Osmanthus Fragrans Flowers Research Articles

Acteoside palliates d-galactose induced cognitive impairment by regulating intestinal homeostasis.

Acteoside, an important phenylethanol glycoside, is the main active component in Osmanthus fragrans flower. Our previous study found that acteoside showed high antiaging effect but its absorption rate was low. We speculated acteoside palliated aging-related cognitive impairment before being absorbed, that was intestinal homeostasis underlie the antiaging effect of acteoside. In this study, acteoside was confirmed to palliate cognitive impairment in d-galactose induced aging mice. Acteoside treatment dramatically reduced oxidative stress, alleviated intestinal inflammation, restored intestinal mucosal barrier, rebuilt gut microbiome structure and upregulated gut microbiome metabolites short-chain fatty acids (SCFAs) and amino acids (AAs). Furthermore, antibiotic treatment revealed that the antiaging ability of acteoside was abolished in microbiota depleted mice, which offered direct evidence for the essential role of gut microbiota in the attenuation of cognitive impairment of acteoside. Together, our study indicated that acteoside palliated cognitive impairment by regulating intestinal homeostasisand acteoside intake might be a promising nutritional intervention in prevention of neurodegenerative diseases.

Insights into the Cytochrome P450 Monooxygenase Superfamily in Osmanthus fragrans and the Role of OfCYP142 in Linalool Synthesis.

Osmanthus fragrans flowers have long been used as raw materials in food, tea, beverage, and perfume industries due to their attractive and strong fragrance. The P450 superfamily proteins have been reported to widely participate in the synthesis of plant floral volatile organic compounds (VOCs). To investigate the potential functions of P450 superfamily proteins in the fragrance synthesis of O. fragrans, we investigated the P450 superfamily genome wide. A total of 276 P450 genes were identified belonging to 40 families. The RNA-seq data suggested that many OfCYP genes were preferentially expressed in the flower or other organs, and some were also induced by multiple abiotic stresses. The expression patterns of seven flower-preferentially expressed OfCYPs during the five different flower aroma content stages were further explored using quantitative real-time PCR, showing that the CYP94C subfamily member OfCYP142 had the highest positive correlation with linalool synthesis gene OfTPS2. The transient expression of OfCYP142 in O. fragrans petals suggested that OfCYP142 can increase the content of linalool, an important VOC of the O. fragrans floral aroma, and a similar result was also obtained in flowers of OfCYP142 transgenic tobacco. Combined with RNA-seq data of the transiently transformed O. fragrans petals, we found that the biosynthesis pathway of secondary metabolites was significantly enriched, and many 2-C-methyl-D-erythritol 4-phosphate (MEP) pathway genes were also upregulated. This evidence indicated that the OfCYP proteins may play critical roles in the flower development and abiotic response of O. fragrans, and that OfCYP142 can participate in linalool synthesis. This study provides valuable information about the functions of P450 genes and a valuable guide for studying further functions of OfCYPs in promoting fragrance biosynthesis of ornamental plants.

Identification of Antioxidant Components and Tyrosinase Specific Inhibitors from Osmanthus fragrans Flower by Using Online UPLC-ABTS+·-assay and UF- LC-MS Technology

Identification of Antioxidant Components and Tyrosinase Specific Inhibitors from Osmanthus fragrans Flower by Using Online UPLC-ABTS+·-assay and UF- LC-MS Technology

Chemical fingerprinting, quantification, and antioxidant activity evaluation of Osmanthus fragrans (Thunb.) Lour. Flowers by UPLC-ECD

ABSTRACT Osmanthus fragrans (Thunb.) Lour. flowers are important natural resource of phenolic compounds, which have antioxidant activities and have been consumed as functional food and dietary supplements for thousand years. Ultra-performance liquid chromatography coupled with electrochemical detection (UPLC-ECD) was developed to simultaneously analyze the eight phenolic compounds in Osmanthus fragrans flowers collected from different regions across China. The UPLC-ECD fingerprint was established for identification and comprehensive quality control. The antioxidant capacities of Osmanthus fragrans flowers were evaluated, and results were compared with those spectrophotometric antioxidant methods. A highly positive relationship was confirmed between the total peak area of characteristic components in chromatogram and the antioxidant potential determined by spectrophotometry with correlation coefficient greater than 0.80 (p < .01). Grey relational analysis showed that acteoside had the highest degree of correlation with antioxidant capacity. These results provided evidence to support the use of UPLC-ECD as a simple, rapid, and reliable method for electroactive phenolic component determination and antioxidant capacity quantification in vitro system.

