976 resultados para Oregano extracts
Resumo:
Currently, many consumers search for food with functional characteristics beyond their nutritional properties. Thus, the concept of functional food becomes a hot topic, allowing the obtaining of health benefits, including disease prevention. In this context, plants are recognized as sources of a wide range of bioactives, mainly phenolic compounds. In particular, the Rosmarinus officina/is L., commonly referred as rosemary, has several phenolic compounds with different bioactive properties such as antioxidant, antiinflammatory and antimicrobial activities, among others [!]. Hence, this plant has great potential for incorporation into foods in order to confer bioactivity to the final products. However, it should be highlighted that the bioactive compounds if exposed to adverse environments, for example: light, moisture, extreme pH, storage, food processing conditions, can be degraded leading to the consequent loss of bioactivity [2]. The microencapsulation is an alternative to overcome this problematic of bioactive compounds, as also to ensure controlled release, or target deliver to a specific site [3]. In this work, lyophilized rosemary aqueous extract prepared by in:'usion was used as a functional ingredient for cottage cheeses, after proving that it possesses, both higher content in phenolic compounds and higher antioxidant activity, comparatively with the corresponding hydroethanolic extract. The rosemary aqueous extract revealed, for example, a DPPH scavenging activity with an EC50 value of 73.44±0.54j!g/mL and presented as main phenolic compound the caffeic acid dimer, commonly named as rosmarinic acid. For the functionalized cottage cheeses, a decrease of bioactivity was observed after seven days under storage in fridge, when the extracts were incorporated in its free form. Therefore, to preserve the antioxidant activity, the rosemary aqueous extract was efficiently microencapsulated by using an atomization/coagulation technique and alginate as the matrix material and thereafter incorporated into the cottage cheeses. The final microspheres showed a size, estimated by OM using a magnification of I OOx, ranging between 51.1 and 122.6 J!m and an encapsulation efficiency, estimated through an indirect method, approaching 100%. Overall, the introduction of both free and microencapsulated extracts did not change the nutritional value of cottage cheeses, providing bioactivity that was more preserved with microencapsulated extracts putting in evidence the importance of using microencapsulation to develop effective functional foods.
Resumo:
Angiogenesis is a biological process through which there is the formation of new blood vessels from preexisting ones [I]. However, in pathological cases, the abnormal growth of new blood vessels promotes the development of various diseases including cancer [2) through the production of atypically large amounts of angiogenesis factors, e.g. the vascular endothelial growth factor (VEGF) [3]. The plant secondary metabolites have been the subject of several studies to evaluate their benefits to human health. In particular, the phenolic compounds have high potential for use in the food industry, including the development of functional foods. Among these, apigenin has been associated with chemopreventive effects related to cancer [4]. In fact, chemoprevention is a present-day concept and contemplates the use of medicines, biological compounds or nutrients as an intervention strategy of cancer prevention. In this work, an Arenaria montana L hydroethanolic extract was prepared and after characterization by HPLC-DAD-ESI/MS showed to be rich in apigenin derivatives. Furthermore, it exhibited ability to inhibit the phosphorylation of VEGFR-2 (vascular endothelium growth factor receptor) through an enzymatic assay. However, for the major protection of bioactive compounds, the extract was microencapsulated by an atomization/coagulation technique with alginate as the matrix material. Posteriorly, the hydroethanolic extract, in free and microencapsulated forms, was incorporated in yogurts in order to develop a novel chemopreventer food in relation to the angiogenesis process. The functionalized yogurts with A. montana extracts (free and microencapsulated) showed a nutritional value similar to the used control (yogurt without extract); however, the samples enriched with extracts revealed added-value regarding the VEGFR-2 phosphorylation inhibition ability. This effect was more effectively preserved over time in the samples functionalized with the protected extract. Overall, this work contributes to the valorization of plants rich in flavonoids, exploring its antiangiogenic potential with VEGFR-2 as target. Moreover, the atomization/coagulation technique allowed the production of viable microspheres enriched with the plant extract. The microspheres were effectively incorporated into yogurts, protecting the extract thus envisaging the development of novel functional foods with chemopreventive effects.
