37 results on '"Lima, Elisabete"'
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2. Biological activities of organic extracts and specialized metabolites from different parts of Cryptomeria japonica (Cupressaceae) – A critical review
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Lima, Ana, Arruda, Filipe, Janeiro, Alexandre, Medeiros, Jorge, Baptista, José, Madruga, João, and Lima, Elisabete
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- 2023
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3. Essential Oil Composition and Anti-Cholinesterase Properties of Cryptomeria japonica Foliage Harvested in São Miguel Island (Azores) in Two Different Seasons.
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Rodrigues, Tânia, Lima, Ana, Wortham, Tanner, Arruda, Filipe, Janeiro, Alexandre, Baptista, José, and Lima, Elisabete
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FOREST biomass ,CRYPTOMERIA japonica ,ARTEMIA ,ESSENTIAL oils ,SPRING - Abstract
The Azorean Cryptomeria japonica forest operations and wood industry generate considerable foliage biomass residues that are used for local essential oil (EO) production. However, research on seasonal variation of C. japonica EO remains scarce. In this study, the EOs from fresh Azorean C. japonica foliage (Az–CJF) collected in autumn (Aut) and spring (Spr) were obtained via hydrodistillation and investigated for their physical properties, yield, chemical composition, and bioactivities. Both EOs presented a strong odor, a yellowish color, a density around 0.9 g·mL
−1 , and similar yields (approximately 1% v/w, dry matter). Nevertheless, the GC–MS analyses showed a decrease in monoterpene hydrocarbons (MH) and an increase in oxygenated sesquiterpenes (OS) contents in Spr–EO compared with Aut–EO (16% vs. 35% for MH and 45% vs. 31% for OS, respectively). In addition, the predominant components were kaur-16-ene (23%) for Spr–EO and phyllocladene (19%) for Aut–EO, revealing that both EOs were rich in diterpene hydrocarbons (29% vs. 26%). Concerning its toxicity against brine shrimp, a low mortality (0–38%) was observed at a concentration range of 100–180 μg·mL−1 . Regarding the anti-cholinesterase properties, both EOs were inactive against acetylcholinesterase but showed anti-butyrylcholinesterase activity superior to (–)-α-pinene, a major compound of Az–CJF EO (IC50 values: 84, 148, and 648 μg·mL−1 for Spr–EO, Aut–EO, and α-pinene, respectively). Overall, the results indicate the potential benefit of both seasonal EOs in Alzheimer's disease treatment. In conclusion, this study demonstrated that season strongly influences the Az–CJF EO quantitative composition and thus its bioactivity, aiding in the selection of the most high-quality raw materials for use in Azorean C. japonica EO aromatherapy industry. [ABSTRACT FROM AUTHOR] more...- Published
- 2024
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4. Anticholinesterase and Anti-Inflammatory Activities of the Essential Oils of Sawdust and Resin-Rich Bark from Azorean Cryptomeria japonica (Cupressaceae): In Vitro and In Silico Studies.
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Lima, Ana, Arruda, Filipe, Frias, Jorge, Wortham, Tanner, Janeiro, Alexandre, Rodrigues, Tânia, Baptista, José, and Lima, Elisabete
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CRYPTOMERIA japonica ,ALZHEIMER'S disease ,ESSENTIAL oils ,ARTEMIA ,ANTI-inflammatory agents ,ACETYLCHOLINESTERASE - Abstract
Alzheimer's disease (AD), a multifactorial neurodegenerative disorder characterized by severe cognitive impairment, affects millions of people worldwide. However, AD therapy remains limited and mainly symptomatic-focused, with acetylcholinesterase (AChE) inhibitors being the major available drugs. Thus, AD is considered by the WHO as a disorder of public health priority. Among several strategies that have been identified to combat AD, the use of natural multi-target drug ligands (MTDLs) appears to be a promising approach. In this context, we previously found that the essential oils (EOs), obtained via hydrodistillation, from Azorean Cryptomeria japonica sawdust (CJS) and resin-rich bark (CJRRB) were able to exert antioxidant activity via different mechanisms of action. Therefore, in the present work, these EOs were screened for their (i) in vitro anti-AChE and anti-butyrylcholinesterase (BChE) activities, evaluated by a modified Ellman's assay; (ii) in vitro anti-inflammatory potential, using the albumin denaturation method; and (iii) toxicity against Artemia salina. The CJRRB–EO exhibited both anti-AChE and anti-BChE activities (IC
50 : 1935 and 600 µg/mL, respectively), whereas the CJS–EO only displayed anti-BChE activity, but it was 3.77-fold higher than that of the CJRRB–EO. Molecular docking suggested that α-pinene and ferruginol compounds contributed to the anti-AChE and anti-BChE activities, respectively. Moreover, the anti-inflammatory activity of the CJS–EO, the CJRRB–EO, and diclofenac was 51%, 70%, and 59% (at a concentration of only 2.21 μg/mL), respectively, with the latter two presenting comparable activity. Concerning the EOs' potential toxicity, the CJRRB–EO exhibited a lower effect than the CJS–EO (LC50 : 313 and 73 µg/mL, respectively). Overall, the EOs from C. japonica biomass residues, chiefly the CJRRB–EO, displayed antioxidant, anticholinesterase, and anti-inflammatory activities in a concentration-dependent manner. These properties demonstrate that these residues may be suitable natural MTDLs for AD complementary therapy when administered through aromatherapy, or, alternatively, could serve as low-cost sources of valuable ingredients, such as α-pinene. [ABSTRACT FROM AUTHOR] more...- Published
- 2024
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5. Variability of antioxidant properties, catechins, caffeine, L-theanine and other amino acids in different plant parts of Azorean Camellia sinensis
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Paiva, Lisete, Lima, Elisabete, Motta, Madalena, Marcone, Massimo, and Baptista, José
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- 2020
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6. Sequential Separation of Essential Oil Components during Hydrodistillation of Fresh Foliage from Azorean Cryptomeria japonica (Cupressaceae): Effects on Antibacterial, Antifungal, and Free Radical Scavenging Activities.
