The ethanol extract of Osmanthus fragrans attenuates Porphyromonas gingivalis lipopolysaccharide-stimulated inflammatory effect through the nuclear factor erythroid 2-related factor-mediated antioxidant signalling pathway

Effect of Isolated Scenting Process on the Aroma Quality of Osmanthus Longjing Tea

Scenting is an important process for the formation of aroma quality in floral Longjing tea. There are differences in the aroma quality of osmanthus Longjing teas processed by different scenting processes. The efficient isolated scenting method was employed to process a new product of osmanthus Longjing tea in this study, and this was compared with the traditional scenting method. The volatile compounds of osmanthus Longjing tea were analyzed by a GC-MS instrument. In addition, the effects of scenting time and osmanthus consumption on the aroma quality of Longjing tea were studied. The results indicated that there were 67 kinds of volatile compounds in the osmanthus Longjing tea produced by the isolated scenting process (O-ISP), osmanthus Longjing tea produced by the traditional scenting process (O-TSP), and raw Longjing tea embryo (R), including alcohols, ketones, esters, aldehydes, olefins, acids, furans, and other aroma compounds. The proportions of alcohol compounds, ester compounds, aldehyde compounds, and ketone compounds in O-ISP were higher than in O-TSP and R. When the osmanthus consumption was increased, the relative contents of volatile aroma compounds gradually increased, which included the contents of trans-3,7-linalool oxide II, dehydrolinalool, linalool oxide III (furan type), linalool oxide IV (furan type), 2,6-Dimethyl cyclohexanol, isophytol, geraniol, 1-octene-3-alcohol, cis-2-pentenol, trans-3-hexenol, β-violet alcohol, 1-pentanol, benzyl alcohol, trans-p-2-menthene-1-alcohol, nerol, hexanol, terpineol, 6-epoxy-β-ionone, 4,2-butanone, 2,3-octanedione, methyl stearate, cis-3-hexenyl wasobutyrate, and dihydroanemone lactone. When the scenting time was increased, the relative contents of aroma compounds gradually increased, which included the contents of 2-phenylethanol, trans-3,7-linalool oxide I, trans-3,7-linalool oxide II, dehydrolinalool, isophytol, geraniol, trans-3-hexenol, β-ionol, benzyl alcohol, trans-p-2-menthene-1-ol, nerol, hexanol, terpineol, dihydroβ-ionone, α-ionone, and β-ionone,6,10. The isolated scenting process could achieve better aroma quality in terms of the floral fragrance, refreshing fragrance, and tender fragrance than the traditional scenting process. The isolated scenting process was suitable for processing osmanthus Longjing tea with high aroma quality. This study was hoped to provide a theoretical base for the formation mechanism and control of quality of osmanthus Longjing tea.

Moisture content of tea dhool for the scenting process affects the aroma quality and volatile compounds of osmanthus black tea

To improve the quality of osmanthus black tea, samples produced with different scenting methods were prepared. The sensory quality was assessed and the characteristic aromatic components were explored using solid-phase microextraction (SPME) coupled with gas chromatography-mass spectrometry. According to the results, osmanthus black tea obtained by adding osmanthus scenting in the fermentation process had the strongest floral aroma. The major contributors to the aroma of osmanthus black tea were identified as β-ionone, dihydro-β-ionone, benzeneacetaldehyde, citral, geraniol, and linalool by calculating their relative odor activity values. An analysis of the causes revealed that the moisture content of tea dhool significantly affected the adsorption of fresh flower aroma by tea. The experimental results showed that osmanthus black tea produced using tea dhool containing 30% moisture content had the highest content of crucial aroma components, suggesting the tea dhool under this condition had the strongest adsorption capacity for osmanthus aroma.

The relationship with and effect of oral microbiota on NLRP3 inflammatory pathway in type 2 diabetes mellitus

OBJECTIVE

The aim of this study was to explore the correlation between oral microbiota and NLRP3 inflammasome in type 2 diabetes, and to preliminarily explore their possible impact on type 2 diabetes.

DESIGN

The 16S rDNA sequencing technique was used to analyze the microbial composition in the saliva of patients with T2DM and healthy people. Real-time quantitative PCR (RT-qPCR) was used to detect the expression levels of T2DM-related inflammatory cytokines in the blood of two groups.

