Rosa Alba Research Articles

Determination of Phenolic, Flavonoid Content and Antioxidant Activity of Oil Rose Products

Rose and rose products are used as raw materials in many sectors including cosmetics, food and medicine. The Rosa damascena Mill. rose genotype, which is intensively cultivated in the Isparta region of Türkiye, is an important export product. The flower of the plant is main source of raw materials for rose oil, herbal teas and cosmetic products due to its high essential oil and polyphenols contents. In this study, Rosa damascena, Rosa centifolia, Rosa alba L., Rosa alba ‘Semiplena’ genotypes were grown in Yalova, which is an alternative region in terms of agro-climatic conditions from Isparta and its surroundings where rose oil cultivation is carried out in Türkiye. Within the scope of the study, total phenolic matter, total antioxidant activity (DPPH and CUPRAC) and total flavonoid contents of flowers (whole flowers), rose water and wastewater of the genotypes were determined. It is important to identify alternative rose genotypes to R. damascena in Türkiye and their potential for cultivation under different climatic conditions. The highest phenolic content (4115 mg gallic acid equivalent GAE 100 g-1) and DPPH antioxidant activity (4893 mg trolox equivalent TE 100 g-1) values were obtained in R. damascena genotype at the first harvest period. The highest CUPRAC antioxidant activity (34237 mg TE 100 g-1) values were obtained in R. centifolia genotype at the first harvest period. In the second harvest period, the highest phenolic content, DPPH antioxidant activity and CUPRAC antioxidant activity values were determined in R. centifolia genotype. Antioxidant activity, phenolic and flavonoid contents of dried rose flowers were higher than in rose water and wastewater. Rose petals were found to have the potential to be used as an important antioxidant source, while total phenolic matter and antioxidant activity values were found to be low in rose water and wastewater. The harvest period was found to be major factor in oil rose flowers, which can be an important polyphenol source.

Phytochemical Screening, In-silico Toxicity Profiling, and Antidiabetic Potential of the Flowers of Rosa alba L.

Rosa alba L. is a perennial flowering shrub belonging to the Rosaceae family. Diabetes is treated in Assam, India, with a decoction of its flower. But to date, there is no scientific evidence for its antidiabetic potential. Therefore, in addition to toxicity investigations, the current study aimed to determine its antidiabetic potential to support conventional claims. In-silico toxicity profiling for the phytoconstituents of the plant was predicted as non-toxic, non-mutagenic, and non-carcinogenic in mice and rats. The Total phenolic and total flavonoid contents were determined and found to be higher in the ethanolic extract than in the aqueous extract of the flower. Antidiabetic activity of orally administered aqueous and alcoholic extracts (200 mg/kg body weight) was evaluated against the high-fat diet fed with a low dose of streptozotocin-induced diabetic rats. Treatment of these extracts significantly (p<0.001) reduced the blood glucose level and lipid profile in induced-diabetic rats without affecting their liver and kidney functions. It was also shown that the liver and pancreatic tissues of animals treated with extracts had enhanced histopathologic architecture. The findings of the study revealed that the flowers of R. alba are a safe herbal remedy for controlling diabetes.

Physicochemical Characterization of Pectic Polysaccharides from Rose Essential Oil Industry By-Products.

The rose essential oil industry generates large quantities of solid byproducts yearly. These by-products, usually discarded, could yield valuable substances, such as pectic polysaccharides, widely used in the food industry as jelling agents. Seven industrial by-products were investigated as a source of pectic polysaccharides: four samples resulted from the treatment of Rosa damascena, two from Rosa alba, and one from Rosa centifolia. Three by-products were from steam-water distillation, two from CO2-supercritical extraction, and two after extraction with hexane and 1,1,1,2-tetrafluoroethane. The by-products were pretreated with 70% ethanol and extracted with 0.1 M HCl. The highest polysaccharide yield was observed for 1,1,1,2-tetrafluoroethane-extracted (RD_F) Rosa damascena by-products (13.98 ± 0.14%), followed by hexane (RD_X) and CO2-extracted (RD_CO2) Rosa damascena (12.68 ± 0.11 and 12.66 ± 0.10%, respectively). The polysaccharides were middle-methoxylated pectins, except RD_F and RD_X, having 26.68 ± 1.14 and 31.39 ± 1.39 mol % degree of methoxylation (low-methoxyl pectins). The polysaccharides had molecular masses in the 2.3-2.6 × 104 Da range. The rheological studies suggested RD_F formed a strong high-sucrose gel, while the others yielded weak gels. RD_F and RD_X formed strong Ca2+-mediated gels, comparable with commercial low-methoxylated citrus pectin. This study suggests that rose oil industry by-products could be successfully valorized and yield pectic polysaccharides with gelling properties, comparable with commercial citrus pectins.