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Arruda, Filipe, Lima, Ana, Wortham, Tanner, Janeiro, Alexandre, Rodrigues, Tânia, Baptista, José, Rosa, José S., and Lima, Elisabete
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MICROCOCCUS luteus ,CRYPTOMERIA japonica ,ESSENTIAL oils ,GRAM-positive bacteria ,CIRCULAR economy ,PHYTOPATHOGENIC bacteria - Abstract
Cryptomeria japonica wood industry generates large amounts of foliage biomass residues. Due to the increasing applications and markets for essential oils (EOs), fresh Azorean C. japonica foliage (Az–CJF) residues are used for local EO production. Hydrodistillation (HD), a common process for obtaining EOs, also provides the possibility to fractionate them. Thus, this study evaluated the in vitro antimicrobial and antioxidant activities of six Az–CJF EO fractions (Frs. 1–6), collected at sequential HD timeframes (HDTs: 0–2, 2–10, 10–30, 30–60, 60–120, and 120–240 min), in comparison to the crude EO, obtained from a non-fractionated HD (0–240 min HDT). Antimicrobial activities were assessed via disc diffusion method against seven bacteria (foodborne and/or human pathogens) and two Penicillium spp. (phytopathogenic fungi), and antioxidant activity was estimated using DPPH and ABTS assays. Concerning the antibacterial activity, all the EO samples were effective only toward Gram-positive bacteria. Fractions 1–3 (<30 min HDT) were the most active, with growth inhibition zones (GIZ) of 7.0–23.3 mm (1.4–2.2 times higher than those of the crude EO), being Bacillus spp. (B. licheniformis and B. subtilis) the most sensitive, followed by Staphylococcus aureus and Micrococcus luteus. Regarding the antifungal activity, Frs. 1–3 also displayed the best activities, but only against P. italicum (GIZ around 9.0 mm), while the crude EO showed no antifungal activity. Overall, the best antimicrobial properties of Frs. 1–3 could be attributed, at least in part, to their highest content in α-pinene and bornyl acetate. On the other hand, Frs. 4–6 (>30 min HDT) exhibited the strongest antioxidant activities (EC
50 values: 1.5–2.3 and 1.0–1.7 mg mL−1 for DPPH and ABTS, respectively), being at least 1.3-fold higher than those of the crude EO. The presence of nezukol, elemol, and eudesmol isomers could strongly contribute to the best free radical scavenging properties of Frs. 4–6. In conclusion, HD was found to be an efficient process for obtaining new Az–CJF EO fractions with variable and enhanced bioactivities due to their differential composition, as assessed using GC–MS. Hence, these findings could contribute to increasing the commercial potential of the C. japonica EO industry, namely, the Fr2 and Fr6, which presented the most significant activities and can have potential applications in the food, medical, and agriculture sectors. [ABSTRACT FROM AUTHOR] more...- Published
- 2024
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7. Chemical Compositions and In Vitro Antioxidant Activities of the Essential Oils of Sawdust and Resin-Rich Bark from Azorean Cryptomeria japonica (Cupressaceae).
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Lima, Ana, Arruda, Filipe, Wortham, Tanner, Janeiro, Alexandre, Rodrigues, Tânia, Baptista, José, and Lima, Elisabete
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CRYPTOMERIA japonica ,ESSENTIAL oils ,MONOTERPENES ,WOOD waste ,CUPRESSACEAE ,SESQUITERPENES - Abstract
In the Azores archipelago (Portugal), forest operations and wood industry generate large amounts of Cryptomeria japonica biomass residues (CJBR), which can be used to produce valuable essential oils (EOs). In this study, we evaluated the chemical composition and antioxidant activities of EOs from Azorean C. japonica sawdust (CJS) and resin-rich bark (CJRRB). The CJS and CJRRB EOs, obtained via hydrodistillation, showed different yield values (0.27% vs. 0.80% v/w, dry weight) and also different chemical profiles, as assessed using GC/MS. A total of 64 and 85 components were identified in CJS and CJRRB EOs, representing 95.7% and 96.9% of the total composition, respectively. The major components in CJS EO were oxygenated sesquiterpenes (mainly α+β-eudesmol, 1-epicubenol, and cubebol), while in CJRRB EO, the major components were monoterpene hydrocarbons, including α-pinene, δ-3-carene, and limonene (66.6% vs. 6.4% for oxygenated sesquiterpenes and 0% vs. 64% for monoterpene hydrocarbons, respectively). Antioxidant activity was estimated using (i) two radical-based assays, 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azinobis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical scavenging activity, and (ii) a lipid model assay, β-carotene-linoleic acid bleaching activity (BCBA). Both CJS and CJRRB EOs exhibited concentration-dependent antioxidant activities, and their DPPH, ABTS, and BCBA EC
50 values were 1107 vs. 1275 µg/mL, 260 vs. 498 µg/mL, and 1764 vs. 662 µg/mL, respectively. The results indicate that both EOs were able to exert antioxidant activity via different mechanisms of action. Therefore, Azorean CJS and CJRRB may be sustainable sources for antioxidant compounds. This study expands the chemical and biological knowledge of CJBR EOs and, consequently, adds more value to the C. japonica EO industry. [ABSTRACT FROM AUTHOR] more...- Published
- 2024
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8. Terpenes as Potential Anti-Alzheimer's Disease Agents.
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Lima, Elisabete and Medeiros, Jorge
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TERPENES ,ALZHEIMER'S disease ,METABOLITES ,SESSILE organisms ,NEUROFIBRILLARY tangles ,AMYLOID plaque - Abstract
Alzheimer's disease (AD), a slowly progressive neurodegenerative disorder, is the main cause of dementia worldwide. However, currently, the approved drugs to combat AD are effective only in treating its symptoms. In fact, an efficacious treatment for this complex and multifactorial disorder remains to be discovered, demanding the urgent development of new therapeutic approaches for the disease, such as the use of bioactive secondary metabolites (SMs) from natural sources. Sessile organisms, like plants, are unable to escape from adverse environmental conditions and must therefore create their own defense. Their main defense strategy is chemical defense that includes the production of an enormously diverse array of bioactive SMs, such as terpenes and their derivatives. This largest and most diverse group of plant SMs also provide the treatment of several diseases due to their broad-spectrum bioactivities, for example, anticancer, antioxidant, and anti-inflammatory properties. Thus, the evaluation of the neuroprotective potential of terpenes is imperative. It is known that the major AD clinical indications (CIs) are extracellular senile plaques of amyloid-β (Aβ) protein, intracellular hyperphosphorylated tau (τ) neurofibrillary tangles (NFTs), uncommon neuroinflammatory response, oxidative stress, and synaptic and neuronal dysfunction. Therefore, terpenes that may decrease these CIs might be used for AD treatment. Surely, terpenes targeting more than one AD pathogenic mechanism, multi-target drug ligands (MTDLs), have the potential to become a leading AD treatment. Thus, this review analyzes, for each CI, the scaffolds of the selected terpenes leading to the highest activity. [ABSTRACT FROM AUTHOR] more...
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- 2024
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9. Variations in Essential Oil Biological Activities of Female Cones at Different Developmental Stages from Azorean Cryptomeria japonica (Thunb. ex L.f.) D. Don (Cupressaceae).
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Janeiro, Alexandre, Lima, Ana, Arruda, Filipe, Wortham, Tanner, Rodrigues, Tânia, Baptista, José, and Lima, Elisabete
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CRYPTOMERIA japonica ,ESSENTIAL oils ,CONES ,CUPRESSACEAE ,STAPHYLOCOCCUS epidermidis ,PENICILLIUM ,FRACTIONS ,LAMINARIA - Abstract
In the Azores Archipelago, Cryptomeria japonica is, currently, the most cultivated forestry tree for timber production, landscaping, and gardening, generating large amounts of foliage waste that is used for local essential oils (EOs) production. However, the existing literature on the biological potential of EOs from different C. japonica foliage parts, such as female cones (FC), remains limited. Thus, in the present study, EOs extracted by hydrodistillation from Azorean C. japonica immature and mature FC (IFC and MFC), as well as some major EO components, were screened for their: (i) antioxidant capacity, evaluated by DPPH free-radical-scavenging activity (FRSA) and β-carotene-linoleic acid bleaching activity (BCBA), (ii) antimicrobial activities, assessed by the disc diffusion method against eight bacteria and one fungus, and (iii) toxicity against Artemia salina. Among both FC EO samples, the IFC EO exhibited the best DPPH–FRSA, BCBA, and growth inhibitory activity against Staphylococcus aureus, Staphylococcus epidermidis, Bacillus subtilis, and Penicillium italicum, as well as a slightly increased toxic potential, due to their differential compositions, as assessed by GC–MS analysis. Thus, the FC's maturation process decreased their EOs' bioactivities. In conclusion, this finding could help in determining the optimal developmental stage for enhancing the antioxidant and antimicrobial compounds content in FC EOs. In turn, this contributes to increasing the commercial potential of C. japonica's EO industry. [ABSTRACT FROM AUTHOR] more...