Resumo:
Foeniculum vulgare Mill. (fennel) and Matricaria recutita L. (chamomile) are two examples of plants with reported antioxidant and antimicrobial properties, which can be related with their composition in phenolic compounds [1,2]. Furthermore, according to previous results of our research group, the direct incorporation of the aqueous extracts showed capacity to maintain the nutritional properties of the cottage cheeses, up to 7 days of storage, while improving the antioxidant potential. However, after 14 days, a decrease in the antioxidant properties was observed [1,2], which can be related with factors such as light, moisture, temperature and pH, that can cause bioactive compounds degradation. Therefore, the aim of the present study was to prepare microcapsules with the aqueous extracts of fennel and chamomile for incorporation in cottage cheese samples, in order to protect the bioactive molecules present in the extracts, such as phenolic compounds, and prevent the decrease of the antioxidant activity observed after the 14 days period. The microspheres were prepared using an atomization/coagulation technique. Sodium alginate was used as the matrix material to produce the microspheres that were characterized through optical microscopy (OM), during and after atomization, for inspecting morphology. The encapsulation efficiency (EE) was determined by HPLC-DAD by an indirect method by analysing the coagulation solution. FTIR was also used to attest the presence of the extract inside of the alginate matrix. These microencapsulated extracts were incorporated in cottage cheese samples that were further characterized in terms of nutritional properties and antioxidant potential right after incorporation, and after 7 and 14 days of storage at 4•c. The EE was estimated as -100% and the FTIR analysis confirmed the presence of the extracts inside the microspheres. The results showed that the incorporation of the microencapsulated extracts did not cause changes in the nutritional value of cottage cheeses (through a comparison with control samples without extracts). The predominant fatty acids were palmitic (C16:0) and oleic (CI8:0) acids. The order of abundance of fatty acids was as follows: saturated fatty acids (SF A)> monounsaturatcd fatty acids (MUF A)> polyunsaturated fatty acids (PUF A). Regarding free sugars, lactose was the only sugar identified and quantified in all samples. Regarding the antioxidant activity, the samples functionalized with the microencapsulated extracts showed a higher preservation of this property even after the 7th day of storage. Overall, the incorporation of the protected plant extracts in dairy foods can be a strategy to provide health benefits to consumers.
Resumo:
Synthetic additives used in a wide variety of food products have been associated to some toxic effects. This conducted to an increasing interest of consumers for natural additives, including food preservers [1]. Many aromatic herbs have been used to prepare bioactive extracts with benefits to the consumer's health. Foeniculum vulgare Mill. (fennel) and Matricaria recutita L. (chamomile) are examples of popular herbs rich in phenolic compounds with documented antioxidant and antimicrobial properties [2,3]. The present work confirms the antioxidant (DPPH scavenging activity, reducing power and lipid peroxidation inhibition) and antimicrobial (against bacteria such as Bacillus cereus and Salmonella Typhimurium and fungi such as Aspergillus niger, A. versicolor and PenicilliumfimicuJosum) activities of fennel and chamomile extracts, obtained by decoction. The chemical characterization of the extracts, performed by HPLC-DAD-ESIIMS, revealed the presence of five flavonoids (mainly qercetin-3-0- glucoside) and twelve phenolic acids (mainly 5-0-caffeolyquinic acid) for fennel extract and the presence of nine flavonoids (mainly luteolin-0-glucuronide) and ten phenolic acids (mainly di-caffeoyl-2,7- anhydro-3-deoxy-2-octulopyranosonic acid) for chamomile extract. Due to their high antioxidant and antimicrobial activities, both extracts were then incorporated (at DPPH scavenging activity EC25 value: 0.35 mg/mL and 0.165 mg/mL for fennel and chamomile, respectively) in cottage cheeses (prepared by Queijos Casa Matias Lda) as natural additives with two objectives: to increase the shelf-life of the cottage cheeses and to provide bioactive properties to the final products. The results showed that the use of these natural extracts did not alter significantly the nutritional characteristics of the cottage cheese in comparison with control samples (cottage cheese without extracts), but improved its antioxidant potential (more evident in the samples with chamomile extract). After 14 days of storage, only the control samples showed signs of degradation. Overall, the present study highlights the preservation potential of fennel and chamomile extracts in cottage cheeses, improving also their bioactivity.