RESULTS

The relative abundances of Fusobacteriota and Campilobacterota in the saliva of patients with T2DM were lower than those of healthy people (P < 0.05), whereas the relative abundance of Proteobacteria in patients with T2DM was higher than that of healthy people (P < 0.05). In addition, real-time quantitative PCR results showed changes in inflammasome-associated factors in the blood of patients with T2DM and healthy people. Compared with healthy individuals, the relative expression levels of lipopolysaccharide (LPS), apoptosis-associated point-like protein (ASC), Caspase-1, Caspase-11, nucleotide-binding oligomerization domain-like receptor family pyrin domain containing 3 (NLRP3), and interleukin (IL)-1β were significantly higher in the blood of patients with T2DM, whereas the expression level of insulin receptor substrate-1 (IRS-1) was reduced (P < 0.05).

CONCLUSIONS

Our research suggested that changes in the ratio of oral microbial taxa might increase the expression levels of inflammatory and T2DM-related factors by activating the NLRP3 inflammasome pathway. This discovery indicated the imbalance in oral microbiota might have a certain influence on diabetes by triggering an inflammatory response, and provided a new idea for the relationship between T2DM and oral microbiota.

Glycolipid-enriched fraction of Osmanthus fragrans inhibits LPS-induced expression of inflammatory genes, COX-2, E-selectin, and Interleukin-8

ETHNOPHARMACOLOGICAL RELEVANCE

Osmanthus fragrans Lour. is a small ornamental tree native to the Southeastern parts of China. It is mainly cultivated because of its characteristic fragrance, and used in the food and perfume industry. Besides, its flowers are used in traditional Chinese medicine to treat a variety of diseases including those related to inflammation.

AIM OF THE STUDY

The aim of the study was to investigate in more detail the anti-inflammatory properties of O. fragrans flowers, and to characterize their active principles and mechanisms of action.

MATERIALS AND METHODS

O. fragrans flowers were successively extracted with n-hexane, dichloromethane and methanol. The extracts were further fractionated by chromatographic separation. COX-2 mRNA expression in PMA-differentiated, LPS-stimulated THP-1 cells was used as lead assay for activity-guided fractionation. The most potent fraction was chemically analyzed by LC-HRMS. The pharmacological activity was also evaluated in other inflammation-related in-vitro models, such as analysis of IL-8 secretion and E-selectin expression in HUVECtert cells and selective inhibition of COX-isoenzymes.

RESULTS

n-Hexane and dichloromethane extracts of O. fragrans flowers significantly inhibited COX-2 (PTGS2) mRNA expression. Additionally, both extracts inhibited COX-2 enzyme activity, whereas COX-1 enzyme activity was affected to a significantly lower extent. Fractionation of the extracts led to a highly active, glycolipid-containing fraction. In total, 10 glycolipids were tentatively annotated by LC-HRMS. This fraction also inhibited LPS-induced COX-2 mRNA expression, IL-8 secretion and E-selectin expression. The effects were limited to LPS-induced inflammation and not observed when inflammatory genes were induced by TNF-α, IL-1β or FSL-1. Since all these inducers of inflammation act via different receptors, it is likely that the fraction interferes with the binding of LPS to the TLR4-receptor, which mediates pro-inflammatory effects of LPS.

CONCLUSION

Taken together, the results demonstrate the anti-inflammatory potential of O. fragrans flower extracts in general, and of the glycolipid-enriched fraction in particular. The effects of glycolipid-enriched fraction are potentially mediated via the inhibition of the TLR4 receptor complex.

Edible Osmanthus fragrans flowers: aroma and functional components, beneficial functions, and applications

Osmanthus fragrans (O. fragrans) has been cultivated in China for over 2,500 years as a traditional fragrant plant. Recently, O. fragrans has drawn increasing attention due to its unique aroma and potential health benefits. In this review, the aroma and functional components of O. fragrans are summarized, and their biosynthetic mechanism is discussed. The beneficial functions and related molecular mechanism of O. fragrans extract are then highlighted. Finally, potential applications of O. fragrans are summarized, and future perspectives are proposed and discussed. According to the current research, O. fragrans extracts and components have great potential to be developed into value-added functional ingredients with preventive effects on certain chronic diseases. However, it is crucial to develop efficient, large-scale, and commercially viable extraction methods to obtain the bioactive components from O. fragrans. Furthermore, more clinical studies are highly needed to explore the beneficial functions of O. fragrans and guide its development into functional food products.