Postbiotics Production of Candidate-Probiotic Lactiplantibacillus plantarum AC131 with Renewable Bio Resources.

Lactiplantibacillus plantarum is a versatile specie, well known as a producer of lactic acid (LA) and other metabolites with biotechnological significance. The present work characterizes growth and lactic acid production of the candidate-probiotic strain L. plantarum AC131, from Bulgarian white brined cheeses. Different nutritional media with ingredients from renewable resources-reduced sugars from dried distillers' grains with soluble (DDGS) and waste waters from the water-vapor distillation of Bulgarian Rosa alba L. and Rosa damascena Mill. essential oil-were assessed. The results obtained showed significant LA production (up to 95% conversion) in modified MRS broth with reducing sugars from DDGS hydrolysates. The addition of R. alba L. and R. damascena Mill. distillation effluents stimulated the growth and biological activity of postbiotics produced by L. plantarum AC131. In both experimental approaches, a statistically significant inhibition (from 20 to 60%) of E. coli HB 101 growth was found during 24 h exposure and a variable effect on the biofilm formed. In conclusion, reducing sugars from DDGS hydrolysates can be successfully used as a carbon source for lactic acid production. In the case of fermentation without pH control, the process is product inhibited, while with pH control, nearly full conversion was achieved. Postbiotics produced during the process of fermentation showed a variety of biological activity and inhibitory effects on the growth of Escherichia coli HB 101.

Modulation of IL-6 in ameliorating arthritic conditions in rats by Rosa alba L flower extract and fraction

Introduction: rheumatoid arthritis characterized by joint inflammation and pain,affecting millions of peoples around the world. Traditional system of medicine hadproven to be preventive and treating physical and mental illness. Objective: theobjective of the study is to assess anti-arthritic potential of the plant Rosa alba L byconsidering CFA, formaldehyde and turpentine oil induced arthritic model. Materialand Method: ethanolic extract and its ethyl acetate fraction were considered for thestudy and quercetin was quantitatively estimated by high performance thin layer chromatographic(HPTLC) method. Moreover, hematological and biochemical studies(IL-6) were performed in blood and serum of wistar albino rat. Then histopathologicalstudies had also been performed on rat hind paw joint. Result: phytochemicalscreening estimated the presence of carbohydrates, phenolic compounds, flavonoids,phytosterols, amino acids and fixed oil in ethanolic extract and ethyl acetate fraction ofthe plant. Amount of quercetin in the flowers of the plant was found to be 0.26% w/wby quantitative HPTLC method. The level of proinflammatory cytokines, interleukin(IL-6) was considerably decreased (p<0.001) in the fraction treated group of rats at400 mg/kg b.w by considering complete freund’s adjuvant (CFA) induced arthritic model. Conclusion: Ameliorated hematological,hematological, biochemical and histopathologicalparameters confirmed the antiarthritic potential of the plant.

Comparison of in vitro callus induction between Rosa damascena and Rosa alba

Abstract. The potential for callus induction in the local population of Rosa damascena and Rosa alba was studied, and the influence of the different compositions of the main nutrient media and the hormones added to them was established. The results show that the induction and proliferation of callus mass are highly dependent on both the type of nutrient medium and the genotype. The highest total number of responding explants was obtained in Rosa alba, respectively 423 of 720 pre-placed and the highest percentage of explants that formed callus in both genotypes were reported on nutrient medium A24 - from 95% in Rosa damascena to 100% in Rosa alba.

