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- Antioxidant activity and in vitro inhibition of tumor cell growth by leaf extracts from the carob tree (Ceratonia siliqua)Publication . Custódio, Luísa; Fernandes, Eliana; Escapa, Ana Luísa; López-Avilés, Sandra; Fajardo, Alba; Aligué, Rosa; Alberício, Fernando; Romano, AnabelaThe methanol leaf extracts of female cultivars of the carob tree [Ceratonia siliqua L. (Fabaceae)] and of hermaphrodite and male trees were investigated for their contents of phenolic compounds, their in vitro antioxidant activity, measured by 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging and linoleic acid system assays, and their in vitro tumor growth inhibition on HeLa cells. The different cultivars and trees showed high levels of phenols, and considerable variations in the amount of these compounds. The extracts showed significant radical scavenging activity (RSA), which was not significantly affected by the gender of the tree. From the female cultivars tested, Galhosa exhibited the highest RSA. Gender significantly affected the antioxidant activity of the extracts measured by the linoleic acid system assay, and males and hermaphrodites showed the highest activities. The extracts displayed a remarkable ability to inhibit tumor cell proliferation, and their bioactivity varied with different cultivars or trees tested. Extracts from male and hermaphrodite trees exhibited higher capacity to inhibit the proliferation of HeLa cells than the female cultivars.
- Isolation of a euryhaline microalgal strain, Tetraselmis sp CTP4, as a robust feedstock for biodiesel productionPublication . Pereira, Hugo; Gangadhar, Katkam N.; Schulze, Peter S.C.; Santos, Tamara; de Sousa, Carolina Bruno; Schueler, Lisa; Custódio, Luísa; Malcata, F. Xavier; Gouveia, Luísa; Varela, J.; Barreira, LuísaBioprospecting for novel microalgal strains is key to improving the feasibility of microalgae-derived biodiesel production. Tetraselmis sp. CTP4 (Chlorophyta, Chlorodendrophyceae) was isolated using fluorescence activated cell sorting (FACS) in order to screen novel lipid-rich microalgae. CTP4 is a robust, euryhaline strain able to grow in seawater growth medium as well as in non-sterile urban wastewater. Because of its large cell size (9-22 mu m), CTP4 settles down after a six-hour sedimentation step. This leads to a medium removal efficiency of 80%, allowing a significant decrease of biomass dewatering costs. Using a two-stage system, a 3-fold increase in lipid content (up to 33% of DW) and a 2-fold enhancement in lipid productivity (up to 52.1 mg L-1 d(-1)) were observed upon exposure to nutrient depletion for 7 days. The biodiesel synthesized from the lipids of CTP4 contained high levels of oleic acid (25.67% of total fatty acids content) and minor amounts of polyunsaturated fatty acids with >= 4 double bonds (< 1%). As a result, this biofuel complies with most of the European (EN14214) and American (ASTM D6751) specifications, which commonly used microalgal feedstocks are usually unable to meet. In conclusion, Tetraselmis sp. CTP4 displays promising features as feedstock with lower downstream processing costs for biomass dewatering and biodiesel refining.
- Assessment and comparison of the properties of biodiesel synthesized from three different types of wet microalgal biomassPublication . Gangadhar, Katkam N.; Pereira, Hugo; Diogo, Herminio P.; Borges dos Santos, R. M.; Devi, B. L. A. Prabhavathi; Prasad, R. B. N.; Custódio, Luísa; Xavier Malcata, F.; Varela, João; Barreira, LuísaIn recent years, microalgae-based carbon-neutral biofuels (i.e., biodiesel) have gained considerable interest due to high growth rate and higher lipid productivity of microalgae during the whole year, delivering continuous biomass production as compared to vegetable-based feedstocks. Therefore, biodiesel was synthesized from three different microalgal species, namely Tetraselmis sp. (Chlorophyta) and Nannochloropsis oculata and Phaeodactylum tricornutum (Heterokontophyta), and the fuel properties of the biodiesel were analytically determined, unlike most studies which rely on estimates based on the lipid profile of the microalgae. These include density, kinematic viscosity, total and free glycerol, and high heating value (HHV), while cetane number (CN) and cold filter plugging point (CFPP) were estimated based on the fatty acid methyl ester profile of the biodiesel samples instead of the lipid profile of the microalgae. Most biodiesel properties abide by the ASTM D6751 and the EN 14214 specifications, although none of the biodiesel samples met the minimum CN or the maximum content of polyunsaturated fatty acids with a parts per thousand yen4 double bonds as required by the EN 14214 reference value. On the other hand, bomb calorimetric experiments revealed that the heat of combustion of all samples was on the upper limit expected for biodiesel fuels, actually being close to that of petrodiesel. Post-production processing may overcome the aforementioned limitations, enabling the production of biodiesel with high HHV obtained from lipids present in these microalgae.