Resumo:
Aging process is conceived as a normal stage during human life cycle, but it is also considered a hot topic among scientists and medical community. Alarming rates of premature aging and oxidative stress-related diseases have increasingly affect human individuals. Stress, pollution and exposition to chemical substances are considered the main triggering factors for those conditions; in addition, they also suppress the immune system and, therefore, improve organic vulnerability and occurrence of opportunistic infections [I]. Apart from the associated morbidity and mortality, the increasing rates of antimicrobial resistance improve the severity of the clinical conditions [2]. Botanical preparations possess a multitude of bioactive properties, namely acting as antimicrobials, antioxidants, and homeostasis modulators. Thus, upcoming alternatives, mainly based in plant phytochemicals, are necessary to improve the wellbeing as also life expectancy of individuals. The present study aims to evaluate and to compare both antioxidant and antimicrobial properties of plant extracts rich in phenolic compounds. Among the tested plants, Glycyrrhiza glabra L. (licorice) evidenced the most pronounced free radicals scavenging and antimicrobial effects, followed by Salvia officina/is L. (sage), Thymus vulgaris L. (thyme) and Origanum vulgare L. (oregano). Eucalyptus globulus Labill. (blue gum) and Juglans regia L. (walnut) also showed a high effect, while Pterospartum tridentatum (L.) Willk. (carqueja) and Rubus ulmifolius Schott (elm leaf blackberry) displayed moderate effects, and lastly, Tabebuia impetigirwsa (Mart. ex DC) Standley (pau d'arco), Foeniculum vulgare Miller (fennel), Rosa canina L. (rose hips) and Matricaria recutita L. (chamomile) gave only slight effects. In general, the most pronounced bioactivities were observed in the plant preparations (infusion>decoction>hydromethanolic extract) with higher levels of phenolic compounds (both flavonoids and phenolic acids). The observed synergisms between the phenolic compounds present in the extracts highlight the use of phytochemicals as future health promoters. However, further studies are necessary to understand the effective mode of action of individual phenolic constituents as also the existence of polyvalence relationships between them.
Resumo:
Irradiation is a methodology qualified for dry ingredients preservation or decontamination and can be performed using various radiation sources and energy levels in accordance with the objectives to be achieved [1]. Electron beam irradiation is used mainly for food products with low density, while gamma irradiation is mainly used for large volumes [2]. Arenaria Montana L. has a high antioxidant potential and richness in bioactive phytochemicals. It is used in Portuguese traditional medicine, acting therapeutically as an anti-inflammatory and diuretic plant [3]. The aim of this work was to evaluate the effects of gamma and electron beam irradiation at different doses (I and 10 kGy) in the antioxidant activity of A. montana. Free radicals scavenging activity, reducing power and lipid peroxidation inhibition properties of its methanolic extracts and infusions were evaluated. Through a global analysis, it was concluded that the antioxidant activity proved to be higher in methanolic extracts in comparison with the infusions, where it decreased with increasing irradiation dose regardless of the technology used (gamma or electron beam). For methanolic extracts, electron beam resulted in increased antioxidant activity while gamma irradiation caused a decrease in these extracts. Thus, the antioxidant potential is variable depending not only on the type of radiation and the dose applied, but also on the solvent used in the preparation of the extracts (methanol or water).