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- 2024
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10. Health-promoting ingredients from four selected Azorean macroalgae
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Paiva, Lisete, Lima, Elisabete, Neto, Ana Isabel, Marcone, Massimo, and Baptista, José
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- 2016
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11. Isolation and characterization of angiotensin I-converting enzyme (ACE) inhibitory peptides from Ulva rigida C. Agardh protein hydrolysate
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Paiva, Lisete, Lima, Elisabete, Neto, Ana Isabel, and Baptista, José
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- 2016
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12. Essential Oils from Azorean Cryptomeria japonica Female Cones at Different Developmental Stages: Variations in the Yields and Chemical Compositions.
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Janeiro, Alexandre, Lima, Ana, Arruda, Filipe, Wortham, Tanner, Rodrigues, Tânia, Baptista, José, and Lima, Elisabete
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ESSENTIAL oils ,CRYPTOMERIA japonica ,CHEMICAL yield ,MONOTERPENES ,TERPENES ,CONES ,SESQUITERPENES - Abstract
Cryptomeria japonica (Thunb. ex L.f.) D. Don (Cupressaceae) is widely cultivated in the Azores archipelago (Portugal) for landscaping and timber production, generating a huge amount of biomass residues. Among these, female cones (FC) emerge as a source of particularly valuable essential oils (EOs), namely, as promising broad-spectrum antimicrobial agents. However, phytochemical research on C. japonica FC EOs remains scarce. This study evaluated the EO yields and chemical compositions of immature and mature FC (IFC and MFC) from the same batch of Azorean C. japonica. IFC and MFC EOs, obtained via hydrodistillation, presented different yields (0.72% vs. 1.12% w/w, dry weight), and their composition, determined via gas chromatography/mass spectroscopy, revealed that the monoterpenes class was dominant (51.84% vs. 69.13%), followed by the sesquiterpenes (36.44% vs. 26.28%) and diterpenes (10.96% vs. 3.03%) classes. However, the correspondent oxygen-containing terpenes classes were 1.5–2.0 times higher in IFC. Thus, the maturation process revealed an increase in EO yield and α-pinene content (19.5% vs. 41.3%) but a decrease in other important bioactive terpenes/terpenoids (terpinen-4-ol, bornyl acetate, elemol, γ-eudesmol, phyllocladene, and nezukol) content. In conclusion, IFC and MFC EOs, due to their unique composition, may have differential commercial applications and, consequently, contribute to increasing the commercial potential of C. japonica's EO industry. [ABSTRACT FROM AUTHOR] more...
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- 2024
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13. Value of off-season fresh Camellia sinensis leaves. Antiradical activity, total phenolics content and catechin profiles
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Baptista, José, Lima, Elisabete, Paiva, Lisete, and Castro, Ana R.
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- 2014
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14. HPLC–UV–ESI-MS analysis of phenolic compounds and antioxidant properties of Hypericum undulatum shoot cultures and wild-growing plants
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Rainha, Nuno, Koci, Kamila, Coelho, Ana Varela, Lima, Elisabete, Baptista, José, and Fernandes-Ferreira, Manuel
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- 2013
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15. Sequential Separation of Essential Oil Components during Hydrodistillation of Azorean Cryptomeria japonica Foliage: Effects on Yield, Physical Properties, and Chemical Composition.
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Arruda, Filipe, Lima, Ana, Wortham, Tanner, Janeiro, Alexandre, Rodrigues, Tânia, Baptista, José, Rosa, José S., and Lima, Elisabete
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CRYPTOMERIA japonica ,ESSENTIAL oils ,MONOTERPENES ,OPERATING costs ,REGRESSION analysis ,SESQUITERPENES - Abstract
The hydrodistillation (HD) process is used to obtain and fractionate essential oils (EOs). In this study, we aimed to evaluate, for the first time, the effects of six different HD timeframes (HDTs: 0–2, 2–10, 10–30, 30–60, 60–120, and 120–240 min) on the yield, physical properties, and chemical profile of Azorean Cryptomeria japonica foliage (Az–CJF) EO. An Az–CJF EO obtained by a typical HD over 4 h was used as a control sample, yielding 0.82%, w/fresh weight (f.w.), and containing eighty-nine components, as determined by GC–MS. The EO fraction yield revealed a narrow range (0.06–0.18%, w/f.w.), with ca. 50% obtained within the first hour. Monoterpene hydrocarbons dominated in Fr1 and Fr2 (92 and 45%, respectively, mainly α-pinene) while oxygen-containing sesquiterpenes prevailed in Frs. 3–6 (42–62%, mainly elemol and eudesmol isomers). Furthermore, Fr2 and Fr3 were the richest in oxygen-containing monoterpenes (9 and 7%, respectively, mainly bornyl acetate) and in sesquiterpene hydrocarbons (6 and 5%, respectively, mainly δ-cadinene), while Fr4 and Fr5 had higher amounts of diterpene hydrocarbons (ca. 22% both, mainly phyllocladene) and Fr6 exhibited the highest oxygen-containing diterpenes content (4%, mainly nezukol). In addition, regression models were established to predict EO yield, HD rate, and composition (major components) for a given HDT. As a result of this study, specific EO fractions can now be targeted in Az–CJF EO by adjusting the HDT. Hence, these findings can help reduce distillation time and, thus, operating costs associated with the HD process. It can also meet specific market demands due to the differential composition of the obtained EO fractions. In turn, this contributes to increasing the commercial potential of C. japonica EO. [ABSTRACT FROM AUTHOR] more...
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- 2023
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16. Essential Oils from Different Parts of Azorean Cryptomeria japonica (Thunb. ex L.f.) D. Don (Cupressaceae): Comparison of the Yields, Chemical Compositions, and Biological Properties.