Acteoside, the Main Bioactive Compound in Osmanthus fragrans Flowers, Palliates Experimental Colitis in Mice by Regulating the Gut Microbiota.

The present study investigated the effects of Osmanthus fragrans flowers and acteoside on murine colitis and the underlying mechanisms. The O. fragrans flower extract (OFE) and acteoside were administrated to chemically induced colitic mice. The results showed that OFE or acteoside ameliorates intestinal inflammation, oxidative stress, and activation of nuclear factor-κB (NF-κB) in colitic mice. The dysbiosis of the gut microbiome in colitic mice was also partly restored by OFE or acteoside, which was characterized by the alteration of the gut microbiome structure and the enrichment of beneficial bacteria (Akkermansia muciniphila and Bacteroides thetaiotaomicron). Dextran sulfate sodium (DSS)-induced gut metabolome dysfunctions (e.g., sphingosine metabolism and amino acids metabolism) in colitic mice were also partly restored by OFE and acteoside. A fecal microbiota (FM) transplantation study suggested that, compared with the FM from the normal diet-dosed donor mice, the FM from the OFE- or acteoside-dosed donor mice significantly suppressed colitic symptoms.

Microwave-assisted green extraction of antioxidant components from Osmanthus fragrans (Lour) flower using natural deep eutectic solvents

Osmanthus fragrans (Lour) flower is a typical fragrant herb in eastern countries containing multiple bioactive compounds, the extract of which has been widely used as a natural antioxidant additive in food and cosmetics. However, the existing extraction methods use organic solvents during the extraction process, which is non-eco-friendly and harmful to human health. In this study, we introduce, to our knowledge for the first time, microwave-assisted deep eutectic solvent extraction (MA-DESE) to extract antioxidant components from O. fragrans flower. The MA-DESE procedure was optimised, validated, and compared with that of traditional solvent extraction by using response surface methodology. The maximum antioxidant activity of 101.81 mg Trolox equivalent/g of dry weight was achieved at the following optimum MA-DESE parameters: microwave power, 497.12 W; microwave treatment time, 59.03 s; and solid–liquid ratio, 31.14 mL/g. In addition, UPLC-MS analysis showed a greater variety of antioxidant components, such as olivil and osmanthuside H, in O. fragrans flower extract obtained by MA-DESE than by the traditional ethanol reflux method. These results demonstrated that MA-DESE, which is safe and eco-friendly, could substitute for the conventional solvent extraction process, which is time-consuming and tedious, for the extraction of antioxidant components from O. fragrans flower.

Sweet Olive Extract Attenuates Dextran Sulfate Sodium-Induced Colitis in Mice.

Sweet olive (Osmanthus fragrans flowers) is used to treat dysentery and reduce phlegm and stasis in traditional Chinese medicine. Recently, we found that verbascoside, the major component in the sweet olive ethanolic extract (OFE), inhibited IL-8 secretion in human colorectal adenocarcinoma WiDr cells. However, evidence-based treatment of inflammatory bowel disease (IBD) with the extract is yet to be performed. To evaluate the therapeutic effect of OFE, we measured IL-8 suppression by OFE and verbascoside in a WiDr cell culture assay. In the IL-8 secretion assay, both OFE (100 μg/mL) and verbascoside (10 μM) significantly inhibited IL-8 production in WiDr cells. Furthermore, we designed cotreated (dextran sulfate sodium [DSS]+OFE-treated) and post-treated (DSS-OFE-treated) protocols to access the therapeutic effects of OFE in vivo. Mice treated with 500 mg/kg per day OFE exhibited significant improvement in IBD symptoms, including disease activity index score, body weight, and colon length maintenance. The suppressive effects on myeloperoxidase expression and lower histopathology scores (including neutrophil infiltration) for the colon were also found. These findings suggest that OFE exerts anti-inflammatory effect on DSS-induced colitis.