Resumo:
Mushrooms are rich in several bioactive metabolites among them are phenolic compounds, terpenoids, polysaccharides, lectins, and steroids including mycosterols, namely ergosterol [1]. Ethanolic extracts prepared by maceration of several mushroom species have been recently described as having antiinflammatory properties [2]. In the present work, ethanolic extracts of Agaricus bisporus L., Lentinus edodes (Berk.) Pegler and Pleurotus ostreatus (Jacq. ex Fr.) P.Kumm., purchased from a local supermarket in the Northeast of Portugal, were obtained by Soxhlet and chemically characterized in terms of ergosterol content by HPLC-UV. The antioxidant properties of these extracts were evaluated through DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging activity (RSA), reducing power (RP), p. carotene bleaching inhibition (CBI) and lipid peroxidation inhibition in TBARS (thiobarbituric acid reactive substances) assay (LPI); the antioxidant activity of ergosterol was also evaluated by the DPPH assay. The anti-inflammatory activity of the same extracts and ergosterol was evaluated in LPS (lipopolysaccharide) stimulated RAW 264.7 macrophages, through the inhibition of NO production. A. bisporus revealed the highest content in ergosterol (44.8 ± 0.4 mg/ g extract) followed by P. ostreatus (34 ± 3 mg/ g extract) and finally L. edodes (8.9 ± 0.1 mg/ g extract). A. bisporus showed the highest RSA, RP and CBI (EC50 values= 7.0 ± 0.8, 2.3 ± 0.1 and 1.4 ± 0.1 mg/mL, respectively), while L. edodes presented the highest LPI (2.5 ± 0.1 mg/mL ); ergosterol revealed higher RSA (0.46±0. 0 I mg/mL) than the extracts. Concerning the anti-inflammatory potential, the most efficient species was L. edodes (lC50 value = 164 ± 16 J.lg/mL), followed by A. bisporus (185 ± 16 J.lg/mL) and finally P. ostreatus (290 ± 10 J.lg/mL). However, ergosterol presented lower activity (338 ± 23 J.lg/mL) due to its low solubility in the culture medium. The higher antioxidant properties displayed by A. bisporus can be related with its higher ergosterol content, while in the anti-inflammatory activity this relation cannot be established also due to the low solubility of ergosterol in the cells culture medium, decreasing the ergosterol availability. More studies are being conducted regarding the ergosterol solubility. Several compounds have been implicated in the bioactivity of mushrooms and in this study we have found that ergosterol can give an important contribution.
Resumo:
The cercospora leaf spot, caused by Cercospora abelmoschi Ellis and Everhart, is quite common in okra culture. Therefore, this study aimed to evaluate the efficiency of aqueous extracts of neem ( Azadirachta indica A. Juss), citronella ( Cymbopogon nardus (L.) Rendle), eucalyptus ( Eucalyptus grandis L.), ecolife®, A. indica oil and fungicide cercobin 700 PM® in control of cercospora leaf spot on okra in greenhouse. The extracts and neem oil were tested in concentration 10%, the fungicide cercobin 700PM® in dose 2.5 g.l-1, applied 10 days after pathogen inoculation by leaf spray and the citric biomass extract ecolife® in concentration 5.0 ml.l-1, applied 10 days before pathogen inoculation. All treatments, except ecolife®, were effective in controlling cercospora leaf spot and may be recommended as alternatives in agroecological systems.
