Rosa canina extract relieves methylation alterations of pancreatic genes in STZ-induced diabetic rats : Gene methylation in diabetic rats treated with an extract.

BACKGROUND: Diabetes is a chronic metabolic disease that affects many parts of the body. Considering diabetes as a beta cells' defect and loss, the focus is on finding mechanisms and compounds involved in stimulating the function and regeneration of pancreatic ß-cells. DNA methylation as an epigenetic mechanism plays a pivotal role in the ß-cells' function and development. Considering the regenerative and anti-diabetic effects of Rosa canina extract, this study aimed to assess the methylation levels of Pdx-1, Pax-4, and Ins-1 genes in diabetic rats treated with Rosa Canina extract. METHODS AND RESULTS: Streptozotocin-induced diabetic rats were used to evaluate the frequency of Pdx-1, Pax-4, and Ins-1 gene methylation. Treatment groups were exposed to Rosa canina as spray-dried and decoction extracts. Following blood glucose measurement, pancreatic DNA was extracted and bisulfited. Genes' methylation was measured using MSP-PCR and qRT-PCR techniques. Oral administration of Rosa canina extracts significantly reduced blood sugar levels in diabetic rats compared to the control group. The methylation levels of the Pdx-1, Pax-4, and Ins-1 genes promoter in streptozotocin-induced diabetic rats increased compared to the control rats while, the treatment of diabetic rats with Rosa canina extracts, spray-dried samples especially, led to a decreased methylation in these genes. CONCLUSION: The results of this study showed that Rosa canina extract as a spray-dried sample could be effective in treating diabetes by regulating the methylation of genes including Pdx-1, Pax-4, and Ins-1 involved in the activity and regeneration of pancreatic islet cells.

Flower Power: An Overview on Chemistry and Biological Impact of Selected Essential Oils from Blossoms.

Natural raw materials such as essential oils have received more and more attention in recent decades, whether in the food industry, as flavorings and preservatives, or as insecticides and insect repellents. They are, furthermore, very popular as fragrances in perfumes, cosmetics, and household products. In addition, aromatherapy is widely used to complement conventional medicine. This review summarizes investigations on the chemical composition and the most important biological impacts of essential oils and volatile compounds extracted from selected aromatic blossoms, including Lavandula angustifolia, Matricaria recutita, Rosa x damascena, Jasminum grandiflorum, Citrus x aurantium, Cananga odorata, and Michelia alba. The literature was collected from PubMed, Google Scholar, and Science Direct. Blossom essential oils discussed in this work are used in a wide variety of clinical issues. The application is consistently described as safe in studies and meta-analyses, although there are notes that using essential oils can also have side effects, especially dermatologically. However, it can be considered as confirmed that essential oils have positive influences on humans and can improve quality of life in patients with psychiatric disorders, critically ill patients, and patients in other exceptional situations. Although the positive effect of essential oils from blossoms has repeatedly been reported, evidence-based clinical investigations are still underrepresented, and the need for research is demanded.

In vitro efficacy of Rosa damascena solid state fermentation liquid and water extract on skin care.

BACKGROUND: As a medicinal and food homologous plant, Rosa damascena is not only highly ornamental, but also rich in a variety of active ingredients such as polyphenols and flavonoids. It is widely used in cosmetics, food and pharmaceutical industries. OBJECTIVE: To study the in vitro efficacy of Rosa damascena solid state fermentation liquid (RDF) and water extract (RDE). METHODS: Firstly, the effect of RDF and RDE on the proliferation rate of B16F10 cells was detected by CCK-8 method, and the melanin content was measured by sodium hydroxide lysis method to evaluate the whitening effect of them. Finally, the antioxidant, anti-wrinkling and soothing effects of RDF and RDE were evaluated by biochemical methods in vitro. RESULTS: RDF and RDE within a certain concentration range (0.05%-0.5%) had no effect on the proliferation of B16F10 cells. Compared with Rosa damascena extract (RDE), RDF showed significant effects on bleaching, antioxidant, anti-wrinkling and soothing, among which 0.5% RDF showed the best effect. CONCLUSION: Both RDF and RDE at a certain concentration have effect on skin care in vitro, but the effect of RDF is more significant than that of RDE.

