CIMO - Posters em Encontros Científicos Internacionais
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- Characterization of phenols in salvia elegans and salvia greggiiPublication . Pereira, Olívia R.; Afonso, Andrea Luísa Fernandes; Silva, Joana de A.; Sobral, Abílio J.F.N.; Cardoso, Susana M.Although Salvia elegans and Salvia greggii are commonly used in traditional medicine in North America their main bioactive components remain unknown. The present study aims to identify the main phenolic components of these two plants. Aqueous extracts of both species were prepared according to the procedure described by Ferreira et al and the total phenolic content of the extracts was evaluated through an adaptation of the Folin-Ciocalteu method. Identification of the phenolic compounds was accomplished by reversed-phase HPLC with DAD and ESI-MSn analysis in negative mode. The aqueous extracts of S. elegans and S. greggii contained 201±46 and 136±1 μg GAE/mg of extract, respectively. The two extracts were mainly composed of rosmarinic acid, which is typically found in Salvia plants. S. elegans also contained significant amounts of other caffeic acid derivatives, in particular lithospermic acid and luteolin derivatives. S. greggii extract, contain also luteolin and apigenin derivatives. The main phenolic constituents of S. elegans and S. greggii are here described for the first time. This knowledge may help further understanding of the claimed health-benefits for these two plants.
- Development of a cosmetic anti-aging gel formulation with extracts of spontaneous plants and cultivars of Humulus lupulus L.Publication . Santos, Briolanja; Pereira, Olívia R.; Afonso, Andrea Luísa Fernandes; Pedro, Luís G.; Cardoso, Susana M.; Sousa, Maria JoãoHop (Humulus lupulus L.) is known worldwide as an essential flavor in the beer industry. Its major compounds have been demonstrated to be associated to health benefits, due to its antimicrobial, antioxidant, anti-inflammatory and anticancer activities [1]. This study intended to develop and to evaluate the stability of an anti-aging cosmetic gel by incorporation of different percentages of hydroalcoholic extracts obtained from cones (flowers) and vegetative parts (leaves) of hop spontaneous and of the Cascade and Polaris cultivars and essential oil of Thymus zygis. In addition, the phytochemical profile and antimicrobial activities determination of hop extracts and of essential oil of thymus were performed. A methylcellulose gel formulation was used as base to develop the hop cosmetic product. Subsequently, several parameters were evaluated to address its physical-chemical stability. In addition to that, the phenolic profile of hop extracts was determined by UHPLC-DAD-ESI-MS2 [2] while the composition of thyme essential oil was done by GC and GC-MS. The ability to inhibit the microbial growth was performed by microdilution broth method and the diffusion in agar test. Contrary to hop extracts, thyme oil has shown to exert antibacterial and antifungal activities and thus, it was added to the formulation as preservative. Carvacrol, terpinen-4-ol and p-cimene, determined as major compounds in this oil, could be important contributors for these activities. The extracts obtained from hop cones were rich in phenolic compounds such as cohumulone, humulone and xanthohumol, which have been claimed as possessing anti-wrinkle effect [3]. Concerning stability of the formulations, no phase separation was observed in the centrifugation, mechanical vibration tests or the color tests. However, changes were observed in the UV-Visible spectra between 300nm to 350nm wavelengths, probably by presence of the phenolic compounds such as example xanthohumol, cohumulona, humulona and lupulona [3]. In texture by back extrusion, only the formulation with the extracts of the Polaris variety has high consistency and low viscosity. In the light test there was phase separation in the samples due to the occurrence of dehydration, to minimize this effect, it must be properly in a non-transparent packaging to protect from light. Overall, the incorporation of hydroalcoholic extracts of hop and essential oil of thyme in methylcellulose gel formulations, especially with Polaris variety with 2.5% hydroalcoholic extract of hop cones, allow to obtained a stable cosmetic with potential as anti-aging take into account the chemical composition.
- Phenolic composition of four sage species: salvia farinacea, salvia mexico, salvia greggii and salvia officinalisPublication . Pereira, Olívia R.; Afonso, Andrea Luísa Fernandes; Cardoso, Susana M.Salvia species are used worldwide for medicine purposes. In general, these medicinal plants have high amounts of flavonoids and phenolic acids, that are thought to be closely related to their health properties [1,2]. In this work, the aerial parts of Salvia farinacea, Salvia mexico, Salvia greggii and Salvia officinalis were extracted with hot water [3]. Extracts were evaluated for their total phenolic content by an adaptation of the Folin-Ciocalteu method and further analysed by high performance liquid chromatography associated with electrospray mass spectrometry (HPLC-DAD-ESI-MSn) in the negative ion mode [4], in order to identify their individual phenolic constituents. The aqueous extracts of S. farinacea, S. mexico, S. officinalis and S. greggii contained, respectively, 106±13, 159±38, 175±46 and 136±1 μg GAE/mg of total phenolics. These four species were characterized by a clear prevalence of caffeic acid derivatives, in particular of rosmarinic acid (MW 360), that is generally the most abundant phenolic compound in Salvia species [2,3]. In addition, S. mexico and S. officinalis contained moderate amounts of salvianolic acid B (MW 718). Among these two, S. mexico was richer in O-caffeoylquinic acid (MW 354), while the latter presented high amounts of salvianolic acid K (MW 556) and moderate amounts of its structural isomer. All the extracts were enriched in flavones: S. farinacea and S. officinalis contained high amounts of luteolin-O-glucuronide while S. mexico contained luteolin-C-glucoside with respective characteristic mass spectrometry fragmentation pattern m/z at 461→285 and m/z at 447→357, 327. Similarly, S. greggii extract presented high content of luteolin-7-O-glucoside ([M-H]− at m/z 447→ 285) and luteolin-C-glucoside and moderate quantities of apigenin-C-hexoside ([M-H]− at m/z 431→341, 311). Further studies are being undertaken in order to understand the contribution of these phenolic constituents in the biological activities of Salvia plants.