The effects and underlying mechanisms of medicine and food homologous flowers on the prevention and treatment of related diseases

The theory of medicine and food homology has a long history in China. Numerous traditional Chinese medicinal could be used as both medicine and food. Many flower medicinal materials also belong to the homology of medicine and food, such as Chrysanthemum morifolium, Lonicera japonica, Crocus sativus, and Lonicera macranthoides. They mainly contain flavonoids, organic acids, terpenoids, and other active ingredients, which have a variety of medicinal values, including anti-inflammatory, anti-tumor, and antioxidant. There are many formulations and functional foods containing these plants in Chinese medicine, which have a variety of nutritional and health effects on the human body. In this review, 10 widely used flowers were selected to review their pharmacological activities, prevention and treatment of related diseases and underlying mechanisms, and discussed the current limitations and future development prospects, hoping to provide references for the research on the development and utilization of natural medical flowers. PRACTICAL APPLICATIONS: The "homology of medicine and food" flowers have a wide range of uses and are of great research value. In this paper, we introduce 10 "homology of medicine and food" flowers. Their active ingredients, pharmacological activities, and treatments for related diseases are reviewed, and the limitations and development prospects of the "homology of medicine and food" flowers are discussed. It is hoped that this will contribute to the development of the food and pharmacological fields.

Osmanthus Fragrans Loaded NIPAAM Hydrogel Promotes Osteogenic Differentiation of MC3T3-E1

There is an urgent need to find long-acting, natural osteogenesis-promoting drug systems. In this study, first the potential targets and mechanism of osmanthus fragrans (O. fragrans) extract in regulating osteogenic differentiation based on autophagy were analyzed by network pharmacology and molecular docking. Then, osmanthus fragrans was extracted using the ethanol reflux method and an osmanthus fragrans extract loaded Poly N-isopropylacrylamide (OF/NIPAAM) hydrogel was prepared by electron beam radiation. The chemical components of the osmanthus fragrans extract and the microstructure of OF/NIPAAM hydrogels were characterized by ultraviolet-visible spectrophotometry (UV-Vis) and X-ray diffraction (XRD), respectively. Mouse embryonic osteoblast precursor cells MC3T3-E1 were cultured with different concentrations of OF/NIPAAM hydrogel to discover cell proliferation activity by CCK-8 assay. Alkaline phosphatase (ALP) staining and alizarin red staining were used to observe the differentiation and calcification. Through experimental exploration, we found that a total of 11 targets were predicted, which are TP53, CASP3, SIRT1, etc., and osmanthus fragrans had good binding activity to TP53. In vitro, except for proliferation promotion, OF/NIPAAM hydrogel enhanced ALP activity and formation of mineralized nodules of MC3T3-E1 cells at a concentration equal to or less than 62.5 μg/mL (p < 0.05). The addition of autophagy inhibitor 3-methyladenine (3-MA) reduced ALP activity and mineralized nodule formation.

Traditional uses, phytochemical constituents and pharmacological properties of Osmanthus fragrans: A review

ETHNOPHARMACOLOGICAL RELEVANCE

Osmanthus fragrans Lour., is a medicinal plant distributed widely in some Asian countries including Japan and Korea and southwestern China. It has been used traditionally for the treatment of weakened vision, halitosis, panting, asthma, cough, toothache, stomachache, diarrhea, rheumatism, physique pain and hepatitis.

AIM OF THE REVIEW

Recent advances in traditional uses, botanical characteristics, distribution, taxonomy, phytochemical constituents, biological effects as well as the toxicities of O. fragrans are comprehensively presented and critically evaluated, and the underlying mechanism associated with the bioactivities of extracts, essential oil and components from this plant is also well summarized. In order to provide comprehensive scientific basis for the medical application and help interested researchers discover food and medicinal natural products from O. fragrans.

MATERIALS AND METHODS

All information was systematically gathered from globally accepted scientific databases by Internet databases, including Elsevier, ScienceDirect, PubMed, Web of Science, Wiley, Springer, SciFinder, ACS Publications, CNKI, WanFang, Google Scholar, Baidu Scholar, The Plant List Database, and other literature sources (Ph.D. and MSc dissertations). All published contributions on O. fragrans different languages were included and cited. The chemical structures of all isolated compounds were drawn by using ChemBioDraw Ultra 14.0 software.