Biosensor-based active ingredient recognition system for screening potential small molecular Severe acute respiratory syndrome coronavirus 2 entry blockers targeting the spike protein from Rugosa rose.

The traditional formulation Hanchuan zupa granules (HCZPs) have been widely used for controlling coronavirus disease 2019 (COVID-19). However, its active components remain unknown. Here, HCZP components targeting the spike receptor-binding domain (S-RBD) of SARS-CoV-2 were investigated using a surface plasmon resonance (SPR) biosensor-based active ingredient recognition system (SPR-AIRS). Recombinant S-RBD proteins were immobilized on the SPR chip by amine coupling for the prescreening of nine HCZP medicinal herbs. Ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) identified gallic acid (GA) and methyl gallate (MG) from Rosa rugosa as S-RBD ligands, with KD values of 2.69 and 0.95 µM, respectively, as shown by SPR. Molecular dynamics indicated that GA formed hydrogen bonds with G496, N501, and Y505 of S-RBD, and MG with G496 and Y505, inhibiting S-RBD binding to angiotensin-converting enzyme 2 (ACE2). SPR-based competition analysis verified that both compounds blocked S-RBD and ACE2 binding, and SPR demonstrated that GA and MG bound to ACE2 (KD = 5.10 and 4.05 µM, respectively), suggesting that they blocked the receptor and neutralized SARS-CoV-2. Infection with SARS-CoV-2 pseudovirus showed that GA and MG suppressed viral entry into 293T-ACE2 cells. These S-RBD inhibitors have potential for drug design, while the findings provide a reference on HCZP composition and its use for treating COVID-19.

Rosa laevigata Polysaccharides Ameliorate Dextran Sulfate Sodium-Induced Ulcerative Colitis of Beagles through Regulating Gut Microbiota.

Rosa laevigata Michx. polysaccharides (RLP) have been demonstrated to possess antioxidant and anti-inflammatory properties. However, the mechanisms and efficacy of these polysaccharide components in preventing ulcerative colitis (UC) remain to be elucidated. The efficacy and mechanisms of RLP were investigated in a study that utilized healthy adult beagles to establish a UC model, considering the similarities in gut microbiota between humans and dogs. In the study, the beagle model induced by sodium dextran sulfate exhibited typical symptoms of ulcerative colitis, such as weight loss and diarrhea. All these symptoms and changes were significantly ameliorated through oral supplementation of RLP. Additionally, microbial community analysis based on the 16S rDNA gene revealed that RLP alleviated UC by increasing the abundance of beneficial bacteria and reducing the abundance of harmful bacteria. In conclusion, our study has provided that RLP effectively alleviated colitis by preserving the intestinal barrier and regulating the gut microbiota composition.

Investigation of Rosa species by an optimized LC-QTOF-MS/MS method using targeted and non-targeted screening strategies combined with multivariate chemometrics.

INTRODUCTION: Plants of the Rosa genus are renowned for their pronounced and pleasant aroma and colors. OBJECTIVE: The aim of this work was to develop a novel liquid chromatographic triple quadrupole time-of-flight tandem mass spectrometric (LC-QTOF-MS/MS) method for the investigation of the bioactive fingerprint of petals of different genotypes belonging to Rosa damascena and Rosa centifolia species. METHODOLOGY: Central composite design (CCD) of response surface methodology (RSM) was used for the optimization of the LC-QTOF-MS/MS method. The method was validated and target, suspect, and non-target screening workflows were applied. Statistical analysis and chemometric tools were utilized to explore the metabolic fingerprint of the Rosa species. RESULTS: RSM revealed that the optimal extraction parameters involved mixing 11 mg of sample with 1 mL of MeOH:H2O (70:30, v/v). Target analysis confirmed the presence of 11 analytes, all of which demonstrated low limits of quantification (LOQs; as low as 0.048 ng mg-1) and sufficient recoveries (RE: 85%-107%). In total, 28 compounds were tentatively identified through suspect analysis. Non-target analysis enabled the generation of robust OPLS-DA and HCA models that classified the samples according to their species with 100% accuracy. CONCLUSIONS: A novel LC-QTOF-MS/MS method was developed and applied in the analysis of 47 R. centifolia and R. damascena flowers belonging to different genotypes.

