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The in viro antioxidant, anti-inflammatory, anti-hyperglycaemic, and anti-acetylcholinesterase activities of the essential oils (EOs) isolated from six Lamiaceae species (Thymbra capitata,. Thymus albicans, Th. caespititius, Th. carnosus, Th. lotocephalus and Th. mastichina) grown in Portugal, were evaluated. Th. caespititius and T. capitata carvacrol/thymol-rich EOs showed the best capacity for preventing lipid peroxidation, and scavenging the 2,2'-azino- bis(3-ethylbenzothiazoline-6-sulphonid acid) (ABTS) and peroxyl free radicals, as well as for inhibiting lipoxygenase and a-amylase. However, Th. caespititius and Th. lotocephalus 1,8-cineole and linalool rich EOs were the best inhibitors of a-glucosidase. T capitata, Th. lotocephalus and Th. albicans EOs were the: most active for inhibiting acetyleholinesterase. Th. caespititius and Th. mastichina EOs were the main scavengers of nitric oxide (NO) radicals. The comparison between the present data with a survey of the existing literature on the in vitro biological activities of the essential oils isolated from the same species from Portuguese origin, using other.methodologies, showed some differences. For instance the use of two oxidizable substrates (egg yolk andlecithin liposomes) led to distinct results mainly for those samples with relatively low activity. In addition, the EOs capacity for scavenging peroxyl radicals-was also influenced by the presence of cyclodextrins, as a synergism seemed to occur between EOs and those carbohydrates.

The objective of the present work was to develop strategies for increasing the shelf-life of red raspberries (Rubus idaeus L.), by preventing microorganism growth.; Results: Fruits coated with alginate plus lemon essential oil (0.2%) or orange essential oil (0.1%) after 15 days of storage had less red skin than the remaining samples. The less red color verified in these samples was also coincident with the lower concentration of anthocyanins at the end of the experiment as well as the lower capacity for scavenging ABTS free radicals or quenching singlet oxygen. Cyanidin and pelargonidin glucosides were found in raspberries fruits. The edible coatings supplemented with the essential oil of orange either at 0.1% or 0.2% were very efficient for controlling yeast and mold growth after 15 days of storage. To control the development of aerobic mesophilic bacteria the use of essential oil of lemon 0.2% and essential oil of orange 0.1% were the most efficient.; Conclusion: The application of the film improved post-harvest quality of raspberry, since the addition of essential oils of citrus films promoted to the inhibitory effect of fungi and bacteria growth after 15 days of storage, without changing quality parameters. © 2016 Society of Chemical Industry.; © 2016 Society of Chemical Industry.

The chemical variability and antioxidant activity of the flower and leaf essential oils (EOs) of Ammoides pusilla, collected at Algeria was evaluated. The EOs were isolated by hydrodistillation and analyzed by Gas Chromatography (GC) and Gas Chromatography-Mass Spectrometry (GC-MS). Antioxidant activity was assessed by DPPH, ABTS, Reducing Power and TBARS assays. Oxygen-containing monoterpenes (54-77%) dominated all but one A. pusilla leaf EOs, and in two flower EOs (53% both). Thymol dominated in practically all leaf and flowers EOs, but cumin alcohol, p-cymene and limonene attained also relatively high percentages in some EOs. A strong negative correlation (p50 values of ABTS, DPPH, and hydroxyl scavenging activity and the percentages of p-cymene and cumin alcohol present in EOs were observed, showing that higher levels of these monoterpenes were responsible for the best activities found. In spite of this finding, the antagonism and/or synergism between EO components must be taken into account, since the EO activity can only be considered as a whole. Moreover, given the EOs chemical variability their use as antioxidants, should be preceded by their chemical evaluation.

Edible coating formulations have been developed to increase shelf-life of some horticultural products. The objective of this research was to study the effect of edible coatings based on sodium alginate (AL) and pectin (PE) enriched with essential oils constituents (citral and eugenol) on the shelf-life extension of strawberries. AL and PE were tested at 1 and 2% (w/v) and were enriched with eugenol (Eug) at 0.1 and 0.2% and citral (Cit) at 0.15 and 0.3%. Strawberries were dipped in those solutions for 2 min, then stored at 0.5 °C. Measurements of color CIE (L*, a*, b*, h°, C*), firmness, soluble solids content (SSC), weight loss, trolox equivalent antioxidant capacity (TEAC), microbial growth and taste panels were accomplished at 0, 7 and 14 d storage. With those quality characteristics, hierarchical cluster analysis formed 3 groups either for AL or PE based edible coatings. Taking into account the mean closest values to the one at harvest for color, higher value for firmness, SSC and antioxidant activity, and lower value for weight loss and microbial spoilage, the best group was selected. From the selected groups, the 2 edible coating formulations which had higher score on taste panels were considered the best for preserving quality through shelf-life of strawberries. Those edible coatings were for AL the AL 2% + Eug 0.1%; AL 2% + Cit 0.15% + Eug 0.1% and for PE the PE 2% + Eug 0.1%; PE 2% + Cit 0.15%.

Essential oils are complex mixtures of volatile compounds with diverse biological properties. Antimicrobial activity has been attributed to the essential oils as well as their capacity to prevent pathogenic microorganisms from forming biofilms. The search of compounds or methodologies with this capacity is of great importance due to the fact that the adherence of these pathogenic microorganisms to surfaces largely contributes to antibiotic resistance. Superparamagnetic iron oxide nanoparticles have been assayed for diverse biomedical applications due to their biocompatibility and low toxicity. Several methods have been developed in order to obtain functionalized magnetite nanoparticles with adequate size, shape, size distribution, surface, and magnetic properties for medical applications. Essential oils have been evaluated as modifiers of the surfacemagnetite nanoparticles for improving their stabilization but particularly to prevent the growth of microorganisms. This review aims to provide an overview on the current knowledge about the use of superparamagnetic iron oxide nanoparticles and essential oils on the prevention of microbial adherence and consequent biofilm formation with the goal of being applied on the surface of medical devices. Some limitations found in the studies are discussed. info:eu-repo/semantics/publishedVersion

This work reviews the new isolated cembranoid derivatives from species of the genera Sarcophyton, Sinularia, and Lobophytum as well as their biological properties, during 2016–2018. The compilation permitted to conclude that much more new cembranoid diterpenes were found in the soft corals of the genus Sarcophyton than in those belonging to the genera Lobophytum or Sinularia. Beyond the chemical composition, the biological properties were also reviewed, namely anti-microbial against several Gram-positive and Gram-negative bacteria and fungi, anti-inflammatory and anti-tumoral against several types of cancer cells. In spite of the biological activities detected in almost all samples, there is a remarkable diversity in the results which may be attributed to the chemical variability that needs to be deepened in order to develop new molecules with potential application in medicine.

Myrtus communis L. (myrtle) and Myrtus nivellei Batt. & Trab. (Saharan myrtle) have been used in folk medicine for alleviating some ailments. M. communis is largely distributed in the Mediterranean Basin, whereas M. nivellei is confined in specific zones of the central Saharan mountains. The chemical composition and antioxidant activity of berry and leaf extracts isolated from myrtle are deeply documented, whereas those isolated from Saharan myrtle extracts are less studied. In both species, the major groups of constituents include gallic acid derivatives, flavonols, flavonol derivatives, and hydroxybenzoic acids. In coloured berries, anthocyanins are also present. In M. nivellei extracts are reported for some compounds not described in M. communis so far: 2-hydroxy-1,8-cineole-β-d-glucopyranoside, 2-hydroxy-1,8-cineole 2-O-α-l-arabinofuranosyl (1→6)-β-d-glucopyranoside, rugosin A, and rugosin B. Berries and leaves extracts of both species had antioxidant activity. Comparative studies of the antioxidant activity between leaf and berry myrtle extracts revealed that leaf extracts are best antioxidants, which can be assigned to the galloyl derivatives, flavonols, and flavonols derivatives, although the ratio of these groups of compounds might also have an important role in the antioxidant activity. The anthocyanins present in myrtle berries seem to possess weak antioxidant activity. The antioxidant activity of sample extracts depended on various factors: harvesting time, storage, extraction solvent, extraction type, and plant part used, among other factors. Leaf extracts of myrtle revealed to possess anti-inflammatory activity in several models used. This property has been attributed either to the flavonoids and/or hydrolysable tannins, nevertheless nonprenylated acylphloroglucinols (e.g., myrtucommulone and semimyrtucommulone) have also revealed a remarkable role in that activity. The biological activities of myrtle extracts found so far may direct its use towards for stabilizing complex lipid systems, as prebiotic in food formulations, and as novel therapeutic for the management of inflammation.