Temperature-dependent Prey Consumption and Functional Response of Episyrphus balteatus De Geer (Diptera: Syrphidae) to Macrosiphum rosae L. (Homoptera: Aphididae) reared on Rosa alba L. under Laboratory Conditions

Laboratory experiments were conducted to determine the prey consumption and functional response of the aphidophagous hoverfly Episyrphus balteatus DeGeer (Diptera: Syrphidae) to different densities of fourth instar rose aphids, Macrosiphum rosae (Homoptera: Aphididae), reared on Rosa alba L. (Rosaceae) at 20 oC, 27 oC and 35 oC. The third instar of E.balteatus consumed a maximum of 51.3±0.53 M. rosae aphids at 27 oC, followed by the third instar with 46.5±0.53 aphid predation at 20 oC. The lowest handling time (Th) was noted for the third instar larvae of E. balteatus (0.407± 0.012) at 27 oC, and the maximum handling time (Th) of (0.662 ± 0.024) was noted for 2nd larvae of E. balteatus at 35 oC. The highest attack rate was noted for 3rd instar larvae (0.201± 0.014) at 27 oC, while the lowest attack rate was noted for second instar at 35 oC. Both instars of Episyrphus balteatus exhibited type II functional response at all three temperatures.

Investigations of Some Morphological, Pomological, and Physiological Parameters with Mineral Content of Different Rosa L. Taxa Grown under Greenhouse Condition

Horticulture is a discipline mainly concerned with the cultivation of plant material for food supply, medicinal use, or functional and aesthetic purposes by humans, they are a genetically diverse group and play an important role in the economy of modern society, as well as at the center of the healthy diet of the urban population. In this respect, Rosa L. are important plants for traditional pharmacological practices and landscape studies. In this context, within the scope of the research, some morphological, pomological, physiological, and mineral contents of important taxa such as Rosa alba L.‘Semiplena’, R. banksiae R.Br. cv ‘Alba’, R. canina L.’Yildiz’, R. centifolia L., R. chinensis Jacq. ‘Old Blush’, R. foetida Herrm., R. heckeliana Tratt. subsp. vanheurckiana (Boiss. Ö. Nilsson), R. hemispharica J.Herrm., R. x odorata (hort ex. Andrews) Sweet ‘Louis XVI’, R. pisiformis (Christ) Sosn., R. x damascena Mill., and R. x damascena Herrm. ‘Semperflorens’(Loisel. & Michel) Rowley for landscape design and horticulture were determined. Within the scope of the research, the morphological, physiological, and pomological characteristics and nutrient contents of taxa adapted to semi-arid conditions and different Rosa taxa spreading in Anatolia were determined. Principal component analysis and cluster analysis were also used to determine the similarities and differences of these parameters measured in different Rosa L. taxa.

Study on Cytotoxic and Genotoxic Potential of Bulgarian Rosa damascena Mill. and Rosa alba L. Hydrosols—In Vivo and In Vitro

The Rosa alba L. and Rosa damascena Mill. growing in Bulgaria are known for their extremely fine essential oil and valuable hydrosols. Irrespectively of its wide use in human life, little research exists on the cytotoxic and genotoxic activity of the hydrosols. This set our goal to conduct cytogenetic analyses to study these effects. A complex of classical cytogenetic methods was applied in three types of experimental test systems—higher plant in vivo, ICR mice in vivo, and human lymphocytes in vitro. Mitotic index, PCE/(PCE + NCE) ratio, and nuclear division index were used as endpoints for cytotoxicity and for genotoxicity—induction of chromosome aberrations and micronuclei. Rose hydrosol treatments range in concentrations from 6% to 20%. It was obtained that both hydrosols did not show considerable cytotoxic and genotoxic effects. These effects depend on the type of the tested rose hydrosols, the concentrations applied in the experiments, and the sensitivity and specificity of the test systems used. Human lymphocytes in vitro were the most sensitive to hydrosols, followed by higher plant and animal cells. Chromosomal aberrations and micronucleus assays suggested that R. damascena and R. alba hydrosols at applied concentrations possess low genotoxic risk. Due to the overall low values in terms of cytotoxic and/or genotoxic effects in all test systems, hydrosols are promising for further use in various areas of human life.