Structural Characterization and In Vitro Anti-Inflammatory Activity of Polysaccharides Isolated from the Fruits of Rosa laevigata.

RLPa-2 (Mw 15.6 kDa) is a polysaccharide isolated from Rosa laevigata Michx. It consists of arabinose (Ara), galactose (Gal), rhamnose (Rha), glucose (Glc), xylose (Xyl), and galacturonic acid (Gal-UA) with a molar ratio of 1.00:0.91:0.39:0.34:0.25:0.20. Structural characterization was performed by methylation and NMR analysis, which indicated that RLPa-2 might comprise →6)-α-D-Galp-(1→, →4)-α-D-GalpA-(1→, α-L-Araf-(1→, →2,4)-α-D-Glcp-(1→, ß-D-Xylp, and α-L-Rhap. In addition, the bioactivity of RLPa-2 was assessed through an in vitro macrophage polarization assay. Compared to positive controls, there was a significant decrease in the expression of M1 macrophage markers (CD80, CD86) and p-STAT3/STAT3 protein. Additionally, there was a down-regulation in the production of pro-inflammatory mediators (NO, IL-6, TNF-α), indicating that M1 macrophage polarization induced with lipopolysaccharide (LPS) and interferon-γ (IFN-γ) stimulation could be inhibited by RLPa-2. These findings demonstrate that the RLPa-2 might be considered as a potential anti-inflammatory drug to reduce inflammation.

Therapeutic Potential of Rosa davurica Pall. Root Extract as an Antidiabetic Agent: A Comprehensive Analysis from Molecular Mechanisms to In Vivo Efficacy.

Rosa davurica Pall. is widely used in traditional oriental herbal therapy, but its components and molecular mechanisms of action remain unclear. This study investigates the antidiabetic potential of Rosa davurica Pall. root extract (RDR) and elucidates its underlying molecular mechanisms with in vitro and in vivo models. Data from the current study show that RDR exhibits strong antioxidant activity and glucose homeostasis regulatory effects. It significantly impacts glucose homeostasis in C2C12 skeletal muscle cells by inhibiting α-glucosidase activity. Further molecular mechanistic studies revealed that RDR promoted glucose uptake by phosphorylation of AMP-activated protein kinase (AMPK)/acetyl-CoA carboxylase (ACC), but not Phosphatidylinositol 3-kinase (PI 3-kinase)/Akt in C2C12 skeletal muscle cells. These actions increased the expression and translocation of glucose transporter type 4 (GLUT4) to the plasma membrane. In addition, RDR treatment in the STZ-induced diabetic rats remarkably improved the low body weight, polydipsia, polyphagia, hyperglycemia, and islet architecture and increased the insulin/glucose ratio. The liver (ALT and AST) and kidney marker enzyme (BUN and creatinine) levels were restored by RDR treatment as well. Phytochemical analysis identified eight major constituents in RDR, crucial for its antioxidant and antidiabetic activity. Through the molecular docking of representative glucose transporter GLUT4 with these compounds, it was confirmed that the components of RDR had a significantly high binding score in terms of structural binding. These findings from the current study highlight the antidiabetic effects of RDR. Collectively, our data suggest that RDR might be a potential pharmaceutical natural product for diabetic patients.

Influence of Three Modification Methods on the Structure, Physicochemical, and Functional Properties of Insoluble Dietary Fiber from Rosa roxburghii Tratt Pomace.

Rosa roxburghii Tratt pomace is rich in insoluble dietary fiber (IDF). This study aimed to investigate the influence of three modification methods on Rosa roxburghii Tratt pomace insoluble dietary fiber (RIDF). The three modified RIDFs, named U-RIDF, C-RIDF, and UC-RIDF, were prepared using ultrasound, cellulase, and a combination of ultrasound and cellulase methods, respectively. The structure, physicochemical characteristics, and functional properties of the raw RIDF and modified RIDF were comparatively analyzed. The results showed that all three modification methods, especially the ultrasound-cellulase combination treatment, increased the soluble dietary fiber (SDF) content of RIDF, while also causing a transition in surface morphology from smooth and dense to wrinkled and loose structures. Compared with the raw RIDF, the modified RIDF, particularly UC-RIDF, displayed significantly improved water-holding capacity (WHC), oil-binding capacity (OHC), and swelling capacity (SC), with increases of 12.0%, 84.7%, and 91.3%, respectively. Additionally, UC-RIDF demonstrated the highest nitrite ion adsorption capacity (NIAC), cholesterol adsorption capacity (CAC), and bile salt adsorption capacity (BSAC). In summary, the combination of ultrasound and cellulase treatment proved to be an efficient approach for modifying IDF from RRTP, with the potential for developing a functional food ingredient.