Myrtus communis L. (myrtle) and Myrtus nivellei Batt. & Trab. (Saharan myrtle) have been used in folk medicine for alleviating some ailments. M. communis is largely distributed in the Mediterranean Basin, whereas M. nivellei is confined in specific zones of the central Saharan mountains. The chemical composition and antioxidant activity of berry and leaf extracts isolated from myrtle are deeply documented, whereas those isolated from Saharan myrtle extracts are less studied. In both species, the major groups of constituents include gallic acid derivatives, flavonols, flavonol derivatives, and hydroxybenzoic acids. In coloured berries, anthocyanins are also present. In M. nivellei extracts are reported for some compounds not described in M. communis so far: 2-hydroxy-1,8-cineole-β-d-glucopyranoside, 2-hydroxy-1,8-cineole 2-O-α-l-arabinofuranosyl (1→6)-β-d-glucopyranoside, rugosin A, and rugosin B. Berries and leaves extracts of both species had antioxidant activity. Comparative studies of the antioxidant activity between leaf and berry myrtle extracts revealed that leaf extracts are best antioxidants, which can be assigned to the galloyl derivatives, flavonols, and flavonols derivatives, although the ratio of these groups of compounds might also have an important role in the antioxidant activity. The anthocyanins present in myrtle berries seem to possess weak antioxidant activity. The antioxidant activity of sample extracts depended on various factors: harvesting time, storage, extraction solvent, extraction type, and plant part used, among other factors. Leaf extracts of myrtle revealed to possess anti-inflammatory activity in several models used. This property has been attributed either to the flavonoids and/or hydrolysable tannins, nevertheless nonprenylated acylphloroglucinols (e.g., myrtucommulone and semimyrtucommulone) have also revealed a remarkable role in that activity. The biological activities of myrtle extracts found so far may direct its use towards for stabilizing complex lipid systems, as prebiotic in food formulations, and as novel therapeutic for the management of inflammation.

[Background]: Essential oils (EOs) have shown antimicrobial, antioxidant, and antiproliferative activity, which may, alone or in combination with other substances, potentially be used for the development of new drugs. However, their chemical variability, depending on the species, varieties, or geographical origin (among other factors) determines different bioactivities that need to be evaluated., [Methods]: The antioxidant activity of Corymbia citriodora and eight Eucalyptus species EOs was determined using two different methods: the scavenging ability of 2,20-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS+•) and peroxyl free radicals or oxygen radical absorbance capacity (ORAC). Antibacterial activity was evaluated using the microorganisms Streptococcus pneumoniae (strains D39 and TIGR4), and Haemophilus influenza (strain DSM 9999). The essential oils’ minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) was assessed using a microdilution method. The antiproliferative activity was determined using the THP-1 cell line (human acute monocytic leukaemia) with methylthiazolyldiphenyl-tetrazolium bromide assay (MTT)., [Results]: Corymbia citriodora and Eucalyptus viminalis EOs showed the highest ABTS and peroxyl free radical scavenging capacity. Eucalyptus globulus EO showed a high potential to treat Streptococcus pneumoniae infections. Haemophilus influenzae was the respiratory pathogen that showed the highest resistance to all EOs, including tea tree EO. After 96 h of incubation, at 25 µg/mL, Eucalyptus radiata and Eucalyptus viminalis EOs showed highest cytotoxic activity against the THP-1 cell line., [Conclusions]: Despite their specific bioactivities, no single EO showed simultaneously good antioxidant, antimicrobial, and antiproliferative activity., This study was partially funded by CESAM (UID/AMB/50017-POCI-01-0145-FEDER-007638), to FCT/MCTES through national funds (PIDDAC), and co-funding by the FEDER within the PT2020 Partnership Agreement and Compete 2020, and by the Fundação para a Ciência e a Tecnologia (FCT), under the projects UID/BIA/04325/2013—MEDTBIO, and UID/BIM/04773/2013 CBMR

12 Páginas.-- 4 Figuras.-- 2 Tablas, The emergence of multidrug-resistant bacteria has prompted the development of alternative therapies, including the use of natural products with antibacterial properties. The antibacterial properties of Zantaz honey produced in the Moroccan Atlas Mountains against Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus was evaluated and analyzed using chemometric tools. Minimum inhibitory concentration (MIC) and Minimum bactericidal concentration (MBC) against S. aureus were the lowest (112.5 ± 54.5 mg/mL), revealing that this species was most sensitive to Zantaz honey. P. aeruginosa showed an intermediate sensitivity (MIC= 118.75 ± 51.9 mg/mL), while E. coli was the most resistant to treatment (MIC = 175 ± 61.2 mg/mL). Content of monosaccharides, certain minerals, and phenolic compounds correlated with antibacterial activity (p < 0.05). Principal component analysis of physicochemical characteristics and antibacterial activity indicated that the parameters most associated with antibacterial activity were color, acidity, and content of melanoidins, fructose, epicatechin, methyl syringate, 4-coumaric acid, and 3-coumaric acid., This research was funded by the C.S.I.C. Program for Scientific Cooperation for Development (Program I-COOP + 2018) and CEF-Forest Research Centre is a research unit funded by Fundação para a Ciência e a Tecnologia I.P. (FCT), Portugal: UIDB/00239/2020 and. UIDB/05183/2020.

The volatiles from 24 propolis samples collected from different geographical locations in Morocco were evaluated. Propolis volatiles isolated by hydrodistillation and analyzed by gas chromatography (GC) and gas chromatography–mass spectrometry (GC-MS). Cluster analysis based on propolis samples’ volatile chemical composition defined two main uncorrelated clusters. Cluster I, with 23 of the 24 samples analyzed, included three subgroups, Ia, Ib1 and Ib2, dominated by βeudesmol (11–30%), cedrol (7–40%) and n-tricosane (6–34%), respectively. Cluster II included just one sample, with ar-curcumene (32%) as the main component. The results obtained contributed to increase the knowledge on the chemical composition and variability of Moroccan propolis samples. The volatile profile of these samples was distinct from those of Algeria, Canary Islands and Ethiopia, the sole African propolis volatiles studied so far. POCI-01-0145-FEDER-007638; Fundação para a Ciência e a Tecnologia (FCT) /MCTES through national funds (PIDDAC), the co-funding by the FEDER, within the PT2020 Partnership Agreement and Compete 2020 info:eu-repo/semantics/publishedVersion

Honey with Bupleurum spinosum (zandaz) as a main pollen source has not been the subject of previous detailed study. Therefore, twelve Moroccan samples of this honey were subjected to melissopalynological, physicochemical and microbiological quality characterization, as well as antioxidant activity assessment. From a quality point of view, almost all samples were within the limits established by Codex Alimentarius, and/or the European legislation. All samples presented predominance of B. spinosum pollen (more than 48%). Relatively high levels of trehalose (1.3–4.0 g/100 g) and melezitose (1.5–2.8 g/100 g) were detected. Those sugars, not common in monofloral honeys, could be used as an important factor to discriminate zandaz honey. Flavonoid content correlated positively with the honey color, melanoidin and polyphenol content, and negatively with the IC50values of scavenging ABTS (2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) free radicals, while proline amount correlated negatively with IC50values of nitric oxide scavenging activity and chelating power. This correlation supports the use of anti-oxidant activities as important variables for PCA (principal component analysis). Both components explained 70% from the given data, and showed certain homogeneity upon analyzed samples independent of the region, suggesting the importance of B. spinosum nectar in the resulting honey characteristics. The authors are grateful to Fundação para a Ciência e Tecnologia for Research Center Grant UID/BIM/04773/2013 CBMR 1334; UID/AGR/00239/2013; UID/BIA/04050/2013 (POCI-01-0145-FEDER-007569); and to ERDF through the COMPETE2020 – Programa Operacional Competitividade e Internacionalização (POCI). info:eu-repo/semantics/publishedVersion