Osmanthus fragrans Flower Aqueous Extract and its Enriched Acteoside inhibit Melanogenesis and Ultraviolet-induced Pigmentation

The Osmanthus fragrans flower (OFF) is commonly used as an additive for tea in China and as a traditional medicine to treat dysentery, asthma and hepatitis. In the current study, we have acquired the aqueous extract of the dried OFF (OFFE) and determined its enriched acteoside contents. However, whether OFFE and acteoside can modulate melanogenesis and pigmentation has yet to be determined. We here provide novel data revealing that OFFE and acteoside inhibit melanogenesis induced by α-MSH in B16 melanoma cells via the MITF-tyrosinase signaling pathway. Treatment with α-MSH (1μM) enhanced melanin levels and tyrosinase activity, up-regulated the mRNA levels of MITF and tyrosinase and increased the dendritic number in B16 melanoma cells, effects all being intervened by OFFE and acteoside. Of interest, OFFE and acteoside showed no direct inhibition of tyrosinase activity as revealed by our ex vivo tyrosinase activity assay. In addition, OFFE produced a depigmenting action on UVB-induced hyperpigmentation in guinea pigs, as shown by the improved skin brightness and the decreased melanin staining. Our data have demonstrated that OFFE can alter melanogenesis via modulating the MITF-tyrosinase signaling thereby leading to its depigmenting action in the in vivo model. OFFE could be a substitute for acteoside as a promising skin-whitening agent.

Sequential Combination of Microwave- and Ultrasound-Assisted Extraction of Total Flavonoids from Osmanthus fragrans Lour. Flowers.

Microwave-assisted and ultrasound-assisted extraction assays were used to isolate total flavonoids (TF) from Osmanthus fragrans flowers. The effects of the solid-liquid ratio, ethanol concentration, microwave power, microwave extraction time, ultrasonic power and ultrasonic extraction time on the yield of TF were studied. A sequential combination of microwave- and ultrasound-assisted extraction (SC-MUAE) methods was developed, which was subsequently optimized by Box-Behnken design-response surface methodology (BBD-RSM). The interaction effects of the ethanol concentration (40–60%), microwave extraction time (5–7 min), ultrasonic extraction time (8–12 min) and ultrasonic power (210–430 W) on the yield of TF were investigated. The optimum operating parameters for the extraction of TF were determined to be as follows: ethanol concentration (48.15%), microwave extraction time (6.43 min), ultrasonic extraction time (10.09 min) and ultrasonic power (370.9 W). Under these conditions, the extraction yield of TF was 7.86 mg/g.

Analysis of the main active ingredients and bioactivities of essential oil from Osmanthus fragrans Var. thunbergii using a complex network approach

BackgroundOsmanthus fragrans has been used as folk medicine for thousands of years. The extracts of Osmanthus fragrans flowers were reported to have various bioactivities including free radical scavenging, anti-inflammation, neuroprotection and antitumor effects. However, there is still lack of knowledge about its essential oil.MethodsIn this work, we analyzed the chemical composition of the essential oil from Osmanthus fragrans var. thunbergii by GC-MS. A complex network approach was applied to investigate the interrelationships between the ingredients, target proteins, and related pathways for the essential oil. Statistical characteristics of the networks were further studied to explore the main active ingredients and potential bioactivities of O. fragrans var. thunbergii essential oil.ResultsA total of 44 ingredients were selected from the chemical composition of O. fragrans var. thunbergii essential oil, and that 191 potential target proteins together with 70 pathways were collected for these compounds. An ingredient-target-pathway network was constructed based on these data and showed scale-free property as well as power-law degree distribution. Eugenol and geraniol were screened as main active ingredients with much higher degree values. Potential neuroprotective and anti-tumor effect of the essential oil were also found. A core subnetwork was extracted from the ingredient-target-pathway network, and indicated that eugenol and geraniol contributed most to the neuroprotection of this essential oil. Furthermore, a pathway-based protein association network was built and exhibited small-world property. MAPK1 and MAPK3 were considered as key proteins with highest scores of centrality indices, which might play an important role in the anti-tumor effect of the essential oil.ConclusionsThis work predicted the main active ingredients and bioactivities of O. fragrans var. thunbergii essential oil, which would benefit the development and utilization of Osmanthus fragrans flowers. The application of complex network theory was proved to be effective in bioactivities studies of essential oil. Moreover, it provides a novel strategy for exploring the molecular mechanisms of traditional medicines.

Antioxidant synergistic effects of Osmanthus fragrans flowers with green tea and their major contributed antioxidant compounds

The antioxidant synergistic effects of Osmanthus fragrans flowers with green tea were evaluated, and their major antioxidant compounds contributed to the total amount of synergy were determined. The antioxidant compounds in O. fragrans flowers with green tea were identified by LC-MS and quantified by UPLC-PDA. The synergistic antioxidant interactions between O. fragrans flowers with green tea and their antioxidant compounds were tested using the Prieto’s model after the simulated digestion. The main antioxidant compounds in O. fragrans flowers were acteoside and salideroside, whereas the main antioxidant compounds in green tea were caffeine, gallic acid, and L-epicatechin. The significant synergistic effect between O. fragrans flowers and green tea was observed and among nearly all of the combinations of their antioxidant compounds. Among the combinations, acteoside and gallic acid contributed most to the antioxidant synergy between O. fragrans flowers and green tea. However, the simulated digestion decreased this antioxidant synergy because it reduced the contents and the antioxidant capacities of their compounds, as well as the antioxidant synergy among the compounds.