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Lima, Ana, Arruda, Filipe, Janeiro, Alexandre, Rodrigues, Tânia, Baptista, José, Figueiredo, Ana Cristina, and Lima, Elisabete
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ESSENTIAL oils ,CRYPTOMERIA japonica ,CUPRESSACEAE ,ARTEMIA ,GAS chromatography/Mass spectrometry (GC-MS) ,DITERPENES ,MONOTERPENES ,PENICILLIUM chrysogenum - Abstract
Azorean Cryptomeria japonica is widely used for local wood production, generating large amounts of aerial-part biomass residues that can be a sustainable source of value-added bioproducts. This comparative study aimed (i) to determine the yield and chemical profile of the essential oils (EOs) extracted by hydrodistillation from Azorean C. japonica foliage, leaves, male cones (MCs), and female cones (FCs), and (ii) to investigate the antimicrobial and brine shrimp lethality (BSL) effects of the obtained EOs and some major components. The EOs yield revealed a wide range (ca. 1–3%, w/d.w.) and their chemical composition, analysed by GC–MS and GC–FID, showed the presence of seventy-one components. Monoterpene hydrocarbons (38–71%) dominated in all the studied EOs, mainly α-pinene (17–45% of total EOs), decreasing as follows: cone EOs > leaf EOs > foliage EOs. Oxygen-containing monoterpenes (mainly terpinen-4-ol) also dominated in cone EOs. Contrariwise, oxygen-containing sesquiterpenes (mainly elemol) and diterpene hydrocarbons (mainly phyllocladene) dominated in foliage/leaf EOs. The studied EOs exhibited activity against Gram-positive bacteria but no activity against Gram-negative bacteria. A similar trend was displayed by α-pinene. Only the cone EOs showed antifungal activity against Penicillium chrysogenum, but this was significantly lower than those of α-pinene and terpinen-4-ol. Moreover, FC EO should also be considered for further investigation due to its high toxicity on BSL bioassay. In conclusion, this study demonstrated the variability of yield, chemical profile, and bioactivities in the EOs from different parts of the Azorean C. japonica, expanding the knowledge of the potentialities of C. japonica aerial-part EOs, particularly the ones from the cone samples. [ABSTRACT FROM AUTHOR] more...
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- 2023
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17. Flavonoids as Promising Multitarget Agents in Alzheimer's Disease Therapy.
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Lima, Elisabete, Rauter, Amélia P., and Medeiros, Jorge
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ALZHEIMER'S disease ,FLAVONOIDS ,BLOOD-brain barrier ,NEUROFIBRILLARY tangles ,AMYLOID plaque ,TISSUE scaffolds ,CLINICAL indications - Abstract
The increase in the occurrence of the multifactorial Alzheimer's disease (AD) demands an urgent effort towards the development of effective anti-AD agents, such as the multitarget-directed ligands (MTDLs). In fact, AD is a genetic and an environmental disease, involving a diversity of etiopathogenic processes, and there is not yet a successful AD treatment. The major AD clinical indications (CIs) are extracellular amyloid plaques, intracellular neurofibrillary tangles (NFTs), abnormal inflammatory response, and neuron apoptosis and death caused by oxidative stress. The discovery of neuroprotective natural products, presenting good oral bioavailability, ability to cross the blood-brain barrier (BBB) and safety profile, is indeed a necessity, and some flavonoids are in clinical trials for AD treatment. In this review, the several flavonoids from natural sources that have shown activity on mechanisms associated with AD are presented. Although several reviews have been presented in the last few years, the main objective of this review is to recognize and discuss, for each CI, the scaffolds leading to the highest activity and so to attempt to achieve molecules targeting more than one CI, the MTDLs, which are potential leads for AD treatment. In conclusion, the most active flavonoids against several CIs of AD are flavanols and flavonols, which have a planar scaffold and structures presenting hydroxy groups at C5 and C7 on ring A and at C4′ of ring B. Thus, molecules linking flavanols to flavonols, with hydroxy groups at C5 and C7 on ring A and at C4′ of ring B, are also promising against CIs of AD and potential anti-AD agents. [ABSTRACT FROM AUTHOR] more...
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- 2023
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18. Essential Oil Variability of Azorean Cryptomeria japonica Leaves under Different Distillation Methods, Part 2: Molluscicidal Activity and Brine Shrimp Lethality.
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Arruda, Filipe, Lima, Ana, Oliveira, Luísa, Rodrigues, Tânia, Janeiro, Alexandre, Rosa, José S., and Lima, Elisabete
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CRYPTOMERIA japonica ,ESSENTIAL oils ,ARTEMIA ,DISTILLATION ,WOOD waste ,FORESTS & forestry ,NATURAL products - Abstract
This study reports on the in vivo molluscicidal activity and Artemia salina lethality of Azorean Cryptomeria japonica leaf (CJL) essential oils (EOs) obtained by hydrodistillation (HD) and water-steam distillation (WSD) techniques, especially in light of the recent focus on the use of forestry and wood industry residues in a sustainable world economy. Molluscicidal activity was performed during several life stages of Radix peregra by the immersion method, under laboratory conditions. A first screening through a single-dose bioassay revealed that both EOs were highly active towards eggs, juveniles and adult snails (ca. 100% mortality). Concentration- and time-toxicity assays were carried out only on adult snails to determine the lethal parameters (LC
50;90 and LT50;90 ). The LC50 values were 33 and 62 µg/mL for EO–WSD and EO–HD, respectively, after 48 h. The LT50 of EO–WSD required only 21 h for both 16 h and continous exposure periods, while that of EO–HD was slighty superior (21.8–25.6 h). Although not significant, EO–WSD was also slightly more toxic against A. salina than EO–HD (LC50 = 98 and 115 µg/mL after 24 h, respectively). In conclusion, Azorean CJL EOs, which are rich in α-pinene (mostly EO–WSD), have huge potential to be used as safe raw materials for the development of natural molluscicide products to control snails responsible for transmitting fascioliasis. [ABSTRACT FROM AUTHOR] more...- Published
- 2023
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19. Nutritional value of selected macroalgae
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Patarra, Rita Ferreira, Paiva, Lisete, Neto, Ana Isabel, Lima, Elisabete, and Baptista, José
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- 2011
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20. Investigation of the Azorean Camellia sinensis Processing Conditions to Maximize the Theaflavin 3,3′-di- O -Gallate Content as a Potential Antiviral Compound.
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Paiva, Lisete, Lima, Elisabete, Motta, Madalena, Marcone, Massimo, and Baptista, José
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TEA ,TEA plantations ,VIRAL proteins ,ENZYME inhibitors ,VIRAL replication - Abstract
The molecular constituents of Camellia sinensis, in particular epigallocatechin-3-O-gallate (EGCG) and, more remarkably, the galloylated theaflavins, mainly theaflavin-3,3′-di-O-gallate (TF-3,3′-DG), have been reported to inhibit SARS-CoV-2 3-chymotrypsin-like protease (3CL
pro ), an enzyme required for the cleavage of its polyproteins, to produce vital individual functional proteins for viral cell replication. Our results for total catechin content revealed the values of 174.72, 200.90, and 211.75 mg/g dry weight (DW) in spring, and the values of 183.59, 191.36, and 215.09 mg/g DW in summer, for tea plantation zones 1, 2, and 3, respectively. For the TF-3,3′-DG content, the values of 2.68, 1.13, and 3.72 mg/g DW were observed in spring, and the values of 3.78, 2.06, and 8.91 mg/g DW in summer for zones 1, 2, and 3, respectively. In the same zone, different contents of TF-3,3′-DG were observed across plucking months of April, June, and August, with values of 1.13, 2.77, and 4.18 mg/g DW, respectively, showing higher values in summer. Different values of TF-3,3′-DG contents were also observed in the same tea plantation zone but from different plant parts, revealing higher values in the bud and the first and second leaves (3.62 mg/g DW) and lower values in the third and fourth leaves (1.14 mg/g DW). The TF-3,3′-DG content increased from 3.31 to 4.98 mg/g DW with increased fermentation time from 1 to 3 h, respectively, and increased for lower temperature and longer fermentation time. The aim of this study was to investigate the processing conditions that lead to maximum TF-3,3′-DG content and, given its potential impact as an inhibitor of the 3CLpro enzyme, to create a novel antiviral Azorean black tea. [ABSTRACT FROM AUTHOR] more...- Published
- 2022
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21. Essential Oil Variability of Azorean Cryptomeria japonica Leaves under Different Distillation Methods, Part 1: Color, Yield and Chemical Composition Analysis.