RESULTS

To date, more than 183 compounds were isolated and structurally identified from different plant parts of O. fragrans. Among them, ionone, ionol, flavonoids, polyphenols and iridoids, as the major bioactive substances, have been extensively studied and displayed the best bioactivity. Pharmacological studies demonstrated that O. fragrans and its active components had a wide range of biological activities, such as antioxidant, antitumor, anti-inflammatory, anti-hyperglycemic, anti-thrombotic, anti-melanogenesis, neuroprotective, and hepatoprotective activities, etc. CONCLUSION: O. fragrans, as a food and medicinal resource, has a good health care function and important edible and medicinal value, and thus has good prospects for utilization. However, many studies on biological activities were mainly based on extracts and the bioactive ingredients of this plant, and the mechanism responsible for these extracts and ingredients have not been well identified and there is a gap in research regarding clinical effect and safety. Therefore, the detail in vitro and in vivo studies on the mechanisms of action of the pure bioactive compounds and more clinical studies are encouraged to be conducted to ensure safety and effectiveness of the plant for human use.

Exploration of Osmanthus fragrans Lour.'s composition, nutraceutical functions and applications

Osmanthus fragrans (Thunb.) Lour. has been cultivated in China for over 2500 years. Due to the unique and strong fragrance, O. fragrans flowers have long been added into food, tea, and beverages. Not only the O. fragrans flowers, but also leaves, barks, roots, and fruits possess some beneficial effects such as relieving pain and alleviating cough in Traditional Chinese Medicine. Modern pharmacological researches demonstrated that O. fragrans possesses a broad spectrum of biological activities including antioxidant, neuroprotective, antidiabetic and anticancer activities etc. A large number of phytochemicals identified in O. fragrans are responsible for its health promoting and disease preventing effects. The components of volatile compounds in O. fragrans are complex but the content is less abundant. The present review mainly focuses on the bioactive ingredients identified from O. fragrans, the therapeutic effects of O. fragrans and its applications in food, cosmetics and medicines.

Insights Into the MYB-Related Transcription Factors Involved in Regulating Floral Aroma Synthesis in Sweet Osmanthus

As an important member of the MYB transcription factor (TF) family, the MYB-related TFs play multiple roles in regulating the synthesis of secondary metabolites and developmental processes, as well as in response to numerous biotic and abiotic stressors in plants. However, little is known regarding their roles in regulating the formation of floral volatile organic compounds (VOCs). In this study, we conducted a genome-wide analysis of MYB-related proteins in sweet osmanthus; 212 OfMYB-related TFs were divided into three distinct subgroups based on the phylogenetic analysis. Additionally, we found that the expansion of the OfMYB-related genes occurred primarily through segmental duplication events, and purifying selection occurred in all duplicated gene pairs. RNA-seq data revealed that the OfMYB-related genes were widely expressed in different organs of sweet osmanthus, and some showed flower organ/development stage-preferential expression patterns. Here, three OfMYB-related genes (OfMYB1R70/114/201), which were expressed nuclearly in floral organs, were found to be significantly involved in regulating the synthesis of floral VOCs. Only, OfMYB1R201 had transcriptional activity, thus implying that this gene participates in regulating the expression of VOC synthesis related genes. Remarkably, the transient expression results suggested that OfMYB1R70, OfMYB1R114, and OfMYB1R201 are involved in the regulation of VOC synthesis; OfMYB1R114 and OfMYB1R70 are involved in accelerating β-ionone formation. In contrast, OfMYB1R201 decreases the synthesis of β-ionone. Our results deepen our knowledge of the functions of MYB-related TFs and provide critical candidate genes for the floral aroma breeding of sweet osmanthus in the future.