Propolis is known to possess antioxidant activity. However, there is no information on this activity in emulsions O/W. The protective effect of propolis on the oxidation and rheological properties of emulsions O/W containing wheat germ and almond oils was evaluated. Emulsions O/W were prepared with different concentration of propolis extract, almond oil and wheat germ oil. All emulsions physically stable without phase separation were stored at 37 °C for 9 weeks. Chemical composition of propolis was established by Gas chromatography coupled to mass spectrometry. Rheological characterization of different emulsions was performed evaluating consistency index and flow behavior index. The oxidation was monitored by measuring the lipid hydroperoxides and thiobarbituric acid-reactive substances (TBARS) methods. Flavonoids, phenolic acid esters, and aromatic acids were the main groups of compounds found in propolis. The results showed that popolis was good antioxidant in the concentration of 0.02 and 0.04% when lipid phase was constituted by almond oil. The rheological behavior is typical of a non-Newtonian fluid, being almond oil more adequate for having a higher stable O/W emulsion. Keywords: Emulsion, Flavonoids, Phenolic acid esters, Almond oil, Wheat germ oil, Natural antioxidant

This study aimed to characterize the pollen and physicochemical profiles, and to evaluate the antioxidant capacity of six samples of Moroccan honey. The pollen grains of Eragrostis spp. were predominant in all samples (from a minimum of 46.58 ± 1.59% to 72.72 ± 2.43% as a maximum), exceeding the minimum (generally 45%) required for the monoflorality nomination of a honey sample, and suggestion a case of newly reported honey. The analyzed samples had low diastase activity and hydroxymethylfurfural (HMF) content. Potassium was the dominant element in practically all samples, except the sample with the highest Eragrostis spp. pollen percentage, which showed sodium predominance. The honey color ranged from water white to light amber, and positively correlated the concentrations of phenols, proline and the capacity for scavenging free radicals. However, great variability observed in all the analyzed parameters, and could not be explained by the variability of the Eragrostis spp. pollen percentage, which suggests a hypothesis of low concentrated nectar. Practical applications: The melissopalynological profile of honey is an important parameter for determining the type of honey (multifloral, monofloral, blossom, honeydew) and its relationship to the botanical and geographical provenance. There is generally a relationship between the pollen profile of honey and the biological properties. The physicochemical characterization, antioxidant activity and melissopalynological profile of Eragrostis honey was reported for the first time in this study. These data intend to contribute for the introduction of a new type of honey labeled as Eragrostis honey. At the same time, the evaluation of the antioxidant activity may also trigger the search of other biological properties with medicinal attributes for the new Eragrostis ssp. honey. The authors thank to the Centro de Apoio Tecnológico Agro-Alimentar de Castelo Branco (CATAA) for the equipment availability for sugar determination. The authors would like to express their gratitude to Isabele Salavessa (IPCB Languages centre) for the English revision. The research unit Centro de Estudos Florestais is supported by the Portuguese National Funding Agency for Science, Research and Technology (Fundação para a Ciência e a Tecnologia – FCT), projects UID/AGR/00239–2013, UID/BIA/04325/2013 – MEDTBIO, UID/ Multi/04326/2013 and UID/BIA/04050/2013. info:eu-repo/semantics/publishedVersion

Opuntia ficus‐indica fruits have an important nutritional value and show several biological properties. This work studied the fruit physicochemical characteristics of two wild ecotypes (“Green” and “Orange”) and two cultivars (“Rossa” and “Gialla”) from Portugal. The results showed that the largest and heaviest fruits were those from ecotype “Orange,”, whereas the wild ecotype “Green” had fruits with firmer flesh. The fruit peels of cultivars “Rossa” and “Gialla” presented the highest fibre content. Glucose was the major carbohydrate in the fruits, particularly in the peels. Malic acid was the sole organic acid in both peels and pulps of all samples. The betacyanins’ content was higher in fruits of the “Rossa” cultivar, and the higher betaxanthins’ content was present in the peel of the cultivar “Gialla.” Peels of all samples generally had higher amounts of betalains than the pulps. The peel was a better scavenger of DPPH and ABTS free radicals than the pulp. PRACTICAL APPLICATION: The wastes of diverse food industries have revealed the presence of bioactive compounds with added value. The fruits of Opuntia ficus‐indica are appreciated for possessing biological attributes, nevertheless the peel generally is not used. The present work shows that the pigments (betalains) are predominantly found in the peel. Moreover, the in vitro antioxidant activity was also higher in this part of the fruit, independent on the ecotype or cultivar studied. Such results might trigger the interest for these residues from which pigments and bioactive compounds can be extracted, and, as extracts, can be used in diverse domains particularly in food and pharmaceutical industries.

The effects of optimized edible coatings based on sodium alginate (AL) or pectin (PE) with the essential oil constituent additives, citral (Cit) and eugenol (Eug), were studied on fresh raspberries quality during storage at 0.5 °C. Several formulations of edible coatings were used as treatments: AL and PE were tested at 1% and 2% (w/v) with Cit and Eug at minimum inhibitory concentrations (MIC) (0.15 and 0.1%, respectively), at double the MIC concentration and their combination at MIC. Raspberries were immersed in each solution (treatment) for 2 min, and then cooled at 0.5 °C. On days 0, 7, and 14th, samples were removed and used for the following physicochemical and biochemical analysis: color CIE ( L *, °hue), firmness, soluble solids concentration (SSC), weight loss, trolox equivalent antioxidant capacity (TEAC), microbial growth, and taste panels. Color parameter L * and TEAC were not significantly affected by the coatings. Cit at higher concentrations reduced °hue and firmness and increased weight loss. The SSC decreased mainly in controls. Edible coatings enriched with Cit and Eug were effective at reducing microbial spoilage. Taste panels showed lower scores in Cit 0.3% treatments and raspberries were considered not acceptable after 14 days storage. No significant differences were observed between PE and AL. Raspberries immersed in water (control + water) performed worse than fruit stored without any immersion or wash (control). With the results of the physicochemical and biochemical parameters measured, 3 similar treatment groups were formed by the principal component analysis (PCA) and hierarchical cluster analysis (HCA), either for AL or PE coatings. The group which had better performance was selected for AL- and PE-based edible coatings. From each group the two best edible coating formulations with the higher sensory evaluation were selected. Those confirmed that raspberries were better preserved in terms of general sensory attributes with coatings of AL 2% + Cit 0.15% and AL 2% + Eug 0.1%, and with PE 1% + Eug 0.1% followed by PE 1% + Cit 0.15% + Eug 0.1%.