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Arruda, Filipe, Rosa, José S., Rodrigues, Ana, Oliveira, Luísa, Lima, Ana, Barroso, José G., and Lima, Elisabete
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ESSENTIAL oils ,CRYPTOMERIA japonica ,ANALYTICAL chemistry ,CHEMICAL yield ,DISTILLATION ,MONOTERPENES - Abstract
This study mainly deals with the effect of hydrodistillation (HD) and water-steam distillation (WSD) methods on the color, yield, and chemical profile of the essential oil (EO) from Cryptomeria japonica fresh leaves from São Miguel Island (Azores Archipelago, Portugal). The yields of EO–HD (pale-yellowish) and EO–WSD (colorless) samples were 1.21% and 0.45% (v/w), respectively. The GC–FID, GC–MS, and
13 C-NMR analyses of EO–HD vs. EO–WSD revealed (i) a high-content of monoterpenes (72.8% vs. 86.7%), mainly α-pinene (34.5% vs. 46.4%) and sabinene (20.2% vs. 11.6%), and oxygenated mono- and sesquiterpenes (20.2% vs. 9.6%); (ii) similar sesquiterpene (1.6% vs. 1.6%), β-myrcene (5.9% vs. 5.8%), and camphene (3.5% vs. 3.8%) contents; and (iii) significant differences in other classes/components: EO–HD is richer in oxygenated sesquiterpenes (17.1%, mainly elemol (10.4%) and α-eudesmol (3.4%)) and diterpenes (3%; mostly phyllocladene), while EO–WSD is richer in oxygenated monoterpenes (7.2%, mainly terpinen-4-ol (5.4%)), p-cymene (4.4%), and limonene (3.2%). Overall, the color, yield, and quantitative composition of the EO samples studied are strongly influenced by the distillation method. Nonetheless, this C. japonica leaf EO displayed a consistent α-pinene- and sabinene-rich composition. The same chemotype was found in a commercial Azorean C. japonica leaf EO sample, obtained by industrial steam distillation (SD), as well as in Corsica C. japonica leaf EO–HD. Furthermore, the bioactive composition of our EO samples revealed the potential to be used in green plant protection and in the medical, food, cosmetic, and household industries. [ABSTRACT FROM AUTHOR] more...- Published
- 2022
- Full Text
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22. Pentacyclic triterpenes from Euphorbia stygiana
- Author
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Lima, Elisabete M.C, Medeiros, Jorge M.R, and Davin, Laurence B
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- 2003
- Full Text
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23. Variations in Essential Oil Chemical Composition and Biological Activities of Cryptomeria japonica (Thunb. ex L.f.) D. Don from Different Geographical Origins—A Critical Review.
- Author
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Lima, Ana, Arruda, Filipe, Medeiros, Jorge, Baptista, José, Madruga, João, and Lima, Elisabete
- Abstract
The scientific community is paying increasing attention to plant waste valorization, and also to "greener" practices in the agriculture, food and cosmetic sectors. In this context, unused forest biomass (e.g., leaves, seed cones, branches/twigs, bark and sapwood) of Cryptomeria japonica, a commercially important tree throughout Asia and the Azores Archipelago (Portugal), is currently waste/by-products of wood processing that can be converted into eco-friendly and high added-value products, such as essential oils (EOs), with social, environmental and economic impacts. Plant-derived EOs are complex mixtures of metabolites, mostly terpenes and terpenoids, with valuable bioactivities (e.g., antioxidant, anti-inflammatory, anticancer, neuroprotective, antidepressant, antimicrobial, antiviral and pesticide), which can find applications in several industries, such as pharmaceutical, medical, aromatherapy, food, cosmetic, perfumery, household and agrochemical (e.g., biopesticides), with manifold approaches. The EOs components are also of value for taxonomic investigations. It is known that the variation in EOs chemical composition and, consequently, in their biological activities and commercial use, is due to different exogenous and endogenous factors that can lead to ecotypes or chemotypes in the same plant species. The present paper aims to provide an overview of the chemical composition, biological properties and proposals of valorization of C. japonica EO from several countries, and also to indicate gaps in the current knowledge. [ABSTRACT FROM AUTHOR] more...
- Published
- 2021
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24. Influence of Seasonal and Yearly Variation on Phenolic Profiles, Caffeine, and Antioxidant Activities of Green Tea (Camellia sinensis (L.) Kuntze) from Azores.
- Author
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Paiva, Lisete, Lima, Elisabete, Motta, Madalena, Marcone, Massimo, and Baptista, José
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GREEN tea ,TEA ,EPIGALLOCATECHIN gallate ,SEASONS ,PLANT phenols ,CLIMATE change ,CAFFEINE ,ANTIOXIDANTS - Abstract
This study compares the antioxidant properties (RSA
DPPH –DPPH radical scavenging activity, FRAP–ferric reducing activity power, and FIC–ferrous ion-chelating activity), the total phenolics (TP), total flavonoids (TF), and catechin profiles, as well as the caffeine content of Azorean Camellia sinensis green tea collected in seasons of two different years. The RSADPPH showed some variation between 2019 and 2020, and presented, in general, better results in 2020 as well as during the summer seasons. The FRAP was also noted to be at its highest in July and August of the two investigated years (6.64 and 6.40 µg/mL in 2019 and 5.85 and 5.46 µg/mL in 2020). According to FIC activity, the August 2019 sample exhibited the highest value (76.18%). The TP varied between 291.14 and 326.93 mg gallic acid equivalents (GAE)/g of dried extract (DE) in 2019 and between 300.25 and 320.58 mg GAE/g DE in 2020. Concerning the TF, the values varied between 51.85 and 67.93 mg rutin equivalents (RE)/g DE in 2019 and between 50.27 and 69.57 mg RE/g DE in 2020. Epicatechins derivatives, determined by HPLC, presented higher values in all samples from 2020 compared to 2019, and the same was observed for esterified catechins. The epigallocatechin-3-gallate content was also higher in all samples from 2020 (214.52–240.16 mg/g DE) compared to 2019 (140.91–210.83 mg/g DE). Regarding caffeine content (12.86–20.45 mg/g DE in 2019 and 13.19–29.35 mg/g DE in 2020), the samples from April and June exhibited similar values in both years. In general, green tea samples exhibited better results in 2020 than in 2019, with the exception of FIC activity, while the varied TP and TF contents in certain months reflect the impact of climatic variation on tea quality. [ABSTRACT FROM AUTHOR] more...- Published
- 2021
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25. Angiotensin I-Converting Enzyme (ACE) Inhibitory Activity, Antioxidant Properties, Phenolic Content and Amino Acid Profiles of Fucus spiralis L. Protein Hydrolysate Fractions.
