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- Evaluation of berberine nanoparticles as a strategy to modulate acetylcholinesterase activityPublication . Leimann, Fernanda Vitória; Souza, Luma Borges de; Oliveira, Byanca Pereira Moreira de; Rossi, Bruna Franzon; Silva, Patricia Sabino da; Shiraishi, Carlos Seiti Hurtado; Kaplum, Vanessa; Abreu, Rui M.V.; Pereira, Carla; Barros, Lillian; Peron, Ana Paula; Ineu, Rafael Porto; Oechsler, Bruno Francisco; Sayer, Claudia; Araujo, Pedro Henrique Hermes de; Gonçalves, Odinei Hess; Shiraishi, Carlos S.H.Researchers have concentrated efforts in the search for natural-based reversible inhibitors for cholinesterase enzymes as they may play a key role in the treatment of degenerative diseases. Diverse plant alkaloids can inhibit the action of acetylcholinesterase and, among them, berberine is a promising bioactive. However, berberine has poor water solubility and low bioavailability, which makes it difficult to use in treatment. The solid dispersion technique can improve the water affinity of hydrophobic substances, but berberine solid dispersions have not been extensively studied. Safety testing is also essential to ensure that the berberine-loaded solid dispersions are safe for use. This study investigated the effectiveness of berberine-loaded solid dispersions (SD) as inhibitors of acetylcholinesterase enzyme (AChE). Docking simulation was used to investigate the influence of berberine on AChE, and in vitro assays were conducted to confirm the enzymatic kinetics of AChE in the presence of berberine. Berberine SD also showed improved cytotoxic effects on tumoral cells when dispersed in aqueous media. In vivo assays using Allium cepa were implemented, and no cytotoxicity/genotoxicity was found for the berberine solid dispersion. These results suggest that berberine SD could be a significant step towards safe nanostructures for use in the treatment of neurodegenerative diseases.
- Mycorrhization and micropropation of chestnut (Castanea sativa Mill.) seedlings as tools to obtain high added-value phenolic compoundsPublication . Dias, Maria Inês; Pinela, José; Pereira, Carla; Ferreira, Patrícia; Oliveira, Maria de Fátima; Martins, Anabela; Afonso, Andreia; Barros, LillianMiChestnut3 is a project of the company DEIFIL whose main objective is to produce more resistant and productive hybrid chestnut (Castanea sativa Mill.) seedlings through micropropagation and mycorrhization techniques. In this work, in addition to the agronomic traits of the micropropagated mycorrhizal chestnut seedlings, it was also important to evaluate the changes induced by mycorrhization in the phenolic profile of these plants. Phenolic compounds are plant secondary metabolites involved in plant-microbe interactions/symbiosis and act as signaling molecules in the establishment of arbuscular mycorrhizal symbioses, as well as in plant defense mechanisms [1]. According to the literature, considerable increases in phenolic compounds in host plants as a result of arbuscular mycorrhizal fungus inoculation have been reported during the progression of the infection [1]. Therefore, this work was carried out to study the impact of the type of fungal inoculum and the period of mycorrhization (before or after potting) on the qualitative and quantitative profile of phenolic compounds of the roots and leaves of the chestnut seedlings produced by DEIFIL. After collection and lyophilization of the plant material, hydroethanolic extracts were prepared and the phenolic compounds were characterized by HPLC-DAD-ESI/MS [2]. Ellagic acid derivatives and Oglycosylated flavonoids were the major phenolic compounds in both plant roots and leaves, which agreed with previous reports [2,3]. A statistical analysis showed that the type of inoculum and period of mycorrhization significantly (p<0.05) affected the phenolic profile of the chestnut hybrids. In general, the mycorrhizal seedlings with the fungi Amanita caesarea and Boletus edulis were those that presented the highest levels of phenolic compounds. Relationships between the levels of these signaling compounds and the agronomic performance of chestnut seedlings were also found. The results bring new perspectives into the future production of a hybrid chestnut tree resistant to ink disease in the main traditional Portuguese varieties