Optimization of total flavonoids purification process in rose by uniform design method.

This study aims to establish a method for purifying total flavonoids in roses using macroporous resin columns, intending to leverage and harness their potential. We screened six macroporous resins to evaluate their capacity for their adsorption and desorption, ultimately identifying X5 macroporous resin as the most effective. To comprehensively understand the adsorption behavior, we analyzed it using various models, such as pseudo-first-order and pseudo-second-order kinetic models, particle diffusion models, and Langmuir, Freundlich, and Temkin isotherm models. Employing both single-factor and uniform design, approaches, the focus of this work was on maximizing the total flavonoid recovery rate. A 3-factor and 10-level uniform design table was utilized for optimizing the optimal process parameters and exploring the antioxidant properties of the purified flavonoids. The optimal process conditions for purifying total flavonoids from roses can be summarized as follows: a sample concentration of 2 mg/mL, pH at 2, 55 mL sample volume, eluent ethanol concentration of 75%, eluent volume of 5 BV, and the elution rate set at 1 mL/min. Following purification, the total flavonoid content peaked at 57.82%, achieving an 84.93% recovery rate, signifying substantial antioxidant potential. Consequently, the method established for purifying TFR using X5 macroporous resin in this study proves to be a dependable and reliable method consistent approach.

Phytochemical Profile and Bioactivity of Bound Polyphenols Released from Rosa roxburghii Fruit Pomace Dietary Fiber by Solid-State Fermentation with Aspergillus niger.

This study aimed to investigate the phytochemical profile, bioactivity, and release mechanism of bound polyphenols (BPs) released from Rosa roxburghii fruit pomace insoluble dietary fiber (RPDF) through solid-state fermentation (SSF) with Aspergillus niger. The results indicated that the amount of BPs released from RPDF through SSF was 17.22 mg GAE/g DW, which was significantly higher than that achieved through alkaline hydrolysis extraction (5.33 mg GAE/g DW). The BPs released through SSF exhibited superior antioxidant and α-glucosidase inhibitory activities compared to that released through alkaline hydrolysis. Chemical composition analysis revealed that SSF released several main compounds, including ellagic acid, epigallocatechin, p-hydroxybenzoic acid, quercetin, and 3,4-dihydroxyphenylpropionic acid. Mechanism analysis indicated that the disruption of tight structure, chemical bonds, and hemicellulose was crucial for the release of BPs from RPDF. This study provides valuable information on the potential application of SSF for the efficient release of BPs from RPDF, contributing to the utilization of RPDF as a functional food ingredient.

Stability of Bioactive Compounds and Antioxidant Activity in Rosehip Juice (Rosa spp.).

Rosehip fruits, characterized by their high concentrations of bioactive compounds and antioxidant activity (AA), have been traditionally used to make jams, infusions, and juices. Thus, the objective of this research was to evaluate the stability of rosehip juice by determining the concentrations of bioactive compounds and total phenols and the AA using chromatographic and spectroscopic methods. The stability of the juice was evaluated with three treatments and different storage conditions, namely, unpasteurized-refrigerated, pasteurized-room temperature, and pasteurized-refrigerated, and measurements were taken for eight months. Individual and total phenolic compounds, evaluated by chromatographic methods, reported differences until the end of this study. The total phenolic compounds by Folin-Ciocalteu method presented an average decrease of 57% in the three treatments in relation to the initial conditions. On the other hand, the ascorbic acid content decreased considerably, disappearing at week six. Furthermore, for the unpasteurized-refrigerated and pasteurized-refrigerated samples, a correlation was found between flavonols, total phenols, ascorbic acid, and antioxidant activity determined by the TEAC method. For the pasteurized-room temperature samples, correlations were found between the levels of several flavonols, hydroxycinnamic acid, total phenols, and ascorbic acid and the antioxidant activity determined by the CUPRAC method. The stability of the compounds was mainly correlated with the storage conditions of the juice and not with pasteurization. The highest stability was observed for the unpasteurized-refrigerated and pasteurized-refrigerated samples. Although the concentrations of the compounds evaluated decreased during this study, significant levels of AA persisted, providing beneficial characteristics for consumer health.

