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1.
Food Res Int ; 160: 111715, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36076410

RESUMO

Valorization of botanicals for the development of natural food-grade ingredients is an important task in terms of sustainability and processing waste reduction. In this study, Roman chamomile (Chamaemelum nobile L.) herb was collected at six different vegetation phases in the period 26 May - 23 August 2019 and subjected to biorefining into the several valuable fractions. The yield of hydro-distilled essential oil (EO) was in the range of 0.22% (intensive vegetative growth) to 0.80% (full flowering). Angelic, isobutyric, butyric and methacrylic acid esters and some monoterpene and sesquiterpene derivatives were the major EO constituents: 3-methylpentyl angelate (20.11-27.56%), methallyl angelate (7.28-10.33%), isoamyl angelate (5.57-9.02%), isobutyl angelate (4.84-6.79%), 2-methylbutyl angelate (3.11-6.32%), 3-methylamyl methacrylate (5.04-6.17%), 3-methylpentyl isobutyrate (4.29-6.64%), 3-methylamyl isobutyrate (4.29-6.64%), α-pinene (1.61-6.37%) and pinocarvone (1.46-4.67%). In order to valorize water soluble and solid EO distillation residues their antioxidant potential was evaluated by several in vitro assays: water extracts were considerably stronger antioxidants than acetone extracts isolated from the solid residues. Water extracts of the plants collected at flowering phases were the strongest antioxidants; their TPC, FRAP and ORAC values were up to 143.2 mg gallic acid equivalents/g, 650, and 5601 µmol TE/g dry extract, respectively, while effective concentrations (EC50) of DPPH• and ABTS•+ scavenging, were down to 0.59 and 0.49 mg/mL, respectively. Among 7 tentatively identified by UPLC/Q-TOF/MS phenolic constituents the intensity of molecular ion of 3,5-dicaffeoyl quinic acid was the largest. The results obtained may assist for developing flavorings, antioxidants and health beneficial preparations from C. nobile extracts.


Assuntos
Chamaemelum , Óleos Voláteis , Antioxidantes/química , Chamaemelum/química , Isobutiratos , Odorantes , Água
2.
Molecules ; 27(2)2022 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-35056665

RESUMO

The flowers of Narcissus poeticus are used for the isolation of valuable fragrance substances. So far, as the majority of these substances consist of volatile and sensitive to heat compounds, there is a need of developing effective methods for their recovery. In this study, freeze-dried N. poeticus inflorescences were extracted with pure supercritical CO2 (SFE-CO2) and its mixture with 5% co-solvent ethanol (EtOH) at 40 °C. Extract yields varied from 1.63% (12 MPa) to 3.12% (48 MPa, 5% EtOH). In total, 116 volatile compounds were identified by GC-TOF/MS in the extracts, which were divided into 20 different groups. Benzyl benzoate (9.44-10.22%), benzyl linoleate (1.72-2.17%) and benzyl alcohol (0.18-1.00%) were the major volatiles among aromatic compounds. The amount of the recovered benzyl benzoate in N. poeticus SFE-CO2 extracts varied from 58.98 ± 2.61 (24 MPa) to 91.52 ± 1.36 (48 MPa) mg/kg plant dry weight (pdw). α-Terpineol dominated among oxygenated monoterpenes (1.08-3.42%); its yield was from 9.25 ± 0.63 (12 MPa) to 29.88 ± 1.25 (48 MPa/EtOH) mg/kg pdw. Limonene was the major monoterpene hydrocarbon; (3E)-hexenol and heneicosanol dominated among alcohols and phenols; dihydroactinidiolide and 4,8,12,16-tetramethyl heptadecan-4-olide were the most abundant lactones; heptanal, nonanal, (2E,4E)-decadienal and octadecanal were the most abundant aldehydes. The most important prenol lipids were triterpenoid squalene, from 0.86 ± 0.10 (24 MPa) to 7.73 ± 0.18 (48 MPa/EtOH) mg/kg pdw and D-α-tocopherol, from 1.20 ± 0.04 (12 MPa) to 15.39 ± 0.31 (48 MPa/EtOH) mg/kg pdw. Aliphatic hydrocarbons (waxes) constituted the main part (41.47 to 54.93%) in the extracts; while in case of a 5% EtOH the percentage of alkanes was the lowest. The fraction of waxes may be removed for the separation of higher value fragrance materials. In general, the results obtained are promising for a wider application of SFE-CO2 for the recovery of fragrance substances from N. poeticus flowers.