The chemical compositions of essential oils of Lavandula angustifolia, Lavandula latifolia, Lavandula hybrida cultivar Grosso and cultivar Super, Thymus zygis with high proportions of thymol and linalool and Thymus hyemalis, from Murcia country (Spain), were studied in relative (%), absolute (mM) and chiral concentrations by GC/MS. Hyaluronidase inhibition and antioxidant activities of the essential oils were evaluated using ABTS•+, DPPH•, ORAC, chelating power, hydroxyl radical, nitric oxide, TBARS and reducing power assays. Linalool and linalyl acetate were the most abundant components in the Lavandula genus whereas thymol, linalool and 1,8-cineole were the most abundant molecules in the respective Thymus species. Chiral determination of the main components showed (+)-enantiomers like terpinen-4-ol, β-pinene, borneol and α-terpineol and (−)-enantiomers like linalool, linalyl acetate and camphene in Lavandula sp. In the case of Thymus sp. (+)-enantiomers like α-pinene, limonene, terpinen-4-ol and α-terpineol and (−)-enantiomers like borneol were found. Essential oils containing thymol were found especially powerful in all assays but chelating power, ORAC and hydroxyl radical scavenging assays. The capacity for inhibiting hyaluronidase showed that T. zygis with a high proportion of thymol was the most effective inhibitor. Essential oils containing thymol and linalool/linalyl acetate have a potential use as antioxidant agents. Thymol shows strong inhibition of hyaluronidase. Copyright © 2015 John Wiley & Sons, Ltd.

The present study was conducted to evaluate the in vitro antioxidant, anti-inflammatory and antimicrobial activities of the essential oils and crude ethanol extracts of Teucrium polium subsp. capitatum Briq. and Origanum floribundum Munby from Algeria. A total of 78 and 55 constituents were identified, representing 92 and 98.4 % of the total chemical composition of Teucrium and Origanum essential oils, respectively. Monoterpenes (22 %), sesquiterpenes (31.2 %) and oxygenated sesquiterpenes (25.5 %) dominated in the oil of T. polium with t-cadinol (18.3 %), germacrene D (15.3 %) and β-pinene (10.5 %) as predominant compounds; while monoterpenes (51.3 %) and oxygenated monoterpenes (45.2 %) were the most prominent groups in O. floribundum oil characterized by thymol (33.6 %), γ-terpinene (19.9 %) and p-cymene (15.5 %). The ethanol extracts were analyzed in terms of the dosage in total phenolic and flavonoids contents. Gallic acid equivalent representing total phenolic constituents of the extracts of...

Copyright © 2015 Maria Graça Miguel et al. The antioxidant and antiproliferative activities of the essential oils from Thymbra capitata and Thymus species grown in Portugal were evaluated. Thymbra and Thymus essential oils were grouped into two clusters: Cluster I in which carvacrol, thymol, p-cymene, α-terpineol, and γ-terpinene dominated and Cluster II in which thymol and carvacrol were absent and the main constituent was linalool. The ability for scavenging ABTS·+ and peroxyl free radicals as well as for preventing the growth of THP-1 leukemia cells was better in essential oils with the highest contents of thymol and carvacrol. These results show the importance of these two terpene-phenolic compounds as antioxidants and cytotoxic agents against THP-1 cells., This study was partially funded by Fundaçao para a Ciencia e Tecnologia (FCT), under Pest-OE/EQB/LA0023/2011 and UID/AMB/50017/2013

The beneficial effects of honey on human health have long been recognized. Today, many of those positive effects have been studied to elucidate its mode of action. This review briefly summarizes the best studied features of honey, highlighting it as an appealing alternative medicine. In these reports, the health benefits of honey range from antioxidant, immunomodulatory, and anti-inflammatory activity to anticancer action, metabolic and cardiovascular benefits, prebiotic properties, human pathogen control, and antiviral activity. These studies also support that the honey's biological activity is mainly dependent on its floral or geographic origin. In addition, some promising synergies between honey and antibiotics have been found, as well as some antiviral properties that require further investigation. Altogether, these studies show that honey is effectively a nutraceutical foodstuff. info:eu-repo/semantics/publishedVersion

Thymus is a widely distributed genus in the Mediterranean region with several species endemic to the Iberian Peninsula. The genetic relationships among the 12 major Thymus taxa, T. albicans, T. caespititius, T. camphoratus, T. capitellatus, T. carnosus, T.lotocephalus, T. mastichina L. ssp. mastichina, T. pulegioides, T. villosus ssp. lusitanicus, T. villosus ssp. villosus, T. zygis ssp. sylvestris and T. zygis ssp. zygis, which occur in Portugal were assessed by AFLP (Amplified Fragment Length Polymorphisms) markers. A general agreement was found between the genetic relationships estimated by the AFLP markers and the accepted Thymus taxonomy based on morphological traits and essential oil content. The AFLP markers also supported suggestions for refinement of the taxonomy of this genus.

Propolis and geopropolis are bee products (from honeybees and stingless bees, respectively) which are receiving increasing attention due to their reputed biological properties. Although several works have examined the chemical variability of propolis (in general), not so much is known about their volatile chemical profiles. The composition of volatile compounds in propolis can be affected in a number of ways, starting from the raw material used by different types of bees (honeybees or stingless bees) to the techniques used for their final isolation and analysis. This work gives an overview of the existing literature on propolis volatiles, their origin, bee producing species, plant sources and methodologies of extraction and analysis.

Royal jelly (RJ) has been used since ancient times in traditional medicine. It is a honeybee hypopharyngeal and mandibular gland secretion of young workers called nurses, and is a yellowish, creamy, acidic material with a slightly pungent odor and taste. RJ is primarily involved in prolonging the lifespan of the queen bee and for feeding young larvae. The composition of RJ varies depending on seasonal and regional conditions; it may contain proteins, lipids, sugars, vitamins (A, B5, C, D, E) and essential amino acids, particularly cystine, lysine and arginine. Investigations into the volatiles contained in RJ are scarce. From the few references we found in which the volatile fractions of RJ were determined, we can report that several factors can account for differences in the general volatile profile of RJ, such us honeybee species, harvesting time, region, storage conditions and extraction method. We found that the volatile fraction of RJ is composed of different compounds such as carboxylic acids (2-methylbutanoic acid, 3-methylbutanoic acid, pentanoic acid, 2-hexenoic acid…), phenols (hydroquinone), carbonyl compounds (ketones), esters, aldehydes and alcohols. In this chapter, based on bibliographic investigations from throughout the international literature, we detail findings related to the chemical composition of volatile organic compounds in RJ determined by chromatography coupled to mass spectrometry (GC-MS).

The combination of temperature and atmosphere composition for storage of Pyrus communis L. ‘Rocha’ treated with 1-methylcyclopropene was investigated. Fruits treated with 312 nl l−1 1-methylcyclopropene were stored at 0 ℃ and 2.5 ℃ in air and controlled atmosphere (CA) (3.04 kPa O2+ 0.91 kPa CO2). Fruits were removed from storage after 14, 26 and 35 weeks, transferred to shelf-life at approximately 22 ℃ and assessed for ripening and quality, symptoms of superficial scald and internal browning and the accumulation of biochemical compounds related to scald after 0, 1 and 2 weeks. Superficial scald occurred only in fruits stored for 35 weeks in air at 2.5 ℃. Levels of conjugated trienols and α-farnesene increased during the first 26 weeks in storage, remaining constant thereafter. During shelf-life, conjugated trienols were higher in fruits stored in air at 2.5 ℃. Internal browning developed in shelf-life after 26 weeks at 2.5 ℃. Pears in air at 2.5 ℃ were not able to stand a 2-week shelf-life after 35 weeks of storage, while fruits stored at 0 ℃ under CA ripened slowly after the same storage period. The retention of firmness during shelf-life of 1-methylcyclopropene-treated ‘Rocha’ pear can be overcome by elevating the storage temperature from 0 ℃ to 2.5 ℃, but CA is a required complement to avoid excessive softening after long-term storage. The ratio carotenoid/chlorophyll increased during storage and shelf-life, as plastids senesced. CA reduced the rate of chlorophyll loss during the first 14 weeks in storage, but its effect was reduced afterwards. ‘Rocha’ pear treated with 1-methylcyclopropene had a similar post-harvest behaviour during long-term storage at 0 ℃ in air or at 2.5 ℃ under CA.