Microencapsulation of Osmanthus essential oil by interfacial polymerization: Optimization, characterization, release kinetics, and storage stability of essential oil from microcapsules

In this paper, the interface polymerization method was used to prepare Osmanthus essential oil microcapsules. The optimal preparation process of Osmanthus essential oil microcapsules was explored as follows: the dosage ratio of Osmanthus essential oil to N100 was 6:1, the reaction temperature was 70°C, and the reaction time was 2 h. The encapsulation efficiency of Osmanthus essential oil microcapsules could reach 80.31%. The particle size distribution, morphology, chemical structure, and thermal stability of the obtained microcapsules were characterized by laser particle size analyzer, scanning electron microscopy, Fourier transform infrared spectroscopy, and thermogravimetric analysis. The release kinetics and storage stability experiments of the microcapsules were studied. The results showed that the average volume diameter of the microcapsules was 101.2 µm. The microcapsules were in the shape of full spheres, with a smooth surface, low viscosity, and high elasticity. Microencapsulation improved the thermal stability of Osmanthus essential oil and promoted the slow release of essential oil. The synthesized microcapsules showed good storage stability under refrigerated and dark conditions, which indicated that microcapsules had broad application prospects in food, medicine, and other fields. PRACTICAL APPLICATION: In this study, we prepared a polyurea membrane to encapsulate Osmanthus essential oil microcapsules by interfacial polymerization. The encapsulation conditions of the microcapsules were optimized and the structure of the microcapsules was characterized in this study. The results showed that microcapsules had a full spherical shape with a smooth surface, high elasticity, good sustained-release ability, good thermal stability, and storage stability. These properties indicated that microcapsules have good application prospects and can be used as a high-quality flavor with a long residual effect and high thermal stability for food and cosmetic scope.

Antioxidant and anticancer potentials of edible flowers: where do we stand?

Edible flowers are attracting special therapeutic attention and their administration is on the rise. Edible flowers play pivotal modulatory roles on oxidative stress and related interconnected apoptotic/inflammatory pathways toward the treatment of cancer. In this review, we highlighted the phytochemical content and therapeutic applications of edible flowers, as well as their modulatory potential on the oxidative stress pathways and apoptotic/inflammatory mediators, resulting in anticancer effects. Edible flowers are promising sources of phytochemicals (e.g., phenolic compounds, carotenoids, terpenoids) with several therapeutic effects. They possess anti-inflammatory, anti-diabetic, anti-microbial, anti-depressant, anxiolytic, anti-obesity, cardioprotective, and neuroprotective effects. Edible flowers potentially modulate oxidative stress by targeting erythroid nuclear transcription factor-2/extracellular signal-regulated kinase/mitogen-activated protein kinase (Nrf2/ERK/MAPK), reactive oxygen species (ROS), nitric oxide (NO), malondialdehyde (MDA) and antioxidant response elements (AREs). As the interconnected pathways to oxidative stress, inflammatory mediators, including tumor necrosis factor (TNF)-α, nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), interleukins (ILs) as well as apoptotic pathways such as Bcl-2-associated X protein (Bax), Bcl-2, caspase and cytochrome C are critical targets of edible flowers in combating cancer. In this regard, edible flowers could play promising anticancer effects by targeting oxidative stress and downstream dysregulated pathways.

HPLC Analysis and Antioxidant Evaluation of Acteoside-Rich Osmanthus fragrans Extracts

A method for the separation and quantification of acteoside by reverse-phase high-performance liquid chromatography (HPLC) was developed and validated. Hot water and ethanolic extracts of Osmanthus fragrans leaves and flowers were analyzed for acteoside content. Excellent linearity was obtained, with an r2 higher than 0.999. The precision, specificity, and accuracy of our method were excellent, suggesting that it can be conveniently used for the quantification of acteoside in the crude extract of O. fragrans. The hot water and ethanol extracts were analyzed, and their biological activities were tested. The extraction yields, marker (acteoside) contents, and antioxidant activities of the leaf and flower extracts were analyzed. The antioxidant activity was confirmed by measuring the 2,2-diphenyl-2-picrylhydrazyl radical scavenging activity, reducing power, and total phenolic content. The acteoside content tended to be higher in the 100% ethanol extract of O. fragrans compared to those with the other extraction conditions tested. Overall, almost all extracts prepared with ethanolic solvents tended to produce better antioxidant activity than those prepared with hot water. These results suggest that the ethanolic extract of O. fragrans could serve as a potential antioxidant and anti-inflammatory pharmaceutical source, and our validated method would be useful for the quality control of O. fragrans extracts.