Resumo:
Phytochemical analyses as well as antimicrobial and antioxidant activities of the extracts of C. sumatrensis aerial parts were investigated in this study. METHODS: The aerial parts of C. sumatrensis were air dried, weighed and exhaustively extracted with hexane, ethyl acetate and methanol successively. The crude extracts were screened for metabolites. These extracts of the plant were evaluated for antimicrobial and antioxidant activities using agar diffusion and DPPH method respectively. The extracts were also analysed using Gas chromatography – Mass spectrometry, and the chromatogram coupled with mass spectra of the compounds were matched with a standard library. RESULTS: Preliminary phytochemical investigation of crude n-hexane, ethyl acetate and methanol extracts of the aerial parts of Conyza sumatrensis revealed the presence of anthraquinones, flavonoids, terpenoids, phenolics, tannin, glycosides and carbohydrate. All the crude extracts gave a clear zone of inhibition against the growth of the test bacteria ( Staphylococcus aureus , Escherichia coli , Bacillus subtilis , Pseudomona aeruginosa, Salmonella typhi , Klebsiellae pneumonae ) at moderate to high concentrations, as well as test fungi ( Candida albicans , Aspergillus niger , penicillium notatum and Rhizopus stolonifer ) at high concentration. Methanolic extract exhibited significant radical scavenging property with IC50 of 17.08 μg/mL while n-hexane and ethyl acetate extracts showed no significant antioxidant activity. GC-MS of N-hexane extract showed a total number of eleven chemical constituents with α-Farnesene and spathulenol being the most abundance compounds constituting 20.27 and 22.28% of the extract respectively. Ethyl acetate extract revealed thirteen compounds with two most abundant compounds, cis-β-farnesene (16.64 %) and cis-pinane (21.09 %). While methanolic extract affords seventeen compounds with Ephytol being the most abundant compound (19.36 %).
Resumo:
The present study aimed to characterize the extracts prepared from Pimpinella anisum L. (anise) and Coriandrum sativum L. (coriander) (Apiaceae plants) seeds in terms of phenolic composition, and to correlate the obtained profiles with the antioxidant activity. Anise gave the highest abundance in phenolic compounds (42.09± 0.11 mg/g extract), mainly flavonoids (28.08±0.17 mg/g extract) and phenolic acids (14.01±0.06 mg/g extract), and also the highest antioxidant potential, measured by the ability to inhibit lipid peroxidation and β-carotene bleaching, the reducing power and the free radical scavenging activity. Apigenin and luteolin derivatives, as also caffeoylquinic acid derivatives seem to be directly related with the higher in vitro antioxidant potential of the anise extract. In contrast, the lower antioxidant potential of coriander seems to be due to its lower abundance in phenolic compounds (2.24±0.01 mg/g extract). Further studies are necessary to evaluate the in vivo antioxidant potential of the tested extracts, but the in vitro experiments already performed highlight them as potential health promoters.
Resumo:
Globally, there is a trend for healthy food products, preferably incorporating natural bioactive ingredients, replacing synthetic additives. From previous screening studies, extracts of Foeniculum vulgare Mill. (fennel) and Matricaria recutita L. (chamomile) maintained nutritional properties and improved the antioxidant activity of cottage cheese. Nevertheless, this effect was limited to 7 days. Accordingly, aqueous extracts of these plants were microencapsulated in alginate and incorporated into cottage cheese to achieve an extended bioactivity. Plain cottage cheese, and cheese functionalized by direct addition of free decoctions, were prepared and compared. Independently of plant species, "functionalization type" factor did not show a significant effect on the nutritional parameters, as also confirmed in the linear discriminant analysis, where these parameters were not selected as discriminating variables. Furthermore, samples functionalized with microencapsulated extracts showed higher antioxidant activity after the 7th day, thereby demonstrating that the main purpose of this experimental work was achieved.
Resumo:
The in vitro anti-fungal activity of leaf and stem bark of Daniella oliveri Rolfe was investigated against selected yeasts and moulds including dermatophytes. Water and methanol were used to extract the powdered leaf and stem bark using cold infusion. Antimicrobial activity was assessed by agar-well diffusion. Phytochemical analysis was carried out using standard procedures. The plant extracts were active against the test organisms at concentrations ranging from 3.125-100 mg/mL. The methanol extracts were more active than the aqueous extracts with the highest inhibition against the yeasts, Candida albicans and Candida krusei (MIC values of 3.125 mg/mL and 6.25 mg/mL respectively). Epidermophyton floccosum and Trichophyton interdigitale were the least inhibited of all the fungal strains. Phytochemical screening revealed the presence of tannins, anthraquinones, flavonoids, cardiac glycosides, alkaloids and saponins. The anti-fungal activity of Daniella oliveri as shown in this study indicates that the plant has the potential of utilisation in the development of chemotherapeutic agents for the treatment of relevant fungal infections.