Functional Compounds and Antioxidant Activity of Rosa Species Grown In Turkey

Rose hips differ from other fruits with their high vitamin C, vitamin E, phenolic, and antioxidant content, making it an economical source of antioxidants. Exploring the fruit and seed components of different Rosa species could enable better use of their potential for various industries. Thus, rose hips of Rosa corymbifera, Rosa rugosa (Thunb.), Rosa alba L., and Rosa canina L. cultivated in the same growing conditions were analyzed. Their antioxidant activity and capacity, vitamin C, total carotenoids and phenolics, tocopherols and seed oils, as well as their fatty acid composition were determined. In addition to having highly polyunsaturated fatty acids, R. canina was also found to have noticeably high antioxidant components. In the overall evaluation (both fruit and oil characteristics), R. canina was found to have the most favorable content, while R. rugosa has the most desirable oil characteristics. As a result of the evaluation of fruit (excluding oil), R. corymbifera and R. canina were determined as prominent species. Despite medium level oil content, R. rugosa can be recommended for seed oil uses. R. corymbifera and R. canina are recommended for the food and food supplement industry. Production of rose hip species that contain the remarkable functional components of fruits and the health-promoting fatty acids of seeds may be used in combination as a marketing tool. In this way, the medicinal plant market share and profitability rate of rose hip will increase.

The Anti-Genotoxic Activity of Wastewaters Produced after Water-Steam Distillation of Bulgarian Rosa damascena Mill. and Rosa alba L. Essential Oils.

The steam distillation of valuable rose essential oil from R. damascena Mill. and R. alba L. generates large volumes of wastewaters. Although such wastewaters are bio-pollutants, they contain valuable bioactive compounds. In this study we investigated the cytotoxic/genotoxic and anti-cytotoxic/anti-genotoxic potential of these products. We used cytogenetic methods for induction of chromosome aberrations and micronuclei in two different experimental test-systems: ahigher plant and human lymphocyte cultures. Different experimental schemes of treatment with the waste products showed that the genotoxic activity of wastewater from the distillation of oils from R. alba and R. damascena was low in both test–systems. Human lymphocytes showed a higher sensitivity to the products than plant cells. Both types of waste products manifested anti-genotoxic effect against N-methyl-N′-nitro-N-nitrosoguanidine, a direct mutagen. The wastewaters obtained from steam distillation of rose essential oil have cytoprotective/genoprotective effect and could decrease DNA damage. Data are promising for further use of these products in pharmacy and other areas of human life.

Evaluation of the genotoxic activity of wastewater obtained after steam distillation of essential oil of Bulgarian Rosa alba L. – in vivo study

The process of essential oil water-steam distillation leaves a water fraction as a rest material of the technological process. This residual fraction represents a serious environmental pollutant. The aim of the present study was to investigate the clastogenic and cytotoxic effects of R. alba L. distillation wastewater in laboratory animal's test model in vivo. The ICR mice received a single dose (0.01 mL/b. w.) of 20% (v/v) or 11% (v/v) wastewater solution by intraperitoneal administration. The chromosomal aberrations frequency, mitotic index and micronuclei formation in peripheral blood were scored. The results suggested that the distillation wastewater extracts of white oil-bearing rose R. alba L. did not induce a considerable amount of chromosome aberrations, but a cell proliferation inhibition in mice bone marrow cells, compared to the negative control group (p<0.001). The rodent erythrocyte MN assay showed a slightly increased frequency of micronucleated polychromatic erythrocytes under the present experimental conditions. Rosa alba L. wastewater solution applied showed a negligible genotoxic effect, but a slight antiproliferative effect.

Redox-Modulating Capacity and Antineoplastic Activity of Wastewater Obtained from the Distillation of the Essential Oils of Four Bulgarian Oil-Bearing Roses.

The wastewater from the distillation of rose oils is discharged directly into the soil because it has a limited potential for future applications. The aim of the present study was to determine in vitro the chromatographic profile, redox-modulating capacity, and antineoplastic activity of wastewater obtained by distillation of essential oils from the Bulgarian Rosa alba L., Rosa damascena Mill., Rosa gallica L., and Rosa centifolia L. We applied UHPLC-HRMS for chromatographic analysis of rose wastewaters, studied their metal-chelating and Fe(III)-reducing ability, and performed MTT assay for the evaluation of cytotoxic potential against three tumorigenic (HEPG2—hepatocellular adenocarcinoma, A-375—malignant melanoma, A-431—non-melanoma epidermoid squamous skin carcinoma) and one non-tumorigenic human cell lines (HaCaT—immortalized keratinocytes). The median inhibitory concentrations (IC50) were calculated with nonlinear modeling using the MAPLE® platform. The potential of the wastewaters to induce apoptosis was also examined. Mono-, di-, and acylated glycosides of quercetin and kaempferol, ellagic acid and its derivatives as main chemical components, and gallic acid and its derivatives—such as catechin and epicatechin—were identified. The redox-modulating capacity of the samples (TPTZ test) showed that all four wastewaters exhibited the properties of excellent heavy metal cleaners, but did not exert very strong cytotoxic effects. The lowest IC50 rate was provided in wastewater from R. centifolia (34–35 µg/mL of gallic acid equivalents after a 72 h period for all cell lines). At 24 and 48 hours, the most resistant cell line was HEPG2, followed by HaCaT. After 72 h of exposure, the IC50 values were similar for tumor and normal cells. Still, R. damascena had a selectivity index over 2.0 regarding A-431 non-melanoma skin cancer cells, showing a good toxicological safety profile in addition to moderate activity—IC50 of 35 µg/mL polyphenols. The obtained results related to wastewaters acquired after the distillation of essential oils from the Bulgarian R. alba, R. damascena, R. gallica, and R. centifolia direct our attention to further studies for in-depth elucidation of their application as detoxifying agents under oxidative damage conditions in other experimental datasets.