- Phenolic compounds and antioxidant capacity of three thymus species plantsPublication . Afonso, Andrea Luísa Fernandes; Pereira, Olívia R.; Cardoso, Susana M.Thymus plants comprise distinct species with claimed health properties [1], commonly associated to their essential oils and phenolic compounds. Albeit that, the phenolic composition and the biological activities of many Thymus species remain unclear. This work aimed to elucidate the phenolic composition and antioxidant properties of aqueous extracts from Thymus herba barona, Thymus caespetitus and Thymus fragrantissimus. The aqueous extracts of the three Thymus species were evaluated for their total phenolic compounds by an adaptation of the Folin-Ciocalteu method [2], and individual phenolic compounds were identified by high performance liquid chromatography associated with electrospray mass spectrometry (HPLC-DAD-ESI-MSn) in the negative mode. The antioxidant activity of each extract was carried out by DPPH● scavenging assay and ferric reducing antioxidant power assays [3]. Total phenolic compounds in the three extracts ranged from 236±27 (T. caespetitus) to 273±17 μg GAE/mg (T. fragrantissimus). Similarly to other Thymus species [1,4], these extracts were rich in caffeic acid derivatives (characteristic UV spectra maxima at 290 and 328 nm) and mainly composed of rosmarinic acid (MW 360). Other caffeic acid derivatives included salvianolic acid K (MW 556) and 3′-O-(8″-Z-caffeoyl)rosmarinic acid (MW 538). High amounts of the flavone luteolin-O-glucuronide ([M-H]− at m/z 461→285) were found in T. caespetitus while the others species contained moderate amounts of this compound. T. herba barona, T. caespetitus and T. fragrantissimus extracts showed high DPPH radical scavenge ability (EC50 values 11.6±0.9, 13.8±0.6 and 10.9±1.2 μg/mL respectively), as well as high reducing power (EC50 values of 35.1±4.5, 39.3±2.7 and 32.4±4.3 μg/mL, respectively), that were comparable to those of reference compounds. This work is an important contribution for the phytochemical characterization and the antioxidant capacity of these three Thymus species.
- Salvia elegans: uma fonte natural de compostos antioxidantesPublication . Pereira, Olívia R.; Afonso, Andrea Luísa Fernandes; Silva, Joana de A.; Batista, Ana Rita; Sobral, Abílio J.F.N.; Cardoso, Susana M.A espécie Salvia elegans é um arbusto que pertence ao género Salvia, família das Lamiaceae. Várias espécies do mesmo género têm vindo a ser cultivadas para uso na culinária e em medicina tradicional [1]. Devido ao seu cheiro característico, a S. elegans é vulgarmente conhecida por salva ananás e utilizada como condimento ou aromatizante em alimentos. No México esta espécie é popularmente conhecida como “mirto” e tem sido usada na medicina tradicional para tratar afeções do sistema nervoso central [2, 3]. Apesar disso, as suas propriedades biológicas não estão ainda estudadas. Neste trabalho pretende-se clarificar a capacidade antioxidante da espécie S. elegans, bem como proceder à identificação dos seus principais constituintes fenólicos, uma vez que vulgarmente estes compostos se encontram associados a esta propriedade [4]. Para tal, as partes aéreas da planta S. elegans foram extraídas com água quente [5] e o teor de compostos fenólicos totais no extrato foi determinado por uma adaptação do método colorimétrico de Folin-Ciocalteu [6]. A identificação dos compostos fenólicos foi efetuada por análise de cromatografia líquida de alta resolução (HPLC-DAD), acoplada à técnica de espectrometria de massa com ionização por electrospray (ESI-MSn), em modo negativo. Ainda, a capacidade antioxidante do extrato aquoso de S. elegans foi testada através dos testes de captação de radicais livres DPPH•, e do teste do poder redutor. De acordo com o método de Folin-Ciocalteu, os compostos fenólicos no extrato aquoso de S. elegans totalizam 201±46 μg EAG/ mg de extrato. O extrato é particularmente rico em ácido rosmarínico e contém ainda quantidades moderadas de outros derivados do ácido cafeico. Para além disto, o extrato de S. elegans possui uma boa capacidade antioxidante demonstrada pelos métodos de DPPH• e poder redutor. Os resultados obtidos neste estudo permitem sugerir que S. elegans possui grande potencial para ser aplicada como agente antioxidante. Futuramente, pretende-se esclarecer a contribuição individual dos principais constituintes fenólicos do extrato de S. elegans na atividade antioxidante do mesmo.