Resumo:
Angiogenesis is a process by which new blood vessels are formed from the pre-existing vasculature, and it is a key process that leads to tumour development. Some studies have recognized phenolic compounds as chemopreventive agents; flavonoids, in particular, seem to suppress the growth of tumor cells modifying the cell cycle. Herein, the antiangiogenic activity of Roman chamomile (Chamaemelum nobile L.) extracts (methanolic extract and infusion) and the main phenolic compounds present (apigenin, apigenin-7-O-glucoside, caffeic acid, chlorogenic acid, luteolin, and luteolin-7-O-glucoside) was evaluated through enzymatic assays using the tyrosine kinase intracellular domain of the Vascular Endothelium Growth Factor Receptor-2 (VEGFR-2), which is a transmembrane receptor expressed fundamentally in endothelial cells involved in angiogenesis, and molecular modelling studies. The methanolic extract showed a lower IC50 value (concentration that provided 50% of VEGFR-2 inhibition) than the infusion, 269 and 301 μg mL(-1), respectively. Regarding phenolic compounds, luteolin and apigenin showed the highest capacity to inhibit the phosphorylation of VEGFR-2, leading us to believe that these compounds are involved in the activity revealed by the methanolic extract.
Resumo:
Background: In the recent years natural resources are being in focus due to their great potential to be exploited in the discovery/development of novel bioactive compounds and, among them, mushrooms can be highlighted as alternative sources of anti-inflammatory agents. Scope and approach: The present review reports the anti-inflammatory activity of mushroom extracts and of their bioactive metabolites involved in this bioactive action. Additionally the most common assays used to evaluate mushrooms anti-inflammatory activity were also reviewed, including in vitro studies in cell lines, as well as in animal models in vivo. Key findings and conclusions: The anti-inflammatory compounds identified in mushrooms include polysaccharides, terpenes, phenolic acids, steroids, fatty acids and other metabolites. Among them, polysaccharides, terpenoids and phenolic compounds seem to be the most important contributors to the anti-inflammatory activity of mushrooms as demonstrated by numerous studies. However, clinical trials need to be conducted in order to confirm the effectiveness of some of these mushroom compounds namely, inhibitors of NF-κB pathway and of cyclooxygenase related with the expression of many inflammatory mediators.
Resumo:
Fungi of the genus Paracoccidioides are responsible for paracoccidioidomycosis. The occurrence of drug toxicity and relapse in this disease justify the development of new antifungal agents. Compounds extracted from fungal extract have showing antifungal activity. Extracts of 78 fungi isolated from rocks of the Atacama Desert were tested in a microdilution assay against Paracoccidioides brasiliensis Pb18. Approximately 18% (5) of the extracts showed minimum inhibitory concentration (MIC) values ≤ 125.0 μg/mL. Among these, extract from the fungus UFMGCB 8030 demonstrated the best results, with an MIC of 15.6 μg/mL. This isolate was identified as Aspergillus felis (by macro and micromorphologies, and internal transcribed spacer, β-tubulin, and ribosomal polymerase II gene analyses) and was grown in five different culture media and extracted with various solvents to optimise its antifungal activity. Potato dextrose agar culture and dichloromethane extraction resulted in an MIC of 1.9 μg/mL against P. brasiliensis and did not show cytotoxicity at the concentrations tested in normal mammalian cell (Vero). This extract was subjected to bioassay-guided fractionation using analytical C18RP-high-performance liquid chromatography (HPLC) and an antifungal assay using P. brasiliensis. Analysis of the active fractions by HPLC-high resolution mass spectrometry allowed us to identify the antifungal agents present in the A. felis extracts cytochalasins. These results reveal the potential of A. felis as a producer of bioactive compounds with antifungal activity.