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- Inhibitory Effects of Aqueous and Hydroalcoholic Extracts from Jatobá Coat (Hymenaea courbaril L.) on Pancreatic Amylase and Starch AbsorptionPublication . Polo, Ana Caroline; Uber, Thaís Marques; Souza, Gustavo Henrique; Corrêa, Rúbia C.G.; Santos Filho, José Rivaldo dos; Sá-Nakanishi, Anacharis Babeto de; Seixas, Flávio Augusto Vicente; Bracht, Adelar; Peralta, Rosane MarinaJatobá (Hymenaea courbaril) is a native tree abundant in Brazil. The fruit coat is an industrial by-product of jatobá flour processing, typically discarded. Presently, within the circular bioeconomy concept, there are efforts underway that aim at finding economically viable applications for the bio-residues of jatobá. Within this context, the present work attempts to find possible applications for the jatobá coat in glycemic control through inhibition of α-amylase activity. Aqueous and hydroethanolic extracts were used. In vitro experiments included detailed kinetic studies with an α-amylase catalyzed reaction. Starch absorption in vivo was assessed by means of a starch tolerance test in mice. Both extracts inhibited α-amylase. The IC50 values for the aqueous and hydroalcoholic extracts were 81.98 ± 3.53 µg/mL and 51.06 ± 0.42 µg/mL, respectively. The inhibition was of the non-competitive type. Both extracts reduced hyperglycemia caused by starch administration in mice, the aqueous extract being effective over a larger dose range. This action can be attributed to the α-amylase inhibition. In silico studies suggested that procyanidin dimers, taxifolin 7-O-rhamnoside, and quercetin 7-rhamnoside contribute, but several other not-yet-identified substances may be involved. The findings suggest that aqueous and hydroalcoholic extracts from jatobá coat warrant further investigations as potential modulators of glycemia following starch ingestion.
- Effects of in vitro gastrointestinal digestion and colonic fermentation on a rosemary (Rosmarinus officinalis L) extract rich in rosmarinic acidPublication . Gonçalves, Geferson A.; Corrêa, Rúbia C.G.; Barros, Lillian; Dias, Maria Inês; Calhelha, Ricardo C.; Corrêa, Vanesa G.; Bracht, Adelar; Peralta, Rosane M.; Ferreira, Isabel C.F.R.The potential phytochemical losses occurring throughout the sequential steps of in-vitro gastrointestinal digestion and colonic fermentation of a rosemary aqueous extract were investigated. Crude (CE), digested (DE) and fermented (FE) extracts were characterized in terms of their phenolic profile and biological activities. Rosmarinic acid was the phytochemical that underwent the most significate transformation during digestion and fermentation, which amounted to 60% compared to the 26% degradation of the total phenolics. Overall, the simulated digestion step decreased the antioxidant activity estimated by DPPH, ABTS, FRAP, ORAC and TBARS assays. Both CE and DE did not present antiproliferative potential, however, FE exhibited a pronounced cytotoxic activity (GI50 = 116 µg/mL) against HeLa cells. CE and DE showed to be moderate inhibitors of methicillin-resistant Staphylococcus aureus (MRSA), methicillin-susceptible S. aureus (MSSA), S. aureus, Listeria monocytogenes, whilst the FE acted as a moderate inhibitor of MRSA and MSSA.
- MycosterolsPublication . Uber, Thaís Marques; Backes, Emanueli; Corrêa, Rúbia C.G.; Corrêa, Vanesa G.; Bracht, Adelar; Peralta, Rosane M.Sterols are amphipathic lipids that play essential roles in the physiology of eukaryotic organisms in general. The fungal sterols are collectively known as mycosterols and they exert numerous physiological functions. For humans, the interest on this class of compounds relies heavily on the fact that they can promote health benefits. For this reason, fungal extracts rich in sterols of various forms are valuable and promising ingredients. One of the best-known benefits of mycosterols is their inhibitory actions on cholesterol absorption and biosynthesis, but there are several interesting regulatory and modulatory phenomena that mycosterols can affect and that might eventually be of therapeutic interest. Within this domain, the practical application of mycosterols or mycosterol-enriched fungal extracts presents several challenges. The latter include isolation of novel bioactive mycosterols from still underexploited fungi species, the optimization of existing methodologies for production and recovery, extensive study of their applications and, finally, substantial clinical trials for attesting their health benefits and safety.