Micronized Rose Petal Powder: A Valuable Edible Floral Food Ingredient Containing Bioactive Compounds.

Flower petals, as byproducts, provide significant health benefits and can be used in food production. In this study, the impact of the micronization process using a ball mill on the properties of micronized powders derived from wild rose petals of the rugosa variety (Rosa rugosa Thunb.) was examined. The micronized rose powders were subjected to an investigation regarding their particle size, color, molecular characterization (FTIR), electronic nose procedure and antioxidant potential. The study found that micronization considerably reduced d50 particle dimensions from 98.6 µm to 39.9 µm. An FTIR analysis revealed the presence of characteristic (2980, 1340, and 1225 cm-1) bands. The hydrolysable tannins are the most abundant polyphenolic chemicals in rose powders, followed by anthocyanins. Rose powders are an extremely valuable antioxidant raw material due to their high total phenol content (71.8 mg GAE/g), which increased by approximately 26% after micronization. The antioxidant activity, as determined by ABTS•+, DPPH• and FRAP, is likewise very high. The intensity of volatile chemicals decreased in powders after micronization.

Molecular and Phytochemical Characteristics of Flower Color and Scent Compounds in Dog Rose (Rosa canina L.).

This study delves into the chemical and genetic determinants of petal color and fragrance in Rosa canina L., a wild rose species prized for its pharmacological and cosmetic uses. Comparative analysis of white and dark pink R. canina flowers revealed that the former harbors significantly higher levels of total phenolics (TPC) and flavonoids (TFC), while the latter is distinguished by elevated total anthocyanins (TAC). Essential oils in the petals were predominantly composed of aliphatic hydrocarbons, with phenolic content chiefly constituted by flavonols and anthocyanins. Notably, gene expression analysis showed an upregulation in most genes associated with petal color and scent biosynthesis in white buds compared to dark pink open flowers. However, anthocyanin synthase (ANS) and its regulatory gene RhMYB1 exhibited comparable expression levels across both flower hues. LC-MS profiling identified Rutin, kaempferol, quercetin, and their derivatives as key flavonoid constituents, alongside cyanidin and delphinidin as the primary anthocyanin compounds. The findings suggest a potential feedback inhibition of anthocyanin biosynthesis in white flowers. These insights pave the way for the targeted enhancement of R. canina floral traits through metabolic and genetic engineering strategies.

Comparative metabolomic analysis reveals nutritional properties and pigmentation mechanism of tea-scented rosehips.

BACKGROUND: The fruits of the genus Rosa, commonly known as rosehips, have attracted significant attention owing to their rich content of various bioactive compounds. However, their utility is generally secondary to the ornamental appeal of their flowers. This study aimed to explore the quality differences among tea-scented rosehips found in Yunnan, China, including those of Rosa odorata var. odorata (RO), Rosa odorata var. gigantea (RG), and Rosa yangii (RY). Morphological characteristics, chemical composition, and antioxidant activity of their fruits were evaluated. RESULTS: The study revealed significant variability in composition and biological activities based on fruit color. RO exhibited the highest levels of polyphenols, flavonoids, anthocyanins, carotenoids, and vitamin C, with the strongest antioxidant activity (10.99 µmol Trolox·g-1 ), followed by RG (7.91 µmol Trolox·g-1 ) and RY (6.52 µmol Trolox·g-1 ). This supports RO's potential as a functional food source. Untargeted metabolomics identified and quantified 502 metabolites, with flavonoids (171) and phenolic acids (147) as the main metabolites. The differential metabolites among the fruits are primarily enriched for flavonoid biosynthesis and phenylpropanoid biosynthesis pathways. Insights into color formation supported the role of anthocyanins, flavones, and flavonols in fruit color variation. CONCLUSION: Tea-scented rosehips offer vibrant colors and high nutritional value with potent biological activities. Rosa odorata var. odorata stands out as a functional food source owing to its rich bioactive compounds. These findings lay the groundwork for utilizing rosehips in functional foods, health supplements, and food additives, emphasizing the practical and beneficial applications of Rosa spp. independent of their ornamental value. © 2023 Society of Chemical Industry.