Subcritical Extracts from Major Species of Oil-Bearing Roses-A Comparative Chemical Profiling.

A comprehensive chemical profiling of 1,1,1,2-tetrafluoroethane (freon R134a) subcritical extracts from the main genotypes of oil-bearing roses, was performed by gas chromatography–mass spectrometry (GC/MS) and gas chromatography with flame ionization detection (GC-FID) in order to reveal the differences in their chemical composition. One hundred and three individual compounds were identified using GC/MS and their quantitative content was determined using GC-FID, representing 89.8, 92.5, 89.7 and 93.7% of the total content of Rosa gallica L., Rosa damascena Mill., Rosa alba L. and Rosa centifolia L. extracts, respectively. The compounds found in the extracts are representatives of the following main chemical classes: mono-, sesqui- and triterpenoids, phenylethanoids and phenylpropanoids and aliphatic hydrocarbons. Fatty acids, esters and waxes were found, as well. The study revealed that 2-phenylethanol is the most abundant component, ranging 9.0–60.9% followed by nonadecane and nonadecene with 5.1–18.0% geraniol (2.9–14.4%), heneicosane (3.1–11.8%), tricosane (0.1–8.6%), nerol (1.3–6.1%) and citronellol (1.7–5.3%). The extracts demonstrate a specific chemical profile, depending on the botanical species—phenylethanoids and phenyl propanoids are the main group for R. damascena, aliphatic hydrocarbons for R. alba and R. centifolia, while both are found in almost equal amounts in R. gallica. The terpenoid compounds show relatively broad variations: monoterpenes—11.9–25.5% with maximum in R. centifolia; sesquiterpenes—0.6–7.0% with maximum in R. gallica and triterpenes—0.4–3.7% with maximum in R. gallica extract.

Antiviral Activity of Rosa damascena Mill. and Rosa alba L. Essential Oils against the Multiplication of Herpes Simplex Virus Type 1 Strains Sensitive and Resistant to Acyclovir.

Simple SummaryHerpes simplex virus type 1 (HSV) is a coated DNA virus of the Herpesviridae family. It causes painful infections of the mouth, throat, face, eyes, central nervous system, as well as infections of the anal–genital area. The specific drugs for chemotherapy of HSV have been based on nucleoside analogues, with acyclovir (ACV) being the most widely used. The most serious problem in the application of nucleoside analogues is the rapid formation of resistant mutants, which also often leads to treatment failure. The search for new therapeutic alternatives for the treatment of HSV is necessary for the successful control of diseases caused by herpes infection. Rose essential oils are widely used in alternative medicine due to their many proven benefits for human health. In the treatment of bacterial and viral infections, they reduce the chance of developing resistance. In this study, we investigated the effects of the Bulgarian Rosa damascena Mill. and Rosa alba L. essential oils on the viral reproduction of susceptible (Victoria strain) and acyclovir-resistant (R-100) strains individually and in combination with acyclovir. When the rose oils were added after the virus entered the cell, co-administered with ACV at a concentration four times lower than the IC50, they contributed to a significant reduction in viral yield by more than 20% of the expected inhibition of viral replication in the Victoria strain and more than 10% of the previously presumptive inhibition in the R-100 strain.Background: The specific chemotherapeutics against herpes simplex virus type 1 (HSV) are nucleoside analogues such as acyclovir (ACV), but the most important problem is the formation of resistant mutants. The search for new therapeutic alternatives leads us to the purpose of investigating the effects of Rosa damascena Mill. and Rosa alba L. essential oils on the viral reproduction of susceptible (Victoria) and acyclovir-resistant (R-100) strains of HSV-1 replication in vitro, individually and in combination with acyclovir. Methods: Cytopathic effect inhibition test was used for assessment of antiviral activity of the oils, and the three-dimensional model of Prichard and Shipman was applied to evaluate the combined effect of oils with ACV on HSV-1 replication. Results: Both oils do not affect the replication of viral strains; they are able to influence only viral adsorption and extracellular virions and protect healthy cells from subsequent infection. In combination with lower doses of acyclovir, both oils demonstrate a significant synergistic effect on the replication of HSV-1, which is more contagious than the Victoria strain. Conclusions: The nonspecific mechanism of the reduction in viral reproduction caused by rose oils and the synergistic effect of their co-administration with the lower doses of specific inhibitor ACV makes them suitable therapeutics for overcoming viral resistance to HSV-1 infections.