- Red seaweeds as a source of nutrients and bioactive compounds: Optimization of the extractionPublication . Carpena Rodríguez, María; Caleja, Cristina; Pereira, Eliana; Pereira, Carla; Ćirić, Ana; Soković, Marina; Soria-Lopez, Anton; Fraga-Corral, Maria; Simal-Gandara, Jesus; Ferreira, Isabel C.F.R.; Barros, Lillian; Prieto Lage, Miguel A.The present work aimed to determine the nutritional composition (ash, protein, fat, carbohydrate content and energy value), phenolic compounds, pigments and organic acids content of three typical red algae from the Northwest of Spain: Chondrus crispus, Mastocarpus stellatus, and Gigartina pistillata; as well as their antioxidant and antimicrobial activities. Furthermore, the present work compared two extraction techniques: conventional heat assisted extraction (HAE) and high pressure assisted extraction (HPAE) to maximize the yield and the concentration of target compounds. Different independent variables were considered for the response study. Time (t) and percentage of ethanol of the solvent (S) were chosen for both techniques and temperature (T) and pressure (P) were used for HAE and HPAE, respectively. The experiments were designed following a response surface methodology (RSM) approach. The obtained results showed a similar nutritional composition between algae samples: low-fat content and high content of proteins, carbohydrates and energy. All tested algae showed good antioxidant and antimicrobial properties. Finally, HEA demonstrated to be the most efficient extraction technique. This study confirms the potential of red algae to be part of the human diet as a source of non-animal protein, due to its nutritional content, phenolic profile, pigments concentration and bioactive properties, which proves that HAE is the optimum technique for the extraction maximization.
- Phenolic profile and antimicrobial activity of different dietary supplements based on Cochlospermum angolensis WelwPublication . Pereira, Carla; Barros, Lillian; Alves, Maria José; Pereira, Liliana; Santos-Buelga, Celestino; Ferreira, Isabel C.F.R.Three different formulations (infusion, pills and syrup) of Cochlospermum angolensis were characterized by HPLC-DAD-ESI/MS regarding phenolic composition, and evaluated by their in vitro antimicrobial activity against clinical isolates of multiresistant bacteria. Infusion and pills showed the highest variety of phenolic compounds, with eleven molecules identified. Protocatechuic acid was only present in infusions, being the most abundant compound, while (epi)gallocatechin-O-gallate was the main molecule identified in pills and eucaglobulin/globulusin in syrup. Infusion revealed antimicrobial activity against all the studied bacteria with the exception of Proteus mirabilis whereas the pills revealed activity in Escherichia coli spectrum extended producer of β-lactamases and methicillin-resistant Staphylococcus aureus. In the syrup there was no antimicrobial activity detected, which is in agreement with its low concentrations of phenolic compounds. None of the formulations inhibited P. mirabilis. Considering the obtained results, C. angolensis infusion can be considered a good source of phenolic compounds as well as a good antimicrobial agent.
- Blueberry juice as a nutritious and bioactive beverage to be included in novel food productsPublication . Backes, Emanueli; Saldanha, Ana Luísa; Molina, Adriana K.; Pereira, Carla; Dias, Maria Inês; Ferreira, Isabel C.F.R.; Barros, LillianBlueberry ( Vaccinium myrtillus L.) is a very popular fruit, native from the northern hemisphere and consumed worldwide. It has been widely studied for being a rich source of bioactive compounds with recognized beneficial properties for Human health [1]. Therefore, several industrialized products, such as juices and derivatives, have been developed from blueberry fruit, aiming at most practical forms of consumption. In this sense, the present work aimed to analyse the blueberry juice in terms of nutritional value, following AOAC procedures, and chemical compositions, namely in free sugars, by HPLC-RI, organic acids, by UFLC-PDA, and phenolic compounds, by HPLC-DAD/ESI-MS. Moreover, the antioxidant capacity, by TBARS and OxHLIA assays, was also assessed to validate its bioactive properties. Regarding the nutritional value, carbohydrates were the major macronutrients found in blueberry juice, followed by ash and protein. In terms of free sugars, fructose and glucose were detected, with a higher concentration of fructose. Four organic acids were also identified in the juice, namely oxalic, quinic, malic, and shikimic acids, being quinic acid the most abundant one. In what concerns the phenolic composition, four phenolic acids (quinic acid, caffeic acid hexoside, cis 5- O- caffeoylquinic acid, and trans 5- O -caffeoylquinic acid) and six anthocyanins (cyanidin-3- O -glucoside, cyanidin-3- O -pentoside, peonidin-3- O glucoside, peonidin-3- O -pentoside, malvidin-3- O -glucoside, and malvidin-3- O -pentoside) were detected. As expected, considering its chemical composition, the juice also presented a strong antioxidant capacity, being able of inhibiting the lipid peroxidation and the oxidative hemolysis. The results obtained in the present study validate the nutritional and bioactive quality of the juice obtained from Vaccinium myrtillus L., justifying its application in the development of novel foodstuff.