- Author
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Paiva, Lisete, Lima, Elisabete, Neto, Ana Isabel, and Baptista, José
- Abstract
Food protein-derived hydrolysates with multi-bioactivities such as antihypertensive and antioxidant properties have recently received special attention since both activities can play significant roles in preventing cardiovascular diseases. This study reports, for the first time, the angiotensin I-converting enzyme (ACE)-inhibition and antioxidant properties of ultrafiltrate fractions (UF) with different molecular weight ranges (<1, 1-3 and =3 kDa) obtained from Fucus spiralis protein hydrolysate (FSPH) digested with cellulase-bromelain. The amino acids profile, recovery yield, protein, peptide and total phenolic contents of these FSPH-UF, and the in vitro digestibility of F. spiralis crude protein were also investigated. FSPH-UF =3 kDa presented remarkably higher ACE-inhibition, yield, peptide and polyphenolic (phlorotannins) contents. Antioxidant analysis showed that FSPH-UF <1 kDa and =3 kDa exhibited significantly higher scavenging of 2,2-diphenyl-1-picrylhydrazyl radical and ferrous ion-chelating (FIC) activity. FSPH-UF =3 kDa had also notably higher ferric reducing antioxidant power (FRAP). Strong correlations were observed between ACE-inhibition and antioxidant activities (FIC and FRAP). The results suggest that ACE-inhibition and antioxidant properties of FSPH-UF may be due to the bioactive peptides and polyphenols released during the enzymatic hydrolysis. In conclusion, this study shows the potential use of defined size FSPH-UF for the prevention/treatment of hypertension and/or oxidative stress-related diseases. [ABSTRACT FROM AUTHOR] more...
- Published
- 2017
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26. Nutritional and Functional Bioactivity Value of Selected Azorean Macroalgae: Ulva compressa, Ulva rigida, Gelidium microdon, and Pterocladiella capillacea.
- Author
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Paiva, Lisete, Lima, Elisabete, Neto, Ana Isabel, Marcone, Massimo, and Baptista, José
- Subjects
- *
COMPOSITION of algae , *BIOACTIVE compounds , *NUTRITIONAL value , *ULVA , *GELIDIUM , *FUNCTIONAL foods , *PROTEIN hydrolysates - Abstract
This study presents information on the biochemical composition (dry weight basis), nutritional aspects, and angiotensin I-converting enzyme (ACE) inhibitory properties of selected macroalgae ( Ulva compressa, Ulva rigida, Gelidium microdon, and Pterocladiella capillacea) from Azores. Moisture content was very high (83.2% to 90.0% of fresh weight). Total dietary fiber (33.7% to 41.0%) that presented a good balance of both soluble and insoluble fibers (15.5% to 19.2% and 18.2% to 21.8%, respectively) was the most abundant component in these macroalgae. Protein and ash (ranged from 15.7% to 23.4% and 10.7% to 20.7%, respectively) were the 2nd most abundant components in red and green macroalgae, respectively. Moderate soluble carbohydrate contents (14.5% to 19.8%) were found in all species. Lipid contents were low (1.0% to 4.3%), particularly in Ulva species (1.0% to 1.7%), but contained higher unsaturated fatty acids (FAs) (7.5% to 32.9% and 29.6% to 69.2% of total FA for monounsaturated fatty acid and polyunsaturated fatty acid groups, respectively) than saturated fatty acid (23.3% to 46.8% of total FA) contents. All the macroalgal proteins had high digestibility in vitro (82.2% to 89.4%, relatively to sodium caseinate), contained high quantity of essential amino acids (45.3% to 58.1% of total amino acids), but in different proportions, and were rich in aspartic and glutamic acids that together account for 17.2% to 36.2% of the total amino acids. These results suggested that regular consumption of the selected macroalgae may improve human health and revealed that they can be used for producing food supplements for human and animal nutrition and/or pharmaceuticals with potential effect on the regional economy. Furthermore, the ACE-inhibitory IC50 values of 0.095 to 0.695 mg/mL for the <1 kDa protein hydrolysate fraction revealed a potential impact on hypertension disorder. [ABSTRACT FROM AUTHOR] more...
- Published
- 2017
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27. Angiotensin I-converting enzyme (ACE) inhibitory activity of Fucus spiralis macroalgae and influence of the extracts storage temperature—A short report.
- Author
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Paiva, Lisete, Lima, Elisabete, Neto, Ana Isabel, and Baptista, José
- Subjects
- *
ACE inhibitors , *FUCUS , *PHLOROGLUCINOL , *PLANT extracts , *PHLOROTANNINS , *PLANT polyphenols - Abstract
Recently, increasing attention has been paid to the marine algae as a natural source of novel angiotensin-I converting enzyme (ACE) inhibitors, such as the phlorotannins that are the predominant polyphenols in brown algae. This study reports, for the first time, the ACE inhibition of methanol extract/fractions from Azorean brown algae Fucus spiralis (Fs) determined by HPLC-UV method, their total phenolic content (TPC) quantified as phloroglucinol equivalents (PE) and the effect of the Fs dry powder methanol extracts (Fs-DME) storage temperature on ACE inhibition. The results indicate that the ACE inhibition of Fs-DME decreased by 28.8% and 78.2% when stored during 15 days at −80 °C and −13 °C, respectively, as compared with the activity of Fs-DME at a refrigerated temperature of 6 °C and assayed immediately after extraction that showed a value of 80.1 ± 2.1%. This Fs-DME sample was fractionated by ultrafiltration membranes into three molecular weight ranges (<1 kDa, 1–3 kDa and >3 kDa), presenting the fraction >3 kDa remarkably high ACE inhibition (88.8 ± 2.4%), TPC value (156.6 ± 1.4 mg PE/g of dry weight fraction) and yield. Furthermore, chromatographic and spectrophotometric analyses corroborate that phenolic compounds were present in Fs methanol extract/fractions, and also revealed that phloroglucinol occurs in Fs. The results seem to suggest that Azorean Fs can be a source of powerful ACE-inhibitory phlorotannins with potential impact on public health, particularly on hypertensive patients. [ABSTRACT FROM AUTHOR] more...
- Published
- 2016
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28. Edible Azorean macroalgae as source of rich nutrients with impact on human health.
- Author
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Paiva, Lisete, Lima, Elisabete, Ferreira Patarra, Rita, Neto, Ana Isabel, and Baptista, José
- Subjects
- *
ALGAE as food , *PLANT nutrients , *ISLANDS , *ALGAL proteins , *DIETARY carbohydrates , *MARINE pollution - Abstract
Fucus spiralis, Porphyra sp. and Osmundea pinnatifida are macroalgae consumed as food in some of the Azorean Islands, but little information is available on their nutritional value. This paper presents information on the nutritional aspects in terms of proteins (9.71-24.82%), lipids (5.23-8.88%), soluble carbohydrates (17.59-25.37%), ash (22.31-38.55%), minerals (0.96-1.82 for Na/K ratios) and fat soluble vitamins A (1.20-1.41%) and E (4.86-51.14%) contents on dry weight basis. Fatty acid (SFA, MUFA, PUFA and n6/n3 and h/H ratios) and amino acid profiles, and antioxidant properties were also reported. All the three species contained measurable quantities of 9 of 10 essential amino acids (41.62-63.50% of the total amino acids). The regular consumption of these algae allied with the low level of seawater pollution around Azores Islands will improve human health conditions and will have a protective effect on the most common degenerative diseases. [ABSTRACT FROM AUTHOR] more...