The present study evaluated the physicochemical characteristics and antioxidant activity of 13 commercial honeys from diverse floral origin, produced in Portugal. The values of electrical conductivity of cardoon and pennyroyal honeys were superior to the maximum limits defined by European legislation. Citrus, strawberry tree, and 1 sample of lavender honeys had values of diastase activity below those determined by European legislation. Strawberry tree, pennyroyal, and cardoon honeys had the highest amounts of potassium that coincided with the highest electrical conductivity. Strawberry tree honey was the most effective as antioxidant along with cardoon and heather honeys. This ability was strongly correlated with the amounts of phenols and flavonoids and not with the levels of vitamin C or proline.

The strawberry tree (Arbutus unedo L) fruits are used in small quantities for fresh consumption despite their excellent flavor. The aim of this work was to evaluate the storage ability of strawberry tree fruits for fresh consumption. Harvested fruits were stored in polystyrene foam trays covered with two film types: linear low density polyethylene of 10 mu m thickness (PPL) or polyethylene film perforated with holes of 10 mm diameter spaced 50 mm (PP). Through 15 days storage at 0,3 and 6 degrees C, fruits were analyzed for quality parameters. The strawberry tree fruits presented relevant qualitative properties and were appreciated by panelists. Color parameters (L*, h degrees, C*) had higher decrease at 3 and 6 degrees C than at 0 degrees C. The degrees Brix almost did not change and firmness decreased mainly in the first 4 days storage. Ethanol and weight loss increased with temperature mostly from 3 to 6 degrees C. Strawberry tree fruits are a good source of ascorbic acid, glucose, fructose, anthocyanins and antioxidant activity. Those properties are maintained through 15 days storage at 0 degrees C followed by 3 degrees C. Film covers showed no significant differences between them. The temperature of 0 degrees C was the best for preservation of fruit quality through 15 days shelf-life. (C) 2013 Elsevier B.V. All rights reserved.

“Agua-mel” is a honey-based product produced in Portugal for ancient times. Several attributes have been reported to “agua-mel” particularly in the alleviation of simple symptoms of upper respiratory tract. Samples of “agua-mel” from diverse beekeepers from different regions of Portugal were studied in what concerns antimicrobial, antioxidant and antiviral properties. The amounts of phenol and brown pigment were also evaluated and correlated with the antioxidant activities. A great variability on the levels of these compounds was found among samples which were responsible for the variability detected also on the antioxidant activities, independent on the method used. Generally, antioxidant activity correlated better with brown pigments’ amount than with phenols’ content. The antimicrobial activity found for “agua-mel” samples confirm the virtues reported by popular findings. In addition, this work also reveals the antiviral properties of “agua-mel” evidenced by a decrease on the infectivity of the Qβ bacteriophage.

Due to the high perishability of raspberry fruit, this work was undertaken to study the effect of alginate and pectin based edible coatings enriched with essential oils components on their storage ability. Four formulations of edible coatings, selected in a previous work, were used: sodium alginate (AL) at 2% + eugenol (Eug) 0.1%, AL 2% + citral (Cit) 0.15%, Pectin (PE) 1% + Eug 0.1% and PE 1% + Cit 0.15% + Eug 0.1%. At 0, 5, 10 and 15 d, samples were taken to perform analysis of colour, firmness, soluble solids content (SSC), weight loss, microbial growth, phenolic compounds (total phenolics, flavonoids, anthocyanins), sugars, organic acids, antioxidant activity (TEAC and ORAC), acetaldehyde, CO2 production and sensory evaluation. Cytotoxicity of the edible coatings was also evaluated on THP-1 and Caco-2 cells. Results of this experiment showed that the edible coatings were not cytotoxic and generally did not significantly affect nutritional quality parameters. They were efficient in controlling microbial food spoilage. Acceptance by consumers of the coated raspberries was good up to 14 d, while control fruit were acceptable only till 7 d. The edible coating that best preserved quality was PE 1% + Cit 0.15% + Eug 0.1%. (C) 2016 Elsevier Ltd. All rights reserved.

Summary Biological properties of Moroccan propolis have been scarcely studied. In the present work, the total phenols and flavonoids from 21 samples of propolis collected in different places of Morocco or 3 supplied in the market were determined, as well as the in vitro capacity for inhibiting the activities of acetylcholinesterase, α-glucosidase, α-amylase, lipoxygenase, tyrosinase, xanthine oxidase and hyaluronidase. The results showed that samples 1 (region Fez-Boulemane, Sefrou city) (IC50 = 0.065, 0.006, 0.020, 0.050, 0.014 mg mL−1) and 23 (marketed) (IC50 = 0.018, 0.002, 0.046, 0.037, 0.008 mg mL−1) had the best in vitro capacity for inhibiting the α-amylase, α-glucosidase, lipoxygenase, tyrosinase and xanthine oxidase activities, respectively. A negative correlation between IC50 values and concentration of phenols, flavones and flavanones was found. These activities corresponded to the generally higher amounts of phenols and flavonoids. In the same region, propolis samples have dissimilar phenol content and enzyme inhibitory activities.

Agua-mel (honey–water) is a typical honey-based product produced by the Portuguese beekeepers, particularly in southern Portugal. Agua-mel was characterized by mineral content and volatiles contents. Mineral content evaluation was performed based on a random sampling of 14 samples from a total of 16 samples provided by local producers. Mineral content showed that potassium predominated in agua-mel samples (1270–4105 mg/kg). The concentration of aluminium in one sample was tenfold higher (5.8 mg/kg) than in the remaining samples (0.3–0.6 mg/kg). Agua-mel volatiles were isolated by hydrodistillation and analysed by gas chromatography (GC) and gas chromatography–mass spectrometry (GC–MS) from a subset of eight samples. Cluster analysis showed two poorly correlated clusters (S corr

The commercial essential oils of Citrus aurantium L., Cupressus sempervirens L., Eucalyptus globulus Labill., Foeniculum vulgare Mill. and Thymus vulgaris L., isolated by steam distillation by a company of Morocco were evaluated in terms of in vitro antioxidant activity through several methods. In vitro acetylcholinesterase inhibitory activity was also determined. Citrus limon (L.) Burm. f. oil was also studied, but it was obtained by peel expression. The best antioxidant was T. vulgaris oil, independent of the method used, mainly due to the presence of the phenolic monoterpenes thymol and carvacrol, which when studied as single compounds also presented the best activities. Concerning the acetylcholinesterase inhibition activity, E. globulus was the most effective. Nevertheless its main components 1,8-cineole and limonene were not the most active, a feature that corresponded to delta-3-carene.

The antioxidant properties of herbs and spices are important in the prevention of several diseases. Extracts from Foeniculum vulgare (Apiaceae), Dittrichia viscosa (Asteraceae), Origanum vulgare, Salvia officinalis, Thymbra capitata, Thymus camphoratus, Thymus carnosus and Thymus mastichina (Lamiaceae) were investigated for their antioxidant and anti-inflammatory activities. Some extracts were studied for the first time. Deodorized-, organic- and water-solvent extracts of dried and ground plant material were prepared using solvents of different polarity. The antioxidant activity was assessed by the diphenylpycrylhydrazyl (DPPH) radical method and scavenging of the superoxide anion radicals through an enzymatic hypoxanthine/xanthine oxidase system. The anti-inflammatory activity was evaluated by inhibition of 5-lipoxygenase. Total phenolic content was quantified by the Folin-Ciocalteu method. S. officinalis extracts were the best in scavenging DPPH radicals and superoxide anion radicals. O. vulgare and T. mastichina extracts were also effective as DPPH and superoxide scavengers, respectively. Deodorized chloroformic extracts from T. mastichina, T. camphoratus, T. carnosus, O. vulgare, F. vulgare and S. officinalis exhibited high ability for inhibiting lipoxygenase. Only in very few cases, a weak-moderate positive correlation was detected between the total phenol content and antioxidant activity. For 5-lipoxygenase inhibition, a negative correlation was detected in the majority of the extracts. (C) 2010 Elsevier B.V. All rights reserved.