Inhibitory Potential of Constituents from Osmanthus fragrans and Structural Analogues Against Advanced Glycation End Products, \u03b1-Amylase, \u03b1-Glucosidase, and Oxidative Stress

Inhibition of α-amylase and α-glucosidase, advanced glycation end products (AGEs) formation, and oxidative stress by isolated active constituents of Osmanthus fragrans flowers (9,12-octadecadienoic acid and 4-(2,6,6-trimethyl-1-cyclohexenyl)-3-buten-2-one) and their structural analogues were evaluated. 9,12-Octadecadienoic acid was 10.02 and 22.21 times more active against α-amylase and α-glucosidase, respectively, than acarbose and ascorbic acid, followed by 9,12,15-octadecatrienoic acid, 9-octadecenoic acid, 4-(2,6,6-trimethyl-1-cyclohexenyl)-3-buten-2-one, 4-(2,6,6-trimethyl-2-cyclohexenyl)-3-buten-2-one, 1-heptadecanecarboxylic acid, and 1-pentadecanecarboxylic acid. Concerning the inhibition of AGEs formation, similar with data for 2,2’-diphenyl-1-picrylhydrazl radical scavenging activities, 9,12-octadecadienoic acid was 3.54 times more active than aminoguanidine, followed by 9,12,15-octadecatrienoic acid, and 9-octadecenoic acid. These results indicate that 4-(2,6,6-trimethyl-1-cyclohexenyl)-3-buten-2-one, 9,12-octadecadienoic acid and their analogues inhibit α-amylase and α-glucosidase, AGEs formation, and oxidative stress have potential value in alleviating diabetic pathological conditions.

Biotransformation of Volatiles in Fermented Osmanthus (Osmanthus fragrans) Flowers by Yeast

Sweet osmanthus (Osmanthus fragrans) is a species of flowering plants in Asia prized for food, flavor and fragrance industries. This work studied biotransformation of volatiles in osmanthus flowers through monoculture fermentation of infusions of sweet osmanthus flowers using yeasts, Saccharomyces cerevisiae and Williopsis saturnus. The major volatiles in two osmanthus cultivars Jingui and Yingui before and after fermentation were terpenoids and ketones. Esters, alcohols and acetic acid were only present after fermentation, and aldehydes were largely depleted after fermentation. The volatile profile of sweet osmanthus flowers fermented with S. cerevisiae was described as sweet and floral, while that of sweet osmanthus flowers fermented with W. saturnus was fruity, sweet and floral. Addition of nutrients (glucose and diammonium phosphate) increased alcohol and ester production, decreased percentage reduction of ketones and terpenes. Biotransformation of terpenes varied with each compound and fermentation treatment. Overall, yeast fermentation proved to be effective in enhancing sweet osmanthus flower fragrance for production of unique essential oils from this invaluable flower.

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

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

Volatile Components of Crude Extracts of Osmanthus fragrans Flowers and Their Antibacterial and Antifungal Activities

Volatile Components of Crude Extracts of Osmanthus fragrans Flowers and Their Antibacterial and Antifungal Activities

Varietal classification and antioxidant activity prediction of Osmanthus fragrans Lour. flowers using UPLC–PDA/QTOF–MS and multivariable analysis

This study was aimed to classify the varieties and predict the antioxidant activity of Osmanthus fragrans flowers by UPLC–PDA/QTOF–MS and multivariable analysis. The PLS–DA model successfully classified the four varieties based on both the 21 identified compounds and the effective compounds. For the antioxidant activity prediction, PLS performed well to predict the antioxidant activity of O. fragrans flowers. Furthermore, acteoside, suspensaside A, ligustroside, forsythoside A, phillygenin and caffeic acid were selected as effective compounds by UVE–SPA for prediction. On the basis of effective compounds, PLS, MLR and PCR were applied to establish the calibration models. The UVE–SPA–MLR model was the optimal method to predict the antioxidant activity values with Rp of 0.9200, 0.9010 and 0.8905 for DPPH, ABTS and FRAP assays, respectively. The results revealed that the UPLC–PDA/QTOF–MS combined with chemometrics could be a new method to classify the varieties and predict the antioxidant activity of O. fragrans flowers.