- Gastrointestinal digestion of yerba mate, rosemary and green tea extracts and their subsequent colonic fermentation by human, pig or rat inoculaPublication . Correa, Vanesa G.; Garcia-Manieri, Jessica Amanda Andrade; Dias, Maria Inês; Pereira, Carla; Mandim, Filipa; Barros, Lillian; Ferreira, Isabel C.F.R.; Peralta, Rosane M.; Bracht, AdelarPolyphenolic compounds are common constituents of human and animal diets and undergo extensive metabolism by the gut microbiota before entering circulation. In order to compare the transformations of polyphenols from yerba mate, rosemary, and green tea extracts in the gastrointestinal tract, simulated gastrointestinal digestion coupled with colonic fermentation were used. For enhancing the comparative character of the investigation, colonic fermentation was performed with human, pig and rat intestinal microbiota. Chemical analysis was performed using a HPLC system coupled to a diode-array detector and mass spectrometer. Gastrointestinal digestion diminished the total amount of phenolics in the rosemary and green tea extracts by 27.5 and 59.2 %, respectively. These reductions occurred mainly at the expense of the major constituents of these extracts, namely rosmarinic acid (-45.7 %) and epigalocatechin gallate (-60.6 %). The yerba mate extract was practically not affected in terms of total phenolics, but several conversions and isomerizations occurred (e.g., 30 % of trans-3-Ocaffeoylquinic acid was converted into the cis form). The polyphenolics of the yerba mate extract were also the least decomposed by the microbiota of all three species, especially in the case of the human one (-10.8 %). In contrast, the human microbiota transformed the polyphenolics of the rosemary and green extracts by 95.9 and 88.2 %, respectively. The yerba mate-extract had its contents in cis 3-O-caffeoylquinic acid diminished by 78 % by the human microbiota relative to the gastrointestinal digestion, but the content of 5-O-caffeoylquinic acid (also a chlorogenic acid), was increased by 22.2 %. The latter phenomenon did not occur with the rat and pig microbiota. The pronounced interspecies differences indicate the need for considerable caution when translating the results of experiments on the effects of polyphenolics performed in rats, or even pigs, to humans.