Protective effect of soluble dietary fiber from Rosa roxburghii Tratt residue on dextran sulfate sodium-induced ulcerative colitis by regulating serum metabolism and NF-κB pathway in mice.

BACKGROUND: Ulcerative colitis (UC) refers to an idiopathic chronic inflammatory bowel disease that starts with inflammation of the intestinal mucosa. Dietary fiber plays a crucial role in maintaining the normal architecture of the intestinal mucosa. In this study, the protective effect and potential mechanism of soluble dietary fiber from Rosa roxburghii Tratt residue (SDFR) on dextran sulfate sodium (DSS)-induced UC mice were explored. RESULTS: The results revealed that SDFR could ameliorate body weight loss and pathological injury, improve the structure and crypt destruction in colon in DSS-induced mice. Moreover, the levels of NO, IL-1ß, TNF-α, MPO and protein expression of iNOS and COX-2 were decreased after administration of SDFR. Notably, nontargeted metabolomics analysis indicated that there were significant differences in 51 potential metabolites in serum between the DSS and control groups. SDFR intervention could regulate aberrant alterations of these metabolites and mitigate UC via regulating metabolic pathways, including arachidonic acid and glycerophospholipid metabolism. CONCLUSION: This study provides novel evidence that SDFR could be used as a potential modulator to relieve UC. Also, the results provide a theoretical basis for the utilization of byproducts in Rosa roxburghii Tratt fruit processing. © 2024 Society of Chemical Industry.

Rosa roxburghii tratt residue: A novel feed resource for cattle indicated by the non-deleterious performance and blood metabolites.

Rosa roxburghii tratt residue (RRTR) is a regional and uncommon byproduct in Guizhou. Little information is available on whether RRTR can be used as feed for ruminants. In this study, the feasibility of using RRTR as a new feed resource for cattle was investigated by chemical composition analysis, in vitro gas production (Trial 1) and animal feeding experiments (Trial 2). In trial 1, compared to the commonly used fruit residues, RRTR had a proximate nutrient level; the in vitro gas production curve and dynamics fell within the normal range. In trial 2, 16 cattle were allocated to the control and treatment groups, with 8 replicates of 1 cattle each. Cattle in the control group were fed a basal diet without RRTR, while those in the treatment group were fed a diet containing 30% RRTR to replace 30% whole corn silage in basal diet. Feeding RRTR had little effect on the growth performance of the control and treatment cattle (P > 0.05). The feed-to-gain ratio was greater in the treatment group than in the control group throughout the trial period (P < 0.05). The plasma urea levels in the treatment group were lower (P < 0.05) than that in control group, and the levels of other plasma biochemical metabolites were not different between the two groups of cattle (P > 0.05). The in vivo rumen fermentation parameters did not differ between the control and treatment groups (P > 0.05). Our findings indicate that RRTR has a nutritional profile (crude protein, neutral detergent fiber, acid detergent fiber, and crude fiber) similar to that of commonly used fruit residues (such as apple, pineapple, and citrus residue et al.); improves plasma protein utilization efficiency; and has no negative impact on growth performance, albeit with limited effects on feed conversion; blood metabolites, and rumen fermentation parameters in cattle. Accordingly, we conclude, based on the above-mentioned result, that RRTR can serve as a novel feed alternative resource when considering the affordability and as a practical choice for low-cost diets for cattle.

High-resolution monophenolase/diphenolase/radical scavenging profiling for rapid screening of natural whitening candidates from Rosa rugosa cv. 'Plena'.