- Euphorbia-derived natural products with potential for use in health maintenancePublication . Salehi, B.; Iriti, M.; Vitalini, S.; Antolak, H.; Pawlikowska, E.; Kręgiel, D.; Sharifi-Rad, J.; Oyeleye, S.; Ademiluyi, A.; Czopek, K.; Staniak, M.; Custódio, Luísa; Coy-Barrera, E.; Segura-Carretero, A.; Cádiz-Gurrea, M.; Capasso, R.; Cho, W.; Seca, A.Euphorbia genus (Euphorbiaceae family), which is the third largest genus of angiosperm plants comprising ca. 2000 recognized species, is used all over the world in traditional medicine, especially in the traditional Chinese medicine. Members of this taxa are promptly recognizable by their specialized inflorescences and latex. In this review, an overview of Euphorbia-derived natural products such as essential oils, extracts, and pure compounds, active in a broad range of biological activities, and with potential usages in health maintenance, is described. The chemical composition of essential oils from Euphorbia species revealed the presence of more than 80 phytochemicals, mainly oxygenated sesquiterpenes and sesquiterpenes hydrocarbons, while Euphorbia extracts contain secondary metabolites such as sesquiterpenes, diterpenes, sterols, flavonoids, and other polyphenols. The extracts and secondary metabolites from Euphorbia plants may act as active principles of medicines for the treatment of many human ailments, mainly inflammation, cancer, and microbial infections. Besides, Euphorbia-derived products have great potential as a source of bioactive extracts and pure compounds, which can be used to promote longevity with more health.
- A comparative study of the in vitro enzyme inhibitory and antioxidant activities of Butea monosperma (Lam.) Taub. and Sesbania grandiflora (L.) Poiret from Pakistan: New sources of natural products for public health problemsPublication . Baessa, M.; Rodrigues, Maria João; Pereira, Catarina; Santos, T.; Neng, N. da Rosa; Nogueira, J. M. F.; Barreira, Luísa; Varela, J.; Ahmed, H.; Asif, S.; Boukhari, S. A.; Kayani, W. K.; Ahmad, Khawaja Shafique; Zengin, G.; Mollica, A.; Custódio, LuísaInfusions, decoctions and tinctures were prepared from flowers of Butea monosperma (Lam.) Taub. and Sesbania grandiflora (L.) Poiret and evaluated for in vitro inhibition of enzymes implicated on the onset of neurological diseases (acetylcholinesterase: AChE and butyrylcholinesterase: BuChE), diabetes (alpha-glucosidase and alpha-amylase), obesity (lipase) and skin hyperpigmentation (tyrosinase). Extracts were also appraised for radical scavenging activity (RSA) on 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radicals, and for metal chelating activity on copper and iron ions. Samples were evaluated for their total contents in different phenolics groups by spectrophotometric methods, for phenolic profile by high performance liquid chromatography e diode array detection (HPLC-DAD) and for mineral contents by microwave plasma-atomic emission spectrometry (MP-AE). Regarding B. monosperma, the tincture allowed for a moderate inhibition of AChE, the decoction was able to inhibit alpha-glucosidase and no activity was observed towards BuChE, alpha-amylase or lipase. All extracts had a low or moderate inhibition towards tyrosinase, and significant RSA and metal chelating potential. As for S. grandiflora, only the decoction inhibited AChE, none of the extracts was able to inhibit BuChE, all samples inhibited alpha-glucosidase and infusions and decoctions had similar inhibitory properties towards alpha-amylase. None of the extracts was active against lipase, but all were able to inhibit tyrosinase. Extracts had also significant RSA, moderate copper chelation and decoctions had the capacity to chelate iron. The most abundant macroelements in both species were potassium and calcium, while iron was the prevalent microelement, especially in B. monosperma. Both species had significant levels of phenolic compounds, and the main components in decoctions and infusions of B. monosperma were syringic and salicylic acids, while the major compound identified in tinctures was the flavonoid luteolin-7-O-glucoside. In S. grandiflora the most abundant were chlorogenic and neochlorogenic acids and catechin hydrate. Molecular docking studies on the most abundant molecules in S. grandiflora, (+)-catechin, chlorogenic acid and neochlorogenic acid, indicate that these compounds are able to dock to alpha-glucosidase in a similar manner than acarbose. Our results suggest that flowers of both species are a promising source of high value-added compounds with enzyme inhibitory and antioxidant properties. (c) 2018 SAAB. Published by Elsevier B.V. All rights reserved.