Genome-Wide Identification, Classification, and Expression Profiling Reveals R2R3-MYB Transcription Factors Related to Monoterpenoid Biosynthesis in Osmanthus fragrans

Osmanthus fragrans is widely grown for the purpose of urban greening and the pleasant aroma emitted from its flowers. The floral scent is determined by several monoterpenoid volatiles, such as linalool and its oxides, which are a few of the most common volatiles and the main components of the essential oils in most sweet osmanthus cultivars. In addition, the relative contents of cis- and trans-linalool oxide (furan) may affect the aromas and quality of the essential oils. MYB proteins represent the largest family of transcription factors in plants and participate in regulating secondary metabolites. Several cis-elements, especially AC-rich regions, are known to be bound by 2R-MYBs and could be found in the promoter of the enzyme genes in the terpenoid metabolic pathway. However, there has to date been no investigation into the 2R-MYB family genes involved in regulating terpenoid biosynthesis in O. fragrans. Here, 243 non-redundant 2R-MYB proteins were grouped into 33 clusters based on the phylogeny and exon-intron distribution. These genes were unevenly distributed on 23 chromosomes. Ka/Ks analysis showed that the major mode of 2R-MYB gene evolution was purifying selection. Expression analysis indicated that 2R-MYB genes in O. fragrans exhibited varied expression patterns. A total of 35 OfMYBs representing the highest per kilobase per million mapped reads in the flower were selected for quantitative real-time PCR analysis. The correlation analysis between the expression level and the contents of fragrant compounds at different flowering stages suggested that OfMYB19/20 exhibited remarkably positive correlation with the accumulation of cis-linalool oxides. OfMYB51/65/88/121/137/144 showed significantly negative correlations with one or more linalool oxides. Characterization of these proteins revealed that OfMYB19 and OfMYB137 were localized in the nuclei, but did not show transcriptional activation in the yeast system, which suggested that they may be bound to other transcription factors to exert regulatory functions. These findings provide useful information for further functional investigation of the 2R-MYBs and offer a foundation for clarifying the 2R-MYB transcription factors involved in the molecular mechanism of the regulation of monoterpenoid biosynthesis in Osmanthus fragrans.

Antipyretic, anti-inflammatory and analgesic activities of Periplaneta americana extract and underlying mechanisms

Periplaneta americana is a common traditional Chinese medicinal material which has been used to treat arthritis, fever, aches, pains, and inflammation of the extremities for several hundred years. However, little scientific data exists in literature to support its use. The purpose of this study was to evaluate the antipyretic, anti-inflammatory and analgesic activities of Periplaneta americana extract (PAE) and explore its underlying mechanism. The antipyretic, anti-inflammatory and analgesic activities were evaluated by LPS-induced fever, carrageenan-induced paw edema, abdominal writhing, hot plate and formalin tests, respectively. The mechanism of action was explored by antioxidant activity analysis, inflammatory cytokines expression and febrile mediator measurement, and pathway activation analysis. The results from UHPLC-HRMS indicated that the extract was found to contain dopamine, coumarin, dipeptide, vitamin, organic acid, amino acid and its metabolites, and other organic compounds. PAE showed in a dose-dependent manner antioxidant activity and reduced the protein production and mRNA expression of NO, IL-1β, IL-6, and TNF-α in RAW 264.7 cells in vitro. Moreover, PAE significantly and dose-dependently inhibited the writhing responses and licking time in formalin tests, increased response latency in the hot plate test, reduced carrageenan-induced paw edema and inflammation in mice, decreased LPS-induced rT increase in rats. Furthermore, PAE treatment markedly inhibited the increase in the levels of NO, IL-6, IL-1β, TNF-α, PGE₂ and cAMP in plasma of fevered rat, greatly suppressed the activation of inflammatory response pathway and the change of MDA and GSH concentration, MPO and SOD activity as well as FRAP capacity in paw induced by carrageenan injection. In conclusion, the findings suggested that PAE produced potential antinociceptive, anti-inflammatory and antipyretic effects by reducing production of endogenous inflammatory mediators and blocking the MAPK/NF-κB signaling pathway which support the claim for its traditional use in the treatment of various diseases.