- HPLC-DAD-ESI/MS profiling of phytochemicals in Aesculus hippocastanum fruitPublication . Dias, Maria Inês; Pereira, Carla; Albiston, Carly; Pinela, José; Barros, LillianAesculus hippocastanum L. (Sapindaceae) is a large, broad-crowned deciduous tree cultivated as an ornamental in urban areas in the Northern hemisphere. Among the scientific community, it is known mainly for steroidal glycosides, among which aescin is the main active constituent and responsible for most of its medicinal properties [1,2]; but other bioactive compounds such as flavonol glycosides have also been described in this plant [3]. In folk medicine, while the bark has been used to treat dermatitis, the leaves and seeds are used for their antiinflammatory effect [2]. In Europe, seed extracts and supplements have been used to treat varicose veins among other venous disorders [4]. Therefore, this study aimed to characterize the phenolic and saponin profiles of the kernel, shell, and husk of the horse chestnut fruit. After separating, lyophilizing, and grinding the three fruit parts, hydroethanolic extracts were prepared by sonoextraction at 400 W (20 kHz) for 40 min. The chromatographic separation and identification of phenolic compounds and saponins were achieved by high-performance liquid chromatography coupled with photodiode array detection and electrospray ionization tandem mass spectrometry (HPLC-DAD-ESI/MS), using different elution gradients [5]. It was possible to identify 31 phenolic compounds in the hydroethanolic extracts, including phenolic acids (caffeic acid and p-coumaroyl derivatives), flavan-3-ols ((+)-catechin and (-)- epicatechin derivatives), and flavonols (O-glycosylated quercetin, isorhamnetin derivatives, and kaempferol). While flavonols and flavan-3-ols predominated in the seed kernel and shell, respectively, the husk had comparable amounts of both phenolic constituents. The four main aescin saponins were consistently detected in the seed kernel extracts, namely aescin Ia and Ib (β-aescin) and isoaescin Ia and Ib (α-aescin). Overall, the different parts of the inedible horse chestnut fruit have a different phytochemical profile in qualitative and quantitative terms. Further studies will be important to evaluate biological activities of the different seed extracts
- Phytochemical profile and biological activities of 'Ora-pro-nobis' leaves (Pereskia aculeata Miller), an underexploited superfood from the Brazilian Atlantic ForestPublication . Garcia, Jéssica A.A.; Corrêa, Rúbia C.G.; Barros, Lillian; Pereira, Carla; Abreu, Rui M.V.; Alves, Maria José; Calhelha, Ricardo C.; Bracht, Adelar; Peralta, Rosane M.; Ferreira, Isabel C.F.R.South to Northeast of Brazil, ora-pro-nobis leaves are used in traditional cuisine, featuring as an ingredient of various sweet and savoury dishes. In some low-income communities, it is known as the ‘meat of the poor’, being the main protein source available.1 The aim of the present work was to perform an inedited study on the phytochemical profile and some biological activities of P. aculeate leaves, with the view of expanding the current knowledge on the potentialities of this superfood. For this purpose, its hydroethanolic extract was characterized in terms of phenolic composition, antioxidant, and antibacterial capabilities and finally the hepatotoxicity of the extract was evaluated. A total of ten phenolic compounds were identified via high-performance liquid chromatography coupled to diode array detector and mass spectrometer (HPLC–DAD–ESI/MSn): two phenolic acids (caffeic acid derivatives) and eight flavonoids (quercetin, kaempferol and isorhamnetin glycoside derivatives). Caftaric acid was the extract’s major phenolic constituent, accounting for more than 49% of the phenolic content, followed by quercetin-3-O-rutinoside (14.99%) and isorhamnetin-O-pentoside-O-rutinoside (9.56%). The total phenolic content found in the hydromethanolic extract was relevant (23.75 mg/g). A broad study of the extracts’ antioxidant activity was carried out, using a set of five distinct methods: two cell-based methods (1) oxidative haemolysis inhibition assay (OxHLIA); (2) the inhibition of the production of thiobarbituric acid reactive substances (TBARS); besides three chemical in vitro assays (3) reduction of the 2,2-diphenyl-1-picrylhydrazyl radical (DPPH); (4) reduction of the 2,2-azino-bis (3-ethylbenzothiazoline-6-sulphonate) cation (ABTS) and (5) hydroxyl radical scavenging assay.2 Overall, the ora-pro-nobis leaf extract showed relevant values of antioxidant activity, even higher than Trolox in the DPPH and ABTS trials. The antioxidant activity verified for the hydroethanolic leaf extract of P. aculeata is possibly related to its phenolic composition; the predominant constituents of the extract, i.e. caftaric acid and rutin, have widely proven antioxidant activities.1 Furthermore, the evaluated extract showed no toxicity against a non-tumour liver primary culture PLP2, at the highest tested concentration (400 μg/mL). The antimicrobial activity exhibited by the extract against both Gram-positive (Enterococcus faecalis, Listeria monocytogenes, MRSA – Methicillin-resistant Staphylococcus aureus) and Gram-negative (Escherichia coli, Klebsiella pneumoniae, Morganella morganii, Proteus mirabilis, and Pseudomonas aeruginosa) bacteria (MIC values between 5 to 20 mg/mL) suggests the presence of a broad spectrum of phytochemicals with antimicrobial activity. The extract was more active against K. pneumonia than the antibiotic ampicillin, whereas against M. morganii it presented equivalent inhibitory effect. Therefore, the information reported here not only corroborates the importance of the production and consumption of P. aculeata leaves by the low income population to improve nutrition, but also reinforces their potential as a sustainable source of promising food ingredients to be used both for food enrichment and preservation.