- In vitro enzyme inhibitory and anti-oxidant properties, cytotoxicity and chemical composition of the halophyte Malcolmia littorea (L.) R.Br. (Brassicaceae)Publication . Castañeda-Loaiza, Viana; Placines, Chloé; Rodrigues, Maria Joao; Pereira, Catarina; Zengin, Gokhan; Neng, Nuno R.; Nogueira, José M. F.; Custódio, LuísaThis work reports for the first time the in vitro anti-oxidant (towards DPPH, ABTS, copper and iron), enzymatic inhibitory (on AChE, BuChE, α-glucosidase, α-amylase and tyrosinase), cytotoxicity (towards HepG2 and HEK 293 cells), and metabolomics (by HPLC-MS) of extracts from organs of Malcolmia littorea (L.) R.Br. Extracts were constituted mainly by phenolic acids and flavonoids, and main compounds were salicylic acid and luteolin-7-O-glucoside. Samples showed reduced radical scavenging and metal chelating capacity, and only the methanol extracts reduced iron. The root's ethanol and methanol extracts, and the aerial organ's ethanol extract exhibited the highest AChE inhibition. The root's ethanol extract displayed dual anti-cholinesterase activity. Samples showed a low capacity to inhibit α-amylase, but a high α-glucosidase inhibition was obtained with the root's and flower's ethanol extracts, and flower's methanol extract. Overall, samples displayed a high inhibition against tyrosinase, reduced HepG2 cellular viability and were less toxic towards HEK 293 cells.
- Combination of hyaluronic acid and PLGA particles as hybrid systems for viscosupplementation in osteoarthritisPublication . Mota, Ana Henriques; Direito, Rosa; Carrasco, Marta P.; Rijo, Patricia; Ascensao, Lia; Viana, Ana Silveira; Rocha, Joao; Eduardo-Figueira, Maria; Rodrigues, Maria Joao; Custódio, Luísa; Kuplennik, Nataliya; Sosnik, Alejandro; Almeida, Antonio Jose; Gaspar, Maria Manuela; Reis, Catarina PintoHyaluronic acid (HA) is commonly used through intra-articular administration for viscosupplementation in osteoarthritis and other disorders. HA is generally supplied as an injection commonly reported as painful, with strong limitations after treatment. In this study, an alternative delivery system was constructed based on HA hydrogel and poly(lactic-co-glycolic acid) (PLGA) particles with oleic acid. Development studies included the determination of particle toxicity, hemolytic activity, in vitro and in vivo anti-inflammatory activity using macrophages and a murine model, respectively. This study showed that empty PLGA particles presented a mean size of 373 nm, while particles containing HA and oleic acid showed a marked particle size increase. The HA association efficiency was of 73.6% and 86.2% for PLGA particles without and with oleic acid, respectively. The in vitro HA release from PLGA particles revealed a sustained profile. Particles showed a good in vitro cell compatibility and the risk of hemolysis was less < 1%, ensuring their safety. The in vivo anti-inflammatory study showed a higher inhibition for HA-loaded PLGA particles when compared to HA solution (78% versus 60%) and they were not different from the positive control, clearly suggesting that this formulation may be a promising alternative to the current HA commercial dosage form.
- Phytochemical characterization and bioactivities of five Apiaceae species: Natural sources for novel ingredientsPublication . Zengin, Gokhan; Mahomoodally, Mohamad Fawzi; Paksoy, Mehmet Yavuz; Picot-Allain, Carene; Glamocilja, Jasmina; Sokovic, Marina; Diuzheva, Alina; Jeko, Jozsef; Cziaky, Zoltan; Rodrigues, Maria Joao; Sinan, Kouadio Ibrahime; Custódio, LuísaSeveral species of the Apiaceae family have been employed in traditional cultures for their curative virtues. The present study focused on five Apiaceae species, (Falcaria vulgaris (FV), Smyrniopsis aucher( (SA), Smyrniopsis mtutzurdagensis (SM), Smyrnium cordifolium (SC), and Actinolema macrolema (AM)). The antioxidant, enzyme inhibitory (alpha-amylase, alpha-glucosidase, acetyl- and butyrylcholinesterase, lipase, and tyrosinase), antimicrobial, phytochemical, and cytotoxicity profiles of the methanol extracts of the selected Apiaceae species were determined. SC extract (35.68 mg gallic acid equivalent/g extract) possessed the highest phenolic content while the AM extract (56.79 mg rutin equivalent/g extract) had the highest flavonoid content. HPLC-ESI-MS (High performance liquid chromatography-electrospray tandem mass spectrometry) analyses showed presence of ferulic acid in all the five species. SC extract exhibited high radical scavenging (59.28 and 94.31 mg Trolox equivalent [TE]/g extract, DPPH (1,1-diphenyl-2-picrylhydrazyl) and ABTS (2,2'-azino-bis(3-ethylbenzothiazoline)-6-sulfonic acid), respectively) and reducing activity (161.44 and 113.62 mg TE/g extract, for CUPRAC (cupric reducing antioxidant capacity) and FRAP (ferric reducing antioxidant power), respectively). SM extract exhibited the highest cholinesterase's inhibitory action (3.82 and 4.76 mg galantamine equivalent/g extract, for acetyland butyrylcholinesterase, respectively). The extracts showed higher inhibition against alpha-glucosidase (7.32-11.99 mmol acarbose equivalent [ACAE]/g extract) compared to alpha-amylase (0.51-0.55 mmol ACAE/g extract). SC extract was the most active (137.54 mg kojic acid equivalent/g extract) tyrosinase inhibitor and FV extract (113.75 mg Orlistat equivalent/g) the best lipase inhibitor. SM extract showed potent antibacterial effect against B. cereus (MIC (minimum inhibitory concentration) 0.180 mg/mL), P. mirabilis (MIC 0.180 mg/mL), M. flavus (MIC 0.560 mg/mL), P. aeruginosa (MIC 0.275 mg/mL), and S. typhimurium (MIC 1.500 mg/mL). FV extract (MIC 0.140 mg/mL) suppressed A. fumigates growth. Cytotoxicity was assessed on murine macrophage (RAW 264.7), human embryonic kidney (HEK 293), and human hepatocellular carcinoma (HepG2) cell lines. FV (60.3%) and SM (57.4%) showed the highest reduction on RAW 264.7 cellular viability, whereas SM (74.1%) showed toxicity against HepG2. This study supports that the Apiaceae species could be considered as promising candidates for the development of novel pharmacophores for the management of several human ailments.