A rapid, accurate and sensitive method for determination of monosaccharides in different varieties of Osmanthus fragrans Lour by pre-column derivatization with HPLC-MS/MS

A specific HPLC-MS/MS (High-Performance Liquid Chromatography with tandem Mass Spectrometry) method was developed and validated for simultaneous determination of several monosaccharides in three kinds Osmanthus fragrans Lour. After extraction, separation, protein removal, pigment removal and hydrolysis, monosaccharides was finally obtained from Osmanthus fragrans Lour. Positive ion mode detection and Multiple Reaction Monitoring (MRM) mode were used for quantitative analysis by PMP pre-column derivatization and Electrospray Ionization (ESI). Analysis and content determination of 6 monosaccharide components in 3 kinds of Osmanthus fragrans Lour. The HPLC separation was achieved on a Shim-pack VP-ODS6022748 (150 L × 2.0) with gradient elution at a flow rate of 0.2 ml/min in a run time of 40 min, and the mobile phase was acetonitrile-5 mmol/L ammonium acetate. PMP derivatization in HPLC-MS/MS can accurately measure Osmanthus fragrans Lour. mannose (Man), ribose (Rib), rhamnose (Rha), galacturonic acid (Gal UA), glucose (Glu), galactose (Gal), xylose (Xyl), fucose (Fuc). The results showed that HPLC-MS/MS pre-column derivatization method was simple and rapid, with small measurement error, but high sensitivity and good repeatability. The analysis of monosaccharide components in polysaccharide components has important practical significance.

Polyphenols in the prevention and treatment of periodontal disease: A systematic review of in vivo, ex vivo and in vitro studies

Plant-derived polyphenols with antimicrobial and immunomodulatory characteristics appear to provide a variety of oral health benefits. Thus, the aim of the present study was to review the scientific literature to identify these effects of polyphenols on periodontal pathogens and inflammation. A MEDLINE search from 1st January 2013 to 18th January 2018 was performed to identify studies reporting polyphenol-containing plant extracts. Reports regarding pure compounds and essential oils, as well as effects on bacteria that are not defined as periodontal pathogens, were excluded. Thirty-eight studies matched the selection criteria. Studies on immunomodulatory effects included in vitro, ex vivo, and in vivo studies (n = 23), whereas studies reporting antibacterial effects against periodontal pathogens included only in vitro studies (n = 18). Three studies were included in both groups. The antibacterial effects were characterised by inhibition of bacterial growth, adhesion to oral cells, and enzymatic activity. Decreased secretion of pro-inflammatory and increased secretion of anti-inflammatory cytokines were demonstrated. Higher attachment levels, lower inflammation, and bone loss were reported by in vivo studies. Due to the high heterogeneity, it is difficult to draw clear conclusions for applicability; nevertheless, polyphenols have great potential as antimicrobial and immunomodulatory substances in the treatment and prevention of periodontal disease.

Transcriptomic Analysis of the Candidate Genes Related to Aroma Formation in Osmanthus fragrans

Osmanthus fragrans, or “RiXiangGui”, is an ornamental, woody, evergreen plant that is cultivated widely because it blooms recurrently and emits a strong fragrance. Recently, the germplasm resources, classification, and aroma compositions of O. fragrans have been investigated. However, the molecular mechanisms of the floral scent formation and regulation have remained largely unknown. To obtain a global perspective on the molecular mechanism of the aroma formation during blooming, nine RNA Sequencing (RNA-Seq) libraries were constructed from three flowering stages: The initial, full, and final flowering stage. In short, a total of 523,961,310 high-quality clean reads were assembled into 136,611unigenes, with an average sequence length of 792 bp. About 47.43% of the unigenes (64,795) could be annotated in the NCBI non-redundant protein database. A number of candidate genes were identified in the terpenoid metabolic pathways and 1327 transcription factors (TFs), which showed differential expression patterns among the floral scent formation stages, were also identified, especially OfMYB1, OfMYB6, OfWRKY1, and OfWRKY3, which could play critical roles in the floral scent formation. These results indicated that the floral scent formation of O. fragrans was a very complex process which involved a large number of TFs. This study provides reliable resources for further studies of the O.fragrans floral scent formation.