- Published
- 2014
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29. Fatty acid composition of Sargassum (Fucales, Phaeophyta) species harvested from littoral zone of S. Miguel (Azores).
- Author
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Paiva, Lisete, Lima, Elisabete, Baptista, José, Patarra, Rita Ferreira, and Neto, Ana Isabel
- Subjects
MARINE algae ,SARGASSUM ,FATTY acids - Abstract
Copyright of Silva Lusitana is the property of Unidade de Investigacao de Silvicultura e Productos Florestais and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.) more...
- Published
- 2014
30. Bovine Milk Formula Based on Partial Hydrolysis of Caseins by Bromelain Enzyme: Better Digestibility and Angiotensin-Converting Enzyme-Inhibitory Properties.
- Author
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Medeiros, Vera, Rainha, Nuno, Paiva, Lisete, Lima, Elisabete, and Baptista, José
- Subjects
MILK analysis ,HYDROLYSIS ,CASEINS ,BROMELIN ,ACE inhibitors ,MILK enzymes - Abstract
A new methodology was developed using bromelain as a proteolytic enzyme for the production of a partially hydrolyzed bovine milk formula, without changing the milk's organoleptic and nutritional properties. This study also revealed that thein vitroangiotensin-converting enzyme inhibition increased in the modified milk as compared with the control sample, showing the highest angiotensin-converting enzyme-inhibitory activity for fractions with molecular weights between 3 and 10 kg mol−1. The Lineweaver-Burk plot revealed that the produced milk formula acted as a non-competitive inhibitor, as determined by high performance liquid chromatography. [ABSTRACT FROM PUBLISHER] more...
- Published
- 2014
- Full Text
- View/download PDF
31. Content of hypericins from plants and in vitro shoots of Hypericum undulatum Schousb. ex Willd.
- Author
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Rainha, Nuno, Lima, Elisabete, Baptista, José, and Fernandes-Ferreira, Manuel
- Abstract
This study reports the first quantification study of pseudohypericin (PsHyp) and hypericin (Hyp) inHypericum undulatumSchousb. ex Willdin vitrocultures developed by a Portuguese company. Both compounds were quantified by high-performance liquid chromatography and their levels were compared with those in commercial samples ofHypericum perforatum. PsHyp was found to be the major naphthodianthrone ofH. undulatum,with an average ratio of 3.73:1 compared to Hyp. Significant statistical differences were found between the content of Hyp and PsHyp inH. undulatumregenerated shoots compared toin vivosamples. The mean concentration of total Hyps varied from 178.41 to 358.93 µg g−1dry extract inH. undulatumregenerated shoots, which is on average two to three times less than naphthodianthrone levels found inH. undulatum in vivoandH. perforatumcommercial samples. However, none of the analysed samples presented the levels of Hyps required by the European and United States Pharmacopoeias. [ABSTRACT FROM PUBLISHER] more...
- Published
- 2013
- Full Text
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32. Comparison of Azorean tea theanine to teas from other origins by HPLC/DAD/FD. Effect of fermentation, drying temperature, drying time and shoot maturity
- Author
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Baptista, José, Lima, Elisabete, Paiva, Lisete, Andrade, Ana L., and Alves, Maria G.
- Subjects
- *
THEANINE , *TEA , *FERMENTATION , *HIGH performance liquid chromatography , *TEMPERATURE effect , *COMPARATIVE studies , *DRYING - Abstract
Abstract: The objectives of the present study were the determination of theanine (a specific amino acid of tea leaves with repercussion in human neuronal activity) by HPLC with o-phthaldialdehyde derivatisation prior analysis and comparison of its level in samples from different origins or from the same origin (Azores Islands) but with different processing conditions (fermentation, drying temperature and drying time) and shoot maturity. The results revealed a higher level of theanine in the Azorean green tea (3.10%), the only one produced in Europe, as compared with the Chinese, Japanese, Korean and Taiwan green teas that have an average theanine content of 1.52%, 1.34%, 0.89% and 2.76% of the dry weight (dw) of tea leaves, respectively. The fermentation for a longer period of time results in less theanine remaining (2.28% and 3.10% of dw for fermented and non-fermented tea, respectively). The drying temperature and time of the drying process have an inversely strong effect (4.45% and 5.65% of dw for dried at 55°C during 8.50h and at 40°C during 7.10h, respectively). The younger tea shoots have a higher theanine content than mature leaves (7.02% and 6.10% of dw, respectively). Our data suggested that a new type of Azorean theanine-rich tea may be produced by modifying the manufacturing processes of the younger tea shoots. [Copyright &y& Elsevier] more...
- Published
- 2012
- Full Text
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33. Molluscicidal activity of crude water and hexane extracts of Hypericum species to snails ( Radix peregra).
- Author
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Teixeira, Tânia, Rainha, Nuno, Rosa, José Silvino, Lima, Elisabete, and Baptista, José
- Subjects
HYPERICUM ,MOLLUSCICIDES ,FASCIOLIASIS ,PHYTOCHEMICALS ,HEXANE - Abstract
In spite of intense research on both chemical constituency and biological activity of Hypericum species, potential applications of their active components for pest control have been less well investigated. In the present study, Hypericum androsaemum (tutsan), Hypericum foliosum (malfurada), and Hypericum undulatum (wavy St. John's wort) aqueous and hexane extracts were studied for their molluscicidal and ovicidal activities against Radix peregra. The molluscicidal activity of the aqueous extracts was low, except for H. androsaemum infusion (median lethal concentration [LC50]
adults = 317.1 ppm; LC50juveniles = 415 ppm), and less important compared with the toxicity of all three hexane extracts tested: H. androsaemum (LC50adults = 30.47 ppm; LC50juveniles = 73.25 ppm), H. undulatum (LC50adults = 30.55 ppm; LC50juveniles = 60.54 ppm), and H. foliosum (LC50adults = 48.61 ppm; LC50juveniles = 38.81 ppm). An ovicidal effect was observed only with H. androsaemum infusion (1.85% of hatching at 500 ppm) and H. foliosum hexane extract (0.0% of hatching at 100 ppm). A preliminary phytochemical investigation of the lipophylic extracts from these Hypericum sp. revealed a different chemical profile and confirmed the presence of ursolic acid only in H. undulatum as the main compound. The present study indicates that products from hexane extracts of the Hypericum sp. analyzed may be used as potential molluscicides to control snails responsible for transmitting fasciolosis. Environ. Toxicol. Chem. 2012;31:748-753. © 2011 SETAC [ABSTRACT FROM AUTHOR] more...- Published
- 2012
- Full Text
- View/download PDF
34. Comparison of the endemic Azorean Hypericum foliosum with other Hypericum species: antioxidant activity and phenolic profile.