- Impact of in vitro gastrointestinal digestion and colonic fermentation on the phenolic composition and bioactivities of Rosmarinus officinalis L.Publication . Dias, Maria Inês; Corrêa, Rúbia C.G.; Gonçalves, Geferson A.; Barros, Lillian; Calhelha, Ricardo C.; Correa, Vanesa G.; Bracht, Adelar; Peralta, Rosane M.; Ferreira, Isabel C.F.R.Rosmarinus officinalis L. (Lamiaceae) is a plant native to the Mediterranean, popularly known as rosemary. In addition to its culinary use, it has also been used for therapeutic purposes since antiquity [1]. The European Union has considered rosemary extract as a safe and efficient food preservative, being rosmarinic acid (RA) its main constituent [2]. Extracts rich in RA not only have anti-inflammatory, antioxidant and hepatoprotective effects [1], but also prevent oxidation in foods without compromising their sensory acceptance. However, information on the stability of bioactive compounds in rosemary extract is scarce. The aim of this work was to investigate the potential phytochemical losses occurring throughout the sequential steps of in vitro gastrointestinal digestion and colonic fermentation of a rosemary aqueous extract. For this purpose, the crude (CE), digested (DE) and fermented (FE) extracts were characterized in terms of their phenolic profile and biological activities. Rosmarinic acid was the phytochemical that underwent the most significate transformation during digestion and fermentation, which amounted to 60% compared to the 26% degradation of the total phenolic compounds. Overall, the simulated digestion step decreased the antioxidant activity estimated by DPPH, ABTS, FRAP, ORAC and TBARS assays. Both CE and DE did not present anti-proliferative potential, however, FE exhibited a pronounced cytotoxic activity (GI50 = 116 μg/mL) against HeLa cervical carcinoma cell line. CE and DE showed to be moderate inhibitors of methicillin resistant Staphylococcus aureus (MRSA), methicillin-susceptible S. aureus (MSSA), and Listeria monocytogenes, whilst the FE acted as a moderate inhibitor of MRSA and MSSA. In view of the relevant biological activities confirmed in this study, it is possible to suggest the application of the rosemary aqueous extract as a food additive, either as a preservative and/or as a functional ingredient. However, the use of RA-rich formulations in food industry should consider the stability and bioavailability of this bioactive compound.
- 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.
- Polyphenolic profile and pharmacological activities of whips horse (Luehea divaricata) bark extracts studied using in vitro and in vivo systemsPublication . Garcia-Manieria, Jéssica A.A.; Correa, Vanesa G.; Corrêa, Rúbia C.G.; Dias, Maria Inês; Calhelha, Ricardo C.; Ivanov, Marija; Soković, Marina; Barros, Lillian; Ferreira, Isabel C.F.R.; Bracht, Adelar; Peralta, Rosane M.Leaves and barks of Luehea divaricata (Malvaceae) are used in folk medicine for the treatment of infectious diseases, tumors, rheumatism and diabetes. This work presents in vivo experiments (rats and mice) supported by in vitro and chemical analyses in order to address the above mentioned folk medicinal uses. The phenolic constituents of both aqueous and hydroalcoholic extracts are mainly catechin derivatives (135.4 and 215.9 mg/g, respectively). Both extracts displayed strong antioxidant activity. They also showed antiproliferative activities against tumor cells, nitric oxide synthesis inhibition (indicative of anti-inflammatory activity) and antimicrobial activity against a variety of infectious agents. Paracetamol-induced liver injury in rats, which has a high inflammatory component, was substantially attenuated in animals treated with the hydro- alcoholic extract (200 mg kg−1 day−1). This was deduced from aspartate aminotransferase and alanine aminotransferase measurements in plasma as well as from the hepatic activities of catalase and superoxide dismutase. Both extracts inhibited the pancreatic α-amylase with IC50 values of 11.50±0.05 and 18.70±3.87 μg/mL for the hydro-alcoholic and aqueous extract, respectively. Both extracts inhibited starch digestion in mice at the doses of 200 and 400 mg/kg. In general terms the results confirm several of the vox populi notions about the therapeutic potential of L. divaricata, the antidiabetic action, combined with the hepatoprotective effect, being the most relevant observations. Not less important is the economical perspective for the rural producers which may eventually increase their revenue by selling increasingly valued raw materials derived from L. divaricata based on its therapeutic properties.
- Optimization of ergosterol extraction from Agaricus blazei Murrill using response surface methodology (RSM)Publication . Taofiq, Oludemi; Corrêa, Rúbia C.G.; Barros, Lillian; Prieto Lage, Miguel A.; Bracht, Adelar; Peralta, Rosane M.; González-Paramás, Ana María; Barreiro, M.F.; Ferreira, Isabel C.F.R.Different approaches have been utilized to lower environmental impacts of by-products from industrial processes and this involves conversion of biological wastes, agricultural residues and waste streams into high value-added products, thereby delivering positive economic, environmental and scientific impact [1]. Mushroom production has increased recently due to their use as ingredients in preparation of nutraceutical, pharmaceutical and cosmeceutical formulations. During mushrooms sorting, an expressive volume is discarded because they do not fit into commercial standard even though their content in biomolecules is not compromised. RSM was applied to optimize the recovery of ergosterol from the fruiting bodies of Agaricus blazei Murrill by comparing conventional (heat-assisted extraction, HAE) and non-conventional techniques (ultrasound and microwave-assisted extractions, UAE and MAE, respectively). The used response criteria were the quantification of ergosterol by HPLC-UV and the extraction yield (%). The optimum conditions were predicted as 150 min, 81.6 ºC for HAE, 30 min, 400W for UAE, and 25 min, 134.6 ºC, for the MAE system. Considering both responses, MAE (25.44 mg/100 g dw, 21 %); UAE (21.49 mg/100 g dw, 11.03 %) and HAE (18.84 mg/100 g dw, 17.05 %), the MAE system was identified as the best technique followed by UAE and HAE. The values predicted by the model are in close agreement with the experimental observations, proving the validity of the model and the usefulness of the predictions for future scale up. The obtained ergosterol-rich extracts can be applied as bioactive ingredients for pharmaceutical, cosmeceutical and nutraceutical purposes.