- Thymus zygis and thymus pulegioides as a source of phenolic compoundsPublication . Pereira, Olívia R.; Afonso, Andrea Luísa Fernandes; Domingues, Vasco; Cardoso, Susana M.Thymus is an important genus in the West Mediterranean region, where many species are cultivated for confection of several dishes, including salads, soups, stews and sauces. Many Thymus, including T. zygis and T. pulegioides are also commonly used in traditional medicine [1]. Whist phenolic compounds are commonly associated to health-beneficial properties of Thymus, the specific phenolic composition of T. zygis and T. pulegioides is presently unknown [2]. The extracts of the aerial parts of T. zygis and T. pulegioides species were prepared with hot water as previously described [3]. Total phenolic contents were determined according to the adapted Folin-Ciocalteu colorimetric method [4] and the identification of the phenolic compounds was performed by high performance liquid chromatography (HPLC-DAD). The extracts of T. zygis and T. pulegioides contained 319±44 and 391±3 μg GAE/mg, respectively. Likewise other Thymus species [2], both extracts were enriched in caffeic acid derivatives, showing characteristic UV spectra maxima at 290 and 328 nm. The latter included rosmarinic acid (MW 360) and 3′-O-(8″-Z-caffeoyl)rosmarinic acid (MW 538) [2]. The two extracts also contained moderate amounts of the flavone luteolin-7-O-glucoside (MW 448) that has been previously described in others Thymus species [2]. Yet, T. zygis and T. pulegioides phenolic profiles could be clearly distinguished: while the first had high levels of the phenolic acid salvianolic acid K (MW 556; UV spectra maxima at 288, 322), the extract of T. pulegioides was enriched in eriodictyol-O-hexoside and derivatives, with typical UV spectra maxima at 283 nm. Note that salvianolic acid K has been previously described in T. vulgaris while eriodictyol-O-hexoside derivatives were previously found in T. vulgaris and T. serpyllum [2]. The phenolic compounds of T. zygis and T. pulegioides are here described for the first time.
- Utilization of bee products on the development of cosmetic formulation with terpenes preservatives from Trás-os-Montes aromatic plantsPublication . Jelidi, Sarra; Pereira, Olívia R.; Afonso, Andrea Luísa Fernandes; Pedro, Luís G.; Cardoso, Susana M.; Sousa, Maria JoãoThe use of natural cosmetics is nowadays becoming increasingly frequent given to the notice of consumers to the consequences of using chemically synthesized compounds, which may even be carcinogenic. This work aimed to develop a cream formulation for daily moisturizing of the skin, with natural ingredients, like bee products, plants of the region of Trás-Os-Montes and vegetable oils. Among bee products, beeswax was chosen for its properties, like skin repairing power and antimicrobial power. In more detail, two sage plants (Salvia officinalis and Salvia elegans) and the thyme species Thymus zygis subsp. zygis were used as sources of antioxidants. The phenolic profile of the hydroalcoholic extracts of sage were elucidated by UHPLC-DAD-ESI-MS2 analysis, while the composition of the essential oil of T. zygis subsp. zygis was determined by GC/ GC-MS. The antimicrobial activities were evaluated by microdilution broth method and by diffusion agar test. The obtained formulations were subjected to physicochemical and microbiological stability tests. The major phenolic components of S. officinalis extract were rosmarinic acid, apigenin-Oglucuronide, scutellarein-O-glucuronide and luteolin-7-O-glucuronide while S. elegans was mostly composed by rosmarinic acid, salvianolic acid K, luteolin-7-O-glucuronide and caffeic acid. The GC/ GC-MS analysis of essential oil of T. zygis subsp. zygis was mainly composed of carvacrol, cymene and trans-sabinene hydrate. The formulations had pH values slightly acid, similar to the skin pH. No phase separation or alteration of the organoleptic criteria of the formulations were observed. The stability of the products was also verified by spectrophotometer within the UV visible region between 210 and 600 nm, especially the sample containing olive oil and 5% of S. elegans hydroalcoholic extract. A non- Newtonien behavior, criterion sought in cosmetic creams, was also observed during the analysis by the texturometer. Additionally, the thyme volatile oil, used as a preservative in the cream, showed an inhibitory effect against Staphylococcus aureus (MIC and MBC < 0.031%), Pseudomonas sp (MIC and MBC = 1.25%), Escherichia coli (MIC and MBC = 0.31%) and Candida albicans. Above a degree of 0.31%, thyme oil showed in C. albicans, inhibition zones varying from 2 to 9.5 mm against C. albicans, in the agar diffusion test. The promising results of these work allows propose beeswax, S. officinalis, S. elegans and T. zygis subsp. zygis as active ingredients for natural cosmetic formulations.