Antioxidants and tyrosinase inhibitory components were successfully screened and separated from Rosa rugosa cv. 'Plena' by high-performance liquid chromatography microfractionation bioactive screening combined with several separation and purification methods. Ethyl acetate extract of Rosa rugosa cv. 'Plena' showed high antioxidant activity and tyrosinase inhibitory activity. High-speed countercurrent chromatography, silica gel column chromatography, and semi-preparative high-performance liquid chromatography were used for the preparative separation of four bioactive components from ethyl acetate extract. Two tyrosinase-inhibiting active substances, flavogallonic acid, and N1 -N5 -N10 -tri-4-p-coumaroylspermidine, were isolated from Rosa rugosa cv. 'Plena', and they showed great monophenolase inhibition activity (half-maximal inhibitory concentration: 664.60 and 23.77 µg/ml, respectively) and excellent diphenolase inhibition activity (half-maximal inhibitory concentration: 23 614.61 and 16.80 µg/ml, respectively). Meanwhile, gallic acid, flavogallonic acid, and ellagic acid were shown to have excellent 1,1-diphenyl-2-picryl-hydrazyl antioxidant activity (half maximal inhibitory concentration: 6.66, 20.17, and 13.45 µg/ml), and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) antioxidant activity (half maximal inhibitory concentration: 3.53, 3.83, and 2.78 µg/ml). Molecular docking revealed that flavogallonic acid and N1 -N5 -N10 -tri-4-p-coumaroylspermidine had a strong binding affinity (-9.3 and -10 kcal/mol, respectively) to tyrosinase through hydrogen bonding and hydrophobic interactions.

Antibacterial Pattern of Rosa roxburghii Tratt Pomace Crude Extract Against Staphylococcus aureus and Its Application in Preservation of Cooked Beef.

Staphylococcus aureus is a common foodborne pathogen and spoilage bacterium in meat products. To develop a natural preservative for meat products, this study revealed the antibacterial activity and mechanism of Rosa roxburghii Tratt pomace crude extract (RRPCE) against S. aureus, and applied RRPCE to the preservation of cooked beef. The diameter of inhibition zone, minimum inhibitory concentration (MIC), and minimum bactericide concentration of RRPCE against S. aureus were 15.85 ± 0.35 to 16.21 ± 0.29 mm, 1.5 mg/mL, and 3 mg/mL, respectively. The growth curve of S. aureus was completely stalled by treatment with RRPCE at 2 MIC. RRPCE results in the decrease of intracellular adenosine 5'-triphosphate (ATP) content, depolarization of cell membrane, leakage of cell fluid including nucleic acid and protein, and destruction of cell membrane integrity and cell morphology. During storage, RRPCE significantly reduced S. aureus viable counts, pH, and total volatile basic nitrogen of cooked beef compared with untreated samples (p < 0.05). In addition, RRPCE could significantly increase the redness (a*) value, decrease lightness (L*) and yellowness (b*) values, and slow down the color change of cooked beef (p < 0.05). These findings suggest that RRPCE can effectively inhibit S. aureus, and has the potential as a natural preservative for the preservation of cooked beef.

Comparative Chemical Profiling and Citronellol Enantiomers Distribution of Industrial-Type Rose Oils Produced in China.

The chemical composition and aroma profile of industrial essential oils (EOs) from species of rose grown in China, including the native Kushui rose (R. sertata × R. rugosa) and R. rugosa Thunb. cv. Plena, and the recently introduced Damask rose (R. damascena Mill.), were studied in comparison by means of GC/MS and GC-FID. More than 150 individual compounds were detected in Chinese rose samples, of which 112 were identified and their quantitative content determined, representing 88.7%, 96.7% and 97.9% of the total EO content, respectively. It was found that the main constituents of the Chinese rose EOs were representatives of terpenoid compounds (mono- and sesquiterpenoids, predominantly) and aliphatic hydrocarbons. Comparative chemical profiling revealed different chemical composition and aroma profiles: while the R. damascena oil showed a balance between the eleoptene and stearoptene fractions of the oil (the average ratio between the main terpene alcohols and paraffins was 2.65), in the Kushui and R. rugosa oils, the odorous liquid phase strongly dominated over the stearopten, with a ratio of 16.91 and 41.43, respectively. The most abundant terpene was citronellol, ranging from 36.69% in R. damascena to 48.32% in R. rugosa oil. In addition, the citronellol enantiomers distribution, which is an important marker for rose oil authenticity, was studied for the first time in R. rugosa oil.