Optimization of Ultrasound-Assisted Extraction of Natural Antioxidants from the Osmanthus fragrans Flower.

An ultrasound-assisted extraction (UAE) method was developed to extract natural antioxidants from the Osmanthus fragrans flower. The effect of UAE on antioxidant activity of the extract from the Osmanthus fragrans flower was studied using a Trolox equivalent antioxidant capacity (TEAC) assay. Optimization conditions were firstly determined using a single-factor experiment, and response surface methodology was then used to evaluate interaction of several experimental parameters. Analysis of the coefficient of determination showed that second-order polynomial models produced a highly satisfactory fitting of the experimental data with regard to TEAC values (R2 = 0.9829, p < 0.0001). The optimal conditions were 39.1% ethanol, and extraction for 35.2 min at 59.4 °C. Under these conditions, the maximum TEAC value was 584.9 ± 6.0 μmol Trolox/g DW, which was higher than those obtained by the conventional extracting method (486.4 ± 12.6 μmol Trolox/g DW) and the Soxhlet extraction method (339.1 ± 16.2 μmol Trolox/g DW). The crude extract obtained could be used either as a food additive or in pharmaceuticals for the prevention and treatment of diseases caused by oxidative stress.

The safety of Osmanthus fragrans ethanol extract treatment in BALB/c mice

Background: Osmanthus fragrans flower, recently certificated as a new natural antioxidant, has been used in various foods. We per- formed an acute and subacute toxicological test for evaluating the safety and toxicity of 75 % ethanol extraction of Osmanthus fragrans (OFEE). Method: In the acute toxicity study, a single dose of 5 g/kg and 10 g/kg of the extract was administered orally to six mice. General be- haviour, mortality and toxic symptoms were determined daily for 14 days. For the subacute toxicity, two groups of 12 mice received 0.9% normal saline (control) and 1 g/kg of the extract daily for 28 consecutive days by oral gavage. The animals were observed daily for abnormal clinical signs and death. Body weight, haematological and biochemical parameters of blood as well as kidney, liver, lung and spleen tissues histology were evaluated. Results: The total phenolic contents in OFEE were 371.71 ± 12.35 mg GAE/g extracts and total flavonoid contents were 47.23 ± 5.36 mg QE/g extract. OFEE did not cause any mortality or morbidity. Maximum tolerated dose (MTD) was 10 g/kg body weight in our BALB/c mice, which can be regarded as virtually non-toxic. Administration of OFEE at dose 1 g/kg/day for 28-day did not cause changed in hematological, biochemical assay, and histopathological conditions change, suggesting a no-observed-adverse-effect level (NOVEL) of 1 g/kg/day. Conclusion: We found no evidence of adverse effects in our laboratory test and pathological studies. 75 % ethanol extraction may safely be used in the research of Osmanthus fragrans in animal and probably human studies.

The Ethanol Extract of Osmanthus fragrans Flowers Reduces Oxidative Stress and Allergic Airway Inflammation in an Animal Model.

The Osmanthus fragrans flower, a popular herb in Eastern countries, contains several antioxidant compounds. Ben Cao Gang Mu, traditional Chinese medical literature, describes the usefulness of these flowers for phlegm and stasis reduction, arrest of dysentery with blood in the bowel, and stomachache and diarrhea treatment. However, modern evidence regarding the therapeutic efficacy of these flowers is limited. This study was aimed at assessing the antioxidative effects of the ethanol extract of O. fragrans flowers (OFE) in vivo and evaluating its antioxidant maintenance and therapeutic effect on an allergic airway inflammation in mice. After OFE's oral administration to mice, the values obtained in the oxygen radical absorbance capacity assay as well as the glutathione concentration in the lungs and spleens of mice increased while thiobarbituric acid reactive substances decreased significantly, indicating OFE's significant in vivo antioxidant activity. OFE was also therapeutically efficacious in a mouse model of ovalbumin-induced allergic airway inflammation. Orally administered OFE suppressed ovalbumin-specific IgE production and inflammatory cell infiltration in the lung. Moreover, the antioxidative state of the mice improved. Thus, our findings confirm the ability of the O. fragrans flowers to reduce phlegm and suggest that OFE may be useful as an antiallergic agent.