structural alteration of gut microbiota in obesity mice. These findings suggested that SCPE could attenuate the features of the metabolism syndrome in obesity mice, which can be used to prevent obesity and NAFLD of human beings.

Hepatoprotective Effects of the Honey of Apis cerana Fabricius on Bromobenzene-Induced Liver Damage in Mice.

Apis cerana honey (honey of Apis cerana Fabricius), widely distributed in the mountain areas of East Asia, has not been studied fully. The hepatoprotective activity of A. cerana honey was evaluated against bromobenzene-induced liver damage in mice. In high dose, A. cerana honey can significantly alleviate liver injury, as is indicated by the depressed levels of serum alanine aminotransferase (ALT) (59.13%) and aspartate aminotransferase (AST) (79.71%), the inhibited malondialdehyde (MDA) content (63.30%), the elevated activities of superoxide dismutase (SOD) (73.12%) and glutathione-Px (57.24%), and the decreased expression of Transforming growth factor ß1 (51.83%) induced by bromobenzene (P < 0.05). The quantitative analysis of twelve major constituents (1 to 12) of A. cerana honey was executed by high performance liquid chromatography-diode array detector. The results indicate that treatment with A. cerana honey can prevent bromobenzene-induced hepatic damage in mice. Polyphenols might be the bioactive substances attributed to its antioxidant properties and intervention of oxidative stress.