Antilipotoxicity Activity of Osmanthus fragrans and Chrysanthemum morifolium Flower Extracts in Hepatocytes and Renal Glomerular Mesangial Cells

The excess influx of free fatty acids (FFAs) into nonadipose tissues, such as those of liver and kidney, induces lipotoxicity leading to hepatic steatosis and renal dysfunction. The aim of this study was to investigate the protective effects of methanolic flower extracts of Osmanthus fragrans (OF) and Chrysanthemum morifolium (CM) against FFA-induced lipotoxicity in hepatocytes (human HepG2 cells) and renal glomerular mesangial cells (mouse SV40-Mes13 cells). The results showed that OF and CM significantly suppressed FFA-induced intracellular triacylglycerol accumulation via partially inhibiting the gene expression of sterol regulatory element-binding protein-1c (SREBP-1c) and glycerol-3-phosphate acyltransferase (GPAT) in HepG2 cells. Both extracts inhibited reactive oxygen species (ROS) generation by FFA-stimulated HepG2 cells. OF and CM also suppressed the mRNA expression of interleukin- (IL-) 1β, IL-6, IL-8, tumor necrosis factor- (TNF-) α, and transforming growth factor- (TGF-) β by HepG2 cells treated with conditioned medium derived from lipopolysaccharide-treated THP-1 monocytes. Furthermore, OF and CM effectively inhibited oleate-induced cellular lipid accumulation, TGF-β secretion, and overexpression of fibronectin in mesangial cells. In conclusion, OF and CM possess hepatoprotective activity by inhibiting hepatic fat load and inflammation and renal protection by preventing FFA-induced mesangial extracellular matrix formation.

Degradation of phenylethanoid glycosides in Osmanthus fragrans Lour. flowers and its effect on anti-hypoxia activity

This study was aimed at investigating the chemical stability (the thermal, light and pH stability) of phenylethanoid glycosides (PhGs) in Osmanthus fragrans Lour. flowers, identifying the degradation products of acteoside and salidroside (major PhGs in O. fragrans flowers) by UPLC–QTOF–MS and studying the anti-hypoxia activity of PhGs after degradation. The degradation of PhGs followed first-order reaction kinetics, and the rate constant of acteoside (4.3 to 203.4 × 10⁻³ day⁻¹) was higher than that of salidroside (3.9 to 33.3 × 10⁻³ day⁻¹) in O. fragrans flowers. Salidroside was mainly hydrolyzed to tyrosol during storage, and the degradation products of acteoside were verbasoside, caffeic acid, isoacteoside, etc. In a model of cobalt chloride (CoCl₂)-induced hypoxia in PC12 cells, the anti-hypoxia ability of PhGs decreased after degradation, which resulted from the reduction of PhGs contents. Particularly, caffeic acid exhibited stronger anti-hypoxia ability than acteoside and could slightly increase the anti-hypoxia ability of degraded acteoside. The results revealed that high temperature, high pH and light exposure caused PhGs degradation, and thus the anti-hypoxia ability of PhGs reduced.

Origin Discrimination of Osmanthus fragrans var. thunbergii Flowers using GC-MS and UPLC-PDA Combined with Multivariable Analysis Methods

INTRODUCTION

Osmanthus fragrans flowers are used as folk medicine and additives for teas, beverages and foods. The metabolites of O. fragrans flowers from different geographical origins were inconsistent in some extent. Chromatography and mass spectrometry combined with multivariable analysis methods provides an approach for discriminating the origin of O. fragrans flowers.

OBJECTIVE

To discriminate the Osmanthus fragrans var. thunbergii flowers from different origins with the identified metabolites.

METHODS

GC-MS and UPLC-PDA were conducted to analyse the metabolites in O. fragrans var. thunbergii flowers (in total 150 samples). Principal component analysis (PCA), soft independent modelling of class analogy analysis (SIMCA) and random forest (RF) analysis were applied to group the GC-MS and UPLC-PDA data.

RESULTS

GC-MS identified 32 compounds common to all samples while UPLC-PDA/QTOF-MS identified 16 common compounds. PCA of the UPLC-PDA data generated a better clustering than PCA of the GC-MS data. Ten metabolites (six from GC-MS and four from UPLC-PDA) were selected as effective compounds for discrimination by PCA loadings. SIMCA and RF analysis were used to build classification models, and the RF model, based on the four effective compounds (caffeic acid derivative, acteoside, ligustroside and compound 15), yielded better results with the classification rate of 100% in the calibration set and 97.8% in the prediction set.

CONCLUSIONS

GC-MS and UPLC-PDA combined with multivariable analysis methods can discriminate the origin of Osmanthus fragrans var. thunbergii flowers. Copyright © 2017 John Wiley & Sons, Ltd.