- Temperature effects on growth, metabolome, lipidic profile and photosynthetic pigment content of Microglena antarctica (chlorophyceae): a comprehensive analysisPublication . Trentin, Riccardo; Moschin, Emanuela; Custódio, Luísa; Moro, IsabellaAntarctic microalgae have evolved a wide range of adaptations to survive at extreme environmental conditions. This study aimed to explore the physiological and biochemical processes occurring in Microglena antarctica (Chlorophyceae) in response to changes in temperature. M. antarctica cultivated at three distinct temperatures (4 degrees C, 8 degrees C and 16 degrees C) exhibited variations in growth patterns, metabolomes, fatty acid methyl esters (FAMEs) profile and photosynthetic pigment concentrations. Our results highlighted a decrease in growth at 16 degrees C, confirming the cryophilic nature of this species. The growth rates at the exponential phase were observed to decrease progressively with an initial rate of (0.29 +/- 0.05 d(-1)) at the culturing temperature of 4 degrees C, followed by 8 degrees C (0.24 +/- 0.09 d(-1)), and further reduction at 16 degrees C (0.16 +/- 0.05 d(-1)). An integrative untargeted metabolomics approach combining mass spectral libraries and novel in-silico tools was employed to improve feature annotation and to provide additional information on features chemical classes. Significant differences in M. antarctica annotated compounds, chemical classes and whole metabolomes were observed among 4, 8 and 16 degrees C. Finally, targeted analyses were performed to evaluate changes in lipid profiles and photosynthetic pigment content. Higher percentages of polyunsaturated fatty acids (PUFAs) were observed at 4 and 8 degrees C, approximately 65.00 % of total FAMEs, and decreased to 60.71 % at 16 degrees C. Monounsaturated fatty acids (MUFAs) significantly increased at 16 degrees C, reaching up to 10.96 % of total FAMEs, in contrast to 4 degrees C and 8 degrees C, where the content of MUFAs was around 5.00 %. Additionally, chlorophyll a and carotenoid content increased by 50-100 % at 16 degrees C compared to lower temperatures. The present work highlights temperature-related responses in M. antarctica biochemical profile, combining untargeted and targeted approaches, and physiology, by growth analysis.
- First report of the nutritional profile and antioxidant potential of Holothuria arguinensis, a new resource for aquaculture in EuropePublication . Roggatz, Christina C.; Gonzalez-Wanguemert, Mercedes; Pereira, Hugo; Rodrigues, Maria Joao; F. G. M. Silva, Manuela; Barreira, Luísa; Varela, João; Custódio, LuísaThis work reports for the first time the nutritional profile and antioxidant potential of the edible sea cucumber Holothuria arguinensis from the North-eastern Atlantic. H. arguinensis has high levels of protein, with the amino acids profile dominated by alanine, glycine and proline and low lysine/arginine ratios. Its carbohydrate and energetic contents are also low as well as the total lipid levels, although its lipid profile is rich in polyunsaturated fatty acids (PUFA), especially arachidonic, eicosapentaenoic and docosahexaenoic acids. In addition, H. arguinensis has high levels of calcium. The water and ethanol extracts show ability to scavenge free radicals and to chelate copper and iron ions. Our results indicate that H. arguinensis has a balanced nutritional quality suitable for human consumption. In addition, it contains compounds with antioxidant potential; thus its intake can contribute for a healthy and well-balanced diet.