Propolis is a natural honeybee product known to be beneficial for human health, with a complex chemical composition, highly dependent on the collection site. The objective of the present research was to evaluate phenols and antioxidant activity of propolis samples collected in three main areas of Algarve, South of Portugal. Water revealed to be less effective for extracting phenolic compounds from propolis than the methanol and water/ethanol. The last two were good extraction solvents of phenols. Nevertheless water/ethanol was the solvent chosen because it was able to extract phenols in considerable amounts being less toxic than methanol. In spring, higher amounts of phenols (total phenols, flavones, flavonols, flavanones and dihydroflavonols) were detected in hydro-alcoholic extracts of propolis than in winter. Among the three main areas of Algarve where samples were collected, those from Barrocal had the highest levels of polyphenols, independent on the season (winter or spring). Within each area, the levels of phenols changed according to the zone. Concerning antioxidant activity, samples from Barrocal presented better radical scavenging abilities than those from the remaining areas, independent on the antioxidant method and collection season. Such results correlated closely with the levels of total phenols, flavones and flavonols in samples.

Fertilization in citrus is a cultural practice with great importance as it affects significantly the quality of fruit. In this work we evaluated the effects of organic versus conventional farming systems on internal and external characteristics of citrus, with particular emphasis on vitamin C content. The study was carried out in different orchards of the Algarve region, in the south of Portugal. Fruits of different orchards were harvested at physiological maturity and submitted to physical and chemical analyses. The results showed that mineral fertilization led to fruits with greater weight and diameter, a thicker peel and a more intense colour. Compared with conventional production, fruits from organic farming had more soluble solids and a lower maturation index. The highest concentrations of vitamin C were recorded in fruits from organic farming, but the response depended on species and cultivar. Interreg III – CITRISAUDE SP5, P120/03 - Cooperação Transfronteiriça "Citrisaude – New post-harvest technologies to improve quality and safety in citrus"; Agro nº282 – Horticulture in Organic farming

Cyclodextrins are cyclic oligosaccharides of α-(1,4)-linked D-glucopyranose units in a ring formation. They are able to form inclusion complexes with a wide variety of molecules, improving their aqueous solubility and chemical stability, the dissolution and release rates of several molecules as well as suppressing their volatility and unpleasant odours or tastes. Thymol and carvacrol are two aromatic compounds present in the essential oils of Thymus and Origanum species, which show antioxidant properties. The main goal of this work was to evaluate the antioxidant ability of thymol and carvacrol and of the corresponding β-cyclodextrin complexes. Oxygen Radical Absorbance Capacity (ORAC), Trolox Equivalent Antioxidant Capacity (TEAC) and 2,2-diphenyl-2-picryl-hydrazil (DPPH) methods were used for evaluating the thymol and carvacrol and the β-cyclodextrin complexes scavenging free radicals capacity. With ORAC method, thymol showed better antioxidant activity than carvacrol, 47 and 33 μmol Trolox equivalent/mg (TE), respectively. Thymol- and carvacrol-β-cyclodextrin complexes maintained their capacity for scavenging the free radical with 47 and 28 μmol TE/mg, respectively. With TEAC method, thymol and carvacrol showed similar antioxidant activities: 421 and 450 μmol TE/mg, respectively. In contrast, carvacrol-β-cyclodextrin complex attained 494 μmol TE/mg while thymol complex showed only 184 μmol TE/mg. This complex seems to loose the capacity for scavenging free radicals. Different results were obtained with DPPH method. IC 50 values for thymol and the corresponding complex were similar 0.03 mg, whereas carvacrol and carvacrol-β-cyclodextrin complex showed an IC 50 =0.03 and 0.02 mg, respectively.

The effects of different essential oils, rich in oxygen-containing monoterpenes, isolated from three aromatic plants largely spread in Algarve (southern Portugal) were observed on Ceratitis capitata adults. The isolation of the essential oils were carried out by hydrodistillation and analyzed by GC and GC-MS. The most effective, in terms of mortality rate, was the oil of Mentha pulegium, mainly constituted by menthol, menthone, isomenthone and pulegone. Over 90 % of mortality was achieved after 48 hours of exposure to this essential oil. The remaining oils were not so effective, though always significantly superior to the control. They were mainly constituted by carvacrol (Thymbra capitata) and 1,8-cineole (Thymus albicans). It remains to clarify if the toxicity is due to a fumigant effector oral toxicity of the essential oils of M. pulegium and Thymbra capitata, as soon after the exposure, the Mediterranean fruit fly showed evident signs of loss of motor coordination and difficulty in flying.

The compositions of essential oils isolated from nine samples of three Thymus species (Thymus algeriensis, Thymus pallescens and Thymus dreatensis) were analysed by GC and GC-MS, and a total of 114 components were identified. T. pallescens collected from various regions showed a great similarity in their compositions and were characterised by carvacrol (44.4-57.7%), p-cymene (10.3-17.3%) and gamma-terpinene (10.8-14.2%) as the major components for four samples; only one sample was thymol-rich (49.3t) with a small amount of carvacrol (9.0%). On the other hand, T. algeriensis showed a chemical polymorphism, even for samples from the same location, and two new chemotypes for this species were proposed. Oxygen-containing monoterpenes were the predominant class (76.3%) in T. dreatensis oil, with linalool (30.4%), thymol (20.2%) and geraniol (19.6%) as the principal constituents. The oils were screened for their possible antioxidant activities by four complementary assays, namely DPPH free radical scavenging, hydroxyl radical scavenging, inhibition of lipid peroxidation and reducing power. The two new chemotypes of T algeriensis exhibited strong hydroxyl radical scavenging (IC(50) = 2.2-3.3 mu g/ml), but were not or only slightly active against the other radicals and exhibited a weak reducing power. Despite their chemical similarity, T. pallescens oils sometimes produced significant differences in their antioxidant activities. The essential oils were also screened for their antimicrobial activity against five bacteria (three Gram-positive and two Gram-negative) and one yeast (Candida albicans). The tested essential oils showed antimicrobial activity against the microorganisms used, in particular against two important pathogens, C. albicans and Helicobacter pylori. (C) 2009 Elsevier Ltd. All rights reserved.