Assuntos
Dióxido de Carbono/química , Flores/química , Narcissus/química , Odorantes/análise , Óleos Voláteis/isolamento & purificação , Compostos Fitoquímicos/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Perfumes/análise , Solventes/química
3.
Food Chem ; 348: 129047, 2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-33515951

RESUMO

Lipophilic extracts of Viburnum opulus (VOP) and Hippophae rhamnoides (SBP) berry pomace recovered by supercritical CO2 (SFE-CO2) were analysed by UPLC-Q-TOF-MS and GC × GC-TOF for their triacylglycerol, tocopherol, phytosterol and fatty acid composition, while oxidative stability was evaluated by Oxipres and Rancimat methods. SFE-CO2 recovered 16.99% and 26.24% of lipids from SBP and VOP, respectively. Linoleic, linolenic, oleic, palmitic and palmitoleic acids were major in SBP oil, while VOP oil was composed of almost equal amounts of linoleic and oleic acids. Therefore, remarkably higher diversity of triacylglycerols was identified in SBP. The content of ß-sitosterol and α-tocopherol was 359.5-514.5 and 65.38-118.6 mg/100 g, respectively. Hydrocarbons were other quantitatively important lipophilic components, including health beneficial squalene. All extracts improved oxidative stability of mayonnaise. The extracts of berry processing by-products by green extraction method contain valuable bioactive constituents and could be of high interest for applications in functional foods and nutraceuticals.


Assuntos
Dióxido de Carbono/química , Suplementos Nutricionais/análise , Frutas/química , Hippophae/química , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Viburnum/química , Alimentos , Interações Hidrofóbicas e Hidrofílicas
4.
Food Chem Toxicol ; 129: 269-280, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31029727

RESUMO

Essential oils of Nepeta cataria var. citriodora, N. transcaucasica, N. melissifolia, N. sibirica and N. nuda were investigated. The yields of EO were from 0.78 (N. nuda) to 5.94 (N. cataria) mg/g plant dry weight (pdw). In total, 143 compounds were identified and quantified in Nepeta plant EOs by GC-MS/FID. 4aα,7α,7aß-Nepetalactone (NL) was dominant constituent in N. cataria and N. nuda EO (50.16 and 55.72%, respectively) followed by 4aα,7α,7aα-NL (35.64 and 6.20%, respectively); other quantitatively important compounds were ß-caryophyllene, caryophyllene oxide, some monoterpene alcohols and their aldehydes. N. transcaucasica EO was composed mainly of citronellol (17.69%), 4aα,7ß,7aα-NL (14.34%), geranial (9.05%) and geranyl acetate (8.20%), whereas EOs of N. melissifolia and N. sibirica contained high percentages of 1,8-cineole (37.35 and 42.58%, respectively) and caryophyllene oxide (22.06 and 20.35%, respectively). In order to valorize EO distillation residues their antioxidant potential was evaluated by several in vitro assays: water extracts were considerably stronger radical scavengers than acetone extracts isolated from the solid EO distillation residue. The bioactivities and toxicological data of Nepeta spp. and their main EO components were assessed based on the most recently reported data.