Rose Flowers-A Delicate Perfume or a Natural Healer?

Plants from the Rosacea family are rich in natural molecules with beneficial biological properties, and they are widely appreciated and used in the food industry, perfumery, and cosmetics. In this review, we are considering Rosa damascena Mill., Rosa alba L., Rosa centifolia L., and Rosa gallica L. as raw materials important for producing commercial products, analyzing and comparing the main biological activities of their essential oils, hydrolates, and extracts. A literature search was performed to find materials describing (i) botanical characteristics; (ii) the phytochemical profile; and (iii) biological properties of the essential oil sand extracts of these so called “old roses” that are cultivated in Bulgaria, Turkey, India, and the Middle East. The information used is from databases PubMed, Science Direct, and Google Scholar. Roses have beneficial healing properties due to their richness of beneficial components, the secondary metabolites as flavonoids (e.g., flavones, flavonols, anthocyanins), fragrant components (essential oils, e.g., monoterpenes, sesquiterpenes), and hydrolysable and condensed tannins. Rose essential oils and extracts with their therapeutic properties—as respiratory antiseptics, anti-inflammatories, mucolytics, expectorants, decongestants, and antioxidants—are able to act as symptomatic prophylactics and drugs, and in this way alleviate dramatic sufferings during severe diseases.

Carotenoid, Carotene and Anthocyanin Levels of Naturally Grown old Garden Roses (Rosa ssp.) in Van

Secondary metabolites especially phenolic compounds, flavonoids, tannins, and terpenoids have potential antioxidants and antimicrobial activity. Carotenoids are important antioxidants and bioactive compounds supplying to the health benefits of different foods and rosehips known for high bioactive content. Anthocyanins have physiological importance because of their abilities to protect leaves from photooxidative injuries without significantly compromising photosynthesis. Numerous studies shown that roses are rich sources of bioactive compounds. The genus Rosa contains various species that are widely grown in Europe, Asia, The Middle East and North America. In this study it was aimed that determination of carotenoid, carotene and anthocyanin amounts of naturally growing old garden roses species in Van ecological conditions. In this study eleven species of rosehips (Rosa damascena, Rosa damascena var. semperflorens, Rosa laxa ssp. harputensis, Rosa alba, Rosa multiflora, Rosa pisiformis, Rosa foetida, Rosa foetida var. bicolor, Rosa hemisphaerica, Rosa hemisphaerica var. plena hort, Rosa heckellana subsp. vanheurckiona) naturally grown in Van conditions were used as plant material. The fresh leaves (100-200 mg), immediately after harvesting, were homogenized by 80% aqueous acetone and filtered by white tape filter paper. In the extracts, carotenoid, carotene and anthocyanin levels were determined by using UV spectrophotometer in 470 nm, 537 nm, 647 nm, 663 nm wavelengths respectively. As a result, the highest and lowest carotenoid levels were found as 3.18 µg/ml and 0.59 µg/ml in R. heckellana subsp. vanheurckiona and R. damascena var. semperflorens. The highest anthocyanin level was determined in R. damascena as 0.06 µg/ml.

Comparative Study of Phytochemical Profiles and Antioxidant Properties of Hydrosols from Bulgarian Rosa Alba L. and Rosa Damascena Mill.