The essential oils, isolated by hydrodistillation, from the flowers of different cultivars of Citrus sinensis (Cs) and Citrus clementina (Cc) collected at different harvesting times, were analyzed by GC and GC-MS. All the samples studied afforded yellowish oil, which yields ranged from 0.05 to 0.08% (v/w). The monoterpene fraction dominated both oils (66-91%), being the monoterpene hydrocarbons the main components of this fraction (45-69%). Sabinene (31-48%), linalool (15-32%) and limonene (4-10%) dominated both Cs and Cc oils. Trans-Nerolidol was the major sesquiterpene component, attaining 3-10%. Cluster analysis of the essential oil composition from the twelve samples studied confirmed a major chemical homogeneity (Scorr>0.95) despite the fact of having used different periods of hydrodistillation, different harvesting times and being flowers of two different Citrus species. INTRODUCTION Citrus is a genus of evergreen, often spiny trees and shrubs. The gland-dotted leaves are alternate and simple, usually with winged stalks and the shallowly cup-shaped, 5-petaled white fragrant flowers. The fruits in the form of hesperidium, take from five months to about one year to mature. Various species are useful, such as C. limon (lemon), C. medica (citron), C. aurantinum (sour orange), C. paradise (grapefruit), C. sinensis (sweet orange), C. reticulata (mandarin, tangerine) and C. clementina (clementine). Although much research work has been done on the Citrus fruits essential oils, much less is found on the Citrus flower oils, even though this can be of high relevance due to the importance of the Citrus floral aroma in perfumery. Previous studies on the floral aroma of C. sinensis addressed the relationship between the water status of the plant and the terpenoid emission, showing that the total terpenoid carbon emission of a flowering branch was 7.8 fold the emission of a nonflowering branch and that a considerable emission of linalool was linked to the presence of flowers (Hansen and Seufert, 1999). More recently, studies of the floral orange aroma have used solvent extracts, at 25oC, that showed linalool to be the major component of orange (52%) and tangerine (75%) flowers, followed by sabinene (27 and 11% in orange and tangerine, respectively) (Alissandrakis et al., 2003). Sabinene (35%), myrcene (19%), linalool (19%) and trans-ocimene (10%) were the main components of the solid-phase micro-extraction (SPME) of the whole flowers of Citrus deliciosa (Flamini et al., 2003). The petals seemed to contribute largely to this composition since the petals volatiles included all these compounds in high amounts, whereas the other flower parts (gynoecia, stamens and pollen) showed a quite different blend of compounds. Given the importance of Citrus flowers on orange blossom honey production and perfumery and since no previous study was made on their essential oil composition, the aim of this work was the detailed chemical characterization of the floral essential oils of Citrus species. Proc. XXVII IHC-S16 Citrus and Other Trop. & Subtrop. Fruit Crops Ed.-in-Chief: Dae-Geun Oh Acta Hort. 773, ISHS 2008 90 MATERIALS AND METHODS Plant Material Collective flower samples of Citrus sinensis and C. clementina were collected during May 2005 in Tavira and Silves (Algarve), respectively. Details of sample and distillation times are listed in Table 1. Essential Oil Isolation Procedure The essential oils of each collective sample were isolated from fresh plant material by hydrodistillation, for different periods (Table 1) using a Clevenger-type apparatus (Anonymous, 1996). Gas Chromatography GC analyses were performed using a Perkin Elmer 8700 gas chromatograph equipped with two FIDs, a data handling system and a vaporizing injector port into which two columns of different polarities were installed: a DB-1 fused-silica column (30 m×0.25 mm i.d., film thickness 0.25 μm; J & W Scientific Inc., Rancho Cordova, CA, USA) and a DB-17HT fused-silica column (30 m×0.25 mm i.d., film thickness 0.15 μm; J & W Scientific Inc.). Oven temperature was programmed, 45-175°C, at 3°C/min., subsequently at 15°C/min. up to 300°C, and then held isothermal for 10 min.; injector and detector temperatures were 280 and 290°C, respectively; carrier gas, hydrogen, adjusted to a linear velocity of 30 cm/s. Samples were injected using the split sampling technique, ratio 1:50. The percent composition of the oils was computed by the normalization method from the GC peak areas, which were calculated as mean values of two injections of each oil sample, without using response factors. Gas Chromatography-Mass Spectrometry The GC-MS unit consisted on a Perkin Elmer Autosystem XL gas chromatograph, equipped with DB-1 fused-silica column (30 m×0.25 mm i.d., film thickness 0.25 μm; J & W Scientific, Inc.), and interfaced with Perkin-Elmer Turbomass mass spectrometer (software version 4.1). Injector and oven temperatures were same as above; transfer line temperature, 280°C; ion trap temperature, 220°C; carrier gas, helium, adjusted to a linear velocity of 30 cm/s; split ratio, 1:40; ionization energy, 70 eV; ionization current, 60 μA; scan range, 40-300 μ; scan time, 1 s. The identity of the components was assigned by comparison of their retention indices, relative to C8-C17 n-alkanes, and GC-MS data with corresponding data of components of reference oils, laboratory-synthesized components and commercially available standards from a home-made library. Statistical Analysis The percentage composition of the essential oil samples was used to determine the relationship between the different samples of Citrus by cluster analysis using the NTSYSpc software (version 2.02, Exeter Software, Setauket, New York) (Rohlf, 1998). Correlation coefficient was selected as a measure of similarity among the twelve accessions, and the unweighted pair-group method with arithmetic average (UPGMA) was used for cluster definition. The degree of correlation was evaluated according to Pestana and Gageiro (2000) as: very high if correlation ranged between 0.9 and 1, high between 0.7 and 0.89, moderate between 0.4 and 0.69, low between 0.2 and 0.3 and very low if

© 2015 Taylor & Francis. The chemical composition, and antioxidant, antimicrobial and anti-proliferative activities of the essential oils of Ammoides pusilla (Apiaceae) and Thymus munbyanus (Lamiaceae), collected in Algeria, were studied. Cumin alcohol (44%), p-cymene (18%), limonene (14%), thymol (11%) and γ-terpinene (7%) predominated in A. pusilla essential oil, whereas carvacrol (71%) was dominant in T. munbyanus essential oil. The antibacterial activity of A. pusilla and T. munbyanus essential oils was studied by the agar diffusion method against Escherichia coli, Salmonella enterica serovar Thyphimurium, methicillin-resistant Staphylococcus aureus and Listeria monocytogenes. The tested bacteria were more susceptible to T. munbyanus essential oil. Ammoides pusilla essential oil was the most effective for scavenging the free radicals. Ammoides pusilla essential oil also had the best reducing power as well as the highest lipid peroxidation inhibition. Thymus munbyanus essential oil showed the best anti-proliferative activity of human acute monocytic leukemia cell line (THP-1)., The authors thank Fundação para a Ciência e Tecnologia (FCT) the financial support under the project FCT PEst-OE/EQB/LA0023/2011.

The effect of coating Arbutus unedo fresh fruit with alginate-based edible coatings enriched with the essential oils compounds (EOC) eugenol (Eug) and citral (Cit) was studied. The minimum inhibitory concentrations (MIC) against the main postharvest pathogens were determined for Eug and Cit giving values of 0.10 and 0.15 (w/v), respectively. Twelve formulations of edible coatings were used: sodium alginate (AL) was tested at 1 and 2% (w/v) with incorporation of Eug and Cit at MIC and double MIC or their combination at MIC. Arbutus berries were dipped in those solutions for 2 min, and then stored at 0.5 degrees C. Control consisted of uncoated fruit. On days 0, 14 and 28, samples were taken to perform physicochemical and biochemical analysis [color CIE (L*, h degrees), firmness, soluble solids content (SSC), weight Loss, trolox equivalent antioxidant capacity (TEAC), microbial growth and taste panels]. Results showed that edible coatings of 1% AL were the best to maintain most quality attributes of the commodity through storage at 0.5 degrees C. The incorporation of Cit and Eug into the alginate edible coatings improved the coatings in most cases, AL 1% + Eug 0.20% and AL 1% + Cit 0.15% + Eug 0.10% being those that better preserved sensory and nutritional attributes and reduced microbial spoilage. Thus, these coatings may be useful for improving postharvest quality and storage life of fresh arbutus fruit. (C) 2014 Elsevier B.V. All rights reserved.

The chemical composition of the essential oils from the leaves and the flowers of Thymus albicans Hoffm. et Link collected at three regions of Algarve, south of Portugal, was analyzed by GC and GC/MS. The oils isolated from the flowers and the leaves were obtained in similar yields, 4.3% (v/w) and 4.2% (v/w), in the samples from Quinta do Lago, and 3.5% and 3.6%, in the samples from Ancao, respectively. In contrast, the oil yields from Gambelas ranged from 5.7%, in the leaf oils, to 9.2%, in the flower oils. The oils isolated from all samples of leaves and flowers were dominated by the oxygenated monoterpene 1,8-cineole (42.1–67.9%). In the samples collected at Quinta do Lago, high levels of linalool were also found (30.3–36.9%). The major monoterpene hydrocarbons in all samples were α-pinene (1.7–4.3%), sabinene (1.6–3.4%) and (β-pinene (2.6–4.9%). The concentrations of α-pinene (1.7–1.8%), camphene (0.2%) and (β-pinene (2.6–2.9%) in the samples from Quinta do Lago were in lower amounts than in ...