Assuntos
Antioxidantes/toxicidade , Nepeta/química , Óleos Voláteis/análise , Óleos Voláteis/toxicidade , Cromatografia Gasosa-Espectrometria de Massas/métodos , Lituânia , Nepeta/classificação , Óleos de Plantas/química , Especificidade da Espécie
5.
PLoS One ; 13(5): e0196757, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29771946

RESUMO

BACKGROUND: The essential oils of Cymbopogon citratus (CC), Pelargonium graveolens (PG) and Vetiveria zizanioides (VZ) are commonly used topically to prevent mosquito bites and thus the risk of infection by their vectored pathogens such as arboviruses. However, since mosquito bites are not fully prevented, the effect of these products on the level of viral infection remains unknown. OBJECTIVES: To evaluate in vitro the essentials oils from Reunion Island against one archetypal arbovirus, the Ross River virus (RRV), and investigate the viral cycle step that was impaired by these oils. METHODS: The essential oils were extracted by hydrodistillation and analyzed by a combination of GC-FID and GC×GC-TOF MS techniques. In vitro studies were performed on HEK293T cells to determine their cytotoxicity, their cytoprotective and virucidal capacities on RRV-T48 strain, and the level of their inhibitory effect on the viral replication and residual infectivity prior, during or following viral adsorption using the reporter virus RRV-renLuc. RESULTS: Each essential oil was characterized by an accurate quantification of their terpenoid content. PG yielded the least-toxic extract (CC50 > 1000 µg.mL-1). For the RRV-T48 strain, the monoterpene-rich CC and PG essential oils reduced the cytopathic effect but did not display virucidal activity. The time-of-addition assay using the gene reporter RRV-renLuc showed that the CC and PG essential oils significantly reduced viral replication and infectivity when applied prior, during and early after viral adsorption. Overall, no significant effect was observed for the low monoterpene-containing VZ essential oil. CONCLUSION: The inhibitory profiles of the three essential oils suggest the high value of the monoterpene-rich essential oils from CC and PG against RRV infection. Combined with their repellent activity, the antiviral activity of the essential oils of CC and PG may provide a new option to control arboviral infection.


Assuntos
Repelentes de Insetos/farmacologia , Óleos Voláteis/farmacologia , Óleos de Plantas/farmacologia , Ross River virus/efeitos dos fármacos , Animais , Antivirais/farmacologia , Vetiveria/química , Culicidae/efeitos dos fármacos , Cymbopogon/química , Células HEK293 , Humanos , Mordeduras e Picadas de Insetos/tratamento farmacológico , Pelargonium/química , Reunião , Replicação Viral/efeitos dos fármacos
6.
Food Chem ; 260: 289-298, 2018 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-29699672

RESUMO

The aim of this study was to demonstrate the potential of extracts from Algerian Thymus munbyanus as a valuable source of antioxidants for use on an industrial level. To this end, a study was conducted on the composition and antioxidant activities of essential oils (EOs), pressurized liquid extracts (PLE) and supercritical fluid extracts (SFE-CO2) obtained from Thymus munbyanus subsp. coloratus (TMC) and subsp. munbyanus (TMM). EOs and SFE-CO2 extracts were analysed by GC-FID and GC×GC-TOFMS revealing significant differences. A successive extraction of the solid SFE-CO2 residue by PLE extraction with solvents of increasing polarity such as acetone, ethanol and water, was carried out. The extracts were evaluated for total phenolic content by Folin-Ciocalteu assay, while the antioxidant power was assessed by DPPH, FRAP, and ORAC assays. SFE-CO2 extracts were also analysed for their tocopherol content. The antioxidant activity of PLE extracts was found to be higher than that of SFE-CO2 extracts, and this increased with solvent polarity (water > ethanol > acetone). Overall, these results support the use of T. munbyanus as a valuable source of substances to be used on an industrial level as preservative agents.


Assuntos
Antioxidantes/farmacologia , Óleos Voláteis/química , Extratos Vegetais/química , Thymus (Planta)/química , Antioxidantes/química , Dióxido de Carbono/química , Fracionamento Químico/métodos , Cromatografia com Fluido Supercrítico/métodos , Etanol/química , Cromatografia Gasosa-Espectrometria de Massas , Óleos Voláteis/farmacologia , Fenóis/análise , Extratos Vegetais/farmacologia , Solventes/química
7.
Food Funct ; 7(8): 3555-65, 2016 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-27465989