- Author
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Rainha, Nuno, Lima, Elisabete, and Baptista, José
- Abstract
Water extracts of Hypericum foliosum (HF) from five Azorean Islands were analysed for their antioxidant activity and total phenolic contents. The results were compared with those from medicinal Hypericum species (H. perforatum, H. androsaemum and H. undulatum) and also with Azorean green tea. HF exhibited strong scavenging activity (87-91%) and moderate inhibition of linoleic acid oxidation (56-72%), and presented no significant difference to the other studied plants; in contrast, the synthetic antioxidant butylated hydroxyltoluene showed antioxidant activity values of 22% and 88%, respectively. The average value of phenolics in HF was higher than that in the other Hypericum species and lower than that in tea. Additionally, the phenolic profiles of the Hypericum species were compared by reverse phase-high performance liquid chromatography/ultraviolet (RP-HPLC/UV). The method presented permits the simultaneous determination of phenolic acids, flavonoids, hypericin and hyperforin within 55 min. The most similar profile was observed between HF and H. androsaemum. This study indicates that HF is a source of bioactive compounds with potential health benefits. [ABSTRACT FROM AUTHOR] more...
- Published
- 2011
- Full Text
- View/download PDF
35. Marine Organisms as Alkaloid Biosynthesizers of Potential Anti-Alzheimer Agents.
- Author
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Lima, Elisabete and Medeiros, Jorge
- Abstract
The incidence of neurodegenerative diseases, such as Alzheimer's disease (AD), increases continuously demanding the urgent development of anti-Alzheimer's agents. Marine organisms (MO) have to create their own defenses due to the adverse environment where they live and so synthesize several classes of compounds, such as akaloids, to defend themselves. Therefore, the identification of marine natural products with neuroprotective effects is a necessity. Being that AD is not only a genetic but also an environmental complex disease, a treatment for AD remains to discover. As the major clinical indications (CI) of AD are extracellular plaques formed by β-amyloid (Aβ) protein, intracellular neurofibrillary tangles (NFTs) formed by hyper phosphorylated τ-protein, uncommon inflammatory response and neuron apoptosis and death caused by oxidative stress, alkaloids that may decrease CI, might be used against AD. Most of the alkalolids with those properties are derivatives of the amino acid tryptophan mainly with a planar indole scaffold. Certainly, alkaloids targeting more than one CI, multitarget-directed ligands (MTDL), have the potential to become a lead in AD treatment. Alkaloids to have a maximum of activity against CI, should be planar and contain halogens and amine quaternization. [ABSTRACT FROM AUTHOR] more...
- Published
- 2022
- Full Text
- View/download PDF
36. Comparative Analysis of the Polyphenols, Caffeine, and Antioxidant Activities of Green Tea, White Tea, and Flowers from Azorean Camellia sinensis Varieties Affected by Different Harvested and Processing Conditions.
- Author
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Paiva, Lisete, Rego, Clara, Lima, Elisabete, Marcone, Massimo, Baptista, José, and D'Angelo, Stefania
- Subjects
TEA ,GREEN tea ,PLANT polyphenols ,EPIGALLOCATECHIN gallate ,POLYPHENOLS ,GALLIC acid ,BUTYLATED hydroxytoluene - Abstract
This study evaluates the polyphenol profiles as well as caffeine (dry weight basis), and antioxidant activities of green tea (GTs), white tea (WTs), and flowers (Fl) samples from Azorean Camellia sinensis varieties affected by different harvested and processing conditions. Epicatechins derivatives, determined by RP-HPLC/PDAD, presented higher values in GTs with respect to WTs, decreasing as follows: epigallocatechin-3-gallate > epicatechin-3-gallate ≫ epicatechin ≫ epigallocatechin, and higher values in summer and early autumn than in spring. This was also accompanied by an in consistent withering time pattern. Esterified catechins were higher in all samples (100.8–312.3 mg/g) with respect to non-esterified catechins (15.1–37.7 mg/g). Caffeine (6.2–27.7 mg/g) decreased as follows: WTs > GTs ≫ Fl, and inconsistent seasonal and withering patterns were observed among the WTs. Total phenolics (125.9–295.4 mg gallic acid equivalents/g dried extract) and total flavonoids (35.2–69.7 mg rutin equivalents/g dried extract), determined by Folin–Ciocalteu and colorimetric methodologies, were higher in GTs than in WTs and Fl. Concerning the antioxidant patterns, the free radical scavenging activity (FRSA) and ferric reducing antioxidant power (FRAP) presented EC
50 values ranges from 3.6 to 17.3 µg/mL and 4.8 to 16.5 µg/mL, respectively, and ferrous ion-chelating (FIC) activity ranged from 47.1 to 82.8%, highlighting that FRSA was better than butylated hydroxytoluene (BHT). Tea leaves exhibited, in general, higher activities with respect to tea Fl, and the WT sample plucked in summer and withered for 23 h showed the highest FRAP and FIC activity. In conclusion, this study shows the characteristic variation of GTs, WTs, and Fl of two tea varieties and may support crop quality improvement and promote the valorization of tea Fl. [ABSTRACT FROM AUTHOR] more...- Published
- 2021
- Full Text
- View/download PDF
37. Seasonal Variability of the Biochemical Composition and Antioxidant Properties of Fucus spiralis at Two Azorean Islands.
- Author
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Paiva, Lisete, Lima, Elisabete, Baptista, José, and Neto, Ana Isabel
- Abstract
This study evaluates, for the first time, the seasonal (winter and summer) and geographical (São Miguel–SMG and Santa Maria–SMA Islands) variability of
Fucus spiralis (Fs) biochemical composition (dry weight basis) and antioxidant properties. Protein and carbohydrates presented higher values in Fs-SMGwinter , lipids, total dietary fiber, and energy value in Fs-SMAsummer , and ash and soluble dietary fiber/insoluble dietary fiber ratio in Fs-SMAwinter . The fatty acid (FA) profiles showed a lower SFA in Fs-SMGsummer , whereas MUFA and PUFA presented higher values in Fs-SMGsummer and Fs-SMGwinter , respectively. Excellent dietary ratios ofn 6/n 3 PUFA and hypocholesterolemic/hypercholesterolemic FA were found, with lower values in Fs-SMAwinter and higher in Fs-SMGsummer , respectively. The highest total phenolics was found in Fs-SMAsummer acetone:water extract and total flavonoids showed the higher value in Fs-SMGwinter methanol extract. The best free radical-scavenging activity was observed in the Fs-SMAwinter methanol (EC50 = 0.045 mg/mL) and acetone:water (EC50 = 0.059 mg/mL) extracts. The ferric-reducing antioxidant power showed the best results in Fs-SMAwinter methanol extract (EC50 = 0.016 mg/mL) and Fs-SMAsummer acetone:water extract (EC50 = 0.017 mg/mL). The best ferrous ion-chelating activity was found in Fs-SMGwinter acetone:water extract. Overall, results revealed thatF. spiralis nutritional and functional bioactivity values have geographical and seasonal variations and that its regular consumption may add benefits to human health. [ABSTRACT FROM AUTHOR] more...- Published
- 2018
- Full Text
- View/download PDF
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