- Recovery of anthocyanins from sweet cherry wastes: process modeling and optimization using response surface methodologyPublication . Pereira, Carla; Barros, Lillian; Prieto Lage, Miguel A.; Ferreira, Isabel C.F.R.Sweet cherries (P. avium L.) are widely consumed fruits appreciated for their sweet taste and appealing appearance. Their colour vary with the maturation stage, being an excellent indicator of the optimal harvest time. When ripen, these fruits acquire a dark red coloration that is mainly influenced by the anthocyanin concentration in the fruit peel and pulp [1]. These compounds are present in several natural matrices and their colour can vary from blue to violet and red depending on the surrounding medium conditions (pH, temperature, humidity, salinity, stress and storage conditions, etc.) [2]. Beyond bioactive properties, these compounds also possess a great coloring capacity, which justify their increasing exploitation for food industry application, especially for cherry wastes recovery, given the fact that bird bitten and fallen fruits are not suitable for sale nor consumption and represent a significant part of the production. Thus, the aim of the present work was to optimize the extraction of these compounds from sweet cherry wastes, by studying the conditions that maximize the maceration extraction yield. For that purpose, a response surface methodology was applied using five levels for each of the independent variables (time, temperature, and solvent concentration). The quantification of anthocyanins present in the extracts was performed by high performance liquid chromatography coupled to a diode array detector (HPLC-DAD). For the model application, the anthocyanin concentration and the extraction yield were used as responses. Through this extraction method, it was possible to obtain a yield of 1.86±0.41 mg/g of cherry dry weight, in the optimal conditions of: 63.0±3.2 min; 61.7±1.3ºC and 53.1±1.4% of ethanol. The obtained residue represented 87% of the total cherry dry weight and the anthocyanin content was of 3.05±0.41 mg/g of dry residue. The results obtained in this study demonstrate the potential application of sweet cherries as sources of anthocyanins.
- Exploring the impacts of sorghum (Sorghum bicolor L. Moench) germination on the flour’s nutritional, chemical, bioactive, and technological propertiesPublication . Salvati, Diogo; Paschoalinotto, B. H.; Mandim, Filipa; Ferreira, Isabel C.F.R.; Steinmacher, Nádia Cristiane; Pereira, Carla; Dias, Maria InêsGermination is a natural, simple, and economical process used to improve the quality of nutritional and technological grains. In this study, native and sprouted sorghum flours were characterized regarding their technological properties (particle size distribution, water, and oil absorption capacity, swelling power and solubility, microscopy of starch granules, and pasting and thermal properties). Nutritional and phytochemical characterization profiles, including free sugars, fatty acids, organic acids, tocopherols, and phenolic compounds, were explored through chromatographic methods. The antioxidant, anti-inflammatory, and cytotoxic activities of the respective hydroethanolic extracts were also evaluated. The results showed that the germination process caused significant changes in the flour composition and properties, causing reduced gelatinization temperature and retarded starch retrogradation; an increased content of free sugars and total organic acids; and a decreased content of tocopherols and phenolic compounds. In terms of bioactivity, the sprouted sorghum flour extract showed better lipid-peroxidation-inhibition capacity and none of the extracts revealed hepatotoxicity or nephrotoxicity, which are important results for the validation of the use of the flours for food purposes. Germination is an efficient and alternative method for grain modification that gives improved technological properties without chemical modification or genetic engineering.