RESUMO

Hydroxypropylation with propylene oxide followed by esterification with octenyl succinic anhydride (OSA) was used to produce modified potato starch derivatives suitable for the encapsulation of essential oils. Caraway essential oil (EO) was encapsulated by spray-drying into enzymatically hydrolyzed dual/single modified and native starches. The EO microencapsulation efficiency in different modified starches, the retention of volatile aroma compounds, the emulsion particle size and the microstructure of the spray-dried encapsulated powdered products, as well as the compositional aroma changes taking place during the processing and storage for up to 8 months have been estimated. The increase of OSA content from 0.97 to 2.52% in the P-native structure and from 0.91% to 2.66% in P-HP resulted in the significant increase in the encapsulating capacity, evaluated as a percentage of the total EO retained, from 61.6 to 88.0% and 73.8% to 84.0%, respectively. However, the compositional changes of the microencapsulated caraway EO constituents were not remarkable. Additionally, the effect of pure and encapsulated caraway EO products on the oxidative stability of commercial rapeseed oil and mayonnaise was evaluated using the instrumental Oxipres method and it was shown that they were more effective in emulsion type products by the up to 1.8-fold increase in the oxidative stability of mayonnaise.


Assuntos
Compostos de Epóxi/química , Manipulação de Alimentos , Óleos Voláteis/química , Amido/análogos & derivados , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Óleos de Plantas/química , Óleo de Brassica napus/química , Amido/química
8.
J Agric Food Chem ; 51(26): 7751-8, 2003 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-14664540

RESUMO

The influence of nitrogen fertilizers on the yield of crop, as well as on the production and composition of the essential oil and some other chemical characteristics of thyme, was investigated. Different levels of fertilizers (N = 0, 45, 90, and 135 kg x ha(-)(1)) were applied. It was found that fertilizers increase thyme crop, but differences in the yield of essential oil were not remarkable. However, the use of certain amounts of nitrogen fertilizers resulted in higher yields of essential oil obtainable from the cultivation area unit (dm(3) ha(-)(1)). Totally, 61 constituents were identified in thyme essential oil by capillary GC and GC-MS. Thymol was the dominating compound in the all analyzed oils (44.4-58.1%), followed by p-cymene (9.1-18.5%), gamma-terpinene (6.9-18.9%), and carvacrol (2.4-4.2%). Differences in the percentage of these and other compounds in thyme herb cultivated under different fertilization doses were not significant; very slight changes in the percentage composition were detected after drying. Some variations in the amount of individual constituents expressed in arbitrary units per kilogram of herb (which is almost equivalent to mg x kg(-)(1)) were observed. The highest amounts of sugars and sucrose, in particular, were determined in the second year of thyme cultivation. Differences in the content of dry soluble substances were not meaningful, and there was no effect of nitrogen fertilizers on this chemical characteristic. Some effect of fertilization on the content of vitamin C and carotenes was observed in the first year of thyme cultivation. It was determined that nitrogen fertilizers influence the amount of nitrates, which was highest in the second-year-first-harvest.


Assuntos
Fertilizantes , Nitrogênio/administração & dosagem , Thymus (Planta)/química , Thymus (Planta)/crescimento & desenvolvimento , Ácido Ascórbico/análise , Carboidratos/análise , Óleos Voláteis/análise , Óleos de Plantas/análise , Timol/análise
9.
J Agric Food Chem ; 51(13): 3840-8, 2003 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-12797753

RESUMO

The present study investigates the composition of volatile constituents and sensory characteristics of catnip (Nepeta cataria L.) grown in Lithuania. Hydrodistillation, simultaneous distillation-solvent extraction, static headspace, and solid phase microextraction methods were used for the isolation of aroma volatiles. Geranyl acetate, citronellyl acetate, citronellol, and geraniol were the major constituents in catnip. Differences in the quantitative compositions of volatile compounds isolated by the different techniques were considerable. A sensory panel performed sensory analysis of the ground herb, pure essential oil, and extract; aroma profiles of the products were expressed graphically, and some effects of odor qualities of individual compounds present in catnip on the overall aroma of this herb were observed.


Assuntos
Nepeta/química , Odorantes/análise , Adulto , Cromatografia Gasosa , Humanos , Pessoa de Meia-Idade , Extratos Vegetais/química , Olfato , Paladar , Volatilização
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