- Phytochemicals and bioactive properties of Ilex paraguariensis: an in-vitro comparative study between the whole plant, leaves and stemsPublication . Souza, Aloisio Henrique Pereira de; Corrêa, Rúbia C.G.; Barros, Lillian; Calhelha, Ricardo C.; Santos-Buelga, Celestino; Peralta, Rosane M.; Bracht, Adelar; Matsushita, Makoto; Ferreira, Isabel C.F.R.Leaves, stems and whole plant of Ilex paraguariensis (yerba mate) were characterized in terms of their chemical composition and biological activities in order to determine which part of the plant is more interesting to develop bioactive formulations. The yerba mate samples contain at least five free sugars, five organic acids, eighteen fatty acids, one tocopherol, nine hydroxycinnamoyl derivatives and two flavonols. The leaves extract revealed the highest antioxidant activity, correlating with its highest levels of phenolic compounds. By contrast, the stems extract showed the highest anti-inflammatory potential and was also the most potent against MCF-7 and HepG2 cell lines, probably due to the presence of other phytochemicals. The absence of hepatotoxicity of the extracts was confirmed in porcine liver primary cells. Although the yerba mate extracts have been widely studied, this report shows for the first time the distinct potentialities of each individual part of the plant.
- Chemical composition, nutritional value, and biological evaluation of tunisian okra pods (abelmoschus esculentus L. moench)Publication . Romdhane, Mariem Haj; Chahdoura, Hassiba; Barros, Lillian; Dias, Maria Inês; Corrêa, Rúbia C.G.; Morales, Patricia; Ciudad-Mulero, María; Flamini, Guido; Majdoub, Hatem; Ferreira, Isabel C.F.R.The aim of this work was to perform an unprecedented in-depth study on the bioactive phytochemicals of Abelmoschus esculentus L. Moench Tunisian landrace (Marsaouia). For this purpose, its nutritional, aroma volatile, and phenolic profiles were characterized, and sundry biological activities were assessed in vitro. The approximate composition revealed that total dietary fiber as the most abundant macronutrient, mainly insoluble dietary fiber, followed by total carbohydrates and proteins. In addition, okra pods were rich in K, Ca, Mg, organic acids, tocopherols, and chlorophylls. Gas Chromatography-Electron Impact Mass Spectrometry (GC-EIMS) analysis showed that oxygenated monoterpenes, sesquiterpene hydrocarbons, and phenylpropanoids were the predominant essential volatile components in A. esculentus pods. A total of eight flavonols were detected by High-Performance Liquid Chromatography coupled to a DAD detector and mass spectrometry by electrospray ionization (HPLC-DAD-MS/ESI); with quercetin-3-O-glucoside being the majority phenolic component, followed by quercetin-O-pentosyl-hexoside and quercetin-dihexoside. This pioneering study, evidences that Tunisian okra display promising antioxidant and cytotoxic actions, in addition to relevant inhibitory effects against α-amylase and α-glucosidase enzymes, and interesting analgesic activity.
- Insights into the chemical composition and in vitro bioactive properties of mangosteen (Garcinia mangostana L.) pericarpPublication . Albuquerque, Bianca R.; Dias, Maria Inês; Pinela, José; Calhelha, Ricardo C.; Pires, Tânia C.S.P.; Alves, Maria José; Corrêa, Rúbia C.G.; Ferreira, Isabel C.F.R.; Oliveira, Beatriz; Barros, LillianThe industrial processing of mangosteen (Garcinia mangostana L.) generates high amounts of waste, as similar to 60% of the fruit is formed by an inedible pericarp. However, its pericarp has been explored as a source of xanthones; nevertheless, studies addressing the recovery of other chemical compounds from such biomass are still scarce. Hence, this study intended to elucidate the chemical composition of the mangosteen pericarp, including fat-soluble (tocopherols and fatty acids) and water-soluble (organic acids and phenolic compound non-xanthones) compounds present in the following extracts: hydroethanolic (MT80), ethanolic (MTE), and aqueous (MTW). In addition, the antioxidant, anti-inflammatory, antiproliferative and antibacterial potentials of the extracts were assessed. The mangosteen pericarp showed a composition with seven organic acids, three tocopherol isomers, four fatty acids and fifteen phenolic compounds. Regarding the extraction of phenolics, the MT80 was the most efficient (54 mg/g extract), followed by MTE (19.79 mg/g extract) and MTW (4.011 mg/g extract). All extracts showed antioxidant and antibacterial activities; however, MT80 and MTE extracts were more efficient than MTW. Only MTW did not show anti-inflammatory properties, whereas MTE and MT80 showed inhibitory activities towards tumor cell lines. Notwithstanding, MTE showed cytotoxicity towards normal cells. Our findings support the idea that the ripe mangosteen pericarp is a source of bioactive compounds, although their recovery is dependent on the extraction solvent.