This study assessed phytochemical profile and antioxidant capacity of hydrosols, obtained by water-steam distillation of Rosa alba L. and Rosa damascena Mill. plants, grown in experimental field of the Institute of Rose and Essential Oil Plants, Bulgaria. The identification of hydrosols’ compounds was performed using 7890A/5975 GC-MS system, the total phenolic content (TPC) was determined quantitatively using the Folin Ciocalteu reagent, with Gallic acid as the standard and the antioxidant capacity of both hydrosols in concentration of 0.3 % up to 15 % were tested in liposomal suspension, and in systems generating either hydroxyl and superoxide anion radicals. The results showed that hydrosols were rich in geraniol (42.55 % for Rosa alba L., and 27.25 % for Rosa damascena Mill.) and citronellol (28.70 % in both hydrosols). The hydrosolic TPC of Rosa alba L. and of Rosa damascena Mill. were found to be 72 and 32.52 μg/ml of the Gallic acid equivalent, respectively. Both hydrosols demonstrated good capacity to inhibit Fe2+/ascorbic acid - induced lipid peroxidation in egg liposomal model system as the effect of Rosa alba L. hydrosol in all tested concentrations was higher than those of Rosa damascena Mill. However, Rosa damascena Mill. demonstrated better •OH scavenger effect than that of Rosa alba L. These results suggest that the hydrosols from Rosa alba L. and Rosa damascena Mill. have well-expressed antioxidant properties that could be used as antioxidant supplements in conditions with oxidative stress ethology.

Cytotoxic and genotoxic potential of Bulgarian Rosa alba L. essential oil – in vitro model study

ABSTRACTRosa alba L., also known as the white oil-bearing rose, has been cultivated in relatively small areas of Europe – predominantly in the Rose Valley of Bulgaria. An increasing number of studies in vitro and in vivo, including clinical studies, have demonstrated the therapeutic efficacy of rose oils in recent years. However, little is known about the cytotoxic and genotoxic potential of the phytocomplex oil extract derived from Rosa alba L. The aim of the present work was to investigate the cytotoxicity and clastogenic effects of Rosa alba L. essential oil and its main constituent – geraniol, as well as citral A, associated with allergies and contact dermatitis. We used classical cytogenetic methods and comet assay. 1-Methyl-3-nitro-1-nitrosoguanidine was used as a standard mutagen. The data showed that R. alba L. essential oil (in concentrations up to 1000 μg/mL) did not exhibit a statistically significant cytotoxic effect. The essential oil did not significantly increase the level of mitotic disturbances (micronuclei and aneuploidy effects) and had no significant effect on the induction of chromatid aberrations, compared to the untreated control sample. Only geraniol and citral A (in the concentrations used) increased significantly the percentage of migrated DNA in the comet tail, compared to the whole oil extract. This study gives a reason to believe that R. alba L. oil has potential as a supplementary component in some therapeutic strategies. It would be harmless to normal cells and tissues, but with potential for additive or synergistic cytotoxicity against cancer cells.

Interspecific Interaction Between Phytoseiulus macropilis and Neoseiulus californicus (Acari: Phytoseiidae) Preying on Tetranychus urticae (Acari: Tetranychidae) on Rosebush Growing in Greenhouse

Greenhouses provide favorable conditions to grow roses (Rosa spp.) but also for the pest mite Tetranychus urticae Koch (Acari: Tetranychidae). Although chemical control continues to be used against this pest, consumer demand has encouraged research on less aggressive agricultural practices and biological control is now a viable option. The objective of this study was to investigate biological control of the two-spotted mite, in rosebush growing in greenhouse, by Phytoseiulus macropilis (Banks) and Neoseiulus californicus (McGregor) (Acari: Phytoseiidae), individually or in combination. Potted rosebushes (Rosa alba L., Rosaceae) were used in five treatments: 1 – control group, rosebushes only with T. urticae; 2 – rosebushes with T. urticae and N. californicus; 3 – rosebushes with T. urticae and P. macropilis; 4 – rosebushes with T. urticae, N. californicus, and, after 4 weeks, P. macropilis and 5 – rosebushes with T. urticae, N. californicus, and P. macropilis. Biological control was evaluated by counting live mites. The results showed that both predatory mites were efficient in the control of the two-spotted mite on rosebushes cultivated in the greenhouse, either alone or in combination, but, when only P. macropilis was released, this predaceous mite was more efficient than N. californicus, at either low or high prey density, but the N. californicus can survive for longer in the absence of prey or in its low presence, for being a generalist predatory mite.