The chemical composition of the essential oils from the leaves and the flowers of Thymus mastichina collected at different regions of Portugal were analyzed by GC and GC/MS. It revealed that fresh flowers produce larger amounts of oils than the leaves. The highest oil yields were obtained from the flowers collected at Arrabida (3.5%, v/w) and Mertola (3.0%, v/w). Two types of oils were differentiated according to their main components. Oils rich in 1,8-cineole whose concentrations ranged from 39.4% (in the flower oils collected at Mertola) to 69.2% (in the leaf oils from Arrabida), and an oil rich in linalool (73.5%) that was only detected in a sole plant group from Sesimbra. Camphor, borneol, terpinen-4-ol and α-terpineol appeared in relative high levels in the oils of the plants from Mertola and S. Bras de Alportel. In spite of the samples collected at Arrabida belonging to the 1,8-cineole type, camphene, (E)-β-ocimene, camphor and borneol were the compounds detected in the smallest amounts in ...

The essential oils from four samples of Teucrium lusitanicum and one sample of Teucrium algarbiensis, grown in Algarve (southern Portugal) were analyzed by gas chromatography (GC) and gas chromatography-mass spectroscopy (GC-MS). Seventy-one volatile compounds were identified. Major compounds of T. algarbiensis oil were alpha-pinene (8.3%), sabinene (7.2%), beta-pinene (10.2%), limonene (11.8%) and germacrene D (7.6%). Concerning T. lusitanicum, some quantitative differences were found with regards to the major constituents of the oils from four populations: alpha-pinene (0.8-8.5%), sabinene (2.1-9.6%), beta-pinene (2.5-11.9%), limonene (1.2-11.5%) and elemol (2.6-12.0%). (C) 2004 Elsevier B.V. All rights reserved.

The composition of essential oils isolated from Thymus albicans and Thymbra capitata collected in Algarve (Portugal), Th. mastichina collected in Algarve and Estremadura (Portugal) and Th. carnosus also collected in Algarve, during the flowering phase, was analysed by gas chromatography (GC) and GC coupled to mass spectrometry (GC-MS). The antioxidant capacity of the oils as well as some of their main components was determined by periodic evaluation of the peroxide values in sunflower oils stored at 60 degrees C. These peroxide values were compared to that of butylated hydroxytoluene (BHT) and control (without adding antioxidants) under the same experimental conditions. The oils of Th. albicans and Th. mastichina, collected in Algarve, were dominated by 1,8-cineole (68% and 45%, respectively), whereas linalool (52%) was the main component from the oils isolated from Th. mastichina collected in Estremadura. Carvacrol (68%) was the major component present in the oils of Thymbra capitata while borneol (18%), terpinen-4-ol (11%) and camphene (9%) were the major ones in the essential oil of Th. carnosus. The essential oils as well as some of their main components showed higher antioxidant capacity than that of the synthetic antioxidant BHT. At the end of the experiment (57 days), BHT showed a percentage of inhibition of 20%, while that of the essential oils ranged from 46% for Th. carnosus, to 59% for Th. mastichina collected in Estremadura.

In the present work, the aerial parts of T. mastichina, were collected over a day period, during the flowering phase. The oil was isolated both from the fresh leaves and the fresh flowers by hydrodistillation and analysed by GC and GC/MS. Significant differences were registered between the content and composition of leaf oil and that of flower oil, while changes in consequence of the day period were less emphasised. The highest oil content was obtained from the flowers (2.0 and 2.2 %) at 12 h and 17 h, respectively. The major component of the essential oils was 1,8-cineole, present in higher amounts in the leaf oils than in the flower oils. Its minimal percentages detected in the leaf and the flower oils were 50.2 % and 46.7 %, respectively, observed at 23 h, while the maximal ones were 61.0 % and 50.2 %, at 12 h. Camphor, delta-terpineol + borneol and terpinen-4-ol were also present in higher amounts in the leaf oils than in the flower oils. In both oils, elevated concentrations of delta-terpineol + borneol were detected at 23 h (9.7 % and 8.2 %, respectively). The concentration of myrcene was ten times superior in the flower oils relatively to the leaf oils. In almost all samples, elemol was the sole sesquiterpene whose concentration exceeded 1.0 %.

The aim of this study was to evaluate the adaptation response of Staphylococcus aureus, methicillin-resistant S.aureus (MRSA), and Listeria monocytogenes to the essential oil (EO), eugenol, and citral. The minimum inhibitory concentration of eugenol and citral was determined by agar dilution and microdilution. Adaptation to eugenol and citral was done by sequential exposure of the pathogens to increasing concentrations of the essential oils. The M2-A9 standard was used to determine the antibiotic susceptibility. The effect of eugenol and citral on the adherence ability was evaluated by the crystal violet assay. The impact of adaptation to eugenol on virulence was estimated using the Galleria mellonella model. No development of resistance to the components and antibiotics was observed in the adapted cells of S.aureus, MRSA, and L.monocytogenes. Eugenol and citral at subinhibitory concentration reduced the bacterial adherence. Adaptation to subinhibitory concentration of eugenol affected the virulence potential of S.aureus, MRSA, and L.monocytogenes. Eugenol and citral do not pose a risk of resistance development in a continuous mode of use. These EO components showed a high efficacy as antistaphylococcal and antilisterial biofilm agents. Adaptation at subinhibitory concentration of eugenol protected the larvae against listerial and staphylococcal infection. FCT - Fundacao para a Ciencia e Tecnologia [PEst-OE/EQB/LA0023/2013] info:eu-repo/semantics/publishedVersion

Propolis is a resinous substance collected by honeybees to seal honeycomb, which has been used in folk medicine due to its antimicrobial and antioxidant properties. In the present study, water and methanol were used to extract phenols and flavonoids from propolis collected in thirteen different areas in the Algarve region during the winter and spring. The ABTS(center dot+), DPPH center dot, and O-2(center dot-) scavenging capacity, and metal chelating activity were also evaluated in the propolis samples. Methanol was more effective than water in extracting total phenols (2.93-8.76 mg/mL) (0.93-2.81 mg/mL). Flavones and flavonols were also better extracted with methanol (1.28-2.76 mg/mL) than with water (0.031-0.019 mg/mL). The free radical scavenging activity, ABTS (IC50 = 0.006-0.036 mg/mL), DPPH (IC50 = 0.007-0.069 mg/mL) and superoxide (IC50 = 0.001-0.053 mg/mL), of the samples was also higher in methanolic extracts. The capacity for chelating metal ions was higher in aqueous extracts (41.11-82.35%) than in the methanolic ones (4.33-29.68%). Propolis from three locations of Algarve region were richer in phenols and had better capacity for scavenging free ABTS and DPPH radicals than the remaining samples. These places are part of a specific zone of Algarve known as Barrocal. Cruz Alta, Lda.; CDCTPV (Portugal); CEOT; Programa Nacional de Re-equipamento Cientifico (PNRC) - FCT (Fundacao para a Ciencia e a Tecnologia) [REEQ/601/EEI/2005]; POCI - FEDER; FCT info:eu-repo/semantics/publishedVersion

Miguel M.G., Antunes M.D., Rohaim A., Figueiredo A.C., Pedro L.G., Barroso J.G. (2014): Stability of fried olive and sunflower oils enriched with Thymbra capitata essential oil. Czech J. Food Sci., 32: 102–108. The stability of olive and sunflower oils for domestic uses after frying cow steak or only heating were evaluated in the presence or absence of the carvacrol-rich essential oil of Thymbra capitata . The treatments consisted of sunflower and olive oils either enriched with 200 mg/l of T. capitata oil or without it, heating at 180°C for 20 min, or frying 100 g cow steak at the same temperature and for the same period of time. In all assays, acid, peroxide, and p -anisidine values were followed over time. The fatty acid profile was estimated before heating or frying as well as at the end of the experiment. The results showed that the type of fat as well as the type of treatment (frying or heating) was de terminant for the acid, peroxide, and p -anisidine values found. The presence of the essential oil also demonstrated to affect those values depending on the type of the oil as well as on the type of the treatment (frying or heating). In contrast, the fatty acid profile did not change greatly.